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Abstract: Within a four year joint research project the technical feasibility of thermo-chemical heat storage for solar thermal applications and the achievable advantages compared to conventional storage technologies have been investigated. The project, directed to applied research, was divided into a high temperature (> 300°C) and a low temperature part (< 100°C). In the low temperature part the main focus was on the development of a compact seasonal heat store for single or multifamily houses. Concerning high temperature applications thermo-chemical energy stores show high potential for improving energy efficiency of power plants and for recovery of process heat. The investigations have been carried out by a close cooperation of the Institute of Thermodynamics and Thermal Engineering (ITW) of the University of Stuttgart, specialised for solar thermal heating in the building sector and the Institute of Technical Thermodynamics (ITT) of the German Aerospace Center (DLR) as a specialist on solar thermal power plants. The project started in 2008 and runs until end of June 2012. This paper will focus on the low temperature part of the project, discuss important experiences and recent experimental results of the project and will report the very latest developments. Moreover the paper will summarise the important improvements achieved for temperature thermo- chemical heat storage. Finally recommendations for future activities will be given. [Copyright &y& Elsevier]

Abstract: This paper presents practical performance study of one axis mechanical tracking of PV grid connected system, which is designed, studied, and analyzed comparing with a fixed PV system at HIAST with capacity of 100 watts with tilt angle 35 degrees. This paper presents and compares the capital costs of tracking and fixed systems and the energy injected into the grid. [Copyright &y& Elsevier]

Abstract: The requirements of device under the multi-mission of monitoring, protecting, controlling and communicating is discussed in this paper to bring forward a design of dual CPU structure with ARM & DSP for microprocessor protection. Via the comparative analysis of several common algorithms, the algorithm of FFT, which can make the controlling of calculation accuracy easier and has a filter feature inherently, is selected to analyze the sampling data of protector and calculates relative electrical parameters. Relevant program is written for distance protection in 110kV transmissions, then debugging on software and hardware is made. The results show that the design of DSP & ARM based-microprocessor protection presented in this paper is feasible; such a device has simple and reliable circuit structure and is expandable in both software and hardware. [Copyright &y& Elsevier]

Abstract: In this paper, taking the ENVISAT satellite SAR images in Bam city as an example, the authors construct Digital Elevation Model (DEM) with InSAR technology, and by comparing the InSAR DEM with SRTM-3 DEM they also research the relationship between InSAR DEM''s precision and terrain factors represented by slope and aspect. The results show that the elevation difference mean error between InSAR DEM and SRTM-3 DEM of the experiment area is 12.50 meters, and the precision is reduced with the increase of slope but basically has nothing to do with aspect. In this paper, taking the ENVISAT satellite SAR images in Bam city as an example, the authors construct Digital Elevation Model (DEM) with InSAR technology, and by comparing the InSAR DEM with SRTM-3 DEM they also research the relationship between InSAR DEM''s precision and terrain factors represented by slope and aspect. The results show that the elevation difference mean error between InSAR DEM and SRTM-3 DEM of the experiment area is 12.50 meters, and the precision is reduced with the increase of slope but basically has nothing to do with aspect. [Copyright &y& Elsevier]

Abstract: It is complicate to process the seismic data from the area below a fault, where there is the pull-up and sag phenomenon in seismic section. And geological processors are difficult to make sure whether the pull-up and sag really exist. So this phenomenon of pull-up and sag makes the fault shadow problem. This paper makes a forward simulation research deeply and presents many different geological models to execute forward numerical simulation. Many common processing flows and migration imaging methods are analyzed and used to overcome the fault shadow problem. At last, this paper concludes one fairly suitable method to resolve the fault shadow problem by comparing the different migration methods. [Copyright &y& Elsevier]

Abstract: From the securities investment funds style index theoretical basis, this paper analyses its securities investment funds invest in the market. By using comparative analysis of the domestic and foreign investment style index for research and studies, it showed that the domestic and foreign investment style index were obvious differences in the categorized style, selection and classification standards of model style. In conclusion, this paper has made some suggestion for our country''s securities investment market from the application of investment in style from the financial derivatives [Copyright &y& Elsevier]

