WorldWideScience

Sample records for vawt modeling strategy

  1. Simulating Dynamic Stall in a 2D VAWT: Modeling strategy, verification and validation with Particle Image Velocimetry data

    International Nuclear Information System (INIS)

    Ferreira, C J Simao; Bijl, H; Bussel, G van; Kuik, G van

    2007-01-01

    The implementation of wind energy conversion systems in the built environment renewed the interest and the research on Vertical Axis Wind Turbines (VAWT), which in this application present several advantages over Horizontal Axis Wind Turbines (HAWT). The VAWT has an inherent unsteady aerodynamic behavior due to the variation of angle of attack with the angle of rotation, perceived velocity and consequentially Reynolds number. The phenomenon of dynamic stall is then an intrinsic effect of the operation of a Vertical Axis Wind Turbine at low tip speed ratios, having a significant impact in both loads and power. The complexity of the unsteady aerodynamics of the VAWT makes it extremely attractive to be analyzed using Computational Fluid Dynamics (CFD) models, where an approximation of the continuity and momentum equations of the Navier-Stokes equations set is solved. The complexity of the problem and the need for new design approaches for VAWT for the built environment has driven the authors of this work to focus the research of CFD modeling of VAWT on: .comparing the results between commonly used turbulence models: URANS (Spalart-Allmaras and k-ε) and large eddy models (Large Eddy Simulation and Detached Eddy Simulation) .verifying the sensitivity of the model to its grid refinement (space and time), .evaluating the suitability of using Particle Image Velocimetry (PIV) experimental data for model validation. The 2D model created represents the middle section of a single bladed VAWT with infinite aspect ratio. The model simulates the experimental work of flow field measurement using Particle Image Velocimetry by Simao Ferreira et al for a single bladed VAWT. The results show the suitability of the PIV data for the validation of the model, the need for accurate simulation of the large eddies and the sensitivity of the model to grid refinement

  2. Simulating Dynamic Stall in a 2D VAWT: Modeling strategy, verification and validation with Particle Image Velocimetry data

    NARCIS (Netherlands)

    Ferreira, C.J.S.; Bijl, H.; Bussel, van G.J.W.; Kuik, van G.A.M.

    2007-01-01

    The implementation of wind energy conversion systems in the built environment renewed the interest and the research on Vertical Axis Wind Turbines (VAWT), which in this application present several advantages over Horizontal Axis Wind Turbines (HAWT). The VAWT has an inherent unsteady aerodynamic

  3. Analysis of VAWT aerodynamics and design using the Actuator Cylinder flow model

    DEFF Research Database (Denmark)

    Aagaard Madsen, Helge; Schmidt Paulsen, Uwe; Vita, Luca

    2012-01-01

    The actuator cylinder flow model is defined as the ideal VAWT rotor. Radial directed volume forces are applied on the circular path of the VAWT rotor airfoil and constitute an energy conversion in the flow. The power coefficient for the ideal as well as the real energy conversion is defined...

  4. Analysis of VAWT aerodynamics and design using the Actuator Cylinder flow model

    DEFF Research Database (Denmark)

    Aagaard Madsen, Helge; Schmidt Paulsen, Uwe; Vita, Luca

    2014-01-01

    The actuator cylinder (AC) flow model is defined as the ideal VAWT rotor. Radial directed volume forces are applied on the circular path of the VAWT rotor airfoil and constitute an energy conversion in the flow. The power coefficient for the ideal as well as the real energy conversion is defined....... obtainable power coefficient for a fixed pitch VAWT is constrained by the fundamental cyclic variation of inflow angle and relative velocity leading to a loading that deviates considerably from the uniform loading.......The actuator cylinder (AC) flow model is defined as the ideal VAWT rotor. Radial directed volume forces are applied on the circular path of the VAWT rotor airfoil and constitute an energy conversion in the flow. The power coefficient for the ideal as well as the real energy conversion is defined....... The describing equations for the two-dimensional AC model are presented and a solution method splitting the final solution in a linear and non-linear part is briefly described. A family of loadforms approaching the uniform loading is used to study the ideal energy conversion indicating that the maximum power...

  5. Analysis of VAWT aerodynamics and design using the Actuator Cylinder flow model

    International Nuclear Information System (INIS)

    Madsen, H Aa; Paulsen, U S; Vitae, L

    2014-01-01

    The actuator cylinder (AC) flow model is defined as the ideal VAWT rotor. Radial directed volume forces are applied on the circular path of the VAWT rotor airfoil and constitute an energy conversion in the flow. The power coefficient for the ideal as well as the real energy conversion is defined. The describing equations for the two-dimensional AC model are presented and a solution method splitting the final solution in a linear and non-linear part is briefly described. A family of loadforms approaching the uniform loading is used to study the ideal energy conversion indicating that the maximum power coefficient for the ideal energy conversion of a VAWT could exceed the Betz limit. The real energy conversion of the 5MW DeepWind rotor is simulated with the AC flow model in combination with the blade element analysis. Aerodynamic design aspects are discussed on this basis revealing that the maximum obtainable power coefficient for a fixed pitch VAWT is constrained by the fundamental cyclic variation of inflow angle and relative velocity leading to a loading that deviates considerably from the uniform loading

  6. A retrospective of VAWT technology.

    Energy Technology Data Exchange (ETDEWEB)

    Ashwill, Thomas D.; Sutherland, Herbert J. (HJS Consulting, Albuquerque, NM); Berg, Dale E.

    2012-01-01

    The study of Vertical-Axis Wind Turbine (VAWT) technology at Sandia National Laboratories started in the 1970's and concluded in the 1990's. These studies concentrated on the Darrieus configurations because of their high inherent efficiency, but other configurations (e.g., the Savonius turbine) were also examined. The Sandia VAWT program culminated with the design of the 34-m 'Test Bed' Darrieus VAWT. This turbine was designed and built to test various VAWT design concepts and to provide the necessary databases to validate analytical design codes and algorithms. Using the Test Bed as their starting point, FloWind Corp. developed a commercial VAWT product line with composite blades and an extended height-to-diameter ratio. The purpose of this paper is to discuss the design process and results of the Sandia 34-m VAWT Test Bed program and the FloWind prototype development program with an eye toward future offshore designs. This paper is our retrospective of the design, analysis, testing and commercial process. Special emphasis is given to those lessons learned that will aid in the development of an off-shore VAWT.

  7. On the way to reliable aeroelastic load simulation on VAWT's

    DEFF Research Database (Denmark)

    Larsen, Torben J.; Aagaard Madsen, Helge

    2013-01-01

    In this paper a method for an implementation of a 2D actuator cylinder flow model of an Vertical Axis Wind Turbine (VAWT) is presented. The model is implemented in a full aeroelastic code including consideration of structural dynamics, dynamic inflow, tower shadow and dynamic stall, which is needed...... for a full load analysis relating to eg. certification of a VAWT turbine. Further on, principal load cases according to the IEC61400-1 are simulated for a fictitious 5MW VAWT turbine in it’s simplest 2 bladed Darrieus configuration. The IEC61400-1 load cases, originally developed for Horizontal Axis Wind...... Turbines (HAWT’s), are discussed regarding the application to VAWT’s. Further on a small section regarding aerodynamic flow in curved motion is included....

  8. Vertical axis wind turbine turbulent response model. Part 2: Response of Sandia National laboratories' 34-meter VAWT with aeroelastic effects

    Science.gov (United States)

    1990-01-01

    The dynamic response of Sandia National Laboratories' 34-m Darrieus rotor wind turbine at Bushland, Texas, is presented. The formulation used a double-multiple streamtube aerodynamic model with a turbulent airflow and included the effects of linear aeroelastic forces. The structural analysis used established procedures with the program MSC/NASTRAN. The effects of aeroelastic forces on the damping of natural modes agree well with previous results at operating rotor speeds, but show some discrepancies at very high rotor speeds. A number of alternative expressions for the spectrum of turbulent wind were investigated. The model loading represented by each does not differ significantly; a more significant difference is caused by imposing a full lateral coherence of the turbulent flow. Spectra of the predicted stresses at various locations show that without aeroelastic forces, very severe resonance is likely to occur at certain natural frequencies. Inclusion of aeroelastic effects greatly attenuates this stochastic response, especially in modes involving in-plane blade bending.

  9. Analysis of Different Blade Architectures on small VAWT Performance

    Science.gov (United States)

    Battisti, L.; Brighenti, A.; Benini, E.; Raciti Castelli, M.

    2016-09-01

    The present paper aims at describing and comparing different small Vertical Axis Wind Turbine (VAWT) architectures, in terms of performance and loads. These characteristics can be highlighted by resorting to the Blade Element-Momentum (BE-M) model, commonly adopted for rotor pre-design and controller assessment. After validating the model with experimental data, the paper focuses on the analysis of VAWT loads depending on some relevant rotor features: blade number (2 and 3), airfoil camber line (comparing symmetrical and asymmetrical profiles) and blade inclination (straight versus helical blade). The effect of such characteristics on both power and thrusts (in the streamwise direction and in the crosswise one) as a function of both the blades azimuthal position and their Tip Speed Ratio (TSR) are presented and widely discussed.

  10. Reliability of numerical wind tunnels for VAWT simulation

    International Nuclear Information System (INIS)

    Castelli, M. Raciti; Masi, M.; Battisti, L.; Benini, E.; Brighenti, A.; Dossena, V.; Persico, G.

    2016-01-01

    Computational Fluid Dynamics (CFD) based on the Unsteady Reynolds Averaged Navier Stokes (URANS) equations have long been widely used to study vertical axis wind turbines (VAWTs). Following a comprehensive experimental survey on the wakes downwind of a troposkien-shaped rotor, a campaign of bi-dimensional simulations is presented here, with the aim of assessing its reliability in reproducing the main features of the flow, also identifying areas needing additional research. Starting from both a well consolidated turbulence model (k-ω SST) and an unstructured grid typology, the main simulation settings are here manipulated in a convenient form to tackle rotating grids reproducing a VAWT operating in an open jet wind tunnel. The dependence of the numerical predictions from the selected grid spacing is investigated, thus establishing the less refined grid size that is still capable of capturing some relevant flow features such as integral quantities (rotor torque) and local ones (wake velocities). (paper)

  11. Reliability of numerical wind tunnels for VAWT simulation

    Science.gov (United States)

    Raciti Castelli, M.; Masi, M.; Battisti, L.; Benini, E.; Brighenti, A.; Dossena, V.; Persico, G.

    2016-09-01

    Computational Fluid Dynamics (CFD) based on the Unsteady Reynolds Averaged Navier Stokes (URANS) equations have long been widely used to study vertical axis wind turbines (VAWTs). Following a comprehensive experimental survey on the wakes downwind of a troposkien-shaped rotor, a campaign of bi-dimensional simulations is presented here, with the aim of assessing its reliability in reproducing the main features of the flow, also identifying areas needing additional research. Starting from both a well consolidated turbulence model (k-ω SST) and an unstructured grid typology, the main simulation settings are here manipulated in a convenient form to tackle rotating grids reproducing a VAWT operating in an open jet wind tunnel. The dependence of the numerical predictions from the selected grid spacing is investigated, thus establishing the less refined grid size that is still capable of capturing some relevant flow features such as integral quantities (rotor torque) and local ones (wake velocities).

  12. An aerodynamic study on flexed blades for VAWT applications

    Science.gov (United States)

    Micallef, Daniel; Farrugia, Russell; Sant, Tonio; Mollicone, Pierluigi

    2014-12-01

    There is renewed interest in aerodynamics research of VAWT rotors. Lift type, Darrieus designs sometimes use flexed blades to have an 'egg-beater shape' with an optimum Troposkien geometry to minimize the structural stress on the blades. While straight bladed VAWTs have been investigated in depth through both measurements and numerical modelling, the aerodynamics of flexed blades has not been researched with the same level of detail. Two major effects may have a substantial impact on blade performance. First, flexing at the equator causes relatively strong trailing vorticity to be released. Secondly, the blade performance at each station along the blade is influenced by self-induced velocities due to bound vorticity. The latter is not present in a straight bladed configuration. The aim of this research is to investigate these effects in relation to an innovative 4kW wind turbine concept being developed in collaboration with industry known as a self-adjusting VAWT (or SATVAWT). The approach used in this study is based on experimental and numerical work. A lifting line free-wake vortex model was developed. Wind tunnel power and hot-wire velocity measurements were performed on a scaled down, 60cm high, three bladed model in a closed wind tunnel. Results show a substantial axial wake induction at the equator resulting in a lower power generation at this position. This induction increases with increasing degree of flexure. The self-induced velocities caused by blade bound vorticity at a particular station was found to be relatively small.

  13. Variable Pitch Approach for Performance Improving of Straight-Bladed VAWT at Rated Tip Speed Ratio

    Directory of Open Access Journals (Sweden)

    Zhenzhou Zhao

    2018-06-01

    Full Text Available This paper presents a new variable pitch (VP approach to increase the peak power coefficient of the straight-bladed vertical-axis wind turbine (VAWT, by widening the azimuthal angle band of the blade with the highest aerodynamic torque, instead of increasing the highest torque. The new VP-approach provides a curve of pitch angle designed for the blade operating at the rated tip speed ratio (TSR corresponding to the peak power coefficient of the fixed pitch (FP-VAWT. The effects of the new approach are exploited by using the double multiple stream tubes (DMST model and Prandtl’s mathematics to evaluate the blade tip loss. The research describes the effects from six aspects, including the lift, drag, angle of attack (AoA, resultant velocity, torque, and power output, through a comparison between VP-VAWTs and FP-VAWTs working at four TSRs: 4, 4.5, 5, and 5.5. Compared with the FP-blade, the VP-blade has a wider azimuthal zone with the maximum AoA, lift, drag, and torque in the upwind half-cycle, and yields the two new larger maximum values in the downwind half-cycle. The power distribution in the swept area of the turbine changes from an arched shape of the FP-VAWT into the rectangular shape of the VP-VAWT. The new VP-approach markedly widens the highest-performance zone of the blade in a revolution, and ultimately achieves an 18.9% growth of the peak power coefficient of the VAWT at the optimum TSR. Besides achieving this growth, the new pitching method will enhance the performance at TSRs that are higher than current optimal values, and an increase of torque is also generated.

  14. Overview of Vertical Axis Wind Turbine (VAWT)

    Science.gov (United States)

    Sullivan, W. N.

    1979-01-01

    A survey is presented of the practices which were applied for designing VAWT blades. An attempt is made to discuss strengths and weaknesses of the existing procedures. Discussion is provided on planned or suggested future work in developing improved design tools.

  15. An aerodynamic study on flexed blades for VAWT applications

    International Nuclear Information System (INIS)

    Micallef, Daniel; Farrugia, Russell; Sant, Tonio; Mollicone, Pierluigi

    2014-01-01

    There is renewed interest in aerodynamics research of VAWT rotors. Lift type, Darrieus designs sometimes use flexed blades to have an 'egg-beater shape' with an optimum Troposkien geometry to minimize the structural stress on the blades. While straight bladed VAWTs have been investigated in depth through both measurements and numerical modelling, the aerodynamics of flexed blades has not been researched with the same level of detail. Two major effects may have a substantial impact on blade performance. First, flexing at the equator causes relatively strong trailing vorticity to be released. Secondly, the blade performance at each station along the blade is influenced by self-induced velocities due to bound vorticity. The latter is not present in a straight bladed configuration. The aim of this research is to investigate these effects in relation to an innovative 4kW wind turbine concept being developed in collaboration with industry known as a self-adjusting VAWT (or SATVAWT). The approach used in this study is based on experimental and numerical work. A lifting line free-wake vortex model was developed. Wind tunnel power and hot-wire velocity measurements were performed on a scaled down, 60cm high, three bladed model in a closed wind tunnel. Results show a substantial axial wake induction at the equator resulting in a lower power generation at this position. This induction increases with increasing degree of flexure. The self-induced velocities caused by blade bound vorticity at a particular station was found to be relatively small

  16. Benchmarking (Code2Code) of the 1Hs 3-Bladed Onshore VAWT

    DEFF Research Database (Denmark)

    Galinos, Christos; Schmidt Paulsen, Uwe

    This study is part of the Inflow project. In this report the Nenuphar’s onshore 3-bladed Vertical Axis Wind Turbine (VAWT) prototype (1HS) is modelled in HAWC2 aeroelastic code. In the first part the model properties are summarized. Then the analysis is focused on the rotor performance and various...

  17. Operational modal analysis on a VAWT in a large wind tunnel using stereo vision technique

    International Nuclear Information System (INIS)

    Najafi, Nadia; Paulsen, Uwe Schmidt

    2017-01-01

    This paper is about development and use of a research based stereo vision system for vibration and operational modal analysis on a parked, 1-kW, 3-bladed vertical axis wind turbine (VAWT), tested in a wind tunnel at high wind. Vibrations were explored experimentally by tracking small deflections of the markers on the structure with two cameras, and also numerically, to study structural vibrations in an overall objective to investigate challenges and to prove the capability of using stereo vision. Two high speed cameras provided displacement measurements at no wind speed interference. The displacement time series were obtained using a robust image processing algorithm and analyzed with data-driven stochastic subspace identification (DD-SSI) method. In addition of exploring structural behaviour, the VAWT testing gave us the possibility to study aerodynamic effects at Reynolds number of approximately 2 × 10"5. VAWT dynamics were simulated using HAWC2. The stereo vision results and HAWC2 simulations agree within 4% except for mode 3 and 4. The high aerodynamic damping of one of the blades, in flatwise motion, would explain the gap between those two modes from simulation and stereo vision. A set of conventional sensors, such as accelerometers and strain gauges, are also measuring rotor vibration during the experiment. The spectral analysis of the output signals of the conventional sensors agrees the stereo vision results within 4% except for mode 4 which is due to the inaccuracy of spectral analysis in picking very closely spaced modes. Finally, the uncertainty of the 3D displacement measurement was evaluated by applying a generalized method based on the law of error propagation, for a linear camera model of the stereo vision system. - Highlights: • The stereo vision technique is used to track deflections on a VAWT in the wind tunnel. • OMA is applied on displacement time series to study the dynamic behaviour of the VAWT. • Stereo vision results enabled us to

  18. Numerical simulation of VAWT on the effects of rotation cylinder

    Science.gov (United States)

    Xing, Shuda; Cao, Yang; Ren, Fuji

    2017-06-01

    Based on Finite Element Analysis Method, studying on Vertical Axis Wind Turbine (VAWT) which is added rotating cylinder in front of its air foils, especially focusing on the analysis of NACA6 series air foils about variation of lift to drag ratio. Choosing the most suitable blades with rotary cylinder added on leading edge. Analysis indicates that the front rotating cylinders on the VAWT is benefit to lift rise and drag fall. The most suitable air foil whose design lift coefficient is 0.8, the blades relative thickness is 20%, and the optimistic tip speed ratio is about 7.

  19. Performance prediction of asymmetrical bladed H-Darrieus VAWT rotors in low wind speed condition using CFD

    Science.gov (United States)

    Mazarbhuiya, Hussain Mahamed Sahed Mostafa; Biswas, Agnimitra; Sharma, Kaushal Kumar

    2018-04-01

    Wind energy is an essential and carbon free form of renewable energy resources. Energy can be easily extracted from wind with the use of Horizontal axis and Vertical axis wind turbine(VAWT). The performance of turbine depends on airfoil shape. The present work emphasizes the aerodynamics of different asymmetrical airfoils used in VAWT rotors. This investigation is conducted for the selection of efficient asymmetrical bladed H-Darrieus VAWT rotor. Five numbers of thick and cambered asymmetrical airfoil is considered for this investigation. A free stream velocity of 6.0 m/s is considered to simulate 2D CFD analysis using k-ɛ turbulence model. The power coefficient (Cp) of all H-Darrieus VAWT rotor increase with increase in TSR value to a certain limit and after it starts decrease with further increase of TSR. In the present investigation the Cp and TSR of NACA 63415 (RT-30%) are found to be higher among all considered asymmetrical airfoils. Moreover, Ct values of NACA 63415 (RT-30%) are also high corresponding to all TSR values. This is due to the long duration of attachment of flow with blade surroundings. Hence, NACA 63415 (RT- 30%) airfoil may be considered as an efficient airfoil among S818, GOE 561, GU25-5(11)8, and KENNEDY AND MARSDEN (kenmar) asymmetrical airfoils.

  20. Application of computational fluid dynamics (CFD) simulation in a vertical axis wind turbine (VAWT) system

    Science.gov (United States)

    Kao, Jui-Hsiang; Tseng, Po-Yuan

    2018-01-01

    The objective of this paper is to describe the application of CFD (Computational fluid dynamics) technology in the matching of turbine blades and generator to increase the efficiency of a vertical axis wind turbine (VAWT). A VAWT is treated as the study case here. The SST (Shear-Stress Transport) k-ω turbulence model with SIMPLE algorithm method in transient state is applied to solve the T (torque)-N (r/min) curves of the turbine blades at different wind speed. The T-N curves of the generator at different CV (constant voltage) model are measured. Thus, the T-N curves of the turbine blades at different wind speed can be matched by the T-N curves of the generator at different CV model to find the optimal CV model. As the optimal CV mode is selected, the characteristics of the operating points, such as tip speed ratio, revolutions per minute, blade torque, and efficiency, can be identified. The results show that, if the two systems are matched well, the final output power at a high wind speed of 9-10 m/s will be increased by 15%.

  1. A 34-meter VAWT (Vertical Axis Wind Turbine) point design

    Science.gov (United States)

    Ashwill, T. D.; Berg, D. E.; Dodd, H. M.; Rumsey, M. A.; Sutherland, H. J.; Veers, P. S.

    The Wind Energy Division at Sandia National Laboratories recently completed a point design based on the 34-m Vertical Axis Wind Turbine (VAWT) Test Bed. The 34-m Test Bed research machine incorporates several innovations that improve Darrieus technology, including increased energy production, over previous machines. The point design differs minimally from the Test Bed; but by removing research-related items, its estimated cost is substantially reduced. The point design is a first step towards a Test-Bed-based commercial machine that would be competitive with conventional sources of power in the mid-1990s.

  2. Desirable airfoil features for smaller-capacity straight-bladed VAWT

    Energy Technology Data Exchange (ETDEWEB)

    Islam, Mazharul; Ting, D.S.-K.; Fartaj, Amir

    2007-05-15

    In the small scale wind turbine market, the simple straight-bladed Darrieus type vertical axis wind turbine (SB-VAWT) is very attractive for its simple blade design. A detailed aerodynamic performance analysis was conducted on a smaller capacity fixed-pitch SB-VAWT. Brief analyses of the main aerodynamic challenges of this type of wind turbine were first discussed and subsequently the authors conducted further literature survey and computational analysis to shortlist aerodynamic characteristics of a desirable airfoil for a self-starting and better performing SB-VAWT. The required geometric features of the desirable airfoil to achieve the short listed characteristics were also discussed. It has been found out that conventionally used NACA symmetric airfoils are not suitable for smaller capacity SB-VAWT. Rather, it is advantageous to utilize a high-lift and low-drag asymmetric thick airfoil suitable for low speed operation typically encountered by SB-VAWT. (author)

  3. Comparison of aerodynamic models for Vertical Axis Wind Turbines

    DEFF Research Database (Denmark)

    Ferreira, C. Simão; Aagaard Madsen, Helge; Barone, M.

    2014-01-01

    Multi-megawatt Vertical Axis Wind Turbines (VAWTs) are experiencing an increased interest for floating offshore applications. However, VAWT development is hindered by the lack of fast, accurate and validated simulation models. This work compares six different numerical models for VAWTS: a multiple...

  4. Numerical Simulations of a VAWT in the Wake of a Moving Car

    Directory of Open Access Journals (Sweden)

    Wenlong Tian

    2017-04-01

    Full Text Available Wind energy generated from the wake of moving cars has a large energy potential that has not yet been utilized. In this study, a vertical axis wind turbine (VAWT was used to recover energy from the wakes of moving cars. The turbine was designed to be planted by the side of the car lane and driven by the wake produced by the car. Transient computational fluid dynamics (CFD simulations were performed to evaluate the performance of the VAWT. The influence of two main factors on the performance of the VAWT, the velocity of the car and the gap between the car and the rotor, were studied. The simulations confirmed the feasibility of this plan, and in the tested cases, the VAWT was able to generate a maximum energy output of 100.49 J from the wake of a car. The results also showed that the performance of the VAWT decreased with the velocity of the car, and the increased gap between the car and the VAWT.

  5. INTEGRATED CORPORATE STRATEGY MODEL

    Directory of Open Access Journals (Sweden)

    CATALINA SORIANA SITNIKOV

    2014-02-01

    Full Text Available Corporations are at present operating in demanding and highly unsure periods, facing a mixture of increased macroeconomic need, competitive and capital market dangers, and in many cases, the prospect for significant technical and regulative gap. Throughout these demanding and highly unsure times, the corporations must pay particular attention to corporate strategy. In present times, corporate strategy must be perceived and used as a function of various fields, covers, and characters as well as a highly interactive system. For the corporation's strategy to become a competitive advantage is necessary to understand and also to integrate it in a holistic model to ensure sustainable progress of corporation activities under the optimum conditions of profitability. The model proposed in this paper is aimed at integrating the two strategic models, Hoshin Kanri and Integrated Strategy Model, as well as their consolidation with the principles of sound corporate governance set out by the OECD.

  6. Modeling and Interrogative Strategies.

    Science.gov (United States)

    Denney, Douglas R.

    Three studies to determine the effects of adult models on interrogative strategies of children (ages 6-11) are reviewed. Two issues are analyzed: (1) the comparative effectiveness of various types of modeling procedures for changing rule-governed behaviors, and (2) the interaction between observational learning and the developmental level of the…

  7. Effect of wind fluctuating on self-starting aerodynamics characteristics of VAWT

    Institute of Scientific and Technical Information of China (English)

    朱建阳; 蒋林; 赵慧

    2016-01-01

    The present work deals with an investigation of the self-starting aerodynamic characteristics of VAWT under fluctuating wind. In contrast to the previous studies, the rotational speed of the turbine is not fixed, the rotation of the turbine is determined by the dynamic interaction between the fluctuating wind and turbine. A weak coupling method is developed to simulate the dynamic interaction between the fluctuating wind and passive rotation turbine, and the results show that if the fluctuating wind with appropriate fluctuation amplitude and frequency, the self-starting aerodynamic characteristics of VAWT will be enhanced. It is also found that compared with the fluctuation amplitude, the fluctuation frequency of the variation in wind velocity is shown to have a minor effect on the performance of the turbine. The analysis will provide straightforward physical insight into the self-starting aerodynamic characteristics of VAWT under fluctuating wind.

  8. Flow Curvature Effects for VAWT: a Review of Virtual Airfoil Transformations and Implementation in XFOIL

    DEFF Research Database (Denmark)

    van der Horst, Sander; van de Wiel, Jelmer E.; Ferreira, Carlos Simao

    2016-01-01

    Blades on a Vertical Axis Wind Turbine (VAWT) experience curved streamlines, caused by the rotation of the turbine. This phenomenon is known as flow curvature and has effects on the aerodynamic loading of the blades. Several authors have proposed methods to account for flow curvature, resulting...

  9. Characteristics of future Vertical Axis Wind Turbines (VAWTs). [to generate utility grid electric power

    Science.gov (United States)

    Kadlec, E. G.

