---++ <b><font color="blue" size="+3">Lesson Diary of the Previous Years</font></b> ---+++ <font color="red" size="+1">Lesson Diary A.y. 2023-2024</font> ---+++ *Introduction* *The Routing Problem i.e. the Least Cost Path Problem (1)* * The routing Problem * The shortest path Problem * shortest paths: BFS * The least cost path Problem (1) * the negative cycle issue * least cost paths: introduction * Bellman-Ford algorithm * Dijkstra algorithm (part) %GREEN% *Thursday, September 28, 2023 (Lessons 4-5):* %ENDCOLOR% *The Routing Problem i.e. the Least Cost Path Problem (2)* * The least cost path Problem (2) * Dijkstra algorithm (part) * Floyd-Warshall algorithm * The Routing Problem on Interconnection Topologies * the packet-switching model * the Butterfly network * routing on the Butterfly network: the greedy algorithm * The concept of blocking network, non-blocking network, and rearrangeable network %GREEN% *Monday, October 2, 2023 (Lessons 6-7-8):* %ENDCOLOR% *The Routing Problem i.e. the Least Cost Path Problem (3)* * The Routing Problem on Interconnection Topologies * The Benes network * routing on the Benes network: the looping algorithm *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (1)* * The Thompson model * The orthogonal grid drawing of graphs * Layout of the complete binary tree (H-tree) * Collinear Layout of the Complete network * Layout of the Complete network * Relation between bisection width and layout area * Layout of the Butterfly network * The Wise layout %GREEN% *Thursday, October 5, 2023 (Lessons 9-10):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (2)* * Layout of the Butterfly network * The Even & Even layout * comparison between the two methods * Optimal area layout %GREEN% *Monday, October 9, 2023 (Lessons 11-12-13):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (3)* * Layout of the Hypercube network * Collinear layout * general layout * The 3D layout problem *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (1)* * The problem * worms * damages caused by worms * Model of the problem on graphs: minimum vertex cover * Definition * ILP model * a 2-approximation algorithm * independent set and maximum matching in relation to vertex cover * another approximation algorithm %GREEN% *Thursday October 12, 2023 (Lessons 14-15):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (2)* * Model of the problem on graphs: minimum vertex cover * Konig-Egevary theorem (without proof) * A related problem: eternal vertex problem *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems %GREEN% *Monday October 16, 2023 (Lessons 16-17-18):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2)* * Direct and hidden collisions, interference graph * Introduction to the frequency assignment problems * Direct and hidden collisions, interference graph * L(h,k)-labeling and minimum span (1) * The special case h=k in relation to the square of a graph * Properties of the L(h,k)-labeling and their proofs * Proof of NP-completeness for diameter 2 graphs * Lower bound of Delta+1 on lambda * Example: a graph requiring lambda=Delta squared - Delta * Upper bound of Delta squared + 2 Delta * Griggs and Yeh's conjecture * Exact results: cliques * Exact results: stars * Exact results: trees * Exact results: paths * Exact results: cycles * Exact results: grids * Approximate results: outerplanar graphs %GREEN% *Thursday, October 19, 2023 (Lessons 22-23):* %ENDCOLOR% *Special guest:* Jan Arne Telle - University of Bergen - https://www.uib.no/en/persons/Jan.Arne.Telle *Seminar entitled:* Recognition of Linear and Star Variants of Leaf Powers is in P %GREEN% *Monday, October 23, 2023 (Lessons 24-25-26):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (3)* * Variations of the problem * oriented L(2,1)-labeling * L(h1, ..., hk)-labeling * backbone coloring * multiple L(h,k)-labeling * a parenthesis on the 4-color theorem *The minimum energy broadcast i.e. the minimum spanning tree (1)* * The Min Broadcast problem * NP-completeness and inapproximability results (reduction from Min Set Cover) * Relation between Min Broadcast and Min Spanning Tree (MST) %GREEN% *Thursday, October 26, 2023 (Lessons 27-28):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (2)* * The MST problem * Kruskal algorithm * Prim algorithm * Boruvka algorithm * The Min Broadcast problem * MST heuristics * SPT heuristics * BAIP heuristics * approximation ratio for MST %RED% *Mid-term exam: first part* %ENDCOLOR% %GREEN% *Monday, October 30, 2023 (Lessons 29-30-31):* %ENDCOLOR% *The data mule problem i.e. the TSP* * (Fixed) sensor networks * The Data Mule problem * The TSP * NP-completeness * inapproximability * special cases: metric TSP and Euclidean TSP * generalizations *The Data Collection in ad-hoc networks i.e. the connected Dominating Set Problem* * the connected dominating set problem * the dominating set problem * the connected dominating set problems in unit disk graphs %GREEN% *Thursday, November 2, 2023 (Lessons 32-33):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (1)* * (mobile) sensor networks %RED% *Mid-term exam: second part* %ENDCOLOR% %GREEN% *Monday November 6, 2023 (Lessons 34-35-36):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs(2)* * The problem of centralized deployment * The problem on graphs: min weight matching in bipartite graphs * maximum matching in a bipartite graph * P. Hall theorem (with proof) * corollary to the P. Hall theorem * searching for an augmenting path * Berge theorem on the augmenting paths * algorithm based on Berge theorem * Hopcroft & Karp algorithm * augmenting paths * an algorithm based on searching augmenting paths * ILP formulation %GREEN% *Thursday, November 9, 2023 (Lessons 37-38):* %ENDCOLOR% %RED% *Mid-term exam: third part* %ENDCOLOR% %GREEN% *Monday November 13, 2023 (Lessons 39-40-41):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (3)* * Maximum matching in general graphs * blossoms * lemma on the cycle contraction * Edmonds algorithm (idea) * Another application *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (1)* * The problem * A Possible Approach: Virtual Forces * A Protocol Based on Voronoi Diagrams * Voronoi Diagrams * hypothesis of general position * properties * complexity * the dual problem: Delaunay triangulation * half-plane intersection (divide et impera) %GREEN% *Thursday November 16, 2023 (Lessons 42-43):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (2)* * Algorithms to compute the Voronoi diagram * Fortune algorithm %RED%students'opinions questionnaire - OPIS code: 73X3JB6A (1st year students) and SIJ1BMJY (2nd year students) %ENDCOLOR% [[%ATTACHURL%/guided_path_to_access_student_s_opinions_questionnaire_2022_2023.pdf][HERE]]: instructions for student's opinions questionnaire 2022/2023 %GREEN% *Monday, November 20, 2023 (Lessons 44-45-46):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (3)* * Heterogeneous sensors * A new notion of distance: Laguerre distance * Voronoi-Laguerre diagrams * A protocol based on Voronoi-Laguerre distance *Monitoring by UAVs i.e. what? (+some open problems)* %RED% *Thursday, November 23, 2023* %ENDCOLOR% *Canceled* %GREEN% *Monday, November 27, 2023 (Lessons 47-48-49):* %ENDCOLOR% *Other kinds of networks: the phylogeny and medicine cases (+some open problems)* %RED% *Thursday, November 30, 2023* %ENDCOLOR% *Canceled* %GREEN% *Monday, December 4, 2023 (Lessons 50-51-52):* %ENDCOLOR% *Student lessons*: Cukaj, Factor, Fiusco, Korpal, Pinna, Pro %GREEN% *Thursday, December 7, 2023 (Lessons 53-54):* %ENDCOLOR% *Student lessons*: Lundholm, Moldovan, Zhou %GREEN% *Monday, December 11, 2023 (Lessons 55-56-57):* %ENDCOLOR% *Student lessons*: Bertagnoli, D'Ambrosio, Finelli, Florescu, Gaetani, Guarini, Loffredi %RED% *Thursday, December 14, 2023* %ENDCOLOR% *Canceled* %GREEN% *Monday, December 18, 2023 (Lessons 58-59-60):* %ENDCOLOR% %RED% *Mid-term exam* %ENDCOLOR% ---+++ <font color="red" size="+1">Lesson Diary A.y. 2022-2023</font> ---+++ %GREEN% *Tuesday September 27, 2022 (Lessons 1-2-3):* %ENDCOLOR% *Introduction* *The Routing Problem i.e. the Least Cost Path Problem (1)* * The routing Problem * The shortest path Problem * shortest paths: BFS * The least cost path Problem (1) * the negative cycle issue * least cost paths: introduction * Bellman-Ford algorithm * Dijkstra algorithm %GREEN% *Friday September 30, 2022 (Lessons 4-5):* %ENDCOLOR% *The Routing Problem i.e. the Least Cost Path Problem (2)* * The least cost path Problem (2) * Floyd-Warshall algorithm * The Routing Problem on Interconnection Topologies * the packet switching model * the Butterfly network * routing on the Butterfly network: the greedy algorithm * the concept of blocking network, non-blocking network and rearrangeable network * the Benes network * routing on the Benes network: the looping algorithm %GREEN% *Tuesday October 4, 2022 (Lessons 6-7-8):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (1)* * The Thompson model * The orthogonal grid drawing of graphs * Layout of the complete binary tree (H-tree) * Collinear Layout of the Complete network * Layout of the Complete network * Relation between bisection width and layout area * Layout of the Butterfly network * the Wise layout * the Even & Even layout * comparison between the two methods %GREEN% *Friday October 7, 2022 (Lessons 9-10):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (3)* * Layout of the Butterfly network * Optimal area layout * Layout of the Hypercube network * Collinear layout * general layout * The 3D layout problem %GREEN% *Tuesday October 11, 2022 (Lessons 11-12-13):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (1)* * The problem * worms * damages caused by worms * Model of the problem on graphs: minimum vertex cover * definition * ILP model * a 2-approximation algorithm * independent set and maximum matching in relation with vertex cover * another approximation algorithm * Konig-Egevary theorem (without proof) * A related problem: eternal vertex problem %GREEN% *Friday October 14, 2022 (Lessons 14-15):* %ENDCOLOR% *The Problem of Minimizing Boolean Circuits i.e. the Minimum Set Covering Problem* * The problem of minimizing boolean functions * Model of the problem on graphs: the Minimum Set Cover Problem * definition * ILP formulation * relation with the Minimum Vertex Covering Problem * an O(log n)-approximation algorithm * another approximation algorithm * some related problems: * Hitting set problem * Edge Cover problem * Set Packing problem * Exact Cover problem *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems %GREEN% *Tuesday October 18, 2022 (Lessons 16-17-18):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2)* * Direct and hidden collisions, interference graph * Introduction to the frequency assignment problems * Direct and hidden collisions, interference graph * L(h,k)-labeling and minimum span (1) * The special case h=k in relation to the suqre of a graph * Properties of the L(h,k)-labeling and their proofs * Proof of NP-completeness for diameter 2 graphs %GREEN% *Friday October 21, 2022 (Lessons 19-20):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2)* * L(h,k)-labeling and minimum span (2) * Lower bound of Delta+1 on lambda * Example: a graph requiring lambda=Delta squared - Delta * Upper bound of Delta squared + 2 Delta * Griggs and Yeh's conjecture * Exact results: cliques * Exact results: stars * Exact results: trees * Exact results: paths * Exact results: cycles * Exact results: grids * Approximate results: outerplanar graphs %GREEN% *Tuesday October 25, 2022 (Lessons 21-22-23):* %ENDCOLOR% %BLUE% students' lesson 1: The Routing problem i.e. the minimum cost shortest path %ENDCOLOR% %BLUE% students' lesson 2: The layout of interconnection networks i.e. the orthogonal grid graph drawing %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (3)* * Variations of the problem * oriented L(2,1)-labeling * L(h1, ..., hk)-labeling * backbone coloring * multiple L(h,k)-labeling * frequency assignment in GSM networks * a parenthesis on the 4 color theorem %GREEN% *Friday October 28, 2022 (Lessons 24-25):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (1)* * the Min Broadcast problem * NP-completeness and inapproximability results (reduction from Min Set Cover) * Relation between Min Broadcast and Min Spanning Tree (MST) * The MST problem * Kruskal algorithm * Prim algorithm * Boruvka algorithm %RED% *Tuesday November 1, 2022: HOLIDAY* %ENDCOLOR% %GREEN% *Friday November 4, 2022 (Lessons 26-27):* %ENDCOLOR% %BLUE% students' lesson 3: The problem of infecting a network with a worm i.e. the minimum vertex cover problem %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (2)* * the Min Broadcast problem * MST heuristics * SPT heuristics * BAIP heuristics * approximation ratio for MST *The data mule problem i.e. the TSP (1)* * (Fixed) sensor networks * The Data Mule problem %GREEN% *Tuesday November 8, 2022 (Lessons 28-29-30):* %ENDCOLOR% %BLUE% students' lesson 4: The problem of minimizing a boolean circuit i.e. the minimum set covering problem %ENDCOLOR% *The data mule problem i.e. the TSP (2)* * The TSP * NP-completeness * inapproximability * special cases: metric TSP and Euclidean TSP * generalizations *the Data Collection in ad-hoc networks i.e. the connected Dominating Set Problem (1)* * the data collection problem %RED% *Friday November 11, 2022 (Lessons 31-32-33): FIRS MID-TERM EXAM* %ENDCOLOR% %GREEN% *Tuesday November 15, 2022 (Lessons 34-35-36):* %ENDCOLOR% %BLUE% students' lesson 5: The frequency assignment problem i.e. a graph coloring problem %ENDCOLOR% %BLUE% students' lesson 6: The minimum energy broadcast problem i.e. the minimum spanning tree problem %ENDCOLOR% *the Data Collection in ad-hoc networks i.e. the connected Dominating Set Problem (2)* * the connected dominating set problem * the dominating set problem * the connected dominating set problems in unit disk graphs *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (1)* * (mobile) sensor networks %GREEN% *Friday November 18, 2022 (Lessons 37-38):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (2)* * the problem of centralized deployment * the problem on graphs: min weight matching in a bipartite graphs * maximum matching in a bipartite graph * P. Hall theorem (with proof) * corollary to the P. Hall theorem * searching an augmenting path * Berge theorem on the augmenting paths * algorithm based on Berge theorem * Hopcroft & Karp algorithm %GREEN% *Tuesday November 22, 2022 (Lessons 39-40-41):* %ENDCOLOR% %BLUE% students' lesson 7: The data mule scheduling problem i.e. the travelling salesman problem %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (3)* * Minimum weight perfect matching in bipartite graphs (cntd) * augmenting paths * an algorithm based on searching augmenting paths * ILP formulation * Maximum matching in general graphs * blossoms * lemma on the cycle contraction * Edmonds algorithm (idea) * Another application %GREEN% *Friday November 25, 2022 (Lessons 42-43):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (1)* * The problem * A Possible Approach: Virtual Forces * A Protocol Based on Voronoi Diagrams * Voronoi Diagrams * hypthesis of general position * properties * complexity * the dual problem: Delaunay triangulation %GREEN% *Tuesday November 29, 2022 (Lessons 44-45-46):* %ENDCOLOR% %BLUE% students' lesson 8: The centralized deployment of a mobile sensor network i.e. the minimum cost perfect matching in bipartite graphs %ENDCOLOR% %RED%students'opinions questionnaire - OPIS code: R053WYBC %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (2)* * Algorithms to compute the Voronoi diagram * half-plane intersection (divide et impera) * Fortune algorithm %GREEN% *Friday December 2, 2022 (Lessons 47-48):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (3)* * Heterogeneous sensors * A new notion of distance: Laguerre distance * Voronoi-Laguerre diagrams * A protocol based on Voronoi-Laguerre distance %GREEN% *Tuesday December 6, 2022 (Lessons 49-50-51):* %ENDCOLOR% %BLUE% students' lesson 9: Self-deployment of a mobile sensor network i.e. the Voronoi Diagram %ENDCOLOR% *Monitoring by UAVs i.e. the multiple TSP with constraints* %RED% *Friday December 9, 2022: LONG WEEKEND: the University is closed* %ENDCOLOR% %GREEN% *Tuesday December 13, 2022 (Lessons 52-53-54)* %ENDCOLOR% %BLUE% students' lesson 10: Monitoring by UAVs i.e. the multiple TSP with constraints %ENDCOLOR% *Other kinds of networks: the phylogeny and medicine cases (+some open problems)* %RED% *Friday December 16, 2022 (Lessons 55-56): no lesson* %ENDCOLOR% %RED% *Tuesday December 20, 2022 (Lessons 57-58-59): SECOND MID-TERM EXAM* %ENDCOLOR% ---++ <font color="red" size="+3">Lesson Diary A.y. 2021-2022</font> %GREEN% *Wednesday September 22, 2021 (Lessons 1-2-3):* %ENDCOLOR% *Introduction* *The Routing Problem i.e. the Least Cost Path Problem (1)* * The routing Problem * The shortest path Problem * shortest paths: BFS * The least cost path Problem * the negative cycle issue * least cost paths: introduction %GREEN% *Friday September 24, 2021:* %ENDCOLOR% *No lesson* %GREEN% *Wednesday September 29, 2021 (Lessons 4-5-6):* %ENDCOLOR% *The Routing Problem i.e. the Least Cost Path Problem (2)* * The least cost path Problem * Bellman-Ford algorithm * Dijkstra algorithm * Floyd-Warshall algorithm * The Routing Problem on Interconnection Topologies * the packet switching model * the Butterfly network * routing on the Butterfly network: the greedy algorithm %GREEN% *Friday October 1, 2021 (Lessons 7-8):* %ENDCOLOR% *The Routing Problem i.e. the Least Cost Path Problem (3)* * The Routing Problem on Interconnection Topologies * the concept of blocking network, non-blocking network and rearrangeable network * the Benes network * routing on the Benes network: the looping algorithm *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (1)* * The Thompson model * The orthogonal grid drawing of graphs %GREEN% *Wednesday October 6, 2021 (Lessons 9-10-11):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (2)* * Collinear Layout of the Complete network * Layout of the Complete network * Relation between bisection width and layout area * Layout of the Butterfly network * the Wise layout * the Even & Even layout %GREEN% *Friday October 8, 2021 (Lessons 12-13):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (3)* * Layout of the Butterfly network * summary of the last lesson hour (the video went lost) * comparison between the two methods * Layout of the Hypercube network * Collinear layout * general layout * The 3D layout problem %GREEN% *Wednesday October 13, 2021 (Lessons 14-15-16):* %ENDCOLOR% *A parenthesis: Some problems in (co-)phylogeny (some theses' proposals)* *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (2)* * The problem * worms * damages caused by worms %GREEN% *Friday October 15, 2021 (Lessons 17-18):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (2)* * Model of the problem on graphs: minimum vertex cover * definition * ILP model * a 2-approximation algorithm * independent set and maximum matching in relation with vertex cover * another approximation algorithm * Konig-Egevary theorem (without proof) * A related problem: eternal vertex problem %GREEN% *Wednesday October 20, 2021 (Lessons 19-20-21):* %ENDCOLOR% *The Problem of Minimizing Boolean Circuits i.e. the Minimum Set Covering Problem* * The problem of minimizing boolean functions * Model of the problem on graphs: the Minimum Set Cover Problem * definition * ILP formulation * relation with the Minimum Vertex Covering Problem * an O(log n)-approximation algorithm * another approximation algorithm * some related problems: * Hitting set problem * Edge Cover problem * Set Packing problem * Exact Cover problem *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems * Direct and hidden collisions, interference graph %GREEN% *Friday October 22, 2021 (Lessons 22-23):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems * Direct and hidden collisions, interference graph * L(h,k)-labeling and minimum span (1) * The special case h=k in relation to the suqre of a graph * Properties of the L(h,k)-labeling and their proofs * Proof of NP-completeness for diameter 2 graphs (first part) %GREEN% *Wednesday October 27, 2021 (Lessons 24-25-26):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2)* * L(h,k)-labeling and minimum span (2) * Proof of NP-completeness for diameter 2 graphs * Lower bound of Delta+1 on lambbda * Example: a graph requiring lambda=Delta squared - Delta * Upper bound of Delta squared + 2 Delta * Griggs and Yeh's conjecture * Exact results: cliques * Exact results: stars * Exact results: trees * Exact results: paths * Exact results: cycles * Exact results: grids %GREEN% *Friday October 29, 2021 (Lessons 27-28-29):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (3)* * L(h,k)-labeling and minimum span (3) * Approximate results: outerplanar graphs * Variations of the problem (1) * oriented L(2,1)-labeling * L(h1, ..., hk)-labeling * backbone coloring * multiple L(h,k)-labeling * frequency assignment in GSM networks %GREEN% *Week November 2-5, 2021: Mid-term exams* %ENDCOLOR% %GREEN% *Wednesday November 10, 2021 (Lessons 30-31-32):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (4)* * L(h,k)-labeling and minimum span (4) * Variations of the problem (2) * a parenthesis on the 4 color theorem *The minimum energy broadcast i.e. the minimum spanning tree (1)* * the Min Broadcast problem * NP-completeness and inapproximability results (reduction from Min Set Cover) * Relation between Min Broadcast and Min Spanning Tree (MST) %GREEN% *Friday November 12, 2021 (Lessons 33-34):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (2)* * The MST problem * Kruskal algorithm * Prim algorithm * Boruvka algorithm %GREEN% *Wednesday November 17, 2021 (Lessons 35-36-37):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (3)* * the Min Broadcast problem * MST heuristics * SPT heuristics * BAIP heuristics * approximation ratio for MST *The data mule problem i.e. the TSP (1)* * (Fixed) sensor networks * The Data Mule problem * The TSP * NP-completeness * inapproximability %GREEN% *Friday November 19, 2021 (Lessons 38-39):* %ENDCOLOR% *The data mule problem i.e. the TSP (2)* * * special cases: metric TSP and Euclidean TSP * generalizations *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (1)* * (mobile) sensor networks %GREEN% *Wednesday November 24, 2021 (Lessons 40-41-42):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (2)* * the problem of centralized deployment * the problem on graphs: min weight matching in a bipartite graphs * maximum matching in a bipartite graph * P. Hall theorem (with proof) * corollary to the P. Hall theorem * searching an augmenting path * Berge theorem on the augmenting paths * algorithm based on Berge theorem * Hopcroft & Karp algorithm %GREEN% *Friday November 26, 2021 (Lessons 43-44):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (3)* * Minimum weight perfect matching in bipartite graphs (cntd) * augmenting paths * an algorithm based on searching augmenting paths * ILP formulation * Maximum matching in general graphs * blossoms * lemma on the cycle contraction * Edmonds algorithm (idea) * Another application %GREEN% *Wednesday December 1, 2021 (Lessons 45-46-47):* %ENDCOLOR% %RED% *Students' lessons* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (1)* * The problem * A Possible Approach: Virtual Forces * A Protocol Based on Voronoi Diagrams * Voronoi Diagrams * hypthesis of general position * properties * complexity * the dual problem: Delaunay triangulation %GREEN% *Friday December 3, 2021 (Lessons 48-49):* %ENDCOLOR% %RED% *Students' lessons* [BKTL04], [BPT00], [Bal07], [AGK08], [Xal14] %ENDCOLOR% %RED% *Wednesday December 8, 2021: HOLIDAY* %ENDCOLOR% %GREEN% *Friday December 10, 2021 (Lessons 50-51):* %ENDCOLOR% %RED% *Students' lessons* [M95], [Cal15] %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (2)* * Algorithms to compute the Voronoi diagram * half-plane intersection (divide et impera) * Fortune algorithm %GREEN% *Wednesday December 15, 2021 (Lessons 52-53-54):* %ENDCOLOR% %RED% *Students' lessons* [HZ14], [YWD06], [NSM16], [ML18] %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (3)* * Heterogeneous sensors * A new notion of distance: Laguerre distance * Voronoi-Laguerre diagrams * A protocol based on Voronoi-Laguerre distance *Monitoring by UAVs i.e. what? (some theses' proposals)* %GREEN% *Friday December 17, 2021 (Lessons 55-56): mid-term exam* %ENDCOLOR% %GREEN% *Wednesday December 22, 2021: no lesson* %ENDCOLOR% -- ---+ %RED%Lesson Diary A.y. 2020-2021%ENDCOLOR% %GREEN% *Wednesday October 7, 2020 (Lessons 1-2-3):* %ENDCOLOR% *Introduction* *The Routing Problem i.e. the Least Cost Path Problem (1)* * The routing Problem * The shortest path Problem * shortest paths: BFS * The least cost path Problem * the negative cycle issue * least cost paths: introduction %GREEN% *Friday October 9, 2020 (Lessons 4-5):* %ENDCOLOR% *The Routing Problem i.e. the Least Cost Path Problem (2)* * The least cost path Problem * Bellman-Ford algorithm * Dijkstra algorithm * Floyd-Warshall algorithm * The Routing Problem on Interconnection Topologies * the packet switching model * the Butterfly network * routing on the Butterfly network: the greedy algorithm %GREEN% *Wednesday October 14, 2020 (Lessons 6-7-8):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (3)* * The Routing Problem on Interconnection Topologies (2) * the concept of blocking network, non-blocking network and rearrangeable network * the Benes network * routing on the Benes network: the looping algorithm *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (1)* * The Thompson model * The orthogonal grid drawing of graphs * Collinear Layout of the Complete network * Layout of the Complete network * Relation between bisection width and layout area * Layout of the Butterfly network * the Wise layout %GREEN% *Friday October 16, 2020 (Lessons 9-10):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (2)* * Layout of the Butterfly network * the Even & Even layout * comparison between the two methods * Layout of the Hypercube network * Collinear layout * general layout * The 3D layout problem %GREEN% *Wednesday October 21, 2020 (lessons 11-12-13):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem* * The problem * worms * damages caused by worms * Model of the problem on graphs: minimum vertex cover * definition * ILP model * a 2-approximation algorithm * independent set and maximum matching in relation with vertex cover * another approximation algorithm * Konig-Egevary theorem (without proof) * A related problem: eternal vertex problem %GREEN% *Friday October 23, 2020 (lessons 14-15):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems * Direct and hidden collisions, interference graph * L(h,k)-labeling and minimum span (1) * The special case h=k in relation to the suqre of a graph * Properties of the L(h,k)-labeling and their proofs %GREEN% <b>Wednesday October 28, 2020 (lessons 16-17-18):* </b>%ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2) * L(h,k)-labeling and minimum span (2) * Proof of NP-completeness for diameter 2 graphs * Lower bound of Delta+1 on lambbda * Example: a graph requiring lambda=Delta squared - Delta * Upper bound of Delta squared + 2 Delta * Griggs and Yeh's conjecture * Exact results: cliques * Exact results: stars * Exact results: trees * Exact results: paths * Exact results: cycles * Approximate results: outerplanar graphs * Variations of the problem * oriented L(2,1)-labeling * L(h1, ..., hk)-labeling * backbone coloring * multiple L(h,k)-labeling * frequency assignment in GSM networks * a parenthesis on the 4 color theorem %GREEN% *Friday October 30, 2020 (lessons 19-20):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (1)* * the Min Broadcast problem * NP-completeness and inapproximability results (reduction from Min Set Cover) * Relation between Min Broadcast and Min Spanning Tree (MST) %GREEN% *Wednesday November 4, 2020 (lessons 21-22-23):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (2)* * The MST problem * Kruskal algorithm * Prim algorithm * Boruvka algorithm * the Min Broadcast problem * MST heuristics * SPT heuristics * BAIP heuristics * approximation ratio for SPT %GREEN% *Friday November 6, 2020 (lessons 24-25):* %ENDCOLOR% *The data mule problem i.e. the TSP (1)* * (Fixed) sensor networks * The Data Mule problem * The TSP * NP-completeness * inapproximability %GREEN% *Wednesday November 11, 2020 (lessons 26-27-28):* %ENDCOLOR% *The data mule problem i.e. the TSP (2)* * * special cases: metric TSP and Euclidean TSP * generalizations *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (1)* * (mobile) sensor networks * the problem of centralized deployment * the problem on graphs: min weight matching in a bipartite graphs * maximum matching in a bipartite graph * P. Hall theorem (with proof) * corollary to the P. Hall theorem * searching an augmenting path %GREEN% *Friday November 13, 2020 (lessons 29-30):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (2)* * maximum matching in a bipartite graph (cntd) * Berge theorem on the augmenting paths * algorithm based on Berge theorem * Hopcroft & Karp algorithm * Minimum weight perfect matching in bipartite graphs * augmenting paths * an algorithm based on searching augmenting paths * ILP formulation * Maximum matching in general graphs * blossoms * lemma on the cycle contraction %GREEN% *Wednesday November 18, 2020 (lessons 31-32-33):* %ENDCOLOR% *Students' lessons (1)* *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (3)* * Maximum matching in general graphs (cntd) * blossoms * lemma on the cycle contraction * Edmonds algorithm (idea) *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (1)* * The problem * A Possible Approach: Virtual Forces * A Protocol Based on Voronoi Diagrams * Voronoi Diagrams * hypthesis of general position %GREEN% *Friday November 20, 2020 (lessons 34-35):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (2)* * Voronoi Diagrams (cntd) * properties * complexity * the dual problem: Delaunay triangulation * Algorithms to compute the Voronoi diagram (1) * half-plane intersection (divide et impera) %GREEN% *Wednesday November 25, 2020 (lessons 36-37-38):* %ENDCOLOR% *Students' lessons (2)* *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (3)* * Voronoi Diagrams (cntd) * Fortune algorithm * Heterogeneous sensors * A new notion of distance: Laguerre distance * Voronoi-Laguerre diagrams * A protocol based on Voronoi-Laguerre distance %GREEN% *Friday November 27, 2020 (lessons 39-40):* %ENDCOLOR% *Mid Term Exam 1/2* %GREEN% *Wednesday December 2, 2020 (lessons 41-42-43):* %ENDCOLOR% *Students' lessons (3)* *The Problem of Minimizing Boolean Circuits i.e. the Minimum Set Covering Problem* * The problem of minimizing boolean functions * Model of the problem on graphs: the Minimum Set Cover Problem * definition * ILP formulation * relation with the Minimum Vertex Covering Problem * an O(log n)-approximation algorithm * another approximation algorithm * some related problems: * Hitting set problem * Edge Cover problem * Set Packing problem * Exact Cover problem %GREEN% *Friday December 4, 2020 (lessons 44-45):* %ENDCOLOR% *Monitoring by UAVs i.e. what? (some theses' proposals)* %GREEN% *Wednesday December 9, 2020 (lessons 46-47-48):* %ENDCOLOR% *Students' lessons (4)* * Dr. Federico Corò: "A Realistic Model to Support Rescue Operationsby UAVs after an Earthquake" %GREEN% *Friday December 11, 2020 (lessons 49-50):* %ENDCOLOR% *Some problems in (co-)phylogeny (some further theses' proposals)* %GREEN% *Wednesday December 16, 2020 (lessons 51-52-53):* %ENDCOLOR% *Students' lessons (5)* %GREEN% *Friday December 18, 2020 (lessons 54-55):* %ENDCOLOR% *Mid Term Exam 2/2* ---- ---++ <font color="red" size="+3">Lesson Diary A.y. 2019-2020</font> %GREEN% *Wednesday September 25, 2019 (Lessons 1-2-3):* %ENDCOLOR% *Introduction* *The Routing Problem i.e. the Least Cost Path Problem (1)* * The routing Problem * The shortest path Problem * shortest paths: BFS * The least cost path Problem * the negative cycle issue * least cost paths: introduction * Bellman-Ford algorithm * Dijkstra algorithm * Floyd-Warshall algorithm %GREEN% *Friday September 27, 2019 (Lessons 4-5):* %ENDCOLOR% *The Routing Problem i.e. the Least Cost Path Problem (2)* * The Routing Problem on Interconnection Topologies * the packet switching model * the Butterfly network * routing on the Butterfly network: the greedy algorithm * the concept of blocking network, non-blocking network and rearrangeable network * the Benes network * routing on the Benes network: the looping algorithm %GREEN% *Wednesday October 2, 2019 (Lessons 6-7-8):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (3)* * The Routing Problem on Interconnection Topologies (2) * the Benes network * routing on the Benes network: the looping algorithm *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (1)* * The Thompson model * The orthogonal grid drawing of graphs * Collinear Layout of the Complete network * Layout of the Complete network * Relation between bisection width and layout area %GREEN% *Friday October 4, 2019 (lessons 9-10):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (2)* * Layout of the Butterfly network * the Wise layout * the Even & Even layout * comparison between the two methods * Layout of the Hypercube network * Collinear layout * general layout * The 3D layout problem %GREEN% *Wednesday October 9, 2019 (lessons 11-13):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem* * The problem * worms * damages caused by worms * Model of the problem on graphs: minimum vertex cover * definition * ILP model * a 2-approximation algorithm * independent set and maximum matching in relation with vertex cover * another approximation algorithm * Konig-Egevary theorem %GREEN% *Friday October 11, 2019 (lessons 14-15):* %ENDCOLOR% *The Problem of Minimizing Boolean Circuits i.e. the Minimum Set Covering Problem* * The problem of minimizing boolean functions * Model of the problem on graphs: the Minimum Set Cover Problem * definition * ILP formulation * relation with the Minimum Vertex Covering Problem * an O(log n)-approximation algorithm * another approximation algorithm * some related problems: * Hitting set problem * Edge Cover problem * Set Packing problem * Exact Cover problem *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems %GREEN% *Wednesday October 16, 2019 (lessons 16-18):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2)* * Direct and hidden collisions, interference graph * L(h,k)-labeling and minimum span (1) * The special case h=k in relation to the suqre of a graph * Properties of the L(h,k)-labeling and their proofs * Proof of NP-completeness for diameter 2 graphs %GREEN% *Friday October 18, 2019 (lessons 19-20):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (3)* * L(h,k)-labeling and minimum span (2) * Lower bound of Delta+1 on lambbda * Example: a graph requiring lambda=Delta squared - Delta * Upper bound of Delta squared + 2 Delta * Griggs and Yeh's conjecture * Exact results: cliques * Exact results: stars * Exact results: trees * Exact results: paths * Exact results: cycles * Approximate results: outerplanar graphs %GREEN% *Wednesday October 23, 2019 (lessons 21-23):* %ENDCOLOR% Lesson cancelled (due to illness of the teacher) %GREEN% *Friday October 25, 2019 (lessons 24-25):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (4)* * Variations of the problem * oriented L(2,1)-labeling * L(h1, ..., hk)-labeling * backbone coloring * multiple L(h,k)-labeling * frequency assignment in GSM networks * a parenthesis on the 4 color theorem *The minimum energy broadcast i.e. the minimum spanning tree (1)* * the Min Broadcast problem * NP-completeness and inapproximability results (reduction from Min Set Cover) * Relation between Min Broadcast and Min Spanning Tree (MST) %GREEN% *Wednesday October 29, 2019 (lessons 26-28):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (2)* * The MST problem * Kruskal algorithm * Prim algorithm * Boruvka algorithm * the Min Broadcast broblem * MST euristic * SPT euristic * BAIP euristic * approximation ratio for SPT %GREEN% *Friday November 1, 2019 (lessons 26-27):* %ENDCOLOR% Holiday %GREEN% *Wednesday November 6, 2019 (lessons 28-30):* %ENDCOLOR% Midterm Exam %GREEN% *Friday November 8, 2019 (lessons 31-32):* %ENDCOLOR% *The data mule problem i.e. the TSP* * (Fixed) sensor networks * The Data Mule problem * The TSP * NP-completeness * inapproximability * special cases: metric TSP and Euclidean TSP * generalizations %GREEN% *Wednesday November 13, 2019 (lessons 33-35):* %ENDCOLOR% *Student Lessons with the presence of the teacher (1)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (1)* * (mobile) sensor networks * the problem of centralized deployment * the problem on graphs: min weight matching in a bipartite graphs %GREEN% *Friday November 15, 2019 (lessons 36-37):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (2)* * maximum matching in a bipartite graph * P. Hall theorem (with proof) * corollary to the P. Hall theorem * searching an augmenting path * Berge theorem on the augmenting paths * algorithm based on Berge theorem * Hopcroft & Karp algorithm * Minimum weight perfect matching in bipartite graphs * augmenting paths * an algorithm based on searching augmenting paths * ILP formulation %GREEN% *Wednesday November 20, 2019 (lessons 38-40):* %ENDCOLOR% *Student Lessons with the presence of the teacher (2)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (3)* * Maximum matching in general graphs * blossoms * lemma on the cycle contraction * Edmonds algorithm (idea) *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (1)* * The problem * A Possible Approach: Virtual Forces * A Protocol Based on Voronoi Diagrams %GREEN% <b>Friday November 22, 2019 (lessons 41-42):* </b>%ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (2) * Voronoi Diagrams * hypthesis of general position * properties * complexity * the dual problem: Delaunay triangulation * Algorithms to compute the Voronoi diagram (1) * half-plane intersection (divide et impera) %GREEN% *Wednesday November 27, 2019 (lessons 43-45):* %ENDCOLOR% *Student Lessons with the presence of the teacher (3)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti *EVALUATION OF THE COURSE* %GREEN% *Friday November 29, 2019 (lessons 46-47):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (3)* * Algorithms to compute the Voronoi diagram (2) * Fortune