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11.
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   
12.
Although it has been only ten years in operations, Yantian International Container Terminals Limited (YICT) has evolved as a world-class container terminal and become the first Chinese port to receive the Best Global Container Port of the Year award for 2005–2006, as well as being designated China's best container terminal in terms of operational efficiency for 2008. A success factor of YICT is its extensive use of IT in managing and enhancing the productivity and services of the port operations. Premised upon Institutional Theory and the organizational mindfulness perspectives (preoccupation with failure and success, reluctance to simplify interpretations, sensitivity to operations, commitment to resilience, and reliance on expertise over formal authority) and using case study methodology, we examined the institutional pressures faced by YICT in its IT management (ITM), and determined how YICT coped with its institutional pressures during its IT development.  相似文献   
13.
Existing Global Data Computation (GDC) protocols for asynchronous systems are round-based algorithms designed for fully connected networks. In this paper, we discuss GDC in asynchronous chordal rings, a non-fully connected network. The virtual links approach to solve the consensus problem may be applied to GDC for non-fully connected networks, but it incurs high message overhead. To reduce the overhead, we propose a new non-round-based GDC protocol for asynchronous chordal rings with perfect failure detectors. The main advantage of the protocol is that there is no notion of rounds. Every process creates two messages initially, with one message traversing in a clockwise direction and visiting each and every process in the chordal ring. The second message traverses in a counterclockwise direction. When there is direct connection between two processes, a message is sent directly. Otherwise, the message is sent via virtual links. When the two messages return, the process decides according to the information maintained by the two messages. The perfect failure detector of a process need only detect the crash of neighboring processes, and the crash information is disseminated to all other processes. Analysis and comparison with two virtual links approaches show that our protocol reduces message complexity significantly.  相似文献   
14.
Universal Access in the Information Society - In recent years, researchers have attempted to shift patient decision aids (PDAs) from paper-based to web-based to increase its accessibility. Insulin...  相似文献   
15.
This paper is focused on designing a distributed adaptive control scheme for a vehicular platoon with unknown bounded velocity/acceleration disturbances and unknown nonlinear dead‐zone inputs. Our aim is to design distributed adaptive controllers based on integral sliding mode control techniques that guarantee practical exponential convergence (i.e., exponential stability of an arbitrarily small neighborhood of zero) of the spacing errors and the string stability of the whole vehicular platoon. The contributions of this paper are that: (i) based on a modified constant time headway policy, the whole vehicular platoon is guaranteed to have string stability despite dead zone inputs; (ii) adaptive compensation terms are constructed to compensate for the time‐variant effects caused by unknown bounded velocity/acceleration disturbances, and unknown dead zone inputs; (iii) an efficient numerical method for avoiding the singularity problem of the control law is also proposed. Numerical simulation results show the validity and advantages of the proposed method are significantly higher traffic density and string stability. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
16.
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   
17.
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   
18.
This paper presents a unified approach to the optimal design of sharp linear-phase finite-impulse-response (FIR) digital filters synthesized using the multistage frequency-response masking (FRM) technique. In this approach, the design of a k-stage FRM filter is achieved in a recursive manner. The minimax design problem arising at each step of the synthesis process is converted into a corresponding weighted least-squares (WLS) problem. The WLS problem is highly nonlinear with respect to the coefficients of the filter. Consequently, it is decomposed into several linear least-squares (LS) problems, each of which can be solved analytically. It is then solved iteratively by using an alternating variable approach. Numerical design examples are included to demonstrate the effectiveness of the method.  相似文献   
19.
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   
20.
Software defined physical layer modems can be considered the new trend in the field of communications. Differently from dedicated hardware, software can be easily modified to implement a large variety of standards on the same platform. The use of software can significantly reduce development costs, but generally comes at the price of an increase in silicon area and power consumption. For different reasons, this price is something that is not always convenient or even possible to pay, as in the case of low-cost ICs implementing a single waveform, or even multi-mode modems embedding legacy IPs already available in hardware. In particular, power consumption overhead can be prohibitive for mobile terminals or in general for battery-powered devices. The very first challenge for a computing fabric to be competitive is to find and implement the right trade-off between flexibility and performance. This was the guideline for the design of the Block Processing Engine (BPE), a template architecture conceived for power-efficient baseband processing. The BPE core feature is a mixed-grain instruction set balancing general-purpose fine-grain instructions with more specific coarse-grain instructions wrapping custom hardware modules. To further limit the power consumption, the BPE also implements instruction-pipelining, variable-size SIMD and multi-task support. To prove the efficiency of such an approach, a dual-mode IEEE 802.11a/p receiver has been implemented.  相似文献   
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