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131.
近几年,我国外汇储备逐年增加,而美元汇率偏弱,使我国承担很大的外汇风险。为了规避外汇风险,应增加黄金储备。文中提出了我国增加黄金储备总量的理由以及增加黄金储备的途径。这些建议具有可操作性,可以提供给有关部门参考。 相似文献
132.
DiPietro Janet A.; Caulfield Laura; Costigan Kathleen A.; Merialdi Mario; Nguyen Ruby H. N.; Zavaleta Nelly; Gurewitsch Edith D. 《Canadian Metallurgical Quarterly》2004,40(3):445
Longitudinal neurobehavioral development was examined in 237 fetuses of low-risk pregnancies from 2 distinct populations-Baltimore, Maryland, and Lima. Peru-at 20. 24. 28. 32, 36. and 38 weeks gestation. Data were based on digitized Doppler-based fetal heart rate (FHR) and fetal movement (FM). In both groups. FHR declined while variability, episodic accelerations, and FM-FHR coupling increased, with discontinuities evident between 28 and 32 weeks gestation. Fetuses in Lima had higher FHR and lower variability, accelerations, and FM-FHR coupling. Declines in trajectories were typically observed 1 month sooner in Lima, which magnified these disparities. Motor activity differences were less consistent. No sex differences in fetal neurobehaviors were detected. It is concluded that population factors can influence the developmental niche of the fetus. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
133.
高坝风险分析的事件树法 总被引:2,自引:0,他引:2
新世纪一批高坝将要在我国开工建设,这对我国的水电能源及国民经济的发展有着不可估量的作用,而高坝建设中,安全性是需要首先保证的。目前对高坝的风险分析方法有主观概率法、客观概率法等。从系统工程的角度出发,采用事件树方法对高坝的风险进行了探索研究,并给出了算例以说明该方法的有效性和实用性。 相似文献
134.
The scope of the paper is the assessment of the technical risk involved in long-term operation of power units. Detailed analyses have been conducted for steam turbine components. The sources and consequences of risk have been identified and the probability of turbine components failure calculated. The quantitative assessment of the risk has been made and possibilities of its reduction discussed. 相似文献
135.
O. L. Perevozchikova V. G. Tul'chinskii A. V. Kharchenko 《Cybernetics and Systems Analysis》2003,39(4):501-508
A statistical learning model is considered within the framework of the theory of uniform convergence of frequencies of errors in the case where the convergence is violated as a result of increasing the informativeness of training examples. Drawbacks of nonconstructive refinements of Vapnik-Chervonenkis estimates based on an assumption on the distribution law of violations are shown. A new approach to obtaining constructive estimates for mass data sets is proposed. 相似文献
136.
van der Ploeg Eleonore; Dorresteijn Sasja M.; Kleber Rolf J. 《Canadian Metallurgical Quarterly》2003,8(2):157
Workers in medium- or high-risk professions are often confronted with critical incidents at the workplace. The impact of these acute stressors may be serious and enduring. Many workers also experience chronic job stressors, such as work overload or role conflicts. This study examined the frequently neglected relationship of acute and chronic stressors with self-reported health symptoms, such as posttraumatic responses, fatigue, and burnout. This association was investigated in a sample of forensic doctors in the Netherlands (N = 84). It was found that the more traumatic events the respondents experienced, the more problems they reported in coping with the traumatic events. Chronic job stressors were associated with posttraumatic responses (intrusions and avoidances) and with burnout and fatigue. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
137.
Psychologists are often asked to testify in court. However, concerns have been expressed in both the legal and psychological literatures about the quality of these services. This article presents survey results comparing the practice patterns of generally licensed psychologists with those of specialist forensic diplomates in providing risk evaluations. Results suggest that general clinicians frequently perform these evaluations, but forensic diplomates use more modern risk instruments, are more aware of the scientific literature, and provide the court with more information about the scientific basis of their testimony. The implication of these results for legal professionals, psychologist training, and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
138.
ERP的实施与风险防范 总被引:3,自引:0,他引:3
在管理应用的广度方面,ERP超越了MRP的应用范围。文中指出了实施ERP系统的步骤及ERP实施中应注意的问题,强调企业有必要对风险有充分认识,建立一套行之有效的风险管理机制,从而提高了ERP系统的实施成功率,最终提高企业的管理水平。 相似文献
139.
浅谈施工企业如何提高投标报价能力 总被引:2,自引:0,他引:2
本文就施工企业如何提高投标报价能力,从编制企业施工定额、建立成本数据库、做好投标工作、加强施工过程管理、建立风险管理系统等几个方面提出一些建议。 相似文献
140.
把汽轮机轴承座松动的相关频段上不同频率谱的谱峰能量值作为故障信号的训练样本输入到LVQ网络中去,并由LVQ网络产生训练后不同的权重向量。由于竞争层神经元的权重分布不同,则权重分布图也不同,可根据不同的权重分布图来确认和诊断汽轮机轴承座松动故障的不同程度。 相似文献