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Abstract: This paper investigates the transient behaviour of an oxygen mixed conducting membrane (OMCM)-based gas turbine (GT) power plant. Several operation and material constraints limit the operability of the power plant. For part-load operation two strategies are analysed: (i) reduction in mass flow of air to the GT in conjunction with reduced fuel supply to the afterburner while keeping the turbine exit temperature (TET) constant (TET control strategy), and (ii) reduction of fuel supply to the afterburner at constant air supply to the GT while the TET is allowed to vary (turbine inlet temperature (TIT) control strategy). Simulation reveals that this GT power plant shows rather slow dynamics because of the recirculation of large amount of gas. The OMCM-based GT power plant is compared to a simple GT power plant with respect to design, off-design as well as transient behaviour during load reduction. Information about controlled and manipulated variables in the GT power plant is given for the development of control strategy. [Copyright &y& Elsevier]

Abstract: Oxyfuel combustion is one of the promising technologies to enable CCS for new and existing coal-fired power plants. For retrofit applications, oxyfuel is an attractive option because it does not have major impact on the boiler-turbine steam cycle. This paper presents a case study for retrofitting oxyfuel combustion technology in large state-of-the-art power plants that are originally commissioned and operated in air-fired mode. The overall process design for the modified power plant is outlined; necessary modifications of relevant components are explained. The paper also discusses results of experiments and numerical calculations on combustion behavior in the furnace. Retrofit measures ensure that the power stations still can run under both air-fired and oxyfuel-fired conditions if required by regulations/market conditions. This provides additional operational and commercial benefits for the operator of the plant and reduces the technical risk of implementing new components and processes not yet proven in the power sector. [Copyright &y& Elsevier]

Abstract: Carbonate Looping is a promising post-combustion capture process involving the separation of CO2 from the flue gas of a coalfired power plant at high temperatures (600–700 ∘C) using the reversible exothermic CaO carbonation reaction and the endothermic calcination reaction of CaCO3. The core of the carbonate looping process is a dual fluidized bed reactor in which the CO2 acceptor material (CaO) is transported between the carbonator (CO2 absorption) and regenerator (CO2 desorption). Due to the heat requirements for the regenerator, the carbonate looping acts as a CO2 separation unit and an add-on power plant, thereby offering the opportunity for increasing the site electricity production while inflicting only a low electric efficiency penalty on the total power plant. However, the quantity and quality of the Carbonate Looping heat sources differ significantly from a conventional coal-fired power plant. This paper presents the design and simulation of the carbonate looping steam cycle for a large coal-fired plant. The simulation involves the coupling of the carbonate looping reactor model from Aspen Plus with the steam cycle in EBSILON Professional code which is a mass and energy balance cycle calculation program specifically tailored for steam cycle calculations. The resulting simulation includes penalty deduction for the Air Separation Unit and the CO2 conditioning unit, resulting in a net efficiency of 39.2% and while increasing the net power input from 1052 MWe to 1533 MWe, an addition of 481 MWe for the retrofitted power plant. [Copyright &y& Elsevier]

Abstract: Modelling CO2 storage in saline aquifers on a reservoir scale, for example, for feasibility studies and risk analyses is very demanding with respect to computational cost due to the complex geometries that need to be described and due to the diversity of interacting hydraulic, thermal, mechanical, and geochemical processes. In most cases it is not necessary to be able to describe all these processes for the whole simulation time period or for the entire model domain. Within this paper it is outlined how model coupling could help in reducing the model complexity and increasing model efficiency while the relevant processes are still taken into account. Since the work on this topic is at an early stage, this paper is restricted to a discussion of coupling concepts. [Copyright &y& Elsevier]

Abstract: Large scale geologic sequestration tests are in the planning stages around the world. The liability and safety issues of the migration of CO2 away from the primary injection site and/or reservoir are of significant concerns for these sequestration tests. Reservoir models for simulating single or multi-phase fluid flow are used to understand the migration of CO2 in the subsurface. These models can also help evaluate concerns related to brine migration and basin-scale pressure increases that occur due to the injection of additional fluid volumes into the subsurface. The current paper presents different modeling examples addressing these issues, ranging from simple geometric models to more complex reservoir fluid models with single-site and basin-scale applications. Simple geometric models assuming a homogeneous geologic reservoir and piston-like displacement have been used for understanding pressure changes and fluid migration around each CO2 storage site. These geometric models are useful only as broad approximations because they do not account for the variation in porosity, permeability, asymmetry of the reservoir, and dip of the beds. In addition, these simple models are not capable of predicting the interference between different injection sites within the same reservoir. A more realistic model of CO2 plume behavior can be produced using reservoir fluid models. Reservoir simulation of natural gas storage reservoirs in the Illinois Basin Cambrian-age Mt. Simon Sandstone suggest that reservoir heterogeneity will be an important factor for evaluating storage capacity. The Mt. Simon Sandstone is a thick sandstone that underlies many significant coal fired power plants (emitting at least 1 million tonnes per year) in the midwestern United States including the states of Illinois, Indiana, Kentucky, Michigan, and Ohio. The initial commercial sequestration sites are expected to inject 1 to 2 million tonnes of CO2 per year. Depending on the geologic structure and permeability anisotropy, the CO2 injected into the Mt. Simon are expected to migrate less than 3 km. After 30 years of continuous injection followed by 100 years of shut-in, the plume from a 1 million tonnes a year injection rate is expected to migrate 1.6 km for a 0 degree dip reservoir and over 3 km for a 5 degree dip reservoir. The region where reservoir pressure increases in response to CO2 injection is typically much larger than the CO2 plume. It can thus be anticipated that there will be basin wide interactions between different CO2 injection sources if multiple, large volume sites are developed. This interaction will result in asymmetric plume migration that may be contrary to reservoir dip. A basin- scale simulation model is being developed to predict CO2 plume migration, brine displacement, and pressure buildup for a possible future sequestration scenario featuring multiple CO2 storage sites within the Illinois Basin Mt. Simon Sandstone. Interactions between different sites will be evaluated with respect to impacts on pressure and CO2 plume migration patterns. [Copyright &y& Elsevier]

