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铁电斯特林制冷机的生态学优化性能 总被引：1，自引：0，他引：1
应用有限时间热力学理论，研究热阻及回热损失对铁电斯特林制冷机生态学优化性能的影响，所得结论可为铁电斯特林制冷机的研制和设计提供参考。 相似文献
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研究了受热阻、热漏和回热损失影响的不可逆斯特林制冷机制冷率和制冷系数的最高和最低界限。为斯特林制冷机工作参数的选择提供了两条有限时间热力学新准则。 相似文献
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复杂文本布局引擎机制及应用研究 总被引：4，自引：0，他引：4
目前应用较为广泛的复杂文本布局引擎有微软的Uniscribe和IBM的ICU。通过对复杂文本布局引擎机制的研究，结合开放源码的复杂文本布局引擎（如ICU布局引擎）代码分析，我们可以在其中加入该引擎尚未支持的复杂文本（如我国少数民族语言蒙、藏、维）的实现模块，并以此开发出基于OpenOffice的用于我国少数民族地区的办公套件。本文先介绍什么是复杂文字和复杂文本，接着阐明复杂文本布局引擎机制，最后讲解了复杂文本布局引擎ICU及其在开发基于OpenOffice的我国少数民族办公套件中的应用。 相似文献
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The purpose of this study is to provide automatic new topic identification of search engine query logs, and estimate the effect of statistical characteristics of search engine queries on new topic identification. By applying multiple linear regression and multi-factor ANOVA on a sample data log from the Excite search engine, we demonstrated that the statistical characteristics of Web search queries, such as time interval, search pattern and position of a query in a user session, are effective on shifting to a new topic. Multiple linear regression is also a successful tool for estimating topic shifts and continuations. The findings of this study provide statistical proof for the relationship between the non-semantic characteristics of Web search queries and the occurrence of topic shifts and continuations. 相似文献
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随着科学研究的深入发展,人们对文献需求越来越广泛,对搜索引擎理论的研究正在朝着多元化、专业化方向发展。特别是新型文献载体的出现,开阔了搜索引擎理论研究的新视野。本文从搜索引擎的组成,搜索引擎的分类,如何识别搜索引擎的优劣,搜索引擎的未来发展动向等方面对搜索引擎技术做介绍。 相似文献
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从理论分析了摩托车发动机研制与开发可行性,提出了新型发动机主要结构上的设计要点,简单介绍了发动机研制开发的成功经验,高新技术的综合应用,是提高摩托车质量性能的有效途径. 相似文献
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本文论述了搜索引擎的概念、基本原理、主要功能及作用,并针对国内比较著名的搜索引擎站点进行了详尽的分析,在此基础上,对中文网络搜索引擎发展的现状进行了分析,在看到中文搜索引擎发展的同时,也要看到中文搜索引擎在发展中存在的问题。 相似文献
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[目的/意义]创新生态系统是近年兴起的热门领域,反映了学术研究前沿与趋势。对其学科多样性进行研究有助于激发学术思想碰撞,产生新见解,为科技政策制定与管理提供依据。[方法/过程]基于共类分析,以Web of Science数据库创新生态系统领域2002-2017年相关核心文献为目标,通过学科覆盖图,学科丰富度、均匀性、差异性和综合测度指标对比分析创新生态系统领域学科多样性特征。[结果/结论]创新生态系统领域整体学科多样性较强,主要集中于邻近领域或学科。且创新生态系统受其他领域的影响大于其本身对其他学科的影响。时序上,其学科多样性并无显著增强趋势,但总体上目标文献被引频率越高,学科多样性越强。 相似文献
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D.C. Gazis 《Research Policy》1979,8(3):244-259
The stimulation of technological development by scientific discovery is a widely accepted premise. Somewhat less recognized is the inverse relationship, the stimulation of science by technology. Examples of the latter are the advances in thermodynamics following the development of the steam engine by Watt; and the advancement of the understanding of thermionic emission into gases, by Langmuir, following his own invention of the nitrogen-filled electric bulb.In this paper, we discuss several examples of contributions to science at IBM Research which were generated by our technological effort. These are of two types. The first one comprises scientific investigation stimulated by the need to understand some technological problems. Examples are the ‘two-dimensional electron gas’ investigations inspired by the desire to understand the physical properties of the planar field-effect transistors; or contributions to the theory of magnetism stimulated by the advent of ‘magnetic bubbles’ as a promising storage medium. The second type of stimulation of science by technology is the creation of new tools for scientific investigation. Examples are advances in electron-beam microscopy, originating from a search for improved microfabrication techniques; or the development of tunable lasers, coming out of a search for new devices, not necessarily with a computer orientation, and finding a wide range of applications in physics, chemistry and biology.Beyond enumerating several examples such as the above, we have made an attempt to identify factors contributing to the cross-fertilization of science and technology. We propose three as among the most important ones: strong interactions among scientists and technologists; novelty of the technology involved; and initiative coupled with a searching attitude for underlying principes and phenomena on the part of the researchers involved. 相似文献
