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Abstract: A lot of work has been done in the field of multi-valued model checking home and abroad. But some research works are not perfect. Some problems in the semantic definitions of temporal operators and corresponding model checking algorithms are found in the paper “Model Checking Using Partial Kripke Structure with 3-Valued Temporal Logic”. Some counterexamples are given to show these errors. On the basis of the discussion, some sound semantic definitions of temporal operators and correct algorithms of model checking for some temporal operators are given. [Copyright &y& Elsevier]

Abstract: In a future energy generation market, the storage of energy is going to become increasingly important. Besides classic ways of storage, like pumped storage hydro power stations, etc, the production of hydrogen will play an important role as an energy storage system. Hydrogen may be stored as a liquefied gas (LH2) on a long term base as well as for short term supply of fuel stations to ensure a so called “green” mobility. The handling with LH2 has been subject to several recent safety studies. In this context reliable simulation tools are necessary to predict the spill and spreading of LH2 during an accidental release. This paper deals with the different boiling regimes: film boiling, transition boiling and nucleation boiling after a release and their modeling by means of an inhouse-code for wall evaporation, which is implemented in the commercial CFD code ANSYS CFX. The paper will describe the model, its implementation and validation against experimental data, such as the HSL LH2 spill experiments [1]. [Copyright &y& Elsevier]

Abstract: A detailed mathematical simulation and experimental investigation of airflow in solar chimneys is studied in this paper. Several experimental studies were carried out on the solar chimney; their choice depends on the parameter of the design and the thermal performances for different geometrical configurations. The experimental tests show that the field speeds in the chimney is influenced by the width of the channel and also of the angle of inclination of the chimney. Therefore, investigations have been carried out in this paper to find the effect of inclination on the performance of solar chimney in Ouargla Province, Algeria. The simulation of this problem is implemented into the commercial CFD code Fluent 6.3. 26. The conservation equations of mass, continuity and energy are solved by the Finite Volume Method. The validation of the results is presented. An good agreement between the experimental results and simulation ones is observed. [Copyright &y& Elsevier]

Abstract: This paper uses Diffuser Augmented Wind Turbine for reference. According to the characteristics of ocean current movement, this paper gives several dome model programs for the straight blade vertical-axis tidal turbine. Make use of it to increase its output power. This paper gives several dome model programs for the straight blade vertical-axis tidal turbine. And optimum scheme is chosen by numerical simulation. [Copyright &y& Elsevier]

Abstract: The paper adopts standard k−ɛ turbulence model and other mathematical models, and completing the blending lignite combustion numerical simulation of 600 MW boiler of one power plant. Three conditions were simulated in this paper, and these three conditions were compared and analyzed, the basic conclusion is consistent with the test. The result shows that the combustion character of blending lignite is lower than burning soft coal. Burning lignite shows a decline furnace temperature, and the simulation results are consistent with the experimental results. Pay attention to adjust the reasonable operating manner, and the operation is safety and economic. At the same time this paper also provides a useful reference for researching tangentially fired boiler furnace process. [Copyright &y& Elsevier]

Abstract: With the widespread popularity and application of the network, the new words appear on the internet one after another. The research on the generation of new words on the network has been a revelation to the innovation environment cultivation. This paper summarizes the type and the producing process of the new words on the internet, analyzes the innovation environment of new words on the network, and builds an innovation environment model of new words on the network from network environment, the structure of the internet users, the entertainment and virtual features of the network communication. On the basis of it, the paper discusses the innovation environment building in the context of the network and proposes to create a broad-based participation, free exchange, and timely sharing and dissemination innovation environment. [Copyright &y& Elsevier]

Abstract: Mobile Cloud Computing has become as a new IT paradigm because of the growth of mobile device like smartphone and appearance of Cloud Computing environment. This mobile cloud environment provides various services and IT resources according to users’ requests, so an effective management of service and IT resources is required. Hence, this paper designs a context model based on ontology in mobile cloud computing in order to provide distributed IT resources and services to users based on context-awareness information. As the context model proposed in this paper uses context-aware information, it enables to provide more accurate personalized services and manage distributed IT resources. [Copyright &y& Elsevier]

