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91.
介绍了某型导弹发控盒电路板综合测试系统的硬件和软件设计,该系统以PC计算机为平台,采用总线式设计思想,实现了对电路板检测的自动化、快速化和智能化.  相似文献   
92.
汽车已经成为现代物质文明的一种象征和人类生活中不可缺少的部分,而汽车在一个国家的普及程度,也成为衡量其工业化的重要标志.本文论述了国内外汽车产品发展状况和汽车产品的开发体系.  相似文献   
93.
Medication adherence—taking medication as prescribed—is critical for successful self-care, especially among older adults. Adherence depends on developing and implementing plans for taking medications. Age-related cognitive declines that affect adherence may be mitigated using external tools that support patient-provider collaboration needed to develop these adherence plans. We tested the effectiveness of structured collaborative medication tools to support better medication planning and adherence practices. Evidence for benefits of collaborative tools has been mixed in terms of their usefulness for medication-scheduling tasks, perhaps because the tools have not been explicitly designed to support patient-provider collaboration. A total of 144 community-dwelling older adults participated in pairs and performed the role of a patient or provider in a simulated patient-provider medication-scheduling task. Each pair worked with a structured (MedTable? and e-MedTable) or unstructured (Medcard) scheduling tool and completed four problems (2 simple and 2 complex). Performance was measured using the following: problem-solving (medication schedule) accuracy, problem-solving time, solution (schedule) optimality, tool usability, collaborative effectiveness, and subjective workload involved in creating the medication schedules. Participants using structured tools produced more accurate and optimal schedules. They also rated subjective workload as lower and thought that the structured tools were easier to use, reduced subjective workload associated with creating the schedules. There was also suggestive evidence that participants using the structured tools rated more highly the quality of their collaboration. Structured medication-scheduling tools have the potential to improve medication adherence among older adults because they support collaborative planning and reduce the cognitive load involved in creating these adherence plans.  相似文献   
94.
男同性恋群体的城市空间分布及文化生产:以沈阳为例   总被引:3,自引:0,他引:3  
富晓星  吴振 《工程研究》2010,2(1):38-52
From the pespective of space-culture, this paper explores how gay people's body, behavior and social relations are organized, represented and understood in Shenyang city by adopting participating observation, in-depth individual interview and historical literature review. Through the interaction between the urban space and the gay groups' inner characteristics, this paper finds out that the urban space constructs a dynamic platform for the mobilization of homosexual behavior, emotion and identity.  相似文献   
95.
The InAlAs/InGaAs metal-oxide-semiconductor metamorphic high electron mobility transistors (MOS-mHEMTs) were demonstrated by using liquid-phase HBr treatment technology to form a high-quality gate insulator layer. In this study, liquid-phase HBr treatment technology was used instead of traditional plasma-assisted chemical vapor deposition (PECVD) because the proposed technology can prevent the device from plasma-induced damage. The novel HBr + ultraviolet (UV) illumination treated InGaAs provided a lower surface states such that MOS structure can be efficiently obtained. Besides, based on the atomic force microscopy (AFM) measurement, the native oxides film formed by HBr + UV illumination treatment also provided a better surface roughness compared to traditional NH4OH and only HBr treatment solutions. It is beneficial for reducing the surface traps and lowering the leakage current in MOS-mHEMTs. Based on the flicker noise and load-pull power measurement results, HBr + UV treatment mHEMT achieved a low flicker noise at high current level and the power-added efficiency can be enhanced up to 9%. Therefore, the novel liquid phase method of HBr + UV illumination treatment exhibited a highly potential for low noise microwave power device applications.  相似文献   
96.
In 100% inspection, measurement errors are unavoidable. Due to these errors, acceptable products are sometimes rejected (overkill) and defective products are accepted (escape). Overkill increases production costs, while escape is a source of customer dissatisfaction. This study presents a model for calculating overkill and escape rates using process and measurement system performance data. A practical example of applying the model is also presented to calculate gage reproducibility and repeatability requirements for different production settings. Industrial managers and quality engineers can utilize the results of this study to calculate escape and overkill rates of their production systems, and to assess and improve their processes.  相似文献   
97.
应用型本科院校担负着为地方以及周边地区培养具有生产、经营、管理、教学等知识和技能的专门性人才的艰巨任务,非英语专业大学英语课程是应用型本科院校开设的一门必修课程和公共性课程.无论在规模上还是在权重上,大学英语课程都占据极其重要的地位.从学力理论的发展性学力视角探究该课程的承载者,无论对教学对象本身、英语教师的教学以及教学管理来说都具有极其重要的参考价值.  相似文献   
98.
A new statistical micromechanical model of multiple cracking is proposed in which a general expression of the fiber bridging stress laws in the crack plane is established. In this model, the random distribution properties of fibers are considered. And the Weibull function is adopted to represent the flaw size distribution. The relationships of stress versus strain and crack width versus strain are proposed. The formulas of the crack width, crack space, strain capacity and fracture energy density at the end of multiple cracking processes are also deduced. The validity of the proposed model was demonstrated by experimental results.  相似文献   
99.
Hydrogenated nanoamorphous Si (na-Si:H) films have been fabricated by reactive pulsed laser ablation technique with hydrogen as reactive gas. It is found that the hydrogen pressure has a great effect on both the structure and photoluminescence (PL) properties of the films. Increasing the hydrogen pressure leads to a structural transition of the films from amphorous Si to na-Si:H, and the PL center wavelength of the na-Si:H films is varied with the hydrogen pressure. The PL decay times of the na-Si:H films are in the nanosecond scale and are shorter on the high energy side of their PL spectrum. The results demonstrate that the na-Si:H films are promising candidates for visible, tunable and high-performance light-emitting devices.  相似文献   
100.
The relationship between the embedding depth and the residual stress in the brazed cBN grains is analyzed experimentally in order to optimize the embedding depth of grains in the monolayer brazed abrasive tools. It is found that the residual stress is stable without remarkable gradient in the core zones of the brazed grains. However, the stress distribution gradient is rather great in the regions such as both ends of the central axis, the margin region of the central plane in the cBN grains, and the margin region of the section plane between the grains and the filler top. The maximum tensile stress in the margin zone of the brazed cBN grains has the most important influence on the mechanical property of the grains. The embedding depth is accordingly optimized at 30-40% of the total height of cBN grain.  相似文献   
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