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排序方式: 共有296条查询结果,搜索用时 31 毫秒
71.
车桥回转件CAPP系统中零件信息的输入 总被引:1,自引:1,他引:1
零件信息输入是CAPP系统中的一个关X技术问题。本文介绍了一个基于AUt0CAD环境下开发的零件信息输入方法一特征形京法,对商品化CAD环境下实现CAPP信息输入作了一些探讨。 相似文献
72.
论高新技术企业的产权制度创新 总被引:4,自引:0,他引:4
郑小平 《上海交通大学学报(哲学社会科学版)》2003,11(1):53-56,80
对高新技术企业进行产权制度创新不仅是企业实现跨越式发展和高效率运营的需要,也是激励企业人力资本和增强企业竞争力的需要。这一产权制度创新的内容主要包括:明晰企业初始产权,界定企业增量资产产权,确定合理的企业产权结构,以及建立开放型、多元化的企业产权。为此,在我国高新技术企业的产权制度创新中,可以实行结构性年薪制、实施股票期权制度、推行职工持股计划,以及试行可转化薪酬制度。 相似文献
73.
Applications on iterative control and multiple input multiple output (MIMO) system were developed. Two new charts derived from extrinsic information transfer (EXIT) chart were employed as the designing tools, which are called as output mutual information chart with defined iterative degree (DID) chart and near optimum output mutual information (NOMI) chart respectively. Different from the EXIT chart, they can show the iterative performance on the whole signal-to-noise ratio range with one single curve, whereas computation complexity is greatly reduced compared with conventional bit error ratio (BER) performance curve. The iterative control was implemented according to a near-optimum iterative degree vector determined by NOMI chart, the reasonability of uncertain parameters was analyzed in one MIMO system. The concepts were illustrated based on bit-interleaved coded modulation with iterative decoding (BICM-ID). 相似文献
74.
This paper explores the potential role of individual trip characteristics and social capital network variables in the choice of transport mode. A sample of around 100 individuals living or working in one suburb of Madrid (i.e. Las Rosas district of Madrid) participated in a smartphone short panel survey, entering travel data for an entire working week. A Mixed Logit model was estimated with this data to analyze shifts to metro as a consequence of the opening of two new stations in the area. Apart from classical explanatory variables, such as travel time and cost, gender, license and car ownership, the model incorporated two “social capital network” variables: participation in voluntary activities and receiving help for various tasks (i.e. child care, housekeeping, etc.). Both variables improved the capacity of the model to explain transport mode shifts. Further, our results confirm that the shift towards metro was higher in the case of people “helped” and lower for those participating in some voluntary activities. 相似文献
75.
James McConville 《Maritime Policy and Management》2013,40(1):1-2
This paper sets out the developments in world shipbuilding policy that have occurred in the past decade. It reviews and outlines the situation that existed in the late 1990s, when an Organization for Economic Co-operation and Development (OECD) agreement on the elimination of shipyard operating subsidies was tantalisingly close. After the Introduction, the second section provides a brief review of the development of the industry over the past three decades, setting the context for developments since 1997. The third section discusses the complaint of the European Union (EU) to the World Trade Organization (WTO) concerning the Republic of Korea's support for its shipbuilding sector, and its counterclaim over the EU's temporary defence mechanism (TDM). It is argued that the core of the EU's case at the WTO was flawed, and that the reintroduction of an operating subsidy via the TDM was a mistake. The only prospect for regularizing competition in this area lies in the negotiation of the OECD agreement that was completed, but not ratified, in 1994. Given the souring of relations between two of the main players in this area, the prospects for such a settlement seem remote. The fourth section uses Olson's theory of groups to argue that the European Commission's actions were driven primarily by industry pressure groups, and failed to consider the potential views of other European stakeholders, in particular the taxpayers. Given the failure of the EU's action at the WTO, the future direction of European shipbuilding policy will have to focus on strategies for internal development and improved industrial competitiveness. 相似文献
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孟玉芳 《青岛远洋船员学院学报》2013,(3):77-79
多媒体航海英语听说逆向教学是希望通过专业交叉,取长补短,共同探索一种新的航海英语听说教学和评估方式,寻找一种更能贴近航海实际、能够满足航海实际工作需要、更简单方便的教学模式.本文以消防和船员自救为试点,对这种模式进行探索和评估,同时也为航海英语评估的场景化考核方式作新的探索. 相似文献
80.
W. S. Homburger 《运输规划与技术》2013,36(3):187-201
This study analyzes data of traffic crossing San Francisco Bay and passing through the Berkeley Hills via Caldecott Tunnel to determine the effect of the opening in 1974 of the Bay Area Rapid Transit System (BART) transbay line. There was a sudden shift in trend lines in 1974; vehicle volumes dropped, transit patronage jumped, but total person trips in the short run followed roughly the trends of the previous eight years. Since 1974, the growth rate in person trips through the Berkeley Hills appears to have remained about the same, while transbay vehicle and transit traffic have increased at a more rapid rate. The increase in transit patronage is particularly noticeable between the morning and afternoon peaks and probably represents new trips by shoppers and sightseers. Whereas other factors, such as the increase in the price of gasoline between October 1973 and July 1974 may have contributed a little to the sudden change in the long‐range trends in 1974, it is believed that the major cause was the opening of the BART network to transbay travel. 相似文献