    1979-01-01

    The developing Darrieus VAWT technology whose ultimate objective is economically feasible, industry-produced, commercially marketed wind energy systems is reviewed. First-level aerodynamic, structural, and system analyses capabilities which support and evaluate the system designs are discussed. The characteristics of current technology designs are presented and their cost effectiveness is assessed. Potential improvements identified are also presented along with their cost benefits.

  10. SURF Model Calibration Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-10

    SURF and SURFplus are high explosive reactive burn models for shock initiation and propagation of detonation waves. They are engineering models motivated by the ignition & growth concept of high spots and for SURFplus a second slow reaction for the energy release from carbon clustering. A key feature of the SURF model is that there is a partial decoupling between model parameters and detonation properties. This enables reduced sets of independent parameters to be calibrated sequentially for the initiation and propagation regimes. Here we focus on a methodology for tting the initiation parameters to Pop plot data based on 1-D simulations to compute a numerical Pop plot. In addition, the strategy for tting the remaining parameters for the propagation regime and failure diameter is discussed.

  11. Inverse airfoil design method for low-speed straight-bladed Darrieus-type VAWT applications

    Energy Technology Data Exchange (ETDEWEB)

    Saeed, F. [King Fahd Univ. of Petroleum and Minerals, Dhahran (Saudi Arabia); Paraschivoiu, I.; Trifu, O. [Ecole Polytechnique, Montreal, PQ (Canada); Hess, M.; Gabrys, C. [Mariah Power Inc., Reno, NV (United States)

    2008-07-01

    Inverse airfoil design of a low-speed straight-bladed Darrieus-type vertical axis wind turbine (VAWT) can help improve aerodynamic performance and power output by eliminating undesirable flow field characteristics at very low Reynolds number. This study used an interactive inverse airfoil design method (PROFOIL) that allows specification of velocity and boundary-layer characteristics over different segments of the airfoil subject to constraints on the geometry (closure) and the flow field (far field boundary). Additional constraints were also considered to address pitching moment coefficient, thickness and the power output for a given tip-speed ratio. Performance analyses of the airfoil and the VAWT were carried out using state-of-the-art analyses codes XFOIL and CARDAAV, respectively. XFOIL is a panel method with a coupled boundary-layer scheme and is used to obtain the aerodynamic characteristics of resulting airfoil shapes. The final airfoil geometry is obtained through a multi-dimensional Newton iteration. The study showed that the strength of the method lies in the inverse design methodology whereas its weaknesses is in reliably predicting aerodynamic characteristics of airfoils at low Reynolds numbers and high angles of attack. A 10-15 per cent increase in the relative performance of the VAWT was achieved with this method. Although the results of the study showed that the method has great application potential for VAWTs in general, there is much room for improvement in flow analysis capabilities for low Re flows in reliably predicting post-stall aerodynamic characteristics. In the absence of such analysis capabilities, the authors suggested that the results should be viewed qualitatively and not quantitatively. 36 refs., 1 tab., 4 figs.

  12. A strategy model for management

    DEFF Research Database (Denmark)

    Friis, Ole Uhrskov; Holmgren, Jens; Eskildsen, Jacob Kjær

    2016-01-01

    Purpose: Developing a strategy model which explains what organisations should focus on in their strategy work, both in terms of the environment as well as how the strategy is implemented. In addition, the purpose is to demonstrate how this can influence and improve the organisations’ performance....

  13. Operational modal analysis on a VAWT in a large wind tunnel using stereo vision technique

    DEFF Research Database (Denmark)

    Najafi, Nadia; Schmidt Paulsen, Uwe

    2017-01-01

    This paper is about development and use of a research based stereo vision system for vibration and operational modal analysis on a parked, 1-kW, 3-bladed vertical axis wind turbine (VAWT), tested in a wind tunnel at high wind. Vibrations were explored experimentally by tracking small deflections...... of the markers on the structure with two cameras, and also numerically, to study structural vibrations in an overall objective to investigate challenges and to prove the capability of using stereo vision. Two high speed cameras provided displacement measurements at no wind speed interference. The displacement...

  14. Performance characteristics of a Vertical Axis Wind Turbine (VAWT) under transient conditions

    OpenAIRE

    Colley, Gareth; Mishra, Rakesh

    2011-01-01

    The present work investigates the performance characteristics of a novel Vertical Axis Wind Turbine (VAWT) for use in the urban environment. Here the performance of the wind turbine has been analyzed experimentally using a full scale prototype measuring 2.0m diameter and 1.0m in height. The turbine was located at the exit of a 0.6m x 0.6m wind tunnel section and was subjected to a jet flow. The performance output from the turbine has been obtained using a torque transducer unit which provides...

  15. Modelling strategy report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, P.A. [SAM Switzerland GmbH (Switzerland); Brommundt, J.; Mayer, G. [AF-Consult Switzerland Ltd, Baden (Switzerland)] [and others

    2012-01-15

    This report presents a preliminary plan for the development and application of models for the probabilistic sensitivity analyses and the deterministic calculation cases that will be used to analyse scenarios in the 2012 safety case. The plan addresses both groundwater flow modelling and radionuclide transport modelling, primarily of the repository near field and of the geosphere. It also addresses the measures that will be applied during the implementation and documentation of the calculations that will contribute to the quality assurance of the safety case. It is expected that this plan will be refined and amended as experience is gained during the carrying out of the work. (orig.)

  16. Modelling strategy report

    International Nuclear Information System (INIS)

    Smith, P.A.; Brommundt, J.; Mayer, G.

    2012-01-01

    This report presents a preliminary plan for the development and application of models for the probabilistic sensitivity analyses and the deterministic calculation cases that will be used to analyse scenarios in the 2012 safety case. The plan addresses both groundwater flow modelling and radionuclide transport modelling, primarily of the repository near field and of the geosphere. It also addresses the measures that will be applied during the implementation and documentation of the calculations that will contribute to the quality assurance of the safety case. It is expected that this plan will be refined and amended as experience is gained during the carrying out of the work. (orig.)

  17. Aerodynamic calculational methods for curved-blade Darrieus VAWT WECS

    Science.gov (United States)

    Templin, R. J.

    1985-03-01

    Calculation of aerodynamic performance and load distributions for curved-blade wind turbines is discussed. Double multiple stream tube theory, and the uncertainties that remain in further developing adequate methods are considered. The lack of relevant airfoil data at high Reynolds numbers and high angles of attack, and doubts concerning the accuracy of models of dynamic stall are underlined. Wind tunnel tests of blade airbrake configurations are summarized.

  18. TORNADO concept and realisation of a rotor for small VAWTs

    Directory of Open Access Journals (Sweden)

    Horia DUMITRESCU

    2013-09-01

    Full Text Available The concept of a three-tier configuration for a vertical axis rotor was successfully developed into a experimental model. The rotor assembly is divided into three tiers with three straight blades in each tier. The three-tiers are shifted by an angle of 400 generating a full helical flow field inside the rotor. Thereby the new configuration has some different mechanism of torque generation as other Darrieus rotors. The three-tier configuration facilitates the operation by enabling the turbine to self-start at wind velocity as low as 2 m/s with good performance and a smoother driving torque. At the same time the design couples an esthetic appearance with low noise level.

  19. Naesliden project: FEM modelling strategies

    Energy Technology Data Exchange (ETDEWEB)

    Borg, T.

    1980-05-15

    A schematized description is given of the different stages in the project. The aim is to show the development of the project and the strategies which have been chosen. The four different stages in the project are treated from the following points of view: the reasons for the choice of material models; the determination of model properties; and the control of the calculated values. In the origin plan for the project it was stated to only use a joint element model. However, it was shown to be a reasonable strategy to use both a general linear elastic model and a geometric restricted model with joint elements. During the course of the Project's development stages, it was found that a reduction in the number of rock types could be made without loss of generality. A modified strategy is suggested based on more studies of the rock bahavior and less advanced calculations in the first stages of the project.

  20. Optimal Strategy and Business Models

    DEFF Research Database (Denmark)

    Johnson, Peter; Foss, Nicolai Juul

    2016-01-01

    This study picks up on earlier suggestions that control theory may further the study of strategy. Strategy can be formally interpreted as an idealized path optimizing heterogeneous resource deployment to produce maximum financial gain. Using standard matrix methods to describe the firm Hamiltonia...... variable of firm path, suggesting in turn that the firm's business model is the codification of the application of investment resources used to control the strategic path of value realization....

  1. Aerodynamic modeling of floating vertical axis wind turbines using the actuator cylinder flow method

    DEFF Research Database (Denmark)

    Cheng, Zhengshun; Aagaard Madsen, Helge; Gao, Zhen

    2016-01-01

    Recently the interest in developing vertical axis wind turbines (VAWTs) for offshore application has been increasing. Among the aerodynamic models of VAWTs, double multi-streamtube (DMST) and actuator cylinder (AC) models are two favorable methods for fully coupled modeling and dynamic analysis...

  2. Strain gauge validation experiments for the Sandia 34-meter VAWT (Vertical Axis Wind Turbine) test bed

    Science.gov (United States)

    Sutherland, Herbert J.

    1988-08-01

    Sandia National Laboratories has erected a research oriented, 34- meter diameter, Darrieus vertical axis wind turbine near Bushland, Texas. This machine, designated the Sandia 34-m VAWT Test Bed, is equipped with a large array of strain gauges that have been placed at critical positions about the blades. This manuscript details a series of four-point bend experiments that were conducted to validate the output of the blade strain gauge circuits. The output of a particular gauge circuit is validated by comparing its output to equivalent gauge circuits (in this stress state) and to theoretical predictions. With only a few exceptions, the difference between measured and predicted strain values for a gauge circuit was found to be of the order of the estimated repeatability for the measurement system.

  3. Speed and Torque Control Strategies for Loss Reduction of Vertical Axis Wind Turbines

    Science.gov (United States)

    Argent, Michael; McDonald, Alasdair; Leithead, Bill; Giles, Alexander

    2016-09-01

    This paper builds on the work into modelling the generator losses for Vertical Axis Wind Turbines from their intrinsic torque cycling to investigate the effects of aerodynamic inefficiencies caused by the varying rotational speed resulting from different torque control strategies to the cyclic torque. This is achieved by modelling the wake that builds up from the rotation of the VAWT rotor to investigate how the wake responds to a changing rotor speed and how this in turn affects the torque produced by the blades as well as the corresponding change in generator losses and any changes to the energy extracted by the wind turbine rotor.

  4. A fully coupled method for numerical modeling and dynamic analysis of floating vertical axis wind turbines

    DEFF Research Database (Denmark)

    Cheng, Zhengshun; Aagaard Madsen, Helge; Gao, Zhen

    2017-01-01

    •Aerodynamic modeling of floating VAWTs is established using the Actuator Cylinder (AC) flow method.•A fully coupled aero-hydro-servo-elastic simulation tool, i.e. SIMO-RIFLEX-AC, is developed for floating VAWTs.•The developedsimulation tool is verified to be accurate by a series of code-to-code ...

  5. A Strategy Modelling Technique for Financial Services

    OpenAIRE

    Heinrich, Bernd; Winter, Robert

    2004-01-01

    Strategy planning processes often suffer from a lack of conceptual models that can be used to represent business strategies in a structured and standardized form. If natural language is replaced by an at least semi-formal model, the completeness, consistency, and clarity of strategy descriptions can be drastically improved. A strategy modelling technique is proposed that is based on an analysis of modelling requirements, a discussion of related work and a critical analysis of generic approach...

  6. Intersections between strategy and business models

    OpenAIRE

    磯村 和人

    2015-01-01

    This paper explores the relationship between strategy and business models. I review major researches on strategy and business models to provide a viewpoint to consider the intersections between them. The theory of strategy shifts the focus from visible competitive advantage to its internal managerial resources. The concept of business models has been discussed because a business model is considered to be a combination of internal and external business processes; it clarifies how to effectivel...

  7. Business model or strategy: which comes first?

    DEFF Research Database (Denmark)

    Friis, Jesper Deleuran; Lueg, Rainer; Mayanja, Remmy

    2015-01-01

    There is an ongoing debate on how the concepts of strategy and business models relate to each other. Specifically, it is a puzzle whether business models determine strategies, or whether strategies precede business models (Seddon et al., 2004). Based on recent conceptual considerations (Cavalcante...... et al., 2011), the authors attempt to solve this puzzle by considering their mutual influence at different stages of the company’s business lifecycle. For that, the auhors use Scandinavian Software Company (SSC) as a case study. The initial idea of a business model is shown to shape SSC’s strategy...... in the birth phase. It is then argued that this relationship changed as SSC entered its growth phase and met competition, and the product market strategy determined the change in the business model. The researchers contribute to the currently underexplored dynamic relationship of business models and strategies...

  8. The Motive--Strategy Congruence Model Revisited.

    Science.gov (United States)

    Watkins, David; Hattie, John

    1992-01-01

    Research with 1,266 Australian secondary school students supports 2 propositions critical to the motive-strategy congruence model of J. B. Biggs (1985). Students tend to use learning strategies congruent with motivation for learning, and congruent motive-strategy combinations are associated with higher average school grades. (SLD)

  9. Mining Social Entrepreneurship Strategies Using Topic Modeling.

    Directory of Open Access Journals (Sweden)

    Yanto Chandra

    Full Text Available Despite the burgeoning research on social entrepreneurship (SE, SE strategies remain poorly understood. Drawing on extant research on the social activism and social change, empowerment and SE models, we explore, classify and validate the strategies used by 2,334 social entrepreneurs affiliated with the world's largest SE support organization, Ashoka. The results of the topic modeling of the social entrepreneurs' strategy profiles reveal that they employed a total of 39 change-making strategies that vary across resources (material versus symbolic strategies, specificity (general versus specific strategies, and mode of participation (mass versus elite participation strategies; they also vary across fields of practice and time. Finally, we identify six meta-SE strategies-a reduction from the 39 strategies-and identify four new meta-SE strategies (i.e., system reform, physical capital development, evidence-based practices, and prototyping that have been overlooked in prior SE research. Our findings extend and deepen the research into SE strategies and offer a comprehensive model of SE strategies that advances theory, practice and policy making.

  10. Mining Social Entrepreneurship Strategies Using Topic Modeling.

    Science.gov (United States)

    Chandra, Yanto; Jiang, Li Crystal; Wang, Cheng-Jun

    2016-01-01

    Despite the burgeoning research on social entrepreneurship (SE), SE strategies remain poorly understood. Drawing on extant research on the social activism and social change, empowerment and SE models, we explore, classify and validate the strategies used by 2,334 social entrepreneurs affiliated with the world's largest SE support organization, Ashoka. The results of the topic modeling of the social entrepreneurs' strategy profiles reveal that they employed a total of 39 change-making strategies that vary across resources (material versus symbolic strategies), specificity (general versus specific strategies), and mode of participation (mass versus elite participation strategies); they also vary across fields of practice and time. Finally, we identify six meta-SE strategies-a reduction from the 39 strategies-and identify four new meta-SE strategies (i.e., system reform, physical capital development, evidence-based practices, and prototyping) that have been overlooked in prior SE research. Our findings extend and deepen the research into SE strategies and offer a comprehensive model of SE strategies that advances theory, practice and policy making.

  11. Performance of hedging strategies in interval models

    NARCIS (Netherlands)

    Roorda, Berend; Engwerda, Jacob; Schumacher, J.M.

    2005-01-01

    For a proper assessment of risks associated with the trading of derivatives, the performance of hedging strategies should be evaluated not only in the context of the idealized model that has served as the basis of strategy development, but also in the context of other models. In this paper we

  12. Mining Social Entrepreneurship Strategies Using Topic Modeling

    Science.gov (United States)

    2016-01-01

    Despite the burgeoning research on social entrepreneurship (SE), SE strategies remain poorly understood. Drawing on extant research on the social activism and social change, empowerment and SE models, we explore, classify and validate the strategies used by 2,334 social entrepreneurs affiliated with the world’s largest SE support organization, Ashoka. The results of the topic modeling of the social entrepreneurs’ strategy profiles reveal that they employed a total of 39 change-making strategies that vary across resources (material versus symbolic strategies), specificity (general versus specific strategies), and mode of participation (mass versus elite participation strategies); they also vary across fields of practice and time. Finally, we identify six meta-SE strategies―a reduction from the 39 strategies―and identify four new meta-SE strategies (i.e., system reform, physical capital development, evidence-based practices, and prototyping) that have been overlooked in prior SE research. Our findings extend and deepen the research into SE strategies and offer a comprehensive model of SE strategies that advances theory, practice and policy making. PMID:26998970

  13. Strategies for developing competency models.

    Science.gov (United States)

    Marrelli, Anne F; Tondora, Janis; Hoge, Michael A

    2005-01-01

    There is an emerging trend within healthcare to introduce competency-based approaches in the training, assessment, and development of the workforce. The trend is evident in various disciplines and specialty areas within the field of behavioral health. This article is designed to inform those efforts by presenting a step-by-step process for developing a competency model. An introductory overview of competencies, competency models, and the legal implications of competency development is followed by a description of the seven steps involved in creating a competency model for a specific function, role, or position. This modeling process is drawn from advanced work on competencies in business and industry.

  14. Modeling Business Strategy: A Consumer Value Perspective

    OpenAIRE

    Svee , Eric-Oluf; Giannoulis , Constantinos; Zdravkovic , Jelena

    2011-01-01

    Part 3: Business Modeling; International audience; Business strategy lays out the plan of an enterprise to achieve its vision by providing value to its customers. Typically, business strategy focuses on economic value and its relevant exchanges with customers and does not directly address consumer values. However, consumer values drive customers’ choices and decisions to use a product or service, and therefore should have a direct impact on business strategy. This paper explores whether and h...

  15. Modeling Human Information Acquisition Strategies

    NARCIS (Netherlands)

    Heuvelink, Annerieke; Klein, Michel C. A.; van Lambalgen, Rianne; Taatgen, Niels A.; Rijn, Hedderik van

    2009-01-01

    The focus of this paper is the development of a computational model for intelligent agents that decides on whether to acquire required information by retrieving it from memory or by interacting with the world. First, we present a task for which such decisions have to be made. Next, we discuss an

  16. Learning strategies: a synthesis and conceptual model

    Science.gov (United States)

    Hattie, John A. C.; Donoghue, Gregory M.

    2016-08-01

    The purpose of this article is to explore a model of learning that proposes that various learning strategies are powerful at certain stages in the learning cycle. The model describes three inputs and outcomes (skill, will and thrill), success criteria, three phases of learning (surface, deep and transfer) and an acquiring and consolidation phase within each of the surface and deep phases. A synthesis of 228 meta-analyses led to the identification of the most effective strategies. The results indicate that there is a subset of strategies that are effective, but this effectiveness depends on the phase of the model in which they are implemented. Further, it is best not to run separate sessions on learning strategies but to embed the various strategies within the content of the subject, to be clearer about developing both surface and deep learning, and promoting their associated optimal strategies and to teach the skills of transfer of learning. The article concludes with a discussion of questions raised by the model that need further research.

  17. Wind farm models and control strategies

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, Poul; Hansen, Anca D.; Iov, F.; Blaabjerg, F.; Donovan, M.H.

    2005-08-01

    This report describes models and control strategies for 3 different concepts of wind farms. Initially, the potential in improvement of grid integration, structural loads and energy production is investigated in a survey of opportunities. Then simulation models are described, including wind turbine models for a fixed speed wind turbine with active stall control and a variable speed wind turbine with doubly-fed induction generator. After that, the 3 wind farm concepts and control strategies are described. The 3 concepts are AC connected doubly fed turbines, AC connected active stall turbines and DC connected active stall turbines. Finally, some simulation examples and conclusions are presented. (au)

  18. Supply chain strategies, issues and models

    CERN Document Server

    Ramanathan, Ramakrishnan

    2014-01-01

    In the 21st century, supply chain operations and relationships among supply chain partners have become highly challenging, necessitating new approaches, e.g., the development of new models. Supply Chain Strategies, Issues and Models discusses supply chain issues and models with examples from actual industrial cases. Expert authors with a wide spectrum of knowledge working in various areas of supply chain management from various geographical locations offer refreshing, novel and insightful ideas and address possible solutions using established theories and models. Supply Chain Strategies, Issues and Models features studies that have used mathematical modeling, statistical analyses and also descriptive qualitative studies. The chapters cover many relevant themes related to supply chains and logistics including supply chain complexity, information sharing, quality (six sigma), electronic Kanbans, inventory models, scheduling, purchasing and contracts. To facilitate easy reading, the chapters that deal with suppl...

  19. The Strategies of Modeling in Biology Education

    Science.gov (United States)

    Svoboda, Julia; Passmore, Cynthia

    2013-01-01

    Modeling, like inquiry more generally, is not a single method, but rather a complex suite of strategies. Philosophers of biology, citing the diverse aims, interests, and disciplinary cultures of biologists, argue that modeling is best understood in the context of its epistemic aims and cognitive payoffs. In the science education literature,…

  20. Improved double-multiple streamtube model for the Darrieus-type vertical axis wind turbine

    Science.gov (United States)

    Berg, D. E.

    Double streamtube codes model the curved blade (Darrieus-type) vertical axis wind turbine (VAWT) as a double actuator fish arrangement (one half) and use conservation of momentum principles to determine the forces acting on the turbine blades and the turbine performance. Sandia National Laboratories developed a double multiple streamtube model for the VAWT which incorporates the effects of the incident wind boundary layer, nonuniform velocity between the upwind and downwind sections of the rotor, dynamic stall effects and local blade Reynolds number variations. The theory underlying this VAWT model is described, as well as the code capabilities. Code results are compared with experimental data from two VAWT's and with the results from another double multiple streamtube and a vortex filament code. The effects of neglecting dynamic stall and horizontal wind velocity distribution are also illustrated.

  1. Modeling and Generating Strategy Games Mechanics

    DEFF Research Database (Denmark)

    Mahlmann, Tobias

    of the game is, how players may manipulate the game world, etc. We present the Strategy Games Description Language (SGDL), a tree-based approach to model the game mechanics of strategy games. SGDL allows game designers to rapid prototype their game ideas with the help of our customisable game engine. We...... their games to individual players’ preferences by creating game content adaptively to how the player plays (and likes) a game. W we extend the notion of “procedural game content generation” by “game mechanics”. Game mechanics herein refer to the way that objects in a game may interact, what the goal...... present several example games to demonstrate the capabilities of the language and how to model common strategy game elements. Furthermore, we present methods to procedurally generate and evaluate game mechanics modelled in SGDL in terms of enjoyability. We argue that an evolutionary process can be used...

  2. High burnup issues and modelling strategies

    International Nuclear Information System (INIS)

    Dutta, B.K.

    2005-01-01

    The performance of high burnup fuel is affected by a number of phenomena, such as, conductivity degradation, modified radial flux profile, fission gas release from high burnup structures, PCMI, burnup dependent thermo-mechanical properties, etc. The modelling strategies of some of these phenomena are available in literature. These can be readily incorporated in a fuel modelling performance code. The computer code FAIR has been developed in BARC over the years to evaluate the fuel performance at extended burnup and modelling of the fuel rods for advanced fuel cycles. The present paper deals with the high burnup issues in the fuel pins, their modelling strategies and results of the case studies specifically involving high burnup fuel. (author)

  3. Modelling emergent trophic strategies in plankton

    DEFF Research Database (Denmark)

    Andersen, Ken Haste; Aksnes, Dag L.; Berge, Terje

    2015-01-01

    Plankton are typically divided into phytoplankton and zooplankton in marine ecosystem models. Yet, most protists in the photic zone engage in some degree of phagotrophy, and it has been suggested that trophic strategy is really a continuum between pure phototrophs (phytoplankton) and pure...

  4. Persistence Modeling for Assessing Marketing Strategy Performance

    NARCIS (Netherlands)

    M.G. Dekimpe (Marnik); D.M. Hanssens (Dominique)

    2003-01-01

    textabstractThe question of long-run market response lies at the heart of any marketing strategy that tries to create a sustainable competitive advantage for the firm or brand. A key challenge, however, is that only short-run results of marketing actions are readily observable. Persistence modeling

  5. Individual Hearing Loss: Characterization, Modelling, Compensation Strategies

    DEFF Research Database (Denmark)

    Santurette, Sébastien; Dau, Torsten; Christensen-Dalsgaard, Jakob

    2016-01-01

    account for such individual differences, which make it challenging to find adequate compensation strategies in hearing devices. How to characterize, model, and compensate for individual hearing loss were the main topics of the fifth International Symposium on Auditory and Audiological Research (ISAAR...

  6. Site descriptive modelling - strategy for integrated evaluation

    International Nuclear Information System (INIS)

    Andersson, Johan

    2003-02-01

    The current document establishes the strategy to be used for achieving sufficient integration between disciplines in producing Site Descriptive Models during the Site Investigation stage. The Site Descriptive Model should be a multidisciplinary interpretation of geology, rock mechanics, thermal properties, hydrogeology, hydrogeochemistry, transport properties and ecosystems using site investigation data from deep bore holes and from the surface as input. The modelling comprise the following iterative steps, evaluation of primary data, descriptive and quantitative modelling (in 3D), overall confidence evaluation. Data are first evaluated within each discipline and then the evaluations are checked between the disciplines. Three-dimensional modelling (i.e. estimating the distribution of parameter values in space and its uncertainty) is made in a sequence, where the geometrical framework is taken from the geological model and in turn used by the rock mechanics, thermal and hydrogeological modelling etc. The three-dimensional description should present the parameters with their spatial variability over a relevant and specified scale, with the uncertainty included in this description. Different alternative descriptions may be required. After the individual discipline modelling and uncertainty assessment a phase of overall confidence evaluation follows. Relevant parts of the different modelling teams assess the suggested uncertainties and evaluate the feedback. These discussions should assess overall confidence by, checking that all relevant data are used, checking that information in past model versions is considered, checking that the different kinds of uncertainty are addressed, checking if suggested alternatives make sense and if there is potential for additional alternatives, and by discussing, if appropriate, how additional measurements (i.e. more data) would affect confidence. The findings as well as the modelling results are to be documented in a Site Description

  7. Politeness Strategies Used in Requests--A Cybernetic Model.

    Science.gov (United States)

    Kitao, Kenji

    This paper discusses a cybernetic model of politeness strategies used in the process of making a request. The concept of systems, cybernetic models, and politeness strategies are reviewed, and the way they work together in the proposed model is examined. Politeness strategies are communication strategies used to change behavior enough to achieve…

  8. Combined optimization model for sustainable energization strategy

    Science.gov (United States)

    Abtew, Mohammed Seid

    Access to energy is a foundation to establish a positive impact on multiple aspects of human development. Both developed and developing countries have a common concern of achieving a sustainable energy supply to fuel economic growth and improve the quality of life with minimal environmental impacts. The Least Developing Countries (LDCs), however, have different economic, social, and energy systems. Prevalence of power outage, lack of access to electricity, structural dissimilarity between rural and urban regions, and traditional fuel dominance for cooking and the resultant health and environmental hazards are some of the distinguishing characteristics of these nations. Most energy planning models have been designed for developed countries' socio-economic demographics and have missed the opportunity to address special features of the poor countries. An improved mixed-integer programming energy-source optimization model is developed to address limitations associated with using current energy optimization models for LDCs, tackle development of the sustainable energization strategies, and ensure diversification and risk management provisions in the selected energy mix. The Model predicted a shift from traditional fuels reliant and weather vulnerable energy source mix to a least cost and reliable modern clean energy sources portfolio, a climb on the energy ladder, and scored multifaceted economic, social, and environmental benefits. At the same time, it represented a transition strategy that evolves to increasingly cleaner energy technologies with growth as opposed to an expensive solution that leapfrogs immediately to the cleanest possible, overreaching technologies.

