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281.
Impediments to refractory recycling decision-making   总被引:1,自引:0,他引:1  
This paper focuses on organizational impediments to the successful implementation of industrial recycling programs. Even if a technologically viable and mutually beneficial solution were to exist, there are a number of organizational impediments that make it unlikely to succeed unless the benefits are very large and apparent. These impediments stem from the difficulty in identifying potential partners and involving the appropriate individuals within the firms that understand the technical requirements, value the strategic benefits and are receptive towards establishing the industrial recycling relationship. This dilemma applies to many industrial recycling opportunities, but solutions do exist. One way to avoid some of these obstacles is to use a middleman, or broker, who can play several crucial roles to establish the relationship. This paper describes the impediments and key broker roles, and provides a case study dealing with refractory recycling. It provides a case study that documents a recycling relationship between an aluminum-manufacturing firm that produces a large volume of spent refractories and a regional portland cement producer that is using the spent refractories as an alternative raw material source. This paper also provides a thorough literature search in the area of refractory recycling. Finally, the case study provides an opportunity for analysis and reflection on the implications of these findings to industrial firms, industrial societies and governmental agencies that seek to encourage successful recycling operations.  相似文献   
282.
为达到企业安全经济效益最大化的目标,运用系统动力学的方法对企业安全经济效益系统进行建模,并对其中的安全教育经济效益子系统进行仿真模拟。实验结果表明:改变系统中的影响因素,安全教育经济效益并没有立即发生变化,而存在一段“延迟阶段”。同时也证明了安全培训人员能力在安全教育经济效益系统中具有最大的影响效果。  相似文献   
283.
This study examined relationships between mentoring functions offered and transformational leadership as a mentor outcome and affective well‐being and organizational commitment as mutual outcomes for both mentors and protégés. For this examination, we conducted a longitudinal field study by using 111 matched reports from both mentors and protégés collected at three different points in time over seven months in nine Korean companies that administered a standardized formal mentoring program. Study results showed that mentoring functions assessed at Time 2 were positively associated with mentors' and protégés' post‐mentoring outcomes at Time 3 after controlling for pre‐mentoring initial levels of those outcomes at Time 1. Study findings also revealed that relative effects of mentoring on the mentor and protégé outcomes differed by the types of mentoring functions. We discuss the theoretical, practical, and methodological implications from these results. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
284.
从内在动力和外在诱因两个方面分析了管制员违章行为产生的根本原因,着重归纳了管制员有意违章的临界心理状态,揭示了违章行为的规律,并提出具体的防范控制措施.  相似文献   
285.
This commentary describes a gap in the qualitative and quantitative knowledge of the provision of benefits to humans from the intertidal ecosystems of the Mediterranean and offers a framework for quantification of the benefits provided by these systems. The identification of such benefits, understanding their spatial distribution and their subsequent quantification will be critical to the design of policy responses to future climate change, sea level rise and seawater acidification. A baseline understanding of the current state of ecosystem functions, as well as of the provision of related ecosystem services, is therefore needed. Further, researchers must strive to generate forecasts of the changes in these functions and services conditional on policy responses and the range of expectations for climate change.  相似文献   
286.
为了CDM项目的优化开发和大气污染物的协同控制,就国内CDM项目的污染物减排协同效应进行了分析.在统计其项目年减排量、总投资额以及协同减排系数的基础上,按不同项目类型(零排放的可再生能源、生物质、甲烷废气回收、燃料替代、煤层气回收、水泥原料替代、N2O分解消除以及节能和提高能效)和不同项目所在地(华中、华东、海南、华北、东北、西北以及华南)分析了项目的SO2、NOx和PM2.5协同减排量和投资减排收益.燃料替代、煤层气回收、节能提高能效类项目的投资减排收益高,华中和华东地区的生物质能源项目收益较高,而风电、水电类项目收益较低.  相似文献   
287.
Multiple paternity and offspring quality in tree swallows   总被引:1,自引:0,他引:1  
There is mounting evidence in a variety of taxa that females increase offspring quality by mating with multiple males, often resulting in multiple paternity. In birds, however, few studies have explicitly examined the benefits of mating with several different males; instead, the focus has been on whether or not extra-pair mating occurs, and its adaptive significance remains controversial. We examined the hypothesis that offspring quality, particularly immune response (phytohaemagglutinin assay) and growth, increases with the number of sires in broods of socially monogamous tree swallows (Tachycineta bicolor). We found one of the highest known levels of multiple paternity in birds (84% of nests with two or more extra-pair young had at least two extra-pair sires). Among nests with extra-pair young, the number and diversity of sires continued to increase linearly with the number of extra-pair young, so there was no evidence that some males monopolized paternity at high levels of extra-pair fertilization. Indeed, the number of sires was actually greater than expected in large broods, suggesting that some females might be seeking more mates. We found no effect of the number of sires on nestling immune response or growth. In mixed paternity broods, the immune response of extra-pair young did not differ from that of their within-pair half-siblings. However, among all broods, nestlings had a stronger immune response in nests with at least one extra-pair nestling than in nests with all within-pair nestlings. These results are not consistent with a good genes benefit of extra-pair mating, but they do suggest that there are environmental effects associated with extra-pair mating that increase nestling immune response. These environmental effects could produce indirect genetic effects on sexual selection if they are heritable. The extraordinarily high number of sires in this species highlights a relatively unexplored source of sexual selection in birds.  相似文献   
288.
油田企业在为国家提供丰富石油资源的同时也成为环境污染的大户。自推行清洁生产以来,我国油田企业在清洁生产审核过程、节能降耗、环境保护等方面取得了较好成绩。以某油田企业为例,根据清洁生产"节能、降耗、减污、增效"的思路,以企业能源、资源利用情况的分析为基础,提出和实施了多项清洁生产方案。通过注气闸门填料改进、洗车用水回收再利用、化验室增加回收罐回收污油等方案的实施,同比可节电:20.74×104kW.h/a、节气:52×104m3/a、节水:2.80×104m3/a、减少污油排放:1.50 t/a左右,实现了经济效益和环境效益的双赢。  相似文献   
289.
论矿产资源综合利用的系统功能与社会经济效益   总被引:5,自引:0,他引:5  
矿产资源综合利用体现了全面提高资源效益、环境效益、经济效益和社会效益辩证统一的系统功能。它拟应成为各国促进国民经济可持续协调发展的一项重大国策。矿业系统工程与价值工程相辅并用,是大力提高矿产综合利用的社会经济效益的最佳对策。  相似文献   
290.
ABSTRACT: The impact of degraded water quality on the value of seasonal homes adjacent to St. Albans Bay on Lake Champaign in northern Vermont is estimated using hedonic price functions. The Value of properties located adjacent to the bay are depressed by about 20 percent, or $4,500 on average, compared with similar nearby properties on the larger but cleaner lake. Water quality degradation resulted in decressed property values of approximately two million dollars in the area surrounding the Bay.  相似文献   
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