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231.
In this paper we report the results of a field study conducted for the EU project HASTE, in which the effect of IVIS task difficulty on driving performance was assessed by three concurrent methods. These included objective vehicle-related measures, subjective ratings from drivers and expert observers’ evaluations. Results showed that all three techniques were sensitive to detecting the effect of IVIS task difficulty on driving performance. As well as demonstrating a promising technique for measuring the effect of varying levels of visual spatial IVIS task on driving performance, this study highlights the value of subjective ratings and observer evaluation in assessing the effect of IVIS on driving performance.  相似文献   
232.
Abstract

A three-year study over the Bai, Jingpo and Huayaodai communities in Yunnan Province reveals that the community development is significantly influenced in various ways by such cultural factors as the concepts of development; concepts and traditions of inter-community relationships, consumption, marriage and gender; patterns of decision-making and production, resource and income allocation; as well as the role of information dissemination systems, religion and ritual. Based on the analysis over the interactive relevance between each factor and community development, some strategies and methods for dealing with such a cultural relevance in development projects are recommended.  相似文献   
233.
化工厂排放SO2对周围植物的影响   总被引:6,自引:0,他引:6  
赖宝华 《化工环保》1996,16(4):230-234
对某厂区及常年盛行风下风向地区植物受SO2危害情况进行了调查,并测定了部分植物叶片中的硫含量。从植物叶片中的硫含量可间接地判断大气被SO2污染的程度及植物对SO2吸收与抵抗能力的强弱。  相似文献   
234.
Confined flow toward a single well of finite radius in an extensive aquifer of uniform transmissibility is studied under the assumption of time-dependent drawdown. Three particular cases are considered: (a) linear drawdown (including constant drawdown); (b) exponential drawdown; (c) periodic (sinusoidal) drawdown. The differential equation governing unsteady axial symmetric flow toward a single well in a confined aquifer is solved for the three different situations by the use of the Laplace transform method. The resulting expressions are integrated by adapting a modified Gemant scheme. General computer programs have been developed and operated for several combinations of characteristics. The results are plotted to show the effect of time dependent drawdown on the variation of the well discharge and the piezometric head distribution.  相似文献   
235.
The sustainable management of coastal natural resources inevitably involves identifying stakeholder conflicts and developing planning processes that prevent these conflicts from becoming intractable disputes. This study links environmental conflict to specific areas within a large ecological system. Specifically, we use Geographic Information Systems (GIS) to map potentially competing stakeholder values associated with establishing protected areas in Matagorda Bay, Texas. By overlaying multiple values associated with a range of stakeholders across space, we are able to identify hotspots of potential conflict as well as areas of opportunity for maximizing joint gains. Mapping stakeholder conflict is an approach to proactively locate potential controversy in response to a specific environmental management proposal and guide decision makers in crafting planning processes that mitigate the possibility of intractable disputes and facilitate the implementation of sustainable coastal policies. Results indicate that under different management scenarios, protected area proposals will generate more conflict in specific areas. Most notably, regulated uses would produce the greatest degree of conflict on or near shore, particularly at the mouth of the Colorado River. Additionally, of all the management scenarios evaluated, the prohibition of coastal structural development would generate the overall highest level of conflict within the Bay. Based on the results, we discuss the policy implications for environmental managers and provide guidance for future research on location-based conflict management within the coastal margin.  相似文献   
236.
从溧  王媛 《四川环境》1994,13(1):26-29
本文介绍了在环境监测中,经试验研究,确定的用阳极溶出伏安法,连续分析环境样品中重金属Cu,Pb,Cd的最佳条件,即用悬汞电极做工作电极,用0.1M离氯酸做支持电解质,纯氮除氧。当PH值取2-7,富集电位数-1.1~-1.2V时,不但可连续测定一定浓度范围的重金属Cd,Pb,CU;而且方法灵敏度高,精密良好,线性相关关系可达0.9990,回收率达85-115%,获得了良好的分析效果。  相似文献   
237.
长江南通段江面风的观测分析   总被引:4,自引:0,他引:4  
通过在长江南通段江面、江岸建立风观测站,并在江岸建设80m高的风梯度观测塔,与邻近气象站开展了较长时间的风同步观测,获得了实地观测数据.利用同步风观测数据进行对比分析,揭示出长江南通段江面风的观测事实,并利用风梯度观测资料,分析给出了风随高度的变化规律.在此基础上,结合邻近气象站长年的风观测资料,推算了该处的设计基本风速及其他工程设计风参数.分析表明,该处江面风况明显有别于邻近气象站,风参数计算结果也明显高于风工程理论推算值.  相似文献   
238.
耗散结构理论在矿井通风系统优化中的应用   总被引:2,自引:0,他引:2  
利用耗散结构理论,以系统的影响参数作为切入点,对矿井通风系统的形成过程、系统平衡等进行描述,据此得出了一些探讨性结沦,这些有助于矿井通风系统优化与控制的计算机模拟。  相似文献   
239.
通过对槽上防尘系统基础电气化、控制阀门、料位计、下料漏嘴及防尘皮带的改造,使设备作业率达到98%,防尘效果提高到国家标准的3倍。  相似文献   
240.
降雨径流污染主要是通过雨水的冲刷和淋溶作用携带污染物进入受纳水体,造成水体黑臭化或富营养化.了解和掌握降雨径流污染特征是有效控制径流污染的前提.全面分析廊坊市城区降雨径流污染时空分布特征和各污染物相关关系,通过在市区设置14个采样点采集了7次降雨径流样品,分析了样品中的悬浮固体(SS)、化学需氧量(COD)、N、P、粪...  相似文献   
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