  9. COMMUNICATION STRATEGY ABOUT BUSINESS MODELS: STAKEHOLDERS PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    Bojoagă Alexandru

    2013-07-01

    Full Text Available Organizations inform stakeholders about their current and future activities, processes, created value, strategic intentions, and other information that may influence the established relationships. Organizations choose to communicate with stakeholders by different means and in varied ways. The annual report represents a way of communicating between companies and their stakeholders, and it is offering comprehensive information about how companies operates and creates value. The business model is an emerging concept in management literature and practice. The concept describes the logic by which a organization creates, maintains and delivers value for its stakeholders. Through annual reports organisations can communicate to stakeholders information about their business models.We investigated how information about business models is explicitly communicated through annual reports, and how this information is reffering to stakeholders. Our paper aims to reveal which stakeholders are more often mentioned when organizations are communicating about business models through annual reports. This approach shows the attention degree given by organizations to stakeholders. We perceived this from a strategic point of view, as a strategic signal. Thus, we considered if the stakeholder is mentioned more frequent in the communicated message it has a greater role in communication strategy about business model. We conducted an exploratory research and have realized a content analysis.The analysed data consist in over a thousand annual reports from 96 organizations. We analysed the informations transmitted by organizations through annual reports. The annual reports were for a time period of 12 years. Most of the selected companies are multi-business, and are operating in different industries. The results show the stakeholder’s hierarchy based on how often they were mentioned in the communicated messages about business models through annual reports. Based on our

  10. New Modelling Strategies For Metal Cutting

    International Nuclear Information System (INIS)

    Rosa, Pedro A. R.; Martins, Paulo A. F.; Atkins, Anthony G.

    2007-01-01

    This paper draws from the 'plasticity and friction only' view of metal cutting to the presentation of new modelling strategies based on the interaction between finite elements and modern ductile fracture mechanics. The overall presentation is supported by specially designed orthogonal metal cutting experiments that were performed on Lead test specimens under laboratory-controlled conditions. Comparisons between theoretical predictions and experimental results comprise a wide range of topics such as material flow, cutting forces and specific cutting pressure. The paper demonstrates that while material flow and chip formation can be successfully modelled by traditional 'plasticity and friction only' analyses, the contribution of the fracture work involved in the formation of new surfaces is essential for obtaining good estimates of cutting forces and of the specific cutting pressure

  11. A free wake vortex lattice model for vertical axis wind turbines: Modeling, verification and validation

    International Nuclear Information System (INIS)

    Meng, Fanzhong; Schwarze, Holger; Vorpahl, Fabian; Strobel, Michael

    2014-01-01

    Since the 1970s several research activities had been carried out on developing aerodynamic models for Vertical Axis Wind Turbines (VAWTs). In order to design large VAWTs of MW scale, more accurate aerodynamic calculation is required to predict their aero-elastic behaviours. In this paper, a 3D free wake vortex lattice model for VAWTs is developed, verified and validated. Comparisons to the experimental results show that the 3D free wake vortex lattice model developed is capable of making an accurate prediction of the general performance and the instantaneous aerodynamic forces on the blades. The comparison between momentum method and the vortex lattice model shows that free wake vortex models are needed for detailed loads calculation and for calculating highly loaded rotors

  12. A normative model for assessing competitive strategy

    OpenAIRE

    Ungerer, Gerard David; Cayzer, Steve

    2016-01-01

    The hyper-competitive nature of e-business has raised the need for a generic way to appraise the merit of a developed business strategy. Although progress has been made in the domain of strategy evaluation, the established literature differs over the ‘tests’ that a strategy must pass to be considered well-constructed. This paper therefore investigates the existing strategy-evaluation literature to propose a more integrated and comprehensive normative strategic assessment that can be used to e...

  13. Effectiveness of two-dimensional CFD simulations for Darrieus VAWTs: a combined numerical and experimental assessment

    International Nuclear Information System (INIS)

    Bianchini, Alessandro; Balduzzi, Francesco; Bachant, Peter; Ferrara, Giovanni; Ferrari, Lorenzo

    2017-01-01

    Highlights: • 2D CFD simulations compared to experimental tow-tank data on the RVAT test model. • The use of CFD with open-field-like boundaries is suggested. • A reliable estimation of the turbine performance and the wake structure is obtained. • The transitional turbulence model is recommended for low TSRs and/or small rotors. • The wake analysis identified the main vortical structures generated by the blades. - Abstract: Thanks to the continuous improvement of calculation resources, computational fluid dynamics (CFD) is expected to provide in the next few years a cost-effective and accurate tool to improve the understanding of the unsteady aerodynamics of Darrieus wind turbines. This rotor type is in fact increasingly welcome by the wind energy community, especially in case of small size applications and/or non-conventional installation sites. In the present study, unique tow tank experimental data on the performance curve and the near-wake structure of a Darrieus rotor were used as a benchmark to validate the effectiveness of different CFD approaches. In particular, a dedicated analysis is provided to assess the suitability, the effectiveness and the future prospects of simplified two-dimensional (2D) simulations. The correct definition of the computational domain, the selection of the turbulence models and the correction of simulated data for the parasitic torque components are discussed in this study. Results clearly show that, (only) if properly set, two-dimensional CFD simulations are able to provide - with a reasonable computational cost - an accurate estimation of the turbine performance and also quite reliably describe the attended flow-field around the rotor and its wake.

  14. A normative model for assessing competitive strategy

    Directory of Open Access Journals (Sweden)

    Ungerer, Gerard David

    2016-12-01

    Full Text Available The hyper-competitive nature of e-business has raised the need for a generic way to appraise the merit of a developed business strategy. Although progress has been made in the domain of strategy evaluation, the established literature differs over the ‘tests’ that a strategy must pass to be considered well-constructed. This paper therefore investigates the existing strategy-evaluation literature to propose a more integrated and comprehensive normative strategic assessment that can be used to evaluate and refine a business’ s competitive strategy , adding to its robustness and survivability.

  15. Toward an Integrative Model of Global Business Strategy

    DEFF Research Database (Denmark)

    Li, Xin

    fragmentation-integration-fragmentation-integration upward spiral. In response to the call for integrative approach to strategic management research, we propose an integrative model of global business strategy that aims at integrating not only strategy and IB but also the different paradigms within the strategy...... field. We also discuss the merit and limitation of our model....

  16. Fostering Transfer of Study Strategies: A Spiral Model.

    Science.gov (United States)

    Davis, Denise M.; Clery, Carolsue

    1994-01-01

    Describes the design and implementation of a Spiral Model for the introduction and repeated practice of study strategies, based on Taba's model for social studies. In a college reading and studies strategies course, key strategies were introduced early and used through several sets of humanities and social and physical sciences readings. (Contains…

  17. Unsteady flow field in a mini VAWT with relative rotation blades: analysis of temporal results

    International Nuclear Information System (INIS)

    Bayeul-Lainé, A C; Simonet, S; Bois, G

    2013-01-01

    The present wind turbine is a small one which can be used on roofs or in gardens. This turbine has a vertical axis. Each turbine blade combines a rotating movement around its own axis and around the main rotor axis. Due to this combination of movements, flow around this turbine is highly unsteady and needs to be modelled by unsteady calculation. The present work is an extended study starting in 2009. The benefits of combined rotating blades have been shown. The performance coefficient of this kind of turbine is very good for some blade stagger angles. Spectral analysis of unsteady results on specific points in the domain and temporal forces on blades was already presented for elliptic blades. The main aim here is to compare two kinds of blades in case of the best performances

  18. Modeling and Generating Strategy Games Mechanics

    OpenAIRE

    Mahlmann, Tobias

    2013-01-01

    Strategy games are a popular genre of games with a long history, originatingfrom games like Chess or Go. The first strategy games were published as“Kriegspiele” (engl. wargames) in the late 18th century, intended for the education of young cadets. Since then strategy games were refined and transformed over two centuries into a medium of entertainment. Today’s computer strategy games have their roots in the board- and roleplaying games of the 20th century and enjoy great popularity. We use str...

  19. Precommitted Investment Strategy versus Time-Consistent Investment Strategy for a Dual Risk Model

    Directory of Open Access Journals (Sweden)

    Lidong Zhang

    2014-01-01

    Full Text Available We are concerned with optimal investment strategy for a dual risk model. We assume that the company can invest into a risk-free asset and a risky asset. Short-selling and borrowing money are allowed. Due to lack of iterated-expectation property, the Bellman Optimization Principle does not hold. Thus we investigate the precommitted strategy and time-consistent strategy, respectively. We take three steps to derive the precommitted investment strategy. Furthermore, the time-consistent investment strategy is also obtained by solving the extended Hamilton-Jacobi-Bellman equations. We compare the precommitted strategy with time-consistent strategy and find that these different strategies have different advantages: the former can make value function maximized at the original time t=0 and the latter strategy is time-consistent for the whole time horizon. Finally, numerical analysis is presented for our results.

  20. Return models and dynamic asset allocation strategies

    OpenAIRE

    Shi, Wyanet Wen

    2017-01-01

    This thesis studies the design of optimal investment strategies. A strategy is considered optimal when it minimizes the variance of terminal portfolio wealth for a given level of expected terminal portfolio wealth, or equivalently, maximizes an investor's utility. We study this issue in two particular situations: when asset returns follow a continuous-time path-independent process, and when they follow a discrete-time path-dependent process. Continuous-time path-independent return mode...

  1. Precommitted Investment Strategy versus Time-Consistent Investment Strategy for a General Risk Model with Diffusion

    Directory of Open Access Journals (Sweden)

    Lidong Zhang

    2014-01-01

    Full Text Available We mainly study a general risk model and investigate the precommitted strategy and the time-consistent strategy under mean-variance criterion, respectively. A lagrange method is proposed to derive the precommitted investment strategy. Meanwhile from the game theoretical perspective, we find the time-consistent investment strategy by solving the extended Hamilton-Jacobi-Bellman equations. By comparing the precommitted strategy with the time-consistent strategy, we find that the company under the time-consistent strategy has to give up the better current utility in order to keep a consistent satisfaction over the whole time horizon. Furthermore, we theoretically and numerically provide the effect of the parameters on these two optimal strategies and the corresponding value functions.

  2. Electric Circuit Model for the Aerodynamic Performance Analysis of a Three-Blade Darrieus-Type Vertical Axis Wind Turbine: The Tchakoua Model

    Directory of Open Access Journals (Sweden)

    Pierre Tchakoua

    2016-10-01

    Full Text Available The complex and unsteady aerodynamics of vertical axis wind turbines (VAWTs pose significant challenges for simulation tools. Recently, significant research efforts have focused on the development of new methods for analysing and optimising the aerodynamic performance of VAWTs. This paper presents an electric circuit model for Darrieus-type vertical axis wind turbine (DT-VAWT rotors. The novel Tchakoua model is based on the mechanical description given by the Paraschivoiu double-multiple streamtube model using a mechanical‑electrical analogy. Model simulations were conducted using MATLAB for a three-bladed rotor architecture, characterized by a NACA0012 profile, an average Reynolds number of 40,000 for the blade and a tip speed ratio of 5. The results obtained show strong agreement with findings from both aerodynamic and computational fluid dynamics (CFD models in the literature.

  3. A Model of Dynamic Strategy-Making

    DEFF Research Database (Denmark)

    Andersen, Torben Juul; Hallin, Carina Antonia; Li, Xin

    The organizational capacity to cope with unexpected changes remains a fundamental challenge in strategy as global competition and technological innovation increase environmental uncertainty. Conventional strategy-making is often conceived as a sequential linear process where we see it as a non......-linear interaction between top-down and bottom-up mechanisms dealing with multiple actions taken throughout the organization over time. It is driven by intension but with a flexible balance between centralized (planned) and decentralized (spontaneous) activities. We adopt the principles of complementary Yin......-Yang elements and Zhong Yong balance to explain the time bound interaction between these opposing yet complementary strategy-making mechanisms where tradeoffs and synergies are balanced across hierarchical levels....

  4. Criticism and Counter-Criticism of Public Management: Strategy Models

    OpenAIRE

    Luis C. Ortigueira

    2007-01-01

    Critical control is very important in scientific management. This paper presents models of critical and counter-critical public-management strategies, focusing on the types of criticism and counter-criticism manifested in parliamentary political debates. The paper includes: (i) a normative model showing how rational criticism can be carried out; (ii) a normative model for oral critical intervention; and (iii) a general motivational strategy model for criticisms and counter-criticisms. The pap...

  5. Modeling Strategies for Enhancing Educational Quality

    Science.gov (United States)

    Cummings, William K.; Bain, Olga

    2017-01-01

    With the strengthening of the global economy, contemporary societies have come to view the educational achievements of their young people as a major component of national competiveness. But there are substantial variations in the strategies employed by different nations. To maximize educational achievements, some nations believe that the provision…

  6. Model Strategi Pemasaran Jasa Konsultansi Kontraktor Di Kalimantan Selatan

    Directory of Open Access Journals (Sweden)

    Candra Yuliana

    2018-01-01

    Full Text Available Most of the general public of service users have not understood the value of construction consultancy services. This inhibits market opportunities in the private sector for construction consulting services particularly in South Kalimantan. The objective of the research is to create an appropriate marketing strategy for corporation construction consultancy services in South Kalimantan.Strategies can be identified by SWOT analysis, AHP analysis and Importance Performance Analysis. This research is done by giving questionnaire to the service users and construction consulting firms in South Kalimantan. The result of the research are, a model of the marketing strategy of the construction consulting service, Strength-Opportunity strategy, grow and build strategy, service pricing strategy, and a basic strategy. This is a collaboration between the marketing-mix and service quality. Key words: AHP, construction consulting service, marketing strategy, SWOT

  7. Site Closure Strategy Model for Creosote Site

    International Nuclear Information System (INIS)

    Coll, F.R.; Gray, D.R.

    2009-01-01

    In conjunction with RCRA site corrective action at an active wood preserving facility, a risk-based site closure strategy was developed and incorporated the performance of a dense non-aqueous phase liquid (DNAPL) source recovery remedy, a monitored natural attenuation (MNA) remedy for dissolved phase groundwater, and institutional controls. Innovative creosote DNAPL source recovery has been undertaken at the Site since 1998. Pooled creosote DNAPL is present 90 feet below ground within a transmissive sand and gravel aquifer with a saturated thickness of approximately 80 feet. The creosote DNAPL source is situated on the property boundary of the site and has generated a 1/2 mile off-site dissolved phase plume, creating significant NAPL management and remedial technology verification issues. To date, over 120,000 gallons of creosote DNAPL have been recovered from the subsurface utilizing a modified circulation well technology. A mass discharge flux protocol was developed to serve as a major performance metrics for the continuation of source removal efforts and to support the application of monitored natural attenuation as an associated remedial technology for groundwater. The mass removal success has supported the MNA remedy for dissolved phase groundwater and the associated development of institutional controls. The enacted site management strategy outlines the current and future risk management activities for the Site and represents an appropriate site closure strategy for the Site. (authors)

  8. An Integrative Model of Internationalization Strategies

    DEFF Research Database (Denmark)

    Li, Xin; Gammelgaard, Jens

    2012-01-01

    This paper critically reviews the ownership, location, and internalization (OLI) model, and the Uppsala internationalization process (UIP) framework. Both the OLI model and the UIP model ignore to incorporate the insights of each other and fail to include corporate entrepreneurship in their analy...

  9. Audiovisual preservation strategies, data models and value-chains

    OpenAIRE

    Addis, Matthew; Wright, Richard

    2010-01-01

    This is a report on preservation strategies, models and value-chains for digital file-based audiovisual content. The report includes: (a)current and emerging value-chains and business-models for audiovisual preservation;(b) a comparison of preservation strategies for audiovisual content including their strengths and weaknesses, and(c) a review of current preservation metadata models, and requirements for extension to support audiovisual files.

  10. Alpha-modeling strategy for LES of turbulent mixing

    NARCIS (Netherlands)

    Geurts, Bernard J.; Holm, Darryl D.; Drikakis, D.; Geurts, B.J.

    2002-01-01

    The α-modeling strategy is followed to derive a new subgrid parameterization of the turbulent stress tensor in large-eddy simulation (LES). The LES-α modeling yields an explicitly filtered subgrid parameterization which contains the filtered nonlinear gradient model as well as a model which

  11. A stochastic model for intermittent search strategies

    International Nuclear Information System (INIS)

    Benichou, O; Coppey, M; Moreau, M; Suet, P H; Voituriez, R

    2005-01-01

    It is often necessary, in scientific or everyday life problems, to find a randomly hidden target. What is then the optimal strategy to reach it as rapidly as possible? In this article, we develop a stochastic theory for intermittent search behaviours, which are often observed: the searcher alternates phases of intensive search and slow motion with fast displacements. The first results of this theory have already been announced recently. Here we provide a detailed presentation of the theory, as well as the full derivation of the results. Furthermore, we explicitly discuss the minimization of the time needed to find the target

  12. Numerical Validation of a Vortex Model against ExperimentalData on a Straight-Bladed Vertical Axis Wind Turbine

    Directory of Open Access Journals (Sweden)

    Eduard Dyachuk

    2015-10-01

    Full Text Available Cyclic blade motion during operation of vertical axis wind turbines (VAWTs imposes challenges on the simulations models of the aerodynamics of VAWTs. A two-dimensional vortex model is validated against the new experimental data on a 12-kW straight-bladed VAWT, which is operated at an open site. The results on the normal force on one blade are analyzed. The model is assessed against the measured data in the wide range of tip speed ratios: from 1.8 to 4.6. The predicted results within one revolution have a similar shape and magnitude as the measured data, though the model does not reproduce every detail of the experimental data. The present model can be used when dimensioning the turbine for maximum loads.

  13. Technology Marketing using PCA , SOM, and STP Strategy Modeling

    OpenAIRE

    Sunghae Jun

    2011-01-01

    Technology marketing is a total processing about identifying and meeting the technological needs of human society. Most technology results exist in intellectual properties like patents. In our research, we consider patent document as a technology. So patent data are analyzed by Principal Component Analysis (PCA) and Self Organizing Map (SOM) for STP(Segmentation, Targeting, and Positioning) strategy modeling. STP is a popular approach for developing marketing strategies. We use STP strategy m...

  14. Modelling Strategies for Functional Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Madsen, Kristoffer Hougaard

    2009-01-01

    and generalisations to higher order arrays are considered. Additionally, an application of the natural conjugate prior for supervised learning in the general linear model to efficiently incorporate prior information for supervised analysis is presented. Further extensions include methods to model nuisance effects...... in fMIR data thereby suppressing noise for both supervised and unsupervised analysis techniques....

  15. A Romanian energy system model and a nuclear reduction strategy

    DEFF Research Database (Denmark)

    Gota, Dan-Ioan; Lund, Henrik; Miclea, Liviu

    2011-01-01

    This paper presents a model of the Romanian energy system with the purpose of providing a tool for the analysis of future sustainable energy strategies. The model represents the total national energy system and is detailed to the level of hourly demand and production in order to be able to analyse...... the consequences of adding fluctuating renewable energy sources to the system. The model has been implemented into the EnergyPLAN tool and has been validated in order to determine if it can be used as a reference model for other simulations. In EnergyPLAN, two different future strategy scenarios for the Romanian...... energy system are compared to the actual data of Romania of year 2008. First, a comparison is made between the 2008 model and the 2013 strategy scenario corresponding to the grid of the Romanian transmission system operator (TSO) Transelectrica. Then, a comparison is made to a second strategy scenario...

  16. Model strategy for village development in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Ladislav ROLÍNEK

    2015-03-01

    Full Text Available The model strategies discussed in this article represent different ways of possible village development in the Czech Republic. We used typologies of strategies from business strategic management for their definition. Twenty municipalities, where structured interviews were carried out with their mayors, were chosen randomly from among 100 villages where a questionnaire survey was conducted in 2012 (Faltová Leitmanová, et al., 2012. Based on the qualitative analysis of the structured interview summaries, eight model strategies were ascertained. These include integration strategy, service differentiation, spending cuts, usage of municipal property, stabilization of village population, business support, fundraising, and identification of the inhabitants with the village (village pride. The most commonly applied model strategy is integration, followed by village population stabilization.

  17. An Integrative Model of Internationalization Strategies

    DEFF Research Database (Denmark)

    Li, Xin; Gammelgaard, Jens

    2014-01-01

    – The OLI and the UIP models fail to include corporate entrepreneurship and managerial psychology in their analyses. We suggest that regulatory focus theory unifies the managerial strategic choice between position logic and opportunity logic. In addition, host country institutions affect this managerial......Purpose – This paper aims to critically review the ownership, location and internalization (OLI) model and the Uppsala internationalization process (UIP) framework. We suggest that the inclusion of concepts such as corporate entrepreneurship, host country institutions and regulatory focus...... in an integrated framework helps to explain firm internationalization. Design/methodology/approach – This paper is based on a review of the literature on the OLI and UIP models. In addition, it presents a conceptual model that encompasses corporate entrepreneurship, regulatory focus and institutions. Findings...

  18. Phytoplankton models and life history strategies | Eilertsen | African ...

    African Journals Online (AJOL)

    Phytoplankton models and life history strategies. ... Chaetoceros bloom of the growth season usually starts in mid March, initiated by C. socialis. ... in some species, inoculation events are controlled by endogenous biological clocks.

  19. Models of Hepatocellular Carcinoma and Biomarker Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Bagi, Cedo M., E-mail: cedo.bagi@pfizer.com; Andresen, Catharine J. [Global Science & Technology, PGRD, Pfizer Inc, Groton, CT 06340 (United States)

    2010-07-07

    The overwhelming need to improve preclinical models in oncology has stimulated research efforts to refine and validate robust orthotopic models that closely mimic the disease population and therefore have the potential to better predict clinical outcome with novel therapies. Sophisticated technologies including bioluminescence, contrast enhanced ultrasound imaging, positron emission tomography, computed tomography and magnetic resonance imaging have been added to existing serum- and histology-based biomarkers to assist with patient selection and the design of clinical trials. The rationale for the use of human hepatocellular carcinoma (HCC) cell lines, implementation of xenograft and orthotopic animal models and utilization of available biomarkers have been discussed, providing guidelines to facilitate preclinical research for the development of treatments for HCC patients.

  20. Image-Based Models Using Crowdsourcing Strategy

    Directory of Open Access Journals (Sweden)

    Antonia Spanò

    2016-12-01

    Full Text Available The conservation and valorization of Cultural Heritage require an extensive documentation, both in properly historic-artistic terms and regarding the physical characteristics of position, shape, color, and geometry. With the use of digital photogrammetry that make acquisition of overlapping images for 3D photo modeling and with the development of dense and accurate 3D point models, it is possible to obtain high-resolution orthoprojections of surfaces.Recent years have seen a growing interest in crowdsourcing that holds in the field of the protection and dissemination of cultural heritage, in parallel there is an increasing awareness for contributing the generation of digital models with the immense wealth of images available on the web which are useful for documentation heritage.In this way, the availability and ease the automation of SfM (Structure from Motion algorithm enables the generation of digital models of the built heritage, which can be inserted positively in crowdsourcing processes. In fact, non-expert users can handle the technology in the process of acquisition, which today is one of the fundamental points to involve the wider public to the cultural heritage protection. To present the image based models and their derivatives that can be made from a great digital resource; the current approach is useful for the little-known heritage or not easily accessible buildings as an emblematic case study that was selected. It is the Vank Cathedral in Isfahan in Iran: the availability of accurate point clouds and reliable orthophotos are very convenient since the building of the Safavid epoch (cent. XVII-XVIII completely frescoed with the internal surfaces, which the architecture and especially the architectural decoration reach their peak.The experimental part of the paper explores also some aspects of usability of the digital output from the image based modeling methods. The availability of orthophotos allows and facilitates the iconographic

  1. Model for evaluating nuclear strategies with proliferation resistance

    International Nuclear Information System (INIS)

    Shay, M.R.; Hardie, R.W.; Omberg, R.P.

    1979-03-01

    A model was developed at HEDL to specifically analyze proliferation resistant strategies. The model was not designed to predict the future, but rather to provide a method for estimating the consequences of decisions affecting proliferation resistance in a rational and plausible manner. The characteristics of the model are described

  2. Strategies to Support Students' Mathematical Modeling

    Science.gov (United States)

    Jung, Hyunyi

    2015-01-01

    An important question for mathematics teachers is this: "How can we help students learn mathematics to solve everyday problems, rather than teaching them only to memorize rules and practice mathematical procedures?" Teaching students using modeling activities can help them learn mathematics in real-world problem-solving situations that…

  3. Regional Scale Modelling for Exploring Energy Strategies for Africa

    International Nuclear Information System (INIS)

    Welsch, M.

    2015-01-01

    KTH Royal Institute of Technology was founded in 1827 and it is the largest technical university in Sweden with five campuses and Around 15,000 students. KTH-dESA combines an outstanding knowledge in the field of energy systems analysis. This is demonstrated by the successful collaborations with many (UN) organizations. Regional Scale Modelling for Exploring Energy Strategies for Africa include Assessing renewable energy potentials; Analysing investment strategies; ) Assessing climate resilience; Comparing electrification options; Providing web-based decision support; and Quantifying energy access. It is conclude that Strategies required to ensure a robust and flexible energy system (-> no-regret choices); Capacity investments should be in line with national & regional strategies; Climate change important to consider, as it may strongly influence the energy flows in a region; Long-term models can help identify robust energy investment strategies and pathways that Can help assess future markets and profitability of individual projects

  4. Implementation strategies for collaborative primary care-mental health models.

    Science.gov (United States)

    Franx, Gerdien; Dixon, Lisa; Wensing, Michel; Pincus, Harold

    2013-09-01

    Extensive research exists that collaborative primary care-mental health models can improve care and outcomes for patients. These programs are currently being implemented throughout the United States and beyond. The purpose of this study is to review the literature and to generate an overview of strategies currently used to implement such models in daily practice. Six overlapping strategies to implement collaborative primary care-mental health models were described in 18 selected studies. We identified interactive educational strategies, quality improvement change processes, technological support tools, stakeholder engagement in the design and execution of implementation plans, organizational changes in terms of expanding the task of nurses and financial strategies such as additional collaboration fees and pay for performance incentives. Considering the overwhelming evidence about the effectiveness of primary care-mental health models, there is a lack of good studies focusing on their implementation strategies. In practice, these strategies are multifaceted and locally defined, as a result of intensive and required stakeholder engagement. Although many barriers still exist, the implementation of collaborative models could have a chance to succeed in the United States, where new service delivery and payment models, such as the Patient-Centered Medical Home, the Health Home and the Accountable Care Organization, are being promoted.

  5. IOOS modeling subsystem: vision and implementation strategy

    Science.gov (United States)

    Rosenfeld, Leslie; Chao, Yi; Signell, Richard P.

    2012-01-01

    Numerical modeling is vital to achieving the U.S. IOOS® goals of predicting, understanding and adapting to change in the ocean and Great Lakes. In the next decade IOOS should cultivate a holistic approach to coastal ocean prediction, and encourage more balanced investment among the observing, modeling and information management subsystems. We believe the vision of a prediction framework driven by observations, and leveraging advanced technology and understanding of the ocean and Great Lakes, would lead to a new era for IOOS that would not only produce more powerful information, but would also capture broad community support, particularly from the general public, thus allowing IOOS to develop into the comprehensive information system that was envisioned at the outset.

