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51.
刘国栋 《北方交通》2006,(11):87-89
阐述了为适应国有公路建设公司法人治理结构的要求,在财务管理方面应采用的理财模式。  相似文献   
52.
上海世博会园区设有综合管沟作为地下公用管线的汇集空间。其中西环路(K0+047~K0+498)长度451m的综合管沟标准段管节为工厂预制,现场拼装。该文着重介绍了现场拼装的施工工艺。此工艺具有效率高,风险小等显著优点,为类似工程施工提供参考。  相似文献   
53.
郑建恩 《中国水运》2007,5(8):180-181
税务部门传统的考核方法无法有效调动税务人员工作积极性,存在诸多弊端,枣庄市X区国税局以量化积分制考核破解考核难题,提高了工作绩效,更新了管理理念。  相似文献   
54.
章针对现在出版的沈从传记中有关他在西南联大任教时间及聘任职务上的混乱情况。通过西南联大原始件的记录。并结合提议聘请沈从到联大任教的当事人朱自清的日记等相关献资料.对沈从进入西南联大任教的时间、聘任的职务以及改聘为教授的时间作了详细的考证。同时对沈从在联大任教期间遇到的压力作了简单的分析。章为人们了解沈从抗战时期的思想和学创作的变化提供了一个参考。  相似文献   
55.
GB/T 11032—2020《交流无间隙金属氧化物避雷器》已于2021年7月1日开始实施.介绍GB/T 11032—2020中有关避雷器类型、型式试验、抽样试验等内容的变化情况,结合电气化铁道用避雷器的检验检测工作,重点分析适用于电气化铁道用避雷器的条款、技术参数及试验方法,包括重复转移电荷试验、内部部件绝缘耐受试验...  相似文献   
56.
This paper examines the possible placement of Energy Storage Systems (ESS) on an urban tram system for the purpose of exploring potential increases in operating efficiency through the examination of different locations for battery energy storage. Further, the paper suggests the utilisation of Electric Vehicle (EV) batteries at existing Park and Ride (P&R) sites as a means of achieving additional energy storage at these locations. The study achieves this through MATLAB modelling utilising captured GPS data and publically available information. This study examines the scenario of uni-directional substations with no interconnection between the overhead catenary for both directions of travel, and discusses the trade-offs between ESS size and required current limits.The results show the savings in both energy and basic CO2 emissions alongside the discussion of Return on Investment (RoI) that can be achieved through the potential installation of ESS at identified ideal locations along the tram network. Moreover, this may be extended to the use of EVs as stationary ESS sited at the existing P&R facilities. Further, the model may also be used to inform future infrastructure upgrades and potential improvements to air quality within urban environments.  相似文献   
57.
In 1992, scientists at National Estuarine Research Reserve (NERR) sites proposed establishing a national coordinated monitoring program that would attempt to identify and track short-term variability and long-term changes in representative estuarine ecosystems and coastal watersheds. Known as the NERR System-Wide Monitoring Program (SWMP), it currently consists of monitoring water quality and atmospheric variables over a range of spatial and temporal scales. Additional monitoring of ecological resources and land-water use will follow in subsequent components of the program. Water quality monitoring at NERR sites includes measurements of pH, conductivity, temperature, dissolved oxygen, turbidity, and water level. The NERR sites use data loggers that record at 30-minute intervals and relay measurements to internal memory. Standardized protocols assure that sampling, processing, and data management techniques are comparable among sites. Statistical techniques are being used to identify periodicity in water quality variables. Periodic regression analysis indicated that diel periodicity in dissolved oxygen is a larger source of variation than tidal periodicity at sites with less tidal amplitude. Tidal periodicity, however, is more important at sites with a tidal amplitude greater than 1 m. This finding suggests that natural processes controlling dissolved oxygen levels differ among sites depending upon tidal amplitude. Water quality data from the NERR SWMP have also been used to investigate occurrence of hypoxia. Results from analysis of water quality at several reserves indicate that hypoxia occurs but that the percentage of time that dissolved oxygen was less than 28% saturation varied substantially among sites and between years. Most of the hypoxic events occurred in summer but were also observed in winter and fall when low dissolved oxygen is usually not considered a problem. Without continuous monitoring by the NERR SWMP, many low dissolved oxygen events would have been missed, thus underestimating the duration and potential impact of this type of water quality variability. The NERR SWMP provides a unique opportunity to increase our understanding of how various environmental factors influence estuarine processes. Only by understanding how estuaries function and change naturally over time will we be able to predict how these systems respond to changes in climate and human-induced perturbations.  相似文献   
58.
文化产业园是文化产业发展的园区化、规模化的表现形式,建立并发展文化产业园可以促进区域文化产业的发展,拉动关联产业并增加经济产值,实现当地的经济、社会和文化的整体发展和内涵式增长。沈阳棋盘山文化产业园区自创建后成果斐然,但也存在基础设施不完善、产业集聚化程度低、示范基地带动作用不够明显等问题,应采取完善配套设施建设、突出产业特色、实现产业链发展、强化园区管理等措施逐步改进、完善。  相似文献   
59.
为降低柴油机的排放污染,使柴油机达到国IV以上排放要求,参考国际柴油机的排放技术,目前,主要有2条技术路线可供选择,即SCR技术路线和EGR技术路线。文章对这2种技术路线从结构特点、工作原理、优缺点进行比较分析,结果表明,柴油机在我国近期和远期,不同的车型应采取不同的技术方案,为我国柴油机达到国IV以上排放标准提供了参考。  相似文献   
60.
由于地形地貌的原因,城市地面道路断面通常情况下均为常规设计。但在局部复杂地形、地质条件下,也会碰到一些常规断面设计方法无法实施的困难,在昆明320国道(眠山-车家壁)段改扩建工程中,电厂大沟鱼塘段断面设计时就碰到了该问题。该文对工程建设中碰到的问题,以及采取的方法进行了总结,以供借鉴。  相似文献   
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