Abstract: This paper constructs a framework for collaborative government portal system based on semantic Web service, with detailed description of the framework model and in-depth analysis of the key technologies involved in the framework. What''s more, it also builds ontology conceptual model and analyses on the implementation steps of the system. Finally, through case comparison analysis this paper confirms the theoretical basis and the advantages of the system. [Copyright &y& Elsevier]

Abstract: Since the implementation of “many textbooks under one guideline” in China''s basic education, Chinese language teaching materials are like a hundred flowers in bloom, various versions of the primary school language teaching materials are endless. This paper studied on three sets of national Chinese language textbooks and Five Provinces/Regions New Standard of the Tibetan primary school textbooks (volume1-12). This paper did a comparative analysis of word using and selection, including text selection, word types of different grades and the only word-using statistics etc., trough the statistical measurement method in order to explore the science and efficiency of teaching vocabulary design and provide the formulation basis, but also to provide comprehensive criteria for textbook evaluation. [Copyright &y& Elsevier]

Abstract: This paper focuses on the research and application of embedded database management system. The paper firstly analyzes the background of embedded database system, and then the features and classification of the embedded database are described in detail. Finally, by comparing and analyzing to several commonly used embedded database system, the paper gives out the application development of SQLite in ARM-WinCE, and analyzes the present application and future trends of embedded database management system. [Copyright &y& Elsevier]

Abstract: This paper summarized the defect of tree cover network and P2P resources search method, according to the characteristics of grid resources, based on A* algorithm, took search state as a node, built resources search state space. Through the implementation of the minimum cost of operation, to change the search status, to get the appropriate grid resources and to create the optimal search path being the guidance information to the next search course. In this paper a simulation experiments was carried out to compare search efficiency of several ways to search the grid resources. [Copyright &y& Elsevier]

Abstract: Compared to big satellites, small satellites are more sensitive to disturbances and likely to have more jitter due to their instability. In some of the acquired Beijing-1 small satellite panchromatic images, the artefact caused by jitter greatly reduces image qualities by bringing jagging to edges of the observed objects. In this paper, researches of the artefact are conducted with the jagged images. First, on theoretic bases and with image verification, properties of the Beijing-1 small satellite artefact are analyzed and a model is set up, then, accordingly artefact removal methods are brought up from similarity analysis of the image lines. Thorough discussions for usability of the methods are done and resulting in a conclusive strategy. Tests of the strategy with real and simulated artefactual images gain favorable results. Researches in this paper provide practical ground image processing solutions for settling of the artefact problem. Analyses of artefact properties can also provide assistance to searching for incentives of the artefact. [Copyright &y& Elsevier]

Abstract: The paper researched the process visualization of the data mining which is based on the latest researches and discusses in the word. The paper proposed the analyzer to change the parameter in order to participate and interact with the process of the data mining and put forward a kind of visualization model of the Apriori Algorithm depends on the comparison of a visualization methods in association rules. Therefore, The paper has played a positive role for technology research and application. [Copyright &y& Elsevier]

Abstract: At present the vehicle emission is the main resource of urban air pollution. The proper modeling of microscopic vehicle emission plays an important role in the accurate analysis and control of urban automobiles. In this paper, light duty vehicle selected as research object, the model of microscopic emission based on velocity and acceleration using BP neural network and bivariate regression analysis separately. The result shows that the two models are helpful to forecast and analyze the actual emission of vehicles on road. The model based on BP neural network is more suitable for the analysis of actual emission. The research in this paper can help propose the quantitative analysis and control strategy of urban emission. [Copyright &y& Elsevier]

Abstract: The problem of test point selection is important in the area of fault diagnosis and circuit testing. In this paper, a method based on immune clonal selection algorithm (ICSA) and integer-coded fault dictionary is proposed for selecting the optimum test points of analog circuits. The problem of test points selection is transformed into the selection of dictionary columns to isolate the rows by using integer-coded fault dictionary. Then, the ICSA-based method was used to find the optimum test points. In the end of this paper, the presented approach is illustrated by a practical example of analog circuit and statistical experiments. The experimental results indicate that the proposed method is easier to find the global optimum test points with acceptable time consumption. Compared with GA-based method, this method has fewer parameters to set. [Copyright &y& Elsevier]

