基于组合赋权法的农村地区分布式能源系统综合评价

为了对农村地区分布式能源系统的综合效益作出评价,针对某分布式能源系统项目从节能性、经济性与环境性三方面建立了评价指标体系,提出了层次分析法(AHP)与熵值法相结合的主客观组合赋权方法,并构建了基于组合赋权法的逼近理想解排序法(TOPSIS)多属性综合评价模型,对各个运行方案的综合效益进行了优劣排序。研究结果表明:评价指标中经济性指标权重占比为0.415 2,农村地区在确定分布式能源系统运行方案时需首先考虑系统的经济性;分布式能源系统以沼气作为燃料系统的综合效益要好于天然气,对于生物质能相对丰富的农村地区宜采用沼气作为供能系统的燃料。

燃气冷热电三联供系统节能性与经济性分析

燃气冷热电三联供(CCHP)系统作为分布式能源的一种,基于能量梯级利用思想,能够向用户提供电、热、冷多种能量,具有节能、经济、环保、安全可靠等多方面的优势。选取天然气发电、燃气锅炉供热、燃气发电制冷的分供系统为比较基准,通过建立数学模型,对CCHP系统与分供系统的节能性与经济性进行了分析对比。结果表明:要提高CCHP系统的节能性,除了选用较高发电效率的动力装置之外,根据余热形式及特点,合理选取高效的余热回收装置,充分利用发电余热,提高系统供热效率是关键;此外,根据负荷特点等因素合理确定系统运行模式也有助于提高系统节能性。分析了气电价比等因素对CCHP系统经济性影响,并对该系统的进一步发展提出了建议。

考虑二氧化碳排放的冷热电联供系统的容量配置

节能减排已被纳入国家经济社会发展规划之中。冷热电联供CCHP(combined cooling,heating and power)系统因其高效、碳排放量少而被广泛应用。针对多种发电单元的CCHP系统容量配置问题,建立了综合考虑二氧化碳排放量、系统总成本的规划模型,并采用CPLEX优化软件求解。采用Energy Plus软件模拟计算某宾馆的全年逐时冷、热、电负荷,仿真分析4种不同CCHP系统的容量配置方案,以及不同权重系数对系统容量配置的影响。最后对系统容量配置关于天然气价格和电价的灵敏度进行分析。本研究内容为CCHP系统的规划提供了一定的理论支持。

楼宇冷热电联供系统节能性研究

以济南地区一幢六层住宅楼冷、热、电负荷计算为基础,对基于小型燃气内燃机和微型燃气轮机的楼宇冷热电联供系统进行节能性研究。对系统余热利用情况和一次能耗率PER值进行计算,并将计算结果与分供式能量系统进行了比较,得出楼宇冷热电联供系统的节能性。研究结果表明,系统余热利用情况和主要设备运行效率是影响楼宇冷热电联供系统节能性的主要因素,系统方案选择应兼顾考虑应用场合冷、热、电负荷需求比例情况。

浅议配电系统中供电可靠性

配电系统是直接连接用户的系统,其供电可靠性对用户有着重要的影响。本文对配电系统的影响供电可靠性的因素、可靠性分析内容以及提高系统供电可靠性的措施等方面进行了研究。

Optimal Dispatching of Large-scale Water Supply System

This paper deals with the use of optimal control techniques in large-scale water distribution networks. According to the network characteristics and actual state of the water supply system in China, the implicit model, which may be solved by utilizing the hierarchical optimization method, is established. In special, based on the analyses of the water supply system containing variable-speed pumps, a software tool has been developed successfully. The application of this model to the city of Shenyang (China) is compared to experiential strategy. The results of this study show that the developed model is a very promising optimization method to control the large-scale water supply systems.

A dynamic optimization model of an integrated coal supply chain system and its application

Various nodes,logistics,capital flows,and information flows are required to make systematic decisions concerning the operation of an integrated coal supply system. We describe a quantitative analysis of such a system. A dynamic optimization model of the supply chain is developed. It has achieved optimal system profit under conditions guaranteeing a certain level of customer satisfaction. Applying this model to coal production of the Xuzhou coal mines allows recommendations for a more systematic use of washing and processing,transportation and sale resources for commercial coal production to be made. The results show that this model,which is scientific and effective,has an important value for making reasonable decisions related to complex coal enterprises.

Burning Cave-Pipe Coil-Kang Coupled Heating System Research

Nowadays,people still rely on traditional heating methods in rural areas of northern China,such as Kang(bed-stoves) and burning caves in cold winter.Field measurements of indoor environment were carried out in several rural houses with burning-cave-coil-Kang coupling heating system in northern China.The results show that this system is able to realize the graded use of internal energy of burning cave.The temperature of supply pipe water ranged from 30 ℃ to 50 ℃ which met the demands in 74.7% of time.The surface temperature of Kang maintained at above 25 ℃.Compared with traditional burning cave,using burning-cave-coil-Kang coupled with heating system has a higher thermal efficiency of 48.9%,which is 8.32% higher than the traditional one.

Application of Air Separation Unit in SINOPEC's Coal Chemical Business

With the rapid growth of coal chemical industry in China, the selection and application of Air Separation Unit(ASU) became very important. As the core unit in coal chemical industry, ASU will greatly impact the engineering construction and operation/production of coal chemical business. In this paper, major suppliers of ASU at home and abroad were reviewed, and the major supplying status of ASU in China was introduced. The ASUs in operation of SINOPEC were listed and discussed. On this basis, some suggestions of ASU selection strategies were provided on localization, standardization and operation methods.

