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41.
《Computers & Mathematics with Applications》2007,53(6):961-971
In this paper, we prove a common fixed point theorem for a pair of weakly compatible mappings. The result is applied to prove the existence of solution of system of nonlinear integral equations. Our theorems extend and improve several known results. 相似文献
42.
《Composites Part B》2007,38(5-6):732-738
The reinforced concrete spans of a bridge subjected to extreme vehicular loads are investigated and retrofitted with carbon fiber reinforced polymer (CFRP) laminates. A finite element model of the bridge superstructure was created to determine the forces resulting from extreme loads. A moment–curvature analysis was subsequently carried out to investigate the flexural characteristics of the reinforced concrete sections prior to and after strengthening with CFRP laminates. The analytical modeling concluded that significant strength can be gained at the ultimate limit state, while relatively small increase in strength is observed at service load levels. The increase in flexural resistance at ultimate does provide an adequate margin of safety against further overloading. The analytical investigation and the retrofitting work are presented herein. 相似文献
43.
44.
F. Javier Lerch Deborah J. Ballou Donald E. Harter 《Annals of Software Engineering》1997,3(1):345-366
We describe the use of simulation‐based experiments to assess the computer support needs of automation supervisors in the United States Postal Service (USPS). Because of the high cost of the proposed system, the inability of supervisors to articulate their computer support needs, and the infeasibility of direct experimentation in the actual work environment, we used a simulation to study end‐user decision making, and to experiment with alternative computer support capabilities. In Phase One we investigated differences between expert and novice information search and decision strategies in the existing work environment. In Phase Two, we tested the impact of computer support features on performance. The empirical results of the two experiments showed how to differentially support experts and novices, and the effectiveness of proposed information systems before they were built. The paper concludes by examining the implications of the project for the software requirements engineering community. 相似文献
45.
《Energy》2005,30(8):1317-1328
Wood is a prospective material against the problems of mineral resource shortage and global warming from the viewpoint of sustainable development. The continuous cycle of felling, planting and growing of trees is essential prerequisite for sustainability. The engineering evaluation of advantages of wood can increase its use more widely as a substitute for other industrial materials and save the finite mineral resources. The increase of wood use can support the continuous cycle for the sustainable forestry as an industry. This paper treats good tactile warmth of wood as one of its advantages. The relationship between contact surface temperature and thermal effusivity is derived from the theoretical analysis of governing heat transfer phenomenon on tactile warmth. Some knowledge on tactile warmth of wood is reviewed with these physical properties. The sensory tactile warmth of wood has a high and positive linear correlation with the logarithm of the contact surface temperature. The materials with lower thermal effusivity feel warmer than the ones with higher thermal effusivity. The relationship between contact surface temperature and thermal effusivity explains rationally why each wood has a large difference of tactile warmth in spite of their small difference of material properties. It also explains the reason why wood has good tactile warmth regardless of seasons against metals, which feel too hot in summer and too cold in winter to touch. The contact surface temperature and the thermal effusivity are proposed as engineering measures to evaluate the tactile warmth of wood and other materials. 相似文献
46.
This article considers the nature of online religion by examining the websites and religious counseling activities conducted by new Japanese religions. Beginning with an overview of the widespread use of the Internet in Japan and its use in religion, the article examines the cultural and social factors that keep the religious use of the Internet from becoming as pervasive in Japan as it is in the U.S. The article then describes a website with elements of online religion and the Internet-based religious counseling services being provided by ministers of the new Shintō-derived religions of Konkōkyō and Tenrikyō. These activities have successfully given some people who need religious assistance access to religious teaching. In concluding, the article examines the reasons for the success of these efforts, as well as the reasons why they have not expanded in scope, in light of the cultural and organizational advantages and disadvantages that affect Internet use. 相似文献
47.
《Computers in Industry》2007,58(8-9):844-854
This paper examines the effectiveness of the implementation of enterprise resource planning (ERP) in improving service quality in the Taiwanese semiconductor industry by assessing the expectations and the perceptions of service quality from the perspectives of both upstream manufacturers and downstream customers. The study first establishes a modified service quality gap model incorporating: (i) the downstream customers’ expectations and perceptions, and (ii) the upstream manufacturers’ perceptions of the customers’ expectations and perceptions. An empirical study by questionnaire survey is then undertaken to investigate the gaps proposed in the research model. The results show that service quality gaps do exist in the Taiwanese semiconductor industry between upstream manufacturers that are implementing ERP and their downstream customers. The study shows that the proposed model provides valuable guidance to manufacturers with respect to the prevention, detection, and elimination of the demonstrated service quality gaps. The model thus helps manufacturers to evaluate the contribution of various ERP modules to improved customer satisfaction with service quality and also provides guidance on improvement strategies to enhance service quality by eliminating quality gaps. 相似文献
48.
电视监控系统是一种典型的分布式计算机信号采集系统。为了提高监控的范围和效果,云台控制器的优劣直接影响监控的范围和效果,因此对云台控制器的设计具有重要的意义。本系统采用串型通信,通过Modbus协议把控制信号输入单片机,经过对AT89S52单片机的编程,从而对八路继电器输出进行控制。系统不仅结构简单,而且还可以方便的对镜头、防护罩的控制进行扩展,功能强大,可以广泛应用于电视监控系统中的云台控制。 相似文献
49.
目前大多数分布式存储系统采用静态备份机制保证系统的高可靠性,灵活性差,不适合系统规模及用户访问量不断变化的存储系统.因此提出一种基于用户行为分析的动态备份机制,通过分析用户行为获得相关信息来动态改变备份数量及确定备份位置,具有较强的灵活性,适合大规模的分布式存储系统;实现动态备份系统将其应用于已建立的科技信息数据中心.通过实验分析表明,该动态备份机制能提高系统的可靠性。 相似文献
50.
The paper suggests a new methodology for secure cyber–physical systems design. The proposed methodology consists of two main cycles. The main goal of the first cycle is in design of the system model, while the second one is about development of the system prototype. The key idea of the methodology is in providing of the most rational solutions that are improving the security of cyber–physical systems. Such solutions are called alternatives and built according to functional requirements and non-functional limitations to the system. Each cycle of the methodology consists of the verification process and seven stages that are associated with the used cyber–physical system model. The objective of the verification process is in checking of constructed models and prototypes in terms of their correctness and compatibility. The model represents cyber–physical systems as sets of building blocks with network between them, takes elements internal structure into account and allows direct and reverse transformations. The novelty of the suggested methodology is in the combination of design, development and verification techniques within a single approach. To provide an example of the design methodology application, in this paper it is used to improve the semi-natural model of the railway infrastructure. 相似文献