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Sample records for charging station model

  1. Charging stations location model based on spatiotemporal electromobility use patterns

    Science.gov (United States)

    Pagany, Raphaela; Marquardt, Anna; Zink, Roland

    2016-04-01

    One of the major challenges for mainstream adoption of electric vehicles is the provision of infrastructure for charging the batteries of the vehicles. The charging stations must not only be located dense enough to allow users to complete their journeys, but the electric energy must also be provided from renewable sources in order to truly offer a transportation with less CO2 emissions. The examination of potential locations for the charging of electric vehicles can facilitate the adaption of electromobility and the integration of electronic vehicles in everyday life. A geographic information system (GIS) based model for optimal location of charging stations in a small and regional scale is presented. This considers parameters such as the forecast of electric vehicle use penetration, the relevant weight of diverse point of interests and the distance between parking area and destination for different vehicle users. In addition to the spatial scale the temporal modelling of the energy demand at the different charging locations has to be considerate. Depending on different user profiles (commuters, short haul drivers etc.) the frequency of charging vary during the day, the week and the year. In consequence, the spatiotemporal variability is a challenge for a reliable energy supply inside a decentralized renewable energy system. The presented model delivers on the one side the most adequate identified locations for charging stations and on the other side the interaction between energy supply and demand for electromobility under the consideration of temporal aspects. Using ESRI ArcGIS Desktop, first results for the case study region of Lower Bavaria are generated. The aim of the concept is to keep the model transferable to other regions and also open to integrate further and more detailed user profiles, derived from social studies about i.e. the daily behavior and the perception of electromobility in a next step.

  2. Research on Quantitative Models of Electric Vehicle Charging Stations Based on Principle of Energy Equivalence

    Directory of Open Access Journals (Sweden)

    Zhenpo Wang

    2013-01-01

    Full Text Available In order to adapt the matching and planning requirements of charging station in the electric vehicle (EV marketization application, with related layout theories of the gas stations, a location model of charging stations is established based on electricity consumption along the roads among cities. And a quantitative model of charging stations is presented based on the conversion of oil sales in a certain area. Both are combining the principle based on energy consuming equivalence substitution in process of replacing traditional vehicles with EVs. Defined data are adopted in the example analysis of two numerical case models and analyze the influence on charging station layout and quantity from the factors like the proportion of vehicle types and the EV energy consumption at the same time. The results show that the quantitative model of charging stations is reasonable and feasible. The number of EVs and the energy consumption of EVs bring more significant impact on the number of charging stations than that of vehicle type proportion, which provides a basis for decision making for charging stations construction layout in reality.

  3. A Hierarchical Optimization Model for a Network of Electric Vehicle Charging Stations

    Directory of Open Access Journals (Sweden)

    Cuiyu Kong

    2017-05-01

    Full Text Available Charging station location decisions are a critical element in mainstream adoption of electric vehicles (EVs. The consumer confidence in EVs can be boosted with the deployment of carefully-planned charging infrastructure that can fuel a fair number of trips. The charging station (CS location problem is complex and differs considerably from the classical facility location literature, as the decision parameters are additionally linked to a relatively longer charging period, battery parameters, and available grid resources. In this study, we propose a three-layered system model of fast charging stations (FCSs. In the first layer, we solve the flow capturing location problem to identify the locations of the charging stations. In the second layer, we use a queuing model and introduce a resource allocation framework to optimally provision the limited grid resources. In the third layer, we consider the battery charging dynamics and develop a station policy to maximize the profit by setting maximum charging levels. The model is evaluated on the Arizona state highway system and North Dakota state network with a gravity data model, and on the City of Raleigh, North Carolina, using real traffic data. The results show that the proposed hierarchical model improves the system performance, as well as the quality of service (QoS, provided to the customers. The proposed model can efficiently assist city planners for CS location selection and system design.

  4. An Analytical Planning Model to Estimate the Optimal Density of Charging Stations for Electric Vehicles.

    Directory of Open Access Journals (Sweden)

    Yongjun Ahn

    Full Text Available The charging infrastructure location problem is becoming more significant due to the extensive adoption of electric vehicles. Efficient charging station planning can solve deeply rooted problems, such as driving-range anxiety and the stagnation of new electric vehicle consumers. In the initial stage of introducing electric vehicles, the allocation of charging stations is difficult to determine due to the uncertainty of candidate sites and unidentified charging demands, which are determined by diverse variables. This paper introduces the Estimating the Required Density of EV Charging (ERDEC stations model, which is an analytical approach to estimating the optimal density of charging stations for certain urban areas, which are subsequently aggregated to city level planning. The optimal charging station's density is derived to minimize the total cost. A numerical study is conducted to obtain the correlations among the various parameters in the proposed model, such as regional parameters, technological parameters and coefficient factors. To investigate the effect of technological advances, the corresponding changes in the optimal density and total cost are also examined by various combinations of technological parameters. Daejeon city in South Korea is selected for the case study to examine the applicability of the model to real-world problems. With real taxi trajectory data, the optimal density map of charging stations is generated. These results can provide the optimal number of chargers for driving without driving-range anxiety. In the initial planning phase of installing charging infrastructure, the proposed model can be applied to a relatively extensive area to encourage the usage of electric vehicles, especially areas that lack information, such as exact candidate sites for charging stations and other data related with electric vehicles. The methods and results of this paper can serve as a planning guideline to facilitate the extensive

  5. An Analytical Planning Model to Estimate the Optimal Density of Charging Stations for Electric Vehicles.

    Science.gov (United States)

    Ahn, Yongjun; Yeo, Hwasoo

    2015-01-01

    The charging infrastructure location problem is becoming more significant due to the extensive adoption of electric vehicles. Efficient charging station planning can solve deeply rooted problems, such as driving-range anxiety and the stagnation of new electric vehicle consumers. In the initial stage of introducing electric vehicles, the allocation of charging stations is difficult to determine due to the uncertainty of candidate sites and unidentified charging demands, which are determined by diverse variables. This paper introduces the Estimating the Required Density of EV Charging (ERDEC) stations model, which is an analytical approach to estimating the optimal density of charging stations for certain urban areas, which are subsequently aggregated to city level planning. The optimal charging station's density is derived to minimize the total cost. A numerical study is conducted to obtain the correlations among the various parameters in the proposed model, such as regional parameters, technological parameters and coefficient factors. To investigate the effect of technological advances, the corresponding changes in the optimal density and total cost are also examined by various combinations of technological parameters. Daejeon city in South Korea is selected for the case study to examine the applicability of the model to real-world problems. With real taxi trajectory data, the optimal density map of charging stations is generated. These results can provide the optimal number of chargers for driving without driving-range anxiety. In the initial planning phase of installing charging infrastructure, the proposed model can be applied to a relatively extensive area to encourage the usage of electric vehicles, especially areas that lack information, such as exact candidate sites for charging stations and other data related with electric vehicles. The methods and results of this paper can serve as a planning guideline to facilitate the extensive adoption of electric

  6. An Analytical Planning Model to Estimate the Optimal Density of Charging Stations for Electric Vehicles

    Science.gov (United States)

    Ahn, Yongjun; Yeo, Hwasoo

    2015-01-01

    The charging infrastructure location problem is becoming more significant due to the extensive adoption of electric vehicles. Efficient charging station planning can solve deeply rooted problems, such as driving-range anxiety and the stagnation of new electric vehicle consumers. In the initial stage of introducing electric vehicles, the allocation of charging stations is difficult to determine due to the uncertainty of candidate sites and unidentified charging demands, which are determined by diverse variables. This paper introduces the Estimating the Required Density of EV Charging (ERDEC) stations model, which is an analytical approach to estimating the optimal density of charging stations for certain urban areas, which are subsequently aggregated to city level planning. The optimal charging station’s density is derived to minimize the total cost. A numerical study is conducted to obtain the correlations among the various parameters in the proposed model, such as regional parameters, technological parameters and coefficient factors. To investigate the effect of technological advances, the corresponding changes in the optimal density and total cost are also examined by various combinations of technological parameters. Daejeon city in South Korea is selected for the case study to examine the applicability of the model to real-world problems. With real taxi trajectory data, the optimal density map of charging stations is generated. These results can provide the optimal number of chargers for driving without driving-range anxiety. In the initial planning phase of installing charging infrastructure, the proposed model can be applied to a relatively extensive area to encourage the usage of electric vehicles, especially areas that lack information, such as exact candidate sites for charging stations and other data related with electric vehicles. The methods and results of this paper can serve as a planning guideline to facilitate the extensive adoption of electric

  7. Business Models for Solar Powered Charging Stations to Develop Infrastructure for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jessica Robinson

    2014-10-01

    Full Text Available Electric power must become less dependent on fossil fuels and transportation must become more electric to decrease carbon emissions and mitigate climate change. Increasing availability and accessibility of charging stations is predicted to increase purchases of electric vehicles. In order to address the current inadequate charging infrastructure for electric vehicles, major entities must adopt business models for solar powered charging stations (SPCS. These SPCS should be located in parking lots to produce electricity for the grid and provide an integrated infrastructure for charging electric vehicles. Due to the lack of information related to SPCS business models, this manuscript designs several models for major entities including industry, the federal and state government, utilities, universities, and public parking. A literature review of the available relevant business models and case studies of constructed charging stations was completed to support the proposals. In addition, a survey of a university’s students, staff, and faculty was conducted to provide consumer research on people’s opinion of SPCS construction and preference of business model aspects. Results showed that 69% of respondents would be more willing to invest in an electric vehicle if there was sufficient charging station infrastructure at the university. Among many recommendations, the business models suggest installing level 1 charging for the majority of entities, and to match entities’ current pricing structures for station use. The manuscript discusses the impacts of fossil fuel use, and the benefits of electric car and SPCS use, accommodates for the present gap in available literature on SPCS business models, and provides current consumer data for SPCS and the models proposed.

  8. Probabilistic modeling of nodal electric vehicle load due to fast charging stations

    DEFF Research Database (Denmark)

    Tang, Difei; Wang, Peng; Wu, Qiuwei

    2016-01-01

    In order to reduce greenhouse gas emission and fossil fuel dependence, Electric Vehicle (EV) has drawn increasing attention due to its zero emission and high efficiency. However, new problems such as range anxiety, long charging duration and high charging power may threaten the safe and efficient...... operation of both traffic and power systems. This paper proposes a probabilistic approach to model the nodal EV load at fast charging stations in integrated power and transport systems. Following the introduction of the spatial-temporal model of moving EV loads, we extended the model by taking fast charging......-temporal varying arrival and service rates. The time-varying nodal EV loads are obtained by the number of operating fast chargers at each node of the power system. System studies demonstrate that the combination of AC normal and DC charging may share the EV charging demand and alleviate the impact to power system...

  9. Autonomous Electrical Vehicles’ Charging Station

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    Józef Paska

    2016-09-01

    Full Text Available This paper presents a model of an autonomous electrical vehicles’ charging station. It consists of renewable energy sources: wind turbine system, photovoltaic cells, as well as an energy storage, load, and EV charging station. In order to optimise the operating conditions, power electronic converters were added to the system. The model was implemented in the Homer Energy programme. The first part of the paper presents the design assumptions and technological solutions. Further in the paper simulation results are discussed and analysed, and then problems observed in the simulation and possible solutions.

  10. Modeling of a Photovoltaic-Powered Electric Vehicle Charging Station with Vehicle-to-Grid Implementation

    Directory of Open Access Journals (Sweden)

    Azhar Ul-Haq

    2016-12-01

    Full Text Available This paper is aimed at modelling of a distinct smart charging station for electric vehicles (EVs that is suitable for DC quick EV charging while ensuring minimum stress on the power grid. Operation of the charging station is managed in such a way that it is either supplied by photovoltaic (PV power or the power grid, and the vehicle-to-grid (V2G is also implemented for improving the stability of the grid during peak load hours. The PV interfaced DC/DC converter and grid interfaced DC/AC bidirectional converter share a DC bus. A smooth transition of one operating mode to another demonstrates the effectiveness of the employed control strategy. Modelling and control of the different components are explained and are implemented in Simulink. Simulations illustrate the feasible behaviour of the charging station under all operating modes in terms of the four-way interaction among PV, EVs and the grid along with V2G operation. Additionally, a business model is discussed with comprehensive analysis of cost estimation for the deployment of charging facilities in a residential area. It has been recognized that EVs bring new opportunities in terms of providing regulation services and consumption flexibility by varying the recharging power at a certain time instant. The paper also discusses the potential financial incentives required to inspire EV owners for active participation in the demand response mechanism.

  11. Submerged AUV Charging Station

    Science.gov (United States)

    Jones, Jack A.; Chao, Yi; Curtin, Thomas

    2014-01-01

    Autonomous Underwater Vehicles (AUVs) are becoming increasingly important for military surveillance and mine detection. Most AUVs are battery powered and have limited lifetimes of a few days to a few weeks. This greatly limits the distance that AUVs can travel underwater. Using a series of submerged AUV charging stations, AUVs could travel a limited distance to the next charging station, recharge its batteries, and continue to the next charging station, thus traveling great distances in a relatively short time, similar to the Old West “Pony Express.” One solution is to use temperature differences at various depths in the ocean to produce electricity, which is then stored in a submerged battery. It is preferred to have the upper buoy submerged a reasonable distance below the surface, so as not to be seen from above and not to be inadvertently destroyed by storms or ocean going vessels. In a previous invention, a phase change material (PCM) is melted (expanded) at warm temperatures, for example, 15 °C, and frozen (contracted) at cooler temperatures, for example, 8 °C. Tubes containing the PCM, which could be paraffin such as pentadecane, would be inserted into a container filled with hydraulic oil. When the PCM is melted (expanded), it pushes the oil out into a container that is pressurized to about 3,000 psi (approx equals 20.7 MPa). When a valve is opened, the high-pressure oil passes through a hydraulic motor, which turns a generator and charges a battery. The low-pressure oil is finally reabsorbed into the PCM canister when the PCM tubes are frozen (contracted). Some of the electricity produced could be used to control an external bladder or a motor to the tether line, such that depth cycling is continued for a very long period of time. Alternatively, after the electricity is generated by the hydraulic motor, the exiting low-pressure oil from the hydraulic motor could be vented directly to an external bladder on the AUV, such that filling of the bladder

  12. Battery charging stations

    Energy Technology Data Exchange (ETDEWEB)

    Bergey, M.

    1997-12-01

    This paper discusses the concept of battery charging stations (BCSs), designed to service rural owners of battery power sources. Many such power sources now are transported to urban areas for recharging. A BCS provides the opportunity to locate these facilities closer to the user, is often powered by renewable sources, or hybrid systems, takes advantage of economies of scale, and has the potential to provide lower cost of service, better service, and better cost recovery than other rural electrification programs. Typical systems discussed can service 200 to 1200 people, and consist of stations powered by photovoltaics, wind/PV, wind/diesel, or diesel only. Examples of installed systems are presented, followed by cost figures, economic analysis, and typical system design and performance numbers.

  13. Feasibility Study of a Solar-Powered Electric Vehicle Charging Station Model

    Directory of Open Access Journals (Sweden)

    Bin Ye

    2015-11-01

    Full Text Available In China, the power sector is currently the largest carbon emitter and the transportation sector is the fastest-growing carbon emitter. This paper proposes a model of solar-powered charging stations for electric vehicles to mitigate problems encountered in China’s renewable energy utilization processes and to cope with the increasing power demand by electric vehicles for the near future. This study applies the proposed model to Shenzhen City to verify its technical and economic feasibility. Modeling results showed that the total net present value of a photovoltaic power charging station that meets the daily electricity demand of 4500 kWh is $3,579,236 and that the cost of energy of the combined energy system is $0.098/kWh. In addition, the photovoltaic powered electric vehicle model has pollutant reduction potentials of 99.8%, 99.7% and 100% for carbon dioxide, sulfur dioxide, and nitrogen oxides, respectively, compared with a traditional gasoline-fueled car. Sensitivity analysis results indicated that interest rate has a relatively strong influence on COE (Cost of Energy. An increase in the interest rate from 0% to 6% increases COE from $0.027/kWh to $0.097/kWh. This analysis also suggests that carbon pricing promotes renewable energy only when the price of carbon is above $20/t.

  14. VT Data - Electric Charging Stations

    Data.gov (United States)

    Vermont Center for Geographic Information — Locations of Electric Charging Stations provided by the NREL national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy....

  15. Modelling and Energy Management Optimisation of Battery Energy Storage System Based Photovoltaic Charging Station (PV-CS) for University Campus

    OpenAIRE

    Esfandyari, Ayda; Norton, Brian; Conlon, Michael

    2016-01-01

    As utilization of Photovoltaic Charging Stations (PV-CS) that generate clean electricity from the sun increase, Dublin Institute of Technology (DIT) adopts this application for accommodating the required charge of small campus Battery Electric Vehicles (BEVs). This paper presents the virtual simulation of the 10.5 kW Battery Energy Storage System (BESS) based PV-CS model. Transient System Simulation (TRNSYS) built-in climatic data and modular structure properties were adopted to replicate the...

  16. Modeling and Control of Flexible HEV Charging Station upgraded with Flywheel Energy Storage

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Shafiee, Qobad; Wu, Dan

    2014-01-01

    of power introduced by HEV charger, avoiding big initial stress in grid converter and also is able to limit the maximum extracted power. In addition, feed-forward compensation has been implemented to reduce the voltage dip within the station. Real time simulation results, that prove the validity......This paper deals with the design of a fast DC charging station (FCS) for hybrid electric vehicles (HEVs) that is connected at a remote location. Power rating of this new technology can go up to a hundred kW and it represents a main challenge for its broad acceptance in distribution systems....... In that sense, growing number of these stations, if operated in a nonflexible regime, will start to cause problems in future distribution systems such as overloads of local network’s corridors and reduction of its total equivalent spinning reserves. A power balancing strategy based on a local energy storage...

  17. Capacity Calculation of Shunt Active Power Filters for Electric Vehicle Charging Stations Based on Harmonic Parameter Estimation and Analytical Modeling

    Directory of Open Access Journals (Sweden)

    Niancheng Zhou

    2014-08-01

    Full Text Available The influence of electric vehicle charging stations on power grid harmonics is becoming increasingly significant as their presence continues to grow. This paper studies the operational principles of the charging current in the continuous and discontinuous modes for a three-phase uncontrolled rectification charger with a passive power factor correction link, which is affected by the charging power. A parameter estimation method is proposed for the equivalent circuit of the charger by using the measured characteristic AC (Alternating Current voltage and current data combined with the charging circuit constraints in the conduction process, and this method is verified using an experimental platform. The sensitivity of the current harmonics to the changes in the parameters is analyzed. An analytical harmonic model of the charging station is created by separating the chargers into groups by type. Then, the harmonic current amplification caused by the shunt active power filter is researched, and the analytical formula for the overload factor is derived to further correct the capacity of the shunt active power filter. Finally, this method is validated through a field test of a charging station.

  18. Alternative business models for establishing fast-charging stations - Part 2; Alternative forretningsmodeller for etablering av hurtigladestasjoner - Del 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-01

    This section of the report describes and evaluates potential business models for fast-charging stations. Business models are developed on the basis of market development for electric vehicles and electric vehicle usage patterns analyzed in Part 1 of the project. This report describes a series of models in both the early and maturity stage, where we have distinguished between different user segments and payment models. With the estimated trends in the car fleet and charger use, the prerequisites for profitable quick charging in the downtown area are good, while, due to high construction contribution, you must have a relatively high proportion of subscriptions and a high charge rate to obtain adequate finances in the corridor points.(auth)

  19. Dynamic Price Vector Formation Model-Based Automatic Demand Response Strategy for PV-Assisted EV Charging Stations

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Qifang; Wang, Fei; Hodge, Bri-Mathias; Zhang, Jianhua; Li, Zhigang; Shafie-Khah, Miadreza; Catalao, Joao P. S.

    2017-11-01

    A real-time price (RTP)-based automatic demand response (ADR) strategy for PV-assisted electric vehicle (EV) Charging Station (PVCS) without vehicle to grid is proposed. The charging process is modeled as a dynamic linear program instead of the normal day-ahead and real-time regulation strategy, to capture the advantages of both global and real-time optimization. Different from conventional price forecasting algorithms, a dynamic price vector formation model is proposed based on a clustering algorithm to form an RTP vector for a particular day. A dynamic feasible energy demand region (DFEDR) model considering grid voltage profiles is designed to calculate the lower and upper bounds. A deduction method is proposed to deal with the unknown information of future intervals, such as the actual stochastic arrival and departure times of EVs, which make the DFEDR model suitable for global optimization. Finally, both the comparative cases articulate the advantages of the developed methods and the validity in reducing electricity costs, mitigating peak charging demand, and improving PV self-consumption of the proposed strategy are verified through simulation scenarios.

  20. Modeling and Simulation of DC Microgrids for Electric Vehicle Charging Stations

    Directory of Open Access Journals (Sweden)

    Fabrice Locment

    2015-05-01

    Full Text Available This paper focuses on the evaluation of theoretical and numerical aspects related to an original DC microgrid power architecture for efficient charging of plug-in electric vehicles (PEVs. The proposed DC microgrid is based on photovoltaic array (PVA generation, electrochemical storage, and grid connection; it is assumed that PEVs have a direct access to their DC charger input. As opposed to conventional power architecture designs, the PVA is coupled directly on the DC link without a static converter, which implies no DC voltage stabilization, increasing energy efficiency, and reducing control complexity. Based on a real-time rule-based algorithm, the proposed power management allows self-consumption according to PVA power production and storage constraints, and the public grid is seen only as back-up. The first phase of modeling aims to evaluate the main energy flows within the proposed DC microgrid architecture and to identify the control structure and the power management strategies. For this, an original model is obtained by applying the Energetic Macroscopic Representation formalism, which allows deducing the control design using Maximum Control Structure. The second phase of simulation is based on the numerical characterization of the DC microgrid components and the energy management strategies, which consider the power source requirements, charging times of different PEVs, electrochemical storage ageing, and grid power limitations for injection mode. The simulation results show the validity of the model and the feasibility of the proposed DC microgrid power architecture which presents good performance in terms of total efficiency and simplified control.

  1. Optimal Charging Schedule Planning and Economic Analysis for Electric Bus Charging Stations

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    Rong-Ceng Leou

    2017-04-01

    Full Text Available The battery capacity of electric buses (EB used for public transportation is greater than that of electric cars, and the charging power is also several times greater than that used in electric cars; this can result in high energy consumption and negatively impact power distribution networks. This paper proposes a framework to determine the optimal contracted power capacity and charging schedule of an EB charging station in such a way that energy costs can be reduced. A mathematical model of controlled charging, which includes the capacity and energy charges of the station, was developed to minimize costs. The constraints of the model include the charging characteristics of an EB and the operational guidelines of the bus company. A practical EB charging station was used to verify the proposed model. The financial viability of this EB charging station is also studied in this paper. The economic analysis model for this charging station considers investment and operational costs, and the operational revenue. Sensitivity analyses with respect to some key parameters are also performed in this paper. Based on actual operational routes and EB charging schemes, test results indicate that the EB charging station investment is feasible, and the planning model proposed can be used to determine optimal station power capacity and minimize energy costs.

  2. Electric Vehicle Charging Stations as a Climate Change Mitigation Strategy

    Science.gov (United States)

    Cave, Bridget; DeYoung, Russell J.

    2014-01-01

    In order to facilitate the use of electric vehicles at NASA Langley Research Center (LaRC), charging stations should be made available to LaRC employees. The implementation of charging stations would decrease the need for gasoline thus decreasing CO2 emissions improving local air quality and providing a cost savings for LaRC employees. A charging station pilot program is described that would install stations as the need increased and also presents a business model that pays for the electricity used and installation at no cost to the government.

  3. Study of a New Quick-Charging Strategy for Electric Vehicles in Highway Charging Stations

    Directory of Open Access Journals (Sweden)

    Lixing Chen

    2016-09-01

    Full Text Available To solve the problem, because of which conventional quick-charging strategies (CQCS cannot meet the requirements of quick-charging for multiple types of electric vehicles (EV on highways where vehicle inflow is excessive, this paper proposed a new quick-charging strategy (NQCS for EVs: on the premise of not affecting those EVs being charged, the remaining power of the quick-charging pile with multiple power output interfaces is used to provide a synchronous charging service for EVs waiting in the queue. To verify the effectiveness of this strategy, a power distribution model of charging pile and a queuing model of charging station (CS were constructed. In addition, based on an actual highway service area where vehicle inflow is excessive during the simulation period (0:00–24:00, charging situations of CQCS and NQCS were respectively simulated in a charging station (CS, with different number of chargers, by basic queuing algorithm and an improved queuing algorithm. The simulation results showed that when the relative EV inflow is excessive, compared to CQCS, NQCS not only can reduce user waiting time, charging time, and stay time, but also can improve the utilisation rate of charging infrastructure and service capacity of CS and reduce the queue length of CS. At the same time, NQCS can reduce the impact on the power grid. In addition, in NQCS, the on-demand power distribution method is more efficient than the average power distribution method. Therefore, NQCS is more suitable for quick-charging for multiple types of EVs on highways where vehicle inflow is excessive.

  4. Impact of Electric Vehicle Charging Station Load on Distribution Network

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    Sanchari Deb

    2018-01-01

    Full Text Available Recent concerns about environmental pollution and escalating energy consumption accompanied by the advancements in battery technology have initiated the electrification of the transportation sector. With the universal resurgence of Electric Vehicles (EVs the adverse impact of the EV charging loads on the operating parameters of the power system has been noticed. The detrimental impact of EV charging station loads on the electricity distribution network cannot be neglected. The high charging loads of the fast charging stations results in increased peak load demand, reduced reserve margins, voltage instability, and reliability problems. Further, the penalty paid by the utility for the degrading performance of the power system cannot be neglected. This work aims to investigate the impact of the EV charging station loads on the voltage stability, power losses, reliability indices, as well as economic losses of the distribution network. The entire analysis is performed on the IEEE 33 bus test system representing a standard radial distribution network for six different cases of EV charging station placement. It is observed that the system can withstand placement of fast charging stations at the strong buses up to a certain level, but the placement of fast charging stations at the weak buses of the system hampers the smooth operation of the power system. Further, a strategy for the placement of the EV charging stations on the distribution network is proposed based on a novel Voltage stability, Reliability, and Power loss (VRP index. The results obtained indicate the efficacy of the VRP index.

  5. An Electric Power Consumption Analysis System for the Installation of Electric Vehicle Charging Stations

    Directory of Open Access Journals (Sweden)

    Seongpil Cheon

    2017-10-01

    Full Text Available With the rising demand for electric vehicles, the number of electric vehicle charging stations is increasing. Therefore, real-time monitoring of how the power consumption by charging stations affects the load on the peripheral power grid is important. However, related organizations generally do not provide actual power consumption data in real time, and only limited information, such as the charging time, is provided. Therefore, it is difficult to calculate and predict the power load in real time. In this paper, we propose a new model for estimating the electric power consumption from the supplied information, i.e., the charging time and the number of charging involved. The experimental results show that by displaying this information on a map, it is possible to visually monitor the electric power consumption of the charging stations with an accuracy rate of about 86%. Finally, the proposed system can be used to relocate and select the location of vehicle charging stations.

  6. Flywheel-Based Fast Charging Station - FFCS for Electric Vehicles and Public Transportation

    Science.gov (United States)

    Gabbar, Hossam A.; Othman, Ahmed M.

    2017-08-01

    This paper demonstrates novel Flywheel-based Fast Charging Station (FFCS) for high performance and profitable charging infrastructures for public electric buses. The design criteria will be provided for fast charging stations. The station would support the private and open charging framework. Flywheel Energy storage system is utilized to offer advanced energy storage for charging stations to achieve clean public transportation, including electric buses with reducing GHG, including CO2 emission reduction. The integrated modelling and management system in the station is performed by a decision-based control platform that coordinates the power streams between the quick chargers, the flywheel storage framework, photovoltaic cells and the network association. There is a tidy exchange up between the capacity rate of flywheel framework and the power rating of the network association.”

  7. LAYOUT AND DESIGN OF ELECTROMOBILE CHARGING STATIONS AS URBAN ELEMENTS

    Directory of Open Access Journals (Sweden)

    Tomáš Chovan

    2015-12-01

    Full Text Available The contribution is dedicated to the processing of the problems of the insufficient charging for the electric vehicles within the concrete urbanistic centre. It brings a different perspective on the mobility, which is shown in the form of electric energy as the alternative for the needs of urbanization of the cities. It analyses electromobility, new technologies in the field of electric vehicles and the charging stations as the elements of the urbanism. In terms of the solution, the contribution is focused on the Košice city and the location of the public charging stations. Košice do not have sufficient amount of the public charging stations and until the 2014 there was only one public charging station. The contribution is focused on the designing of the parking places with the charging station placed on the appropriate parking places. The resulting design is created in the CAD system, it brings the view of the layout of the charging station at the shopping centre in the open space and in the parking house.

  8. The economic feasibility of renewable powered fast charging stations

    Energy Technology Data Exchange (ETDEWEB)

    Benger, Ralf; Heyne, Raoul; Wenzl, Heinz; Beck, Hans-Peter

    2011-07-01

    Electric vehicles will make an important contribution for a sustainable energy supply in the public transport sector. Although it is not sure at the moment which role the different vehicle concepts and charging options will play, it is possible to act on following assumptions: There will be purely electrically operated vehicles (EV), which will need a charging infrastructure in the public domain. Even if the number of these vehicles in comparison with hybrid electric vehicles (HEV) or range extended electric vehicles (REV) will be low, in the long run an amount of some million vehicles can be reached (1 0 % of the vehicles in Germany corresponds to round about 4 million vehicles). Charging stations in parking areas, shopping malls, at home or at work do not require high charging power because the time available for charging is relative long. In contrast charging stations beside these in normal parking areas should have the ability to charge the car batteries in a very short time, e.g. 80% of the energy content in 15 minutes or less. Therefore every charging process requires 100-200 kW electric power. Such charging stations are necessary both in rural and in urban regions.

  9. Real-Time Forecasting of EV Charging Station Scheduling for Smart Energy Systems

    Directory of Open Access Journals (Sweden)

    Bharatiraja Chokkalingam

    2017-03-01

    Full Text Available The enormous growth in the penetration of electric vehicles (EVs, has laid the path to advancements in the charging infrastructure. Connectivity between charging stations is an essential prerequisite for future EV adoption to alleviate user’s “range anxiety”. The existing charging stations fail to adopt power provision, allocation and scheduling management. To improve the existing charging infrastructure, data based on real-time information and availability of reserves at charging stations could be uploaded to the users to help them locate the nearest charging station for an EV. This research article focuses on an a interactive user application developed through SQL and PHP platform to allocate the charging slots based on estimated battery parameters, which uses data communication with charging stations to receive the slot availability information. The proposed server-based real-time forecast charging infrastructure avoids waiting times and its scheduling management efficiently prevents the EV from halting on the road due to battery drain out. The proposed model is implemented using a low-cost microcontroller and the system etiquette tested.

  10. Solar-Assisted Electric Vehicle Charging Station Interim Report

    Energy Technology Data Exchange (ETDEWEB)

    Lapsa, Melissa Voss [ORNL; Durfee, Norman [ORNL; Maxey, L Curt [ORNL; Overbey, Randall M [ORNL

    2011-09-01

    Oak Ridge National Laboratory (ORNL) has been awarded $6.8 million in the Department of Energy (DOE) American Recovery and Reinvestment Act (ARRA) funds as part of an overall $114.8 million ECOtality grant with matching funds from regional partners to install 125 solar-assisted Electric Vehicle (EV) charging stations across Knoxville, Nashville, Chattanooga, and Memphis. Significant progress has been made toward completing the scope with the installation of 25 solar-assisted charging stations at ORNL; six stations at Electric Power Research Institute (EPRI); and 27 stations at Nissan's Smyrna and Franklin sites, with three more stations under construction at Nissan's new lithium-ion battery plant. Additionally, the procurement process for contracting the installation of 34 stations at Knoxville, the University of Tennessee Knoxville (UTK), and Nashville sites is underway with completion of installation scheduled for early 2012. Progress is also being made on finalizing sites and beginning installations of 30 stations in Nashville, Chattanooga, and Memphis by EPRI and Tennessee Valley Authority (TVA). The solar-assisted EV charging station project has made great strides in fiscal year 2011. A total of 58 solar-assisted EV parking spaces have been commissioned in East and Middle Tennessee, and progress on installing the remaining 67 spaces is well underway. The contract for the 34 stations planned for Knoxville, UTK, and Nashville should be underway in October with completion scheduled for the end of March 2012; the remaining three Nissan stations are under construction and scheduled to be complete in November; and the EPRI/TVA stations for Chattanooga, Vanderbilt, and Memphis are underway and should be complete by the end of March 2012. As additional Nissan LEAFs are being delivered, usage of the charging stations has increased substantially. The project is on course to complete all 125 solar-assisted EV charging stations in time to collect meaningful data

  11. Electric vehicle charging station implementation plans for the Upstate New York I-90 corridor : final report.

    Science.gov (United States)

    2016-08-01

    Public charging stations allow electric vehicle (EV) owners to have the ability and confidence to drive throughout New York State; for travel within and between metropolitan areas. Incorporating EV charging station planning into broader local and reg...

  12. A review of technical options for solar charging stations in Asia and Africa

    Directory of Open Access Journals (Sweden)

    R. H. Almeida

    2015-09-01

    Full Text Available Charging stations are an attractive solution to provide access to electricity to low income populations with low energy consumption in remote and off-grid areas. This paper reviews the state of the art of charging stations, with special focus on the technical options. Forty-five different actors in this field were analysed, based on academic publications, reports, online search and surveys. Results show that most stations are run in Sub Saharan Africa and South Asia, are powered by solar energy and although there are many different energy services targeted, the most popular services are charging batteries, mobile phones and lamps. The first charging station was installed in 1992 but most activities happen after 2005. This recent growth has been enabled by the falling cost of photovoltaic modules, learning effect, economies of scale, financial innovation, private sector involvement and worldwide dissemination of mobile phones. While in the first system the only purpose was to charge solar photovoltaic lanterns, the first multi-purpose station appeared in 2008. As expected, the technical challenges are mostly related to the use of batteries not only because they represent the component with shortest lifetime but also because if the battery is not for individual use, social questions arise due to poor definition of rights and duties of the customers. Furthermore, the development of a sustainable business model is also a challenge since this requires technical skills and system monitoring that are not usually available locally. Finally, it is also suggested that the minimum technical quality standards for charging stations should be defined and implemented.

  13. Modeling and Analyzing Electric Vehicle Charging

    DEFF Research Database (Denmark)

    Andersen, Ove; Krogh, Benjamin Bjerre; Thomsen, Christian

    2016-01-01

    The combined battery capacity in electric vehicles (EVs) is considered an integral part of balancing a smart power grid in the future. In addition, EVs can reduce the usage of fossil fuels in the transport sector because EVs can be charged using electricity from renewable energy sources...... on all aspects of charging EVs, including integration with the electricity prices from a spot market. The proposed data warehouse is fully implemented and currently contains 2.5 years of charging data from 176 EVs. We describe the date warehouse model and the implementation including complex operations...... such as spatially identifying charging station usage patterns. Further, we give examples of novel analyses, e.g., how the free battery capacity in the fleet of EVs changes over the day and how users can save money by charging the EVs when the electricity price is the lowest....

  14. A Novel Assessment Method of Charging Station Planning Based on Fuzzy Matter Element Theory

    Directory of Open Access Journals (Sweden)

    Zhao Junyi

    2017-01-01

    Full Text Available Scientific and rational planning of urban electric vehicles (EVs charging station is an important prerequisite for large scale EVs interact with smart grid friendly. This article realizes the planning assessment of EV charging station based on fuzzy matter element theory. The features of urban EV charging station are analyzed, and the evaluation index system of alternative charging station is established. The paper applies fuzzy matter element analysis method to obtain the optimal fuzzy matter element sequence with alternative points, and as a reference sequence. The weights of alternative points corresponding evaluation index are obtained by entropy method. Then, the paper applies the gray correlation analysis to calculate the gray relational weighing degree of fuzzy matter element sequence of alternative points, and determine the EV charging station plan based on the size of gray relational weighing degree. Finally, the simulation results show that the proposed method is effective and feasible for EV charging station planning.

  15. Level 1 Electric Vehicle Charging Stations at the Workplace

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Margaret [Energetics Incorporated, Columbia, MD (United States)

    2016-07-29

    Level 1 charging (110-120 V) can be a good fit for many workplace charging programs. This document highlights the experiences of a selection of Workplace Charging Challenge partners that use Level 1 charging.

  16. Design and development of electric vehicle charging station equipped with RFID

    Science.gov (United States)

    Panatarani, C.; Murtaddo, D.; Maulana, D. W.; Irawan, S.; Joni, I. M.

    2016-02-01

    This paper reports the development of electric charging station from distributed renewable for electric vehicle (EV). This designed refer to the input voltage standard of IEC 61851, plugs features of IEC 62196 and standard communication of ISO 15118. The developed electric charging station used microcontroller ATMEGA8535 and RFID as controller and identifier of the EV users, respectively. The charging station successfully developed as desired features for electric vehicle from renewable energy resources grid with solar panel, wind power and batteries storage.

  17. Electric Vehicle Charging Modeling

    OpenAIRE

    Grahn, Pia

    2014-01-01

    With an electrified passenger transportation fleet, carbon dioxide emissions could be reduced significantly depending on the electric power production mix. Increased electric power consumption due to electric vehicle charging demands of electric vehicle fleets may be met by increased amount of renewable power production in the electrical systems. With electric vehicle fleets in the transportation system there is a need for establishing an electric vehicle charging infrastructure that distribu...

  18. In situ measurement of electrostatic charge and charge distribution on flyash particles in power station exhaust stream

    Energy Technology Data Exchange (ETDEWEB)

    Guang, D.

    1992-01-01

    The electrostatic charges and charge distributions on individual flyash particles were experimentally measured in situ at four power stations in New South Wales and in the laboratory with an Electrostatic Charge Classifier. The global charge of these flyashes was also measured. The electrostatic charge on flyash particles of four power stations was found to be globally native. The median charge on the flyash particles varies linearly with particle diameter for all four flyashes. The electrostatic charge on the Tallawarra flyash particles was found to increase after passage through the air heater having huge metal surface areas, suggesting that triboelectrification was the primary charging mechanism for flyash particles. Distinctly different characteristics of the electrostatic charge, particle size and particle shape were found between the Eraring and the Tallawarra flyashes. The spherical Eraring ash has the highest proportion of lines and positively charged particles, but the lowest global charge level among the four flyashes. In contrast, the Tallawarra flyash has just the opposite. It is the distinct characteristics of the flyashes from Eraring and Tallawarra power stations that are responsible for the significant differences in their baghouse performance. The napping feature on the surface of the filter bags used in the Eraring and Tallawarra power stations provides an upstream surface of low fibre density above the fabric bulk. This feature presents and advantage to highly charged particles, like the Tallawarra flyash particles. Highly charged particles tend to deposit on such an upstream surface resulting in a porous dust cake with much less contact areas with the fabric medium than would otherwise be formed. This cake is easy to remove and provides less resistance to the gas flow. After singeing the naps on the filter bag surface at the Eraring power station, the problems of high pressure drop and retention of dust cake on the bas surface have been resolved.

  19. Probabilistic Harmonic Calculation in Distribution Networks with Electric Vehicle Charging Stations

    Directory of Open Access Journals (Sweden)

    Jianxue Wang

    2014-01-01

    Full Text Available Integrating EV charging station into power grid will bring impacts on power system, among which the most significant one is the harmonic pollution on distribution networks. Due to the uncertainty of the EV charging process, the harmonic currents brought by EV charging stations have a random nature. This paper proposed a mathematical simulation method for studying the working status of charging stations, which considers influencing factors including random leaving factor, electricity price, and waiting time. Based on the proposed simulation method, the probability distribution of the harmonic currents of EV charging stations is obtained and used in the calculation of the probability harmonic power flow. Then the impacts of EVs and EV charging stations on distribution networks can be analyzed. In the case study, the proposed simulation and analysis method is implemented on the IEEE-34 distribution network. The influences of EV arrival rates, the penetration rate, and the accessing location of EV charging station are also investigated. Results show that this research has good potential in guiding the planning and construction of charging station.

  20. Multiple Charging Station Location-Routing Problem with Time Window of Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Wang Li-ying

    2015-11-01

    Full Text Available This paper presents the electric vehicle (EV multiple charging station location-routing problem with time window to optimize the routing plan of capacitated EVs and the strategy of charging stations. In particular, the strategy of charging stations includes both infrastructure-type selection and station location decisions. The problem accounts for two critical constraints in logistic practice: the vehicle loading capacity and the customer time windows. A hybrid heuristic that incorporates an adaptive variable neighborhood search (AVNS with the tabu search algorithm for intensification was developed to address the problem. The specialized neighborhood structures and the selection methods of charging station used in the shaking step of AVNS were proposed. In contrast to the commercial solver CPLEX, experimental results on small-scale test instances demonstrate that the algorithm can find nearly optimal solutions on small-scale instances. The results on large-scale instances also show the effectiveness of the algorithm.

  1. A Bi-Level Optimization Approach to Charging Load Regulation of Electric Vehicle Fast Charging Stations Based on a Battery Energy Storage System

    Directory of Open Access Journals (Sweden)

    Yan Bao

    2018-01-01

    Full Text Available Fast charging stations enable the high-powered rapid recharging of electric vehicles. However, these stations also face challenges due to power fluctuations, high peak loads, and low load factors, affecting the reliable and economic operation of charging stations and distribution networks. This paper introduces a battery energy storage system (BESS for charging load control, which is a more user-friendly approach and is more robust to perturbations. With the goals of peak-shaving, total electricity cost reduction, and minimization of variation in the state-of-charge (SOC range, a BESS-based bi-level optimization strategy for the charging load regulation of fast charging stations is proposed in this paper. At the first level, a day-ahead optimization strategy generates the optimal planned load curve and the deviation band to be used as a reference for ensuring multiple control objectives through linear programming, and even for avoiding control failure caused by insufficient BESS energy. Based on this day-ahead optimal plan, at a second level, real-time rolling optimization converts the control process to a multistage decision-making problem. The predictive control-based real-time rolling optimization strategy in the proposed model was used to achieve the above control objectives and maintain battery life. Finally, through a horizontal comparison of two control approaches in each case study, and a longitudinal comparison of the control robustness against different degrees of load disturbances in three cases, the results indicated that the proposed control strategy was able to significantly improve the charging load characteristics, even with large disturbances. Meanwhile, the proposed approach ensures the least amount of variation in the range of battery SOC and reduces the total electricity cost, which will be of a considerable benefit to station operators.

  2. Combined Solar Charging Stations and Energy Storage Units Allocation for Electric Vehicles by Considering Uncertainties

    DEFF Research Database (Denmark)

    Yousefi Khanghah, Babak; Anvari-Moghaddam, Amjad; Guerrero, Josep M.

    2017-01-01

    Electric vehicles (EVs) are becoming a key feature of smart grids. EVs will be embedded in the smart grids as a mobile load-storage with probabilistic behavior. In order to manage EVs as flexible loads, charging stations (CSs) have essential roles. In this paper, a new method for optimal sitting...... and sizing of solar CSs using energy storage (ES) options is presented. Also, behavior of EVs in the presence of other loads, electricity price and solar power generation uncertainties are considered. The proposed optimization model maximizes the distribution company (DisCo) benefit by appropriate use of CSs...... are considered based on time-of-use (TOU) demand response programs (DRPs). In order to solve the optimization problem considering uncertainty of load growth, electricity price, initial state of charge of batteries and solar power generation, genetic algorithm method using Monte-Carlo simulation is used...

  3. SPHERES/Universal ISS Battery Charging Station Project

    Data.gov (United States)

    National Aeronautics and Space Administration — With the retiring of the shuttle fleet, up-mass and down-mass to ISS are at a premium. The space station itself has a limited lifecycle as well, thus long-term...

  4. Integration Assessment of Visiting Vehicle Induced Electrical Charging of the International Space Station Structure

    Science.gov (United States)

    Kramer, Leonard; Kerslake, Thomas W.; Galofaro, Joel T.

    2010-01-01

    The International Space Station (ISS) undergoes electrical charging in low Earth orbit (LEO) due to positively biased, exposed conductors on solar arrays that collect electrical charges from the space plasma. Exposed solar array conductors predominately collect negatively charged electrons and thus drive the metal ISS structure electrical ground to a negative floating potential (FP) relative to plasma. This FP is variable in location and time as a result of local ionospheric conditions. ISS motion through Earth s magnetic field creates an addition inductive voltage up to 20 positive and negative volts across ISS structure depending on its attitude and location in orbit. ISS Visiting Vehicles (VVs), such as the planned Orion crew exploration vehicle, contribute to the ISS plasma charging processes. Upon physical contact with ISS, the current collection properties of VVs combine with ISS. This is an ISS integration concern as FP must be controlled to minimize arcing of ISS surfaces and ensure proper management of extra vehicular activity crewman shock hazards. This report is an assessment of ISS induced charging from docked Orion vehicles employing negatively grounded, 130 volt class, UltraFlex (ATK Space Systems) solar arrays. To assess plasma electron current collection characteristics, Orion solar cell test coupons were constructed and subjected to plasma chamber current collection measurements. During these tests, coupon solar cells were biased between 0 and 120 V while immersed in a simulated LEO plasma. Tests were performed using several different simulated LEO plasma densities and temperatures. These data and associated theoretical scaling of plasma properties, were combined in a numerical model which was integrated into the Boeing Plasma Interaction Model. It was found that the solar array design for Orion will not affect the ISS FP by more than about 2 V during worst case charging conditions. This assessment also motivated a trade study to determine

  5. Flywheel-Based Distributed Bus Signalling Strategy for the Public Fast Charging Station

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Sucic, Stepjan; Vasquez, Juan Carlos

    2014-01-01

    Fast charging stations (FCS) are able to recharge plug-in hybrid electric vehicles (pHEVs) in less than half an hour, thus representing an appealing concept to vehicle owners since the off-road time is similar as for refuelling at conventional public gas stations. However, since these FCS plugs...

  6. Cost-Benefit Analysis of a Novel DC Fast-Charging Station with a Local Battery Storage for EVs

    DEFF Research Database (Denmark)

    Gjelaj, Marjan; Træholt, Chresten; Hashemi Toghroljerdi, Seyedmostafa

    2017-01-01

    The increasing penetration of Electric Vehicles (EVs) and their charging systems is representing new highpower consumption loads for the distribution system operators (DSOs). To solve the problem of the EV range in terms of driving kilometers, the car manufacturers have invested resources on new EV...... models by increasing the size of the batteries. To satisfy EV load demand of the new EV models in urban areas the public DC Fast-Charging Station (DCFCS) is indispensable to recharge EVs rapidly. The introduction of the Battery Energy Storage within the DCFCSs is considered in this paper an alternative...... solution to reduce the operational costs of the charging stations as well as the ability to mitigate negative impacts during the congestion on the power grids. An accurate description of the DCFCS and its design system, which is able to decouple the peak load demand caused by EVs on the main grid...

  7. Intention-Aware Routing to Minimise Delays at Electric Vehicle Charging Stations

    NARCIS (Netherlands)

    De Weerdt, M.M.; Gerding, E.H.; Stein, S.; Robu, V.; Jennings, N.R.

    2013-01-01

    En-route charging stations allow electric vehicles to greatly extend their range. However, as a full charge takes a considerable amount of time, there may be significant waiting times at peak hours. To address this problem, we propose a novel navigation system, which communicates its intentions

  8. Heuristic Storage System Sizing for Optimal Operation of Electric Vehicles Powered by Photovoltaic Charging Station

    OpenAIRE

    Blasius, Erik; Federau, Erik; Janik, Przemyslaw; Leonowicz, Zbigniew

    2016-01-01

    This paper discusses the utilisation of PV systems for electric vehicles charging for transportation requirements of smart cities. The gap between PV power output and vehicles charging demand is highly variable. Therefore, there is a need for additional support from a public distribution grid or a storage device in order to handle the residual power. Long term measurement data retrieved from a charging station for 15 vehicles equipped with a PV system were used in the research. Low and high i...

  9. Reactive Power Support of Electrical Vehicle Charging Station Upgraded with Flywheel Energy Storage System

    DEFF Research Database (Denmark)

    SUN, BO; Dragicevic, Tomislav; Savaghebi, Mehdi

    2015-01-01

    Electrical vehicles (EVs) are presenting increasingly potential to replace the conventional fossil fuel based vehicles due to environmental friendly characteristic. Accordingly, Charging Stations (CS), as an intermediate between grid and large numbers of EVs, are supposed to have more critical...... influence on future smart transportation network. This paper explores an off-board charging station upgraded with flywheel energy storage system that could provide a reactive power support to the grid utility. A supervisory control scheme based on distributed bus signaling is proposed to coordinate...... the operation of each component in the system. As a result, the charging station could supply the reactive power support to the utility grid without compromising the charging algorithm and preserve the battery’s lifetime. Finally, the real-time simulation results based on dSPACE1006 verifies the proposed...

  10. Optimal planning of electric vehicle charging station at the distribution system using hybrid optimization algorithm

    DEFF Research Database (Denmark)

    Awasthi, Abhishek; Venkitusamy, Karthikeyan; Padmanaban, Sanjeevikumar

    2017-01-01

    India's ever increasing population has made it necessary to develop alternative modes of transportation with electric vehicles being the most preferred option. The major obstacle is the deteriorating impact on the utility distribution system brought about by improper setup of these charging...... stations. This paper deals with the optimal planning (siting and sizing) of charging station infrastructure in the city of Allahabad, India. This city is one of the upcoming smart cities, where electric vehicle transportation pilot project is going on under Government of India initiative. In this context...

  11. Load forecast method of electric vehicle charging station using SVR based on GA-PSO

    Science.gov (United States)

    Lu, Kuan; Sun, Wenxue; Ma, Changhui; Yang, Shenquan; Zhu, Zijian; Zhao, Pengfei; Zhao, Xin; Xu, Nan

    2017-06-01

    This paper presents a Support Vector Regression (SVR) method for electric vehicle (EV) charging station load forecast based on genetic algorithm (GA) and particle swarm optimization (PSO). Fuzzy C-Means (FCM) clustering is used to establish similar day samples. GA is used for global parameter searching and PSO is used for a more accurately local searching. Load forecast is then regressed using SVR. The practical load data of an EV charging station were taken to illustrate the proposed method. The result indicates an obvious improvement in the forecasting accuracy compared with SVRs based on PSO and GA exclusively.

  12. Semigraphical model of railway stations operation

    OpenAIRE

    Верлан, Анатолий Иванович

    2014-01-01

    Semigraphical model of railway stations operation for technical and operational evaluation of their technology is presented in the paper. The paper is aimed at improving the model structure to simplify the mechanical engineer's interaction with a computer at the stage of a formal description of the model. In the simulation, railway station is considered as a complex system, in which maintenance of facilities by technical means and executors is carried out by performing manufacturing operation...

  13. Connection Facility Layout Model of Subway Stations

    Directory of Open Access Journals (Sweden)

    Liya Yao

    2015-01-01

    Full Text Available As the key node of public transportation system, subway station has many functions such as attracting and distributing passengers and guiding the transfer from various traffic modes to subway. However, the poor facility scale and layout around subway stations in practice usually cause the inconvenience of transfer and low transfer efficiency, which causes the declination of travel efficiency and even loose of subway passengers. Taking subway stations as the study objects, this paper has emphasis on the connection characters between various traffic modes and subway stations. Considering the attraction region, the total transfer time, transfer distance, and connection cost were selected to form the efficiency index of connection layout of subway stations. Data envelopment analysis (DEA model is applied in the quantization of traffic resource consumption and output. At last, connection facility layout model of subway stations was established with the aim of improving the transfer efficiency. Meaningful results were obtained from the connection layout model of subway stations, which guide the planning and designing of the transfer facilities around subway stations.

  14. Charge Pricing Optimization Model for Private Charging Piles in Beijing

    Directory of Open Access Journals (Sweden)

    Xingping Zhang

    2017-11-01

    Full Text Available This paper develops a charge pricing model for private charging piles (PCPs by considering the environmental and economic effects of private electric vehicle (PEV charging energy sources and the impact of PCP charging load on the total load. This model simulates users’ responses to different combinations of peak-valley prices based on the charging power of PCPs and user charging transfer rate. According to the regional power structure, it calculates the real-time coal consumption, carbon dioxide emissions reduction, and power generation costs of PEVs on the power generation side. The empirical results demonstrate that the proposed peak-valley time-of-use charging price can not only minimize the peak-valley difference of the total load but also improve the environmental effects of PEVs and the economic income of the power system. The sensitivity analysis shows that the load-shifting effect of PCPs will be more obvious when magnifying the number of PEVs by using the proposed charging price. The case study indicates that the proposed peak, average, and valley price in Beijing should be 1.8, 1, and 0.4 yuan/kWh, which can promote the large-scale adoption of PEVs.

  15. A Control Algorithm for Electric Vehicle Fast Charging Stations Equipped with Flywheel Energy Storage Systems

    DEFF Research Database (Denmark)

    Sun, Bo; Dragicevic, Tomislav; Freijedo Fernandez, Francisco Daniel

    2016-01-01

    This paper proposes a control strategy for plugin electric vehicle (PEV) fast charging station (FCS) equipped with a flywheel energy storage system (FESS). The main role of the FESS is not to compromise the predefined charging profile of PEV battery during the provision of a hysteresis-type active...... power ancillary service to the overhead power system. In that sense, when the active power is not being extracted from the grid, FESS provides the power required to sustain the continuous charging process of PEV battery. A key characteristic of the whole control system is that it is able to work without...

  16. Distributed Bus Signaling Control for a DC Charging Station with Multi Paralleled Flywheel Energy Storage System

    DEFF Research Database (Denmark)

    Sun, Bo; Dragicevic, Tomislav; Vasquez, Juan Carlos

    2015-01-01

    Fast charging stations (FCS) will become an essential part of future transportation systems with an increasing number of electrical vehicles. However, since these FCS plugs have power ratings of up to 100 kW, serious stress caused by large number of FCS could threaten the stability of the main po...

  17. Modelling of an advanced charging system for electric vehicles

    Science.gov (United States)

    Hassan Jaafar, Abdul; Rahman, Ataur; Mohiuddin, A. K. M.; Rashid, Mahbubur

    2017-03-01

    Climate Change is recognized as one of the greatest environmental problem facing the World today and it has long been appreciated by governments that reducing the impact of the internal combustion (IC) engine powered motor vehicle has an important part to play in addressing this threat. In Malaysia, IC engine powered motor vehicle accounts almost 90% of the national greenhouse gas (GHG) emissions. The need to reduce the emission is paramount, as Malaysia has pledged to reduce 40% of CO2 intensity by 2020 from 2005 level by 25% of improvement in average fuel consumption. The introduction of electric vehicles (EVs) is one of the initiatives. However in terms of percentage, the electric vehicles have not been commonly used by people nowadays and one of the reasons is lack in charging infrastructure especially when cars are on the road. The aim of this study is to simulate and model an advanced charging system for the charging infrastructure of EVs/HEVs all over the nation with slow charging mode with charging current 25 A, medium charging mode with charging current 50 A and fast charging mode with charging current 100 A. The slow charging mode is proposed for residence, medium charging mode for office parking lots, and fast charging mode is called fast charging track for charging station on road. With three modes charger topology, consumers could choose a suitable mode for their car based on their need. The simulation and experiment of advanced charging system has been conducted on a scale down battery pack of nominal voltage of 3.75 V and capacity of 1020 mAh. Result shows that the battery could be charging less than 1 hour with fast charging mode. However, due to limitation of Tenaga Nasional Berhad (TNB) power grid, the maximum 50 A current is considered to be the optimized passive mode for the EV’s battery charging system. The developed advanced charger prototype performance has been compared with the simulation result and conventional charger performance, the

  18. Optimal Design of DC Fast-Charging Stations for EVs in Low Voltage Grids

    DEFF Research Database (Denmark)

    Gjelaj, Marjan; Træholt, Chresten; Hashemi Toghroljerdi, Seyedmostafa

    2017-01-01

    the design of a new DCFCS for EVs coupled with a local Battery Energy Storage (BES). DCFCS is equipped with a bidirectional AC/DC converter for feeding power back to the grid, two lithium batteries and a DC/DC converter. This paper proposes an optimal size of the BES to reduce the negative impacts...... on the power grid through the application of electrical storage systems within the DC fast charging stations. The proposed solution decreases the charging time and the impact on the low voltage (LV) grid significantly. The charger can be used as a multifunctional grid-utility such as congestion management...

  19. Fast Demand Forecast of Electric Vehicle Charging Stations for Cell Phone Application

    Energy Technology Data Exchange (ETDEWEB)

    Majidpour, Mostafa; Qiu, Charlie; Chung, Ching-Yen; Chu, Peter; Gadh, Rajit; Pota, Hemanshu R.

    2014-07-31

    This paper describes the core cellphone application algorithm which has been implemented for the prediction of energy consumption at Electric Vehicle (EV) Charging Stations at UCLA. For this interactive user application, the total time of accessing database, processing the data and making the prediction, needs to be within a few seconds. We analyze four relatively fast Machine Learning based time series prediction algorithms for our prediction engine: Historical Average, kNearest Neighbor, Weighted k-Nearest Neighbor, and Lazy Learning. The Nearest Neighbor algorithm (k Nearest Neighbor with k=1) shows better performance and is selected to be the prediction algorithm implemented for the cellphone application. Two applications have been designed on top of the prediction algorithm: one predicts the expected available energy at the station and the other one predicts the expected charging finishing time. The total time, including accessing the database, data processing, and prediction is about one second for both applications.

  20. Managing parking pressure concerns related to charging stations for electric vehicles : data analysis on the case of daytime charging in The Hague

    NARCIS (Netherlands)

    Wolbertus, R.; van den Hoed, R.

    2017-01-01

    With the rise of the number of electric vehicles, the installment of public charging infrastructure is becoming more prominent. In urban areas in which EV users rely on on-street parking facilities, the demand for public charging stations is high. Cities take on the role of implementing public

  1. DC Fast-Charging Stations for EVs Controlled by a Local Battery Storage in Low Voltage Grids

    DEFF Research Database (Denmark)

    Gjelaj, Marjan; Træholt, Chresten; Hashemi Toghroljerdi, Seyedmostafa

    2017-01-01

    is equipped with a bidirectional AC/DC converter for feeding power back to the grid, two lithium batteries and a DC/DC converter. The proposed solution decreases the charging time of EVs and facilitates the integration of fast chargers in existing low voltage (LV) grids. The charging station can also be used...... of EVs and their charging systems are going through a series of changes. This paper addresses the design of a new DC Fast Charging Station (DCFCS) for EVs coupled with a local Battery Energy Storage (BES) by using the IEC 15118, which provides a communication interface among different actors. DCFCS...

  2. Swarm Intelligence-Based Smart Energy Allocation Strategy for Charging Stations of Plug-In Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Imran Rahman

    2015-01-01

    Full Text Available Recent researches towards the use of green technologies to reduce pollution and higher penetration of renewable energy sources in the transportation sector have been gaining popularity. In this wake, extensive participation of plug-in hybrid electric vehicles (PHEVs requires adequate charging allocation strategy using a combination of smart grid systems and smart charging infrastructures. Daytime charging stations will be needed for daily usage of PHEVs due to the limited all-electric range. Intelligent energy management is an important issue which has already drawn much attention of researchers. Most of these works require formulation of mathematical models with extensive use of computational intelligence-based optimization techniques to solve many technical problems. In this paper, gravitational search algorithm (GSA has been applied and compared with another member of swarm family, particle swarm optimization (PSO, considering constraints such as energy price, remaining battery capacity, and remaining charging time. Simulation results obtained for maximizing the highly nonlinear objective function evaluate the performance of both techniques in terms of best fitness.

  3. Two-Level Control for Fast Electrical Vehicle Charging Stations with Multi Flywheel Energy Storage System

    DEFF Research Database (Denmark)

    SUN, BO; Dragicevic, Tomislav; Vasquez, Juan Carlos

    2015-01-01

    This paper applies a hierarchical control for a fast charging station (FCS) composed of paralleled PWM rectifier and dedicated paralleled multiple flywheel energy storage systems (FESSs), in order to mitigate peak power shock on grid caused by sudden connection of electrical vehicle (EV) chargers....... Distributed DC-bus signaling (DBS) and method resistive virtual impedance are employed in the power coordination of grid and flywheel converters, and a centralized secondary controller generates DC voltage correction term to adjust the local voltage set point. The control system is able to realize the power...

  4. Multi-Party Energy Management for Networks of PV-Assisted Charging Stations: A Game Theoretical Approach

    Directory of Open Access Journals (Sweden)

    Nian Liu

    2017-07-01

    Full Text Available Motivated by the development of electric vehicles (EVs, this paper addresses the energy management problem for the PV-assisted charging station (PVCS network. An hour-ahead optimization model for the operation of PVCS is proposed, considering the profit of the PVCS, the local consumption of the photovoltaic (PV energy and the impacts on the grid. Moreover, a two-level feasible charging region (FCR model is built to guarantee the service quality for EVs and learning-based decision-making is designed to assist the optimization of the PVCS in various scenarios. The multi-party energy management problem, including several kinds of energy flows of the PVCS network, is formulated as a non-cooperative game. Then, the strategies of the PVCSs are modeled as the demand response (DR activities to achieve their own optimization goals and a two-level distributed heuristic algorithm is introduced to solve the problem. The simulation results show that the economic profit of the network is increased by 6.34% compared with the common time of use (TOU prices approach. Besides, the percentage of the PV energy in total charging load (PPTCL and load rate are promoted by 28.93% and 0.3125, respectively, which demonstrates the validity and practicability of the proposed method.

  5. Provision of Flexible Load Control by Multi-Flywheel-Energy-Storage System in Electrical Vehicle Charging Stations

    DEFF Research Database (Denmark)

    Sun, Bo; Dragicevic, Tomislav; Andrade, Fabio

    2015-01-01

    Electrical vehicle (EV) chargers are going to occupy a considerable portion of total energy consumption in the future smart grid. Fast charging stations (FCS), as the most demanding representatives of charging infrastructure, will be requested to provide some ancillary services to the power system...

  6. Improved grid operation through power smoothing control strategies utilizing dedicated energy storage at an electric vehicle charging station

    DEFF Research Database (Denmark)

    Martinsen, Thomas; Holjevac, Ninoslav; Bremdal, Bernt A.

    2016-01-01

    This paper addresses the principal service aspects for electric vehicles (EV), as well as issues related to energy storage design, charging station integration into power system and load management issues. It builds on the research conducted in the Flexible Electric Vehicle Charging Infrastructure...

  7. Wind Energy Based Electric Vehicle Charging Stations Sitting. A GIS/Wind Resource Assessment Approach

    Directory of Open Access Journals (Sweden)

    George Xydis

    2015-11-01

    Full Text Available The transportation sector is severely correlated with major problems in environment, citizens’ health, climate and economy. Issues such as traffic, fuel cost and parking space have make life more difficult, especially in the dense urban environment. Thus, there is a great need for the development of the electric vehicle (EV sector. The number of cars in cities has increased so much that the current transportation system (roads, parking places, traffic lights, etc. cannot accommodate them properly. The increasing number of vehicles does not affect only humans but also the environment, through air and noise pollution. According to EPA, the 39.2% of total gas emissions in 2007 was caused by transportation activities. Studies have shown that the pollutants are not only gathered in the major roads and/or highways but can travel depending on the meteorological conditions leading to generic pollution. The promotion of EVs and the charging stations are both equally required to be further developed in order EVs to move out of the cities and finally confront the range problem. In this work, a wind resource and a GIS analysis optimizes in a wider area the sitting of wind based charging stations and proposes an optimizing methodology.

  8. Electrostatic charge bounds for ball lightning models

    Energy Technology Data Exchange (ETDEWEB)

    Stephan, Karl D [Department of Technology, Texas State University, San Marcos, TX 78666 (United States)], E-mail: kdstephan@txstate.edu

    2008-03-15

    Several current theories concerning the nature of ball lightning predict a substantial electrostatic charge in order to account for its observed motion and shape (Turner 1998 Phys. Rep. 293 1; Abrahamson and Dinniss 2000 Nature 403 519). Using charged soap bubbles as a physical model for ball lightning, we show that the magnitude of charge predicted by some of these theories is too high to allow for the types of motion commonly observed in natural ball lightning, which includes horizontal motion above the ground and movement near grounded conductors. Experiments show that at charge levels of only 10-15 nC, 3-cm-diameter soap bubbles tend to be attracted by induced charges to the nearest grounded conductor and rupture. We conclude with a scaling rule that can be used to extrapolate these results to larger objects and surroundings.

  9. Electrostatic charge bounds for ball lightning models

    Science.gov (United States)

    Stephan, Karl D.

    2008-03-01

    Several current theories concerning the nature of ball lightning predict a substantial electrostatic charge in order to account for its observed motion and shape (Turner 1998 Phys. Rep. 293 1; Abrahamson and Dinniss 2000 Nature 403 519). Using charged soap bubbles as a physical model for ball lightning, we show that the magnitude of charge predicted by some of these theories is too high to allow for the types of motion commonly observed in natural ball lightning, which includes horizontal motion above the ground and movement near grounded conductors. Experiments show that at charge levels of only 10-15 nC, 3-cm-diameter soap bubbles tend to be attracted by induced charges to the nearest grounded conductor and rupture. We conclude with a scaling rule that can be used to extrapolate these results to larger objects and surroundings.

