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1.
介绍了金山店铁矿通风系统多级站和机站设计;阐述了该项目的施工,检测及通风效果评估情况;对安全生产提出了全面,系统的建议。  相似文献   
2.
以人为因素为中心的航空安全多级模糊综合评价   总被引:2,自引:2,他引:2  
在航空安全中,根据SHEL模型,以人为因素为中心,列出影响航空安全的一级和二级指标进行多级模糊综合评价,得出各指标对航空安全的影响权重,从而采取相应措施,即加强组织内的横向纵向沟通交流,加大机务方面的培训力度,严格按照标准操作程序,形成公正合理、积极向上的企业文化,以提高航空安全.  相似文献   
3.
A new framework for analysing subnational policymaking is applied to climate governance in the ‘twin towns’ of Newcastle upon Tyne and Gelsenkirchen. Low levels of resource interdependence between central and local government in England mean that Newcastle Council has to rely heavily on other horizontal actors to achieve its climate objectives. In contrast, Gelsenkirchen Council receives substantial support from higher tiers of government, which gives it greater control over policymaking within the locality. Greater independence between tiers of government can make it more difficult for subnational bodies to adopt the kind of ambitious policies that may be necessary to combat wicked and/or significant policy challenges such as climate change. Instead, interdependent ‘joint-decision’ systems, which facilitate mutual support across tiers of government, may be better equipped to ensure that subnational public bodies have the capacity to act appropriately.  相似文献   
4.
Estimating the effect of agricultural conservation practices on reducing nutrient loss using observational data can be confounded by factors such as differing crop types and management practices. As we may not have the full knowledge of these confounding factors, conventional statistical meta‐analysis methods can be misleading. We discuss the use of two statistical causal analysis methods for quantifying the effects of water and soil conservation practices in reducing P loss from agricultural fields. With the propensity score method, a subset of data was used to form a treatment group and a control group with similar distributions of confounding factors. With the multilevel modeling method, data were stratified based on important confounding factors, and the conservation practice effect was evaluated for each stratum. Both methods resulted in similar estimates of the conservation practice effect (total P load reduction avg. ~70%). In addition, both methods show evidence of conservation practices reducing the incremental increase in total P export per unit increase in fertilizer application. These results are presented as examples of the types of outcomes provided by statistical causal analyses, not to provide definitive estimates of P loss reduction. The enhanced meta‐analysis methods presented within are applicable for improved assessment of agricultural practices and their effects and can be used for providing realistic parameter values for watershed‐scale modeling.  相似文献   
5.
为提高乳品工业废水生物处理的去污脱氮能力,以新型螺旋状纤维填料作为载体,采用多级氧化槽内不同种类微生物形成的食物链系统(food chain reactor),详细考察了不同水力停留时间COD、TN、NH4-N、TP等的去除率及其去除机理,并对污泥减量化效果进行了初步探讨.结果表明,当进水COD为842~1 843  mg/L、TN为36.3~92.2  mg/L、NH4-N为30.1~52.1  mg/L,HRT=6 h时,系统COD的平均去除率达到93.3%;TN和NH+4-N的去除效果显著,其平均去除率分别达到73.3%和80.7%,出水COD、TN、NH+4-N平均值分别为79.4 mg/L、9.6  mg/L、6.1 mg/L,均低于《污水综合排放标准》(GB 8978-2002)的一级标准.该系统不仅具有较高的去污脱氮效果,而且产生的剩余污泥量极少,其污泥产率的平均值为7.7%.该系统运行费用低,操作管理方便,长期运行稳定,可应用于城市污水、中高浓度有机废水(如餐厅污水、食品工业废水)等的处理.  相似文献   
6.
