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211.
Contemporary food supply chains are generating externalities with high economic and social costs, notably in public health terms through the rise in diet-related non-communicable disease. The UK State is developing policy strategies to tackle these public health problems alongside intergovernmental responses. However, the governance of food supply chains is conducted by, and across, both private and public spheres and within a multilevel framework. The realities of contemporary food governance are that private interests are key drivers of food supply chains and have institutionalized a great deal of standards-setting and quality, notably from their locations in the downstream and midstream sectors. The UK State is designing some downstream and some midstream interventions to ameliorate the public health impacts of current food consumption patterns in England. The UK State has not addressed upstream interventions towards public health diet at the primary food production and processing stages, although traditionally it has shaped agricultural policy. Within the realities of contemporary multilevel governance, the UK State must act within the contexts set by the international regimes of the Common Agricultural Policy and the World Trade Organization agreements, notably on agriculture. The potential for further upstream agricultural policy reform is considered as part of a wider policy approach to address the public health externalities issuing from contemporary food supply chains within this multilevel governance context.  相似文献   
212.
This article attempts to analyse the social interface between formal institutions and local fishing communities along the Pamba‐Achankovil River Basin in Kerala, India. It examines primarily the nature of the relationship between state agencies and traditional fishing communities in the context of (i) enforcing certain formal regulations of resource use and (ii) implementing resource enhancement programmes. The article also analyses the nature of social interfaces that emerge when local level formal organizations, such as cooperatives and gram panchayats, take up resource management or community welfare schemes on behalf of the traditional fisherfolk in the study region. Social interfaces can be understood in terms of social processes, such as cooperation, accommodation and conflicts between various actors involved in fisheries management. The article is based on ethnographic fieldwork. Interview guides and focus group discussions were the primary tools of data collection. The findings show that the relationships between formal institutions and traditional riverine fishing communities lack mutual trust. Conflicts between fishing communities and state agencies emerge when the formal institutions threaten or contradict those elements of local culture that sustain livelihood needs. Conflicts and discontent with a particular formal institution can also lead to the modification or violation of coexisting institutional arrangements.  相似文献   
213.
As inland wetlands face increasing pressure for development, both the federal government and individual states have begun reevaluating their respective wetland regulatory schemes. This article focuses first on the effectiveness of the past, present, and proposed federal regulations, most notably the Section 404, Dredge and Fill Permit Program, in dealing with shrinking wetland resources. The article then addresses the status of state involvement in this largely federal area, as well as state preparedness to assume primacy should federal priorities change. Finally, the subject of comprehensive legislation for wetland protection is investigated, and the article concludes with some procedural suggestions for developing a model law.  相似文献   
214.
浙江某热电厂运行的传统双碱法脱硫工艺出现了塔体结垢、脱硫渣得不到正常分离、脱硫效率低下、运行成本高等问题。本文主要分析与研究双碱法脱硫工艺的技术革新过程,并阐述经过技术革新后,新双碱法工艺的运行情况;真正实现了脱硫效率的大幅度提升;脱硫渣中石膏含量的提升;系统抗风险能力的提升。  相似文献   
215.
The environmental impact of industrial wastewater and higher cost of fresh water are the serious challenges faced by the process industries. It has led to the development of many new techniques to minimize fresh water consumption. Of the many approaches, which have been developed, the Water Source Diagram (WSD) is a flexible and dynamic alternative for the generation of different scenarios for the management of water networks with reduction in total consumption. In the present study WSD concept was coupled with water mains concept to mains simplify the piping network and reduce the cost. A new procedure was developed for integrating the effluent treatment processes to evolve Effluent Treatment Network. Example from literature having multi contaminants was considered. This simple procedure involving hand calculations will be a useful tool for process engineers to design water and effluent treatment networks. Also the WSD and ETN were combined to form an evolutionary WAMEN (Water Allocation and Mass Exchange Network) and the proposed WAMEN aims for minimum fresh water consumption.  相似文献   
216.
