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101.
《The Journal of geography》2012,111(1):46-48
Abstract Full implementation of geography standards will require their adoption by all U.S. states and school districts for use in every school. Strategies for achieving this goal include: using the consensus process to its fullest, involving the energy and resources of geography organizations, and reaching out to others to help maximize the standards' influence. 相似文献
102.
安徽省矿业权实地核查实施及对策 总被引：1，自引：1，他引：0
针对目前安徽省实施矿业权勘查工作,根据全省矿业分布和矿业权资料的实际情况,分析安徽省矿业权的的现状,提出适宜的矿业权实地核查方案和测量勘界等作业步骤,达到少投入、大效益、成果优秀的核查目的,建立采矿权登记数据库,全面提高矿业权的管理水平,供同行们参考。 相似文献
103.
Restoring degraded grassland ecosystems is of great significance for the sustainable development of grassland ecological service functions and the sustainable and healthy development of regional economies and societies. Returning grazing land to grassland technology (RGLGT) is an important strategic technology for restoring degraded grassland ecosystems and achieving the sustainable development of the society and economy of pastoral areas in China. Researching the comprehensive evaluation system of the effects of RGLGT has an important significance for evaluating and adjusting national ecological policy. Based on collecting sample surveys from 221 farmers in 16 villages of 4 towns of Yanchi County, Ningxia Hui Autonomous Region in 2017, a model for evaluating the effects of implementing RGLGT was developed. The model included the characteristics of the technology, the ecological and social benefits of the technology, and the sustainability and economic benefits of the technology, it was used to complete a comprehensive effects evaluation of implementing RGLGT in Yanchi County that was based on use of the Analytic Hierarchy Process (AHP) method. The results showed that the comprehensive effect of implementing RGLGT is good overall and had a score of 0.5946. In terms of specific effects ranked from high to low, these were the ecological and social benefits of the technology, the economic benefits, the sustainability and the characteristics themselves. The implementation of RGLGT has resulted in good ecological and social benefits and economic benefits, but sustainability and characteristics of the technology are weak. 相似文献
104.
Formulation of a matrix‐valued force–displacement relationship which can take radiation damping into account is of major importance when modelling unbounded domains. This can be done by means of fundamental solutions in space and time in connection with convolution integrals or by means of a frequency dependent boundary element representation, but for discrete frequencies Ω only. In this paper a method for interpolating discrete values of dynamic stiffness matrices by a continuous matrix valued rational function is proposed. The coupling between interface degrees of freedom is fully preserved. Another crucial point in soil–structure interaction analysis is how to implement an approximation in the spectral domain into a time‐domain analysis. Well‐known approaches for the scalar case are based on the partial‐fraction expansion of a scalar rational function. Here, a more general procedure, applicable to MDOF‐systems, for the transformation of spectral rational approximations into the time‐domain is introduced. Evaluation of the partial‐fraction expansion is avoided by using the so‐called mixed variables. Thus, unknowns in the time‐domain are displacements as well as forces. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
105.
该文分析光纤接入网规划工作的具体任务及其性质 ,提出整合运用GIS技术和ES技术来建立智能型光纤接入网规划系统的思想。根据OAN规划的实际需要 ,定义IPSOAN的具体功能 ,探讨了智能型光纤接入网系统实现的关键算法 ,以VC集成开发环境和MapInfoGIS组件—MapX为开发平台 ,研讨IPSOAN的实现方法 相似文献
106.
107.
文章从以下 6个方面概要介绍了IGBP、IHDP与WCRP的一项新的联合计划———“全球环境变化与食物系统 (GECAFS)”的科学框架与实施战略 :(1)背景 ;(2 )GECAFS的概念框架 ;(3)GECAFS的科学主题 ;(4 )GECAFS的研究类型与“示范性项目” ;(5 )科学新领域 ;(6 )GECAFS计划与其它组织的资助关系及战略伙伴关系。 相似文献
108.
使用高质量、高压缩率的语音编解码器,可以在保证通话质量的前提下有效地提高通信系统的容量。这里首先介绍了基于共轭结构ACELP语音编解码算法,并针对该算法特点提出算法优化方法,如固定码本搜索优化,开环基音分析优化,运算移位溢出检查处理等;然后给出在TI公司16位定点DSP芯片TMS320VC549上实时实现该优化后算法的方案和过程,分析了编解码语音的质量和算法的性能,最后得出实时实现的结果。实验结果表明,优化后的CS-ACELP语音编码算法在定点DSP上的实时实现,能得到良好的语音音质,所用的资源和功耗极低。 相似文献
109.
l mechanics characters, and its constitutive relationship is relatively complex.Although through experimental study in almost a century, and increasingly profundity in cognition about mechanism of RC,the bond-slip relationship between rebar and concrete has not deeply studied in finite element analysis.In this paper,through selecting proper material consti- tutive relationship and bond-slip model,3-D finite element analysis mode 相似文献
110.