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31.
It is a challenge to reduce the ever-increasing flow of waste. In Norway the systems for recycling of organic waste, paper, glass, metals, etc. differ between municipalities, both with regard to organizational and to technological structures. Our hypothesis is that people's attitudes and behaviour may differ with different systems of waste management. People's behaviour and attitudes regarding (organic) waste recycling were investigated in two municipalities with differing technical and organisational systems. Data came from interviews with municipal employees, questionnaires, focus groups and multi-criteria mapping. People seem to be better informed and more positive about organic waste recycling in one of the municipalities (MH, which has recycling of organic waste) than in the other (MS, which has no such recycling). The two municipalities had similar sets of important criteria for waste management (price, environmental friendliness, easy solutions, information). Many participants stated that they had learned from the group process, though only a few reported changed preferences. The institutional context seems to be important for people's behaviour and attitudes towards waste management. This implies that people's recycling behaviour does not only depend on technical and organisational aspects, but also on institutions. These are important messages for policy makers. On an individual basis, the different systems in the two municipalities seem to affect people's stated attitudes. These differences diminish when they are in a common setting where process and dialogue stimulate new thoughts and encourage people to act more altruistically.  相似文献   
32.
利用人工气候箱研究了抽穗期低温对杂交晚粳新组合宁67A/K1722开花量、包颈率及结实率的影响。结果表明:低温使抽穗速度明显变慢,开花量减少,包颈率呈现上升趋势,不同温度处理对结实率的影响不同,17℃与21℃处理间差异极显著,而19℃与21℃间差异不显著,不同时期处理及不同处理天数(3d,5d,7d和12d)间结实率差异不显著,表明该组合对抽穗期低温的耐受力较强,对抽穗期耐低温的鉴定指标问题进行了讨论。  相似文献   
33.
蓄水、调水、发电,扼制生态环境恶化   总被引:2,自引:0,他引:2  
蓄水是根本,调水是手段,发电是关键。植树造林和拦河筑坝建设水库电站以及沟渠塘蓄水,可以防止水土流失和水能浪费;调水可以解决横向和纵向水资源分布不平衡带来的问题;发电可以解决调水所需动力和全国缺电的问题。其经济效益约合2000亿元,而且还能扼制生态环境的恶化,减少每年46.6×104hm2土地的损失,缓解荆江大堤和黄河下游大堤越筑越高之危。  相似文献   
34.
污泥堆肥样品基质复杂,其中三氯生(TCS)和三氯卡班(TCC)的提取和净化过程操作烦琐、回收率低。通过对净化条件进行优化,建立了加速溶剂萃取-在线净化-液相色谱串联质谱法检测污泥堆肥样品中TCS和TCC的分析方法,并对上海某污水厂实际污泥堆肥样品中的TCS和TCC进行定量分析。结果表明,TCS和TCC的检出限分别为0.003和0.0002μg/g,加标回收率为90.3%~99.8%,相对标准偏差(RSD)为1.2%~8.5%(n=6)。该方法样品前处理时间短、回收率高、试剂使用量少,能够满足实际污泥堆肥样品中TCS和TCC的检测要求。  相似文献   
35.
接发列车作业事故在铁路运输事故中占有相当大的比重。为减少接车作业事故的发生,合理制定车站接车进路办理时的诊断时间是保证接车作业安全的关键。针对车站采用写实法查定时具有较大随意性的问题,提出采用人的认知可靠性(HCR)模型,根据人因失误概率计算接车作业诊断时间的方法,并在自动闭塞区段通过模拟机实验进行了验证。结果表明,HCR模型确定的诊断时间与人因失误之间的关系与写实法的测定数据具有良好的符合性;作业人员的训练水平对诊断时间有较大的影响;利用该模型,根据作业人员的训练水平与可接受的人因失误概率,可以确定接车进路办理的最佳诊断时间,或对写实法测定的诊断时间进行订正。  相似文献   
36.
建立行星传动起升机构电动机飞车的模型,计算电动机失电后各瞬间重物的速度、加速度,电动机的转速,从而分析事故的原因。  相似文献   
37.