Abstract: Containment is a key factor of geological CO2 storage: small, localized leaks could have consequences to health and safety (e.g. CO2 accumulation in cellars) and the environment (e.g. drinking water pollution). On the other hand, large leaks could affect wide areas and large populations, and could reduce the overall economic and environmental benefit of the CO2 storage site and of Carbon Capture and Storage (CCS) in general. Containment potential over hundreds of years is affected by unknowns and uncertainties, and it is therefore appropriately dealt with in the framework of risk analysis. One way of estimating containment risk is to use quantitative simulators: if properly calibrated they can predict leakages through potential pathways and, if used properly in a probabilistic framework (e.g. through a Monte Carlo approach), can take into account uncertainties and produce probability distributions of CO2 leaks. This paper will discuss how different methodologies for estimating risk from probability distributions of releases of substances can be reconciled in a consistent, unified approach that can be rigorous or simplified according to the state of knowledge and the degree of detail required in the calculation. [Copyright &y& Elsevier]

Abstract: The main objective of the research reported in this paper was to address the uncertainties associated with coal seam reservoir performance during and after CO2 injection in order to establish a methodology for the design, prediction and risk evaluation of safe and environmentally sound CO2 storage in coal seam reservoirs. Full field scale simulations up to 1,000 years with over 140 permeability realisations and various swelling coefficients and sorption isotherms have shown that controlling the injection well bottomhole pressure ensures no overpressuring of the coalbeds or the caprock. Long-term leakage simulations with high cement deterioration and CO2 leakage rates have shown that the likelihood of a leakage of 1% of the total volume of CO2 stored over 1,000 years is low, and can be mitigated against through careful operational planning and reservoir management during CO2-ECBM and CO2 storage. [Copyright &y& Elsevier]

Abstract: Over the past three decades the oil and gas industry has developed full-system approaches for safe and cost-effective injection of carbon dioxide (CO2). Projects have been executed successfully that inject into formations spanning a full range of depths, reservoir quality, pressures and temperatures. Injection has been into both aquifers and hydrocarbon bearing intervals. Lessons learned about site selection, storage design and site monitoring are directly applicable to current and future carbon dioxide geosequestration projects. In this paper the focus will be on storage project field experience and simulation-based investigations of plume growth and migration in different geologic settings. Also discussed will be options to optimize well rates and location to maximize the storage volumes of CO2 injection. Safe, efficient and reliable long term storage of CO2 will require knowledge and observance of limits on cap rock fracture pressures, location of formation spill points and maximum rates of injection to mitigate adverse sweep related to gravity override of injected gas. Study outcomes and key design parameters for three different storage scenarios will be discussed. One will be a depleted oil field in an anticline structure connected to a regional aquifer; a second will be storage into a deep and lower quality aquifer underlying a gas field and a third will be assessment of potential storage in a large regional aquifer in pressure communication with active producing fields. By use of specific examples across a range of possible storage scenarios we will illustrate that site specific data combined with detailed dynamic modelling is very important to a complete appraisal of storage site integrity and capacity. The terms corporation, company, affiliate, ExxonMobil, Exxon, Mobil, Esso, our, we and its, as used in this material may refer to Exxon Mobil Corporation, to one of its divisions, or to the companies affiliated with Exxon Mobil Corporation, or to any one or more of the foregoing. The shorter terms are used merely for convenience and simplicity. [Copyright &y& Elsevier]

