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101.
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   
102.
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   
103.
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   
104.
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   
105.
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   
106.
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   
107.
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   
108.
基于函数映射的FFT谐波分析的研究   总被引:1,自引:0,他引:1  
因为免除了等待和倒序操作,从而使递推实现的FFT在谐波分析中更具有实时性,已呈现出取代常规FFT的趋势。本介绍了一种递推实现的FFT算法——基于函数映射的FFT算法的原理和程序过程,进行了其应用于谐波分析的全面性能评估。通过与基于离散Hartely变换的谐波分析的性能的比较,发现尽管两的系统误差相同,但它的频谱噪声底线稍低于后,频谱泄漏优于后,且更易于硬件实现。  相似文献   
109.
采用潮流跟踪法的输电费分摊算法   总被引:7,自引:0,他引:7  
研究了在复杂电网内分摊输电线路的固定成本的方法。输电费分摊常用的方法有邮票法和MW—km法,前者较简单但没有考虑输电距离,不够公平;后者既考虑输送距离又考虑输送功率的大小,比较合理,但在复杂电网内分摊实现较困难。文中用一个5节点算例对潮流跟踪算法和直流灵敏度系数法进行了比较,结果证明前者物理概念清晰而且与平衡机节点位置的选择无关,所以推荐采用潮流跟踪法计算输电费的分摊。  相似文献   
110.
一种基于傅里叶描述子的轴心轨迹自动识别方法   总被引:6,自引:0,他引:6  
傅里叶描述子是分析和识别物体形状的重要方法之一。文中详细讨论了傅里叶描述子的原理、不变性和实际应用方法;运用人工神经网络分析方法,以傅里叶描述子作为特征向量,对汽轮发电机组轴心轨迹的自动识别进行了探讨;并对3类典型的轴心轨迹的自动识别进行了仿真试验,结果表明该方法是有效、可行的。  相似文献   
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