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141.
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
142.
143.
Occlusion is a practical technique to measure the visual demand imposed by in-vehicle tasks and to assess whether a task can be resumed having been interrupted. This study describes a number of important factors and variables that need to be controlled to ensure reliability of results. Training of participants on in-vehicle tasks is found to help consistency and five training sessions are required for complex tasks. No significant differences in training with and without occlusion goggles are reported. The required sample size is dependent on the variability of the task; for those investigated an appropriate sample size is found to be 14. For in-vehicle systems that exhibit a delay in response to the user, consistency is improved when these delays are excluded from timing measurements. In terms of calculating the occlusion parameter R, the within-participant basis is most consistent by taking the ratio of the respective median total shutter open time and total task times across trial repetitions completed by one participant on each task under evaluation and, for the purposes of identifying interface designs that exhibit poor resumability, the 85th percentile value is identified as most suitable. Findings from the study are discussed in terms of future application of the occlusion technique to assess in-vehicle information systems (IVIS). 相似文献
144.
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
145.
Kalb J.A. Qiang Guo Xiaoqiang Zhang Yi Li Chornghaur Sow Thompson C.V. 《Journal of microelectromechanical systems》2008,17(5):1094-1103
Phase-change materials have been extensively used for optical data storage in commercial rewritable compact disks and digital video disks. These materials are also widely considered for next-generation phase-change random access memories to replace current Flash memories. We suggest a different application of phase-change materials in optically triggered microactuators. The suggested device consists of a thin film of a phase-change material deposited on a microfabricated cantilever. A laser-induced phase transformation in the film initiates a cantilever deflection since the transformation is accompanied by a large density change. We analyze quantitative criteria for material selection and optimization of device dimensions for the largest possible actuation angles and deflections. The resulting analytical model is both verified numerically and applied experimentally. Furthermore, we show that these cantilevers offer a convenient way to measure film stresses and film strains associated with laser-induced phase transformations. 相似文献
146.
Biddiscombe J Geveci B Martin K Moreland K Thompson D 《IEEE transactions on visualization and computer graphics》2007,13(6):1376-1383
Pipeline architectures provide a versatile and efficient mechanism for constructing visualizations, and they have been implemented in numerous libraries and applications over the past two decades. In addition to allowing developers and users to freely combine algorithms, visualization pipelines have proven to work well when streaming data and scale well on parallel distributed-memory computers. However, current pipeline visualization frameworks have a critical flaw: they are unable to manage time varying data. As data flows through the pipeline, each algorithm has access to only a single snapshot in time of the data. This prevents the implementation of algorithms that do any temporal processing such as particle tracing; plotting over time; or interpolation, fitting, or smoothing of time series data. As data acquisition technology improves, as simulation time-integration techniques become more complex, and as simulations save less frequently and regularly, the ability to analyze the time-behavior of data becomes more important. This paper describes a modification to the traditional pipeline architecture that allows it to accommodate temporal algorithms. Furthermore, the architecture allows temporal algorithms to be used in conjunction with algorithms expecting a single time snapshot, thus simplifying software design and allowing adoption into existing pipeline frameworks. Our architecture also continues to work well in parallel distributed-memory environments. We demonstrate our architecture by modifying the popular VTK framework and exposing the functionality to the ParaView application. We use this framework to apply time-dependent algorithms on large data with a parallel cluster computer and thereby exercise a functionality that previously did not exist. 相似文献
147.
Summary The thermal cure of a monofunctional maleimide N-(4-phenoxy)-phenylmaleimid (1) was examined using differential scanning calorimetry (DSC). The analogous bis-maleimide bis-(4-maleimidophenyl)ether (2) was also analyzed in the same manner for comparison. Polymerization kinetics derived from scanning DSC measurements showed an order of reaction varying between n=1 and 2 for (1), compared to an order of reaction between n=2 and 3 (by multiple linear regression analysis) for (2). The overall enthalpy of polymerization (Ho) for N-(4-phenoxy)-phenylmaleimide (94kJ/mole) agrees well with that obtained for maleimide itself (89kJ/mole) using conventional calorimetric techniques indicating that polymerization appears complete within the timescale of the experiment. In contrast the analogous BMI displays a markedly lower overall polymerization enthalpy (ca. 66kJ/mole) indicating an apparent conversion of only 37%. 相似文献
148.
Ohmic contacts were obtained to p-type Hg0.3Cd0.7Te crystals by metalorganic chemical vapour deposition (MOCVD) of HgTe as an interface material between the crystals and the contacting metal. Deposition at a reduced temperature of 350C did not lead to an obvious change in the material performance. Electronic-transport data are given. Two acceptor levels, at 4.8 and 60 meV above the valence-band edge, were found. 相似文献
149.
Previous investigations of the replacement of silicon by aluminium and nitrogen by oxygen in -silicon nitride have been based primarily on X-ray powder diffraction studies. In the present work this technique is coupled with parallel infra-red studies. X-ray analyses of sialons over a wide composition range confirm previous observations that increasing substitution of aluminium for silicon and nitrogen for oxygen in -silicon nitride is accompanied by an increase in cell size, with no evidence of any other structural modification. Parallel infra-red analyses show shifts in certain of the infra-red absorption bands to lower wavenumbers as the degree of substitution increases. Changes in the infrared spectra at the composition Si2Al4N4O4 indicate structural modifications which are not apparent from the X-ray investigations. It is suggested that these changes are a result of the ordering of the different atom types at this composition. 相似文献
150.
J. D. Thompson M. P. Maley C. Y. Huang J. O. Willis J. L. Smith H. L. Luo 《Journal of Low Temperature Physics》1981,43(3-4):243-261
We have measured the resistance R, magnetoresistance, and magnetization of sintered samples of the compounds Sn
x
Eu1.2–x
Mo6S8, where x = 0, 0.12, 0.24, and 0.48. A large resistance anomaly beginning at T ~ 100 K and extending to low temperatures is found in all of the alloys except x = 0.48, which had a high superconducting transition temperature T
c ~ 11.3 K. The resistance anomaly, which appears to be correlated with the depression of T
c, is also correlated with a large negative magnetoresistance at temperatures T 12 K. For all samples except x = 0.48, that part of the magnetoresistance attributed to spin-flip scattering is proportional to the square of the magnetization M
2 and is 30–40% of R (0) for some samples. Magnetization measurements are consistent with a spin-7/2 paramagnetic behavior of Eu2+ ions when allowance is made for a concentration of 20–30% nonmagnetic (J = 0) Eu3+ ions as determined from Mössbauer measurements. The experimental results are inconsistent with predictions of dilute magnetic alloy Kondo models. We speculate that the resistance anomaly and suppression of T
c for x 0.24 are associated with a semiconductor-like behavior.Work performed under the auspices of the U.S. DOE.Work supported by NSF Research Grant DMR 78-2428. 相似文献