关于超二次Hamilton系统周期解的注记

用极小极大方法得到了一类超二次一阶Hamilton系统的周期解.     

α-相对抛物仿射球的Bernstein性质

设y:M→An+1是一个局部严格凸的超曲面,由定义在一个凸域ΩAn上的严格凸函数xn+1=f(x1,x2,…,xn)给出.考虑M上的α-相对度量Gα=ρα∑2fxixjdxidxj,我们研究关于度量Gα完备的α-相对抛物仿射球M得到:若其α-Ricci曲率有下界,则M一定是椭圆抛物面.     

An empirical investigation of factors influencing the adoption of data mining tools

Previous studies explored the adoption of various information technologies. However, there is little empirical research on factors influencing the adoption of data mining tools (DMTs), particularly at an individual level. This study investigates how users perceive and adopt DMTs to broaden practical knowledge for the business intelligence community. First, this study develops a theoretical model based on the Technology Acceptance Model 3, and then examines its perceived usefulness, perceived ease of use, and its ability to explain users’ intentions to use DMTs. The model's determinants include 4 categories: the task-oriented dimension (job relevance, output quality, result demonstrability, response time, and format), control beliefs (computer self-efficacy and perceptions of external control), emotion (computer anxiety), and intrinsic motivation (computer playfulness). This study also surveys the moderating effect of experience and output quality on the determinants of DMT adoption and use. An empirical study involving 206 DMT users was conducted to evaluate the model using structural equation modeling. Results demonstrate that the proposed model explains 58% of the variance. The findings of this study have interesting implications with respect to DMT adoption, both for researchers and practitioners.     

信息与计算科学专业的信号处理课程改革

信号与系统和数字信号处理是很多工科专业的核心课程．直接将其教学方案应用于信息与计算科学专业将会带来很多不便。本文基于华北水利水电学院的专业课程改革,通过对专业培养方案中的授课内容探讨以及市场上的教材分析,结合专业自身特点,建立了一套适用于本专业的信号处理课程理论培养体系。该体系在减少学时的基础上．能够顺利完成所有知识点的教学,符合专业培养要求。     

Information systems and sustainable supply chain management towards a more sustainable society: Where we are and where we are going

The objectives of this study are to identify and systematize scholarly articles on the use of information system to support sustainable supply chain management and to suggest future research opportunities. Therefore, a structured literature review was conducted. The most relevant studies identified were classified and categorized into seven dimensions: research context, research focus, research method, sector analyzed, information system (IS) beneficiaries, relationship between IS and green supply chain practices, and performance benefits. The main authors and articles on this particular topic were identified. In addition, it was concluded that IS is an important support tool for sustainable supply chain management practices since it brings benefits to the organization, suppliers, and customers. Furthermore, IS positively influences the operational, financial, and environmental performance of the organization. However, further advances in the literature are still needed. The major contribution of this research is related to the recommendations that provide opportunities for future research.     

Modular designs and integrating practices: Managing collaboration through coordination and cooperation

Collaboration in large-scale projects introduces challenges involving both coordination (the ability to collaborate) as well as cooperation (the willingness to do so). Existing research has shown how modular designs can improve coordination by locating interdependencies within rather than between different modules. Based on an in-depth case study of collaboration in a large-scale infrastructure project, our study highlights an effect of modularity on collaboration that previously has been overlooked. Specifically, we show that while modular designs may help overcome coordination challenges by reducing interdependencies between modules, they can in turn hamper collaboration by emphasizing specialization within modules. Therefore, though existing work typically perceives modularity and integration as opposites, we clarify how they can also act as complements. In particular, we show how firms need to complement modular designs with integrating practices that stimulate cooperation. Overall, we contribute to the literature on collaboration and modularity by explaining when and how organizations can combine modularity and integration.     

Taylor's decomposition on four points for solving third-order linear time-varying systems

In the present paper, the use of three-step difference schemes generated by Taylor's decomposition on four points for the numerical solutions of third-order time-varying linear dynamical systems is presented. The method is illustrated for the numerical analysis of an up-converter used in communication systems.     

Data Mining to Combat Terrorism and the Roots of Privacy Concerns

Recently, there has been a heavy debate in the US about the government’s use of data mining in its fight against terrorism. Privacy concerns in fact led the Congress to terminate the funding of TIA, a program for advanced information technology to be used in the combat of terrorism. The arguments put forward in this debate, more specifically those found in the main report and minority report by the TAPAC established by the Secretary of Defense to examine the TIA issue, will be analysed to trace the deeper roots of this controversy. This analysis will in turn be used as a test case to examine the adequacy of the usual theoretical frameworks for these kinds of issues, in particular the notion of privacy. Whereas the dominant theoretical framing of the notion of privacy turns around access to information, most of the core arguments in the debate do not fit in this kind of framework. The basic disagreements in the controversy are not about mere access, they involve both access and use. Furthermore, whereas the issue of access by itself refers to a more or less static situation, the real disagreements much more concern the organisational dynamics of the use of information, the mechanisms in the organisation that control these dynamics, and the awareness present within the organisation of the ‘social risks’ these dynamics represent. The bottom line question is whether the assessment of these gives sufficient reason for trust.     

Output feedback stabilization for symmetric control systems

This work is devoted to the study of symmetric control systems. It establishes a relation between internal symmetry and external one for a linear invariant control system having n real simple poles. The symmetric stabilization problem is studied using a symmetric feedback gain such that the output control stabilizes the closed-loop system. A necessary and sufficient condition is given to solve this stabilization problem for a symmetric control system (A,B,C) and a generalized symmetric control system (E,A,B,C).