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Advances in Manufacturing 1998年第2期2卷 60-63页

作者： Liu Yongcai (school of computer Engineering and science) school of computer Engineering and science Shanghai University Shanghai

Bushnell and the author proposed the neural networks for NOT, AND, OR, NAND, NOR, XOR and XNOR gates. Using these neural networks, the neural networks of any logic circuits can be constructd. From this, the consistent signals in the logic circuits will be transformed into the global minimal points of a quadratic pseudo Boolean function. Thus the neural network application in the field of circuit modeling and automatic test pattern generation can be widened.

关键词： neural network Hopfield network quadratic pseudo Boolean function k tree

A 14/11-approximation algorithm for sorting by short block-moves

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science China(Information sciences) 2011年第2期54卷 279-292页

作者： JIANG HaiTao & ZHU DaMing school of computer science and Technology, Shandong University, Jinan 250101, China school of computer science and Technology Shandong University Jinan China

Block-move is one of the popular operations for genome rearrangement. A short block-move is an operation on a permutation that moves an element at most two positions away from its original position. Heath and Vergara investigated the problem of finding a minimum-length sorting sequence of short block-moves for a given permutation and devised a 4/3-approximation algorithm. In this paper, we present a new 14/11-approximation algorithm for this problem. Firstly, we devise an exact polynomial time algorithm for sorting a special kind of sub permutations called umbrella; then we split the permutation into a series of related umbrellas and sort them greedily. We obtain a new lower bound of the short block-move distance by exploiting the properties of five kinds of sub-permutations. After some complicated analysis, we prove that the approximation ratio of the new algorithm is at most 14/11.

关键词： short block-move approximation algorithm

An efficient and DoS-resistant user authentication scheme for two-tiered wireless sensor networks

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Journal of Zhejiang University-science C(computers and Electronics) 2011年第7期12卷 550-560页

作者： Rong FAN ,Dao-jing HE ,Xue-zeng PAN,Ling-di PING (school of computer science and Technology,Zhejiang University,Hangzhou 310027,China) school of computer science and Technology Zhejiang University Hangzhou China

Wireless sensor networks (WSNs) are vulnerable to security attacks due to their deployment and resource *** that most large-scale WSNs follow a two-tiered architecture,we propose an efficient and denial-of-service (DoS)-resistant user authentication scheme for two-tiered *** proposed approach reduces the computational load,since it performs only simple operations,such as exclusive-OR and a one-way hash *** feature is more suitable for the resource-limited sensor nodes and mobile *** it is unnecessary for master nodes to forward login request messages to the base station,or maintain a long user *** addition,pseudonym identity is introduced to preserve user *** clever design,our proposed scheme can prevent smart card ***,security and performance analysis demonstrates the effectiveness and robustness of the proposed scheme.

关键词： User authentication User anonymity Smart card Two-tiered Wireless sensor network (WSN)

Quasi-physical global optimization method for solving the equal circle packing problem

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science China(Information sciences) 2011年第7期54卷 1333-1339页

作者： HUANG WenQi & YE Tao school of computer science and Technology,Huazhong University of science and Technology,Wuhan 430074,China school of computer science and Technology Huazhong University of Science and Technology Wuhan China

The equal circle packing problem is a well-known challenge in *** is also a natural,clear and fair test system for global *** paper presents a quasi-physical global optimization algorithm for solving the equal circle packing *** algorithm simulates two kinds of movements of N elastic disks: smooth movement driven by elastic pressures and violent movement driven by strong repulsive forces and attractive *** smooth movement makes the disks reach a locally optimal configuration,while the violent movement makes them jump out of the local optimum trap and reach a more promising *** algorithm is tested on the widely studied instances of N = 1,2,...,*** find better packings than the reported best-known ones on 37 instances and reproduce the best-known results on the remaining 113 instances.

关键词： equal circle packing global optimization quasi-physical method heuristic

A quasi-human algorithm for solving the three-dimensional rectangular packing problem

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science China(Information sciences) 2010年第12期53卷 2389-2398页

作者： HE Kun & HUANG WenQi school of computer science and Technology, Huazhong University of science and Technology, Wuhan 430074, China school of computer science and Technology Huazhong University of Science and Technology Wuhan China

Based on the concept of maximal rectangular space that can be filled at current time and the siege warfare tactics, we make several critical improvements on the quasi-human caving-degree approach to get a stronger algorithm ICDA for a classical NP hard problem: the three-dimensional rectangular packing problem. Within similar computing time, the new algorithm gained an average volume utilization of 90.92% on the natural and difficult 100 benchmarks, called BR15, where items to be packed are almost different in size. Compared with current best record just reported in the literature in 2010, our result makes an improvement by 0.54%.