Abstract: By the use of modelling software, this paper set up the three-dimensional physical model of single-stage turbine and guided it into the pre-process software. After meshing the turbine flow channel, simulating the mud flow characteristics in Turbine with CFD, and calculating the pressure drawdown at the inlet/outlet and the pressure distributions in single-stage turbine. Such results indicate that the pressure drawdown of single-stage turbine is influenced by the mud discharge capacity, drilling fluid density and viscosity. The pressure drop increases with the augment of mud discharge, which is approximately linear. There are significantly positive correlations between the pressure drawdown and the increase of mud density. The research in the paper provides reliable guidance in turbine flow channel design and the drilling technological parameters optimizing. [Copyright &y& Elsevier]

Abstract: Because of burstiness, weak economy, time-uncertain of emergency logistics system, the paper constructs the operation model and its evaluation index system for emergency logistics system. In view of the imperfection of subjective determining index weight method in traditional evaluation, the index weight coefficients are determined by information entropy method of combining subjective judgment with objective evaluation. Then the fuzzy clustering and information entropy to determine the weights are used into emergency logistics system reliability evaluation. Finally the paper obtains a specific solution steps based on an example. [Copyright &y& Elsevier]

Abstract: Robot is widely used in industrial domain and pose accuracy of end-effector is an important indicator for judging robot performance. Calibration is a necessary for operating industrial robot and an effective and efficient means of accuracy improvement. This paper describes the development of a calibration procedure for a five degree of freedom serial robot using the laser tracker. The main goal of this paper is to utilize measurements relative to the end-effector of the robot to compensate errors. The robot kinematic model is computed to help identify the deviations. Robot parameter deviations can be identified so that the nominal parameters can be corrected. The experimental results are validated effectively. [Copyright &y& Elsevier]

Abstract: A large AC generator is an important component of the power system. Researches on the AC generator relaying for the next-generation ECMS and an efficient operation of protection control system are necessary. These require developments on detailed generator modeling and internal fault analysis, and prototyping for multifunctional IED device dedicated to next-generation production. In this paper, over-excitation relaying algorithm is one of the main protection elements which have an important role in DGPS(Digital Generator Protection System), was proposed. This paper first briefly introduces a principles of over-excitation and DFT-based gain compensation algorithm was adopted for the frequency measurement. Subsequently, protection scheme of over-excitation was presented. The 765[kV] modeling data of South Korea using EMTP-RV was used for simulations. The simulation result of over-excitation relaying are also provided. [Copyright &y& Elsevier]

Abstract: The numerical modeling of High Temperature Air Combustion (HTAC) could correctly predict the flame and emission characteristics so far, however, the precision is not satisfactory. In this paper, a parameter-modified Eddy-Break-Up (EBU) model with a three-step reaction scheme was used to simulate the HTAC process in a furnace of 2m ×2m×6.25m. Reynolds stress model (RSM) is used for the computational fluid dynamics (CFD) simulation. Comparison between experimental data from published papers, the original and modified EBU combustion models demonstrates that a smaller coefficient ‘A’ in the volumetric fuel consumption rate of the EBU model could improve the modelling precision. When ‘A’ is modified to be 1 other than its original value, 4, in the EBU model, the modeling could give improved results of the local distribution of CH4, temperature and NO emission. [Copyright &y& Elsevier]

Abstract: Multi-beam bathymetry sonar is one of the current important equipments for seafloor bathymetry information detection. This paper extends the phase center cross-correlation method (PCCCT) which is successfully used in a 3- row bathymetric sidescan sonar to multi-beam bathymetry sonar, and a 3-subarray Direction-of-Arrival (DOA) estimation method based on phase difference measurement is proposed. A comparison with the split-beam DOA estimation method which is commonly used in multi-beam bathymetry sonar is employed. The paper analyzes the basic principle of the new method in details, and derives its mathematical model expression. The performance analysis is accomplished in theory. Computer simulation data is processed, and the results show that the 3-subarray DOA estimation method is effective and practical for multi-beam bathymetry sonar. [Copyright &y& Elsevier]

