半干法脱硫配套电除尘器选型分析

某新建135MW机组锅炉为循环化床锅炉,其烟气处理系统采用半干法脱硫工艺加电除尘器。由于半干法脱硫后电除尘器入口的粉尘浓度非常高,且烟尘理化性质发生较大变化,除尘难度大,常规电除尘器的选型很难适应。分析了半干法脱硫后电除尘器选型的影响因素及各系数取值。     

Environmental Impact Evaluation Model for Industrial Processes

This paper proposes a model to evaluate the environmental impact of manufacturing processes. This model uses the potency factor approach to classify environmental impacts into five ecological health impact groups and uses their toxicological, cancer, and physical effects as the bases to rate the seven groups of human health impacts. The environmental impacts in each impact group are reported, and their hazard scores on ecological and human health are determined. The model also generates a single score for the overall environmental impacts of a process. This single score system helps to identify, among all the viable processes, which is the most environmentally friendly process. This model can serve as a tool to highlight the potential environmental hazards of process operations and to provide information about environmental performance for decision making. The model has been developed into a computer software program, Environmental Impact Evaluation System, and is demonstrated by using the processes employed for the manufacture of paper bags.     

Setting up the criteria and credit-awarding scheme for building interior material selection to achieve better indoor air quality

Methods, standards, and regulations that are aimed to reduce indoor air pollution from building materials are critically reviewed. These are classified as content control and emission control. Methods and standards can be found in both of these two classes. In the regulation domain, only content control is enforced in some countries and some regions, and asbestos is the only building material that is banned for building use. The controlled pollutants include heavy metals, radon, formaldehyde, and volatile organic compounds (VOCs). Emission rate control based upon environment chamber testing is very much in the nature of voluntary product labeling and ranking, and this mainly targets formaldehyde and VOC emissions. It is suggested that radon emission from building materials should be subject to similar emission rate control. A comprehensive set criteria and credit-awarding scheme that encourages the use of low-emission building material is synthesized, and how this scheme can be practiced in building design is proposed and discussed.     

A Single-Use Site Selection Technique, Using GIS, for Aquaculture Planning: Choosing Locations for Mangrove Oyster Raft Culture in Margarita Island, Venezuela

Oyster culture has a potential to generate income for coastal communities and to lessen pressure on natural overexploited populations. A project to transfer mangrove oyster Crassostrea rhizophorae raft culture technology to selected coastal communities in Margarita Island, Venezuela is being developed, and an optimum location selection technique was devised. To pick the variables or factors that determine site suitability, a bibliographic database was made, aspects of interest chosen, and the most comprehensive ones singled out, eliminating redundant ones. Twenty variables were grouped in criteria based on the way they influence the project. Variables were classified as intrinsic environmental, environmental extrinsic, logistic, and socioeconomic criteria. Thirty-five experts were asked to evaluate the factors and to score each according to their suitability weight. Logistic criterion received the highest values, followed by environmental extrinsic issues. A Geographic Information System using a base map compiled from 1:25,000 scale maps was developed. A thematic map for each factor was completed, dividing graphically the 3896-km² study area into polygons of equal weight for each factor. The Multi-Criteria Evaluation (MCE) was used to combine the variables. Resultant vectors in thematic maps were added to obtain smaller polygons with the same value sum. Finally, MCE was used to generate a final output: the optimum sites for oyster aquaculture resulting from the added values of over 3000 polygons in the maps, for the 20 criteria. Higher scores were reached in 13 areas covering 4.1 km², those places having the optimum conditions for oyster raft aquaculture in the region. Additional locations meeting 75% to 70% of the demanded criteria for a final suitable selection cover 137 sites encompassing 37.5 km².     

