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11.
交际法已经发展成为一种世界规模的外语教学理论和教学方法,成为当今世界各国外语教学界普遍承认和接受的基本原则.通过对交际教学法的进一步研究分析,叙述了什么是交际教学法,阐述了运用交际教学法组织大学英语教学的模式和交际教学法在大学英语教学中的运用,指出教师应充分运用交际教学法的基本原理更好地来提高中国英语教学水平. 相似文献
12.
Zagonari F 《Journal of environmental management》2008,88(4):796-804
In this paper, a dynamic model is developed in which coastal quality can be improved, restored, or maintained by two distinct user groups; this is done by identifying a context that ensures an increase (or a greater increase) in coastal quality in terms of specific features that characterise the user groups. The results demonstrate that integrated coastal management is always better than non-integrated management. Moreover, when there is a low degree of interest in maintaining the coastal use over time, only integrated community-based (CB) coastal management will increase the coastal quality. Even when the interest in maintaining the coastal use over time is high, an integrated CB approach is preferred if the willingness to pay for coastal improvements is great and the marginal inefficiency of investments in coastal improvements is low, because the coastal quality improves to a greater extent; if not, only an integrated top-down (TD) approach to coastal management will increase the coastal quality. These results suggest that developing countries should always adopt a CB approach; in contrast, developed countries should adopt a CB approach where local stakeholders attach direct values to the coastal quality, and adopt a TD approach where the general population attaches indirect (option or existence) values to coastal quality. 相似文献
13.
John Troiano Craig Nordmark Terrell Barry Bruce Johnson 《Environmental monitoring and assessment》1997,45(3):301-319
A well sampling study was conducted to evaluate anempirical approach to classifying areasof land in California as vulnerable to ground watercontamination by pesticides (Troiano et al., 1994). Wells were sampled from sections of land that had noprevious detections of pesticideresidues. The sections had been classified into vulnerablesoil clusters or into a not-classified groupusing a procedure based on Principal Components Analysis(PCA). Grape, citrus, and olive growingareas of Fresno and Tulare Counties were targeted, areas wherepre-emergence herbicide residues hadbeen detected in well water. Overall, herbicide residues weredetected in 75 of 176 sampled wells, ahigh frequency of detection in relation to results fromprevious targeted well sampling studies. Sinceresidues were also detected in the not-classified group, theclassification procedure was modified usingan approach based on Canonical Variates Analysis (CVA). Moresections were classified intovulnerable soil clusters with the CVA approach than with thePCA method. Data from two otherexplanatory variables, depth to ground water and amount ofpesticide used per section, were includedto illustrate how additional information can be incorporatedinto this approach of identifying vulnerable areas. 相似文献
14.
欧日中实施GHS政策的对比和思考 总被引:2,自引:0,他引:2
通过研究欧盟、日本和我国实施全球化学品统一分类和标签制度(GHS)的基本情况,并从实施GHS的框架体系、实施GHS的时间节点、GHS的危险类别和GHS危险类别的判定,4个方面对欧盟、日本和我国实施GHS的现状进行重点研究。通过对比分析得出我国当前实施GHS主要存在4个方面的问题,即缺乏实施GHS的综合法律、实施GHS缓冲期的设置存在问题、缺乏开展GHS分类的配套指南、没有合理的运用"积木原则"。结合我国的实际情况提出3个方面的建议:适时推动我国GHS法律法规体系的建设、在各部门的协作下编制我国的GHS分类指南、合理的运用"积木原则"。通过分析表明:欧盟实施的GHS政策最为完善且力度最强,日本次之;由于充分利用"积木原则",欧盟的GHS类别与日中存在一定的差异;欧日中在数据运用和GHS危险判定原则上存在差异。 相似文献
15.
尉春艳 《中国环境管理干部学院学报》2012,(4):71-74
在市场营销专业教学中,通过借鉴CDIO教学理念,建立三系统、四模块教学体系,制定基于项目的"做中学"的教学内容,采用行为导向的六步教学法引导学生主动学习,通过多元化方式进行评价,加强机制建设与教学团队建设。 相似文献
16.