Abstract: This paper examines, with reservoir simulation, the impact of applying “best practices” and capitalizing on reservoir architecture to restrict CO2 plume movement and maximize reservoir storage capacity. Specifically, the paper explores the value gained from using horizontal CO2 injection wells and taking advantage of any existing shale “baffles” in conjunction with other reservoir characteristics that influence flow such as capillary pressure, pore volume trapping, and CO2 dissolution. Recent geologic and reservoir data collected from the Tuscaloosa Formation at the Mississippi Test Site (a Southeastern Regional Carbon Sequestration Partnership CO2 sequestration pilot test) will be used as the case study for evaluating alternative CO2 injection and storage engineering concepts. The Tuscaloosa Formation is a thick, porous, permeable, regionally extensive saline reservoir occurring throughout the Gulf Coast and is considered a high priority setting for large-scale CO2 storage. [Copyright &y& Elsevier]

Abstract: CO2 storage in depleted gas fields is attractive but gas fields are unequally distributed geographically and can be utilized only within a restricted window of opportunity. Therefore, CO2 storage in saline aquifers can be expected to become an important element of CO2 capture and storage (CCS) systems. CO2 storage in saline aquifers is studied in the European DYNAMIS project, where special attention was paid to the relation between the geological structure, geological properties and achievable injection rates. This paper presents the results from simulations of CO2 storage in two aquifer structures. One aquifer structure is located in the English sector of the Southern North Sea and one aquifer structure located in Northern Germany. The geological model of the Southern North Sea structure was built using existing knowledge of facies geometry and distribution from literature and well logs and the overall geometry from interpreted horizons. The distributions of properties like lithology, net-to-gross ratios, porosity and permeability were stochastically modelled to represent the braided and meandering river and fan systems within the Bunter Sandstone Formation. High-porosity and high-permeability zones model fluvial channels running through the reservoir. A different approach was chosen for the North German structure. Because there is no information on the facies or petrophysical parameter distribution of the aquifer, three different model scenarios were generated. One model was created with homogeneous properties throughout the aquifer. Two other model scenarios were generated allowing the porosity and permeability to vary within certain ranges. This was done using a sequential Gaussian simulation with the known mean, minimum and maximum values of porosity and permeability, respectively. Due to the size of the aquifer structures and computing limits, up-scaling of the geological model of the Southern North Sea was required. The up-scaling was aimed to retain as much as possible of the modelled geological features such as braided river and fan systems. Several reservoir simulations were carried out in collaboration between TNO and IFP to assess CO2 injection. Given the injection rate constraints, the aim of the injection simulations was to: [•] assess the achievable rate of injection; [•] study the migration and behavior of the CO2 in the reservoir; [•] assess the most appropriate location(s) for the CO2 injection wells using alternate injection strategies. The injection strategy is relevant especially for the Southern North Sea structure, where river and fan systems may results in high-permeability zones through the reservoir. Accessing such systems may significantly improve a reservoir’s value for CO2 storage. The effect of such systems on the injection rates is demonstrated. The reservoir simulations also demonstrate the injection rates that can be achieved in tight reservoirs as in the North Germany case, and the effect of spatial variability of geological parameters. This will show whether it is reasonable to assume spatial geological homogeneity, when data on the reservoir formation are scarce. [Copyright &y& Elsevier]

Abstract: This paper explores the potential role of CCS under different policy options in the Dutch electricity sector. A bottom-up simulation model is used to evaluate different policy scenarios. The results show that CCS plays only a moderate role for gradually rising CO2 prices. By using the scale advantages in CO2 transport already for the first CCS plants comparable to the level of large scale transport, the competitiveness of CCS is improved considerably. Furthermore, our results indicate that different policy options stimulate different types of CCS technologies. Finally, stimulating CCS and renewable energy sources simultaneously is more cost effective in the long run than stimulating solely CCS. [Copyright &y& Elsevier]

Abstract: The business case for investment in power plants with CO2 capture is greatly improved if they are able to accommodate uncertainty in future market conditions and variations in local operating requirements.. This paper will outline a range of operating modes that could be important in determining the value of power plants with CO2 capture from various stakeholder perspectives. Different quantitative techniques that could provide useful insights into plant value with flexible operation are discussed and some preliminary baseline results from a deterministic simulation are reported. [Copyright &y& Elsevier]

Abstract: The most promising process for Post Combustion Carbon Capture (PCC) is reactive absorption. For the design and scale-up of this process, reliable process models are needed. To achieve this, the models need to not only reliably describe the physical and chemical equilibria in the reacting systems but also to account for both mass transfer and reaction kinetics. Consequently, the models are complex and contain a large number of input parameters for describing fluid dynamics and physico-chemical properties. In order to assess the required quality of the input, the sensitivity of the simulation results to the parameters has to be known. This paper presents results from such a sensitivity study for a typical operating point of a PCC pilot plant with 0.3 g/g monoethanolamine (MEA) in water as the solvent. A rate-based model and its input parameters are introduced and describe the pilot plant results well. The most relevant input parameters of the model are systematically varied and the influence of that variation on the simulation results is monitored. Absorber and desorber are considered separately. The results are sensitive to most of the studied parameters. High sensitivities are found for the interfacial area, the Henry’s law constant and the enthalpy of absorption as well as for the parameters describing the equilibrium and kinetics of the carbamate formation and the amine protonation equilibrium. [Copyright &y& Elsevier]

