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131.
海洋生态调控智能决策支持系统(IDSSMER)是建立在海洋生态系统动力学原理与控制论方法基础上,以计算机科学技术为主,综合系统科学、管理科学以及海洋生态学的理论和方法的人机交互系统,旨在为决策者在协调资源与环境的生态关系、探索海洋生物资源可持续发展的生态调控对策与可行途径等方面提供一个良好的支持工具。给出IDSSMER的数据库系统、模型库系统、方法库系统及知识库系统,具有信息服务、科学计算和决策咨询的功能,这种四库三功能结构,以实规定量计算与定性推理有机地结合。最后构迄了基于数据库的知识库以及采用双向推理策略的海洋生态知识库系统结构。  相似文献   
132.
我国规模化畜禽养殖业存在的环境问题与防治对策   总被引:67,自引:0,他引:67  
李远 《上海环境科学》2002,21(10):597-599
近年来,由于我国畜禽养殖业的养殖规模、养殖方式和分布区域发生了巨大的变化,它所带来的环境污染问题总体呈现出总量增加、程度加剧和范围扩大的趋势,归纳了我国规模化畜禽养殖业环境污染的特点,从生产、技术、政策和管理上分析了影响我国畜禽养殖业环境污染的主要因素,并提出了污染防治的对策建议,即借鉴发达国家畜禽养殖业的环境管理经验,以减量化、资源化、无害化及实用、廉价为原则,合理规划、防治结合,努力探索一条具有中国特色的规模化畜禽养殖污染防治道路。  相似文献   
133.
大伙房水库上游禽畜业污染现状及其防治对策   总被引:1,自引:0,他引:1  
为了保护大伙房水库 ,控制水库上游禽畜养殖业污染 ,对禽畜养殖业污染现状进行了调查 ,估算了禽畜粪尿的流失量。结果表明 ,一头猪日排泄粪尿量约是人排粪尿的 5倍。水库上游禽畜养殖业污染负荷已超过水库上游生活污水的污染负荷 ,成为了水库上游地区主要的有机物污染源。对此 ,提出了控制禽畜业污染的对策和建议。  相似文献   
134.
Variations in land requirements for meat production   总被引:2,自引:0,他引:2  
Production of meat requires substantial amounts of feed grains which in turn require vast amounts of land. Future population growth and increase in consumption will raise the demand for meat and with it the land required for meat production. This paper analyses the various factors that affect land requirements for meat production. Meat production by Dutch broilers, pigs and beef cattle on their current feeds are compared and options for change are evaluated with respect to their nutritional needs. Differences in land requirements of a factor of 3 were found between different agricultural production systems and feeds as well as between types of livestock. It is shown that broilers have the lowest land requirement while beef cattle have the highest. The variation in feed crop yields between agricultural systems is discussed. It is concluded that due to the large variation within the system there is potential for reduction in the land requirements for meat production.  相似文献   
135.
智能型数字校园网的探讨   总被引:2,自引:0,他引:2  
随着计算机网络技术的发展,数字化校园网的建设已经进入成熟的后期阶段,但是纵观现有的各高校的数字化校园网络,其智能型的数字校园网还处于初级发展阶段.因此。通过基于智能型的数字校园网从概念、实现目标、规划与设计等方面进行了初步探讨研究.图1,参5.  相似文献   
136.
安全管理决策支持系统及其最新进展   总被引:1,自引:0,他引:1  
安全管理是企业管理的重要组成部分,是实现安全生产的有力保证.决策支持系统是实现安全管理定性与定量分析有机结合的有效手段.该文结合安全管理,简要阐述了决策支持系统产生的背景、内容和发展趋势.介绍了作者在企业安全管理决策支持系统研制方面的主要结果和进一步工作的构想.  相似文献   
137.