  10. Surface Charging Controlling of the Chinese Space Station with Hollow Cathode Plasma Contactor

    Science.gov (United States)

    Jiang, Kai; Wang, Xianrong; Qin, Xiaogang; Yang, Shengsheng; Yang, Wei; Zhao, Chengxuan; Chen, Yifeng; Shi, Liang; Tang, Daotan; Xie, Kan

    2016-07-01

    A highly charged manned spacecraft threatens the life of an astronaut and extravehicular activity, which can be effectively reduced by controlling the spacecraft surface charging. In this article, the controlling of surface charging on Chinese Space Station (CSS) is investigated, and a method to reduce the negative potential to the CSS is the emission electron with a hollow cathode plasma contactor. The analysis is obtained that the high voltage (HV) solar array of the CSS collecting electron current can reach 4.5 A, which can be eliminated by emitting an adequate electron current on the CSS. The theoretical analysis and experimental results are addressed, when the minimum xenon flow rate of the hollow cathode is 4.0 sccm, the emission electron current can neutralize the collected electron current, which ensures that the potential of the CSS can be controlled in a range of less than 21 V, satisfied with safety voltage. The results can provide a significant reference value to define a flow rate to the potential controlling programme for CSS.

  11. Modelling of internal stresses in grinding charges

    OpenAIRE

    Jonsén, Pär; Pålsson, Bertil; Häggblad, Hans-Åke

    2011-01-01

    Physically realistic methods are a necessity to close the gap between reality and numerical result in modelling of tumbling mills. A problem is that tumbling mills often operate in a metastable state because of the difficulty to balance the rate of replenishment of large ore particles from the feed with the consumption in the charge. Understanding of the charge motion within the mill is of significance in mill optimisation. Both the breakage of ore particles and the wear of liners/ball media ...

  12. Distributed Cooperative Control of Multi Flywheel Energy Storage System for Electrical Vehicle Fast Charging Stations

    DEFF Research Database (Denmark)

    Sun, Bo; Dragicevic, Tomislav; Quintero, Juan Carlos Vasquez

    2015-01-01

    Plug-in electrical vehicles will play a critical role in future smart grid and sudden connection of electrical vehicles chargers may cause huge power-peaks with high slew-rates on grid. In order to cope with this issue, this paper applies a distributed cooperative control for fast charging station...... with dedicated paralleled flywheel-based energy storage system. The distributed DC-bus signaling method is employed in the power coordination of grid and flywheel converters, and a distributed secondary controller generates DC voltage correction term to adjust the local voltage set-point through a dynamic...... consensus based voltage observer by communicating with its neighbors. The control system can realize the power balancing and DC voltage regulation with low reliance on communications. Finally, real-time hardware-in-the-loop results have been reported in order to verify the feasibility of proposed approach....

  13. Intelligent energy allocation strategy for PHEV charging station using gravitational search algorithm

    Science.gov (United States)

    Rahman, Imran; Vasant, Pandian M.; Singh, Balbir Singh Mahinder; Abdullah-Al-Wadud, M.

    2014-10-01

    Recent researches towards the use of green technologies to reduce pollution and increase penetration of renewable energy sources in the transportation sector are gaining popularity. The development of the smart grid environment focusing on PHEVs may also heal some of the prevailing grid problems by enabling the implementation of Vehicle-to-Grid (V2G) concept. Intelligent energy management is an important issue which has already drawn much attention to researchers. Most of these works require formulation of mathematical models which extensively use computational intelligence-based optimization techniques to solve many technical problems. Higher penetration of PHEVs require adequate charging infrastructure as well as smart charging strategies. We used Gravitational Search Algorithm (GSA) to intelligently allocate energy to the PHEVs considering constraints such as energy price, remaining battery capacity, and remaining charging time.

  14. About the Territorial Potential of the Construction of Battery-Charging Stations for Autonomous Electric Motor Vehicles in the Regions

    Directory of Open Access Journals (Sweden)

    Shilova Lyubov

    2016-01-01

    Full Text Available The article describes the main current trends in the development of electric motor vehicles with "zero emission" as well as the battery-charging stations concerned. The study is based on a preliminary comparative analysis of the RF regions with respect to five indices (average per capita income, number of private cars in the region, air pollution level, provision of the region with power supply and the potential use of local renewable energy resources, and it gives some recommendations on the prospects of possible construction of battery-charging stations in the regions.

  15. Feasibility assessment of a solar-powered charging station for electric vehicles in the North Central region of Bulgaria

    Directory of Open Access Journals (Sweden)

    Ilieva Liliya Mihaylova

    2016-01-01

    Full Text Available The paper discusses the topical issue related to the prospects of widespread deployment of electric vehicles and their associated infrastructure in Bulgaria. The main problems hindering the development of electric vehicle transport are summarized and the current status of charging infrastructure in the country is discussed. An approach is proposed for analysis and evaluation of the financial feasibility of investment in a solar-powered charging station for electric vehicles in North Central region of Bulgaria.

  16. Development of new test methods for electric vehicles and charging stations; Entwicklung neuartiger Pruefverfahren fuer Elektrofahrzeuge und Ladesaeulen

    Energy Technology Data Exchange (ETDEWEB)

    Peitz, Michael; Matrose, Claas; Schnettler, Armin [RWTH Aachen Univ. (Germany). Inst. fuer Hochspannungstechnik; Hackmann, Markus [P3 Ingenieurgesellschaft, Aachen (Germany)

    2012-07-01

    With increasing share of electric vehicles in German traffic also their connection on low voltage grid becomes more important due to their charging process. Several concepts are available for the charging operation. One opportunity is conductive charging with cable connection, whereat in public domain often charging stations are used for coupling car, grid and consumer. In general, several normative specifications dealing with connecting electrical components to the grid, but only few are related especially to electric vehicle. However specific requirements concerning the reliability of charging process exits on electric vehicle, because an interruption of the charging process due to grid actions, can't be tolerated if the charging process only restarts due to consumer action. Hence motivated, testing procedures for system emission and immunity against electrical disturbances, especially voltage dips and interruption events, are used and developed on a test center of the Institute for High Voltage Technology (IFHT). In this paper the current state of electric testing methods and research in grid integration of vehicles and charging stations are shown and discussed. (orig.)

  17. Quantum modeling of ultrafast photoinduced charge separation

    Science.gov (United States)

    Rozzi, Carlo Andrea; Troiani, Filippo; Tavernelli, Ivano

    2018-01-01

    Phenomena involving electron transfer are ubiquitous in nature, photosynthesis and enzymes or protein activity being prominent examples. Their deep understanding thus represents a mandatory scientific goal. Moreover, controlling the separation of photogenerated charges is a crucial prerequisite in many applicative contexts, including quantum electronics, photo-electrochemical water splitting, photocatalytic dye degradation, and energy conversion. In particular, photoinduced charge separation is the pivotal step driving the storage of sun light into electrical or chemical energy. If properly mastered, these processes may also allow us to achieve a better command of information storage at the nanoscale, as required for the development of molecular electronics, optical switching, or quantum technologies, amongst others. In this Topical Review we survey recent progress in the understanding of ultrafast charge separation from photoexcited states. We report the state-of-the-art of the observation and theoretical description of charge separation phenomena in the ultrafast regime mainly focusing on molecular- and nano-sized solar energy conversion systems. In particular, we examine different proposed mechanisms driving ultrafast charge dynamics, with particular regard to the role of quantum coherence and electron-nuclear coupling, and link experimental observations to theoretical approaches based either on model Hamiltonians or on first principles simulations.

  18. Quantum modeling of ultrafast photoinduced charge separation.

    Science.gov (United States)

    Rozzi, Carlo Andrea; Troiani, Filippo; Tavernelli, Ivano

    2018-01-10

    Phenomena involving electron transfer are ubiquitous in nature, photosynthesis and enzymes or protein activity being prominent examples. Their deep understanding thus represents a mandatory scientific goal. Moreover, controlling the separation of photogenerated charges is a crucial prerequisite in many applicative contexts, including quantum electronics, photo-electrochemical water splitting, photocatalytic dye degradation, and energy conversion. In particular, photoinduced charge separation is the pivotal step driving the storage of sun light into electrical or chemical energy. If properly mastered, these processes may also allow us to achieve a better command of information storage at the nanoscale, as required for the development of molecular electronics, optical switching, or quantum technologies, amongst others. In this Topical Review we survey recent progress in the understanding of ultrafast charge separation from photoexcited states. We report the state-of-the-art of the observation and theoretical description of charge separation phenomena in the ultrafast regime mainly focusing on molecular- and nano-sized solar energy conversion systems. In particular, we examine different proposed mechanisms driving ultrafast charge dynamics, with particular regard to the role of quantum coherence and electron-nuclear coupling, and link experimental observations to theoretical approaches based either on model Hamiltonians or on first principles simulations.

  19. Problems in Modelling Charge Output Accelerometers

    Directory of Open Access Journals (Sweden)

    Tomczyk Krzysztof

    2016-12-01

    Full Text Available The paper presents major issues associated with the problem of modelling change output accelerometers. The presented solutions are based on the weighted least squares (WLS method using transformation of the complex frequency response of the sensors. The main assumptions of the WLS method and a mathematical model of charge output accelerometers are presented in first two sections of this paper. In the next sections applying the WLS method to estimation of the accelerometer model parameters is discussed and the associated uncertainties are determined. Finally, the results of modelling a PCB357B73 charge output accelerometer are analysed in the last section of this paper. All calculations were executed using the MathCad software program. The main stages of these calculations are presented in Appendices A−E.

  20. Optimal Coordinated Management of a Plug-In Electric Vehicle Charging Station under a Flexible Penalty Contract for Voltage Security

    Directory of Open Access Journals (Sweden)

    Jip Kim

    2016-07-01

    Full Text Available The increasing penetration of plug-in electric vehicles (PEVs may cause a low-voltage problem in the distribution network. In particular, the introduction of charging stations where multiple PEVs are simultaneously charged at the same bus can aggravate the low-voltage problem. Unlike a distribution network operator (DNO who has the overall responsibility for stable and reliable network operation, a charging station operator (CSO may schedule PEV charging without consideration for the resulting severe voltage drop. Therefore, there is a need for the DNO to impose a coordination measure to induce the CSO to adjust its charging schedule to help mitigate the voltage problem. Although the current time-of-use (TOU tariff is an indirect coordination measure that can motivate the CSO to shift its charging demand to off-peak time by imposing a high rate at the peak time, it is limited by its rigidity in that the network voltage condition cannot be flexibly reflected in the tariff. Therefore, a flexible penalty contract (FPC for voltage security to be used as a direct coordination measure is proposed. In addition, the optimal coordinated management is formulated. Using the Pacific Gas and Electric Company (PG&E 69-bus test distribution network, the effectiveness of the coordination was verified by comparison with the current TOU tariff.

  1. Planning Future Electric Vehicle Central Charging Stations Connected to Low-Voltage Distribution Networks

    DEFF Research Database (Denmark)

    Marra, Francesco; Træholt, Chresten; Larsen, Esben

    2012-01-01

    A great interest is recently paid to Electric Vehicles (EV) and their integration into electricity grids. EV can potentially play an important role in power system operation, however, the EV charging infrastructures have been only partly defined, considering them as limited to individual charging...... grids. The option of DC fast-charging is only possible in the larger capacity grids, withstanding the parallel charge of one or two vehicles....

  2. Optimal Site Selection of Wind-Solar Complementary Power Generation Project for a Large-Scale Plug-In Charging Station

    Directory of Open Access Journals (Sweden)

    Wenjun Chen

    2017-10-01

    Full Text Available The wind-solar hybrid power generation project combined with electric vehicle charging stations can effectively reduce the impact on the power system caused by the random charging of electric cars, contribute to the in-situ wind-solar complementary system and reduce the harm arising from its output volatility. In this paper, the site selection index system of a landscape complementary power generation project is established by using the statistical methods and statistical analysis in the literature. Subsequently, using the Analytic Network Process to calculate the index weight, a cloud model was used in combination with preference ranking organization method for enrichment evaluations to transform and sort uncertain language information. Finally, using the results of the decision-making for the location of the Shanghai wind-solar complementary project and by carrying out contrast analysis and sensitivity analysis, the superiority and stability of the decision model constructed in this study was demonstrated.

  3. Object-oriented model of railway stations operation

    Directory of Open Access Journals (Sweden)

    D.M. Kozachenko

    2013-08-01

    Full Text Available Purpose. The purpose of this article is improvement of the railway stations functional model; it leads to time expenditure cut for formalization technological processes of their work through the use of standard elements of technology. Methodology. Some technological operations, executives and technology objects are considered as main elements of the railway station functioning. Queuing techniques were used as the methods of research, simulation, finite state machines and object-oriented analysis. Findings. Formal data structures were developed as the result of research that can allow simulating the operation of the railway station with any degree of detail. In accordance with the principles of object-oriented approach in the developed model, separate elements of station technology are presented jointly with a description of their behavior. The proposed model is implemented as a software package. Originality. Functional model of railway stations was improved through the application of object-oriented approach to data management. It allow to create libraries of elementary technological processes and reduce time expenditure for formalization the technology of stations work. Practical value. Using of software package that it was developed on the base of proposed model will reduce time expenditure of technologists in order to obtain technical and operational assessment of projected and existing rail stations.

  4. Stackelberg Game Model of Wind Farm and Electric Vehicle Battery Switch Station

    Science.gov (United States)

    Jiang, Zhe; Li, Zhimin; Li, Wenbo; Wang, Mingqiang; Wang, Mengxia

    2017-05-01

    In this paper, a cooperation method between wind farm and Electric vehicle battery switch station (EVBSS) was proposed. In the pursuit of maximizing their own benefits, the cooperation between wind farm and EVBSS was formulated as a Stackelberg game model by treating them as decision makers in different status. As the leader, wind farm will determine the charging/discharging price to induce the charging and discharging behavior of EVBSS reasonably. Through peak load shifting, wind farm could increase its profits by selling more wind power to the power grid during time interval with a higher purchase price. As the follower, EVBSS will charge or discharge according to the price determined by wind farm. Through optimizing the charging /discharging strategy, EVBSS will try to charge with a lower price and discharge with a higher price in order to increase its profits. Since the possible charging /discharging strategy of EVBSS is known, the wind farm will take the strategy into consideration while deciding the charging /discharging price, and will adjust the price accordingly to increase its profits. The case study proved that the proposed cooperation method and model were feasible and effective.

  5. Overhead Costs: Costs Charged by McDonnell Douglas Aerospace’s Space Station Division

    Science.gov (United States)

    1994-06-23

    contains few limits on employee education expenses. Additional FAR coverage or other guidance on these areas may be needed. The sustention of DCAA...such as exists with the Space Station Division. Sustention of DCAA The most recent indirect expense rate negotiations completed at the Space Station

  6. Hierarchical control of a photovoltaic/battery based DC microgrid including electric vehicle wireless charging station

    DEFF Research Database (Denmark)

    Xiao, Zhao xia; Fan, Haodong; Guerrero, Josep M.

    2017-01-01

    controllers. Local controllers implement these functions, which include PV maximum power point tracking (MPPT) algorithm, battery charging/discharging control, voltage control of DC bus for high-frequency inverter, and onboard battery charging control. By optimizing and matching parameters of transmitting......In this paper, the hierarchical control strategy of a photovoltaic/battery based dc microgrid is presented for electric vehicle (EV) wireless charging. Considering irradiance variations, battery charging/discharging requirements, wireless power transmission characteristics, and onboard battery...... charging power change and other factors, the possible operation states are obtained. A hierarchical control strategy is established, which includes central and local controllers. The central controller is responsible for the selection and transfer of operation states and the management of the local...

  7. Partial Atomic Charges and Screened Charge Models of the Electrostatic Potential.

    Science.gov (United States)

    Wang, Bo; Truhlar, Donald G

    2012-06-12

    We propose a new screened charge method for calculating partial atomic charges in molecules by electrostatic potential (ESP) fitting. The model, called full density screening (FDS), is used to approximate the screening effect of full charge densities of atoms in molecules. The results are compared to the conventional ESP fitting method based on point charges and to our previously proposed outer density screening (ODS) method, in which the parameters are reoptimized for the present purpose. In ODS, the charge density of an atom is represented by the sum of a point charge and a smeared negative charge distributed in a Slater-type orbital (STO). In FDS, the charge density of an atom is taken to be the sum of the charge density of the neutral atom and a partial atomic charge (of either sign) distributed in an STO. The ζ values of the STOs used in these two models are optimized in the present study to best reproduce the electrostatic potentials. The quality of the fit to the electrostatics is improved in the screened charge methods, especially for the regions that are within one van der Waals radius of the centers of atoms. It is also found that the charges derived by fitting electrostatic potentials with screened charges are less sensitive to the positions of the fitting points than are those derived with conventional electrostatic fitting. Moreover, we found that the electrostatic-potential-fitted (ESP) charges from the screened charge methods are similar to those from the point-charge method except for molecules containing the methyl group, where we have explored the use of restraints on nonpolar H atoms. We recommend the FDS model if the only goal is ESP fitting to obtain partial atomic charges or a fit to the ESP field. However, the ODS model is more accurate for electronic embedding in combined quantum mechanical and molecular mechanical (QM/MM) modeling and is more accurate than point-charge models for ESP fitting, and it is recommended for applications

  8. Guide to Federal Funding, Financing, and Technical Assistance for Plug-in Electric Vehicles and Charging Stations

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2016-07-29

    The U.S. Department of Energy and the U.S. Department of Transportation have published a guide to highlight examples of federal support and technical assistance for plug-in electric vehicles (PEVs) and charging stations. The guide provides a description of each opportunity and a point of contact to assist those interested in advancing PEV technology. The Department of Energy’s Alternative Fuels Data Center provides a comprehensive database of federal and state programs that support plug-in electric vehicles and infrastructure.

  9. A flow model for optimization of highway toll stations

    Science.gov (United States)

    Chen, Yifan

    2017-09-01

    This paper is aimed at developing a highway toll stations route optimization model (HTSROM) for cost-effective and sustainable highway infrastructure planning and design. There are many factors for the locations of highway toll stations, including potential ridership, costs of land, construction and operation, and travel times. We developed HTSROM algorithm which used a genetic model to optimize and integrate a geographic information system for transfer of land-use, environmental, and topographic data during the optimal search process. The experimental results are discussed on the application, and more extensions of the HTSROM model remain to be studied in the future work.

  10. Modeling of charged anisotropic compact stars in general relativity

    Energy Technology Data Exchange (ETDEWEB)

    Dayanandan, Baiju; Maurya, S.K.; T, Smitha T. [University of Nizwa, Department of Mathematical and Physical Sciences, College of Arts and Science, Nizwa (Oman)

    2017-06-15

    A charged compact star model has been determined for anisotropic fluid distribution. We have solved the Einstein-Maxwell field equations to construct the charged compact star model by using the radial pressure, the metric function e{sup λ} and the electric charge function. The generic charged anisotropic solution is verified by exploring different physical conditions like causality condition, mass-radius relation and stability of the solution (via the adiabatic index, TOV equations and the Herrera cracking concept). It is observed that the present charged anisotropic compact star model is compatible with the star PSR 1937+21. Moreover, we also presented the EOS ρ = f(p) for the present charged compact star model. (orig.)

  11. Research on ISFLA-Based Optimal Control Strategy for the Coordinated Charging of EV Battery Swap Station

    Directory of Open Access Journals (Sweden)

    Xueliang Huang

    2013-01-01

    Full Text Available As an important component of the smart grid, electric vehicles (EVs could be a good measure against energy shortages and environmental pollution. A main way of energy supply to EVs is to swap battery from the swap station. Based on the characteristics of EV battery swap station, the coordinated charging optimal control strategy is investigated to smooth the load fluctuation. Shuffled frog leaping algorithm (SFLA is an optimization method inspired by the memetic evolution of a group of frogs when seeking food. An improved shuffled frog leaping algorithm (ISFLA with the reflecting method to deal with the boundary constraint is proposed to obtain the solution of the optimal control strategy for coordinated charging. Based on the daily load of a certain area, the numerical simulations including the comparison of PSO and ISFLA are carried out and the results show that the presented ISFLA can effectively lower the peak-valley difference and smooth the load profile with the faster convergence rate and higher convergence precision.

  12. Stationary Charging Station Design for Sustainable Urban Rail Systems: A Case Study at Zhuzhou Electric Locomotive Co., China

    Directory of Open Access Journals (Sweden)

    Heng Li

    2015-01-01

    Full Text Available In 2014, more than 43 cities in China were racing to construct their urban rail systems (including metro and light rail systems, recognizing that an urban rail system will be a good solution to the tough problems that they are faced with, including traffic congestion and PM2.5 air pollution. On 22 August 2012, the first electric double-layer capacitor (EDLC energy storage-type rail vehicle in the world was unveiled at Zhuzhou Electric Locomotive Co., China. The EDLC rail system has been considered a promising sustainable urban rail system, which is expected to further improve the energy efficiency and to reduce environmental pollution. The first commercial EDLC tram produced by Zhuzhou Electric Locomotive Co. has been applied at Guangzhou Metro Corp. recently. From the view point of scientific research, the system design and energy management of EDLC rail systems have been extensively studied in the literature, while the stationary charging station design for the EDLC energy storage-type urban rail vehicles has been rarely reported. Thus, the aim of this paper is to report a stationary charging station that has been successfully applied in the EDLC rail system produced by Zhuzhou Electric Locomotive Co., China.

  13. System design for a solar powered electric vehicle charging station for workplaces

    NARCIS (Netherlands)

    Chandra Mouli, G.R.; Bauer, P.; Zeman, M.

    2016-01-01

    This paper investigates the possibility of charging battery electric vehicles at workplace in Netherlands using solar energy. Data from the Dutch Meteorological Institute is used to determine the optimal orientation of PV panels for maximum energy yield in the Netherlands. The seasonal and diurnal

  14. A Heuristic for Locating Electric Vehicle Charging Stations for Trip Chains

    DEFF Research Database (Denmark)

    Wen, Min; Røpke, Stefan

    We present the problem of locating a limited number of electric vehiclecharging stations for a given set of trip chains, each of which consistsof a series of linked short trips and is represented by a sequence ofintervening stops along the trip chain. The objective of this problemis to maximize t...... the number of trip chains that can be completed by the electric vehicle without running out of battery. A mixed-integer programmingformulation as well as a heuristic for solving this problemwill be presented.......We present the problem of locating a limited number of electric vehiclecharging stations for a given set of trip chains, each of which consistsof a series of linked short trips and is represented by a sequence ofintervening stops along the trip chain. The objective of this problemis to maximize...

  15. Plug-In Electric Vehicle Fast Charge Station Operational Analysis with Integrated Renewables: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, M.; Markel, T.

    2012-08-01

    The growing, though still nascent, plug-in electric vehicle (PEV) market currently operates primarily via level 1 and level 2 charging in the United States. Fast chargers are still a rarity, but offer a confidence boost to oppose 'range anxiety' in consumers making the transition from conventional vehicles to PEVs. Because relatively no real-world usage of fast chargers at scale exists yet, the National Renewable Energy Laboratory developed a simulation to help assess fast charging needs based on real-world travel data. This study documents the data, methods, and results of the simulation run for multiple scenarios, varying fleet sizes, and the number of charger ports. The grid impact of this usage is further quantified to assess the opportunity for integration of renewables; specifically, a high frequency of fast charging is found to be in demand during the late afternoons and evenings coinciding with grid peak periods. Proper integration of a solar array and stationary battery thus helps ease the load and reduces the need for new generator construction to meet the demand of a future PEV market.

  16. Modelling the joint access mode and railway station choice

    NARCIS (Netherlands)

    Debrezion, G.; Pels, E.; Rietveld, P.

    2008-01-01

    This study models the choices of Dutch railway users. We find a steeper negative distance effect on the utility of departure stations accessed by the non-motorized modes of walking and bicycle as compared to the motorized modes of car and public transport. Availability of parking places and bicycle

  17. Screened Charge Model in the Treatment of Electrostatic Interactions

    Science.gov (United States)

    Wang, Bo; Leverentz, Hannah; Truhlar, Donald

    2012-02-01

    Partial atomic charges play an important role in molecular simulations of complex systems, and they are widely used to compute the electrostatic interactions in various methods. We propose a screened charge model to include charge penetration and screening effects in electrostatic modeling. In the screened charge model, the atomic charge density of an atom in a molecule is represented by a spherical smeared charge plus a point charge at the nucleus. The new model is illustrated for the electronically embedded combined quantum mechanical and molecular mechanical (QM/MM) calculations and for the electrostatically embedded many-body (EE-MB) method. For a test set of 40 complexes, the mean unsigned error of QM/MM electrostatic interactions between QM and MM regions is reduced from 8.1 to 2.8 kcal/mol and that for QM/MM induction interactions from 1.9 to 1.4 kcal/mol. In a test of five water hexamers, the mean unsigned error of the EE-MB binding energies of the clusters is decreased by a factor of 2 at both the pairwise additive (PA) and three-body (3B) levels. Moreover, we have found that the charges derived by fitting electrostatic potentials with the screened charge method are less sensitive to the positions of the fitting points, and the quality of the fit to the electrostatics is improved.

  18. Symmetrization of mathematical model of charge transport in semiconductors

    Directory of Open Access Journals (Sweden)

    Alexander M. Blokhin

    2002-11-01

    Full Text Available A mathematical model of charge transport in semiconductors is considered. The model is a quasilinear system of differential equations. A problem of finding an additional entropy conservation law and system symmetrization are solved.

  19. A continuum model for dynamic analysis of the Space Station

    Science.gov (United States)

    Thomas, Segun

    1989-01-01

    Dynamic analysis of the International Space Station using MSC/NASTRAN had 1312 rod elements, 62 beam elements, 489 nodes and 1473 dynamic degrees of freedom. A realtime, man-in-the-loop simulation of such a model is impractical. This paper discusses the mathematical model for realtime dynamic simulation of the Space Station. Several key questions in structures and structural dynamics are addressed. First, to achieve a significant reduction in the number of dynamic degrees of freedom, a continuum equivalent representation of the Space Station truss structure which accounted for the unsymmetry of the basic configuration and resulted in the coupling of extensional and transverse deformation, is developed. Next, dynamic equations for the continuum equivalent of the Space Station truss structure are formulated using a matrix version of Kane's dynamical equations. Flexibility is accounted for by using a theory that accommodates extension, bending in two principal planes and shear displacement. Finally, constraint equations suitable for dynamic analysis of flexible bodies with closed loop configuration are developed and solution of the resulting system of equations is based on the zero eigenvalue theorem.

  20. Improved approach for electric vehicle rapid charging station placement and sizing using Google maps and binary lightning search algorithm.

    Directory of Open Access Journals (Sweden)

    Md Mainul Islam

    Full Text Available The electric vehicle (EV is considered a premium solution to global warming and various types of pollution. Nonetheless, a key concern is the recharging of EV batteries. Therefore, this study proposes a novel approach that considers the costs of transportation loss, buildup, and substation energy loss and that incorporates harmonic power loss into optimal rapid charging station (RCS planning. A novel optimization technique, called binary lightning search algorithm (BLSA, is proposed to solve the optimization problem. BLSA is also applied to a conventional RCS planning method. A comprehensive analysis is conducted to assess the performance of the two RCS planning methods by using the IEEE 34-bus test system as the power grid. The comparative studies show that the proposed BLSA is better than other optimization techniques. The daily total cost in RCS planning of the proposed method, including harmonic power loss, decreases by 10% compared with that of the conventional method.

  1. Improved approach for electric vehicle rapid charging station placement and sizing using Google maps and binary lightning search algorithm.

    Science.gov (United States)

    Islam, Md Mainul; Shareef, Hussain; Mohamed, Azah

    2017-01-01

    The electric vehicle (EV) is considered a premium solution to global warming and various types of pollution. Nonetheless, a key concern is the recharging of EV batteries. Therefore, this study proposes a novel approach that considers the costs of transportation loss, buildup, and substation energy loss and that incorporates harmonic power loss into optimal rapid charging station (RCS) planning. A novel optimization technique, called binary lightning search algorithm (BLSA), is proposed to solve the optimization problem. BLSA is also applied to a conventional RCS planning method. A comprehensive analysis is conducted to assess the performance of the two RCS planning methods by using the IEEE 34-bus test system as the power grid. The comparative studies show that the proposed BLSA is better than other optimization techniques. The daily total cost in RCS planning of the proposed method, including harmonic power loss, decreases by 10% compared with that of the conventional method.

  2. Improved approach for electric vehicle rapid charging station placement and sizing using Google maps and binary lightning search algorithm

    Science.gov (United States)

    Shareef, Hussain; Mohamed, Azah

    2017-01-01

    The electric vehicle (EV) is considered a premium solution to global warming and various types of pollution. Nonetheless, a key concern is the recharging of EV batteries. Therefore, this study proposes a novel approach that considers the costs of transportation loss, buildup, and substation energy loss and that incorporates harmonic power loss into optimal rapid charging station (RCS) planning. A novel optimization technique, called binary lightning search algorithm (BLSA), is proposed to solve the optimization problem. BLSA is also applied to a conventional RCS planning method. A comprehensive analysis is conducted to assess the performance of the two RCS planning methods by using the IEEE 34-bus test system as the power grid. The comparative studies show that the proposed BLSA is better than other optimization techniques. The daily total cost in RCS planning of the proposed method, including harmonic power loss, decreases by 10% compared with that of the conventional method. PMID:29220396

  3. Charged excitons in doped extended Hubbard model systems

    NARCIS (Netherlands)

    van den Brink, J.; Eder, R; Sawatzky, G.A

    1997-01-01

    We show that the charge transfer excitons in a Hubbard model system including nearest-neighbor Coulomb interactions effectively attain some charge in doped systems and become visible in photoelectron and inverse photoelectron spectroscopies. This shows that the description of a doped system by an

  4. Modified Pattern Sequence-based Forecasting for Electric Vehicle Charging Stations

    Energy Technology Data Exchange (ETDEWEB)

    Majidpour, Mostafa; Qiu, Charlie; Chu, Peter; Gadh, Rajit; Pota, Hemanshu R.

    2014-11-03

    Three algorithms for the forecasting of energy consumption at individual EV charging outlets have been applied to real world data from the UCLA campus. Out of these three algorithms, namely k-Nearest Neighbor (kNN), ARIMA, and Pattern Sequence Forecasting (PSF), kNN with k=1, was the best and PSF was the worst performing algorithm with respect to the SMAPE measure. The advantage of PSF is its increased robustness to noise by substituting the real valued time series with an integer valued one, and the advantage of NN is having the least SMAPE for our data. We propose a Modified PSF algorithm (MPSF) which is a combination of PSF and NN; it could be interpreted as NN on integer valued data or as PSF with considering only the most recent neighbor to produce the output. Some other shortcomings of PSF are also addressed in the MPSF. Results show that MPSF has improved the forecast performance.

  5. ANALYSE OF ELECTROMOBILE CHARGING STATIONS FOR THE NEEEDS OF URBAN PROJECTION

    Directory of Open Access Journals (Sweden)

    Martin Straka

    2015-09-01

    Full Text Available Electrification of road vehicles is one of the basic characteristics for energy transformation in the future. An important prerequisite to this is to transform the results of research and development to many areas of practice. This includes development of efficient, affordable and practically usable accumulators or safe charging equipment and communication tools. Electromobility is a process that presents a considerable challenge for energy companies. The concept of electromobility offers a complex solution for expansion of electric vehicles and its infrastructure to be needed. There are battery manufacturers, electric vehicles manufacturers, end users, cities and countries (should provide some benefits for users of electric vehicles, as well as electricity distributors that play an important role.

  6. DETAILED MODELLING OF CHARGING BEHAVIOUR OF SMART SOLAR TANKS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Andersen, Elsa; Furbo, Simon

    2010-01-01

    The charging behaviour of smart solar tanks for solar combisystems for one-family houses is investigated with detailed Computational Fluid Dynamics (CFD) modelling and Particle Image Velocimetry (PIV) measurements. The smart solar tank can be charged with a variable auxiliary volume fitted...... or by an electric heating element in a side-arm mounted on the side of the tank. Detailed CFD models of the smart tanks are built with different mesh densities in the tank and in the side-arm. The thermal conditions of the tank during charging are calculated with the CFD models. The fluid flow and temperature...

  7. Model Predictive Control-Based Fast Charging for Vehicular Batteries

    Directory of Open Access Journals (Sweden)

    Zhibin Song

    2011-08-01

    Full Text Available Battery fast charging is one of the most significant and difficult techniques affecting the commercialization of electric vehicles (EVs. In this paper, we propose a fast charge framework based on model predictive control, with the aim of simultaneously reducing the charge duration, which represents the out-of-service time of vehicles, and the increase in temperature, which represents safety and energy efficiency during the charge process. The RC model is employed to predict the future State of Charge (SOC. A single mode lumped-parameter thermal model and a neural network trained by real experimental data are also applied to predict the future temperature in simulations and experiments respectively. A genetic algorithm is then applied to find the best charge sequence under a specified fitness function, which consists of two objectives: minimizing the charging duration and minimizing the increase in temperature. Both simulation and experiment demonstrate that the Pareto front of the proposed method dominates that of the most popular constant current constant voltage (CCCV charge method.

  8. Electrochemical model based charge optimization for lithium-ion batteries

    Science.gov (United States)

    Pramanik, Sourav; Anwar, Sohel

    2016-05-01

    In this paper, we propose the design of a novel optimal strategy for charging the lithium-ion battery based on electrochemical battery model that is aimed at improved performance. A performance index that aims at minimizing the charging effort along with a minimum deviation from the rated maximum thresholds for cell temperature and charging current has been defined. The method proposed in this paper aims at achieving a faster charging rate while maintaining safe limits for various battery parameters. Safe operation of the battery is achieved by including the battery bulk temperature as a control component in the performance index which is of critical importance for electric vehicles. Another important aspect of the performance objective proposed here is the efficiency of the algorithm that would allow higher charging rates without compromising the internal electrochemical kinetics of the battery which would prevent abusive conditions, thereby improving the long term durability. A more realistic model, based on battery electro-chemistry has been used for the design of the optimal algorithm as opposed to the conventional equivalent circuit models. To solve the optimization problem, Pontryagins principle has been used which is very effective for constrained optimization problems with both state and input constraints. Simulation results show that the proposed optimal charging algorithm is capable of shortening the charging time of a lithium ion cell while maintaining the temperature constraint when compared with the standard constant current charging. The designed method also maintains the internal states within limits that can avoid abusive operating conditions.

  9. Interaction of Charged Patchy Protein Models with Like-Charged Polyelectrolyte Brushes.

    Science.gov (United States)

    Yigit, Cemil; Kanduč, Matej; Ballauff, Matthias; Dzubiella, Joachim

    2017-01-10

    We study the adsorption of charged patchy particle models (CPPMs) on a thin film of a like-charged and dense polyelectrolyte (PE) brush (of 50 monomers per chain) by means of implicit-solvent, explicit-salt Langevin dynamics computer simulations. Our previously introduced set of CPPMs embraces well-defined one- and two-patched spherical globules, each of the same net charge and (nanometer) size, with mono- and multipole moments comparable to those of small globular proteins. We focus on electrostatic effects on the adsorption far away from the isoelectric point of typical proteins, i.e., where charge regulation plays no role. Despite the same net charge of the brush and globule, we observe large binding affinities up to tens of the thermal energy, kBT, which are enhanced by decreasing salt concentration and increasing charge of the patch(es). Our analysis of the distance-resolved potentials of mean force together with a phenomenological description of all leading interaction contributions shows that the attraction is strongest at the brush surface, driven by multipolar, Born (self-energy), and counterion-release contributions, dominating locally over the monopolar and steric repulsions.

  10. Modeling Dendrimers Charge Interaction in Solution: Relevance in Biosystems

    National Research Council Canada - National Science Library

    Lombardo, Domenico

    2014-01-01

    .... We show how the analysis of the scattering structure factor S(q), in the framework of current models for charged systems in solution, allows for obtaining important information of the interdendrimers...

  11. Modeling dendrimers charge interaction in solution: relevance in biosystems

    National Research Council Canada - National Science Library

    Lombardo, Domenico

    2014-01-01

    .... We show how the analysis of the scattering structure factor S(q), in the framework of current models for charged systems in solution, allows for obtaining important information of the interdendrimers...

  12. Energy Management and Control of Plug-In Hybrid Electric Vehicle Charging Stations in a Grid-Connected Hybrid Power System

    Directory of Open Access Journals (Sweden)

    Sidra Mumtaz

    2017-11-01

    Full Text Available The charging infrastructure plays a key role in the healthy and rapid development of the electric vehicle industry. This paper presents an energy management and control system of an electric vehicle charging station. The charging station (CS is integrated to a grid-connected hybrid power system having a wind turbine maximum power point tracking (MPPT controlled subsystem, photovoltaic (PV MPPT controlled subsystem and a controlled solid oxide fuel cell with electrolyzer subsystem which are characterized as renewable energy sources. In this article, an energy management system is designed for charging and discharging of five different plug-in hybrid electric vehicles (PHEVs simultaneously to fulfil the grid-to-vehicle (G2V, vehicle-to-grid (V2G, grid-to-battery storage system (G2BSS, battery storage system-to-grid (BSS2G, battery storage system-to-vehicle (BSS2V, vehicle-to-battery storage system (V2BSS and vehicle-to-vehicle (V2V charging and discharging requirements of the charging station. A simulation test-bed in Matlab/Simulink is developed to evaluate and control adaptively the AC-DC-AC converter of non-renewable energy source, DC-DC converters of the storage system, DC-AC grid side inverter and the converters of the CS using adaptive proportional-integral-derivate (AdapPID control paradigm. The effectiveness of the AdapPID control strategy is validated through simulation results by comparing with conventional PID control scheme.

  13. Electrodynamic Limit in a Model for Charged Solitons

    OpenAIRE

    Faber, Manfried; Kobushkin, Alexander P.

    2002-01-01

    We consider a model of topological solitons where charged particles have finite mass and the electric charge is quantised already at the classical level. In the electrodynamic limit, which physically corresponds to electrodynamics of solitons of zero size, the Lagrangian of this model has two degrees of freedom only and reduces to the Lagrangian of the Maxwell field in dual representation. We derive the equations of motion and discuss their relations with Maxwell's equations. It is shown that...

  14. An Electric Power Consumption Analysis System for the Installation of Electric Vehicle Charging Stations

    National Research Council Canada - National Science Library

    Seongpil Cheon; Suk-Ju Kang

    2017-01-01

    .... Therefore, it is difficult to calculate and predict the power load in real time. In this paper, we propose a new model for estimating the electric power consumption from the supplied information, i.e...

  15. Requirements for modeling airborne microbial contamination in space stations

    Science.gov (United States)

    Van Houdt, Rob; Kokkonen, Eero; Lehtimäki, Matti; Pasanen, Pertti; Leys, Natalie; Kulmala, Ilpo

    2018-03-01

    Exposure to bioaerosols is one of the facets that affect indoor air quality, especially for people living in densely populated or confined habitats, and is associated to a wide range of health effects. Good indoor air quality is thus vital and a prerequisite for fully confined environments such as space habitats. Bioaerosols and microbial contamination in these confined space stations can have significant health impacts, considering the unique prevailing conditions and constraints of such habitats. Therefore, biocontamination in space stations is strictly monitored and controlled to ensure crew and mission safety. However, efficient bioaerosol control measures rely on solid understanding and knowledge on how these bioaerosols are created and dispersed, and which factors affect the survivability of the associated microorganisms. Here we review the current knowledge gained from relevant studies in this wide and multidisciplinary area of bioaerosol dispersion modeling and biological indoor air quality control, specifically taking into account the specific space conditions.

  16. Techno-economic and sensitivity analysis for grid-connected renewable energy electric boat charging station in Terengganu

    Directory of Open Access Journals (Sweden)

    Salleh N. A. S.

    2017-01-01

    Full Text Available In order to encourage the eco-friendly technologies in transportation sector, the reliance on fuel need to be reduced and the use of renewable energy (RE technology as energy source are widely explored by researchers. Thus, this study focus on the feasibility of developing grid-connected renewable energy electric boat charging station for the fishermen in Terengganu using simulation-based method by HOMER software. Five year solar radiation and wind speed data were collected at Universiti Sultan Zainal Abidin (UNISZA weather station. For load profile, the information about fishing activities and the amount of subsidy spent by the government were obtained from the interview session with the fishermen and validated with Lembaga Kemajuan Ikan Malaysia (LKIM. The results acquired are compared between grid-only and grid-connected RE systems in term of net present cost (NPC, operational cost and payback period. A sensitivity analysis is done to find the minimal Feed-in Tariff (FiT rate that can be implemented in order to encourage the use of RE system in this sector. Then, the relationship between FiT and NPC, payback period and emission of pollutants are analyzed. At current FiT rates RM 0.813/kWh, hybrid grid-PV system manages to achieve its optimal in generating high income from selling the power to the grid with convincing amount of electricity production and short payback period. It is concluded at minimum RM 0.56/kWh of FiT, the grid-connected RE system is possible to be developed because its performance shows better outcome compared to the grid-only system.

  17. Charging of mobile services by mobile payment reference model

    OpenAIRE

    Pousttchi, Key; Wiedemann, Dietmar Georg

    2005-01-01

    The purpose of the paper is to analyze mobile payments in the mobile commerce scenario. Therefore, we first classify the mobile payment in the mobile commerce scenario by explaining general offer models, charging concepts, and intermediaries. Second, we describe the mobile payment reference model, especially, the mobile payment reference organization model and different mobile payment standard types. Finally, we conclude our findings.

  18. A new model for charged anisotropic compact star

    Science.gov (United States)

    Maurya, S. K.; Jasim, M. K.; Gupta, Y. K.; Smitha, T. T.

    2016-05-01

    In this paper, we have obtained a new singularity free charged anisotropic fluid solution of Einstein's field equations. The physical parameters as radial pressure, tangential pressure, energy density, charge density, electric field intensity, velocity of sound and red-shift are well behaved everywhere inside the star. The obtained compact star models can represent the observational compact objects as PSR 1937{+}21 and PSR J1614-2230.

  19. Control of Flywheel Energy Storage Systems in Electrical Vehicle Charging Stations

    DEFF Research Database (Denmark)

    Sun, Bo

    Growing environmental awareness and strong political impetus have resulted in plug-in electric vehicles (PEV) becoming ever more attractive means of transportation. They are expected to have a significant impact to the overall loading of future distribution networks. Thus, current distribution...... grids need to be updated in order to accommodate PEV fleets, which are recognized in smart grid (SG) objective. The prevailing concern in that sense is the combined impact of a large number of randomly connected PEVs in the distribution network. On the other hand, continually growing PEVs are likely...... of it as secondary layer. Control design is hence carried out by following the common principle for management of both large interconnected and small distributed generation (DG) systems. For the purpose of control optimization and parameter tuning of the primary layer, detailed modeling of grid ac/dc and FESS...

  20. Hypervelocity Impact Testing of International Space Station Meteoroid/Orbital Debris Shielding Using an Inhibited Shaped Charge Launcher

    Science.gov (United States)

    Kerr, Justin H.; Grosch, Donald

    2001-01-01

    Engineers at the NASA Johnson Space Center have conducted hypervelocity impact (HVI) performance evaluations of spacecraft meteoroid and orbital debris (M/OD) shields at velocities in excess of 7 km/s. The inhibited shaped charge launcher (ISCL), developed by the Southwest Research Institute, launches hollow, circular, cylindrical jet tips to approximately 11 km/s. Since traditional M/OD shield ballistic limit performance is defined as the diameter of sphere required to just perforate or spall a spacecraft pressure wall, engineers must decide how to compare ISCL derived data with those of the spherical impactor data set. Knowing the mass of the ISCL impactor, an equivalent sphere diameter may be calculated. This approach is conservative since ISCL jet tips are more damaging than equal mass spheres. A total of 12 tests were recently conducted at the Southwest Research Institute (SWRI) on International Space Station M/OD shields. Results of these tests are presented and compared to existing ballistic limit equations. Modification of these equations is suggested based on the results.

  1. Computer simulation study of water using a fluctuating charge model

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Hydrogen bonding in small water clusters is studied through computer simulation methods using a sophisticated, empirical model of interaction developed by Rick et al (S W Rick, S J Stuart and B J Berne 1994 J. Chem. Phys. 101 6141) and others. The model allows for the charges on the interacting sites to ...

  2. Numerical modelling of electrochemical polarization around charged metallic particles

    Science.gov (United States)

    Bücker, Matthias; Undorf, Sabine; Flores Orozco, Adrián; Kemna, Andreas

    2017-04-01

    We extend an existing analytical model and carry out numerical simulations to study the polarization process around charged metallic particles immersed in an electrolyte solution. Electro-migration and diffusion processes in the electrolyte are described by the Poisson-Nernst-Planck system of partial differential equations. To model the surface charge density, we consider a time- and frequency-invariant electric potential at the particle surface, which leads to the build-up of a static electrical double layer (EDL). Upon excitation by an external electric field at low frequencies, we observe the superposition of two polarization processes. On the one hand, the induced dipole moment on the metallic particle leads to the accumulation of opposite charges in the electrolyte. This charge polarization corresponds to the long-known response of uncharged metallic particles. On the other hand, the unequal cation and anion concentrations in the EDL give rise to a salinity gradient between the two opposite sides of the metallic particle. The resulting concentration polarization enhances the magnitude of the overall polarization response. Furthermore, we use our numerical model to study the effect of relevant model parameters such as surface charge density and ionic strength of the electrolyte on the resulting spectra of the effective conductivity of the composite model system. Our results do not only give interesting new insight into the time-harmonic variation of electric potential and ion concentrations around charged metallic particle. They are also able to reduce incongruities between earlier model predictions and geophysical field and laboratory measurements. Our model thereby improves the general understanding of IP signatures of metallic particles and represents the next step towards a quantitative interpretation of IP imaging results. Part of this research is funded by the Austrian Federal Ministry of Science, Research and Economy under the Raw Materials Initiative.

  3. Charge Reduction Potentials of Several Refrigerants Based on Experimentally Validated Micro-Channel Heat Exchangers Performance and Charge Model

    OpenAIRE

    Padilla Fuentes, Yadira; Hrnjak, Predrag S.

    2012-01-01

    This paper presents an experimentally validated simulation model developed to obtain accurate prediction of evaporator microchannel heat exchanger performance and charge. Effects of using various correlations are presented and discussed with focus on serpentine microchannel evaporators. Experiments with propane are used to validate the model. The experimentally validated model is used to compare the charge reduction potential of various refrigerants. The procedure for charge reduction analysi...

  4. Solid charged-core model of ball lightning

    Directory of Open Access Journals (Sweden)

    D. B. Muldrew

    2010-01-01

    Full Text Available In this study, ball lightning (BL is assumed to have a solid, positively-charged core. According to this underlying assumption, the core is surrounded by a thin electron layer with a charge nearly equal in magnitude to that of the core. A vacuum exists between the core and the electron layer containing an intense electromagnetic (EM field which is reflected and guided by the electron layer. The microwave EM field applies a ponderomotive force (radiation pressure to the electrons preventing them from falling into the core. The energetic electrons ionize the air next to the electron layer forming a neutral plasma layer. The electric-field distributions and their associated frequencies in the ball are determined by applying boundary conditions to a differential equation given by Stratton (1941. It is then shown that the electron and plasma layers are sufficiently thick and dense to completely trap and guide the EM field. This model of BL is exceptional in that it can explain all or nearly all of the peculiar characteristics of BL. The ES energy associated with the core charge can be extremely large which can explain the observations that occasionally BL contains enormous energy. The mass of the core prevents the BL from rising like a helium-filled balloon – a problem with most plasma and burning-gas models. The positively charged core keeps the negatively charged electron layer from diffusing away, i.e. it holds the ball together; other models do not have a mechanism to do this. The high electrical charges on the core and in the electron layer explains why some people have been electrocuted by BL. Experiments indicate that BL radiates microwaves upon exploding and this is consistent with the model. The fact that this novel model of BL can explain these and other observations is strong evidence that the model should be taken seriously.

  5. Solid charged-core model of ball lightning

    Science.gov (United States)

    Muldrew, D. B.

    2010-01-01

    In this study, ball lightning (BL) is assumed to have a solid, positively-charged core. According to this underlying assumption, the core is surrounded by a thin electron layer with a charge nearly equal in magnitude to that of the core. A vacuum exists between the core and the electron layer containing an intense electromagnetic (EM) field which is reflected and guided by the electron layer. The microwave EM field applies a ponderomotive force (radiation pressure) to the electrons preventing them from falling into the core. The energetic electrons ionize the air next to the electron layer forming a neutral plasma layer. The electric-field distributions and their associated frequencies in the ball are determined by applying boundary conditions to a differential equation given by Stratton (1941). It is then shown that the electron and plasma layers are sufficiently thick and dense to completely trap and guide the EM field. This model of BL is exceptional in that it can explain all or nearly all of the peculiar characteristics of BL. The ES energy associated with the core charge can be extremely large which can explain the observations that occasionally BL contains enormous energy. The mass of the core prevents the BL from rising like a helium-filled balloon - a problem with most plasma and burning-gas models. The positively charged core keeps the negatively charged electron layer from diffusing away, i.e. it holds the ball together; other models do not have a mechanism to do this. The high electrical charges on the core and in the electron layer explains why some people have been electrocuted by BL. Experiments indicate that BL radiates microwaves upon exploding and this is consistent with the model. The fact that this novel model of BL can explain these and other observations is strong evidence that the model should be taken seriously.

  6. Charged current universality in the minimal supersymmetric standard model.

    Science.gov (United States)

    Kurylov, A; Ramsey-Musolf, M J

    2002-02-18

    We compute the complete one-loop contributions to low-energy charged current weak interaction observables in the minimal supersymmetric standard model (MSSM). We obtain the constraints on the MSSM parameter space which arise when precision low-energy charged current data are analyzed in tandem with measurements of the muon anomaly. While the data allow the presence of at least one light neutralino, they also imply a pattern of mass splittings among first and second generation sleptons and squarks which contradicts predictions of widely used models for supersymmetry-breaking mediation.

  7. Modeling, hybridization, and optimal charging of electrical energy storage systems

    Science.gov (United States)

    Parvini, Yasha

    The rising rate of global energy demand alongside the dwindling fossil fuel resources has motivated research for alternative and sustainable solutions. Within this area of research, electrical energy storage systems are pivotal in applications including electrified vehicles, renewable power generation, and electronic devices. The approach of this dissertation is to elucidate the bottlenecks of integrating supercapacitors and batteries in energy systems and propose solutions by the means of modeling, control, and experimental techniques. In the first step, the supercapacitor cell is modeled in order to gain fundamental understanding of its electrical and thermal dynamics. The dependence of electrical parameters on state of charge (SOC), current direction and magnitude (20-200 A), and temperatures ranging from -40°C to 60°C was embedded in this computationally efficient model. The coupled electro-thermal model was parameterized using specifically designed temporal experiments and then validated by the application of real world duty cycles. Driving range is one of the major challenges of electric vehicles compared to combustion vehicles. In order to shed light on the benefits of hybridizing a lead-acid driven electric vehicle via supercapacitors, a model was parameterized for the lead-acid battery and combined with the model already developed for the supercapacitor, to build the hybrid battery-supercapacitor model. A hardware in the loop (HIL) setup consisting of a custom built DC/DC converter, micro-controller (muC) to implement the power management strategy, 12V lead-acid battery, and a 16.2V supercapacitor module was built to perform the validation experiments. Charging electrical energy storage systems in an efficient and quick manner, motivated to solve an optimal control problem with the objective of maximizing the charging efficiency for supercapacitors, lead-acid, and lithium ion batteries. Pontryagins minimum principle was used to solve the problems

  8. Applications of the International Space Station Probabilistic Risk Assessment Model

    Science.gov (United States)

    Grant, Warren; Lutomski, Michael G.

    2011-01-01

    Recently the International Space Station (ISS) has incorporated more Probabilistic Risk Assessments (PRAs) in the decision making process for significant issues. Future PRAs will have major impact to ISS and future spacecraft development and operations. These PRAs will have their foundation in the current complete ISS PRA model and the current PRA trade studies that are being analyzed as requested by ISS Program stakeholders. ISS PRAs have recently helped in the decision making process for determining reliability requirements for future NASA spacecraft and commercial spacecraft, making crew rescue decisions, as well as making operational requirements for ISS orbital orientation, planning Extravehicular activities (EVAs) and robotic operations. This paper will describe some applications of the ISS PRA model and how they impacted the final decision. This paper will discuss future analysis topics such as life extension, requirements of new commercial vehicles visiting ISS.

  9. Applicability of an exposure model for the determination of emissions from mobile phone base stations

    DEFF Research Database (Denmark)

    Breckenkamp, J; Neitzke, H P; Bornkessel, C

    2008-01-01

    Applicability of a model to estimate radiofrequency electromagnetic field (RF-EMF) strength in households from mobile phone base stations was evaluated with technical data of mobile phone base stations available from the German Net Agency, and dosimetric measurements, performed...

  10. Charge diffusion in the one-dimensional Hubbard model

    OpenAIRE

    Steinigeweg, R.; Jin, F; De Raedt, H.; Michielsen, K.; Gemmer, J.

    2017-01-01

    We study the real-time and real-space dynamics of charge in the one-dimensional Hubbard model in the limit of high temperatures. To this end, we prepare pure initial states with sharply peaked density profiles and calculate the time evolution of these nonequilibrium states, by using numerical forward-propagation approaches to chains as long as 20 sites. For a class of typical states, we find excellent agreement with linear-response theory and unveil the existence of remarkably clean charge di...

  11. The Recharging Infrastructure Needs for Long Distance Travel by Electric Vehicles: A Comparison of Battery-Switching and Quick-Charging Stations

    DEFF Research Database (Denmark)

    Christensen, Linda; Jensen, Thomas Christian; Kaplan, Sigal

    2017-01-01

    of 1–2% of the current gasoline infrastructure, under the assumption of wide availability of off-road recharging at home and the workplace; (iii) the optimal deployment of the recharging stations is along the main national highways outside of urban conurbations, under the assumption of wide...... availability of home recharging; (iv) the battery-switching technology is far more attractive to the consumer than the quick-charging technology for long-distance travel requiring more than one recharging visit....

  12. Model for Charge Transport in Ferroelectric Nanocomposite Film

    Directory of Open Access Journals (Sweden)

    Meng H. Lean

    2015-01-01

    Full Text Available This paper describes 3D particle-in-cell simulation of charge injection and transport through nanocomposite film comprised of ferroelectric ceramic nanofillers in an amorphous polymer matrix and/or semicrystalline ferroelectric polymer with varying degrees of crystallinity. The classical electrical double layer model for a monopolar core is extended to represent the nanofiller/nanocrystallite by replacing it with a dipolar core. Charge injection at the electrodes assumes metal-polymer Schottky emission at low to moderate fields and Fowler-Nordheim tunneling at high fields. Injected particles propagate via field-dependent Poole-Frenkel mobility. The simulation algorithm uses a boundary integral equation method for solution of the Poisson equation coupled with a second-order predictor-corrector scheme for robust time integration of the equations of motion. The stability criterion of the explicit algorithm conforms to the Courant-Friedrichs-Levy limit assuring robust and rapid convergence. Simulation results for BaTiO3 nanofiller in amorphous polymer matrix and semicrystalline PVDF with varying degrees of crystallinity indicate that charge transport behavior depends on nanoparticle polarization with antiparallel orientation showing the highest conduction and therefore the lowest level of charge trapping in the interaction zone. Charge attachment to nanofillers and nanocrystallites increases with vol% loading or degree of crystallinity and saturates at 30–40 vol% for the set of simulation parameters.

  13. Quantitative Risk Modeling of Fire on the International Space Station

    Science.gov (United States)

    Castillo, Theresa; Haught, Megan

    2014-01-01

    The International Space Station (ISS) Program has worked to prevent fire events and to mitigate their impacts should they occur. Hardware is designed to reduce sources of ignition, oxygen systems are designed to control leaking, flammable materials are prevented from flying to ISS whenever possible, the crew is trained in fire response, and fire response equipment improvements are sought out and funded. Fire prevention and mitigation are a top ISS Program priority - however, programmatic resources are limited; thus, risk trades are made to ensure an adequate level of safety is maintained onboard the ISS. In support of these risk trades, the ISS Probabilistic Risk Assessment (PRA) team has modeled the likelihood of fire occurring in the ISS pressurized cabin, a phenomenological event that has never before been probabilistically modeled in a microgravity environment. This paper will discuss the genesis of the ISS PRA fire model, its enhancement in collaboration with fire experts, and the results which have informed ISS programmatic decisions and will continue to be used throughout the life of the program.

  14. Modelling blast induced damage from a fully coupled explosive charge

    Science.gov (United States)

    Onederra, Italo A.; Furtney, Jason K.; Sellers, Ewan; Iverson, Stephen

    2015-01-01

    This paper presents one of the latest developments in the blasting engineering modelling field—the Hybrid Stress Blasting Model (HSBM). HSBM includes a rock breakage engine to model detonation, wave propagation, rock fragmentation, and muck pile formation. Results from two controlled blasting experiments were used to evaluate the code’s ability to predict the extent of damage. Results indicate that the code is capable of adequately predicting both the extent and shape of the damage zone associated with the influence of point-of-initiation and free-face boundary conditions. Radial fractures extending towards a free face are apparent in the modelling output and matched those mapped after the experiment. In the stage 2 validation experiment, the maximum extent of visible damage was of the order of 1.45 m for the fully coupled 38-mm emulsion charge. Peak radial velocities were predicted within a relative difference of only 1.59% at the nearest history point at 0.3 m from the explosive charge. Discrepancies were larger further away from the charge, with relative differences of −22.4% and −42.9% at distances of 0.46 m and 0.61 m, respectively, meaning that the model overestimated particle velocities at these distances. This attenuation deficiency in the modelling produced an overestimation of the damage zone at the corner of the block due to excessive stress reflections. The extent of visible damage in the immediate vicinity of the blasthole adequately matched the measurements. PMID:26412978

  15. Partial Model of Insulator/Insulator Contact Charging

    Science.gov (United States)

    Hogue, Michael; Calle, C. I.; Buhler, C. R.; Mucciolo, E. R.

    2005-01-01

    Two papers present a two-phase equilibrium model that partly explains insulator/ insulator contact charging. In this model, a vapor of ions within a gas is in equilibrium with a submonolayer of ions of the same species that have been adsorbed on the surface of an insulator. The surface is modeled as having localized states, each with a certain energy of adsorption for an ion. In an earlier version of the model described in the first paper, the ions do not interact with each other. Using the grand canonical ensemble, the chemical potentials of both vapor and absorbed phases are derived and equated to determine the vapor pressure. If a charge is assigned to the vapor particles (in particular, if single ionization is assumed), then the surface charge density associated with adsorbed ions can be calculated as a function of pressure. In a later version of the model presented in the second paper, the submodel of the vapor phase is extended to include electrostatic interactions between vapor ions and adsorbed ones as well as the screening effect, at a given distance from the surface, of ions closer to the surface. Theoretical values of this model closely match preliminary experimental data on the discharge of insulators as a function of pressure.

  16. Spin and charge fluctuations in the Hubbard model

    Science.gov (United States)

    Sherman, A.

    2017-10-01

    Using the strong coupling diagram technique for calculating the electron Green's function of the two-dimensional Hubbard model we have summed infinite sequences of ladder diagrams, which describe interactions of electrons with spin and charge fluctuations. For sufficiently low temperatures and doping a pronounced four-band structure is observed in spectral functions. Its appearance is related to the proximity of the transition to the long-range antiferromagnetic order.

  17. Optimal Siting of Charging Stations for Electric Vehicles Based on Fuzzy Delphi and Hybrid Multi-Criteria Decision Making Approaches from an Extended Sustainability Perspective

    Directory of Open Access Journals (Sweden)

    Huiru Zhao

    2016-04-01

    Full Text Available Optimal siting of electric vehicle charging stations (EVCSs is crucial to the sustainable development of electric vehicle systems. Considering the defects of previous heuristic optimization models in tackling subjective factors, this paper employs a multi-criteria decision-making (MCDM framework to address the issue of EVCS siting. The initial criteria for optimal EVCS siting are selected from extended sustainability theory, and the vital sub-criteria are further determined by using a fuzzy Delphi method (FDM, which consists of four pillars: economy, society, environment and technology perspectives. To tolerate vagueness and ambiguity of subjective factors and human judgment, a fuzzy Grey relation analysis (GRA-VIKOR method is employed to determine the optimal EVCS site, which also improves the conventional aggregating function of fuzzy Vlsekriterijumska Optimizacijia I Kompromisno Resenje (VIKOR. Moreover, to integrate the subjective opinions as well as objective information, experts’ ratings and Shannon entropy method are employed to determine combination weights. Then, the applicability of proposed framework is demonstrated by an empirical study of five EVCS site alternatives in Tianjin. The results show that A3 is selected as the optimal site for EVCS, and sub-criteria affiliated with environment obtain much more attentions than that of other sub-criteria. Moreover, sensitivity analysis indicates the selection results remains stable no matter how sub-criteria weights are changed, which verifies the robustness and effectiveness of proposed model and evaluation results. This study provides a comprehensive and effective method for optimal siting of EVCS and also innovates the weights determination and distance calculation for conventional fuzzy VIKOR.

  18. Modeling Dendrimers Charge Interaction in Solution: Relevance in Biosystems

    Directory of Open Access Journals (Sweden)

    Domenico Lombardo

    2014-01-01

    Full Text Available Dendrimers are highly branched macromolecules obtained by stepwise controlled, reaction sequences. The ability to be designed for specific applications makes dendrimers unprecedented components to control the structural organization of matter during the bottom-up synthesis of functional nanostructures. For their applications in the field of biotechnology the determination of dendrimer structural properties as well as the investigation of the specific interaction with guest components are needed. We show how the analysis of the scattering structure factor S(q, in the framework of current models for charged systems in solution, allows for obtaining important information of the interdendrimers electrostatic interaction potential. The finding of the presented results outlines the important role of the dendrimer charge and the solvent conditions in regulating, through the modulation of the electrostatic interaction potential, great part of the main structural properties. This charge interaction has been indicated by many studies as a crucial factor for a wide range of structural processes involving their biomedical application. Due to their easily controllable properties dendrimers can be considered at the crossroad between traditional colloids, associating polymers, and biological systems and represent then an interesting new technological approach and a suitable model system of molecular organization in biochemistry and related fields.

  19. A Unified Channel Charges Expression for Analytic MOSFET Modeling

    Directory of Open Access Journals (Sweden)

    Hugues Murray

    2012-01-01

    Full Text Available Based on a 1D Poissons equation resolution, we present an analytic model of inversion charges allowing calculation of the drain current and transconductance in the Metal Oxide Semiconductor Field Effect Transistor. The drain current and transconductance are described by analytical functions including mobility corrections and short channel effects (CLM, DIBL. The comparison with the Pao-Sah integral shows excellent accuracy of the model in all inversion modes from strong to weak inversion in submicronics MOSFET. All calculations are encoded with a simple C program and give instantaneous results that provide an efficient tool for microelectronics users.

  20. Charge diffusion in the one-dimensional Hubbard model

    Science.gov (United States)

    Steinigeweg, R.; Jin, F.; De Raedt, H.; Michielsen, K.; Gemmer, J.

    2017-08-01

    We study the real-time and real-space dynamics of charge in the one-dimensional Hubbard model in the limit of high temperatures. To this end, we prepare pure initial states with sharply peaked density profiles and calculate the time evolution of these nonequilibrium states, by using numerical forward-propagation approaches to chains as long as 20 sites. For a class of typical states, we find excellent agreement with linear-response theory and unveil the existence of remarkably clean charge diffusion in the regime of strong particle-particle interactions. We additionally demonstrate that, in the half-filling sector, this diffusive behavior does not depend on certain details of our initial conditions, i.e., it occurs for five different realizations with random and nonrandom internal degrees of freedom, single and double occupation of the central site, and displacement of spin-up and spin-down particles.

  1. Modeling Framework and Results to Inform Charging Infrastructure Investments

    Energy Technology Data Exchange (ETDEWEB)

    Melaina, Marc W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wood, Eric W [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-01

    The plug-in electric vehicle (PEV) market is experiencing rapid growth with dozens of battery electric (BEV) and plug-in hybrid electric (PHEV) models already available and billions of dollars being invested by automotive manufacturers in the PEV space. Electric range is increasing thanks to larger and more advanced batteries and significant infrastructure investments are being made to enable higher power fast charging. Costs are falling and PEVs are becoming more competitive with conventional vehicles. Moreover, new technologies such as connectivity and automation hold the promise of enhancing the value proposition of PEVs. This presentation outlines a suite of projects funded by the U.S. Department of Energy's Vehicle Technology Office to conduct assessments of the economic value and charging infrastructure requirements of the evolving PEV market. Individual assessments include national evaluations of PEV economic value (assuming 73M PEVs on the road in 2035), national analysis of charging infrastructure requirements (with community and corridor level resolution), and case studies of PEV ownership in Columbus, OH and Massachusetts.

