电网可靠性评估的网络静态等值模型分析

为缓解大电网可靠性评估的计算复杂性,采取等值参数联合概率密度分布建模的方式开展了外网静态等值研究。在常规确定性静态Ward等值技术基础上,考虑外部区域发电机和线路随机故障,通过计算各种随机故障状态下的外网等值参数,即外网等值注入功率和外网等值串联支路阻抗,基于概率密度估计技术建立了等值参数的联合概率密度分布。外网静态概率等值模型克服了常规确定性静态Ward等值技术的不足,充分计入外网等值参数的随机性,减少了电网可靠性评估计算时间的同时提高了计算精度。对两区域RBTS系统和RTS79系统研究验证了其有效性和准确性。     

Research on reliability evaluation model for frequency collapse of power grid

In order to comprehensively consider the possibility and the severity of frequency instability risk, this paper proposes the risk evaluation model and algorithm for frequency collapse of power grid. The uncertainties in generating dispatch, network topology and component outage are considered. The calculation method for system frequency variation is depicted while considering the active power deficiency arising from random failure of generating units, and then various probabilistic risk indices for frequency collapse are defined. The presented method can provide important reference information for evaluating the frequency collapse risk of power grid. The non-sequential Monte Carlo simulation-based results of IEEE-RTS79 show the correctness of the method.     

Performance analysis of a concentrating solar hybrid photovoltaic thermal system

The photovoltaic components of a hybrid photovoltaic thermal (PV/T) system are combined with a solar thermal collector, which generates both thermal and electrical energy simultaneously with a higher integrated efficiency. A three dimensional steady model of the concentrating solar PV/T system which has a plate type metallic thermal collector with a serpentine rectangular channel is developed. The processes of photovoltaic and thermal transformation and heat transfer in the PV/T collector are calculated and simulated. The effects of the optical concentrating ratio, coolant mass flow rate, ambient air velocity and glass cover on both thermal and electrical performance of the collector are presented and discussed.     

Life cycle assessment in large air-conditioning system and evaluation framework model of energy utilization

Based on central air conditioning system of Xi'an-Xianyang international airport, energy efficient utilization with life cycle theory and analytic hierarchy process was conducted. Firstly, the application of life cycle and analytic hierarchy process to building energy was deeply studied. Secondly, life cycle inventory analysis was conducted combined with the practical cases data. And the data resource is related to the proposed model. Thirdly, On basis of analytic hierarchy framework model and analysis of energy consumption as well as potential environmental impact on air-conditioning project, the study on how to evaluate energy-consumption project with the use of life cycle impact assessment is done. Based on the life cycle assessment of practical cases data, a new hierarchical evaluation model of energy utilization is put forward. And in view of the model, several suggestions are given such as establishing energy utilization process monitoring and evaluation from the point of whole life cycle assessment. This provides a theoretical basis for policies about enormous quantity of building energy and energy saving of air conditioning system.     

RS UM based information system security assurance evaluation model

Based on the information system security assurance evaluation framework (GB/T20274),the information system security assurance model and evaluation index system are introduced, and the formalization evaluation method and flow are presented. An information security evaluation model is proposed by applying rough set (RS) and unascertained measure (UM) theory. At the criterion pre process period, rough set theory is used to obtain the key evaluation indexes and construct the reduced index set to simplify the original complex index system. At the evaluation period, unascertained measure model is adopted to analyze the evaluation data to implement a quantitative integration evaluation on the information system security assurance ability.     

A power distributed computing system model based on services-oriented architecture

Process communication based power distributed computing model satisfies the demand on real time monitoring and analysis for the economical operation of power grid based on power distributed computation methods, but there are some problems on complexity in common basic functions development and lack of system extendibility. An extendable services-oriented power distributed computation system model is designed and implemented. Software design patterns are applied to design low coupling and extendable system framework. Windows Communication Foundation (WCF) technology is used to implement the services-oriented distributed data communication functions. Windows Workflow Foundation (WWF) technology is used to design the business logic of power distributed computation visually. Data integration functions are implemented by combining the ADO.NET technology. The services-oriented system architecture enhances the integration ability and extendibility. The use of WCF and WWF technology reduces the complexity of the system development.     

A fast generation cycling system for oat and triticale breeding

A fast generation cycling system (FGCS) was developed in oat and triticale, allowing the production of pure line populations of the crops within 1‐year timeframe. Twelve oat and 12 triticale cultivars were tested using the FGCS, and most of them completed a generation cycle within 48–61 days under the system achieving up to seven generations a year. This system involves growing plants under stressed conditions to promote reproduction and in vitro culture of immature embryos bypassing full seed maturation. The developed system could be widely adopted in breeding and genetic studies of crops for producing desired segregating pure line populations, which could significantly shorten the breeding cycles.     

Comparative analysis on weight system of breeam industrial and Chinese evaluation system of industrial buildings

With the comprehensive development of green buildings, the evaluation system for domestic green industrial building is gradually established. By comparing the British BREEAM industrial and domestic standards green industrial building evaluation guide, after deep analyses from different views such as the weight system, evaluation process, the article obtains the similarities and the differences between the BREEAM and guide, and puts forward the viewpoint of weight system of evaluation system of domestic green industrial buildings.     