  6. Strategy renewal through business model innovation

    DEFF Research Database (Denmark)

    Holm, Anna; Ulhøi, John Parm

    2011-01-01

    by leading newspapers. More specifically, we review how changes introduced during the on-going development of digital platforms have affected the dominant business model and its key components at the leading newspaper industry players in Denmark, and whether those changes have improved their situation......The newspaper industry is presently under pressure in at least two important ways. First, their previous business models, based on paper-based newspapers, subscription fees and sales of advertising space are threatened by new internet-based technologies. Second, the hitherto monopoly held...... by the traditional profession behind the production of news – the journalists – is challenged by the emergence of new social movements providing fast and free news, often available directly in the making. This paper discusses the emergence of online publication of news and associated innovation activities undertaken...

  7. Investigating Habits: Strategies, Technologies, and Models

    Directory of Open Access Journals (Sweden)

    Kyle Stephen Smith

    2014-02-01

    Full Text Available Understanding habits at a biological level requires a combination of behavioral observations and measures of ongoing neural activity. Theoretical frameworks as well as definitions of habitual behaviors emerging from classic behavioral research have been enriched by new approaches taking account of the identification of brain regions and circuits related to habitual behavior. Together, this combination of experimental and theoretical work has provided key insights into how brain circuits underlying action-learning and action-selection are organized, and how a balance between behavioral flexibility and fixity is achieved. New methods to monitor and manipulate neural activity in real time are allowing us to have a first look ‘under the hood’ of a habit as it is formed and expressed. Here we discuss ideas emerging from such approaches. We pay special attention to the unexpected findings that have arisen from our own experiments suggesting that habitual behaviors likely require the simultaneous activity of multiple distinct components, or operators, seen as responsible for the contrasting dynamics of neural activity in both cortico-limbic and sensorimotor circuits recorded concurrently during different stages of habit learning. The neural dynamics identified thus far do not fully meet expectations derived from traditional models of the structure of habits, and the behavioral measures of habits that we have made also are not fully aligned with these models. We explore these new clues as opportunities to refine an understanding of habits.

  8. Product design and business model strategies for a circular economy

    NARCIS (Netherlands)

    Bocken, N.M.P.; de Pauw, I.C.; Bakker, C.A.; van der Grinten, B.

    The transition within business from a linear to a circular economy brings with it a range of practical challenges for companies. The following question is addressed: What are the product design and business model strategies for
    companies that want to move to a circular economy model? This paper

  9. A model of plant strategies in fluvial hydrosystems

    NARCIS (Netherlands)

    Bornette, G.; Tabacchi, E.; Hupp, C.; Puijalon, S.; Rostan, J.C.

    2008-01-01

    1. We propose a model of plant strategies in temperate fluvial hydrosystems that considers the hydraulic and geomorphic features that control plant recruitment, establishment and growth in river floodplains. 2. The model describes first how the disturbance gradient and the grain-size of the river

  10. An analytical model for the assessment of airline expansion strategies

    Directory of Open Access Journals (Sweden)

    Mauricio Emboaba Moreira

    2014-01-01

    Full Text Available Purpose: The purpose of this article is to develop an analytical model to assess airline expansion strategies by combining generic business strategy models with airline business models. Methodology and approach: A number of airline business models are examined, as are Porter’s (1983 industry five forces that drive competition, complemented by Nalebuff/ Brandenburger’s  (1996 sixth force, and the basic elements of the general environment in which the expansion process takes place.  A system of points and weights is developed to create a score among the 904,736 possible combinations considered. The model’s outputs are generic expansion strategies with quantitative assessments for each specific combination of elements inputted. Originality and value: The analytical model developed is original because it combines for the first time and explicitly elements of the general environment, industry environment, airline business models and the generic expansion strategy types. Besides it creates a system of scores that may be used to drive the decision process toward the choice of a specific strategic expansion path. Research implications: The analytical model may be adapted to other industries apart from the airline industry by substituting the element “airline business model” by other industries corresponding elements related to the different specific business models.

  11. Selection Strategies for Social Influence in the Threshold Model

    Science.gov (United States)

    Karampourniotis, Panagiotis; Szymanski, Boleslaw; Korniss, Gyorgy

    The ubiquity of online social networks makes the study of social influence extremely significant for its applications to marketing, politics and security. Maximizing the spread of influence by strategically selecting nodes as initiators of a new opinion or trend is a challenging problem. We study the performance of various strategies for selection of large fractions of initiators on a classical social influence model, the Threshold model (TM). Under the TM, a node adopts a new opinion only when the fraction of its first neighbors possessing that opinion exceeds a pre-assigned threshold. The strategies we study are of two kinds: strategies based solely on the initial network structure (Degree-rank, Dominating Sets, PageRank etc.) and strategies that take into account the change of the states of the nodes during the evolution of the cascade, e.g. the greedy algorithm. We find that the performance of these strategies depends largely on both the network structure properties, e.g. the assortativity, and the distribution of the thresholds assigned to the nodes. We conclude that the optimal strategy needs to combine the network specifics and the model specific parameters to identify the most influential spreaders. Supported in part by ARL NS-CTA, ARO, and ONR.

  12. PERUMUSAN STRATEGI PEMASARAN FRY COUNTER DENGAN PENDEKATAN MODEL AIDA

    OpenAIRE

    Andi Oktoriyana; Ujang Sumarwan; Hartoyo Hartoyo

    2014-01-01

    This research examined factors which are mentioned in various literatures that have influence on AIDA models to buy fry counter which are attention, interest, and desire. The model also influenced by perceived attributes, personal characteristics, and external factors. Furthermore, the analysis result become a basic for formulating the marketing strategy of fry counter as an innovative product. Analysis was carried out using Structural Equation Modeling. The data for this study were collected...

  13. Strategy Guideline: Modeling Enclosure Design in Above-Grade Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, J. [Building Science Corporation, Westford, MA (United States); Ueno, K. [Building Science Corporation, Westford, MA (United States); Musunuru, S. [Building Science Corporation, Westford, MA (United States)

    2016-02-24

    The Strategy Guideline describes how to model and interpret results of models for above grade walls. The Measure Guideline analyzes the failure thresholds and criteria for above grade walls. A library of above-grade walls with historically successful performance was used to calibrate WUFI (Warme Und Feuchte Instationar) software models. The information is generalized for application to a broad population of houses within the limits of existing experience.

  14. Business models for open innovation: Matching heterogeneous open innovation strategies with business model dimensions

    OpenAIRE

    Saebi, Tina; Foss, Nicolai Juul

    2015-01-01

    -This is the author's version of the article:"Business models for open innovation: Matching heterogeneous open innovation strategies with business model dimensions", European Management Journal, Volume 33, Issue 3, June 2015, Pages 201–213 Research on open innovation suggests that companies benefit differentially from adopting open innovation strategies; however, it is unclear why this is so. One possible explanation is that companies' business models are not attuned to open strategies. Ac...

  15. Validation of an Actuator Line Model Coupled to a Dynamic Stall Model for Pitching Motions Characteristic to Vertical Axis Turbines

    International Nuclear Information System (INIS)

    Mendoza, Victor; Goude, Anders; Bachant, Peter; Wosnik, Martin

    2016-01-01

    Vertical axis wind turbines (VAWT) can be used to extract renewable energy from wind flows. A simpler design, low cost of maintenance, and the ability to accept flow from all directions perpendicular to the rotor axis are some of the most important advantages over conventional horizontal axis wind turbines (HAWT). However, VAWT encounter complex and unsteady fluid dynamics, which present significant modeling challenges. One of the most relevant phenomena is dynamic stall, which is caused by the unsteady variation of angle of attack throughout the blade rotation, and is the focus of the present study. Dynamic stall is usually used as a passive control for VAWT operating conditions, hence the importance of predicting its effects. In this study, a coupled model is implemented with the open-source CFD toolbox OpenFOAM for solving the Navier-Stokes equations, where an actuator line model and dynamic stall model are used to compute the blade loading and body force. Force coefficients obtained from the model are validated with experimental data of pitching airfoil in similar operating conditions as an H-rotor type VAWT. Numerical results show reasonable agreement with experimental data for pitching motion. (paper)

  16. Validation of an Actuator Line Model Coupled to a Dynamic Stall Model for Pitching Motions Characteristic to Vertical Axis Turbines

    Science.gov (United States)

    Mendoza, Victor; Bachant, Peter; Wosnik, Martin; Goude, Anders

    2016-09-01

    Vertical axis wind turbines (VAWT) can be used to extract renewable energy from wind flows. A simpler design, low cost of maintenance, and the ability to accept flow from all directions perpendicular to the rotor axis are some of the most important advantages over conventional horizontal axis wind turbines (HAWT). However, VAWT encounter complex and unsteady fluid dynamics, which present significant modeling challenges. One of the most relevant phenomena is dynamic stall, which is caused by the unsteady variation of angle of attack throughout the blade rotation, and is the focus of the present study. Dynamic stall is usually used as a passive control for VAWT operating conditions, hence the importance of predicting its effects. In this study, a coupled model is implemented with the open-source CFD toolbox OpenFOAM for solving the Navier-Stokes equations, where an actuator line model and dynamic stall model are used to compute the blade loading and body force. Force coefficients obtained from the model are validated with experimental data of pitching airfoil in similar operating conditions as an H-rotor type VAWT. Numerical results show reasonable agreement with experimental data for pitching motion.

  17. Structures and scan strategies of software net models

    International Nuclear Information System (INIS)

    Puhr-Westerheide, P.; Sandbaek, H.

    1984-01-01

    The present paper deals with some aspects of plant control and monitoring systems as used in nuclear power plants. These aspects concern executable net models to run on computers. A short survey on the nets' environment and on some net scan strategies is given. Among the strategies are the 'topologically ordered scan' and the 'signal propagation scan'. A combined method 'topologically ordered signal propagation (TOSIP) scan' will be outlined as well as a net model data structure that allows the definition of subsystems for the use of clear structuration and dischargement to distributed systems. (author)

  18. Control strategies and sensitivity analysis of anthroponotic visceral leishmaniasis model.

    Science.gov (United States)

    Zamir, Muhammad; Zaman, Gul; Alshomrani, Ali Saleh

    2017-12-01

    This study proposes a mathematical model of Anthroponotic visceral leishmaniasis epidemic with saturated infection rate and recommends different control strategies to manage the spread of this disease in the community. To do this, first, a model formulation is presented to support these strategies, with quantifications of transmission and intervention parameters. To understand the nature of the initial transmission of the disease, the reproduction number [Formula: see text] is obtained by using the next-generation method. On the basis of sensitivity analysis of the reproduction number [Formula: see text], four different control strategies are proposed for managing disease transmission. For quantification of the prevalence period of the disease, a numerical simulation for each strategy is performed and a detailed summary is presented. Disease-free state is obtained with the help of control strategies. The threshold condition for globally asymptotic stability of the disease-free state is found, and it is ascertained that the state is globally stable. On the basis of sensitivity analysis of the reproduction number, it is shown that the disease can be eradicated by using the proposed strategies.

  19. Identifying optimal agricultural countermeasure strategies for a hypothetical contamination scenario using the strategy model

    International Nuclear Information System (INIS)

    Cox, G.; Beresford, N.A.; Alvarez-Farizo, B.; Oughton, D.; Kis, Z.; Eged, K.; Thorring, H.; Hunt, J.; Wright, S.; Barnett, C.L.; Gil, J.M.; Howard, B.J.; Crout, N.M.J.

    2005-01-01

    A spatially implemented model designed to assist the identification of optimal countermeasure strategies for radioactively contaminated regions is described. Collective and individual ingestion doses for people within the affected area are estimated together with collective exported ingestion dose. A range of countermeasures are incorporated within the model, and environmental restrictions have been included as appropriate. The model evaluates the effectiveness of a given combination of countermeasures through a cost function which balances the benefit obtained through the reduction in dose with the cost of implementation. The optimal countermeasure strategy is the combination of individual countermeasures (and when and where they are implemented) which gives the lowest value of the cost function. The model outputs should not be considered as definitive solutions, rather as interactive inputs to the decision making process. As a demonstration the model has been applied to a hypothetical scenario in Cumbria (UK). This scenario considered a published nuclear power plant accident scenario with a total deposition of 1.7 x 10 14 , 1.2 x 10 13 , 2.8 x 10 10 and 5.3 x 10 9 Bq for Cs-137, Sr-90, Pu-239/240 and Am-241, respectively. The model predicts that if no remediation measures were implemented the resulting collective dose would be approximately 36 000 person-Sv (predominantly from 137 Cs) over a 10-year period post-deposition. The optimal countermeasure strategy is predicted to avert approximately 33 000 person-Sv at a cost of approximately pound 160 million. The optimal strategy comprises a mixture of ploughing, AFCF (ammonium-ferric hexacyano-ferrate) administration, potassium fertiliser application, clean feeding of livestock and food restrictions. The model recommends specific areas within the contaminated area and time periods where these measures should be implemented

  20. An Integrative Model of Dynamic Strategy-Making

    DEFF Research Database (Denmark)

    Andersen, Torben Juul; Hallin, Carina Antonia; Li, Xin

    . We adopt the frame of complementary Yin-Yang elements and Zhong Yong balance to explain the time bound interaction between these opposing yet complementary strategy-making mechanisms where tradeoffs and synergies are balanced across hierarchical levels. The model outlines how the interaction between......The organizational capacity to cope with unexpected changes remains a fundamental challenge in strategy as global competition and technological innovation increase environmental uncertainty. Whereas conventional strategy-making often is conceived as a sequential linear process, we see it as a non......-linear interaction between top-down and bottom-up mechanisms dealing with multiple actions taken throughout the organization over time. It is driven by intension but with a flexible balance between centralized (planned) and decentralized (spontaneous) activities where strategy formulation and implementation interact...

  1. An optimization strategy for a biokinetic model of inhaled radionuclides

    International Nuclear Information System (INIS)

    Shyr, L.J.; Griffith, W.C.; Boecker, B.B.

    1991-01-01

    Models for material disposition and dosimetry involve predictions of the biokinetics of the material among compartments representing organs and tissues in the body. Because of a lack of human data for most toxicants, many of the basic data are derived by modeling the results obtained from studies using laboratory animals. Such a biomathematical model is usually developed by adjusting the model parameters to make the model predictions match the measured retention and excretion data visually. The fitting process can be very time-consuming for a complicated model, and visual model selections may be subjective and easily biased by the scale or the data used. Due to the development of computerized optimization methods, manual fitting could benefit from an automated process. However, for a complicated model, an automated process without an optimization strategy will not be efficient, and may not produce fruitful results. In this paper, procedures for, and implementation of, an optimization strategy for a complicated mathematical model is demonstrated by optimizing a biokinetic model for 144Ce in fused aluminosilicate particles inhaled by beagle dogs. The optimized results using SimuSolv were compared to manual fitting results obtained previously using the model simulation software GASP. Also, statistical criteria provided by SimuSolv, such as likelihood function values, were used to help or verify visual model selections

  2. A strategy to establish Food Safety Model Repositories.

    Science.gov (United States)

    Plaza-Rodríguez, C; Thoens, C; Falenski, A; Weiser, A A; Appel, B; Kaesbohrer, A; Filter, M

    2015-07-02

    Transferring the knowledge of predictive microbiology into real world food manufacturing applications is still a major challenge for the whole food safety modelling community. To facilitate this process, a strategy for creating open, community driven and web-based predictive microbial model repositories is proposed. These collaborative model resources could significantly improve the transfer of knowledge from research into commercial and governmental applications and also increase efficiency, transparency and usability of predictive models. To demonstrate the feasibility, predictive models of Salmonella in beef previously published in the scientific literature were re-implemented using an open source software tool called PMM-Lab. The models were made publicly available in a Food Safety Model Repository within the OpenML for Predictive Modelling in Food community project. Three different approaches were used to create new models in the model repositories: (1) all information relevant for model re-implementation is available in a scientific publication, (2) model parameters can be imported from tabular parameter collections and (3) models have to be generated from experimental data or primary model parameters. All three approaches were demonstrated in the paper. The sample Food Safety Model Repository is available via: http://sourceforge.net/projects/microbialmodelingexchange/files/models and the PMM-Lab software can be downloaded from http://sourceforge.net/projects/pmmlab/. This work also illustrates that a standardized information exchange format for predictive microbial models, as the key component of this strategy, could be established by adoption of resources from the Systems Biology domain. Copyright © 2015. Published by Elsevier B.V.

  3. Adaptive Active Noise Suppression Using Multiple Model Switching Strategy

    Directory of Open Access Journals (Sweden)

    Quanzhen Huang

    2017-01-01

    Full Text Available Active noise suppression for applications where the system response varies with time is a difficult problem. The computation burden for the existing control algorithms with online identification is heavy and easy to cause control system instability. A new active noise control algorithm is proposed in this paper by employing multiple model switching strategy for secondary path varying. The computation is significantly reduced. Firstly, a noise control system modeling method is proposed for duct-like applications. Then a multiple model adaptive control algorithm is proposed with a new multiple model switching strategy based on filter-u least mean square (FULMS algorithm. Finally, the proposed algorithm was implemented on Texas Instruments digital signal processor (DSP TMS320F28335 and real time experiments were done to test the proposed algorithm and FULMS algorithm with online identification. Experimental verification tests show that the proposed algorithm is effective with good noise suppression performance.

  4. Between architecture and model: Strategies for cognitive control

    NARCIS (Netherlands)

    Taatgen, Niels

    One major limitation of current cognitive architectures is that models are typically constructed in an “empty” architecture, and that the knowledge specifications (typically production rules) are specific to the particular task. This means that general cognitive control strategies have to be

  5. Thermo-Chemical Modelling Strategies for the Pultrusion Process

    DEFF Research Database (Denmark)

    Baran, Ismet; Hattel, Jesper Henri; Tutum, Cem Celal

    2013-01-01

    In the present study, three dimensional (3D) numerical modeling strategies of a thermosetting pultrusion process are investigated considering both transient and steady state approaches. For the transient solution, an unconditionally stable alternating direction implicit Douglas-Gunn (ADI-DG) sche...

  6. Design and modeling of reservoir operation strategies for sediment management

    NARCIS (Netherlands)

    Sloff, C.J.; Omer, A.Y.A.; Heynert, K.V.; Mohamed, Y.A.

    2015-01-01

    Appropriate operation strategies that allow for sediment flushing and sluicing (sediment routing) can reduce rapid storage losses of (hydropower and water-supply) reservoirs. In this study we have shown, using field observations and computational models, that the efficiency of these operations

  7. Classified model and characteristics of strategies at tourist companies

    Directory of Open Access Journals (Sweden)

    I.V. Saukh

    2017-12-01

    Full Text Available The research is devoted to the assessment of the scientific approaches to the identification of classification features of the strategy and its types distinguished in accordance with the mentioned features. The research object is the activities of tourist companies and this determines the choice of strategies typical for the tourism field. It is substantiated that the scientific approaches to the classification of strategies are various in specific literature because of obscurity in the strategy definition, vagueness and plurality of its classified features. Due to the current research the authors have improved the classified model of strategies for tourist companies that will result in making effective management decisions directed to the development of enterprise potential under conditions of unstable and unpredictable external environment. The paper singles out the peculiarities of functioning the tourism branch, which are the following : high sensitivity to the changes in external environment; the high level of competition in the field; dynamics and the lack of necessity for the use of «far-seeing» strategies; insufficiency of information provision for the application of traditional western models and matric methods of strategy development; time gap between obtaining the service and its consumption; a great number of intermediaries; seasonal swings in demands; the sudden shift of external environment caused by cyclicity, globalization, political decisions of separate countries and etc. The article shows essential differences in the development of financial strategies of small-scale enterprises and stock companies of tourist business. It is substantiated that small-scale enterprises develop strategies directed to a higher level of personal services, occupational competence, ability and experience in designing, the best knowledge of regional conditions and flexible decisions caused by the peculiarities of the received orders. Taking into

  8. Modelling Difficulties and Their Overcoming Strategies in the Solution of a Modelling Problem

    Science.gov (United States)

    Dede, Ayse Tekin

    2016-01-01

    The purpose of the study is to reveal the elementary mathematics student teachers' difficulties encountered in the solution of a modelling problem, the strategies to overcome those difficulties and whether the strategies worked or not. Nineteen student teachers solved the modelling problem in their four or five-person groups, and the video records…

  9. A multiple relevance feedback strategy with positive and negative models.

    Directory of Open Access Journals (Sweden)

    Yunlong Ma

    Full Text Available A commonly used strategy to improve search accuracy is through feedback techniques. Most existing work on feedback relies on positive information, and has been extensively studied in information retrieval. However, when a query topic is difficult and the results from the first-pass retrieval are very poor, it is impossible to extract enough useful terms from a few positive documents. Therefore, the positive feedback strategy is incapable to improve retrieval in this situation. Contrarily, there is a relatively large number of negative documents in the top of the result list, and it has been confirmed that negative feedback strategy is an important and useful way for adapting this scenario by several recent studies. In this paper, we consider a scenario when the search results are so poor that there are at most three relevant documents in the top twenty documents. Then, we conduct a novel study of multiple strategies for relevance feedback using both positive and negative examples from the first-pass retrieval to improve retrieval accuracy for such difficult queries. Experimental results on these TREC collections show that the proposed language model based multiple model feedback method which is generally more effective than both the baseline method and the methods using only positive or negative model.

  10. Sensor-Based Model Driven Control Strategy for Precision Irrigation

    Directory of Open Access Journals (Sweden)

    Camilo Lozoya

    2016-01-01

    Full Text Available Improving the efficiency of the agricultural irrigation systems substantially contributes to sustainable water management. This improvement can be achieved through an automated irrigation system that includes a real-time control strategy based on the water, soil, and crop relationship. This paper presents a model driven control strategy applied to an irrigation system, in order to make an efficient use of water for large crop fields, that is, applying the correct amount of water in the correct place at the right moment. The proposed model uses a predictive algorithm that senses soil moisture and weather variables, to determine optimal amount of water required by the crop. This proposed approach is evaluated against a traditional irrigation system based on the empirical definition of time periods and against a basic soil moisture control system. Results indicate that the use of a model predictive control in an irrigation system achieves a higher efficiency and significantly reduce the water consumption.

  11. MODEL OF SUCCESSFUL STRATEGY EXECUTION: REVISING THE CONCEPT

    Directory of Open Access Journals (Sweden)

    Joanna Radomska

    2014-12-01

    Full Text Available The purpose of this research is to examine the relationship between the elements of the Eight "S" model that affect strategic implementation and results achieved by companies. The main research question, to which the author sought an answer, was whether there was a relationship between individual elements that affect strategy implementation and the effects it brings in revenue growth. The survey covered 200 of the best-ranked Polish companies (where revenues constituted one of the ranking criteria where the level of strategic implementation was considered satisfactory. Testing of the research hypotheses has shown that the factors defined as Resources and Shared Values have a minor impact on the strategy implementation. The research also has shown that there is an additional element that could be incorporated into the model - the system of informal communication. In addition, the paper describes the interrelations between elements of the model.

  12. A strategy learning model for autonomous agents based on classification

    Directory of Open Access Journals (Sweden)

    Śnieżyński Bartłomiej

    2015-09-01

    Full Text Available In this paper we propose a strategy learning model for autonomous agents based on classification. In the literature, the most commonly used learning method in agent-based systems is reinforcement learning. In our opinion, classification can be considered a good alternative. This type of supervised learning can be used to generate a classifier that allows the agent to choose an appropriate action for execution. Experimental results show that this model can be successfully applied for strategy generation even if rewards are delayed. We compare the efficiency of the proposed model and reinforcement learning using the farmer-pest domain and configurations of various complexity. In complex environments, supervised learning can improve the performance of agents much faster that reinforcement learning. If an appropriate knowledge representation is used, the learned knowledge may be analyzed by humans, which allows tracking the learning process

  13. Regression Models for Predicting Force Coefficients of Aerofoils

    Directory of Open Access Journals (Sweden)

    Mohammed ABDUL AKBAR

    2015-09-01

    Full Text Available Renewable sources of energy are attractive and advantageous in a lot of different ways. Among the renewable energy sources, wind energy is the fastest growing type. Among wind energy converters, Vertical axis wind turbines (VAWTs have received renewed interest in the past decade due to some of the advantages they possess over their horizontal axis counterparts. VAWTs have evolved into complex 3-D shapes. A key component in predicting the output of VAWTs through analytical studies is obtaining the values of lift and drag coefficients which is a function of shape of the aerofoil, ‘angle of attack’ of wind and Reynolds’s number of flow. Sandia National Laboratories have carried out extensive experiments on aerofoils for the Reynolds number in the range of those experienced by VAWTs. The volume of experimental data thus obtained is huge. The current paper discusses three Regression analysis models developed wherein lift and drag coefficients can be found out using simple formula without having to deal with the bulk of the data. Drag coefficients and Lift coefficients were being successfully estimated by regression models with R2 values as high as 0.98.

  14. Strategy Guideline. Modeling Enclosure Design in Above-Grade Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, J. [Building Science Corporation, Westford, MA (United States); Ueno, K. [Building Science Corporation, Westford, MA (United States); Musunuru, S. [Building Science Corporation, Westford, MA (United States)

    2016-02-01

    The Strategy Guideline, written by the U.S. Department of Energy's research team Building Science Corporation, 1) describes how to model and interpret results of models for above-grade walls, and 2) analyzes the failure thresholds and criteria for above-grade walls. A library of above-grade walls with historically successful performance was used to calibrate WUFI (Wärme und Feuchte instationär) software models. The information is generalized for application to a broad population of houses within the limits of existing experience.

  15. EFEKTIVITAS STRATEGI PENGELOMPOKAN BERPASANGAN DALAM PEMBELAJARAN MATEMATIKA MODEL CORE

    Directory of Open Access Journals (Sweden)

    Endah Retnowati

    2017-02-01

    Full Text Available Abstrak: Penelitian ini bertujuan untuk menguji keefektifan pembelajaran CORE (Connect, Organize, Reflect, Extend pada pembelajaran geometri transformasi dengan strategi pengelompokan yang berbeda ditinjau dari kemampuan penalaran, prestasi, dan self efficacy. Penelitian ini merupakan penelitian eksperimen semu dengan populasi siswa kelas XI IPA SMA yang baru pertama kali mempelajari materi geometri transformasi. Sampel penelitian sebanyak dua kelas masing-masing terdiri atas 40 siswa. Siswa belajar dengan dikelompokkan secara berpasangan atau kelompok kecil. Data dikumpulkan dengan teknik tes dan nontes serta dianalisis dengan teknik statistik deskriptif dan inferensial (Manova. Hasil penelitian menunjukkan bahwa pembelajaran CORE strategi berpasangan maupun kelompok kecil efektif ditinjau dari Kriteria Ketuntasan Minimum kemampuan penalaran, prestasi dan self efficacy yang ditetapkan, tetapi tidak terdapat perbedaan yang signifikan di antara kedua strategi pengelompokan tersebut. Repeated measures analysis of variance menunjukkan bahwa kompleksitas materi pembelajaran memengaruhi prestasi belajar secara signifikan. Semakin kompleks materi pembelajaran, penggunaan strategi kelompok kecil lebih baik daripada berpasangan. Kata kunci: CORE, kemampuan penalaran, prestasi belajar, self efficacy THE EFFECTIVENESS OF DYAD STRATEGY DURING MATHEMATICS LEARNING BASED ON CORE MODEL Abstract: The purpose of this study is to test the effectiveness of an instruction, namely CORE (Connect, Organize, Reflect, Extend model, for learning geometry transformation in different grouping strategies (by dyads and small-group work, in terms of reasoning ability, achievement, and self-efficacy. This study was a quasi-experimental research with the entire population of science 11th graders who were novices in geometry transformation. The research samples were two classes which respectively consist of 40 students. Students learned all material either in dyads or small

  16. Model building strategy for logistic regression: purposeful selection.

    Science.gov (United States)

    Zhang, Zhongheng

    2016-03-01

    Logistic regression is one of the most commonly used models to account for confounders in medical literature. The article introduces how to perform purposeful selection model building strategy with R. I stress on the use of likelihood ratio test to see whether deleting a variable will have significant impact on model fit. A deleted variable should also be checked for whether it is an important adjustment of remaining covariates. Interaction should be checked to disentangle complex relationship between covariates and their synergistic effect on response variable. Model should be checked for the goodness-of-fit (GOF). In other words, how the fitted model reflects the real data. Hosmer-Lemeshow GOF test is the most widely used for logistic regression model.