Abstract: Rapid growth in wind power, as well as increase on wind generation, requires serious research in various fields. Because wind power is weather dependent, it is variable and intermittent over various time-scales. Thus accurate forecasting of wind power is recognized as a major contribution for reliable large-scale wind power integration. Wind power forecasting methods can be used to plan unit commitment, scheduling and dispatch by system operators, and maximize profit by electricity traders. In addition, a number of wind power models have been developed internationally, such as WPMS, WPPT, Prediktor, ARMINES, Previento, WPFS Ver1.0 etc. This paper provides a review on comparative analysis on the foremost forecasting models, associated with wind speed and power, based on physical methods, statistical methods, hybrid methods over different time-scales. Furthermore, this paper gives emphasis on the accuracy of these models and the source of major errors, thus problems and challenges associated with wind power prediction are presented. [Copyright &y& Elsevier]

Abstract: The double-loop strong coupling problem was existed in the model of some power devices under dq coordinate system. So the entirely decoupling control of UPQC is impracticability. A novel decoupling method is proposed in the paper and the entirely decoupling model of UPQC is achieved. But the paper is not detailed the design of control system. The UPQC can be controlled by open-loop manner and close-loop manner. Its series part can work as either controlled voltage source mode or controlled current source mode. So is the shunt part. Four detailed control strategies were proposed under two control manners and two control modes. The control results of four control strategies are simulated. It can be proved that every control strategy can realize the control goal and the comparison of them is detailed. [Copyright &y& Elsevier]

Abstract: Scientists in earth observation field often spend a lot of time on data preprocessing according to specific application targets. Using Web Coverage Service (WCS) and research on-demand data service model in spatial information system could help to improve efficiency and interoperability. It aims to integrate a large number of fundamental data pre-processing tasks into data access procedure, and minimize the time cost. This paper studies spatial data system to provide high level spatial data products to meet application request based on WCS standards. The paper introduces service module classification methods to adapter heterogeneous data exchange, and discussed data access service components and workflow control mechanism. It also conducted close examination of comparison study with traditional methods, analysis the performance results of the experiment. [Copyright &y& Elsevier]

Abstract: In this paper we give an overview of the situation of CO2 emissions in both Beijing and Tokyo and discuss and compare the causes for their emission changes according to decomposition based on both social activities and fuel varieties. We find that in order to enjoy a sustainable development, Beijing needs to learn from Tokyo especially in energy consumption area. At the end of the paper, the cooperation between these two metropolises is summarized. [Copyright &y& Elsevier]

Abstract: This paper uses T.aestivum, elytrigia intermedium and their distant hybrid progeny octoploid trititrigia as the test materials, and makes comparative analysis of the chromosome karyotypes of the three species with which have phylogenetic relationships by chromosome tablet method. The results show that: T.aestivum yannong15 has the karyotype formula as 2n=6x=42=30m+12sm (4SAT), and its karyotype is 2A; Elytrigia intermedium has the karyotype formula as 2n=6x=42=16m+20sm (4SAT)+6st, and its karyotype is 3B; Their distant hybrid progeny octoploid trititrigia shannongTE0521 has the karyotype formula as 2n=8x=56=36m (2SAT)+20sm (2SAT), and its karyotype is 2B. According to the karyotype evolutionary theory by Stebbins and the nuclear-based cladistic method, as well as analysis of the 4 traits of the karyotype, the results shows that the evolution of the octoploid trititrigia is in the middle of its two original parents. It is in this paper gives the first report of the karyotype of octoploid rititrigia, and makes preliminary study on the chromosomes and genetic evolution relationships of octoploid trititrigia and its original parents. [Copyright &y& Elsevier]

Abstract: The production of electricity from solar radiation is a direct process. Solar energy is not very dense, it is necessary to concentrate it to produce exploitable temperatures usable for the production of electricity. The radiation may concentrate on a point or on a line, where thermal energy is transferred to the heat transfer fluid. The intensity of concentration is defined by the concentration factor, the more this one is higher, the more reached temperature will be important. In this paper two optical technologies which showed promising results were compared, the first one is the Fresnel mirror and the second one is the parabolic trough. These two technologies are based on linear solar concentration. The main objective of this paper is to report the performance of these technologies by means of numerical analysis. A methodological analysis to design and evaluate the technical feasibility for the use of Fresnel mirror or parabolic trough in a Concentrating Solar Power (CSP) system has been carried out. The influence of ambient conditions and the percent of different types of energy loss, etc., are analyzed. An application on a site, in the south of Algeria (Hassi Rmel), is done. In this site, a project of hybrid natural gas/solar power plant with parabolic trough technology will be inaugurated before 2011. [Copyright &y& Elsevier]

