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541.
陈优珍 《铁路通信信号工程技术》2009,6(1):57-58
比较各种灌封材料的优缺点,研究在铁路客专信号产品生产中应用硅树脂凝胶灌封的关键工艺,包括PCBA表面清洁、温度控制、配方管理和控制、抽真空、灌封有效期管理和固化过程管理等,特别提出灌封有效期管理的新观点,并进行实践和总结。 相似文献
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Liang Chen 《Maritime Policy and Management》2013,40(3):219-230
Almost a decade since port corporatization was introduced in Australia it is becoming clear that initial objectives are not being realized. This paper explores some of the legal and legislative causes, the effect on port operation and investigates what necessary conditions are required to deliver an effective corporatized port business. The paper argues that effective corporatization is a product of effective legislation—one which, while emulating private sector business practices—can deliver a business model that is innovative, entrepreneurial, commercially oriented and free from self-serving political constraints. The legislation and corporatized artifacts in Australian mainland ports have failed, in general, to deliver this. Arguably, the legislation has, in fact, created a model with inherent flaws and serious contradictions. The legislation enacted is such that while it has set in place a model that articulates commercial objectives, the model created is in fact one in which political objectives may override commercial ones; where strategy may be determined by a bureaucratic elite without the requisite skills and insights, and the resultant strategy appears ad hoc; and a corporate culture that frequently has failed to transcend that of the statutory authority and public utility model. This paper will test these assertions against the developments in the port of Melbourne. 相似文献
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陈春意 《广州航海高等专科学校学报》2001,(1):81-83
在高校后勤社会化改革中,属学校所有的国有资产应对其整体进行评估,确定后勤企业的资产总值。学校可按其所占份额提取利润,防止国有资产流失。 相似文献
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Diwakar Gupta Hao-Wei Chen Lisa A. Miller Fajarrani Surya 《Transportation Research Part A: Policy and Practice》2010,44(4):201-217
State agencies responsible for ADA-eligible paratransit services are increasingly under pressure to contain costs and maximize service quality. Many do not operate vehicles themselves; instead, they contract out the provision of services. Contractors are paid for each hour of service. They are responsible for hiring crew, forming routes, dispatching, and operating and maintaining agency-owned vehicles. In the Twin Cities of Minneapolis and Saint Paul, Metro Mobility, the agency responsible for providing paratransit services, requires contractors to use agency-approved software for booking trips dynamically and sets parameters that guide contractors’ practices. Customer trips booked in this fashion may not utilize capacity in the most efficient manner. Therefore, beginning with the daily trip schedules generated by the software, this paper proposes two approaches for improving the efficiency of paratransit operations and estimates the benefit of using these approaches via experiments that utilize Metro Mobility data. The first approach re-optimizes routes developed at the end of each day. The second approach evaluates the benefit to state agencies of selectively using non-dedicated service providers such as taxis. Both approaches are tested on actual data obtained from Metro Mobility. The study shows that a conservative estimate of savings from re-optimization would be approximately 5% of Metro Mobility’s operating costs. Savings from the use of taxis are smaller and in the range of hundreds of dollars per day. 相似文献
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