不同土地利用方式对流域非点源污染模拟的影响

以淮河上游息县水文站以上为研究区域,基于2000年以后土地利用数据分析不同土地利用对流域非点源污染的影响,根据流域附近5个气象站2002～2008年资料应用P-M法耦合植物生长模型计算流域潜在蒸散发作为模型的蒸发输入,并基于2002～2008年63个雨量站资料及尺度为1∶200 000土壤类型图、土壤化学属性和农业施肥资料,运用SWAT模型模拟分析流域非点源污染时空分布特征,统计分析了流域内不同土地利用方式下产污特征。结果表明,在降雨量与土壤质地相同情况下,非点源污染负荷旱地>水田>林地,可为淮河上游生态建设提供参考。     

南水北调东线治污的探索与实践

南水北调东线工程沿线的治污工作关系到工程成败。十年来,围绕建设输水干线"清水廊道"的目标,东线工程在创新规划实施思路、完善管理体制、健全法规标准、改革运行机制、建立全防全控治污体系等方面,做了大量尝试和实践,探索出了一条适合南水北调东线实际的治污道路,取得了明显的治理效果,为东线一期工程顺利通水奠定了坚实基础,为其他重点流域治污提供了有益借鉴。     

南水北调中线工程测量基准建设方案研究

南水北调中线工程测量基准建设方案是在充分调研工程区域现有测量体系基础上,针对南水北调中线工程的特点,建立的满足工程建设要求的测量基准建设方案,主要建立B级GPS骨干网、渠线C级GPS平面控制网、全线二等水准网和建筑物施工控制网等多层次、高精度、大范围的测量基准,全面地解决了区域内控制点之间空间上、时间上存在的不兼容性问题,对类似长距离工程测量基准的建立方法、控制等级、技术指标、数据处理等具有很好的借鉴作用。     

Renewable energy technologies for the Indian power sector: mitigation potential and operational strategies

The future economic development trajectory for India is likely to result in rapid and accelerated growth in energy demand, with attendant shortages and problems. Due to the predominance of fossil fuels in the generation mix, there are large negative environmental externalities caused by electricity generation. The power sector alone has a 40 percent contribution to the total carbon emissions. In this context, it is imperative to develop and promote alternative energy sources that can lead to sustainability of the energy–environment system. There are opportunities for renewable energy technologies under the new climate change regime as they meet the two basic conditions to be eligible for assistance under UNFCCC mechanisms: they contribute to global sustainability through GHG mitigation; and, they conform to national priorities by leading to the development of local capacities and infrastructure. This increases the importance of electricity generation from renewables. Considerable experience and capabilities exist in the country on renewable electricity technologies. But a number of techno–economic, market-related, and institutional barriers impede technology development and penetration. Although at present the contribution of renewable electricity is small, the capabilities promise the flexibility for responding to emerging economic, socio–environmental and sustainable development needs. This paper discusses the renewable and carbon market linkages and assesses mitigation potential of power sector renewable energy technologies under global environmental intervention scenarios for GHG emissions reduction. An overall energy system framework is used for assessing the future role of renewable energy in the power sector under baseline and different mitigation scenarios over a time frame of 35 years, between 2000 to 2035. The methodology uses an integrated bottom-up modelling framework. Looking into past performance trends and likely future developments, analysis results are compared with officially set targets for renewable energy. The paper also assesses the CDM investment potential for power sector renewables. It outlines specific policy interventions for overcoming the barriers and enhancing deployment of renewables for the future.     

The study of a maintenance float model with gamma failure distribution

This paper considers an operational system made up of a number of independent and identical units. A given number, N, must be in service and it is supported by a maintenance float. We estimate the float factors using a Taylor series approximation of the gamma distribution for failures and a log normal function for repairs. From the model developed for the gamma case, the exponential, erlang-2 and degenerate cases are obtained. It is shown that the maintenance float factors approach asymptotic values for large N, This paper extends the previous research on maintenance float modelling and shows that the maintenance float factors are independent of N for large values of N. This property is used to obtain a simpler formula for maintenance float factor for the gamma failure distribution. Unlike the formulae obtained for the cases of exponential and Weibull failure distributions, the gamma failure yields a more complex formula. The asymptotic model considerably reduces the computational efforts involved.     

Graphene formation by unzipping carbon nanotubes using a sequential plasma assisted processing

We report the realization of graphene nanosheets by means of unzipping carbon nanotubes grown on silicon substrates. The formation of carbon nanotubes is possible with a gas mixture of methane and hydrogen in a direct-current plasma enhanced chemical vapor deposition reactor at a temperature of 700 °C. To avoid the undesired agglomeration of nickel islands as the catalyst layer, a hydrogen-assisted pre-treatment has been used. Vertically aligned CNTs are placed horizontally on a silicon substrate and unzipped using a sequential passivation and etching process in a reactive ion etching unit. A mixture of hydrogen, oxygen and SF₆ gases are used to result in proper unzipping of horizontal CNTs. Scanning electron microscopy, transmission electron microscopy, atomic force microscopy and Raman spectroscopy have been exploited to investigate the physical properties of the grown nano-structures. In addition, the composition of the passivation layer has been examined using energy dispersive spectroscopy. Multilayered graphene sheets with a height of 3 nm have been obtained.     

计算机软件商业秘密的法律保护

本文描述了我国计算机软件企业对商业秘密的认识不清晰,导致纠纷频出,而现有的商业秘密保护的法律依据还不够完善,在这种情况下对计算机软件企业遇到商业秘密纠纷时,如何运用司法鉴定作为救济途径,更好的保护自己的知识产权提出相关建议。     

Winning customer loyalty in an automotive company through Six Sigma: a case study

Six Sigma is a disciplined approach to improving product, process and service quality. Since its inception at Motorola in the mid 1980s Six Sigma has evolved significantly and continues to expand to improve process performance, enhance business profitability and increase customer satisfaction. This paper presents an extensive literature review based on the experiences of both academics and practitioners on Six Sigma, followed by the application of the Define, Measure, Analyse, Improve, Control (DMAIC) problem‐solving methodology to identify the parameters causing casting defects and to control these parameters. The results of the study are based on the application of tools and techniques in the DMAIC methodology, i.e. Pareto Analysis, Measurement System Analysis, Regression Analysis and Design of Experiment. The results of the study show that the application of the Six Sigma methodology reduced casting defects and increased the process capability of the process from 0.49 to 1.28. The application of DMAIC has resulted in a significant financial impact (over U.S. $110 000 per annum) on the bottom‐line of the company. Copyright © 2006 John Wiley & Sons, Ltd.