Abstract: Basing on the questionnaire for experts, this paper builds an evaluation index system of the mining industry competitiveness in Xinjiang, and evaluates the mining industry competitiveness by using the principal component method. The conclusions are that the mining industry competitiveness of Xinjiang is ranked the first in western China .and there are some problems existing in Xinjiang, such as unperfected frustration, poor management of mining. Finally, this paper gives suggestions on enhancing the mining industry competitiveness of Xinjiang from three angles. [Copyright &y& Elsevier]

Abstract: This paper presents a summary of the main international and national regulations for geologic storage of carbon dioxide. The international group includes the EU Directives, London Convention, and OSPAR. For the national regulations, three countries were covered in this study: United States, Canada, and Australia. In addition to these regulations, a group of guidelines and best practice manuals were also included in this study. As discussion, although this paper recognizes that current legislations have contributed for the regulation of this technology, it is still necessary the development of new rules in other regions. Industry will not invest in large CCS plants without such regulations because of high CCS costs and large financial risks related to CCS. [Copyright &y& Elsevier]

Abstract: After 3 years and over one thousand person-months of effort, the FP6 CACHET project was successfully concluded in the first half of 2009. CACHET focussed on pre-combustion capture of carbon dioxide (CO2) from natural gas fuelled power generation and hydrogen (H2) production. Through a combination of experimental and paper studies, CACHET developed, optimised and evaluated four promising capture technologies: Advanced steam methane reforming (HyGenSys), Redox technologies (chemical looping), Metal membranes and Sorption enhanced water gas shift (SEWGS). This paper reports the technical and economic conclusions of the project and provides a look ahead to the future for each of the technologies and the challenges for full scale deployment. All technologies showed the potential to reduce CO2 emissions by more than 90% and the opportunity to improve the energy efficiency compared to the state-of-the-art technology. [Copyright &y& Elsevier]

Abstract: This paper offers a broad summary of the most common risk assessment methodologies for the geologic storage of carbon dioxide. We believe it is valuable to compare these methodologies, particularly in the areas where they lead to similar conclusions. The objective of this paper is to provide a better understanding of the current similarities and differences of these proposed methodologies. Since CCS was proposed as a mitigation option for reducing anthropogenic CO2 emissions, several attempts have been made to study the potential risks of long-term storage of CO2 in geological formations. Various worldwide projects have tried different industrial methods adapted to GSC. In spite of these efforts, currently there is no standardised method or set of methods for evaluating risk and/or uncertainty for GSC projects. Application or adaptation of advanced industrial quantitative risk assessment methods seems not convenient at this point because of lack of specific data. The development of frameworks and qualitative methods looks the most trustable for current projects. [Copyright &y& Elsevier]

Abstract: This paper presents the results of ASPEN simulations of a carbon-dioxide (CO2) removal and recovery plant that captures CO2 from a 500 MWe (net) conventional coal-fired power plant flue gas stream. At a constant CO2 recovery rate of 86.5% by weight, the performance of aqueous ammonia solution as an alternative to various aqueous amino solvents (MEA, AMP and MDEA) is compared in terms of the process scenarios, solvent loadings and overall energy consumption. The overall mass transfer co-efficient and CO2 loading data generated for aqueous ammonia solutions using a laboratory scale wetted wall gas-liquid contactor are also presented. The ASPEN simulation results in conjunction with the laboratory data show, that capturing CO2 from coal-fired power plant flue gas, using aqueous ammonia solvent, will require ammonia concentration no more than 5% by weight and absorber temperature 10 ∘C or lower, if the vapor phase ammonia losses are to be contained and the precipitation of ammonium bi-carbonate in the absorber is to be avoided. Under such an operating scenario, the aqueous ammonia based CO2 capture process has overall energy requirement comparable to the conventional 30% by weight aqueous MEA based process. The ASPEN results further show that 30% by weight AMP based process has the lowest overall energy requirement among the solvents considered in this paper. [Copyright &y& Elsevier]

