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141.
钱卉 《杭州电子科技大学学报》2004,24(2):23-25
科学知识社会学是目前科学社会学研究中相对独立的研究领域,它的产生有着深刻的哲学和历史背景,科学知识社会学在研究方法和研究内容上都脱离了传统的科学社会学,着重对科学知识本身进行考察。 相似文献
142.
首先对呼图壁气藏的凝析气高压PVT实验数据进行拟合计算,确定了适合该气藏流体相态行为的流体组分特征参数;利用地质研究成果所确定的单井各层物性参数,结合构造形态和井位,建立了相应的三维地质模型;在完成了储量拟合以后,针对气藏生产历史数据进行历史拟合研究,取得了令人满意的拟合效果;为了研究呼图壁气藏未来的开发动态,从9个方面对该气藏的开发指标进行了数值模拟对比研究,所得的研究结论有利于指导该气藏实际开发生产. 相似文献
143.
Usually many researchers have used the modified Hertzian contact law or experimental static indentation law to analyze impact response of composite laminates subjected to low-velocity impact. In this study, physical meaning of the analytical method using the laws was investigated and the difference between the analytical results obtained using the two laws was also investigated. Furthermore parametric study on contact coefficient and exponent of the contact law was performed. Finally it could be shown that linearized contact law could be well applied to the low-velocity impact analysis of composite laminates. If this concept is used, any general-purpose finite element method software can be used to solve impact problem without direct developing any FEM code by each researcher. In this paper, some analytical results analyzed using a general-purpose commercial FEM software were also presented. 相似文献
144.
Presents reflections on the life and achievements of Josef Maria Bro?ek. The author notes that, in his way, Bro?ek turned psychology historiography into an international domain involving, in this construction, researchers from countries not only of Anglo Saxon languages but also those of Slavic and Latin languages, including Brazil. Quoting from Braque, he affirmed that "knowledge of the past enables the revelation of the present." However, he believed that "reality is not revealed if it is not sparkled by a poetic beam." The poetry of life illuminated Bro?ek and his actions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
145.
Kalman David; Kahler Christopher W.; Tirch Dennis; Kaschub Cynthia; Penk Walter; Monti Peter M. 《Canadian Metallurgical Quarterly》2004,18(1):78
This study reports findings from an investigation of the efficacy of high-dose nicotine patch (NP) therapy for heavy smokers with a past history of alcohol dependence. One hundred thirty participants were randomly assigned to 42 mg or 21 mg of transdermal nicotine for 4 weeks, followed by an 8-week dose titration. Follow-up assessments were conducted at 4 and 12 weeks. Differences between dose conditions were nonsignificant, although unexpectedly, outcomes favored participants in the 21-mg NP condition. Nicotine abstinence at follow-up was related to longer length of alcohol abstinence at time of enrollment. Future research should investigate ways to improve smoking quit rates in this population, including more frequent counseling sessions and/or other pharmacotherapies. These investigations should focus primarily on smokers in early alcohol recovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
146.
Comments on the article by Sanchez and Turner (see record 2003-03405-005) examining the implications for practice and training in psychology in the era of managed care. The current author states that Sanchez and Turner should be commended. Their article amplifies and clarifies critical issues psychologists must consider while practicing within an era increasingly shaped by health insurance policies and practices. Nevertheless, the author feels that several intriguing facets of managed care were not highlighted. Discussion focuses on the impact that reimbursement and managed care is having on school (and clinical) psychologists. The author points out that it is unknown to what extent managed care may (and has) altered psychological services delivered by school psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
147.
THEORETICAL ANALYSIS AND EXPERIMENTAL VERIFICATION ON TERNARY-WAVES METHOD TO COMPILE ACCELERATED SPECTRA 总被引:1,自引:0,他引:1
Xiong Junjiang Wu Zhe Gao ZhentongAircraft Design Bureau Beijing University of Aeronautics Astronautics Beijing China 《机械工程学报(英文版)》2002,15(4):308-313
The equivalent damage calculation formulae of fatigue crack formation and growth are established. In order tocompile the fatigue crack formation and growth accelerated load spectra, the main wave shapes and load sequence of theactual load spectrum are kept constant, and the carrier waves are cut off. And secondary waves are put together into newsecondary waves to shorten the test time according to the equivalent damage calculation formulae respectively. Then bythe fatigue cumulative damage calculation of the fatigue crack formation and growth accelerated load spectra, the onecorresponding to the bigger damage is determined as the fatigue accelerated test load spectrum. Therefore in the test process, the fatigue accelerated test spectrum may be applied till fatigue failure, the engineering fatigue crack length of full-scale structure need not be inspected, and the fatigue crack formation accelerated load spectrum need not be transferredinto the fatigue crack growth accelerated load spectrum. Finally, it 相似文献
148.
针对特征提取和故障识别这两个轴承故障诊断的关键环节,提出一种汽车电机轴承故障诊断新方法。该方法在特征提取环节:提出了将LCD分解和符号熵(SE)相结合的特征提取方法;在故障识别环节为提高果蝇算法(FOA)对相关向量机(RVM)参数的寻优能力,在FOA算法中增加了向"历史"学习的策略,提出具有历史学习能力的果蝇算法(HSAFOA),有效地提升了RVM的分类性能。汽车电机轴承不同类型、不同程度故障诊断实例表明,LCD符号熵可有效对故障进行表征,而HSAFOA算法则提升了RVM的识别效果,相比于其他一些方法更有优势。 相似文献
149.
150.
During the colonial times, electricity in India developed for a significant part thanks to British investment. Its growth remained modest and mainly linked to industrial needs, public lighting and common transportation. World War II stimulated industrial production and, consequently, the demand for electricity. The immediate years following the war were even more promising since the preparations for national Independence included a major restructuring of electricity generation and distribution. The 1948 Law on electricity and the first 5-year plans which began in 1951 set the framework for a major development. Instead of nationalization, India chose a policy which allowed for the participation of both private and public enterprises. British and Indian private investment responded positively to the change. At the beginning of the 1950s, the British presence was felt in the power industry. However, a decade later, it was already diminishing. This paper explains the nature of the policy which allowed a partnership between private and public sectors, the reasons why the latter finally prevailed over the former and the consequences on British investment. 相似文献