Three-dimensional(3-D)Markov cubic random mesh models are presented andproved in the form of two theorems in details.Its applications to the modeling and description of3-D images are described.The model presented here...Three-dimensional(3-D)Markov cubic random mesh models are presented andproved in the form of two theorems in details.Its applications to the modeling and description of3-D images are described.The model presented here is a appropriate mathematical tool for thesegmentation,modeling,classification and other processing.Finally,an example is given.展开更多
The probability model is used to analyze the fault tolerance of mesh. To simplify its analysis, it is as-sumed that the failure probability of each node is independent. A 3-D mesh is partitioned into smaller submeshes...The probability model is used to analyze the fault tolerance of mesh. To simplify its analysis, it is as-sumed that the failure probability of each node is independent. A 3-D mesh is partitioned into smaller submeshes,and then the probability with which each submesh satisfies the defined condition is computed. If each submesh satis-fies the condition, then the whole mesh is connected. Consequently, the probability that a 3-D mesh is connected iscomputed assuming each node has a failure probability. Mathematical methods are used to derive a relationship be-tween network node failure probability and network connectivity probability. The calculated results show that the 3-D mesh networks can remain connected with very high probability in practice. It is formally proved that when thenetwork node failure probability is boutded by 0.45 %, the 3-D mesh networks of more than three hundred thousandnodes remain connected with probability larger than 99 %. The theoretical results show that the method is a power-ful technique to calculate the lower bound of the connectivity probability of mesh networks.展开更多
In this paper, the concept of k-submesh and k-submesh connectivity fault tolerance model is proposed. And the fault tolerance of 3-D mesh networks is studied under a more realistic model in which each network node has...In this paper, the concept of k-submesh and k-submesh connectivity fault tolerance model is proposed. And the fault tolerance of 3-D mesh networks is studied under a more realistic model in which each network node has an independent failure probability. It is first observed that if the node failure probability is fixed, then the connectivity probability of 3-D mesh networks can be arbitrarily small when the network size is sufficiently large. Thus, it is practically important for multicomputer system manufacturer to determine the upper bound for node failure probability when the probability of network connectivity and the network size are given. A novel technique is developed to formally derive lower bounds on the connectivity probability for 3-D mesh networks. The study shows that 3-D mesh networks of practical size can tolerate a large number of faulty nodes thus are reliable enough for multicomputer systems. A number of advantages of 3-D mesh networks over other popular network topologies are given. Compared to 2-D mesh networks, 3-D mesh networks are much stronger in tolerating faulty nodes, while for practical network size, the fault tolerance of 3-D mesh networks is comparable with that of hypercube networks but enjoys much lower node degree.展开更多
Broadcast is one of the most important approach in distributed memory parallel computers that is used to find a routing approach from one source to all nodes in the mesh. Broadcasting is a data communication task in w...Broadcast is one of the most important approach in distributed memory parallel computers that is used to find a routing approach from one source to all nodes in the mesh. Broadcasting is a data communication task in which corresponds to one-to-all communication. Routing schema is the approach used to determine the road that is used to send a message from a source node to destination nodes. In this paper, we propose an efficient algorithm for broadcasting on an all-port wormhole-routed 3D mesh with arbitrary size. Wormhole routing is a fundamental routing mechanism in modern parallel computers which is characterized with low communication latency. We show how to apply this approach to 3-D meshes. In wormhole, routing large network packets are broken into small pieces called FLITs (flow control digits). The destination address is kept in the first flit which is called the header flit and sets up the routing behavior for all subsequent flits associated with the packet. In this paper, we introduce an efficient algorithm, X-Hamiltonian Surface Broadcast (X-HSB) which uses broadcast communication facility with deadlock-free wormhole routing in general three dimensional networks. In this paper, the behaviors of this algorithm are compared to the previous results using simulation;our paradigm reduces broadcast latency and is simpler. The results presented in this paper indicate the advantage of our proposed algorithm.展开更多
Wave breaking plays an important role in wave-structure interaction. A novel control volume finite element method with adaptive unstructured meshes is employed here to study 3-D breaking waves. The numerical framework...Wave breaking plays an important role in wave-structure interaction. A novel control volume finite element method with adaptive unstructured meshes is employed here to study 3-D breaking waves. The numerical framework consists of a "volume of fluid" type method for the interface capturing and adaptive unstructured meshes to improve computational efficiency. The numerical model is validated against experimental measurements of breaking wave over a sloping beach and is then used to study the breaking wave impact on a vertical circular cylinder on a slope. Detailed complex interfacial structures during wave impact, such as plunging jet formation and splash-up are captured in the simulation, demonstrating the capability of the present method.展开更多
文摘Three-dimensional(3-D)Markov cubic random mesh models are presented andproved in the form of two theorems in details.Its applications to the modeling and description of3-D images are described.The model presented here is a appropriate mathematical tool for thesegmentation,modeling,classification and other processing.Finally,an example is given.
