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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

Secure coverage-preserving node scheduling scheme using energy prediction for wireless sensor networks

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The Journal of china Universities of Posts and Telecommunications 2010年第5期17卷 100-108页

作者： LI Zhi-yuan,WANG Ru-chuan. College of computer,nanjing university of Posts and Telecommunications,nanjing 210003,china College of computer Nanjing University of Posts and Telecommunications Nanjing 210003 China

With the fast development of the micro-electro-mechanical systems （MEMS）,wireless sensor networks （WSNs） have been extensively *** of the studies focus on saving energy consumption because of restricted energy supply in ***-based node scheduling scheme is commonly considered as one of the most energy-efficient ***,it is not always so efficient especially when there exist hot spot and network attacks in *** this article,a secure coverage-preserved node scheduling scheme for WSNs based on energy prediction is proposed in an uneven deployment *** scheme is comprised of an uneven clustering algorithm based on arithmetic progression,a cover set partition algorithm based on trust and a node scheduling algorithm based on energy *** results show that network lifetime of the scheme is 350 rounds longer than that of other scheduling ***,the scheme can keep a high network coverage ratio during the network lifetime and achieve the designed objective which makes energy dissipation of most nodes in WSNs balanced.

关键词： wireless sensor networks secure energy-efficient coverage node scheduling cover set energy prediction

An Exact Virtual Network Embedding Algorithm Based on Integer Linear Programming for Virtual Network Request with Location Constraint

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china Communications 2016年第8期13卷 177-183页

作者： Zeheng Yang Yongan Guo school of computer science and Engineering University of Electronic Science and Technology of China(UESTC) College of Telecommunications and Information Engineering Nanjing University of Posts and Telecommunications

Network virtualization is known as a promising technology to tackle the ossification of current Internet and will play an important role in the future network area. Virtual network embedding(VNE) is a key issue in network virtualization. VNE is NP-hard and former VNE algorithms are mostly heuristic in the *** exact algorithms have been developed in recent years. However, the constraints of exact VNE are only node capacity and link *** on these, this paper presents an exact VNE algorithm, ILP-LC, which is based on Integer Linear Programming(ILP), for embedding virtual network request with location constraints. This novel algorithm is aiming at mapping virtual network request(VNR) successfully as many as possible and consuming less substrate *** topology of each VNR is randomly generated by Waxman model. Simulation results show that the proposed ILP-LC algorithm outperforms the typical heuristic algorithms in terms of the VNR acceptance ratio, at least 15%.

关键词： network virtualization virtual network embedding exact VNE algorithm integer linear Programming location constraint VNR acceptance ratio

Alkali-silica Reactivity of Different Aggregates from Mineral and Textural Characteristics

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Journal of Wuhan university of technology(Materials science) 2008年第6期23卷 901-906页

作者：莫祥银 Analysis and Testing Center & Jiangsu Key Laboratory of Biofunctional Materials Nanjing Normal University

To identify the aggregates causing the alkali-silica reaction, and the reactivity of rocks in different parts of china, the mineral and texture characteristics of some typical coarse ag gregates and the alkali reactivity of these aggregates were systematically investigated. On one hand, petrographic examination of aggregates, combined with X-ray diffraction analysis, chemical analysis, scanning electron microscopy, was conducted for analyzing their mineralogy and texture. It was found that not only mineral characteristics, but also their interior structure would affect their potential alkali-silica reactivity. Furthermore, the alkali-silica reactivity of aggregates is due to their mineral compositions, such as containing different alkali-reactive minerals, while, different stuctures of those aggregates with similar minerals affect their reactivity to some extent. There are some amount of micro-aperture and cracks across the quartz in the aggregate, which may become the natural accesses for Na^＋, K^＋, and OH^- ions to intrude in the mortar or concrete during the process of alkali-silica reaction. Alkali-silica reactivity of the aggregates was detected by the accelerated mortar bars test. It was revealed that all the aggregates tested were alkali-silica reactive and the results were also in accordance with their mineral and structure analysis.

关键词： petrographic examination of aggregates study of thin sections x-ray diffraction analysis chemical analysis scanning electron microscopy

The Report of Virtual Exhibition Software Development

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Wuhan university Journal of Natural sciences 2001年第Z1期6卷 340-346页

作者： Yu Jian xin 1, Sun Yuan hao 1, Gong Zhen yu 2, Cao Jing 2 1. State Key Laboratory for Novel Software technology, nanjing university, nanjing 210093, china 2. Department of computer science and technology, nanjing university,nanjing 210093, china State Key Laboratory for Novel Software technology Nanjing University Nanjing China Department of computer science and technology Nanjing University Nanjing China

The main structure and key techniques of our Virtual Exhibition Software are summarized. It demonstrates the practice of Software Engineering during the development of our project and discusses the use of UML in it.