成都麻羊保种选育实施方案的探讨

本文介绍了成都麻羊品种特征、体型结构、生产性能及其产区概况，讨论了保种选育的方向、指标和种群建设规模；提出了规划保种区、建立良种繁育体系、组建保种核心群、严格选种选配、科学饲养、合理培育、健全卫生防疫制度等配套技术措施，以及强化管理、加强协作、扶持发展专业户、搞好技术培训、合理利用等组织措施。     

EXPERIENCE WITH THE 303-208-201 STUDY RELATIONSHIPS1

ABSTRACT: The current 201 study by the Bergen County Sewer Authority illustrates possibilities for improving the currently defined relationships between 201, 208 and 303 studies. The Bergen County Sewer Authority serves 115 square miles in northeast New Jersey, providing sewerage service to 507,000 people in 43 municipalities. Its STP discharges to the Hackensack River, a tidal estuary recently classified as Water Quality Limited, and which receives significant non-plant loading. The subject 201 study is concurrent with 208 and 303 planning by NJDEP. Preliminary evaluations show that detailed 201 work can affect the conclusions of 303 and 208 studies, and that a wider (environmental - social as well as economic) interpretation of cost-effectiveness can demand re-examination of prior assumptions and decisions, a task not typically part of 208–303 work. Increased flexibility is needed in applying 303 and 208 recommendations to defining 201 studies and NPDES permit criteria, particularly in analysis of water use objectives, water quality parameters and future flows, loadings and facility costs. Further, perception of alternatives can be clarified by broadening analysis of costs and control and plant strategies. Inclusion of 201 planning at all stages of regional planning can synergistically improve the total planning process.     

A comprehensive framework for assessing and selecting appropriate scaffolding based on analytic hierarchy process

Problem: Bamboo scaffolding has been widely used in South China, Hong Kong, and Southeast Asia for many years. Bamboo scaffolding is more economical, but its safety record is relatively poor. Conversely, metal scaffolding is more expensive, but its use in these regions has increased in recent years because it is relatively safe. The assessment and selection of the most appropriate type of scaffolding for a particular construction project is always a concern for project managers. Method: This paper suggests a comprehensive assessment framework that enables project managers to take a number of major quantitative and qualitative factors into consideration when making scaffolding decisions. This framework is based on the Analytic Hierarchy Process methodology and a survey among project managers in Hong Kong. Results: The research reveals that the overall performance of metal scaffolding is believed to be better than bamboo scaffolding. A sensitivity analysis has also been conducted to investigate the impact of various factors on the final decisions. Impact on Industry: The proposed assessment framework can be used as a supporting tool for project managers in the selection of scaffolding for their projects.     

华北地区防火树种筛选

针对华北地区34种树种的燃烧特性、生物学特性和生态学特性进行了实验与调查分析，利用层次分析的方法对测试树种的防火能力进行了排序。研究结果表明，刺槐、核桃、加杨、青杨的防火能力强，旱柳、火炬树等树种的防火能力综合得分值高，相对防火能力强。     

A Technicoeconomic Approach for the Selection of a Site Remediation Strategy—Part A: Theory

A technicoeconomic model is developed to select an optimal strategy for the remediation of a contaminated site and to determine the value of this remediation strategy. The model is an extension of actual cost–benefit analysis, with consideration of “irreversible” remediation technology choices, technology effectiveness, and uncertainty on the site's level of contamination. The model considers the possibility of reducing uncertainty by both acquiring more and better information on the level of contamination and by offering the decision-maker the opportunity to reevaluate his decision and switch to a more appropriate technology. It is believed that this model will help decision-makers in the selection of a remediation strategy by presenting all potentially feasible strategies, and how uncertainty on the site's level of contamination affects these strategies.     

PERIODIC AUTOREGRESSIVE-MOVING AVERAGE (PARMA) MODELING WITH APPLICATIONS TO WATER RESOURCES1

Results involving correlation properties and parameter estimation for autoregressive-moving average models with periodic parameters are presented. A multivariate representation of the PARMA model is used to derive parameter space restrictions and difference equations for the periodic autocorrelations. Close approximation to the likelihood function for Gaussian PARMA processes results in efficient maximum-likelihood estimation procedures. Terms in the Fourier expansion of the parameters are sequentially included, and a selection criterion is given for determining the optimal number of harmonics to be included. Application of the techniques is demonstrated through analysis of a monthly streamflow time series.