  2. Space charge templates for high-current beam modeling

    Energy Technology Data Exchange (ETDEWEB)

    Vorobiev, Leonid G.; /Fermilab

    2008-07-01

    A computational method to evaluate space charge potential and gradients of charged particle beam in the presence of conducting boundaries, has been introduced. The three-dimensional (3D) field of the beam can be derived as a convolution of macro Green's functions (template fields), satisfying the same boundary conditions, as the original beam. Numerical experiments gave a confidence that space charge effects can be modeled by templates with enough accuracy and generality within dramatically faster computational times than standard combination: a grid density + Poisson solvers, realized in the most of Particle in Cell codes. The achieved rapidity may significantly broaden the high-current beam design space, making the optimization in automatic mode possible, which so far was only feasible for simplest self-field formulations such as rms envelope equations. The template technique may be used as a standalone program, or as an optional field solver in existing beam dynamics codes both in one-passage structures and in rings.

  3. Charge Exchange: Velocity Dependent X-ray Emission Modeling

    Science.gov (United States)

    Cumbee, Renata

    2017-06-01

    Atomic collisions play a fundamental role in astrophysics, plasma physics, and fusion physics. Here, we focus on charge exchange (CX) between hot ions and neutral atoms and molecules. Even though charge exchange calculations can provide vital information, including neutral and ion density distributions, ion temperatures, elemental abundances, and ion charge state distributions in the environments considered, both theoretical calculations and laboratory studies of these processes lack the necessary reliability and/or coverage. In order to better understand the spectra we observe in astrophysical environments in which both hot plasma and neutral gas are present, including comets, the heliosphere, supernova remnants, galaxy clusters, star forming galaxies, the outflows of starburst galaxies, and cooling flows of hot gas in the intracluster medium, a thorough CX X-ray model is needed. Included in this model should be a complete set of X-ray line ratios for relevant ion and neutral interactions for a range of energies.In this work, theoretical charge exchange emission spectra are produced using cross sections calculated with widely applied approaches including the quantum mechanical molecular orbital close coupling (QMOCC), atomic orbital close coupling (AOCC), classical trajectory Monte Carlo (CTMC), and the multichannel Landau-Zener (MCLZ) methods. When possible, theoretical data are benchmarked to experiments. Using a comprehensive, but still far from complete, CX database, new models are performed for a variety of X-ray emitting environments. In an attempt to describe the excess emission in X-rays of the starburst galaxy M82, Ne X CX line ratios are compared to line ratios observed in the region. A more complete XSPEC X-ray emission model is produced for H-like and He-like C-Al ions colliding with H and He for a range of energies; 200 to 5000 eV/u. This model is applied to the northeast rim of the Cygnus Loop supernova remnant in an attempt to determine the

  4. Study on Impact of Electric Vehicles Charging Models on Power Load

    Science.gov (United States)

    Cheng, Chen; Hui-mei, Yuan

    2017-05-01

    With the rapid increase in the number of electric vehicles, which will lead the power load on grid increased and have an adversely affect. This paper gives a detailed analysis of the following factors, such as scale of the electric cars, charging mode, initial charging time, initial state of charge, charging power and other factors. Monte Carlo simulation method is used to compare the two charging modes, which are conventional charging and fast charging, and MATLAB is used to model and simulate the electric vehicle charging load. The results show that compared with the conventional charging mode, fast charging mode can meet the requirements of fast charging, but also bring great load to the distribution network which will affect the reliability of power grid.

  5. CPM : A Deformable Model for Shape Recovery and Segmentation Based on Charged Particles

    NARCIS (Netherlands)

    Jalba, Andrei C.; Wilkinson, Michael H.F.; Roerdink, Jos B.T.M.

    2004-01-01

    A novel, physically motivated deformable model for shape recovery and segmentation is presented. The model, referred to as the charged-particle model (CPM), is inspired by classical electrodynamics and is based on a simulation of charged particles moving in an electrostatic field. The charges are

  6. Statistical modelling of monthly mean sea level at coastal tide gauge stations along the Indian subcontinent

    Digital Repository Service at National Institute of Oceanography (India)

    Srinivas, K.; Das, V.K.; DineshKumar, P.K.

    This study investigates the suitability of statistical models for their predictive potential for the monthly mean sea level at different stations along the west and east coasts of the Indian subcontinent. Statistical modelling of the monthly mean...

  7. Routing Trains through railway stations: model formulation and algorithms

    NARCIS (Netherlands)

    P.J. Zwaneveld (Peter); L.G. Kroon (Leo); H.E. Romeijn (Edwin); M. Salomon (Marc); S. Dauzere-Peres; S. van Hoesel (Stan); H.W. Ambergen

    1996-01-01

    textabstractIn this paper we consider the problem of routing trains through railway stations. This problem occurs as a subproblem in a project which the authors are carrying out in cooperation with the Dutch railways. The project involves the analysis of future infrastructural capacity requirements

  8. Modelling nanofluidic field amplified sample stacking with inhomogeneous surface charge

    Science.gov (United States)

    McCallum, Christopher; Pennathur, Sumita

    2015-11-01

    Nanofluidic technology has exceptional applications as a platform for biological sample preconcentration, which will allow for an effective electronic detection method of low concentration analytes. One such preconcentration method is field amplified sample stacking, a capillary electrophoresis technique that utilizes large concentration differences to generate high electric field gradients, causing the sample of interest to form a narrow, concentrated band. Field amplified sample stacking has been shown to work well at the microscale, with models and experiments confirming expected behavior. However, nanofluidics allows for further concentration enhancement due to focusing of the sample ions toward the channel center by the electric double layer. We have developed a two-dimensional model that can be used for both micro- and nanofluidics, fully accounting for the electric double layer. This model has been used to investigate even more complex physics such as the role of inhomogeneous surface charge.

  9. Flexible Local Load Controller for Fast ElectricVehicle Charging Station Supplemented with Flywheel Energy Storage System

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; SUN, BO; Schaltz, Erik

    2014-01-01

    Electric vehicle charging infrastructure is hitting the stage where its impact on performance and operation of power systems becomes more and more pronounced. Aiming to utilize the existing power distribution infrastructure and delay its expansion, an approach that includes installation of dedica...

  10. Measurements and modelling of base station power consumption under real traffic loads.

    Science.gov (United States)

    Lorincz, Josip; Garma, Tonko; Petrovic, Goran

    2012-01-01

    Base stations represent the main contributor to the energy consumption of a mobile cellular network. Since traffic load in mobile networks significantly varies during a working or weekend day, it is important to quantify the influence of these variations on the base station power consumption. Therefore, this paper investigates changes in the instantaneous power consumption of GSM (Global System for Mobile Communications) and UMTS (Universal Mobile Telecommunications System) base stations according to their respective traffic load. The real data in terms of the power consumption and traffic load have been obtained from continuous measurements performed on a fully operated base station site. Measurements show the existence of a direct relationship between base station traffic load and power consumption. According to this relationship, we develop a linear power consumption model for base stations of both technologies. This paper also gives an overview of the most important concepts which are being proposed to make cellular networks more energy-efficient.

  11. Measurements and Modelling of Base Station Power Consumption under Real Traffic Loads

    Directory of Open Access Journals (Sweden)

    Goran Petrovic

    2012-03-01

    Full Text Available Base stations represent the main contributor to the energy consumption of a mobile cellular network. Since traffic load in mobile networks significantly varies during a working or weekend day, it is important to quantify the influence of these variations on the base station power consumption. Therefore, this paper investigates changes in the instantaneous power consumption of GSM (Global System for Mobile Communications and UMTS (Universal Mobile Telecommunications System base stations according to their respective traffic load. The real data in terms of the power consumption and traffic load have been obtained from continuous measurements performed on a fully operated base station site. Measurements show the existence of a direct relationship between base station traffic load and power consumption. According to this relationship, we develop a linear power consumption model for base stations of both technologies. This paper also gives an overview of the most important concepts which are being proposed to make cellular networks more energy-efficient.

  12. A Massless-Point-Charge Model for the Electron

    Directory of Open Access Journals (Sweden)

    Daywitt W. C.

    2010-04-01

    Full Text Available "It is rather remarkable that the modern concept of electrodynamics is not quite 100 years old and yet still does not rest firmly upon uniformly accepted theoretical foundations. Maxwell's theory of the electromagnetic field is firmly ensconced in modern physics, to be sure, but the details of how charged particles are to be coupled to this field remain somewhat uncertain, despite the enormous advances in quantum electrodynamics over the past 45 years. Our theories remain mathematically ill-posed and mired in conceptual ambiguities which quantum mechanics has only moved to another arena rather than resolve. Fundamentally, we still do not understand just what is a charged particle" (Grandy W.T. Jr. Relativistic quantum mechanics of leptons and fields. Kluwer Academic Publishers, Dordrecht-London, 1991, p.367. As a partial answer to the preceeding quote, this paper presents a new model for the electron that combines the seminal work of Puthoff with the theory of the Planck vacuum (PV, the basic idea for the model following from Puthoff with the PV theory adding some important details.

  13. Validation of an ANN Flow Prediction Model Using a Multt-Station Cluster Analysis

    NARCIS (Netherlands)

    Demirel, M.C.; Booij, Martijn J.; Kahya, E.

    2012-01-01

    The objective of this study is to validate a flow prediction model for a hydrometric station using a multistation criterion in addition to standard single-station performance criteria. In this contribution we used cluster analysis to identify the regional flow height, i.e., water-level patterns and

  14. A model and simulation of fast space charge pulses in polymers

    Science.gov (United States)

    Lv, Zepeng; Rowland, Simon M.; Wu, Kai

    2017-11-01

    The transport of space charge packets across polyethylene and epoxy resin in high electric fields has been characterized as fast or slow depending on packet mobility. Several explanations for the formation and transport of slow space charge packets have been proposed, but the origins of fast space charge pulses, with mobilities above 10-11 m2 V-1 s-1, are unclear. In one suggested model, it is assumed that the formation of fast charge pulses is due to discontinuous electromechanical compression and charge injection at the electrode-insulation interface, and their transport is related to corresponding relaxation processes. In that model, charges travel as a pulse because of group polarization. This paper provides an alternative model based on the reduction of charge carrier activation energy due to charge density triggered polymer chain movement and subsequent chain relaxation times. The generation and transport of fast charge pulses are readily simulated by a bipolar charge transport model with three additional parameters: reduced activation energy, charge density threshold, and chain relaxation time. Such a model is shown to reproduce key features of fast space charge pulses including speed, duration, repetition rate and pulse size. This model provides the basis for a deep understanding of the physical origins of fast space charge pulses in polymers.

  15. Charging Guidance of Electric Taxis Based on Adaptive Particle Swarm Optimization.

    Science.gov (United States)

    Niu, Liyong; Zhang, Di

    2015-01-01

    Electric taxis are playing an important role in the application of electric vehicles. The actual operational data of electric taxis in Shenzhen, China, is analyzed, and, in allusion to the unbalanced time availability of the charging station equipment, the electric taxis charging guidance system is proposed basing on the charging station information and vehicle information. An electric taxis charging guidance model is established and guides the charging based on the positions of taxis and charging stations with adaptive mutation particle swarm optimization. The simulation is based on the actual data of Shenzhen charging stations, and the results show that electric taxis can be evenly distributed to the appropriate charging stations according to the charging pile numbers in charging stations after the charging guidance. The even distribution among the charging stations in the area will be achieved and the utilization of charging equipment will be improved, so the proposed charging guidance method is verified to be feasible. The improved utilization of charging equipment can save public charging infrastructure resources greatly.

  16. Charging Guidance of Electric Taxis Based on Adaptive Particle Swarm Optimization

    Science.gov (United States)

    Niu, Liyong; Zhang, Di

    2015-01-01

    Electric taxis are playing an important role in the application of electric vehicles. The actual operational data of electric taxis in Shenzhen, China, is analyzed, and, in allusion to the unbalanced time availability of the charging station equipment, the electric taxis charging guidance system is proposed basing on the charging station information and vehicle information. An electric taxis charging guidance model is established and guides the charging based on the positions of taxis and charging stations with adaptive mutation particle swarm optimization. The simulation is based on the actual data of Shenzhen charging stations, and the results show that electric taxis can be evenly distributed to the appropriate charging stations according to the charging pile numbers in charging stations after the charging guidance. The even distribution among the charging stations in the area will be achieved and the utilization of charging equipment will be improved, so the proposed charging guidance method is verified to be feasible. The improved utilization of charging equipment can save public charging infrastructure resources greatly. PMID:26236770

  17. Operations of electric taxis to serve advance reservations by trip chaining: Sensitivity analysis on network size, customer demand and number of charging stations

    Directory of Open Access Journals (Sweden)

    Hao Wang

    2016-10-01

    Full Text Available This research investigated the performance of an Electric Taxi (ET fleet that catered solely for customers with advance reservations. In a previously related research, a customized Paired Pickup and Delivery Problem with Time Window and Charging Station (PPDPTWCS had been formulated to solve for the minimum number of taxis that would serve a fixed set of customer demand. The concept behind this fleet optimization was to chain multiple customer trips and trips to Charging Stations (CSs to form a route and assigned to a taxi driver. In this paper the sensitivity of the ET fleet’s operations with respect to network sizes, customer demand densities and number of CSs have been investigated. It also analyzed the market shares of the CSs and the occupancy of a CS over time. The results showed that, (1 the expansion of network size or the increase in customer demand density led to increase in fleet size, number of trips to the CSs and maximum occupancies at the CSs but these performance measures grew at different rates; (2 when the network size and number of CSs were fixed, an increase in customer demand density led to a better utilization of taxis in terms of more customers served per taxi and higher average revenue per taxi; (3 given the same network size and demand density, the ET fleet’s performance was relatively insensitive to the number of CSs; and (4 the usage of individual CS was affected by the number of CS and their locations; and (5 when all the ETs were fully charged at the beginning of the same shift hour, they visited the CSs in bunches when their batteries were about to run out. These findings contribute to a better understanding of the operations of the ET fleet and the CSs. They could be used for making better decisions in the planning of ET operations.

  18. Modeling energy and charge transports in pi-conjugated systems

    Science.gov (United States)

    Shin, Yongwoo

    Carbon based pi-conjugated materials, such as conducting polymers, fullerene, carbon nanotubes, graphene, and conjugated dendrimers have attracted wide scientific attentions in the past three decades. This work presents the first unified model Hamiltonian that can accurately capture the low-energy excitations among all these pi-conjugated systems, even with the presence of defects and heterogeneous sites. Two transferable physical parameters are incorporated into the Su-Schrieffer-Heeger Hamiltonian to model conducting polymers beyond polyacetylene: the parameter gamma scales the electronphonon coupling strength in aromatic rings and the other parameter epsilon specifies the heterogeneous core charges. This generic Hamiltonian predicts the fundamental band gaps of polythiophene, polypyrrole, polyfuran, poly-(p-phenylene), poly-(p-phenylene vinylene), polyacenes, fullerene, carbon nanotubes, graphene, and graphene nanoribbons with an accuracy exceeding time-dependent density functional theory. Its computational costs for moderate-length polymer chains are more than eight orders of magnitude lower than first-principles approaches. The charge and energy transports along -conjugated backbones can be modeled on the adiabatic potential energy surface. The adiabatic minimum-energy path of a self-trapped topological soliton is computed for trans-polyacetylene. The frequently cited activation barrier via a ridge shift of the hyper-tangent order parameter overestimates its true value by 14 orders of magnitude. Self-trapped solitons migrate along the Goldstone mode direction with continuously adjusted amplitudes so that a small-width soliton expands and a large-width soliton shrinks when they move uphill. A soliton with the critical width may migrate without any amplitude modifications. In an open chain as solitons move from the chain center toward a chain edge, the minimum-energy path first follows a tilted washboard. Such a generic constrained Goldstone mode relaxation

  19. Universal response model for a corona charged aerosol detector.

    Science.gov (United States)

    Hutchinson, Joseph P; Li, Jianfeng; Farrell, William; Groeber, Elizabeth; Szucs, Roman; Dicinoski, Greg; Haddad, Paul R

    2010-11-19

    The universality of the response of the Corona Charged Aerosol Detector (CoronaCAD) has been investigated under flow-injection and gradient HPLC elution conditions. A three-dimensional model was developed which relates the CoronaCAD response to analyte concentration and the mobile phase composition used. The model was developed using the response of four probe analytes which displayed non-volatile behavior in the CoronaCAD and were soluble over a broad range of mobile phase compositions. The analyte concentrations ranged from 1μg/mL to 1mg/mL, and injection volumes corresponded to on-column amounts of 25ng to 25μg. Mobile phases used in the model were composed of 0-80% acetonitrile, mixed with complementary proportions of aqueous formic acid (0.1%, pH 2.6). An analyte set of 23 compounds possessing a wide range of physicochemical properties was selected for the purpose of evaluating the model. The predicted response was compared to the actual analyte response displayed by the detector and the efficacy of the model under flow-injection and gradient HPLC elution conditions was determined. The average error of the four analytes used to develop the model was 9.2% (n=176), while the errors under flow-injection and gradient HPLC elution conditions for the evaluation set of analytes were found to be 12.5% and 12.8%, respectively. Some analytes were excluded from the evaluation set due to considerations of volatility (boiling point <400°C), charge and excessive retention on the column leading to elution outside the eluent range covered by the model. The two-part response model can be used to describe the relationship between response and analyte concentration and also to offer a correction for the non-linear detector response obtained with gradient HPLC for analytes which conform to the model, to provide insight into the factors affecting the CoronaCAD response for different analytes, and also as a means for accurately determining the concentration of unknown compounds

  20. Discrete element method modeling of the triboelectric charging of polyethylene particles: Can particle size distribution and segregation reduce the charging?

    Science.gov (United States)

    Konopka, Ladislav; Kosek, Juraj

    2015-10-01

    Polyethylene particles of various sizes are present in industrial gas-dispersion reactors and downstream processing units. The contact of the particles with a device wall as well as the mutual particle collisions cause electrons on the particle surface to redistribute in the system. The undesirable triboelectric charging results in several operational problems and safety risks in industrial systems, for example in the fluidized-bed polymerization reactor. We studied the charging of polyethylene particles caused by the particle-particle interactions in gas. Our model employs the Discrete Element Method (DEM) describing the particle dynamics and incorporates the ‘Trapped Electron Approach’ as the physical basis for the considered charging mechanism. The model predicts the particle charge distribution for systems with various particle size distributions and various level of segregation. Simulation results are in a qualitative agreement with experimental observations of similar particulate systems specifically in two aspects: 1) Big particles tend to gain positive charge and small particles the negative one. 2) The wider the particle size distribution is, the more pronounced is the charging process. Our results suggest that not only the size distribution, but also the effect of the spatial segregation of the polyethylene particles significantly influence the resulting charge distribution ‘generated’ in the system. The level of particle segregation as well as the particle size distribution of polyethylene particles can be in practice adjusted by the choice of supported catalysts, by the conditions in the fluidized-bed polymerization reactor and by the fluid dynamics. We also attempt to predict how the reactor temperature affects the triboelectric charging of particles.

  1. Mathematical model for estimating of technical and technological indicators of railway stations operation

    Directory of Open Access Journals (Sweden)

    D.M. Kozachenko

    2013-06-01

    Full Text Available Purpose. The article aims to create a mathematical model of the railway station functioning for the solving of problems of station technology development on the plan-schedule basis. Methodology. The methods of graph theory and object-oriented analysis are used as research methods. The model of the station activity plan-schedule includes a model of technical equipment of the station (plan-schedule net and a model of the station functioning , which are formalized on the basis of parametric graphs. Findings. The presented model is implemented as an application to the graphics package AutoCAD. The software is developed in Visual LISP and Visual Basic. Taking into account that the construction of the plan-schedule is mostly a traditional process of adding, deleting, and modifying of icons, the developed interface is intuitively understandable for a technologist and practically does not require additional training. Originality. A mathematical model was created on the basis of the theory of graphs and object-oriented analysis in order to evaluate the technical and process of railway stations indicators; it is focused on solving problems of technology development of their work. Practical value. The proposed mathematical model is implemented as an application to the graphics package of AutoCAD. The presence of a mathematical model allows carrying out an automatic analysis of the plan-schedule and, thereby, reducing the period of its creation more than twice.

  2. Effects of gas types and models on optimized gas fuelling station reservoir's pressure

    Directory of Open Access Journals (Sweden)

    M. Farzaneh-Gord

    2013-06-01

    Full Text Available There are similar algorithms and infrastructure for storing gas fuels at CNG (Compressed Natural Gas and CHG (Compressed Hydrogen Gas fuelling stations. In these stations, the fuels are usually stored in the cascade storage system to utilize the stations more efficiently. The cascade storage system generally divides into three reservoirs, commonly termed low, medium and high-pressure reservoirs. The pressures within these reservoirs have huge effects on performance of the stations. In the current study, based on the laws of thermodynamics, conservation of mass and real/ideal gas assumptions, a theoretical analysis has been constructed to study the effects of gas types and models on performance of the stations. It is intended to determine the optimized reservoir pressures for these stations. The results reveal that the optimized pressure differs between the gas types. For ideal and real gas models in both stations (CNG and CHG, the optimized non-dimensional low pressure-reservoir pressure is found to be 0.22. The optimized non-dimensional medium-pressure reservoir pressure is the same for the stations, and equal to 0.58.

  3. Synthetic Optimization Model and Algorithm for Railway Freight Center Station Location and Wagon Flow Organization Problem

    Directory of Open Access Journals (Sweden)

    Xing-cai Liu

    2014-01-01

    Full Text Available The railway freight center stations location and wagon flow organization in railway transport are interconnected, and each of them is complicated in a large-scale rail network. In this paper, a two-stage method is proposed to optimize railway freight center stations location and wagon flow organization together. The location model is present with the objective to minimize the operation cost and fixed construction cost. Then, the second model of wagon flow organization is proposed to decide the optimal train service between different freight center stations. The location of the stations is the output of the first model. A heuristic algorithm that combined tabu search (TS with adaptive clonal selection algorithm (ACSA is proposed to solve those two models. The numerical results show the proposed solution method is effective.

  4. Electric vehicle charge planning using Economic Model Predictive Control

    DEFF Research Database (Denmark)

    Halvgaard, Rasmus; Poulsen, Niels K.; Madsen, Henrik

    2012-01-01

    Economic Model Predictive Control (MPC) is very well suited for controlling smart energy systems since electricity price and demand forecasts are easily integrated in the controller. Electric vehicles (EVs) are expected to play a large role in the future Smart Grid. They are expected to provide...... grid services, both for peak reduction and for ancillary services, by absorbing short term variations in the electricity production. In this paper the Economic MPC minimizes the cost of electricity consumption for a single EV. Simulations show savings of 50–60% of the electricity costs compared...... to uncontrolled charging from load shifting based on driving pattern predictions. The future energy system in Denmark will most likely be based on renewable energy sources e.g. wind and solar power. These green energy sources introduce stochastic fluctuations in the electricity production. Therefore, energy...

  5. Modeling the Flux-Charge Relation of Memristor with Neural Network of Smooth Hinge Functions

    Directory of Open Access Journals (Sweden)

    X. Mu

    2014-09-01

    Full Text Available The memristor was proposed to characterize the flux-charge relation. We propose the generalized flux-charge relation model of memristor with neural network of smooth hinge functions. There is effective identification algorithm for the neural network of smooth hinge functions. The representation capability of this model is theoretically guaranteed. Any functional flux-charge relation of a memristor can be approximated by the model. We also give application examples to show that the given model can approximate the flux-charge relation of existing piecewise linear memristor model, window function memristor model, and a physical memristor device.

  6. The BDS Triple Frequency Pseudo-range Correlated Stochastic Model of Single Station Modeling Method

    Directory of Open Access Journals (Sweden)

    HUANG Lingyong

    2017-05-01

    Full Text Available In order to provide a reliable pseudo-range stochastic model, a method is studied to estimate the BDS triple-frequency pseudo-range related stochastic model based on three BDS triple-frequency pseudo-range minus carrier (GIF combinations using the data of a single station. In this algorithm, the low order polynomial fitting method is used to fit the GIF combination in order to eliminate the error and other constants except non pseudo noise at first. And then, multiple linear regression analysis method is used to model the stochastic function of three linearly independent GIF combinations. Finally the related stochastic model of the original BDS triple-frequency pseudo-range observations is obtained by linear transformation. The BDS triple-frequency data verification results show that this algorithm can get a single station related stochastic model of BDS triple-frequency pseudo-range observation, and it is advantageous to provide accurate stochastic model for navigation and positioning and integrity monitoring.

  7. Regional travel-time residual studies and station correction from 1-D velocity models for some stations around Peninsular Malaysia and Singapore

    Directory of Open Access Journals (Sweden)

    Abel U. Osagie

    2017-06-01

    Full Text Available We have investigated the average P-wave travel-time residuals for some stations around Southern Thailand, Peninsular Malaysia and Singapore at regional distances. Six years (January, 2010–December, 2015 record of events from central and northern Sumatra was obtained from the digital seismic archives of Integrated Research Institute for Seismology (IRIS. The criteria used for the data selection are designed to be above the magnitude of mb 4.5, depth less than 200 km and an epicentral distance shorter than 1000 km. Within this window a total number of 152 earthquakes were obtained. Furthermore, data were filtered based on the clarity of the seismic phases that are manually picked. A total of 1088 P-wave arrivals and 962 S-wave arrivals were hand-picked from 10 seismic stations around the Peninsula. Three stations IPM, KUM, and KOM from Peninsular Malaysia, four stations BTDF, NTU, BESC and KAPK from Singapore and three stations SURA, SRIT and SKLT located in the southern part of Thailand are used. Station NTU was chosen as the Ref. station because it recorded the large number of events. Travel-times were calculated using three 1-D models (Preliminary Ref. Earth Model PREM (Dziewonski and Anderson, 1981, IASP91, and Lienert et al., 1986 and an adopted two-point ray tracing algorithm. For the three models, we corroborate our calculated travel-times with the results from the use of TAUP travel-time calculation software. Relative to station NTU, our results show that the average P wave travel-time residual for PREM model ranges from −0.16 to 0.45 s for BESC and IPM respectively. For IASP91 model, the average residual ranges from −0.25 to 0.24 s for SRIT and SKLT respectively, and ranges from −0.22 to 0.30 s for KAPK and IPM respectively for Lienert et al. (1986 model. Generally, most stations have slightly positive residuals relative to station NTU. These corrections reflect the difference between actual and estimated model velocities

  8. Regional travel-time residual studies and station correction from 1-D velocity models for some stations around Peninsular Malaysia and Singapore

    Science.gov (United States)

    Osagie, Abel U.; Nawawi, Mohd.; Khalil, Amin Esmail; Abdullah, Khiruddin

    2017-06-01

    We have investigated the average P-wave travel-time residuals for some stations around Southern Thailand, Peninsular Malaysia and Singapore at regional distances. Six years (January, 2010-December, 2015) record of events from central and northern Sumatra was obtained from the digital seismic archives of Integrated Research Institute for Seismology (IRIS). The criteria used for the data selection are designed to be above the magnitude of mb 4.5, depth less than 200 km and an epicentral distance shorter than 1000 km. Within this window a total number of 152 earthquakes were obtained. Furthermore, data were filtered based on the clarity of the seismic phases that are manually picked. A total of 1088 P-wave arrivals and 962 S-wave arrivals were hand-picked from 10 seismic stations around the Peninsula. Three stations IPM, KUM, and KOM from Peninsular Malaysia, four stations BTDF, NTU, BESC and KAPK from Singapore and three stations SURA, SRIT and SKLT located in the southern part of Thailand are used. Station NTU was chosen as the Ref. station because it recorded the large number of events. Travel-times were calculated using three 1-D models (Preliminary Ref. Earth Model PREM (Dziewonski and Anderson, 1981, IASP91, and Lienert et al., 1986) and an adopted two-point ray tracing algorithm. For the three models, we corroborate our calculated travel-times with the results from the use of TAUP travel-time calculation software. Relative to station NTU, our results show that the average P wave travel-time residual for PREM model ranges from -0.16 to 0.45 s for BESC and IPM respectively. For IASP91 model, the average residual ranges from -0.25 to 0.24 s for SRIT and SKLT respectively, and ranges from -0.22 to 0.30 s for KAPK and IPM respectively for Lienert et al. (1986) model. Generally, most stations have slightly positive residuals relative to station NTU. These corrections reflect the difference between actual and estimated model velocities along ray paths to stations and

  9. Railway Container Station Reselection Approach and Application: Based on Entropy-Cloud Model

    Directory of Open Access Journals (Sweden)

    Wencheng Huang

    2017-01-01

    Full Text Available Reasonable railway container freight stations layout means higher transportation efficiency and less transportation cost. To obtain more objective and accurate reselection results, a new entropy-cloud approach is formulated to solve the problem. The approach comprises three phases: Entropy Method is used to obtain the weight of each subcriterion during Phase  1, then cloud model is designed to form the evaluation cloud for each subcriterion during Phase  2, and finally during Phase  3 we use the weight during Phase  1 to multiply the initial evaluation cloud during Phase  2. MATLAB is applied to determine the evaluation figures and help us to make the final alternative decision. To test our approach, the railway container stations in Wuhan Railway Bureau were selected for our case study. The final evaluation result indicates only Xiangyang Station should be renovated and developed as a Special Transaction Station, five other stations should be kept and developed as Ordinary Stations, and the remaining 16 stations should be closed. Furthermore, the results show that, before the site reselection process, the average distance between two railway container stations was only 74.7 km but has improved to 182.6 km after using the approach formulated in this paper.

  10. Modeling track access charge to enhance railway industry performance

    Science.gov (United States)

    Berawi, Mohammed Ali; Miraj, Perdana; Berawi, Abdur Rohim Boy; Susantono, Bambang; Leviakangas, Pekka; Radiansyah, Hendra

    2017-11-01

    Indonesia attempts to improve nation's competitiveness by increasing the quality and the availability of railway network. However, the infrastructure improperly managed by the operator in terms of the technical issue. One of the reasons for this problem is an unbalanced value of infrastructure charge. In 2000's track access charge and infrastructure maintenance and operation for Indonesia railways are equal and despite current formula of the infrastructure charge, issues of transparency and accountability still in question. This research aims to produce an alternative scheme of track access charge by considering marginal cost plus markup (MC+) approach. The research combines qualitative and quantitative method through an in-depth interview and financial analysis. The result will generate alternative formula of infrastructure charge in Indonesia's railway industry. The simulation also conducted to estimate track access charge for the operator and to forecast government support in terms of subsidy. The result is expected to enhance railway industry performance and competitiveness.

  11. Assessment of Charging Infrastructure for Plug-in Electric Vehicles at Naval Air Station Whidbey Island: Task 3

    Energy Technology Data Exchange (ETDEWEB)

    Schey, Steve [Idaho National Lab. (INL), Idaho Falls, ID (United States); Francfort, Jim [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-07-01

    Several U.S. Department of Defense base studies have been conducted to identify potential U.S. Department of Defense transportation systems that are strong candidates for introduction or expansion of plug-in electric vehicles (PEVs). Task 1 consisted of a survey of the non-tactical fleet of vehicles at NASWI to begin the review of vehicle mission assignments and types of vehicles in service. Task 2 selected vehicles for further monitoring and involved identifying daily operational characteristics of these select vehicles. Data logging of vehicle movements was initiated in order to characterize the vehicle’s mission. The Task 3 Vehicle Utilization report provided the results of the data analysis and observations related to the replacement of current vehicles with PEVs. This report provides an assessment of charging infrastructure required to support the suggested PEV replacements.

  12. Polaron assisted charge transfer in model biological systems

    Science.gov (United States)

    Li, Guangqi; Movaghar, Bijan

    2016-11-01

    We use a tight binding Hamiltonian to simulate the electron transfer from an initial charge-separating exciton to a final target state through a two-arm transfer model. The structure is copied from the model frequently used to describe electron harvesting in photosynthesis (photosystems I). We use this network to provide proof of principle for dynamics, in quantum system/bath networks, especially those involving interference pathways, and use these results to make predictions on artificially realizable systems. Each site is coupled to the phonon bath via several electron-phonon couplings. The assumed large energy gaps and weak tunneling integrals linking the last 3 sites give rise to"Stark Wannier like" quantum localization; electron transfer to the target cluster becomes impossible without bath coupling. As a result of the electron-phonon coupling, local electronic energies relax when the site is occupied, and transient polaronic states are formed as photo-generated electrons traverse the system. For a symmetric constructively interfering two pathway network, the population is shared equally between two sets of equivalent sites and therefore the polaron energy shift is smaller. The smaller energy shift however makes the tunnel transfer to the last site slower or blocks it altogether. Slight disorder (or thermal noise) can break the symmetry, permitting essentially a "one path", and correspondingly more efficient transfer.

  13. Charged and neutral minimal supersymmetric standard model Higgs ...

    Indian Academy of Sciences (India)

    the derivation of tan β from these measurements. 2. Discovery limits for charged and neutral MSSM Higgs bosons at CLIC. In e+e− collisions, charged and neutral Higgs bosons can be produced in pairs via an intermediate photon or Z boson. At CLIC, prior to the initial state radia- tion of photons (ISR), one must take into ...

  14. Screening model for nanowire surface-charge sensors in liquid

    DEFF Research Database (Denmark)

    Sørensen, Martin Hedegård; Mortensen, Asger; Brandbyge, Mads

    2007-01-01

    The conductance change of nanowire field-effect transistors is considered a highly sensitive probe for surface charge. However, Debye screening of relevant physiological liquid environments challenge device performance due to competing screening from the ionic liquid and nanowire charge carriers....

  15. Workplace Charging. Charging Up University Campuses

    Energy Technology Data Exchange (ETDEWEB)

    Giles, Carrie [ICF International, Fairfax, VA (United States); Ryder, Carrie [ICF International, Fairfax, VA (United States); Lommele, Stephen [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-03-01

    This case study features the experiences of university partners in the U.S. Department of Energy's (DOE) Workplace Charging Challenge with the installation and management of plug-in electric vehicle (PEV) charging stations.

  16. Numerical modeling and monitoring analysis of Heroísmo station, Metro do Porto

    DEFF Research Database (Denmark)

    Ferreira, P.; Sousa, T.; Silva, P.

    2007-01-01

    Metro do Porto is a major light rail infrastructure built in the city of Porto and surrounding municipalities. In Porto's downtown, classified by UNESCO as World Heritage, the metro was built underground. From a technical point of view, one of the most challenging underground metro stations due...... of the granite formations were given by the designer and also obtained through the software GEOPAT. The models' outputs were compared with the monitored results in order to validate the structural behaviour of the underground station....

  17. Automatic localization of IASLC-defined mediastinal lymph node stations on CT images using fuzzy models

    Science.gov (United States)

    Matsumoto, Monica M. S.; Beig, Niha G.; Udupa, Jayaram K.; Archer, Steven; Torigian, Drew A.

    2014-03-01

    Lung cancer is associated with the highest cancer mortality rates among men and women in the United States. The accurate and precise identification of the lymph node stations on computed tomography (CT) images is important for staging disease and potentially for prognosticating outcome in patients with lung cancer, as well as for pretreatment planning and response assessment purposes. To facilitate a standard means of referring to lymph nodes, the International Association for the Study of Lung Cancer (IASLC) has recently proposed a definition of the different lymph node stations and zones in the thorax. However, nodal station identification is typically performed manually by visual assessment in clinical radiology. This approach leaves room for error due to the subjective and potentially ambiguous nature of visual interpretation, and is labor intensive. We present a method of automatically recognizing the mediastinal IASLC-defined lymph node stations by modifying a hierarchical fuzzy modeling approach previously developed for body-wide automatic anatomy recognition (AAR) in medical imagery. Our AAR-lymph node (AAR-LN) system follows the AAR methodology and consists of two steps. In the first step, the various lymph node stations are manually delineated on a set of CT images following the IASLC definitions. These delineations are then used to build a fuzzy hierarchical model of the nodal stations which are considered as 3D objects. In the second step, the stations are automatically located on any given CT image of the thorax by using the hierarchical fuzzy model and object recognition algorithms. Based on 23 data sets used for model building, 22 independent data sets for testing, and 10 lymph node stations, a mean localization accuracy of within 1-6 voxels has been achieved by the AAR-LN system.

  18. A model of charge collection for irradiated p sup + n detectors

    CERN Document Server

    Martí i García, S; Casse, G; Greenall, A

    2001-01-01

    The charge collection in irradiated p sup + n silicon detectors was studied as a function of the reverse bias voltage. Oxygenated and non-oxygenated devices were irradiated beyond type inversion with 24 GeV/c protons. The charge collection is successfully described with a model based on the hypothesis that the charge trapping depends on the carriers velocity. With this model, values for the full depletion voltage are extracted which show good agreement with those measured using the CV technique. The model allows a quantitative understanding of why although oxygenation of p sup + n devices improves substantially the full depletion voltage, much less improvement is observed in the charge collection efficiency.

  19. Morphological Analysis on Business Model of Electric Vehicles Charging Infrastructure in China

    DEFF Research Database (Denmark)

    Li, Suxiu; Liu, Yingqi; Wang, Jingyu

    2016-01-01

    plays a big role in the process of EVs industrialization. Based on the morphological box of EVs charging infrastructure business model aboard proposed by foreign scholars Kley etc., and considering the status quo of EVs charging infrastructure in China, this paper finally builds a morphological box...... of EVs charging infrastructure business model for China, and takes the city Shenzhen as a case study. The research shows that we can achieve EVs Charging infrastructure business model innovation by combining design possibility on the right side of morphological box as much as possible....

  20. Navy Enlistment Supply Model at the Recruiting Station Level

    National Research Council Canada - National Science Library

    McRoberts, Claude M

    2008-01-01

    ... their proposed theoretical relationships. The purpose of this study is to utilize factors common to previous research along with the additional factors of proximity to military installations and high school quality to build the best predictive model...

  1. Assessment of Atomic Charge Models for Gas-Phase Computations on Polypeptides.

    Science.gov (United States)

    Verstraelen, Toon; Pauwels, Ewald; De Proft, Frank; Van Speybroeck, Veronique; Geerlings, Paul; Waroquier, Michel

    2012-02-14

    The concept of the atomic charge is extensively used to model the electrostatic properties of proteins. Atomic charges are not only the basis for the electrostatic energy term in biomolecular force fields but are also derived from quantum mechanical computations on protein fragments to get more insight into their electronic structure. Unfortunately there are many atomic charge schemes which lead to significantly different results, and it is not trivial to determine which scheme is most suitable for biomolecular studies. Therefore, we present an extensive methodological benchmark using a selection of atomic charge schemes [Mulliken, natural, restrained electrostatic potential, Hirshfeld-I, electronegativity equalization method (EEM), and split-charge equilibration (SQE)] applied to two sets of penta-alanine conformers. Our analysis clearly shows that Hirshfeld-I charges offer the best compromise between transferability (robustness with respect to conformational changes) and the ability to reproduce electrostatic properties of the penta-alanine. The benchmark also considers two charge equilibration models (EEM and SQE), which both clearly fail to describe the locally charged moieties in the zwitterionic form of penta-alanine. This issue is analyzed in detail because charge equilibration models are computationally much more attractive than the Hirshfeld-I scheme. Based on the latter analysis, a straightforward extension of the SQE model is proposed, SQE+Q(0), that is suitable to describe biological systems bearing many locally charged functional groups.

  2. Image charge effects in the nonequilibrium Anderson-Holstein model

    Science.gov (United States)

    Perfetto, E.; Stefanucci, G.

    2013-12-01

    Image charge effects in nanoscale junctions with strong electron-phonon coupling open the way to unexplored physical scenarios. We propose a simple and still accurate many-body approach to deal with the simultaneous occurrence of the Franck-Condon blockade and the screening-induced enhancement of the polaron mobility. A transparent analytic expression for the polaron decay rate is derived and the dependence on the strength and range of the screening is highlighted. This allows us to interpret and explain several transient and steady-state features of the electrical current. Remarkably, we find that the competition between the charge blocking due to the electron-phonon interaction and the charge deblocking due to the image charges gives rise to a novel mechanism of negative differential conductance. An experimental setup to observe this phenomenon is discussed.

  3. Poisson-Boltzmann model of electrolytes containing uniformly charged spherical nanoparticles.

    Science.gov (United States)

    Bohinc, Klemen; Volpe Bossa, Guilherme; Gavryushov, Sergei; May, Sylvio

    2016-12-21

    Like-charged macromolecules typically repel each other in aqueous solutions that contain small mobile ions. The interaction tends to turn attractive if mobile ions with spatially extended charge distributions are added. Such systems can be modeled within the mean-field Poisson-Boltzmann formalism by explicitly accounting for charge-charge correlations within the spatially extended ions. We consider an aqueous solution that contains a mixture of spherical nanoparticles with uniform surface charge density and small mobile salt ions, sandwiched between two like-charged planar surfaces. We perform the minimization of an appropriate free energy functional, which leads to a non-linear integral-differential equation for the electrostatic potential that we solve numerically and compare with predictions from Monte Carlo simulations. Nanoparticles with uniform surface charge density are contrasted with nanoparticles that have all their charges relocated at the center. Our mean-field model predicts that only the former (especially when large and highly charged particles) but not the latter are able to mediate attractive interactions between like-charged planar surfaces. We also demonstrate that at high salt concentration attractive interactions between like-charged planar surfaces turn into repulsion.

  4. Modelling indoor electromagnetic fields (EMF) from mobile phone base stations for epidemiological studies

    NARCIS (Netherlands)

    Beekhuizen, J.; Vermeulen, R.; van Eijsden, M.; van Strien, R.; Bürgi, A.; Loomans, E.; Guxens, M.; Kromhout, H.; Huss, A.

    2014-01-01

    Radio frequency electromagnetic fields (RF-EMF) from mobile phone base stations can be reliably modelled for outdoor locations, using 3D radio wave propagation models that consider antenna characteristics and building geometry. For exposure assessment in epidemiological studies, however, it is

  5. Stochastic modelling of train delays and delay propagation in stations

    NARCIS (Netherlands)

    Yuan, J.

    2006-01-01

    A trade-off exists between efficiently utilizing the capacity of railway networks and improving the reliability and punctuality of train operations. This dissertation presents a new analytical probability model based on blocking time theory which estimates the knock-on delays of trains caused by

  6. Charge of the Electron, and the Constants of Radiation According to J. A. Wheeler's Geometrodynamic Model

    Directory of Open Access Journals (Sweden)

    Belyakov A. V.

    2010-10-01

    Full Text Available This study suggests a mechanical interpretation of Wheller’s model of the charge. Ac- cording to the suggested interpretation, the oppositely charged particles are connected through the vortical lines of the current thus create a close contour “input-output” whose parameters determine the properties of the charge and spin. Depending on the energetic state of the system, the contour can be structurized into the units of the second and thirs order (photons. It is found that, in the framework of this interpretation, the charge is equivalent to the momentum. The numerical value of the unit charge has also been cal- culated proceeding from this basis. A system of the relations, connecting the charge to the constants of radiation (the Boltzmann, Wien, and Stefan-Boltzmann constants, and the fine structure constant has been obtained: this give a possibility for calculating all these constants through the unit charge.

  7. Modeling and Optimization of Collaborative Passenger Control in Urban Rail Stations under Mass Passenger Flow

    Directory of Open Access Journals (Sweden)

    Lili Wang

    2015-01-01

    Full Text Available With the rapid development of urban rail transit, the phenomenon of outburst passenger flows flocking to stations is occurring much more frequently. Passenger flow control is one of the main methods used to ensure passengers’ safety. While most previous studies have only focused on control measures inside the target station, ignoring the collaboration between stops, this paper puts emphasis on joint passenger control methods during the occurrence of large passenger flows. To provide a theoretic description for the problem under consideration, an integer programming model is built, based on the analysis of passenger delay and the processes by which passengers alight and board. Taking average passenger delay as the objective, the proposed model aims to disperse the pressure of oversaturated stations into others, achieving the optimal state for the entire line. The model is verified using a case study and the results show that restricted access measures taken collaboratively by stations produce less delay and faster evacuation. Finally, a sensitivity analysis is conducted, from which we find that the departure interval and maximum conveying capacity of the train affect passenger delay markedly in the process of passenger control and infer that control measures should be taken at stations near to the one experiencing an emergency.

  8. Space Station Freedom (SSF) Data Management System (DMS) performance model data base

    Science.gov (United States)

    Stovall, John R.

    1993-01-01

    The purpose of this document was originally to be a working document summarizing Space Station Freedom (SSF) Data Management System (DMS) hardware and software design, configuration, performance and estimated loading data from a myriad of source documents such that the parameters provided could be used to build a dynamic performance model of the DMS. The document is published at this time as a close-out of the DMS performance modeling effort resulting from the Clinton Administration mandated Space Station Redesign. The DMS as documented in this report is no longer a part of the redesigned Space Station. The performance modeling effort was a joint undertaking between the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Flight Data Systems Division (FDSD) and the NASA Ames Research Center (ARC) Spacecraft Data Systems Research Branch. The scope of this document is limited to the DMS core network through the Man Tended Configuration (MTC) as it existed prior to the 1993 Clinton Administration mandated Space Station Redesign. Data is provided for the Standard Data Processors (SDP's), Multiplexer/Demultiplexers (MDM's) and Mass Storage Units (MSU's). Planned future releases would have added the additional hardware and software descriptions needed to describe the complete DMS. Performance and loading data through the Permanent Manned Configuration (PMC) was to have been included as it became available. No future releases of this document are presently planned pending completion of the present Space Station Redesign activities and task reassessment.

  9. Lithium-ion battery aging mechanisms and life model under different charging stresses

    Science.gov (United States)

    Gao, Yang; Jiang, Jiuchun; Zhang, Caiping; Zhang, Weige; Ma, Zeyu; Jiang, Yan

    2017-07-01

    The charging time-consuming and lifespan of lithium-ion batteries have always been the bottleneck for the tremendous application of electric vehicles. In this paper, cycle life tests are conducted to reveal the influence of different charging current rates and cut-off voltages on the aging mechanism of batteries. The long-term effects of charging current rates and cut-off voltages on capacity degradation and resistance increase are compared. The results show that there exists a critical charging current and a critical charging cut-off voltage. When the charging stress exceeds the critical value, battery degradation speed will be greatly accelerated. Furthermore, battery aging mechanisms at various charging currents and cut-off voltages are investigated using incremental capacity analysis. It is indicated that charging current and cut-off voltage should be reduced to retard battery degradation when the battery degrades to a certain extent. The time when the loss of electrode material accelerates is taken as the crisis to reduce charging current and the time when the loss of lithium inventory accelerates is taken as the crisis to reduce charging cut-off voltage. Moreover, an experiential model quantitatively describing the relationship between capacity degradation rate and charging stresses at different aging states is established.

  10. Modeling Passengers’ Boarding Behavior at the Platform of High Speed Railway Station

    Directory of Open Access Journals (Sweden)

    Tie-Qiao Tang

    2017-01-01

    Full Text Available Modeling passengers’ motion at high speed railway (HSR station has been a hot topic in the field of pedestrian flow theory. However, little effort has been made to explore the passengers’ boarding behaviors at the platform of HSR station. This study proposes a cellular automaton (CA model to study the passengers’ boarding behavior at the platform of HSR station. Some numerical tests are conducted to explore the passengers’ movements and the complex traffic phenomena (e.g., each passenger’s trajectory, congestion, and travel time which occur during the boarding process. The numerical results illustrate that the passengers’ inflow rate and entrance choice behavior have significant impacts on the boarding efficiency. These results can help managers to understand the passengers’ boarding behavior and to improve the boarding efficiency.

  11. An Integrated Data Analysis model to determine ion effective charge from beam attenuation and charge exchange emission measurements

    Science.gov (United States)

    Nornberg, M. D.; den Hartog, D. J.; Reusch, L. M.

    2017-10-01

    We have created a forward model for charge-exchange impurity density measurements that incorporates neutral beam attenuation measurements self-consistently for determining the ion effective charge Zeff in MST PPCD plasmas. Detailed knowledge of Zeff is critical to determining the resistive dissipation of hot plasmas and requires knowledge of the impurity content and dynamics. Previously, Zeff profiles were determined from soft-x-ray brightness measurements by using charge-exchange impurity density measurements as prior information using an Integrated Data Analysis (IDA) method. The model is extended to include a self-consistent calculation of the neutral beam attenuation and includes measurements of the beam Doppler-shift spectrum and shine-through particle flux. Methods of experimental design are employed to calculate the information gained from different diagnostic combinations. The analysis shows that while attenuation measurements alone do not provide a unique impurity density measurement in the case of a multi-species inhomogeneous plasmas, they do provide a valuable measurement of the Zeff profile and constrain the range of contributing impurity densities. Supported by US DOE.

  12. Mass and charge conservation check in dynamic models: application to the new ADM1 model.

    Science.gov (United States)

    de Gracia, M; Sancho, L; García-Heras, J L; Vanrolleghem, P; Ayesa, E

    2006-01-01

    This paper proposes a systematic methodology for the analysis of the mass and charge balances in dynamic models expressed using the Petersen matrix notation. This methodology is based on the definition of the model components via elemental mass fractions and in the estimation of the COD as a function of the redox equations associated with these elements. This approach makes the automatic calculation of all the stoichiometric coefficients under different measuring units and the study of COD, charge or mass fluxes easier. As an example of its application this methodology was applied to the ADM1 in order to illustrate its usefulness for the analysis of organic matter characterisation, nitrogen release or biogas composition in anaerobic digestion. The application of the methodology for a rigorous integration of different IWA models is proposed for further study.

  13. Multipole correction of atomic monopole models of molecular charge distribution. I. Peptides

    Science.gov (United States)

    Sokalski, W. A.; Keller, D. A.; Ornstein, R. L.; Rein, R.

    1993-01-01

    The defects in atomic monopole models of molecular charge distribution have been analyzed for several model-blocked peptides and compared with accurate quantum chemical values. The results indicate that the angular characteristics of the molecular electrostatic potential around functional groups capable of forming hydrogen bonds can be considerably distorted within various models relying upon isotropic atomic charges only. It is shown that these defects can be corrected by augmenting the atomic point charge models by cumulative atomic multipole moments (CAMMs). Alternatively, sets of off-center atomic point charges could be automatically derived from respective multipoles, providing approximately equivalent corrections. For the first time, correlated atomic multipoles have been calculated for N-acetyl, N'-methylamide-blocked derivatives of glycine, alanine, cysteine, threonine, leucine, lysine, and serine using the MP2 method. The role of the correlation effects in the peptide molecular charge distribution are discussed.

  14. INTELLECTUAL MODEL FORMATION OF RAILWAY STATION WORK DURING THE TRAIN OPERATION EXECUTION

    Directory of Open Access Journals (Sweden)

    O. V. Lavrukhin

    2014-11-01

    Full Text Available Purpose. The aim of this research work is to develop an intelligent technology for determination of the optimal route of freight trains administration on the basis of the technical and technological parameters. This will allow receiving the operational informed decisions by the station duty officer regarding to the train operation execution within the railway station. Metodology. The main elements of the research are the technical and technological parameters of the train station during the train operation. The methods of neural networks in order to form the self-teaching automated system were put in the basis of the generated model of train operation execution. Findings. The presented model of train operation execution at the railway station is realized on the basis of artificial neural networks using learning algorithm with a «teacher» in Matlab environment. The Matlab is also used for the immediate implementation of the intelligent automated control system of the train operation designed for the integration into the automated workplace of the duty station officer. The developed system is also useful to integrate on workplace of the traffic controller. This proposal is viable in case of the availability of centralized traffic control on the separate section of railway track. Originality. The model of train station operation during the train operation execution with elements of artificial intelligence was formed. It allows providing informed decisions to the station duty officer concerning a choice of rational and a safe option of reception and non-stop run of the trains with the ability of self-learning and adaptation to changing conditions. This condition is achieved by the principles of the neural network functioning. Practical value. The model of the intelligent system management of the process control for determining the optimal route receptionfor different categories of trains was formed.In the operational mode it offers the possibility

  15. Estimating spares requirements for Space Station Freedom using the M-SPARE model

    Science.gov (United States)

    Kline, Robert C.; Sherbrooke, Craig C.

    1992-08-01

    The Logistics Management Institute developed a methodology that estimates the optimal orbital replaceable unit (ORU) spares inventory for NASA's Space Station Freedom. NASA is using this methodology to select a spares inventory that will maximize station availability, i.e., the probability that no critical system is inoperative for lack of an ORU spare over the resupply cycle. It is based upon a marginal analysis approach. Spares are ranked in order of decreasing benefit per cost (the improvement provided to station availability per dollar) and added, in that order, to the inventory until a target resource expenditure or availability is reached. The methodology also develops optimal spares inventories constrained by the spares weight the shuttle can carry, the spares volume the station can store, or a combination of resources. To implement our methodology, we developed the Multiple Spares Prioritization and Availability to Resource Evaluation (M-SPARE) model that operates on a personal computer. M-SPARE presents the maximum availability for an entire range of resource expenditures. The model also converts annual spares requirements over any period of the station's life into funding estimates for the next 9 years. In this guide, we describe the M-SPARE methodology, operation, and analytical capabilities.

  16. Indirect adaptive soft computing based wavelet-embedded control paradigms for WT/PV/SOFC in a grid/charging station connected hybrid power system.

    Science.gov (United States)

    Mumtaz, Sidra; Khan, Laiq; Ahmed, Saghir; Bader, Rabiah

    2017-01-01

    This paper focuses on the indirect adaptive tracking control of renewable energy sources in a grid-connected hybrid power system. The renewable energy systems have low efficiency and intermittent nature due to unpredictable meteorological conditions. The domestic load and the conventional charging stations behave in an uncertain manner. To operate the renewable energy sources efficiently for harvesting maximum power, instantaneous nonlinear dynamics should be captured online. A Chebyshev-wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking) control paradigm is proposed for variable speed wind turbine-permanent synchronous generator (VSWT-PMSG). A Hermite-wavelet incorporated NeuroFuzzy indirect adaptive MPPT control strategy for photovoltaic (PV) system to extract maximum power and indirect adaptive tracking control scheme for Solid Oxide Fuel Cell (SOFC) is developed. A comprehensive simulation test-bed for a grid-connected hybrid power system is developed in Matlab/Simulink. The robustness of the suggested indirect adaptive control paradigms are evaluated through simulation results in a grid-connected hybrid power system test-bed by comparison with conventional and intelligent control techniques. The simulation results validate the effectiveness of the proposed control paradigms.

  17. Modeling Transport in Ultrathin Si Nanowires: Charged versus Neutral Impurities

    DEFF Research Database (Denmark)

    Rurali, Riccardo; Markussen, Troels; Suné, Jordi

    2008-01-01

    Abstract: At room temperature dopants in semiconducting nanowires are ionized. We show that the long-range electrostatic potential due to charged dopants has a dramatic impact on the transport properties in ultrathin wires and can virtually block minority carriers. Our quantitative estimates of t...

  18. Optimization of hydrogen stations in Florida using the Flow-Refueling Location Model

    Energy Technology Data Exchange (ETDEWEB)

    Kuby, Michael; Kim, Jong-Geun [School of Geographical Sciences, Arizona State University, Tempe, AZ 85287-5302 (United States); Lines, Lee [Department of Environmental Studies, Rollins College, 1000 Holt Ave., Box 2753, Winter Park, FL 32789-4499 (United States); Schultz, Ronald; Xie, Zhixiao [Department of Geosciences, Florida Atlantic University, Boca Raton, FL 33431 (United States); Lim, Seow [Salt River Project, 1521 N. Project Drive, Tempe, AZ 85281-1298 (United States)

    2009-08-15

    This paper develops and applies a model that locates hydrogen stations to refuel the maximum volume of vehicle flows. Inputs to the model include a road network with average speeds; the origin-destination flow volumes between each origin and destination; a maximum driving range between refueling stops; and the number of stations to build. The Flow-Refueling Location Model maximizes the flow volumes that can be refueled, measured either in number of trips or vehicle-miles traveled. Geographic Information Systems and heuristic algorithms are integrated in a spatial decision support system that researchers can use to develop data, enter assumptions, analyze scenarios, evaluate tradeoffs, and map results. For the Florida Hydrogen Initiative, we used this model to investigate strategies for rolling out an initial refueling infrastructure in Florida at two different scales of analysis: metropolitan Orlando and statewide. By analyzing a variety of scenarios at both scales of analysis, we identify a robust set of stations that perform well under a variety of assumptions, and develop a strategy for phasing in clustered and connecting stations in several stages or tiers. (author)

  19. What input data are needed to accurately model electromagnetic fields from mobile phone base stations?

    NARCIS (Netherlands)

    Beekhuizen, Johan; Kromhout, Hans; Bürgi, Alfred; Huss, Anke; Vermeulen, Roel

    The increase in mobile communication technology has led to concern about potential health effects of radio frequency electromagnetic fields (RF-EMFs) from mobile phone base stations. Different RF-EMF prediction models have been applied to assess population exposure to RF-EMF. Our study examines what

  20. Cumulative atomic multipole moments complement any atomic charge model to obtain more accurate electrostatic properties

    Science.gov (United States)

    Sokalski, W. A.; Shibata, M.; Ornstein, R. L.; Rein, R.

    1992-01-01

    The quality of several atomic charge models based on different definitions has been analyzed using cumulative atomic multipole moments (CAMM). This formalism can generate higher atomic moments starting from any atomic charges, while preserving the corresponding molecular moments. The atomic charge contribution to the higher molecular moments, as well as to the electrostatic potentials, has been examined for CO and HCN molecules at several different levels of theory. The results clearly show that the electrostatic potential obtained from CAMM expansion is convergent up to R-5 term for all atomic charge models used. This illustrates that higher atomic moments can be used to supplement any atomic charge model to obtain more accurate description of electrostatic properties.

  1. The European fossil-fuelled power station database used in the SEI CASM model

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, P. [comp.] [Stockholm Environment Inst. at York (United Kingdom)

    1996-06-01

    The database contains details of power stations in Europe that burn fossil-fuels. All countries are covered from Ireland to the European region of Russia as far as the Urals. The following data are given for each station: Location (country and EMEP square), capacity (net MW{sub e} and boiler size), year of commissioning, and fuels burnt. A listing of the database is included in the report. The database is primarily used for estimation of emissions and abatement costs of sulfur and nitrogen oxides in the SEI acid rain model CASM. 24 refs, tabs

  2. Analytical estimation of effective charges at saturation in Poisson-Boltzmann cell models

    CERN Document Server

    Trizac, E; Bocquet, L

    2003-01-01

    We propose a simple approximation scheme for computing the effective charges of highly charged colloids (spherical or cylindrical with infinite length). Within non-linear Poisson-Boltzmann theory, we start from an expression for the effective charge in the infinite-dilution limit which is asymptotically valid for large salt concentrations; this result is then extended to finite colloidal concentration, approximating the salt partitioning effect which relates the salt content in the suspension to that of a dialysing reservoir. This leads to an analytical expression for the effective charge as a function of colloid volume fraction and salt concentration. These results compare favourably with the effective charges at saturation (i.e. in the limit of large bare charge) computed numerically following the standard prescription proposed by Alexander et al within the cell model.

  3. Polyhedral charge-packing model for blood pH changes in disease ...

    African Journals Online (AJOL)

    Administrator

    2007-05-02

    May 2, 2007 ... Full Length Research Paper. Polyhedral charge-packing model for blood pH changes in disease states .... (the structure of diamond), the octahedron. This explains the high resistance to change (buffering) of both .... The understanding of the polyhedral charge-packing phenomenon in disease states pHs,.

  4. Near-Field Characterization of Methane Emission Variability from a Compressor Station Using a Model Aircraft.

    Science.gov (United States)

    Nathan, Brian J; Golston, Levi M; O'Brien, Anthony S; Ross, Kevin; Harrison, William A; Tao, Lei; Lary, David J; Johnson, Derek R; Covington, April N; Clark, Nigel N; Zondlo, Mark A

    2015-07-07

    A model aircraft equipped with a custom laser-based, open-path methane sensor was deployed around a natural gas compressor station to quantify the methane leak rate and its variability at a compressor station in the Barnett Shale. The open-path, laser-based sensor provides fast (10 Hz) and precise (0.1 ppmv) measurements of methane in a compact package while the remote control aircraft provides nimble and safe operation around a local source. Emission rates were measured from 22 flights over a one-week period. Mean emission rates of 14 ± 8 g CH4 s(-1) (7.4 ± 4.2 g CH4 s(-1) median) from the station were observed or approximately 0.02% of the station throughput. Significant variability in emission rates (0.3-73 g CH4 s(-1) range) was observed on time scales of hours to days, and plumes showed high spatial variability in the horizontal and vertical dimensions. Given the high spatiotemporal variability of emissions, individual measurements taken over short durations and from ground-based platforms should be used with caution when examining compressor station emissions. More generally, our results demonstrate the unique advantages and challenges of platforms like small unmanned aerial vehicles for quantifying local emission sources to the atmosphere.

  5. Anisotropic charged physical models with generalized polytropic equation of state

    Science.gov (United States)

    Nasim, A.; Azam, M.

    2018-01-01

    In this paper, we found the exact solutions of Einstein-Maxwell equations with generalized polytropic equation of state (GPEoS). For this, we consider spherically symmetric object with charged anisotropic matter distribution. We rewrite the field equations into simple form through transformation introduced by Durgapal (Phys Rev D 27:328, 1983) and solve these equations analytically. For the physically acceptability of these solutions, we plot physical quantities like energy density, anisotropy, speed of sound, tangential and radial pressure. We found that all solutions fulfill the required physical conditions. It is concluded that all our results are reduced to the case of anisotropic charged matter distribution with linear, quadratic as well as polytropic equation of state.

  6. Dynamics of Charged Particulate Systems Modeling, Theory and Computation

    CERN Document Server

    Zohdi, Tarek I

    2012-01-01

    The objective of this monograph is to provide a concise introduction to the dynamics of systems comprised of charged small-scale particles. Flowing, small-scale, particles ("particulates'') are ubiquitous in industrial processes and in the natural sciences. Applications include electrostatic copiers, inkjet printers, powder coating machines, etc., and a variety of manufacturing processes. Due to their small-scale size, external electromagnetic fields can be utilized to manipulate and control charged particulates in industrial processes in order to achieve results that are not possible by purely mechanical means alone. A unique feature of small-scale particulate flows is that they exhibit a strong sensitivity to interparticle near-field forces, leading to nonstandard particulate dynamics, agglomeration and cluster formation, which can strongly affect manufactured product quality. This monograph also provides an introduction to the mathematically-related topic of the dynamics of swarms of interacting objects, ...

  7. Modulational instability of charge transport in the Peyrard-Bishop-Holstein model

    Energy Technology Data Exchange (ETDEWEB)

    Tabi, Conrad Bertrand; Mohamadou, Alidou; Kofane, Timoleon Crepin, E-mail: contab408@hotmail.co, E-mail: mohdoufr@yahoo.f, E-mail: tckofane@yahoo.co [Laboratory of Mechanics, Department of Physics, Faculty of Science, University of Yaounde I, PO Box 812, Yaounde (Cameroon)

    2009-08-19

    We report on modulational instability (MI) on a DNA charge transfer model known as the Peyrard-Bishop-Holstein (PBH) model. In the continuum approximation, the system reduces to a modified Klein-Gordon-Schroedinger (mKGS) system through which linear stability analysis is performed. This model shows some possibilities for the MI region and the study is carried out for some values of the nearest-neighbor transfer integral. Numerical simulations are then performed, which confirm analytical predictions and give rise to localized structure formation. We show how the spreading of charge deeply depends on the value of the charge-lattice-vibrational coupling.

  8. On the Analytical Model of Charge Evolution of Solar Flare Ions

    Science.gov (United States)

    Perez-Peraza, Jorge; Balderas-Avilez, Gabriel; Rodriguez-Frias, Dolores; Del Peral, Luis; Hebrero, Gema; Cruz, Ricardo

    Models attempting to describe the charge state of solar flare ions are in general of numerical nature, where the involved physics is masked by their high mathematical complexity. There is however, the oldest of the models, developed long ago for one of us, which is of analytical nature, and based in very simple physical concepts, namely hereafter the High Energy Crosssections Model (HECSM). In this model definition of the charge state of the energetic ions occurs during the acceleration process at the flare source. It is assumed the atomic interactions between a population which is being accelerated getting an exponential (or power law) spectrum, namely the ions projectiles, and another population which is in thermodynamic equilibrium (TE), with a Maxwellian spectrum, namely the targets. In contrast with other models that use thermal cross-sections (ionization and recombination) even for energetic ions which are out of the (TE), in our model we employ High Energy Cross-sections for electron capture and loss, since the population which is being accelerated acquires a non-thermal spectrum. First, we have built temperature-dependent cross-sections. Then, we have developed criteria for charge interchange establishment, it is determined whether there is establishment of (1) both processes, capture and los, or (2) only one of them, or even (3) none of them. In case (1) charge equilibrium is reached. In case (2) when only electron capture is established, at the beginning of the acceleration process, the local charge value will decrease up to an energy where both crosssection becomes of the same order, or when only electron loss is established the effective charge goes faster toward the nuclear charge value than in conditions of charge equilibrium. In case (3) ions keep the local thermal charge at the source temperature. After, we derivate an analytical expression for the Effective Charge (equilibrium charge), qef f, on basis to direct and simple physical concepts. We

  9. Surface Complexation Modeling in Variable Charge Soils: Charge Characterization by Potentiometric Titration

    Directory of Open Access Journals (Sweden)

    Giuliano Marchi

    2015-10-01

    Full Text Available ABSTRACT Intrinsic equilibrium constants of 17 representative Brazilian Oxisols were estimated from potentiometric titration measuring the adsorption of H+ and OH− on amphoteric surfaces in suspensions of varying ionic strength. Equilibrium constants were fitted to two surface complexation models: diffuse layer and constant capacitance. The former was fitted by calculating total site concentration from curve fitting estimates and pH-extrapolation of the intrinsic equilibrium constants to the PZNPC (hand calculation, considering one and two reactive sites, and by the FITEQL software. The latter was fitted only by FITEQL, with one reactive site. Soil chemical and physical properties were correlated to the intrinsic equilibrium constants. Both surface complexation models satisfactorily fit our experimental data, but for results at low ionic strength, optimization did not converge in FITEQL. Data were incorporated in Visual MINTEQ and they provide a modeling system that can predict protonation-dissociation reactions in the soil surface under changing environmental conditions.