基金Project (69928201) supported by the National Science Fund for Distinguished Young Scholars+1 种基金project (90104028) by the National Natural Science Foundation of China Project by Changjiang Scholar Re-ward Project
文摘The probability model is used to analyze the fault tolerance of mesh. To simplify its analysis, it is as-sumed that the failure probability of each node is independent. A 3-D mesh is partitioned into smaller submeshes,and then the probability with which each submesh satisfies the defined condition is computed. If each submesh satis-fies the condition, then the whole mesh is connected. Consequently, the probability that a 3-D mesh is connected iscomputed assuming each node has a failure probability. Mathematical methods are used to derive a relationship be-tween network node failure probability and network connectivity probability. The calculated results show that the 3-D mesh networks can remain connected with very high probability in practice. It is formally proved that when thenetwork node failure probability is boutded by 0.45 %, the 3-D mesh networks of more than three hundred thousandnodes remain connected with probability larger than 99 %. The theoretical results show that the method is a power-ful technique to calculate the lower bound of the connectivity probability of mesh networks.
文摘In this paper, the concept of k-submesh and k-submesh connectivity fault tolerance model is proposed. And the fault tolerance of 3-D mesh networks is studied under a more realistic model in which each network node has an independent failure probability. It is first observed that if the node failure probability is fixed, then the connectivity probability of 3-D mesh networks can be arbitrarily small when the network size is sufficiently large. Thus, it is practically important for multicomputer system manufacturer to determine the upper bound for node failure probability when the probability of network connectivity and the network size are given. A novel technique is developed to formally derive lower bounds on the connectivity probability for 3-D mesh networks. The study shows that 3-D mesh networks of practical size can tolerate a large number of faulty nodes thus are reliable enough for multicomputer systems. A number of advantages of 3-D mesh networks over other popular network topologies are given. Compared to 2-D mesh networks, 3-D mesh networks are much stronger in tolerating faulty nodes, while for practical network size, the fault tolerance of 3-D mesh networks is comparable with that of hypercube networks but enjoys much lower node degree.
文摘Broadcast is one of the most important approach in distributed memory parallel computers that is used to find a routing approach from one source to all nodes in the mesh. Broadcasting is a data communication task in which corresponds to one-to-all communication. Routing schema is the approach used to determine the road that is used to send a message from a source node to destination nodes. In this paper, we propose an efficient algorithm for broadcasting on an all-port wormhole-routed 3D mesh with arbitrary size. Wormhole routing is a fundamental routing mechanism in modern parallel computers which is characterized with low communication latency. We show how to apply this approach to 3-D meshes. In wormhole, routing large network packets are broken into small pieces called FLITs (flow control digits). The destination address is kept in the first flit which is called the header flit and sets up the routing behavior for all subsequent flits associated with the packet. In this paper, we introduce an efficient algorithm, X-Hamiltonian Surface Broadcast (X-HSB) which uses broadcast communication facility with deadlock-free wormhole routing in general three dimensional networks. In this paper, the behaviors of this algorithm are compared to the previous results using simulation;our paradigm reduces broadcast latency and is simpler. The results presented in this paper indicate the advantage of our proposed algorithm.
基金the financial support by the National Natural Science Foundation of China (Grant No. 51490673)the Open Awards of the State Key Laboratory of Coastal and Offshore Engineering+1 种基金funded by the EPSRC MEMPHIS multiphase Programme (Grant No. EP/K003976/1)funding from the European Union Seventh Framework Programme (FP7/20072013) under grant agreement No. 603663 for the research project PEARL (Preparing for Extreme and Rare events in coasta L regions)
文摘Wave breaking plays an important role in wave-structure interaction. A novel control volume finite element method with adaptive unstructured meshes is employed here to study 3-D breaking waves. The numerical framework consists of a "volume of fluid" type method for the interface capturing and adaptive unstructured meshes to improve computational efficiency. The numerical model is validated against experimental measurements of breaking wave over a sloping beach and is then used to study the breaking wave impact on a vertical circular cylinder on a slope. Detailed complex interfacial structures during wave impact, such as plunging jet formation and splash-up are captured in the simulation, demonstrating the capability of the present method.