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81.
上海市在用车监测与维修制度探讨 总被引:1,自引:0,他引:1
根据上海市机动车辆的管理现状,提出上海市在用车I/M制度体系网络、监测方法、数据收集网络与“通过/不通过”排放限值方面的基本设想,为建立一个真正有效的在用车监测与维修制度提供依据。 相似文献
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论述了塑料模具标准件、通用件制造工艺数据库的开发过程。利用C++编程实现对数据库的检索、管理及用户界面设计,利用SQLServer建立工艺数据库,运用API编程技术完成工序图生成和编辑,采用ADO技术对数据库进行访问,以及系统的功能。 相似文献
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程琼 《湖南环境生物职业技术学院学报》2006,12(1):42-46
2002年7月美国通过了关于会计和公司治理一系列重大改革的索克斯法案(SOX Act),该法案以加强公司治理、强化信息披露为核心,主要内容是强化对高级管理人员的监管和防止外部审计失败.本文简单系统地介绍和分析了该法案中重要措施的相关内容和出台的原因,以期对我国当前公司治理和审计业发展有所启迪和帮助. 相似文献
87.
V. Krivtsov R. Watling S. J. J. Walker D. Knott J. W. Palfreyman H. J. Staines 《Ecological modelling》2003,170(2-3):393
Since 1994 data on fungal fruiting have been gathered in the Dawyck Botanic Garden outside Edinburgh, including that for eight plots within a 7.5 ha wood, which has been left unmanaged in order to investigate relationships amongst fungal succession, habitat characteristics and local weather patterns. The climatic data are provided by a small meteorological station situated on site. To handle nearly 4000 entries of data so far collected a computer database was constructed. This assists querying of the information so that changes in fungal communities and patterns of succession can be observed, and the relevant data extracted for further analysis. To aid in this analysis, and to give the user full control over editing, updating and querying the database, a special computer program was compiled.Analysis of the database records revealed that the currently known Dawyck fungal community comprises over 620 different taxa, and the species list increases every year. Although some species of mycorrhizal fungi showed high specificity towards their preferred host either at species (e.g. Lactarius blennius with beech, Lactarius quietus with oak, Russula fellea and Russula mairei with beech), or at genus level (e.g. Suillus spp. with Pinaceae), some other common fungi (e.g. of the genus Amanita) were found to have very wide host ranges. In addition, unusual mycorrhizal associations have also been recorded. A lime tree (Tilia), which is supposedly primarily endomycorrhizal, has been found regularly associated with Russula cyanoxantha, Russula parazurea, Russula pectinata and Inocybe fastigiata. Many common Scottish fungi were found to be associated with introduced exotic trees, which is illustrated on the example of Pseudotsuga menziesii (Douglas Fir).The software created utilises the Microsoft Office suite of programs. Microsoft Access was used to construct the database, and Microsoft Excel was used for statistical investigations. The software was programmed using Microsoft Visual Basic, and provided a means of extracting the necessary data stored in Access and controlling the formulae used in Excel for their analysis. The recorded seasonal patterns of fungal fruiting was successfully described by a simulation mathematical model comprising differential and algebraic equations. This model may now be used as a submodel within more complex models describing terrestrial ecosystem processes. Examples of model simulations and sensitivity analysis are given and implications for future research discussed. 相似文献
88.
Ian Boustead 《Journal of Cleaner Production》1993,1(3-4)
This paper examines the minimum essential requirements that must be satisfied when a database is established for life cycle inventory calculations. It shows that the format of the database is governed by the physical requirements of the system being examined, by the need to include iterative calculations within the analysis and by the demands of the final data presentation. 相似文献
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K. Hood R.A. Perez H.E. Cieplinski T.V. Hromadka G.E. Moglen H.D. McInvale 《Journal of the American Water Resources Association》2019,55(1):89-101
Earthen embankment dams comprise 85% of all major operational dams in the United States. Assessment of peak flow rates for these earthen dams and the impacts on dam failure are of high interest to engineers and planners. Regression analysis is a frequently used risk assessment approach for earthen dams. In this paper, we present a decision support tool for assessing the applicability of nine regression equations commonly used by practitioners. Using data from 108 case studies, six parameters were observed to be significant factors predicting for peak flow as a metric for risk analysis. We present our work on an expanded earthen dam break database that relates the regression equations and underlying data. A web application, regression selection tool, is also presented to assess the appropriateness of a given model for a given test point. This graphical display allows users to visualize how their data point compares with the data used for the regression equation. These contributions improve estimates and better inform decision makers regarding operational and safety decisions. 相似文献