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101.
102.
Many Internet applications use public key technology for security purposes. These applications (i.e. World Wide Web protocols, Internet protocol security, digital signatures, user authentication and E-mail) require a public key infrastructure (PKI) to securely manage public encryption keys for widely distributed users or systems.1 The use of public key technology requires that the user of a public key be confident that the public key belongs to the correct remote subject (i.e. person or system) with which the encryption mechanism will be used.2 This confidence is obtained through the use of public key certificates.2  相似文献   
103.
The objective of this study was to evaluate an auto-instructional preventive programme designed to allow the subjects to identify critical aspects related to their work and musculoskeletal comfort, and provide them with some simple alternatives for controlling the identified problems. The programme was evaluated by 36 secretaries and bank clerks through their symptom perception before and after the programme. The results showed that the symptoms increased in number and severity. The programme seemed to have helped the participants to become aware of the ergonomic problems present in their job and to link these problems to physical symptoms. Self-administered preventive programmes can lead to clearly negative results when applied as the only measure to control musculoskeletal symptoms.  相似文献   
104.
许桢 《测试技术学报》2004,18(Z1):92-96
理论分析表明在镀有金属分光膜的玻璃介质和金属介质构成的几何楔形成的斐索干涉条纹中,相长干涉并不位于相邻的两相消干涉的中央,而是存在一明显偏移,这一偏移与引入几何楔中待测液体的折射率相关.基于该原理,提出了一种新的折射率测量的方法,并对该方进行了实验验证.该方法不需要利用标准液对光学几何量进行标定,测量范围广.  相似文献   
105.
This article provides an overview of the factors that may contribute to the effective term of protection for a pharmaceutical product in the USA––by patent and by FDA market exclusivities, identifies public and commercial sources for collecting relevant patent term and exclusivity data, and provides a strategy for ensuring that the effective term of protection has been calculated accurately.  相似文献   
106.
Remote memory was assessed in persons with HIV-associated dementia (HIV-D), probable Alzheimer's disease (AD), and Huntington's disease (HD) and in healthy controls. The clinical groups were similar in overall dementia severity. Each clinical group exhibited impairments on remote memory tests relative to controls; however, temporally graded memory loss with selective preservation of older information was observed in the AD group but not the HD or HIV-D group. Analysis of cued retrieval indicated a preferential cuing benefit for the HIV-D and HD groups relative to the AD group. The similar pattern of remote memory performance demonstrated by the HIV-D and HD groups is a novel finding and suggests a subcortically mediated retrograde amnesia in HIV-D. The temporally graded pattern and the abnormal cued retrieval performance in the AD group are consistent with a consolidation deficit associated with extrahippocampal (cortical) and hippocampal damage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
108.
This study was performed to characterize pear protease proteolytic activity and investigate the use of pear protease as a meat tenderizer. Pear protease was purified and stabilized by 5% dextrin during lyophilization (dry) or concentration (liquid). Pear protease was further characterized with respect to pH, thermodynamics, and enzyme kinetics. Pear protease was stable at a pH range of 5-8 with an optimum pH of 6.5. From Arrhenius plots, liquid protease showed higher temperature dependency (23.49 kJ/mol) than dry protease (18.62 kJ/mol) due to its higher activation energy. The kcat/Km, catalytic efficiency of enzyme, was similar with 2.9 and 2.7 µM/min with dry and liquid proteases. Pear protease was evaluated for its proteolytic activities with casein and beef myofibrillar proteins by individually and combination with fig and kiwifruit proteases. These result indicated that pear and kiwifruit proteases could be complementary to be a desirable product for meat tenderization.  相似文献   
109.
A highly nonlinear increase in electrical conductivity and concomitant photoemission occurs not only during “flash sintering” but also in presintered, dense specimens. We report results from experiments with dense specimens that show a strong correspondence between the intensity of photoemission and electrical conductivity of specimens under a variety of conditions of the electrical parameters. It is proposed that both properties are related to the concentration of electron–hole pairs generated in such experiments.  相似文献   
110.
Generating sentences from a library of signs implemented through a sparse set of key frames derived from the segmental structure of a phonetic model of ASL has the advantage of flexibility and efficiency, but lacks the lifelike detail of motion capture. These difficulties are compounded when faced with real-time generation and display. This paper describes a technique for automatically adding realism without the expense of manually animating the requisite detail. The new technique layers transparently over and modifies the primary motions dictated by the segmental model and does so with very little computational cost, enabling real-time production and display. The paper also discusses avatar optimizations that can lower the rendering overhead in real-time displays.  相似文献   
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