Prioritization for Conservation of Northern European Cattle Breeds Based on Analysis of Microsatellite Data 总被引:2,自引:0,他引:2
17.
The Atlantic Coastal Action Program (ACAP) is a unique, community-based program initiated by Environment Canada in 1991 to help Atlantic Canadians restore and sustain watersheds and adjacent coastal areas. ACAP is the eastem-most Environment Canada Ecosystem Initiative. The ACAP family is currently made up of 14 ecosystem-based organizations in the four Atlantic provinces. Each one of these non-profit organizations operates independently, but is formally linked under the umbrella of ACAP to represent a force stronger than the individual parts. In Environment Canada's experience, the program consistently demonstrates the value of a community-based approach and produces results on an ecosystem basis. This paper will examine some of the impacts of ACAP in terms of economics, credible community science, and environmental results which most often align with Environment Canada's objectives. It will explore the influences of the community-based approach to environmental management on multiple scales (local, regional, etc.). Through examples, the paper will demonstrate the effectiveness of ACAP in influencing some of the policies, programs and attitudes of various levels of government and industry in the region, as well as describe how the community-based model has been exported internationally. The paper will conclude with a discussion on a planned path forward for ACAP. 相似文献
18.
H. T. Schreuder R. Czaplewski R. G. Bailey 《Environmental monitoring and assessment》1999,56(3):269-291
A forest ecological inventory and monitoring system combining information derived from maps and samples is proposed based on ecosystem regions (Bailey, 1994). The system extends the design of the USDA Forest Service Region 6 Inventory and Monitoring System (R6IMS) in the Pacific Northwest of the United States. The key uses of the information are briefly discussed and expected results are illustrated with examples. The system is flexible, allowing regions based on ecological considerations to be modified. Sampling intensities that are affordable are likely to be insufficient to provide meaningful estimates for key parameters relating to rare and endangered species, watersheds, and other ecological units. Methods are proposed for collecting additional information in follow-up surveys and combining it with relevant information obtained in R6IMS. Near-continuous information on weather and possible pollution variables recorded by instruments at sampling sites is needed to develop meaningful models to understand what is happening in the ecoregions. R6IMS and the proposed additions constitute a dynamic system which will be modified further as data are analyzed. 相似文献
19.
以太湖的表层沉积物为研究对象,运用相平衡分配法(EqP)探讨了沉积物中4种重金属(Cu, Pb, Zn, Cd)的沉积物质量基准(CSQC)值;根据美国国家环境保护局(US EPA)基于水生生物对重金属的最终慢性毒理水平的淡水水质基准,制定了太湖4种重金属(Cu, Pb, Zn,和Cd)的沉积物质量基准值分别为145.2,308.72,293.01,0.46mg/kg.以此CSQC为参比值,参考潜在生态危害指数法对各元素赋予不同的权重值,运用综合污染指数法对太湖沉积物重金属的环境质量进行评价,结果显示,2010年8~9月太湖沉积物质量基本为良.这一结果与沉积物重金属总量分析结果一致. 相似文献
20.
Sensitivity analysis of the two dimensional application of the Generic Ecological Model (GEM) to algal bloom prediction in the North Sea 总被引:2,自引:0,他引:2
Harmful algae can cause damage to co-existing organisms, tourism and farmers. Accurate predictions of algal future composition and abundance as well as when and where algal blooms may occur could help early warning and mitigating. The Generic Ecological Model is an instrument that can be applied to any water system (fresh, transitional or coastal) to calculate the primary production, chlorophyll-a concentration and phytoplankton species composition. It consists of physical, chemical and ecological model components which are coupled together to build one generic and flexible modelling tool. In this paper the model has been analyzed to assess sensitivity of the simulated chlorophyll-a concentration to a subset of ecologically significant input factors. Only a small number of approaches could be considered as suitable for several reasons including the model complexity, engagement of numerous interacting parameters and relatively long time of a single simulation. Thus, sensitivity analysis has been carried out with the use of the Morris method and later enriched by the computation of the correlation ratios of the selected parameters on the model response at more than a few locations in the modelled area. The obtained results are in agreement with expert knowledge of the ecological processes in the North Sea and correspond well with local characteristics. 相似文献