Health research literature on quality and safety in recent years has pointed to a need to explore the characteristics of interdisciplinary team work unique to the health care sector and the particular organization. The literature also has identified a need for scientific models that explore and integrate existing findings concerning team dynamics. In this article, I attempt to address these concerns by developing and validating a scientific model for exploring safe work practices of interdisciplinary OR teams. Specifically, existing health research literature on quality and safety is reviewed to identify and incorporate various team-related aspects into dimensions of the proposed model. To further validate the model, I conduct an ethnographic study of safe work practices within an interdisciplinary OR setting. I find that safe work practices can be viewed as a product of the individual’s and team’s ability to draw on and combine explicit and tacit knowledge repertoires, which again is a product of the particular inner and outer structural conditions of a system. While the findings add their own unique distinctiveness to the scientific model, the findings also compare to the existing aspects and dimensions of the model. I conclude that the fit of the empirical data to the model improves the validity of the model, and also the potential application of the model in ethnographic research within different medical and/or team settings.  相似文献   
38.
为了解决平视显示器(Head Up Display,HUD)飞行中的注意资源分配问题,基于飞行模拟器,设计双作业飞行任务开展相关研究。基于事件相关电位(Event Related Potential,ERP)技术,选取行为绩效和P300成分为评价指标,采用oddball模式,在双作业飞行任务条件下开展实验研究。结果表明:随主任务难度的增加,主、辅任务的作业绩效均显著下降,被试者对HUD上异常信息的正确操作率降低,且反应时间延长;随主任务难度的增加,由辅任务所诱发的P300的波幅显著降低。在实验结果的基础上,最终提出了HUD状态下飞行员视觉注意资源分配机制。  相似文献   
39.
For conservation science to effectively inform management, research must focus on creating the scientific knowledge required to solve conservation problems. We identified research questions that, if answered, would increase the effectiveness of conservation and natural resource management practice and policy in Oceania's small‐island developing states. We asked conservation professionals from academia, governmental, and nongovernmental organizations across the region to propose such questions and then identify which were of high priority in an online survey. We compared the high‐priority questions with research questions identified globally and for other regions. Of 270 questions proposed by respondents, 38 were considered high priority, including: What are the highest priority areas for conservation in the face of increasing resource demand and climate change? How should marine protected areas be networked to account for connectivity and climate change? What are the most effective fisheries management policies that contribute to sustainable coral reef fisheries? High‐priority questions related to the particular challenges of undertaking conservation on small‐island developing states and the need for a research agenda that is responsive to the sociocultural context of Oceania. Research priorities for Oceania relative to elsewhere were broadly similar but differed in specific issues relevant to particular conservation contexts. These differences emphasize the importance of involving local practitioners in the identification of research priorities. Priorities were reasonably well aligned among sectoral groups. Only a few questions were widely considered answered, which may indicate a smaller‐than‐expected knowledge‐action gap. We believe these questions can be used to strengthen research collaborations between scientists and practitioners working to further conservation and natural resource management in this region.  相似文献   
40.
通过长斜井进入正洞施工的特长隧道,往往面临独头通风距离过长、工作面风量不足等问题,造成污染物难以在规定时间排出洞外。以衢宁铁路鹫峰山隧道风仓接力施工通风为依托,采用数值模拟方法研究了风仓长度、隔板长度及风机布置方式对轴流风机通风效率的影响,分析了原压入式通风和风仓接力通风洞内CO运移特性。结果表明,风仓长度从10 m增至25 m时,轴流风机通风效率大幅提高,风仓长度大于25 m时,对轴流风机通风效率的影响不大。设置中隔板会影响空气在风仓内的分流并产生较多旋流,从而降低风机通风效率;轴流风机远离斜井端对称布置,风仓内部风流的引流速度和引流范围最大,风流运动路径最优,通风效率最高。由于压入式通风受限于斜井断面尺寸及现场布置方式,当通风距离超过3 000 m后,无法满足洞内作业环境规定的条件。在正洞与斜井交叉部位设置密封的风仓,形成接力通风,能大幅度延长通风距离,提高通风效率,改善洞内空气质量。  相似文献   
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