Hydro-economic Modeling in River Basin Management: Implications and Applications for the European Water Framework Directive

Economic ideas and processes are becoming increasingly integrated with more traditional engineering and hydrologic models of water management problems. Combining economic management concepts and performance indicators with an engineering-level of understanding of a hydrologic system can provide results and insights more directly relevant for water management decisions and policies. When such models are developed and used with involvement of stakeholders, they can become a basis for shared understanding of water problems as a foundation for negotiated management and policy solutions. When implemented with optimization software, integrated hydro-economic models also can suggest promising innovative solutions for policy-makers to consider. Their applications to river basin management problems are reviewed. Economic and integrated economic-engineering-hydrologic modeling is then discussed in the context of the evolving European Water Framework Directive. Relevant items are cost recovery and water pricing, cost-effectiveness of water management measures, and public participation in decision processes.     

α-亚麻酸在部分食物中含量及性价比分析

必需脂肪酸中的α-亚麻酸(简写为ALA)对人体的健康起着不可或缺的作用,由于ALA在食物中含量相对较少并存在分布不均的情况,所以经常导致人们摄入不足。本文对《中国食物成分表》中的数据进行分析,筛选出ALA含量较高的食物,并通过其性价比研究,为人们日常饮食的选择提供参考。     

输电线路微型桩基础应用分析

针对输电线路杆塔在软土地基中的基础,结合国家电网公司“两型三新”试点线路建设的安排,拟在500kV庐桐一安庆变电站线路中河网、泥沼地段地基承栽力较低的塔位,采用微型桩基础代替一般的大直径钻孔灌注桩,文中通过微型桩基础和一般大直径灌注桩基础、钢筋砼板式基础的技术经济比较,分析出其社会经济效益并提出需近一步研究的问题和建议。     

Selection Criteria for Water Disinfection Techniques in Agricultural Practices

This paper comprises a selection tool for water disinfection methods for fresh produce pre- and postharvest practices. A variety of water disinfection technologies is available on the market and no single technology is the best choice for all applications. It can be difficult for end users to choose the technology that is best fit for a specific application. Therefore, the different technologies were characterized in order to identify criteria that influence the suitability of a technology for pre- or postharvest applications. Introduced criteria were divided into three principal components: (i) criteria related to the technology and which relate to the disinfection efficiency, (ii) attention points for the management and proper operation, and (iii) necessities in order to sustain the operation with respect to the environment. The selection criteria may help the end user of the water disinfection technology to obtain a systematic insight into all relevant aspects to be considered for preliminary decision making on which technologies should be put to feasibility testing for water disinfection in pre- and postharvest practices of the fresh produce chain.     

Multidimensional benefit–cost evaluation of asphaltic concrete overlays of rigid pavements

Using the data from a national study in the USA, this study demonstrated a comprehensive and multidimensional pavement treatment evaluation methodology and used the methodology to evaluate the short-term and life cycle cost-effectiveness (CE) of five rigid pavement rehabilitation treatments. Four measures of effectiveness were used in this study: the sudden decrease in surface roughness, treatment service life, increase in average pavement condition over the service life and the area bounded by the performance curve. This study established relationships that quantify the influence of pre-treatment condition on treatment effectiveness. Also, the models were developed to describe the treatment effectiveness as a function of traffic loading and climatic severity. It is seen that at high traffic loading, there is relatively little difference in treatment effectiveness across various climate severities. This study suggests that superior effectiveness of a treatment does not necessarily translate into superior CE. Also, the treatment location was found to influence the relative effectiveness of the treatments. Overall, the results suggest that treatment ‘crack-and-seat and 8-in. asphalt concrete overlay’ is the most cost-effective.     

药物合成微反应过程的开发

用微反应器替代常规间歇反应器处理药物合成反应取得很大的进展。本文讨论了微反应器的可行性论证和技术经济分析的方法,并对硝化反应的微反应器开发进行了初步论证。     

基于CSC方法的钢铁行业节能减排技术潜力分析

为了研究中国钢铁行业的节能减排潜力,以35项钢铁行业先进节能减排技术为研究对象,建立节能供应曲线(Conservation Supply Curve,简称CSC)模型,分析影响钢铁行业的节能减排收益、成本效益以及钢铁生产流程工序层面的节能减排潜力因素。结果表明,这35项技术全部应用可实现3.01 GJ/t的节能量以及398.22 kg/t的CO2减排量。将结果与第十三个五年计划推广技术作对比,在当前情况下,约有50%的推广技术并不符合成本效益;运用CSC模型进行了钢铁生产流程工序层面的节能减排潜力研究,得到各个工序的节能量和减排量,并据此分析了各项技术未来的发展趋势和应用前景。     

从欧洲水下防务展看鱼雷发展趋势

通过对最近几年欧洲水下防务展鱼雷技术的变化分析，总结了当代鱼雷的发展趋势。在研发思路上，西方鱼雷研制大国更加务实，走系列化发展道路，按照符合效费比的原则逐步改进鱼雷的性能，采用“制造-试验-制造”的方法，确保鱼雷武器在实战环境下的可靠、有效。在鱼雷设计上，目前主要改进领域集中在制导、推进、隐身、浅水等几个方面，并追求可靠性、保障性和低成本。其中，制导多采用标准总线和一体化设计，在开放式系统中采用COTS电子组件，具有较好的扩展性能，可快速进行软件升级和硬件改进，及时提高战术性能。实践证明，该研发思路符合需求，效果显著，能以最少的花费得到最出色的总体性能提升。     

双层球壳网架设计的优化分析——水泥厂石灰石预均化球型堆场优化设计

固化影响水泥厂仓储工程中双层球壳网架结构经济性的因素后，通过数据统计绘制双层球壳网架重量随着支座刚度变化的曲线图。分析影响该曲线变化的因素及原因，并依据此关系曲线选取合适的支座刚度，使依据此支座刚度对网架、网架支座、下部结构进行设计的网架工程项目在经济性上达到最优。     

A general theory of systems performance criteria

Based on general systems thinking of the past half century and the efficiency literature of the last 100 years, this research develops a theoretical model of systems performance criteria that provides a means to evaluate how well any living system, whether individual, organisational or societal, performs task-related activities in the pursuit of goals. The model is used as a foundation for organising the various concepts of performance that have evolved over the past century: efficiency, costs, productivity, effectiveness and cost-effectiveness. These performance concepts, derived from the theoretical model, are formalised into axioms that are used to deduce theorems and derivative laws in constructing a formal general theory of systems performance criteria.