algorithm * Heterogeneous sensors * A new notion of distance: Laguerre distance * Voronoi-Laguerre diagrams * A protocol based on Voronoi-Laguerre distance %GREEN% *Wednesday December 4, 2019 (lessons 48-50):* %ENDCOLOR% *Student Lessons with the presence of the teacher (4)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti *Monitoring by UAVs i.e. what? (some theses' proposals)* %GREEN% *Friday December 6, 2019 (lessons 51-52):* %ENDCOLOR% *Some problems in (co-)phylogeny (some further theses' proposals)* %GREEN% *Wednesday December 11, 2019 (lessons 51-53):* %ENDCOLOR% *Student Lessons with the presence of the teacher (5)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti %RED% Winner Announcement: Award for the best students' lesson%ENDCOLOR% %GREEN% *Friday December 13, 2019 (lessons 53-54):* %ENDCOLOR% *Phylogenetic Networks* by Prof. B. Sinaimeri (INRIA Grenoble) %GREEN% *Wednesday December 18, 2019 (lessons 55-57):* %ENDCOLOR% Midterm Exam ---++ <font color="red" size="+3">Lesson Diary A.y. 2018-2019</font> %RED% *Tuesday September 25, 2018 (Lessons 1-2,5):* %ENDCOLOR% *Introduction* *The Routing Problem i.e. the Shortest Path Problem (1)* * The routing Problem * The shortest path Problem (1) * shortest paths: BFS * the negative cycle issue * least cost paths: introduction %RED% *Thursday September 27, 2018 (Lessons 2,5-5):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (2)* * The shortest path Problem (2) * least cost paths (cnt.d): * Bellman-Ford algorithm * Dijkstra algorithm * Floyd-Warshall algorithm * The Routing Problem on Interconnection Topologies (1) * the packet switching model * the Butterfly network * routing on the Butterfly network: the greedy algorithm * the concept of blocking network, non-blocking network and rearrangeable network %RED% *Tuesday October 2, 2018 (Lessons 5-7,5):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (3)* * The Routing Problem on Interconnection Topologies (2) * the Benes network * routing on the Benes network: the looping algorithm *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (1)* * The Thompson model * The orthogonal grid drawing of graphs * Collinear Layout of the Complete network * Layout of the Complete network %RED% *Thursday October 4, 2018 (lessons 7,5-10):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (2)* * Relation between bisection width and layout area * Layout of the Butterfly network (1) * the Wise layout * the Even & Even layout * comparison between the two methods %RED% *Tuesday October 9, 2018 (lessons 10-12,5):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (3)* * Layout of the Hypercube network * Collinear layout * general layout * The 3D layout problem *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (1)* * The problem * worms * damages caused by worms * Model of the problem on graphs: minimum vertex cover (1) * definition * ILP model %RED% *Thursday October 11, 2018 (lessons 12,5-15):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (2)* * Model of the problem on graphs: minimum vertex cover (2) * a 2-approximation algorithm * independent set and maximum matching in relation with vertex cover * another approximation algorithm * Konig-Egevary theorem %RED% *Tuesday October 16, 2018 (lessons 15-17,5):* %ENDCOLOR% *The Problem of Minimizing Boolean Circuits i.e. the Minimum Set Covering Problem* * The problem of minimizing boolean functions * Model of the problem on graphs: the Minimum Set Cover Problem * definition * ILP formulation * relation with the Minimum Vertex Covering Problem * an O(log n)-approximation algorithm * another approximation algorithm * some related problems: * Hitting set problem * Edge Cover problem * Set Packing problem * Exact Cover problem *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems %RED% *Thursday October 18, 2018 (lessons 17,5-20):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2)* * Direct and hidden collisions, interference graph * L(h,k)-labeling and minimum span (1) * The special case h=k in relation to the square of a graph * Properties of the L(h,k)-labeling and their proofs * Proof of NP-completeness for diameter 2 graphs %BLUE% *Tuesday October 23, 2018 (lessons 20-22,5):* %ENDCOLOR% *Student Lessons with the presence of the teacher (1)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti %RED% *Thursday October 25, 2018 (lessons 22,5-25):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (3)* * L(h,k)-labeling and minimum span (2) * Lower bound of Delta+1 on lambbda * Example: a graph requiring lambda=Delta squared - Delta * Upper bound of Delta squared + 2 Delta * Griggs and Yeh's conjecture * Exact results: cliques * Exact results: stars * Exact results: trees * Exact results: paths * Exact results: cycles %RED% *Tuesday October 30, 2018:* %ENDCOLOR% Lesson canceled by the Dean. %RED% *Thursday November 1, 2018:* %ENDCOLOR% Holiday. %RED% *Tuesday November 6, 2018 (lessons 25-27,5):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (4)* * L(h,k)-labeling and minimum span (3) * Approximate results: outerplanar graphs * variations of the problem * oriented L(2,1)-labeling * L(h1, ..., hk)-labeling * backbone coloring * multiple L(h,k)-labeling * frequency assignment in GSM networks * a parenthesis on the 4 color theorem *The minimum energy broadcast i.e. the minimum spanning tree (1)* * the Min Broadcast problem * NP-completeness and inapproximability results (reduction from Min Set Cover) * Relation between Min Broadcast and Min Spanning Tree (MST) %BLUE% *Thursday November 8, 2018 (lessons 27,5-30):* %ENDCOLOR% *Mid term exam* %BLUE% *Tuesday November 13, 2018 (lessons 30-32,5):* %ENDCOLOR% *Student Lessons with the presence of the teacher (2)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti %RED% *Thursday November 15, 2018 (lessons 32,5-35):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (2)* * The MST problem * Kruskal algorithm * Prim algorithm * Boruvka algorithm * the Min Broadcast broblem * MST euristic * SPT euristic * BAIP euristic * approximation ratio for SPT %RED% *Tuesday November 20, 2018 (lessons 35-37,5):* %ENDCOLOR% *The data mule problem i.e. the TSP* * (Fixed) sensor networks * The Data Mule problem * The TSP * NP-completeness * inapproximability * special cases: metric TSP and Euclidean TSP * generalizations %RED% *Thursday November 22, 2018 (lessons 37,5-40):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (1)* * (mobile) sensor networks * the problem of centralized deployment * the problem on graphs: min weight matching in a bipartite graphs * maximum matching in a bipartite graph * P. Hall theorem (with proof) * corollary to the P. Hall theorem * searching an augmenting path * Berge theorem on the augmenting paths * algorithm based on Berge theorem * Hopcroft & Karp algorithm %RED% *Tuesday November 27, 2018:* %ENDCOLOR% *NO LESSON* %RED% *Thursday November 29, 2018 (lessons 40-42,5):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (2)* * Minimum weight perfect matching in bipartite graphs * augmenting paths * an algorithm based on searching augmenting paths * ILP formulation * Maximum matching in general graphs * blossoms * lemma on the cycle contraction * Edmonds algorithm (idea) *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (1)* * The problem * A Possible Approach: Virtual Forces * A Protocol Based on Voronoi Diagrams *EVALUATION OF THE COURSE* %RED% *Tuesday December 4, 2018 (lessons 42,5-45):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (2)* * Voronoi Diagrams * hypthesis of general position * properties * complexity * the dual problem: Delaunay triangulation * Algorithms to compute the Voronoi diagram * half-plane intersection (divide et impera) * Fortune's algorithm %GREEN% *Thursday December 6, 2018 (lessons 45-47,5):* %ENDCOLOR% *Distributed Deployment 2* %BLUE% *Tuesday December 11, 2018 (lessons 47,5-50):* %ENDCOLOR% *Student Lessons with the presence of the teacher (3)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti %GREEN% *Thursday December 13, 2018 (lessons 50-52,5):* %ENDCOLOR% *UAVs 1* %BLUE% *Tuesday December 18, 2018 (lessons 52,5-55):* %ENDCOLOR% *UAVs 2 (Prof. S. Silvestri - University of Kentucky Computer Science)* %BLUE% *Tuesday December 20, 2018 (lessons 55-57,5):* %ENDCOLOR% *Student Lessons with the presence of the teacher (4)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti ---+++ <font color="blue" size="+3">Lesson Diary A.y. 2017-2018</font> %BLUE% *Friday September 29, 2017 (Lessons 1-2,5):* %ENDCOLOR% *Introduction* *The Routing Problem i.e. the Shortest Path Problem (1)* * The routing Problem * The shortest path Problem (1) * shortest paths: BFS * the negative cycle issue * least cost paths: introduction %BLUE% *Monday October 2, 2017 (Lessons 2,5-5):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (2)* * The shortest path Problem (2) * least cost paths (cnt.d): * Bellman-Ford algorithm * Dijkstra algorithm * Floyd-Warshall algorithm * The Routing Problem on Interconnection Topologies (1) * the packet switching model * the Butterfly network * routing on the Butterfly network: the greedy algorithm * the concept of blocking network, non-blocking network and rearrangeable network * the Benes network %BLUE% *Friday October 6, 2017 (Lessons 5-7,5):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (3)* * The Routing Problem on Interconnection Topologies (2) * routing on the Benes network: the looping algorithm *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (1)* * The Thompson model * The orthogonal grid drawing of graphs * Collinear Layout of the Complete network * Layout of the Complete network %BLUE% *Monday October 9, 2017 (lessons 7,5-10):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (2)* * Layout of the Butterfly network (1) * the Wise layout * the Even & Even layout * comparison between the two methods %BLUE% *Friday October 13, 2017 (lessons 10-12,5):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (3)* * Layout of the Hypercube network * Collinear layout * general layout * The 3D layout problem %BLUE% *Monday October 16, 2017 (lessons 12,5-15):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem* * The problem * worms * damages caused by worms * Model of the problem on graphs: minimum vertex cover * definition * ILP model * a 2-approximation algorithm * independent set and maximum matching in relation with vertex cover * another approximation algorithm * Konig-Egevary theorem *The Problem of Minimizing Boolean Circuits i.e. the Minimum Set Covering Problem (1)* * The problem of minimizing boolean functions * Model of the problem on graphs: the Minimum Set Covering Problem * definition * ILP formulation * relation with the Minimum Vertex Covering Problem * an O(log n)-approximation algorithm %BLUE% *Friday October 20, 2017 (lessons 15-17,5):* %ENDCOLOR% *The Problem of Minimizing Boolean Circuits i.e. the Minimum Set Covering Problem (2)* * * another approximation algorithm * some related problems * Hitting set problem * Edge Cover problem * Set Packing problem * Exact Cover problem *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems * Direct and hidden collisions, interference graph * L(h,k)-labeling and minimum span * The special case h=k in relation to the suqre of a graph * Properties of the L(h,k)-labeling and their proofs %BLUE% *Monday October 23, 2017 (lessons 17.5-20):* %ENDCOLOR% *Student Lessons with the presence of the teacher (1)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti %BLUE% *Friday October 27, 2017 (lessons 20-22.5):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2)* * * Proof of NP-completeness for diameter 2 graphs * Lower bound of Delta+1 on lambbda * Example: a graph requiring lambda=Delta squared - Delta * Upper bound of Delta squared + 2 Delta * Griggs and Yeh's conjecture * Exact results: cliques * Exact results: stars * Exact results: trees * Exact results: paths * Exact results: cycles * Approximate results: outerplanar graphs %BLUE% *Monday October 30, 2017 (lessons 22.5-25):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (3)* * variations of the problem: * oriented L(2,1)-labeling * L(h1, ..., hk)-labeling * backbone coloring * multiple L(h,k)-labeling * frequency assignment in GSM networks * a parenthesis on the 4 color theorem *The minimum energy broadcast i.e. the minimum spanning tree (1)* * the Min Broadcast problem * NP-completeness and inapproximability results (reduction from Min Set Cover) * Relation between Min Broadcast and Min Spanning Tree (MST) %BLUE% *Friday November 3, 2017 (lessons 25-27.5):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (2)* * The MST problem * Kruskal algorithm * Prim algorithm * Boruvka algorithm * the Min Broadcast broblem * MST euristic * SPT euristic * BAIP euristic * approximation ratio for SPT %BLUE% *Monday November 6, 2017 (lessons 27.5-30):* %ENDCOLOR% *The data