Abstract: This paper tries to widen the notion of adaptation to take account of bidirectional adaptations between the context and activities so as to ensure not only the activity adaptation but also the adaptation of the context of the user to the requirements of the activities. What''s more, this paper presents a bidirectional adaptations workflow management algorithm (BAWM) for the route-choice of campus navigation, which can dynamically adjust workflow execution behaviors based on current context information and the user activities. This paper also manages to show that the correctness of the BAWM algorithm by formulating it as a Petri-net model. [Copyright &y& Elsevier]

Abstract: This paper introduces the craniofacial data acquisition, three-dimensional reconstruction, the method of the distance measurement, angle measurement, area measurement and volume measurement of the threedimensional model of craniofacial, based on the project of ‘The Tibetan craniofacial databases and quantitative analysis method’. The innovation of the paper is adopting a standard part in the process of data collection so as to provide a reference for measurement and error analysis. [Copyright &y& Elsevier]

Abstract: Bayesian method is good to improve precision and earn cost, but it would be constrain to use in situation of field data be different with prior data in overall distribution, as generally change model or give up Bayesian method in this situation. In this paper, with consideration of physical connection of prior data and field data, thoughts of using Bayesian fusion method in different overall distribution between prior data and field data was developed, which was from 3 conditions of function of prior data and field data: distribution form and parameters were known, parameter had prior distribution and only distribution form were know. At last, an example was given to explain the usage method promoted by this paper. [Copyright &y& Elsevier]

Abstract: The efficiency and maturity of the information management system development environment in embedded Linux OS are not convenient for programmer. This paper synthesizes the technologies including memory-share, miniGUI and expat, and presents a complete information management system frame in embedded Linux OS. The reference model in this paper satisfies the design and implementation of an information management system based on embedded Linux OS. [Copyright &y& Elsevier]

Abstract: Currently, the cloud computing is welcome in scholars and enterprise, because of its good features such as low investment, easy maintenance, Flexibility and fast deployment, reliable service. However, when the cloud computing is implemented, the security and credibility is one of the biggest obstacles. In cloud computing, users directly use and operate software of cloud service providers, operating system, even programming environment and network infrastructure, so the impact and breakage users caused for cloud software and hardware resources more serious than the current Internet users to share resources. So whether the behavior and behavior subject is credible or not, how to authenticate and control user behavior, these are important parts of the cloud computing study. This paper presents the concept of user behavior authentication, discusses how to authenticate and control user behavior in the cloud computing environment according to the user''s behavior, include establishment of behavior authentication set, mechanisms of behavior authentication and control, corresponding mode of Stochastic Petri Nets, False Negative rates and algorithm performance etc. Paper lays the theoretical and practical foundation for the real application of cloud computing. [Copyright &y& Elsevier]

Abstract: In order to monitor the specific information of Ed2k-based network, this paper, based on the currently P2P traffic identification and Ed2k-based network, established an initiative monitoring model in view of specific information eMule-based Ed2k network. This model, based on the specific information which to be monitored, Ed2k network adopts the initiative detection and pseudo-client technology to repeatedly detect Ed2k practical audience information, and then gets the audience information related with specific information. Then mathematically statistically analyzes the obtained audience information to determine the disseminative trend of specific information in Ed2k network; and provides data support for specific information pre-warning or forecasting. Finally, this paper proved the feasibility and effectiveness of the proposed monitoring model by the achieved system. [Copyright &y& Elsevier]

Abstract: With the Internet and virtual reality (virtual reality) technology, Web3D technology is generated; its aim is the Internet-based three-dimensional virtual world.VRML Virtual reality modeling language is the most widely used application on web3D three-dimensional scene description language. VRML''s shortcomings are just a description language with the lack of complex behavior and interactive programming support.Combined with the virtual environment, this paper establishes the integrated application of Java3D and VMRL build Web-based virtual environment application framework. Meanwhile, the paper also analyzes the technical features of VRML and Java3D, which gives VMRL and application in a virtual environment Jav3aD on some implementation details. [Copyright &y& Elsevier]

