大坝洪水漫顶风险评估

洪水漫顶是导致大坝溃坝的主要原因之一,大坝洪水漫顶风险评估是大坝风险评估的重要组成部分。为此,简要介绍了大坝洪水漫顶的风险模型,并通过实例详细地讨论了模型中各有关参数的不确定性处理方法,探讨了入库洪水的不确定性对洪水漫顶风险率的影响以及按规范设计的大坝的防洪能力问题。     

重油催化裂化装置的环保对策

对重油催化裂化过程中的环境影响因素、硫分布状况及硫平衡等进行了分析，指出了重油催化裂化过程中的环境污染问题；从对装置污染源的分析出发，提出了相关的治理措施。     

精品光网络建设策略--智能光网络的引入

简要介绍了ASON技术的特点、ASON的引入为新一代光网络带来的好处及衡量网络质量的一些参数和注意事项。     

The determination of the shelf-life of pasteurized and non-pasteurized sardine (Sardina pilchardus) marinades stored at 4 °C

In this study the shelf‐life of sardine marinades was investigated. After the marination process, sardine fillets were packed into glass jars with 2% citric acid, 4% sodium chloride and spices. The effect of pasteurization at 70 °C for 20 min on the shelf‐life of the sardine marinades was determined. At the end of 6 months storage the differences between thiobarbituric acid, free formaldehyde (FA(ex)), free and bound formaldehyde (FA(dest)) and peroxide value of pasteurized and non‐pasteurizated marinades were not significantly (P > 0.05) different, while the difference between total volatile basic nitrogen, trimethylamine, pH, total plate count and lactic acid bacteria count of pasteurized and non‐pasteurized marinades were. The shelf‐life of both pasteurized and non‐pasteurized sardine marinades was found to be 5 months at 4 °C.     

充分关注水质科学保障饮水安全

从我国饮水安全的现状入手，分析城乡饮水安全存在的问题，强调保障饮水安全是构建和谐社会的必然要求和水利工作的切实要务。从加强监测、科学规划，加强关键技术研究及推广应用，保护水源地、修复水环境，建立合理的体制与机制四个方面提出了做好保障饮水安全工作的建议。     

WASP6水质模型在渭河流域水环境容量解析中的应用

将WASP6水质模型应用于渭河流域陕西片,分析流域水环境的污染现状,并采用模型试错法模拟计算渭河陕西段水环境容量,并对比分析节水增流前后水质变化,根据分析结果提出节水增流减污的水污染控制方案,为渭河的污染治理提供依据。     

Effects of low radiation on the power quality of a distributed PV-grid connected system

We have previously investigated effects of radiation levels on power quality of a number PV-grid interactive systems in Thailand, in terms of harmonics and voltage variation at the point of common coupling (PCC). In this paper, we focus on the nature of components of complex power (actual, reactive and apparent power) of inverter output of a PV-grid interactive system due to low radiation, below 400 W/m². The system being investigated has an array of 4.2 kWp and representative of roof top units. It is observed that a PV array supplies increasing real power, in magnitude and as percentage of complex power, at high values of radiation. At low radiation level when the array does not provide enough output power, reactive power is drawn from distribution transformer and fed into an inverter and loads. Based on results from the test site and long term radiation data of Bangkok, we then estimate energy available from low radiation from a hypothetical PV-grid interactive unit in Bangkok of a similar size. It can be seen that for a tropical climate like Thailand a significant amount of energy, 20–30% of radiation energy, is in the form of reactive power. Methods must be devised to capture this low radiation energy and converted into real power form.     

Effect of sampling density on the measurement of stream condition indicators in two lowland Australian streams

There is widespread application of indicators to the assessment of environmental condition of streams. These indicators are intended for use by managers in making various comparative and absolute assessments and often have a role in resource allocation and performance assessment. Therefore, the problem of formally defining confidence in the results is important but difficult because the sampling strategies used are commonly based on a compromise between the requirements of statistical rigour and the pragmatic issues of access and resources. It is rare to see this compromise explicitly considered and consequently there is seldom quantification of the uncertainty that could affect the confidence a manager has in an indicator. In this paper, we present a method for quantitatively assessing the tradeoffs between sampling density and uncertainty in meeting various monitoring objectives. Assessments using judgement‐based representative reaches are shown to be unreliable; instead a sampling approach is recommended based on the random selection of measuring sites. A detailed dataset was collected along two streams in Victoria, Australia, and the effect of sampling density was assessed by subsampling from this dataset with precision related to the number of sites assessed per reach length and the intensity of the sampling at each site. The sampling scheme to achieve a given precision is shown to depend on the monitoring objective. In particular, three objectives were considered: (1) making a baseline assessment of current condition; (2) change detection; and (3) detection of a critical threshold in condition. Change detection is shown to be more demanding than assessing baseline condition with additional sampling effort required to achieve the same precision. Sampling to detect a critical threshold depends on nominating acceptable values of Type I and II error and the size of the effect to be detected. Copyright © 2006 John Wiley & Sons, Ltd.     

常规施工中不容忽视的几个环节

就毛石砌体的拉接处理、现浇混凝土柱、墙拉结筋的留设、砖混结构中构造柱的质量预控等几个环节进行了分析，提出只有在施工中采取必要的措施，才能保证施工质量。     

侯运高速公路施工质量控制资料的编制与管理

介绍了侯运高速公路施工质量控制资料的编制和管理的现状 ,阐述了工程施工质量控制资料的特点和依据 ,指出只有提高资料编制人员的自身素质 ,才能搞好资料管理工作