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651.
本文通过对KZ1床层、KZ2床层、KZ1和KZ2复合床层在不同床层厚度条件下,对氯化氰蒸气的动活性进行对比试验,并对试验结果进行分析,得出了后者并非前两者之和,而有了大幅提高的结论。 相似文献
652.
Communities around the world have increasingly come to demand more involvement in decision making for local mining projects, a greater share of benefits from them if they are to proceed, and assurances that mineral development will be conducted safely and responsibly. At the same time, Bridge (2004) notes full legal compliance with state environmental regulations has become an increasingly insufficient means of satisfying society's expectations with regards to mining issues. There is now a recognised need for mineral developers to gain an additional ‘social licence to operate’ (SLO) in order to avoid potentially costly conflict and exposure to business risks. However, there is a correspondingly limited amount of scholarship specifically focused on SLO. More particularly, there is a need for research that uncovers those factors that lead to the issuance (or non-issuance) of a SLO in the complex and changeable environments that often characterise mineral development. In an effort to identify key determinants of SLO outcomes in the mining industry, this paper presents a comparative case study analysis of four international mining operations: Red Dog Mine in Alaska, USA; Minto Mine in Yukon, Canada; the proposed Tambogrande Mine in Peru; and the Ok Tedi Mine in Papua New Guinea. The analysis that is presented also makes use of insights from supplementary key informant interviews conducted by the author and the emerging literature on mining and communities. Five lessons for earning a SLO emerged from this analysis: (1) context is key; (2) a social licence to operate is built on relationships; (3) sustainability is a dominant concern for communities; (4) local benefits provision and public participation play a crucial role; and (5) adaptability is needed to confront complexity. 相似文献
653.
Establishing “social licences to operate” with communities has become a significant corporate social responsibility agenda. The complex dynamics of these relationships can compound the impacts for communities when these contracts are not upheld. This article documents reflections from a rapid rural appraisal conducted in the Shire of Ravensthorpe in remote Western Australia after the Ravensthorpe Nickel Operation was “mothballed” 9 months into a projected 25-year lifespan. It captures how communication about the project and its time frames created a sense of consistency, predictability, certainty and trust – enabling social licence. The raising of hope and the emergence of mistrust underpin social, environmental and financial impacts of this event for the local community. Embedded in the theoretical dimensions of social licences, this case study highlights the problematic of social licences that engage with non-contractual stakeholders as partners in “booms” but have no legal responsibility towards them in times of “bust”. 相似文献
654.
ABSTRACTResidential care has increased in number of facilities and has grown in density in urban areas, yet it is disproportionately dispersed in cities and only beginning to meet the current long-term care need of older adults as an alternative to institutional and in-home care. California State Department of Social Services residential care facility data were linked with Los Angeles County census tract data to examine the spatial distribution of facilities through hot spot analysis of clusters of small and large facilities and zero-inflated negative binomial regression of census tract facility counts on older age and race groups, older disabled adults, and older adults in poverty in the area. The results show clusters of large facilities west of downtown Los Angeles and clusters of small facilities in the northern suburbs of the city in the San Fernando Valley. Increases in pre- and early-retired adults and older Hispanics in census tracts are associated with the greatest decreases in facility tract capacity in the area, whereas increases in the oldest old and older disabled adults are associated with the greatest increases. Understanding spatial disparities in residential care can help local agencies and developers plan and partner in more intentional and equitable development of facilities. The greatest opportunity for such development may lie in institutional tools for eldercare facility development such as the eldercare facility ordinance of Los Angeles and development of board and care facilities in residential zones of Los Angeles and other cities. 相似文献
655.
为开发高性能防护服以提升救援效率,基于人体试验,测量受试者穿戴灭火防护服、半封闭防化服、全封闭防化服以及基础服装(对照组)时静态条件下左右手握力值、疲劳度(RPE)和活动受限程度,通过方差分析、接受者操作特征(ROC)曲线图、相关性分析进行定量研究。研究结果表明:灭火防护服对消防员工效性能影响大于防化服,灭火防护服较对照组握力减小32%、RPE增大54%、活动受限程度增大35倍,且RPE和活动受限程度均与握力呈显著负相关(p<0.001)。研究结果可为消防员个体防护服装设计、测试、性能提升等提供理论支撑,也可为消防员生命安全保障研究提供基础数据。 相似文献
656.
资源型旅游地增长极限的理论模型 总被引:1,自引:0,他引:1
徐红罡 《中国人口.资源与环境》2006,16(5):35-40
在经济发展中,国内诸多地区都将旅游业发展作为支柱产业,但对其长期有效性却缺少理论和实证的探讨。一些落后地区虽然靠旅游发展获得第一桶金。走的是资源经济之路。但带动效益有限。本研究运用最新的发展理论,在对典型资源型旅游地作分析的基础上,建立了资源型旅游目的地发展的一般结构模型,并指出导致资源型旅游地发展的内部限制性因素。本研究希望更多的研究人员关注这一问题,从理论和实证上丰富和验证本文提出的理论假设。 相似文献
657.