用灰色关联分析法综合评价印江县引入的杂柑新品种

[摘要]利用灰色系统理论的关联度分析原理和方法,综合评价了印江县引入的8个杂柑新品种。综合评价结果为：爱媛28号>天草>春见>南香>爱媛17号>爱媛14号>不知火>爱媛30号。爱媛28号品种建议直接推广,其它品种可根据当地的需要适当发展。     

石漠化防治区综合治理效益指标体系的构建及评价研究 ——以贵州关岭-贞丰花江示范区为例

以关岭-贞丰花江示范区为例,基于主成分分析模型,从生态效益、经济发展水平和社会发展水平3个方面进行评价指标的筛选以及指标权重的确定。最终确定影响生态效益的4个主要评价指标,影响经济发展水平的4个主要评价指标,影响社会发展水平的3个主要评价指标,构建出综合治理效益指标体系。根据选定的评价指标,采用模糊综合评判对花江示范区综合治理效益进行评价,将评价结果分为很差、差、一般、较好和很好5个等级。结果表明:示范区由治理前评价的"差"上升到治理后评价的"一般"。可以说明,治理措施在短期生态效益和经济发展水平方面有着良好的发展趋势,总体而言,治理措施具有良好的协调性和整体性。     

绿色制造剃齿切削油液选择模型及应用

切削液的合理选择是提高切削加工绿色化程度的重要途径之一。根据绿色制造原理,在首先满足加工质量的前提下,建立了一种综合考虑时间、质量、成本、资源消耗和环境影响5个因素的切削液评价体系。采用油基切削液和不同类型的水基切削液进行剃齿加工对比试验,从工件质量、刀具寿命、成本和资源环境影响几个方面进行对比分析。结合试验结果,利用模糊综合评价方法对加工结果进行了评价,并据此提出了用于剃齿加工的切削液综合选择模型,通过剃齿加工实例验证了该模型的可行性。试验证明：采用水基切削液进行剃齿加工仍能满足质量要求,与传统油基切削液相比,水基能有效降低生产成本,同时减少对环境的污染。     

Comprehensive dynamic fuzzy evaluation for construction safety of manual digging pile in limestone area

Based on the analysis of construction characteristics of manual digging pile in karst region, a scientific, timely and dynamic safety assessment system is the established and fuzzy AHP(analytic hierarchy process)is used to conduct a comprehensive safety assessment. The results are accordant with the actual situation and the construction practice has proved that fuzzy AHP is feasible to evaluate manual digging pile construction safety and good results can be achieved.     

A fault data recording system design for hybrid electric vehicles

A data recording system for fault diagnosis of hybrid electric vehicles was studied by taking the integrated starter and generator (ISG) hybrid electric vehicle as the investigation object. The fault diagnosis communication net was established using a CAN bus and a K line. As designed, the system hardware structure included a CPU processing module, a communication module, and a USB recording module. With the system requirements and characteristics in mind, special circuit design and analysis of USB mass storage module were carried out based on the hardware scheme and software design. In the running test, the fault data recording system worked stably, and the data was recorded integrally and correctly. At the same time, the online display data accurately reflected the vehicle's running status.     

Reliability evaluation algorithm for complex electrical distribution networks using the storage structure of adjacency multilist

A section algorithm of reliability evaluation for complex medium voltage Electrical Distribution Networks (EDNs) using adjacency multilist (AM) is proposed. The constructing method for AM is introduced. The AM can be used to store the structure data of EDNs and to solve the problem of space & time complexity. A new power flow algorithm of backward / forward sweep is proposed and a fast algorithm of forming sections in distribution network is put forward. The proposed algorithm makes a perfect combination of the power flow algorithm and the section algorithm of reliability evaluation, which makes efforts to decrease the work of programming and saves the computing time. Applying the proposed algorithm in RBTS-BUS6 system and actual EDNs, the reliability assessment results show that the algorithm has an advantage of saving time and possesses efficiency in engineering practicality.     

住宅建筑能耗基准确定及用能评价新方法

针对当前建筑能耗基准确定及用能评价方法仍不完善的现状,提出了一种适用于住宅建筑的新方法。通过灰色关联分析确定了不同影响因素(即特征参数)与建筑能耗的关联度,将关联度作为该因素的权值并结合聚类分析对建筑进行合理分类。在此基础上采用累积频率分布法确定了每类建筑的能耗基准值,并对建筑住户进行用能评价。为验证该方法的可行性,将其应用于日本建筑学会所建立的住宅建筑能耗数据库,为聚类后的每类建筑确定了相应的能耗基准并对住户进行了用能评价。结果表明该方法能够综合考虑不同特征参数的影响大小,科学合理地对建筑细化分类,根据分类后的基准评价能够更好地评估住户的节能潜力并提供可行的节能建议。     

Application of the CSM-CERES-Maize model for planting date evaluation and yield forecasting for maize grown off-season in a subtropical environment