Abstract: In this paper, hourly, daily and annual solar resource data derived form the latest SUNY solar model (version 3) using visible and infrared satellite data is analysed and compared with ground measured solar data from eighteen northern- latitude locations distributed all across Canada. The statistics of spatial and temporal differences between the two datasets obtained from the two versions of SUNY model, i.e., V1 and V3, are analysed for both global horizontal irradiance (GHI) and direct normal irradiance (DNI). SUNY V3 GHI and DNI data set is also compared to a dataset produced by the MAC3 cloud layer model for ten northern-latitude locations across Canada. The MAC3 model, using ground-based data, is the basis of the weather design input data files referred to in the current Canadian Model National Energy Code. It is also the model used for generating the CWEEDS (Canadian Weather Energy and Engineering Data Sets) long term hourly dataset, which is in turn used to derive the CWEC files (Canadian Weather year for Energy Calculations) also called typical meteorological years. CWEC files are used for design and analysis in various applications, including buildings heating and cooling as well as solar systems. Overall, results show that SUNY V3 has improved slightly compared to SUNY V1 in terms of estimating global and beam irradiance. Comparison of the SUNY V3 beta model with the MAC3 model seems to indicate that SUNY V3 model is resulting in better DNI estimates than those derived by the MAC3 model. Both SUNY V3 and MAC 3 models give similar estimates for GHI. [Copyright &y& Elsevier]

Abstract: The European Union has set a goal that the energy use in the built environment shall be reduced by 41% to the year 2050 compared to 2005-2006. This could introduce new opportunities for solar thermal systems in cold countries. In such countries, like Sweden and Canada, the economy in solar thermal collector installation projects is often spoiled by the fact that most of heating energy demand of the building occurs during periods when the available solar energy is low. The present paper investigates the performance of solar thermal systems subjected to different quota between space heating and domestic hot water demand (DHW). This study investigates the performance of a solar thermal system integrated to four different buildings with varying heating loads in two different locations, Sweden and Canada. Models of single family houses are created which are able to simulate the total heating demand with different heating demand profiles but the same DHW demand. Simulations are performed in TRNSYS, an advanced tool used to simulate transient systems. Results indicate that solar combisystems tend to generate more useful energy and therefore be more cost effective when installed in buildings with higher heating demands. [Copyright &y& Elsevier]

Abstract: Transparent façade collectors can provide solar heating and cooling and lead to primary energy savings even compared to an opaque wall. They can be simulated with a detailed physical model based on laboratory measurements. The demonstration installation in Ljubljana will provide extensive measurement data of transparent façade collectors in an outdoor environment. This allows a comparison with simulations performed with the model validated by laboratory measurements. This paper presents the demonstration installation and the measurement system, which are based on the new modelling abilities and focused on the outdoor validation of such models. [Copyright &y& Elsevier]

Abstract: In this paper the comparison between the performance of a cross flow heat exchanger in wet and dry operation for air handling process has been investigated. In addition, a case study of application of the component to perform indirect evaporative cooling in a AHU was studied with the software TRNSYS.Using experimental data and an appropriate analytical method, energy saving performances of the system has been evaluated through the entire cooling season for a typical Mediterranean site. Results show that high energy saving potential can be obtained if the component is operated in wet operation in term of reduction of electricity consumption. [Copyright &y& Elsevier]

Abstract: Thermal energy storage (TES) devices, especially hot water tanks lose energy through the surface. To keep the energy loss low, TES are insulated with materials like expanded polystyrene or mineral wool. However, the insulation of small and middle-sized TES is not as good as it should be. With Vacuum Insulation Panels (VIPs), it is possible to reduce these losses by a factor of 6 to 10, compared to conventional insulation materials. This paper describes the possibility of using VIP for insulating TES. This leads to a reduction of the energy loss. [Copyright &y& Elsevier]

Abstract: Large solar thermal systems (LSTS) are a promising market segment for solar energy. However, the realization of LSTS is more challenging compared to smaller plants, in both technical and economical terms. Permanent monitoring, data evaluation and fault detection during the operation of LSTS has shown by Fink et al. [3] and Peuser et al. [13] to be crucial for ensuring optimal performance. The only cost-effective way for permanent surveillance of LSTS operation is to make use of a computer-aided tool that performs as many steps as possible in an automated mode. The R&D project ‘IP-Solar’ developed the scientific basis and the technical fundamentals for such a system. This paper presents the current state of development emphasizing the methodology of the operation diagnostics. In particular, the algorithm-based approach, its implementation and testing are described in detail. [Copyright &y& Elsevier]