  17. A modeling strategy for G-protein coupled receptors

    Directory of Open Access Journals (Sweden)

    Anna Kahler

    2016-03-01

    Full Text Available Cell responses can be triggered via G-protein coupled receptors (GPCRs that interact with small molecules, peptides or proteins and transmit the signal over the membrane via structural changes to activate intracellular pathways. GPCRs are characterized by a rather low sequence similarity and exhibit structural differences even for functionally closely related GPCRs. An accurate structure prediction for GPCRs is therefore not straightforward. We propose a computational approach that relies on the generation of several independent models based on different template structures, which are subsequently refined by molecular dynamics simulations. A comparison of their conformational stability and the agreement with GPCR-typical structural features is then used to select a favorable model. This strategy was applied to predict the structure of the herpesviral chemokine receptor US28 by generating three independent models based on the known structures of the chemokine receptors CXCR1, CXCR4, and CCR5. Model refinement and evaluation suggested that the model based on CCR5 exhibits the most favorable structural properties. In particular, the GPCR-typical structural features, such as a conserved water cluster or conserved non-covalent contacts, are present to a larger extent in the model based on CCR5 compared to the other models. A final model validation based on the recently published US28 crystal structure confirms that the CCR5-based model is the most accurate and exhibits 80.8% correctly modeled residues within the transmembrane helices. The structural agreement between the selected model and the crystal structure suggests that our modeling strategy may also be more generally applicable to other GPCRs of unknown structure.

  18. Cyanobacterial Biofuels: Strategies and Developments on Network and Modeling.

    Science.gov (United States)

    Klanchui, Amornpan; Raethong, Nachon; Prommeenate, Peerada; Vongsangnak, Wanwipa; Meechai, Asawin

    Cyanobacteria, the phototrophic microorganisms, have attracted much attention recently as a promising source for environmentally sustainable biofuels production. However, barriers for commercial markets of cyanobacteria-based biofuels concern the economic feasibility. Miscellaneous strategies for improving the production performance of cyanobacteria have thus been developed. Among these, the simple ad hoc strategies resulting in failure to optimize fully cell growth coupled with desired product yield are explored. With the advancement of genomics and systems biology, a new paradigm toward systems metabolic engineering has been recognized. In particular, a genome-scale metabolic network reconstruction and modeling is a crucial systems-based tool for whole-cell-wide investigation and prediction. In this review, the cyanobacterial genome-scale metabolic models, which offer a system-level understanding of cyanobacterial metabolism, are described. The main process of metabolic network reconstruction and modeling of cyanobacteria are summarized. Strategies and developments on genome-scale network and modeling through the systems metabolic engineering approach are advanced and employed for efficient cyanobacterial-based biofuels production.

  19. On the renewal risk model under a threshold strategy

    Science.gov (United States)

    Dong, Yinghui; Wang, Guojing; Yuen, Kam C.

    2009-08-01

    In this paper, we consider the renewal risk process under a threshold dividend payment strategy. For this model, the expected discounted dividend payments and the Gerber-Shiu expected discounted penalty function are investigated. Integral equations, integro-differential equations and some closed form expressions for them are derived. When the claims are exponentially distributed, it is verified that the expected penalty of the deficit at ruin is proportional to the ruin probability.

  20. Site investigations: Strategy for rock mechanics site descriptive model

    International Nuclear Information System (INIS)

    Andersson, Johan; Christiansson, Rolf; Hudson, John

    2002-05-01

    As a part of the planning work for the Site Investigations, SKB has developed a Rock Mechanics Site Descriptive Modelling Strategy. Similar strategies are being developed for other disciplines. The objective of the strategy is that it should guide the practical implementation of evaluating site specific data during the Site Investigations. It is also understood that further development may be needed. This methodology enables the crystalline rock mass to be characterised in terms of the quality at different sites, for considering rock engineering constructability, and for providing the input to numerical models and performance assessment calculations. The model describes the initial stresses and the distribution of deformation and strength properties of the intact rock, of fractures and fracture zones, and of the rock mass. The rock mass mechanical properties are estimated by empirical relations and by numerical simulations. The methodology is based on estimation of mechanical properties using both empirical and heroretical/numerical approaches; and estimation of in situ rock stress using judgement and numerical modelling, including the influence of fracture zones. These approaches are initially used separately, and then combined to produce the required characterisation estimates. The methodology was evaluated with a Test Case at the Aespoe Hard Rock Laboratory in Sweden. The quality control aspects are an important feature of the methodology: these include Protocols to ensure the structure and coherence of the procedures used, regular meetings to enhance communication, feedback from internal and external reviewing, plus the recording of an audit trail of the development steps and decisions made. The strategy will be reviewed and, if required, updated as appropriate

  1. Site investigations: Strategy for rock mechanics site descriptive model

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Johan [JA Streamflow AB, Aelvsjoe (Sweden); Christiansson, Rolf [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Hudson, John [Rock Engineering Consultants, Welwyn Garden City (United Kingdom)

    2002-05-01

    As a part of the planning work for the Site Investigations, SKB has developed a Rock Mechanics Site Descriptive Modelling Strategy. Similar strategies are being developed for other disciplines. The objective of the strategy is that it should guide the practical implementation of evaluating site specific data during the Site Investigations. It is also understood that further development may be needed. This methodology enables the crystalline rock mass to be characterised in terms of the quality at different sites, for considering rock engineering constructability, and for providing the input to numerical models and performance assessment calculations. The model describes the initial stresses and the distribution of deformation and strength properties of the intact rock, of fractures and fracture zones, and of the rock mass. The rock mass mechanical properties are estimated by empirical relations and by numerical simulations. The methodology is based on estimation of mechanical properties using both empirical and heroretical/numerical approaches; and estimation of in situ rock stress using judgement and numerical modelling, including the influence of fracture zones. These approaches are initially used separately, and then combined to produce the required characterisation estimates. The methodology was evaluated with a Test Case at the Aespoe Hard Rock Laboratory in Sweden. The quality control aspects are an important feature of the methodology: these include Protocols to ensure the structure and coherence of the procedures used, regular meetings to enhance communication, feedback from internal and external reviewing, plus the recording of an audit trail of the development steps and decisions made. The strategy will be reviewed and, if required, updated as appropriate.

  2. MODEL PEMBELAJARAN DILEMA MORAL DAN KONTEMPLASI DENGAN STRATEGI KOOPERATIF

    Directory of Open Access Journals (Sweden)

    C. Asri Budiningsih

    2013-09-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui keefektifan model Pembelajaran Dilema Moral, Kontemplasi, dan Strategi Kooperatif. Penelitian tindakan kelas dilakukan di Prodi Teknologi Pendidikan FIP-UNY. Subjek penelitian 37 orang mahasiswa. Tindakan dilakukan dalam dua siklus masing-masing terdiri atas empat kali tatap muka. Data tentang proses pembelajaran, kerjasama mahasiswa, situasi yang berpengaruh terhadap upaya peningkatan kualitas pembelajaran, penalaran moral, dan keimanan mahasiswa, digali melalui pengamatan, tes penalaran moral yang diadaptasi dari Kohlberg, tes perkembangan iman yang diadaptasi dari Fowler, panduan kontemplasi, angket terbuka, dan cerita-cerita dilema moral. Analisis data dilakukan secara kuantitatif dan kualitatif. Hasil penelitian menunjukkan bahwa (1 model pembelajaran terintegrasi mampu meningkatkan penalaran moral, dan keimanan mahasiswa, sehingga tidak ada lagi penalaran moral responden yang berada pada tahap II, 24,3% meningkat dari tahap II ke tahap III, 32,43% meningkat dari tahap III ke tahap IV dan 2,7% meningkat dari tahap IV ke tahap V, 48,65% meningkat dari tahap III ke tahap IV, dan 5,4% meningkat dari tahap IV ke tahap V. Penggunaan strategi kooperatif membuat mahasiswa mampu melakukan kerjasama di dalam kelompok; 35,13% mahasiswa dalam kategori sangat baik, 56,76% dalam kategori baik, dan 8,1% dalam kategori sedang. Kata kunci       :           model pembelajaran dilema moral, kontemplasi, strategi kooperatif, penalaran moral, keimanan

  3. Evaluation of Differentiation Strategy in Shipping Enterprises with Simulation Model

    Science.gov (United States)

    Vaxevanou, Anthi Z.; Ferfeli, Maria V.; Damianos, Sakas P.

    2009-08-01

    The present inquiring study aims at investigating the circumstances that prevail in the European Shipping Enterprises with special reference to the Greek ones. This investigation is held in order to explore the potential implementation of strategies so as to create a unique competitive advantage [1]. The Shipping sector is composed of enterprises that are mainly activated in the following three areas: the passenger, the commercial and the naval. The main target is to create a dynamic simulation model which, with reference to the STAIR strategic model, will evaluate the strategic differential choice that some of the shipping enterprises have.

  4. Creating a benchmark of vertical axis wind turbines in dynamic stall for validating numerical models

    DEFF Research Database (Denmark)

    Castelein, D.; Ragni, D.; Tescione, G.

    2015-01-01

    An experimental campaign using Particle Image Velocimetry (2C-PIV) technique has been conducted on a H-type Vertical Axis Wind Turbine (VAWT) to create a benchmark for validating and comparing numerical models. The turbine is operated at tip speed ratios (TSR) of 4.5 and 2, at an average chord...

  5. An Overview of Strategy Development Models and the Ward-Rivani Model

    OpenAIRE

    David Ward; Elena Rivani

    2005-01-01

    Numerous models for developing strategy, defining and aligning competitive advantage have been proposed over the years (and even centuries if we consider Arian, Sun Tzu etc.) including probably the most famous of all, the 5 forces model by Porter (P5F). With publications in the field of strategy now in the thousands it is difficult to get an overall picture of how to classify and appreciate strategy tools and models. Mintzberg et al. have developed schools of thought to help alleviate and cat...

  6. Web malware spread modelling and optimal control strategies

    Science.gov (United States)

    Liu, Wanping; Zhong, Shouming

    2017-02-01

    The popularity of the Web improves the growth of web threats. Formulating mathematical models for accurate prediction of malicious propagation over networks is of great importance. The aim of this paper is to understand the propagation mechanisms of web malware and the impact of human intervention on the spread of malicious hyperlinks. Considering the characteristics of web malware, a new differential epidemic model which extends the traditional SIR model by adding another delitescent compartment is proposed to address the spreading behavior of malicious links over networks. The spreading threshold of the model system is calculated, and the dynamics of the model is theoretically analyzed. Moreover, the optimal control theory is employed to study malware immunization strategies, aiming to keep the total economic loss of security investment and infection loss as low as possible. The existence and uniqueness of the results concerning the optimality system are confirmed. Finally, numerical simulations show that the spread of malware links can be controlled effectively with proper control strategy of specific parameter choice.

  7. Modeling Coherent Strategies for the Sustainable Development Goals

    Science.gov (United States)

    Walsh, B.; Obersteiner, M.; Herrero, M.; Riahi, K.; Fritz, S.; van Vuuren, D.; Havlik, P.

    2016-12-01

    The Sustainable Development Goals (SDGs) call for a comprehensive new approach to development rooted in planetary boundaries, equity and inclusivity. Societies have largely responded to this call with siloed strategies capable of making progress on selected subsets of these goals. However, agendas crafted specifically to alleviate poverty, hunger, deforestation, biodiversity loss, or other ills may doom the SDG agenda, as policies and strategies designed to accomplish one or several goals can impede and in some cases reverse progress toward others at national, regional, and global levels. We adopt a comprehensive modeling approach to understand the basis for tradeoffs among environmental conservation initiatives (goals 13-15) and food prices (goal 2). We show that such tradeoffs are manifestations of policy-driven pressure in land (i.e. agricultural and environmental) systems. By reducing total land system pressure, Sustainable Consumption and Production (SCP, goal 12) policies minimize tradeoffs and should therefore be regarded as necessary conditions for achieving multiple SDGs. SDG strategies constructed around SCP policies escape problem-shifting, which has long placed global development and conservation agendas at odds. We expect that this and future systems analyses will allow policymakers to negotiate tradeoffs and exploit synergies as they assemble sustainable development strategies equal in scope to the ambition of the SDGs.

  8. Fast uncertainty reduction strategies relying on Gaussian process models

    International Nuclear Information System (INIS)

    Chevalier, Clement

    2013-01-01

    This work deals with sequential and batch-sequential evaluation strategies of real-valued functions under limited evaluation budget, using Gaussian process models. Optimal Stepwise Uncertainty Reduction (SUR) strategies are investigated for two different problems, motivated by real test cases in nuclear safety. First we consider the problem of identifying the excursion set above a given threshold T of a real-valued function f. Then we study the question of finding the set of 'safe controlled configurations', i.e. the set of controlled inputs where the function remains below T, whatever the value of some others non-controlled inputs. New SUR strategies are presented, together with efficient procedures and formulas to compute and use them in real world applications. The use of fast formulas to recalculate quickly the posterior mean or covariance function of a Gaussian process (referred to as the 'kriging update formulas') does not only provide substantial computational savings. It is also one of the key tools to derive closed form formulas enabling a practical use of computationally-intensive sampling strategies. A contribution in batch-sequential optimization (with the multi-points Expected Improvement) is also presented. (author)

  9. Models for electricity market efficiency and bidding strategy analysis

    Science.gov (United States)

    Niu, Hui

    This dissertation studies models for the analysis of market efficiency and bidding behaviors of market participants in electricity markets. Simulation models are developed to estimate how transmission and operational constraints affect the competitive benchmark and market prices based on submitted bids. This research contributes to the literature in three aspects. First, transmission and operational constraints, which have been neglected in most empirical literature, are considered in the competitive benchmark estimation model. Second, the effects of operational and transmission constraints on market prices are estimated through two models based on the submitted bids of market participants. Third, these models are applied to analyze the efficiency of the Electric Reliability Council Of Texas (ERCOT) real-time energy market by simulating its operations for the time period from January 2002 to April 2003. The characteristics and available information for the ERCOT market are considered. In electricity markets, electric firms compete through both spot market bidding and bilateral contract trading. A linear asymmetric supply function equilibrium (SFE) model with transmission constraints is proposed in this dissertation to analyze the bidding strategies with forward contracts. The research contributes to the literature in several aspects. First, we combine forward contracts, transmission constraints, and multi-period strategy (an obligation for firms to bid consistently over an extended time horizon such as a day or an hour) into the linear asymmetric supply function equilibrium framework. As an ex-ante model, it can provide qualitative insights into firms' behaviors. Second, the bidding strategies related to Transmission Congestion Rights (TCRs) are discussed by interpreting TCRs as linear combination of forwards. Third, the model is a general one in the sense that there is no limitation on the number of firms and scale of the transmission network, which can have

  10. Electric Water Heater Modeling and Control Strategies for Demand Response

    Energy Technology Data Exchange (ETDEWEB)

    Diao, Ruisheng; Lu, Shuai; Elizondo, Marcelo A.; Mayhorn, Ebony T.; Zhang, Yu; Samaan, Nader A.

    2012-07-22

    Abstract— Demand response (DR) has a great potential to provide balancing services at normal operating conditions and emergency support when a power system is subject to disturbances. Effective control strategies can significantly relieve the balancing burden of conventional generators and reduce investment on generation and transmission expansion. This paper is aimed at modeling electric water heaters (EWH) in households and tests their response to control strategies to implement DR. The open-loop response of EWH to a centralized signal is studied by adjusting temperature settings to provide regulation services; and two types of decentralized controllers are tested to provide frequency support following generator trips. EWH models are included in a simulation platform in DIgSILENT to perform electromechanical simulation, which contains 147 households in a distribution feeder. Simulation results show the dependence of EWH response on water heater usage . These results provide insight suggestions on the need of control strategies to achieve better performance for demand response implementation. Index Terms— Centralized control, decentralized control, demand response, electrical water heater, smart grid

  11. An Analysis of Yip's Global Strategy Model, Using Coca-Cola ...

    African Journals Online (AJOL)

    Analysis of the selected business cases suggest a weak fit between the Yip model of a truly Global strategy ... like Coca-Cola in the beverage industry for effective implementation of a global strategy. ... Keywords: Global Strategy, Leadership.

  12. Energy modelling platforms for policy and strategy support

    International Nuclear Information System (INIS)

    Dyner, I.

    2000-01-01

    The energy field has been dominated by 'hard' modelling approaches by researchers from engineering and economics discipline. The recent trend towards a more liberalised environment moves away from central planning to market-based resource allocation, leading to the creation and use of strategic tools, with much 'softer' specifications, in the 'system-thinking' tradition. This paper presents the use of system dynamics in a generalised way, to provide a platform for integrated energy analysis. Issues of modularity and policy evolution are important in the design of the modelling platform to facilitate its use, and reuse. Hence the concepts of a platform, rather than a model, has to be implemented in a coherent way if it is to provide sustained value for ongoing support to both government policy and corporate strategy. (author)

  13. Communication strategies for two models of discrete energy harvesting

    DEFF Research Database (Denmark)

    Trillingsgaard, Kasper Fløe; Popovski, Petar

    2014-01-01

    Energy harvesting is becoming a viable option for powering small wireless devices. Energy for data transmission is supplied by the nature, such that when a transmission is about to take place in an arbitrary instant, the amount of available energy is a random quantity. The arrived energy is stored...... in a battery and transmissions are interrupted if the battery runs out of energy. We address communication in slot-based energy harvesting systems, where the transmitter communicates with ON-OFF signaling: in each slot it can either choose to transmit (ON) or stay silent (OFF). Two different models...... strategies and compare the slot- with the frame-based model in the case of an errorless transmission channel. Additionally, for the slot-based model and channel with errors, we provide a new proof of the capacity achieved by the save-and-transmit scheme....

  14. Models of Customer Behavior as a Basis of Marketing Strategy

    Directory of Open Access Journals (Sweden)

    T A Ivanova

    2012-06-01

    Full Text Available The article is devoted to the analysis of six main models of customer behavior in contemporary society and the specific tasks of marketing departments of companies at today's stage of development. The given models take into consideration: motives for choosing a product, the degree of product awareness and independence of choice, the degree of customer satisfaction with the product, lines and possibilities of making an impact on customer choice through marketing and promotion stimulation. The author believes that these models may serve as a basis in the formation of effective marketing strategies, as they describe the customers in all the stages of their actions in the process of buying products, accumulating and analyzing the experience of using them.

  15. Modelling wedding marketing strategies: An fsQCA Analysis

    Directory of Open Access Journals (Sweden)

    Anestis Fotiadis

    2018-05-01

    Full Text Available Aim of the study is to develop a model delineating customer perceptions on wedding marketing strategies in Kaohsiung, Taiwan. Main objective of this paper is to analyse a category of special events: the wedding market sector in Kaohsiung, Taiwan by examining how they attract consumers regarding their marketing strategies using the method of fuzzy-set Qualitative Comparative Analysis (fsQCA. Based on a survey to married, in relationship and singles local citizens of Taiwan the relationships between impressions, importance, push factors with decision making was explored. To test the hypotheses of the proposed model a primary research study was conducted employing a mall intercept technique via distribution of a self-administered questionnaire within a cross sectional on-site field research context. A fsQCA modelling approach technique was employed in order to measure, estimate and confirm the different casual paths constructs, as well as to test the significance of the paths between different segments of the wedding industry. Our findings reveal that the presence of importance, push factors and decision making determines the level of consumer perception performance. However, impressions do not show significant impact on consumer perceptions.

  16. A diagnostic tree model for polytomous responses with multiple strategies.

    Science.gov (United States)

    Ma, Wenchao

    2018-04-23

    Constructed-response items have been shown to be appropriate for cognitively diagnostic assessments because students' problem-solving procedures can be observed, providing direct evidence for making inferences about their proficiency. However, multiple strategies used by students make item scoring and psychometric analyses challenging. This study introduces the so-called two-digit scoring scheme into diagnostic assessments to record both students' partial credits and their strategies. This study also proposes a diagnostic tree model (DTM) by integrating the cognitive diagnosis models with the tree model to analyse the items scored using the two-digit rubrics. Both convergent and divergent tree structures are considered to accommodate various scoring rules. The MMLE/EM algorithm is used for item parameter estimation of the DTM, and has been shown to provide good parameter recovery under varied conditions in a simulation study. A set of data from TIMSS 2007 mathematics assessment is analysed to illustrate the use of the two-digit scoring scheme and the DTM. © 2018 The British Psychological Society.

  17. Strategies simulation model for the gas business chain MEGAS

    International Nuclear Information System (INIS)

    Gonzalez, S.M. de; Uzcategui, R.; Brea, E.; Diaz, R.

    1994-01-01

    MEGAS is a simulation model representing fundamental parameters of Corpoven's natural gas and NGL production, handling, processing, transportation and distribution systems in the Venezuelan mid-east, as well as its financial implications. Various strategies regarding development, prices, costs, new business opportunities, production scenarios, demand and energy policies can be evaluated through this model in order to determine, after analyzing the economics results, a set of strategies to follow in the mid and long term. MEGAS could be also used to make risk analysis studies, considering that probabilistic parameters and variables like gas quality, production, demand, plant shutdowns and others are to be represented by their distinctive function. It is possible to set up a probabilistic function for each economic indicator or operating variables with an appropriate experiment design. MEGAS is based on a dynamic simulation language, which facilitates both the real system components representation and the main variables statistical data accumulation. It also allows graphical representation of results and the simulation animation. Demand and price forecasts, new projects, costs and capabilities of the systems are some of the model input data. MEGAS should be considered as a tool that eases the strategic planning of the business, making it possible for the Corporation to foresee changes, both in the domestic and international market, to predict how these changes could affect its business affairs and to visualize different return scenarios

  18. Generation of safe optimised execution strategies for uml models

    DEFF Research Database (Denmark)

    Herbert, Luke Thomas; Herbert-Hansen, Zaza Nadja Lee

    When designing safety critical systems there is a need for verification of safety properties while ensuring system operations have a specific performance profile. We present a novel application of model checking to derive execution strategies, sequences of decisions at workflow branch points...... which optimise a set of reward variables, while simultaneously observing constraints which encode any required safety properties and accounting for the underlying stochastic nature of the system. By evaluating quantitative properties of the generated adversaries we are able to construct an execution...

  19. Application of ABCD Analysis Model for Black Ocean Strategy

    OpenAIRE

    Sreeramana Aithal; Suresh Kumar P. M.; Shailashree V. T.

    2015-01-01

    Strategic planning and decision making has an important role in organizational development and sustainability. Various types of strategies are used in strategic management such as Red ocean strategy, Blue ocean strategy, Green ocean strategy and Purple ocean strategy. These strategies are used in organizations by top level executive managers for long term sustainability of organization and to face or avoid the competition. Based on organizational analysis, it is observed that some...

  20. Uncertainty modeling of CCS investment strategy in China's power sector

    International Nuclear Information System (INIS)

    Zhou, Wenji; Zhu, Bing; Fuss, Sabine; Szolgayova, Jana; Obersteiner, Michael; Fei, Weiyang

    2010-01-01

    The increasing pressure resulting from the need for CO 2 mitigation is in conflict with the predominance of coal in China's energy structure. A possible solution to this tension between climate change and fossil fuel consumption fact could be the introduction of the carbon capture and storage (CCS) technology. However, high cost and other problems give rise to great uncertainty in R and D and popularization of carbon capture technology. This paper presents a real options model incorporating policy uncertainty described by carbon price scenarios (including stochasticity), allowing for possible technological change. This model is further used to determine the best strategy for investing in CCS technology in an uncertain environment in China and the effect of climate policy on the decision-making process of investment into carbon-saving technologies.

  1. Logical Reasoning versus Information Processing in the Dual-Strategy Model of Reasoning

    Science.gov (United States)

    Markovits, Henry; Brisson, Janie; de Chantal, Pier-Luc

    2017-01-01

    One of the major debates concerning the nature of inferential reasoning is between counterexample-based strategies such as mental model theory and statistical strategies underlying probabilistic models. The dual-strategy model, proposed by Verschueren, Schaeken, & d'Ydewalle (2005a, 2005b), which suggests that people might have access to both…

  2. Advanced modelling and numerical strategies in nuclear thermal-hydraulics

    International Nuclear Information System (INIS)

    Staedtke, H.

    2001-01-01

    The first part of the lecture gives a brief review of the current status of nuclear thermal hydraulics as it forms the basis of established system codes like TRAC, RELAP5, CATHARE or ATHLET. Specific emphasis is given to the capabilities and limitations of the underlying physical modelling and numerical solution strategies with regard to the description of complex transient two-phase flow and heat transfer conditions as expected to occur in PWR reactors during off-normal and accident conditions. The second part of the lecture focuses on new challenges and future needs in nuclear thermal-hydraulics which might arise with regard to re-licensing of old plants using bestestimate methodologies or the design and safety analysis of Advanced Light Water Reactors relying largely on passive safety systems. In order to meet these new requirements various advanced modelling and numerical techniques will be discussed including extended wellposed (hyperbolic) two-fluid models, explicit modelling of interfacial area transport or higher order numerical schemes allowing a high resolution of local multi-dimensional flow processes.(author)

  3. ATL with strategy contexts: Expressiveness and Model Checking.

    OpenAIRE

    Da Costa , Arnaud; Laroussinie , François; Markey , Nicolas

    2010-01-01

    We study the alternating-time temporal logics ATL and ATL* extended with strategy contexts: these make agents commit to their strategies during the evaluation of formulas, contrary to plain ATL and ATL* where strategy quantifiers reset previously selected strategies. We illustrate the important expressive power of strategy contexts by proving that they make the extended logics, namely ATLsc and ATLsc*, equally expressive: any formula in ATLsc* can be translated into an equivalent, linear-...

  4. Strategies for fitting nonlinear ecological models in R, AD Model Builder, and BUGS

    DEFF Research Database (Denmark)

    Bolker, B.M.; Gardner, B.; Maunder, M.