  10. An attempt for modeling the atmospheric transport of 3H around Kakrapar Atomic Power Station.

    Science.gov (United States)

    Patra, A K; Nankar, D P; Joshi, C P; Venkataraman, S; Sundar, D; Hegde, A G

    2008-01-01

    Prediction of downwind tritium air concentrations in the environment around Kakrapar Atomic Power Station (KAPS) was studied on the basis of Gaussian plume dispersion model. The tritium air concentration by field measurement [measured tritium air concentrations in the areas adjacent to KAPS] were compared with the theoretically calculated values (predicted) to validate the model. This approach will be useful in evaluating environmental radiological impacts due to pressurised heavy water reactors.

  11. Simulation Model of Logistic Support to Isolated Airspace Smveillance Radar Stations

    Directory of Open Access Journals (Sweden)

    Tomislav Crnković

    2008-03-01

    Full Text Available A simulation model of the radar network operation of fivemilitary radar stations has been developed. Simulation waspeiformed in GPSS language and contains the time of operationof five radars through a period of one year, time of plannedpreventive maintenance, irregularities, time of corrective maintenanceand maintenance team(s. The simulation shows theinfluence of the number of maintenance teams on the availabilityof each radar and presents a good orienteering point fordefining the optimal model of preventive and corrective maintenanceof the radar network.

  12. Modelling indoor electromagnetic fields (EMF) from mobile phone base stations for epidemiological studies.

    Science.gov (United States)

    Beekhuizen, J; Vermeulen, R; van Eijsden, M; van Strien, R; Bürgi, A; Loomans, E; Guxens, M; Kromhout, H; Huss, A

    2014-06-01

    Radio frequency electromagnetic fields (RF-EMF) from mobile phone base stations can be reliably modelled for outdoor locations, using 3D radio wave propagation models that consider antenna characteristics and building geometry. For exposure assessment in epidemiological studies, however, it is especially important to determine indoor exposure levels as people spend most of their time indoors. We assessed the accuracy of indoor RF-EMF model predictions, and whether information on building characteristics could increase model accuracy. We performed 15-minute spot measurements in 263 rooms in 101 primary schools and 30 private homes in Amsterdam, the Netherlands. At each measurement location, we collected information on building characteristics that can affect indoor exposure to RF-EMF, namely glazing and wall and window frame materials. Next, we modelled RF-EMF at the measurement locations with the 3D radio wave propagation model NISMap. We compared model predictions with measured values to evaluate model performance, and explored if building characteristics modified the association between modelled and measured RF-EMF using a mixed effect model. We found a Spearman correlation of 0.73 between modelled and measured total downlink RF-EMF from base stations. The average modelled and measured RF-EMF were 0.053 and 0.041mW/m(2), respectively, and the precision (standard deviation of the differences between predicted and measured values) was 0.184mW/m(2). Incorporating information on building characteristics did not improve model predictions. Although there is exposure misclassification, we conclude that it is feasible to reliably rank indoor RF-EMF from mobile phone base stations for epidemiological studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Model of traffic access mode and railway station choice of suburban railway system in Slovenia

    Directory of Open Access Journals (Sweden)

    Gregor RAK

    2014-12-01

    Full Text Available This article presents the establishment of a model of understanding the access mode and railway station choice of Slovenian passengers. Therefore, a model has been designed to predict the determination of existing decision making preferences of railway users about the access mode and railway station choice with a stated preference survey and face to face method. The target group in the survey were railway passengers in the suburban environment that use the rail for work and school purposes. The total number of respondents was 412. The survey showed that most passengers access the railway station with car (60,2%, by foot (26,2%, with public transport (bus – 8,3% and with bike (5,3%. Average distance to the station is 4,9 km, average time of access is 10,5 min. Upon exit most passengers walk to the final destination (84,5%, use the public transport (bus – 14,1%, car (1,2% or bike (0,2%. Average time from exit of the train to final destination is 13,1 min, average distance is 1,58 km.

  14. Application of a Cloud Model-Set Pair Analysis in Hazard Assessment for Biomass Gasification Stations.

    Science.gov (United States)

    Yan, Fang; Xu, Kaili

    2017-01-01

    Because a biomass gasification station includes various hazard factors, hazard assessment is needed and significant. In this article, the cloud model (CM) is employed to improve set pair analysis (SPA), and a novel hazard assessment method for a biomass gasification station is proposed based on the cloud model-set pair analysis (CM-SPA). In this method, cloud weight is proposed to be the weight of index. In contrast to the index weight of other methods, cloud weight is shown by cloud descriptors; hence, the randomness and fuzziness of cloud weight will make it effective to reflect the linguistic variables of experts. Then, the cloud connection degree (CCD) is proposed to replace the connection degree (CD); the calculation algorithm of CCD is also worked out. By utilizing the CCD, the hazard assessment results are shown by some normal clouds, and the normal clouds are reflected by cloud descriptors; meanwhile, the hazard grade is confirmed by analyzing the cloud descriptors. After that, two biomass gasification stations undergo hazard assessment via CM-SPA and AHP based SPA, respectively. The comparison of assessment results illustrates that the CM-SPA is suitable and effective for the hazard assessment of a biomass gasification station and that CM-SPA will make the assessment results more reasonable and scientific.

  15. Optimal Day-ahead Charging Scheduling of Electric Vehicles through an Aggregative Game Model

    DEFF Research Database (Denmark)

    Liu, Zhaoxi; Wu, Qiuwei; Huang, Shaojun

    2017-01-01

    in a grid, it will impact spot prices in the electricity market and consequently influence the charging scheduling itself. The interaction between the spot prices and the EV demand needs to be considered in the EV charging scheduling, otherwise it will lead to a higher charging cost. A day-ahead EV charging...... scheduling based on an aggregative game model is proposed in this paper. The impacts of the EV demand on the electricity prices are formulated with the game model in the scheduling considering possible actions of other EVs. The existence and uniqueness of the pure strategy Nash equilibrium are proved...... with the proposed game model were carried out using real world driving data from the Danish National Travel Surveys. The impacts of the EV driving patterns and price forecasts on the EV demand with the proposed game model were also analysed....

  16. Charge while driving” for electric vehicles: road traffic modeling and energy assessment

    National Research Council Canada - National Science Library

    DEFLORIO, Francesco Paolo; CASTELLO, Luca; PINNA, Ivano; GUGLIELMI, Paolo

    2015-01-01

    ...) electric vehicles, from both traffic and energy points of view. To accurately quantify the electric power required from an energy supplier for the proper management of the charging system, a traffic simulation model is implemented...

  17. Charged-current inclusive neutrino cross sections in the SuperScaling model

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, M. V., E-mail: martin.inrne@gmail.com [Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Sofia 1784 (Bulgaria); Grupo de Física Nuclear, Departamento de Física Atómica, Molecular y Nuclear, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, Madrid E-28040 (Spain); Megias, G. D.; Caballero, J. A. [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Sevilla, 41080 Sevilla (Spain); González-Jiménez, R. [Department of Physics and Astronomy, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium); Moreno, O.; Donnelly, T. W. [Center for Theoretical Physics, Laboratory for Nuclear Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Barbaro, M. B. [Dipartimento di Fisica, Università di Torino and INFN, Sezione di Torino, Via P. Giuria 1, 10125 Torino (Italy); Antonov, A. N. [Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Sofia 1784 (Bulgaria); Moya de Guerra, E.; Udías, J. M. [Grupo de Física Nuclear, Departamento de Física Atómica, Molecular y Nuclear, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, Madrid E-28040 (Spain)

    2016-03-25

    SuperScaling model (SuSA) predictions to neutrino-induced charged-current π{sup +} production in the Δ-resonance region are explored under MiniBooNE experimental conditions. The SuSA charged-current π{sup +} results are in good agreement with data on neutrino flux-averaged double-differential cross sections. The SuSA model for quasielastic scattering and its extension to the pion production region are used for predictions of charged-current inclusive neutrino-nucleus cross sections. Results are also compared with the T2K experimental data for inclusive scattering.

  18. Doping driven metal-insulator transitions and charge orderings in the extended Hubbard model

    CERN Document Server

    Kapcia, K J; Capone, M; Amaricci, A

    2016-01-01

    We perform a thorough study of an extended Hubbard model featuring local and nearest-neighbor Coulomb repulsion. Using dynamical mean-field theory we investigated the zero temperature phase-diagram of this model as a function of the chemical doping. The interplay between local and non-local interaction drives a variety of phase-transitions connecting two distinct charge-ordered insulators, i.e., half-filled and quarter-filled, a charge-ordered metal and a Mott insulating phase. We characterize these transitions and the relative stability of the solutions and we show that the two interactions conspire to stabilize the quarter-filled charge ordered phase.

  19. Physical constants and invariant charges of the U(1) x SU(3) model

    Energy Technology Data Exchange (ETDEWEB)

    Efremov, A.V.; Ivanov, S.V.; Nesterenko, V.A.

    1981-11-01

    We have investigated the form of the invariant charges in a unified model of the strong and electromagnetic interactions. We have considered the asymptotic properties of the interaction constants in the Higgs sector. We conclude that the dependence of the invariant charges on Vertical Barq/sup 2/Vertical Bar does not contradict the constraints which are imposed on the parameters of the model by experimental tests of QED.

  20. Long-Range Charge Order in the Extended Holstein-Hubbard Model

    Science.gov (United States)

    Miyao, Tadahiro

    2016-10-01

    This study investigated the extended Holstein-Hubbard model at half-filling as a model for describing the interplay of electron-electron and electron-phonon couplings. When the electron-phonon and nearest-neighbor electron-electron interactions are strong, we prove the existence of long-range charge order in three or more dimensions at a sufficiently low temperature. As a result, we rigorously justify the phase competition between the antiferromagnetism and charge orders.

  1. Ligand and Charge Distribution (LCD) model for the description of fulvic acid adsorption to goethite

    NARCIS (Netherlands)

    Weng, L.P.; Riemsdijk, van W.H.; Koopal, L.K.; Hiemstra, T.

    2006-01-01

    The LCD model (Ligand and Charge Distribution) has recently been proposed to describe the adsorption of humic substances to oxides, in which the CD-MUSIC model and the NICA model for ion binding to respectively oxides and humic substances are integrated. In this paper, the LCD model is improved by

  2. Quasi-integrability in deformed sine-Gordon models and infinite towers of conserved charges

    Science.gov (United States)

    Blas, Harold; Callisaya, Hector Flores

    2018-02-01

    We have studied the space-reflection symmetries of some soliton solutions of deformed sine-Gordon models in the context of the quasi-integrability concept. Considering a dual pair of anomalous Lax representations of the deformed model we compute analytically and numerically an infinite number of alternating conserved and asymptotically conserved charges through a modification of the usual techniques of integrable field theories. The charges associated to two-solitons with a definite parity under space-reflection symmetry, i.e. kink-kink (odd parity) and kink-antikink (even parity) scatterings with equal and opposite velocities, split into two infinite towers of conserved and asymptotically conserved charges. For two-solitons without definite parity under space-reflection symmetry (kink-kink and kink-antikink scatterings with unequal and opposite velocities) our numerical results show the existence of the asymptotically conserved charges only. However, we show that in the center-of-mass reference frame of the two solitons the parity symmetries and their associated set of exactly conserved charges can be restored. Moreover, the positive parity breather-like (kink-antikink bound state) solution exhibits a tower of exactly conserved charges and a subset of charges which are periodic in time. We back up our results with extensive numerical simulations which also demonstrate the existence of long lived breather-like states in these models. The time evolution has been simulated by the 4th order Runge-Kutta method supplied with non-reflecting boundary conditions.

  3. Application of the hydrodynamic predictive modeling on the example of the pumping station 'Bezdan 1'

    Directory of Open Access Journals (Sweden)

    Polomčić Dušan M.

    2014-01-01

    Full Text Available In the area of Bezdan, the construction of a new pumping station, p.s. 'Bezdan 1', on the location of the existing and nonfunctional pumping station 'Bezdan I', is envisaged. Given the position of the future pump station, a problem of digging the foundation pits in terms of protection from high groundwater levels, was noticed. This paper aims to analyze the possibilities for lowering the groundwater levels below the projected elevation, which will enable unobstructed work on the pumping station. By using the hydrodynamic analysis and its most complex and most applicable methods of three-dimensional hydrodynamic modeling of aquifer regime, based on the numerical method of finite differences, the system of protection and variations of the protection solutions from groundwater at the research location of the future p.s. 'Bezdan 1' was defined. Three variants of solution were given, and characteristics of the system of protection from groundwater were defined for each, the optimal number of drainage wells in the system and their spatial distribution and the time required for maximal effects of the lowering of the groundwater levels below the elevation of the excavation facilities of CS 'Bezdan 1'. Presented paper provides the basis for some of the methods of multicriteria optimization and the selection of the optimal variant of the system of protection from groundwater's, considering, in this way, the weight of various factors that influence the choice of the variant, such as technical, economic, environmental and safety factors.

  4. Evaluation of Maximum Radionuclide Groundwater Concentrations for Basement Fill Model. Zion Station Restoration Project

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, T. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-05-20

    ZionSolutions is in the process of decommissioning the Zion Nuclear Power Station (ZNPS). After decommissioning is completed, the site will contain two reactor Containment Buildings, the Fuel Handling Building and Transfer Canals, Auxiliary Building, Turbine Building, Crib House/Forebay, and a Waste Water Treatment Facility that have been demolished to a depth of 3 feet below grade. Additional below ground structures remaining will include the Main Steam Tunnels and large diameter intake and discharge pipes. These additional structures are not included in the modeling described in this report, but the inventory remaining (expected to be very low) will be included with one of the structures that are modeled as designated in the Zion Station Restoration Project (ZSRP) License Termination Plan (LTP). The remaining underground structures will be backfilled with clean material. The final selection of fill material has not been made.

  5. Global cross-station assessment of neuro-fuzzy models for estimating daily reference evapotranspiration

    Science.gov (United States)

    Shiri, Jalal; Nazemi, Amir Hossein; Sadraddini, Ali Ashraf; Landeras, Gorka; Kisi, Ozgur; Fard, Ahmad Fakheri; Marti, Pau

    2013-02-01

    SummaryAccurate estimation of reference evapotranspiration is important for irrigation scheduling, water resources management and planning and other agricultural water management issues. In the present paper, the capabilities of generalized neuro-fuzzy models were evaluated for estimating reference evapotranspiration using two separate sets of weather data from humid and non-humid regions of Spain and Iran. In this way, the data from some weather stations in the Basque Country and Valencia region (Spain) were used for training the neuro-fuzzy models [in humid and non-humid regions, respectively] and subsequently, the data from these regions were pooled to evaluate the generalization capability of a general neuro-fuzzy model in humid and non-humid regions. The developed models were tested in stations of Iran, located in humid and non-humid regions. The obtained results showed the capabilities of generalized neuro-fuzzy model in estimating reference evapotranspiration in different climatic zones. Global GNF models calibrated using both non-humid and humid data were found to successfully estimate ET0 in both non-humid and humid regions of Iran (the lowest MAE values are about 0.23 mm for non-humid Iranian regions and 0.12 mm for humid regions). non-humid GNF models calibrated using non-humid data performed much better than the humid GNF models calibrated using humid data in non-humid region while the humid GNF model gave better estimates in humid region.

  6. Unconventional spin-charge phase separation in a model 2D cuprate

    Science.gov (United States)

    Panov, Yu. D.; Budrin, K. S.; Chikov, A. A.; Moskvin, A. S.

    2017-09-01

    In this Letter we address a challenging problem of a competition of charge and spin orders for high-Tc cuprates within a simplified 2D spin-pseudospin model which takes into account both conventional Heisenberg Cu2+-Cu2+ antiferromagnetic spin exchange coupling (J) and the on-site (U) and inter-site (V) charge correlations in the CuO2 planes with the on-site Hilbert space reduced to only three effective charge states (nominally Cu1+;2+;3+). We performed classical Monte-Carlo calculations for large square lattices implying the mobile doped charges and focusing on a case of a small inter-site repulsion V ≪ J. The on-site attraction (U 0) the homogeneous ground state antiferromagnetic solutions of the doped system found in a mean-field approximation are shown to be unstable with respect to a phase separation with the charge and spin subsystems behaving like immiscible quantum liquids. Puzzlingly, with lowering the temperature one can observe two sequential phase transitions: first, an antiferromagnetic ordering in the spin subsystem diluted by randomly distributed charges, then, a charge condensation in the charge droplets. The effects are illustrated by the Monte-Carlo calculations of the specific heat and longitudinal magnetic susceptibility.

  7. Modeling plug-in electric vehicle charging demand with BEAM: the framework for behavior energy autonomy mobility

    Energy Technology Data Exchange (ETDEWEB)

    Sheppard, Colin; Waraich, Rashid; Campbell, Andrew; Pozdnukov, Alexei; Gopal, Anand R.

    2017-05-01

    This report summarizes the BEAM modeling framework (Behavior, Energy, Mobility, and Autonomy) and its application to simulating plug-in electric vehicle (PEV) mobility, energy consumption, and spatiotemporal charging demand. BEAM is an agent-based model of PEV mobility and charging behavior designed as an extension to MATSim (the Multi-Agent Transportation Simulation model). We apply BEAM to the San Francisco Bay Area and conduct a preliminary calibration and validation of its prediction of charging load based on observed charging infrastructure utilization for the region in 2016. We then explore the impact of a variety of common modeling assumptions in the literature regarding charging infrastructure availability and driver behavior. We find that accurately reproducing observed charging patterns requires an explicit representation of spatially disaggregated charging infrastructure as well as a more nuanced model of the decision to charge that balances tradeoffs people make with regards to time, cost, convenience, and range anxiety.

  8. Simulation Model of Logistic Support to Isolated Airspace Smveillance Radar Stations

    OpenAIRE

    Tomislav Crnković; Ernest Bazijanac; Danko Basch

    2008-01-01

    A simulation model of the radar network operation of fivemilitary radar stations has been developed. Simulation waspeiformed in GPSS language and contains the time of operationof five radars through a period of one year, time of plannedpreventive maintenance, irregularities, time of corrective maintenanceand maintenance team(s). The simulation shows theinfluence of the number of maintenance teams on the availabilityof each radar and presents a good orienteering point fordefining the optimal m...

  9. Comparison of steel desulphurisation at homogenisation station with physical modelling results

    OpenAIRE

    L. Socha; Hudzieczek, Z.; Pilka, V.; Z. Piegza

    2015-01-01

    The paper deals with evaluation of relevant information about transfer processes taking place in the interface slag – metal and with the assessment of the rate and course of steel desulphurization. The study of mentioned processes took place with the verification of the results obtained by the plant experiments in the homogenization station using 180 t ladle and in the physical model of the ladle in the geometrical scale 1 : 9 supplemented by homogenization nozzle. Plant and physi...

  10. Building better water models using the shape of the charge distribution of a water molecule

    Science.gov (United States)

    Dharmawardhana, Chamila Chathuranga; Ichiye, Toshiko

    2017-11-01

    The unique properties of liquid water apparently arise from more than just the tetrahedral bond angle between the nuclei of a water molecule since simple three-site models of water are poor at mimicking these properties in computer simulations. Four- and five-site models add partial charges on dummy sites and are better at modeling these properties, which suggests that the shape of charge distribution is important. Since a multipole expansion of the electrostatic potential describes a charge distribution in an orthogonal basis set that is exact in the limit of infinite order, multipoles may be an even better way to model the charge distribution. In particular, molecular multipoles up to the octupole centered on the oxygen appear to describe the electrostatic potential from electronic structure calculations better than four- and five-site models, and molecular multipole models give better agreement with the temperature and pressure dependence of many liquid state properties of water while retaining the computational efficiency of three-site models. Here, the influence of the shape of the molecular charge distribution on liquid state properties is examined by correlating multipoles of non-polarizable water models with their liquid state properties in computer simulations. This will aid in the development of accurate water models for classical simulations as well as in determining the accuracy needed in quantum mechanical/molecular mechanical studies and ab initio molecular dynamics simulations of water. More fundamentally, this will lead to a greater understanding of how the charge distribution of a water molecule leads to the unique properties of liquid water. In particular, these studies indicate that p-orbital charge out of the molecular plane is important.

  11. Electrical charging effects on the sliding friction of a model nano-confined ionic liquid

    Energy Technology Data Exchange (ETDEWEB)

    Capozza, R.; Vanossi, A. [International School for Advanced Studies (SISSA), Via Bonomea 265, 34136 Trieste (Italy); CNR-IOM Democritos National Simulation Center, Via Bonomea 265, 34136 Trieste (Italy); Benassi, A. [CNR-IOM Democritos National Simulation Center, Via Bonomea 265, 34136 Trieste (Italy); Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, 01062 Dresden (Germany); Tosatti, E. [International School for Advanced Studies (SISSA), Via Bonomea 265, 34136 Trieste (Italy); CNR-IOM Democritos National Simulation Center, Via Bonomea 265, 34136 Trieste (Italy); International Centre for Theoretical Physics (ICTP), Strada Costiera 11, 34014 Trieste (Italy)

    2015-10-14

    Recent measurements suggest the possibility to exploit ionic liquids (ILs) as smart lubricants for nano-contacts, tuning their tribological and rheological properties by charging the sliding interfaces. Following our earlier theoretical study of charging effects on nanoscale confinement and squeezout of a model IL, we present here molecular dynamics simulations of the frictional and lubrication properties of that model under charging conditions. First, we describe the case when two equally charged plates slide while being held together to a confinement distance of a few molecular layers. The shear sliding stress is found to rise strongly and discontinuously as the number of IL layers decreases stepwise. However, the shear stress shows, within each given number of layers, only a weak dependence upon the precise value of the normal load, a result in agreement with data extracted from recent experiments. We subsequently describe the case of opposite charging of the sliding plates and follow the shear stress when the charging is slowly and adiabatically reversed in the course of time, under fixed load. Despite the fixed load, the number and structure of the confined IL layers change with changing charge, and that in turn drives strong friction variations. The latter involves first of all charging-induced freezing of the IL film, followed by a discharging-induced melting, both made possible by the nanoscale confinement. Another mechanism for charging-induced frictional changes is a shift of the plane of maximum shear from mid-film to the plate-film interface, and vice versa. While these occurrences and results invariably depend upon the parameters of the model IL and upon its specific interaction with the plates, the present study helps identifying a variety of possible behavior, obtained under very simple assumptions, while connecting it to an underlying equilibrium thermodynamics picture.

  12. Tuned and Balanced Redistributed Charge Scheme for Combined Quantum Mechanical and Molecular Mechanical (QM/MM) Methods and Fragment Methods: Tuning Based on the CM5 Charge Model.

    Science.gov (United States)

    Wang, Bo; Truhlar, Donald G

    2013-02-12

    Tuned and balanced redistributed charge schemes have been developed for modeling the electrostatic fields of bonds that are cut by a quantum mechanical-molecular mechanical boundary in combined quantum mechanical and molecular mechanical (QM/MM) methods. First, the charge is balanced by adjusting the charge on the MM boundary atom to conserve the total charge of the entire QM/MM system. In the balanced smeared redistributed charge (BSRC) scheme, the adjusted MM boundary charge is smeared with a smearing width of 1.0 Å and is distributed in equal portions to the midpoints of the bonds between the MM boundary atom and the MM atoms bonded to it; in the balanced redistributed charge-2 (BRC2) scheme, the adjusted MM boundary charge is distributed as point charges in equal portions to the MM atoms that are bonded to the MM boundary atom. The QM subsystem is capped by a fluorine atom that is tuned to reproduce the sum of partial atomic charges of the uncapped portion of the QM subsystem. The new aspect of the present study is a new way to carry out the tuning process; in particular, the CM5 charge model, rather than the Mulliken population analysis applied in previous studies, is used for tuning the capping atom that terminates the dangling bond of the QM region. The mean unsigned error (MUE) of the QM/MM deprotonation energy for a 15-system test suite of deprotonation reactions is 2.3 kcal/mol for the tuned BSRC scheme (TBSRC) and 2.4 kcal/mol for the tuned BRC2 scheme (TBRC2). As was the case for the original tuning method based on Mulliken charges, the new tuning method performs much better than using conventional hydrogen link atoms, which have an MUE on this test set of about 7 kcal/mol. However, the new scheme eliminates the need to use small basis sets, which can be problematic, and it allows one to be more consistent by tuning the parameters with whatever basis set is appropriate for applications. (Alternatively, since the tuning parameters and partial charges

  13. A kinetic Monte Carlo model with improved charge injection model for the photocurrent characteristics of organic solar cells

    Science.gov (United States)

    Kipp, Dylan; Ganesan, Venkat

    2013-06-01

    We develop a kinetic Monte Carlo model for photocurrent generation in organic solar cells that demonstrates improved agreement with experimental illuminated and dark current-voltage curves. In our model, we introduce a charge injection rate prefactor to correct for the electrode grid-size and electrode charge density biases apparent in the coarse-grained approximation of the electrode as a grid of single occupancy, charge-injecting reservoirs. We use the charge injection rate prefactor to control the portion of dark current attributed to each of four kinds of charge injection. By shifting the dark current between electrode-polymer pairs, we align the injection timescales and expand the applicability of the method to accommodate ohmic energy barriers. We consider the device characteristics of the ITO/PEDOT/PSS:PPDI:PBTT:Al system and demonstrate the manner in which our model captures the device charge densities unique to systems with small injection energy barriers. To elucidate the defining characteristics of our model, we first demonstrate the manner in which charge accumulation and band bending affect the shape and placement of the various current-voltage regimes. We then discuss the influence of various model parameters upon the current-voltage characteristics.

  14. Status of the Charged Higgs Boson in Two Higgs Doublet Models arXiv

    CERN Document Server

    Arbey, A.; Stal, O.; Stefaniak, T.

    The existence of charged Higgs boson(s) is inevitable in models with two (or more) Higgs doublets. Hence, their discovery would constitute unambiguous evidence for new physics beyond the Standard Model (SM). Taking into account all relevant results from direct charged and neutral Higgs boson searches at LEP and the LHC, as well as the most recent constraints from flavour physics, we present a detailed analysis of the current phenomenological status of the charged Higgs sector in a variety of well-motivated Two Higgs Doublet Models (2HDMs). We find that charged Higgs bosons as light as 75 GeV can still be compatible with the combined data, although this implies severely suppressed charged Higgs couplings to all fermions. In more popular models, e.g. the 2HDM of Type II, we find that flavour physics observables impose a combined lower limit on the charged Higgs mass of M_H+ > 600 GeV - independent of tan(beta) - which increases to M_H+ > 650 GeV for tan(beta) < 1. We furthermore find that in certain scenario...

  15. Luttinger liquid versus charge density wave behaviour in the one-dimensional spinless fermion Holstein model

    Energy Technology Data Exchange (ETDEWEB)

    Fehske, H. [Institut fuer Physik, Universitaet Greifswald, D-17487 Greifswald (Germany)]. E-mail: fehske@physik.uni-greifswald.de; Wellein, G. [Regionales Rechenzentrum Erlangen, Universitaet Erlangen-Nuernberg (Germany); Hager, G. [Regionales Rechenzentrum Erlangen, Universitaet Erlangen-Nuernberg (Germany); Weisse, A. [School of Physics, University of New South Wales, Sydney, NSW 2052 (Australia); Becker, K.W. [Institut fuer Theoretische Physik, TU Dresden, D-01062 Dresden (Germany); Bishop, A.R. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2005-04-30

    We discuss the nature of the different ground states of the half-filled Holstein model of spinless fermions in 1D. In the metallic regime we determine the renormalised effective coupling constant and the velocity of the charge excitations by a density-matrix renormalisation group (DMRG) finite-size scaling approach. At low (high) phonon frequencies the Luttinger liquid is characterised by an attractive (repulsive) effective interaction. In the charge-density wave Peierls-distorted state the charge structure factor scales to a finite value indicating long-range order.

  16. An application of artificial neural network models to estimate air temperature data in areas with sparse network of meteorological stations.

    Science.gov (United States)

    Chronopoulos, Kostas I; Tsiros, Ioannis X; Dimopoulos, Ioannis F; Alvertos, Nikolaos

    2008-12-01

    In this work artificial neural network (ANN) models are developed to estimate meteorological data values in areas with sparse meteorological stations. A more traditional interpolation model (multiple regression model, MLR) is also used to compare model results and performance. The application site is a canyon in a National Forest located in southern Greece. Four meteorological stations were established in the canyon; the models were then applied to estimate air temperature values as a function of the corresponding values of one or more reference stations. The evaluation of the ANN model results showed that fair to very good air temperature estimations may be achieved depending on the number of the meteorological stations used as reference stations. In addition, the ANN model was found to have better performance than the MLR model: mean absolute error values were found to be in the range 0.82-1.72 degrees C and 0.90-1.81 degrees C, for the ANN and the MLR models, respectively. These results indicate that ANN models may provide advantages over more traditional models or methods for temperature and other data estimations in areas where meteorological stations are sparse; they may be adopted, therefore, as an important component in various environmental modeling and management studies.

  17. Charge state evolution in the solar wind. III. Model comparison with observations

    Energy Technology Data Exchange (ETDEWEB)

    Landi, E.; Oran, R.; Lepri, S. T.; Zurbuchen, T. H.; Fisk, L. A.; Van der Holst, B. [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI 48109 (United States)

    2014-08-01

    We test three theoretical models of the fast solar wind with a set of remote sensing observations and in-situ measurements taken during the minimum of solar cycle 23. First, the model electron density and temperature are compared to SOHO/SUMER spectroscopic measurements. Second, the model electron density, temperature, and wind speed are used to predict the charge state evolution of the wind plasma from the source regions to the freeze-in point. Frozen-in charge states are compared with Ulysses/SWICS measurements at 1 AU, while charge states close to the Sun are combined with the CHIANTI spectral code to calculate the intensities of selected spectral lines, to be compared with SOHO/SUMER observations in the north polar coronal hole. We find that none of the theoretical models are able to completely reproduce all observations; namely, all of them underestimate the charge state distribution of the solar wind everywhere, although the levels of disagreement vary from model to model. We discuss possible causes of the disagreement, namely, uncertainties in the calculation of the charge state evolution and of line intensities, in the atomic data, and in the assumptions on the wind plasma conditions. Last, we discuss the scenario where the wind is accelerated from a region located in the solar corona rather than in the chromosphere as assumed in the three theoretical models, and find that a wind originating from the corona is in much closer agreement with observations.

  18. Aniline dimers and trimers as model compounds for polyaniline: steric control of charge separation properties

    Science.gov (United States)

    Kapelle, Sabine; Rettig, Wolfgang; Lapouyade, René

    2001-11-01

    The photophysical properties of several derivatives of 4-aminodiphenylamine (ADPA), model compounds of aniline dimers and trimers are investigated. Several compounds show dual fluorescence with a charge transfer (CT) component with a significantly reduced fluorescence rate constant which can be suppressed by bridging and enhanced by sterically hindering substituents, in close similarity to the compounds showing twisted intramolecular charge transfer (TICT). The relation to polyaniline (PANI) conductivity is also discussed.

  19. Extended Holstein small polaron model for charge transfer in dry DNA.

    Science.gov (United States)

    Wang, Yi; Fu, Liang; Wang, Ke-Lin

    2006-01-20

    In this paper, the charge transfer problem in dry DNA was investigated by employing an extended Holstein small polaron model with external potential traps being involved in consideration. The ground state energy and the probability amplitude of polaron in various DNA chains with different external trap potentials were obtained by variational method with the trial function being taken in coherent state form. The stability of transfered charges in various circumstances was discussed accordingly.

  20. Model test research on effect of flow accelerating-board in a pumping station

    Science.gov (United States)

    Ding, Yuan; Li, TongChun; Liu, XiaoQing; Guo, Yun; Zhou, MinZhe

    2017-09-01

    Generally, the sedimentation in the forebay of pumping station may result in bad flow patterns, which will decrease efficiency of pump device and cause the vibration of pump house and units, or other safety problems. To research the improvement of this impact in an actual project, a physical model test was established for the original scheme of one pumping station. One part of results show that the flow velocity in the channel of regulating-pool is low under the high-water level condition, and it's easy to cause the sedimentation in the regulating-pool. According to this problem, we propose a flow accelerating-board scheme for the regulating-pool. The final results show that this scheme could effectively increase the flow velocity at the bottom and reduce the sedimentation in the regulating-pool. Although the hydraulic loss of regulating-pool increased, it could be able to satisfy the design requirements.

  1. Recent advances in understanding lunar surface charging: modeling, theory and spacecraft observations

    Science.gov (United States)

    Poppe, A.; Halekas, J. S.; Delory, G. T.; Horanyi, M.; Angelopoulos, V.; Farrell, W. M.

    2012-12-01

    As an airless body in space, the Moon is exposed to a combination of ambient plasma and solar ultraviolet radiation that cause the lunar surface to electrostatically charge in response to these currents. Our understanding of lunar surface charging typically holds that the dayside surface reaches equilibrium potentials of a few volts positive, with a generally smooth transition to larger, negative potentials near the terminators and on the nightside. While much of this picture may hold true, there are several situations in which the lunar surface charge and the associated electrostatic potential do not conform to this picture. These instances include areas in and around surface craters, which can locally shadow the lunar surface, and times when the Moon is within the terrestrial plasma sheet and magnetotail lobes. We present a combination of results regarding lunar surface charging from recent three-dimensional plasma modeling, theoretical charging calculations, and analysis of in-situ measurements by the Lunar Prospector and ARTEMIS missions. We discuss the implications of these findings for other geophysical investigations, including measurements of pick-up ions from the surface and exosphere, the behavior of electrostatically charged dust, and the possible charging environments of other airless bodies throughout the solar system.

  2. Computational models of an inductive power transfer system for electric vehicle battery charge

    Science.gov (United States)

    Anele, A. O.; Hamam, Y.; Chassagne, L.; Linares, J.; Alayli, Y.; Djouani, K.

    2015-09-01

    One of the issues to be solved for electric vehicles (EVs) to become a success is the technical solution of its charging system. In this paper, computational models of an inductive power transfer (IPT) system for EV battery charge are presented. Based on the fundamental principles behind IPT systems, 3 kW single phase and 22 kW three phase IPT systems for Renault ZOE are designed in MATLAB/Simulink. The results obtained based on the technical specifications of the lithium-ion battery and charger type of Renault ZOE show that the models are able to provide the total voltage required by the battery. Also, considering the charging time for each IPT model, they are capable of delivering the electricity needed to power the ZOE. In conclusion, this study shows that the designed computational IPT models may be employed as a support structure needed to effectively power any viable EV.

  3. Charged ρ Meson Condensate in Neutron Stars within RMF Models

    Directory of Open Access Journals (Sweden)

    Konstantin A. Maslov

    2017-12-01

    Full Text Available Knowledge of the equation of state (EoS of cold and dense baryonic matter is essential for the description of properties of neutron stars (NSs. With an increase of the density, new baryon species can appear in NS matter, as well as various meson condensates. In previous works, we developed relativistic mean-field (RMF models with hyperons and Δ -isobars, which passed the majority of known experimental constraints, including the existence of a 2 M ⊙ neutron star. In this contribution, we present results of the inclusion of ρ − -meson condensation into these models. We have shown that, in one class of the models (so-called KVOR-based models, in which the additional stiffening procedure is introduced in the isoscalar sector, the condensation gives only a small contribution to the EoS. In another class of the models (MKVOR-based models with additional stiffening in isovector sector, the condensation can lead to a first-order phase transition and a substantial decrease of the NS mass. Nevertheless, in all resulting models, the condensation does not spoil the description of the experimental constraints.

  4. Modeling of radiation-induced charge trapping in MOS devices under ionizing irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Petukhov, M. A., E-mail: m.a.petukhov@gmail.com; Ryazanov, A. I. [National Research Center Kurchatov Institute (Russian Federation)

    2016-12-15

    The numerical model of the radiation-induced charge trapping process in the oxide layer of a MOS device under ionizing irradiation is developed; the model includes carrier transport, hole capture by traps in different states, recombination of free electrons and trapped holes, kinetics of hydrogen ions which can be accumulated in the material during transistor manufacture, and accumulation and charging of interface states. Modeling of n-channel MOSFET behavior under 1 MeV photon irradiation is performed. The obtained dose dependences of the threshold voltage shift and its contributions from trapped holes and interface states are in good agreement with experimental data.

  5. Modeling Electrostatic Fields Generated by Internal Charging of Materials in Space Radiation Environments

    Science.gov (United States)

    Minow, Joseph I.

    2011-01-01

    Internal charging is a risk to spacecraft in energetic electron environments. DICTAT, NU MIT computational codes are the most widely used engineering tools for evaluating internal charging of insulator materials exposed to these environments. Engineering tools are designed for rapid evaluation of ESD threats, but there is a need for more physics based models for investigating the science of materials interactions with energetic electron environments. Current tools are limited by the physics included in the models and ease of user implementation .... additional development work is needed to improve models.

  6. Multiphasic modeling of charged solute transport across articular cartilage: Application of multi-zone finite-bath model.

    Science.gov (United States)

    Arbabi, Vahid; Pouran, Behdad; Weinans, Harrie; Zadpoor, Amir A

    2016-06-14

    Charged and uncharged solutes penetrate through cartilage to maintain the metabolic function of chondrocytes and to possibly restore or further breakdown the cartilage tissue in different stages of osteoarthritis. In this study the transport of charged solutes across the various zones of cartilage was quantified, taken into account the physicochemical interactions between the solute and the cartilage constituents. A multiphasic finite-bath finite element (FE) model was developed to simulate equine cartilage diffusion experiments that used a negatively charged contrast agent (ioxaglate) in combination with serial micro-computed tomography (micro-CT) to measure the diffusion. By comparing the FE model with the experimental data both the diffusion coefficient of ioxaglate and the fixed charge density (FCD) were obtained. In the multiphasic model, cartilage was divided into multiple (three) zones to help understand how diffusion coefficient and FCD vary across cartilage thickness. The direct effects of charged solute-FCD interaction on diffusion were investigated by comparing the diffusion coefficients derived from the multiphasic and biphasic-solute models. We found a relationship between the FCD obtained by the multiphasic model and ioxaglate partitioning obtained from micro-CT experiments. Using our multi-zone multiphasic model, diffusion coefficient of the superficial zone was up to ten-fold higher than that of the middle zone, while the FCD of the middle zone was up to almost two-fold higher than that of the superficial zone. In conclusion, the developed finite-bath multiphasic model provides us with a non-destructive method by which we could obtain both diffusion coefficient and FCD of different cartilage zones. The outcomes of the current work will also help understand how charge of the bath affects the diffusion of a charged molecule and also predict the diffusion behavior of a charged solute across articular cartilage. Copyright © 2016 Elsevier Ltd. All

  7. NEMO. A novel techno-economic tool suite for simulating and optimizing solutions for grid integration of electric vehicles and charging stations

    Energy Technology Data Exchange (ETDEWEB)

    Erge, Thomas; Stillahn, Thies; Dallmer-Zerbe, Kilian; Wille-Haussmann, Bernhard [Frauenhofer Institut for Solar Energy Systems ISE, Freiburg (Germany)

    2013-07-01

    With an increasing use of electric vehicles (EV) grid operators need to predict energy flows depending on electromobility use profiles to accordingly adjust grid infrastructure and operation control accordingly. Tools and methodologies are required to characterize grid problems resulting from the interconnection of EV with the grid. The simulation and optimization tool suite NEMO (Novel E-MObility grid model) was developed within a European research project and is currently being tested using realistic showcases. It is a combination of three professional tools. One of the tools aims at a combined techno-economic design and operation, primarily modeling plants on contracts or the spot market, at the same time participating in balancing markets. The second tool is designed for planning grid extension or reinforcement while the third tool is mainly used to quickly discover potential conflicts of grid operation approaches through load flow analysis. The tool suite is used to investigate real showcases in Denmark, Germany and the Netherlands. First studies show that significant alleviation of stress on distribution grid lines could be achieved by few but intelligent restrictions to EV charging procedures.

  8. Electro-osmosis in inhomogeneously charged microporous media by pore-scale modeling.

    Science.gov (United States)

    Zhang, Li; Wang, Moran

    2017-01-15

    Surface charge at solid-electrolyte interface is generally coupled with the local electrolyte properties (ionic concentration, pH, etc.), and therefore not as assumed homogeneous on the solid surfaces in the previous studies. The inhomogeneous charge brings huge challenges in predictions of electro-osmotic transport and has never been well studied. In this work, we first propose a classification of electro-osmosis based on a dimensionless number which is the ratio of the Debye length to the characteristic pore size. In the limit of thin electrical double layer, we establish a pore-scale numerical model for inhomogeneously charged electro-osmosis including four ions: Na(+),Cl(-),H(+) and OH(-). Based on reconstructed porous media, we simulate the electro-osmosis with inhomogeneous charge using lattice Boltzmann method. The nonlinear response of electro-osmotic velocity to applied electrical field and the reverse flow have been observed and analyzed. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Maxwell–Wagner Effect in Multi-Layered Dielectrics: Interfacial Charge Measurement and Modelling

    Directory of Open Access Journals (Sweden)

    Thi Thu Nga Vu

    2017-05-01

    Full Text Available The development of high voltage direct current (HVDC technologies generates new paradigms in research. In particular and contrary to the AC case, investigation of electrical conduction is not only needed for understanding the dielectric breakdown but also to describe the field distribution inside the insulation. Here, we revisit the so-called Maxwell–Wagner effect in multi-layered dielectrics by considering on the one hand a non-linear field dependent model of conductivity and on the other hand by performing space charge measurements giving access to the interfacial charge accumulated between different dielectrics. We show that space charge measurements give access to the amount of interfacial charge built-up by the Maxwell–Wagner effect between two dielectrics of different natures. Measurements also demonstrate that the field distribution undergoes a transition from a capacitive distribution to a resistive one, under long lasting stress.

  10. Extended charge banking model of dual path shocks for implantable cardioverter defibrillators.

    Science.gov (United States)

    Dosdall, Derek J; Sweeney, James D

    2008-08-01

    Single path defibrillation shock methods have been improved through the use of the Charge Banking Model of defibrillation, which predicts the response of the heart to shocks as a simple resistor-capacitor (RC) circuit. While dual path defibrillation configurations have significantly reduced defibrillation thresholds, improvements to dual path defibrillation techniques have been limited to experimental observations without a practical model to aid in improving dual path defibrillation techniques. The Charge Banking Model has been extended into a new Extended Charge Banking Model of defibrillation that represents small sections of the heart as separate RC circuits, uses a weighting factor based on published defibrillation shock field gradient measures, and implements a critical mass criteria to predict the relative efficacy of single and dual path defibrillation shocks. The new model reproduced the results from several published experimental protocols that demonstrated the relative efficacy of dual path defibrillation shocks. The model predicts that time between phases or pulses of dual path defibrillation shock configurations should be minimized to maximize shock efficacy. Through this approach the Extended Charge Banking Model predictions may be used to improve dual path and multi-pulse defibrillation techniques, which have been shown experimentally to lower defibrillation thresholds substantially. The new model may be a useful tool to help in further improving dual path and multiple pulse defibrillation techniques by predicting optimal pulse durations and shock timing parameters.

  11. Link between hopping models and percolation scaling laws for charge transport in mixtures of small molecules

    Directory of Open Access Journals (Sweden)

    Dong-Gwang Ha

    2016-04-01

    Full Text Available Mixed host compositions that combine charge transport materials with luminescent dyes offer superior control over exciton formation and charge transport in organic light emitting devices (OLEDs. Two approaches are typically used to optimize the fraction of charge transport materials in a mixed host composition: either an empirical percolative model, or a hopping transport model. We show that these two commonly-employed models are linked by an analytic expression which relates the localization length to the percolation threshold and critical exponent. The relation is confirmed both numerically and experimentally through measurements of the relative conductivity of Tris(4-carbazoyl-9-ylphenylamine (TCTA :1,3-bis(3,5-dipyrid-3-yl-phenylbenzene (BmPyPb mixtures with different concentrations, where the TCTA plays a role as hole conductor and the BmPyPb as hole insulator. The analytic relation may allow the rational design of mixed layers of small molecules for high-performance OLEDs.

  12. Model simulations of the radioactive material plumes in the Fukushima nuclear power station accident

    Science.gov (United States)

    Nakajima, Teruyuki; Goto, Daisuke; Morino, Yu; Misawa, Shota; Tsuruta, Haruo; Uchida, Junya; Takemura, Toshihiko; Ohara, Toshimasa; Oura, Yasuji; Ebihara, Mitsuru; Satoh, Masaki

    2017-04-01

    We like to present an analysis of a model-simulated and observed data comparison for depiction of the atmospheric transportation of the 137Cs emitted from the Fukushima Daiichi Nuclear Power Station accident. This method employs a combination of the results of two aerosol model ensembles and the hourly observed atmospheric 137Cs concentration during 14-23 March 2011 at 90 sites in the Suspended Particulate Matter monitoring network. The result elucidates accurate transport routes and the distribution of the surface-level atmospheric 137Cs relevant to eight plume events that were previously identified. The model ensemble simulates the main features of the observed distribution of surface-level atmospheric 137Cs. However, significant differences were found in some cases. Through the analysis we discuss the important processes to control the characteristic shape and movement of each plume. We also report the status of the 2nd international model intercomparison in progress.

  13. An Research on Electrical Vehicle'S Charge-Discharge Behavior Based on Logit Model

    Science.gov (United States)

    Xiaoyin, Wang; Junyong, Liu

    Electric Vehicle is the future trend of the automobile industry, and the energy exchanging between the electrical vehicles and the grid through the vehicle-to-grid (V2G) technology becomes possiable. V2G leads to a rapid load growth effecting the benefit of the grid, which wasn't discussed. The charge and discharge model of the electrical vehicles is discussed using the multinomial logit model based on the discrete choice theory, then preliminarily evaluates the effects of economic benefit both on the motorist and the grid. Finally, suggestions on period division and electricity pricing for charge and discharge of the electrical vehicle are given.

  14. Modeling carrier density dependent charge transport in semiconducting carbon nanotube networks

    Science.gov (United States)

    Schießl, Stefan P.; de Vries, Xander; Rother, Marcel; Massé, Andrea; Brohmann, Maximilian; Bobbert, Peter A.; Zaumseil, Jana

    2017-09-01

    Charge transport in a network of only semiconducting single-walled carbon nanotubes is modeled as a random-resistor network of tube-tube junctions. Solving Kirchhoff's current law with a numerical solver and taking into account the one-dimensional density of states of the nanotubes enables the evaluation of carrier density dependent charge transport properties such as network mobility, local power dissipation, and current distribution. The model allows us to simulate and investigate mixed networks that contain semiconducting nanotubes with different diameters, and thus different band gaps and conduction band edge energies. The obtained results are in good agreement with available experimental data.

  15. Links between the charge model and bonded parameter force constants in biomolecular force fields

    Science.gov (United States)

    Cerutti, David S.; Debiec, Karl T.; Case, David A.; Chong, Lillian T.

    2017-10-01

    The ff15ipq protein force field is a fixed charge model built by automated tools based on the two charge sets of the implicitly polarized charge method: one set (appropriate for vacuum) for deriving bonded parameters and the other (appropriate for aqueous solution) for running simulations. The duality is intended to treat water-induced electronic polarization with an understanding that fitting data for bonded parameters will come from quantum mechanical calculations in the gas phase. In this study, we compare ff15ipq to two alternatives produced with the same fitting software and a further expanded data set but following more conventional methods for tailoring bonded parameters (harmonic angle terms and torsion potentials) to the charge model. First, ff15ipq-Qsolv derives bonded parameters in the context of the ff15ipq solution phase charge set. Second, ff15ipq-Vac takes ff15ipq's bonded parameters and runs simulations with the vacuum phase charge set used to derive those parameters. The IPolQ charge model and associated protocol for deriving bonded parameters are shown to be an incremental improvement over protocols that do not account for the material phases of each source of their fitting data. Both force fields incorporating the polarized charge set depict stable globular proteins and have varying degrees of success modeling the metastability of short (5-19 residues) peptides. In this particular case, ff15ipq-Qsolv increases stability in a number of α -helices, correctly obtaining 70% helical character in the K19 system at 275 K and showing appropriately diminishing content up to 325 K, but overestimating the helical fraction of AAQAA3 by 50% or more, forming long-lived α -helices in simulations of a β -hairpin, and increasing the likelihood that the disordered p53 N-terminal peptide will also form a helix. This may indicate a systematic bias imparted by the ff15ipq-Qsolv parameter development strategy, which has the hallmarks of strategies used to develop

  16. Event-driven model predictive control of sewage pumping stations for sulfide mitigation in sewer networks.

    Science.gov (United States)

    Liu, Yiqi; Ganigué, Ramon; Sharma, Keshab; Yuan, Zhiguo

    2016-07-01

    Chemicals such as Mg(OH)2 and iron salts are widely dosed to sewage for mitigating sulfide-induced corrosion and odour problems in sewer networks. The chemical dosing rate is usually not automatically controlled but profiled based on experience of operators, often resulting in over- or under-dosing. Even though on-line control algorithms for chemical dosing in single pipes have been developed recently, network-wide control algorithms are currently not available. The key challenge is that a sewer network is typically wide-spread comprising many interconnected sewer pipes and pumping stations, making network-wide sulfide mitigation with a relatively limited number of dosing points challenging. In this paper, we propose and demonstrate an Event-driven Model Predictive Control (EMPC) methodology, which controls the flows of sewage streams containing the dosed chemical to ensure desirable distribution of the dosed chemical throughout the pipe sections of interests. First of all, a network-state model is proposed to predict the chemical concentration in a network. An EMPC algorithm is then designed to coordinate sewage pumping station operations to ensure desirable chemical distribution in the network. The performance of the proposed control methodology is demonstrated by applying the designed algorithm to a real sewer network simulated with the well-established SeweX model using real sewage flow and characteristics data. The EMPC strategy significantly improved the sulfide mitigation performance with the same chemical consumption, compared to the current practice. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Quantification of the solid-state charge mobility in a model radical polymer

    Energy Technology Data Exchange (ETDEWEB)

    Baradwaj, Aditya G.; Rostro, Lizbeth; Boudouris, Bryan W., E-mail: boudouris@purdue.edu [School of Chemical Engineering, Purdue University, 480 Stadium Mall Drive, West Lafayette, Indiana 47907 (United States); Alam, Muhammad A. [School of Electrical and Computer Engineering, Purdue University, 475 Northwestern Avenue, West Lafayette, Indiana 47907 (United States)

    2014-05-26

    We establish that an oft-used radical polymer, poly(2,2,6,6-tetramethylpiperidinyloxy methacrylate) (PTMA), has a solid-state hole mobility value on the order of 10{sup −4} cm{sup 2} V{sup −1} s{sup −1} in a space charge-limited device geometry. Despite being completely amorphous and lacking any π-conjugation, these results demonstrate that the hole mobility of PTMA is comparable to many well-studied conjugated polymers [e.g., poly(3-hexylthiophene)]. Furthermore, we show that the space charge-limited charge carrier mobility of these macromolecules is only a weak function of temperature, in contrast to many thermally-activated models of charge transport in polymeric materials. This key result demonstrates that the charge transport in radical polymers is inherently different than that in semicrystalline, conjugated polymers. These results establish the mechanism of solid-state charge transport in radical polymers and provide macromolecular design principles for this emerging class of organic electronic materials.

  18. Modeling the Spin Motor Current of the International Space Station's Control Moment Gyroscopes

    Science.gov (United States)

    Pereira, Miguel A.

    2008-01-01

    The International Space Station (ISS) attitude control is provided by two means: The Russian Segment uses thrusters and the U.S. Segment uses double-gimbaled control moment gyroscopes (CMG). CMGs are used as momentum exchange devices, providing non propulsive attitude control for the vehicle. The CMGs are very important for the ISS program because, first, they save propellant - which needs to be transferred to the Station in special cargo vehicles - and, second, they provide the microgravity environment on the Station - which is necessary for scientific experiments planned for the ISS mission. Since 2002, when one of the CMG on the ISS failed, all CMGs are closely monitored. High gimbal rates, vibration spikes, unusual variations of spin motor current and bearing temperatures are of great concern, since these parameters are the CMG health indicators. The telemetry analysis of these and some other CMG parameters is used to determine constrains and make changes to the CMGs operation on board. These CMG limitations, in turn, may limit the ISS attitude control capabilities and may be critical to ISS operation. Therefore, it is important to know whether the CMG parameter is nominal or out of family, and why. The goal of this project is to analyze an important CMG parameter - spin motor current. Some operational decisions are made now based on the spin motor current signatures. The spin motor current depends on gimbal rates, ISS rates, and spin bearing friction. The spin bearing friction in turn depends on the bearing temperatures, wheel rates, normal load - which is a function of gimbal and wheel rates - lubrication, etc. The first task of this project is to create a spin motor current mathematical model based on CMG dynamics model and the current knowledge on bearing friction in microgravity.

  19. Community-aware charging station network design for electrified vehicles in urban areas : reducing congestion, emissions, improving accessibility, and promoting walking, bicycling, and use of public transportation.

    Science.gov (United States)

    2016-08-31

    A major challenge for achieving large-scale adoption of EVs is an accessible infrastructure for the communities. The societal benefits of large-scale adoption of EVs cannot be realized without adequate deployment of publicly accessible charging stati...

  20. What input data are needed to accurately model electromagnetic fields from mobile phone base stations?

    Science.gov (United States)

    Beekhuizen, Johan; Kromhout, Hans; Bürgi, Alfred; Huss, Anke; Vermeulen, Roel

    2015-01-01

    The increase in mobile communication technology has led to concern about potential health effects of radio frequency electromagnetic fields (RF-EMFs) from mobile phone base stations. Different RF-EMF prediction models have been applied to assess population exposure to RF-EMF. Our study examines what input data are needed to accurately model RF-EMF, as detailed data are not always available for epidemiological studies. We used NISMap, a 3D radio wave propagation model, to test models with various levels of detail in building and antenna input data. The model outcomes were compared with outdoor measurements taken in Amsterdam, the Netherlands. Results showed good agreement between modelled and measured RF-EMF when 3D building data and basic antenna information (location, height, frequency and direction) were used: Spearman correlations were >0.6. Model performance was not sensitive to changes in building damping parameters. Antenna-specific information about down-tilt, type and output power did not significantly improve model performance compared with using average down-tilt and power values, or assuming one standard antenna type. We conclude that 3D radio wave propagation modelling is a feasible approach to predict outdoor RF-EMF levels for ranking exposure levels in epidemiological studies, when 3D building data and information on the antenna height, frequency, location and direction are available.

  1. Computer Modeling Reveals that Modifications of the Histone Tail Charges Define Salt-Dependent Interaction of the Nucleosome Core Particles

    OpenAIRE

    Yang, Ye; Lyubartsev, Alexander P.; Korolev, Nikolay; Nordenskiöld, Lars

    2009-01-01

    Coarse-grained Langevin molecular dynamics computer simulations were conducted for systems that mimic solutions of nucleosome core particles (NCPs). The NCP was modeled as a negatively charged spherical particle representing the complex of DNA and the globular part of the histones combined with attached strings of connected charged beads modeling the histone tails. The size, charge, and distribution of the tails relative to the core were built to match real NCPs. Three models of NCPs were con...

  2. Generalized moving boundary model for charge-discharge of LiFePO4/C cells

    Science.gov (United States)

    Khandelwal, Ashish; Hariharan, Krishnan S.; Senthil Kumar, V.; Gambhire, Priya; Kolake, Subramanya Mayya; Oh, Dukjin; Doo, Seokgwang

    2014-02-01

    Lithium ion cells with electrode materials that undergo phase transitions, like LiFePO4, have unique charge-discharge characteristics. In this work a generalized framework of moving boundary approach is proposed to model the path dependent charge-discharge response of porous electrodes that exhibit multi-phase coexistence. Using the Landau transformation the governing equation in moving coordinate is transformed to fixed coordinate and a suitable path dependent algorithm is devised and is implemented in a multi-physics environment. Simulation results show that tangential propagation of the phase front, often seen in experiments, can be addressed by this model. Incorporation of multi-phase diffusion predicts the characteristic phase separation in LiFePO4 particles. The proposed model successfully captures the charge-discharge asymmetry of LiFePO4 based cells. Efficacy of the proposed approach to model the path dependence of cells with phase change electrodes is demonstrated by simulating the response of LiFePO4/graphite cell subjected to a charge-discharge pulse. Numerical studies are performed to study the effect of important model parameters to enhance cell design and to bring out unique features in the cell response due to multi-phase coexistence.

  3. Analysis of effectiveness of possible queuing models at gas stations using the large-scale queuing theory

    Directory of Open Access Journals (Sweden)

    Slaviša M. Ilić

    2011-10-01

    Full Text Available This paper analyzes the effectiveness of possible models for queuing at gas stations, using a mathematical model of the large-scale queuing theory. Based on actual data collected and the statistical analysis of the expected intensity of vehicle arrivals and queuing at gas stations, the mathematical modeling of the real process of queuing was carried out and certain parameters quantified, in terms of perception of the weaknesses of the existing models and the possible benefits of an automated queuing model.

  4. A model with charges and polarizability for CS₂ in an ionic liquid

    Indian Academy of Sciences (India)

    The environment of a solute molecule in an ionic liquid is likely to have large fluctuating electrostatic fields, and so the electrostatic properties of such a solute including its charge distribution and its polarizability may make a difference to both its static and dynamic properties. We have developed a new model forthe static ...

  5. University Students' Explanatory Models of the Interactions between Electric Charges and Magnetic Fields

    Science.gov (United States)

    Saglam, Murat

    2010-01-01

    This study aimed to investigate the models that co-existed in students' cognitive structure to explain the interactions between electric charges and uniform magnetic fields. The sample consisted of 129 first-year civil engineering, geology and geophysics students from a large state university in western Turkey. The students answered five…

  6. Cosmic ray muon charge ratio derived from the new scaling variable model

    CERN Document Server

    Bhattacharya, D P

    1980-01-01

    The charge ratio of sea level muons has been estimated from the new scaling variable model and the CERN Intersecting Storage Ring data of Capiluppi et al. (1974) for pp to pi /sup +or-/X and pp to K/sup +or- /X inclusive reactions. The estimated muon charge ratio is found to be 1.21 and the result has been compared with the experimental data of Parker et al. (1969), Burnet et al. (1973), Ashley et al., and Muraki et al. (1979). (20 refs).

  7. Nuclear monopole charge form factor calculation for relativistic models including center-of-mass corrections

    Energy Technology Data Exchange (ETDEWEB)

    Avancini, S.S.; Marinelli, J.R. [Universidade Federal de Santa Catarina Florianopolis, Depto de Fisica - CFM, Florianopolis (Brazil); Carlson, B.V. [Instituto Tecnologico de Aeronautica, Sao Jose dos Campos (Brazil)

    2013-06-15

    Relativistic models for finite nuclei contain spurious center-of-mass motion in most applications for the nuclear many-body problem, where the nuclear wave function is taken as a single Slater determinant within a space-fixed frame description. We use the Peierls-Yoccoz projection method, previously developed for relativistic approaches together with a reparametrization of the coupling constants that fits binding energies and charge radius and apply our results to calculate elastic electron scattering monopole charge form factors for light nuclei. (orig.)

  8. Models for the transient stability of conventional power generating stations connected to low inertia systems

    Science.gov (United States)

    Zarifakis, Marios; Coffey, William T.; Kalmykov, Yuri P.; Titov, Sergei V.

    2017-06-01

    An ever-increasing requirement to integrate greater amounts of electrical energy from renewable sources especially from wind turbines and solar photo-voltaic installations exists and recent experience in the island of Ireland demonstrates that this requirement influences the behaviour of conventional generating stations. One observation is the change in the electrical power output of synchronous generators following a transient disturbance especially their oscillatory behaviour accompanied by similar oscillatory behaviour of the grid frequency, both becoming more pronounced with reducing grid inertia. This behaviour cannot be reproduced with existing mathematical models indicating that an understanding of the behaviour of synchronous generators, subjected to various disturbances especially in a system with low inertia requires a new modelling technique. Thus two models of a generating station based on a double pendulum described by a system of coupled nonlinear differential equations and suitable for analysis of its stability corresponding to infinite or finite grid inertia are presented. Formal analytic solutions of the equations of motion are given and compared with numerical solutions. In particular the new finite grid model will allow one to identify limitations to the operational range of the synchronous generators used in conventional power generation and also to identify limits, such as the allowable Rate of Change of Frequency which is currently set to ± 0.5 Hz/s and is a major factor in describing the volatility of a grid as well as identifying requirements to the total inertia necessary, which is currently provided by conventional power generators only, thus allowing one to maximise the usage of grid connected non-synchronous generators, e.g., wind turbines and solar photo-voltaic installations.

  9. THE ADEQUACY OF MATHEMATICAL MODELS FOR DETERMINATION OF THE PERFORMANCE OF THE WORK STATION

    Directory of Open Access Journals (Sweden)

    R. H. Korobyova

    2009-04-01

    Full Text Available Different estimation methods of technical and technological parameters of railway stations are considered. Results of the parameters comparison obtained on the basis of the station work graph and simulation with functioning parameters of a real station are presented.

  10. Nearest-Neighbor Repulsion and Competing Charge and Spin Order in the Extended Hubbard Model.

    Science.gov (United States)

    Bahman, Davoudi; Tremblay, A.-M. S.

    2006-03-01

    We generalize the Two-Particle Self-Consistent (TPSC) approach to study the extended Hubbard model where the nearest-neighbor interaction V is present in addition to the local interaction U. Our results are in good agreement with available Quantum Monte-Carlo results over the whole range of density n up to intermediate coupling. As a function of U, V and n we observe different kinds of charge and spin orders, like commensurate/incommensurate charge and spin density wave, phase separation, and ferromagnetic order. For attractive V superconductivity could exist in the regions where the other types of charge and spin orders do not dominate. Ref.: B. Davoudi and A.-M.S. Tremblay, cond-mat/0509707

  11. An atomic charge model for graphene oxide for exploring its bioadhesive properties in explicit water

    Energy Technology Data Exchange (ETDEWEB)

    Stauffer, D.; Dragneva, N.; Floriano, W. B.; Rubel, O. [Thunder Bay Regional Research Institute, 290 Munro St, Thunder Bay, Ontario P7B 6V4 (Canada); Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7A 7T1 (Canada); Mawhinney, R. C. [Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7A 7T1 (Canada); Fanchini, G. [Physics and Astronomy, University of Western Ontario, 1151 Richmond St, London, Ontario N6A 3K7 (Canada); French, S. [University of Calgary, South Health Campus, 4448 Front St. SE, Calgary, Alberta T3M 1M4 (Canada)

    2014-07-28

    Graphene Oxide (GO) has been shown to exhibit properties that are useful in applications such as biomedical imaging, biological sensors, and drug delivery. The binding properties of biomolecules at the surface of GO can provide insight into the potential biocompatibility of GO. Here we assess the intrinsic affinity of amino acids to GO by simulating their adsorption onto a GO surface. The simulation is done using Amber03 force-field molecular dynamics in explicit water. The emphasis is placed on developing an atomic charge model for GO. The adsorption energies are computed using atomic charges obtained from an ab initio electrostatic potential based method. The charges reported here are suitable for simulating peptide adsorption to GO.

  12. Analytical modeling of label free biosensor using charge plasma based gate underlap dielectric modulated MOSFET

    Science.gov (United States)

    Chanda, Manash; Das, Rahul; Kundu, Atanu; Sarkar, Chandan K.

    2017-04-01

    In this paper charge plasma based dielectric modulated four gated MOSFET (CP-GUDM-MOSFET) has been proposed for the efficacy of label free electrical detection of the biomolecules. To achieve low thermal budgeting, charge-plasma concept is employed using appropriate metal work function electrodes. Extensive simulations have been done using the Sentaurus TCAD to validate the proposed architecture. An analytical modeling has also been done on surface potential and drain current to consolidate the feasibility of the structure. Significant improvements in the on current (ION) and threshold voltage have been observed in presence of the charged biomolecules. The performance of proposed structure is found to be sensitive to gate-oxide thickness variations. High sensitivity of the proposed CP-GUDM-MOSFET based biosensor with low thermal budgeting scheme; simple structure and its compatibility with the existing CMOS processes make it an exciting alternative to the conventional FET-based biosensors.

