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71.
目前,网络的发展极大推动了人类文明的进步,网络犯罪问题也络绎不绝的出现,而且呈现出平民化、反社会化、加速化、恶性化的特点,因此越来越成为社会关注的重点问题。网络犯罪作为新世纪各国共同面临的社会问题,理应也从社会学角度出发进行研究分析,本文试图应用社会解体理论,从网络犯罪所处的"虚拟社会"出发,探究其形成的原因,并提出相应的对策。  相似文献   
72.
In this paper, several recent theoretical conceptions of technology-mediated education are examined and a study of 2159 online learners is presented. The study validates an instrument designed to measure teaching, social, and cognitive presence indicative of a community of learners within the community of inquiry (CoI) framework [Garrison, D. R., Anderson, T., & Archer, W. (2000). Critical inquiry in a text-based environment: Computer conferencing in higher education. The Internet and Higher Education, 2, 1–19; Garrison, D. R., Anderson, T., & Archer, W. (2001). Critical thinking, cognitive presence, and computer conferencing in distance education. American Journal of Distance Education, 15(1), 7–23]. Results indicate that the survey items cohere into interpretable factors that represent the intended constructs. Further it was determined through structural equation modeling that 70% of the variance in the online students’ levels of cognitive presence, a multivariate measure of learning, can be modeled based on their reports of their instructors’ skills in fostering teaching presence and their own abilities to establish a sense of social presence. Additional analysis identifies more details of the relationship between learner understandings of teaching and social presence and its impact on their cognitive presence. Implications for online teaching, policy, and faculty development are discussed.  相似文献   
73.
Despite much research interest, effective retention of IT professionals has proved difficult for many public sector organizations. By concentrating on intention to leave, researchers may not have provided a clear way to formulate effective retention strategies. Consequently, we used intention to stay as an alternative lens to identify factors that can reduce turnover of IT professionals. Our findings indicated that attitudes, perceived behavioral control (PBC), and identification with the organization all had a statistically significant relationship with intention to stay; attitude was the strongest. It was concluded that existing retention strategies needed to be refocused on the issues that make IT staff stay; a number of practical recommendations for IT managers are presented.  相似文献   
74.
张源 《自动化信息》2010,(10):49-50,53
在图像传输的过程中,图像加密技术起着重要作用。本文介绍了目前常用的图像加密方法、加密技术的发展现状,同时还介绍了图像加密方面的新技术、新方法,并阐述了图像加密技术的发展趋势。  相似文献   
75.
Given a list of n items and a function defined over sub-lists, we study the space required for computing the function for arbitrary sub-lists in constant time.For the function mode we improve the previously known space bound O(n2/logn) to O(n2loglogn/log2n) words.For median the space bound is improved to O(n2loglog2n/log2n) words from O(n2⋅log(k)n/logn), where k is an arbitrary constant and log(k) is the iterated logarithm.  相似文献   
76.
NTRU算法是一种基于环的公开密钥体制,与RSA和ECC等典型的加密算法相比,在安全性和速度方面具有明显的优势。分析目前比较成熟的攻击NTRU方法,从安全的角度,根据不同的应用场合,给出NTRU加密参数选择方法,减少选择NTRU参数的盲目性,达到提高算法的执行速度、减少占用系统资源的目的。  相似文献   
77.
The short product life cycle of information and communication technology (ICT) applications makes it critical for developers to expedite the diffusion process by reducing user resistance. At the individual level, the adoption of an ICT application largely depends on how a person is ready to use the computerized tool in place of the corresponding traditional method for a certain purpose. To find out how to facilitate the transition, this study investigates the human choice behavior involved in technology adoption with the Activity Theory that allows for the inclusion of different tools in one unit of analysis. The understanding of user situated experiences from the activity perspective leads to hypothesized relationships between user-, tool- and task-related factors and the dependent variable in terms of tool readiness. The empirical results support that tool experiences have stronger effects on specific tool readiness at the within-subject level, user characteristics have weaker effects on general tool readiness at the between-subject level, and task situations influence both levels of tool readiness. The findings provide insights on how to facilitate innovation diffusion for different tools, tasks and users.  相似文献   
78.
In this study, we examine digital game preferences by identifying game dynamics, i.e. player–game interaction modes, of 700 contemporary digital games, and players' (N = 1717) desire to play games with specific types of dynamics. Based on statistical analysis of the data, 5 game dynamics preference categories (“assault,” “manage,” “journey,” “care,” and “coordinate”) and 7 player types were revealed. The results show that identifying player types requires including both preferred and undesired game dynamics categories in the analysis. The findings unveil digital gaming as a more multifaceted phenomenon than common stereotypes suggest. The original game preferences model we present in this study can be conceptualized as a complementary approach for motivations to play and player behavior studies.  相似文献   
79.
The rapid evolution of new service systems raises crucial challenges for service design and requires effective methods. This study depicts a conceptual service design framework, called design-oriented systematic inventive thinking (DSIT) approach, which can be applied in different problem contexts. DSIT is presented as a new systematic and collaborative intelligence approach for creating and evaluating complex service systems using multi-criteria data analytics. DSIT synthesizes the current field of TRIZ service-design knowledge system and the emerging area of non-TRIZ service-design knowledge system. DSIT enables integrated development of service offerings at four dimensions and provides the matching integrated service design approach for each dimension. Four types of service design approaches are conceptualized as “human-independent service engineering,” “problem-clarified service engineering,” “solution-converged service engineering,” and “designing for service.” A new service computer-aided design system (service CAD) named DSIT explorer is developed consisting of customization, compatibility, and extensiveness of DSIT modules. A pervasive and smart collaborative service system (i.e., the smart MOS burger service solution) designed using DSIT explorer is illustrated. DSIT is a holistic, interdisciplinary, and collaborative service design concept, which is incorporated into a collaborative and intelligent service CAD framework to enable systematic inventive thinking throughout phases of service design lifecycle from problem definition, problem resolution, to solution evaluation.  相似文献   
80.
就业是社会及其关注的问题,也是高校一项重要的工作。本文设计的高校就业服务信息门户系统的目的是完善高校就业服务工作,将学生、用人单位、就业政策和高校的信息有效的进行结合和对接。本文从技术支持、功能设计、数据库设计和用户界面几方面对系统的设计进行了详细的阐述。  相似文献   
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