Can animals, and especially cattle, be the subject ofmoral concern? Should we care about their well-being?Two competing ethical theories have addressed suchissues so far. A utilitarian theory which, inBentham's wake, extends moral consideration to everysentient being, and a theory of the rights orinterests of animals which follows Feinberg'sconceptions. This includes various positions rangingfrom the most radical (about animal liberation) tomore moderate ones (concerned with the well-being ofanimals). Notwithstanding their diversity, theseconceptions share some common flaws. First, as anextension of primarily anthropocentric theories (aboututility or rights) they still participate in the flawsof the original setting. Second, extending them tonon-human beings raises the problem of the borderwhich is to be drawn between what can be included inthe purview of moral consideration and what is leftoutside. Third, such theories are not able to distinguishbetween an ethics of wildlife and an ethics ofdomestic life, which too often leads to preposterousstatements. We would like to argue (i) that we should distinguishbetween environmental ethics (concerned withpopulations, species, biotic communities) and animalethics (where animals are taken into consideration individually);(ii) that individualist animal ethics are not relevantfor animal rearing; (iii) that animal rearing is a hierarchicalrelationship which rules are to be found in the fiction of a domesticcontract. Hence, we would like to construct a new conception ofthe ethics of the relation between men and the cattlethey breed based on the idea of a domestic contract.Our main assumption is Mary Midgleys's anthropologicalassumption, according to which human communities,since the Neolithic age, have always included variousanimals, so that relations of sociability have alwaysexisted between human beings and animals within thedomestic community (a mixed community). In order tospecify the hierarchical and non-egalitarian, butinclusive reciprocal obligations and relations insidesuch a community, we will elaborate on the notion ofa ``domestic contract'', an implicitly assumedidea traced back to Lucretius and whichwe will follow up to the physiocrats and Adam Smith.We will show that such an idea relies upon theassumption of communication between cattle farmer andanimals, of shared experience and exchanges betweenthe two parties. We will then show how modern factory,or battery animal farming, can be seen as unilaterallybreaking this domestic contract, forsaking ourduties towards domestic animals.  相似文献   
138.
139.
Introduction: Crashes involving roadway objects and animals can cause severe injuries and property damages and are a major concern for the traveling public, state transportation agencies, and the automotive industry. This project involved an in-depth investigation of such crashes based on the second Strategic Highway Research Program (SHRP 2) Naturalistic Driving Study (NDS) data including detailed information and videos about 2,689 events. Methods: The research team conducted a variety of logistic regression analyses, complemented by Support Vector Machine (SVM) analyses and detailed case studies. Results: The logistic regression results indicated that driver behavior/errors, involvement of secondary tasks, roadway characteristics, lighting condition, and pavement surface condition are among the factors that contributed significantly to the occurrence and/or increased severity outcomes of crashes involving roadway objects and animals. Among these factors, improper turning movements (odds ratio = 88), avoiding animal or other vehicle (odds ratio = 38), and reaching/moving object in vehicle (odds ratio = 29) particularly increased the odds of crash occurrence. Factors such as open country roadways, sign/signal violation, unfamiliar with roadway, fatigue/drowsiness, and speeding significantly increased the severity outcomes when such crashes occurred. The sensitivity analysis of the three SVM classifiers confirmed that driver behavior/errors, critical speed, struck object type, and reaction time were major factors affecting the occurrence and severity outcomes of events involving roadway objects and animals. Practical Applications: The study provides insights on risk factors influencing safety events involving roadway objects, including their occurrence and the severity outcomes. The findings allow researchers and traffic engineers to better understand the causes of such crashes and therefore develop more effective roadway- and vehicle- based countermeasures.  相似文献   
140.
In this paper, we describe how spatial on-line analytical processing (SOLAP), a specific category of business intelligence technology especially adapted to geospatial data, can help to improve the technological side of public participation GIS applications. Based on two simulated cases of realistic scenarios of a public audience, this paper aims at demonstrating the relevance of this SOLAP technology to support and improve the interactive access and analysis of multi-scale, multi-epoch geospatial information (and indirectly public involvement) for an environmental management PPGIS application.  相似文献   
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