  13. Description of Charge Radii in Halo Nuclei Within the Gamow Shell Model

    Energy Technology Data Exchange (ETDEWEB)

    Papadimitriou, G. [University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL); Michel, N. [CEA, Saclay, France; Nazarewicz, W. [University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL); Ploszajczak, M. [Grand Accelerateur National d' Ions Lourds (GANIL); Rotureau, J. [University of Arizona

    2009-01-01

    The charge radius of the halo nucleus 6He is studied within the framework of the Gamow Shell Model (GSM). The charge radius carries information about the size of the neutron halo, the recoil of the core, and the effective interaction between valence nucleons. The motivation for this work stems from the precise measurements of charge radii in 6,8He, 11Li, and 11Be. For these weakly bound nuclei, the proper treatment of the particle continuum turns out to be crucial. The GSM is a tool that can properly account for the coupling of the continuum space (of both resonant and scattering character) with that of the bound states. We use a GSM Hamiltonian written explicitly in intrinsic coordinates. This guarantees that the core recoil effect is properly described and the spurious center-of-mass motion is removed. According to our calculations for 6He, the charge radius is very sensitive to (i) the halo extent given by the two-neutron separation energy of the system, and (ii) the p3/2 occupation. In particular, we show that the two-body wave function of halo neutrons in 6He should contain ~91% of a p3/2 partial wave to reproduce the charge radius. This observation will help us to construct a GSM effective interaction on the interface of p and sd shells that is needed to describe other halo systems.

  14. Finite Field Methods for the Supercell Modelling of Charged Insulator-Electrolyte Interfaces

    CERN Document Server

    Zhang, Chao

    2016-01-01

    Surfaces of ionic solids interacting with an ionic solution can build up charge by exchange of ions. The surface charge is compensated by a strip of excess charge at the border of the electrolyte forming an electric double layer. These electric double layers are very hard to model using the supercells methods of computational condensed phase science. The problem arises when the solid is an electric insulator (as most ionic solids are) permitting a finite interior electric field over the width of the slab representing the solid in the supercell. The slab acts as a capacitor. The stored charge is a deficit in the solution failing to compensate fully for the solid surface charge. Here we show how these problems can be overcome using the finite field methods developed by Stengel, Spaldin and Vanderbilt [Nat. Phys. 5, 304, (2009)]. We also show how the capacitance of the double layer can be computed once overall electric neutrality of the double layer is restored by application of a finite macroscopic field E or a...

  15. Search for Charged Higgs Bosons at LEP in General Two Higgs Doublet Models

    CERN Document Server

    Abdallah, J.; Adam, W.; Adzic, P.; Albrecht, T.; Alderweireld, T.; Alemany-Fernandez, R.; Allmendinger, T.; Allport, P.P.; Amaldi, U.; Amapane, N.; Amato, S.; Anashkin, E.; Andreazza, A.; Andringa, S.; Anjos, N.; Antilogus, P.; Apel, W.D.; Arnoud, Y.; Ask, S.; Asman, B.; Augustin, J.E.; Augustinus, A.; Baillon, P.; Ballestrero, A.; Bambade, P.; Barbier, R.; Bardin, D.; Barker, G.; Baroncelli, A.; Battaglia, M.; Baubillier, M.; Becks, K.H.; Begalli, M.; Behrmann, A.; Ben-Haim, E.; Benekos, N.; Benvenuti, A.; Berat, C.; Berggren, M.; Berntzon, L.; Bertrand, D.; Besancon, M.; Besson, N.; Bloch, D.; Blom, M.; Bluj, M.; Bonesini, M.; Boonekamp, M.; Booth, P.S.L.; Borisov, G.; Botner, O.; Bouquet, B.; Bowcock, T.J.V.; Boyko, I.; Bracko, M.; Brenner, R.; Brodet, E.; Bruckman, P.; Brunet, J.M.; Bugge, L.; Buschmann, P.; Calvi, M.; Camporesi, T.; Canale, V.; Carena, F.; Castro, Nuno Filipe; Cavallo, F.; Chapkin, M.; Charpentier, Ph.; Checchia, P.; Chierici, R.; Chliapnikov, P.; Chudoba, J.; Chung, S.U.; Cieslik, K.; Collins, P.; Contri, R.; Cosme, G.; Cossutti, F.; Costa, M.J.; Crennell, D.; Cuevas, J.; D'Hondt, J.; Dalmau, J.; da Silva, T.; Da Silva, W.; Della Ricca, G.; De Angelis, A.; De Boer, W.; De Clercq, C.; De Lotto, B.; De Maria, N.; De Min, A.; de Paula, L.; Di Ciaccio, L.; Di Simone, A.; Doroba, K.; Drees, J.; Dris, M.; Eigen, G.; Ekelof, T.; Ellert, M.; Elsing, M.; Espirito Santo, M.C.; Fanourakis, G.; Fassouliotis, D.; Feindt, M.; Fernandez, J.; Ferrer, A.; Ferro, F.; Flagmeyer, U.; Foeth, H.; Fokitis, E.; Fulda-Quenzer, F.; Fuster, J.; Gandelman, M.; Garcia, C.; Gavillet, Ph.; Gazis, Evangelos; Gokieli, R.; Golob, B.; Gomez-Ceballos, G.; Goncalves, P.; Graziani, E.; Grosdidier, G.; Grzelak, K.; Guy, J.; Haag, C.; Hallgren, A.; Hamacher, K.; Hamilton, K.; Haug, S.; Hauler, F.; Hedberg, V.; Hennecke, M.; Herr, H.; Hoffman, J.; Holmgren, S.O.; Holt, P.J.; Houlden, M.A.; Hultqvist, K.; Jackson, John Neil; Jarlskog, G.; Jarry, P.; Jeans, D.; Johansson, Erik Karl; Johansson, P.D.; Jonsson, P.; Joram, C.; Jungermann, L.; Kapusta, Frederic; Katsanevas, S.; Katsoufis, E.; Kernel, G.; Kersevan, B.P.; Kerzel, U.; Kiiskinen, A.; King, B.T.; Kjaer, N.J.; Kluit, P.; Kokkinias, P.; Kourkoumelis, C.; Kouznetsov, O.; Krumstein, Z.; Kucharczyk, M.; Lamsa, J.; Leder, G.; Ledroit, Fabienne; Leinonen, L.; Leitner, R.; Lemonne, J.; Lepeltier, V.; Lesiak, T.; Liebig, W.; Liko, D.; Lipniacka, A.; Lopes, J.H.; Lopez, J.M.; Loukas, D.; Lutz, P.; Lyons, L.; MacNaughton, J.; Malek, A.; Maltezos, S.; Mandl, F.; Marco, J.; Marco, R.; Marechal, B.; Margoni, M.; Marin, J.C.; Mariotti, C.; Markou, A.; Martinez-Rivero, C.; Masik, J.; Mastroyiannopoulos, N.; Matorras, F.; Matteuzzi, C.; Mazzucato, F.; Mazzucato, M.; McNulty, R.; Meroni, C.; Migliore, E.; Mitaroff, W.; Mjoernmark, U.; Moa, T.; Moch, M.; Monig, Klaus; Monge, R.; Montenegro, J.; Moraes, D.; Moreno, S.; Morettini, P.; Mueller, U.; Muenich, K.; Mulders, M.; Mundim, L.; Murray, W.; Muryn, B.; Myatt, G.; Myklebust, T.; Nassiakou, M.; Navarria, F.; Nawrocki, K.; Nicolaidou, R.; Nikolenko, M.; Oblakowska-Mucha, A.; Obraztsov, V.; Olshevski, A.; Onofre, A.; Orava, R.; Osterberg, K.; Ouraou, A.; Oyanguren, A.; Paganoni, M.; Paiano, S.; Palacios, J.P.; Palka, H.; Papadopoulou, Th.D.; Pape, L.; Parkes, C.; Parodi, F.; Parzefall, U.; Passeri, A.; Passon, O.; Peralta, L.; Perepelitsa, V.; Perrotta, A.; Petrolini, A.; Piedra, J.; Pieri, L.; Pierre, F.; Pimenta, M.; Piotto, E.; Podobnik, T.; Poireau, V.; Pol, M.E.; Polok, G.; Poropat, P.; Pozdniakov, V.; Pukhaeva, N.; Pullia, A.; Rames, J.; Ramler, L.; Read, Alexander L.; Rebecchi, P.; Rehn, J.; Reid, D.; Reinhardt, R.; Renton, P.; Richard, F.; Ridky, J.; Rivero, M.; Rodriguez, D.; Romero, A.; Ronchese, P.; Roudeau, P.; Rovelli, T.; Ruhlmann-Kleider, V.; Ryabtchikov, D.; Sadovsky, A.; Salmi, L.; Salt, J.; Savoy-Navarro, A.; Schwickerath, U.; Segar, A.; Sekulin, R.; Siebel, M.; Sisakian, A.; Smadja, G.; Smirnova, O.; Sokolov, A.; Sopczak, A.; Sosnowski, R.; Spassov, T.; Stanitzki, M.; Stocchi, A.; Strauss, J.; Stugu, B.; Szczekowski, M.; Szeptycka, M.; Szumlak, T.; Tabarelli, T.; Taffard, A.C.; Tegenfeldt, F.; Timmermans, Jan; Tkatchev, L.; Tobin, M.; Todorovova, S.; Tome, B.; Tonazzo, A.; Tortosa, P.; Travnicek, P.; Treille, D.; Tristram, G.; Trochimczuk, M.; Troncon, C.; Turluer, M.L.; Tyapkin, I.A.; Tyapkin, P.; Tzamarias, S.; Uvarov, V.; Valenti, G.; Van Dam, Piet; Van Eldik, J.; Van Lysebetten, A.; van Remortel, N.; Van Vulpen, I.; Vegni, G.; Veloso, F.; Venus, W.; Verdier, P.; Verzi, V.; Vilanova, D.; Vitale, L.; Vrba, V.; Wahlen, H.; Washbrook, A.J.; Weiser, C.; Wicke, D.; Wickens, J.; Wilkinson, G.; Winter, M.; Witek, M.; Yushchenko, O.; Zalewska, A.; Zalewski, P.; Zavrtanik, D.; Zhuravlov, V.; Zimine, N.I.; Zintchenko, A.; Zupan, M.

    2004-01-01

    A search for pair-produced charged Higgs bosons was performed in the data collected by the DELPHI detector at LEP II at centre-of-mass energies from 189 GeV to 209 GeV. Five different final states, tau+ nu_tau tau- anti-nu_tau, c sbar cbar s, c sbar tau- anti-nu_tau, W* A W* A and W* A tau- anti-nu_tau were considered, accounting for the major expected decays in type I and type II Two Higgs Doublet Models. No significant excess of data compared to the expected Standard Model processes was observed. The existence of a charged Higgs boson with mass lower than 76.7 GeV/c^2 (type I) or 74.4 GeV/c^2 (type II) is excluded at the 95% confidence level, for a wide range of the model parameters. Model independent cross-section limits have also been calculated.

  16. A new model for spherically symmetric charged compact stars of embedding class 1

    Energy Technology Data Exchange (ETDEWEB)

    Maurya, S.K. [University of Nizwa, Department of Mathematical and Physical Sciences, College of Arts and Science, Nizwa (Oman); Gupta, Y.K. [Raj Kumar Goel Institute of Technology, Department of Mathematics, Ghaziabad, U.P. (India); Ray, Saibal [Government College of Engineering and Ceramic Technology, Department of Physics, Kolkata, West Bengal (India); Deb, Debabrata [Indian Institute of Engineering Science and Technology, Department of Physics, Howrah, West Bengal (India)

    2017-01-15

    In the present study we search for a new stellar model with spherically symmetric matter and a charged distribution in a general relativistic framework. The model represents a compact star of embedding class 1. The solutions obtained here are general in nature, having the following two features: first of all, the metric becomes flat and also the expressions for the pressure, energy density, and electric charge become zero in all the cases if we consider the constant A = 0, which shows that our solutions represent the so-called 'electromagnetic mass model' [17], and, secondly, the metric function ν(r), for the limit n tending to infinity, converts to ν(r) = Cr{sup 2}+ ln B, which is the same as considered by Maurya et al. [11]. We have investigated several physical aspects of the model and find that all the features are acceptable within the requirements of contemporary theoretical studies and observational evidence. (orig.)

  17. The EV Project Price/Fee Models for Publicly Accessible Charging

    Energy Technology Data Exchange (ETDEWEB)

    Francfort, James Edward [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-12-01

    As plug-in electric vehicles (PEVs) are introduced to the market place and gain more consumer acceptance, it is important for a robust and self-sustaining non-residential infrastructure of electric vehicle supply equipment (EVSE) to be established to meet the needs of PEV drivers. While federal and state financial incentives for electric vehicles were in place and remain so today, future incentives are uncertain. In order for PEVs to achieve mainstream adoption, an adequate and sustainable commercial or publicly available charging infrastructure was pursued by The EV Project to encourage increased PEV purchases by alleviating range anxiety, and by removing adoption barriers for consumers without a dedicated overnight parking location to provide a home-base charger. This included determining a business model for publicly accessible charge infrastructure. To establish this business model, The EV Project team created a fee for charge model along with various ancillary offerings related to charging that would generate revenue. And after placing chargers in the field the Project rolled out this fee structure.

  18. Weather and Dispersion Modeling of the Fukushima Daiichi Nuclear Power Station Accident

    Science.gov (United States)

    Dunn, Thomas; Businger, Steven

    2014-05-01

    The surface deposition of radioactive material from the accident at the Fukushima Daiichi nuclear power station was investigated for 11 March to 17 March 2011. A coupled weather and dispersion modeling system was developed and simulations of the accident performed using two independent source terms that differed in emission rate and height and in the total amount of radioactive material released. Observations in Japan during the first week of the accident revealed a natural grouping between periods of dry (12-14 March) and wet (15-17 March) weather. The distinct weather regimes served as convenient validation periods for the model predictions. Results show significant differences in the distribution of cumulative surface deposition of 137Cs due to wet and dry removal processes. A comparison of 137Cs deposition predicted by the model with aircraft observations of surface-deposited gamma radiation showed reasonable agreement in surface contamination patterns during the dry phase of the accident for both source terms. It is suggested that this agreement is because of the weather model's ability to simulate the extent and timing of onshore flow associated with a sea breeze circulation that developed around the time of the first reactor explosion. During the wet phase of the accident the pattern is not as well predicted. It is suggested that this discrepancy is because of differences between model predicted and observed precipitation distributions.

  19. Evaluation of Radiation Components in a Global Freshwater Model with Station-Based Observations

    Directory of Open Access Journals (Sweden)

    Hannes Müller Schmied

    2016-10-01

    Full Text Available In many hydrological models, the amount of evapotranspired water is calculated using the potential evapotranspiration (PET approach. The main driver of several PET approaches is net radiation, whose downward components are usually obtained from meteorological input data, whereas the upward components are calculated by the model itself. Thus, uncertainties can be large due to both the input data and model assumptions. In this study, we compare the radiation components of the WaterGAP Global Hydrology Model, driven by two meteorological input datasets and two radiation setups from ERA-Interim reanalysis. We assess the performance with respect to monthly observations provided by the Baseline Surface Radiation Network (BSRN and the Global Energy Balance Archive (GEBA. The assessment is done for the global land area and specifically for energy/water limited regions. The results indicate that there is no optimal radiation input throughout the model variants, but standard meteorological input datasets perform better than those directly obtained by ERA-Interim reanalysis for the key variable net radiation. The low number of observations for some radiation components, as well as the scale mismatch between station observations and 0.5° × 0.5° grid cell size, limits the assessment.

  20. Looking For Physics Beyond The Standard Model: Searches For Charged Higgs Bosons At $e^{+}e^{-}$ Colliders

    CERN Document Server

    Kiiskinen, A P

    2004-01-01

    This thesis describes direct searches for pair production of charged Higgs bosons performed in the data collected by the DELPHI detector at the LEP collider at CERN. In addition, the possibilities to discover and study heavy charged Higgs bosons at possible future high-energy linear colliders are presented. The existence of charged Higgs bosons is predicted by many extensions of the Standard Model. A possible discovery of these particles would be a solid proof for physics beyond the Standard Model. Discovery of charged Higgs bosons, and measurement of their properties, would also provide useful information about the structure of the more general theory. New analysis methods were developed for the searches performed at LEP. A large, previously unexplored, mass range for cover but no evidence for the existence of the charged Higgs bosons was found. This allowed setting new lower mass limits for the charged Higgs boson within the framework of general two Higgs doublet models. Results have been interpreted and pr...

  1. Flocculation of Clay Colloids Induced by Model Polyelectrolytes: Effects of Relative Charge Density and Size.

    Science.gov (United States)

    Sakhawoth, Yasine; Michot, Laurent J; Levitz, Pierre; Malikova, Natalie

    2017-10-06

    Flocculation and its tuning are of utmost importance in the optimization of several industrial protocols in areas such as purification of waste water and civil engineering. Herein, we studied the polyelectrolyte-induced flocculation of clay colloids on a model system consisting of purified clay colloids of well-defined size fractions and ionene polyelectrolytes presenting regular and tunable chain charge density. To characterize ionene-induced clay flocculation, we turned to the combination of light absorbance (turbidity) and ζ-potential measurements, as well as adsorption isotherms. Our model system allowed us to identify the exact ratio of positive and negative charges in clay-ionene mixtures, the (c+/c-) ratio. For all samples studied, the onset of efficient flocculation occurred consistently at c+/c- ratios significantly below 1, which indicated the formation of highly ionene-deficient aggregates. At the same time, the ζ-potential measurements indicated an apparent zero charge on such aggregates. Thus, the ζ-potential values could not provide the stoichiometry inside the clay-ionene aggregates. The early onset of flocculation in clay-ionene mixtures is reminiscent of the behavior of multivalent salts and contrasts that of monovalent salts, for which a large excess amount of ions is necessary to achieve flocculation. Clear differences in the flocculation behavior are visible as a function of the ionene charge density, which governs the conformation of the ionene chains on the clay surface. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Charged black holes in a generalized scalar–tensor gravity model

    Directory of Open Access Journals (Sweden)

    Yves Brihaye

    2017-09-01

    Full Text Available We study 4-dimensional charged and static black holes in a generalized scalar–tensor gravity model, in which a shift symmetry for the scalar field exists. For vanishing scalar field the solution corresponds to the Reissner–Nordström (RN solution, while solutions of the full scalar-gravity model have to be constructed numerically. We demonstrate that these black holes support Galilean scalar hair up to a maximal value of the scalar–tensor coupling that depends on the value of the charge and can be up to roughly twice as large as that for uncharged solutions. The Hawking temperature TH of the hairy black holes at maximal scalar–tensor coupling decreases continuously with the increase of the charge and reaches TH=0 for the highest possible charge that these solutions can carry. However, in this limit, the scalar–tensor coupling needs to vanish. The limiting solution hence corresponds to the extremal RN solution, which does not support regular Galilean scalar hair due to its AdS2×S2 near-horizon geometry.

  3. Multiple-Trapping Model for the Charge Recombination Dynamics in Mesoporous-Structured Perovskite Solar Cells.

    Science.gov (United States)

    Wang, Hao-Yi; Wang, Yi; Hao, Ming-Yang; Qin, Yujun; Fu, Li-Min; Guo, Zhi-Xin; Ai, Xi-Cheng; Zhang, Jian-Ping

    2017-12-22

    The photovoltaic performance of organic-inorganic hybrid perovskite solar cells has reached a bottleneck after rapid development in last few years. Further breakthrough in this field requires deeper understanding of the underlying mechanism of the photoelectric conversion process in the device, especially the dynamics of charge-carrier recombination. Originating from dye-sensitized solar cells (DSSCs), mesoporous-structured perovskite solar cells (MPSCs) have shown many similarities to DSSCs with respect to their photoelectric dynamics. Herein, by applying the multiple-trapping model of the charge-recombination dynamic process for DSSCs in MPSCs, with rational modification, a novel physical model is proposed to describe the dynamics of charge recombination in MPSCs that exhibits good agreement with experimental data. Accordingly, the perovskite- and TiO 2 -dominating charge-recombination processes are assigned and their relationships with the trap-state distribution are also discussed. An optimal balance between these two dynamic processes is required to improve the performance of mesoporous-structured perovskite devices. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Charged black holes in a generalized scalar-tensor gravity model

    Science.gov (United States)

    Brihaye, Yves; Hartmann, Betti

    2017-09-01

    We study 4-dimensional charged and static black holes in a generalized scalar-tensor gravity model, in which a shift symmetry for the scalar field exists. For vanishing scalar field the solution corresponds to the Reissner-Nordström (RN) solution, while solutions of the full scalar-gravity model have to be constructed numerically. We demonstrate that these black holes support Galilean scalar hair up to a maximal value of the scalar-tensor coupling that depends on the value of the charge and can be up to roughly twice as large as that for uncharged solutions. The Hawking temperature TH of the hairy black holes at maximal scalar-tensor coupling decreases continuously with the increase of the charge and reaches TH = 0 for the highest possible charge that these solutions can carry. However, in this limit, the scalar-tensor coupling needs to vanish. The limiting solution hence corresponds to the extremal RN solution, which does not support regular Galilean scalar hair due to its AdS2 ×S2 near-horizon geometry.

  5. Exploring charge density analysis in crystals at high pressure: data collection, data analysis and advanced modelling.

    Science.gov (United States)

    Casati, Nicola; Genoni, Alessandro; Meyer, Benjamin; Krawczuk, Anna; Macchi, Piero

    2017-08-01

    The possibility to determine electron-density distribution in crystals has been an enormous breakthrough, stimulated by a favourable combination of equipment for X-ray and neutron diffraction at low temperature, by the development of simplified, though accurate, electron-density models refined from the experimental data and by the progress in charge density analysis often in combination with theoretical work. Many years after the first successful charge density determination and analysis, scientists face new challenges, for example: (i) determination of the finer details of the electron-density distribution in the atomic cores, (ii) simultaneous refinement of electron charge and spin density or (iii) measuring crystals under perturbation. In this context, the possibility of obtaining experimental charge density at high pressure has recently been demonstrated [Casati et al. (2016). Nat. Commun. 7, 10901]. This paper reports on the necessities and pitfalls of this new challenge, focusing on the species syn-1,6:8,13-biscarbonyl[14]annulene. The experimental requirements, the expected data quality and data corrections are discussed in detail, including warnings about possible shortcomings. At the same time, new modelling techniques are proposed, which could enable specific information to be extracted, from the limited and less accurate observations, like the degree of localization of double bonds, which is fundamental to the scientific case under examination.

  6. Observation of spatial charge and spin correlations in the 2D Fermi-Hubbard model.

    Science.gov (United States)

    Cheuk, Lawrence W; Nichols, Matthew A; Lawrence, Katherine R; Okan, Melih; Zhang, Hao; Khatami, Ehsan; Trivedi, Nandini; Paiva, Thereza; Rigol, Marcos; Zwierlein, Martin W

    2016-09-16

    Strong electron correlations lie at the origin of high-temperature superconductivity. Its essence is believed to be captured by the Fermi-Hubbard model of repulsively interacting fermions on a lattice. Here we report on the site-resolved observation of charge and spin correlations in the two-dimensional (2D) Fermi-Hubbard model realized with ultracold atoms. Antiferromagnetic spin correlations are maximal at half-filling and weaken monotonically upon doping. At large doping, nearest-neighbor correlations between singly charged sites are negative, revealing the formation of a correlation hole, the suppressed probability of finding two fermions near each other. As the doping is reduced, the correlations become positive, signaling strong bunching of doublons and holes, in agreement with numerical calculations. The dynamics of the doublon-hole correlations should play an important role for transport in the Fermi-Hubbard model. Copyright © 2016, American Association for the Advancement of Science.

  7. A unified analytical model for charge transport in Heterojunction Bipolar Transistors

    Science.gov (United States)

    Venkateswara Reddy, K.; DasGupta, Amitava

    2004-09-01

    A unified analytical charge transport model of HBTs, which is applicable for a wide variety of emitter-base (e-b) structures of HBTs, viz. abrupt or graded heterojunctions and p-n junctions displaced into wider or narrower band gap material is proposed. This is a thermionic field diffusion model, which considers thermionic emission and tunneling at the e-b heterojunction and diffusion in the quasi-neutral base regions. The Fermi-level splitting is considered while calculating the space charge region (SCR) recombination currents, which in turn is taken into account to calculate excess electron concentration at the edge of the depletion region in the base side of the e-b p-n junction. Closed form analytical expressions for the terminal currents are obtained, which has been implemented in a circuit simulator. The accuracy of the model is established by comparison with numerical simulation results and experimental data.

  8. A numerical model for charge transport and energy conversion of perovskite solar cells.

    Science.gov (United States)

    Zhou, Yecheng; Gray-Weale, Angus

    2016-02-14

    Based on the continuity equations and Poisson's equation, we developed a numerical model for perovskite solar cells. Due to different working mechanisms, the model for perovskite solar cells differs from that of silicon solar cells and Dye Sensitized Solar Cells. The output voltage and current are calculated differently, and in a manner suited in particular to perovskite organohalides. We report a test of our equations against experiment with good agreement. Using this numerical model, it was found that performances of solar cells increase with charge carrier's lifetimes, mobilities and diffusion lengths. The open circuit voltage (Voc) of a solar cell is dependent on light intensities, and charge carrier lifetimes. Diffusion length and light intensity determine the saturated current (Jsc). Additionally, three possible guidelines for the design and fabrication of perovskite solar cells are suggested by our calculations. Lastly, we argue that concentrator perovskite solar cells are promising.

  9. Neutrino Masses and Lepton-Flavor Violation in Supersymmetric Models with lopsided Froggatt-Nielsen charges

    CERN Document Server

    Sato, J; Sato, Joe; Tobe, Kazuhiro

    2001-01-01

    We analyze in detail lepton-flavor violation (LFV) in the charged-lepton sector such as $\\mu \\to e \\gamma$, $\\tau \\to \\mu \\gamma$, $\\mu \\to eee$ and the $\\mu \\to e$ conversion in nuclei, within the framework of supersymmetric models with lopsided Froggatt--Nielsen charges, in which the large mixing in the neutrino sector as well as small mixings in the quark sector can be naturally accommodated. We show that the present experimental limits on the LFV processes already exclude some of the models. The future proposed search for LFV, especially in muon processes, can provide a significant probe to this framework. We also stress the importance of the measurement of $U^{MNS}_{e3}$ in neutrino experiments, and the fact that the KamLAND experiment could play a significant role to test a certain class of models.

  10. The Channel Estimation and Modeling in High Altitude Platform Station Wireless Communication Dynamic Network

    Directory of Open Access Journals (Sweden)

    Xiaoyang Liu

    2017-01-01

    Full Text Available In order to analyze the channel estimation performance of near space high altitude platform station (HAPS in wireless communication system, the structure and formation of HAPS are studied in this paper. The traditional Least Squares (LS channel estimation method and Singular Value Decomposition-Linear Minimum Mean-Squared (SVD-LMMS channel estimation method are compared and investigated. A novel channel estimation method and model are proposed. The channel estimation performance of HAPS is studied deeply. The simulation and theoretical analysis results show that the performance of the proposed method is better than the traditional methods. The lower Bit Error Rate (BER and higher Signal Noise Ratio (SNR can be obtained by the proposed method compared with the LS and SVD-LMMS methods.

  11. Comparison of steel desulphurisation at homogenisation station with physical modelling results

    Directory of Open Access Journals (Sweden)

    L. Socha

    2015-10-01

    Full Text Available The paper deals with evaluation of relevant information about transfer processes taking place in the interface slag – metal and with the assessment of the rate and course of steel desulphurization. The study of mentioned processes took place with the verification of the results obtained by the plant experiments in the homogenization station using 180 t ladle and in the physical model of the ladle in the geometrical scale 1 : 9 supplemented by homogenization nozzle. Plant and physical experiments were based on similar methodology. Samples of metal and slag were taken in regular time intervals for following evaluation of kinetics of the sulphur loss in the metal and appropriate increase of sulphur contain in the slag.

  12. A generalized multi-dimensional mathematical model for charging and discharging processes in a supercapacitor

    Energy Technology Data Exchange (ETDEWEB)

    Allu, Srikanth [ORNL; Velamur Asokan, Badri [Exxon Mobil Research and Engineering; Shelton, William A [Louisiana State University; Philip, Bobby [ORNL; Pannala, Sreekanth [ORNL

    2014-01-01

    A generalized three dimensional computational model based on unied formulation of electrode- electrolyte-electrode system of a electric double layer supercapacitor has been developed. The model accounts for charge transport across the solid-liquid system. This formulation based on volume averaging process is a widely used concept for the multiphase ow equations ([28] [36]) and is analogous to porous media theory typically employed for electrochemical systems [22] [39] [12]. This formulation is extended to the electrochemical equations for a supercapacitor in a consistent fashion, which allows for a single-domain approach with no need for explicit interfacial boundary conditions as previously employed ([38]). In this model it is easy to introduce the spatio-temporal variations, anisotropies of physical properties and it is also conducive for introducing any upscaled parameters from lower length{scale simulations and experiments. Due to the irregular geometric congurations including porous electrode, the charge transport and subsequent performance characteristics of the super-capacitor can be easily captured in higher dimensions. A generalized model of this nature also provides insight into the applicability of 1D models ([38]) and where multidimensional eects need to be considered. In addition, simple sensitivity analysis on key input parameters is performed in order to ascertain the dependence of the charge and discharge processes on these parameters. Finally, we demonstarted how this new formulation can be applied to non-planar supercapacitors

  13. Translocation of positively and negatively charged polystyrene nanoparticles in an in vitro placental model.

    Science.gov (United States)

    Kloet, Samantha K; Walczak, Agata P; Louisse, Jochem; van den Berg, Hans H J; Bouwmeester, Hans; Tromp, Peter; Fokkink, Remco G; Rietjens, Ivonne M C M

    2015-10-01

    To obtain insight in translocation of nanoparticles across the placental barrier, translocation was studied for one positively and two negatively charged polystyrene nanoparticles (PS-NPs) of similar size in an in vitro model. The model consisted of BeWo b30 cells, derived from a human choriocarcinoma grown on a transwell insert forming a cell layer that separates an apical from a basolateral compartment. PS-NPs were characterized with respect to size, surface charge, morphology and protein corona. Translocation of PS-NPs was not related to PS-NP charge. Two PS-NPs were translocated across the BeWo transwell model to a lower extent than amoxicillin, a model compound known to be translocated over the placental barrier to only a limited extent, whereas one PS-NP showed a slightly higher translocation. Studies on the effect of transporter inhibitors on the translocation of the PS-NPs indicated that their translocation was not mediated by known transporters and mainly dependent on passive diffusion. It is concluded that the BeWo b30 model can be used as an efficient method to get an initial qualitative impression about the capacity of NPs to translocate across the placental barrier and set priorities in further in vivo studies on translocation of NPs to the fetus. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Optimal Facility Location Model Based on Genetic Simulated Annealing Algorithm for Siting Urban Refueling Stations

    Directory of Open Access Journals (Sweden)

    Dawei Chen

    2015-01-01

    Full Text Available This paper analyzes the impact factors and principles of siting urban refueling stations and proposes a three-stage method. The main objective of the method is to minimize refueling vehicles’ detour time. The first stage aims at identifying the most frequently traveled road segments for siting refueling stations. The second stage focuses on adding additional refueling stations to serve vehicles whose demands are not directly satisfied by the refueling stations identified in the first stage. The last stage further adjusts and optimizes the refueling station plan generated by the first two stages. A genetic simulated annealing algorithm is proposed to solve the optimization problem in the second stage and the results are compared to those from the genetic algorithm. A case study is also conducted to demonstrate the effectiveness of the proposed method and algorithm. The results indicate the proposed method can provide practical and effective solutions that help planners and government agencies make informed refueling station location decisions.

  15. Quantum phase diagram of the half filled Hubbard model with bond-charge interaction

    Energy Technology Data Exchange (ETDEWEB)

    Dobry, A.O., E-mail: dobry@ifir-conicet.gov.a [Facultad de Ciencias Exactas Ingenieria y Agrimensura, Universidad Nacional de Rosario and Instituto de Fisica Rosario, Bv. 27 de Febrero 210 bis, 2000 Rosario (Argentina); Aligia, A.A. [Centro Atomico Bariloche and Instituto Balseiro, Comision Nacional de Energia Atomica, 8400 Bariloche (Argentina)

    2011-02-21

    Using quantum field theory and bosonization, we determine the quantum phase diagram of the one-dimensional Hubbard model with bond-charge interaction X in addition to the usual Coulomb repulsion U at half-filling, for small values of the interactions. We show that it is essential to take into account formally irrelevant terms of order X. They generate relevant terms proportional to X{sup 2} in the flow of the renormalization group (RG). These terms are calculated using operator product expansions. The model shows three phases separated by a charge transition at U=U{sub c} and a spin transition at U=U{sub s}>U{sub c}. For UU{sub s}, the system is in the spin-density wave phase as in the usual Hubbard model. For intermediate values U{sub c}model with X=0. We obtain that the charge transition remains at U{sub c}=0 for X{ne}0. Solving the RG equations for the spin sector, we provide an analytical expression for U{sub s}(X). The results, with only one adjustable parameter, are in excellent agreement with numerical ones for X

  16. A STRONGLY COUPLED REACTOR CORE ISOLATION COOLING SYSTEM MODEL FOR EXTENDED STATION BLACK-OUT ANALYSES

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Haihua [Idaho National Laboratory; Zhang, Hongbin [Idaho National Laboratory; Zou, Ling [Idaho National Laboratory; Martineau, Richard Charles [Idaho National Laboratory

    2015-03-01

    The reactor core isolation cooling (RCIC) system in a boiling water reactor (BWR) provides makeup cooling water to the reactor pressure vessel (RPV) when the main steam lines are isolated and the normal supply of water to the reactor vessel is lost. The RCIC system operates independently of AC power, service air, or external cooling water systems. The only required external energy source is from the battery to maintain the logic circuits to control the opening and/or closure of valves in the RCIC systems in order to control the RPV water level by shutting down the RCIC pump to avoid overfilling the RPV and flooding the steam line to the RCIC turbine. It is generally considered in almost all the existing station black-out accidents (SBO) analyses that loss of the DC power would result in overfilling the steam line and allowing liquid water to flow into the RCIC turbine, where it is assumed that the turbine would then be disabled. This behavior, however, was not observed in the Fukushima Daiichi accidents, where the Unit 2 RCIC functioned without DC power for nearly three days. Therefore, more detailed mechanistic models for RCIC system components are needed to understand the extended SBO for BWRs. As part of the effort to develop the next generation reactor system safety analysis code RELAP-7, we have developed a strongly coupled RCIC system model, which consists of a turbine model, a pump model, a check valve model, a wet well model, and their coupling models. Unlike the traditional SBO simulations where mass flow rates are typically given in the input file through time dependent functions, the real mass flow rates through the turbine and the pump loops in our model are dynamically calculated according to conservation laws and turbine/pump operation curves. A simplified SBO demonstration RELAP-7 model with this RCIC model has been successfully developed. The demonstration model includes the major components for the primary system of a BWR, as well as the safety

  17. Finite field methods for the supercell modeling of charged insulator/electrolyte interfaces

    Science.gov (United States)

    Zhang, Chao; Sprik, Michiel

    2016-12-01

    Surfaces of ionic solids interacting with an ionic solution can build up charge by exchange of ions. The surface charge is compensated by a strip of excess charge at the border of the electrolyte forming an electric double layer. These electric double layers are very hard to model using the supercell's methods of computational condensed phase science. The problem arises when the solid is an electric insulator (as most ionic solids are) permitting a finite interior electric field over the width of the slab representing the solid in the supercell. The slab acts as a capacitor. The stored charge is a deficit in the solution failing to compensate fully for the solid surface charge. Here, we show how these problems can be overcome using the finite field methods developed by Stengel, Spaldin, and Vanderbilt [Nat. Phys. 5, 304 (2009), 10.1038/nphys1185]. We also show how the capacitance of the double layer can be computed once overall electric neutrality of the double layer is restored by application of a finite macroscopic field E or alternatively by zero electric displacement D . The method is validated for a classical model of a solid-electrolyte interface using the finite-temperature molecular dynamics adaptation of the constant field method presented previously [C. Zhang and M. Sprik, Phys. Rev. B 93, 144201 (2016), 10.1103/PhysRevB.93.144201]. Because ions in electrolytes can diffuse across supercell boundaries, this application turns out to be a critical illustration of the multivaluedness of polarization in periodic systems.

  18. Use of Human Computer Models to Influence the Design of International Space Station Propulsion Module

    Science.gov (United States)

    Hamilton, George S.; Hall, Meridith L.

    1999-01-01

    The overall design for the International Space Station (ISS) Propulsion (Prop) Module consists of two bell shapes connected by a long tube having a shirt sleeve environment. The tube is to be used by the flight crew to transfer equipment and supplies from the Shuttle to ISS. Due to a desire to use existing space qualified hardware, the tube internal diameter was initially set at 38 inches, while the human engineering specification, NASA-STD-3000, required 50". Human computer modeling using the MannequinPro application was used to help make the case to enlarge the passageway to meet the specification. 3D CAD models of Prop Module were created with 38 inches, 45 inches and 50 inches passageways and human figures in the neutral body posture as well as a fetal posture were inserted into the model and systematically exercised. Results showed that only the 50 inches tube would accommodate a mid tube turn around by a large crew member, 95th percentile American males, by stature.

  19. International Space Station Human Behavior and Performance Competency Model: Volume I

    Science.gov (United States)

    Schmidt, Lacey

    2008-01-01

    This document defines Human Behavior and Performance (HBP) competencies that are recommended to be included as requirements to participate in international long duration missions. They were developed in response to the Multilateral Crew Operations Panel (MMOP) request to develop HBP training requirements for the International Space Station (ISS). The competency model presented here was developed by the ITCB HBPT WG and forms the basis for determining the HBP training curriculum for long duration crewmembers. This document lists specific HBP competencies and behaviors required of astronauts/cosmonauts who participate in ISS expedition and other international longduration missions. Please note that this model does not encompass all competencies required. For example, outside the scope of this document are cognitive skills and abilities, including but not limited to concentration, memorization, perception, imagination, and thinking. It is assumed that these skills, which are crucial in terms of human behavior and performance, are considered during selection phase since such professionally significant qualities of the operator should be taken into consideration in order to ensure sufficient baseline levels that can be further improved during general astronaut training. Also, technical competencies, even though critical for crewmembers, are beyond the scope of this document. It should also be noted that the competencies in this model (and subsequent objectives) are not intended to limit the internal activities or training programs of any international partner.

  20. Modeling Woody Biomass Procurement for Bioenergy Production at the Atikokan Generating Station in Northwestern Ontario, Canada

    Directory of Open Access Journals (Sweden)

    Thakur Upadhyay

    2012-12-01

    Full Text Available Efficient procurement and utilization of woody biomass for bioenergy production requires a good understanding of biomass supply chains. In this paper, a dynamic optimization model has been developed and applied to estimate monthly supply and procurement costs of woody biomass required for the Atikokan Generating Station (AGS in northwestern Ontario, based on its monthly electricity production schedule. The decision variables in the model are monthly harvest levels of two types of woody biomass, forest harvest residues and unutilized biomass, from 19,315 forest depletion cells (each 1 km2 for a one year planning horizon. Sixteen scenarios are tested to examine the sensitivity of the cost minimization model to changing economic and technological parameters. Reduction in moisture content and improvement of conversion efficiency showed relatively higher reductions in monthly and total costs of woody biomass feedstock for the AGS. The results of this study help in understanding and designing decision support systems for optimal biomass supply chains under dynamic operational frameworks.

  1. Breadboard model of the SIDRA instrument designed for the measurement of charged particle fluxes in space

    Science.gov (United States)

    Prieto, M.; Dudnik, O. V.; Sanchez, S.; Kurbatov, E. V.; Timakova, T. G.; Tejedor, J. I. G.; Titov, K. G.

    2013-04-01

    This report delves into the concept of the SIDRA instrument designed for the measurement of energetic fluxes of charged particles in space. It also presents the preliminary laboratory tests results of the breadboard model electronic units. The SIDRA instrument consists of a detector head made of high purity silicon and high performance scintillation detectors, analog and digital signal processing units, and it also includes a secondary power supply module. Preliminary results of Monte Carlo instrument simulation using the CERN GEANT4 tool are presented and the measured key specifications of charge-to-voltage converters, shapers and peak detectors are discussed. Finally, the performance of the digital processing unit with its software and the parameters of the instrument breadboard model, in particular mass, dimensions and power consumption are also presented.

  2. An electric vehicle driving behavior model in the traffic system with a wireless charging lane

    Science.gov (United States)

    He, Jia; Huang, Hai-Jun; Yang, Hai; Tang, Tie-Qiao

    2017-09-01

    In this paper, a car-following model is proposed to study each EV's (electric vehicle) motion behavior near the WCL (wireless charging lane) and a lane-changing rule is designed to describe the EV's lane-changing behavior. Then, the car-following model and lane-changing rule are used to explore each EV's micro driving behavior in a two-lane system with a WCL. Finally, the impacts of the WCL on each EV's motion behavior are investigated. The numerical results show that each EV should run slowly on the WCL if it needs charge of electricity, that the EV's lane-changing behavior has great effects on the whole system, that the delay time caused by the WCL turns more prominent when the traffic turns heavy, and that lane-changing frequently occurs near the WCL (especially at the downstream of the WCL).

  3. Magnetically charged regular black hole in a model of nonlinear electrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Meng-Sen, E-mail: mengsenma@gmail.com

    2015-11-15

    We obtain a magnetically charged regular black hole in general relativity. The source to the Einstein field equations is nonlinear electrodynamic field in a physically reasonable model of nonlinear electrodynamics (NED). “Physically” here means the NED model is constructed on the basis of three conditions: the Maxwell asymptotic in the weak electromagnetic field limit; the presence of vacuum birefringence phenomenon; and satisfying the weak energy condition (WEC). In addition, we analyze the thermodynamic properties of the regular black hole in two ways. According to the usual black hole thermodynamics, we calculate the heat capacity at constant charge, from which we know the smaller black hole is more stable. We also employ the horizon thermodynamics to discuss the thermodynamic quantities, especially the heat capacity at constant pressure.

  4. Stochastic-hydrodynamic model of halo formation in charged particle beams

    Directory of Open Access Journals (Sweden)

    Nicola Cufaro Petroni

    2003-03-01

    Full Text Available The formation of the beam halo in charged particle accelerators is studied in the framework of a stochastic-hydrodynamic model for the collective motion of the particle beam. In such a stochastic-hydrodynamic theory the density and the phase of the charged beam obey a set of coupled nonlinear hydrodynamic equations with explicit time-reversal invariance. This leads to a linearized theory that describes the collective dynamics of the beam in terms of a classical Schrödinger equation. Taking into account space-charge effects, we derive a set of coupled nonlinear hydrodynamic equations. These equations define a collective dynamics of self-interacting systems much in the same spirit as in the Gross-Pitaevskii and Landau-Ginzburg theories of the collective dynamics for interacting quantum many-body systems. Self-consistent solutions of the dynamical equations lead to quasistationary beam configurations with enhanced transverse dispersion and transverse emittance growth. In the limit of a frozen space-charge core it is then possible to determine and study the properties of stationary, stable core-plus-halo beam distributions. In this scheme the possible reproduction of the halo after its elimination is a consequence of the stationarity of the transverse distribution which plays the role of an attractor for every other distribution.

  5. Modeling of direct beam extraction for a high-charge-state fusion driver

    Science.gov (United States)

    Anderson, O. A.; Grant Logan, B.

    A newly proposed type of multicharged ion source offers the possibility of an economically advantageous high-charge-state fusion driver. Multiphoton absorption in an intense uniform laser focus can give multiple charge states of high purity, simplifying or eliminating the need for charge-state separation downstream. Very large currents (hundreds of amperes) can be extracted from this type of source. Several arrangements are possible. For example, the laser plasma could be tailored for storage in a magnetic bucket, with beam extracted from the bucket. A different approach, described in this report, is direct beam extraction from the expanding laser plasma. We discuss extraction and focusing for the particular case of a 4.1 MV beam of Xe 16+ ions. The maximum duration of the beam pulse is limited by the total charge in the plasma, while the practical pulse length is determined by the range of plasma radii over which good beam optics can be achieved. The extraction electrode contains a solenoid for beam focusing. Our design studies were carried out first with an envelope code and then with a self-consistent particle code. Results from our initial model showed that hundreds of amperes could be extracted, but that most of this current missed the solenoid entrance or was intercepted by the wall and that only a few amperes were able to pass through. We conclude with an improved design which increases the surviving beam to more than 70 A.

  6. Charged patchy particle models in explicit salt: Ion distributions, electrostatic potentials, and effective interactions.

    Science.gov (United States)

    Yigit, Cemil; Heyda, Jan; Dzubiella, Joachim

    2015-08-14

    We introduce a set of charged patchy particle models (CPPMs) in order to systematically study the influence of electrostatic charge patchiness and multipolarity on macromolecular interactions by means of implicit-solvent, explicit-ion Langevin dynamics simulations employing the Gromacs software. We consider well-defined zero-, one-, and two-patched spherical globules each of the same net charge and (nanometer) size which are composed of discrete atoms. The studied mono- and multipole moments of the CPPMs are comparable to those of globular proteins with similar size. We first characterize ion distributions and electrostatic potentials around a single CPPM. Although angle-resolved radial distribution functions reveal the expected local accumulation and depletion of counter- and co-ions around the patches, respectively, the orientation-averaged electrostatic potential shows only a small variation among the various CPPMs due to space charge cancellations. Furthermore, we study the orientation-averaged potential of mean force (PMF), the number of accumulated ions on the patches, as well as the CPPM orientations along the center-to-center distance of a pair of CPPMs. We compare the PMFs to the classical Derjaguin-Verwey-Landau-Overbeek theory and previously introduced orientation-averaged Debye-Hückel pair potentials including dipolar interactions. Our simulations confirm the adequacy of the theories in their respective regimes of validity, while low salt concentrations and large multipolar interactions remain a challenge for tractable theoretical descriptions.

  7. Charged patchy particle models in explicit salt: Ion distributions, electrostatic potentials, and effective interactions

    Energy Technology Data Exchange (ETDEWEB)

    Yigit, Cemil; Dzubiella, Joachim, E-mail: joachim.dzubiella@helmholtz-berlin.de [Soft Matter and Functional Materials, Helmholtz-Zentrum Berlin, 14109 Berlin (Germany); Helmholtz Virtual Institute “Multifunctional Biomaterials for Medicine,” 14513 Teltow (Germany); Institut für Physik, Humboldt-Universität zu Berlin, 12489 Berlin (Germany); Heyda, Jan [Department of Physical Chemistry, University of Chemistry and Technology, Prague, 166 28 Praha 6 (Czech Republic)

    2015-08-14

    We introduce a set of charged patchy particle models (CPPMs) in order to systematically study the influence of electrostatic charge patchiness and multipolarity on macromolecular interactions by means of implicit-solvent, explicit-ion Langevin dynamics simulations employing the Gromacs software. We consider well-defined zero-, one-, and two-patched spherical globules each of the same net charge and (nanometer) size which are composed of discrete atoms. The studied mono- and multipole moments of the CPPMs are comparable to those of globular proteins with similar size. We first characterize ion distributions and electrostatic potentials around a single CPPM. Although angle-resolved radial distribution functions reveal the expected local accumulation and depletion of counter- and co-ions around the patches, respectively, the orientation-averaged electrostatic potential shows only a small variation among the various CPPMs due to space charge cancellations. Furthermore, we study the orientation-averaged potential of mean force (PMF), the number of accumulated ions on the patches, as well as the CPPM orientations along the center-to-center distance of a pair of CPPMs. We compare the PMFs to the classical Derjaguin-Verwey-Landau-Overbeek theory and previously introduced orientation-averaged Debye-Hückel pair potentials including dipolar interactions. Our simulations confirm the adequacy of the theories in their respective regimes of validity, while low salt concentrations and large multipolar interactions remain a challenge for tractable theoretical descriptions.

  8. A Boltzmann-weighted hopping model of charge transport in organic semicrystalline films

    KAUST Repository

    Kwiatkowski, Joe J.

    2011-01-01

    We present a model of charge transport in polycrystalline electronic films, which considers details of the microscopic scale while simultaneously allowing realistically sized films to be simulated. We discuss the approximations and assumptions made by the model, and rationalize its application to thin films of directionally crystallized poly(3-hexylthiophene). In conjunction with experimental data, we use the model to characterize the effects of defects in these films. Our findings support the hypothesis that it is the directional crystallization of these films, rather than their defects, which causes anisotropic mobilities. © 2011 American Institute of Physics.

  9. Charge and spin current statistics of the open Hubbard model with weak coupling to the environment.

    Science.gov (United States)

    Buča, Berislav; Prosen, Tomaž

    2017-05-01

    Based on generalization and extension of our previous work [Phys. Rev. Lett. 112, 067201 (2014)PRLTAO0031-900710.1103/PhysRevLett.112.067201] to multiple independent Markovian baths we will compute the charge and spin current statistics of the open Hubbard model with weak system-bath coupling up to next-to-leading order in the coupling parameter. Only the next-to-leading and higher orders depend on the Hubbard interaction parameter. The physical results are related to those for the XXZ model in the analogous setup implying a certain universality, which potentially holds in this class of nonequilibrium models.

  10. Biquaternionic Model of Electro-Gravimagnetic Field, Charges and Currents. Law of Inertia

    CERN Document Server

    Alexeyeva, Lyudmila

    2016-01-01

    One the base of Maxwell and Dirac equations the one biquaternionic model of electro-gravimagnetic (EGM) fields is considered. The closed system of biquaternionic wave equations is constructed for determination of free system of electric and gravimagnetic charges and currents and generated by them EGM-field. By using generalized functions theory the fundamental and regular solutions of this system are determined and some of them are considered (spinors, plane waves, shock EGMwaves and others). The properties of these solutions are investigated.

  11. A zero dimensional model of lithium-sulfur batteries during charge and discharge.

    Science.gov (United States)

    Marinescu, Monica; Zhang, Teng; Offer, Gregory J

    2016-01-07

    Lithium-sulfur cells present an attractive alternative to Li-ion batteries due to their large energy density, safety, and possible low cost. Their successful commercialisation is dependent on improving their performance, but also on acquiring sufficient understanding of the underlying mechanisms to allow for the development of predictive models for operational cells. To address the latter, we present a zero dimensional model that predicts many of the features observed in the behaviour of a lithium-sulfur cell during charge and discharge. The model accounts for two electrochemical reactions via the Nernst formulation, power limitations through Butler-Volmer kinetics, and precipitation/dissolution of one species, including nucleation. It is shown that the flat shape of the low voltage plateau typical of the lithium-sulfur cell discharge is caused by precipitation. During charge, it is predicted that the dissolution can act as a bottleneck, because for large enough currents the amount that dissolves becomes limited. This results in reduced charge capacity and an earlier onset of the high plateau reaction, such that the two voltage plateaus merge. By including these effects, the model improves on the existing zero dimensional models, while requiring considerably fewer input parameters and computational resources than one dimensional models. The model also predicts that, due to precipitation, the customary way of experimentally obtaining the open circuit voltage from a low rate discharge might not be suitable for lithium-sulfur. This model can provide the basis for mechanistic studies, identification of dominant effects in a real cell, predictions of operational behaviour under realistic loads, and control algorithms for applications.

  12. A hybrid, coupled approach for modeling charged fluids from the nano to the mesoscale

    Science.gov (United States)

    Cheung, James; Frischknecht, Amalie L.; Perego, Mauro; Bochev, Pavel

    2017-11-01

    We develop and demonstrate a new, hybrid simulation approach for charged fluids, which combines the accuracy of the nonlocal, classical density functional theory (cDFT) with the efficiency of the Poisson-Nernst-Planck (PNP) equations. The approach is motivated by the fact that the more accurate description of the physics in the cDFT model is required only near the charged surfaces, while away from these regions the PNP equations provide an acceptable representation of the ionic system. We formulate the hybrid approach in two stages. The first stage defines a coupled hybrid model in which the PNP and cDFT equations act independently on two overlapping domains, subject to suitable interface coupling conditions. At the second stage we apply the principles of the alternating Schwarz method to the hybrid model by using the interface conditions to define the appropriate boundary conditions and volume constraints exchanged between the PNP and the cDFT subdomains. Numerical examples with two representative examples of ionic systems demonstrate the numerical properties of the method and its potential to reduce the computational cost of a full cDFT calculation, while retaining the accuracy of the latter near the charged surfaces.

  13. Comments on central charge of topological sigma model with Calabi-Yau target space

    Energy Technology Data Exchange (ETDEWEB)

    Sugiyama, Katsuyuki E-mail: sugiyama@phys.h.kyoto-u.ac.jp

    2000-12-25

    We study a central charge Z of a one parameter family of Calabi-Yau d-fold embedded in CP{sup d+1}. For a d-fold case, we construct the Z concretely and analyze charge vectors of D-branes and intersection forms of associated cycles. We find the charges are described as some kinds of Mukai vectors. They are represented as products of Chern characters of coherent sheaves restricted on the Calabi-Yau hypersurfaces and square roots of A-roof genera of the d-folds. By combining results of the topological sigma model and the data of the CFT calculations in the Gepner model, we find that the Z is determined and is specified by a set of integers that labels boundary states in special classes where associated states are represented as tensor products of boundary states for constituent minimal models. The Z has a moduli parameter 't' that describes a deformation of a moduli space in the open string channel with B-type boundary conditions. Also monodromy matrices and homology cycles are investigated.

  14. Charge and spin quantum fluctuations in the doped strongly coupled Hubbard model on the honeycomb lattice

    Science.gov (United States)

    Ribeiro, F. G.; Coutinho-Filho, M. D.

    2015-07-01

    Field-theoretic methods are used to investigate the large-U Hubbard model on the honeycomb lattice at half-filling and in the hole-doped regime. Within the framework of a functional-integral approach, we obtain the Lagrangian density associated with the charge and spin degrees of freedom. The Hamiltonian related to the charge degrees of freedom is exactly diagonalized. In the strong-coupling regime, we derive a perturbative low-energy theory suitable to describe the quantum antiferromagnetic phase (AF) as a function of hole doping. At half-filling, we deal with the underlying spin degrees of freedom of the quantum AF Heisenberg model by employing a second-order spin-wave analysis, in which case we have calculated the ground-state energy and the staggered magnetization; the results are in very good agreement with previous studies. Further, in the continuum, we derive a nonlinear σ model with a topological Hopf term that describes the AF-VBS (valence bond solid) competition. Lastly, in the challenging doped regime, our approach allows the derivation of a t -J Hamiltonian, and the analysis of the role played by charge and spin quantum fluctuations on the ground-state energy and, particularly, on the breakdown of the AF order at a critical hole doping; the results are benchmarked against recent Grassmann tensor product state simulations.

  15. A stepped leader model for lightning including charge distribution in branched channels

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Wei; Zhang, Li [School of Electrical Engineering, Shandong University, Jinan 250061 (China); Li, Qingmin, E-mail: lqmeee@ncepu.edu.cn [Beijing Key Lab of HV and EMC, North China Electric Power University, Beijing 102206 (China); State Key Lab of Alternate Electrical Power System with Renewable Energy Sources, Beijing 102206 (China)

    2014-09-14

    The stepped leader process in negative cloud-to-ground lightning plays a vital role in lightning protection analysis. As lightning discharge usually presents significant branched or tortuous channels, the charge distribution along the branched channels and the stochastic feature of stepped leader propagation were investigated in this paper. The charge density along the leader channel and the charge in the leader tip for each lightning branch were approximated by introducing branch correlation coefficients. In combination with geometric characteristics of natural lightning discharge, a stochastic stepped leader propagation model was presented based on the fractal theory. By comparing simulation results with the statistics of natural lightning discharges, it was found that the fractal dimension of lightning trajectory in simulation was in the range of that observed in nature and the calculation results of electric field at ground level were in good agreement with the measurements of a negative flash, which shows the validity of this proposed model. Furthermore, a new equation to estimate the lightning striking distance to flat ground was suggested based on the present model. The striking distance obtained by this new equation is smaller than the value estimated by previous equations, which indicates that the traditional equations may somewhat overestimate the attractive effect of the ground.

  16. Modeled contributions of three types of diazotrophs to nitrogen fixation at Station ALOHA.

    Science.gov (United States)

    Goebel, Nicole L; Edwards, Christopher A; Church, Matthew J; Zehr, Jonathan P

    2007-11-01

    A diagnostic model based on biomass and growth was used to assess the relative contributions of filamentous nonheterocystous Trichodesmium and unicellular cyanobacteria, termed Groups A and B, to nitrogen fixation at the North Pacific Station ALOHA over a 2-year period. Average (and 95% confidence interval, CI) annual rates of modeled monthly values for Trichodesmium, Group B and Group A were 92 (52), 14 (4) and 12 (8) mmol N per m(2) per year, respectively. The fractional contribution to modeled instantaneous nitrogen fixation by each diazotroph fluctuated on interannual, seasonal and shorter time scales. Trichodesmium fixed substantially more nitrogen in year 1 (162) than year 2 (12). Group B fixed almost two times more nitrogen in year 1 (17) than year 2 (9). In contrast, Group A fixed two times more nitrogen in year 2 (16) than year 1 (8). When including uncertainties in our estimates using the bootstrap approach, the range of unicellular nitrogen fixation extended from 10% to 68% of the total annual rate of nitrogen fixation for all three diazotrophs. Furthermore, on a seasonal basis, the model demonstrated that unicellular diazotrophs fixed the majority (51%-97%) of nitrogen during winter and spring, whereas Trichodesmium dominated nitrogen fixation during summer and autumn (60%-96%). Sensitivity of the modeled rates to some parameters suggests that this unique attempt to quantify relative rates of nitrogen fixation by different diazotrophs may need to be reevaluated as additional information on cell size, variability in biomass and C:N, and growth characteristics of the different cyanobacterial diazotrophs become available.

  17. Evaluating the Impact of the Summit Station, Greenland Radiosonde Program on Data Modelers and Forecast Services

    Science.gov (United States)

    Martinez, C. J.; Starkweather, S.; Cox, C. J.; Solomon, A.; Shupe, M.

    2015-12-01

    Radiosondes are balloon-borne meteorological sensors used to acquire profiles of temperature and humidity. Radiosonde data are essential inputs for numerical weather prediction models and are used for climate research, particularly in the creation of reanalysis products. However, radiosonde programs are costly to maintain, in particular in the remote regions of the Arctic (e.g., $440,000/yr at Summit, Greenland), where only 40 of approximately 1000 routine global launches are made. The climate of this data-sparse region is poorly understood and forecast data assimilation procedures are designed for global applications. Thus, observations may be rejected from the data assimilation because they are too far from the model expectations. For the most cost-efficient deployment of resources and to improve forecasting methods, analyses of the effectiveness of individual radiosonde programs are necessary. Here, we evaluate how radiosondes launched twice daily (0 and 12 UTC) from Summit Station, Greenland, (72.58⁰N, 38.48⁰W, 3210 masl) influence the European Centre for Medium Range Weather Forecasting (ECMWF) operational forecasts from June 2013 through May of 2015. A statistical analysis is conducted to determine the impact of the observations on the forecast model and the meteorological regimes that the model fails to reproduce are identified. Assimilation rates in the inversion layer are lower than any other part of the troposphere. Above the inversion, assimilation rates range from 85%-100%, 60%-98%, and > 99% for temperature, humidity, and wind, respectively. The lowest assimilation rates are found near the surface, possibly associated with biases in the representation of the temperature inversion by the ECMWF model at Summit. Consequently, assimilation rates are lower near the surface during winter when strong temperature inversions are frequently observed. Our findings benefit the scientific community who uses this information for climatological analysis of the

  18. Analysis of Computational Models of Shaped Charges for Jet Formation and Penetration

    Science.gov (United States)

    Haefner, Jonah; Ferguson, Jim

    2016-11-01

    Shaped charges came into use during the Second World War demonstrating the immense penetration power of explosively formed projectiles and since has become a tool used by nearly every nation in the world. Penetration is critically dependent on how the metal liner is collapsed into a jet. The theory of jet formation has been studied in depth since the late 1940s, based on simple models that neglect the strength and compressibility of the metal liner. Although attempts have been made to improve these models, simplifying assumptions limit the understanding of how the material properties affect the jet formation. With a wide range of material and strength models available for simulation, a validation study was necessary to guide code users in choosing models for shaped charge simulations. Using PAGOSA, a finite-volume Eulerian hydrocode designed to model hypervelocity materials and strong shock waves developed by Los Alamos National Laboratory, and experimental data, we investigated the effects of various equations of state and material strength models on jet formation and penetration of a steel target. Comparing PAGOSA simulations against modern experimental data, we analyzed the strengths and weaknesses of available computational models. LA-UR-16-25639 Los Alamos National Laboratory.

  19. Central Station Design Options

    DEFF Research Database (Denmark)

    2011-01-01

    . The work identifies the architecture, sizing and siting of prospective Central Stations in Denmark, which can be located at shopping centers, large car parking lots or gas stations. Central Stations are planned to be integrated in the Danish distribution grid. The Danish island of Bornholm, where a high...... penetration of wind power is present, is considered as special case. The distribution grid in Denmark is built using larger secondary distribution transformers (e.g. 630 kVA) which in general allows higher flexibility for the installation of Central Stations, compared to Bornholm’s distribution grid...... kWh battery-EV is not feasible in Bornholm at the 0.4 kV level, due to predominantly small size secondary distribution transformers, in the range of 100 - 200 kVA. This is possible at the 10kV level (MV level), if the Fast Charging station is equipped with its own dedicated transformer. With DC...

  20. Relativistic Dynamics of a Charged Sphere. Updating the Lorentz-Abraham Model.

    Science.gov (United States)

    Yaghjian, Arthur D.

    "This is a remarkable book. […] A fresh and novel approach to old problems and to their solution." Fritz Rohrlich, Emeritus Professor of Physics, Syracuse University This book takes a fresh, systematic approach to determining the equation of motion for the classical model of the electron introduced by Lorentz more than 100 years ago. The original derivations of Lorentz, Abraham, Poincaré and Schott are modified and generalized for the charged insulator model of the electron to obtain an equation of motion consistent with causal solutions to the Maxwell-Lorentz equations and the equations of special relativity. The solutions to the resulting equation of motion are free of pre-acceleration and runaway behavior. Binding forces and a total stress momentum energy tensor are derived for the charged insulator model. General expressions for synchrotron radiation emerge in a form convenient for determining the motion of the electron. Appendices provide simplified derivations of the self-force and power at arbitrary velocity. In this Second Edition, the method used for eliminating the noncausal pre-acceleration from the equation of motion has been generalized to eliminate pre-deceleration as well. The generalized method is applied to obtain the causal solution to the equation of motion of a charge accelerating in a uniform electric field for a finite time interval. Alternative derivations of the Landau-Lifshitz approximation to the Lorentz-Abraham-Dirac equation of motion are also given, along with Spohn’s elegant solution of this approximate equation for a charge moving in a uniform magnetic field. The book is a valuable resource for students and researchers in physics, engineering and the history of science.

  1. Self-Consistent Approach to Global Charge Neutrality in Electrokinetics: A Surface Potential Trap Model

    Directory of Open Access Journals (Sweden)

    Li Wan

    2014-03-01

    Full Text Available In this work, we treat the Poisson-Nernst-Planck (PNP equations as the basis for a consistent framework of the electrokinetic effects. The static limit of the PNP equations is shown to be the charge-conserving Poisson-Boltzmann (CCPB equation, with guaranteed charge neutrality within the computational domain. We propose a surface potential trap model that attributes an energy cost to the interfacial charge dissociation. In conjunction with the CCPB, the surface potential trap can cause a surface-specific adsorbed charge layer σ. By defining a chemical potential μ that arises from the charge neutrality constraint, a reformulated CCPB can be reduced to the form of the Poisson-Boltzmann equation, whose prediction of the Debye screening layer profile is in excellent agreement with that of the Poisson-Boltzmann equation when the channel width is much larger than the Debye length. However, important differences emerge when the channel width is small, so the Debye screening layers from the opposite sides of the channel overlap with each other. In particular, the theory automatically yields a variation of σ that is generally known as the “charge regulation” behavior, attendant with predictions of force variation as a function of nanoscale separation between two charged surfaces that are in good agreement with the experiments, with no adjustable or additional parameters. We give a generalized definition of the ζ potential that reflects the strength of the electrokinetic effect; its variations with the concentration of surface-specific and surface-nonspecific salt ions are shown to be in good agreement with the experiments. To delineate the behavior of the electro-osmotic (EO effect, the coupled PNP and Navier-Stokes equations are solved numerically under an applied electric field tangential to the fluid-solid interface. The EO effect is shown to exhibit an intrinsic time dependence that is noninertial in its origin. Under a step-function applied

  2. Self-Consistent Approach to Global Charge Neutrality in Electrokinetics: A Surface Potential Trap Model

    Science.gov (United States)

    Wan, Li; Xu, Shixin; Liao, Maijia; Liu, Chun; Sheng, Ping

    2014-01-01

    In this work, we treat the Poisson-Nernst-Planck (PNP) equations as the basis for a consistent framework of the electrokinetic effects. The static limit of the PNP equations is shown to be the charge-conserving Poisson-Boltzmann (CCPB) equation, with guaranteed charge neutrality within the computational domain. We propose a surface potential trap model that attributes an energy cost to the interfacial charge dissociation. In conjunction with the CCPB, the surface potential trap can cause a surface-specific adsorbed charge layer σ. By defining a chemical potential μ that arises from the charge neutrality constraint, a reformulated CCPB can be reduced to the form of the Poisson-Boltzmann equation, whose prediction of the Debye screening layer profile is in excellent agreement with that of the Poisson-Boltzmann equation when the channel width is much larger than the Debye length. However, important differences emerge when the channel width is small, so the Debye screening layers from the opposite sides of the channel overlap with each other. In particular, the theory automatically yields a variation of σ that is generally known as the "charge regulation" behavior, attendant with predictions of force variation as a function of nanoscale separation between two charged surfaces that are in good agreement with the experiments, with no adjustable or additional parameters. We give a generalized definition of the ζ potential that reflects the strength of the electrokinetic effect; its variations with the concentration of surface-specific and surface-nonspecific salt ions are shown to be in good agreement with the experiments. To delineate the behavior of the electro-osmotic (EO) effect, the coupled PNP and Navier-Stokes equations are solved numerically under an applied electric field tangential to the fluid-solid interface. The EO effect is shown to exhibit an intrinsic time dependence that is noninertial in its origin. Under a step-function applied electric field, a

  3. Control of Warm Compression Stations Using Model Predictive Control: Simulation and Experimental Results

    Science.gov (United States)

    Bonne, F.; Alamir, M.; Bonnay, P.

