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91.
吴立新 《石油沥青》2002,16(1):46-51
以灌溉、防洪为主的峡口水库大坝,为沥青混凝土面板堆石坝,为研究低温抗裂性能,对沥青混凝土面板破损取样,进行了配比和多种力学性能试验,并与原面板设计指标进行了对比。由于面板经受住了-20℃以下的低温考验,其所用沥青指标、破损取样试验结果,特别是冻断低温指标,对确定水工沥青混凝土低温抗裂检验标准有重要参考价值。  相似文献   
92.
毛洪涛 《电子质量》2002,(11):57-59
本文讨论了电磁兼容对电视机的技术要求和相应对策。  相似文献   
93.
This paper introduces a new concept of testability called consecutive testability and proposes a design-for-testability method for making a given SoC consecutively testable based on integer linear programming problem. For a consecutively testable SoC, testing can be performed as follows. Test patterns of a core are propagated to the core inputs from test pattern sources (implemented either off-chip or on-chip) consecutively at the speed of system clock. Similarly the test responses are propagated to test response sinks (implemented either off-chip or on-chip) from the core outputs consecutively at the speed of system clock. The propagation of test patterns and responses is achieved by using interconnects and consecutive transparency properties of surrounding cores. All interconnects can be tested in a similar fashion. Therefore, it is possible to test not only logic faults but also timing faults that require consecutive application of test patterns at the speed of system clock since the consecutively testable SoC can achieve consecutive application of any test sequence at the speed of system clock.  相似文献   
94.
As System on a Chip (SoC) testing faces new challenges, some new test architectures must be developed. This paper describes a Test Access Mechanism (TAM) named CAS-BUS that solves some of the new problems the test industry has to deal with. This TAM is scalable, flexible and dynamically reconfigurable. The CAS-BUS architecture is compatible with the IEEE P1500 standard proposal in its current state of development, and is controlled by Boundary Scan features.This basic CAS-BUS architecture has been extended with two independent variants. The first extension has been designed in order to manage SoC made up with both wrapped cores and non wrapped cores with Boundray Scan features. The second deals with a test pin expansion method in order to solve the I/O bandwidth problem. The proposed solution is based on a new compression/decompression mechanism which provides significant results in case of non correlated test patterns processing. This solution avoids TAM performance degradation.These test architectures are based on the CAS-BUS TAM and allow trade-offs to optimize both test time and area overhead. A tool-box environment is provided, in order to automatically generate the needed component to build the chosen SoC test architecture.  相似文献   
95.
The guide-pieces, used in the process line of steel rolling, were the important components. The guidepieces, which were slide contacting with the rolled-piece, had a high temperature and high speed. The wear was very serious. The results from failure analysis showed that there were three failure forms in the guide-pieces: the first was the wear during heat friction, the second was the heat fatigue under the cycle of deep heating and deep cooling, and the third was the impact rupture. Among them, the wear was the main reason. To the wear of guidepieces, there were four mechanisms, namely abrasive wear, adhesive wear, fatigue wear and corrosion wear. The failure analysis to the guide-piece laid the foundation for its remanufacturing. Foundation item: Project(50235030) supported by the National Natural Science Foundation of China  相似文献   
96.
One of the new physical methods that provides much information about the processes going on in a friction contact zone in real time is acoustic emission (AE). Basic experimental results of AE in friction are presented and analysed. Using AE signals we can get an indication about the state of the friction processes, about the quality of solid and liquid layers on the contacting surfaces in real time, sometimes about intensity of wear, changing of wear and friction regimes and so on. The influence of sliding velocity, load, roughness and some physical and mechanical properties of the body on the parameters of AE are also given. Some attention to the practical implementation of these techniques for control of capability for work of friction pairs in real conditions are given. Modern methods and devices enable condition monitoring of sliding and rolling bearings.  相似文献   
97.
介绍气体加速泵的结构、工艺原理及现场试验情况.通过室内实验和研究,并在蜀南气矿S1、S2井进行了先导性试验,对其在有水气田的应用作出了适应性评价.  相似文献   
98.
What is the current standard of practice for evaluations of juvenile competence to stand trial (JCST)? The present study surveyed psychologists regarding the practices used when conducting JCST evaluations. Respondents rated the importance of 17 elements that might be included in a JCST evaluation report. Of these elements, 7 were considered essential by 70% or more of respondents, with 9 additional elements rated as either essential or recommended. A majority of respondents felt that the use of psychological and forensic instruments was important. A list of tests used is provided, and the implications for the development of standards and policy are discussed to provide practitioners with additional knowledge that will help to further the state of the discipline. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
通过广泛分析国内外对土壤源热泵实验研究的现状,建立了可以模拟多个地区、多种运行工况的土壤源热泵沙箱实验台,并进行了绝热边界工况短期内取热的实验研究。  相似文献   
100.
Abstract. We analyze, by simulation, the finite‐sample properties of goodness‐of‐fit tests based on residual autocorrelation coefficients (simple and partial) obtained using different estimators frequently used in the analysis of autoregressive moving‐average time‐series models. The estimators considered are unconditional least squares, maximum likelihood and conditional least squares. The results suggest that although the tests based on these estimators are asymptotically equivalent for particular models and parameter values, their sampling properties for samples of the size commonly found in economic applications can differ substantially, because of differences in both finite‐sample estimation efficiencies and residual regeneration methods.  相似文献   
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