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1.
基于复杂系统建模的水管理政策研究进展 总被引:3,自引:0,他引:3
基于Agent的建模方法(ABSS)通过自下而上的方式,考察系统中主体的不同状态和行为特征、主体与环境的作用、主体之间的作用,来表征系统的宏观特征,是进行复杂社会环境系统分析和政策研究的重要手段,在水资源、水环境管理系统中得到了有效的应用。本文在大量文献调研的基础上,讨论了ABSS建模方法的基本原理、主要特征、系统构成、分类方法和开发工具等特征,总结了其供水系统发展、水资源分配和流域水资源管理、农业土地和水资源利用、居民用水行为、农业污染控制及人类活动的水环境影响等方面的应用,分析了其在研究内容、研究方法、研究结果等方面的发展趋势,讨论了利用该方法研究我国水资源管理和水污染控制政策的必要性和重要性。 相似文献
2.
Riviane R. Hora Claudie Doums Chantal Poteaux Renée Fénéron Jorge Valenzuela Jürgen Heinze Dominique Fresneau 《Behavioral ecology and sociobiology》2005,59(2):285-292
Social parasites exploit the worker force of colonies of other social insects to rear their own young. Social parasitism occurs in several Hymenoptera and is particularly common in several tribes of the ant subfamilies Myrmicinae and Formicinae. Here, we document the occurrence of miniaturized queens (microgynes) in colonies of Ectatomma tuberculatum, an ant belonging to the subfamily Ectatomminae. Behavioral observations and genetic analyses show that microgynes concentrate their reproductive efforts almost exclusively on the production of sexual offspring (microgynes and males), whereas the regular, large queens (macrogynes) produce workers in addition to sexuals. According to mitochondrial and nuclear markers, gene flow between microgynes and macrogynes is extremely limited. Whereas the co-occurrence of microgynes and macrogynes in the related species Ectatomma ruidum constitutes an intraspecific polymorphism associated with alternative dispersal tactics, microgynes found in colonies of E. tuberculatum appear to be a distinct species and to represent the first case of social parasitism in the poneromorph subfamilies of ants. 相似文献
3.
北京在历史上曾发生多次重大水灾,给人民生命财产、城市建设及社会安定带来了巨大影响。形成水灾的主要因素是永定河决口泛溢和区域雨涝。现从大量的历史文献中列举几个实例,来看水灾的严重程度及其影响后果。 相似文献
4.
本文阐述了高等院校教育技术的发展现状,分析了高等院校教育技术发展的特点,对高等院校教育技术的发展进行理性思考。认为高等院校应该在重视教育技术实践性和支持性研究的基础上,立足现实,更全面审视机构整合、教育信息化、信息资源库建设和教师培训这些热点问题。 相似文献
5.
Dr Claire Julian-Reynier Genevieve Macquart-Moulin Jean-Paul Moatti Anderson Loundou Yvette Aurran Françoise Chabal Ségolene Aymé 《黑龙江环境通报》1993,13(7):613-627
The objective of this study was to explore women's attitudes towards prenatal diagnosis of trisomy 21 and to examine some of the factors possibly responsible for these attitudes before implementing in real practice serological screening of pregnant women at risk for trisomy 21. We carried out a telephone survey on a representative sample of women who had recently had a normal livebirth delivery in the Marseille district in 1990. The participation rate was 80 per cent and the average age of the mothers was 28-9 years. Among the 514 women interviewed, 78 per cent stated that they would ask for an amniocentesis for a 1 per cent risk of trisomy 21 at their next pregnancy. When adjusting for confounding factors, the decision to have or not to have an amniocentesis was found to depend not only on the women's attitude towards induced abortion, but also on their understanding of the risk involved and on the social context (knowing a handicapped child, discussion with the father). It also depended on the women's age and on what they knew about amniocentesis from the medical point of view. The risk of miscarriage can influence a woman's choice but this objection was not found to affect the women's decisions significantly in our survey. The data showed the existence of a high potential demand for fetal karyotyping. 相似文献
6.
赵子维 《防灾技术高等专科学校学报》2005,7(4):119-121
本文分析了求知欲的由来及消退原因,“厌学症”的形成及治疗方案,试图唤起学生的求知欲,治疗他们的“厌学症”。 相似文献
7.
《环境科学学报(英文版)》2023,35(4):174-183
It is the key to control bio-derived dissolved organic matters (DOM) in order to reduce the effluent concentration of wastewater treatment, especially for waste leachate with high organic contaminants. In the present study, the anaerobic degradation of aerobically stabilized DOM was investigated with DOM substrate isolated through electrodialysis. The degradation of bio-derived DOM was confirmed by reduction of 15% of total organic carbon in 100 days. We characterized the molecular behavior of bio-derived DOM by coupling molecular and biological information analysis. Venn based Sankey diagram of mass features showed the transformation of bio-derived DOM mass features. Occurrence frequency analysis divided mass features into six categories so as to distinguish the fates of intermediate metabolites and persistent compounds. Reactivity continuum model and machine learning technologies realized the semi-quantitative determination on the kinetics of DOM mass features in the form of pseudo-first order, and confirmed the reduction of inert mass features. Furthermore, network analysis statistically establish relationship between DOM mass features and microbes to identify the active microbes that are able to utilize bio-derived DOM. This work confirmed the biological technology is still effective in controlling recalcitrant bio-derived DOM during wastewater treatment. 相似文献
8.
9.
论安全的社会属性 总被引:2,自引:3,他引:2
朱世伟 《中国安全科学学报》2003,13(9):14-19
安全不仅是一种物质技术的状态和条件 ,而且也是一种社会现象和过程。安全是社会性的人的生存和发展需要。这种需要渗透在社会结构的各个层面 ,表现为安全的生产力属性、利益关系属性、社会生活属性、文化属性和政治属性。笔者分析了上述 5种安全社会属性的产生、内容、演化及其相互联系 ,提出对安全社会原理的若干看法。研究有关安全的社会现象、过程和规律 ,有利于认识安全工作的社会地位、作用、目标和社会调整机制 ,形成安全技术进步的动力和保障条件 ,对于当前社会实践和学科建设有重要意义。 相似文献
10.
Tamim Younos Raymond de Leon Christine Lewicki 《Journal of the American Water Resources Association》2003,39(1):1-5
ABSTRACT: The objective of this article is to open a dialogue on integrating service‐learning into community based watershed management programs and to discuss opportunities and challenges that a service‐learning program presents to universities and communities. The article presents the concept and definition of service‐learning, and arguments concerning why institutions of higher education and university faculty and students should be involved with community based watershed management programs. The article describes a case study for developing a service‐learning program for watershed management at Virginia Tech and discusses lessons learned from the case study. The paper concluded that to make a service‐learning program sustainable, there should be a long term plan, regular and effective communication with the stakeholders, and some incentives for faculty and students for long term commitment to the community based watershed management programs. 相似文献