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81.
以牛头山水电厂为研究对象,提出中小型水电厂黑启动方案,以最快的速度实现水电厂自救及向电网送电,恢复电网安全运行.通过试验比较,结合牛头山水电厂实际运行方式,制定有效的牛头山电厂黑启动方案. 相似文献
82.
从德州学院专业建设的实践出发,探讨地方高校转型背景下,人文地理与城乡规划专业应用型人才培养方案构建的思路、培养目标的定位、课程体系的设计等问题,为地方本科院校专业建设提供参考。 相似文献
83.
This paper quantitatively measures technological change in U.S. jet fighter aircraft from 1944 to the present day using the hedonic pricing approach. The technical and performance characteristics of jet fighters have changed dramatically between the time they were first developed at the beginning of the 1940s and the present. Parallel to this technological change there has been a sharp escalation in costs regarding the new generations of jet fighter aircraft. We estimate a measure of price for the performance and technical characteristics of these aircraft. Embodied technological change in jet fighter airframes is measured using quality-adjusted prices. Although the flyaway cost of jet fighter aircraft has soared, on average, by about 12.63% per year, the quality-adjusted aircraft cost has only risen by about 2.6% per year, a figure lower than the average observed general inflation rate for the period (around 4%). This represents an impressive average technological progress ratio of around 10% per year. A revealed preferences argument shows that the characteristic most valued by the government is stealth capability, followed by advanced avionics. 相似文献
84.
Emergence of new industries from evolving technologies is critical to the global economy, yet has been relatively understudied due to the paucity of available data. This study draws lessons on industry emergence, by analyzing how a solid-state lighting (SSL) industry grew out of light emitting diode (LED) technologies that evolved for half a century, with participation by tens of thousands of researchers in universities, national laboratories, and firms. Using data on publications, patents, and firms combined with business history we trace the evolution of SSL through a succession of market niches. At times a few researchers with unorthodox research approaches made breakthroughs that greatly advanced particular technology trajectories and pushed LED research in unexpected directions. A succession of LED market niches advanced the technology and provided profits to incentivize continuing research while reducing cost and improving efficacy of LEDs. Innovating firms developed a thicket of patents and captured substantial profit, but were embroiled in extensive litigation that was ultimately resolved through cross-licensing. A major new generation of lighting products is now disrupting the traditional lighting industry. Although the leading incumbent lighting firms all invested early and heavily in SSL, the industry's future leadership is uncertain. 相似文献
85.
张莹 《苏州市职业大学学报》2014,(4):90-92
针对高等职业院校单独招生的制造类专业学生开展能力特征分析研究,通过调研及对比分析,得出机械制造类专业、电气制造类专业的不同培养要求、能力特征,为同类专业及相似专业的人才培养提供借鉴参考. 相似文献
86.
革除空泛"说教",提升"说服"力度,成为我国当前和未来园林解说系统发展的必然选择。本文基于技术创新的时代背景以及园林解说系统的发展现状,以南昌天香园为案例实证分析园林解说系统的有效性,并在此基础上,构建园林解说系统的技术创新模式,提出园林解说系统的技术创新策略。 相似文献
87.
针对山西大同某煤矿辅助巷道支护结构的锚杆与锚索的设计,采用理论设计、数值模拟、观测设计、工程类比几种方法的综合设计进行方案选择、设计优化。此方案不仅在经济方面,而且在技术、安全方面都满足要求,对类似的工程起到借鉴的作用。 相似文献
88.
我国高校体育教育专业目前课程方案实施状况的调查研究 总被引:4,自引:1,他引:4
运用调查分析和专家咨询法,对我国部分高校体育教育专业现行课程方案进行了调查和比较分析结了他们的基本特征,提出了进一步改革所需要认真探讨的问题。 相似文献
89.
Business cycles modify firms’ incentives to innovate and the direction of innovation. By introducing a new measure of patent unconventionality this paper explores the impact of the business cycle on firms’ technological search strategies. We find that during upturns firms generate inventions characterized by a higher level of technological unconventionality. We also find that financially resilient and diversified firms produce more unconventional patents. While patent unconventionality is associated with technological impact and market value, firms extract more value by investing in unconventional inventions in downturns. 相似文献
90.
粘钢技术因施工工艺简便、效率高、成本低和效果明显等优点而被广泛应用于房屋建筑及桥梁工程加固。本文通过框架梁加固的运用实例,分析粘钢技术的加固方案、构造及施工要求。 相似文献