检索结果-内蒙古大学图书馆

IEEE Symposium on Visual Languages and Human Centric Computing (VL/HCC)

作者： Shinji Koka Kenshi Nomaki Koichi Anada Takeo Yaku Department Computer Science and System Analysis Nihon University Tokyo Japan Waseda Research Institute of Science and Engineering Waseda University Tokyo Japan

We discuss tabular forms. It is known in the previous studies that the “octgrid” is a data structure for single layer tabular forms with ruled line preserving algorithms. And the “hexadeci-grid” is known as a data structure for multiply layered tabular forms which is a generalization of the “octgrid”. Our purpose of this paper is to propose a new algorithm based on the “hexadeci-grid” model for editing tabular forms.

关键词：

来源：评论

学校读者我要写书评

暂无评论

XML semantic constraint validation for XML updates: A survey

XML semantic constraint validation for XML updates: A survey

引用

International Conference on Semantic Technology and Information Retrieval (STAIR)

作者： Norfaradilla Wahid Eric Pardede Department of Computer Science and Engineering La Trobe University VIC Australia Faculty of Computer Science and Information System Universiti Tun Hussein Onn Malaysia Batu Pahat Malaysia

XML databases are commonly used for representing data with more complex structures than traditional relational data. Like in any data model, it is very important to ensure that the contents of the database always valid even after any attempt of updates. XML Updates validation is a process of checking the correctness of XML documents, in terms of satisfying their constraints, after updates operations. The validation can be generally categorized into structural and semantic validation. The first validation is to ensure that all XML nodes in the documents conform to structural information in its associated schema. Meanwhile, the second validation checks the integrity constraints of the documents, and it involve various factors such as the functional dependencies, domain constraint, inheritance, etc. In this paper, we provide a preliminary survey of semantic validation w.r.t XML Updates. The work of validation usually applied either upon any attempt of updates or in a scheduled period. We compare the output gain by works in terms of operation of update, the composition, types of constraint, etc. It shows that even though there are abundant of studies in this area, not much work has investigated a complete semantic validation of different semantic constraints. The constraints are still strongly dependent on structural information of documents and lied only on the data access tier of application architecture.

关键词： XML Semantics Data models Transforms Relational databases Object oriented modeling

来源：评论

学校读者我要写书评

暂无评论

ACF comparison of various spreading sequences for T-DMB watermarking system

ACF comparison of various spreading sequences for T-DMB wate...

引用

2011 International Conference on ICT Convergence, ICTC 2011

作者： Lee, Seungho Lee, Junghoon Lee, Yongtae Baek, Myungsun Lim, Bomi Rho, Jungkyu Jeong, Incheol Cha, Jaesang Dept. of Media Eng. Seoul National Univ. of Science and Tech. Seoul Korea Republic of Broadcasting System Research Department Broadcasting and Telecommunication Media Research Division ETRI Korea Republic of Dept. of Computer Science Seokyeong Univ. Seoul Korea Republic of Dept. of Computer and Communication Engineering Sungkonghoe University Seoul Korea Republic of

ISBN: (纸本)9781457712678

This paper compared ACF(Auto Correlation Feature) characteristics for ZCD, Kasami and Golay codes. Sequence codes have been used as a spreading sequence in order to overcome ICI(Inter Code Interference) caused by transmitter and MPI(Multiple Path Interference) in receiver. In this paper, we abstracted characteristics of each spreading code and analyzed the properties of them. © 2011 IEEE.

关键词： Codes (symbols)

来源：评论

学校读者我要写书评

暂无评论

Control of epidemic spreading on complex networks by local traffic dynamics

引用

Physical Review E 2011年第4期84卷 045101(R)-045101(R)页

作者： Han-Xin Yang Wen-Xu Wang Ying-Cheng Lai Yan-Bo Xie Bing-Hong Wang Department of Physics Fuzhou University Fuzhou 350002 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China School of Electrical Computer and Energy Engineering Arizona State University Tempe Arizona 85287 USA Research Center for Complex System Science University of Shanghai for Science and Technology and Shanghai Academy of System Science Shanghai 200093 China

Despite extensive work on traffic dynamics and epidemic spreading on complex networks, the interplay between these two types of dynamical processes has not received adequate attention. We study the effect of local-routing-based traffic dynamics on epidemic spreading. For the case of unbounded node-delivery capacity, where the traffic is free of congestion, we obtain analytic and numerical results indicating that the epidemic threshold can be maximized by an optimal routing protocol. This means that epidemic spreading can be effectively controlled by local traffic dynamics. For the case of bounded delivery capacity, numerical results and qualitative arguments suggest that traffic congestion can suppress epidemic spreading. Our results provide quantitative insight into the nontrivial role of traffic dynamics associated with a local-routing scheme in the epidemic spreading.