Abstract: Water management is one of the major areas of interest in the fuel cell research community. Previous studies have shown enhancement in water management and fuel cell performance using a parallel flow field design including a metallic foam structure in the channels of the cathode flow field [1]. In this paper, metallic foams are used in a new geometry and are applied to both cathode and anode flow fields to improve water removal, reduce production costs, and enhance the overall performance. The metallic foam increases turbulent mixing in the flow fields which prevents the formation of a laminar boundary layer at the surface of the gas diffusion layer (GDL). The foam also serves as a moisture wick removing liquid water away from the GDL while maintaining the level of moisture required avoiding dehydration of the membrane. In this study, the performance tests are conducted at a variety of dew point temperatures to determine the water management properties of the metallic foam in the new geometry. The performance of the metallic foam will be compared to that of a standard serpentine graphite flow field. The major criteria will include performance at nominal voltage and current and high current stability. [Copyright &y& Elsevier]

Abstract: The Polymer Electrolyte Membrane Fuel Cell (PEMFC), despite being regarded as an ideal replacement to the internal combustion engine, is still not an economically attractive pri-mover due to a number of key challenges that have yet to be fully resolved; some of which include degradation to cell components resulting in inadequate lifetimes, specialised and costly manufacturing processes and poor gravimetric/volumetric energy densities. This paper presents a novel stack concept which removes the conventional bi polar plate (BPP), a component that is responsible for up to 80% of total stack weight and90+% of stack volume in some designs [1]. The removal of said component not only improves the volumetric and gravimetric energy density of the PEMFC stack but drastically reduces the cost of the stack by removing all costly manufacturing processes associated with PEMFC component machining while the functionality of the traditional BPP is still retained by the unique stack design. The stack architecture is first presented and then the characterisation of the PEMFC is shown over a wide range of operating scenarios. The experimental studies suggest that the performance of the new design is comparable to that of traditional stacks but at significantly less cost price. [Copyright &y& Elsevier]

Abstract: The gas diffusion layer (GDL) of the proton exchange membrane (PEM) fuel cell is a vital component in water management since humidification and water removal are both achieved through the GDL. Capillary action in the GDL porous structure enhances water removal from the cathode catalyst layer, and hence prevents flooding which blocks the pathways of the reactants to the activation sites. To improve the transport of water and reactants, GDL properties are varied by changing the geometry and the PTFE loading of the carbon fiber paper (CFP), both changing the internal wettability of the GDL. In essence, the wettability describes the interaction of water with the porous structures inside the GDL. The knowledge of the surface properties and pore structure is important to enhance water management in the cell. In this work, two ex-situ techniques are used to measure transport characteristics of GDLs, such as the internal wettability, pore size distribution and permeability. These measurements have been applied to different types of GDLs with different structures and PTFE loadings. The comparison between the results will determine the effect of material and treatment on the properties of GDLs which can provide basic insight into the two-phase flow in this porous layer. [Copyright &y& Elsevier]

Abstract: Understanding the heat transfer mechanism from the combustion gases to the walls inside an internal combustion engine is key in the search for higher efficiencies, higher power outputs and lower emissions. Current heat transfer modeling concepts have been reported to be inaccurate for hydrogen engines. To investigate the heat transfer mechanisms in a hydrogen engine, we have measured the instantaneous heat loss inside a spark-ignition engine at three locations. To determine the effect of the throttle position, compression ratio, ignition timing and air-to-fuel ratio in the entire parameter space systematically, techniques of Design of Experiments are applied. The experiment has been repeated for methane, gasoline and methanol to compare hydrogen with other fuels and to build a database for the development of a fuel independent heat transfer model. The paper shows that the effect of the engine factors is similar for all the fuels. However, the heat loss to the cylinder walls of hydrogen is only at the same level of that of the other fuels for very lean mixtures. The engine efficiency drastically reduces for rich mixtures as a consequence, indicating that a lean mixture in combination with boosting and external gas recirculation should be used to obtain high power outputs with high efficiencies for port fuel injected engines. [Copyright &y& Elsevier]

