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排序方式: 共有5626条查询结果,搜索用时 15 毫秒
21.
基于NGOSS体系结构的服务等级协定管理框架 总被引:2,自引:2,他引:0
文章在介绍新一代运营支撑系统体系结构和电信运营图的基础上,详细讨论了基于新一代运营支撑系统电信运营图的服务等级协定及服务等级协定的管理框架。 相似文献
22.
短信市场巨额收入的刺激,再加上市场监管力度不够,使得一些服务提供商(SP)片在追求收益而忽视消费者需求,导致短信服务走入了一些误区,这已经引起一系列负面效应,要解决此问题,SP应树立服务理念,根据客户的需求来提供服务内容和服务方式;运营商需改进商业模式,应考虑对SP提供的业务内容和配套服务进行规范,用户要维护自身权益,政府则应加强监管能力。 相似文献
23.
No authorship indicated 《Canadian Metallurgical Quarterly》1988,43(4):241b
Presents the citation, biography, and selected bibliography for Edwin Shneidman, one of the 1987 recipients of the American Psychological Association's Award for Distinguished Professional Contributions to Public Service. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
Service Load Effective Compression Flange Width in Fiber Reinforced Polymer Deck Systems Acting Compositely with Steel Stringers 总被引:1,自引:0,他引:1
This paper reports on the field study of a steel stringer-fiber reinforced polymer (FRP) deck composite bridge in Pennsylvania. The objective of the study is to assess the effective compression flange width in the FRP deck and floor systems when they act compositely with underlying steel girders at service conditions. The research results reported herein support the notion of employing a design approach, for both interior and exterior girders of a composite floor system, that is philosophically consistent with current practice related to steel girders acting compositely with concrete decking. It appears from the results presented herein that FRP decks and floors acting compositely with underlying steel girders exhibit an effective width that is close to the actual girder spacing for interior beams, and approximately one-half this value for exterior beams. 相似文献
25.
26.
Michael Khl Gary Jorgensen Stefan Brunold Bo Carlsson Markus Heck Kenneth Mller 《Solar Energy》2005,79(6):618-623
The economic viability of solar collector systems for domestic hot water (DHW) generation is strongly linked to the cost of such systems. Installation and hardware costs must be reduced by 50% to allow significant market penetration. An attractive approach to cost reduction is to replace glass and metal parts with less expensive, lighter weight polymeric components. Weight reduction decreases the cost of shipping, handling, and installation. The use of polymeric materials also allows the benefits and cost savings associated with well established manufacturing processes, along with savings associated with improved fastening, reduced part count, and overall assembly refinements. A key challenge is to maintain adequate system performance and assure requisite durability for extended lifetimes. Results of preliminary and ongoing screening tests for a large number of candidate polymeric glazing materials are presented. Based on these results, two specific glazings with moderate and poor weathering stability are selected to demonstrate how a service lifetime methodology can be applied to accurately predict the optical performance of these materials during in-service use. A summary is given for data obtained by outdoor exposure and indoor testing of polyvinyl chloride (PVC) and high temperature modified polycarbonate copolymer (coPC) materials, and an initial risk analysis is given for the two materials. Screening tests and analyses for service lifetime prediction are discussed. A methodology that provides a way to derive correlations between degradation experienced by materials exposed to controlled accelerated laboratory exposure conditions and materials exposed to in-service conditions is given, and a validation is presented for the methodology based upon durability test results for PVC and coPC. 相似文献
27.
为了适应MMS(多媒体短信息业务)的发展,提出了一个基于图像扭曲的变形动画生成机制。该机制不仅能够实时地产生效果新奇、富于戏剧性的GIF动画,而且能够根据不同终端的特点实现图像的自适应处理,从而使在无线网络上传输丰富多彩的图像文件变得更为方便。 相似文献
28.
Boiler tubes in power plants have finite life because of prolonged exposure to high temperature, stress and aggressive environment. Service-exposed platen superheater and reheater tubes (148,900 h) made of 2.25Cr-1 Mo steels in a 120 MW boiler of a thermal power plant were evaluated for remnant life. The investigation included hot tensile tests, hardness measurement, dimensional measurement, microscopy and creep tests. Experimentally determined yield and ultimate tensile strength, and estimated 10,000–100,000 h rupture strength in the temperature range 520–580 °C, exhibited a decreasing trend with increasing temperature. Microstructural study did not reveal any significant degradation in terms of creep cavities, cracks, graphitization, etc. Analysis of tensile and stress rupture data revealed that although there was degradation of the tubes due to prolonged service exposure in terms of the ultimate tensile strength values, stress rupture plots showed that the service exposed superheater and reheater tubes could remain in service for a length of more than 10 years at the operating hoop stress of 40 MPa/540 °C, provided no localised damage in the form of cracks or dents develop. 相似文献
29.
Domenico Ferrari 《Multimedia Systems》1998,6(3):179-185
The research done by the Tenet Group in multimedia networking has reached a point where it may be useful to reflect on the
significance of its results for the current debate on how integrated-services internetworks should be designed. Such reflections
constitute the main subject of this paper. The principles of the work and the conclusions reached so far by the Tenet researchers
are discussed in the light of the conflict between the two major technologies being proposed to build future information infrastructures:
namely, the Internet and the ATM technologies. The Tenet approach suggests one feasible way for resolving the conflict to
the advantage of all the users of those infrastructures. This paper discusses various fundamental aspects of integrated-services
network design: the choice of the service model, the type of charging policy to be adopted, and the selection of a suitable
architecture. 相似文献
30.
王茜 《数码设计:surface》2012,(5):104-106
公益产品设计近年来备受社会瞩目,其构想的价值毋庸置疑,然而,在设计中,一些思想未必成熟,各方面因素考虑不周,设计出的产品不仅难以实现公益,甚至出现南辕北辙的无奈。把握公益产品设计的正确方向,使得产品设计能够真正做到公益的效果,对于参与公益产品设计的企业和设计者而言是当务之急。 相似文献