    2013-01-01

    Ecologists often use nonlinear fitting techniques to estimate the parameters of complex ecological models, with attendant frustration. This paper compares three open-source model fitting tools and discusses general strategies for defining and fitting models. R is convenient and (relatively) easy...... to learn, AD Model Builder is fast and robust but comes with a steep learning curve, while BUGS provides the greatest flexibility at the price of speed. Our model-fitting suggestions range from general cultural advice (where possible, use the tools and models that are most common in your subfield...

  5. More efficient evolutionary strategies for model calibration with watershed model for demonstration

    Science.gov (United States)

    Baggett, J. S.; Skahill, B. E.

    2008-12-01

    Evolutionary strategies allow automatic calibration of more complex models than traditional gradient based approaches, but they are more computationally intensive. We present several efficiency enhancements for evolution strategies, many of which are not new, but when combined have been shown to dramatically decrease the number of model runs required for calibration of synthetic problems. To reduce the number of expensive model runs we employ a surrogate objective function for an adaptively determined fraction of the population at each generation (Kern et al., 2006). We demonstrate improvements to the adaptive ranking strategy that increase its efficiency while sacrificing little reliability and further reduce the number of model runs required in densely sampled parts of parameter space. Furthermore, we include a gradient individual in each generation that is usually not selected when the search is in a global phase or when the derivatives are poorly approximated, but when selected near a smooth local minimum can dramatically increase convergence speed (Tahk et al., 2007). Finally, the selection of the gradient individual is used to adapt the size of the population near local minima. We show, by incorporating these enhancements into the Covariance Matrix Adaption Evolution Strategy (CMAES; Hansen, 2006), that their synergetic effect is greater than their individual parts. This hybrid evolutionary strategy exploits smooth structure when it is present but degrades to an ordinary evolutionary strategy, at worst, if smoothness is not present. Calibration of 2D-3D synthetic models with the modified CMAES requires approximately 10%-25% of the model runs of ordinary CMAES. Preliminary demonstration of this hybrid strategy will be shown for watershed model calibration problems. Hansen, N. (2006). The CMA Evolution Strategy: A Comparing Review. In J.A. Lozano, P. Larrañga, I. Inza and E. Bengoetxea (Eds.). Towards a new evolutionary computation. Advances in estimation of

  6. Tension-compression asymmetry modelling: strategies for anisotropy parameters identification.

    Directory of Open Access Journals (Sweden)

    Barros Pedro

    2016-01-01

    Full Text Available This work presents details concerning the strategies and algorithms adopted in the fully implicit FE solver DD3IMP to model the orthotropic behavior of metallic sheets and the procedure for anisotropy parameters identification. The work is focused on the yield criterion developed by Cazacu, Plunkett and Barlat, 2006 [1], which accounts for both tension–compression asymmetry and orthotropic plastic behavior. The anisotropy parameters for a 2090-T3 aluminum alloy are identified accounting, or not, for the tension-compression asymmetry. The numerical simulation of a cup drawing is performed for this material, highlighting the importance of considering tension-compression asymmetry in the prediction of the earing profile, for materials with cubic structure, even if this phenomenon is relatively small.

  7. PERUMUSAN STRATEGI PEMASARAN FRY COUNTER DENGAN PENDEKATAN MODEL AIDA

    Directory of Open Access Journals (Sweden)

    Andi Oktoriyana

    2014-05-01

    Full Text Available This research examined factors which are mentioned in various literatures that have influence on AIDA models to buy fry counter which are attention, interest, and desire. The model also influenced by perceived attributes, personal characteristics, and external factors. Furthermore, the analysis result become a basic for formulating the marketing strategy of fry counter as an innovative product. Analysis was carried out using Structural Equation Modeling. The data for this study were collected from 152 respondents who were fish farmers located in Sukabumi Regency, West Java Province. This research found that external and internal factors influenced positively perceived attributes faktors. The external and perceived attributes factors also influenced positively attention factor. The external factor had negative influence but internal and attention factors had positive influence on consumer’s interest. Perceived attributes and interest factors influenced positively desire factor. Managerial implications is elaborated in the discussion.

  8. Evaluation of targeted influenza vaccination strategies via population modeling.

    Directory of Open Access Journals (Sweden)

    John Glasser

    Full Text Available BACKGROUND: Because they can generate comparable predictions, mathematical models are ideal tools for evaluating alternative drug or vaccine allocation strategies. To remain credible, however, results must be consistent. Authors of a recent assessment of possible influenza vaccination strategies conclude that older children, adolescents, and young adults are the optimal targets, no matter the objective, and argue for vaccinating them. Authors of two earlier studies concluded, respectively, that optimal targets depend on objectives and cautioned against changing policy. Which should we believe? METHODS AND FINDINGS: In matrices whose elements are contacts between persons by age, the main diagonal always predominates, reflecting contacts between contemporaries. Indirect effects (e.g., impacts of vaccinating one group on morbidity or mortality in others result from off-diagonal elements. Mixing matrices based on periods in proximity with others have greater sub- and super-diagonals, reflecting contacts between parents and children, and other off-diagonal elements (reflecting, e.g., age-independent contacts among co-workers, than those based on face-to-face conversations. To assess the impact of targeted vaccination, we used a time-usage study's mixing matrix and allowed vaccine efficacy to vary with age. And we derived mortality rates either by dividing observed deaths attributed to pneumonia and influenza by average annual cases from a demographically-realistic SEIRS model or by multiplying those rates by ratios of (versus adding to them differences between pandemic and pre-pandemic mortalities. CONCLUSIONS: In our simulations, vaccinating older children, adolescents, and young adults averts the most cases, but vaccinating either younger children and older adults or young adults averts the most deaths, depending on the age distribution of mortality. These results are consistent with those of the earlier studies.

  9. Business Model Innovation Portfolio Strategy for Growth Under Product-Market Configurations

    OpenAIRE

    Bert Verhoeven; Lester W. Johnson

    2017-01-01

    Purpose: The research links three concepts: product market growth strategy, the magnitude of innovation and Business Model Innovation, merging them together into a dynamic Business Model Innovation strategy framework. Design/Methodology/Approach: The paper is conceptual and exploratory in nature and builds on existing literature and the author’s experience with developing business models. Findings: The BMI strategy framework can help managers establish a BMI portfolio strategy followi...

  10. Modeling a Strategy for the War on Terrorism

    National Research Council Canada - National Science Library

    Henderson, Darral

    2002-01-01

    .... This paper discusses a strategy for conducting the war on terrorism in terms of a system and how that strategy must be adjusted over the long-term to compensate for fluctuating components of the war on terrorism...

  11. Modeling Turkey’s future LNG supply security strategy

    International Nuclear Information System (INIS)

    Efe Biresselioglu, Mehmet; Hakan Demir, Muhittin; Kandemir, Cansu

    2012-01-01

    Turkey was among those countries which decided to increase its natural gas consumption in the 1990s, due to its relative low cost and lack of impact on the environment. However, a heavy dependence on imports, from Algeria, Qatar and Nigeria, respectively, creates a threat to energy security, both in terms of source and supply diversity. Accordingly, we follow an analytical approach to identify the accuracy of our assumption, considering the current economic, political and security risk. To this end, we formulate and solve a mixed integer programming model that determines the optimal sourcing strategy for Turkey’s increasing LNG demand. This model demonstrates a number of alternative policy options for LNG supply. Furthermore, we consider that increasing the proportion of LNG in the overall gas supply will contribute to the aim of improving Turkey’s level of energy security. - Highlights: ► Turkey’s best policy option is to increase the share of LNG. ► Turkey’s main suppliers of LNG will be Algeria, Egypt, Nigeria, and Trinidad and Tobago. ► Norway, Libya, and Oman contribute to the supply with rather smaller shares. ► With high risk scenario Algeria, Egypt, Nigeria and Libya will not be suppliers. ► Oman and Qatar will cover; even though they are high-cost suppliers.

  12. Modeling Test and Treatment Strategies for Presymptomatic Alzheimer Disease

    Science.gov (United States)

    Burke, James F.; Langa, Kenneth M.; Hayward, Rodney A.; Albin, Roger L.

    2014-01-01

    Objectives In this study, we developed a model of presymptomatic treatment of Alzheimer disease (AD) after a screening diagnostic evaluation and explored the circumstances required for an AD prevention treatment to produce aggregate net population benefit. Methods Monte Carlo simulation methods were used to estimate outcomes in a simulated population derived from data on AD incidence and mortality. A wide variety of treatment parameters were explored. Net population benefit was estimated in aggregated QALYs. Sensitivity analyses were performed by individually varying the primary parameters. Findings In the base-case scenario, treatment effects were uniformly positive, and net benefits increased with increasing age at screening. A highly efficacious treatment (i.e. relative risk 0.6) modeled in the base-case is estimated to save 20 QALYs per 1000 patients screened and 221 QALYs per 1000 patients treated. Conclusions Highly efficacious presymptomatic screen and treat strategies for AD are likely to produce substantial aggregate population benefits that are likely greater than the benefits of aspirin in primary prevention of moderate risk cardiovascular disease (28 QALYS per 1000 patients treated), even in the context of an imperfect treatment delivery environment. PMID:25474698

  13. On the ideal and real energy conversion in a straight bladed vertical axis wind turbine. The actuator cylinder flow model compared with experiment

    Energy Technology Data Exchange (ETDEWEB)

    Aaagard Madsen, H.

    1983-01-01

    The ideal and the real energy conversion in a straight bladed vertical axis wind turbine (VAWT) with variable pitch has been studied on basis of the actuator cylinder flow model and experimental data from free wind tests on a 9 m/sup 2/ turbine. Particularly, the theoretical upper power limit of VAWT's has been focused upon in the light of the already existing theories for horizontal axis wind turbines (HAWT's). A remarkable result, differing from prior theories, has turned out through the computations with the actuator cylinder flow model and that is: The maximum ideal power coefficient for VAWT's seams neither to be bounded by the Lanchester-Betz power coefficient limit of 16/27 (actuator disc concept), nor by Glauert's ideal power coefficient curve (taking into account the tip speed ratio), both limits derived with particular reference to HAWT's. Concerning the agreement between analysis and the measurements of the power coefficient, the rotor drag coefficient and the flow velocity vector adjacent to the swept area, it was in general found to be good. However, there seems still to be need for future research on the influence of turbulence in the free wind and dynamic stall on the real energy conversion in VAWT's.

  14. Comparison of aerodynamic models for Vertical Axis Wind Turbines

    International Nuclear Information System (INIS)

    Ferreira, C Simão; Madsen, H Aagaard; Barone, M; Roscher, B; Deglaire, P; Arduin, I

    2014-01-01

    Multi-megawatt Vertical Axis Wind Turbines (VAWTs) are experiencing an increased interest for floating offshore applications. However, VAWT development is hindered by the lack of fast, accurate and validated simulation models. This work compares six different numerical models for VAWTS: a multiple streamtube model, a double-multiple streamtube model, the actuator cylinder model, a 2D potential flow panel model, a 3D unsteady lifting line model, and a 2D conformal mapping unsteady vortex model. The comparison covers rotor configurations with two NACA0015 blades, for several tip speed ratios, rotor solidity and fixed pitch angle, included heavily loaded rotors, in inviscid flow. The results show that the streamtube models are inaccurate, and that correct predictions of rotor power and rotor thrust are an effect of error cancellation which only occurs at specific configurations. The other four models, which explicitly model the wake as a system of vorticity, show mostly differences due to the instantaneous or time averaged formulation of the loading and flow, for which further research is needed

  15. Comparison of aerodynamic models for Vertical Axis Wind Turbines

    Science.gov (United States)

    Simão Ferreira, C.; Aagaard Madsen, H.; Barone, M.; Roscher, B.; Deglaire, P.; Arduin, I.

    2014-06-01

    Multi-megawatt Vertical Axis Wind Turbines (VAWTs) are experiencing an increased interest for floating offshore applications. However, VAWT development is hindered by the lack of fast, accurate and validated simulation models. This work compares six different numerical models for VAWTS: a multiple streamtube model, a double-multiple streamtube model, the actuator cylinder model, a 2D potential flow panel model, a 3D unsteady lifting line model, and a 2D conformal mapping unsteady vortex model. The comparison covers rotor configurations with two NACA0015 blades, for several tip speed ratios, rotor solidity and fixed pitch angle, included heavily loaded rotors, in inviscid flow. The results show that the streamtube models are inaccurate, and that correct predictions of rotor power and rotor thrust are an effect of error cancellation which only occurs at specific configurations. The other four models, which explicitly model the wake as a system of vorticity, show mostly differences due to the instantaneous or time averaged formulation of the loading and flow, for which further research is needed.

  16. A computational approach to compare regression modelling strategies in prediction research.

    Science.gov (United States)

    Pajouheshnia, Romin; Pestman, Wiebe R; Teerenstra, Steven; Groenwold, Rolf H H

    2016-08-25

    It is often unclear which approach to fit, assess and adjust a model will yield the most accurate prediction model. We present an extension of an approach for comparing modelling strategies in linear regression to the setting of logistic regression and demonstrate its application in clinical prediction research. A framework for comparing logistic regression modelling strategies by their likelihoods was formulated using a wrapper approach. Five different strategies for modelling, including simple shrinkage methods, were compared in four empirical data sets to illustrate the concept of a priori strategy comparison. Simulations were performed in both randomly generated data and empirical data to investigate the influence of data characteristics on strategy performance. We applied the comparison framework in a case study setting. Optimal strategies were selected based on the results of a priori comparisons in a clinical data set and the performance of models built according to each strategy was assessed using the Brier score and calibration plots. The performance of modelling strategies was highly dependent on the characteristics of the development data in both linear and logistic regression settings. A priori comparisons in four empirical data sets found that no strategy consistently outperformed the others. The percentage of times that a model adjustment strategy outperformed a logistic model ranged from 3.9 to 94.9 %, depending on the strategy and data set. However, in our case study setting the a priori selection of optimal methods did not result in detectable improvement in model performance when assessed in an external data set. The performance of prediction modelling strategies is a data-dependent process and can be highly variable between data sets within the same clinical domain. A priori strategy comparison can be used to determine an optimal logistic regression modelling strategy for a given data set before selecting a final modelling approach.

  17. Strategies for fitting nonlinear ecological models in R, AD Model Builder, and BUGS

    Science.gov (United States)

    Bolker, Benjamin M.; Gardner, Beth; Maunder, Mark; Berg, Casper W.; Brooks, Mollie; Comita, Liza; Crone, Elizabeth; Cubaynes, Sarah; Davies, Trevor; de Valpine, Perry; Ford, Jessica; Gimenez, Olivier; Kéry, Marc; Kim, Eun Jung; Lennert-Cody, Cleridy; Magunsson, Arni; Martell, Steve; Nash, John; Nielson, Anders; Regentz, Jim; Skaug, Hans; Zipkin, Elise

    2013-01-01

    1. Ecologists often use nonlinear fitting techniques to estimate the parameters of complex ecological models, with attendant frustration. This paper compares three open-source model fitting tools and discusses general strategies for defining and fitting models. 2. R is convenient and (relatively) easy to learn, AD Model Builder is fast and robust but comes with a steep learning curve, while BUGS provides the greatest flexibility at the price of speed. 3. Our model-fitting suggestions range from general cultural advice (where possible, use the tools and models that are most common in your subfield) to specific suggestions about how to change the mathematical description of models to make them more amenable to parameter estimation. 4. A companion web site (https://groups.nceas.ucsb.edu/nonlinear-modeling/projects) presents detailed examples of application of the three tools to a variety of typical ecological estimation problems; each example links both to a detailed project report and to full source code and data.

  18. Aligning economic impact with environmental benefits: a green strategy model

    OpenAIRE

    Gu, Q.; Lago, P.; Potenza, S.

    2012-01-01

    To achieve lower energy consumption many green strategies (e.g. virtualize applications and consolidate them on shared server machines, or optimize the usage of the private cloud by opening up to external consumers) have been discussed. In practice, however, the major incentive for a company to go green is reducing costs. While green strategies often focus on technical and environmental issues, they hardly address the economic impact that they may bring. If green strategies do not lead to an ...

  19. Simulating Dynamic Stall Effects for Vertical Axis Wind Turbines Applying a Double Multiple Streamtube Model

    Directory of Open Access Journals (Sweden)

    Eduard Dyachuk

    2015-02-01

    Full Text Available The complex unsteady aerodynamics of vertical axis wind turbines (VAWT poses significant challenges to the simulation tools. Dynamic stall is one of the phenomena associated with the unsteady conditions for VAWTs, and it is in the focus of the study. Two dynamic stall models are compared: the widely-used Gormont model and a Leishman–Beddoes-type model. The models are included in a double multiple streamtube model. The effects of flow curvature and flow expansion are also considered. The model results are assessed against the measured data on a Darrieus turbine with curved blades. To study the dynamic stall effects, the comparison of force coefficients between the simulations and experiments is done at low tip speed ratios. Simulations show that the Leishman–Beddoes model outperforms the Gormont model for all tested conditions.

  20. Multiple models guide strategies for agricultural nutrient reductions

    Science.gov (United States)

    Scavia, Donald; Kalcic, Margaret; Muenich, Rebecca Logsdon; Read, Jennifer; Aloysius, Noel; Bertani, Isabella; Boles, Chelsie; Confesor, Remegio; DePinto, Joseph; Gildow, Marie; Martin, Jay; Redder, Todd; Robertson, Dale M.; Sowa, Scott P.; Wang, Yu-Chen; Yen, Haw

    2017-01-01

    In response to degraded water quality, federal policy makers in the US and Canada called for a 40% reduction in phosphorus (P) loads to Lake Erie, and state and provincial policy makers in the Great Lakes region set a load-reduction target for the year 2025. Here, we configured five separate SWAT (US Department of Agriculture's Soil and Water Assessment Tool) models to assess load reduction strategies for the agriculturally dominated Maumee River watershed, the largest P source contributing to toxic algal blooms in Lake Erie. Although several potential pathways may achieve the target loads, our results show that any successful pathway will require large-scale implementation of multiple practices. For example, one successful pathway involved targeting 50% of row cropland that has the highest P loss in the watershed with a combination of three practices: subsurface application of P fertilizers, planting cereal rye as a winter cover crop, and installing buffer strips. Achieving these levels of implementation will require local, state/provincial, and federal agencies to collaborate with the private sector to set shared implementation goals and to demand innovation and honest assessments of water quality-related programs, policies, and partnerships.

  1. Verification and validation of the decision analysis model for assessment of TWRS waste treatment strategies

    International Nuclear Information System (INIS)

    Awadalla, N.G.; Eaton, S.C.F.

    1996-01-01

    This document is the verification and validation final report for the Decision Analysis Model for Assessment of Tank Waste Remediation System Waste Treatment Strategies. This model is also known as the INSIGHT Model

  2. IMPLEMENTASI MODEL STRATEGI PENINGKATAN KINERJA BALAI PENYULUHAN PERTANIAN (BPP) DI KABUPATEN MAROS, SULAWESI SELATAN

    OpenAIRE

    djalaluddin, Akhsan; Jamil, Muh.Hatta; Tenriawaru, A Nixia; M. Rukka, Rusli

    2013-01-01

    Implementasi Model Strategi Peningkatan Kinerja Balai Penyuluhan Pertanian bertujuan mengungkapkan dan menyusun desain modul yang diikuti dengan proses transfer pengetahuan dan keterampilan melalui pembentukan model pengembangan kelembagaan BPP. Di samping itu, melalui penelitian tahap II ini, dokumen yang dihasilkan dapat menjadi titik pijak prumusan kebijakan pengembangan BPP khususnya kebijakan peningkatan kinerja BPP. Sembari mensosialisasikan model strategi peningkatan kinerja BPP yang ...

  3. Strategies and models for agricultural sustainability in developing Asian countries.

    Science.gov (United States)

    Kesavan, P C; Swaminathan, M S

    2008-02-27

    The green revolution of the 1960s and 1970s which resulted in dramatic yield increases in the developing Asian countries is now showing signs of fatigue in productivity gains. Intensive agriculture practiced without adherence to the scientific principles and ecological aspects has led to loss of soil health, and depletion of freshwater resources and agrobiodiversity. With progressive diversion of arable land for non-agricultural purposes, the challenge of feeding the growing population without, at the same time, annexing more forestland and depleting the rest of life is indeed daunting. Further, even with food availability through production/procurement, millions of marginal farming, fishing and landless rural families have very low or no access to food due to lack of income-generating livelihoods. Approximately 200 million rural women, children and men in India alone fall in this category. Under these circumstances, the evergreen revolution (pro-nature, pro-poor, pro-women and pro-employment/livelihood oriented ecoagriculture) under varied terms are proposed for achieving productivity in perpetuity. In the proposed 'biovillage paradigm', eco-friendly agriculture is promoted along with on- and non-farm eco-enterprises based on sustainable management of natural resources. Concurrently, the modern ICT-based village knowledge centres provide time- and locale-specific, demand-driven information needed for evergreen revolution and ecotechnologies. With a system of 'farm and marine production by masses', the twin goals of ecoagriculture and eco-livelihoods are addressed. The principles, strategies and models of these are briefly discussed in this paper.

  4. Exploring the Interconnectedness among Strategy Development, Shared Mental Models, Organisational Learning and Organisational Change

    Science.gov (United States)

    Malan, Renee

    2011-01-01

    The cognitive psychological processes related to learning and change behaviour are factors that impact on organisational strategy development. Strategy development is dependent on strategic thinking that is reciprocally influenced by shared mental models, organisational learning and organisational change. Although strategy development, shared…

  5. Work Strategies: The Development and Testing of a Model.

    Science.gov (United States)

    1986-03-01

    strategies (e.g., Craik & Lockhart , 1972); hemispheric process - -7 ing differences (e.g., Seamon & Gazzaniga, 1973); problem-solving strategies (e.g...Charness, N. (1931). Aging and skilled problem solving. 3ournal of Experimental Psychology: General, 110, 21-38. Craik , F. I. \\., & Lockhart , R. S...1972). Levels of processing : A framework for memory research. Journal of Verbal Learning and Verbal Behavior, L1, 671-684. 3ansereau, D. F., McDonald

  6. A Mobile Application Development Strategy-Finding Model

    OpenAIRE

    MBAYEN MBAYEN, GHISLAIN EDGARD

    2013-01-01

    Nowadays there are several different types of ways to build a mobile application, through web technologies, or through mobile manufacturers’ languages. Thus, in this study we focus on the three major mobile application development strategies: Native, Hybrid, and Web to Native. This plurality of solutions renders the selection of a mobile application development strategy complex. Hence, this study aims at understanding how developers deal with the selection of a mobile development approach. Th...

  7. Neural Underpinnings of Decision Strategy Selection: A Review and a Theoretical Model.

    Science.gov (United States)

    Wichary, Szymon; Smolen, Tomasz

    2016-01-01

    In multi-attribute choice, decision makers use decision strategies to arrive at the final choice. What are the neural mechanisms underlying decision strategy selection? The first goal of this paper is to provide a literature review on the neural underpinnings and cognitive models of decision strategy selection and thus set the stage for a neurocognitive model of this process. The second goal is to outline such a unifying, mechanistic model that can explain the impact of noncognitive factors (e.g., affect, stress) on strategy selection. To this end, we review the evidence for the factors influencing strategy selection, the neural basis of strategy use and the cognitive models of this process. We also present the Bottom-Up Model of Strategy Selection (BUMSS). The model assumes that the use of the rational Weighted Additive strategy and the boundedly rational heuristic Take The Best can be explained by one unifying, neurophysiologically plausible mechanism, based on the interaction of the frontoparietal network, orbitofrontal cortex, anterior cingulate cortex and the brainstem nucleus locus coeruleus. According to BUMSS, there are three processes that form the bottom-up mechanism of decision strategy selection and lead to the final choice: (1) cue weight computation, (2) gain modulation, and (3) weighted additive evaluation of alternatives. We discuss how these processes might be implemented in the brain, and how this knowledge allows us to formulate novel predictions linking strategy use and neural signals.

  8. Neural Underpinnings of Decision Strategy Selection: A Review and a Theoretical Model

    Science.gov (United States)

    Wichary, Szymon; Smolen, Tomasz

    2016-01-01

    In multi-attribute choice, decision makers use decision strategies to arrive at the final choice. What are the neural mechanisms underlying decision strategy selection? The first goal of this paper is to provide a literature review on the neural underpinnings and cognitive models of decision strategy selection and thus set the stage for a neurocognitive model of this process. The second goal is to outline such a unifying, mechanistic model that can explain the impact of noncognitive factors (e.g., affect, stress) on strategy selection. To this end, we review the evidence for the factors influencing strategy selection, the neural basis of strategy use and the cognitive models of this process. We also present the Bottom-Up Model of Strategy Selection (BUMSS). The model assumes that the use of the rational Weighted Additive strategy and the boundedly rational heuristic Take The Best can be explained by one unifying, neurophysiologically plausible mechanism, based on the interaction of the frontoparietal network, orbitofrontal cortex, anterior cingulate cortex and the brainstem nucleus locus coeruleus. According to BUMSS, there are three processes that form the bottom-up mechanism of decision strategy selection and lead to the final choice: (1) cue weight computation, (2) gain modulation, and (3) weighted additive evaluation of alternatives. We discuss how these processes might be implemented in the brain, and how this knowledge allows us to formulate novel predictions linking strategy use and neural signals. PMID:27877103

  9. Neural underpinnings of decision strategy selection: a review and a theoretical model

    Directory of Open Access Journals (Sweden)

    Szymon Wichary

    2016-11-01

    Full Text Available In multi-attribute choice, decision makers use various decision strategies to arrive at the final choice. What are the neural mechanisms underlying decision strategy selection? The first goal of this paper is to provide a literature review on the neural underpinnings and cognitive models of decision strategy selection and thus set the stage for a unifying neurocognitive model of this process. The second goal is to outline such a unifying, mechanistic model that can explain the impact of noncognitive factors (e.g. affect, stress on strategy selection. To this end, we review the evidence for the factors influencing strategy selection, the neural basis of strategy use and the cognitive models explaining this process. We also present the neurocognitive Bottom-Up Model of Strategy Selection (BUMSS. The model assumes that the use of the rational, normative Weighted Additive strategy and the boundedly rational heuristic Take The Best can be explained by one unifying, neurophysiologically plausible mechanism, based on the interaction of the frontoparietal network, orbitofrontal cortex, anterior cingulate cortex and the brainstem nucleus locus coeruleus. According to BUMSS, there are three processes that form the bottom-up mechanism of decision strategy selection and lead to the final choice: 1 cue weight computation, 2 gain modulation, and 3 weighted additive evaluation of alternatives. We discuss how these processes might be implemented in the brain, and how this knowledge allows us to formulate novel predictions linking strategy use and neurophysiological indices.

  10. Interpersonal success factors for strategy implementation: a case study using group model building

    OpenAIRE

    Rodney J Scott; Robert Y Cavana; Donald Cameron

    2015-01-01

    Strategy implementation has been identified as an area of system dynamics literature requiring greater attention. Most strategies fail to be implemented successfully, and processes for effectively implementing strategy are yet to be fully explained and explored. The reported interpersonal success factors for strategy implementation are reported outcomes for group model building, suggesting potential applicability. A case study using validated survey methods yielded promising results, and sugg...