Abstract: This paper illustrates the application of dynamic simulation for the development of CO2 processing plants which are part of oxyfuel power plants. It is shown how dynamic simulation models are used to study transient processes such as load changes and disturbances, to evaluate and improve process design concepts, and to develop control and operational strategies. Furthermore, key success factors for dynamic simulation, such as appropriate model visualization and an early integration into the engineering workflow, are discussed. In order to study the behavior of the entire oxyfuel process, the application of model reduction methods is proposed. This facilitates the integration of dynamic simulation models that were initially implemented using different simulation tools, into a common simulation platform. [Copyright &y& Elsevier]

Abstract: In the ongoing EU project CESAR (CO2 enhanced Separation and Recovery) one of the main tasks is to develop new promising solvent systems and test these in pilot plants. The aim of the present paper is to show the effect of two of the modifications employed at the Esbjerg pilot plant using the Cesar 1 solvent system. A model for the Cesar 1 solvent system has been developed and implemented in the CO2SIM simulator. By simulation it is shown that the effect of lean vapour re-compression is higher than the effect of inter-cooling even taking into account the extra compression work needed for the compressor. The combined effect of both modifications is slightly less for the Cesar 1 solvent system than reported for 30 wt% mono-ethanolamine. [Copyright &y& Elsevier]

Abstract: It is believed that a RSAT™ (Regenerable Solvent Absorption Technology) process is the most viable nearterm technology for post-combustion CO2 capture from power plant flue gas. The Babcock & Wilcox Power Generation Group, Inc. (B&W) has deployed a suite of research tools to evaluate and develop the CO2 scrubbing technology, including laboratory, pilot-scale, and simulation modeling capabilities. Since the construction and operation of test facilities require significant resources, it is essential to effectively utilize these research tools by choosing a scale-up approach which provides robust design data for a commercial process while minimizing the amount of experimentation required. The scale-up protocol used for RSAT CO2 scrubbing processes was rigorously developed using rate-based modeling concurrent with acquiring fundamental laboratory and pilot plant data for process validation. These development activities were not conducted in series but rather overlapped to yield an optimized commercial CO2 scrubbing process in a reasonable time frame with a high degree of design confidence . This paper presents the scale-up protocol used in evaluating the RSAT process which encompasses both laboratory and pilot-scale testing as well as rate-based modeling to achieve a commercial-scale RSAT process design. This document demonstrates the qualification of test data from a packed tower scale-up point of view. Solvent screening research activities recently conducted within B&W successfully demonstrate the scale-up protocol used for RSAT process development. The time and cost of process development can be significantly reduced through rigorous rate-based modeling in conjunction with laboratory experiments and pilot plant validation. [Copyright &y& Elsevier]

Abstract: A significant number of efforts are underway to develop and assess technologies that will lead to technically and economically viable routes to reduce the CO2 emissions of fossil energy systems, particularly coal-fired power plants. Developing technologies to reduce emissions from these sources is essential for controlling atmospheric levels of CO2 because of the widespread reliance on coal as an inexpensive and abundant energy source. Two major systems-level design challenges exist. The first is how to design new plants that incorporate CCS technology. The second is how to retrofit existing plants to capture CO2. Both design challenges can benefit from an optimization approach, which considers the application of multiple potential technologies and analyzes ways in which the whole plant-wide system can be integrated to increase overall efficiency. This paper will present a modular framework for the analysis and optimization of power generation systems with CCS that helps to meet these design challenges. In order to more completely understand the economic and operational tradeoffs associated with the various potential carbon capture technologies, and how they can be applied to new and existing plants, a unified, systemic framework has been developed to provide a common basis for evaluation. Given the complexity of the design problem and the fact that new technologies are continually being developed, this framework is modular in nature and incorporates algorithms for the selection, integration and optimization of carbon capture technologies for both new and existing plants. In addition to the framework itself, this paper discusses simulation modules representing various capture technologies and power plant components. The framework provides the means to link the various modules together in order to provide a holistic, systems perspective of plant wide operations. Results of analyses and optimization scenarios performed with the framework are also presented. [Copyright &y& Elsevier]

Abstract: The storage of CO2 in deep saline aquifers is due to the large available capacities and the common occurrence of these formations one of the major options for carbon dioxide sequestration. Besides the multiphase flow aspects geochemical, thermal and mechanical processes may alter the conditions within the reservoir as well as in the cap rock. Whereas single aspects of these processes can be investigated with experiments a multi-process simulator allows evaluating their combined consequences for the storage system over short and long time scales. In this paper the newly coupled software ECLIPSE-OpenGeoSys is presented that allows a combined simulation of multiphase flow, transport and geochemical reactions. ECLIPSE provides a fast and efficient solution for the multiphase flow whereas the open-source scientific software OpenGeoSys is used for calculating transport and geochemical reactions. This paper presents the code structure of the interface. Furthermore the coupled software is successfully applied to benchmarks [Copyright &y& Elsevier]

