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1.
表面n沟CCD的电离辐射损伤   总被引:1,自引:0,他引:1  
本文报道了150光敏元表面n沟CCD(电荷耦合器件)在不同能量电子和γ射线辐照后的电离辐射效应。试验结果表明,转移失效率在≤10Gy时已明显增大。但大多数器件在累积剂量≤50Gy时,通过调整“胖零”注入仍可工作。在高剂量辐照期间,不同栅偏压器件的转移效率退化存在较大差异。应用高频和准静态C-V技术分析了参数退化的原因。  相似文献   
2.
We consider the quantum optical eight-port homodyne detection scheme in the case that each of the associated photon detectors is assigned with a different quantum efficiency. We give a mathematically rigorous and strictly quantum mechanical proof of the fact that the measured observable (positive operator measure) in the high-amplitude limit is a smearing of the covariant phase space observable related to the ideal measurement, that is, the measurement performed with fully efficient detectors. The result is proved for an arbitary parameter field. Furthermore, we investigate some properties of the measured observable. In particular, we show that detector inefficiencies do not affect the observable's ability to distinguish between different states.  相似文献   
3.
This paper examines the factors determining household adoption of energy efficiency eco-innovations. We do so by testing hypotheses grounded in diffusion and finance theory and the literature on the barriers to energy efficiency. Using two large surveys of UK households, we explore the adoption of nine technologies. Our results indicate ‘investment inefficiency’ amongst household adopters occurs for two reasons. First, contrary to notions of rational choice, we find a negative relationship between the investment return of technologies and their level of diffusion. Second, we show adopters of these technologies display characteristics broadly consistent with diffusion theory, contradicting the prediction of finance theory that investment return, not individual characteristics, should drive adoption. We also find that policy has played a role in inducing the diffusion of these technologies and that tenure and spill-over effects are important in adoption. Finally, adoption is motivated more by a desire to save money than by environmental concern. We conclude by giving examples of how our research can lead to better policy timing and targeting.  相似文献   
4.
The causes and effects of machine breakdowns have frequently been investigated in the past. One popular stream of research studies technical errors in production and analyzes their impact on the inventory policy of the company. In this paper, we show that random shifts in the production rate of a machine, which may occur, for example, due to technical defects, may lead to a reduction in total cost and therewith to an increase in profit. This obvious paradox may lead to situations where it is economically rational for the company to sustain a technically inefficient situation, or even to take measures to intentionally induce a shift in the production rate, for example by damaging the machine on purpose. In this paper, we illustrate this paradox by referring to an existing inventory model, and trace it back to common assumptions made in the literature.  相似文献   
5.
Turkey as a European Union candidate state, signed Kyoto Protocol in 2009, which required reduction in the greenhouse gas emissions. Road freight transportation accounts for a quarter of the emissions from transportation sector, so it is one of the implementation areas for emission reductions. When disaggregate data exist, it is possible to detect inefficiency in freight movements and consequently to quantify emission cost of it in road freight sector. Using roadside axle surveys, this study first described the characteristics of road freight movements in Turkey for the period of 2000–2009. Emission estimations for the same period were presented to form a base for potential emission reduction analyses. The results showed that emission savings could be up to 11% by penalizing empty movements even only in the long haul. However, a policy regarding elimination of only inefficiently loaded movements without targeting reduction of empty runs did not provide significant emission reduction capacity. A scenario of replacing Conventional trucks with Euro IV ones showed significant emission reduction potential, especially for regulated emissions, and it may be the most promising option from application perspective.  相似文献   
6.
通过对石家庄站西广场的售票厅在春运时期的运行状况进行调查,发现其售票服务效率不高,影响旅客的满意度.针对上述问题,提出一种排队论和工业工程相结合的改善方案.该方案结合系统成本、服务效率和旅客需求等因素,利用排队理论分析车站在春运期间的负荷状况,运用工业工程中的模特法对问题实施优化改善,最后借助WinQSB软件对比得到车站在春运期间不同客流量下的合适的服务窗口需求量,并进行了敏感性分析.研究表明,工业工程的应用可以很好地提高售票服务效率、旅客满意度和服务质量,有助于合理规划现有资源,降低车站的运营成本,增强铁路部门的综合实力.  相似文献   
7.