Abstract: In this paper, we propose an ear recognition system based on 2D ear images which includes three stages: ear enrollment, feature extraction and ear recognition. Ear enrollment includes ear detection and ear normalization. The ear detection approach based on Gentle Adaboost algorithm detects the ear part under complex background using two steps: off-line cascaded classifier training and on-line ear detection. Then Active Shape Model is applied to segment the ear part and normalize all the ear images to the same size. For its eminent characteristics in spatial local feature exaction and orientation selection, Gabor-based ear is presented in this paper. Kernel Fisher Discriminant Analysis is applied for dimension reduction of the high-dimensional Gabor features. Then distance based classifier is applied for ear recognition. The experimental results on USTB ear database show effectiveness of the proposed approach. [Copyright &y& Elsevier]

Abstract: Many world natural heritages in China contain various protected areas, such as the nature reserve and the scenic park. In many heritage sites the heritage resource are not well protected and managed because of the existed problems in management, including lack of the chaotic of management aims, the complexity management structure, the nonconformity of management system. The effective management is the key to protect the world natural heritage. In order to seek the effective management model to manage the world natural heritage in China, it should learn from the international conversation system and protected manners of resources, the successful experiences of advanced national park management model in American and other countries. In this paper, taking the Jiajin Mountains Giant Panda Sanctuary as an example, the concept of national park management model was introduced to the world natural heritage in China. It examined the Jiajin Mountains Giant Panda Sanctuary national park management model by combining the Chinese national conditions. Firstly, the paper introduced the Jiajin Mountains giant panda sanctuary briefly. Secondly, it analyzed the conditions of protection and management in Jiajin Mountains Giant Panda Sanctuary and showed the existed problems of heritage management. Finally, it discussed the feasibility and necessity on national park managing the Jiajin Mountains Giant Panda Sanctuary. Therefore, it was carried on the useful exploration to constructer the national park management model of the world natural heritage with Chinese characteristic. [Copyright &y& Elsevier]

Abstract: Based on the research of the concept and structure of project complexity, the Construction System Complexity Concept Model (CSCCM) is built, considering the characters of construction project. In this paper, the behavior of the construction system is described in six angles of view, including engineering technology, project stakeholders’ organization structure, engineering task, engineering information, project objectives and project environment. The CSCCM built in this paper is the base of the development of Construction System Complexity Measurement Model (CSCMM) and using of the complexity theory to construction project management. [Copyright &y& Elsevier]

Abstract: Multiple resources leveling problem is a hard nut to crack. In this paper, ant colony optimization is employed to solve multiple resources leveling problem. First of all, this paper introduced the basic models, advantages and disadvantages, as well as the application of ant colony optimization. Then, the model of multiple resources leveling optimization was established. Finally, combined with the basic principle of ant colony optimization and the essence of multiple resources leveling, this paper design the algorithm for multiple resources leveling based on ant colony optimization, and put forward the optimization steps. [Copyright &y& Elsevier]

Abstract: Seismic peak ground acceleration(PGA) is one of the important factors for reflecting the potential earthquake risk. PGA attenuation model commonly used assumed mathematical model, the use of regression analysis to establish the relevant parameters, but the model itself invariance restrictions on the range and accuracy. This paper proposes the application of RBF neural network model predicted PGA attenuation, the steps of RBF network structure elements and parameters are analyzed. With example the research verify that the predictive value base on the RBF neural network model is more consistent with the actual value. The analytic method and process discussed in this paper can also be applied to calculate and draw up the seismic ground motion parameter zonation in different region. [Copyright &y& Elsevier]

Abstract: Based on the problem of underground vertical U-tube heat exchangers in ground source heat pump systems in Shenchi station of Shuohuang railway, the transient heat transfer physical and mathematical model of the soil and borehole temperature field is established. Finite element numerical simulation is made by virtue of MATLAB software. Through the method of numerical simulation, the paper analyzes the soil temperature, obtains the distribution of isotherms around the pipes and the scope of the heat transfer, and understands the heat transfer performance around the pipe intuitively. Based on the model and numerical solution, the paper analyzes the changes of temperature field about the soil around ground heat exchangers in different ways which involve geological conditions operating mode, layout, pipe depth, and pipe coupling interval situation, and then the dates are obtained to help the engineering design of ground heat exchangers. [Copyright &y& Elsevier]