Abstract: As Coal-to-liquid project is in face of lot uncertainties largely due to the wide fluctuation of oil industry, it is unableto evaluate this project accurately via the traditional NPV analysis method. The paper tries to app ly real optionsanalysis approach to evaluate this Coal-to-liquid project, simulate the fluctuation of oil price by a designed softwareand also compare the operating value and the value of waiting to invest in this Coal-to-liquid project. [Copyright &y& Elsevier]

Abstract: The sustainable development of resource and environment is the main content of the scientific concept of development and it has become a necessary condition for harmonious society. This paper builds an ecologicaleconomic system model containing natural capital by employing an endogenous economic growth model with natural capital and environmental protection investment, then analyzes the model''s dynamic behavior and imitates the behavior. At the same time, this paper discusses how the economic output is imp acted by the proportion of investment allocation in economic system. The results show that the complexity of ecological-economic system makes a huge difference in the system behavior in the short and long term. Only in the conditions of the certain proportion of environmental protection investment allocation, can the whole economy –ecological system grow steadily in long-term stability and develop sustainably. [Copyright &y& Elsevier]

Abstract: This paper takes Jiangsu province as an example, divides the zone of energy risks and uses GM (1, 1) and the combination of BP network model to forecast energy demand in this region.Finally, we adopt ARCEngine secondary development achieving the system simulation, and putting forward a strategic suggestion on energy problem of Jiangsu province. The study provides the scientific data support for making energy policy rationally, reducing the increasingly prominent phenomenon of energy demand and offer support for different levels in different departments. It can provide the scientific basis for risk prevention and comprehensive risk management plan. © 2011 Published by Elsevier Ltd. Selection and peer-review under responsibility of RIUDS [Copyright &y& Elsevier]

Abstract: As resource scarcity and environmental degradation has aroused global concern, new energy vehicles have become the developing trend of automobile industry all over the world. However, there is lack of incentive for innovations on more environmentally friendly automobile technology. This paper introduces endogenous and directed technology progress into the growth model to analyze the decision-making on R&D of environmental technology and concludes that automobile enterprises are less willing to engage in the energy -saving technological innovation as traditional fossil-fuel-based automobile technology is relatively mature. Therefore, it is necessary for the government to formulate some temporary supportive policies at the initial stage of the development of new energy automobile industry in China, to stimulate the initiative of vehicle manufacturers to innovate on environmental automobiles. [Copyright &y& Elsevier]

Abstract: Based on gray error GM (1,1) model, the paper proposed an improved error GM (1,1) model, and used this model to predict cultivated land in Yiyang. The results show that the improved error GM (1,1) model has high prediction accuracy, and better simulation results. And the results conform to the cultivated quantity change rule of Yiyang City, that is, the land area of Yiyang City, will appear in the next few years, modest growth trend, but the per capita arable land is still in the alert level of the United Nations. Therefore, protection of cultivated resources, rational utilization and protection of arable land are urgent tasks. [Copyright &y& Elsevier]

Abstract: This paper studies the diversified investment of China''s foreign exchange reserves from a new perspective of energy strategy. A model is designed to analyze investment strategy of Chinese sovereign wealth fund (SWFs) based on specific investment objective to maximize national welfare, regarding SWFs as one part of China''s energy strategy. The theoretical analysis and simulation suggest that the strategy sovereign wealth fund can increase the national welfare. As an instrument to hedge the risk of national economy, strategy sovereign wealth fund prefers to invest in the strategic industry such as petrol and metal industries aboard. The more the strategy sovereign wealth fund hedges the risk, the more the whole national welfare increases. [Copyright &y& Elsevier]

Abstract: According to the industry ecology theory, in the simulating flowing way between substance and energy in the nature ecology, to design the industrial production systems can use less resource reasonably and reduce emissions. As the most important large iron & steel enterprise in Inner Mongolia, applying the theory of industrial ecology, the Baogang Group gains great achievement in energy saving and emission reduction in recent years. Based on the industrial ecology theory, this paper mainly analyzes the practice of energy-saving and ejection-decreasing of the BaoGang Group. [Copyright &y& Elsevier]

Abstract: Industrial chains exhibit strong interdependency within industrial symbiosis network. When analyzing the interdependency effect among industrial chains, however, financial index is often ignored. In this paper, we will mainly focus on measuring the long-term interdependency effect through historical simulation and cointegration tests with financial data. A large-scale coal-mining group is studied empirically as a case to explain the framework of interdependency analysis among the industrial chains. The results display high degree of interdependency between production costs and marketing costs, and low degree of that between revenues and profits, which means high controllability of material flows within IS network and low controllability of sales, marketing. [Copyright &y& Elsevier]