    2017-02-01

    This paper deals with multivariable constrained model predictive control for Warm Compression Stations (WCS). WCSs are subject to numerous constraints (limits on pressures, actuators) that need to be satisfied using appropriate algorithms. The strategy is to replace all the PID loops controlling the WCS with an optimally designed model-based multivariable loop. This new strategy leads to high stability and fast disturbance rejection such as those induced by a turbine or a compressor stop, a key-aspect in the case of large scale cryogenic refrigeration. The proposed control scheme can be used to achieve precise control of pressures in normal operation or to avoid reaching stopping criteria (such as excessive pressures) under high disturbances (such as a pulsed heat load expected to take place in future fusion reactors, expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor ITER or the Japan Torus-60 Super Advanced fusion experiment JT-60SA). The paper details the simulator used to validate this new control scheme and the associated simulation results on the SBTs WCS. This work is partially supported through the French National Research Agency (ANR), task agreement ANR-13-SEED-0005.

  4. Urban Climate Station Site Selection Through Combined Digital Surface Model and Sun Angle Calculations

    Science.gov (United States)

    Kidd, Chris; Chapman, Lee

    2012-01-01

    Meteorological measurements within urban areas are becoming increasingly important due to the accentuating effects of climate change upon the Urban Heat Island (UHI). However, ensuring that such measurements are representative of the local area is often difficult due to the diversity of the urban environment. The evaluation of sites is important for both new sites and for the relocation of established sites to ensure that long term changes in the meteorological and climatological conditions continue to be faithfully recorded. Site selection is traditionally carried out in the field using both local knowledge and visual inspection. This paper exploits and assesses the use of lidar-derived digital surface models (DSMs) to quantitatively aid the site selection process. This is acheived by combining the DSM with a solar model, first to generate spatial maps of sky view factors and sun-hour potential and second, to generate site-specific views of the horizon. The results show that such a technique is a useful first-step approach to identify key sites that may be further evaluated for the location of meteorological stations within urban areas.

  5. A computational fluid dynamic modelling approach to assess the representativeness of urban monitoring stations.

    Science.gov (United States)

    Santiago, Jose Luis; Martín, Fernando; Martilli, Alberto

    2013-06-01

    Air quality measurements of urban monitoring stations have a limited spatial representativeness due to the complexity of urban meteorology and emissions distribution. In this work, a methodology based on a set of computational fluid dynamics simulations based on Reynolds-Averaged Navier-Stokes equations (RANS-CFD) for different meteorological conditions covering several months is developed in order to analyse the spatial representativeness of urban monitoring stations and to complement their measured concentrations. The methodology has been applied to two urban areas nearby air quality traffic-oriented stations in Pamplona and Madrid (Spain) to analyse nitrogen oxides concentrations. The computed maps of pollutant concentrations around each station show strong spatial variability being very difficult to comply with the European legislation concerning the spatial representativeness of traffic-oriented air quality stations. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Lightning attachment models and improvement of the modelling of the space charges; Modeles d'attachement des leaders de foudre au sol et amelioration de la prise en compte des charges d'espace

    Energy Technology Data Exchange (ETDEWEB)

    Bedja, A.; Auriol, Ph.; Buret, F. [Centre de Genie Electrique de Lyon (Cegely), Ecole Centrale de Lyon, 69 - Ecully (France)

    2005-04-01

    In this paper, we analyse initially the different models which have been developed to simulate the lightning attachment process. The advantages and the limitations of each model are presented. In the second part of this work, we will present the numerically model elaborated which simulate the spatial and temporal development of the space charge emitted by both the lightning rod and the ground surface. This model constitutes a first step to improve the initiation and the propagation criterions of the upward leader. (author)

  7. A stochastic model of gamma-ray induced oxide charge distribution and threshold voltage shift of MOS transistors

    Directory of Open Access Journals (Sweden)

    Kevkić Tijana S.

    2012-01-01

    Full Text Available A stochastic model of gamma-ray radiation effects on the density of the induced charge in silicon dioxide films of MOS transistors is presented in this paper. It is assumed that both radiation induced charge generation and trapped charge recombination are stochastic processes. For estimating gamma-ray induced charges spatially distributed in silicon dioxide films, a procedure similar to the Monte Carlo method was used. The proposed model implemented in the programming language MATHEMATICA enables us, for the first time, to show the gamma-ray induced charge distribution as a function of gamma-ray doses. Using the developed model, we have also calculated the corresponding threshold voltage shifts of MOS transistors. These results were compared with the experimentally determined threshold voltage shift of MOS transistors with different voltages applied during irradiation vs. gamma radiation doses. Satisfactory agreements were obtained.

  8. Post-IOC space station: Models of operation and their implications for organizational behavior, performance and effectiveness

    Science.gov (United States)

    Danford, S.; Meindl, J.; Hunt, R.

    1985-01-01

    Issues of crew productivity during design work on space station are discussed. The crew productivity is defined almost exclusively in terms of human factors engineering and habitability design concerns. While such spatial environmental conditions are necessary to support crew performance and productivity, they are not sufficient to ensure high levels of crew performance and productivity on the post-Initial Operational Configurations (IOC) space station. The role of the organizational environment as a complement to the spatial environment for influencing crew performance in such isolated and confined work settings is examined. Three possible models of operation for post-IOC space station's organizational environment are identified and it is explained how they and space station's spatial environment will combine and interact to occasion patterns of crew behavior is suggested. A three phase program of research design: (1) identify patterns of crew behavior likely to be occasioned on post-IOC space station for each of the three models of operation; and (2) to determine proactive/preventative management strategies which could be adopted to maximize the emergence of preferred outcomes in crew behavior under each of the several spatial and organizational environment combinations.

  9. Fuzzy modelling for the state-of-charge estimation of lead-acid batteries

    Science.gov (United States)

    Burgos, Claudio; Sáez, Doris; Orchard, Marcos E.; Cárdenas, Roberto

    2015-01-01

    This paper introduces a novel fuzzy model based structure for the characterisation of discharge processes in lead-acid batteries. This structure is based on a fuzzy model that characterises the relationship between the battery open-circuit voltage (Voc), the state of charge (SoC), and the discharge current. The model is identified and validated using experimental data that is obtained from an experimental system designed to test battery banks with several charge/discharge profiles. For model identification purposes, two standard experimental tests are implemented; one of these tests is used to identify the Voc-SoC curve, while the other helps to identify additional parameters of the model. The estimation of SoC is performed using an Extended Kalman Filter (EKF) with a state transition equation that is based on the proposed fuzzy model. Performance of the proposed estimation framework is compared with other parametric approaches that are inspired on electrical equivalents; e.g., Thevenin, Plett, and Copetti.

  10. A dynamic parking charge optimal control model under perspective of commuters' evolutionary game behavior

    Science.gov (United States)

    Lin, XuXun; Yuan, PengCheng

    2018-01-01

    In this research we consider commuters' dynamic learning effect by modeling the trip mode choice behavior from a new perspective of dynamic evolutionary game theory. We explore the behavior pattern of different types of commuters and study the evolution path and equilibrium properties under different traffic conditions. We further establish a dynamic parking charge optimal control (referred to as DPCOC) model to alter commuters' trip mode choice while minimizing the total social cost. Numerical tests show. (1) Under fixed parking fee policy, the evolutionary results are completely decided by the travel time and the only method for public transit induction is to increase the parking charge price. (2) Compared with fixed parking fee policy, DPCOC policy proposed in this research has several advantages. Firstly, it can effectively turn the evolutionary path and evolutionary stable strategy to a better situation while minimizing the total social cost. Secondly, it can reduce the sensitivity of trip mode choice behavior to traffic congestion and improve the ability to resist interferences and emergencies. Thirdly, it is able to control the private car proportion to a stable state and make the trip behavior more predictable for the transportation management department. The research results can provide theoretical basis and decision-making references for commuters' mode choice prediction, dynamic setting of urban parking charge prices and public transit induction.

  11. Mechanistic modeling of ion-exchange process chromatography of charge variants of monoclonal antibody products.

    Science.gov (United States)

    Kumar, Vijesh; Leweke, Samuel; von Lieres, Eric; Rathore, Anurag S

    2015-12-24

    Ion-exchange chromatography (IEX) is universally accepted as the optimal method for achieving process scale separation of charge variants of a monoclonal antibody (mAb) therapeutic. These variants are closely related to the product and a baseline separation is rarely achieved. The general practice is to fractionate the eluate from the IEX column, analyze the fractions and then pool the desired fractions to obtain the targeted composition of variants. This is, however, a very cumbersome and time consuming exercise. A mechanistic model that is capable of simulating the peak profile will be a much more elegant and effective way to make a decision on the pooling strategy. This paper proposes a mechanistic model, based on the general rate model, to predict elution peak profile for separation of the main product from its variants. The proposed approach uses inverse fit of process scale chromatogram for estimation of model parameters using the initial values that are obtained from theoretical correlations. The packed bed column has been modeled along with the chromatographic system consisting of the mixer, tubing and detectors as a series of dispersed plug flow and continuous stirred tank reactors. The model uses loading ranges starting at 25% to a maximum of 70% of the loading capacity and hence is applicable to process scale separations. Langmuir model has been extended to include the effects of salt concentration and temperature on the model parameters. The extended Langmuir model that has been proposed uses one less parameter than the SMA model and this results in a significant ease of estimating the model parameters from inverse fitting. The proposed model has been validated with experimental data and has been shown to successfully predict peak profile for a range of load capacities (15-28mg/mL), gradient lengths (10-30CV), bed heights (6-20cm), and for three different resins with good accuracy (as measured by estimation of residuals). The model has been also

  12. Electrochemical machining with ultrashort voltage pulses: modelling of charging dynamics and feature profile evolution.

    Science.gov (United States)

    Kenney, Jason A; Hwang, Gyeong S

    2005-07-01

    A two-dimensional computational model is developed to describe electrochemical nanostructuring of conducting materials with ultrashort voltage pulses. The model consists of (1) a transient charging simulation to describe the evolution of the overpotentials at the tool and workpiece surfaces and the resulting dissolution currents and (2) a feature profile evolution tool which uses the level set method to describe either vertical or lateral etching of the workpiece. Results presented include transient currents at different separations between tool and workpiece, evolution of overpotentials and dissolution currents as a function of position along the workpiece, and etch profiles as a function of pulse duration.

  13. Phase diagram of the restricted primitive model: charge-ordering instability

    Directory of Open Access Journals (Sweden)

    O.V.Patsahan

    2004-01-01

    Full Text Available We study the phase behaviour of the restricted primitive model (RPM using a microscopic approach based on the method of collective variables with a reference system. Starting from the Hamiltonian of the RPM we derive the functional of the grand partition function given in terms of the two collective variables: the collective variables ρk and ck describing fluctuations of the total number density and charge density, respectively. Within the framework of the Gaussian approximation we found the boundary of stability with respect to fluctuations of the charge density. It is shown that due to the approximated character of the theory the boundary of stability is very sensitive to the particular choice of the long-range part of potential inside the hard core. This point is discussed in more detail.

  14. Smooth approximation model of dispersion with strong space charge for continuous beams

    Directory of Open Access Journals (Sweden)

    S. Bernal

    2011-10-01

    Full Text Available We apply the Venturini-Reiser (V-R envelope-dispersion equations [M. Venturini and M. Reiser, Phys. Rev. Lett. 81, 96 (1998PRLTAO0031-900710.1103/PhysRevLett.81.96] to a continuous beam in a uniform focusing/bending lattice to study the combined effects of linear dispersion and space charge. Within this simple model we investigate the scaling of average dispersion and the effects on beam dimensions and show that the V-R equations lead to the correct zero-current limits. We also introduce a generalization of the space charge intensity parameter and apply it to the University of Maryland Electron Ring and other machines. In addition, we present results of calculations to test the smooth approximation by solving the V-R original equations and also through simulations with the matrix code ELEGANT.

  15. [Diffusion and diffusion-osmosis models of the charged macromolecule transfer in barriers of biosystems].

    Science.gov (United States)

    Varakin, A I; Mazur, V V; Arkhipova, N V; Serianov, Iu V

    2009-01-01

    Mathematical models of the transfer of charged macromolecules have been constructed on the basis of the classical equations of electromigration diffusion of Helmholtz-Smolukhovskii, Goldman, and Goldman-Hodgkin-Katz. It was shown that ion transfer in placental (mimicking lipid-protein barriers) and muscle barriers occurs by different mechanisms. In placental barriers, the electromigration diffusion occurs along lipid-protein channels formed due to the conformational deformation of phospholipid and protein molecules with the coefficients of diffusion D = (2.6-3.6) x 10(-8) cm2/s. The transfer in muscle barriers is due to the migration across charged interfibrillar channels with the negative diffusion activation energy, which is explained by changes in the structure of muscle fibers and expenditures of thermal energy for the extrusion of Cl- from channel walls with the diffusion coefficient D = (6.0-10.0) x 10(-6) cm2/s.

  16. CHARGING RAILWAY INFRASTRUCTURE MODELS AND THEIR IMPACT TO COMPETITIVENESS OF RAILWAY TRANSPORT

    Directory of Open Access Journals (Sweden)

    Anna DOLINAYOVA

    2017-04-01

    Full Text Available The paper deals with the impact the charging railway infrastructure access has on the competitiveness of railway transport in the selected European countries. It researched into the development of indicators that indicate the competition in the railways transport market, such as volume of transport, traffic performances, and number of trains of private railway operators compared with national operators. It used the new approach for research of the share of railway transport in the transport market. The research was based on a comparative analysis of models of charging railway infrastructure, subsidies to rail infrastructure, and development of transport performances of all rail operators. The results of research are presented in terms of freight and passenger railway transport.

  17. Polarizable charge equilibration model for predicting accurate electrostatic interactions in molecules and solids

    Science.gov (United States)

    Naserifar, Saber; Brooks, Daniel J.; Goddard, William A.; Cvicek, Vaclav

    2017-03-01

    Electrostatic interactions play a critical role in determining the properties, structures, and dynamics of chemical, biochemical, and material systems. These interactions are described well at the level of quantum mechanics (QM) but not so well for the various models used in force field simulations of these systems. We propose and validate a new general methodology, denoted PQEq, to predict rapidly and dynamically the atomic charges and polarization underlying the electrostatic interactions. Here the polarization is described using an atomic sized Gaussian shaped electron density that can polarize away from the core in response to internal and external electric fields, while at the same time adjusting the charge on each core (described as a Gaussian function) so as to achieve a constant chemical potential across all atoms of the system. The parameters for PQEq are derived from experimental atomic properties of all elements up to Nobelium (atomic no. = 102). We validate PQEq by comparing to QM interaction energy as probe dipoles are brought along various directions up to 30 molecules containing H, C, N, O, F, Si, P, S, and Cl atoms. We find that PQEq predicts interaction energies in excellent agreement with QM, much better than other common charge models such as obtained from QM using Mulliken or ESP charges and those from standard force fields (OPLS and AMBER). Since PQEq increases the accuracy of electrostatic interactions and the response to external electric fields, we expect that PQEq will be useful for a large range of applications including ligand docking to proteins, catalytic reactions, electrocatalysis, ferroelectrics, and growth of ceramics and films, where it could be incorporated into standard force fields as OPLS, AMBER, CHARMM, Dreiding, ReaxFF, and UFF.

  18. Southeast Regional Experiment Station

    Science.gov (United States)

    1994-08-01

    This is the final report of the Southeast Regional Experiment Station project. The Florida Solar Energy Center (FSEC), a research institute of the University of Central Florida (UCF), has operated the Southeast Regional Experiment Station (SE RES) for the US Department of Energy (DOE) since September 1982. Sandia National Laboratories, Albuquerque (SNLA) provides technical program direction for both the SE RES and the Southwest Regional Experiment Station (SW RES) located at the Southwest Technology Development Institute at Las Cruces, New Mexico. This cooperative effort serves a critical role in the national photovoltaic program by conducting system evaluations, design assistance and technology transfer to enhance the cost-effective utilization and development of photovoltaic technology. Initially, the research focus of the SE RES program centered on utility-connected PV systems and associated issues. In 1987, the SE RES began evaluating amorphous silicon (a-Si) thin-film PV modules for application in utility-interactive systems. Stand-alone PV systems began receiving increased emphasis at the SE RES in 1986. Research projects were initiated that involved evaluation of vaccine refrigeration, water pumping and other stand-alone power systems. The results of this work have led to design optimization techniques and procedures for the sizing and modeling of PV water pumping systems. Later recent research at the SE RES included test and evaluation of batteries and charge controllers for stand-alone PV system applications. The SE RES project provided the foundation on which FSEC achieved national recognition for its expertise in PV systems research and related technology transfer programs. These synergistic products of the SE RES illustrate the high visibility and contributions the FSEC PV program offers to the DOE.

  19. Model for screened, charge-regulated electrostatics of an eye lens protein: Bovine gammaB-crystallin

    Science.gov (United States)

    Wahle, Christopher W.; Martini, K. Michael; Hollenbeck, Dawn M.; Langner, Andreas; Ross, David S.; Hamilton, John F.; Thurston, George M.

    2017-09-01

    We model screened, site-specific charge regulation of the eye lens protein bovine gammaB-crystallin (γ B ) and study the probability distributions of its proton occupancy patterns. Using a simplified dielectric model, we solve the linearized Poisson-Boltzmann equation to calculate a 54 ×54 work-of-charging matrix, each entry being the modeled voltage at a given titratable site, due to an elementary charge at another site. The matrix quantifies interactions within patches of sites, including γ B charge pairs. We model intrinsic p K values that would occur hypothetically in the absence of other charges, with use of experimental data on the dependence of p K values on aqueous solution conditions, the dielectric model, and literature values. We use Monte Carlo simulations to calculate a model grand-canonical partition function that incorporates both the work-of-charging and the intrinsic p K values for isolated γ B molecules and we calculate the probabilities of leading proton occupancy configurations, for 4

    model γ B titration data. At p H 7.1 and Debye length 6.0 Å, on a given γ B molecule the predicted top occupancy pattern is present nearly 20% of the time, and 90% of the time one or another of the first 100 patterns will be present. Many of these occupancy patterns differ in net charge sign as well as in surface voltage profile. We illustrate how charge pattern probabilities deviate from the multinomial distribution that would result from use of effective p K values alone and estimate the extents to which γ B charge pattern distributions broaden at lower p H and narrow as ionic strength is lowered. These results suggest that for accurate modeling of orientation-dependent γ B -γ B interactions, consideration of numerous pairs of proton occupancy patterns will be needed.

  20. An Implementation of Estimation Techniques to a Hydrological Model for Prediction of Runoff to a Hydroelectric Power-Station

    Directory of Open Access Journals (Sweden)

    Magne Fjeld

    1981-01-01

    Full Text Available Parameter and state estimation algorithms have been applied to a hydrological model of a catchment area in southern Norway to yield improved control of the household of water resources and better economy and efficiency in the running of the power station, as experience proves since the system was installed on-line in the summer of 1978.

  1. MODELING OF THE HEAT PUMP STATION CONTROLABLE LOOP OF AN INTERMEDIATE HEAT-TRANSFER AGENT (Part II

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2011-08-01

    Full Text Available It is studied the model of the heat pump station controllable loop of an intermediate heat-transfer agent for the use in wineries. There are demonstrated transients after the disturbing action of the temperature on the input of cooling jacket of the fermentation stirred tank. There are compared different control laws of the object.

  2. Prediction Model of Battery State of Charge and Control Parameter Optimization for Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Bambang Wahono

    2015-07-01

    Full Text Available This paper presents the construction of a battery state of charge (SOC prediction model and the optimization method of the said model to appropriately control the number of parameters in compliance with the SOC as the battery output objectives. Research Centre for Electrical Power and Mechatronics, Indonesian Institute of Sciences has tested its electric vehicle research prototype on the road, monitoring its voltage, current, temperature, time, vehicle velocity, motor speed, and SOC during the operation. Using this experimental data, the prediction model of battery SOC was built. Stepwise method considering multicollinearity was able to efficiently develops the battery prediction model that describes the multiple control parameters in relation to the characteristic values such as SOC. It was demonstrated that particle swarm optimization (PSO succesfully and efficiently calculated optimal control parameters to optimize evaluation item such as SOC based on the model.

  3. Modeling of plug-in electric vehicle travel patterns and charging load based on trip chain generation

    Science.gov (United States)

    Wang, Dai; Gao, Junyu; Li, Pan; Wang, Bin; Zhang, Cong; Saxena, Samveg

    2017-08-01

    Modeling PEV travel and charging behavior is the key to estimate the charging demand and further explore the potential of providing grid services. This paper presents a stochastic simulation methodology to generate itineraries and charging load profiles for a population of PEVs based on real-world vehicle driving data. In order to describe the sequence of daily travel activities, we use the trip chain model which contains the detailed information of each trip, namely start time, end time, trip distance, start location and end location. A trip chain generation method is developed based on the Naive Bayes model to generate a large number of trips which are temporally and spatially coupled. We apply the proposed methodology to investigate the multi-location charging loads in three different scenarios. Simulation results show that home charging can meet the energy demand of the majority of PEVs in an average condition. In addition, we calculate the lower bound of charging load peak on the premise of lowest charging cost. The results are instructive for the design and construction of charging facilities to avoid excessive infrastructure.

  4. Optimal Allocation of Changing Station for Electric Vehicle Based on Queuing Theory

    Directory of Open Access Journals (Sweden)

    Yagang Zhang

    2016-11-01

    Full Text Available Electric vehicle as the main development direction of the future automotive industry, has gained attention worldwide. The rationality of the planning and construction of the power station, as the foundation of energy supply, is an important premise for the development of electric vehicles. In full consideration of the electric demand and electricity consumption, this paper proposes a new construction mode in which charging station and centralized charging station are appropriately combined and presents a location optimization model. Not only can this model be applied to determine the appropriate location for the power station, but it can use the queuing theory to determine the optimal number of power equipment, with which we can achieve the minimum costs. Finally, taking a certain city as an example, the optimum plan for power station is calculated by using this model, which provides an important reference for the study of electric vehicle infrastructure planning.

  5. Behavioral Phenotyping of Murine Disease Models with the Integrated Behavioral Station (INBEST).

    Science.gov (United States)

    Sakic, Boris; Cooper, Marcella P A; Taylor, Sarah E; Stojanovic, Milica; Zagorac, Bosa; Kapadia, Minesh

    2015-04-23

    Due to rapid advances in genetic engineering, small rodents have become the preferred subjects in many disciplines of biomedical research. In studies of chronic CNS disorders, there is an increasing demand for murine models with high validity at the behavioral level. However, multiple pathogenic mechanisms and complex functional deficits often impose challenges to reliably measure and interpret behavior of chronically sick mice. Therefore, the assessment of peripheral pathology and a behavioral profile at several time points using a battery of tests are required. Video-tracking, behavioral spectroscopy, and remote acquisition of physiological measures are emerging technologies that allow for comprehensive, accurate, and unbiased behavioral analysis in a home-base-like setting. This report describes a refined phenotyping protocol, which includes a custom-made monitoring apparatus (Integrated Behavioral Station, INBEST) that focuses on prolonged measurements of basic functional outputs, such as spontaneous activity, food/water intake and motivated behavior in a relatively stress-free environment. Technical and conceptual improvements in INBEST design may further promote reproducibility and standardization of behavioral studies.

  6. Wastewater Treatment Model in Washing Stations for Vehicles Transporting Dangerous Goods

    Directory of Open Access Journals (Sweden)

    Robert Muha

    2004-09-01

    Full Text Available Car washing is a task performed by every passenger carowner more or less frequently, mainly to achieve a finer appearanceof the vehicle rather than for the need for cleanness.In the transport business, the owner's concern is to presentclean and orderly vehicles on the road as a relevant external elementof order, implying good corporate image to customers. Onthe other hand, in dangerous goods transportation there areother reasons requiring special technology of washing, applicableto the transport means used, depending on the change oftype of goods in carriage, the preliminary preparation of a vehicleto load the cargo, or to undergo maintenance.Water applied in the technology of washing collects the residueof goods carried in the vehicle and is polluted to such an extentthat it cannot be discharged into sewers - nor directly into awatercourse - without previous treatment.The paper presents a solution model and a sequence oftechnological procedures involved in an efficient treatment ofthe polluted wastewater in tank wash stations, in which mostlyvehicles carrying ADR goods are washed.

  7. Probabilistic Agent-Based Model of Electric Vehicle Charging Demand to Analyse the Impact on Distribution Networks

    Directory of Open Access Journals (Sweden)

    Pol Olivella-Rosell

    2015-05-01

    Full Text Available Electric Vehicles (EVs have seen significant growth in sales recently and it is not clear how power systems will support the charging of a great number of vehicles. This paper proposes a methodology which allows the aggregated EV charging demand to be determined. The methodology applied to obtain the model is based on an agent-based approach to calculate the EV charging demand in a certain area. This model simulates each EV driver to consider its EV model characteristics, mobility needs, and charging processes required to reach its destination. This methodology also permits to consider social and economic variables. Furthermore, the model is stochastic, in order to consider the random pattern of some variables. The model is applied to Barcelona’s (Spain mobility pattern and uses the 37-node IEEE test feeder adapted to common distribution grid characteristics from Barcelona. The corresponding grid impact is analyzed in terms of voltage drop and four charging strategies are compared. The case study indicates that the variability in scenarios without control is relevant, but not in scenarios with control. Moreover, the voltages do not reach the minimum voltage allowed, but the MV/LV substations could exceed their capacities. Finally, it is determined that all EVs can charge during the valley without any negative effect on the distribution grid. In conclusion, it is determined that the methodology presented allows the EV charging demand to be calculated, considering different variables, to obtain better accuracy in the results.

  8. Charge collection efficiency degradation induced by MeV ions in semiconductor devices: Model and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Vittone, E., E-mail: ettore.vittone@unito.it [Department of Physics, NIS Research Centre and CNISM, University of Torino, via P. Giuria 1, 10125 Torino (Italy); Pastuovic, Z. [Centre for Accelerator Science (ANSTO), Locked bag 2001, Kirrawee DC, NSW 2234 (Australia); Breese, M.B.H. [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Garcia Lopez, J. [Centro Nacional de Aceleradores (CNA), Sevilla University, J. Andalucia, CSIC, Av. Thomas A. Edison 7, 41092 Sevilla (Spain); Jaksic, M. [Department for Experimental Physics, Ruder Boškovic Institute (RBI), P.O. Box 180, 10002 Zagreb (Croatia); Raisanen, J. [Department of Physics, University of Helsinki, Helsinki 00014 (Finland); Siegele, R. [Centre for Accelerator Science (ANSTO), Locked bag 2001, Kirrawee DC, NSW 2234 (Australia); Simon, A. [International Atomic Energy Agency (IAEA), Vienna International Centre, P.O. Box 100, 1400 Vienna (Austria); Institute of Nuclear Research of the Hungarian Academy of Sciences (ATOMKI), Debrecen (Hungary); Vizkelethy, G. [Sandia National Laboratories (SNL), PO Box 5800, Albuquerque, NM (United States)

    2016-04-01

    Highlights: • We study the electronic degradation of semiconductors induced by ion irradiation. • The experimental protocol is based on MeV ion microbeam irradiation. • The radiation induced damage is measured by IBIC. • The general model fits the experimental data in the low level damage regime. • Key parameters relevant to the intrinsic radiation hardness are extracted. - Abstract: This paper investigates both theoretically and experimentally the charge collection efficiency (CCE) degradation in silicon diodes induced by energetic ions. Ion Beam Induced Charge (IBIC) measurements carried out on n- and p-type silicon diodes which were previously irradiated with MeV He ions show evidence that the CCE degradation does not only depend on the mass, energy and fluence of the damaging ion, but also depends on the ion probe species and on the polarization state of the device. A general one-dimensional model is derived, which accounts for the ion-induced defect distribution, the ionization profile of the probing ion and the charge induction mechanism. Using the ionizing and non-ionizing energy loss profiles resulting from simulations based on the binary collision approximation and on the electrostatic/transport parameters of the diode under study as input, the model is able to accurately reproduce the experimental CCE degradation curves without introducing any phenomenological additional term or formula. Although limited to low level of damage, the model is quite general, including the displacement damage approach as a special case and can be applied to any semiconductor device. It provides a method to measure the capture coefficients of the radiation induced recombination centres. They can be considered indexes, which can contribute to assessing the relative radiation hardness of semiconductor materials.

  9. Atmospheric methane variability at the Peterhof station (Russia): ground-based observations and modeling

    Science.gov (United States)

    Makarova, Maria; Kirner, Oliver; Poberovskii, Anatoliy; Imhasin, Humud; Timofeyev, Yuriy; Virolainen, Yana; Makarov, Boris

    2014-05-01

    The Peterhof station (59.88 N, 29.83 E, 20 m asl) for atmospheric monitoring was founded by Saint - Petersburg State University, Russia. FTIR (Fourier transform IR) observations of methane total column are being carried out by Bruker IFS125 HR since 2009. The study presents a joint analysis of experimental data and EMAC (ECHAM/MESSy Atmospheric Chemistry model) model simulations for Peterhof over the period of 2009-2012. It was shown that CH4 total columns (TC) and column-averaged dry-air mole fractions (MF) obtained from observations are higher than model results with the difference of 1.3% and 0.3 % respectively. The correlation coefficients between FTIR and EMAC data are statistically significant (with 95% confidence) and equal to 0.82 ± 0.08 and 0.4 ± 0.1 for TC and MF of CH4 respectively. The high correlation for TCs shows that EMAC adequately reproduces CH4 variability due to meteorological processes in the atmosphere. On the other hand, the relatively low correlation coefficient for CH4 MF probably indicates an insufficiently precise knowledge of sources and sinks of the atmospheric methane. Amplitudes of the mean annual cycle of CH4 TC for experimental and model datasets (2009-2012) are of 2.1 % and 1.5 % respectively. The same amplitudes calculated for MF are less than for TC: 1.1% for FTIR and 0.6% for EMAC. Difference between FTIR and EMAC annual variations has pronounced seasonality with a maximum in September - November. It could be attributed to the underestimation of methane natural sources in the emission inventory used for EMAC simulations or by relatively coarse horizontal grid of the model (2.8°x2.8°). The analysis of modeling results allowed us to estimate the influence of the limited number of sunny days with FTIR measurement (i.e. specific meteorological conditions which usually take place during FTIR observations) on obtained FTIR estimates of the mean levels of TC and MF over 2009-2012. The systematic shifts of FTIR mean levels of TC and

  10. Role of charge screening and delocalization for lipophilic cation permeability of model and mitochondrial membranes.

    Science.gov (United States)

    Trendeleva, Tatiana A; Sukhanova, Evgenia I; Rogov, Anton G; Zvyagilskaya, Renata A; Seveina, Inna I; Ilyasova, Tatiana M; Cherepanov, Dmitry A; Skulachev, Vladimir P

    2013-09-01

    The effects of the mitochondria-targeted lipophilic cation dodecyltriphenylphosphonium (C12TPP, the charge is delocalized and screened by bulky hydrophobic residues) and those of lipophilic cations decyltriethylammonium bromide and cetyltrimethylammonium bromide (C10TEA and C16TMA, the charges are localized and screened by less bulky residues) on bilayer planar phospholipid membranes and tightly-coupled mitochondria from the yeast Yarrowia lipolytica have been compared. In planar membranes, C12TPP was found to generate a diffusion potential as if it easily penetrates these membranes. In the presence of palmitate, C12TPP induced H(+) permeability like plastoquinonyl decyltriphenilphosphonium that facilitates transfer of fatty acid anions (Severin et al., PNAS, 2010, 107, 663-668). C12TPP was shown to stimulate State 4 respiration of mitochondria and caused a mitochondrial membrane depolarization with a half-maximal effect at 6μM. Besides, C12TPP profoundly potentiated the uncoupling effect of endogenous or added fatty acids. C10TEA and C16TMA inhibited State 4 respiration and decreased the membrane potential, though at much higher concentrations than C12TPP, and they did not promote the uncoupling action of fatty acids. These relationships were modeled by molecular dynamics. They can be explained by different membrane permeabilities for studied cations, which in turn are due to different availabilities of the positive charge in these cations to water dipoles. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. In Vitro Assessment of Small Charged Pharmaceutical Aerosols in a Model of a Ventilated Neonate.

    Science.gov (United States)

    Holbrook, Landon; Hindle, Michael; Longest, P Worth

    2017-08-01

    Aerosolized medications may benefit infants receiving mechanical ventilation; however, the lung delivery efficiency of these aerosols is unacceptably low. In vitro experiments were conducted to evaluate aerosol delivery through conventional and modified ventilation systems to the end of a 3mm endotracheal tube (ETT) under steady state and realistic cyclic flow conditions. System modifications were employed to investigate the use of small charged particles and included streamlined components, a reduction in nebulizer liquid flow rate, synchronization with inspiration, and implementation of a previously designed low-flow induction charger (LF-IC), which was further modified in this study. Cyclic flow experiments implemented a modern ventilator with bias airflow and an inline flow meter, both of which are frequently excluded from in vitro tests but included in clinical practice. The modified LF-IC system demonstrated superior delivery efficiency to the end of the ETT (34%) compared with the commercial system (~1.3%) operating under cyclic ventilation conditions. These findings indicate that commercial systems still provide very low lung delivery efficiencies despite decades of innovation. In contrast, the modified system increased dose delivery to the end of the ETT by 26-fold. Despite initial concerns, the charged aerosol could be efficiently delivered through the small diameter ETT and reach the lungs. Future studies will be required to determine if the applied particle charge can eliminate expected high exhalation aerosol loss and will require the development of a realistic lung model.

  12. Modelling of Coke Layer Collapse during Ore Charging in Ironmaking Blast Furnace by DEM

    Science.gov (United States)

    Narita, Yoichi; Mio, Hiroshi; Orimoto, Takashi; Nomura, Seiji

    2017-06-01

    A technical issue in an ironmaking blast furnace operation is to realize the optimum layer thickness and the radial distribution of burden (ore and coke) to enhance its efficiency and productivity. When ore particles are charged onto the already-embedded coke layer, the coke layer-collapse phenomenon occurs. The coke layer-collapse phenomenon has a significant effect on the distribution of ore and coke layer thickness in the radial direction. In this paper, the mechanical properties of coke packed bed under ore charging were investigated by the impact-loading test and the large-scale direct shear test. Experimental results show that the coke particle is broken by the impact force of ore charging, and the particle breakage leads to weaken of coke-layer strength. The expression of contact force for coke in Discrete Element Method (DEM) was modified based on the measured data, and it followed by the 1/3-scaled experiment on coke's collapse phenomena. Comparing a simulation by modified model to the 1/3-scaled experiment, they agreed well in the burden distribution.

  13. Modelling of Coke Layer Collapse during Ore Charging in Ironmaking Blast Furnace by DEM

    Directory of Open Access Journals (Sweden)

    Narita Yoichi

    2017-01-01

    Full Text Available A technical issue in an ironmaking blast furnace operation is to realize the optimum layer thickness and the radial distribution of burden (ore and coke to enhance its efficiency and productivity. When ore particles are charged onto the already-embedded coke layer, the coke layer-collapse phenomenon occurs. The coke layer-collapse phenomenon has a significant effect on the distribution of ore and coke layer thickness in the radial direction. In this paper, the mechanical properties of coke packed bed under ore charging were investigated by the impact-loading test and the large-scale direct shear test. Experimental results show that the coke particle is broken by the impact force of ore charging, and the particle breakage leads to weaken of coke-layer strength. The expression of contact force for coke in Discrete Element Method (DEM was modified based on the measured data, and it followed by the 1/3-scaled experiment on coke’s collapse phenomena. Comparing a simulation by modified model to the 1/3-scaled experiment, they agreed well in the burden distribution.

  14. Superconductivity, charge-density waves, antiferromagnetism, and phase separation in the Hubbard-Holstein model

    Science.gov (United States)

    Karakuzu, Seher; Tocchio, Luca F.; Sorella, Sandro; Becca, Federico

    2017-11-01

    By using variational wave functions and quantum Monte Carlo techniques, we investigate the interplay between electron-electron and electron-phonon interactions in the two-dimensional Hubbard-Holstein model. Here, the ground-state phase diagram is triggered by several energy scales, i.e., the electron hopping t , the on-site electron-electron interaction U , the phonon energy ω0, and the electron-phonon coupling g . At half filling, the ground state is an antiferromagnetic insulator for U ≳2 g2/ω0 , while it is a charge-density-wave (or bipolaronic) insulator for U ≲2 g2/ω0 . In addition to these phases, we find a superconducting phase that intrudes between them. For ω0/t =1 , superconductivity emerges when both U /t and 2 g2/t ω0 are small; then, by increasing the value of the phonon energy ω0, it extends along the transition line between antiferromagnetic and charge-density-wave insulators. Away from half filling, phase separation occurs when doping the charge-density-wave insulator, while a uniform (superconducting) ground state is found when doping the superconducting phase. In the analysis of finite-size effects, it is extremely important to average over twisted boundary conditions, especially in the weak-coupling limit and in the doped case.

  15. Three dimensional space charge model for large high voltage satellites. [plasma sheath

    Science.gov (United States)

    Cooks, D.; Parker, L. W.; Mccoy, J. E.

    1980-01-01

    High power solar arrays for satellite power systems with dimensions of kilometers, and with tens of kilovolts distributed over their surface face many plasma interaction problems that must be properly anticipated. In most cases, the effects cannot be adequately modeled without detailed knowledge of the plasma sheath structure and space charge effects. Two computer programs were developed to provide fully self consistent plasma sheath models in three dimensions as a result of efforts to model the experimental plasma sheath studies at NASA/JSC. Preliminary results indicate that for the conditions considered, the Child-Langmuir diode theory can provide a useful estimate of the plasma sheath thickness. The limitations of this conclusion are discussed. Some of the models presented exhibit the strong ion focusing observed in the JSC experiments.

  16. Modeling of a heat pump charged with a non-azeotropic refrigerant mixture

    Science.gov (United States)

    Domanski, P.

    1986-01-01

    An analysis of the vapor compression cycle and the main components of an air-to-air heat pump charged with a binary non-azeotropic mixture has been performed for steady-state operation. The general heat pump simulation model HPBI has been formulated which is based on independent, analytical models of system components and the logic linking them together. The logic of the program requires an iterative solution of refrigerant pressure and enthalpy balances, and refrigerant mixture and individual mixture component mass inventories. The modeling effort emphasis was on the local thermodynamic phenomena which were described by fundamental heat transfer equations and equation of state relationships among material properties. In the compressor model several refrigerant locations were identified and the processes taking place between these locations accounted for all significant heat and pressure losses.

  17. Meso- and Micro-scale Modelling in China: Wind atlas analysis for 12 meteorological stations in NE China (Dongbei)

    DEFF Research Database (Denmark)

    Mortensen, Niels Gylling; Yang, Z.; Hansen, Jens Carsten

    As part of the “Meso-Scale and Micro-Scale Modelling in China” project, also known as the CMA component of the Sino-Danish Wind Energy Development Programme (WED), microscale modelling and analyses have been carried out for 12 meteorological stations in NE China. Wind speed and direction data from...... density (power curve) and calibrated anemometers are confirmed to be prerequisites for reliable predictions; project-specific wind atlas heights are highly recommended....

  18. L-MEB Model Calibration Over the Valencia Anchor Station Area

    Science.gov (United States)

    Lopez-Baeza, E.

    2009-04-01

    In the framework of ESA's SMOS (Soil Moisture and Ocean Salinity) Mission, several studies are being carried out over different types of land surfaces to study their microwave L-band emission (1.4 GHz). These studies are being integrated in the SMOS emission model (L-MEB, L-band Microwave Emission of the Biosphere, Wigneron et al. 2007), which is the core of the SMOS algorithm for the retrieval of land surface parameters from SMOS data. To contribute to Cal/Val activities at the Valencia Anchor Station (VAS) area (Caudete de las Fuentes, Valencia, Spain), one of the primary validation areas for SMOS land data and products (ESA SMOS Cal/Val AO, Project ID 3252, Lopez-Baeza et al., 2005), a number of experiments have been carried out to study the vegetation influence over the L-band emission proceeding from the soil surface. In the VAS area, a reduced number of homogeneous units have been defined according to the type and use of the soil, mainly, shrubs, vineyards, orchards (almond-and olive-trees) and Mediterranean pine forests. In order to implement the SMOS algorithm over this reference area, it is necessary to characterize and calibrate the L-MEB model for the different cover types. This work is significantly contributing to the definition of the VAS site as a validation area for SMOS land products of the size of a SMOS pixel (SMOS reference pixel). Shrubs and vineyards are the two most significant vegetation types which cover a large percentage of the area and for which very little information at L-band is available in the literature. These two types of vegetation covers have been studied in two separate dedicated experiments under the common name of MELBEX (Mediterranean Ecosystem L-Band characterisation EXperiment). The first one (MELBEX-I) took place over a shrub area characterised by a significant proportion of bare soil with superficial stones. The second one (MELBEX-II) was carried out from March to December 2007 over a large vineyard area. During the time

  19. The R package 'RLumModel': Simulating charge transfer in quartz

    Science.gov (United States)

    Friedrich, Johannes; Kreutzer, Sebastian; Schmidt, Christoph

    2017-04-01

    Kinetic models of quartz luminescence have gained an important role for predicting experimental results and for understanding charge transfers in (natural) quartz as well as for other dosimetric materials, e.g., Al2O3:C. We present the R package 'RLumModel', offering an easy-to-use tool for simulating quartz luminescence signals (TL, OSL, LM-OSL and RF) based on five integrated and published parameter sets as well as the possibility to use own parameters. Simulation commands can be created (a) using the Risø Sequence Editor, (b) a built-in SAR sequence generator or (c) self-explanatory keywords for customised sequences. Results can be analysed seamlessly using the R package 'Luminescence' along with a visualisation of concentrations of electrons and holes in every trap/centre as well as in the valence and conduction band during all stages of the simulation. Modelling luminescence signals can help understanding charge transfer processes occurring in nature or during measurements in the laboratory. This will lead to a better understanding of several processes concerning geoscientific questions, because quartz is the second most abundant mineral in the Earth's continental crust.

  20. Sensitivity Analysis of ETo for Five Current Models Using Monte-Carlo Simulation Case study: Bojnourd Synoptic Station

    Directory of Open Access Journals (Sweden)

    M. Makari

    2015-06-01

    Full Text Available The objective of this study is to analyze the sensitivity of ETo for five models including FAO-Penman-Monteith, modified Blaney-Criddle, Hargreaves, Hargreaves-Samani and Priestley –Taylor. Daily meteorological data of Bojnourd synoptic station including air temperature, relative humidity, actual duration sunshine and wind velocity were used for sensitivity analysis of five models. In order to produce random data at a specific range, Monte-Carlo simulation was performed. Annual and seasonal were calculated to indicate the sensitivity of ETo in simultaneous variations of meteorological variables in each model.The results obtained in this study showed that the sensitivity of in simultaneous variations of meteorological variables is higher in summer. In all models, the most sensitivity was seen in summer and spring and the least sensitivity was occurred in autumn and winter. Among the studied models, FAO-PM and BC models had the most annual sensitivity and PT model had the least annual sensitivity. All of the models had fairly high correlation coefficient with FAO-PM model but the quantity of and was different in each model. BC model had the most and the least and was seen in and PT. According to the findings in this study, it can be concluded that SH model is fairly suitable for estimation of in synoptic station.

  1. Numerical algorithm for triphasic model of charged and hydrated soft tissues

    Science.gov (United States)

    Hon, Y. C.; Lu, M. W.; Xue, W. M.; Zhou, X.

    This paper devises an efficient numerical algorithm for solving a two-dimensional triphasic model of charged and hydrated soft tissue by using the radial basis functions. The proposed numerical method is applied directly as a simple meshless collocation algorithm to approximate the solution of the governing system of continuity, momentum, and constitutive equations for the triphasic model. Since there is no requirement on meshing, the method can easily be applied to solve problems under complicated geometry. For verification, numerical simulations of stress, strain, and fluid flow patterns for a plane strain and an axisymmetric mechano-electrochemical coupling model with real synovial joint are given respectively. Classical domain decomposition technique is also combined successfully with the proposed method for solving large scale problems with numerical verification given in solving the axisymmetric case.

  2. Fire Stations

    Data.gov (United States)

    Department of Homeland Security — Fire Stations in the United States Any location where fire fighters are stationed or based out of, or where equipment that such personnel use in carrying out their...

  3. Regional travel-time residual studies and station correction from 1-D velocity models for some stations around Peninsular Malaysia and Singapore

    National Research Council Canada - National Science Library

    Osagie, Abel U; Nawawi, Mohd; Khalil, Amin Esmail; Abdullah, Khiruddin

    We have investigated the average P-wave travel-time residuals for some stations around Southern Thailand, Peninsular Malaysia and Singapore at regional distances. Six years (January, 2010–December, 2015...

  4. The Weak Charge of the Proton. A Search For Physics Beyond the Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    MacEwan, Scott J. [Univ. of Manitoba, Winnipeg, MB (Canada)

    2015-05-01

    The Qweak experiment, which completed running in May of 2012 at Jefferson Laboratory, has measured the parity-violating asymmetry in elastic electron-proton scattering at four-momentum transfer Q2 =0.025 (GeV/c)2 in order to provide the first direct measurement of the proton's weak charge, QWp. The Standard Model makes firm predictions for the weak charge; deviations from the predicted value would provide strong evidence of new physics beyond the Standard Model. Using an 89% polarized electron beam at 145 microA scattering from a 34.4 cm long liquid hydrogen target, scattered electrons were detected using an array of eight fused-silica detectors placed symmetric about the beam axis. The parity-violating asymmetry was then measured by reversing the helicity of the incoming electrons and measuring the normalized difference in rate seen in the detectors. The low Q2 enables a theoretically clean measurement; the higher-order hadronic corrections are constrained using previous parity-violating electron scattering world data. The experimental method will be discussed, with recent results constituting 4% of our total data and projections of our proposed uncertainties on the full data set.

  5. A Triphasic Orthotropic Laminate Model for Cartilage Curling Behavior: Fixed Charge Density vs. Mechanical Properties Inhomogeneity

    Science.gov (United States)

    Wan, Leo Q.; Guo, X. Edward; Mow, Van C.

    2010-01-01

    Osmotic pressure and associated residual stresses play important roles in cartilage development and biomechanical function. The curling behavior of articular cartilage was believed to be the combination of results from the osmotic pressure derived from fixed negative charges on proteoglycans and the structural and compositional and material property inhomogeneities within the tissue. In the present study, the in vitro swelling and curling behaviors of thin strips of cartilage were analyzed with a new structural model using the triphasic mixture theory with a collagen-proteoglycan solid matrix composed of a three-layered laminate with each layer possessing a distinct set of orthotropic properties. A conewise linear elastic matrix was also incorporated to account for the well-known tension-compression nonlinearity of the tissue. This model can account, for the first time, for the swelling-induced curvatures found in published experimental results on excised cartilage samples. The results suggest that for a charged hydrated soft tissue, such as articular cartilage, the balance of proteoglycan swelling and the collagen restraining within the solid matrix is the origin of the in situ residual stress, and that the layered collagen ultrastructure, e.g., relatively dense and with high stiffness at the articular surface, play the dominate role in determining curling behaviors of such tissues. PMID:20370250

  6. A triphasic orthotropic laminate model for cartilage curling behavior: fixed charge density versus mechanical properties inhomogeneity.

    Science.gov (United States)

    Wan, Leo Q; Guo, X Edward; Mow, Van C

    2010-02-01

    Osmotic pressure and associated residual stresses play important roles in cartilage development and biomechanical function. The curling behavior of articular cartilage was believed to be the combination of results from the osmotic pressure derived from fixed negative charges on proteoglycans and the structural and compositional and material property inhomogeneities within the tissue. In the present study, the in vitro swelling and curling behaviors of thin strips of cartilage were analyzed with a new structural model using the triphasic mixture theory with a collagen-proteoglycan solid matrix composed of a three-layered laminate with each layer possessing a distinct set of orthotropic properties. A conewise linear elastic matrix was also incorporated to account for the well-known tension-compression nonlinearity of the tissue. This model can account, for the first time, for the swelling-induced curvatures found in published experimental results on excised cartilage samples. The results suggest that for a charged-hydrated soft tissue, such as articular cartilage, the balance of proteoglycan swelling and the collagen restraining within the solid matrix is the origin of the in situ residual stress, and that the layered collagen ultrastructure, e.g., relatively dense and with high stiffness at the articular surface, play the dominate role in determining curling behaviors of such tissues.

  7. N=2 Sigma Model with Twisted Mass and Superpotential Central Charges and Solitons

    CERN Document Server

    Losev, A S

    2003-01-01

    We consider supersymmetric sigma models on the Kahler target spaces, with twisted mass. The Kahler spaces are assumed to have holomorphic Killing vectors. Introduction of a superpotential of a special type is known to be consistent with N=2 superalgebra (Alvarez-Gaume and Freedman). We show that the algebra acquires central charges in the anticommutators {Q_L, Q_L} and {Q_R, Q_R}. These central charges have no parallels, and they can exist only in two dimensions. The central extension of the N=2 superalgebra we found paves the way to a novel phenomenon -- spontaneous breaking of a part of supersymmetry. In the general case 1/2 of supersymmetry is spontaneously broken (the vacuum energy density is positive), while the remaining 1/2 is realized linearly. In the model at hand the standard fermion number is not defined, so that the Witten index as well as the Cecotti-Fendley-Intriligator-Vafa index are useless. We show how to construct an index for counting short multiplets in internal algebraic terms which is we...

  8. Space-charge-controlled field emission model of current conduction through Al2O3 films

    Science.gov (United States)

    Hiraiwa, Atsushi; Matsumura, Daisuke; Kawarada, Hiroshi

    2016-02-01

    This study proposes a model for current conduction in metal-insulator-semiconductor (MIS) capacitors, assuming the presence of two sheets of charge in the insulator, and derives analytical formulae of field emission (FE) currents under both negative and positive bias. Since it is affected by the space charge in the insulator, this particular FE differs from the conventional FE and is accordingly named the space-charge-controlled (SCC) FE. The gate insulator of this study was a stack of atomic-layer-deposition Al2O3 and underlying chemical SiO2 formed on Si substrates. The current-voltage (I-V) characteristics simulated using the SCC-FE formulae quantitatively reproduced the experimental results obtained by measuring Au- and Al-gated Al2O3/SiO2 MIS capacitors under both biases. The two sheets of charge in the Al2O3 films were estimated to be positive and located at a depth of greater than 4 nm from the Al2O3/SiO2 interface and less than 2 nm from the gate. The density of the former is approximately 1 × 1013 cm-2 in units of electronic charge, regardless of the type of capacitor. The latter forms a sheet of dipoles together with image charges in the gate and hence causes potential jumps of 0.4 V and 1.1 V in the Au- and Al-gated capacitors, respectively. Within a margin of error, this sheet of dipoles is ideally located at the gate/Al2O3 interface and effectively reduces the work function of the gate by the magnitude of the potential jumps mentioned above. These facts indicate that the currents in the Al2O3/SiO2 MIS capacitors are enhanced as compared to those in ideal capacitors and that the currents in the Al-gated capacitors under negative bias (electron emission from the gate) are more markedly enhanced than those in the Au-gated capacitors. The larger number of gate-side dipoles in the Al-gated capacitors is possibly caused by the reaction between the Al and Al2O3, and therefore gate materials that do not react with underlying gate insulators should be chosen

  9. Modelling soil moisture at SMOS scale by use of a SVAT model over the Valencia Anchor Station

    Science.gov (United States)

    Juglea, S.; Kerr, Y.; Mialon, A.; Wigneron, J.-P.; Lopez-Baeza, E.; Cano, A.; Albitar, A.; Millan-Scheiding, C.; Antolin, M. Carmen; Delwart, S.

    2010-05-01

    The main goal of the SMOS (Soil Moisture and Ocean Salinity) mission is to deliver global fields of surface soil moisture and sea surface salinity using L-band (1.4 GHz) radiometry. Within the context of the Science preparation for SMOS, the Valencia Anchor Station (VAS) experimental site, in Spain, was chosen to be one of the main test sites in Europe for Calibration/Validation (Cal/Val) activities. In this framework, the paper presents an approach consisting in accurately simulating a whole SMOS pixel by representing the spatial and temporal heterogeneity of the soil moisture fields over the wide VAS surface (50×50 km2). Ground and meteorological measurements over the area are used as the input of a Soil-Vegetation-Atmosphere-Transfer (SVAT) model, SURFEX (Externalized Surface) - module ISBA (Interactions between Soil-Biosphere-Atmosphere) to simulate the spatial and temporal distribution of surface soil moisture. The calibration as well as the validation of the ISBA model are performed using in situ soil moisture measurements. It is shown that a good consistency is reached when point comparisons between simulated and in situ soil moisture measurements are made. Actually, an important challenge in remote sensing approaches concerns product validation. In order to obtain an representative soil moisture mapping over the Valencia Anchor Station (50×50 km2 area), a spatialization method is applied. For verification, a comparison between the simulated spatialized soil moisture and remote sensing data from the Advanced Microwave Scanning Radiometer on Earth observing System (AMSR-E) and from the European Remote Sensing Satellites (ERS-SCAT) is performed. Despite the fact that AMSR-E surface soil moisture product is not reproducing accurately the absolute values, it provides trustworthy information on surface soil moisture temporal variability. However, during the vegetation growing season the signal is perturbed. By using the polarization ratio a better agreement is

  10. Modelling soil moisture at SMOS scale by use of a SVAT model over the Valencia Anchor Station

    Directory of Open Access Journals (Sweden)

    S. Juglea

    2010-05-01

    Full Text Available The main goal of the SMOS (Soil Moisture and Ocean Salinity mission is to deliver global fields of surface soil moisture and sea surface salinity using L-band (1.4 GHz radiometry. Within the context of the Science preparation for SMOS, the Valencia Anchor Station (VAS experimental site, in Spain, was chosen to be one of the main test sites in Europe for Calibration/Validation (Cal/Val activities. In this framework, the paper presents an approach consisting in accurately simulating a whole SMOS pixel by representing the spatial and temporal heterogeneity of the soil moisture fields over the wide VAS surface (50×50 km2. Ground and meteorological measurements over the area are used as the input of a Soil-Vegetation-Atmosphere-Transfer (SVAT model, SURFEX (Externalized Surface - module ISBA (Interactions between Soil-Biosphere-Atmosphere to simulate the spatial and temporal distribution of surface soil moisture. The calibration as well as the validation of the ISBA model are performed using in situ soil moisture measurements. It is shown that a good consistency is reached when point comparisons between simulated and in situ soil moisture measurements are made.

    Actually, an important challenge in remote sensing approaches concerns product validation. In order to obtain an representative soil moisture mapping over the Valencia Anchor Station (50×50 km2 area, a spatialization method is applied. For verification, a comparison between the simulated spatialized soil moisture and remote sensing data from the Advanced Microwave Scanning Radiometer on Earth observing System (AMSR-E and from the European Remote Sensing Satellites (ERS-SCAT is performed. Despite the fact that AMSR-E surface soil moisture product is not reproducing accurately the absolute values, it provides trustworthy information on surface soil moisture temporal variability. However, during the vegetation growing season the signal is perturbed. By using the

  11. Evaluation of Model Based State of Charge Estimation Methods for Lithium-Ion Batteries

    Directory of Open Access Journals (Sweden)

    Zhongyue Zou

    2014-08-01

    Full Text Available Four model-based State of Charge (SOC estimation methods for lithium-ion (Li-ion batteries are studied and evaluated in this paper. Different from existing literatures, this work evaluates different aspects of the SOC estimation, such as the estimation error distribution, the estimation rise time, the estimation time consumption, etc. The equivalent model of the battery is introduced and the state function of the model is deduced. The four model-based SOC estimation methods are analyzed first. Simulations and experiments are then established to evaluate the four methods. The urban dynamometer driving schedule (UDDS current profiles are applied to simulate the drive situations of an electrified vehicle, and a genetic algorithm is utilized to identify the model parameters to find the optimal parameters of the model of the Li-ion battery. The simulations with and without disturbance are carried out and the results are analyzed. A battery test workbench is established and a Li-ion battery is applied to test the hardware in a loop experiment. Experimental results are plotted and analyzed according to the four aspects to evaluate the four model-based SOC estimation methods.

  12. Dynamic analytical model for charge transport in octithiophene thin film transistors

    Science.gov (United States)

    Zorai, S.; Mansouri, S.; Bourguiga, R.

    2012-12-01

    In this paper, we develop a device model of an organic thin film transistor (OTFTs) in which the active layers are made of octithiophene. This model is based on variable range hopping theory, i.e., a carrier may either hop over a small distance with a high activation energy or hop over a long distance with a low activation energy. The model takes into account all the operating regimes in direct current and transient mode; the transistor symmetry is also considered. The model has been developed using a physical basis where the model parameters can easily be extracted. The current-voltage characteristics of short-channel organic TFTs have been calculated starting from the solution of the drain current equation for an enhancement mode p-channel MOSFET. A good agreement between theory model and experimental results is obtained. Different transport parameters are extracted by using a fitting method. We have extracted the mobility of charge in saturation regime using differential method. Based on first and second derivative of transfer characteristic we extracted a serial resistance, intrinsic mobility and threshold voltage. The mobility in saturation regime is reproduced using the VRH model. Finally, we give a simple small-signal equivalent circuit.

  13. Model of Organic Solar Cell Photocurrent Including the Effect of Charge Accumulation at Interfaces and Non-Uniform Carrier Generation

    DEFF Research Database (Denmark)

    Torto, Lorenzo; Cester, Andrea; Rizzo, Antonio

    2017-01-01

    We developed an improved model to fit the photocurrent density versus voltage in organic solar cells. The model has been validated by fitting data from P3HT:PCBM solar cells. Our model quantitatively accounts for the band bending near the electrodes caused by charge accumulation in the active layer...

  14. Lateral distribution of charged species along a polyelectrolyte probed with a fluorescence blob model.

    Science.gov (United States)

    Keyes-Baig, Christine; Mathew, Manoj; Duhamel, Jean

    2012-10-10

    The distribution of metal counterions binding onto the oppositely charged surface of a model polyelectrolyte, namely, DNA, was characterized by conducting fluorescence quenching experiments. In these experiments, DNA was used as a molecular ruler to measure the average distance (d(blob)) over which electron transfer takes place between DNA-intercalated ethidium bromide (DNA-EB) and the electrostatically bound divalent metal cations Ni(2+) and Cu(2+). Analysis of the fluorescence decays of DNA-EB quenched by Cu(2+) and Ni(2+) with the fluorescence blob model showed that d(blob) was equal to the Debye length (κ(-1)). This surprisingly simple result considering the overall complexity of the system under study led to the straightforward proposal that counterions bind to a polyelectrolyte by distributing themselves randomly into an array of self-defined subdomains of dimension κ(-1). In turn, this insight can be utilized to rationalize the complex behavior of polyelectrolytes in aqueous solution.

  15. The thermoballistic transport model a novel approach to charge carrier transport in semiconductors

    CERN Document Server

    Lipperheide, Reinhard

    2014-01-01

    The book presents a comprehensive survey of the thermoballistic approach to charge carrier transport in semiconductors. This semi-classical approach, which the authors have developed over the past decade, bridges the gap between the opposing drift-diffusion and ballistic  models of carrier transport. While incorporating basic features of the latter two models, the physical concept underlying the thermoballistic approach constitutes a novel, unifying scheme. It is based on the introduction of "ballistic configurations" arising from a random partitioning of the length of a semiconducting sample into ballistic transport intervals. Stochastic averaging of the ballistic carrier currents over the ballistic configurations results in a position-dependent thermoballistic current, which is the key element of the thermoballistic concept and forms  the point of departure for the calculation of all relevant transport properties. In the book, the thermoballistic concept and its implementation are developed in great detai...

  16. MODELLING OF CHARGE CARRIER MOBILITY FOR TRANSPORT BETWEEN ELASTIC POLYACETYLENE-LIKE POLYMER NANORODS

    Directory of Open Access Journals (Sweden)

    M. Mensik

    2017-03-01

    Full Text Available A quantum model solving the charge carrier mobility between polyacetylene-like polymer nanorods is presented. The model assumes: a Quantum mechanical calculation of hole on-chain delocalization involving electron-phonon coupling leading to the Peierls instability, b Hybridization coupling between the polymer backbone and side-groups (or environmental states, which act as hole traps, and c Semiclassical description of the inter-chain hole transfer in an applied voltage based on Marcus theory. We have found that mobility resonantly depends on the hybridization coupling between polymer and linked groups. We observed also non-trivial mobility dependences on the difference of energies of the highest occupied molecular orbitals localized on the polymer backbone and side-groups, respectively, and hole concentration. Those findings are important for optimization of hybrid opto-electronic devices.

  17. Universal Finite Size Corrections and the Central Charge in Non-solvable Ising Models

    Science.gov (United States)

    Giuliani, Alessandro; Mastropietro, Vieri

    2013-11-01

    We investigate a non-solvable two-dimensional ferromagnetic Ising model with nearest neighbor plus weak finite range interactions of strength λ. We rigorously establish one of the predictions of Conformal Field Theory (CFT), namely the fact that at the critical temperature the finite size corrections to the free energy are universal, in the sense that they are exactly independent of the interaction. The corresponding central charge, defined in terms of the coefficient of the first subleading term to the free energy, as proposed by Affleck and Blote-Cardy-Nightingale, is constant and equal to 1/2 for all and λ 0 a small but finite convergence radius. This is one of the very few cases where the predictions of CFT can be rigorously verified starting from a microscopic non solvable statistical model. The proof uses a combination of rigorous renormalization group methods with a novel partition function inequality, valid for ferromagnetic interactions.

  18. A Model for Monitoring GSM Base Station Radiation Safety in Nigeria

    Directory of Open Access Journals (Sweden)

    Dr. Godfrey Ekata

    2014-10-01

    Full Text Available A guideline for measuring the radio frequency (RF emissions from the base transceiver stations deployed by Global System Mobile Communications operators in Nigeria is proposed. The guide includes the procedures for measuring the emitted RF power and for determining whether or not the emission exceeds the maximum permissible limits in Nigeria airspace.

  19. Fractional-order modeling and State-of-Charge estimation for ultracapacitors

    Science.gov (United States)

    Zhang, Lei; Hu, Xiaosong; Wang, Zhenpo; Sun, Fengchun; Dorrell, David G.

    2016-05-01

    Ultracapacitors (UCs) have been widely recognized as an enabling energy storage technology in various industrial applications. They hold several advantages including high power density and exceptionally long lifespan over the well-adopted battery technology. Accurate modeling and State-of-Charge (SOC) estimation of UCs are essential for reliability, resilience, and safety in UC-powered system operations. In this paper, a novel fractional-order model composed of a series resistor, a constant-phase-element (CPE), and a Walburg-like element, is proposed to emulate the UC dynamics. The Grünald-Letnikov derivative (GLD) is then employed to discretize the continuous-time fractional-order model. The model parameters are optimally extracted using genetic algorithm (GA), based on the time-domain data acquired through the Federal Urban Driving Schedule (FUDS) test. By means of this fractional-order model, a fractional Kalman filter is synthesized to recursively estimate the UC SOC. Validation results prove that the proposed fractional-order modeling and state estimation scheme is accurate and outperforms current practice based on integer-order techniques.

  20. Charge Equalization Controller Algorithm for Series-Connected Lithium-Ion Battery Storage Systems: Modeling and Applications

    Directory of Open Access Journals (Sweden)

    Mahammad A. Hannan

    2017-09-01

    Full Text Available This study aims to develop an accurate model of a charge equalization controller (CEC that manages individual cell monitoring and equalizing by charging and discharging series-connected lithium-ion (Li-ion battery cells. In this concept, an intelligent control algorithm is developed to activate bidirectional cell switches and control direct current (DC–DC converter switches along with pulse width modulation (PWM generation. Individual models of an electric vehicle (EV-sustainable Li-ion battery, optimal power rating, a bidirectional flyback DC–DC converter, and charging and discharging controllers are integrated to develop a small-scale CEC model that can be implemented for 10 series-connected Li-ion battery cells. Results show that the charge equalization controller operates at 91% efficiency and performs well in equalizing both overdischarged and overcharged cells on time. Moreover, the outputs of the CEC model show that the desired balancing level occurs at 2% of state of charge difference and that all cells are operated within a normal range. The configuration, execution, control, power loss, cost, size, and efficiency of the developed CEC model are compared with those of existing controllers. The proposed model is proven suitable for high-tech storage systems toward the advancement of sustainable EV technologies and renewable source of applications.