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Pak Kin Wong Xiang Hui Gao Ka In Wong Chi Man Vong 《Journal of The Franklin Institute》2018,355(4):1517-1538
Modern engines are controlled by electronic control units, which operate all the engine actuators based on the signals from various sensors in the engine. Traditionally, the control parameters of the actuators are obtained through huge amount of trial-and-error experiments. However, using traditional approach to calibrate these parameters becomes more challenging with the increasing incorporation of new technologies into advanced engines. In order to reduce the number of experiments required in the calibration process of modern engines, a novel point-by-point engine calibration approach based on machine learning methods is proposed in this study. It is an iterative procedure that, for a given operating point, sequential design of experiment (DoE) strategy is utilized to measure the responses of different engine sensors corresponding to different actuator signals, and a machine learning algorithm called initial-training-free online extreme learning machine is utilized to incrementally learn the relationship between the sensors and actuators based on the measurement acquired. In each iterative cycle, meta-heuristic optimization is performed on the machine-learning-based model to search for the best parameters, which are then used as the initial parameters for generating DoE plan of the next cycle. The iteration is repeated until the optimal parameters of that operating point are found. To verify the effectiveness of the proposed approach, experiments on both simulation engine in commercial software and real engine in test bench have been conducted. The results show that the engine calibration can be carried out with significant fewer experiments and time by using the proposed approach. 相似文献
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基于RSS技术的个性化信息服务新方式--由雅虎看RSS在搜索引擎中的应用 总被引：12，自引：2，他引：12
雅虎公司于2004年2月推出了自主开发的新一代搜索引擎,其中最令人瞩目的是其MyYahoo!个性化信息服务方式,这种新服务方式基于RSS技术。本文将通过对雅虎的MyYahoo!项目的实证研究,探讨这种技术在搜索引擎中的应用原理。 相似文献
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Knight DM 《Endeavour》2000,24(4):165-169
Humphry Davy (1778–1829) was one of the first professional scientists, earning his living and rising spectacularly from an impoverished upbringing in Cornwall to be President of the Royal Society and a baronet. He owed his rise to patronage as well as to his range of abilities: as a lecturer, as a chemical theorist and as a very early applied scientist. But his exalted position brought him little happiness, for he could not satisfy all the hopes put upon him as the successor to Sir Joseph Banks. Admired rather than loved, he became unpopular and was seen as haughty. In his last two years, spent wandering lonely and sickly in Italy and the Alps, he sought to make sense of his life, writing dialogues as his bequest to the new generation. 相似文献
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高新技术产业是湖南新型工业化的强大引擎,湖南新型工业化的推进依赖于高新技术产业的拉动,发展高新技术产业是湖南推进新型工业化的重要着力点.通过分析湖南高新技术产业滞后新型工业化进程的现状,明确了湖南高新技术产业今后的发展思路在于确立高新技术产业的发展重心,加强高科技园区建设,促进产学研结合. 相似文献
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元搜索引擎的虚拟资源分类 总被引：2，自引：0，他引：2
元搜索引擎的虚拟资源分类基于独立搜索引擎数据库的逻辑集成 ,能够增加新的检索途径 ,在一定程度上实现高级检索功能。但其分类体系的构建应综合独立搜索引擎的类目表 ,因此其虚拟资源分类的关键在于如何建立类目组库。 相似文献
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产品类查新的常见问题与应对法则 总被引：3，自引：0，他引：3
陈淑婷 《科技成果管理与研究》2009,(1):33-35
根据多年的查新经验,对不具新颖性的产品、创新性强的产品、通用型产品的新款、更新速度快的电子产品的查新工作,以及如何检索产品的性能指标、外观、结构或图形,如何克服搜索引擎缺陷分别进行了讨论,最后推荐介绍了Thomson公司的新产品发布平台。 相似文献
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Gliboff S 《Endeavour》2005,29(4):162-167
Paul Kammerer's career ended in scandal in 1926 over tampering with his evidence for "Lamarckian" evolution--the infamous midwife toad. But although Kammerer's conclusions proved false, his evidence was probably genuine. In any case his arguments were not simply for Lamarckism and against Darwinism, as the theories are understood today. If we look beyond the scandal, the Kammerer story shows us a great deal about early 20th-century biology: the range of new ideas about heredity and variation, competing theories of biological and cultural evolution and their applications in eugenics, new kinds of laboratories and professional roles for biologists, and changing standards for documenting experimental results. 相似文献