  11. Strategies to Automatically Derive a Process Model from a Configurable Process Model Based on Event Data

    Directory of Open Access Journals (Sweden)

    Mauricio Arriagada-Benítez

    2017-10-01

    Full Text Available Configurable process models are frequently used to represent business workflows and other discrete event systems among different branches of large organizations: they unify commonalities shared by all branches and describe their differences, at the same time. The configuration of such models is usually done manually, which is challenging. On the one hand, when the number of configurable nodes in the configurable process model grows, the size of the search space increases exponentially. On the other hand, the person performing the configuration may lack the holistic perspective to make the right choice for all configurable nodes at the same time, since choices influence each other. Nowadays, information systems that support the execution of business processes create event data reflecting how processes are performed. In this article, we propose three strategies (based on exhaustive search, genetic algorithms and a greedy heuristic that use event data to automatically derive a process model from a configurable process model that better represents the characteristics of the process in a specific branch. These strategies have been implemented in our proposed framework and tested in both business-like event logs as recorded in a higher educational enterprise resource planning system and a real case scenario involving a set of Dutch municipalities.

  12. Regression modeling strategies with applications to linear models, logistic and ordinal regression, and survival analysis

    CERN Document Server

    Harrell , Jr , Frank E

    2015-01-01

    This highly anticipated second edition features new chapters and sections, 225 new references, and comprehensive R software. In keeping with the previous edition, this book is about the art and science of data analysis and predictive modeling, which entails choosing and using multiple tools. Instead of presenting isolated techniques, this text emphasizes problem solving strategies that address the many issues arising when developing multivariable models using real data and not standard textbook examples. It includes imputation methods for dealing with missing data effectively, methods for fitting nonlinear relationships and for making the estimation of transformations a formal part of the modeling process, methods for dealing with "too many variables to analyze and not enough observations," and powerful model validation techniques based on the bootstrap.  The reader will gain a keen understanding of predictive accuracy, and the harm of categorizing continuous predictors or outcomes.  This text realistically...

  13. Combination strategies for pandemic influenza response - a systematic review of mathematical modeling studies

    Directory of Open Access Journals (Sweden)

    Lee Vernon J

    2009-12-01

    Full Text Available Abstract Background Individual strategies in pandemic preparedness plans may not reduce the impact of an influenza pandemic. Methods We searched modeling publications through PubMed and associated references from 1990 to 30 September 2009. Inclusion criteria were modeling papers quantifying the effectiveness of combination strategies, both pharmaceutical and non-pharmaceutical. Results Nineteen modeling papers on combination strategies were selected. Four studies examined combination strategies on a global scale, 14 on single countries, and one on a small community. Stochastic individual-based modeling was used in nine studies, stochastic meta-population modeling in five, and deterministic compartmental modeling in another five. As part of combination strategies, vaccination was explored in eight studies, antiviral prophylaxis and/or treatment in 16, area or household quarantine in eight, case isolation in six, social distancing measures in 10 and air travel restriction in six studies. Two studies suggested a high probability of successful influenza epicenter containment with combination strategies under favorable conditions. During a pandemic, combination strategies delayed spread, reduced overall number of cases, and delayed and reduced peak attack rate more than individual strategies. Combination strategies remained effective at high reproductive numbers compared with single strategy. Global cooperative strategies, including redistribution of antiviral drugs, were effective in reducing the global impact and attack rates of pandemic influenza. Conclusion Combination strategies increase the effectiveness of individual strategies. They include pharmaceutical (antiviral agents, antibiotics and vaccines and non-pharmaceutical interventions (case isolation, quarantine, personal hygiene measures, social distancing and travel restriction. Local epidemiological and modeling studies are needed to validate efficacy and feasibility.

  14. Strategies to Enhance Online Learning Teams. Team Assessment and Diagnostics Instrument and Agent-based Modeling

    Science.gov (United States)

    2010-08-12

    Strategies to Enhance Online Learning Teams Team Assessment and Diagnostics Instrument and Agent-based Modeling Tristan E. Johnson, Ph.D. Learning ...REPORT DATE AUG 2010 2. REPORT TYPE 3. DATES COVERED 00-00-2010 to 00-00-2010 4. TITLE AND SUBTITLE Strategies to Enhance Online Learning ...TeamsTeam Strategies to Enhance Online Learning Teams: Team Assessment and Diagnostics Instrument and Agent-based Modeling 5a. CONTRACT NUMBER 5b. GRANT

  15. Implementing Strategy in a Budget: A Model of the Coast Guard Reserve

    OpenAIRE

    Bromund, Carl Douglas

    1990-01-01

    Approved for public release; distribution is unlimited. This thesis discusses the managment strategy of the Coast Guard Reserve; it examines the formulation and implmentation of strateqy. A model to develop and implement strategy is proposed, which defines the role of the budget in this strategic management process. The recent strategy of the Coast Guard Reserve is analyzed using this model.. This analysis seems to indicate that the Coast Guard Reserve had no explicit strate...

  16. Monitoring strategies and scale appropriate hydrologic and biogeochemical modelling for natural resource management

    DEFF Research Database (Denmark)

    Bende-Michl, Ulrike; Volk, Martin; Harmel, Daren

    2011-01-01

    This short communication paper presents recommendations for developing scale-appropriate monitoring and modelling strategies to assist decision making in natural resource management (NRM). These ideas presented here were discussed in the session (S5) ‘Monitoring strategies and scale...... and communication between researcher and model developer on the one side, and natural resource managers and the model users on the other side to increase knowledge in: 1) the limitations and uncertainties of current monitoring and modelling strategies, 2) scale-dependent linkages between monitoring and modelling...

  17. Group Coaching on Pre-School Teachers' Implementation of Pyramid Model Strategies: A Program Description

    Science.gov (United States)

    Fettig, Angel; Artman-Meeker, Kathleen

    2016-01-01

    The purpose of this article was to describe a group coaching model and present preliminary evidence of its impact on teachers' implementation of Pyramid Model practices. In particular, we described coaching strategies used to support teachers in reflecting and problem solving on the implementation of the evidence-based strategies. Preliminary…

  18. Building Bridges: Seeking Structure and Direction for Higher Education Motivated Learning Strategy Models

    Science.gov (United States)

    Fryer, Luke K.

    2017-01-01

    Many of our current higher education (HE) learning strategy models intersect at important points. At the same time, these theories also often demonstrate important unique perspectives on student learning within HE. Currently, research with one learning strategy model rarely leads to developments in others, as each group of researchers works in…

  19. Identifying Multiple Levels of Discussion-Based Teaching Strategies for Constructing Scientific Models

    Science.gov (United States)

    Williams, Grant; Clement, John

    2015-01-01

    This study sought to identify specific types of discussion-based strategies that two successful high school physics teachers using a model-based approach utilized in attempting to foster students' construction of explanatory models for scientific concepts. We found evidence that, in addition to previously documented dialogical strategies that…

  20. Sales Training for Army Recruiter Success: Modeling the Sales Strategies and Skills of Excellent Recruiters

    Science.gov (United States)

    1987-11-01

    strategies used by excellent Army recruiters. Neurolinguistic programming (NLP) was used as the protocol for modeling performance and acquiring...Behavioral and Social Sciences 3001 Eisenhower Avenue, Alexandria, VA 22333-5600 10. PROGRAM ELEMENT. PROJECT. TASK ARE* 4 WORK UNIT...Modeling ’Expert knowledge,, Neurolinguistics Knowledge engineering; Recruiting Sales, &’ Sales cycle Sales skills Sales strategies 20

  1. Reachability and Real-Time Actuation Strategies for the Active SLIP Model

    Science.gov (United States)

    2015-06-01

    time. In gen- eral, animals’ anatomy is far more complex than what the SLIP model captures, due to the presence of joints, ankles , knees, hips, leg...strategies for locomotion. These strategies can then be applied to an anchor , a more complex and realistic model to mimic the animal’s morphology and...model. As clearly explained in [1], the ideal SLIP model is a template that can then be ” anchored ” to systems with more complex dynamics. The prototype

  2. Developing Argumentation Strategies in Electronic Dialogs: Is Modeling Effective?

    Science.gov (United States)

    Mayweg-Paus, Elisabeth; Macagno, Fabrizio; Kuhn, Deanna

    2016-01-01

    The study presented here examines how interacting with a more capable interlocutor influences use of argumentation strategies in electronic discourse. To address this question, 54 young adolescents participating in an intervention centered on electronic peer dialogs were randomly assigned to either an experimental or control condition. In both…

  3. Modeling an impact control strategy using HyPA

    NARCIS (Netherlands)

    Cuijpers, P.J.L.; Reniers, M.A.; Cassandras, C.G.; Giua, A.; Seatzu, C.; Zaytoon, J.

    2006-01-01

    We analyze a control strategy for the pick-and-place module of a component mounting device.We use a combination of techniques from bondgraph-theory, systems theory, process algebra and differential algebra to achieve this, and we show how the hybrid process algebra HyPA aides us in combining these

  4. Aligning economic impact with environmental benefits: a green strategy model

    NARCIS (Netherlands)

    Gu, Q.; Lago, P.; Potenza, S.

    2012-01-01

    To achieve lower energy consumption many green strategies (e.g. virtualize applications and consolidate them on shared server machines, or optimize the usage of the private cloud by opening up to external consumers) have been discussed. In practice, however, the major incentive for a company to go

  5. Considerations on Modeling Strategies of the Financial Result

    Directory of Open Access Journals (Sweden)

    Lucian Cernuşca

    2012-12-01

    Full Text Available This study's objective is to highlight some of the strategies to maximize or minimize the accounting result, situated un-der the impulse of bad accounting. Although we assist the manipulation of the accounting result, this procedure is done according to the law, been exploited by some entities in knowledge of the lack of justice and accounting regulations.

  6. Agent based models for testing city evacuation strategies under a flood event as strategy to reduce flood risk

    Science.gov (United States)

    Medina, Neiler; Sanchez, Arlex; Nokolic, Igor; Vojinovic, Zoran

    2016-04-01

    This research explores the uses of Agent Based Models (ABM) and its potential to test large scale evacuation strategies in coastal cities at risk from flood events due to extreme hydro-meteorological events with the final purpose of disaster risk reduction by decreasing human's exposure to the hazard. The first part of the paper corresponds to the theory used to build the models such as: Complex adaptive systems (CAS) and the principles and uses of ABM in this field. The first section outlines the pros and cons of using AMB to test city evacuation strategies at medium and large scale. The second part of the paper focuses on the central theory used to build the ABM, specifically the psychological and behavioral model as well as the framework used in this research, specifically the PECS reference model is cover in this section. The last part of this section covers the main attributes or characteristics of human beings used to described the agents. The third part of the paper shows the methodology used to build and implement the ABM model using Repast-Symphony as an open source agent-based modelling and simulation platform. The preliminary results for the first implementation in a region of the island of Sint-Maarten a Dutch Caribbean island are presented and discussed in the fourth section of paper. The results obtained so far, are promising for a further development of the model and its implementation and testing in a full scale city

  7. Application of adversarial risk analysis model in pricing strategies with remanufacturing

    Directory of Open Access Journals (Sweden)

    Liurui Deng

    2015-01-01

    Full Text Available Purpose: Purpose: This paper mainly focus on the application of adversarial risk analysis (ARA in pricing strategy with remanufacturing. We hope to obtain more realistic results than classical model. Moreover, we also wish that our research improve the development of ARA in pricing strategy of manufacturing or remanufacturing. Approach: In order to gain more actual research, combining adversarial risk analysis, we explore the pricing strategy with remanufacturing based on Stackelberg model. Especially, we build OEM’s 1-order ARA model and further study on manufacturers and remanufacturers’ pricing strategy. Findings: We find the OEM’s 1-order ARA model for the OEM’s product cost C. Besides, we get according manufacturers and remanufacturers’ pricing strategies. Besides, the pricing strategies based on 1-order ARA model have advantage over than the classical model regardless of OEMs and remanufacturers. Research implications: The research on application of ARA imply that we can get more actual results with this kind of modern risk analysis method and ARA can be extensively in pricing strategies of supply chain. Value: Our research improves the application of ARA in remanufacturing industry. Meanwhile, inspired by this analysis, we can also create different ARA models for different parameters. Furthermore, some results and analysis methods can be applied to other pricing strategies of supply chain.

  8. A model of extracellular enzymes in free-living microbes: Which strategy pays off?

    DEFF Research Database (Denmark)

    Traving, Sachia J; Thygesen, Uffe Høgsbro; Riemann, Lasse

    2015-01-01

    a slight positive effect for the attached-enzyme strategy, while the effect is negative for the free-enzyme strategy. The results of this study suggest that specific dissolved organic compounds in the ocean likely persist below a threshold concentration impervious to biological utilization. This could help...... must be utilized efficiently. The model revealed that surface-attached and free enzymes generate unique enzyme and substrate fields, and each deployment strategy has distinctive advantages. For a solitary cell, surface-attached enzymes are suggested to be the most cost-efficient strategy. This strategy...

  9. ANALISIS DAN MODEL STRATEGI PENINGKATAN DAYA SAING PRODUK EDAMAME BEKU

    Directory of Open Access Journals (Sweden)

    Sandryas Alief Kurniasanti

    2015-03-01

    Full Text Available Jember regency is a agricultural and plantation central area. The soybean plant is principal commodity that competes fiercely with production of corn. PT Mitratani Dua Tujuh (PT MT 27 try to find new technology by processing edamame to frozen edamame that focus in the export market. The primary market of frozen edamame besides domestic market is Japan. The aim of this research is to analyze competitiveness and formulated the priority of competitiveness alternative strategy on frozen edamame product in PT MT 27. The research method used is the analysis of competitiveness by using revealed comparative advantage to know the export performance of the product on the world market then analyze a factor of competition by using Diamond Porter's Theory. Alternative strategies are resulted from the SWOT analysis and priorities are determined by using analytical hierarchy process from the expert source. The research results about alternative strategy priority to increase the competitiveness of frozen edamame products in PT MT 27 are: (1 market diversification, (2 product diversification, (3 improve cooperation overseas, (4 develop a research and development division, (5 develop corporate social responsibility, (6 proper financial management, and (7 to develop an agricultural area greenhouse-based to avoid bad weather as tropical country. Managerial implications of this research are expanding existing markets, and develop type of product produced to satisfy the export market and also savings cost production. Keywords: competitiveness, frozen edamame, Mitratani Dua Tujuh, competitiveness strategiesABSTRAKKabupaten Jember merupakan sentra  daerah pertanian dan perkebunan. Tanaman kedelai merupakan komoditas utama yang bersaing ketat dengan produksi jagung. PT Mitratani Dua Tujuh (PT MT 27 mencoba untuk mencari terobosan baru yaitu dengan mengolah edamame menjadi edamame beku siap makan. Pasar utama edamame beku ini selain pasar domestik adalah Jepang. Tujuan

  10. Double-multiple streamtube model for studying vertical-axis wind turbines

    Science.gov (United States)

    Paraschivoiu, Ion

    1988-08-01

    This work describes the present state-of-the-art in double-multiple streamtube method for modeling the Darrieus-type vertical-axis wind turbine (VAWT). Comparisons of the analytical results with the other predictions and available experimental data show a good agreement. This method, which incorporates dynamic-stall and secondary effects, can be used for generating a suitable aerodynamic-load model for structural design analysis of the Darrieus rotor.

  11. Analyzing “Etka Chain Stores” Strategies and Proposing Optimal Strategies; Using SWOT Model based on Fuzzy Logic

    OpenAIRE

    Mohammad Aghaei; Amin Asadollahi; Elham Vahedi; Mahdi Pirooz

    2013-01-01

    To maintain and achieve optimal growth, development and to be more competitive, organizations need a comprehensive and coherent plan compatible with their objectives and goals which is called strategic planning. This research aims to analyse strategically “Etka Chain Stores” and to propose optimal strategies by using SWOT model and based on fuzzy logic. The scope of this research is limited to “Etka Chain stores in Tehran”. As instrumentation, a questioner, consisting of 138 questions, was us...

  12. Comparative analysis of turbulence models for flow simulation around a vertical axis wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Roy, S.; Saha, U.K. [Indian Institute of Technology Guwahati, Dept. of Mechanical Engineering, Guwahati (India)

    2012-07-01

    An unsteady computational investigation of the static torque characteristics of a drag based vertical axis wind turbine (VAWT) has been carried out using the finite volume based computational fluid dynamics (CFD) software package Fluent 6.3. A comparative study among the various turbulence models was conducted in order to predict the flow over the turbine at static condition and the results are validated with the available experimental results. CFD simulations were carried out at different turbine angular positions between 0 deg.-360 deg. in steps of 15 deg.. Results have shown that due to high static pressure on the returning blade of the turbine, the net static torque is negative at angular positions of 105 deg.-150 deg.. The realizable k-{epsilon} turbulent model has shown a better simulation capability over the other turbulent models for the analysis of static torque characteristics of the drag based VAWT. (Author)

  13. Model tests of wind turbine with a vertical axis of rotation type Lenz 2

    Science.gov (United States)

    Zwierzchowski, Jaroslaw; Laski, Pawel Andrzej; Blasiak, Slawomir; Takosoglu, Jakub Emanuel; Pietrala, Dawid Sebastian; Bracha, Gabriel Filip; Nowakowski, Lukasz

    A building design of vertical axis wind turbines (VAWT) was presented in the article. The construction and operating principle of a wind turbine were described therein. Two VAWT turbine models were compared, i.a. Darrieus and Lenz2, taking their strengths and weaknesses into consideration. 3D solid models of turbine components were presented with the use of SolidWorks software. Using CFD methods, the air flow on two aerodynamic fins, symmetrical and asymmetrical, at different angles of attack were tested. On the basis of flow simulation conducted in FlowSimulation, an asymmetrical fin was chosen as the one showing greater load bearing capacities. Due to the uncertainty of trouble-free operation of Darrieus turbine on construction elements creating the basis thereof, a 3D model of Lenz2 turbine was constructed, which is more reliable and makes turbine self-start possible. On the basis of the research, components were designed and technical docu mentation was compiled.

  14. System theory and safety models in Swedish, UK, Dutch and Australian road safety strategies.

    Science.gov (United States)

    Hughes, B P; Anund, A; Falkmer, T

    2015-01-01

    Road safety strategies represent interventions on a complex social technical system level. An understanding of a theoretical basis and description is required for strategies to be structured and developed. Road safety strategies are described as systems, but have not been related to the theory, principles and basis by which systems have been developed and analysed. Recently, road safety strategies, which have been employed for many years in different countries, have moved to a 'vision zero', or 'safe system' style. The aim of this study was to analyse the successful Swedish, United Kingdom and Dutch road safety strategies against the older, and newer, Australian road safety strategies, with respect to their foundations in system theory and safety models. Analysis of the strategies against these foundations could indicate potential improvements. The content of four modern cases of road safety strategy was compared against each other, reviewed against scientific systems theory and reviewed against types of safety model. The strategies contained substantial similarities, but were different in terms of fundamental constructs and principles, with limited theoretical basis. The results indicate that the modern strategies do not include essential aspects of systems theory that describe relationships and interdependencies between key components. The description of these strategies as systems is therefore not well founded and deserves further development. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. A descriptive ecosystem model - a strategy for model development during site investigations

    International Nuclear Information System (INIS)

    Loefgren, Anders

    2003-09-01

    This report describes a strategy for the development of a site descriptive model for the surface ecosystem on the potential deep repository sites. The surface ecosystem embraces many disciplines, and these have to be identified, described and integrated in order to construct a descriptive ecosystem model that describes and quantifies biotic and abiotic patterns and processes of importance for the ecosystem on the site. The descriptive model includes both present day conditions and historical information. The descriptive ecosystem model will be used to supply input data for the safety assessment and to serve as the baseline model for devising a monitoring program to detect short-term disturbances caused first by the site investigations and later by the construction of the deep repository. Furthermore, it will serve as a reference for future comparisons to determine more long-term effects or changes caused by the deep repository. The report adopts a non-site-specific approach focusing on the following aims: 1. To present and define the properties that will constitute the descriptive ecosystem model. 2. To present a methodology for determining those properties. 3. To describe and develop the framework for the descriptive ecosystem model by integrating the different properties. 4. To present vital data from other site descriptive models such as those for geology or hydrogeology that interacts with and affects the descriptive ecosystem model. The properties are described under four different sections: general physical properties of the landscape, the terrestrial system, the limnic system and the marine system. These headings are further subdivided into entities that integrate properties in relation to processes

  16. A descriptive ecosystem model - a strategy for model development during site investigations

    Energy Technology Data Exchange (ETDEWEB)

    Loefgren, Anders [Stockholm Univ. (Sweden). Dept. of Botany; Lindborg, Tobias [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

    2003-09-01

    This report describes a strategy for the development of a site descriptive model for the surface ecosystem on the potential deep repository sites. The surface ecosystem embraces many disciplines, and these have to be identified, described and integrated in order to construct a descriptive ecosystem model that describes and quantifies biotic and abiotic patterns and processes of importance for the ecosystem on the site. The descriptive model includes both present day conditions and historical information. The descriptive ecosystem model will be used to supply input data for the safety assessment and to serve as the baseline model for devising a monitoring program to detect short-term disturbances caused first by the site investigations and later by the construction of the deep repository. Furthermore, it will serve as a reference for future comparisons to determine more long-term effects or changes caused by the deep repository. The report adopts a non-site-specific approach focusing on the following aims: 1. To present and define the properties that will constitute the descriptive ecosystem model. 2. To present a methodology for determining those properties. 3. To describe and develop the framework for the descriptive ecosystem model by integrating the different properties. 4. To present vital data from other site descriptive models such as those for geology or hydrogeology that interacts with and affects the descriptive ecosystem model. The properties are described under four different sections: general physical properties of the landscape, the terrestrial system, the limnic system and the marine system. These headings are further subdivided into entities that integrate properties in relation to processes.

  17. A Comparison of Two Strategies for Building an Exposure Prediction Model.

    Science.gov (United States)

    Heiden, Marina; Mathiassen, Svend Erik; Garza, Jennifer; Liv, Per; Wahlström, Jens

    2016-01-01

    Cost-efficient assessments of job exposures in large populations may be obtained from models in which 'true' exposures assessed by expensive measurement methods are estimated from easily accessible and cheap predictors. Typically, the models are built on the basis of a validation study comprising 'true' exposure data as well as an extensive collection of candidate predictors from questionnaires or company data, which cannot all be included in the models due to restrictions in the degrees of freedom available for modeling. In these situations, predictors need to be selected using procedures that can identify the best possible subset of predictors among the candidates. The present study compares two strategies for selecting a set of predictor variables. One strategy relies on stepwise hypothesis testing of associations between predictors and exposure, while the other uses cluster analysis to reduce the number of predictors without relying on empirical information about the measured exposure. Both strategies were applied to the same dataset on biomechanical exposure and candidate predictors among computer users, and they were compared in terms of identified predictors of exposure as well as the resulting model fit using bootstrapped resamples of the original data. The identified predictors were, to a large part, different between the two strategies, and the initial model fit was better for the stepwise testing strategy than for the clustering approach. Internal validation of the models using bootstrap resampling with fixed predictors revealed an equally reduced model fit in resampled datasets for both strategies. However, when predictor selection was incorporated in the validation procedure for the stepwise testing strategy, the model fit was reduced to the extent that both strategies showed similar model fit. Thus, the two strategies would both be expected to perform poorly with respect to predicting biomechanical exposure in other samples of computer users. © The

  18. EVALUASI MODEL STRATEGI PENINGKATAN KINERJA BALAI PENYULUHAN PERTANIAN (BPP) DAN PENGEMBANGAN BPP MODEL (POSLUHDES) DI KABUPATEN MAROS, SULAWESI SELATAN

    OpenAIRE

    Jamil, Muh.Hatta; Tenriawaru, Nixia A; Akhsan Djalaluddin; . Rukka, Rusli M

    2014-01-01

    Evaluasi Model Strategi Peningkatan Kinerja Balai Penyuluhan Pertanian dan Pengembangan BPP Model (Posluhdes) bertujuan mengungkapkan dan menyusun desain evaluasi implementasi model dari modul yang telah diimplementasikan pada penelitian tahap sebelumnya dan diikuti dengan proses transfer pengetahuan dan keterampilan. Melakukan pendampingan pembentukan secara partisipatif BPP Model (Posluhdes) serta mengukur partisipasi petani pada penyuluhan pertanian dan peran penyuluh dalam menjalankan kee...

  19. Strategy-Driven Exploration for Rule-Based Models of Biochemical Systems with Porgy

    OpenAIRE

    Andrei , Oana; Fernández , Maribel; Kirchner , Hélène; Pinaud , Bruno

    2016-01-01

    This paper presents Porgy – an interactive visual environment for rule-based modelling of biochemical systems. We model molecules and molecule interactions as port graphs and port graph rewrite rules, respectively. We use rewriting strategies to control which rules to apply, and where and when to apply them. Our main contributions to rule-based modelling of biochemical systems lie in the strategy language and the associated visual and interactive features offered by Porgy. These features faci...

  20. Using of dynamic strategy model in innovation process

    Directory of Open Access Journals (Sweden)

    Monika Chobotová

    2013-01-01

    Full Text Available This paper incorporates a new scenario method which can use for formulate innovation strategy. The purpose of scenario is not to identify the most likely future, but to create a map of uncertainty — to acknowledge and examine the visible and hidden forces that directed toward the unknown future of a firm. Scenarios are used for capture a range of possibilities, good and bad, expected and surprising. They are designed to stretch our thinking about emerging changes and the opportunities and threats that may occur in the future. Scenario allows us to weigh our choices more carefully when making short-term and long-term strategic decisions.

  1. Designing Multidimensional Policing Strategy And Organization: Towards A Synthesis Of Professional And Community Police Models

    Directory of Open Access Journals (Sweden)

    Suve Priit

    2015-06-01

    Full Text Available In this article we analyse professional police and community policing in view of professionalism, strategy and structures. We aim to find ways for synthesizing these models that are usually seen as incompatible. Unlike many earlier studies of police organizations or strategies, we view strategies in the organization at the corporate, functional and operational levels, and argue that by combining them with functional and divisional principles of structuring, it is possible to place professional strategy at the core of policing, while using the community policing strategy mainly as a component part of the strategy in the framework of divisional organization. This way it is possible to avoid the risk of alienating police from the community and to ensure the successful implementation of corporate strategy through providing professional police units that perform the narrow functions, with quick and adequate information from the community.

  2. Business Model and Strategy Development of Commulus Digital Marketing and COmmunication Indonesia

    OpenAIRE

    Saputra, Arif Fajar; Motik, Suryani Sidik

    2013-01-01

    The findings of this study will help CIDMAC as new venture in digital advertising industry to formulate their business strategy (Especially in the beginning of their business) to be able to compete with existing competitors and capture many opportunities ahead. The authors propose the formulation of CIDMAC's business model and DIAMOND Strategy as outlined in the implementation of business strategies in short term (1 year) and long term (3 years) that are expected to make CIDMAC business conti...

  3. Branded Content: A new Model for driving Tourism via Film and Branding Strategies

    OpenAIRE

    Horrigan, David

    2009-01-01

    Branded content is described as a fusion of advertising and entertainment into one marketing communications product that is integrated into an organisation’s overall brand strategy intended to be distributed as entertainment content with a highly branded quality. A history of product placement, branded entertainment, and film tourism is presented to identify the effective elements of each strategy in order to inform a more cohesive brand strategy for destinations. A branded content model is...