为了对危险品的多式联运系统风险进行评估,首先在"人、机、管、环"4M理论的基础上,将多式联运中"转运"这一特殊流程考虑进去,以"人、机、管、环、转运"这5个因素作为决策问题中的属性;其次,采用犹豫直觉模糊语言集为决策者的初始决策矩阵赋值,并利用均值-标准差的汉明距离来衡量两个犹豫直觉模糊语言数之间的距离;然后,以危险品多式联运系统中的风险为标准,采用基于犹豫直觉模糊语言集的TOPSIS方法进行不同方案的决策。最后,以磷酸在宜昌-衢州之间的运输为案例,对4种常用运输方案进行风险评估,以综合评价指数进行对比。结果表明,在先水路后铁路、先水路后公路、先公路后铁路、先铁路后公路4种方案中,从宜昌到衢州之间先公路后铁路的运输方式所得综合评价值最高,应选择方案3。 相似文献
658.
Contingent valuation methods were used to derive an economic value for salmonid spawning habitat restoration. Anglers' willingness to pay for such restoration and farmers' willingness to accept compensation for lost productivity due to the restoration were investigated using questionnaire and face-to-face surveys, respectively. These elements were combined with the Wye Habitat Improvement Project (WHIP) budget into a cost-benefit analysis (CBA) based upon direct use values only. The CBA assumed that the WHIP will improve salmonid stock. Different levels of investment were considered and the CBA gave a positive net present value indicating an economically viable project and benefit-to-cost ratios greater than one for minor projects. However, the number of anglers using the Wye would need to double or triple in order to justify the full WHIP budget. Management of an environmental resource must consider users' and stakeholders' needs and opinions. It was found that anglers on the Wye value habitat/scenery in its own right and that this played an important part in the activity. Farmers' agreement regarding involvement in such projects was more likely to be determined by their political and ethical views than receiving an economic compensation. 相似文献
659.
Off-road vehicles increase soil erosion by reducing vegetation cover and other types of ground cover, and by changing the structure of soil. The investigation of the relationship between disturbance from off-road vehicles and the intensity of the activities that involve use of vehicles is essential for water and soil conservation and facility management. Models have been developed in a previous study to predict disturbance caused by off-road vehicles. However, the effect of data on model quality and model performance, and the appropriate structure of models have not been previously investigated. In order to improve the quality and performance of disturbance models, this study was designed to investigate the effects of model structure and data. The experiment considered and tested: (1) two measures of disturbance based on the Vegetation Cover Factor (C Factor) of the Revised Universal Soil Loss Equation (RUSLE) and Disturbance Intensity; (2) model structure using two modeling approaches; and (3) three subsets of data. The adjusted R-square and residuals from validation data are used to represent model quality and performance, respectively. Analysis of variance (ANOVA) is used to identify factors which have significant effects on model quality and performance. The results of the ANOVA show that subsets of data have significant effects on both model quality and performance for both measures of disturbance. The ANOVA also detected that the C Factor models have higher quality and performance than the Disturbance models. Although modeling approaches are not a significant factor based on the ANOVA tests, models containing interaction terms can increase the adjusted R-squares for nearly all tested conditions and the maximum improvement can reach 31%. 相似文献
660.
Increasing populations are causing an increase in food demands, and the area of cultivated land expands every year. Inappropriate land transition from ecology to production results in the constant decline of the ecological security level and influences the regional sustainable development. Adjusting unreasonable land use mode and reconstructing natural land cover are important ways to maintain and improve the ecological environment. Also reclaiming farmland as areas for forests and grasslands (FRFG) is another way. Successful implementation of FRFG in China is the result of comprehensive effect of the multi-scales driving forces. This paper analyses the driving forces of FRFG in China on a national (country) -regional (province) - local (county) - household (farmer) level scale, and the results are: driving forces at the national scale include ecological and food security and the western development of China; at the regional scale, ecological and economic benefits become the main factors to influence the dimension of FRFG under the same policy. The driving forces can be divided into 6 types: industrial structure adjustment, water source protection, flood prevention, the Three-Gorge Project protection, reduction of the amount of sediment flowing into the Yellow River and wind erosion desertification prevention. The driving forces at the local scale can be divided into 12 types with developing leading industries, increasing farmers' income and improving agricultural production conditions as the main types; at the household scale, the national policy meeting farmers' demands and the optimization of individual interests are all driving forces. 相似文献