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31.
日本稀土贮氢电池现状和发展趋势   总被引:3,自引:0,他引:3  
本文论述了日本稀土贮氢电池的生产现状、市场分析和发展趋势。  相似文献   
32.
校园网是高校重要的信息化平台,在教育教学中发挥了巨大作用,校园网对丰富教学手段、加快信息处理、提高工作效率、减轻劳动强度,实现资源共享都起到特殊的作用,同时近年来校园网在运行过程中也面临着各种安全威胁,从我国高校校园网络安全的现状分析入手,建议性地提出网络安全解决方案。  相似文献   
33.
本文讨论了北京通信DCN的现状及特点,阐述了北京通信DCN业务类型的变化趋向及下一步发展的设想和网络结构的优化建议。  相似文献   
34.
ABSTRACT

Total quality management (TQM) has been increasingly accepted as a management philosophy. Criteria such as those contained in the Malcolm Baldrige National Quality Award (MBNQA) often guide TQM implementation. However, reports indicate that fully assessing TQM efforts is difficult and hiring experts to help with this task is expensive. Using survey instruments is an attractive alternative to full-scale assessment. Despite the availability of many papers covering organizational performance assessment, few instruments specifically address TQM evaluation. Furthermore, none of the TQM assessment instruments has been subjected to rigorous validation; thus, only modest confidence can be placed in results obtained from their use. This article proposes a quick and cost-effective instrument that is a simple questionnaire designed to assist organizations in conducting self-evaluations of their TQM programs. The proposed instrument is based on the seven categories of the MBNQA criteria and was developed in cooperation with the Excellence in Missouri Foundation, which administers the Missouri Quality Award (MQA). This article highlights how questionnaire results can be used to guide further TQM implementation efforts.  相似文献   
35.
Stock trend prediction is regarded as one of the most challenging tasks of financial time series prediction. Conventional statistical modeling techniques are not adequate for stock trend forecasting because of the non-stationarity and non-linearity of the stock market. With this regard, many machine learning approaches are used to improve the prediction results. These approaches mainly focus on two aspects: regression problem of the stock price and prediction problem of the turning points of stock price. In this paper, we concentrate on the evaluation of the current trend of stock price and the prediction of the change orientation of the stock price in future. Then, a new approach named status box method is proposed. Different from the prediction issue of the turning points, the status box method packages some stock points into three categories of boxes which indicate different stock status. And then, some machine learning techniques are used to classify these boxes so as to measure whether the states of each box coincides with the stock price trend and forecast the stock price trend based on the states of the box. These results would support us to make buying or selling strategies. Comparing with the turning points prediction that only considered the features of one day, each status box contains a certain amount of points which represent the stock price trend in a certain period of time. So, the status box reflects more information of stock market. To solve the classification problem of the status box, a special features construction approach is presented. Moreover, a new ensemble method integrated with the AdaBoost algorithm, probabilistic support vector machine (PSVM), and genetic algorithm (GA) is constructed to perform the status boxes classification. To verify the applicability and superiority of the proposed methods, 20 shares chosen from Shenzhen Stock Exchange (SZSE) and 16 shares from National Association of Securities Dealers Automated Quotations (NASDAQ) are applied to perform stock trend prediction. The results show that the status box method not only have the better classification accuracy but also effectively solve the unbalance problem of the stock turning points classification. In addition, the new ensemble classifier achieves preferable profitability in simulation of stock investment and remarkably improves the classification performance compared with the approach that only uses the PSVM or back-propagation artificial neural network (BPN).  相似文献   
36.
《Ergonomics》2012,55(9):605-618
When most of the driving tasks are performed automatically, a driver's level of alertness may decline, as has been pointed out in the study of the phenomenon called ‘highway hypnosis’. One possible countermeasure is to periodically vary the speed (Wertheim 1978), but the authors have not found any studies that directly assess the effectiveness of this countermeasure. The objective of our study has been to provide empirical evidence regarding the effects of this strategy on the level of driver activation on a motorway route in real traffic. In the present study activation level as indexed by a relative measure based on slow EEG activity tended to be significantly higher when speed was modified periodically than when it remained constant. In addition, this index tended to be progressively higher when the speed was constant during the first part of the route, while the same thing did not occur when the speed was modified periodically. Finally, no significant differences between the constant and varying speed conditions were obtained with respect to any of the cardiovascular indices related to the effort put into driving and the stress experienced in the situation.  相似文献   
37.
38.
《Soils and Foundations》2014,54(4):648-656
By using the piezocone penetration test (PCPT or CPTu), one can develop not only a better understanding of the soil stratification, but also an understanding of soil behavior parameters related to soil compressibility, as well as soil strength. This paper describes a case study that utilizes incomplete piezocone dissipation test to estimate status of consolidation of a soil deposit. Incomplete pore pressure dissipation record of PCPT is extrapolated on an inverse time scale (1/t method) to estimate the “in situ” pore pressure and “residual excess” pore pressure. No case study has been reported in open literature where this methodology has been utilized to estimate the status of consolidation of the soil deposit. In this paper, the 1/t method was verified using dissipation data from rigorous calibration chamber tests and field test data.  相似文献   
39.
沙河工业园经过十余年的发展,取得了较好的成绩。但随着城市总体规划的修编,沙河工业园在区域发展中的地位、角色,发生了重大的变化,园区发展面临转型、升级的新形势。本文以沙河工业园为例,提出了针对老工业园的改造升级、转型发展的策略。  相似文献   
40.
本文对聚羧酸减水剂的发展研究现状进行阐述,继而根据聚羧酸减水剂的分子结构、合成原理及相关的性能关系给出其发展状况,并加以探讨,然后进一步提出聚羧酸型减水剂所要面临的问题和研究趋势。  相似文献   
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