  1. Electrostatically Embedded Many-Body Expansion for Neutral and Charged Metalloenzyme Model Systems.

    Science.gov (United States)

    Kurbanov, Elbek K; Leverentz, Hannah R; Truhlar, Donald G; Amin, Elizabeth A

    2012-01-10

    The electrostatically embedded many-body (EE-MB) method has proven accurate for calculating cohesive and conformational energies in clusters, and it has recently been extended to obtain bond dissociation energies for metal-ligand bonds in positively charged inorganic coordination complexes. In the present paper, we present four key guidelines that maximize the accuracy and efficiency of EE-MB calculations for metal centers. Then, following these guidelines, we show that the EE-MB method can also perform well for bond dissociation energies in a variety of neutral and negatively charged inorganic coordination systems representing metalloenzyme active sites, including a model of the catalytic site of the zinc-bearing anthrax toxin lethal factor, a popular target for drug development. In particular, we find that the electrostatically embedded three-body (EE-3B) method is able to reproduce conventionally calculated bond-breaking energies in a series of pentacoordinate and hexacoordinate zinc-containing systems with an average absolute error (averaged over 25 cases) of only 0.98 kcal/mol.

  2. Solidification and immobilization of MSWI fly ash through aluminate geopolymerization: Based on partial charge model analysis.

    Science.gov (United States)

    Zheng, Lei; Wang, Wei; Gao, Xingbao

    2016-12-01

    This study presents an integrated synopsis of the solidification and immobilization mechanisms of fly ash-based geopolymers. A rational analysis of the ion reactions involved in geopolymerization was conducted using the partial charge model (PCM). The following conclusions were obtained: (1) heavy metal cations cannot be immobilized as counter cations through exchange with Na(+); (2) isomorphous substitution of heavy metals in the geopolymer can be expected from the condensation reaction between the hydrolyzed heavy metal species and aluminosilicate; (3) the hydrolyzed species condensation could result in solidification and immobilization and be promoted by aluminates; and (4) a geopolymer with the highest immobilization and solidification efficiency can be obtained at an intermediate pH value. The partial charges on the framework of Si, Al, and O in the primary building blocks of aluminosilicate and heavy metal-doped aluminosilicate were confirmed through XPS and (29)Si NMR spectroscopy analyses. The effects of activator dosage and types on fly ash-based geopolymers were also investigated, and the results verify the PCM analysis. A geopolymer with the highest strength was produced at an intermediate alkaline dosage. Silicate or aluminate introduced into the activator improved the strength and immobilization efficiency, and aluminate exhibited better performance. Heavy metals bound to the exchangeable or acid-soluble fraction were transformed into aluminosilicate species during geopolymerization. Copyright © 2016. Published by Elsevier Ltd.

  3. Polarizable Force Fields and Polarizable Continuum Model: A Fluctuating Charges/PCM Approach. 1. Theory and Implementation.

    Science.gov (United States)

    Lipparini, Filippo; Barone, Vincenzo

    2011-11-08

    We present a combined fluctuating charges-polarizable continuum model approach to describe molecules in solution. Both static and dynamic approaches are discussed: analytical first and second derivatives are shown as well as an extended lagrangian for molecular dynamics simluations. In particular, we use the polarizable continuum model to provide nonperiodic boundary conditions for molecular dynamics simulations of aqueous solutions. The extended lagrangian method is extensively discussed, with specific reference to the fluctuating charge model, from a numerical point of view by means of several examples, and a rationalization of the behavior found is presented. Several prototypical applications are shown, especially regarding solvation of ions and polar molecules in water.

  4. Shallow velocity model in the area of Pozzo Pitarrone, Mt. Etna, from single station, array methods and borehole data

    Directory of Open Access Journals (Sweden)

    Luciano Zuccarello

    2016-09-01

    Full Text Available Seismic noise recorded by a temporary array installed around Pozzo Pitarrone, NE flank of Mt. Etna, have been analysed with several techniques. Single station HVSR method and SPAC array method have been applied to stationary seismic noise to investigate the local shallow structure. The inversion of dispersion curves produced a shear wave velocity model of the area reliable down to depth of about 130 m. A comparison of such model with the stratigraphic information available for the investigated area shows a good qualitative agreement. Taking advantage of a borehole station installed at 130 m depth, we could estimate also the P-wave velocity by comparing the borehole recordings of local earthquakes with the same event recorded at surface. Further insight on the P-wave velocity in the upper 130 m layer comes from the surface reflected wave observable in some cases at the borehole station. From this analysis we obtained an average P-wave velocity of about 1.2 km/s, compatible with the shear wave velocity found from the analysis of seismic noise.

  5. An Analysis of Air Force Avionic Test Station Utilization Using Q-Gert Modeling and Simulation.

    Science.gov (United States)

    1979-12-01

    repair times drawn from a Lognormal distribution [15]. As each LPU completes the service activity, the test station resource is freed and made available...71 make the availability of a spare LPU necessary before the failed LRU may be processed for repair. Pegular node-72 is neces- sary since in Q-GERT, a...of LRUs will begin and will continue until all queues are empty and the last LPU is repaired. At such time the simulation will stop since no

  6. Modeling of beam customization devices in the pencil beam splitting algorithm for heavy charged particle radiotherapy

    CERN Document Server

    Kanematsu, Nobuyuki

    2010-01-01

    Broad-beam-delivery methods use multiple devices to form a conformal field of heavy charged particles. To overcome an intrinsic difficulty of pencil-beam algorithms in dealing with fine lateral structure, we applied the pencil-beam-splitting algorithm to a beam-customization system conprised of multiple collimators and a range compensating filter. The pencil beams were initially defined at the range compensating filter with angular acceptance correction for the upstream collimators followed by the range compensation effects. They were individually transported with possible splitting near the downstream collimator edges. The dose distribution was calculated and compared with existing experimental data. The penumbra sizes for various collimator edges agreed between them to a submillimeter level. This beam-customization model will complete an accurate and efficient dose-calculation algorithm for treatment planning.

  7. Quantum phase transition between antiferromagnetic and charge order in the Hubbard-Holstein model

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Johannes [Max-Planck Institute for Solid State Research, Heisenbergstr.1, 70569 Stuttgart (Germany); Hewson, Alex C. [Department of Mathematics, Imperial College, London SW7 2AZ (United Kingdom)

    2010-03-15

    We explore the quantum phase transitions between two ordered states in the infinite dimensional Hubbard-Holstein model at half filling. Our study is based on the dynamical mean field theory (DMFT) combined with the numerical renormalization group (NRG), which allows us to handle both strong electron-electron and strong electron-phonon interactions. The transition line is characterized by an effective electron-electron interaction. Depending on this effective interaction and the phonon frequency {omega}{sub 0} one finds either a continuous transition or discontinuous transition. Here, the analysis focuses on the behavior of the system when the electron-electron repulsion U and the phonon-mediated attraction {lambda} are equal. We first discuss the adiabatic and antiadiabatic limiting cases. For finite {omega}{sub 0} we study the differences between the antiferromagnetic (AFM) and charge order, and find that when present the AFM state has a lower energy on the line. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  8. Extreme ultraviolet spectroscopy and atomic models of highly charged heavy ions in the Large Helical Device

    Science.gov (United States)

    Suzuki, C.; Murakami, I.; Koike, F.; Tamura, N.; Sakaue, H. A.; Morita, S.; Goto, M.; Kato, D.; Ohashi, H.; Higashiguchi, T.; Sudo, S.; O'Sullivan, G.

    2017-01-01

    We report recent results of extreme ultraviolet (EUV) spectroscopy of highly charged heavy ions in plasmas produced in the Large Helical Device (LHD). The LHD is an ideal source of experimental databases of EUV spectra because of high brightness and low opacity, combined with the availability of pellet injection systems and reliable diagnostic tools. The measured heavy elements include tungsten, tin, lanthanides and bismuth, which are motivated by ITER as well as a variety of plasma applications such as EUV lithography and biological microscopy. The observed spectral features drastically change between quasicontinuum and discrete depending on the plasma temperature, which leads to some new experimental identifications of spectral lines. We have developed collisional-radiative models for some of these ions based on the measurements. The atomic number dependence of the spectral feature is also discussed.

  9. Model Simulations of Charged Particles Multiplicity Distributions in the Forward Region for ALICE at LHC

    CERN Document Server

    Braun, M A; Kondratev, V P; Vechernin, V V

    1999-01-01

    We present results of Monte Carlo simulations of charged particles multiplicity distributions and ALICE background conditions in forward region for PbPb collisions at LHC.HIJING event generator [1] results are compared with predictions of Coloured String Fusion Model [2,3].Requirements to the Forward Multiplicity Detector for ALICE arising from these simulations are discussed (multiplicity range, resolution in multiplicity, granularity, timing resolution).References: [1] N.van Eijndhoven et al., ALICE/CERN 95-32, Internal Note 1996[2] M.Braun and C.Pajares, PHys. Rev. D47 (1993) 114-122[2] M.Braun and C.Pajares, PHys. Rev. C51 (1995) 879-889

  10. System dynamic model and charging control of lead-acid battery for stand-alone solar PV system

    KAUST Repository

    Huang, B.J.

    2010-05-01

    The lead-acid battery which is widely used in stand-alone solar system is easily damaged by a poor charging control which causes overcharging. The battery charging control is thus usually designed to stop charging after the overcharge point. This will reduce the storage energy capacity and reduce the service time in electricity supply. The design of charging control system however requires a good understanding of the system dynamic behaviour of the battery first. In the present study, a first-order system dynamics model of lead-acid battery at different operating points near the overcharge voltage was derived experimentally, from which a charging control system based on PI algorithm was developed using PWM charging technique. The feedback control system for battery charging after the overcharge point (14 V) was designed to compromise between the set-point response and the disturbance rejection. The experimental results show that the control system can suppress the battery voltage overshoot within 0.1 V when the solar irradiation is suddenly changed from 337 to 843 W/m2. A long-term outdoor test for a solar LED lighting system shows that the battery voltage never exceeded 14.1 V for the set point 14 V and the control system can prevent the battery from overcharging. The test result also indicates that the control system is able to increase the charged energy by 78%, as compared to the case that the charging stops after the overcharge point (14 V). © 2010 Elsevier Ltd. All rights reserved.

  11. Station Capacity

    DEFF Research Database (Denmark)

    Landex, Alex

    2011-01-01

    Stations are often limiting the capacity of railway networks. This is due to extra need of tracks when trains stand still, trains turning around, and conflicting train routes. Although stations are often the capacity bottlenecks, most capacity analysis methods focus on open line capacity. Therefore......, this paper presents methods to analyze station capacity. Four methods to analyze station capacity are developed. The first method is an adapted UIC 406 capacity method that can be used to analyze switch zones and platform tracks at stations that are not too complex. The second method examines the need...... the probability of conflicts and the minimum headway times into account. The last method analyzes how optimal platform tracks are used by examining the arrival and departure pattern of the trains. The developed methods can either be used separately to analyze specific characteristics of the capacity of a station...

  12. Large-eddy simulation of charged particle flows to model sandstorms

    Science.gov (United States)

    Rahman, Mustafa; Cheng, Wan; Samtaney, Ravi

    2016-11-01

    Intense electric fields and lightning have been observed in sandstorms. It is proposed to investigate the physical mechanisms essential for production and sustenance of large-scale electric fields in sandstorms. Our central hypothesis is that the turbulent transport of charged sand particles is a necessary condition to attain sustained large-scale electric fields in sandstorms. Our investigation relies on simulating turbulent two-phase (air and suspended sand particles) flows in which the flow of air is governed by the filtered Navier-Stokes equations with a subgrid-scale model in a Large-Eddy-Simulation setting, while dust particles are modeled using the Eulerian approach using a version of the Direct Quadrature Method of Moments. For the fluid phase, the LES of incompressible turbulent boundary layer employs stretched spiral vortex subgrid-scale model and a virtual wall model similar to the work of Cheng, Pullin & Samtaney. We will quantify the effects of different sand particle distributions, and turbulent intensities on the root-mean-square of the generated electric fields. Supported by KAUST OCRF under Award Number URF/1/1704-01-01. The supercomputer Shaheen at KAUST is used for all simulations.

  13. Characterization and Modeling of Received Signal Strength and Charging Time for Wireless Energy Transfer

    Directory of Open Access Journals (Sweden)

    Uthman Baroudi

    2015-01-01

    Full Text Available Wireless sensor networks can provide effective means for monitoring and controlling a wide range of applications. Recently, tremendous effort was directed towards devising sensors powered from ambient sources such as heat, wind, and vibration. Wireless energy transfer is another source that has attractive features that make it a promising candidate for supplying power to wireless sensor nodes. This paper is concerned with characterizing and modeling the charging time and received signal strength indicator for wireless energy transfer system. These parameters play a vital role in deciding the geometry of sensor network and the routing protocols to be deployed. The development of communication protocols for wireless-powered wireless sensor networks is also improved with the knowledge of such models. These two quantities were computed from data acquired at various coordinates of the harvester relative to a fixed position of RF energy source. Data was acquired for indoor and outdoor scenarios using the commercially available PowerCast energy harvester and evaluation board. Mathematical models for both indoor and outdoor environments were developed and analyzed. A few guidelines on how to use these models were suggested. Finally, the possibility of harvesting the energy from the ambient RF power to energize wireless sensor nodes was also investigated.

  14. Proton irradiation experiment for x-ray charge-coupled devices of the monitor of all-sky x-ray image mission onboard the international space station. 2. Degradation of dark current and identification of electron trap level

    CERN Document Server

    Miyata, E; Kamiyama, D

    2003-01-01

    We have investigated the radiation damage effects on a charge-coupled device (CCD) to be used for the Japanese X-ray mission, the monitor of all-sky X-ray image (MAXI), onboard the international space station (ISS). A temperature dependence of the dark current as a function of incremental dose is studied. We found that the protons having energy of >292 keV seriously increased the dark current of the devices. In order to improve the radiation tolerance of the devices, we have developed various device architectures to minimize the radiation damage in orbit. Among them, nitride oxide enables us to reduce the dark current significantly and therefore we adopted nitride oxide for the flight devices. We also compared the dark current of a device in operation and that out of operation during the proton irradiation. The dark current of the device in operation became twofold that out of operation, and we thus determined that devices would be turned off during the passage of the radiation belt. The temperature dependenc...

  15. Analysis of Electric Vehicle Charging Impact on the Electric Power Grid

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Zeming [Ming Hsieh Department of Electrical Engineering; Tian, Hao [Ming Hsieh Department of Electrical Engineering; Beshir, Mohammed J. [Ming Hsieh Department of Electrical Engineering; Vohra, Surendra [Los Angeles Department of Water and Power; Mazloomzadeh, Ali [Smart Utility Systems

    2016-09-24

    In order to evaluate the impact of electric vehicles (EVs) on the distribution grid and assess their potential benefits to the future smart grid, it is crucial to study the EV charging patterns and the usage charging station. Though EVs are not yet widely adopted nationwide, a valuable methodology to conduct such studies is the statistical analysis of real-world charging data. This paper presents actual EV charging behavior of 64 EVs (5 brands, 8 models) from EV users and charging stations at Los Angeles Department of Water and Power for more than one year. Twenty-four-hour EV charging load curves have been generated and studied for various load periods: daily, monthly, seasonally and yearly. Finally, the effect and impact of EV load on the California distribution network are evaluated at different EV penetration rates.

  16. Prediction of SO{sub 2} pollution incidents near a power station using partially linear models and an historical matrix of predictor-response vectors

    Energy Technology Data Exchange (ETDEWEB)

    Prada-Sanchez, J.M.; Febrero-Bande, M.; Gonzalez-Manteiga, W. [Universidad de Santiago de Compostela, Dept. de Estadistica e Investigacion Operativa, Santiago de Compostela (Spain); Costos-Yanez, T. [Universidad de Vigo, Dept. de Estadistica e Investigacion Operativa, Orense (Spain); Bermudez-Cela, J.L.; Lucas-Dominguez, T. [Laboratorio, Central Termica de As Pontes, La Coruna (Spain)

    2000-07-01

    Atmospheric SO{sub 2} concentrations at sampling stations near the fossil fuel fired power station at As Pontes (La Coruna, Spain) were predicted using a model for the corresponding time series consisting of a self-explicative term and a linear combination of exogenous variables. In a supplementary simulation study, models of this kind behaved better than the corresponding pure self-explicative or pure linear regression models. (Author)

  17. Amtrak Stations

    Data.gov (United States)

    Department of Homeland Security — Updated database of the Federal Railroad Administration's (FRA) Amtrak Station database. This database is a geographic data set containing Amtrak intercity railroad...

  18. Modeling the binding of benzenecarboxylates by goethite: The ligand and charge distribution model

    NARCIS (Netherlands)

    Filius, J.D.; Meeussen, J.C.L.; Hiemstra, T.; Riemsdijk, van W.H.

    2001-01-01

    A heterogeneous complexation model approach has been developed to describe the adsorption of large organic molecules by goethite taking the full speciation of the adsorbed molecules into account. The essence of the model is the calculation of the mean mode of an adsorbed organic molecule, defined by

  19. Modeling the adsorption of weak organic acids on goethite : the ligand and charge distribution model

    NARCIS (Netherlands)

    Filius, J.D.

    2001-01-01

    A detailed study is presented in which the CD-MUSIC modeling approach is used in a new modeling approach that can describe the binding of large organic molecules by metal (hydr)oxides taking the full speciation of the adsorbed molecule into account. Batch equilibration experiments were

  20. Research on the modeling of the impedance match bond at station track circuit in Chinese high-speed railway

    Directory of Open Access Journals (Sweden)

    Shiwu Yang

    2015-11-01

    Full Text Available Frequency-shift keying audio jointless track circuit is used in high-speed railway in China. However, within the station, track circuit with mechanical insulation is applied. In complex circuit network of electrified railway station, impedance match bond is designed to ensure the normal operation of the track circuit and the protection of strong traction current interference. As a combination of strong and weak electricity components of track circuit, impedance match bond is both the part of the loop of the traction current and the part of the transmission line of track circuit, playing a very critical role in the electrified railway. The structure of impedance match bond is more complex than traditional impedance transformer, including the transformer with larger air-gap, LC resonance circuit for power frequency filtering, and components to enhance the signal frequency. Modeling on impedance match bond and study about the four-terminal network parameters of impedance match bond are in favor of the following two aspects: modeling of the overall traction current and calculation of track circuit working condition. By applying the transformer equivalent circuit model and combination of testing and calculation, the accurate model of impedance match bond is constructed and verified. Finally, for ease of track circuit calculation, four-terminal network model of impedance match bond under different signal carrier frequencies is presented.

  1. Electrochemical Surface Potential due to Classical Point Charge Models Drives Anion Adsorption to the Air-Water Interface

    Energy Technology Data Exchange (ETDEWEB)

    Baer, Marcel D.; Stern, Abraham C.; Levin, Yan; Tobias, Douglas J.; Mundy, Christopher J.

    2012-06-07

    Herein, we present research that suggests that the underlying physics that drive simple empirical models of anions (e.g. point charge, no polarization) to the air-water interface, with water described by SPC/E, or related partial charge models is different than when both ions and water are modeled with quantum mechanical based interactions. Specifically, we will show that the driving force of ions to the air-water interface for point charge models results from both cavitation and the negative electrochemical surface potential. We will demonstrate that we can fully characterize the role of the free energy due to the electrochemical surface potential computed from simple empirical models and its role in ionic adsorption within the context of dielectric continuum theory (DCT). Our research suggests that a significant part of the electrochemical surface potential in empirical models appears to be an artifact of the failure of point charge models in the vicinity of a broken symmetry. This work was supported by the U.S. Department of Energy‘s (DOE) Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences. Pacific Northwest National Laboratory (PNNL) is operated for the Department of Energy by Battelle.

  2. Charge carrier transport in molecularly doped polycarbonate as a test case for the dipolar glass model.

    Science.gov (United States)

    Novikov, S V; Tyutnev, A P

    2013-03-14

    We present the results of Monte Carlo simulations of the charge carrier transport in a disordered molecular system containing spatial and energetic disorders using the dipolar glass model. Model parameters of the material were chosen to fit a typical polar organic photoconductor polycarbonate doped with 30% of aromatic hydrazone, whose transport properties are well documented in literature. Simulated carrier mobility demonstrates a usual Poole-Frenkel field dependence and its slope is very close to the experimental value without using any adjustable parameter. At room temperature transients are universal with respect to the electric field and transport layer thickness. At the same time, carrier mobility does not depend on the layer thickness and transients develop a well-defined plateau where the current does not depend on time, thus demonstrating a non-dispersive transport regime. Tails of the transients decay as power law with the exponent close to -2. This particular feature indicates that transients are close to the boundary between dispersive and non-dispersive transport regimes. Shapes of the simulated transients are in very good agreement with the experimental ones. In summary, we provide a first verification of a self-consistency of the dipolar glass transport model, where major transport parameters, extracted from the experimental transport data, are then used in the transport simulation, and the resulting mobility field dependence and transients are in very good agreement with the initial experimental data.

  3. Choice of rainfall inputs for event-based rainfall-runoff modeling in a catchment with multiple rainfall stations using data-driven techniques

    Science.gov (United States)

    Chang, Tak Kwin; Talei, Amin; Alaghmand, Sina; Ooi, Melanie Po-Leen

    2017-02-01

    Input selection for data-driven rainfall-runoff models is an important task as these models find the relationship between rainfall and runoff by direct mapping of inputs to output. In this study, two different input selection methods were used: cross-correlation analysis (CCA), and a combination of mutual information and cross-correlation analyses (MICCA). Selected inputs were used to develop adaptive network-based fuzzy inference system (ANFIS) in Sungai Kayu Ara basin, Selangor, Malaysia. The study catchment has 10 rainfall stations and one discharge station located at the outlet of the catchment. A total of 24 rainfall-runoff events (10-min interval) from 1996 to 2004 were selected from which 18 events were used for training and the remaining 6 were reserved for validating (testing) the models. The results of ANFIS models then were compared against the ones obtained by conceptual model HEC-HMS. The CCA and MICCA methods selected the rainfall inputs only from 2 (stations 1 and 5) and 3 (stations 1, 3, and 5) rainfall stations, respectively. ANFIS model developed based on MICCA inputs (ANFIS-MICCA) performed slightly better than the one developed based on CCA inputs (ANFIS-CCA). ANFIS-CCA and ANFIS-MICCA were able to perform comparably to HEC-HMS model where rainfall data of all 10 stations had been used; however, in peak estimation, ANFIS-MICCA was the best model. The sensitivity analysis on HEC-HMS was conducted by recalibrating the model by using the same selected rainfall stations for ANFIS. It was concluded that HEC-HMS model performance deteriorates if the number of rainfall stations reduces. In general, ANFIS was found to be a reliable alternative for HEC-HMS in cases whereby not all rainfall stations are functioning. This study showed that the selected stations have received the highest total rain and rainfall intensity (stations 3 and 5). Moreover, the contributing rainfall stations selected by CCA and MICCA were found to be located near the outlet of

  4. Reliability and acceptability of a five-station multiple mini-interview model for residency program recruitment

    Directory of Open Access Journals (Sweden)

    Julian Diaz Fraga

    2013-12-01

    Full Text Available Background: Standard interviews are used by most residency programs in the United States for assessment of aptitude of the non-cognitive competencies, but variability of interviewer skill, interviewer bias, interviewer leniency or stringency, and context specificity limit reliability. Aim: To investigate reliability and acceptability of five-station multiple mini-interview (MMI model for resident selection into an internal medicine residency program in the United States. Setting: One independent academic medical center. Participants: Two hundred and thirty-seven applicants and 17 faculty interviewers. Program description: Five, 10-min MMI stations with five different interviewers blinded to the candidate's records and one traditional 20-min interview with the program director. Candidates were rated on two items: interpersonal and communication skills, and overall performance. Program evaluation: Generalizability data showed that the reliability of our process was high (>0.9. The results of anonymous surveys demonstrated that both applicants and interviewers consider the MMI as a fair and more effective tool to evaluate non-cognitive traits, and prefer the MMI to standard interviews. Discussion: The MMI process for residency interviews can generate reliable interview results using only five stations, and it is acceptable and preferred over standard interview modalities by the applicants and faculty members of one US residency program.

  5. Importance of Accurate Computation of Secondary Electron Emission for ModelingSpacecraft Charging

    OpenAIRE

    Clerc, Sebastien; Dennison, JR

    2005-01-01

    The secondary electron yield is a critical process in establishing the charge balance in spacecraft charging and the subsequent determination of the equilibrium potential. Spacecraft charging codes use a parameterized expression for the secondary electron yield δ(Eo) as a function of incident electron energy, Eo. A critical step in accurately characterizing a particular spacecraft material is establishing the most efficient and accurate way to determine the fitting parameters in terms of the ...

  6. Otitis Media in a New Mouse Model for CHARGE Syndrome with a Deletion in the Chd7 Gene

    Science.gov (United States)

    Tian, Cong; Yu, Heping; Yang, Bin; Han, Fengchan; Zheng, Ye; Bartels, Cynthia F.; Schelling, Deborah; Arnold, James E.; Scacheri, Peter C.; Zheng, Qing Yin

    2012-01-01

    Otitis media is a middle ear disease common in children under three years old. Otitis media can occur in normal individuals with no other symptoms or syndromes, but it is often seen in individuals clinically diagnosed with genetic diseases such as CHARGE syndrome, a complex genetic disease caused by mutation in the Chd7 gene and characterized by multiple birth defects. Although otitis media is common in human CHARGE syndrome patients, it has not been reported in mouse models of CHARGE syndrome. In this study, we report a mouse model with a spontaneous deletion mutation in the Chd7 gene and with chronic otitis media of early onset age accompanied by hearing loss. These mice also exhibit morphological alteration in the Eustachian tubes, dysregulation of epithelial proliferation, and decreased density of middle ear cilia. Gene expression profiling revealed up-regulation of Muc5ac, Muc5b and Tgf-β1 transcripts, the products of which are involved in mucin production and TGF pathway regulation. This is the first mouse model of CHARGE syndrome reported to show otitis media with effusion and it will be valuable for studying the etiology of otitis media and other symptoms in CHARGE syndrome. PMID:22539951

  7. Mechanisms of nanoparticle internalization and transport across an intestinal epithelial cell model: effect of size and surface charge.

    Science.gov (United States)

    Bannunah, Azzah M; Vllasaliu, Driton; Lord, Jennie; Stolnik, Snjezana

    2014-12-01

    This study investigated the effect of nanoparticle size (50 and 100 nm) and surface charge on their interaction with Caco-2 monolayers as a model of the intestinal epithelium, including cell internalization pathways and the level of transepithelial transport. Initially, toxicity assays showed that cell viability and cell membrane integrity were dependent on the surface charge and applied mass, number, and total surface area of nanoparticles, as tested in two epithelial cell lines, colon carcinoma Caco-2 and airway Calu-3. This also identified suitable nanoparticle concentrations for subsequent cell uptake experiments. Nanoparticle application at doses below half maximal effective concentration (EC₅₀) revealed that the transport efficiency (ratio of transport to cell uptake) across Caco-2 cell monolayers is significantly higher for negatively charged nanoparticles compared to their positively charged counterparts (of similar size), despite the higher level of internalization of positively charged systems. Cell internalization pathways were hence probed using a panel of pharmacological inhibitors aiming to establish whether the discrepancy in transport efficiency is due to different uptake and transport pathways. Vesicular trans-monolayer transport for both positively and negatively charged nanoparticles was confirmed via inhibition of dynamin (by dynasore) and microtubule network (via nocodazole), which significantly reduced the transport of both nanoparticle systems. For positively charged nanoparticles a significant decrease in internalization and transport (46% and 37%, respectively) occurred in the presence of a clathrin pathway inhibitor (chlorpromazine), macropinocytosis inhibition (42%; achieved by 5-(N-ethyl-N-isopropyi)-amiloride), and under cholesterol depletion (38%; via methyl-β-cyclodextrin), but remained unaffected by the inhibition of lipid raft associated uptake (caveolae) by genistein. On the contrary, the most prominent reduction in

  8. Modelling SMOS brightness temperature by use of coupled SVAT and radiative transfer models over the Valencia Anchor Station

    Science.gov (United States)

    Juglea, S.; Kerr, Y.; Mialon, A.; Lopez-Baeza, E.; Cano, A.; Calvet, J. C.; Albitar, A.; Wigneron, J. P.

    2009-04-01

    Soil moisture is a key variable that controls water and heat energy interactions occurring at the land atmosphere interface. This parameter, very important for the weather and climate modelling, is not well monitored at a global scale. A number of experiments have shown the high potential of L-band microwave radiometry for monitoring surface soil moisture. In this context, the SMOS (Soil Moisture and Ocean Salinity) mission was designed to observe soil moisture over continental surfaces as well as ocean salinity. Due to be launched in summer 2009, it will provide global soil moisture maps every 3 days at least, with an average spatial resolution of 40 km x 40 km. The VAS (Valencia Anchor Station) experimental site, in Spain, is a cornerstone of the SMOS Cal/Val plan. It is a semiarid environment and is characterized by an extensive set of measurements at different levels (in the atmosphere and in the soil) in order to derive surface energy fluxes. In the framework of SMOS preparation, the research presented here deals with the use of surface variables from the VAS site to simulate passive microwave brightness temperature so as to have Satellite "match ups" for CalVal and to test retrieval algorithms. First, ground and meteorological measurements from the VAS site are used to simulate soil moisture using a Soil-Vegetation-Atmosphere-Transfer (SVAT) model (ISBA) from Météo France. In order to validate this approach, a point to point comparison with ground measurements has been done. We obtain a very good agreement between the simulated and measured soil moisture and we find that, as expected, the simulated soil moisture is mostly driven by precipitation patterns. Then, we propose a spatialization method using all the available data in order to have soil moisture estimates representative of a SMOS pixel. The results are compared with remotely sensed data such as soil moisture from AMSR-E. An amplitude difference between both soil moisture data is observed but also a

  9. Enhancing the estimation accuracy in low state-of-charge area: A novel onboard battery model through surface state of charge determination

    Science.gov (United States)

    Ouyang, Minggao; Liu, Guangming; Lu, Languang; Li, Jianqiu; Han, Xuebing

    2014-12-01

    In order to predict the battery remaining discharge energy in electric vehicles, an accurate onboard battery model is needed for the terminal voltage and state of charge (SOC) estimation in the whole SOC range. However, the commonly-used equivalent circuit model (ECM) provides limited accuracy in low-SOC area, which hinders the full use of battery remaining energy. To improve the low-SOC-area performance, this paper presents an extended equivalent circuit model (EECM) based on single-particle electrochemical model. In EECM, the solid-phase diffusion process is represented by the SOC difference within the electrode particle, and the terminal voltage is determined by the surface SOC (SOCsurf) representing the lithium concentration at the particle surface. Based on a large-format lithium-ion battery, the voltage estimation performance of ECM and EECM is compared in the entire SOC range (0-100%) under different load profiles, and the genetic algorithm is implemented in model parameterization. Results imply that the EECM could reduce the voltage error by more than 50% in low-SOC area. The SOC estimation accuracy is then discussed employing the extended Kalman filter, and the EECM also exhibits significant advantage. As a result, the EECM is very potential for real-time applications to enhance the voltage and SOC estimation precision especially for low-SOC cases.

  10. A neural network-based foF2 model for a single station in the polar cap

    Science.gov (United States)

    Athieno, R.; Jayachandran, P. T.; Themens, D. R.

    2017-06-01

    A neural network (NN) model has been developed for the critical frequency of the F2 layer (foF2) at Resolute (74.70°N, 265.10°E) using data obtained from the Space Physics Interactive Data Resource (no longer available) for the period between 1975 and 1995. This model is a first step toward addressing the discrepancies of the International Reference Ionosphere (IRI) foF2 or peak electron density (NmF2) at high latitudes recently presented by Themens et al. (2014). The performance of the NN model has been evaluated using foF2 data obtained from the Canadian Advanced Digital Ionosonde at Resolute (74.75°N, 265.00°E) for the period between 2009 and 2013, in comparison with the IRI predictions. The 2012 version and the International Union of Radio Science option of IRI have been used. The NN nighttime monthly median foF2 variation demonstrates good agreement with observations compared to the IRI. The NN model is able to reproduce the enhancements in foF2 during the equinoxes and also shows an improvement during disturbed days. Root mean square errors were computed between hourly and monthly median model predictions and observations, and on the whole, the NN model seems to perform better during low solar activity and the equinoxes. The NN model shows an improvement in performance on average by 26.638% for hourly foF2 and 32.636% for monthly median foF2, compared to 7.877% obtained for the same station by the most recent NN model that attempted to predict foF2 at a polar cap station (Oyeyemi and Poole, 2005).

  11. A relativistic self-consistent model for studying enhancement of space charge limited emission due to counter-streaming ions

    Science.gov (United States)

    Lin, M. C.; Verboncoeur, J.

    2016-10-01

    A maximum electron current transmitted through a planar diode gap is limited by space charge of electrons dwelling across the gap region, the so called space charge limited (SCL) emission. By introducing a counter-streaming ion flow to neutralize the electron charge density, the SCL emission can be dramatically raised, so electron current transmission gets enhanced. In this work, we have developed a relativistic self-consistent model for studying the enhancement of maximum transmission by a counter-streaming ion current. The maximum enhancement is found when the ion effect is saturated, as shown analytically. The solutions in non-relativistic, intermediate, and ultra-relativistic regimes are obtained and verified with 1-D particle-in-cell simulations. This self-consistent model is general and can also serve as a comparison for verification of simulation codes, as well as extension to higher dimensions.

  12. A multi-physical model for charge and mass transport in a flexible ionic polymer sensor

    Science.gov (United States)

    Zhu, Zicai; Asaka, Kinji; Takagi, Kentaro; Aabloo, Alvo; Horiuchi, Tetsuya

    2016-04-01

    An ionic polymer material can generate electrical potential and function as a bio-sensor under a non-uniform deformation. Ionic polymer-metal composite (IPMC) is a typical flexible ionic polymer sensor material. A multi-physical sensing model is presented at first based on the same physical equations in the physical model for IPMC actuator we obtained before. Under an applied bending deformation, water and cation migrate to the direction of outside electrode immediately. Redistribution of cations causes an electrical potential difference between two electrodes. The cation migration is strongly restrained by the generated electrical potential. And the migrated cations will move back to the inner electrode under the concentration diffusion effect and lead to a relaxation of electrical potential. In the whole sensing process, transport and redistribution of charge and mass are revealed along the thickness direction by numerical analysis. The sensing process is a revised physical process of the actuation, however, the transport properties are quite different from those of the later. And the effective dielectric constant of IPMC, which is related to the morphology of the electrode-ionic polymer interface, is proved to have little relation with the sensing amplitude. All the conclusions are significant for ionic polymer sensing material design.

  13. Photoinduced charge-order melting dynamics in a one-dimensional interacting Holstein model

    Science.gov (United States)

    Hashimoto, Hiroshi; Ishihara, Sumio

    2017-07-01

    Transient quantum dynamics in an interacting fermion-phonon system are investigated with a focus on a charge order (CO) melting after a short optical-pulse irradiation and the roles of the quantum phonons in the transient dynamics. A spinless-fermion model in a one-dimensional chain coupled with local phonons is analyzed numerically. The infinite time-evolving block decimation algorithm is adopted as a reliable numerical method for one-dimensional quantum many-body systems. Numerical results for the photoinduced CO melting dynamics without phonons are well interpreted by the soliton picture for the CO domains. This interpretation is confirmed by numerical simulation of an artificial local excitation and the classical soliton model. In the case of large phonon frequencies corresponding to the antiadiabatic condition, CO melting is induced by propagations of the polaronic solitons with the renormalized soliton velocity. On the other hand, in the case of small phonon frequencies corresponding to the adiabatic condition, the first stage of the CO melting dynamics occurs due to the energy transfer from the fermionic to phononic systems, and the second stage is brought about by the soliton motions around the bottom of the soliton band. The analyses provide a standard reference for photoinduced CO melting dynamics in one-dimensional many-body quantum systems.

  14. Development of a computer model to predict platform station keeping requirements in the Gulf of Mexico using remote sensing data

    Science.gov (United States)

    Barber, Bryan; Kahn, Laura; Wong, David

    1990-01-01

    Offshore operations such as oil drilling and radar monitoring require semisubmersible platforms to remain stationary at specific locations in the Gulf of Mexico. Ocean currents, wind, and waves in the Gulf of Mexico tend to move platforms away from their desired locations. A computer model was created to predict the station keeping requirements of a platform. The computer simulation uses remote sensing data from satellites and buoys as input. A background of the project, alternate approaches to the project, and the details of the simulation are presented.

  15. Location Design of Electric Vehicle Charging Facilities: A Path-Distance Constrained Stochastic User Equilibrium Approach

    Directory of Open Access Journals (Sweden)

    Wentao Jing

    2017-01-01

    Full Text Available Location of public charging stations, range limit, and long battery-charging time inevitably affect drivers’ path choice behavior and equilibrium flows of battery electric vehicles (BEVs in a transportation network. This study investigates the effect of the location of BEVs public charging facilities on a network with mixed conventional gasoline vehicles (GVs and BEVs. These two types of vehicles are distinguished from each other in terms of travel cost composition and distance limit. A bilevel model is developed to address this problem. In the upper level, the objective is to maximize coverage of BEV flows by locating a given number of charging stations on road segments considering budget constraints. A mixed-integer nonlinear program is proposed to formulate this model. A simple equilibrium-based heuristic algorithm is developed to obtain the solution. Finally, two numerical tests are presented to demonstrate applicability of the proposed model and feasibility and effectiveness of the solution algorithm. The results demonstrate that the equilibrium traffic flows are affected by charging speed, range limit, and charging facilities’ utility and that BEV drivers incline to choose the route with charging stations and less charging time.

  16. Irradiation of Neurons with High-Energy Charged Particles: An In Silico Modeling Approach.

    Science.gov (United States)

    Alp, Murat; Parihar, Vipan K; Limoli, Charles L; Cucinotta, Francis A

    2015-08-01

    In this work, a stochastic computational model of microscopic energy deposition events is used to study for the first time damage to irradiated neuronal cells of the mouse hippocampus. An extensive library of radiation tracks for different particle types is created to score energy deposition in small voxels and volume segments describing a neuron's morphology that later are sampled for given particle fluence or dose. Methods included the construction of in silico mouse hippocampal granule cells from neuromorpho.org with spine and filopodia segments stochastically distributed along the dendritic branches. The model is tested with high-energy (56)Fe, (12)C, and (1)H particles and electrons. Results indicate that the tree-like structure of the neuronal morphology and the microscopic dose deposition of distinct particles may lead to different outcomes when cellular injury is assessed, leading to differences in structural damage for the same absorbed dose. The significance of the microscopic dose in neuron components is to introduce specific local and global modes of cellular injury that likely contribute to spine, filopodia, and dendrite pruning, impacting cognition and possibly the collapse of the neuron. Results show that the heterogeneity of heavy particle tracks at low doses, compared to the more uniform dose distribution of electrons, juxtaposed with neuron morphology make it necessary to model the spatial dose painting for specific neuronal components. Going forward, this work can directly support the development of biophysical models of the modifications of spine and dendritic morphology observed after low dose charged particle irradiation by providing accurate descriptions of the underlying physical insults to complex neuron structures at the nano-meter scale.

  17. Modeling of temporal variation of very low frequency radio waves over long paths as observed from Indian Antarctic stations

    Science.gov (United States)

    Sasmal, Sudipta; Basak, Tamal; Chakraborty, Suman; Palit, Sourav; Chakrabarti, Sandip K.

    2017-07-01

    Characteristics of very low frequency (VLF) signal depends on solar illumination across the propagation path. For a long path, solar zenith angle varies widely over the path and this has a significant influence on the propagation characteristics. To study the effect, Indian Centre for Space Physics participated in the 27th and 35th Scientific Expedition to Antarctica. VLF signals transmitted from the transmitters, namely, VTX (18.2 kHz), Vijayanarayanam, India, and NWC (19.8 kHz), North West Cape, Australia, were recorded simultaneously at Indian permanent stations Maitri and Bharati having respective geographic coordinates 70.75°S, 11.67°E, and 69.4°S, 76.17°E. A very stable diurnal variation of the signal has been obtained from both the stations. We reproduced the signal variations of VLF signal using solar zenith angle model coupled with long wavelength propagation capability (LWPC) code. We divided the whole path into several segments and computed the solar zenith angle (χ) profile. We assumed a linear relationship between the Wait's exponential model parameters effective reflection height (h'), steepness parameter (β), and solar zenith angle. The h' and β values were later used in the LWPC code to obtain the VLF signal amplitude at a particular time. The same procedure was repeated to obtain the whole day signal. Nature of the whole day signal variation from the theoretical modeling is also found to match with our observation to some extent.

  18. Computational modeling of chemical reactions and interstitial growth and remodeling involving charged solutes and solid-bound molecules.

    Science.gov (United States)

    Ateshian, Gerard A; Nims, Robert J; Maas, Steve; Weiss, Jeffrey A

    2014-10-01

    Mechanobiological processes are rooted in mechanics and chemistry, and such processes may be modeled in a framework that couples their governing equations starting from fundamental principles. In many biological applications, the reactants and products of chemical reactions may be electrically charged, and these charge effects may produce driving forces and constraints that significantly influence outcomes. In this study, a novel formulation and computational implementation are presented for modeling chemical reactions in biological tissues that involve charged solutes and solid-bound molecules within a deformable porous hydrated solid matrix, coupling mechanics with chemistry while accounting for electric charges. The deposition or removal of solid-bound molecules contributes to the growth and remodeling of the solid matrix; in particular, volumetric growth may be driven by Donnan osmotic swelling, resulting from charged molecular species fixed to the solid matrix. This formulation incorporates the state of strain as a state variable in the production rate of chemical reactions, explicitly tying chemistry with mechanics for the purpose of modeling mechanobiology. To achieve these objectives, this treatment identifies the specific theoretical and computational challenges faced in modeling complex systems of interacting neutral and charged constituents while accommodating any number of simultaneous reactions where reactants and products may be modeled explicitly or implicitly. Several finite element verification problems are shown to agree with closed-form analytical solutions. An illustrative tissue engineering analysis demonstrates tissue growth and swelling resulting from the deposition of chondroitin sulfate, a charged solid-bound molecular species. This implementation is released in the open-source program FEBio ( www.febio.org ). The availability of this framework may be particularly beneficial to optimizing tissue engineering culture systems by examining the

  19. [STEM on Station Education

    Science.gov (United States)

    Lundebjerg, Kristen

    2016-01-01

    The STEM on Station team is part of Education which is part of the External Relations organization (ERO). ERO has traditional goals based around BHAG (Big Hairy Audacious Goal). The BHAG model is simplified to a saying: Everything we do stimulates actions by others to advance human space exploration. The STEM on Station education initiate is a project focused on bringing off the earth research and learning into classrooms. Educational resources such as lesson plans, activities to connect with the space station and STEM related contests are available and hosted by the STEM on Station team along with their partners such as Texas Instruments. These educational activities engage teachers and students in the current happenings aboard the international space station, inspiring the next generation of space explorers.

  20. Pairs of charged heavy fermions from an $SU(3)_{L}(-)U(1)_{N}$ model at $e^{+}e^{-}$ colliders

    CERN Document Server

    Cieza-Montalvo, J E; 10.1103/PhysRevD.67.075022

    2003-01-01

    We investigate the production, backgrounds, and signatures of pairs of charged heavy fermions using the SU(3)/sub L/(-)U(1)/sub N/ electroweak model in e/sup +/e/sup -/ colliders (Next Linear Collider and CERN Linear Collider). We also analyze the indirect evidence for a boson Z'. (23 refs).

  1. Angular sensitivity of modeled scientific silicon charge-coupled devices to initial electron direction

    Energy Technology Data Exchange (ETDEWEB)

    Plimley, Brian, E-mail: brian.plimley@gmail.com [Nuclear Engineering Department, University of California, Berkeley, CA (United States); Coffer, Amy; Zhang, Yigong [Nuclear Engineering Department, University of California, Berkeley, CA (United States); Vetter, Kai [Nuclear Engineering Department, University of California, Berkeley, CA (United States); Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

    2016-08-11

    Previously, scientific silicon charge-coupled devices (CCDs) with 10.5-μm pixel pitch and a thick (650 μm), fully depleted bulk have been used to measure gamma-ray-induced fast electrons and demonstrate electron track Compton imaging. A model of the response of this CCD was also developed and benchmarked to experiment using Monte Carlo electron tracks. We now examine the trade-off in pixel pitch and electronic noise. We extend our CCD response model to different pixel pitch and readout noise per pixel, including pixel pitch of 2.5 μm, 5 μm, 10.5 μm, 20 μm, and 40 μm, and readout noise from 0 eV/pixel to 2 keV/pixel for 10.5 μm pixel pitch. The CCD images generated by this model using simulated electron tracks are processed by our trajectory reconstruction algorithm. The performance of the reconstruction algorithm defines the expected angular sensitivity as a function of electron energy, CCD pixel pitch, and readout noise per pixel. Results show that our existing pixel pitch of 10.5 μm is near optimal for our approach, because smaller pixels add little new information but are subject to greater statistical noise. In addition, we measured the readout noise per pixel for two different device temperatures in order to estimate the effect of temperature on the reconstruction algorithm performance, although the readout is not optimized for higher temperatures. The noise in our device at 240 K increases the FWHM of angular measurement error by no more than a factor of 2, from 26° to 49° FWHM for electrons between 425 keV and 480 keV. Therefore, a CCD could be used for electron-track-based imaging in a Peltier-cooled device.

  2. Numerical modeling on homogeneous charge compression ignition combustion engine fueled by diesel-ethanol blends

    Directory of Open Access Journals (Sweden)

    Hanafi H.

    2016-01-01

    Full Text Available This paper investigates the performance and emission characteristics of HCCI engines fueled with oxygenated fuels (ethanol blend. A modeling study was conducted to investigate the impact of ethanol addition on the performance, combustion and emission characteristics of a Homogeneous Charge Compression Ignition (HCCI engine fueled by diesel. One dimensional simulation was conducted using the renowned commercial software for diesel and its blend fuels with 5% (E5 and 10% ethanol (E10 (in vol. under full load condition at variable engine speed ranging from 1000 to 2750 rpm with 250 rpm increment. The model was then validated with other researcher’s experimental result. Model consists of intake and exhaust systems, cylinder, head, valves and port geometries. Performance tests were conducted for volumetric efficiency, brake engine torque, brake power, brake mean effective pressure, brake specific fuel consumption, and brake thermal efficiency, while exhaust emissions were analyzed for carbon monoxide (CO and unburned hydrocarbons (HC. The results showed that blending diesel with ethanol increases the volumetric efficiency, brake specific fuel consumption and brake thermal efficiency, while it decreases brake engine torque, brake power and brake mean effective pressure. In term of emission characteristics, the CO emissions concentrations in the engine exhaust decrease significantly with ethanol as additive. But for HC emission, its concentration increase when apply in high engine speed. In conclusion, using Ethanol as fuel additive blend with Diesel operating in HCCI shows a good result in term of performance and emission in low speed but not recommended to use in high speed engine. Ethanol-diesel blends need to researched more to make it commercially useable.

  3. Research on the application of PPP model in the Chinese construction and operation of new energy vehicle charging facilities

    Science.gov (United States)

    Zhu, Liping

    2017-05-01

    New energy car charging equipment is the development and popularization of new energy vehicles. It has the nature of quasi-public goods. Due to the large number of construction projects, wide distribution, big investment, it needs huge sums of money. PPP mode is a new financing model and has the inherent driving force to lead the idea the technology and the system innovation. The government and the social subject cooperate on the basis of the spirit of contract thus achieve benefit sharing. This mode effectively improve the operation of new energy vehicle charging facilities operating efficiency

  4. The tight binding model study of the role of anisotropic AFM spin ordering in the charge ordered CMR manganites

    Science.gov (United States)

    Kar, J. K.; Panda, Saswati; Rout, G. C.

    2017-05-01

    We propose here a tight binding model study of the interplay between charge and spin orderings in the CMR manganites taking anisotropic effect due to electron hoppings and spin exchanges. The Hamiltonian consists of the kinetic energies of eg and t2g electrons of manganese ion. It further includes double exchange and Heisenberg interactions. The charge density wave interaction (CDW) describes an extra mechanism for the insulating character of the system. The CDW gap and spin parameters are calculated using Zubarev's Green's function technique and computed self-consistently. The results are reported in this communication.

  5. Structure of dark matter halos in warm dark matter models and in models with long-lived charged massive particles

    Energy Technology Data Exchange (ETDEWEB)

    Kamada, Ayuki; Yoshida, Naoki [Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Kohri, Kazunori [Cosmophysics Group, Theory Center, IPNS, KEK, Tsukuba, 305-0801 (Japan); Takahashi, Tomo, E-mail: ayuki.kamada@ipmu.jp, E-mail: naoki.yoshida@phys.s.u-tokyo.ac.jp, E-mail: kohri@post.kek.jp, E-mail: tomot@cc.saga-u.ac.jp [Department of Physics, Saga University, Saga 840-8502 (Japan)

    2013-03-01

    We study the formation of non-linear structures in warm dark matter (WDM) models and in a long-lived charged massive particle (CHAMP) model. CHAMPs with a decay lifetime of about 1 yr induce characteristic suppression in the matter power spectrum at subgalactic scales through acoustic oscillations in the thermal background. We explore structure formation in such a model. We also study three WDM models, where the dark matter particles are produced through the following mechanisms: i) WDM particles are produced in the thermal background and then kinematically decoupled; ii) WDM particles are fermions produced by the decay of thermal heavy bosons; and iii) WDM particles are produced by the decay of non-relativistic heavy particles. We show that the linear matter power spectra for the three models are all characterised by the comoving Jeans scale at the matter-radiation equality. Furthermore, we can also describe the linear matter power spectrum for the long-lived CHAMP model in terms of a suitably defined characteristic cut-off scale k{sub Ch}, similarly to the WDM models. We perform large cosmological N-body simulations to study the non-linear growth of structures in these four models. We compare the halo mass functions, the subhalo mass functions, and the radial distributions of subhalos in simulated Milky Way-size halos. For the characteristic cut-off scale k{sub cut} = 51 h Mpc{sup −1}, the subhalo abundance ( ∼ 10{sup 9}M{sub sun}) is suppressed by a factor of ∼ 10 compared with the standard ΛCDM model. We then study the models with k{sub cut} ≅ 51, 410, 820 h Mpc{sup −1}, and confirm that the halo and the subhalo abundances and the radial distributions of subhalos are indeed similar between the different WDM models and the long-lived CHAMP model. The result suggests that the cut-off scale k{sub cut} not only characterises the linear power spectra but also can be used to predict the non-linear clustering properties. The radial distribution of subhalos

  6. Regional travel-time residual studies and station correction from 1-D velocity models for some stations around Peninsular Malaysia and Singapore

    OpenAIRE

    Abel U. Osagie; Nawawi, Mohd.; Khalil, Amin Esmail; Abdullah, Khiruddin

    2016-01-01

    We have investigated the average P-wave travel-time residuals for some stations around Southern Thailand, Peninsular Malaysia and Singapore at regional distances. Six years (January, 2010–December, 2015) record of events from central and northern Sumatra was obtained from the digital seismic archives of Integrated Research Institute for Seismology (IRIS). The criteria used for the data selection are designed to be above the magnitude of mb 4.5, depth less than 200 km and an epicentral distanc...

  7. Sigma model renormalization group flow, ``central charge'' action, and Perelman's entropy

    Science.gov (United States)

    Tseytlin, A. A.

    2007-03-01

    Zamolodchikov’s c-theorem type argument (and also string theory effective action constructions) imply that the RG flow in 2d sigma model should be a gradient one to all loop orders. However, the monotonicity of the flow of the target-space metric is not obvious since the metric on the space of metric-dilaton couplings is indefinite. To leading (one-loop) order when the RG flow is simply the Ricci flow the monotonicity was proved by Perelman [G. Perelman, math.dg/0211159.] by constructing an “entropy” functional which is essentially the metric-dilaton action extremized with respect to the dilaton with a condition that the target-space volume is fixed. We discuss how to generalize the Perelman’s construction to all loop orders (i.e. all orders in α'). The resulting entropy is equal to minus the central charge at the fixed points, in agreement with the general claim of the c-theorem.

  8. Performance evaluation of ionospheric time delay forecasting models using GPS observations at a low-latitude station

    Science.gov (United States)

    Sivavaraprasad, G.; Venkata Ratnam, D.

    2017-07-01

    Ionospheric delay is one of the major atmospheric effects on the performance of satellite-based radio navigation systems. It limits the accuracy and availability of Global Positioning System (GPS) measurements, related to critical societal and safety applications. The temporal and spatial gradients of ionospheric total electron content (TEC) are driven by several unknown priori geophysical conditions and solar-terrestrial phenomena. Thereby, the prediction of ionospheric delay is challenging especially over Indian sub-continent. Therefore, an appropriate short/long-term ionospheric delay forecasting model is necessary. Hence, the intent of this paper is to forecast ionospheric delays by considering day to day, monthly and seasonal ionospheric TEC variations. GPS-TEC data (January 2013-December 2013) is extracted from a multi frequency GPS receiver established at K L University, Vaddeswaram, Guntur station (geographic: 16.37°N, 80.37°E; geomagnetic: 7.44°N, 153.75°E), India. An evaluation, in terms of forecasting capabilities, of three ionospheric time delay models - an Auto Regressive Moving Average (ARMA) model, Auto Regressive Integrated Moving Average (ARIMA) model, and a Holt-Winter's model is presented. The performances of these models are evaluated through error measurement analysis during both geomagnetic quiet and disturbed days. It is found that, ARMA model is effectively forecasting the ionospheric delay with an accuracy of 82-94%, which is 10% more superior to ARIMA and Holt-Winter's models. Moreover, the modeled VTEC derived from International Reference Ionosphere, IRI (IRI-2012) model and new global TEC model, Neustrelitz TEC Model (NTCM-GL) have compared with forecasted VTEC values of ARMA, ARIMA and Holt-Winter's models during geomagnetic quiet days. The forecast results are indicating that ARMA model would be useful to set up an early warning system for ionospheric disturbances at low latitude regions.

  9. Collective charge excitations and the metal-insulator transition in the square lattice Hubbard-Coulomb model

    Science.gov (United States)

    Ulybyshev, Maksim; Winterowd, Christopher; Zafeiropoulos, Savvas

    2017-11-01

    In this article, we discuss the nontrivial collective charge excitations (plasmons) of the extended square lattice Hubbard model. Using a fully nonperturbative approach, we employ the hybrid Monte Carlo algorithm to simulate the system at half-filling. A modified Backus-Gilbert method is introduced to obtain the spectral functions via numerical analytic continuation. We directly compute the single-particle density of states which demonstrates the formation of Hubbard bands in the strongly correlated phase. The momentum-resolved charge susceptibility also is computed on the basis of the Euclidean charge-density-density correlator. In agreement with previous extended dynamical mean-field theory studies, we find that, at high strength of the electron-electron interaction, the plasmon dispersion develops two branches.

  10. Computer-aided model analysis for ionic strength-dependent effective charge of protein in ion-exchange chromatography

    DEFF Research Database (Denmark)

    Lim, Young-il; Jørgensen, Sten Bay; Kim, In-Ho

    2005-01-01

    differential algebraic equation (PDAE) system, a fast and accurate numerical method (i.e., conservation element/solution element (CE/SE) method), is proposed. Sensitivity and elasticity of the model parameters (e.g., steric/shape factors, adsorption heat coefficient, effective protein charge, equilibrium...... constant, mass transfer coefficient, axial dispersion coefficient and bed voidage) are analyzed for a BSA-salt system in a low protein concentration range. Within a low concentration range of bovine serum albumin (BSA) where linear adsorption isotherms are shown, the adsorption heat coefficient, shape...... salt concentrations, it is proposed that the effective protein charge could depend upon the salt concentration (or ionic strength). The reason for this dependence may be a steric hindrance of protein binding sites combined with a salt shielding effect neutralizing the surface charges of the protein. (c...

  11. Modeling of Electric Field Around 100 MVA 150/20 kV Power Transformator using Charge Simulation Method

    Directory of Open Access Journals (Sweden)

    Noviadi Arief Rachman

    2013-07-01

    Full Text Available Charge Simulation Method is one of the field theory that can be used as an approach to calculate the electromagnetic distribution on the electrical conductor. This paper discussed electric field modeling around power transformator by using Matlab to find the safety distance. The safe distance threshold of the electric field to human health refers to WHO and SNI was 5 kV/m. The specification of the power transformator was three phases, 150/20 kV, and 100 MVA. The basic concept is to change the distribution charge on the conductor or dielectric polarization charge with a set of discrete fictitious charge. The value of discrete fictitious charge was equivalent to the potential value of the conductor, and became a reference to calculate the electric field around the surface contour of the selected power transformator. The measurement distance was 5 meter on each side of the transformator surface. The results showed that the magnitude of the electric field at the front side was 5541 V/m, exceeding the safety limits.

  12. CHARGE syndrome modeling using patient-iPSCs reveals defective migration of neural crest cells harboring CHD7 mutations.

    Science.gov (United States)

    Okuno, Hironobu; Renault Mihara, Francois; Ohta, Shigeki; Fukuda, Kimiko; Kurosawa, Kenji; Akamatsu, Wado; Sanosaka, Tsukasa; Kohyama, Jun; Hayashi, Kanehiro; Nakajima, Kazunori; Takahashi, Takao; Wysocka, Joanna; Kosaki, Kenjiro; Okano, Hideyuki

    2017-11-28

    CHARGE syndrome is caused by heterozygous mutations in the chromatin remodeler, CHD7, and is characterized by a set of malformations that, on clinical grounds, were historically postulated to arise from defects in neural crest formation during embryogenesis. To better delineate neural crest defects in CHARGE syndrome, we generated induced pluripotent stem cells (iPSCs) from two patients with typical syndrome manifestations, and characterized neural crest cells differentiated in vitro from these iPSCs (iPSC-NCCs). We found that expression of genes associated with cell migration was altered in CHARGE iPSC-NCCs compared to control iPSC-NCCs. Consistently, CHARGE iPSC-NCCs showed defective delamination, migration and motility in vitro, and their transplantation in ovo revealed overall defective migratory activity in the chick embryo. These results support the historical inference that CHARGE syndrome patients exhibit defects in neural crest migration, and provide the first successful application of patient-derived iPSCs in modeling craniofacial disorders.

  13. Quasi-integrable non-linear Schrödinger models, infinite towers of exactly conserved charges and bright solitons

    Science.gov (United States)

    Blas, H.; do Bonfim, A. C. R.; Vilela, A. M.

    2017-05-01

    Deformations of the focusing non-linear Schrödinger model (NLS) are considered in the context of the quasi-integrability concept. We strengthen the results of JHEP 09 (2012) 103 for bright soliton collisions. We addressed the focusing NLS as a complement to the one in JHEP 03 (2016) 005 , in which the modified defocusing NLS models with dark solitons were shown to exhibit an infinite tower of exactly conserved charges. We show, by means of analytical and numerical methods, that for certain two-bright-soliton solutions, in which the modulus and phase of the complex modified NLS field exhibit even parities under a space-reflection symmetry, the first four and the sequence of even order charges are exactly conserved during the scattering process of the solitons. We perform extensive numerical simulations and consider the bright solitons with deformed potential V=2η /2+\\upepsilon{({|ψ |}^2)}^{2+\\upepsilon},\\upepsilon \\in \\mathbb{R},η parity we also show numerically the vanishing of the first non-trivial anomaly and the exact conservation of the relevant charge. So, the parity symmetry seems to be a sufficient but not a necessary condition for the existence of the infinite tower of conserved charges. The model supports elastic scattering of solitons for a wide range of values of the amplitudes and velocities and the set { η, ɛ}. Since the NLS equation is ubiquitous, our results may find potential applications in several areas of non-linear science.

  14. The meteorology of Gale crater as determined from rover environmental monitoring station observations and numerical modeling. Part I: Comparison of model simulations with observations

    Science.gov (United States)

    Pla-Garcia, Jorge; Rafkin, Scot C. R.; Kahre, Melinda; Gomez-Elvira, Javier; Hamilton, Victoria E.; Navarro, Sara; Torres, Josefina; Marín, Mercedes; Vasavada, Ashwin R.

    2016-12-01

    Air temperature, ground temperature, pressure, and wind speed and direction data obtained from the Rover Environmental Monitoring Station onboard the Mars Science Laboratory rover Curiosity are compared to data from the Mars Regional Atmospheric Modeling System. A full diurnal cycle at four different seasons (Ls 0, 90, 180 and 270) is investigated at the rover location within Gale crater, Mars. Model results are shown to be in good agreement with observations when considering the uncertainties in the observational data set. The good agreement provides justification for utilizing the model results to investigate the broader meteorological environment of the Gale crater region, which is described in the second, companion paper.

  15. Modeling space-charge-limited currents in organic semiconductors: Extracting trap density and mobility

    KAUST Repository

    Dacuña, Javier

    2011-11-28

    We have developed and have applied a mobility edge model that takes drift and diffusion currents to characterize the space-charge-limited current in organic semiconductors into account. The numerical solution of the drift-diffusion equation allows the utilization of asymmetric contacts to describe the built-in potential within the device. The model has been applied to extract information of the distribution of traps from experimental current-voltage measurements of a rubrene single crystal from Krellner showing excellent agreement across several orders of magnitude in the current. Although the two contacts are made of the same metal, an energy offset of 580 meV between them, ascribed to differences in the deposition techniques (lamination vs evaporation) was essential to correctly interpret the shape of the current-voltage characteristics at low voltage. A band mobility of 0.13cm 2V-1s-1 for holes is estimated, which is consistent with transport along the long axis of the orthorhombic unit cell. The total density of traps deeper than 0.1 eV was 2.2×1016cm -3. The sensitivity analysis and error estimation in the obtained parameters show that it is not possible to accurately resolve the shape of the trap distribution for energies deeper than 0.3 eV or shallower than 0.1 eV above the valence-band edge. The total number of traps deeper than 0.3 eV, however, can be estimated. Contact asymmetry and the diffusion component of the current play an important role in the description of the device at low bias and are required to obtain reliable information about the distribution of deep traps. © 2011 American Physical Society.

  16. Study of charged particle production in U-U collisions in the wounded quark model

    Science.gov (United States)

    Chaturvedi, O. S. K.; Srivastava, P. K.; Kumar, Ashwini; Singh, B. K.

    2017-10-01

    Recently, there has been a growing interest in the study of deformed uranium-uranium (U-U) collisions in its various geometrical configurations due to their usefulness in understanding the different aspects of quantum chromodynamics (QCD). In this paper we have studied the particle production in deformed U-U collisions at √{s_{NN}} = 193 GeV using the modified wounded quark model (WQM). At first, we have shown the variation of quark-nucleus inelastic scattering cross-section ( σ_{qA}^{in} with respect to centralities for various geometrical orientations of U-U collisions in WQM. After that we have calculated the pseudorapidity density ( dn_{ch}/d η within WQM using a two-component prescription. Further we have calculated the transverse energy density distribution ( dET/d η along with the ratio of transverse energy to charged hadron multiplicity ( ET/N_{ch} for U-U collisions and compared them with the corresponding experimental data. We have shown the scaling behavior of dn_{ch}/d η and dET/d η for different initial geometry of U-U collision with respect to p - p data at √{s_{NN}}= 200 GeV. Furthermore we have shown the Bjorken energy density achieved in U-U collisions for various configurations and compared them with experimental data of Au-Au at 200GeV. We observe that the present model suitably describes the experimental data for minimum bias geometrical configuration of U-U collisions. An estimate for various observables in different initial geometries of U-U collisions is also presented which will be tested in future by experimental data.

  17. Nonlinear dynamics for charges particle beams with a curved axis in the matrix - recursive model

    Energy Technology Data Exchange (ETDEWEB)

    Dymnikov, A.D. [University of St Petersburg, (Russian Federation). Institute of Computational Mathematics and Control Process

    1993-12-31

    In this paper a new matrix and recursive approach has been outlined for treating nonlinear optics of charged particle beams. This approach is a new analytical and computational tool for designers of optimal beam control systems. 9 refs.

  18. "Charge while driving" for electric vehicles: road traffic modeling and energy assessment

    National Research Council Canada - National Science Library

    Francesco Paolo DEFLORIO; Luca CASTELLO; Ivano PINNA; Paolo GUGLIELMI

    2015-01-01

      Issue Title: Special Issue on Electric Vehicles and Their Integration with Power Grid The aim of this research study is to present a method for analyzing the performance of the wireless inductive charge-while-driving (CWD...

  19. An Objective Verification of the North American Mesoscale Model for Kennedy Space Center and Cape Canaveral Air Force Station

    Science.gov (United States)

    Bauman, William H., III

    2010-01-01

    The 45th Weather Squadron (45 WS) Launch Weather Officers use the 12-km resolution North American Mesoscale (NAM) model (MesoNAM) text and graphical product forecasts extensively to support launch weather operations. However, the actual performance of the model at Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS) has not been measured objectively. In order to have tangible evidence of model performance, the 45 WS tasked the Applied Meteorology Unit to conduct a detailed statistical analysis of model output compared to observed values. The model products are provided to the 45 WS by ACTA, Inc. and include hourly forecasts from 0 to 84 hours based on model initialization times of 00, 06, 12 and 18 UTC. The objective analysis compared the MesoNAM forecast winds, temperature and dew point, as well as the changes in these parameters over time, to the observed values from the sensors in the KSC/CCAFS wind tower network. Objective statistics will give the forecasters knowledge of the model's strength and weaknesses, which will result in improved forecasts for operations.

