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41.
An evolving understanding of ecological processes, together with ambiguities in National Park Service policy, have led to multiple interpretations of the role of management in our large natural area National Parks. National Park Service management policies must be dynamic and responsive to changes in scientific knowledge and societal values. We propose that the principal aim of NPS resource management in natural areas is the unimpeded interaction of native ecosystem processes and structural elements. The case of the changing role of natural fire management is used as an example in developing this rationale.  相似文献   
42.
传统的湿度表计算方法费时费力,而且误差较大。本文采用VB6开发了湿度表计算软件包,大大提高了工作效率,实现计算、绘图、打印一次完成,彻底解决了防护时间试验中的一个难题。  相似文献   
43.
基于通用无线分组业务(GPRS)的油田生产安全监控系统   总被引:5,自引:0,他引:5  
笔者以油田安全监控系统研发为背景,阐述GPRS(通用无线分组业务)技术的特点及安全监控系统的作用,提出基于GPRS的油田生产安全监控系统的技术方案,系统组成和监控软件的设计,由现场监控终端、GPRS网络、监控中心服务器构成的系统。对油井、抽油机、计量站点的工艺参数,设备工作状态,泄漏,防盗等实现远程监控。该系统在油田生产安全中发挥重要作用,具有实用价值和推广意义。  相似文献   
44.
昆山城市化与生态系统服务的关系定量研究   总被引:2,自引:0,他引:2  
在通过对昆山市1990~2006年城市化水平和生态系统服务价值变化评价的基础上,分析区域城市化与生态系统服务之间的耦合关系。结果表明:昆山的城市化相对水平在研究年份内不断提高,从1990年的0.18上升到2004年的0.60;用价值量表征的生态系统服务水平在研究年份的变化呈先下降后上升的趋势;区域的生态系统服务相对水平与城市化相对水平之间的关系呈不规则的"U"型特征,二者的关系可以用方程式y=-2.5873x4+5.2542x3+0.4227x+0.98(R2=0.89)较好的表征。  相似文献   
45.
This paper presents a new perspective on the reuse businesses of independent reuse business companies (IRBCs) in Japan. A majority of previous studies on reuse and remanufacturing have focused on the businesses of original equipment manufacturers (OEMs). During the past twenty years, however, in Japan, IRBCs have grown rapidly, especially those that launched new types of secondhand shops. The author proposes that the reuse businesses of IRBCs can provide useful information for academics, OEMs, and policy makers. A key finding is the strategies developed by IRBCs to ensure the volume of used products collected and to stimulate demand for used products. This paper compares the features of IRBC reuse businesses with those of OEMs, and discussed the results and implications of an interview survey with select IRBCs.  相似文献   
46.
目前,风暴潮灾害的数值模拟给出的海量数据结果往往使得研究者难以理解,阻碍研究工作的深入进行,同时从应用角度也不能满足对灾害进行实时可视化的需求.因此,本文针对风暴潮灾害数值模拟的计算格式和结果数据特点,探讨了Web Service技术和可视化处理技术基础上为研究人员提供实时的风暴潮灾害数值模拟以及水位、流场的时空分布可...  相似文献   
47.
"环保管家"模式的提出和推广是贯彻落实绿色发展的生动实践。本文在分析园区环境管理现状的基础上,探讨了园区"服务管家"的服务内容以及"环保管家"模式推广的建议,对完善"环保管家"服务园区体制机制具有积极的现实意义。  相似文献   
48.
49.
The scientific literature regarding HEMS (Helicopter Emergency Medical Service) planning lacks a method for defining optimal sites for helipads that takes into account risk distribution and hospital location. Such a method could minimise overall rescue time in emergency situations. In this paper a method that supports the decisions taken by disaster planners and managers is developed, focusing on the quantification of necessary air resources for the management of some probable calamities. Given a region characterised by a natural and non-natural disaster risk map, along with a comprehensive transport system (also characterised by a risk map), a set of emergency destinations (hospitals), a set of heliports/helipads dislocated on the territory and a number of available HEMS rotorcraft, the aim of the paper is to assess the adequacy of the VTOL/FATO (Vertical Take-Off and Landing/Final Take-Off and Landing Area) system in order to deal with a set of possible emergencies.  相似文献   
50.
Acadia National Park was one of the 14 sites included in the Park Research and Intensive Monitoring of Ecosystems network (PRIMENet). For eight years the EPA monitored ultraviolet (UV) radiation at this site, with the National Park Service (NPS) sponsoring a total climate and air monitoring station. Under the auspices of PRIMENet, research projects were initiated that investigated the effects of UV on amphibians, determined watershed mass balances, and developed a model of deposition along an elevational gradient. The monitoring data and research results have been used by park management to protect vegetation and water resources from ozone and deposition. These data are now being used to develop a “vital signs” monitoring program under the NPS’ Inventory and Monitoring Program. These data sets have been used in regional, national and international programs to protect human health and resources from air pollution. Public outreach has been accomplished through web site resources and via the Schoodic Education and Research Center.  相似文献   
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