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51.
The Lorenz system is well known for its ability to produce chaotic motion and the control problem of this system has attracted much attention in recent years. In this paper, control of the Lorenz chaotic systems based on a nonlinear feedback technique is presented. The objective of control is two-fold: one is to drive the system to one of equilibrium points associated with uncontrolled chaotic motion and the other is to let one of the closed-loop system states track a given signal. The controllers designed here are based on exact linearization theory of nonlinear systems and can regulate the closed-loop system states globally to a given point. Finally, illustrative examples show the effectiveness of the proposed design method.  相似文献   
52.
This study examined the influence of perceived enjoyment on pre-service teachers’ intention to use technology, in addition to re-appraising the role of attitude toward use in the Technology Acceptance Model (TAM; Davis, Bagozzi, &; Warshaw, 1989). One hundred and fifty-three participants in Singapore completed a survey questionnaire measuring their responses to five constructs from a research model that was developed specifically for the study. Structural Equation Modeling (SEM) showed that perceived enjoyment was a significant predictor of perceived usefulness, perceived ease of use, and intention to use technology. The findings of this study support the view of Davis et al. (1989) from over 30 years ago that attitude toward use contributes only modestly to the TAM.  相似文献   
53.
There is growing interest in the role and contribution of e-government to the levels of corruption, economic prosperity and environmental degradation of nation states. In this paper, we use publicly available archival data to explore the relationships among them. Results substantiate a significant relationship between (1) e-government maturity and corruption; and (2) e-government maturity, economic prosperity and environmental degradation through the mediating effects of corruption. The findings suggest that while e-government maturity did not contribute to economic prosperity and environmental degradation, its value could be realized indirectly via its impacts on corruption. Our findings contribute to the theoretical discourse on e-government impact by identifying the role of e-government in a country and provide indications to practice on enhancing its economic prosperity and lowering its environmental degradation by managing the levels of e-government maturity and corruption.  相似文献   
54.
Although much research has been done in the area of strategic planning for information systems (IS), relatively less research has focused on the output of the IS planning process, namely, the IS plan. This paper examines the usefulness of IS plans through a field survey of 136 IS executives. Results indicate that IS plans are generally perceived to be useful for supporting business objectives, improving systems integration, exploiting information technology (IT) for competitive advantage, and prioritising IS development projects. Conversely, IS plans are perceived to be less useful for clarifying the role of IS, evaluating IS performance, anticipating surprises and crisis, and adapting to unanticipated situations. Implications of these results are discussed.  相似文献   
55.
Although many developing and developed countries have major initiatives to promote the use of information technology (IT), Singapore is one of the few countries which not only has a comprehensive IT2000 vision, but which is also taking proactive steps to make the vision a reality. This paper examines how Singapore is currently leveraging IT applications to achieve the IT2000 vision. It also explores some of the uses of IT that will be deployed in the near future. Specifically, this paper discusses the use of IT applications to provide one-stop, non-stop government and business services, promote cashless transactions, provide more options for leisure, and facilitate easy commuting.  相似文献   
56.
Bivalency argument is a widely-used technique that employs forward induction to show impossibility results and lower bounds related to consensus. However, for a synchronous distributed system of n processes with up to t potential and f actual crash failures, applying bivalency argument to prove the lower bound for reaching uniform consensus is still an open problem. In this paper, we address this problem by presenting a bivalency proof that the lower bound for reaching uniform consensus is (f+2)-rounds where 0?f?t−2.  相似文献   
57.
The coordination arrival problems of first‐order multi‐agent systems with the arriving structure and the time structure requirements are considered for the cases with no obstacle and obstacle. To describe the distributed coordination arrival problems, we first introduce needed definitions, such as coordination arrival, threat point, and arrival structure. By selecting the estimated value of the arriving time of the agent as variable, we then develop a central estimating algorithm, which is used to construct the arriving protocols. Based on the estimating algorithm, we build and analyze coordination arriving protocols for the proposed coordination arrival problems. Several simulation examples are presented to validate the proposed algorithms. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
58.
We present a liquid‐crystal display (LCD) backlight made of nanoplatelets (NPLs) for the first time. Owing to the narrow emission linewidth of NPLs (8‐12 nm) and quantum dots (QDs), the spectrum exhibits a wide color gamut display with a 139.9% color gamut of National Television System Committee (NTSC) 1953 standard and 104.5% Rec.2020 (ITU‐R Recommendation BT.2020), realizing a truly ultrawide color gamut LCD display.  相似文献   
59.
The Internet, and more recently mobile phones have seen tremendous growth over the past few years. This paper examines the adoption of the Internet and WAP-enabled mobile phones in Singapore. Specifically, we compare users of WAP-enabled mobile phones and non-WAP-enabled mobile phones in terms of profile of Internet users, Internet activities and issues relating to WAP-enabled mobile phones. The results indicate that short messaging system (SMS) and caller ID are popular functions for mobile phone users. Respondent also use the mobile phone for buying cinema/concert tickets and accessing personalised news. These results provide researchers and practitioners with some insights on the adoption of the Internet and WAP-enabled mobile phones. For researchers, such insights would be useful in understanding the adoption phenomenon, while for practitioners, such insights would provide some basis for adopting certain policies to promote adoption.  相似文献   
60.
This paper describes an intelligent diagnostic system for an interconnected distribution network developed to assist the system operator with fault identification during restoration. The intelligent process utilizes only those data available in a standard SCADA system such as the post fault network status, the list of the tripped breakers, main protection alarm, and the conventional event log. The fault diagnostic system is implemented by three independent mechanisms, namely the generic core rule, the generic relay setting inference and the specific post-fault network matching and learning. The generic core rule generates various possible fault locations and the generic relay inference examines whether each possible fault location is logical and valid. The specific network matching compares whether the post fault network and the related tripped breakers are identical to a previous fault event. Test results obtained from two distribution networks confirm that the developed system is practical, reliable and accurate  相似文献   
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