Abstract: This paper shows the modelling of a domestic solar water heating installation. The results of simulations performed on daily basis for a solar system (collector with surface of 2 m2 and a storage tank of 200 litres), operated in Constantine (Algeria), which provides hot water for heating. The installation consists in a solar flat collector, a water storage tank, a source of auxiliary energy and radiators. We analyse more accurately the influence of the thermosiphon-flow rate and consequently the stratification degree of the tank on the water heating system performances. The interest of this study resides in the approach used to model the tank and in the analysis of the number of the nodes used on the gained energy. [Copyright &y& Elsevier]

Abstract: Heat pump systems can be found in high number of applications. One of these is the production of domestic hot water. This paper presents a quasi-steady state simulation model to predict the performance of a simple air source heat pump water heater (ASHPWH). The mathematical model consists of submodels of the basic system components, namely, evaporator, condenser, compressor, and expansion valve. These submodels were built based on fundamental principles of heat transfer and thermodynamics. The model was coded into MATLAB software and used to predict system parameters of interest such as hot water temperature, evaporating and condensing pressures, heat rejected in the condenser, electric power input, heating seasonal performance factor, and coefficient of performance. [Copyright &y& Elsevier]

Abstract: One of the most popular issues in the future power distribution is the quality improvement of microgrid and the development of smart grid (SG). Many applications operating at the microgrid level can be considered as smart grid functions. This paper proposes the application of Fuzzy Logic (FL) technique within microgrid energy system based on the most modern power conditioning equipment devices such as Unified Power Quality Conditioner (UPQC). This technique is working together with the microgrid to track the disturbance of the smart grid and improve the quality of the system with a high flexibility. Furthermore, a control methodology developed based on a simulation technique to maintain the output voltage of the microgrid. Finally, experimental results show the high performance of the proposed Fuzzy Logic controller (FLC) compare to the classical proportional integration (PI). [Copyright &y& Elsevier]

Abstract: This paper presents an investigation of a direct evaporative air cooler (DEAC) under Algerian climate, at the city of BECHAR. We carried out the theory and design of the DEAC. Simulation is done for an evaporative air cooler for three successive months June, July and August under TRNSYS environment. Measured weather data of the selected site are generated by METEONORM software. Result showed that the maximum depression of the dry bulb temperature reached is about 18.86°C and the Energy Efficiency Ratio (EER) is calculated. Evaporative cooling equipments work well in the hot and arid southern regions, which constitute practically the two third of the country. They have no impact whatsoever on the environment. Energy consumption is much less than in classical air conditioning units this is why these systems can be powered by solar photovoltaic panels. [Copyright &y& Elsevier]

Abstract: This paper reports on an experimental realization and field testing of a recently proposed solar fiber optic mini dish light concentrator connected to a hot water accumulator. The prototype dish is 150cm in diameter. In repeated test the collected and concentrated sunlight was transported in a one millimeter diameter optical fiber to a selective surface in the storage tank. This surface absorbs the radiation which remains trapped inside as it heat exchanges with tank fluid which temperature can reach 70°C. [Copyright &y& Elsevier]

Abstract: High fidelity Full Scope Operator Training Simulators play a key role in imparting plant related knowledge to the operating personnel in an effective way. It provides a platform for training the operators on normal and emergency conditions including all types of scenarios that would arise in any Nuclear Power Plant. The scenario based training helps the plant operator to handle a crisis in an efficient manner with the ultimate goal of safe and efficient operation of the plant. This paper discusses about the general description of PFBR Operator Training Simulator, modeling and simulation of various process models, the complexities involved etc. It also covers the associated process logics, controls, display of alarms and indications, malfunctions and transient incidents related to each process model, integration with other sub systems, individual process model testing, integrated performance testing and verification and validation of models. Simulation of process models are broadly classified into two main categories namely, External Models - that are developed in-house and ported to the simulator environment and Internal Models - that are developed using Simulation Tool. External Models are tested on the desk top for intended functioning and after obtaining satisfactory results, the models are ported to the simulator base wherein the Logical and Virtual Panel Models are built to represent a real system of the plant. Internal Models are built using the Simulation Tools and integrated with the External Models after testing. Combination of External and Internal Model represents the total plant and the performance testing is conducted in an Integrated Mode to qua lify the Process Models for training purpose. [Copyright &y& Elsevier]

Abstract: This paper investigates by means of finite-elements and SPICE simulation the further improvement of solar cell performance of PERC-type cells by introduction of industry-compatible solutions, such as a 120 sq. phosphorous emitter with a lower surface concentration than that of current 60 sq. standard emitters and the replacement of the silver screen-printed front-side metallization by narrow, dense electro-plated copper lines on lowly resistive Ti or NiSi contacts. [Copyright &y& Elsevier]

Abstract: Accurate simulation of a-Si:H / c-Si heterojunction (HET) solar cells is mandatory for acquiring a deeper understanding of device physics, better knowledge of material properties, and thus improving solar cells efficiency towards the 26% theoretical limit. The purpose of this paper is to provide relevant guidelines and to highlight key issues for accurate and physicallybased HET solar cells simulation. The need for a 2D simulation approach is demonstrated, together with an accurate description of the device optical performance. For the first time, a unified set of models and material parameters is proposed for reproducing experimental IV characteristics under illumination and obscurity conditions, considering state-of-the-art material parameters and localized defects. Finally, the key role of solar cell simulation is demonstrated for further device optimization. [Copyright &y& Elsevier]