mule problem i.e. the TSP* * (Fixed) sensor networks * The Data Mule problem * The TSP * NP-completeness * inapproximability * special cases: metric TSP and Euclidean TSP * generalizations %BLUE% *Friday November 10, 2017 (lessons 30-32.5):* %ENDCOLOR% Attendance at the Workshop in honour of Janos Korner (both students and teacher) %BLUE% *Monday November 13, 2017 (lessons 32.5-35):* %ENDCOLOR% *Student Lessons with the presence of the teacher (2)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti %BLUE% *Friday November 17, 2017 (lessons 35-37.5):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (1)* * (mobile) sensor networks * the problem of centralized deployment * the problem on graphs: min weight matching in a bipartite graphs * maximum matching in a bipartite graph * P. Hall theorem (with proof) * corollary to the P. Hall theorem * searching an augmenting path * Berge theorem on the augmenting paths * algorithm based on Berge theorem * Hopcroft & Karp algorithm %BLUE% *Monday November 20, 2017 (lessons 37.5-40):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (2)* * Minimum weight perfect matching in bipartite graphs * augmenting paths * an algorithm based on searching augmenting paths * ILP formulation * Maximum matching in general graphs * blossoms * lemma on the cycle contraction * Edmonds algorithm (idea) *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (1)* * The problem * A Possible Approach: Virtual Forces *EVALUATION OF THE COURSE* %BLUE% *Friday November 24, 2017 (lessons 40-42.5):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (2)* * A Protocol Based on Voronoi Diagrams * Voronoi Diagrams * hypthesis of general position * properties * complexity * the dual problem: Delaunay triangulation * Algorithms to compute the Voronoi diagram * half-plane intersection (divide et impera) * Fortune's algorithm %BLUE% *Monday November 27, 2017 (lessons 42.5-45):* %ENDCOLOR% *Student Lessons with the presence of the teacher (3)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti %BLUE% *Friday December 1, 2017 (lessons 45-47.5):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (3)* * Heterogeneous sensors * A new notion of distance: Laguerre distance * Voronoi-Laguerre diagrams * A protocol based on Voronoi-Laguerre distance *Monitoring by UAVs i.e. What? (1)* Some theses proposals %BLUE% *Monday December 4, 2017 (lessons 47.5-50):* %ENDCOLOR% IT Meeting - http://www.studiareinformatica.uniroma1.it/38-it-meeting-lunedi-4-dicembre-2017 %BLUE% *Friday December 8, 2017:* %ENDCOLOR% *Holiday* %BLUE% *Monday December 11, 2017 (lessons 50-52.5):* %ENDCOLOR% *Monitoring by UAVs i.e. What? (2)* Some theses proposals *Some problems in (co-)Phylogeny* Some other theses proposals %BLUE% *Friday December 15, 2017 (lessons 52.5-55):* %ENDCOLOR% *Student Lessons with the presence of the teacher (4)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti %BLUE% *Monday December 18, 2017 (lessons 55-57.5):* %ENDCOLOR% *Student Lessons with the presence of the teacher (5)* see http://twiki.di.uniroma1.it/twiki/view/Algoreti/ProgrammaLezioniDegliStudenti %BLUE% *Friday December 22, 2017 (lessons 57.5-60):* %ENDCOLOR% *Mid term exam* ---+++ <font color="blue" size="+3">Previous years' Diaries</font> ---+++ <font color="blue" size="+2">Lesson Diary A.y. 2016-2017</font> %BLUE% *Monday September 26, 2016 (Lessons 1-2):* %ENDCOLOR% *Introduction* *The Routing Problem i.e. the Shortest Path Problem (1)* * The routing Problem * The shortest path Problem (1) * shortest paths: BFS * the negative cycle issue * least cost paths: introduction * Bellman-Ford algorithm %BLUE% *Friday September 30, 2016 (Lessons 3-4):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (2)* * The shortest path Problem (2) * least cost paths (cnt.d): * Dijkstra algorithm * Floyd-Warshall algorithm * The Routing Problem on Interconnection Topologies (1) * the packet switching model * the Butterfly network %BLUE% *Monday October 3, 2016 (Lessons 5-6):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (3)* * The Routing Problem on Interconnection Topologies (2) * routing on the Butterfly network: the greedy algorithm * the concept of blocking network, non-blocking network and rearrangeable network * the Benes network * routing on the Benes network: the looping algorithm *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (1)* * The Thompson model * The orthogonal grid drawing of graphs * Collinear Layout of the Complete network * Layout of the Complete network %BLUE% *Friday October 7, 2016 (lessons 7-8):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (2)* * Layout of the Butterfly network (1) * the Wise layout * the Even & Even layout * comparison between the two methods %BLUE% *Monday October 10, 2016 (lessons 9-10):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (3)* * Layout of the Butterfly network (2) * Optimal area Layout of the Butterfly * Layout of the Hypercube network * Collinear layout * general layout * The 3D layout problem %BLUE% *Friday October 14, 2016 (lessons 11-12):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (1)* * The problem * worms * damages caused by worms * Model of the problem on graphs: minimum vertex cover * definition * ILP model * a 2-approximation algorithm * independent set and maximum matching in relation with vertex cover * another approximation algorithm %BLUE% *Monday October 17, 2016 (lessons 13-14):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (2)* * minimum vertex cover (cntd) * Konig-Egevary theorem *The Problem of Minimizing Boolean Circuits i.e. the Minimum Set Covering Problem (1)* * The problem of minimizing boolean functions * Model of the problem on graphs: the Minimum Set Covering Problem * definition * ILP formulation * relation with the Minimum Vertex Covering Problem * an O(log n)-approximation algorithm * another approximation algorithm %BLUE% *Friday October 21, 2016 (lessons 15-16):* %ENDCOLOR% *The Problem of Minimizing Boolean Circuits i.e. the Minimum Set Covering Problem (2)* * * some related problems * Hitting set problem * Edge Cover problem * Set Packing problem * Exact Cover problem *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems * Direct and hidden collisions, interference graph %BLUE% *Monday October 24, 2016 (lessons 17-18):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2)* * L(h,k)-labeling and minimum span * The special case h=k in relation to the suqre of a graph * Properties of the L(h,k)-labeling and their proofs * Proof of NP-completeness for diameter 2 graphs * Lower bound of Delta+1 on lambbda * Exemple: a graph requiring lambda=Delta squared - Delta %BLUE% *Friday October 28, 2016 (lessons 19-20):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (3)* * L(h,k)-labeling and minimum span (cntd) * Upper bound of Delta squared + 2 Delta * Griggs and Yeh's conjecture * Exact results: cliques * Exact results: stars * Exact results: trees * Exact results: paths * Exact results: cycles * Approximate results: outerplanar graphs (part) %BLUE% *Monday October 31, 2016 (lessons 21-22):* %ENDCOLOR% No lessons, due to security check after the earthquacke of October 30. %BLUE% *Friday November 4, 2016 (lessons 23-24):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (4)* * L(h,k)-labeling and minimum span (cntd) * Approximate results: outerplanar graphs (part) * variations of the problem: * oriented L(2,1)-labeling * L(h1, ..., hk)-labeling * backbone coloring * multiple L(h,k)-labeling * frequency assignment in GSM networks * a parenthesis on the 4 color theorem %BLUE% *Monday November 7, 2016 (lessons 25-26):* %ENDCOLOR% Mid term evaluation (part 1). %BLUE% *Friday November 11, 2016 (lessons 27-28):* %ENDCOLOR% Mid term evaluation (part 2). %BLUE% *Monday November 14, 2016 (lessons 29-30):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (1)* * the Min Broadcast problem * NP-completeness and inapproximability results (reduction from Min Set Cover) * Relation between Min Broadcast and Min Spanning Tree (MST) %BLUE% *Friday November 18, 2016 (lessons 31-32):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (2)* * The MST problem * Kruskal algorithm * Prim algorithm * Boruvka algorithm * the Min Broadcast broblem * MST euristic * SPT euristic * BAIP euristic * approximation ratio for SPT %BLUE% *Monday November 21, 2016 (lessons 33-34):* %ENDCOLOR% *The data mule problem i.e. the TSP* * (Fixed) sensor networks * The Data Mule problem * The TSP * NP-completeness * inapproximability * special cases: metric TSP and Euclidean TSP * generalizations %BLUE% *Friday November 25, 2016 (lessons 35-36):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (1)* * (mobile) sensor networks * the problem of centralized deployment * the problem on graphs: min weight matching in a bipartite graphs * maximum matching in a bipartite graph * P. Hall theorem (with proof) * corollary to the P. Hall theorem * searching an augmenting path * Berge theorem on the augmenting paths %BLUE% *Monday November 28, 2016 (lessons 37-38):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (2)* * * algorithm based on Berge theorem * Hopcroft & Karp algorithm * Minimum weight perfect matching in bipartite graphs * augmenting paths * an algorithm based on searching augmenting paths * ILP formulation * Maximum matching in general graphs * blossoms * lemma on the cycle contraction * Edmonds algorithm (idea) %BLUE% *Friday December 2, 2016 (lessons 39-40):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (1)* * The problem * A Possible Approach: Virtual Forces * A Protocol Based on Voronoi Diagrams * Voronoi Diagrams * hypthesis of general position * properties * complexity * the dual problem: Delaunay triangulation * Algorithms to compute the Voronoi diagram * half-plane intersection (divide et impera) %BLUE% *Monday December 5, 2016 (lessons 41-42):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (2)* * Algorithms to compute the Voronoi diagram (cntd) * Fortune's algorithm * Heterogeneous sensors * A new notion of distance: Laguerre distance * Voronoi-Laguerre diagrams * A protocol based on Voronoi-Laguerre distance %BLUE% *Friday December 9, 2016 (lessons 43-44):* %ENDCOLOR% *No lesson: the building is closed* %BLUE% *Monday December 12, 2016 (lessons 45-46):* %ENDCOLOR% *Student lessons* %BLUE% *Friday December 16, 2016 (lessons 47-48):* %ENDCOLOR% *IT meeting* %BLUE% *Monday December 19, 2016 (lessons 49-50):* %ENDCOLOR% *Student lessons* %BLUE% *Tuesday December 20, 2016 (lessons 51-52):* %ENDCOLOR% *Student lessons* ---+++ <font color="blue" size="+2">Lesson Diary A.y. 2015-2016</font> %BLUE% *Tuesday September 22, 2015 (Lessons 1-2):* %ENDCOLOR% *Introduction* *The Routing Problem i.e. the Shortest Path Problem (1)* * The routing Problem * The shortest path Problem (1) * shortest paths: BFS * the negative cycle issue * least cost paths: introduction %BLUE% *Friday September 25, 2015 (Lessons 3-4):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (2)* * The shortest path Problem (2) * least cost paths (cnt.d): * Bellman-Ford algorithm * Dijkstra algorithm * Floyd-Warshall algorithm * The Routing Problem on Interconnection Topologies (1) * the packet switching model * the Butterfly network * routing on the Butterfly network: the greedy algorithm %BLUE% *Tuesday September 29, 2015 (Lessons 5-6):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (3)* * The Routing Problem on Interconnection Topologies (2) * the concept of blocking network, non-blocking network and rearrangeable network * the Benes network * routing on the Benes network: the looping algorithm *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (1)* * The Thompson model * The orthogonal grid drawing of graphs * Collinear Layout of the Complete network %BLUE% *Friday October 2, 2015 (lessons 7-8):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (2)* * Layout of the Complete network * Layout of the Butterfly network * the Wise layout %BLUE% *Friday October 2, 2015 (lessons 9-10):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (3)* * Layout of the Butterfly network (3) * the Even & Even layout * comparison between the two methods %BLUE% *Tuesday October 6, 2015 (lessons 11-12):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (4)* * Layout of the Butterfly network (4) * Optimal area Layout of the Butterfly * Layout of the Hypercube network * The 3D layout problem %BLUE% *Tuesday October 9, 2015 (lessons 13-14):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (1)* * The problem * worms * damages caused by worms * Model of the problem on graphs: minimum vertex cover * definition * ILP model * a 2-approximation algorithm * independent set and maximum matching in relation with vertex cover %BLUE% *Tuesday October 13, 2015 (lessons 15-16):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (2)* * minimum vertex cover (cntd) * another