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71.
根据GPRS业务及业务发展情况,对GPRS业务模型进行深入研究,并对GPRS无线网络进行了更深入的探讨。 相似文献
72.
Ferdinando Auricchio Lorenza Petrini 《International journal for numerical methods in engineering》2004,61(6):807-836
An always increasing knowledge on material properties as well as a progressively more sophisticated production technology make shape memory alloys (SMA) extremely interesting for the industrial world. At the same time, SMA devices are typically characterized by complex multi‐axial stress states as well as non‐homogeneous and non‐isothermal conditions both in space and time. This aspect suggests the finite element method as a useful tool to help and improve application design and realization. With this aim, we focus on a three‐dimensional macroscopic thermo‐mechanical model able to reproduce the most significant SMA features (Int. J. Numer. Methods Eng. 2002; 55 : 1255–1264), proposing a simple modification of such a model. However, the suggested modification allows the development of a time‐discrete solution algorithm, which is more effective and robust than the one previously discussed in the literature. We verify the computational tool ability to simulate realistic mechanical boundary value problems with prescribed temperature dependence, studying three SMA applications: a spring actuator, a self‐expanding stent, a coupling device for vacuum tightness. The effectiveness of the model to solve thermo‐mechanical coupled problems will be discussed in a forthcoming work. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
73.
74.
Brown Charlotte; Abe-Kim Jennifer S.; Barrio Concepcion 《Canadian Metallurgical Quarterly》2003,34(1):10
What do health care practitioners need to know about providing adequate care for depressed minority women? This article examined the prevalence of depressive symptoms and clinical depression in ethnic minorities, the extent to which current health service utilization is congruent with needs, and the effectiveness of treatments provided to ethnic minorities in the primary care setting. The impact of ethnic minority women's sociocultural context on symptom expression and help-seeking behavior is also discussed. Finally, the clinical implications for accurate assessment and treatment of ethnic minority women by both medical and mental health practitioners working in the primary care sector are addressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
唐代诗人岑参以边塞诗闻名于中国古代诗坛,同时他的山水写景诗写得也毫不逊色,取得了极高的艺术成就,特别是其清淡、清新、清旷、清丽的“四清”并行的艺术风格尤为突出。由于历史和个人原因,岑参的山水写景诗历来鲜为人知,但这并不能否定其特有的艺术价值。 相似文献
76.
Edward C. Malthouse 《Data mining and knowledge discovery》2007,15(3):383-402
This paper discusses a new application of data mining, quantifying the importance of responding to trigger events with reactive
contacts. Trigger events happen during a customer’s lifecycle and indicate some change in the relationship with the company.
If detected early, the company can respond to the problem and retain the customer; otherwise the customer may switch to another
company. It is usually easy to identify many potential trigger events. What is needed is a way of prioritizing which events
demand interventions. We conceptualize the trigger event problem and show how survival analysis can be used to quantify the
importance of addressing various trigger events. The method is illustrated on four real data sets from different industries
and countries. 相似文献
77.
Susskind Alex M.; Kacmar K. Michele; Borchgrevink Carl P. 《Canadian Metallurgical Quarterly》2003,88(1):179
The authors proposed and tested a model describing the relationship between customer service providers' perceptions and attitudes toward their service-related duties and their customers' perceptions of satisfaction with their service experiences. Results indicated that the perception of having standards for service delivery in an organization is strongly related to line-level employees' perceptions of support from coworkers and supervisors. Perceived support from coworker, was significantly related to service providers' customer orientation, whereas perceived support from supervisors showed a weaker relationship to a customer orientation. Ultimately, service providers' customer orientation was strongly related to customers' satisfaction with service. Finally, a set of post hoc analyses indicated that coworker and supervisory support explained a greater proportion of incremental variance in the model than did perceived organizational support alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Boundary objects are a critical, but understudied, theoretical construct in CSCW. Through a field study of aircraft technical
support, we examined the role of boundary objects in the practical achievement of safety by service engineers. Their resolution
of repair requests was preserved in the organization’s memory via three compound boundary objects. These crystallizations
did not manifest a static interpretation, but instead were continually reinterpreted in light of meta-negotiations. This suggests
design implications for organizational memory systems which can more fluidly represent the meta-negotiations surrounding boundary
objects. 相似文献
79.
利用光学方法测量气体状态参数的关键在于确定气体折射率场的变化。光线通过稳定的非均匀折射率场时发生偏折,并且在强折射对称场中会产生交叉,使得条纹位移量的判读困难。本文首先分析了光线在轴对称折射率场中的偏折效应,在此基础上,给出了一种利用成像透镜对强折射轴对称场中折射率的干涉再现方法。该方法与其它方法相比较能够精确地确定折射率n(r)的值。 相似文献
80.
企业办社会虽与市场经济的客观要求相悖,但石油企业大量办社会的事实仍揭示了所具备的理性面。认为国家作为不受所有者监督的代理者对石油企业的要求,石油企业的行业特性以及在传统体制下长期运作所成的定热是石油企业办社会的主要原因。 相似文献