In recent years, maize has become one of the main alternative crops for the Autumn–Winter growing season (off-season) in several regions of Brazil. Water deficits, sub-optimum temperatures and low solar radiation levels are some of the more common problems that are experienced during this growing season. However, the impact of variable weather conditions on crop production can be analyzed with crop simulation models. The objectives of this study were to evaluate the Cropping System Model (CSM)-CERES-Maize for its ability to simulate growth, development, grain yield for four different maturity maize hybrids grown off-season in a subtropical region of Brazil, to study the impact of different planting dates on maize performance under rainfed and irrigated conditions, and for yield forecasting for the most common off-season production system. The CSM-CERES-Maize model was evaluated with experimental data collected during three field experiments conducted in Piracicaba, SP, Brazil. The experiments were completely randomized with three replications for the 2001 experiment and four replications for the 2002 experiments. For the yield forecasting application, daily weather data for 2002 were used until the forecast date, complemented with 25 years of historical daily weather data for the remainder of the growing season. Six planting dates were simulated, starting on February 1 and repeated every 15 days until April 15. The evaluation of the CSM-CERES-Maize showed that the model was able to simulate phenology and grain yield for the four hybrids accurately, with normalized RMSE (expressed in percentage) less than 15%. The planting date analysis showed that a delayed planting date from February 1 to April 15 caused a decrease in average yield of 55% for the rainfed and 21% for the irrigated conditions for all hybrids. The yield forecasting analysis demonstrated that an accurate yield forecast could be provided at approximately 45 days prior to the harvest date for all four maize hybrids. These results are promising for farmers and decision makers, as they could have access to accurate yield forecasts prior to final harvest. However, to be able to make practical decisions for stock management of maize grains, it is necessary to develop this methodology for different locations. Future model evaluations might also be needed due to the release of new cultivars by breeders.     

青海省农作物品种管理数据库系统的建立及应用技术研究

青海省首次建成并使用的“青海省农作物品种管理数据库系统”是促进全省品种管理、合理推广应用优良品种，为社会提供品种咨询服务业务的信息系统工程，对发展农业生产，提高良种覆盖率具有很高的实用价值和理论意义。     

The equivalent enthalpy drop theory calculation of the ejector heaters applied for low-pressure feed water heater system of thermal power unit

There is much exergy loss in low-pressure feed water heater system of the thermal unit. The thermo-economic characters by the equivalent enthalpy drop method while the low-pressure heater was replaced with the ejector heater. At the same time, the thermo-economic characters formulas for the different factors were also gotten. Based on these results, the thermo-economic changing features were analyzed for the low pressure heaters replaced with the ejector heaters of the N600-165/535/535 units, and the results were compared with the normal heat balance method. The results show that the ejector heaters can reduce the exergy loss efficiently, and the thermo-economic effects is the best for replacing the all low-pressure heaters with the ejector heaters, and its efficiency can be increased by 0.263%. The given equations of this paper can be used for analyzing the thermal economic effects.     

Evaluation and use of a spatio-temporal model of cropping system effects on gene escape from transgenic oilseed rape varieties: Example of the GeneSys model applied to three co-existing herbicide tolerance transgenes

Gene flow between coexisting oilseed rape varieties and rape volunteers cannot be solely studied on field experiments. Previously, a model (GeneSys: [Colbach, N., Clermont-Dauphin, C., Meynard, J.M., 2001. GeneSys: A model of the inluence of croping system on gene escape from herbicide-tolerant rapeseed crops to rape volunteers. I. Temporal evolution of a population of rapeseed volunteers in a field. Agric. Ecosyst. Environ. 83, 235–253; Colbach, N., Clermont-Dauphin, C., Meynard, J.M., 2001. GeneSys: A model of the inluence of croping system on gene escape from herbicide-tolerant rapeseed crops to rape volunteers. II. Genetic exchanges among volunteer and cropped populations in a small region. Agric. Ecosyst. Environ. 83, 255–270]) was therefore developed to quantify the effects of cropping systems on gene flow from rapeseed varieties to rape volunteers in time and in space. In the present work, the model was improved to simulate simultaneously the spread of three different genes. Four different regions were then surveyed from 1995 to 2001: one region comprised only farmers’ fields with frequent rape crops in the rotations; the three remaining regions comprised the French experimental GMO platforms with 2–3 GM and one non-GM rape variety as well as neighbour farmers’ fields. For all these fields, cropping history was recorded during the study and for at least three previous years. In the first region, rapeseed volunteers were assessed in crops as well as on road and field margins in 1 year. In the three remaining regions, volunteer densities and genotypes were assessed each year after harvest and rape harvest genotypes determined during 2 years. The comparison of simulated and observed data showed that the model usually satisfactorily predicts volunteer densities and genotype proportions as well as harvest genotype proportions. Several problem areas were identified: volunteers in road and field margins were usually badly predicted; the model frequently underestimated volunteer densities in spring crops; gene flow via pollen dispersal was underestimated when the distance from the pollen source increased. The model was then used to simulate the spread of herbicide-tolerant rape volunteers in a region grown with one or several GM herbicide-tolerant varieties and more particularly the stacking of several resistance genes in individuals. The simulations also showed the contamination of the harvest of non-GM rape varieties by GM seeds resulting from gene flow.