沈海超  胡晓庆 《特种油气藏》2012,19(2):116-119,141,142
针对多数非均质低渗凝析气藏压裂后增产不明显甚至压裂后无效的问题,以某典型非均质低渗凝析气藏为例,对该凝析气藏的压裂设计、施工过程以及压裂后返排情况进行研究及总结,提出非均质凝析气藏压裂前应加强凝析气藏相变特征及储层非均质特征研究、科学选井选层、优化压裂规模、建立反凝析产能伤害评价模型并进行返排速度优选、合理控制生产压差等系列改进措施,以期为提高非均质低渗凝析气藏压裂增产效果提供借鉴。  相似文献   
8.
To examine the role of incomplete blinking in contributing to blink inefficiency, symptoms of dry eye and ocular surface disease. To review methods for diagnosing blink inefficiency (including both reduced overall blink rate and increased incomplete blink rate) and the role of remediation for efficient complete blinking as an essential part of the lacrimal functional unit in maintaining tear homeostasis. Diagnosis and remediation of blink inefficiency appear to have been somewhat misunderstood in the management of dry eye disease. To the extent that a high incomplete blink rate ranks in significance with low blink frequency in contributing to blink inefficiency, measures and remediation of only total blink rate are of reduced usefulness in the diagnosis and treatment of blink inefficiency-related ocular surface exposure, dry eye symptoms and ocular surface disease. In addition, a patient’s blink performance during a biomicroscopy or any other clinical assessment of blink efficiency, is unlikely to be characteristic of or relevant to the blink inefficiency that develops and causes symptoms during their various day-to-day activities. There appears to be a strong case for prescribing blink efficiency exercises in the management of many cases of dry eye symptoms and ocular surface disease. Remediation of spontaneous blink inefficiency may require that a motor memory of voluntary complete, rapid, relaxed and natural looking blink formation is established and maintained as the basis for efficient spontaneous blinking. Voluntary forceful blinking may undermine the motor memory of efficient blinking and risk the depletion of any reserves of lipid.  相似文献   
9.
Android applications are becoming increasingly powerful in recent years. While their functionality is still of paramount importance to users, the energy efficiency of these applications is also gaining more and more attention. Researchers have discovered various types of energy defects in Android applications, which could quickly drain the battery power of mobile devices. Such defects not only cause inconvenience to users, but also frustrate Android developers as diagnosing the energy inefficiency of a software product is a non-trivial task. In this work, we perform a literature review to understand the state of the art of energy inefficiency diagnosis for Android applications. We identified 55 research papers published in recent years and classified existing studies from four different perspectives, including power estimation method, hardware component, types of energy defects, and program analysis approach. We also did a cross-perspective analysis to summarize and compare our studied techniques. We hope that our review can help structure and unify the literature and shed light on future research, as well as drawing developers' attention to build energy-efficient Android applications.  相似文献   
10.
Few studies have considered the quasi‐fixed inputs that have an impact on hospitality. The number of guest rooms and the area of the catering department of international tourist hotels are shown to be constant in Taiwan from 2008 to 2009. Therefore, this paper proposes the use of the two‐stage network directional distance function with quasi‐fixed inputs to explore the productive and service efficiencies of tourist hotel formats (chained versus independent). In addition, a new approach is developed to decompose the technical inefficiency of the hotels within the meta‐frontier; this approach helps to identify the source of the meta‐frontier inefficiency. Demonstration of this new approach with practical data reveals that the average productive efficiency is greater than the average service efficiency for Taiwanese tourist hotels. Additionally, the causes of the overall productive inefficiency and the overall service inefficiency are mainly derived from the input excess of the productive process and the output shortfall of the service process, respectively.  相似文献   
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