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101.
102.
A decision support system (DSS) has been developed to assist expert and non-expert users in the evaluation and selection of
eco-engineering strategies for slope protection. This DSS combines a qualitative hazard assessment of erosion and mass movements
with a detailed catalogue of eco-engineering strategies for slope protection of which the suitability is evaluated in relation
to the data entered. The slope decision support system (SDSS) is a knowledge based DSS in which knowledge is stored in frames
containing rules that can evaluate the available information for a project, stored as project specific information (PSI) in
a data file. The advantages of such a system are that it accepts incomplete information and that the qualitative nature of
the information does not instil the user with a sense of unjustified exactitude. By its multidisciplinary and progressive
nature, the DSS will be of value during the initial stages of an eco-engineering project when data collection and the potential
of different eco-engineering strategies are considered. The accent of the output of the DSS is on the application of eco-engineering
strategies for slope protection as an environmentally-friendly solution aiding sustainable development. For its acceptance
within the engineering community, the DSS needs to prove its predictive capacity. Therefore, its performance has been benchmarked
against successful and unsuccessful cases of slope stabilisation using eco-engineering. The target audience and the areas
of application of this DSS are reviewed and the strategies for further development in this area suggested. 相似文献
103.
104.
Groundwater study using remote sensing and geographic information systems (GIS) in the central highlands of Eritrea 总被引:3,自引:1,他引:3
Remote sensing, evaluation of digital elevation models (DEM), geographic information systems (GIS) and fieldwork techniques were combined to study the groundwater conditions in Eritrea. Remote sensing data were interpreted to produce lithological and lineament maps. DEM was used for lineament and geomorphologic mapping. Field studies permitted the study of structures and correlated them with lineament interpretations. Hydrogeological setting of springs and wells were investigated in the field, from well logs and pumping test data. All thematic layers were integrated and analysed in a GIS. Results show that groundwater occurrence is controlled by lithology, structures and landforms. Highest yields occur in basaltic rocks and are due to primary and secondary porosities. High yielding wells and springs are often related to large lineaments, lineament intersections and corresponding structural features. In metamorphic and igneous intrusive rocks with rugged landforms, groundwater occurs mainly in drainage channels with valley fill deposits. Zones of very good groundwater potential are characteristic for basaltic layers overlying lateritized crystalline rocks, flat topography with dense lineaments and structurally controlled drainage channels with valley fill deposits. The overall results demonstrate that the use of remote sensing and GIS provide potentially powerful tools to study groundwater resources and design a suitable exploration plan.The online version of the original article can be found at 相似文献
105.
Although the logistics industry provides critical services to all sectors of the economy, few studies exist in economic geography that examine and explain the organizational dynamics of this industry. This article highlights the significance of the logistics industry in contemporary industrialization and argues that an enriched understanding of the interaction between technology and space can be achieved by examining the evolution of an industry that plays a central role in the contemporary economy. We focus on dimensions that are identified as particularly important: organizational, geographic, and risk and security. 相似文献
106.
Christine S McCulloch 《Area》2006,38(1):24-33
Public participation in transparent decisionmaking has been proposed as a panacea for environmental protection. Bargaining theory suggests drawbacks to transparency such as hardening of attitudes and intransigence. Yet achievement of consensus on environmental values for integrated water resource management demands public involvement. Historical study of attempts to prevent reservoir construction in upland valleys designated for protection of nature suggests that 'closed-door' bargaining proved more effective for environmentalists than open, public debate. Records now open for analysis of disputes over Teesdale and Farndale, 1950–1970, allow comparisons to be made between behind-the-scenes deliberations and 'open-door' public discussion. The ambition of progressing from public participation to devolution of environmental decisionmaking and responsibility to the local scale demands more conceptualization of the process of decisionmaking on water resource development. 相似文献
107.
This study investigates the extent to which people's views on the causes and preventability of earthquake damage might be influenced by their degree of exposure to hazard as well as what information they have been given about the hazard. The results show that the provision of hazard zoning information influences judgements on preventability and causes of damage, but this effect depends on the degree of hazard faced by residents. In low hazard zones, information leads to the view that causes are manageable, whereas in high hazard zones information may induce a degree of fatalism. The use of public information in risk management needs to take into account the degree of risk faced by the recipients. 相似文献
108.
The Florida State University (FSU) multimodel superensemble forecast is evaluated against several other operational weather models for the Southeast Asia region. The superensemble technique has demonstrated its exceptional skills in forecasting precipitation, motion and mass fields compared to either individual global operational or ensemble mean forecasts. The motion field investigation for the season of 2001 reveals that the superensemble forecasts are closer to the observed data compared to the other global member operational models through its low systematic errors at the 850 hPa level. The FSU multimodel superensemble forecasts exhibit the lowest root mean square errors (RSMEs), the highest correlation against the best observed data and the lowest systematic errors compared to the other operational model members. These forecasts have the potential to provide better daily weather predictions over the Southeast Asia region, particularly during the early northeast monsoon that often causes heavy rainfall in the equatorial part of the Southeast Asia region. 相似文献
109.
Spatial assessment and redesign of a groundwater quality monitoring network using entropy theory, Gaza Strip, Palestine 总被引:3,自引:0,他引:3
Using entropy theory, a methodology was developed for the evaluation and redesign of groundwater quality monitoring wells in the Gaza Strip in Palestine. Essential to the methodology is the development of a Transinformation Model (TM) which yields the amount of information transfer and the dependency between the wells as a function of distance. The TM parameters, such as the minimum transinformation and the range, were employed for evaluating the network which revealed that most of the distances between wells were less than the range. It also indicated that a high percentage of redundant information existed in the network. Therefore, the network was reduced by superimposing a square pattern over the monitored area and selecting one well per square block in a stratified pattern. The methodology was tested using the chloride data collected from 1972–2000 from 417 groundwater quality monitoring wells in the Gaza Strip. The number of the groundwater quality monitoring wells in the Gaza Strip was reduced by 53%, while there was 26% redundant information based on the minimum existing distance between wells. This methodology is meant to help monitor the groundwater quality (salinity) in the Gaza Strip. 相似文献
110.