approximation algorithm * Konig-Egevary theorem *The Problem of Minimizing Boolean Circuits i.e. the Minimum Set Covering Problem* * The problem of minimizing boolean functions * Model of the problem on graphs: the Minimum Set Covering Problem * definition * ILP formulation * relation with the Minimum Vertex Covering Problem * an O(log n)-approximation algorithm * another approximation algorithm * some related problems * Hitting set problem * Edge Cover problem * Set Packing problem * Exact Cover problem %BLUE% *Tuesday October 20, 2015 (lessons 17-18):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems * Direct and hidden collisions, interference graph * L(h,k)-labeling and minimum span * The special case h=k in relation to the suqre of a graph * Properties of the L(h,k)-labeling and their proofs * Proof of NP-completeness for diameter 2 graphs %BLUE% *Friday October 23, 2015 (lessons 19-20):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2)* * L(h,k)-labeling and minimum span (cntd.) * Lower bound of Delta+1 on lambbda * Exemple: a graph requiring lambda=Delta squared - Delta * Upper bound of Delta squared + 2 Delta * Griggs and Yeh's conjecture * Exact results: cliques * Exact results: stars * Exact results: trees * Exact results: paths * Exact results: cycles %BLUE% *Tuesday October 27, 2015 (lessons 21-22):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (3)* * L(h,k)-labeling and minimum span (cntd.) * Approximate results: outerplanar graphs * variations of the problem: * oriented L(2,1)-labeling * L(h1, ..., hk)-labeling * backbone coloring * multiple L(h,k)-labeling * frequency assignment in GSM networks * a parenthesis on the 4 color theorem %BLUE% *Friday October 30, 2015 (lessons 23-24):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (1)* * the MinBroadcast problem * NP-completeness and inapproximability results (reduction from MinSetCover) * Relation between MinBroadcast and MinSpanningTree %BLUE% *Friday November 6, 2015:* %ENDCOLOR% Mid term exam %BLUE% *Tuesday November 10, 2015 (lessons 25-26):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (2)* * the Min Broadcast broblem * MST euristic * SPT euristic * BAIP euristic * approximation ratio for SPT %BLUE% *Friday November 13, 2015 (lessons 27-28):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (1)* * the problem of centralized deployment * the problem on graphs: min weight matching in a bipartite graphs * maximum matching in a bipartite graph * P. Hall theorem (with proof) * corollary to the P. Hall theorem * searching an augmenting path * Berge theorem on the augmenting paths %BLUE% *Tuesday November 17, 2015 (lessons 29-30):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (2)* * * algorithm based on Berge theorem * Hopcroft & Karp algorithm * Minimum weight perfect matching in bipartite graphs * augmenting paths * an algorithm based on searching augmenting paths * ILP formulation * Maximum matching in general graphs * blossoms * lemma on the cycle contraction * Edmonds algorithm (idea) %BLUE% *Friday November 20, 2015 (lessons 31-32):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (1)* * The problem * A Possible Approach: Virtual Forces * A Protocol Based on Voronoi Diagrams * Voronoi Diagrams * hypthesis of general position * properties * complexity * the dual problem: Delaunay triangulation * Algorithms to compute the Voronoi diagram * half-plane intersection (divide et impera) %BLUE% *Tuesday November 24, 2015 (lessons 33-34):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (2)* * Algorithms to compute the Voronoi diagram (cntd) * Fortune's algorithm * Heterogeneous sensors * A new notion of distance: Laguerre distance * Voronoi-Laguerre diagrams * A protocol based on Voronoi-Laguerre distance ---+++ <font color="blue" size="+2">Lesson Diary A.y. 2014-2015</font> %RED% *Tuesday September 29, 2014 (Lessons 1-2):* %ENDCOLOR% *Introduction* *The Routing Problem i.e. the Shortest Path Problem (1)* * The routing Problem * The shortest path Problem (1) * shortest paths: BFS * least cost paths: introduction %RED% *Friday October 3, 2014 (Lessons 3-4):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (2)* * The shortest path Problem (2) * least cost paths (cnt.d): * Bellman-Ford algorithm * Dijkstra algorithm * Floyd-Warshall algorithm * The Routing Problem on Interconnection Topologies (1) * the packet switching model * the Butterfly network * routing on the Butterfly network: the greedy algorithm %RED% *Tuesday October 7, 2014 (Lessons 5-6):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (3)* * The Routing Problem on Interconnection Topologies (2) * the concept of blocking network, non-blocking network and rearrangeable network * the Benes network * routing on the Benes network: the looping algorithm *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (1)* * The Thompson model * The orthogonal grid drawing of graphs * Layout of the Butterfly network (1) %RED% *Friday October 10, 2014 (lessons 7-8):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (2)* * Layout of the Butterfly network (2) * the Wise layout * the Even & Even layout * comparison between the two methods %RED% *Tuesday October 14, 2014 (lessons 9-10):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (3)* * Layout of the Butterfly network (3) * Optimal area Layout of the Butterfly * Layout of the Hypercube network * The 3D layout problem %RED% *Tuesday October 17, 2014 (lessons 11-12):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (1)* * The problem * worms * damages caused by worms * Model of the problem on graphs: minimum vertex cover * definition * ILP model * a 2-approximation algorithm * independent set in relation with vertex cover %RED% *Tuesday October 21, 2014 (lessons 13-14):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (2)* * minimum vertex cover (cnt.d) * matching in relation with vertex cover * another approximation algorithm * Konig-Egevary theorem *The Problem of Minimizing Boolean Circuits i.e. the Minimum Set Covering Problem* * The problem of minimizing boolean functions * Model of the problem on graphs: the Minimum Set Covering Problem * definition * ILP formulation * relation with the Minimum Vertex Covering Problem * an O(log n)-approximation algorithm * another approximation algorithm * some related problems * Hitting set problem * Edge Cover problem * Set Packing problem * Exact Cover problem %RED% *Friday October 24, 2014:* %ENDCOLOR% *No lesson because of bus and train strike* %RED% *Tuesday October 28, 2014 (lessons 15-16):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems * Direct and hidden collisions, interference graph * L(h,k)-labeling and minimum bandwidth * The special case h=k in relation to the suqre of a graph * Properties of the L(h,k)-labeling and their proofs %RED% *Friday October 31, 2014 (lessons 17-18):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2)* * L(h,k)-labeling and minimum bandwidth (cntd.) * Proof of NP-completeness for diameter 2 graphs * Lower bound of Delta+1 on lambbda * Exemple: a graph requiring lambda=Delta squared - Delta * Upper bound of Delta squared + 2 Delta * Griggs and Yeh's conjecture * Exact results: cliques * Exact results: stars * Exact results: trees %RED% *Tuesday November 4, 2014 (lessons 19-20):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (3)* * L(h,k)-labeling and minimum bandwidth (cntd.) * Exact results: paths * Exact results: cycles * Approximate results: outerplanar graphs * variations of the problem: * oriented L(2,1)-labeling * L(h1, ..., hk)-labeling * backbone coloring * multiple L(h,k)-labeling %RED% *Friday November 7, 2014 (lessons 21-22):* %ENDCOLOR% Mid term exam %RED% *Tuesday November 11, 2014 (lessons 23-24):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (4)** variations of the problem (cnt.d): * * frequency assignment in GSM networks * a parenthesis on the 4 color theorem *The minimum energy broadcast i.e. the minimum spanning tree (1)* * the MinBroadcast problem * NP-completeness and inapproximability results (reduction from MinSetCover) * Relation between MinBroadcast and MinSpanningTree %RED% *Friday November 14, 2014 (lessons 25-26):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (2)* * the Min Broadcast broblem * MST euristic * SPT euristic * BAIP euristic %RED% *Tuesday November 18, 2014 (lessons 27-28):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (3)* * the Min Broadcast broblem (cnt.d) * approximation ratio for SPT *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (1)* * the problem of centralized deployment * Ithe problem on graphs: min weight matching in a bipartite graphs * maximum matching in a bipartite graph * P. Hall theorem (with proof) * corollary to the P. Hall theorem %RED% *Friday November 21, 2014 (lessons 29-30):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (2)* * Maximum matching in bipartite graphs * searching an augmenting path * Berge theorem on the augmenting paths * algorithm based on Berge theorem * Hopcroft & Karp algorithm * Minimum weight perfect matching in bipartite graphs * augmenting paths * an algorithm based on searching augmenting paths * ILP formulation * Maximum matching in general graphs * blossoms * lemma on the cycle contraction * Edmonds algorithm (idea) %RED% *Tuesday November 25, 2014 (lessons 31-32):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (1)* * The problem * A Possible Approach: Virtual Forces * A Protocol Based on Voronoi Diagrams * Voronoi Diagrams * hypthesis of general position * properties * complexity * the dual problem: Delaunay triangulation * Algorithms to compute the Voronoi diagram * half-plane intersection (divide et impera) *Friday November 28, 2014 (lessons 33-34):* *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (2)* * Algorithms to compute the Voronoi diagram (cnt.d) * Fortune's algorithm * Heterogeneous sensors * A new notion of distance: Laguerre distance %RED% *Tuesday December 2, 2014 (lessons 35-36):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (3)* * Voronoi-Laguerre diagrams * A protocol based on Voronoi-Laguerre distance %RED% *Friday December 5, 2014 (lessons 37-38):* %ENDCOLOR% *Student lessons (1)* %RED% *Tuesday December 9, 2014 (lessons 39-40):* %ENDCOLOR% *Student lessons (2)* %RED% *Tuesday December 16, 2014 (lessons 41-42):* %ENDCOLOR% *Student lessons (3)* ---++ <font color="blue" size="+2">Lesson Diary A.y. 2013-2014</font> %RED% *Monday September 30, 2013 (Lessons 1-2):* %ENDCOLOR% *Introduction* *The Routing Problem i.e. the Shortest Path Problem (1)* * The routing Problem * The shortest path Problem (1) * shortest paths: BFS * least cost paths: * Bellman-Ford algorithm * Dijkstra algorithm %RED% *Friday October 4, 2013 (lessons 3-4):* %ENDCOLOR% *The Routing Problem i.e. the Shortest Path Problem (2)* * The shortest path Problem (2) * least cost paths (cntd.): * Floyd-Warshall algorithm * The Routing Problem on Interconnection Topologies * the packet switching model * the Butterfly network * routing on the Butterfly network: the greedy algorithm * the concept of blocking network, non-blocking network and rearrangeable network * the Benes network * routing om the Benes network: the looping algorithm %RED% *Monday October 7, 2013 (lessons 5-6):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (1)* * The Thompson model * The orthogonal grid drawing of graphs * Layout of the Butterfly network (1) * the Wise layout * the Even & Even layout %RED% *Friday October 11, 2013 (lessons 7-8):* %ENDCOLOR% *The Problem of Laying out Interconnection Topologies i.e. the Grid Orthogonal Drawing Problem (2)* * Layout of the Butterfly network (2) * Overview of other results * Optimal area Layout of the Butterfly * Layout of the Hypercube network * The 3D layut problem %RED% *Monday October 14, 2013 (lessons 9-10):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (1)* * The problem * worms * damages caused by worms * worm expansion * Model of the problem on graphs * minimum vertex cover * definition * ILP model * a 2-approximation algorithm * independent set in relation with vertex cover * matching in relation with vertex cover * another approximation algorithm %RED% *Friday October 18, 2013 (lessons 11-12):* %ENDCOLOR% *The problem of worm propagation/prevention i.e. the Minimum Vertex Covering Problem (2)* * minimum vertex cover (cntd.) * Konig-Egevary theorem *The Problem of Minimizing Boolean Circuits<span style="{encoded: 's1'};"> </span>i.e.