Abstract: As a tool, Comprehensive Evaluation based on fuzzy matter-element model provides a way to calculate risks. This paper introduces the common theory of fuzzy matter-element model evaluation, puts up general procedures of risk evaluation based on fuzzy matter-element model evaluation, and establishes model of fuzzy matter-element model risk evaluation as well as comprehensive evaluation method based on fuzzy matter-element model. This paper, through a real project, analyses risks exist in the project of Caiyuanba Bridge in Chongqing from the view of proprietor with fuzzy matter-element model evaluation applied, and the results verifies the superiority and feasibility of the method and its good efficiency in project risk management. [Copyright &y& Elsevier]

Abstract: This paper focus on pricing methodology research about resources contain of non-use value. Reasonable and accurate assessment of resources plays an important role in the management of coastal zone. But valuation of resources that contain of non-use value is still unsatisfactory on its validity and reliability. This paper extends the study of pricing model, which based on Subordinate Function of resource price, to a forward step research to analyze of how the resources are priced by respondents. And there are three steps to reach this aim. A survey about shoal wetland price per year is conducted to citizens of Xiamen firstly, then the pricing results of respondent are disassembled to a series weights of factors through the resolution of fuzzy relationship equations. Finally, causality between characters of respondent and weights of factor are analyzed by means of multivariate correlation analysis. The study indicates that the “Knowledge about the resource” is the most influential character of respondent that impact on a resource pricing, while “Income” is the second of influential. And “Distance from the location of resource” has the least impact on the pricing. However, another finding is that none of the 5 characters are critical to a resource pricing. [Copyright &y& Elsevier]

Abstract: This paper proposes the way of specification by which the CM4AR can be formally described in the PiOZ. CM4AR (coordination model for architecture reuse),which is constructed and designed on the basis of architectural reflection theory, can provides the support for reusing software architecture and its constituents at design time. CM4AR is logically divided into meta-level and base-level. When CM4AR is used to support architecture reuse, the interaction between meta-level and base-level will occur and the two levels in the CM4AR must be consistent all the time. The consistency between the two levels is ensured by the correctness of causal connection between the two levels. In this paper we propose the formal specification for the CM4AR in order to characterize the causal connection between meta-level and base-level precisely. So there are three parts of the formal specification, including the formal specification of base-level, meta-level and interaction between two levels. The result of this paper is the foundation for proving the correctness of causal connection between two levels in the future. [Copyright &y& Elsevier]

Abstract: this paper gives them some properties. This paper firstly introduces rough logic, and proposes factorization of model based on rough logic, and proposes the optimal factorization of model, so one complex model could be factorized into several simple models, which are easy to be handled. this paper not only gives them some properties, but also analyze the time complexity of it. [Copyright &y& Elsevier]

Abstract: This paper firstly introduces rough logic, and proposes factorization of model based on rough logic, and proposes the optimal factorization of model, so one complex model could be factorized into several simple models, which are easy to be handled. this paper gives them somae properties. [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: At present, there is no specification on the disaster prevention of and relief from a semi-airtight underground ventilation equipment room. Based on the study of construction fire prevention at home and abroad, this paper carries on the analysis of personnel evacuation from an underground ventilation equipment room. It firstly conducts researches on the basic maxims, framework and procedure of disaster prevention, then sets the evaluation standards of safe evacuation and presents the major influential factors as well. Finally, this paper sets an evacuation model in the hope to reach the goal of safe disperse without any injury, i.e. RSET(x)