为解决施工过程安全信息的虚实交互难题,降低施工过程安全风险,提出施工过程安全数字孪生模型。建立施工过程安全语义本体,分析施工过程安全关键知识要素;定义施工过程安全数字孪生五维模型,明确模型的构成和功能,基于物联网和有限状态机构建施工过程安全监控方法,并以塔吊顶升活动安全监控为例进行应用。研究结果表明:该模型能够实现塔吊顶升施工过程安全的数字化表达、参数化监测和自动化控制。  相似文献   
217.
从系统论的角度,分析了工程项目风险产生机理,认为工程项目的内外部环境压力在工程项目当前状态施压后,工程项目的承压部分做出的恶化反应趋势是造成工程项目风险产生的根本原因。基于这一观点,提出了基于压力—状态—响应的项目风险辨识方法,该方法综合考查工程项目进行中所面临的内外部环境压力、项目当前状态和项目承压部分在压力下的反应趋势进行风险辨识;完善了项目风险确定的表述,认为项目风险事件的确定应由项目风险产生的环境因素和项目状态变动两个方面确定;设计了基于压力—状态—响应的项目风险辨识表。通过在某油气长输管道建设项目中的应用,验证了该方法的有效性和可行性。  相似文献   
218.
轻型机动车尾气排放测试研究   总被引:5,自引:0,他引:5  
通过在底盘测功机上进行轻型机动车的稳态负荷工况测试和瞬态负荷工况测试,进一步研究轻型机动车尾气排放污染物浓度、发动机输出功率、机动车行驶速度的相关性。并提出了通过计算排放变化率/加速度比例系数来确定稳态工况与瞬态工况的相关关系的方法,这对于I/M检测制度有很重要的技术意义。  相似文献   
219.
Intemational Vehicle Emissions (IVE) model funded by U.S. Environmental Protection Agency (USEPA) is designed to estimate emissions from motor vehicles in developing countries. In this study, the IVE model was evaluated by utilizing a dataset available from the remote sensing measurements on a large number of vehicles at five different sites in Hangzhou, China, in 2004 and 2005. Average fuel-based emission factors derived from the remote sensing measurements were compared with corresponding emission factors derived from IVE calculations for urban, hot stabilized condition. The results show a good agreement between the two methods for gasoline passenger cars' HC emission for all 1VE subsectors and technology classes. In the case of CO emissions, the modeled results were reasonably good, although systematically underestimate the emissions by almost 12%-50% for different technology classes. However, the model totally overestimated NOx emissions. The IVE NOx emission factors were 1.5-3.5 times of the remote sensing measured ones. The IVE model was also evaluated for light duty gasoline truck, heavy duty gasoline vehicles and motor cycles. A notable result was observed that the decrease in emissions from technology class State II to State I were overestimated by the IVE model compared to remote sensing measurements for all the three pollutants. Finally, in order to improve emission estimation, the adjusted base emission factors from local studies are strongly recommended to be used in the IVE model.  相似文献   
220.
Organophosphorus compounds (OPCs) and stable isotope ratios (δ13C and δ15N) were determined in 58 fishes belonging to 20 species collected from Manila Bay, the Philippines. OPCs were detected in most of the samples and found up to μg/g lw (lipid weight) level, suggesting their ubiquitous presence in the coastal marine environment of the Philippines. Higher levels (>1000 ng/g lw) of total OPCs were determined in yellowstriped goatfish, silver sillago, tripletail wrasse and bumpnose trevally indicates either their active uptake from ambient water or lower metabolic capacity of these species. Levels of triphenyl phosphate (TPhP) in demersal species showed a positive correlation with δ15N, indicating that TPhP was adsorbed onto the particle, settled down to the bottom sediment and accumulated through the benthic food web rather than the pelagic. Estimated dietary intake of OPCs in Manila Bay fishes were four to five orders of magnitude lower than the proposed reference dose (RfD).  相似文献   
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