关键词： software engineering software process software quality assurance software configuration management software configuration item UML virtual reality

Power allocation scheme for selfish cooperative communications based on game theory and particle swarm optimizer

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science china(Information sciences) 2010年第9期53卷 1908-1912页

作者： ZHANG GuoPeng1*,YANG Kun2 & DING EnJie3 1school of computer science and technology,china university of Mining and technology,Xuzhou 221116,china 2school of computer science and Electronic Engineering,university of Essex Wivenhoe Park,Colchester CO_4 3SQ,UK 3school of Information and Electrical Engineering,china university of Mining and technology,Xuzhou 221116,china school of computer science and technology China University of Mining and Technology Xuzhou China school of computer science and Electronic Engineering University of Essex Wivenhoe Park Colchester UK school of Information and Electrical Engineering China University of Mining and Technology Xuzhou China

In commercial networks,autonomous user nodes operating on batteries are assumed to be selfish to consume their energy solely to maximize their own benefits,e.g.,data *** this letter a two-user cooperative game is proposed to perform the power allocation for selfish cooperative communication *** the game,one selfish user node could trade its transmission power for the other ones cooperative relaying directly,and both user nodes are willing to achieve an optimal data-rate increase through cooperative *** find the Nash bargaining solution(NBS) of the game,a low-complexity numerical particle swarm optimizer(PSO) algorithm is also *** results indicate that the NBS of the game is efficient,in that both users could experience better performance than they work independently,and fair,in that the degree of cooperation of a user node only depends on how much contribution its partner can make to improve its own performance.

关键词： cooperative communication power allocation game theory Nash bargaining solution particle swarm optimizer

Adaptive bidirectional diffusion for image restoration

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science china(Information sciences) 2010年第12期53卷 2452-2460页

作者： FU ShuJun 1,2 & ZHANG CaiMing 1 1 school of computer science and technology, Shandong university, Jinan 250101, china 2 school of Mathematics, Shandong university, Jinan 250100, china school of computer science and technology Shandong University Jinan China school of Mathematics Shandong University Jinan China

A large number of applications in image processing and computer vision depend on image quality. In this paper, combining the forward diffusion with the backward diffusion by different weights, we present an adaptive bidirectional diffusion method for image denoising and deblurring simultaneously. Further, we introduce a gradient factor into the data fidelity term, which forms a spatially varying constraint and allows a better restoration of image edges and fine details. In order to obtain a stable solution, we develop a numerically stable scheme and give its theoretical analysis. Finally, we show advantages of this method in deblurring edges, denoising and restoring fine details of image compared with other related methods in experiments.

关键词： image restoration bidirectional diffusion inverse diffusion anisotropic diffusion stabilizing scheme spatially varying constraint

Key technologies of new malicious code developments and defensive measures in communication networks

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The Journal of china Universities of Posts and Telecommunications 2010年第4期17卷 69-73页

作者： LI Peng,WANG Ru-chuan ,ZHANG Wei College of computer,nanjing university of Posts and Telecommunications,nanjing 210003,china College of computer Nanjing University of Posts and Telecommunications Nanjing 210003 China

This article is focused on analyzing the key technologies of new malicious code and corresponding defensive measures in the large-scale communication networks. Based on description of the concepts and development of the malicious code, the article introduces the anti-analysis technology, splitting and inserting technology, hiding technology, polymorph virus technology, and auto production technology of the malicious code trends with intelligence, diversity and integration. Following that, it summarizes the security vulnerabilities of communication networks from four related layers aspects, according to the mechanisms of malicious code in the communication networks. Finally, it proposes rapid response disposition of malicious code attacks from four correlated steps： building up the network node monitoring system, suspicious code feature automation analysis and extraction, rapid active malicious code response technique for unknown malicious code, and malicious code attack immunity technique. As a result, it actively defenses against the unknown malicious code attacks and enhances the security performance of communication networks.

关键词： network security malicious code network attack and defense malicious code defense

Theorems for Testing Local Activity of CNN and Application to Cardiac Purkinje Equations

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 139-146页

作者： Lequan Min(Applied science school, university of science and technology Beijing, Beijing 100083, china) Applied science school University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the local in one-port cellular neural/inear network (CNN) cells with four local state variables are presented. Using the theorems computes the bifurcation diagrams of the cardiac Purkinje fiber (CPE) equations Which describethe long-lasting action and pace-maker potentials of the Purkinje fiber of the heart. The computer simulation shows that periodic trajectories or convergent trajectories of the CPF Equations can be foun if the cormsponing cell Parameters are located in a positive domainbut nearby edge of chaos. In particular a heart with approximate normal frequency of heartbeat but non-normal electrocardiogram maysuddenly stop by slightly perturbing the parameters of the corresponding CPF Equations when the Paramders are located nearby the edge of chaos in the bifurcation diagrams. This research seems to interpret reasonbly the phenomena that patients with cardiac diseases might suddenly die without warning.

关键词： cellular neural network local activity cardiac Purkinje fiber heartbeat