30471911
Hamiltonian Decompositions of Cayley Graphs on Abelian Groups of Odd Order
33569862
Survey of Double Vertex Graphs
Abstract. Let G be a (V,E) graph of order p≥2. The double vertex graphU2(G) is the graph whose vertex set consists of all 2-subsets of V such that two distinct vertices {x,y} and {u,v} are adjacent if and only if |{x,y}∩{u,v}|=1 and if x=u, then y and v are adjacent in G. For this class of graphs we discuss the regularity, eulerian, hamiltonian, and bipartite properties of these graphs. A generalization of this concept is n-tuple vertex graphs, defined in a manner similar to double vertex graphs. We also review several recent results for n-tuple vertex graphs.
6396851
Multiagent diffusion and distributed optimization
Distributed problem solving by a multiagent system represents a promising approach to solving complex computational problems. However, many multiagent systems require certain degree of planning, coordination and negotiation to achieve the given goal. This paper presents a multiagent framework for tackling global optimization tasks inspired by diffusion in nature. The framework is designed for situations where agent communication must be kept to a minimal. Hence, complicated coordination and negotiation is not possible. Distributed agents in this framework share the common goal of finding the global optimal solution. They cooperate to achieve this common goal by sharing and updating a common belief that captures their estimation of the whereabouts of the optimal solution. To facilitate this, agents are naturally organized in families with a parent and its offsprings as members. This paper also presents an algorithm called Evolutionary Diffusion Optimization, which is implemented base on the proposed agent framework. Experimental results on some benchmark problems are presented together with performance comparison with a simulated annealing algorithm.
10618110
Dominating subgraphs in graphs with some forbidden structures
Abstract We characterize the triangle-free graphs with neither induced path of six vertices nor induced cycle of six vertices and the triangle-free graphs without induced path of six vertices in terms of dominating subgraphs.
215341
Experimental results on user knowledge assessment with an evidential reasoning methodology
User modeling is a crucial element of intelligent interfaces. This paper presents some preliminary resultson a method for the assessment of user knowledge. Knowledge of an individual is modeled as a subset of a global set of knowledge units (KU). The KUS are interrelated among each other through implication relations, indicating that certain KUS are prerequisite to others. The structure of implications is induced algorithmically through an induction procedure utilizing empirical data on the knowledge state of a number of subjects. It is thereafter used in a knowledge assessment process based on the Dempster-Shafer evidential reasoning methodology. The preliminary results demonstrate that our approach can successfully assess knowledge by randomly sampling KUS in a knowledge state and infer which KUS are known and unknown.
8844798
Learning not to share
Strong reasons exist for executing a large-scale discrete-event simulation on a cluster of processor nodes (each of which may be a shared-memory multiprocessor or a uniprocessor). This is the architecture of the largest scale parallel machines, and so the largest simulation problems can only be solved this way. It is a common architecture even in less esoteric settings, and is suitable for memory-bound simulations. This paper describes our approach to porting the SSF simulation kernel to this architecture, using the Message Passing Interface (MPI) system. The notable feature of this transformation is to support an efficient two-level synchronization and communication scheme that addresses cost discrepancies between shared-memory and distributed memory. In the initial implementation, we use a globally synchronous approach between distributed-memory nodes, and an asynchronous shared-memory approach within a SMP cluster. The SSF API reflects inherently shared-memory assumptions; we report therefore on our approach for porting an SSF kernel to a cluster of SMP nodes. Experimental results on two architectures are described, for a model of TCP/IP traffic flows over a hierarchical network. The performance on a distributed network of commodity SMPs connected through ethernet is seen to frequently exceed performance on a Sun shared-memory multiprocessor.
35455221
A characterization of pancyclic complements of line graphs
Abstract We characterize graphs G such that the complements of their line graphs are pancyclic.