Interpersonal trust is associated with a range of adaptive outcomes, including knowledge sharing. However, to date, our knowledge of antecedents and consequences of employees feeling trusted by supervisors in organizations remains limited. On the basis of a multisource, multiwave field study among 956 employees from 5 Norwegian organizations, we examined the predictive roles of perceived mastery climate and employee felt trust for employees' knowledge sharing. Drawing on the achievement goal theory, we develop and test a model to demonstrate that when employees perceive a mastery climate, they are more likely to feel trusted by their supervisors at both the individual and group levels. Moreover, the relationship between employees' perceptions of a mastery climate and supervisor‐rated knowledge sharing is mediated by perceptions of being trusted by the supervisor. Theoretical contributions and practical implications of our findings are discussed.  相似文献   
7.
Abstract: Multilevel or hierarchical models have been applied for a number of years in the social sciences but only relatively recently in the environmental sciences. These models can be developed in either a frequentist or Bayesian context and have similarities to other methods such as empirical Bayes analysis and random coefficients regression. In essence, multilevel models take advantage of the hierarchical structure that exists in many multivariate datasets; for example, water quality measurements may be taken from individual lakes, lakes are located in various climatic zones, lakes may be natural or man‐made, and so on. The groups, or levels, may effectively yield different responses or behaviors (e.g., nutrient load response in lakes) that often make retaining group membership more effective when developing a predictive model than when working with either all of the data together or working separately with the individuals. Here, we develop a multilevel model of the impact of farm level best management practices (BMPs) on phosphorus runoff. The result of this research is a model with parameters which vary with key practice categories and thus may be used to evaluate the effectiveness of these practices on phosphorus runoff. For example, it was found that the effect of fertilizer application rate on farm‐scale phosphorus loss is a function of the application method, the hydrologic soil group, and the land use (crop type). Further, results indicate that the most effective method for controlling fertilizer loss is through soil injection. In summary, the resultant multilevel model can be used to estimate phosphorus loss from farms and hence serve as a useful tool for BMP selection.  相似文献   
8.
Why social values cannot be changed for the sake of conservation   总被引:1,自引:0,他引:1       下载免费PDF全文
The hope for creating widespread change in social values has endured among conservation professionals since early calls by Aldo Leopold for a “land ethic.” However, there has been little serious attention in conservation to the fields of investigation that address values, how they are formed, and how they change. We introduce a social–ecological systems conceptual approach in which values are seen not only as motivational goals people hold but also as ideas that are deeply embedded in society's material culture, collective behaviors, traditions, and institutions. Values define and bind groups, organizations, and societies; serve an adaptive role; and are typically stable across generations. When abrupt value changes occur, they are in response to substantial alterations in the social–ecological context. Such changes build on prior value structures and do not result in complete replacement. Given this understanding of values, we conclude that deliberate efforts to orchestrate value shifts for conservation are unlikely to be effective. Instead, there is an urgent need for research on values with a multilevel and dynamic view that can inform innovative conservation strategies for working within existing value structures. New directions facilitated by a systems approach will enhance understanding of the role values play in shaping conservation challenges and improve management of the human component of conservation.  相似文献   
9.
ABSTRACT: A nonlinear multilevel transportation model is developed to study large-scale allocations in a water resources system. The model uses a modified transportation matrix formulated with nonlinear cost functions as the basic subregional model and the goal coordination method for multilevel decomposition and optimization of the overall regional system. The model is applied to projected water requirements for Salt Lake County in 1985. Sources of water supply - surface water, ground water, import water, and reuse of reclaimed wastewater on a restricted basis - are available to satisfy water requirements for municipal, industrial, and agricultural sectors in four subregions. The conjugate gradient projection method is used to optimize the first level subregional models having cost functions of the form of C = aXb, and the second level problem is solved using the conjugate gradient method.  相似文献   
10.
采用一种新型的多级A/O膜生物反应器处理污水,对该工艺的污泥活性进行了研究。结果表明,VSS/SS在实验过程中呈较弱的下降趋势,多级A/O池曝气室污泥比硝化速率逐室下降,但各缺氧室污泥比反硝化速率基本一致;污泥释磷、聚磷过程在30 min和1 h内基本完成,反硝化聚磷试验表明污泥中存在DPB的富集,反硝化作用是反硝化细菌与DPB共同作用的结果。  相似文献   
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