Abstract: Laser-assisted diffusion of dopants is a promising way to realize selective emitter solar cells with a reduced number of technological steps. This paper discusses the simulation by finite element method of laser doping in order to optimise the fabrication process. A finite element method is used to solve the heat-transfer equation which describes the thermal effects and Fick''s second law which describes the diffusion of dopants. The phosphosilicate glass (PSG) layer that is produced during the emitter formation on p-type silicon solar cells is used as the doping source during the laser-assisted diffusion process. The influence of laser parameters and material properties are studied. Modelling results are compared to SIMS measurements of the phosphorous doping profile. A structure is discussed in the perspective of a self-aligned process for selective emitter fabrication, where the PSG layer is present underneath the silicon nitride (SiNx) passivation layer. [Copyright &y& Elsevier]

Abstract: This paper presents the effect of Series-Connected Transformer in DVR Applications. Sizes of DVR are 10 kVA, 380 Volt and frequency 50Hz. According to the DVR operation, the comparison of with and without series-connected transformer is studied. To shows that without transformer can be operated better than with transformer. Operation of with transformer will have an impact on the phase shift and voltage drop. The simulation results show that the magnitude of load voltage without the transformer about 1.0 p.u. (per unit) more than with transformer. Moreover, it has not effect of phase shift and no voltage drop. Therefore, it can be ensured that the effect of transformer, that occurred on results has to consider for DVR applications. In addition if build the prototype can be reduced cost of transformer. [Copyright &y& Elsevier]

Abstract: In order to apply cockroach swarm optimization (CSO) algorithm to more function optimization and improve its accuracy, this paper improve CSO by modifying chase-swarming behavior of cockroach, and apply the modified CSO to optimize several Benchmark Problems. The results of simulation experiments illustrate that modified CSO has stronger convergence performance and highly-accuracy optimization results compared with Particle Swarm Optimization (PSO) and Chaotic Particle Swarm Optimization (CPSO). [Copyright &y& Elsevier]

Abstract: Substation noise issue is popular problem which people always focus on. In this paper, the modal and harmonic response analyses have been processed on the main equipment reactor of the 220KV substation by finite element software ANSYS. The main reason for its vibration is pointed out and the simulation results with the equipment close to the measured value. Based on it the new vibration isolation system was designed. Compared with the original device, vibration and noise reduction was found to achieve the purpose, this method is practical, accurate, reliable, and has engineering significance. [Copyright &y& Elsevier]

Abstract: Computational models of driving behavior developed based on a cognitive architecture can provide better scientific understanding of driving, simulate driving behavior, quantitatively predict possible interference of in-vehicle tasks, and thus help develop human factors guidelines and tools for in-vehicle systems design. Driver lane changing is a common activity in driving. Therefore, modeling driver lane changing with a cognitive architecture should be an important component of cognitive models of driving behavior. In this paper, we develop a computational model of driver lane changing control with the Queuing Network-Model Human Processor (QN-MHP) cognitive architecture based on neuroscience and psychological findings. The simulation and experimental results from lane changing on straight and curved roads suggest that this model can perform the control process of lane changing well and the model''s control process is consistent with that of drivers. [Copyright &y& Elsevier]

Abstract: In the present paper, a new CA-based model considering the following car horning is established and is analyzed in great detail. Firstly, how the following car horning can influence the traffic system is discussed. Secondly, by applying the cross-covariance method, proper parameters are indicated to explore the phase transition features of the model. The results show that the model proposed in this paper can simulate complex and realistic traffic phenomena. [Copyright &y& Elsevier]

Abstract: This paper presents a nonlinear model of a catamaran-style Autonomous Surface Vehicle (ASV) thrust with twin fixed propellers, which are driven by DC electric motors. A total model including resistance of boat body, propulsion force and driving characteristics of motor is established. Response for a full range of the ASV motion is simulated according to the model, based on which the performance of the ASV is discussed. Experiment results from sea test are in accord with the ones from simulating, which validate the nonlinear model. Compared with the classical linearized models, the advantage of the nonlinear model lies in convenience for dealing with system response for the full range of ASV motion. [Copyright &y& Elsevier]

Abstract: This paper presents a flexible CAB (configurable analog blocks) topology for field programmable analog arrays (FPAA). A fully differential difference amplifier (DDA) was used as the core circuit block in the CAB. The CAB is mainly composed of DDA, several programmable capacitor arrays (PCAs), and programmable resistor arrays (PRAs). The DDA_based circuits often provide high input impedance and simple external circuitry, and therefore are competitive to the opamp-based circuits. The proposed DDA_based CAB has been designed in a 0.35μm CMOS+EEPROM process. Simulation results show that the presented CAB is powerful enough to implement the fundamental and certain complex analog functions, for instance, integrator, filters, subtracter etc. [Copyright &y& Elsevier]