Research on the Development of SCM System for the Textile and Garment Industry Based on UML

This thesis systematically analyzes the essential structure of supply chain management system for the textile and garment industry based on UML. According to these analyses, an advanced, reasonable and practical preliminary system has been constructed to simulate the operation process and evaluate design standard of the supply chain.

Exergetic Comparative Analysis of Ammonia and Carbon Dioxide Two-Stage Cycles for Simultaneous Cooling and Heating

The paper deals with the comparative analysis of the performance of cooling and heating systems operating with NH3 （ammonia） or CO2 （carbon dioxide）, both natural refrigerants. The study is based on the exergetic analysis that points out the location and the magnitude of a system malfunction. Both systems, with NH3 or CO2 operate in two stages. The exergetic analysis gives the direction of the structural optimization. The exergetic analysis has shown that the best structural schematic is not the same for the two agents. The exergetic analysis points out that the largest exergy destruction in the CO2 cycle is due to the throttling process and offers solutions to diminish it.

Partial Least Squares Regression Model to Predict Water Quality in Urban Water Distribution Systems

The water distribution system of one residential district in Tianjin is taken as an example to analyze the changes of water quality.Partial least squares(PLS) regression model,in which the turbidity and Fe are regarded as control objectives,is used to establish the statistical model.The experimental results indicate that the PLS regression model has good predicted results of water quality compared with the monitored data.The percentages of absolute relative error(below 15%,20%,30%) are 44.4%,66.7%,100%(turbidity) and 33.3%,44.4%,77.8%(Fe) on the 4th sampling point;77.8%,88.9%,88.9%(turbidity) and 44.4%,55.6%,66.7%(Fe) on the 5th sampling point.

Research on The Elderly Spiritual Demand in China

Spiritual demand as one of the basic requirements of human, has more important significance for the elderly group. Descriptive statistic analysis shows that in the CLHLS, the elderly spiritual demand and supply is in a state of disequilibrium in our country, supply is far less than demand. The main factors of restricting the old people＇s spiritual need are not being met, including economic factors, intergenerational relations factors, emotional factors and the particularity of spiritual demand, etc. So we need to change our ideas, with the demand of the old structure and strength, by constructing a complete supply system of family, society and government to strengthen for the supply of the spiritual needs of old people, so that the elderly would be happy during his or her later lives.

Research on Intrusion Detection Method of Web Service Composition

The paper takes Web service composition document as the research object, through the analysis of the documents, the port and address on the Web server, to create a Web intrusion detection model. The core of the model will monitor the Web server host resources, and finally discusses in detail the design and implementation of resource monitoring system. Intrusion detection model proposed can effectively regulate the behavior of users in this paper, allowing users follow a pre-standard service to call service providers, largely to protect the security of Web services.

Use of Multi-criteria Decision Analysis Methods for Water Supply Problems： A Framework for Improved Rainwater Harvesting

Several conflicting objectives are considered in decision-making. MCDA （multi-criteria decision analysis） methods are developed to facilitate better decision making by decision-makers. Water supply problems are complex problems with multiple decision making and criteria. Hence, the use of multi-criteria decision analysis is very appropriate for solving these problems. Multi-criteria decision analysis can be divided into three main groups： value measurement models, goals, aspiration and reference level models and outranking models. The methods listed have been applied to water supply problems, especially in the evaluation of alternative water supply strategies. Each method has its advantages and limitations. A good alternative for concluding a better-suited method for water supply problems is to apply more than one method, either in combination to make use of the strengths of both methods, or in parallel to obtain a broader decision basis for the decision maker. Previous studies of MCDA in water supply planning have usually considered water supply networks with only one water service delivery. Advanced water supply sources with multiple water service delivery systems have been neglected. This is an on-going study in which analytical hierarchical multi-criteria decision analysis methods are proposed for solving water supply problems and a framework for improved rainwater harvesting systems will be developed.

Inverse Problem and Variation Method to Optimize Cascade Heat Exchange Network in Central Heating System

Urban heating in northern China accounts for 40% of total building energy usage. In central heating systems, heat is often transferred from heat source to users by the heat network where several heat exchangers are installed at heat source, substations and terminals respectively. For given overall heating capacity and heat source tempera- tore, increasing the terminal fluid temperature is an effective way to improve the thermal performance of such cascade heat exchange network for energy saving. In this paper, the mathematical optimization model of the cas- cade heat exchange network with three-stage heat exchangers in series is established. Aim at maximizing the cold fluid temperature for given hot fluid temperature and overall heating capacity, the optimal heat exchange area dis- tribution and the medium fluids＇ flow rates arc determined through inverse problem and variation method. The preliminary results show that the heat exchange areas should be distributed equally for each heat exchanger. It al- so indicates that in order to improve the thermal performance of the whole system, more heat exchange areas should be allocated to the heat exchanger whore flow rate difference between two fluids is relatively small. This work is important for guiding the optimization design of practical cascade heating systems.

A GA Based Algorithm to Solve the Multi-stage Supply Chain Optimization Problem

The multi-stage supply chain optimization problem is an important subject for research. Syaxif et al. have studied the problem formulated by a 0-1 mixed integer linear programming model, and presented a st-GA （spanning tree-based genetic algorithm） by using Priifer number representation as the solution method of the model. On the basis of the work done by Syarif et al., a rst-GA （revised st-GA ） to solve the multi-stage supply chain optimization problem, is presented in this paper by means of introducing new sym- metric encoding ＆ decoding procedures of Priifer number, and adopting new chromosome＇s decoding strategy, etc. To facilitate building related decision-making support system, a C language implementation method of the rst-GA is also presented in this paper. Numerical experiments have validated that the rst-GA has better performance than the st-GA.