关键词： TRAFFIC congestion computer networks PROBABILITY theory computer viruses EMAIL

来源：评论

学校读者我要写书评

暂无评论

RAMC: A RSU-assisted multi-channel coordination MAC protocol for VANET

RAMC: A RSU-assisted multi-channel coordination MAC protocol...

引用

作者： Liu, Kai Guo, Jinhua Lu, Ning Liu, Fuqiang Wang, Xinhong Wang, Ping School of Electronics and Information Engineering Key Laboratory of Embedded System and Service Computing Tongji University 4800 Cao'an Road 201804 Shanghai China Department of Computer and Information Science University of Michigan-Dearborn 4901 Evergreen Rd Dearborn MI 48128 United States

Dedicated Short Range Communication (DSRC) employs one control channel for safety-oriented applications and six service channels for non-safety commercial applications. However, most existing multichannel schemes require all neighboring vehicles periodically (e.g. every 100 milliseconds) tune to the control channel for a full update of safety-oriented data before they can switch to the service channels for non-safety services. The safety exchange interval increases with the increase of traffic density. Consequently, under high traffic densities, the service channels are often completely idle while the control channel is congested. We propose a RSU Assisted Multi-channel Coordination MAC (RAMC) protocol that fully utilizes all channels to provide simultaneous safety and non-safety communications. Within the radio range of a roadside unit (RSU), vehicles are free to tune to any service channel. The RSU monitors all the safety messages being transmitted in both the control and service channels. Periodically, the RSU broadcasts a consolidated traffic view report to all neighboring vehicles in all channels. Therefore, a vehicle can operate in a service channel as long as it needs to achieve high throughput for non-safety applications, while maintaining adequate and timely safety awareness. Our simulation results show that the proposed RAMC protocol consistently achieves very high percentage of non-safety usage, while maintaining high safety message delivery ratios in various traffic density conditions. Copyright © 2011 The Institute of Electronics, Information and Communication Engineers.

关键词： Dedicated short range communications

来源：评论

学校读者我要写书评

暂无评论

Enhanced authentication schemes for intrusion prevention using native language passwords

引用

International Journal of computer science Issues 2011年第4 4-1期8卷 356-362页

作者： Malempati, Sreelatha Mogalla, Shashi Department of Computer Science and Engineering R.V.R. and J.C. College of Engineering Chowdavaram Guntur A.P India Department of Computer Science and System Engineering Andhra University College of Engineering Andhra University Visakhapatnam A.P India

Textual password authentication schemes are vulnerable to attacks like eves dropping, shoulder surfing and hidden cameras. An authentication scheme which integrates graphics and text is resistant to these attacks. Native language passwords are more secure than standard language passwords. Users can remember native language passwords better than any other language, by nature. A shape based textual password authentication scheme using native language of the user is discussed and enhancements are proposed to make the authentication scheme more secure.

关键词： Authentication

来源：评论

学校读者我要写书评

暂无评论

Extracting environmental constraints to make reactive system specifications realizable

Computer Software

引用

computer Software 2011年第3期28卷 132-146页

作者： Hagihara, Shigeki Shimakawa, Masaya Yonezaki, Naoki Kitamura, Yusuke Sekido, Satoshi Department of Computer Science Graduate School of Information Science and Engineering Institute of Technology Japan System Engineering Dept. Sony Business Solutions Corporation Value Creation Division Japan Department of Communications and Integrated Systems Graduate School of Science and Engineering Tokyo Institute of Technology Japan

Many fatal accidents of safety critical reactive systems have occurred in unexpected situations which had not been considered during design and test phases of the systems. To prevent these accidents, reactive systems should be designed to respond appropriately to any requests of any timing from their environments. Verifying this property in specification phase reduces the development costs of safety critical reactive systems. This property of a specification is well known as realizability. If a specification was found not to be realizable, we have to determine the flaws in the unrealizable specification. Unrealizability of a specification arises from arbitrary requirements given by system designers. From a different point of view, it can be thought that the unrealizable specification implicitly imposes a precondition on the behavior of environment, which a system can not control. If it is possible to obtain the precondition in intuitively comprehensive forms, this makes it easy for system designers to understand the cause of flaws in specifications. In this paper, we propose methods for deriving constraints on the behavior of environments, which is implicitly imposed by unrealizable specifications. Instead of realizability, we use strong satisfiability which is a necessary condition for realizability, due to the fact that many practical unrealizable specifications are also strongly unsatisfiable, and strong satisfiability have the advantage of lower complexity for analysis against realizability. These methods derive constraints in propositional linear temporal logic from Büchi automata representing specifications. The expressions of derived constraints are limited to simple and intuitively comprehensive forms where only two temporal operators appear successively. We give proofs for three correctness properties of our methods, i.e. the termination property, the soundness property, and the weakest constraints derivability. We also discuss complexity of our methods. Fi

关键词： Specifications

来源：评论

学校读者我要写书评

暂无评论

Under Uncertainty Trust Estimation through Unknown Agents, in a Multi-valued Trust Environment

Under Uncertainty Trust Estimation through Unknown Agents, i...