<span style="{encoded: 's1'};"> </span>the Minimum<span style="{encoded: 's1'};"> </span>Set Covering Problem* * The problem of minimizing boolean functions * Its equivalence with the Minimum Set Covering Problem * the Minimum Set Covering Problem * definition * ILP formulation * relation with the Minimum Vertex Covering Problem * an O(log n)-approximation algorithm * another approximation algorithm * some related problems * Hitting set problem * Edge Cover problem * Set Packing problem * Exact Cover problem %RED% *Monday October 21, 2013 (lessons 13-14):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (1)* * Introduction to the frequency assignment problems * Direct and hidden collisions, interference graph * L(h,k)-labeling and minimum bandwidth * The special case h=k in relation to the suqre of a graph * Properties of the L(h,k)-labeling and their proofs * Proof of NP-completeness for diameter 2 graphs %RED% *Friday October 25, 2013 (lessons 15-16):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (2)* * L(h,k)-labeling and minimum bandwidth (cntd.) * Lower bound of Delta+1 on lambbda * Exemple: a graph requiring lambda=Delta squared - Delta * Upper bound of Delta squared + 2 Delta * Griggs and Yeh's conjecture * Exact results: cliques * Exact results: stars * Exact results: trees * Exact results: paths * Exact results: cycles %RED% *Monday October 28, 2013 (lessons 17-18):* %ENDCOLOR% *A Frequency assignment problem i.e. the L(h,k)-Labeling Problem (3)* * L(h,k)-labeling and minimum bandwidth (cntd.) * Approximate results: outerplanar graphs * variations of the problem: * oriented L(2,1)-labeling * L(h1, ..., hk)-labeling * backbone coloring * multiple L(h,k)-labeling * frequency assignment in GSM networks * a parenthesis on the 4 color theorem %RED% *Monday November 4, 2013 (lessons 19-20):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (1)* * the MinBroadcast problem * NP-completeness and inapproximability results (reduction from MinSetCover) * Relation between MinBroadcast and MinSpanningTree * the Minimum spanning tree problem * Kruskal algorithm * Prim algorithm * Boruvka algorithm %RED% *Friday November 8, 2013 (lessons 21-22):* %ENDCOLOR% *The minimum energy broadcast i.e. the minimum spanning tree (2)* * the Min Broadcast broblem * MST euristic * SPT euristic * BAIP euristic * approximation ratio for SPT *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (1)* * the problem of centralized deployment * Ithe problem on graphs: min weight matching in a bipartite graphs * maximum matching in a bipartite graph * P. Hall theorem (with proof) * corollary to the P. Hall theorem %BLUE% *week November 11-15: No classes - midterm exams* %ENDCOLOR% %RED% *Monday November 18, 2013 (lessons 23-24):* %ENDCOLOR% *The centralized deployment of Mobile sensors i.e. the perfect matching in Bipartite graphs (2)* * Maximum matching in bipartite graphs * searching an augmenting path * Berge theorem on the augmenting paths * algorithm based on Berge theorem * Hopcroft & Karp algorithm * Minimum weight perfect matching in bipartite graphs * augmenting paths * an algorithm based on searching augmenting paths * ILP formulation * Maximum matching in general graphs * blossoms * lemma on the cycle contraction * Edmonds algorithm %RED% *Friday November 22, 2013 (lessons 25-26):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (1)* * The problem * A Possible Approach: Virtual Forces * A Protocol Based on Voronoi Diagrams * Voronoi Diagrams * hypthesis of general position * properties * complexity * the dual problem: Delaunay triangulation * Algorithms to compute the Voronoi diagram * half-plane intersection (divide et impera) %RED% *Monday December 2, 2013 (lessons 27-28):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (2)* * Algorithms to compute the Voronoi diagram (cnt.d) * Fortune's algorithm %RED% *Friday December 6, 2013 (lessons 29-30):* %ENDCOLOR% *The Distributed Deployment of Sensors i.e. the Construction of a Voronoi Diagram (3)* * Heterogeneous sensors * A new notion of distance: Laguerre distance * Voronoi-Laguerre diagrams * A protocol based on Voroi-Laguerre distance %RED% *Monday December 9, 2013 (lessons 31-32):* %ENDCOLOR% Student Lessons %RED% *Friday December 13, 2013 (lessons 33-34):* %ENDCOLOR% Student Lessons %RED% *Monday December 16, 2013 (lessons 35-36):* %ENDCOLOR% Student Lessons ---++ <font color="blue" size="+2">Diario delle Lezioni A.A. 2012-2013</font> %RED% *Mercoledi' 3 Ottobre 2011 (Ore 1-2):* %ENDCOLOR% *Introduzione al Corso* *Il Problema dell'Instradamento<span style="{encoded: 's1'};"> </span>ovvero<span style="{encoded: 's1'};"> </span>il Cammino più Corto o di Costo minimo (1)* * Il problema dell'instradamento * Il problema del cammino di costo minimo * cammini piu' corti: visita in ampiezza * cammini minimi: * algoritmo di Bellman-Ford %RED% *Lunedi' 8 Ottobre 2012 (Ore 3-4):* %ENDCOLOR% *Il Problema dell'Instradamento ovvero il Cammino più Corto o di Costo minimo (2)* * * cammini minimi (segue): * algoritmo di Dijkstra * algoritmo di Floyd-Warshall * Instradamento sulle Topologie di Interconnessione * il modello di packet switching * la Butterfly * instradamento sulla Butterfly %RED% *Mercoledi' 10 Ottobre 2012 (Ore 5-6):* %ENDCOLOR% *Il Problema dell'Instradamento<span style="{encoded: 's1'};"> </span>ovvero<span style="{encoded: 's1'};"> </span>il Cammino più Corto o di Costo minimo (3)* * * concetto di rete bloccante, di rete non bloccante e di rete riarrangabile * la Benes * looping algorithm e instradamento sulla Benes *Il Problema del Layout di Topologie di Interconnessione ovvero il Disegno Ortogonale su Griglia (1)* * Il modello di Thompson * Il disegno ortogonale di grafi su griglia * Il layout della Butterfly * il layout di Wise %RED% *Lunedi' 15 Ottobre 2012 (Ore 7-8):* %ENDCOLOR% *Il Problema del Layout di Topologie di Interconnessione ovvero il Disegno Ortogonale su Griglia (2)* * Il layout della Butterfly (segue) * il layout di Even ed Even * panoramica di altri risultati * Layout della butterfly di area ottima %RED% *Mercoledi' 17 Ottobre 2012 (Ore 9-10):* %ENDCOLOR% *Il Problema del Layout di Topologie di Interconnessione ovvero il Disegno Ortogonale su Griglia (3)* * Il layout dell'ipercubo * il problema del layut 3D *Il Problema di infettare (e difendere) una rete con un Worm ovvero la Minima Copertura di Nodi (1)* * Il problema * i worm * danni causati dai worm * diffusione dei worm %RED% *Lunedi' 22 Ottobre 2012 (Ore 11-12):* %ENDCOLOR% *Il Problema di infettare (e difendere) una rete con un Worm ovvero la Minima Copertura di Nodi (2)* * Modello del problema su grafi * la minima copertura di nodi * definizione * un algoritmo 2-approssimante * insieme indipendente e sua relazione con la copertura di nodi * accoppiamento e sua relazione con la copertura di nodi * un ulteriore algoritmo approssimante * teorema di Konig-Egevary %RED% *Mercoledi' 24 Ottobre 2012 (Ore 13-14):* %ENDCOLOR% *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (1)* * Introduzione ai problemi di assegnazione di frequenze * Collisioni dirette, collisioni nascoste e grafo delle interferenze * L(h,k)-etichettatura e minima banda * Il caso speciale h=k in relazione al quadrato di un grafo %RED% *Lunedi' 29 Ottobre 2012 (Ore 15-16):* %ENDCOLOR% *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (2)* * L(h,k)-etichettatura (segue) * Dimostrazione delle proprietà della L(h,k)-etichettatura (h e k primi tra loro ed interi) * Dimostrazione della NP-completezza per grafi di diametro 2 * Limitazione inferiore di Delta+1 su lambbda * Esempio di grafo che richiede lambda=Delta quadro - Delta * Limitazione superiore di Delta quadro + 2 Delta * Congettura di Griggs e Yeh * Risultati esatti: clicche %RED% *Lunedi' 5 Novembre 2012 (Ore 17-18):* %ENDCOLOR% *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (3)* * L(h,k)-etichettatura (segue) * Risultati esatti: clicche * Risultati esatti: stelle * Risultati esatti: alberi * Risultati esatti: cammini * Risultati esatti: cicli %RED% *Mercoledi' 7 Novembre 2012 (Ore 19-20):* %ENDCOLOR% *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (4)* * L(h,k)-etichettatura (segue) * * Risultati approssimati: grafi outerplanar * varianti del problema: * L(2,1)-etichettatura orientata * L(h1, ..., hk)-etichettatura * backbone coloring * L(h,k)-etichettatura multipla * assegnazione di frequenze in reti GSM * una divagazione sul teorema dei 4 colori *Il Problema del Broadcast con minimo dispendio di energia ovvero il Minimo Albero Ricoprente (1)* * Il problema del MinBroadcast * NP-completezza e risultati di non approssimabilita' di MinBroadcast (riduzione da MinSetCover) %RED% *12-15 Novembre 2012: settimana di interruzione della didattica* %ENDCOLOR% %RED% *Lunedi' 19 Novembre 2012 (Ore 21-22):* %ENDCOLOR% *Il Problema del Broadcast con minimo dispendio di energia ovvero il Minimo Albero Ricoprente (2)* * Relazione tra MinBroadcast e MinSpanningTree * Il problema del Minimo Albero Ricoprente * Algoritmo di Kruskal * Algoritmo di Prim * Algoritmo di Boruvka * Il problema del Min Broadcast * Euristica MST * Euristica SPT * Euristica BAIP * fattore di approssimazione per SPT %RED% *Mercoledi' 21 Novembre 2012 (Ore 23-24):* %ENDCOLOR% *Il Problema del Dispiegamento centralizzato di Sensori Mobili ovvero il Minimo Accoppiamento Bipartito (1)* * Il problema del Dispiegamento centralizzato * Il problema modellato sui grafi: accoppiamento bipartito di peso minimo * Accoppiamento massimo in grafi bipartiti * teorema di P. Hall (dimostrazione) * corollario del th. di P. Hall (dim.) * equivalenza con il problema del minimo flusso * cammini aumentanti %RED% *Lunedi' 26 Novembre 2012 (Ore 25-26):* %ENDCOLOR% *Il Problema del Dispiegamento Centralizzato di Sensori Mobili ovvero il Minimo Accoppiamento Bipartito (2)* * Accoppiamento massimo in grafi bipartiti * teorema del cammino aumentante di Berge (dim.) * il problema della ricerca di un camino aumentante * algoritmo basato sul th. di Berge * l'algoritmo di Hopcroft e Karp * Accoppiamento perfetto di peso minimo in grafi bipartiti * cammini aumentanti * un algoritmo basato sui cammini aumentanti * formulazione del problema come programmazione lineare * Accoppiamento massimo in grafi qualunque * boccioli (blossoms) * lemma della contrazione dei cicli %RED% *Mercoledi' 28 Novembre 2012 (Ore 27-28):* %ENDCOLOR% *Il Problema del Dispiegamento Centralizzato di Sensori Mobili ovvero il Minimo Accoppiamento Bipartito (3)* * * algoritmo di Edmonds *Il Problema del Dispiegamento distribuito di Sensori Mobili ovvero la costruzione del Diagramma di Voronoi (2)* * Il problema * L'approccio basato sulle forze virtuali %RED% *Lunedi' 3 Dicembre 2012 (Ore 29-30):* %ENDCOLOR% *Il Problema del Dispiegamento distribuito di Sensori Mobili ovvero la costruzione del Diagramma di Voronoi (2)* * L'approccio basato sui diagrammi di Voronoi * Diagramma di Voronoi * posizione generale * proprieta' * Diagramma di Voronoi * complessita' * Il problema duale: la triangolazione di Delaunay * algoritmi per calcolare il diagramma di Voronoi: divide et impera * algoritmi per calcolare il diagramma di Voronoi: sweep line (algoritmo di Fortune) - prima parte %RED% *Mercoledi' 5 Dicembre 2012 (Ore 31-32):* %ENDCOLOR% *Il Problema del Dispiegamento distribuito di Sensori Mobili ovvero la costruzione del Diagramma di Voronoi (3)* * Diagramma di Voronoi * algoritmi per calcolare il diagramma di Voronoi: sweep line (algoritmo di Fortune) - seconda parte * Dispiegamento con sensori eterogenei * Distanza di Laguerre * Diagramma di Voronoi-Laguerre * L'approccio basato sui diagrammi di Voronoi-Laguerre * proprieta' dell'algoritmo ---+++ <font color="blue" size="+2">Diario delle Lezioni A.A. 2011-2012</font> %RED% *Lunedi' 3 Ottobre 2011 (Ore 1-2):* %ENDCOLOR% *Introduzione al Corso* *Il Problema dell'Instradamento<span style="{encoded: 's1'};"> </span>ovvero<span style="{encoded: 's1'};"> </span>il Cammino più Corto o di Costo minimo (1)* * Il problema dell'instradamento * Il problema del cammino di costo minimo * cammini piu' corti: visita in ampiezza %RED% *Giovedi' 6 Ottobre 2011 (Ore 3-4):* %ENDCOLOR% *Il Problema dell'Instradamento ovvero il Cammino più Corto o di Costo minimo (2)* * * cammini minimi: * algoritmo di Bellman-Ford * algoritmo di Dijkstra * algoritmo di Floyd-Warshall * Instradamento sulle Topologie di Interconnessione * il modello di packet switching * la Butterfly * instradamento sulla Butterfly %RED% *Lunedi' 10 Ottobre 2011 (Ore 5-6):* %ENDCOLOR% *Il Problema dell'Instradamento<span style="{encoded: 's1'};"> </span>ovvero<span style="{encoded: 's1'};"> </span>il Cammino più Corto o di Costo minimo (3)* * * concetto di rete bloccante, di rete non bloccante e di rete riarrangabile * la Benes * looping algorithm e instradamento sulla Benes *Il Problema del Layout di Topologie di Interconnessione ovvero il Disegno Ortogonale su Griglia (1)* * Il modello di Thompson * Il disegno ortogonale di grafi su griglia %RED% *Mercoledi' 12 Ottobre 2011 (Ore 7-8):* %ENDCOLOR% *Il Problema del Layout di Topologie di Interconnessione ovvero il Disegno Ortogonale su Griglia (2)* * Il layout della Butterfly * il layout di Wise * il layout di Even ed Even * panoramica di altri risultati %RED% *Lunedi' 