摘要：
This paper analyses structure and algorithm of Floating-Point ALU, and implements multiplication and division operation in the homo-hardware circuit. The Floating-Point multiplication and division ALU supports Floating-Point number according with IEEE-754 standard. This ALU adopts 4-Level pipelining structure: '0' operation number check, exponent addition and subtraction operation, fraction multiplication and division operation, result normalization and round. Each step can act as a single module. Among these modules, there are some registers which can prepare necessary data for next operation.
会议名称：
First IITA International Joint Conference on Artificial Intelligence, Hainan Island, China, 25-26 April 2009
关键词：
MIPS;Data Flow;Data Path;Pipeline
摘要：
In this paper, we analyze MIPS instruction format-, instruction data path-, decoder module function and design theory basend on RISC CPUT instruction set. Furthermore, we design instruction fetch (ZF) module of 32-bit CPU based on RISC CPU instruction set. Function of IF module mainly includes fetch instruction and latch module -, address arithmetic module-, check validity of instruction module-, synchronous control module. Function of IF modules are implemented by pipeline and simulated successfully on Quartus ll.
摘要：
The DoS attack is the most popular attack in the network security with the development of network and internet. In this paper, the DoS attack principle is discussed and some DoS attack methods are deeply analyzed. The DoS attack detection technologies which include network traffic detection and packet content detection are presented. The DDoS based on DoS is introduced and some DDoS tools are described and the important TCP flood DoS attack theory is discussed. The DoS attack program and a DoS attack detection program based on Winpcap for experiment are designed and the network packet generation and capture are implemented. The experiment expressed the key progress of DoS attack and detection in detail.
作者机构：
[Zhou Kang; Tong Xiaojun] Wuhan Polytech Univ, Dept Math & Phys, Wuhan 430023, Peoples R China.;[Zhou Kang; Tong Xiaojun; Xu Jin] Huazhong Univ Sci & Technol, Dept Control Sci & Engineer, Wuhan 430074, Peoples R China.
通讯机构：
[Zhou Kang] W;Wuhan Polytech Univ, Dept Math & Phys, Wuhan 430023, Peoples R China.
关键词：
closed circle DNA computing model;change positive-weighted Hamilton circuit problem;group insert experiment;group delete experiment
摘要：
Chain length of closed circle DNA is equal. The same closed circle DNA's position corresponds to different recognition sequence, and the same recognition sequence corresponds to different foreign DNA segment, so closed circle DNA computing model is generalized. For change positive-weighted Hamilton circuit problem, closed circle DNA algorithm is put forward. First, three groups of DNA encoding are encoded for all arcs, and deck groups are designed for all vertices. All possible solutions are composed. Then, the feasible solutions are filtered out by using group detect experiment, and the optimization solutions are obtained by using group insert experiment and electrophoresis experiment. Finally, all optimization solutions are found by using detect experiment. Complexity of algorithm is concluded and validity of DNA algorithm is explained by an example. Three dominances of the closed circle DNA algorithm are analyzed, and characteristics and dominances of group delete experiment are discussed.
摘要：
Currently existing data access object (DAO) patterns have several limitations. First, the interface of the patterns and business objects is tightly-coupled, which affects seriously the dynamic extensibility of software systems. Second, the patterns have duplicated implementation codes, which add to difficulties of system maintenance. To solve these problems, a new DAO pattern with stronger independency and dynamic extensibility is proposed in this paper. Finally, an example is given to illustrate the using process of the new DAO pattern. The greatest advantages of the new DAO pattern are as follows. If any business object is needed to add to the system, we don't have to modify any codes of the class DAO Factory. All we need to do is to modify the mapping file. Furthermore, because we have only one DAO implementation class to accomplish all the data access to business objects, if some SQL statements are needed to be modified, all we need to do is to modify the DAO implementation class but not need to modify any business objects.
