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701.
702.
A modified VIKOR method for multiple criteria analysis   总被引:2,自引:0,他引:2  
The VIKOR method was developed to solve multiple criteria decision making (MCDM) problems with conflicting or non-commensurable criteria. This method assumes that compromising is acceptable for conflicting resolution. Although the VIKOR method is a popular method applied in multi-criteria analysis (MCA), it has some problems when solving MCDM problems. This study discussed existing problems in the traditional VIKOR method. The objective of this study was to develop a modified VIKOR method to avoid numerical difficulties in solving problems by the traditional VIKOR method. Several synthetic experiments were designed and assessed to verify the improvement of solution efficiency of the modified VIKOR method in MCA.  相似文献   
703.
Abstract: Bushmeat is the main source of protein and the most important source of income for rural people in the Congo Basin, but intensive hunting of bushmeat species is also a major concern for conservationists. Although spatial heterogeneity in hunting effort and in prey populations at the landscape level plays a key role in the sustainability of hunted populations, the role of small‐scale heterogeneity within a village hunting territory in the sustainability of hunting has remained understudied. We built a spatially explicit multiagent model to capture the dynamics of a system in which hunters and preys interact within a village hunting territory. We examined the case of hunting of bay duikers (Cephalophus dorsalis) in the village of Ntsiété, northeastern Gabon. The impact of hunting on prey populations depended on the spatial heterogeneity of hunting and prey distribution at small scales within a hunting area. Within a village territory, the existence of areas hunted throughout the year, areas hunted only during certain seasons, and unhunted areas contributed to the sustainability of the system. Prey abundance and offtake per hunter were particularly sensitive to the frequency and length of hunting sessions and to the number of hunters sharing an area. Some biological parameters of the prey species, such as dispersal rate and territory size, determined their spatial distribution in a hunting area, which in turn influenced the sustainability of hunting. Detailed knowledge of species ecology and behavior, and of hunting practices are crucial to understanding the distribution of potential sinks and sources in space and time. Given the recognized failure of simple biological models to assess maximum sustainable yields, multiagent models provide an innovative path toward new approaches for the assessment of hunting sustainability, provided further research is conducted to increase knowledge of prey species’ and hunter behavior.  相似文献   
704.
Abstract

A process on crystallized precipitation of ammonium by adding magnesium salt and phosphate was carried out to improve C/N ratio in swine wastewater. After completion of crystallized precipitation of ammonium, an intermittent aeration process with aeration and non‐aeration periods alternated at interval of 1:1 hr day‐1 is used for the improved swine wastewater (T‐N/BOD=0.14: BOD=8200 mg/liter and T‐N=1166 mg/liter). The results obtained from the experiment show that the removal ratios of T‐N and NH4‐N are 91% and 99%, respectively. T‐P is not removed, while the removal ratio of PO4‐P is 60% as 3% of CaCl2 liquid is added. The results also indicate that dilution with water is effective to improve the removal of phosphorus even if raw swine wastewater contains high concentrations of T‐N, T‐P, BOD, and TOC.  相似文献   
705.
In situ remediation of aniline from soils and groundwater using biological and physical treatments was conducted at the BASF Corporation facility in Geismar, Louisiana. To mitigate the migration of aniline, remediate contaminated soil and groundwater, and determine concentrations, 24 immobilized microbe bioreactors were fixed in the subsoil, and a horizontal recovery well and 7 monitoring wells were installed. Soil and monitoring wells were sampled quarterly to assess bioplug impact on the aniline concentrations. The recovery well was sampled monthly to estimate the pounds of aniline removed from groundwater. Soil pH, composition, and microbial counts were used to estimate the fate and transport. Aniline levels were lowered significantly after remediation and total cancer risk was below levels for industrial sites, as established by State of Louisiana Risk Evaluation/Corrective Action Program guidelines. © 2010 Wiley Periodicals, Inc.  相似文献   
706.
Abstract

Carbofuran was applied over seeded rutabaga cv. York and residues (corrected for recovery) of carbofuran, 3‐hydroxy‐ and 3‐ketocarbofuran in the harvested roots averaged 0.15, 0.23 and 0.07 ppm in peel and 0.09, 0.14 and 0.05 ppm in pulp, respectively. Samples were extracted by hot acid digestion, partitioned in methylene chloride and cleaned up on Florisil. The 3‐hydroxy‐carbofuran was ethoxylated and the compounds were converted into their dinitrophenyl ethers and analysed by electron capture gas chromatography using 3% OV‐3 column.  相似文献   
707.
Abstract: Domestic dogs (Canis familiaris) and cats (Felis catus) are the most abundant mammalian carnivores worldwide. Given that domestic carnivores rely on human‐provided food, their densities are usually independent of prey densities. Nevertheless, underfed pets may need to hunt to meet their energetic and nutritional requirements. We explored the effects of different levels of care (provision of food) of dogs and cats on their predation rates on wild vertebrates in 2 areas of southern Chile. We interviewed cat and dog owners and analyzed prey remains in scats of pets to examine how domestic dogs and cats were managed and to gather information on the wild vertebrates killed and harassed by pets. We used logistic regression to examine the association between pet care and the frequency of wild vertebrate remains in scats. The probability of a dog preying on vertebrates was higher for poorly fed than for adequately fed dogs (odds ratio = 3.7) and for poorly fed than for adequately fed cats (odds ratio = 4.7). Domestic dogs and cats preyed on most endemic and threatened mammals present in the study sites. Our results provide support for the hypothesis that the less care domestic animals receive from owners the higher the probability those animals will prey on wild vertebrates.  相似文献   
708.
Since the inception of sustainable development (SD), there has been a somewhat ignored contradiction between paradigms that are ecosystem‐based and paradigms that are human‐based or purely economic. We suggest that this contradiction can be unified through a balance of the two. The Chinese Yin‐Yang philosophy is applied as a tool or approach to seeking balance between these ecocentric and anthropocentric paradigms. Priority education policy design for the merging of ecology and health are projected through an Ecohealth lens in response to increasing SD challenges and the intention of the international Ecohealth organization to contribute to SD goals. Meeting SD goals along the nexus of health and environment is further considered through early‐careerist cultural assessments and projections. The groups considered for their professional image of the future are: members of the Ecohealth Association Student Section and Chinese early‐careerists participating in a related conference. In response to SD goals, a problem‐based learning design is suggested as an education policy priority. Rather than approaching SD as a boolean concept, for example, by either focusing on ecosystem sustainability or economic development, we suggest education policy for programmes and curriculums that will help emerging professionals balance these paradigms, so as to best address national and global challenges.  相似文献   
709.
710.
京津冀生态环境协同保护立法的基本问题   总被引:2,自引:1,他引:1       下载免费PDF全文
京津冀生态环境的协同保护需要立法推动,因此,有必要制定《京津冀区域生态环境协同保护条例》或者《京津冀区域国土保护与整治条例》及配套的办法。在基本原则方面,可建立一体化保护、以环境质量管理为核心、功能与用途管制、共同但有区别责任等原则。在监管体制方面,可由国务院成立实体性的区域协同发展委员会。 在制度机制方面,可采取统一的环境规划、环境标准、总量控制、环评、监测与预警应急、生态补偿等措施。在法治架构方面,要建立一体化的环境市场、信息公开、公众参与、执法监管等体系。该立法的制定要符合以下标准:定位要精准,立法目的要明确;思路要清晰,措施的层次要分明;制度可实施,协同的措施要实际;原则要坚持,采取的手段可灵活;权利要公平,赋予的义务要均衡;实施可监督,失职的责任能追究。  相似文献   
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