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161.
City hazardous gas monitoring network 总被引:2,自引:0,他引:2
In our today's societies, many dangerous chemicals are produced and transported. Due to the vast use of chemicals, more chemical accidents are taking place with huge losses. In this study a city hazardous gas monitoring network was designed to detect the dispersion of toxic and combustible gases in the primary stages. The network could cover hazardous chemical facilities, important hazardous chemical routes, warehouses and special locations which may be the targets of terrorist attacks. The network is consisted of several local networks and a central control panel complex. Each local network has a local control panel in the center and many detectors and sounders around it at distances less than 3000 m that communicate with the local control panels wirelessly. In each location there are two types of gas detectors, toxic and combustible, and a sounder which are equipped with a wireless, radio frequency modem allowing the units to communicate readings and other information on a real-time basis with a remotely located local control panel. High sensitive Photo Ionization Detectors, PIDs, are used to provide fast and low-level on-site screening for chemicals contamination. Combustible gas detectors are the second choice to sense the combustible gas and verify the readings of PIDs in this regard. The central panel consists of several connected control panels work uniquely helping a computer set and the appropriate software and communicate with local control panels via telephone lines. All of the network components are shown on the monitor of central panel with special symbols by geographical information system program. The system is fully addressable so that the high level detection of a detector produces a blinking color double-circle around its symbol in GIS plan. In case of high level gas detection, a team of experts who are fully equipped with different portable detectors depart to the site to test the field to identify the chemicals. All readings of detectors are saved in a data bank and then analyzed to find any chemicals spills and leakages. The network was simulated by a special program so that the components of local networks and the central panel are shown in separate windows. By clicking on one detector on environmental window the formerly designed responses will be activated in central panel window. 相似文献
162.
生态旅游作为“保护生态”和“发展经济”双赢理念的新兴旅游类型,被西部各省(区、市)所关注并将其定为本地区发展的主导产业.通过对西部地区的生态旅游资源优缺点、市场定位、产品转化及空间布局的分析,初步勾画了西部生态旅游业的发展前景,并提出相应地发展策略. 相似文献
163.
湛江南珠产业振兴战略 总被引:1,自引:1,他引:1
在我国珍珠产业中,南珠具有举足轻重的地位.在分析湛江南珠产业取得成绩的基础上,详细论述了目前存在的密集养殖、种苗退化、场地老化、产品质量下降、加工技术落后、经济效益低等问题,进一步提出了振兴湛江南珠产业的战略对策. 相似文献
164.
Kazuo Kamura Yu Hara Bulent Inanc Masato Yamada Yuzo Inoue Yusaku Ono 《Journal of Material Cycles and Waste Management》2005,7(2):66-70
It is always possible for impermeable layers to exist in landfills. When they do, the properties of the solution at the exit of the leachate-collection system might not accurately reflect the overall properties of the landfill. This study examines whether resistivity monitoring is effective for determining the influence of impermeable layers on the leachate. The test cell used in this study was filled with waste made up mainly of incinerator ash and shredded incombustible material. Three lines of resistivity sensors were laid in the uppermost layer of the fill. A resistivity profile was recorded periodically from each of these lines. The water-table level and leachate properties were measured concurrently. Leachate conductivity was mainly controlled by concentrations of the main ions, and it correlated inversely to variations in resistivity. Temporal changes in the resistivity of the fills are an excellent means of assessing the leaching in fills. Monitoring the properties of leachate, combined with resistivity profiling, is extremely useful for interpreting the temporal changes of properties in landfills containing impermeable layers. 相似文献
165.
针对传统的污染排放数据指标计算方法存在的问题,提出污染物排放指标应根据排污强度和经济指标确定的新思路,同时提出污染物排放指标数据的快速测算模型设计.建议通过环境监测数据或物料衡算数据确定每个排污单位的平均排污强度,作为计算机处理的参数,再由该排污单位申报每月的经济指标(产量或产值),输入计算机计算其产污量、排污量和去除量.实施计算机管理的关键是选取适当的数据计算模型.新思路应该能够规范计算程序,建立污染源动态数据库,对排污数据实行有效的统计分析. 相似文献
166.
A data analysis of three major Korean cities was conducted to assess roadside inhalable particulate matter 10 μm or smaller
in aerodynamic diameter (PM10), including temporal and meteorological variations, over a recent period of 4 to 6 years. The yearly roadside PM10 concentrations presented a well-defined increasing trend or no trend depending on the roadside monitoring station. Most mean
values exceeded or approximated the Korean standard of 70 μg/m3 per year for PM10. A representative roadside diurnal trend was characterized by a distinct morning maximum. In most cases, the Sunday roadside
concentrations were similar to or somewhat lower than the weekday concentrations, and the PM10 concentrations presented a well-defined seasonal variation, with the maximum concentration in March. The monthly maximum
concentrations observed in March were most likely attributable to Asian dust storms. In two metropolitan cities (Seoul and
Busan), the frequency of days with roadside PM10 concentrations exceeding the standard of 150μg/m3 per 24 h was much lower for the roadside monitoring stations than for the residential monitoring station, whereas in the
third city (Daegu), this result was reversed. Interestingly, the average maximum concentrations observed for the roadside
sites in Seoul and Busan during March were higher than those for the residential sites, suggesting that the roadside concentrations
responded more to the dust storms than the residential areas. The relationship between the pollutant concentrations and five
important meteorological parameters (solar radiation, wind speed, air temperature, relative humidity, and precipitation) showed
that the number and type of meteorological variables included in the equations varied according to the monitoring station
or season. Finally, the current results confirmed that attention should be given to the PM10 exposure of residents living near roadways. 相似文献
167.
The development and effective introduction of strategies designed to ensure the ecologically and economically sustainable utilization of coastal and marine resources is perhaps the major challenge for Small Island Developing States (SIDS). In response, the 1994 Barbados Programme of Action (BPoA) called upon the SIDS to implement appropriate coastal and marine strategies and, crucially, ensure that such strategies were integrated into sustainable national development plans (NDPs). This article examines the extent to which contemporary NDPs and donor support programmes have incorporated the fisheries sector — arguably the most important coastal/marine resource for many SIDS — into such documents. Applying an assessment methodology, originally developed to identify levels of environmental mainstreaming within World Bank country assistance strategies to NDPs and donor support programmes, we are able to identify those SIDS who have most effectively integrated the fisheries sector into such documents. Comparison with data indicating the importance of the sector to the national economy (in terms of generating foreign exchange, employment generation and/or supporting domestic protein consumption levels) enables us to pinpoint those countries with substantial fisheries sectors, but a correspondingly lower than expected degree of sectoral mainstreaming. We suggest that the January 2005 review of the BPoA offers an opportune moment for such countries to redress these omissions. 相似文献
168.
Dalia Streimikiene 《Natural resources forum》2005,29(4):322-333
This article summarizes some of the results from the application of the indicators for sustainable energy development (ISED) tool for analyzing Lithuania's energy sector, in terms of trends, setting energy policy goals and monitoring progress towards these goals. This experience illustrates the potential applicability of the ISED methodology for energy policy development in economies in transition, using Lithuania as an example. The article presents a summary of the results achieved and conclusions arrived at from the analysis of six priority areas in the context of the research project coordinated by the International Atomic Energy Agency, and provides recommendations for the development of sustainable energy policy using the ISED approach. 相似文献
169.
170.