引用

International Conference on Tools for Artificial Intelligence (ICTAI)

作者： Sina Honari Brigitte Jaumard Jamal Bentahar Department of Computer Science and Soft. Engineering Concordia University Montreal Canada Department of Computer Science and Soft. Eng Concordia University Montreal Canada Concordia Institute for Information System Engineering Concordia University Montreal Canada

In a world where an increasing number of transactions are made on the web, there is a need for a trust evaluation tool dealing with uncertainty, e.g., for customers interested in evaluating the trustworthiness of an unknown service provider throughout queries to other customers of unknown reliability. In this paper, we propose to estimate the trust of an unknown agent, say a D , through the information given by a group of agents who have interacted with agent a D . This group of agents is assumed to have an unknown reliability. In order to tackle the uncertainty associated with the trust of unknown agents, we suggest to use possibility distributions. We introduce a new certainty metric to measure the degree of agreement of the information reported by the group of agents about agent a D . Fusion rules are then used to estimate the possibility distribution of agent a D 's trust. To the best of our knowledge, this is the first paper that estimates trust, out of empirical data, subject to some uncertainty, in a discrete multi-valued trust environment. Numerical experiments are presented to validate the proposed tools.

关键词： Uncertainty Probability distribution Quality of service Reliability Measurement uncertainty Educational institutions

来源：评论

学校读者我要写书评

暂无评论

Determination of security limits with respect to voltage instability at RTE

Determination of security limits with respect to voltage ins...

引用

IEEE Power and Energy Society General Meeting

作者： Marie-Sophie Balavoine Vincent Sermanson Thierry Van Cutsem "Methods and Support" department of RTE (the French transmission system operator) Dept. of Electrical Engineering and Computer Science of the University of Liege

ISBN: (纸本)9781457710001

This paper reports on the implementation of Voltage Security Assessment tools in the energy management system of RTE, the French transmission system operator. In particular, secure operation limits are determined in voltage sensitive regions. This involves a load increase in the region of concern, covered by a power transfer from various locations throughout the system. The limit is the maximum load power increase such that the system can withstand every contingency of a list. A salient feature of the tool is the use of a simplified, fast time simulation based on the quasi steady-state approximation. This is justified by the presence of controls reacting to the load power increase and the contingency, which makes standard power flow computations inappropriate. The paper also describes the implementation of the tools in the energy management platform of RTE and shows some typical results.

关键词： Voltage instability Long-term dynamics Fast simulation Load power margins Security limits

来源：评论

学校读者我要写书评

暂无评论

A nonlinear model predictive control using a continuation method and a step input constraint

A nonlinear model predictive control using a continuation me...

引用

2011 International Conference on Advanced Mechatronic systems, ICAMechS 2011

作者： Kogiso, Kota Masuda, Shiro Sato, Takao Faculty of System Engineering Tokyo Metropolitan University 6-6 Asahigaoka Hino Tokyo Japan Faculty of Electrical Engineering Mathematics and Computer Science Tokyo Metropolitan University 6-6 Asahigaoka Hino Tokyo Japan Department of Mechanical and Systems Engineering Graduate School of Engineering University of Hyogo 1-3-3 Higashikawasaki-cho Chuo-ku Kobe Hyogo Japan

ISBN: (纸本)9780955529375

The nonlinear model predictive control (MPC) needs to solve a two-point boundary-value problem (TP-BVP) at every sample time based on the receding horizon control strategy. However, solving a nonlinear algebraic equation for the TP-BVP requires high computational load, so developing an efficient computation method of the control law in real-time is a significant issue on the research of the nonlinear model predictive control. This paper proposes an efficient calculation method of the control law for nonlinear MPC. The proposed approach searches an optimal step-type input signal for a given performance index beforehand, then the input signal is successively updated using a continuation method. Hence, it can reduce the computation load because the number of the parameter to be optimized becomes one in the SISO case or the number of the inputs in the MIMO case, and solving TP-BVP can be avoided by a continuation method. In addition, the accuracy of the nonlinear algebraic equation, which gives the optimal condition, keeps well by analytically deriving the updating law of the MPC control law. A numerical example shows that the proposed method can reduce the computation load of the nonlinear MPC, while the accuracy of the optimal conditions given by the nonlinear algebraic equations keeps a tolerance level. © 2011 Intl Journal of Adv Mechatr.

关键词： Model predictive control

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：