Abstract: In this paper five heuristic models for the estimation of the maximum power output of photovoltaic (PV) modules with different numbers of parameters (one/two/three/four) using irradiance and PV module temperature as inputs are presented. To validate the performance of the presented models, logged data of mono-crystalline and HIT modules from high-precision outdoor module performance testing in Singapore are used. Results show that the one- and twoparameter models have disadvantages at low irradiances. Two different types of three-parameter models show as good results as the four-parameter model and hence seem to be a good compromise between model complexity and accuracy. [Copyright &y& Elsevier]

Abstract: In this paper, a comparative analysis of three methods to determine the four solar cells parameters (the saturation current (Is), the series resistance (Rs), the ideality factor (n), and the shunt conductance (Gsh)) of the single diode lumped model from its dark curve is presented. These methods are based on Gromov, Werner, and Mikhelashviliet al. methods that were used to extract the Schottky diode parameters. These techniques have been adequately modified, extended to cover the case of solar cells and used to extract the parameters of interest from experimental I-V characteristic of a Poly-Si solar cell under dark condition. [Copyright &y& Elsevier]

Abstract: The paper presents the results of theoretical and experimental approach study on solid waste thermal-chemical treatment for power generation. Three main conversion processes were used: direct combustion, pyrolysis and gasification. When applied to large variety of wastes, the option for a certain treatment method (gasification especially due to process low stability) requires the knowledge of physical-chemical characteristics of the waste to be treated. Current debates on cost-effect of these young technologies compared to old incineration are mainly focused on biomass, especially wood under gasification conditions (using air). For atypical waste (MSW, industrial, food industry, farm) operation data or experimental results with respect to process global energy balance are not available for public or the information is restricted to general aspects. The experimental research focused on a large variety of heterogeneous waste (cellulose based, plastic, food industry, agriculture) to energy conversion efficiency. Based on experimental results the electrical power out-put was estimated for three main conversion chains using the mentioned processes. [Copyright &y& Elsevier]

Abstract: Since its discovery, electrical energy represents one of the most decisive fields in any technology. In this paper, a comparative study between fixed hysteresis band current control (HBCC) and adaptive hysteresis band current control techniques in speed drive system is presented. These techniques control the variation of output voltage of the three phase rectifier. The theory and analysis of both the conventional fixed-HBCC and the adaptive HBCC which are the control techniques that operate at any condition with variable and constant switching frequency, are respectively developed. At the end, the performance of such control technique has been observed and discussed thanks to a simulation study carried with Matlab Simulink environnement. [Copyright &y& Elsevier]

Abstract: The paper introduced image processing technology based on image segmentation about on-line threads images, and describes in detail image processing technology from image preprocessing, image gmentation, and threaded parameter test. Threaded images of on-line processing parts obtained are introduced as the key technology, Target edge extraction process from the segmented image are also recounted. At last, this article shows a comparison between actual machining parameters of screw thread and the standard parameter, provides the criterion for error compensation. [Copyright &y& Elsevier]

Abstract: In this paper, in order to increase the efficiency of solar energy collection in winter, a method to set the semi-fixed collector was proposed. The best angle of the quasi-fixed solar collector have be calculated and given in Daqing region. According to comparison and analysis, we find that the efficiency improved 8.3%; it will collect solar energy 410.46MJ per square more than fixed collectors every year. [Copyright &y& Elsevier]

Abstract: This paper describes FMS scheduling problem based on Petri net with the goal of minimizing makespan. A hybrid heuristic search approach for the scheduling is presented, which combine dynamic search window with best-first algorithm and backtracking search., In addition redundant markings can be eliminated to reduce the searched state space. We use the proposed method to search for an optimal schedule of an example with varied lot sizes for each job type considered. Comparison with previous work is given to show the proposed approach can generate an optimal solution, but with much less search time and memory space. This hybrid algorithm can be deal with large systems. [Copyright &y& Elsevier]

Abstract: With the formation of the tripartite-confronting coal logistics competitive situation among the ports around the Bohai bay in China, each port is confronted with intensive challenges. This paper firstly identifies a group of factors and some considerations that are required for evaluating the port coal logistics competency. The coal logistics competency of the main ports in the Tianjin and Hebei regions around the Bohai Bay in China are then investigated in detail using the qualitative method by analyzing their comparative advantages and disadvantages in this competitive environment. Competitive strategies are thus proposed for these ports respectively, which may be useful for relative practitioners. [Copyright &y& Elsevier]

