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排序方式: 共有9799条查询结果,搜索用时 15 毫秒
991.
杨典超 《江汉石油职工大学学报》2013,26(5):104-107
外部环境诱因、市场地位弱势、机械制造比重大、风险管理意识不足、历史及体制影响等因素造成了江汉油田资金占用问题。资金占用,加深了资金供需矛盾,造成了资金浪费,易导致财务风险。要解决这一问题,就必须强化应收账款管理和存货管理。 相似文献
992.
上海轨道交通的线路数逐年递增,随之自动售检票系统的规模越来越大,如何管理由于自动售检票系统的应用软件版本不断升级带来的软件功能测试的管理问题亟待解决本文借鉴ITIL思想,提出一个针对软件功能测试的管理模型应用表明,该模型在上海轨道交通自动售检票系统的测试管理中是成功和有效的 相似文献
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995.
Jacquelyn K. McNett William F. Hunt Jason A. Osborne 《Canadian Metallurgical Quarterly》2010,136(5):535-541
Storm-water experts agree that the currently used best management practice (BMP) percent removal methodology metric has many flaws, and some have suggested using a BMP effluent concentration metric. This case study examines establishing an effluent target concentration for BMPs that relates to the health of macroinvertebrates in the receiving water. In North Carolina, 193 ambient water quality monitoring stations were paired with benthic macroinvertebrate health ratings collected in very close proximity. Water quality for the sites ranged from excellent to poor and was divided into three distinct ecoregions: Mountain, Piedmont, and Coastal. Statistically significant relationships were found in one or more ecoregions for dissolved oxygen, fecal coliform, NH3, NO2?3?N, total Kjeldahl nitrogen, total nitrogen (TN), and total phosphorus (TP). BMPs can then be selected and designed to meet these target effluent concentrations. Based upon this research, a development, and therefore set of BMPs, in Piedmont North Carolina could be required to release TN and TP effluent concentrations of 0.99 mg/L and 0.11 mg/L, respectively. These concentrations are both associated with “good” benthos health. The new method was most effective in the Piedmont ecoregion, however with more data collection, the Mountain and Coastal ecoregions may also benefit. 相似文献
996.
Jane Clary Marcus Quigley Aaron Poresky Andrew Earles Eric Strecker Marc Leisenring Jonathan Jones 《Canadian Metallurgical Quarterly》2011,137(3):190-198
Low impact development (LID) strategies are being encouraged in many communities as an approach to reduce potential adverse impacts of development on receiving streams. Many questions exist regarding how well various LID strategies perform in different settings, just as similar questions have been raised regarding performance of traditional stormwater best management practices (BMPs). Whereas historical focus on BMP performance has been water quality concentrations or loads, characterization of volume reduction benefits for both conventional and LID practices is increasingly an objective of researchers and stormwater managers. More than a decade ago, Urban Water Resources Research Council (UWRRC) members worked to develop a set of standardized monitoring and reporting protocols for traditional BMPs and to establish a master database for the purpose of evaluating BMP performance and the factors affecting performance. This effort culminated in the International Stormwater BMP Database (www.bmpdatabase.org), which contains data for more than 360 BMPs and continues to operate as a clearinghouse for stormwater BMP data and performance analyses. During 2008–2009, the International Stormwater BMP Database project expanded to better integrate LID into the database and develop a set of metrics that can be used to characterize BMP performance with regard to surface runoff volume reduction. This paper provides a condensed overview and progress report on the LID-focused effort, including the following topics: (1)?monitoring guidance for LID at the overall site development level, (2)?an overview of recent changes to the International Stormwater BMP Database to better accommodate LID studies, (3)?a summary of LID studies currently included in the database, and (4)?a proposed approach for evaluating performance of LID studies with regard to reducing surface runoff volumes. 相似文献
997.
近几年伴随着高速公路路网的大规模建设,通信系统网络越来越庞大,通信系统运行稳定性显得尤为重要。作为整个通信设备的重要组成部分——通信电源的作用也越发凸显。如何使得通信电源发挥最大的作用,为高速公路通信系统稳定运行提供保障,成为目前迫切需要思考的问题。本文主要针对通信电源在泉三高速公路运营中维护管理的一些特点,提出了初步的看法和解决方案。 相似文献
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999.
材料管理是建筑工程管理的重要组成部分,是控制工程质量、降低工程成本的有效途径。在材料管理的各个环节中,采用一些新方法,可以为所在工程提供低消耗、高效率、高收益的材料供应保障。 相似文献
1000.
Segmentation and recognition of Chinese bank check amounts 总被引:1,自引:0,他引:1
M.L. Yu P.C.K. Kwok C.H. Leung K.W. Tse 《International Journal on Document Analysis and Recognition》2001,3(4):207-217
This paper describes a system for the recognition of legal amounts on bank checks written in the Chinese language. It consists
of subsystems that perform preprocessing, segmentation, and recognition of the legal amount. In each step of the segmentation
and recognition phases, a list of possible choices are obtained. An approach is adopted whereby a large number of choices
can be processed effectively and efficiently in order to achieve the best recognition result. The contribution of this paper
is the proposal of a grammar checker for Chinese bank check amounts. It is found to be very effective in reducing the substitution
error rate. The recognition rate of the system is 74.0%, the error rate is 10.4%, and the reliability is 87.7%.
Received June 9, 2000 / Revised January 10, 2001 相似文献