关键词： NP hard three-dimensional packing quasi-human action space caving degree

Image stylization with enhanced structure on GPU

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science China(Information sciences) 2012年第5期55卷 1093-1105页

作者： LI Ping 1,SUN HanQiu 1,SHENG Bin 1,2 & SHEN JianBing 3 1 Department of computer science and Engineering,The Chinese University of Hong Kong,Hong Kong,China 2 Department of computer science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China 3 school of computer science and Technology,Beijing Institute of Technology,Beijing 100081,China Department of computer science and Engineering The Chinese University of Hong Kong Hong Kong China Department of computer science and Engineering Shanghai Jiao Tong University Shanghai China school of computer science and Technology Beijing Institute of Technology Beijing China

This paper presents a graphics processing unit (GPU) based stylization approach that preserves the fine structure between the original and the stylized images using gradient *** abstraction and painterly stylization methods focused on contrast manipulation only,and thus the detailed salient structures of the input images are always destroyed when performing the current stylization techniques because of limitations like unavoidable salience information loss caused by contrast *** propose an image structure map to naturally model the fine structure existing in the original ***-based structure tangent generation and tangent-guided image morphology are used to construct the structure *** image structure map,unlike an edge map,not only systematically models the boundary information within the imagery but also accentuates the underlying inner structure detail for further *** facilitate the final stylization via parallel bilateral grid and structure-aware stylizing optimization on a GPU-CUDA platform in real *** multiple experiments,the proposed method consistently demonstrates efficient and high quality image stylization performance.

关键词： image stylization non-photorealistic rendering real-time processing GPU image abstraction

Characterizations of α-Bloch functions on the unit ball without use of derivative

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science China Mathematics 2008年第11期51卷 1965-1981页

作者： CHEN HuaiHui school of Mathematics and computer science, Nanjing Normal University, Nanjing 210097, China school of Mathematics and computer science Nanjing Normal University Nanjing China

In this paper we establish characterizations of α-Bloch functions on the unit ball without use of derivative, which are stronger, more precise and general than those obtained by Nowak and Zhao.

关键词： α-Bloch function unit ball Bergman metric 32A18 32A37

Minimal regular 2-graphs and applications

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science China Mathematics 2006年第2期49卷 158-172页

作者： FAN Hongbing, LIU Guizhen & LIU Jiping Department of Physics and computer science, Wilfrid Laurier University, Waterloo, ON., N2L 3C5 Canada school of Mathematics and System science, Shandong University, Jinan 250100, China Department of Mathematics and computer science, University of Lethbridge, Lethbridge, AB., T1K 3M4, Canada Department of Physics and computer science Wilfrid Laurier University Waterloo Canada school of Mathematics and System science Shandong University Jinan China Department of Mathematics and computer science University of Lethbridge Lethbridge Canada

A 2-graph is a hypergraph with edge sizes of at most two. A regular 2-graph is said to be minimal if it does not contain a proper regular factor. Let f2(n) be the maximum value of degrees over all minimal regular 2-graphs of n vertices. In this paper, we provide a structure property of minimal regular 2-graphs, and consequently, prove that f2(n) = n+3-i/3, where 1 ≤ i ≤ 6, i ≡ n (mod 6) and n ≥ 7, which solves a conjecture posed by Fan, Liu, Wu and Wong. As applications in graph theory, we are able to characterize unfactorable regular graphs and provide the best possible factor existence theorem on degree conditions. Moreover, fa(n) and the minimal 2-graphs can be used in the universal switch box designs, which originally motivated this study.

关键词： graph regular factor 2-graph switch box design.

Service Composition Instantiation Based on Cross-Modified Artificial Bee Colony Algorithm

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China Communications 2016年第10期13卷 233-244页

作者： Lei Huo Zhiliang Wang school of Automation University of Science and Technology Beijing school of computer and science University of Science and Technology Beijing

Internet of things(IoT) imposes new challenges on service composition as it is difficult to manage a quick instantiation of a complex services from a growing number of dynamic candidate services. A cross-modified Artificial Bee Colony Algorithm(CMABC) is proposed to achieve the optimal solution services in an acceptable time and high accuracy. Firstly, web service instantiation model was established. What is more, to overcome the problem of discrete and chaotic solution space, the global optimal solution was used to accelerate convergence rate by imitating the cross operation of Genetic algorithm(GA). The simulation experiment result shows that CMABC exhibited faster convergence speed and better convergence accuracy than some other intelligent optimization algorithms.

关键词： optimization of service composition optimal service instantiation artificial bee colony algorithm swarm algorithm cross strategy