Studies on Complexation of ATMP, PBTCA, PAA and PMAAA with Ca^(2+) in Aqueous Solutions

By means of acid-base potentiometric titration and the advanced BEST computer program developed by Martell et al., the deprotonation constants of four inhibitors[Aminotrimethylenephosphoinic acid(ATMP), 2-phosphino-tutane-1,2,4-tricarboxylic acid(PBTCA), polyacrylic acid(PAA, M_w=2000), poly(maleic, acrylic) acid(PMAAA, M_w=3000)], and the stability constants of the complexes of these inhibitors with Ca 2+ have been determined. And the distribution curves of ATMP at different pH values in aqueous solutions have also been given out. The result of this study can be applied to explaining the inhibition mechanism.

A Content-Based Parallel Image Retrieval System on Cluster Architectures

We propose a content-based parallel image retrieval system to achieve high responding ability. Our system is developed on cluster architectures. It has several retrieval. servers to supply the service of content-based image retrieval. It adopts the Browser/Server (B/S) mode. The users could visit our system though web pages. It uses the symmetrical color-spatial features (SCSF) to represent the content of an image. The SCSF is effective and efficient for image matching because it is independent of image distortion such as rotation and flip as well as it increases the matching accuracy. The SCSF was organized by M-tree, which could speedup the searching procedure. Our experiments show that the image matching is quickly and efficiently with the use of SCSF. And with the support of several retrieval servers, the system could respond to many users at mean time. Key words content-based image retrieval - cluster architecture - color-spatial feature - B/S mode - task parallel - WWW - Internet CLC number TP391 Foundation item: Supported by the National Natural Science Foundation of China (60173058)Biography: ZHOU Bing (1975-), male, Ph. D candidate, reseach direction: data mining, content-based image retrieval.

Mining Interesting Knowledge from Web-Log

Web-log contains a lot of information related with user activities on the Internet. How to mine user browsing interest patterns effectively is an important and challengeable research topic. On the analysis of the present algorithm’s advantages and disadvantages we propose a new concept: support-interest. Its key insight is that visitor will backtrack if they do not find the information where they expect. And the point from where they backtrack is the expected location for the page. We present User Access Matrix and the corresponding algorithm for discovering such expected locations that can handle page caching by the browser. Since the URL-URL matrix is a sparse matrix which can be represented by List of 3-tuples, we can mine user preferred sub-paths from the computation of this matrix. Accordingly, all the sub-paths are merged, and user preferred paths are formed. Experiments showed that it was accurate and scalable. It’s suitable for website based application, such as to optimize website’s topological structure or to design personalized services. Key words Web Mining - user preferred path - Web-log - support-interest - personalized services CLC number TP 391 Foundation item: Supported by the National High Technology Development (863 program of China) (2001AA113182)Biography: ZHOU Hong-fang (1976-), female.Ph. D candidate, research direction: data mining and knowledge discovery in databases.

Web-Based Information Systems and Applications: A Survey

Biography: XU Bao-wen(1961-), male, Ph.D. Professor, research direction: programming language, software engineering, Web-based technology, etc.

Improved DOA Estimation Algorithm with Sensor Array Perturbations for CDMA System

An improved direction of arrival (DOA) estimation algorithm with sensor gain and phase uncertainties for synchronous code division multiple access(CDMA) system with decorrelator is presented. Through decorrelating processing DOAs of the desired users can be estimated independently and all other resolved signal interferences are eliminated. Emphasis is directed to applications in which sensor gain and phase are perturbed that often happen actually. It is shown that improved DOA estimation can be achieved for decoupled signals by gain and phase pre estimation procedures.

Study of component-ware & application software framework based decision support system development

The view that the traditional method of DSS development is outdated, which results to the diversiform disadvantages of DSS product. Therefore the ideas of application software framework based development to the generation process of DSS is introduced and a modified flow chat of DSS development is proposed. Moreover, a formal description of the DSS software framework and its development is given. The analysis results indicates that not only does the new development flow ensure the DSS development global stability but also improves the software reusability level of the development process.

Wavelet transform element of SAW type

This paper proposes to use substrate materials of small electromechanical coupling coefficient k2 (such as X-112YLiTaO3) to manufacture wavelet transform element of SAW type so as to reduce finger reflections, i.e. to reduce the error of wavelet transform element of SAW type. And it is concluded that the smaller the center frequency of the transmitting IDT of wavelet type, the smaller the error. We suggest to choose substrate material with electromechanica coupling coefficient smaller than that of X-112Y LiTaO3 in the manufacture of the transmitting IDTs of wavelet type and the receiving IDTs at center frequencies above 100MHZ, so as to reduce the errors of the transmitting IDTs of wavelet type and the receiving IDTs at center frequencies above 100MHZ.

A Cooperative QoS Management Scheme Based on DiffServ Network for Real-Time Service

In this paper,an improved scheme based on DiffServ network is proposed to provide a decentralized coopera-tive QoS management for real-time services'admission control and resources'monitoring.The proposed scheme consists of aQoS Control Server(QoSCS),a Service Management Server(SMS),a Network Management Server(NMS)and routersin the concerned management domain.When an application asks for a service with specific QoS requirements,a series ofcooperation are initiated among these components by means of a suit of signaling protocol.Once a service is admitted,itcan provide required QoS services more effectively than original DiffServ network.Monitoring per-flow states are movedfrom edge routers to the QoSCS server.The prototype implementation and experimental results show that this scheme canprovide enhanced manageability and scalability for providing per-flow management in such a distributed way.

Improving Throughput For TCP Vegas

To slove the problem that the implementation of Transmission Control Protocol (TCP) Vegas does not consider the impact of TCP's segment size on Round-Trip Time (RTT) while calculating RTT and the smallest RTT (base _rtt), this paper proposes a modified congestion control mechanism for TCP Vegas. It first groups segments on the basis of segments size and updates base _rtt based on groups. In congestion avoidance phase, TCP Vegas changes its window size according to the measured RTT of the segment corresponding to the latest received ACK and the base _rtt retrieved from the group that the segment belongs to. Simulations illustrate that the enhanced TCP Vegas can achieve higher throughput up to 40 percent.

PREDICTING CHAOTIC TIME SERIES WITH IMPROVED LOCAL APPROXIMATIONS

In this paper,new approaches for chaotic time series prediction are introduced.We first summarize and evaluate the existing local prediction models,then propose optimization models and new algorithms to modify procedures of local approximations.The modification to the choice of sample sets is given,and the zeroth-order approximation is improved by a linear programming method.Four procedures of first-order approximation are compared,and corresponding modified methods are given.Lastly,the idea of nonlinear feedback to raise predicting accuracy is put forward.In the end,we discuss two important examples,i.e.Lorenz system and RSssler system,and the simulation experiments indicate that the modified algorithms are effective.