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: The paper presents a different approach on biomass combustion process modelling based on Bond Graph methodology. The main thermal-chemical processes used for biomass to energy conversion are oxidative. This study focused on oxidation process with heat generation using solid fuels. The important number of biomass categories and different conversion technologies influence the model input parameters in terms of temperatures, mass flows, heat exchange, requiring different models for combustion processes. The large range of biomass based products can be represented by carbon, hydrogen, oxygen, chlorine, sulphur, and nitrogen composition. In order to highlight the modelling method advantages, the research focused on wood biomass combustion. The product was represented by carbon, hydrogen, and oxygen composition given through their molar fraction. The paper presents the results on combustion process kinetics with respect to reactant and reactor input data, especially for the transitory regimes like ignition. The model provides information on time variation of the heat of reaction, reaction products concentration, and reactants concentration / accumulation, based on global mass and energy balance of the process. [Copyright &y& Elsevier]

Abstract: Using Cobb-Douglas production function to establish agricultural production function of Anhui province agriculture, this paper measures each input factor''s influence on total agricultural output, and calculates the contribution rate of agricultural technology progress; meanwhile, this paper analyzes the existing problems and solutions for the problems [Copyright &y& Elsevier]

Abstract: Distinguished from former literature which focuses on the static or balanced analysis, this paper established the timevarying parameters model based on state space model to find the dynamic relationship between China''s energy consumption and economic growth. After applying Chow test, unit root test and cointegration test, this paper estimated the parameters of state space model with Kalman Filter Algorithm, then found and analyzed their internal regularity. [Copyright &y& Elsevier]

Abstract: As CO2 is injected into a deep saline aquifer, three regions develop: A “drying” region next to the well in which CO2 injectate occupies 100% of the pore space, a brine region away from the injection well in which 100% of the pores are saturated with brine, and a two-phase region in which water and CO2 coexist. Several papers describe the speeds at which those two fronts progress outward using the Buckley-Leverett fractional flow (BLFF) theory. Next to a CO2 injection well and at early times, compositional flow theory must be implemented. It is also understood that far from the injection site, where only slight pressure elevation is felt, a single phase flow approach is sufficient because all the complexities of compositional flow could be neglected. However regulators may be wary of complex models and of the associated black box syndrome and rather may favor the simpler single-phase flow approach. This paper investigates using single-phase flow numerical models to describe compositional flow processes. Previous work already showed that results from the CMG-GEM and MODFLOW numerical codes are very similar away from the injection zone given some minor modifications in the input file of the single-phase flow code. We present a more thorough scoping analysis aiming at establishing the proposition that single-phase flow models (CMG-IMEX), given some simple treatment, can predict pressure increase as well as more complex compositional flow models (CMG-GEM). [Copyright &y& Elsevier]

Abstract: We incorporate CO2 dissolution due to convective mixing into a sharp-interface mathematical model for the post-injection migration of a plume of CO2 in a saline aquifer. The model captures CO2 migration due to groundwater flow and aquifer slope, as well as residual trapping and dissolution. We also account for the tongued shape of the plume at the end of the injection period. We solve the model numerically and identify three regimes in CO2 migration with dissolution, based on how quickly the brine beneath the plume saturates with dissolved CO2. When the brine saturates slowly relative to plume migration, dissolution is controlled by the dimensionless dissolution rate. When the brine saturates “instantaneously” relative to plume migration, dissolution is instead controlled by the solubility of CO2 in brine. We show that dissolution can lead to a several-fold increase in storage efficiency. In a companion paper, we study migration and pressure limitations on storage capacity [Szulczewski et al., GHGT-10, Paper 917 (2010)]. [Copyright &y& Elsevier]

Abstract: Evidence from experimental investigations, natural analogue studies and demonstration projects support the assertion that significant quantities of CO2 will not leak from a properly selected and managed CO2 storage complex. However, site operators must nevertheless justify the expectation of secure CO2 containment to regulators and other stakeholders. Secure containment will depend upon well seal stability inter alia. This paper presents fully-coupled geochemical models of well seal stability, focusing on cement degradation. The models have been developed with the ambition of reducing the simulated chemical system to the simplest possible configuration that is able to reproduce key features from experimental and field observations. Simplifying the models in this way makes them suitable for inclusion in larger scale system-level models of the storage system, where the use of highly-detailed chemical models can be impractical. Two sets of models were constructed in order to simulate: (1) a cement carbonation experiment (9 days in duration); and (2) field observations of cement degradation from the ‘SACROC’ site (30 years of reaction time). Although some model input parameters are uncertain, the experimental system was successfully simulated and the model was subsequently ‘up-scaled’ and applied to the SACROC core data. Over longer time-scales (102–103 years), the effects of parameter and thermodynamic data uncertainties on model output are more significant than at shorter time-scales. Although further work is required to bound the effects of these uncertainties, this paper illustrates the practicality of constructing simplified fully-coupled models to explore the significance of uncertainties by carrying out sensitivity calculations. [Copyright &y& Elsevier]