关键词：
access control model;attribute;policy;decision;multi-policy supporting
摘要：
Because of the limitations of condition configuration and execution mechanism, the exiting access control models are not flexible and can not support multi-policy. Focusing on this, the paper presents a policy-based access control model (PBAC). Different from the traditional models which restrict session only with subject authorization, PBAC realizes policy-based access control by defining attribute to describe session property, performing a new policy management method that is free from application logic, and advocating an independent access control decision mechanism. As a consequence, PBAC is more flexible on restricting session, and makes great progress on multi-policy supporting. The comparison analysis indicates that PBAC is superior to the current access control models.
关键词：
network threat;risk assessment;Dempster-Shafer theory
摘要：
Current practice for real-time security risk assessment typically takes Intrusion Detection Systems alerts as the only source of risk factor. Their assessment results are more likely to suffer from the impact of false positive alerts in the increasingly complex and severe network security environment. This paper proposes a novel online fusion model for dynamical network risk assessment by using multiple risk factors. The model is composed by three fusion levels. First, an online alert fusion algorithm is proposed and the redundancy of the raw alerts is dramatically reduced. Then, the model employs Dempster-Shafer theory to handle uncertainties and ignorance existed in the multiple risk factors. Threats in different kinds of severity levels are identified. Finally, the whole network risk distribution is dynamically calculated and reported by using HMM approach. Experiments show the effectiveness and validity of our method.
摘要：
In recent years, with the conversion of the dominant teaching theory from behaviorism to constructivism, the body part of the learning process, the learner, is widely concerned. Many scholars at home and abroad and people in the educational circles treat the ability of the self-study and personalized learning as the ultimate goal of education. The rapid development of computer network technology provides the reliable material condition for the implementation of constructivist theory in teaching. The "online learning" technology established on the basis of computer networks is increasingly becoming one of the development directions of education which makes the network teaching, distance teaching possible. In this paper, the author explores the characteristics, the purpose and significance of the research, the theoretical basis and the research design and procedures of the self-study and personalized learning with the knowledge and experience accumulated in the process of research and development of Academic Support System.
摘要：
This paper presents a method of group decision-making based on CBR. This method involves two steps. Firstly, decision-making problems are expressed by cases and the decision tree is created via ID3 algorithm. Then each decision-maker's preference is incorporated via utility theory to attain group consistent preference; and on the basis of the group preference, the similar case is retrieved in the decision tree to get the solution. At the end of the paper, an example is given, which shows that the method is feasible.
关键词：
three dimensional map;interactive;spatial environment;shortest path;animation
摘要：
This paper is to practice the art of three-dimensional map based on a university campus which can be used for tourism. The spatial elements and animated character are initially built in Maya, and exported into Virtools. This paper explores ways to make the system interactive and view in the web using Virtools. This paper also presents a general system architecture which is able to be reused in other three-dimensional maps with a little modification.
摘要：
In order to maximize the network lifetime for target coverage, we propose a Heuristic Greedy Optimum Coverage Algorithm (HG-OCA). In HG-OCA, we first design a network model in which power supplies of sensor nodes follow a normal distribution. Next, we analyze energy model of target coverage, educe three rules to reduce network scale, present the concept of the key target and the prior coverage of key target. Moreover, we choose sensor with most energy utility as active sensor. In the end, we present HG-OCA to extend network lifetime, based on minimizing energy consumption of key target and maximizing energy efficiency of sensor node. Measurement results show that the new algorithm could increase 80% longer network lifetime and achieve more adaptability and stability.
关键词：
The Standard of IEEE754;Random Number Generator;The Seed of RNG;Liner Congruential Generator
摘要：
It's very important to use a good Random Number Generator,because the Rnadom-Number is always used to make encrypt-key adminicular information or init vector in a cipher-system. In this paper, the authors have analysed the Random Number Generator of Vb Vc and .NET. the authors hope this paper will help to make relatively secure Cipher-System.
摘要：
In this paper, through analysis of function and working theory of RISC CPU instruction decoder module, we design instruction decoder module of 32-bit CPU. The instruction decoder includes register file, write back data to register file, sign bit extend, relativity check, and it is simulated on QuartusII successfully.
