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41.
The development of a Municipal Information System, or currently better known as a local spatial data infrastructure, is considered complex due to the required inter-institutional relationships. In many developing countries Geographical Information Systems (GISs) are introduced but the benefits are modest as no changes take place in technical and organisational structure of organisations. Digital databases and computer-aided design (CAD) maps are mushrooming in great variety within different private and public institutions, municipal organisations and even within single departments and with structures similar to the paper period and thus operating on a stand-alone basis.Many national mapping agencies are not able to provide large-scale digital urban base maps, while the absence or low quality of cadastres makes those basic core data sets unavailable or inaccessible. The result is that duplication and incompatible data are frequently observed and also donor-driven stand-alone projects have a limited impact through the lack of institutional embedding and are not able to mature from the project to the institutional level. However, a positive sign is that there is an increasing awareness among data producers and consumers that investments in the development of digital data sets should be combined to reduce costs and increase benefits from especially GIS, and information and communication technology (ICT) in general.Within Trujillo a long-term vision was developed to make full use of ICT and GIS to modernise all operations of the Municipality to increase the efficiency and effectiveness of its tasks. However, large investments are not feasible due to the very limited municipal budgets. To guarantee the support of the municipal council, short-term results are required. This paper describes three ‘products’ as part of the vision to develop through a step-by-step approach a local spatial data infrastructure for Trujillo.The three, rather different, products are:
1. fiscal cadastre, to increase municipal revenues through property taxation;
2. an ‘environmental atlas’ based on a compatible spatial and attribute data sets from a variety of organisations; and
3. a municipal website with interactive GIS and meta data information.
The paper concludes with some comments on the institutional and political requirements for the successful development of a local spatial data infrastructure and stresses that such an infrastructure is not a product but an incremental development process that will progress only in case such a process is simple, cost effective, user-friendly, and flexible with clear products.Political interest and institutional stability and genuine interest for inter-institutional cooperation will add much to the success of this process.  相似文献   
42.
A controlled clinical trial was conducted to investigate the efficacy effect of a chemical compound in the treatment of Premenstrual Dysphoric Disorder (PMDD). The data from the trial showed a non-monotone pattern of missing data and an ante-dependence covariance structure. A new analytical method for imputing the missing data with the ante-dependence covariance is proposed. The PMDD data are analysed by the non-imputation method and two imputation methods: the proposed method and the MCMC method.  相似文献   
43.
分析和研究政治语言的系统结构及结构要素之间的相互关系 ,是研究政治语言的重要内容 ,有利于更好地认识和把握政治语言。政治语言结构是一种特殊的层级系统 ,其要素包括符号、符号系统、符码、文本、语境和话语。政治语言结构的要素之间相互作用、相互关联 ,共同构成了政治语言的系统 ,并以其特有的方式表达政治意义 ,服务于政治活动  相似文献   
44.
Summary.  In longitudinal studies, missingness of data is often an unavoidable problem. Estimators from the linear mixed effects model assume that missing data are missing at random. However, estimators are biased when this assumption is not met. In the paper, theoretical results for the asymptotic bias are established under non-ignorable drop-out, drop-in and other missing data patterns. The asymptotic bias is large when the drop-out subjects have only one or no observation, especially for slope-related parameters of the linear mixed effects model. In the drop-in case, intercept-related parameter estimators show substantial asymptotic bias when subjects enter late in the study. Eight other missing data patterns are considered and these produce asymptotic biases of a variety of magnitudes.  相似文献   
45.
西部高校怎样更好实现计算机与物理实验的整合   总被引:2,自引:0,他引:2  
随着计算机的飞速发展,学校里出现了越来越多的多媒体教室;CAI计算机辅助教学、虚拟实验教学等各种软件更是蓬勃发展起来;很多教育工作者提出物理实验中计算机仿真教学、物理实验中应用计算机辅助教学等各种措施.作为西部高校,我们应该根据自身资金有限、学生基础比较薄弱等特点,更好的实现计算机与物理实验的整合.  相似文献   
46.
Summary. Semiparametric mixed models are useful in biometric and econometric applications, especially for longitudinal data. Maximum penalized likelihood estimators (MPLEs) have been shown to work well by Zhang and co-workers for both linear coefficients and nonparametric functions. This paper considers the role of influence diagnostics in the MPLE by extending the case deletion and subject deletion analysis of linear models to accommodate the inclusion of a nonparametric component. We focus on influence measures for the fixed effects and provide formulae that are analogous to those for simpler models and readily computable with the MPLE algorithm. We also establish an equivalence between the case or subject deletion model and a mean shift outlier model from which we derive tests for outliers. The influence diagnostics proposed are illustrated through a longitudinal hormone study on progesterone and a simulated example.  相似文献   
47.
企业经营决策会计理论方法体系之探讨   总被引:2,自引:0,他引:2  
企业经营决策会计是以系统论、信息论、控制论为理论基础 ,将企业划分为若干个子系统 ,运用现代科学管理设备和技术 ,对企业经营管理所涉及的内外部信息源进行定量分析、计算、对比和评价 ,为企业经营决策提供最佳方案  相似文献   
48.
数据挖掘与数据仓库在CRM中的应用   总被引:2,自引:0,他引:2  
介绍了客户关系管理的思想、功能组成 ,以及数据挖掘和数据仓库技术在客户关系管理中的应用  相似文献   
49.
明代后期社会经济架构内呈现出异动迹象。不仅在城镇中有了无人身依附关系的自由劳动力,而且出现在财宫原始积累上能发挥独特作用的产业资本。这些对于封建经济而言的“异质”,在清代初期并未消失,反而有所滋长,无论于手工生产与商贸活动,还是在资本运作渠道的拓展上,均有所增强,并清晰地显露出资本主义萌芽状态的经营性质。  相似文献   
50.
高校院系资料室的建设及其与校图书馆的共建   总被引:5,自引:0,他引:5  
高等院校的院系资料室是图书系统的组成部分,在承担院系教师和学生查阅资料方面,具有图书馆无可比拟的功能和作用。文章主要分析了高校院系资料室存在的问题以及其解决措施,并明确了院系资料室与图书馆之间的关系,对院系资料室的建设提供了借鉴。  相似文献   
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