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41.
Kuo‐Hsiung Wang Tzong‐Ming Wu Yeng‐Fong Shih Chien‐Ming Huang 《Polymer Engineering and Science》2008,48(9):1833-1839
The water bamboo husk is one of major agricultural wastes in Taiwan. In this study, the powder obtained from the water bamboo husk was added to poly(lactic acid) (PLA) to form novel reinforced biodegradable composites. Morphologies, mechanical properties, and heat resistance of these water bamboo powder reinforced composites were investigated. The results indicate that the char yields were increased as plant powder was incorporated to PLA. In addition, the mechanical properties were also enhanced due to the addition of powders. The increments of storage moduli of PLA were about 50–200%. Moreover, the increments of loss moduli of PLA were about 70–200%. On the other hand, the Tg of PLA was slightly decreased by the addition of powder, and this may improve the brittle characteristics of PLA. Furthermore, this type of reinforced PLA would be more environmental friendly than the artificial additive‐reinforced one. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers 相似文献
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Heloisa Martins Shih Mitchell M Tseng 《International Journal of Project Management》1996,14(6):373-378
In this paper the application of workflow technology to monitor, control and coordinate business processes and projects is proposed. The conceptual characteristics of processes and projects as well as their management needs in the functions of planning, execution, monitoring and control are compared. The general design of the proposed system is then developed, with an application example. The proposed monitoring and control system provides proactive tracking of the flow of work and information, and of the utilization and commitment of resources. The design supports hierarchical management of the project and/or business process, allowing concerned persons to visualize and to utilize it in different levels of abstraction, as necessary. The application of workflow technology also provides additional benefits in facilitating communication, documentation and re-utilization. 相似文献
45.
Reduction of optical proximity effects (OPE), at deep uv wavelength of 248nm, caused by the variation of stepper lens operating conditions is investigated. It is shown that many of these effects, which increase as the Rayleigh limit is approached, can be minimised, and in many cases eliminated, by suitable choice of lens numerical aperture (NA) and partial coherence (sigma, σ).
Application of these results should enable the user of advanced wafer steppers to carry out high resolution lithography with a minimum of time consuming optical proximity correction (OPC). 相似文献
46.
A structural model of science achievement and attitude: An extension to high school. 总被引:1,自引:0,他引:1
A previous structural model of Walberg's theory of educational productivity (A. J. Reynolds and H. J. Walberg, 1991) was tested with a national probability sample of 2,535 10th graders for science achievement and attitude. Using data from the Longitudinal Study of American Youth, a 3-wave design incorporated information from students, teachers, and parents. Results indicate that a revised mediated-effects model fit the data best and accounted for substantial variance in Grade 11 science achievement (56%) and attitude (44%). The variables prior achievement, home environment, exposure to mass media through reading, and instructional time had the greatest total effects on science achievement. Prior attitude, home environment, motivation, and prior achievement made the greatest total contributions to science attitude. Although there were different weightings of the factors between the present study and Reynolds and Walberg (1991), both studies support a mediated-effects model of educational productivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Language-level support for object persistence frees programmers from having to confront a broad class of database issues from within their applications. By virtue of its metaobject protocol, CLOS is a language whose semantics can be tailored by individual programmers. We used the metaobject protocol to extend CLOS with support for object persistence. Our goal was to obtain a version of CLOS with persistence to which we could easily port a commercial geometric CAD modeling system. We describe the design and implementation of our persistence extension and highlight the strengths and weaknesses exhibited by the CLOS metaobject protocol during our experiment. For many aspects of the implementation we found that the metaobject protocol was ideal. In other cases we had to choose among paying a large performance penalty, extending the protocol, and bypassing the protocol by modifying the language implementation directly. 相似文献
49.
Avants S. Kelly; Margolin Arthur; Kosten Thomas R.; Rounsaville Bruce J.; Schottenfeld Richard S. 《Canadian Metallurgical Quarterly》1998,66(6):924
In response to a need to match drug users to the most appropriate and cost-effective level of care, it was hypothesized that socially anxious methadone-maintained patients would attain greater benefit from coping skills training provided in the context of a low-intensity enhanced standard methadone maintenance intervention (E-STD) than in the context of a high-intensity, socially demanding day treatment program (DTP). Social anxiety was assessed in 307 methadone-maintained patients using the Social Anxiety and Distress Scale prior to randomization to either E-STD or DTP. The hypothesis was supported: Socially anxious patients were drug free longer during treatment, were more likely to be abstinent at treatment completion, and had greater reductions in HIV risk behaviors if assigned to the lower intensity intervention, which was provided at ? the cost of the DTP. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
McKeon J.B. Chindalore G. Hareland S.A. Shih W.-K. Wang C. Tasch A.F. Jr. Maziar C.M. 《Electron Device Letters, IEEE》1997,18(5):200-202
This letter presents for the first time, the experimentally determined majority carrier mobilities in the accumulation layer of a MOSFET for both p-type and n-type channel doping for a wide range of doping concentrations. The measured carrier mobility is observed to follow a universal behavior at high transverse fields, similar to that observed for minority carriers in MOS inversion layers. At the higher doping levels, the effective mobility for majority carriers at low to moderate transverse fields is found to be very close to the bulk mobility. This is believed to be due to carrier screening of the ionized impurity scattering which dominates at the higher doping concentrations 相似文献