Abstract: Most of the fuzzy classifiers are created by fuzzy rules based on apriori knowledge and expert''s knowledge, but in many applications, it''s difficult to obtain fuzzy rules without apriori knowledge of the data. To solve this problem, a new way of creating Mamdani fuzzy classifier based on Mamdani fuzzy logical system is proposed in this paper, and the new fuzzy classifier is improved with the genetic algorithm further. The result of data simulation with Iris data shows the new Mamdani fuzzy classifier has minimum number of features, minimum number of fuzzy rules and better precision. [Copyright &y& Elsevier]

Abstract: Orthogonal frequency division multiplexing (OFDM) suffers from a high peak-to-average power ratio (PAPR).Tone reservation is a popular PAPR reduction technique that uses a set of reserved tones to design a peak-canceling signal. In this paper, the performance and complexity of clipping noise guided, complex base-band active-set methods based on tone reservation for PAPR reduction are analyzed and simulated. The simulation results show that the two clipping noise guided methods, the adaptive scale method and constant scale method, have better performance than complex base-band active-set methods. Furthermore, the complexity of the constant scale algorithm is lower than the adaptive scale and the complex base-band active-set algorithm. [Copyright &y& Elsevier]

Abstract: This paper proposed a software solution of GPS receiver quality inspection system based on the Simulated Signal Source. The GPS receiver quality inspection software of friendly man-machine interface, high efficiency and good stability is developed using language C#. Firstly, the functions of system are analyzed by the objective-oriented means. And the block diagram of whole software structure is given. Then the main function, data flow diagram, design effect and testing process of the Mathematical and Simulation Subsystem, Management and Control Subsystem and Testing and Evaluation Subsystem are detailed introduced. At last the quality inspection report on the Novatel dual-frequency receiver proved that the GPS receiver quality inspection software system is of good openness and high transplant ability. [Copyright &y& Elsevier]

Abstract: In order to study the satellite''s moving features and the size of stable reigns around the center equilibrium points of asteroid, 1:1 resonant orbits theory are applied in this paper. First the Hamilton function described by Delaunay variable is simplified to Schubart standard. Secondly the simplified mathematical model is used to discuss the form of orbital motion, vibration period of satellites which locate orbit the asteroid''s equilibrium points and the relationship between each other. And then Asteroid Vesta is taken as a simulation example to verify the correctness of these conclusions above. Finally, exploiting the properties of energy integral of Schubart standard, the formula of deducing the radius of stable region around the center points is given, which is also applied to analyze the properties of orbital motions both inside and outside of the stable region. The research in this article not only can help us better understand the equilibrium points of asteroids and the dynamical environments in the vicinity of which but also can it supply theoretical basis in designing the orbit around the equilibrium points around the asteroid. [Copyright &y& Elsevier]

Abstract: In this paper, a new BP neural network classifier was constructed and optimized by Genetic Algorithm, first, the BP neural network was improved by using genetic algorithm to train the initial weights values of the BP neural network, second, a new classifier was constructed based on the new BP neural network optimized by Genetic Algorithm. Finally, data simulation experiment was taken and the result of data simulation with famous IRIS data shows that the new BP neural network classifier improved by the Genetic Algorithm has higher accuracy of classification and greater gradient of convergence than the BP Neural Network classifier which Proposed in literature . [Copyright &y& Elsevier]

Abstract: This paper studies the vehicle rollover warning based on the vehicle running state parameters which are easy for collecting. By taking advantages of neural network and support vector machine, this paper analyzes the probabilities of the vehicle rollover in the scenario of single lane change and establishes a warning model which could predict the rollover 0.4seconds in advance for a particular type of vehicle. According to the validation experiments on Ve- DYNA which is a vehicle dynamic simulation software, the results validate the warning model''s good performance with the maximum error as 0.04 second and no missing cases which indicates its validity for rollover warning. [Copyright &y& Elsevier]

Abstract: In this paper, we analyzed the multi-instance multi-label (MIML) learning structure which proposed by Zhou. In realworld, there are many problems mentioned in complicated systems, traditional MIML structure would only consider the initial and final state, when facing with more tanglesome system, the lack of middle decision layer will affect the whole capability of system. The new proposed structure – layered MIML frame will help us to solve these tasks more easily by middle layer with reward mechanism. Finally, we use RoboCup Simulation 2D as platform to verify our frame and algorithms, the result shows the frame presented is valid and well-performed. [Copyright &y& Elsevier]

Abstract: Bone drilling is a fundamental skill for orthopedic surgeons, especially for spinal orthopedics. In this paper, a framework is presented for the simulation of spinal bone drilling process and a prototype simulation system for training of skull-bone drilling is introduced. In the simulation process, a user can drill a virtual spinal bone with Falcon feedback device with felling of force and vision of the virtual hole in order to improve the education effects of the residents and practical abilities. [Copyright &y& Elsevier]