17 Ottobre 2011 (Ore 9-10):* %ENDCOLOR% *Il Problema del Layout di Topologie di Interconnessione ovvero il Disegno Ortogonale su Griglia (3)* * Layout della butterfly di area ottima * Layout tridimensionale dell'ipercubo * il problema del layut 3D * l'ipercubo * cenni sul layout dell'ipercubo e sulla limitazione inferiore %RED% *Mercoledi' 19 Ottobre 2011 (Ore 11-12):* %ENDCOLOR% *Il Problema di infettare (e difendere) una rete con un Worm ovvero la Minima Copertura di Nodi* * Il problema * i worm * danni causati dai worm * diffusione dei worm * Modello del problema su grafi * la minima copertura di nodi * definizione * un algoritmo 2-approssimante * insieme indipendente e sua relazione con la copertura di nodi * accoppiamento e sua relazione con la copertura di nodi * un ulteriore algoritmo approssimante * teorema di Konig-Egevary %RED% *Lunedi' 24 Ottobre 2011 (Ore 13-14):* %ENDCOLOR% *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (1)* * Introduzione ai problemi di assegnazione di frequenze * Collisioni dirette, collisioni nascoste e grafo delle interferenze * L(h,k)-etichettatura e minima banda * Il caso speciale h=k in relazione al quadrato di un grafo * Dimostrazione delle proprietà della L(h,k)-etichettatura (h e k primi tra loro ed interi) %RED% *Mercoledi' 26 Ottobre 2011 (Ore 15-16):* %ENDCOLOR% *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (2)* * L(h,k)-etichettatura (segue) * Dimostrazione della NP-completezza per grafi di diametro 2 * Limitazione inferiore di Delta+1 su lambbda * Esempio di grafo che richiede lambda=Delta quadro - Delta * Limitazione superiore di Delta quadro + 2 Delta * Congettura di Griggs e Yeh * Risultati esatti: clicche * Risultati esatti: stelle * Risultati esatti: alberi %RED% *Mercoledi' 9 Novembre 2011 (Ore 17-18):* %ENDCOLOR% *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (3)* * L(h,k)-etichettatura (segue) * Risultati esatti: cammini * Risultati esatti: cicli * Risultati approssimati: grafi outerplanar %RED% *Lunedi' 21 Novembre 2011 (Ore 19-20):* %ENDCOLOR% *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (4)** varianti del problema: * * L(2,1)-etichettatura orientata * L(h1, ..., hk)-etichettatura * backbone coloring * L(h,k)-etichettatura multipla * assegnazione di frequenze in reti GSM * una divagazione sul teorema dei 4 colori *Il Problema del Broadcast con minimo dispendio di energia ovvero il Minimo Albero Ricoprente (1)* * Il problema del MinBroadcast * NP-completezza e risultati di non approssimabilita' di MinBroadcast (riduzione da MinSetCover) * Relazione tra MinBroadcast e MinSpanningTree %RED% *Mercoledi' 23 Novembre 2011 (Ore 21-22):* %ENDCOLOR% *Il Problema del Broadcast con minimo dispendio di energia ovvero il Minimo Albero Ricoprente (2)* * Il problema del Minimo Albero Ricoprente * Algoritmo di Kruskal * Algoritmo di Prim * Algoritmo di Boruvka * Il problema del Min Broadcast * Euristica MST * Euristica SPT * Euristica BAIP * fattore di approssimazione per SPT %RED% *Lunedi' 28 Novembre 2010 (Ore 23-24):* %ENDCOLOR% *Il Problema del Dispiegamento centralizzato di Sensori Mobili ovvero il Minimo Accoppiamento Bipartito (1)* * Il problema del Dispiegamento centralizzato * Il problema modellato sui grafi: accoppiamento bipartito di peso minimo * Accoppiamento massimo in grafi bipartiti * teorema di P. Hall (dimostrazione) * corollario del th. di P. Hall (dim.) * equivalenza con il problema del minimo flusso * cammini aumentanti * teorema del cammino aumentante di Berge (dim.) %RED% *Mercoledi' 30 Novembre 2010 (Ore 25-26):* %ENDCOLOR% *Il Problema del Dispiegamento centralizzato di Sensori Mobili ovvero il Minimo Accoppiamento Bipartito (2)* * Accoppiamento massimo in grafi bipartiti * il problema della ricerca di un camino aumentante * algoritmo basato sul th. di Berge * l'algoritmo di Hopcroft e Karp * Accoppiamento perfetto di peso minimo in grafi bipartiti * cammini aumentanti * un algoritmo basato sui cammini aumentanti * formulazione del problema come programmazione Lineare * Accoppiamento massimo in grafi qualunque * boccioli (blossoms) * lemma della contrazione dei cicli * algoritmo di Edmonds %RED% *Lunedi' 5 Dicembre 2011 (Ore 27-28):* %ENDCOLOR% *Il Problema del Dispiegamento distribuito di Sensori Mobili ovvero la costruzione del Diagramma di Voronoi (1)* * Il problema * L'approccio basato sulle forze virtuali * L'approccio basato sui diagrammi di Voronoi * Diagramma di Voronoi * posizione generale * proprieta' %RED% *Mercoledi' 7 Dicembre 2011 (Ore 29-30):* %ENDCOLOR% *Il Problema del Dispiegamento distribuito di Sensori Mobili ovvero la costruzione del Diagramma di Voronoi (2)* * Diagramma di Voronoi * complessita' * Il problema duale: la triangolazione di Delaunay * algoritmi per calcolare il diagramma di Voronoi: divide et impera * algoritmi per calcolare il diagramma di Voronoi: sweep line (algoritmo di Fortune) * Dispiegamento con sensori eterogenei * Distanza di Laguerre * Diagramma di Voronoi-Laguerre %RED% *Lunedi' 12 Dicembre 2011 (Ore 31-32):* %ENDCOLOR% *Il Problema del Dispiegamento distribuito di Sensori Mobili ovvero la costruzione del Diagramma di Voronoi (3)* * L'approccio basato sui diagrammi di Voronoi-Laguerre * proprieta' dell'algoritmo %BLUE% *Mercoledi' 14 Dicembre 2011 (Lauree)* %ENDCOLOR% %BLUE% *Vacanze natalizie* %ENDCOLOR% %RED% *Mercoledi' 11 Gennaio 2012 (Ore 33-34):* %ENDCOLOR% *Tesine* %RED% *Lunedi' 16 Gennaio 2012 (Ore 35-36):* %ENDCOLOR% *Tesine* %RED% *Mercoledi' 18 Gennaio 2012 (Ore 37-38):* %ENDCOLOR% *Tesine* --- ---+++ <font color="blue" size="+2">Diario delle Lezioni A.A. 2010-2011</font> %RED% *Lunedi' 18 Ottobre 2010 (Ore 1-2):* %ENDCOLOR% Lectio Magistralis: Dott. Prabhakar Raghavan %RED% *Giovedi' 21 Ottobre 2010 (Ore 3-4):* %ENDCOLOR% *Introduzione al Corso* *Il Problema dell'Instradamento ovvero il Cammino più Corto o di Costo minimo (1)* * Il problema dell'instradamento * Il problema del cammino di costo minimo * cammini piu' corti: visita in ampiezza * cammini minimi: * algoritmo di Bellman-Ford * algoritmo di Dijkstra * algoritmo di Floyd-Warshall %RED% *Lunedi' 25 Ottobre 2010 (Ore 5-6):* %ENDCOLOR% *Il Problema dell'Instradamento ovvero il Cammino più Corto o di Costo minimo (2)* * Instradamento sulle Topologie di Interconnessione * il modello di packet switching * la Butterfly * instradamento sulla Butterfly * concetto di rete bloccante, di rete non bloccante e di rete riarrangabile * la Benes * looping algorithm e instradamento sulla Benes %RED% *Giovedi' 28 Ottobre 2010 (Ore 7-8):* %ENDCOLOR% *Il Problema del Layout di Topologie di Interconnessione ovvero il Disegno Ortogonale su Griglia (1)* * Il modello di Thompson * Il disegno ortogonale di grafi su griglia * Il layout della Butterfly * il layout di Wise * il layout di Even ed Even * panoramica di altri risultati %BLUE% *Lunedi' 1 Novembre 2010:* festa %ENDCOLOR% %RED% *Giovedi' 4 Novembre 2010 (Ore 9-10):* %ENDCOLOR% *Il Problema del Layout di Topologie di Interconnessione ovvero il Disegno Ortogonale su Griglia (2)* * Layout della butterfly di area ottima * Layout tridimensionale dell'ipercubo * il problema del layut 3D * l'ipercubo * cenni sul layout e sulla limitazione inferiore *Il Problema di infettare (e difendere) una rete con un Worm ovvero la Minima Copertura di Vertici (1)* * Il problema * i worm * danni causati dai worm * diffusione dei worm %RED% *Lunedi' 8 Novembre 2010 (Ore 11-12):* %ENDCOLOR% *Il Problema di infettare (e difendere) una rete con un Worm ovvero la Minima Copertura di Nodi (2)* * Modello del problema su grafi * la minima copertura di nodi * definizione * un algoritmo 2-approssimante * insieme indipendente e sua relazione con la copertura di nodi * accoppiamento e sua relazione con la copertura di nodi * un ulteriore algoritmo approssimante * teorema di Konig-Egevary *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (1)* * Introduzione ai problemi di assegnazione di frequenze %RED% *Giovedi' 11 Novembre 2010 (Ore 13-14):* %ENDCOLOR% *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (2)* * Collisioni dirette, colisioni nascoste e grafo delle interferenze * L(h,k)-etichettatura e minima banda * Dimostrazione delle proprietà della L(h,k)-etichettatura (h e k primi tra loro ed interi) * Il caso speciale h=k * Dimostrazione della NP-completezza per grafi di diametro 2 * Limitazione inferiore di Delta+1 su lambbda * Esempio di grafo che richiede lambda=Delta quadro - Delta * Limitazione superiore di Delta quadro + 2 Delta %RED% *Lunedi' 15 Novembre 2010 (Ore 15-16):* %ENDCOLOR% *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (3)* * L(h,k)-etichettatura (segue) * Congettura di Griggs e Yeh * Risultati esatti: clicche * Risultati esatti: stelle * Risultati esatti: alberi * Risultati esatti: cammini * Risultati esatti: cicli * Risultati approssimati: grafi outerplanar %RED% *Giovedi' 18 Novembre 2010 (Ore 17-18):* %ENDCOLOR% *Un Problema di assegnazione di frequenze ovvero la L(h,k)-Etichettatura (4)** L(h,k)-etichettatura (segue) * * Risultati approssimati: grafi outerplanar * varianti del problema: * L(2,1)-etichettatura orientata * L(h1, ..., hk)-etichettatura * backbone coloring * assegnazione di frequenze in reti GSM * una divagazione sul teorema dei 4 colori %RED% *Lunedi' 22 Novembre 2010 (Ore 19-20):* %ENDCOLOR% *Il Problema del Broadcast con minimo dispendio di energia ovvero il Minimo Albero Ricoprente (1)* * Il problema del MinBroadcast * NP-completezza e risultati di non approssimabilita' di MinBroadcast (riduzione da MinSetCover) * Relazione tra MinBroadcast e MinSpanningTree * Il problema del Minimo Albero Ricoprente * Algoritmo di Kruskal * Algoritmo di Prim * Algoritmo di Boruvka * Il problema del Min Broadcast * Euristica MST * Euristica SPT * Euristica BAIP * fattore di approssimazione per SPT %RED% *Giovedi' 25 Novembre 2010 (Ore 21-22):* %ENDCOLOR% *Il Problema del Broadcast con minimo dispendio di energia ovvero il Minimo Albero Ricoprente (2)* * Il problema del Min Broadcast * fattore di approssimazione per BAIP * fattore di approssimazione per MST * idea della dimostrazione della lim. sup. di 6 per MST *Il Problema del Dispiegamento centralizzato di Sensori Mobili ovvero il Minimo Accoppiamento Bipartito (1)* * Il problema del Dispiegamento centralizzato * Il problema modellato sui grafi: accoppiamento bipartito di peso minimo * Accoppiamento massimo in grafi bipartiti * teorema di P. Hall (dimostrazione) * corollario del th. di P. Hall (dim.) * equivalenza con il problema del minimo flusso * cammini aumentanti * teorema del cammino aumentante di Berge (dim.) * il problema della ricerca di un camino aumentante * algoritmo basato sul th. di Berge * l'algoritmo di Hopcroft e Karp %BLUE% *Settimana di interruzione della didattica* %ENDCOLOR% %RED% *Lunedi' 6 Dicembre 2010 (Ore 23-24):* %ENDCOLOR% *Il Problema del Dispiegamento centralizzato di Sensori Mobili ovvero il Minimo Accoppiamento Bipartito (2)* * Accoppiamento perfetto di peso minimo in grafi bipartiti * cammini aumentanti * un algoritmo basato sui cammini aumentanti * formulazione del problema come programmazione Lineare * Accoppiamento massimo in grafi qualunque * boccioli (blossoms) * lemma della contrazione dei cicli * algoritmo di Edmonds *Il Problema del Dispiegamento distribuito di Sensori Mobili ovvero la costruzione del Diagramma di Voronoi (1)* * Il problema * L'approccio basato sulle forze virtuali * L'approccio basato sui diagrammi di Voronoi * Diagramma di Voronoi * posizione generale * proprieta' %RED% *Giovedi' 9 Dicembre 2010 (Ore 25-26):* %ENDCOLOR% *Il Problema del Dispiegamento distribuito di Sensori Mobili ovvero la costruzione del Diagramma di Voronoi (2)* * Diagramma di Voronoi * complessita' * Il problema duale: la triangolazione di Delaunay * algoritmi per calcolare il diagramma di Voronoi: divide et impera * algoritmi per calcolare il diagramma di Voronoi: sweep line (algoritmo di Fortune) %RED% *Lunedi' 13 Dicembre 2010 (Ore 27-28):* %ENDCOLOR% *Il Problema del Dispiegamento distribuito di Sensori Mobili ovvero la costruzione del Diagramma di Voronoi (3)* * Dispiegamento con sensori eterogenei * Distanza di Laguerre * Diagramma di Voronoi-Laguerre * L'approccio basato sui diagrammi di Voronoi-Laguerre * proprieta' dell'algoritmo %BLUE% *Giovedi' 16 Dicembre 2010 (Lauree)* %ENDCOLOR% %BLUE% *Lunedi' 20 Dicembre 2010 (Incontro con le aziende)* %ENDCOLOR% %BLUE% *Vacanze natalizie* %ENDCOLOR% %RED% *Lunedi' 10 Gennaio 2011 (Ore 29-30):* %ENDCOLOR% *Tesine* %RED% *Giovedi' 13 Gennaio 2011 (Ore 31-32):* %ENDCOLOR% *Tesine* %RED% *Venerdi' 14 Gennaio 2011 (Ore 33-34):* %ENDCOLOR% *Tesine* %RED% *Lunedi' 17 Gennaio 2011 (Ore 35-36):* %ENDCOLOR% *Tesine* %RED% *Giovedi' 20 Gennaio 2011 (Ore 37-38):* %ENDCOLOR% *Tesine* -- %USERSIG{TizianaCalamoneri - 2021-09-23}% ---++ Comments %COMMENT%
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