Abstract: Building integrated photovoltaic (BIPV) systems bring forward many requirements to grid-tied inverters in these aspects such as generating efficiency, shading effects, harmonic & reactive current compensation and quick economical payback, etc.. This paper presents a multi-functional utility interface of BIPV systems based on cascade multilevel converter. It has two operating modes: one is operated as grid-tied inverter at normal insolation level and the other is operated as active power filter (APF) at very low insolation level or at nighttime. Compared with traditional inverters, cascade multilevel converter is much more efficient and suitable for utility interface of BIPV system because it has the merits of high efficiency, minimum switching frequency, low switching stress and EMI, approximate sinusoidal waveform voltage output with low total harmonic distortion (THD), modular structure and good dynamic stability. Simulation and experimental results have verified its feasibility and advantage. [Copyright &y& Elsevier]

Abstract: The back analysis principle and method for thermal conductivity of RCC is introduced in this paper, and a Jiang Ya RCC dam is cited as a building example, on the basis of prototype temperature data of dam, the mathematic model by Difference principle is founded, the thermal conductivity of RCC is obtained. The result is similar to the data which is received in the laboratory. The back analysis is proved credible. The back analysis for thermal conductivity, on the one hand, actual safety of the completed projects could be evaluated; on the other hand, the design and construction in progress may be optimized. the scientific foundation for optimizing the design and monitoring the running of dam is provided. And it is provided with some scientific value and practical significance. [Copyright &y& Elsevier]

Abstract: Biomass gasification is one of the highest thermal efficiency chemical conversion processes. Numerical simulation is an important tool for study on biomass gasification. In this paper, numerical simulation on biomass gasification technology at home and abroad are reviewed. At the same time, two commercial simulation softwares (Aspen Plus and Fluent) applicated in chemical process was mainly introduced, and both of them were analyzed and compared. Finally it was put forward that a better simulation result could be achieved for biomass gasification if applying Aspen Plus combined with Fluent. [Copyright &y& Elsevier]

Abstract: Ground-source heat pump (GSHP) is a renewable energy technology with the advantages of energy saving and environmental friendliness. This paper focuses on the energy efficiency of air-conditioning systems in public buildings in Tianjin. Three public buildings are chosen as case studies with different forms of cold & heat sources. A building with ground-source heat pump for heating and cooling, a building with electricity-driven refrigerating unit for cooling and centralized heat-supply network for heating, a building with direct-fired Li-Br absorption refrigerating and heating unit for heating and cooling are selected. Attempt is made to analyze the actual operating performance of air-conditioning system and evaluate the system energy efficiency in different buildings. The results show that ground-source heat pump air-conditioning system without adequate design and management is not always better than other traditional air-conditioning systems. [Copyright &y& Elsevier]

Abstract: Stress corrosion cracking is the major threat to the safe and stable operation of nuclear power plants, and the residual tensile stress is one of its major causes. For in-service nuclear power plants, the most effective means to prevent stress corrosion cracking is change the stress status of material surface by peening technology. Compared with traditional shot peening, laser peening has advantages of good directionality, good accessibility,easy to control,no residue,deeper compressed layer,and more suited to use in the maintenance of in-service nuclear power plants. In this paper, research and application of underwater laser peening technology in nuclear power plant maintenance are summarized. [Copyright &y& Elsevier]

Abstract: There are many methods available for Load frequency control in an interconnected power system. This paper deals with tuning of PID controller for Load frequency control. A two area thermal power system is considered for study. Both the areas are equipped with PID controller. Parameters of these PID controllers are obtained using Particle Swarm Optimization. A comparative study on tuned values has been presented to verify effectiveness. Ziegler-Nichols method is used for tuning of parameters for comparative study. The simulation results demonstrate the effectiveness of the designed system in terms of reduced settling time and oscillations. MATLAB/SIMULINK was used as simulation tool. [Copyright &y& Elsevier]

Abstract: In this paper we focus on the effect of the temperature on two different solar cell semiconductor materials, one of them is the GaAs based solar cell and the other one is the In0.2Ga0.8N based solar cell. After simulating and extracting the electrical parameters of these devices in various temperatures from ATLAS (the two dimensional device simulator software), we compare those parameters between two different solar cell materials so as to introduce one of them as a better semiconductor material working in high temperatures. [Copyright &y& Elsevier]