我国零售业发展的困境与出路

通过对我国零售业普遍存在的问题的研究与探讨，指出了我国零售业今后的发展出路，有针对性地提出了走出目前困境的对策。     

VPN技术的研究与应用现状及发展趋势

文章探讨VPN技术的研究与应用现状及发展趋势。首先,对主流VPN技术内核或标准的发展现状与趋势进行了分析,并简单介绍了商品化VPN产品;其次,阐述了VPN市场现状和发展趋势,并对现有厂商的VPN解决方案作了比较;最后,提出了典型企业VPN系统的应用模式,并对下一代VPN技术的发展趋势进行了展望。     

信息管理与信息系统专业建设与发展探讨

本文通过对信息管理与信息系统专业内涵的分析与理解;结合实际教学体会和思考,从专业的定位、培养目标,以及该专业建设中的课程建设、师资建设、教材与大纲建设和实验室建设等方面进行了探讨.     

Green leaf phenology at Landsat resolution: Scaling from the field to the satellite

Despite the large number of in situ, plot-level phenological measurements and satellite-derived phenological studies, there has been little success to date in merging these records temporally or spatially. In this research, we bridge this scale gap through higher resolution satellite records (Landsat) and quantify the accuracy of satellite-derived metrics with direct field measurements. We compiled fifty-seven Landsat scenes from southern New England (P12 R51) from 1984 to 2002. Green vegetation areal abundance for each scene was derived from spectral mixture analysis and a single set of endmembers. The leaf area signal was fit with a logistic-growth simulating sigmoid curve to derive phenological markers (half-maximum leaf-onset and offset). Spring leaf-onset dates in homogenous stands of deciduous forests displayed significant and persistent local variability. The local variability was validated with multiple springtime ground observations (r² = 0.91). The highest degree of verified small-scale variation occurred where contiguous forests displayed leaf-onset gradients of 10-14 days over short distances (< 500 m). These dramatic gradients occur in of low-relief (< 40 m) upland regions. The patterns suggest that microclimates resulting from springtime cold-air drainage may be influential in governing the start of leaf growth; every 4.16 m loss in elevation delayed spring leaf onset by 1 day. These microclimates may be of crucial importance in interpreting in situ records and interpolating phenology from satellite data. Regional patterns from the Landsat analyses suggest topographic, coastal, and land-use controls on phenology. Our results indicate that deciduous forests in the Providence, RI metropolitan area leaf out 5-7 days earlier than comparable rural areas. The platform-independent curve-fit methodology may be extended across platforms and field data. The methodologically consistent approach, in tandem with Landsat data, allows an effective scaling from plot to satellite phenological observations.     

动态网页开发工具的分析和研究

动态网页开发工具主要有ASP、PHP、JSP,本文介绍了它们的技术特点、应用范围和应用前景及它们之间的比较。     

城市人防警报监控系统软件设计和实现

主要介绍用VB实现无线通信的软件设计。并且提出了使系统应用程序更有效和可靠的方法。     

城市排水系统集成模拟研究进展

在回顾城市排水系统集成模拟研究发展和现状的基础上,结合可持续性城市排水系统理论,分析了现阶段城市排水系统集成模拟研究的局限和面临的问题。为了适应城市排水系统结构和功能的演变,实现系统的可持续性,今后城市排水系统集成模拟的研究应当完善对系统结构的描述,在集成模拟的过程中考虑不确定性因素对系统的影响,并构建高效能计算平台,解决城市排水系统大规模计算问题。     

对机械安全技术现状的分析及发展趋势展望

在对机械安全技术的发展简史及现状进行分析的基础上,对机械安全技术的发展趋势作出了基本预测.     

城市照明计算机无线监控系统

介绍了城市照明计算机无线监控系统的软、硬件组成(由监控中心、数据监控终端、无线通讯网、图像监视系统四部分组成)及其功能。通过对比系统安装前后的设施维护情况和运行的实际效果,说明了采用城市照明计算机无线监控系统替代传统控制方式管理城市照明设施,具有技术先进、功能完善、安全可靠、便于维护管理的特点,是城市照明设施管理的发展方向。     

论城市规划调控房地产的目标职能与作用机制

城市规划作为一项重要的政府职能,对房地产具有重要的调控作用.在市场经济条件下,城市规划调控房地产的基本职能有控制职能、引导职能、协调职能和保障职能.城市规划对房地产的调控机制可以概括为三个方面:房地产开发规划控制、房地产开发规划引导和房地产开发规划反馈.