Abstract: We present a sharp-interface mathematical model of CO2 migration in saline aquifers, which accounts for gravity override, capillary trapping, natural groundwater flow, and the shape of the plume during the injection period. The model leads to a nonlinear advection–diffusion equation, where the diffusive term is due to buoyancy forces, not physical diffusion. For the case of interest in geological CO2 storage, in which the mobility ratio is very unfavorable, the mathematical model can be simplified to a hyperbolic equation. We present a complete analytical solution to the hyperbolic model. The main outcome is a closed-form expression that predicts the ultimate footprint on the CO2 plume, and the time scale required for complete trapping. The capillary trapping coefficient emerges as the key parameter in the assessment of CO2 storage in saline aquifers. The expressions derived here have immediate applicability to the risk assessment and capacity estimates of CO2 sequestration at the basin scale. In a companion paper [Szulczewski and Juanes, GHGT-9, Paper 463 (2008)] we apply the model to specific geologic basins. [Copyright &y& Elsevier]

Abstract: In this paper we show the results of the cost model developed in LIMA project (Seventh Framework Programme, CN: 248909). The LIMA project is entitled “Improve photovoltaic efficiency by applying novel effects at the limits of light to matter interaction”. The project started in January 2010 and during this year a cost model of the device developed in the project has been developed to assess the industrial viability of this innovative approach to increase the efficiency and reduce the cost of photovoltaic solar cells. During 2011 the cost model has been actualized and a new scenario has been defined. The LIMA project exploits cutting edge photonic technologies to enhance silicon solar cell efficiencies with new concepts in nanostructured materials. It proposes nanostructured surface layers designed to increase the light absorption in the solar cell while decreasing the surface and interface recombination loss. The integration on a back contact solar cell further reduces these interface losses and avoids shading. The project improves light-matter interaction by the use a surface plasmonic nanoparticle layer. This reduces reflection and efficiently couples incident radiation into the solar cell where it is trapped by internal reflection. Surface and interface recombination are minimized by using silicon quantum dot superlattices in a passivating matrix. [Copyright &y& Elsevier]

Abstract: This paper is revisiting the problem of recombination on locally processed area (contacts, local doping …), based on the concept of point recombination rate (pLPA). The newly introduced effective point recombination rate (peff) can be easily determined from the effective surface recombination velocity. It also allows predictions and comparisons in most of the practical cases. Further analysis allows the separation of the influence of pLPA from the one of the transport of the carrier in a transparent way. Due to its simplicity, transparency and accuracy, the model proposed here is believed to be more suitable to recent local processing technology than the existing analytical models. [Copyright &y& Elsevier]

Abstract: We present an investment analysis tool for natural gas infrastructure development. The model takes a system perspective and considers all existing infrastructure as well as the potential expansions. We formulate the investment problem as a deterministic mixed-integer linear program. We extend existing infrastructure analysis models within natural gas by adding pressure flow relationships and by modeling the gas quality in the transportation system. In this paper we present the motivation for the model functionality as well as the main components in the model. We also discuss a relevant investment case from the Norwegian Continental Shelf to exemplify typical model sizes as well as solution times. [Copyright &y& Elsevier]

Abstract: An overview of accidents and potential occupational accidents in the offshore wind industry is shown. There are indications that the number of accidents is relatively high. Based on a model for safe operations, status for as well as challenges for safety management in the offshore wind industry are presented. The paper concludes by presenting topics for further research. [Copyright &y& Elsevier]