  20. Developments of engineering model of the X-ray CCD camera of the MAXI experiment onboard the International Space Station

    CERN Document Server

    Miyata, E; Kamazuka, T; Akutsu, D; Kouno, H; Tsunemi, H; Matsuoka, M; Tomida, H; Ueno, S; Hamaguchi, K; Tanaka, I

    2002-01-01

    MAXI, Monitor of All-sky X-ray Image, is an X-ray observatory on the Japanese Experimental Module (JEM) Exposed Facility (EF) on the International Space Station (ISS). MAXI is a slit scanning camera which consists of two kinds of X-ray detectors: one is a one-dimensional position-sensitive proportional counter with a total area of approx 5000 cm sup 2 , the Gas Slit Camera (GSC), and the other is an X-ray CCD array with a total area approx 200 cm sup 2 , the Solid-state Slit Camera (SSC). The GSC subtends a field of view with an angular dimension of 1 deg. x180 deg. while the SSC subtends a field of view with an angular dimension of 1 deg. times a little less than 180 deg. . In the course of one station orbit, MAXI can scan almost the entire sky with a precision of 1 deg. and with an X-ray energy range 0.5-30 keV. We have developed an engineering model (EM) for all components of the SSC. Their performance test is underway. We have also developed several kinds of CCDs fabricated from different wafers. Since th...

  1. Hydrodynamic modeling of NOM transport in UF: effects of charge density and ionic strength on effective size and sieving.

    Science.gov (United States)

    Yuan, Yanxiao; Kilduff, James E

    2009-07-15

    The transport behavior of natural organic matter (NOM) across polyethersulfone (PES) UF membranes having a range of nominal molecularweight cutoffs (MWCOs) was investigated and described with a hydrodynamic transport model. Transport of whole NOM and NOM fractionated on an anion exchange resin (IRA 958) was measured to investigate the impact of NOM size and charge density. It was found that the dominant transport mechanism, characterized by the membrane Peclet number, depended on the membrane MWCO, and transitioned from diffusion to convection at a MWCO of about 10 kDa. Increasing ionic strength significantly decreased the effective solute radius and decreased the observed rejection of charged NOM fractions, whereas no significant change was seen for neutral fractions. Using an available theoretical model for partitioning of charged solutes, the effect of ionic strength on the electrical double layer thickness can account for the observed changes in effective solute radius. These results provide insight into the role of solute charge and electrostatic interactions in NOM transport behavior.

  2. Application of Gauss's law space-charge limited emission model in iterative particle tracking method

    Energy Technology Data Exchange (ETDEWEB)

    Altsybeyev, V.V., E-mail: v.altsybeev@spbu.ru; Ponomarev, V.A.

    2016-11-01

    The particle tracking method with a so-called gun iteration for modeling the space charge is discussed in the following paper. We suggest to apply the emission model based on the Gauss's law for the calculation of the space charge limited current density distribution using considered method. Based on the presented emission model we have developed a numerical algorithm for this calculations. This approach allows us to perform accurate and low time consumpting numerical simulations for different vacuum sources with the curved emitting surfaces and also in the presence of additional physical effects such as bipolar flows and backscattered electrons. The results of the simulations of the cylindrical diode and diode with elliptical emitter with the use of axysimmetric coordinates are presented. The high efficiency and accuracy of the suggested approach are confirmed by the obtained results and comparisons with the analytical solutions.

  3. The neutrino charge radius as a probe of physics beyond the standard model

    Energy Technology Data Exchange (ETDEWEB)

    Novales-Sanchez, H.; Toscano, J. J. [Facultad de Ciencias Fisico Matematicas, Benemerita Universidad Autonoma de Puebla, Apartado Postal 1152, Puebla, Pue (Mexico); Rosado, A.; Santiago-Olan, V. [Instituto de Fisica, Benemerita Universidad Autonoma de Puebla. Apdo. Postal J-48, C.P. 72570 Puebla, Pue (Mexico)

    2013-06-12

    In this paper, we review the search of possible physics effects beyond the standard model on the electromagnetic charge and anapole form factors, f{sub Q}(q{sup 2}) and f{sub A}(q{sup 2}), for a no massive Dirac neutrino, when these quantities are calculated in the frame of an effective electroweak Yang-Mills theory, which induces the most general SU{sub L}(2)-invariant Lorentz tensor structure of nonrenormalizable type for the WW{gamma} vertex. We found that in this frame, besides the standard model contribution, the additional contribution to f{sub Q}(q{sup 2}) and f{sub A}(q{sup 2}) (f{sub Q}{sup O{sub W}}(q{sup 2}) and f{sub A}{sup O{sub W}}(q{sup 2}), respectively) are gauge independent and finite functions of q{sup 2} after adopting a renormalization scheme. These form factors, f{sub Q}{sup O{sub W}}(q{sup 2}) and f{sub A}{sup O{sub W}}(q{sup 2}), get contribution at the one loop level only from the proper neutrino electromagnetic vertex. Besides, the relation f{sub Q}{sup eff}(q{sup 2}) = q{sup 2}f{sub A}{sup eff}(q{sup 2})(f{sub Q}{sup eff}(q{sup 2}) = f{sub Q}{sup SM}(q{sup 2})+f{sub Q}{sup O{sub W}}(q{sup 2}),f{sub A}{sup eff}(q{sup 2}) = f{sub A}{sup SM}(q{sup 2})+f{sub A}{sup O{sub W}}(q{sup 2})) is still fulfilled and hence the relation a{sub v}{sup eff} = {sup eff}/6(a{sub v}{sup eff} = a{sub v}{sup SM}+a{sub v}{sup O{sub W}},{sup eff} = {sup SM}+{sup O{sub W}}) is obtained, just as in the SM. Using the experimental constraint on the anomalous WW{gamma} vertex, a value for the additional contribution to the charge radius of Double-Vertical-Line {sup O{sub W}} Double-Vertical-Line Less-Than-Or-Equivalent-To 10{sup -34} cm{sup 2} is gotten, which is one order of magnitude lower than the SM value.

  4. Station-based deconstructed training model for teaching procedural skills to medical students: a quasi-experimental study

    Directory of Open Access Journals (Sweden)

    Mahdi Panah Khahi

    2010-09-01

    Full Text Available Seyyed M Razavi1, Mojgan Karbakhsh1, Mahdi Panah Khahi2, Soheila Dabiran1, Sara Asefi3, GhamarH Zaker Shahrak4, Ali R Bad Afrooz41Department of Community Medicine, 2Department of Anesthesiology, 3Department of General Practice, 4Clinical Skills Center, Tehran University of Medical Sciences, IranBackground: Every procedural skill consists of some microskills. One of the effective techniques for teaching a main procedural skill is to deconstruct the skill into a series of microskills and train students on each microskill separately. When we learn microskills, we will learn the main skill also. This model can be beneficial for tuition on procedural skills.Objective: In this study, we propose a stationed-based deconstructed training model for tuition of each microskill, and then we assessed the medical students’ self-perceived abilities.Methods: This quasi-experimental study was conducted in 268 medical students (536 matched pre- and post-questionnaires at the surgical clerkship stage during five consecutive years in three teaching and learning groups. In this study, we taught each skill in 10 steps (proposed model to the students. We then evaluated the students’ self-perceived abilities using a pre- and post-self-assessment technique. SPSS v13 software with one-way analysis of variance and paired t-tests were used for data collection and analysis.Results: Assessment of medical students’ perceived abilities before and after training showed a significant improvement (P < 0.001 in both cognitive and practical domains. There were also significant differences between the three teaching and learning groups (P < 0.001. There were no significant differences for the different years of training regarding the observed improvement.Conclusion: This study suggests that deconstructing the practical skills into microskills and tuition of those microskills via the separated structured educational stations is effective according to the students’ self

  5. Modeling on oxide dependent 2DEG sheet charge density and threshold voltage in AlGaN/GaN MOSHEMT

    Science.gov (United States)

    Panda, J.; Jena, K.; Swain, R.; Lenka, T. R.

    2016-04-01

    We have developed a physics based analytical model for the calculation of threshold voltage, two dimensional electron gas (2DEG) density and surface potential for AlGaN/GaN metal oxide semiconductor high electron mobility transistors (MOSHEMT). The developed model includes important parameters like polarization charge density at oxide/AlGaN and AlGaN/GaN interfaces, interfacial defect oxide charges and donor charges at the surface of the AlGaN barrier. The effects of two different gate oxides (Al2O3 and HfO2) are compared for the performance evaluation of the proposed MOSHEMT. The MOSHEMTs with Al2O3 dielectric have an advantage of significant increase in 2DEG up to 1.2 × 1013 cm-2 with an increase in oxide thickness up to 10 nm as compared to HfO2 dielectric MOSHEMT. The surface potential for HfO2 based device decreases from 2 to -1.6 eV within 10 nm of oxide thickness whereas for the Al2O3 based device a sharp transition of surface potential occurs from 2.8 to -8.3 eV. The variation in oxide thickness and gate metal work function of the proposed MOSHEMT shifts the threshold voltage from negative to positive realizing the enhanced mode operation. Further to validate the model, the device is simulated in Silvaco Technology Computer Aided Design (TCAD) showing good agreement with the proposed model results. The accuracy of the developed calculations of the proposed model can be used to develop a complete physics based 2DEG sheet charge density and threshold voltage model for GaN MOSHEMT devices for performance analysis.

  6. Charge-dependent non-bonded interaction methods for use in quantum mechanical modeling of condensed phase reactions

    Science.gov (United States)

    Kuechler, Erich R.

    Molecular modeling and computer simulation techniques can provide detailed insight into biochemical phenomena. This dissertation describes the development, implementation and parameterization of two methods for the accurate modeling of chemical reactions in aqueous environments, with a concerted scientific effort towards the inclusion of charge-dependent non-bonded non-electrostatic interactions into currently used computational frameworks. The first of these models, QXD, modifies interactions in a hybrid quantum mechanical/molecular (QM/MM) mechanical framework to overcome the current limitations of 'atom typing' QM atoms; an inaccurate and non-intuitive practice for chemically active species as these static atom types are dictated by the local bonding and electrostatic environment of the atoms they represent, which will change over the course of the simulation. The efficacy QXD model is demonstrated using a specific reaction parameterization (SRP) of the Austin Model 1 (AM1) Hamiltonian by simultaneously capturing the reaction barrier for chloride ion attack on methylchloride in solution and the solvation free energies of a series of compounds including the reagents of the reaction. The second, VRSCOSMO, is an implicit solvation model for use with the DFTB3/3OB Hamiltonian for biochemical reactions; allowing for accurate modeling of ionic compound solvation properties while overcoming the discontinuous nature of conventional PCM models when chemical reaction coordinates. The VRSCOSMO model is shown to accurately model the solvation properties of over 200 chemical compounds while also providing smooth, continuous reaction surfaces for a series of biologically motivated phosphoryl transesterification reactions. Both of these methods incorporate charge-dependent behavior into the non-bonded interactions variationally, allowing the 'size' of atoms to change in meaningful ways with respect to changes in local charge state, as to provide an accurate, predictive and

  7. Comprehensive modelling study on observed new particle formation at the SORPES station in Nanjing, China

    Directory of Open Access Journals (Sweden)

    X. Huang

    2016-03-01

    Full Text Available New particle formation (NPF has been investigated intensively during the last 2 decades because of its influence on aerosol population and the possible contribution to cloud condensation nuclei. However, intensive measurements and modelling activities on this topic in urban metropolitan areas in China with frequent high-pollution episodes are still very limited. This study provides results from a comprehensive modelling study on the occurrence of NPF events in the western part of the Yangtze River Delta (YRD region, China. The comprehensive modelling system, which combines the WRF-Chem (the Weather Research and Forecasting model coupled with Chemistry regional chemical transport model and the MALTE-BOX sectional box model (the model to predict new aerosol formation in the lower troposphere, was shown to be capable of simulating atmospheric nucleation and subsequent growth. Here we present a detailed discussion of three typical NPF days, during which the measured air masses were notably influenced by either anthropogenic activities, biogenic emissions, or mixed ocean and continental sources. Overall, simulated NPF events were generally in good agreement with the corresponding measurements, enabling us to get further insights into NPF processes in the YRD region. Based on the simulations, we conclude that biogenic organic compounds, particularly monoterpenes, play an essential role in the initial condensational growth of newly formed clusters through their low-volatility oxidation products. Although some uncertainties remain in this modelling system, this method provides a possibility to better understand particle formation and growth processes.

  8. Conjugated block copolymers as model materials to examine charge transfer in donor-acceptor systems

    Science.gov (United States)

    Gomez, Enrique; Aplan, Melissa; Lee, Youngmin

    Weak intermolecular interactions and disorder at junctions of different organic materials limit the performance and stability of organic interfaces and hence the applicability of organic semiconductors to electronic devices. The lack of control of interfacial structure has also prevented studies of how driving forces promote charge photogeneration, leading to conflicting hypotheses in the organic photovoltaic literature. Our approach has focused on utilizing block copolymer architectures -where critical interfaces are controlled and stabilized by covalent bonds- to provide the hierarchical structure needed for high-performance organic electronics from self-assembled soft materials. For example, we have demonstrated control of donor-acceptor heterojunctions through microphase-separated conjugated block copolymers to achieve 3% power conversion efficiencies in non-fullerene photovoltaics. Furthermore, incorporating the donor-acceptor interface within the molecular structure facilitates studies of charge transfer processes. Conjugated block copolymers enable studies of the driving force needed for exciton dissociation to charge transfer states, which must be large to maximize charge photogeneration but must be minimized to prevent losses in photovoltage in solar cell devices. Our work has systematically varied the chemical structure, energetics, and dielectric constant to perturb charge transfer. As a consequence, we predict a minimum dielectric constant needed to minimize the driving force and therefore simultaneously maximize photocurrent and photovoltage in organic photovoltaic devices.

  9. RENEW - MAINTENANCE ESTIMATION SIMULATION MODEL FOR SPACE STATION FREEDOM PROGRAM, VERSION 3.2

    Science.gov (United States)

    Bream, B. L.

    1994-01-01

    RENEW is a maintenance event estimation simulation program developed in support of the Space Station Freedom Program (SSFP) Work Package 4 at NASA Lewis Research Center. This simulation uses reliability and maintainability (R&M) data as well as logistics data to estimate both average and time dependent maintenance demands. RENEW uses Monte Carlo techniques to generate failure and repair times as a function of the R&M and logistics parameters. The estimates are generated for a single type of orbital replacement unit (ORU). The RENEW simulation gives closer estimates of performance than steady-state average calculations since it uses a time dependent approach and depicts more factors affecting ORU failure and repair. RENEW gives both average and time dependent demand values, and generates graphs of both failures over the mission period and yearly failure occurrences. The average demand rate for the ORU over the mission period is also calculated. While RENEW displays the results in graphs, the results are also available in data tables. The process of using RENEW starts with keyboard entry of the R&M and operational data. Once entered, the data may be saved in a data file for later retrieval, and the parameters may be viewed and changed. The simulation program runs the number of Monte Carlo simulations requested by the operator. Plots and tables of the results can be viewed on the screen or sent to a printer. The results of the simulation are saved along with the input data. Help screens are provided with each menu and data entry screen. RENEW is written in BASIC and assembly language for IBM PC series and compatible computers running MS-DOS. Microsoft's QuickBasic Professional Development System and Crescent Software's QuickPak Professional are required to compile the source code. A CGA or VGA monitor is required. A sample executable is provided on the distribution media. The standard distribution medium for this program is one 5.25 inch 360K MS-DOS format diskette

  10. The Medicina Station Status Report

    Science.gov (United States)

    Orfei, Alessandro; Orlati, Andrea; Maccaferri, Giuseppe

    2013-01-01

    General information about the Medicina Radio Astronomy Station, the 32-m antenna status, and the staff in charge of the VLBI observations is provided. In 2012, the data from geodetic VLBI observations were acquired using the Mark 5A recording system with good results. Updates of the hardware were performed and are briefly described.

  11. A Stochastic model for two-station hydraulics exhibiting transient impact

    DEFF Research Database (Denmark)

    Jacobsen, Judith L.; Madsen, Henrik; Harremoës, Poul

    1997-01-01

    dispersion in the river. This approximation is expected to be a sufficiently good approximation as a tool for the ultimate aim: the description of pollutant transport in the river. The grey box modelling involves a statistical tool for estimation of the parameters in the deterministic model. The advantage......The objective of the paper is to interpret data on water level variation in a river affected by overflow from a sewer system during rain. The simplest possible, hydraulic description is combined with stochastic methods for data analysis and model parameter estimation. This combination...

  12. Space Charge Effects and Advanced Modelling for CERN Low Energy Machines

    CERN Document Server

    AUTHOR|(CDS)2088716; Rumolo, Giovanni

    The strong space charge regime of future operation of CERN’s circular particle accelerators is investigated and mitigation strategies are developed in the framework of the present thesis. The intensity upgrade of the injector chain of Large Hadron Collider (LHC) prepares the particle accelerators to meet the requirements of the High-Luminosity LHC project. Producing the specified characteristics of the future LHC beams imperatively relies on injecting brighter bunches into the Proton Synchrotron Booster (PSB), the downstream Proton Synchrotron (PS) and eventually the Super Proton Synchrotron (SPS). The increased brightness, i.e. bunch intensity per transverse emittance, entails stronger beam self-fields which can lead to harmful interaction with betatron resonances. Possible beam emittance growth and losses as a consequence thereof threaten to degrade the beam brightness. These space charge effects are partly mitigated by the upgrade of the PSB and PS injection energies. Nevertheless, the space charge tune ...

  13. Comparing the standardized live trauma patient and the mechanical simulator models in the ATLS initial assessment station.

    Science.gov (United States)

    Ali, Jameel; Dunn, Julie; Eason, Martin; Drumm, Jacob

    2010-07-01

    Mechanical simulators may be an acceptable substitute for the live patient model in trauma skills teaching and assessment. We compare these models in the initial assessment station of the Advanced Trauma Life Support (ATLS) course. After a pilot project utilizing both models in a provider ATLS course it appeared that the mechanical model would be satisfactory for ATLS teaching and assessment. Instructors (n = 32) and ATLS Students (n = 64) were randomly selected from our database and completed a questionnaire evaluating the patient model and the simulator after viewing a video in which the simulator replaced the patient model. The evaluators indicated whether the patient and simulator models were satisfactory and then compared them by indicating whether there was any difference between the models, indicating which was more challenging, interesting, dynamic, enjoyable, realistic, and better overall. Comments were also written in the evaluation form. All 32 instructors and 64 students indicated that both the patient and simulator models were satisfactory for teaching and testing ATLS resuscitation skills. At least 62 of the 64 students rated the simulator higher in all categories. Two students rated the patient model as more realistic and two noted no difference in terms of being more interesting. All 32 instructors indicated that the simulator was more challenging, interesting, dynamic, and better overall. Two of the 32 instructors indicated that the patient model was more enjoyable and two indicated that there was no difference as far as the models being realistic. Comments included inability to hear breath sounds that were changing in the patient model as opposed to the simulator model, and the simulator was more interesting and dynamic because the hemodynamic and physiologic parameters could be witnessed without being prompted by the instructor. One main concern expressed by the participants was the more costly simulator, and two instructors indicated that the

  14. Computer modeling of beam space charge effects in cyclotron injector into JINR phasotron

    CERN Document Server

    Kalinichenko, V V

    2002-01-01

    Charge particle beam dynamics including space charge by direct Coulomb particle-to-particle method was simulated. For this purpose in MATLAB a new code KASKADS was developed. Numerical simulations of the particle motion confirm that it is possible to achieve separated orbits in a 5 MeV, 30 mA separated sector cyclotron (accelerating voltage varies depending on radius from 150 kV in the centre to 240 kV in the extraction region). The aperture of the accelerator must be greater than 3 cm.

  15. Electro-osmosis in kaolinite with pH-dependent surface charge modelling by homogenization

    Directory of Open Access Journals (Sweden)

    Sidarta A. Lima

    2010-03-01

    Full Text Available A new three-scale model to describe the coupling between pH-dependent flows and transient ion transport, including adsorption phenomena in kaolinite clays, is proposed. The kaolinite is characterized by three separate nano/micro and macroscopic length scales. The pore (micro-scale is characterized by micro-pores saturated by an aqueous solution containing four monovalent ions and charged solid particles surrounded by thin electrical double layers. The movement of the ions is governed by the Nernst-Planck equations, and the influence of the double layers upon the flow is dictated by the Helmholtz-Smoluchowski slip boundary condition on the tangential velocity. In addition, an adsorption interface condition for the Na+ transportis postulated to capture its retention in the electrical double layer. Thetwo-scalenano/micro model including salt adsorption and slip boundary condition is homogenized to the Darcy scale and leads to the derivation of macroscopic governing equations. One of the notable features of the three-scale model is there construction of the constitutive law of effective partition coefficient that governs the sodium adsorption in the double layer. To illustrate the feasibility of the three-scale model in simulating soil decontamination by electrokinetics, the macroscopic model is discretized by the finite volume method and the desalination of a kaolinite sample by electrokinetics is simulated.Neste artigo propomos um modelo em três escalas para descrever o acoplamento entre o fluxo eletroosmótico e o transporte de íons incluindo fenômenos de adsorção em uma caulinita. A argila é caracterizada por três escalas nano/micro e macroscópica. A escala microscópica é constituída por micro-poros saturados por uma solução aquosa contendo quatro íons monovalentes e partículas sólidas carregadas eletricamente circundadas por uma dupla camada elétrica fina. O movimento dos íons é governado pelas equações de Nernst-Planck e a

  16. Development of Electric Vehicle Charging Corridor for South Carolina

    Directory of Open Access Journals (Sweden)

    Shengyin Li, Ph.D. candidate

    2015-01-01

    Full Text Available We apply a flow-based location model, called Multipath Refueling Location Model (MPRLM, to develop an electric vehicle (EV public charging infrastructure network for enabling long-haul inter-city EV trips. The model considers multiple deviation paths between every origin-destination (O-D pairs and relaxes the commonly adopted assumption that travelers only take a shortest path between O-D pairs. This model is a mixed-integer linear program, which is intrinsically difficult to solve. With greedy-adding based heuristics, the MPRLM is applied to optimally deploy EV fast charging stations along major highway corridors in South Carolina. Compared to engineering methods, the optimization model reduces the capital cost of establishing a fast charging network by two thirds. We also explore the interplay between the spatial distributions of cities, vehicle range, and routing deviation tolerance as well as their impacts on the locational strategies.

  17. Observation Station

    Science.gov (United States)

    Rutherford, Heather

    2011-01-01

    This article describes how a teacher integrates science observations into the writing center. At the observation station, students explore new items with a science theme and use their notes and questions for class writings every day. Students are exposed to a variety of different topics and motivated to write in different styles all while…

  18. Competition between antiferromagnetic and charge-density-wave order in the half-filled Hubbard-Holstein model.

    Science.gov (United States)

    Nowadnick, E A; Johnston, S; Moritz, B; Scalettar, R T; Devereaux, T P

    2012-12-14

    We present a determinant quantum Monte Carlo study of the competition between instantaneous on-site Coulomb repulsion and retarded phonon-mediated attraction between electrons, as described by the two-dimensional Hubbard-Holstein model. At half filling, we find a strong competition between antiferromagnetism (AFM) and charge-density-wave (CDW) order. We demonstrate that a simple picture of AFM-CDW competition that incorporates the phonon-mediated attraction into an effective-U Hubbard model requires significant refinement. Specifically, retardation effects slow the onset of charge order so that CDW order remains absent even when the effective U is negative. This delay opens a window where neither AFM nor CDW order is well established and where there are signatures of a possible metallic phase.

  19. Model-assisted development of microfabricated 3D Ni(OH)2 electrodes with rapid charging capabilities

    Science.gov (United States)

    Huang, Chenpeng; Armutlulu, Andac; Allen, Mark G.; Allen, Sue Ann Bidstrup

    2017-08-01

    Three-dimensional (3D) nickel hydroxide electrodes based on well-ordered and laminated structures are prepared via an electrochemical route combined with microfabrication technologies. The electrodes exhibit enhanced rate capabilities owing to their large surface area and reduced diffusion and conduction path lengths for the charge transfer. Highly laminated electrodes enable areal capacities as high as 2.43 mAh cm-2. When charged at fast rates of 150C, the electrodes are able to deliver more than 50% of their initial capacity. The electrochemical performance of the fabricated electrodes is predicted with close approximation by means of a mathematical model developed by employing fundamental mass transport and reaction kinetics principles. This model is then used to optimize the characteristic dimensions of the electrodes and make projections of performance for various energy and power needs.

  20. Non-standard charged Higgs decay at the LHC in Next-to-Minimal Supersymmetric Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    Bandyopadhyay, Priyotosh [Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento and INFN-Lecce,Via Arnesano, 73100 Lecce (Italy); Huitu, Katri [Department of Physics, and Helsinki Institute of Physics,P.O.B 64 (Gustaf Hällströmin katu 2), FI-00014 University of Helsinki (Finland); Niyogi, Saurabh [The Institute of Mathematical Sciences,CIT Campus, Chennai (India)

    2016-07-04

    We consider next-to-minimal supersymmetric standard model (NMSSM) which has a gauge singlet superfield. In the scale invariant superpotential we do not have the mass terms and the whole Lagrangian has an additional Z{sub 3} symmetry. This model can have light scalar and/or pseudoscalar allowed by the recent data from LHC and the old data from LEP. We investigate the situation where a relatively light charged Higgs can decay to such a singlet-like pseudoscalar and a W{sup ±} boson giving rise to a final state containing τ and/or b-jets and lepton(s). Such decays evade the recent bounds on charged Higgs from the LHC, and according to our PYTHIA-FastJet based simulation can be probed with 10 fb{sup −1} at the LHC center of mass energy of 13 and 14 TeV.

  1. A three-dimensional numerical modelling of the PHOENIX-SPES charge breeder based on the Langevin formalism

    Science.gov (United States)

    Galatà, A.; Mascali, D.; Neri, L.; Torrisi, G.; Celona, L.

    2016-02-01

    A Charge Breeder (CB) is a crucial device of an ISOL facility, allowing post-acceleration of radioactive ions: it accepts an incoming 1+ beam, then multiplying its charge with a highly charged q+ beam as an output. The overall performances of the facility (intensity and attainable final energy) critically depend on the charge breeder optimization. Experimental results collected along the years confirm that the breeding process is still not fully understood and room for improvements still exists: a new numerical approach has been therefore developed and applied to the description of a 85Rb1+ beam capture by the plasma of the 14.5 GHz PHOENIX ECR-based CB, installed at the Laboratoire de Physique Subatomique et de Cosmologie (LPSC), and adopted for the Selective Production of Exotic Species project under construction at Laboratori Nazionali di Legnaro. The results of the numerical simulations, obtained implementing a plasma-target model of increasing accuracy and different values for the plasma potential, will be described along the paper: results very well agree with the theoretical predictions and with the experimental results obtained on the LPSC test bench.

  2. A three-dimensional numerical modelling of the PHOENIX-SPES charge breeder based on the Langevin formalism

    Energy Technology Data Exchange (ETDEWEB)

    Galatà, A., E-mail: alessio.galata@lnl.infn.it [INFN–Laboratori Nazionali di Legnaro, Viale dell’Università 2, 35020 Legnaro, Padova (Italy); Mascali, D.; Neri, L.; Torrisi, G.; Celona, L. [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy)

    2016-02-15

    A Charge Breeder (CB) is a crucial device of an ISOL facility, allowing post-acceleration of radioactive ions: it accepts an incoming 1+ beam, then multiplying its charge with a highly charged q+ beam as an output. The overall performances of the facility (intensity and attainable final energy) critically depend on the charge breeder optimization. Experimental results collected along the years confirm that the breeding process is still not fully understood and room for improvements still exists: a new numerical approach has been therefore developed and applied to the description of a {sup 85}Rb{sup 1+} beam capture by the plasma of the 14.5 GHz PHOENIX ECR-based CB, installed at the Laboratoire de Physique Subatomique et de Cosmologie (LPSC), and adopted for the Selective Production of Exotic Species project under construction at Laboratori Nazionali di Legnaro. The results of the numerical simulations, obtained implementing a plasma-target model of increasing accuracy and different values for the plasma potential, will be described along the paper: results very well agree with the theoretical predictions and with the experimental results obtained on the LPSC test bench.

  3. Search for a light-charged Higgs in a two-Higgs-doublet type II seesaw model at the LHC

    Directory of Open Access Journals (Sweden)

    Chuan-Hung Chen

    2017-04-01

    Full Text Available A charged Higgs in the type II two-Higgs-doublet model (THDM has been bounded to be above a few hundred GeV by the radiative B decays. A Higgs triplet extension of the THDM not only provides an origin of neutrino masses and a completely new doubly-charged Higgs decay pattern, but it also achieves a light-charged Higgs with a mass of O(100 GeV through the new scalar couplings in the scalar potential. It was found that these light-charged Higgs decays depend on its mass mH±, tan⁡β, and mixing effect sin⁡θ±: at tan⁡β=1, if mH±>mW+mZ, b¯bW±, W±Z, and τν are the main decay modes; however, if mH±mH±+mb, we found that the ATLAS and CMS recent upper bounds on the product of BR(t→H+bBR(H+→τ+ν can be directly applied and will give a strict constraint on the correlation of mH± and sin⁡θ±. If the upper bound of BR(t→H+bBR(H+→τ+ν is satisfied (escaped for mt>(mW+mZ.

  4. Developing Fully Coupled Dynamical Reactor Core Isolation System Models in RELAP-7 for Extended Station Black-Out Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Haihua Zhao; Ling Zou; Hongbin Zhang; David Andrs; Richard Martineau

    2014-04-01

    The reactor core isolation cooling (RCIC) system in a boiling water reactor (BWR) provides makeup water to the reactor vessel for core cooling when the main steam lines are isolated and the normal supply of water to the reactor vessel is lost. It was one of the very few safety systems still available during the Fukushima Daiichi accidents after the tsunamis hit the plants and the system successfully delayed the core meltdown for a few days for unit 2 & 3. Therefore, detailed models for RCIC system components are indispensable to understand extended station black-out accidents (SBO) for BWRs. As part of the effort to develop the new generation reactor system safety analysis code RELAP-7, major components to simulate the RCIC system have been developed. This paper describes the models for those components such as turbine, pump, and wet well. Selected individual component test simulations and a simplified SBO simulation up to but before core damage is presented. The successful implementation of the simplified RCIC and wet well models paves the way to further improve the models for safety analysis by including more detailed physical processes in the near future.

  5. Terahertz-pulse driven modulation of electronic spectra: Modeling electron-phonon coupling in charge-transfer crystals

    Science.gov (United States)

    Di Maiolo, Francesco; Masino, Matteo; Painelli, Anna

    2017-08-01

    We calculate the optical spectra of a charge-transfer crystal modulated by a terahertz pulse, accounting for electron-vibration coupling. The model Hamiltonian is parametrized against first principle calculations and adiabatic results are validated against a fully non-adiabatic calculation where relaxation phenomena are introduced via the coupling of the quantum system to a dissipative bath of classic anharmonic oscillators. The experiment is well reproduced by the proposed model with no need to introduce any ad hoc assumption on the temporal dependence of model parameters, but just accounting for the quadratic dependence of the Hubbard U on non-totally symmetric molecular coordinates.

  6. A quark model calculation for the short-range contribution in the pion double charge exchange reaction

    Energy Technology Data Exchange (ETDEWEB)

    Zou Bingsong; Jiang Huanqing (Institute of Theoretical Physics and Institute of High Energy Physcis, Academia Sinica, Beijing (CN))

    1989-10-01

    A quark model calculation for the short-range contribution in the pion double charge exchange (DCX) reaction is presented. In the framework of this new model the angular distributions of {sup 18}O({pi}{sup +},{pi}{sup {minus}}){sup 18}Ne(g.s.) at low energies are calculated and compared with the experimental data. It is found that this model can explain the anomalous'' increasing behavior for the DCX reaction around 50 MeV quite well.

  7. Ames Culture Chamber System: Enabling Model Organism Research Aboard the international Space Station

    Science.gov (United States)

    Steele, Marianne

    2014-01-01

    Understanding the genetic, physiological, and behavioral effects of spaceflight on living organisms and elucidating the molecular mechanisms that underlie these effects are high priorities for NASA. Certain organisms, known as model organisms, are widely studied to help researchers better understand how all biological systems function. Small model organisms such as nem-atodes, slime mold, bacteria, green algae, yeast, and moss can be used to study the effects of micro- and reduced gravity at both the cellular and systems level over multiple generations. Many model organisms have sequenced genomes and published data sets on their transcriptomes and proteomes that enable scientific investigations of the molecular mechanisms underlying the adaptations of these organisms to space flight.

  8. EVALAUTION MODEL OF THE FUNCTIONAL CONDITION OF THE RADAR STATIONS ATC, CONSIDERING EXTERNAL CHANGES

    Directory of Open Access Journals (Sweden)

    V. E. Emelyanov

    2014-01-01

    Full Text Available The article deals with specification evaluation model of radars reliability which operate in different working conditions, resulting from exposure to various external disturbances. The assessment possibility of the operating expenses level according to the value which depends on the emission efficiency of the signal which is determined by external influences is also shown.

  9. Residential exposure to RF-EMF from mobile phone base stations: Model predictions versus personal and home measurements.

    Science.gov (United States)

    Martens, Astrid L; Slottje, Pauline; Meima, Marie Y; Beekhuizen, Johan; Timmermans, Danielle; Kromhout, Hans; Smid, Tjabe; Vermeulen, Roel C H

    2016-04-15

    Geospatial models have been demonstrated to reliably and efficiently estimate RF-EMF exposure from mobile phone base stations (downlink) at stationary locations with the implicit assumption that this reflects personal exposure. In this study we evaluated whether RF-EMF model predictions at the home address are a good proxy of personal 48h exposure. We furthermore studied potential modification of this association by degree of urbanisation. We first used an initial NISMap estimation (at an assumed height of 4.5m) for 9563 randomly selected addresses in order to oversample addresses with higher exposure levels and achieve exposure contrast. We included 47 individuals across the range of potential RF-EMF exposure and used NISMap to re-assess downlink exposure at the home address (at bedroom height). We computed several indicators to determine the accuracy of the NISMap model predictions. We compared residential RF-EMF model predictions with personal 48h, at home, and night-time (0:00-8:00AM) ExpoM3 measurements, and with EME-SPY 140 spot measurements in the bedroom. We obtained information about urbanisation degree and compared the accuracy of model predictions in high and low urbanised areas. We found a moderate Spearman correlation between model predictions and personal 48h (rSp=0.47), at home (rSp=0.49), at night (rSp=0.51) and spot measurements (rSp=0.54). We found no clear differences between high and low urbanised areas (48h: high rSp=0.38, low rSp=0.55, bedroom spot measurements: high rSp=0.55, low rSp=0.50). We achieved a meaningful ranking of personal downlink exposure irrespective of degree of urbanisation, indicating that these models can provide a good proxy of personal exposure in areas with varying build-up. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. GROMOS polarizable charge-on-spring models for liquid urea: COS/U and COS/U2

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Zhixiong; Bachmann, Stephan J.; Gunsteren, Wilfred F. van, E-mail: wfvgn@igc.phys.chem.ethz.ch [Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH, 8093 Zürich (Switzerland)

    2015-03-07

    Two one-site polarizable urea models, COS/U and COS/U2, based on the charge-on-spring model are proposed. The models are parametrized against thermodynamic properties of urea-water mixtures in combination with the polarizable COS/G2 and COS/D2 models for liquid water, respectively, and have the same functional form of the inter-atomic interaction function and are based on the same parameter calibration procedure and type of experimental data as used to develop the GROMOS biomolecular force field. Thermodynamic, dielectric, and dynamic properties of urea-water mixtures simulated using the polarizable models are closer to experimental data than using the non-polarizable models. The COS/U and COS/U2 models may be used in biomolecular simulations of protein denaturation.

  11. Modeling the electric potential across neuronal membranes: the effect of fixed charges on spinal ganglion neurons and neuroblastoma cells.

    Directory of Open Access Journals (Sweden)

    Thiago M Pinto

    Full Text Available We present a model for the electric potential profile across the membranes of neuronal cells. We considered the resting and action potential states, and analyzed the influence of fixed charges of the membrane on its electric potential, based on experimental values of membrane properties of the spinal ganglion neuron and the neuroblastoma cell. The spinal ganglion neuron represents a healthy neuron, and the neuroblastoma cell, which is tumorous, represents a pathological neuron. We numerically solved the non-linear Poisson-Boltzmann equation for the regions of the membrane model we have adopted, by considering the densities of charges dissolved in an electrolytic solution and fixed on both glycocalyx and cytoplasmic proteins. Our model predicts that there is a difference in the behavior of the electric potential profiles of the two types of cells, in response to changes in charge concentrations in the membrane. Our results also describe an insensitivity of the neuroblastoma cell membrane, as observed in some biological experiments. This electrical property may be responsible for the low pharmacological response of the neuroblastoma to certain chemotherapeutic treatments.

  12. Extended Kalman filter method for state of charge estimation of vanadium redox flow battery using thermal-dependent electrical model

    Science.gov (United States)

    Xiong, Binyu; Zhao, Jiyun; Wei, Zhongbao; Skyllas-Kazacos, Maria

    2014-09-01

    State of charge (SOC) estimation is a key issue for battery management since an accurate estimation method can ensure safe operation and prevent the over-charge/discharge of a battery. Traditionally, open circuit voltage (OCV) method is utilized to estimate the stack SOC and one open flow cell is needed in each battery stack [1,2]. In this paper, an alternative method, extended Kalman filter (EKF) method, is proposed for SOC estimation for VRBs. By measuring the stack terminal voltages and applied currents, SOC can be predicted with a state estimator instead of an additional open circuit flow cell. To implement EKF estimator, an electrical model is required for battery analysis. A thermal-dependent electrical circuit model is proposed to describe the charge/discharge characteristics of the VRB. Two scenarios are tested for the robustness of the EKF. For the lab testing scenarios, the filtered stack voltage tracks the experimental data despite the model errors. For the online operation, the simulated temperature rise is observed and the maximum SOC error is within 5.5%. It is concluded that EKF method is capable of accurately predicting SOC using stack terminal voltages and applied currents in the absence of an open flow cell for OCV measurement.

  13. The charge form factor of pseudoscalar mesons in a relativistic constituent quark model

    Energy Technology Data Exchange (ETDEWEB)

    Cardarelli, F.; Pace, E. [Univ. of Rome, Roma (Italy); Grach, I.L. [Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation)] [and others

    1994-04-01

    The charge form factor of pseudoscalar mesons has been investigated in the light-cone formalism, up to Q{sup 2} relevant to CEBAF energies. The consequences of adopting the meson wave functions generated through the Godfrey-Isgur q{bar q} potential, which reproduces the mass spectra, are discussed.

  14. Study of smell and reproductive organs in a mouse model for CHARGE syndrome

    NARCIS (Netherlands)

    Bergman, Jorieke E. H.; Bosman, Erika A.; van Ravenswaaij-Arts, Conny M. A.; Steel, Karen P.

    CHARGE syndrome is a multiple congenital anomaly syndrome characterised by Coloboma, Heart defects, Atresia of choanae, Retardation of growth and/or development, Genital hypoplasia, and Ear anomalies often associated with deafness. It is caused by heterozygous mutations in the CHD7 gene and shows a

  15. Search for charged Higgs bosons at LEP in general two Higgs doublet models

    NARCIS (Netherlands)

    Abdallah, J.; Blom, M.R.; Drees, J.; Siebel, M.; van Dam, P.A.; Zupan, M.

    2004-01-01

    A search for pair-produced charged Higgs bosons was performed in the data collected by the DELPHI detector at LEP II at centre-of-mass energies from 189 GeV to 209 GeV. Five different final states, τ

  16. Modeling, simulation and command of purification stations using activated muds considering nitrification and denitrification processes

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, M.; Gendreau, P.; Babary, J.P.

    1994-04-01

    The results presented in this study are a first approach in the area of modeling, simulation and command of a water purification pilot process. The works have been established before the pilot starts, therefore only from wanted values for the pilot characteristics, and not from experimental measures. Simplified models have been built by taking support on already undertaken works (Henze et al., 1986; Jeppsson, 1993). The simulation has allowed to get results that can be acceptable from a dynamic point of view. The numerical values could be specified from measures made with the pilot. The closed loop command supplies results that are acceptable from the point of view of the process biological behaviour. (N.C.). 19 refs., 20 figs.

  17. The meteorology of Gale Crater as determined from Rover Environmental Monitoring Station observations and numerical modeling. Part II: Interpretation

    Science.gov (United States)

    Rafkin, Scot C. R.; Pla-Garcia, Jorge; Kahre, Melinda; Gomez-Elvira, Javier; Hamilton, Victoria E.; Marín, Mercedes; Navarro, Sara; Torres, Josefina; Vasavada, Ashwin

    2016-12-01

    Numerical modeling results from the Mars Regional Atmospheric Modeling System are used to interpret the landed meteorological data from the Rover Environmental Monitoring Station onboard the Mars Science Laboratory rover Curiosity. In order to characterize seasonal changes throughout the Martian year, simulations are conducted at Ls 0, 90, 180 and 270. Two additional simulations at Ls 225 and 315 are explored to better understand the unique meteorological setting centered on Ls 270. The synergistic combination of model and observations reveals a complex meteorological environment within the crater. Seasonal planetary circulations, the thermal tide, slope flows along the topographic dichotomy, mesoscale waves, slope flows along the crater slopes and Mt. Sharp, and turbulent motions all interact in nonlinear ways to produce the observed weather. Ls 270 is shown to be an anomalous season when air within and outside the crater is well mixed by strong, flushing northerly flow and large amplitude, breaking mountain waves. At other seasons, the air in the crater is more isolated from the surrounding environment. The potential impact of the partially isolated crater air mass on the dust, water, noncondensable and methane cycles is also considered. In contrast to previous studies, the large amplitude diurnal pressure signal is attributed primarily to necessary hydrostatic adjustments associated with topography of different elevations, with contributions of less than 25% to the diurnal amplitude from the crater circulation itself. The crater circulation is shown to induce a suppressed boundary layer.

  18. Model depiction of the atmospheric flows of radioactive cesium emitted from the Fukushima Daiichi Nuclear Power Station accident

    Science.gov (United States)

    Nakajima, Teruyuki; Misawa, Shota; Morino, Yu; Tsuruta, Haruo; Goto, Daisuke; Uchida, Junya; Takemura, Toshihiko; Ohara, Toshimasa; Oura, Yasuji; Ebihara, Mitsuru; Satoh, Masaki

    2017-12-01

    In this study, a new method is proposed for the depiction of the atmospheric transportation of the 137Cs emitted from the Fukushima Daiichi Nuclear Power Station accident. This method employs a combination of the results of two aerosol model ensembles and the hourly observed atmospheric 137Cs concentration at surface level during 14-23 March 2011 at 90 sites in the suspended particulate matter monitoring network. The new method elucidates accurate transport routes and the distribution of the surface-level atmospheric 137Cs relevant to eight plume events that were previously identified. The model ensemble simulates the main features of the observed distribution of surface-level atmospheric 137Cs. However, significant differences were found in some cases, and this suggests the need to improve the modeling of the emission scenario, plume height, wet deposition process, and plume propagation in the Abukuma Mountain region. The contributions of these error sources differ in the early and dissipating phases of each event, depending on the meteorological conditions.

  19. Design of Smart Charging Infrastructure Hardware and Firmware Design of the Various Current Multiplexing Charging System

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Ching-Yen; Chu, Peter; Gadh, Rajit

    2013-10-07

    Currently, when Electric Vehicles (EVs) are charging, they only have the option to charge at a selected current or not charge. When during the day there is a power shortage, the charging infrastructure should have the options to either shut off the power to the charging stations or to lower the power to the EVs in order to satisfy the needs of the grid. There is a need for technology that controls the current being disbursed to these electric vehicles. This paper proposes a design for a smart charging infrastructure capable of providing power to several EVs from one circuit by multiplexing power and providing charge control. The smart charging infrastructure includes the server and the smart charging station. With this smart charging infrastructure, the shortage of energy in a local grid could be solved by our EV management system

  20. Increasing the Usage of Personal Protective Equipments in Constructing Subway Stations: An Application of Social Marketing Model

    Directory of Open Access Journals (Sweden)

    M Shams

    2013-10-01

    Full Text Available Abstract Background & aim: Although the relationship between the use of personal protective equipment and the reduction of workplace injuries is well-known the use of these devices during operation by the staff is not so desirable. This study was based on a model of social marketing interventions to increase the use of safety devices and personal protection on the subway-station staff. Methods: The present quasi-experimental study was based on the results of a formative research consisted of a qualitative (exploring employees’ views through focus group discussions and a quantitative study (measuring attitudes and behaviors by questionnaire and checklist. Based on the formative research findings, a free package includes a helmet with a label containing the message, an anti-cut safety gloves, a dust mask, and an educational pamphlet were delivered to intervention group. After four weeks, the check list of observational behaviors in two constructing stations was completed and the results were compared with before intervention. The data were analyzed by paired t-test, t-test and logistic regression. Results: Three common behaviors were observed among staff not using caps, masks and gloves. The odds ratio for helmet and mask usage in the intervention group was more than other groups. After the intervention, the use of safety helmets and masks significantly increased (p < 0.05. The odds ratio for the use of helmets and masks after intervention in the intervention group was significantly higher than other groups (p < 0.05. Conclusion: The experimental basis of the safety devices and personal protection needs and demands of the audience, material and immaterial costs of the equipment, supplies, and promoting their use in the right place, can encourage the staff to continuously use the safety devices at workplace. Key Words: Workplace, Injuries, Personal Protective Equipment, Social Marketing

  1. Evaluation of Maximum Radionuclide Groundwater Concentrations for Basement Fill Model. Zion Station Restoration Project

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Terry [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-02-22

    The objectives of this report are; To present a simplified conceptual model for release from the buildings with residual subsurface structures that can be used to provide an upper bound on contaminant concentrations in the fill material; Provide maximum water concentrations and the corresponding amount of mass sorbed to the solid fill material that could occur in each building for use in dose assessment calculations; Estimate the maximum concentration in a well located outside of the fill material; and Perform a sensitivity analysis of key parameters.

  2. A mathematical model for the municipal solid waste location-routing problem with intermediate transfer stations

    Directory of Open Access Journals (Sweden)

    Hossein Asefi

    2015-09-01

    Full Text Available Municipal solid waste management is one of the challenging issues in mega cities due to various interrelated factors such as operational costs and environmental concerns. Cost as one of the most significant constraints of municipal solid waste management can be effectively economized by efficient planning approaches. Considering diverse waste types in an integrated municipal solid waste system, a mathematical model of the location-routing problem is formulated and solved in this study in order to minimize the total cost of transportation and facility establishment.

  3. Evaluation of reduced point charge models of proteins through Molecular Dynamics simulations: application to the Vps27 UIM-1-Ubiquitin complex.

    Science.gov (United States)

    Leherte, Laurence; Vercauteren, Daniel P

    2014-02-01

    Reduced point charge models of amino acids are designed, (i) from local extrema positions in charge density distribution functions built from the Poisson equation applied to smoothed molecular electrostatic potential (MEP) functions, and (ii) from local maxima positions in promolecular electron density distribution functions. Corresponding charge values are fitted versus all-atom Amber99 MEPs. To easily generate reduced point charge models for protein structures, libraries of amino acid templates are built. The program GROMACS is used to generate stable Molecular Dynamics trajectories of an Ubiquitin-ligand complex (PDB: 1Q0W), under various implementation schemes, solvation, and temperature conditions. Point charges that are not located on atoms are considered as virtual sites with a nul mass and radius. The results illustrate how the intra- and inter-molecular H-bond interactions are affected by the degree of reduction of the point charge models and give directions for their implementation; a special attention to the atoms selected to locate the virtual sites and to the Coulomb-14 interactions is needed. Results obtained at various temperatures suggest that the use of reduced point charge models allows to probe local potential hyper-surface minima that are similar to the all-atom ones, but are characterized by lower energy barriers. It enables to generate various conformations of the protein complex more rapidly than the all-atom point charge representation. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Analysis of charging and sudden-discharging characteristics of no-insulation REBCO coil using an electromagnetic coupling model

    Directory of Open Access Journals (Sweden)

    Donghui Liu

    2017-11-01

    Full Text Available No-insulation (NI high-temperature superconducting (HTS REBCO coil has been a promising candidate for manufacturing high-field superconducting magnets with high thermal stability and self-protecting features. When NI coil is operated at the external field, it is necessary to analyze charging and sudden-discharging characteristics of NI coil by considering the effect of magnetic field. In addition, the self-field effect has an obvious influence on the critical current for large-scale coil. Thus, an electromagnetic coupling model in which an equivalent circuit axisymmetric model considers the effect of magnetic field is proposed. The results show that when the radial current exists, the coil voltage and central field will tend to be stable faster. In a high field, the decrease of the critical current leads to the increase of radial current and this effect is more obvious for a larger field. And the charging time with the increase of the external field reduces significantly, while the sudden-discharging time is almost unchanged. For NI coils composed of many double-pancake coils, the charging time and sudden-discharging time proportionally increase with the increase of the number of double-pancake coil and turn number of single-pancake coil.

  5. Modeling Payload Stowage Impacts on Fire Risks On-Board the International Space Station

    Science.gov (United States)

    Anton, Kellie e.; Brown, Patrick F.

    2010-01-01

    The purpose of this presentation is to determine the risks of fire on-board the ISS due to non-standard stowage. ISS stowage is constantly being reexamined for optimality. Non-standard stowage involves stowing items outside of rack drawers, and fire risk is a key concern and is heavily mitigated. A Methodology is needed to account for fire risk due to non-standard stowage to capture the risk. The contents include: 1) Fire Risk Background; 2) General Assumptions; 3) Modeling Techniques; 4) Event Sequence Diagram (ESD); 5) Qualitative Fire Analysis; 6) Sample Qualitative Results for Fire Risk; 7) Qualitative Stowage Analysis; 8) Sample Qualitative Results for Non-Standard Stowage; and 9) Quantitative Analysis Basic Event Data.

  6. Models of and approaches to the station management of six African community radio broadcasters

    Directory of Open Access Journals (Sweden)

    Linje Manyozo

    2012-03-01

    Full Text Available This article is a political economy critique that contributes to current scholarship on community radio and development by examining the question of the management of six networks from Mali, Mozambique and Uganda. This discussion argues that understanding the models and functions of management committees will go a long way towards contributing to conversations on how community radios could achieve social, institutional, financial and ideological sustainability. The article also examines how management committees approach their work in the age of new Information Communication Technologies (especially mobile phones, computers and the Internet, and whether there is a gender digital divide within such committees. At the centre of thecurrent discussion, therefore, is an attempt to understand the flow and contestation of power within community radio management committees.

  7. MICRODOSIMETRIC MODELING OF THE RELATIVE LUMINESCENCE EFFICIENCY OF LiF:Mg,Ti (MTS) DETECTORS EXPOSED TO CHARGED PARTICLES.

    Science.gov (United States)

    Parisi, Alessio; Van Hoey, Olivier; Vanhavere, Filip

    2017-09-29

    A microdosimetric model has been developed to predict the relative efficiency of luminescent detectors for measuring different radiation qualities. The model has been tested for LiF:Mg,Ti (MTS) detectors exposed to charged particles from 1H to 132Xe in the energy range 3-1000 MeV/u. The obtained results have been compared with experimental data present in literature showing very good agreement in case of calculations performed in a site size of 40 nm. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Coexistence of superconductivity and charge-density waves in a two-dimensional Holstein model at half-filling

    Energy Technology Data Exchange (ETDEWEB)

    Sykora, Steffen; Huebsch, Arnd; Becker, Klaus W. [Institut fuer Theoretische Physik, Technische Universitaet Dresden, 01062 Dresden (Germany)

    2008-07-01

    The competition of charge-density waves (CDW) and superconductivity (SC) is studied in a two-dimensional half-filled Holstein model by use of the projector-based renormalization method (PRM). As is well known, in one dimension the coupling of electrons to phonons leads to a transition from a metallic to a Peierls distorted insulated state when the coupling exceeds a critical value. On the other hand, in two dimensions the electron-phonon interaction may also be responsible for the formation of Cooper pairs. In this paper, the competing influence of superconductivity and charge order will be discussed for two dimensions. The PRM not only allows to study SC and CDW correlation functions but gives direct access to the order parameters.

  9. Understanding the interplay between charge, spin and phonons in the spectral properties of the 1D Hubbard-Holstein model

    Science.gov (United States)

    Soltanieh-Ha, Mohammad; Nocera, Alberto; Feiguin, Adrian

    2014-03-01

    We present an analytical construction to calculate the spectral functions of the Hubbard-Holstein model in the limit of strong electron-phonon coupling, and in the limit of U --> ∞ . We argue that in this limit, the phonons only couple to the charge, and not the spin. The resulting spectral function can be understood as a convolution of three contributions, originating from the charge, the spin, and the phonons, in a similar fashion as the large U limit of the Hubbard chain. We support the analytical results with extensive Density Matrix Renormalization Group simulations. We recognize and interpret the signatures of the three contributions in the final spectrum and we discuss their experimental implications.

  10. Modeling of intense charged particle bunch dynamics in external magnetic fields

    Science.gov (United States)

    Barminova, H. Y.; Saratovskyh, M. S.

    2015-09-01

    Program module CAMFT is developed to simulate the intense charged particle bunch dynamics in external magnetic fields. The program is based on the accurate solution of the motion equation for each particle of the intense bunch. The program is written on C++ language and uses standart OpenMP (version 2.0) for parallelization, so one can simulate the behavior of the bunch with intensity about 109-1010 particles. Visual C++ and library Qt 4.8.3 of qtcreator are used for the result visualization. Dynamics of the bunch with arbitrary phase distributions in magnetic fields of arbitrary geometry may be studied by means of the program. The actual CAMFT version is checked while simulating the accelerating structure with racetrack geometry. Modified CAMFT version is checked for ITEP Heavy-Ion Prototype charge-state separator.

  11. Macroscopic models for charge exchange reactions in N not = Z nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Stringari, S.; Lipparini, E.

    1987-10-19

    Vlasov equations in the isospin channels are derived in the framework of the time dependent Hartree-Fock theory. The local equilibrium (hydrodynamic) approximation is then considered and applied to study isovector giant resonances excited in charge exchange reactions and ..mu../sup -/ inclusive capture in N not = Z nuclei. The theoretical predictions well account for the observed energy splitting between different isospin fragments and for the quenching of the ..delta..T/sub Z/ = +1 strength.

  12. Modelling of Coke Layer Collapse during Ore Charging in Ironmaking Blast Furnace by DEM

    OpenAIRE

    Narita Yoichi; Mio Hiroshi; Orimoto Takashi; Nomura Seiji

    2017-01-01

    A technical issue in an ironmaking blast furnace operation is to realize the optimum layer thickness and the radial distribution of burden (ore and coke) to enhance its efficiency and productivity. When ore particles are charged onto the already-embedded coke layer, the coke layer-collapse phenomenon occurs. The coke layer-collapse phenomenon has a significant effect on the distribution of ore and coke layer thickness in the radial direction. In this paper, the mechanical properties of coke p...

  13. Modelling the influence of urbanization on the 20th century temperature record of weather station De Bilt (The Netherlands)

    NARCIS (Netherlands)

    Koopmans, S.; Theeuwes, N.E.; Steeneveld, G.J.; Holtslag, A.A.M.

    2015-01-01

    Many cities have expanded during the 20th century, and consequently some weather stations are currently located closer to cities than before. Due to the urban heat island (UHI) effect, those weather stations may show a positive bias in their 2-m temperature record. In this study, we estimate the

  14. Dispersion modeling and health risk assessment of VOCs emissions from municipal solid waste transfer station in Tehran, Iran.

    Science.gov (United States)

    Sarkhosh, Maryam; Shamsipour, AliAkbar; Yaghmaeian, Kamyar; Nabizadeh, Ramin; Naddafi, Kazem; Mohseni, Seyed Mohsen

    2017-01-01

    The waste transfer stations (WTSs) is one of the most important factors affecting on environment and human health. This research is aimed to evaluate health risk of VOCs among WTS personnel and provide a model for dispersion of VOCs. The Air Pollution Model (TAPM) is able to simulate WTS emissions dispersion over each town. GC-MS was used to analysis collected gas samples to detect and estimate carcinogenic and non-carcinogenic VOCs health risks. The total lifetime cancer risk values for the all personnel (3.30E-05), was more than acceptable limit (1.00E-06). Furthermore, hazard ratio (HR) of 1,2,3-trimethylbenzene, 1,3-dichloropropane, toluene, m,p-xylene and ethylbenzene were 3.7, 1.9 E-01, 4.4 E-03, 5.5 E-02 and 1.5 E-03, respectively, and total HR of the mentioned compounds were more than accepted limit (HR < 1.00). IOA is 0.85 and RMSE is 2.16 and TAPM has a good performance. The VOCs level is considerable in 1600 m far from the WTS particularly in summer that require more attention. The exposure to VOCs was at a high level in WTS, and some controlling strategy should be used for decreasing the pollution and protecting the citizens and personnel against non-cancerous and cancerous risks.

  15. Modeling of a Flooding Induced Station Blackout for a Pressurized Water Reactor Using the RISMC Toolkit

    Energy Technology Data Exchange (ETDEWEB)

    Mandelli, Diego; Prescott, Steven R; Smith, Curtis L; Alfonsi, Andrea; Rabiti, Cristian; Cogliati, Joshua J; Kinoshita, Robert A

    2011-07-01

    In the Risk Informed Safety Margin Characterization (RISMC) approach we want to understand not just the frequency of an event like core damage, but how close we are (or are not) to key safety-related events and how might we increase our safety margins. The RISMC Pathway uses the probabilistic margin approach to quantify impacts to reliability and safety by coupling both probabilistic (via stochastic simulation) and mechanistic (via physics models) approaches. This coupling takes place through the interchange of physical parameters and operational or accident scenarios. In this paper we apply the RISMC approach to evaluate the impact of a power uprate on a pressurized water reactor (PWR) for a tsunami-induced flooding test case. This analysis is performed using the RISMC toolkit: RELAP-7 and RAVEN codes. RELAP-7 is the new generation of system analysis codes that is responsible for simulating the thermal-hydraulic dynamics of PWR and boiling water reactor systems. RAVEN has two capabilities: to act as a controller of the RELAP-7 simulation (e.g., system activation) and to perform statistical analyses (e.g., run multiple RELAP-7 simulations where sequencing/timing of events have been changed according to a set of stochastic distributions). By using the RISMC toolkit, we can evaluate how power uprate affects the system recovery measures needed to avoid core damage after the PWR lost all available AC power by a tsunami induced flooding. The simulation of the actual flooding is performed by using a smooth particle hydrodynamics code: NEUTRINO.

  16. THE OPTIMIZATION APPROACH OF POSTAL TRANSPORTATION NETWORK BASED ON UNCAPACITATED FIXED CHARGE LOCATION MODEL IN CONDITIONS OF SLOVAK REPUBLIC

    Directory of Open Access Journals (Sweden)

    Radovan MADLEŇÁK

    2015-12-01

    Full Text Available The article deals with the possibilities of optimizing the postal transportation network with respect to planned road infrastructure. The research adopted in this article uses allocation models within graph theory to obtain results for addressed optimization problem. The article presents and compares two types of these models – p-median and uncapacitated fixed charge facility location model. The latter is subsequently applied on the postal network to determine the optimal location of postal facilities while minimizing costs. Moreover, the article describes the possibilities of identifying and calculating input variables of the used model, creating the underlying network, as well as possible further improvements of obtained solution. The results can serve as a basis for modification of the used model for the simulation of networks in the postal sector.

  17. Charge based, continuous compact model for the channel current in organic thin-film transistors for all regions of operation

    Science.gov (United States)

    Hain, Franziska; Graef, Michael; Iñíguez, Benjamín; Kloes, Alexander

    2017-07-01

    In general most modeling approaches for organic field-effect transistors (OFETs) are based on the typical MOSFET equations. The threshold voltage is usually a fitting parameter without relation to physical parameters hence the impact of their variability on the threshold voltage is not clear. The presented modeling approach is charge based with a continuous equation for the channel current in organic field-effect transistors from below to above threshold. The model provides a physics based parameter set related to trap states, and a compatible parameter set from a circuit designer's perspective. An expression for the threshold voltage is derived depending on the density of trap states. The model considers a power-law mobility model, parasitic contact resistances and channel length modulation effects and is verified with measurements on OFETs fabricated with small molecules.

  18. Analytical model of threshold voltage degradation due to localized charges in gate material engineered Schottky barrier cylindrical GAA MOSFETs

    Science.gov (United States)

    Kumar, Manoj; Haldar, Subhasis; Gupta, Mridula; Gupta, R. S.

    2016-10-01

    The threshold voltage degradation due to the hot carrier induced localized charges (LC) is a major reliability concern for nanoscale Schottky barrier (SB) cylindrical gate all around (GAA) metal-oxide-semiconductor field-effect transistors (MOSFETs). The degradation physics of gate material engineered (GME)-SB-GAA MOSFETs due to LC is still unexplored. An explicit threshold voltage degradation model for GME-SB-GAA-MOSFETs with the incorporation of localized charges (N it) is developed. To accurately model the threshold voltage the minimum channel carrier density has been taken into account. The model renders how +/- LC affects the device subthreshold performance. One-dimensional (1D) Poisson’s and 2D Laplace equations have been solved for two different regions (fresh and damaged) with two different gate metal work-functions. LCs are considered at the drain side with low gate metal work-function as N it is more vulnerable towards the drain. For the reduction of carrier mobility degradation, a lightly doped channel has been considered. The proposed model also includes the effect of barrier height lowering at the metal-semiconductor interface. The developed model results have been verified using numerical simulation data obtained by the ATLAS-3D device simulator and excellent agreement is observed between analytical and simulation results.

  19. Mise au point d' un modele cartographique pour la description des stations forestieres en Ardenne belge

    Directory of Open Access Journals (Sweden)

    Lejeune P.

    2002-01-01

    Full Text Available Development of a cartographic mdel for the forest site types delineation in the Belgian Ardenne. The paper presents an original method dealing with the forest site types delineation. The suggested method consists in integrating a typological key in a GIS aiming at producing a thematic map that describes forest site types. Data used are the soil map of Belgium (digitized at the scale 1:20,000 and a digital elevation model built from a topographic map (scale 1:10,000. The typological key is mainly based on the methodology used by Thill et al. (1988 in the site types system for central Ardenne, the potential vegetation map of Sougnez and Dethioux (1975 and the ecoregion map of Delvaux and Galoux (1962. In that respect, site types are closely linked to the soil map and the phytosociological classification. So, they can be connected to the afforestation guide and different phytosociological and autecological studies concerning forest species. It is then possible to map the potential habitats or the site potentialities related to tree species. The key is valid for the Ardenne ecoregion located in Southern Belgium (elevation higher than 300 m. It has to be validated through an intensive use in the field, taking into account its imprecision linked to the types of collected data, chieffly those being digitized. The integration of such a tool in a SIG can be considered as an original way in terms of integrated forest management or forest sites description in the context of the project ""Natura 2000"" launched by the European Union. The study has been carried out within the framework of an experimental integrated management project concerning the Saint-Hubert forest (17,000 ha.

  20. New comprehensive standard seismic noise models and 3D seismic noise variation for Morocco territory, North Africa, obtained using seismic broadband stations

    Science.gov (United States)

    El Fellah, Younes; El-Aal, Abd El-Aziz Khairy Abd; Harnafi, Mimoun; Villaseñor, Antonio

    2017-05-01

    In the current work, we constructed new comprehensive standard seismic noise models and 3D temporal-spatial seismic noise level cubes for Morocco in north-west Africa to be used for seismological and engineering purposes. Indeed, the original global standard seismic noise models published by Peterson (1993) and their following updates by Astiz and Creager (1995), Ekström (2001) and Berger et al. (2003) had no contributing seismic stations deployed in North Africa. Consequently, this preliminary study was conducted to shed light on seismic noise levels specific to north-west Africa. For this purpose, 23 broadband seismic stations recently installed in different structural domains throughout Morocco are used to study the nature and characteristics of seismic noise and to create seismic noise models for Morocco. Continuous data recorded during 2009, 2010 and 2011 were processed and analysed to construct these new noise models and 3D noise levels from all stations. We compared the Peterson new high-noise model (NHNM) and low-noise model (NLNM) with the Moroccan high-noise model (MHNM) and low-noise model (MLNM). These new noise models are comparable to the United States Geological Survey (USGS) models in the short period band; however, in the period range 1.2 s to 1000 s for MLNM and 10 s to 1000 s for MHNM display significant variations. This variation is attributed to differences in the nature of seismic noise sources that dominate Morocco in these period bands. The results of this study have a new perception about permanent seismic noise models for this spectacular region and can be considered a significant contribution because it supplements the Peterson models and can also be used to site future permanent seismic stations in Morocco.