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151.
王兆芳 《山西建筑》2010,36(28):208-209
以学院学术报告厅观众看台工程为例,对物资,施工方案,施工工艺,成品保护等方面具体阐述了折线形预应力梁施工质量保证措施,从而在施工过程中严把质量关,做到全面质量控制。  相似文献   
152.
Thin polymer films are deposited on nonplanar geometries via initiated chemical vapor deposition (iCVD). Films in microtrenches exhibit step coverage of 0.85 for the highest aspect ratio trench studied here. An analytical model shows that the sticking probability of the initiating radical is a function of monomer surface concentration and takes values between 1.1 × 10− 2 and 5.0 × 10− 2 for the conditions studied here. These results indicate that iCVD proceeds via reaction of a vapor phase initiating radical with a surface adsorbed monomer. The high degree of conformality allows iCVD to be used to create patterns with features less than 10 µm by physically masking the substrate.  相似文献   
153.
This paper proposes an olfaction based methodology to automatically cover an unknown area enabling the decoupled cooperation of a group of floor cleaning mobile robots. This method is based on the utilisation of low cost chemical sensors in cleaning mobile robots, in order to differentiate clean from dirty areas. The experimental results show that the use of olfactory capabilities allows to efficiently cover and clean a certain area, and demonstrate the possibility of coordinating several mobile robots without the need of expensive sensing capabilities, map building or complex algorithms for task scheduling.  相似文献   
154.
结合实际的移动adhoc组网研究,针对以往MANET路由协议性能评价中没有考虑网络连通性的问题,引入了反映网络节点通信能力和网络连通性的网络覆盖密度概念,并进行了基于拓扑的MANET典型路由协议性能与网络覆盖密度相关性的研究.仿真结果分析表明,基于拓扑的adhoc路由协议包递送率随着网络密度的增加而增加,并与其构成S曲线.通过最低网络覆盖密度的定义,为实际的adhoc组网中各种路由协议的适用条件提供了明确的评判依据.  相似文献   
155.
自动基站分布问题属于组合优化中的NP完备问题,为此针对3G网络规划,在遗传算法的基础上,采用DCMOGADES算法的思想提出了一种新的自动基站分布算法。算法以容量、覆盖和成本作为目标,采用基站位置、天线高度和发射功率的三维向量编码方式,考虑了实际问题中的业务密度区域问题,对DCMOGADES算法进行改进并做出仿真。仿真结果表明,该算法能快速找到Pareto最优解。  相似文献   
156.
This paper proposes a set of new software test-diversity measures based on control oscillations of test suites. Oscillation Diversity uses conversion, inversion, and phase transformation to vary test suite amplitudes, frequencies, and phases. Resistance and inductance are defined as measures of diversification difficulty. The experimental results show correlation between some Oscillation Diversity measures and fault-detection effectiveness.  相似文献   
157.
The role of psychologists as health care providers and the parameters of reimbursement for health care services are timely and controversial issues. A landmark decision was reached in this controversy in the 1980 appeal of a Virginia suit by clinical psychologists in which the court ruled that Blue Shield's refusal to directly reimburse psychologists was a violation of antitrust law. Thus, the requirement that psychologists bill through physicians was not upheld. In recent years a specific aspect of this controversy involved psychologists' roles in potential national health insurance programs. A limited study (appearing in the "National Register of Health Services Providers in Psychology" 1976-1978) of clinical psychologists' attitudes toward national health insurance suggests that Congress and psychologists may have disparate views. In addition to favoring national health insurance, over 85% of psychologists surveyed responded that consumers would benefit from such a program with mental health coverage. Only 16% agreed that such a program would constitute a subsidy of the rich by the poor (Albee, 1977). Several areas of conflicting or confusing responses in this study may reflect legitimate reasons for concern by Congress regarding institution of national health insurance. Belief that providers would benefit from mental health coverage in a national health insurance program was shared by 80% of respondents. Ninety-five percent of respondents identified the inclusion or exclusion of clinical psychologists in such a national health insurance as affecting the future of the profession. Curiously, over 50% of respondents agreed that primary care physicians should be reimbursed for mental health services, although such physicians have received no formal training in psychological services. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
158.
159.
We introduce SImulation Verification with Augmentation (SIVA), a tool for coverage-directed state space search on digital hardware designs. SIVA tightly integrates simulation with symbolic techniques for efficient state space search. Specifically, the core algorithm uses a combination of ATPG and BDDs to generate directed input vectors, i.e., inputs which cover behavior not excited by simulation. We also present approaches to automatically generate lighthouses that guide the search towards hard-to-reach coverage goals. Experiments demonstrate that our approach is capable of achieving significantly greater coverage than either simulation or symbolic techniques in isolation.  相似文献   
160.
Detection coverage control is one of the most important topics in the intrusion detection problem of wireless sensor networks (WSN). However, its converse, i.e., to design an object locomotion trajectory in WSN, has not received enough attention. This article proposes a heuristic algorithm, namely, the security & speed (SS) algorithm, to depict such a trajectory that takes into consideration both security and speed. The merit of the SS algorithm is its topology independency. When compared with traditional algorithms, the SS algorithm approaches the optimal trajectory better, and enjoys considerably lower computational load, and a better and adjustable tradeoff between trajectory security and speed.  相似文献   
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