Abstract: Offshore wind power is an emerging technology identified as a source of future growth by EDF Group, for which the number of wind farm projects will potentially increase in the future. Although there is greater potential for offshore wind generation, the investment to construct is more significant than onshore due with higher installation costs (essentially for foundations, electrical connections, towers and turbines). In addition to this, operation and maintenance needs more important access methods. In this context, a tool ECUME has been developed in recent years to support EDF Group in making its choices of investment, technologies and the development of operating and maintenance strategies for offshore wind turbines. The tool evaluates the total mean cost of operation of an offshore wind farm project, as early in the development process as its design phase, in order to help decision making on investment, technology selection, and life cycle logistics and maintenance strategies. This paper proposes some improvements to ECUME in order to supply more accurate output indicators as a simple mean cost which is not sufficient to make investment decisions about a farm, a design or a maintenance strategy. These decisions in the offshore wind context are exposed to greater uncertainty of failure occurrence and inaccessibility. Risk measurement indicators better fitted to the decision context can take into account the uncertainties in the evaluation of risks. This allows EDF to understand the confidence that can be accorded to the mean value assessed and the range of values between which the indicator is distributed; the risk that an investment is not profitable despite a positive mean Net Present Value, .. To provide these indicators, we introduce an event model (based on Monte-Carlo simulation) to model failure risk and HMM (Hidden Markov Model) to model the evolution of meteorological and marine parameters and evaluate inaccessibility risk. [Copyright &y& Elsevier]

Abstract: This paper discusses the modeling and control of Voltage Source Converter High Voltage Direct Current (VSC HVDC) systems in a multi-terminal configuration (MTDC). Both steady-state interactions, as well as transient stability modeling and control are addressed. Simulation results show that adequately modelling the DC voltage droop characteristics or a distributed voltage control in both the power flow algorithm and in the transient stability models allows to simulate the steady-state results of the dynamic simulation by means of power flow software algorithms. [Copyright &y& Elsevier]

Abstract: This paper presents the stability analysis based on impedance representation of a single phase inverter operating as voltage source, where the Nyquist criteria can be applied. The method can be used to study the stability of a micro-grid dominated by power electronics in isolated operation mode. First, a small signal input impedance model is described. The second methodology applies no energy storage at the AC and DC side of the inverter. For two methods a comparative evaluation with the measured impedance was realized. The obtained results show that the proposed method of no energy storage can be employed in the studies of stability for micro grid systems. [Copyright &y& Elsevier]

Abstract: The waterway counts as a main and costly part of a hydro power project. Excavating tunnels for waterways by rock-blasting is a rapid method compared to utilizing tunnel boring machines (TBM). However the variation in cross-section geometry and surface roughness that arises in unlined rock-blasted tunnels results in a considerable increase in head loss due to friction. Several empirical formulas are available to calculate the total friction loss of an unlined hydro-power tunnel. However, the existing methods of documenting the final geometry, such as manual measuring, leveling and photographing, are time-consuming and introduce uncertainty.Recent development of terrestrial laser scanners (TLS) has increased the efficiency and accuracy of surface measurements. Improved documentation of the geometry of these hydraulic structures enables higher accuracy in hand-calculations, as well as in physical and numerical modeling.This paper investigates the application of TLS on existing rock-blasted hydro power tunnels. The measuring procedures and results from a test performed by a Topcon GLS-1500 scanner are presented. The result shows that three dimensional representations of the tunnel geometry can be derived in an efficient way with high accuracy. Hence, this method yields as an efficient method to document the geometry and estimate the roughness of an existing unlined hydro power tunnel. Parameters such as accuracy, resolution, time consume and costs are investigated in the current study. [Copyright &y& Elsevier]

Abstract: Recently, various control models have been developed to optimize the performance of wave energy converters in order to enhance their long term economic value. Among others, the control of the all-electric Power Take Off (PTO) has been actively studied. This paper introduces the application of bio-inspired Ant Colony Optimization (ACO) metaheuristic as decision support for real-time wave energy extraction. It is found that the performance of the proposed algorithm is appealing as it is able to provide optimal parameter values to the control model within short interval. This provides fast-tuning capability to the PTO while sparing suffcient time for the WEC to respond to the continuously changing sea states. [Copyright &y& Elsevier]