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排序方式: 共有175条查询结果,搜索用时 15 毫秒
171.
Spiros Karakostas Dimitrios Economou 《International journal of geographical information science》2014,28(1):83-103
A new approach for treating multi-objective spatial optimization problems is introduced in this study, aiming at deriving the optimal spatial allocation of Wind Farms on a Greek Island (Lesvos). This work builds on the knowledge gained from numerous applications of multi-objective genetic algorithms, either for spatial planning purposes or for other engineering-related topics, by incorporating modified genetic operators and sophisticated planning criteria. Hence, a stand-alone genetic optimizer was developed that incorporates the controlled non-dominated sorting genetic algorithm-II (CNSGA-II), in which the user can model all planning criteria and constraints for every spatial entity to be allocated, and handle the genetic solver via a built-in computational framework that permits the analysis of large terrains. The presented paradigm provides interesting findings for the optimal development of renewable energy sources projects whose spatial allocation is governed by conflicting criteria and strict constraints. 相似文献
172.
Excessive sedimentation in mountain stream ecosystems is a critical environmental problem due to the clogging of streambeds by sediment particles within the hyporheic zone,with detrimental effects on fish spawning habitat.In this research,the effects of an array of boulders in regulating the intrusion of incoming sand within a gravel substrate were evaluated by performing detailed experiments in a laboratory flume.A unique experimental setup and two different sampling techniques were utilized for measuring the infiltrated sand within the gravel bed under two bed shear stress conditions(moderate vs.high).For comparison purposes,experiments were performed without and with the presence of partially submerged to the flow(protruding) boulders,which is typical for the average flow conditions found in mountain streams.Results indicated that sand infiltrated primarily in the upper part of the gravel bed creating a surface seal which hindered the penetration of sand particles deeper into the bed.An exponential decrease of the amount of the infiltrated sand within the hyporheic zone was observed in all experiments regardless of the presence of boulders.However,the presence of boulders promoted sediment intrusion of sand particles especially for the moderate applied bed shear stress condition,since the total amount of the infiltrated sand was found to be on average 44% greater whenboulders were present.The findings from this study can provide additional insight regarding the role of boulders on promoting downwelling of flow and sediment within the gravel substrate with potential effects on fish habitat. 相似文献
173.
Dimitrios Triantakonstantis Poulicos Prastacos Aikaterini Tsoukala 《Journal of the Indian Society of Remote Sensing》2014,42(3):601-610
Analysis of urban sprawl is an issue that has been continuously attracting attention in the planning and research community. Τhis paper presents the results of an analysis of the growth of the city of Rethymno during the 1997–2010 time period. Rethymno is a city in the island of Crete in Greece with population of about 35,000 people, in which developed land has expanded at a rate that is double the growth of the population during the study period. A qualitative analysis was first performed to identify growth patterns in the different parts of the city, how these are related to planning regulations and the extent of cohesiveness of the development. A logistic regression model was estimated using various variables influencing the expansion of the built up area. Variables such as slope, distance from main roads, distance from the University, distance from coastline, as well as variables describing the proximity to other developed areas were used as independent variables in the logistic regressions. Planning constraints with respect zoning were also considered. The accuracy/goodness of fit of the simulation results were also tested using Receiver Operating Characteristic (ROC) curve. The results revealed high (performance) accuracy, which can support the applicability of the proposed method in urban sprawl modeling. Once the equations were estimated they were applied using data from 2010 to identify future trends of urbanization. The methodology adopted in this study can result in a tool that can be of use to urban planning authorities in identifying areas of future urban growth and therefore, adopt zoning policies encouraging or discouraging growth in these areas according to the sustainability objectives of the local community. 相似文献
174.
Land disputes are among the primary issues that Land Administration Systems attempt to accommodate. They derive from a variety of purposes including law, history, culture, traditions, administration and local geographical characteristics. There is no uniform approach in addressing land disputes and each country implements different resolution techniques. Ecclesiastical and monastic institutions throughout the world are owners of immense real estate property to such an extent that can indeed affect land administration policies. Greece is in the limelight of international attention due to its economical crisis and actually under pressure to modernise its dysfunctional land policy framework and create a stable investment environment. Within this framework, this paper investigates issues hindering proper land administration in Greece through the examination of a the resolving process regarding a case study in the island of Crete; a complex legal land dispute between the Greek State, two ecclesiastical institutions, a monastery and a church, and squatters took place, lasting for nearly 40 years. In order to evaluate this procedure and its impact on the development of the disputed area, a variety of data sources were accumulated and processed through time-based analysis. In this direction, cadastral survey’s contribution was examined along with land use change analysis, indicating how uncertainties in securing property rights on land, result in illegalities and trespassing posing significant barriers in land administration and management in the course of time. Although old and ambiguous in describing land boundaries the monasterial documentation might be, it proved sufficient to prevail over other litigants claims; the monastery was even adjudicated more than twice the size of the area that was claiming. By this investigation process, the distinct role of ecclesiastical institutions in Greece regarding land acquisition and the defects and malfunctions within Greek Land Administration System are presented. The paper concludes with the authors’ suggestions for addressing similar real estate property situations concerning land disputes. 相似文献
175.
Moulas Evangelos Schenker Filippo Luca Burg Jean-Pierre Kostopoulos Dimitrios 《International Journal of Earth Sciences》2017,106(8):2667-2685
International Journal of Earth Sciences - The synmetamorphic nappe system of the Rhodope Metamorphic Complex has been deformed into dome-and-basin structures attributed to syn- to post-convergent... 相似文献