  4. Company Strategies for Responsible Research and Innovation (RRI): A Conceptual Model

    OpenAIRE

    Klaassen, P.; van de Poel, Ibo; Asveld, Lotte; Flipse, Steven; Scholten, Victor; Yaghmaei, Emad

    2017-01-01

    Responsible research and innovation (RRI) has become an important topic in the academic community and in policy circles, but it has not yet been systematically included in the innovation process of companies. We discuss how companies can integrate RRI into their corporate social responsibility (CSR) policies and business strategy. To this end, we developed a conceptual model that links a company’s RRI strategy to its context, and that helps to translate the RRI strategy into activities that r...

  5. Company strategies for responsible research and innovation (RRI): A conceptual model

    OpenAIRE

    van de Poel, I.R.; Asveld, L.; Flipse, S.M.; Klaassen, Pim; Scholten, V.E.; Yaghmaei, E.

    2017-01-01

    Responsible research and innovation (RRI) has become an important topic in the academic community and in policy circles, but it has not yet been systematically included in the innovation process of companies. We discuss how companies can integrate RRI into their corporate social responsibility (CSR) policies and business strategy. To this end, we developed a conceptual model that links a company's RRI strategy to its context, and that helps to translate the RRI strategy into activities that r...

  6. Evaluation of Cost Leadership Strategy in Shipping Enterprises with Simulation Model

    Science.gov (United States)

    Ferfeli, Maria V.; Vaxevanou, Anthi Z.; Damianos, Sakas P.

    2009-08-01

    The present study will attempt the evaluation of cost leadership strategy that prevails in certain shipping enterprises and the creation of simulation models based on strategic model STAIR. The above model is an alternative method of strategic applications evaluation. This is held in order to be realised if the strategy of cost leadership creates competitive advantage [1] and this will be achieved via the technical simulation which appreciates the interactions between the operations of an enterprise and the decision-making strategy in conditions of uncertainty with reduction of undertaken risk.

  7. Acquiring, Representing, and Evaluating a Competence Model of Diagnostic Strategy.

    Science.gov (United States)

    Clancey, William J.

    This paper describes NEOMYCIN, a computer program that models one physician's diagnostic reasoning within a limited area of medicine. NEOMYCIN's knowledge base and reasoning procedure constitute a model of how human knowledge is organized and how it is used in diagnosis. The hypothesis is tested that such a procedure can be used to simulate both…

  8. Simulation of electric power conservation strategies: model of economic evaluation

    International Nuclear Information System (INIS)

    Pinhel, A.C.C.

    1992-01-01

    A methodology for the economic evaluation model for energy conservation programs to be executed by the National Program of Electric Power Conservation is presented. From data as: forecasting of conserved energy, tariffs, energy costs and budget, the model calculates the economic indexes for the programs, allowing the evaluation of economic impacts in the electric sector. (C.G.C.)

  9. Cost modelling in maintenance strategy optimisation for infrastructure assets with limited data

    International Nuclear Information System (INIS)

    Zhang, Wenjuan; Wang, Wenbin

    2014-01-01

    Our paper reports on the use of cost modelling in maintenance strategy optimisation for infrastructure assets. We present an original approach: the possibility of modelling even when the data and information usually required are not sufficient in quantity and quality. Our method makes use of subjective expert knowledge, and requires information gathered for only a small sample of assets to start with. Bayes linear methods are adopted to combine the subjective expert knowledge with the sample data to estimate the unknown model parameters of the cost model. When new information becomes available, Bayes linear methods also prove useful in updating these estimates. We use a case study from the rail industry to demonstrate our methods. The optimal maintenance strategy is obtained via simulation based on the estimated model parameters and the strategy with the least unit time cost is identified. When the optimal strategy is not followed due to insufficient funding, the future costs of recovering the degraded asset condition are estimated

  10. Search strategies for top partners in composite Higgs models

    Science.gov (United States)

    Gripaios, Ben; Müller, Thibaut; Parker, M. A.; Sutherland, Dave

    2014-08-01

    We consider how best to search for top partners in generic composite Higgs models. We begin by classifying the possible group representations carried by top partners in models with and without a custodial SU(2) × SU(2) ⋊ 2 symmetry protecting the rate for Z → decays. We identify a number of minimal models whose top partners only have electric charges of , , or and thus decay to top or bottom quarks via a single Higgs or electroweak gauge boson. We develop an inclusive search for these based on a top veto, which we find to be more effective than existing searches. Less minimal models feature light states that can be sought in final states with like-sign leptons and so we find that 2 straightforward LHC searches give a reasonable coverage of the gamut of composite Higgs models.

  11. Thermal site descriptive model. A strategy for the model development during site investigations - version 2

    Energy Technology Data Exchange (ETDEWEB)

    Back, Paer-Erik; Sundberg, Jan [Geo Innova AB (Sweden)

    2007-09-15

    This report presents a strategy for describing, predicting and visualising the thermal aspects of the site descriptive model. The strategy is an updated version of an earlier strategy applied in all SDM versions during the initial site investigation phase at the Forsmark and Oskarshamn areas. The previous methodology for thermal modelling did not take the spatial correlation fully into account during simulation. The result was that the variability of thermal conductivity in the rock mass was not sufficiently well described. Experience from earlier thermal SDMs indicated that development of the methodology was required in order describe the spatial distribution of thermal conductivity in the rock mass in a sufficiently reliable way, taking both variability within rock types and between rock types into account. A good description of the thermal conductivity distribution is especially important for the lower tail. This tail is important for the design of a repository because it affects the canister spacing. The presented approach is developed to be used for final SDM regarding thermal properties, primarily thermal conductivity. Specific objectives for the strategy of thermal stochastic modelling are: Description: statistical description of the thermal conductivity of a rock domain. Prediction: prediction of thermal conductivity in a specific rock volume. Visualisation: visualisation of the spatial distribution of thermal conductivity. The thermal site descriptive model should include the temperature distribution and thermal properties of the rock mass. The temperature is the result of the thermal processes in the repository area. Determination of thermal transport properties can be made using different methods, such as laboratory investigations, field measurements, modelling from mineralogical composition and distribution, modelling from density logging and modelling from temperature logging. The different types of data represent different scales, which has to be

  12. Thermal site descriptive model. A strategy for the model development during site investigations - version 2

    International Nuclear Information System (INIS)

    Back, Paer-Erik; Sundberg, Jan

    2007-09-01

    This report presents a strategy for describing, predicting and visualising the thermal aspects of the site descriptive model. The strategy is an updated version of an earlier strategy applied in all SDM versions during the initial site investigation phase at the Forsmark and Oskarshamn areas. The previous methodology for thermal modelling did not take the spatial correlation fully into account during simulation. The result was that the variability of thermal conductivity in the rock mass was not sufficiently well described. Experience from earlier thermal SDMs indicated that development of the methodology was required in order describe the spatial distribution of thermal conductivity in the rock mass in a sufficiently reliable way, taking both variability within rock types and between rock types into account. A good description of the thermal conductivity distribution is especially important for the lower tail. This tail is important for the design of a repository because it affects the canister spacing. The presented approach is developed to be used for final SDM regarding thermal properties, primarily thermal conductivity. Specific objectives for the strategy of thermal stochastic modelling are: Description: statistical description of the thermal conductivity of a rock domain. Prediction: prediction of thermal conductivity in a specific rock volume. Visualisation: visualisation of the spatial distribution of thermal conductivity. The thermal site descriptive model should include the temperature distribution and thermal properties of the rock mass. The temperature is the result of the thermal processes in the repository area. Determination of thermal transport properties can be made using different methods, such as laboratory investigations, field measurements, modelling from mineralogical composition and distribution, modelling from density logging and modelling from temperature logging. The different types of data represent different scales, which has to be

  13. New modelling strategy for IRIS dynamic response simulation

    International Nuclear Information System (INIS)

    Cammi, A.; Ricotti, M. E.; Casella, F.; Schiavo, F.

    2004-01-01

    The pressurized light water cooled, medium power (1000 MWt) IRIS (International Reactor Innovative and Secure) has been under development for four years by an international consortium of over 21 organizations from ten countries. The plant conceptual design was completed in 2001 and the preliminary design is nearing completion. The pre-application licensing process with NRC started in October, 2002 and IRIS is one of the designs considered by US utilities as part of the ESP (Early Site Permit) process. In this paper the development of an adequate modeling and simulation tool for Dynamics and Control tasks is presented. The key features of the developed simulator are: a) Modularity: the system model is built by connecting the models of its components, which are written independently of their boundary conditions; b) Openness: the code of each component model is clearly readable and close to the original equations and easily customised by the experienced user; c) Efficiency: the simulation code is fast; d) Tool support: the simulation tool is based on reliable, tested and well-documented software. To achieve these objectives, the Modelica language was used as a basis for the development of the simulator. The Modelica language is the results of recent advances in the field of object-oriented, multi-physics, dynamic system modelling. The language definition is open-source and it has already been successfully adopted in several industrial fields. To provide the required capabilities for the analysis, specific models for nuclear reactor components have been developed, to be applied for the dynamic simulation of the IRIS integral reactor, albeit keeping general validity for PWR plants. The following Modelica models have been written to satisfy the IRIS modelling requirements and are presented in this paper: neutronics point kinetic, fuel heat transfer, control rods model, including the innovative internal drive mechanism type, and a once-through type steam generator, thus

  14. Learning reliable manipulation strategies without initial physical models

    Science.gov (United States)

    Christiansen, Alan D.; Mason, Matthew T.; Mitchell, Tom M.

    1990-01-01

    A description is given of a robot, possessing limited sensory and effectory capabilities but no initial model of the effects of its actions on the world, that acquires such a model through exploration, practice, and observation. By acquiring an increasingly correct model of its actions, it generates increasingly successful plans to achieve its goals. In an apparently nondeterministic world, achieving reliability requires the identification of reliable actions and a preference for using such actions. Furthermore, by selecting its training actions carefully, the robot can significantly improve its learning rate.

  15. Toward a Tripartite Model of L2 Reading Strategy Use, Motivations, and Learner Beliefs

    Science.gov (United States)

    Matsumoto, Hiroyuki; Hiromori, Tomohito; Nakayama, Akira

    2013-01-01

    The present study proposes a tripartite model of L2 reading strategy use, reading motivations, and general learner beliefs by examining the relationships among them in an L2 context. Reading strategy instruction was performed for 360 first-year university students enrolled in a reading-based course, in expectation of affecting their motivations…

  16. The match-mismatch model of emotion processing styles and emotion regulation strategies in fibromyalgia.

    NARCIS (Netherlands)

    Geenen, R.; Ooijen-van der Linden, L. van; Lumley, M.A.; Bijlsma, J.W.J.; Middendorp, H. van

    2012-01-01

    OBJECTIVE: Individuals differ in their style of processing emotions (e.g., experiencing affects intensely or being alexithymic) and their strategy of regulating emotions (e.g., expressing or reappraising). A match-mismatch model of emotion processing styles and emotion regulation strategies is

  17. Model Drawing Strategy for Fraction Word Problem Solving of Fourth-Grade Students with Learning Disabilities

    Science.gov (United States)

    Sharp, Emily; Shih Dennis, Minyi

    2017-01-01

    This study used a multiple probe across participants design to examine the effects of a model drawing strategy (MDS) intervention package on fraction comparing and ordering word problem-solving performance of three Grade 4 students. MDS is a form of cognitive strategy instruction for teaching word problem solving that includes explicit instruction…

  18. Mental Model Progression in Learning the Electron Transport Chain: Effects of Instructional Strategies and Cognitive Flexibility

    Science.gov (United States)

    Darabi, Aubteen; Hemphill, Jennifer; Nelson, David W.; Boulware, Wilma; Liang, Xinya

    2010-01-01

    This study investigated the effect of two instructional strategies, segmented and holistic, on the progression over time of learners' mental models toward that of an expert with the moderator of cognitive flexibility. Sixty-four juniors and seniors in a college metabolism course were randomly assigned to one of the two strategies for instruction…

  19. The Relationship between the Big-Five Model of Personality and Self-Regulated Learning Strategies

    Science.gov (United States)

    Bidjerano, Temi; Dai, David Yun

    2007-01-01

    The study examined the relationship between the big-five model of personality and the use of self-regulated learning strategies. Measures of self-regulated learning strategies and big-five personality traits were administered to a sample of undergraduate students. Results from canonical correlation analysis indicated an overlap between the…

  20. Reconstructing Holocene climate using a climate model: Model strategy and preliminary results

    Science.gov (United States)

    Haberkorn, K.; Blender, R.; Lunkeit, F.; Fraedrich, K.

    2009-04-01

    An Earth system model of intermediate complexity (Planet Simulator; PlaSim) is used to reconstruct Holocene climate based on proxy data. The Planet Simulator is a user friendly general circulation model (GCM) suitable for palaeoclimate research. Its easy handling and the modular structure allow for fast and problem dependent simulations. The spectral model is based on the moist primitive equations conserving momentum, mass, energy and moisture. Besides the atmospheric part, a mixed layer-ocean with sea ice and a land surface with biosphere are included. The present-day climate of PlaSim, based on an AMIP II control-run (T21/10L resolution), shows reasonable agreement with ERA-40 reanalysis data. Combining PlaSim with a socio-technological model (GLUES; DFG priority project INTERDYNAMIK) provides improved knowledge on the shift from hunting-gathering to agropastoral subsistence societies. This is achieved by a data assimilation approach, incorporating proxy time series into PlaSim to initialize palaeoclimate simulations during the Holocene. For this, the following strategy is applied: The sensitivities of the terrestrial PlaSim climate are determined with respect to sea surface temperature (SST) anomalies. Here, the focus is the impact of regionally varying SST both in the tropics and the Northern Hemisphere mid-latitudes. The inverse of these sensitivities is used to determine the SST conditions necessary for the nudging of land and coastal proxy climates. Preliminary results indicate the potential, the uncertainty and the limitations of the method.

  1. Optimum investment strategy in the power industry mathematical models

    CERN Document Server

    Bartnik, Ryszard; Hnydiuk-Stefan, Anna

    2016-01-01

    This book presents an innovative methodology for identifying optimum investment strategies in the power industry. To do so, it examines results including, among others, the impact of oxy-fuel technology on CO2 emissions prices, and the specific cost of electricity production. The technical and economic analysis presented here extend the available knowledge in the field of investment optimization in energy engineering, while also enabling investors to make decisions involving its application. Individual chapters explore the potential impacts of different factors like environmental charges on costs connected with investments in the power sector, as well as discussing the available technologies for heat and power generation. The book offers a valuable resource for researchers, market analysts, decision makers, power engineers and students alike.

  2. Chaos control in an economic model via minimum entropy strategy

    Energy Technology Data Exchange (ETDEWEB)

    Salarieh, Hassan [Center of Excellence in Design, Robotics and Automation, Department of Mechanical Engineering, Sharif University of Technology, P.O. Box 11365-9567, Tehran (Iran, Islamic Republic of)], E-mail: salarieh@mech.sharif.edu; Alasty, Aria [Center of Excellence in Design, Robotics and Automation, Department of Mechanical Engineering, Sharif University of Technology, P.O. Box 11365-9567, Tehran (Iran, Islamic Republic of); National Research Institute for Science Policy (NRISP), Soheil Street, Shirazi Avenue, Tehran (Iran, Islamic Republic of)], E-mail: aalasti@sharif.edu

    2009-04-30

    In this paper, minimum entropy algorithm for controlling chaos, is applied to a Cournot duopoly with different constant marginal costs, as a discrete-time dynamical system which shows chaotic behavior. The ME control is implemented through delayed feedback. It is assumed that the equations of the dynamical system are not known, so the feedback gain cannot be obtained analytically from the system equations. In the ME method the feedback gain is obtained adaptively in such a way that the entropy of the system converges to zero, hence a fixed point of the system will be stabilized. Application of the proposed method with different economic control strategies is numerically investigated. Simulation results show the effectiveness of the ME method for controlling chaos in economic systems with unknown equations.

  3. Probabilistic models for access strategies to dynamic information elements

    DEFF Research Database (Denmark)

    Hansen, Martin Bøgsted; Olsen, Rasmus L.; Schwefel, Hans-Peter

    In various network services (e.g., routing and instances of context-sensitive networking) remote access to dynamically changing information elements is a required functionality. Three fundamentally different strategies for such access are investigated in this paper: (1) a reactive approach...... initiated by the requesting entity, and two versions of proactive approaches in which the entity that contains the information element actively propagates its changes to potential requesters, either (2) periodically or (3) triggered by changes of the information element. This paper develops probabilistic...... for information elements spread over a large number of network nodes are provided, which allow to draw conclusions on scalability properties. The impact of different distribution types for the network delays as well as for the time between changes of the information element on the mismatch probability...

  4. Document and author promotion strategies in the secure wiki model

    DEFF Research Database (Denmark)

    Lindberg, Kasper; Jensen, Christian D.

    2012-01-01

    Wiki systems form a subclass of the more general Open Collaborative Authoring Systems, where content is created by a user community. The ability of anyone to edit the content is, at the same time, their strength and their weakness. Anyone can write documents that improve the value of the wiki-system......, but this also means that anyone can introduce errors into documents, either by accident or on purpose. A security model for wiki-style authoring systems, called the Secure Wiki Model, has previously been proposed to address this problem. This model is designed to prevent corruption of good quality documents......, by limiting updates, to such documents, to users who have demonstrated their ability to produce documents of similar or better quality. While this security model prevents all user from editing all documents, it does respect the wiki philosophy by allowing any author who has produced documents of a certain...

  5. Multi-scale modeling strategies in materials science—The ...

    Indian Academy of Sciences (India)

    Unknown

    Multi-scale models; quasicontinuum method; finite elements. 1. Introduction ... boundary with external stresses, and the interaction of a lattice dislocation with a grain ..... mum value of se over the elements that touch node α. The acceleration of ...

  6. An Hourly Streamflow Forecasting Model Coupled with an Enforced Learning Strategy

    Directory of Open Access Journals (Sweden)

    Ming-Chang Wu

    2015-10-01

    Full Text Available Floods, one of the most significant natural hazards, often result in loss of life and property. Accurate hourly streamflow forecasting is always a key issue in hydrology for flood hazard mitigation. To improve the performance of hourly streamflow forecasting, a methodology concerning the development of neural network (NN based models with an enforced learning strategy is proposed in this paper. Firstly, four different NNs, namely back propagation network (BPN, radial basis function network (RBFN, self-organizing map (SOM, and support vector machine (SVM, are used to construct streamflow forecasting models. Through the cross-validation test, NN-based models with superior performance in streamflow forecasting are detected. Then, an enforced learning strategy is developed to further improve the performance of the superior NN-based models, i.e., SOM and SVM in this study. Finally, the proposed flow forecasting model is obtained. Actual applications are conducted to demonstrate the potential of the proposed model. Moreover, comparison between the NN-based models with and without the enforced learning strategy is performed to evaluate the effect of the enforced learning strategy on model performance. The results indicate that the NN-based models with the enforced learning strategy indeed improve the accuracy of hourly streamflow forecasting. Hence, the presented methodology is expected to be helpful for developing improved NN-based streamflow forecasting models.

  7. Energy Exascale Earth System Model (E3SM) Project Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Bader, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-18

    The E3SM project will assert and maintain an international scientific leadership position in the development of Earth system and climate models at the leading edge of scientific knowledge and computational capabilities. With its collaborators, it will demonstrate its leadership by using these models to achieve the goal of designing, executing, and analyzing climate and Earth system simulations that address the most critical scientific questions for the nation and DOE.

  8. Strategies for Excellence: Recommendations for a Productive School Model with Strategies for Achieving the Model. The Final Report of the IASB Committee on Strategies for Excellence.

    Science.gov (United States)

    Iowa Association of School Boards, Des Moines.

    The charge of the Committee on Strategies for Excellence was to examine the current status of elementary and secondary education in Iowa, and to investigate ways in which school districts could be educationally more productive. The report brings together recommendations from various state and national reports, reviews the literature, and makes…

  9. KEEFEKTIFAN STRATEGI MODELING PARTISIPAN DALAM BANTUAN TEMAN SEBAYA (PEER HELPING UNTUK MENINGKATKAN KOMUNIKASI INTERPERSONAL SISWA SMA

    Directory of Open Access Journals (Sweden)

    Zeti Novitasari

    2017-03-01

    Full Text Available Interpersonal communication is one of important skills that should be owned by a student to reach success in the future. Thus, it is needed a proper strategy to improve students interpersonal communication.this study aims at knowing the effectivity 0f participant modelling strategy and covert modelling implemented in peer helping to improve interpersonal communication of senior high students. This study uses pretest and posttest control group design. Participant modeling strategy as experimental group and covert modeling as control group. Every experimental group and control group consist of six students who have low interpersonal communication. The instruments used are interpersonal communication scale, instruction of peer helping by using participant modelling strategy and covert modeling, reflexion sheet, and observation sheet. This study uses two kinds analysis, namely non parametric statistic test, two-independent sample Test-Mann-Whitney U and Wilcoxon test, an analysis to know the changing of each group. The result of study shows participant modeling strategy could improve students interpersonal communication. Komunikasi interpersonal merupakan salah satu ketrampilan yang sangat penting dimiliki oleh seorang pelajar untuk mencapai keberhasilan dalam aktivitas masa depan. Hal tersebut menyebabkan perlu strategi yang tepat untuk meningkatkan komunikasi interpersonal siswa. Tujuan penelitian ini adalah untuk mengetahui keefektifan strategi modeling partisipan dan covert modeling yang diimplementasi dalam bantuan teman sebaya untuk meningkatkan komunikasi interpersonal siswa SMA. Penelitian ini menggunakan rancangan adalah pretest and posttest control group design. Strategi modeling partisipan sebagai kelompok eksperimen dan covert modeling sebagai kelompok control. Setiap kelompok eksperimen dan control terdiri dari enam siswa yang terjaring memiliki komunikasi interpersonal rendah. Instrument yang digunakan adalah skala komunikasi

  10. Model-based optimization strategy of chiller driven liquid desiccant dehumidifier with genetic algorithm

    International Nuclear Information System (INIS)

    Wang, Xinli; Cai, Wenjian; Lu, Jiangang; Sun, Youxian; Zhao, Lei

    2015-01-01

    This study presents a model-based optimization strategy for an actual chiller driven dehumidifier of liquid desiccant dehumidification system operating with lithium chloride solution. By analyzing the characteristics of the components, energy predictive models for the components in the dehumidifier are developed. To minimize the energy usage while maintaining the outlet air conditions at the pre-specified set-points, an optimization problem is formulated with an objective function, the constraints of mechanical limitations and components interactions. Model-based optimization strategy using genetic algorithm is proposed to obtain the optimal set-points for desiccant solution temperature and flow rate, to minimize the energy usage in the dehumidifier. Experimental studies on an actual system are carried out to compare energy consumption between the proposed optimization and the conventional strategies. The results demonstrate that energy consumption using the proposed optimization strategy can be reduced by 12.2% in the dehumidifier operation. - Highlights: • Present a model-based optimization strategy for energy saving in LDDS. • Energy predictive models for components in dehumidifier are developed. • The Optimization strategy are applied and tested in an actual LDDS. • Optimization strategy can achieve energy savings by 12% during operation

  11. Models for solid oxide fuel cell systems exploitation of models hierarchy for industrial design of control and diagnosis strategies

    CERN Document Server

    Marra, Dario; Polverino, Pierpaolo; Sorrentino, Marco

    2016-01-01

    This book presents methodologies for optimal design of control and diagnosis strategies for Solid Oxide Fuel Cell systems. A key feature of the methodologies presented is the exploitation of modelling tools that balance accuracy and computational burden.

  12. A simulation model to estimate the cost and effectiveness of alternative dialysis initiation strategies.

    Science.gov (United States)

    Lee, Chris P; Chertow, Glenn M; Zenios, Stefanos A

    2006-01-01

    Patients with end-stage renal disease (ESRD) require dialysis to maintain survival. The optimal timing of dialysis initiation in terms of cost-effectiveness has not been established. We developed a simulation model of individuals progressing towards ESRD and requiring dialysis. It can be used to analyze dialysis strategies and scenarios. It was embedded in an optimization frame worked to derive improved strategies. Actual (historical) and simulated survival curves and hospitalization rates were virtually indistinguishable. The model overestimated transplantation costs (10%) but it was related to confounding by Medicare coverage. To assess the model's robustness, we examined several dialysis strategies while input parameters were perturbed. Under all 38 scenarios, relative rankings remained unchanged. An improved policy for a hypothetical patient was derived using an optimization algorithm. The model produces reliable results and is robust. It enables the cost-effectiveness analysis of dialysis strategies.

  13. Model-based comparison of strategies for reduction of stormwater micropollutant emissions

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Sharma, Anitha Kumari; Mikkelsen, Peter Steen

    to improve the recipient quality by reducing the fluxes of heavy metals (copper, zinc) and organic compounds (fluoranthene) to natural waters. MP sources were identified by using GIS land usage data. When comparing the different control strategies, the integrated model showed the greater benefits......Strategies for reduction of micropollutant (MP) emissions from stormwater systems require the comparison of different scenarios including source control, end-of-pipe treatment, or their combination. Dynamic integrated models can be important tools for this comparison, as they can integrate...... the limited data provided by monitoring campaigns and evaluate the performance of different strategies based on model simulation results. This study presents an example where an integrated dynamic model, in combination with stormwater quality measurements, was used to evaluate 6 different strategies...

  14. Assessment of local models and tools for analyzing smart-growth strategies.

    Science.gov (United States)

    2007-07-01

    There is a growing interest in California in smart-growth land- use and transportation : strategies designed to provide mobility options and reduce demand on automobile-oriented facilities. This study focuses on models and tools available for u...

  15. Optimal Portfolios in Wishart Models and Effects of Discrete Rebalancing on Portfolio Distribution and Strategy Selection

    OpenAIRE

    Li, Zejing

    2012-01-01

    This dissertation is mainly devoted to the research of two problems - the continuous-time portfolio optimization in different Wishart models and the effects of discrete rebalancing on portfolio wealth distribution and optimal portfolio strategy.

  16. Strategies for the Curation of CAD Engineering Models

    Directory of Open Access Journals (Sweden)

    Manjula Patel

    2009-06-01

    Full Text Available Normal 0 Product Lifecycle Management (PLM has become increasingly important in the engineering community over the last decade or so, due to the globalisation of markets and the rising popularity of products provided as services. It demands the efficient capture, representation, organisation, retrieval and reuse of product data over its entire life. Simultaneously, there is now a much greater reliance on CAD models for communicating designs to manufacturers, builders, maintenance crews and regulators, and for definitively expressing designs. Creating the engineering record digitally, however, presents problems not only for its long-term maintenance and accessibility - due in part to the rapid obsolescence of the hardware, software and file formats involved - but also for recording the evolution of designs, artefacts and products. We examine the curation and preservation requirements in PLM and suggest ways of alleviating the problems of sustaining CAD engineering models through the use of lightweight formats, layered annotation and the collection of Representation Information as defined in the Open Archival Information System (OAIS Reference Model.  We describe two tools which have been specifically developed to aid in the curation of CAD engineering models in the context of PLM: Lightweight Models with Multilayered Annotation (LiMMA and a Registry/Repository of Representation Information for Engineering (RRoRIfE.

  17. Modelling the regional application of stakeholder identified land management strategies.

    Science.gov (United States)

    Irvine, B. J.; Fleskens, L.; Kirkby, M. J.

    2012-04-01

    The DESIRE project has trialled a series of sustainable land management (SLM) technologies. These technologies have been identified as being beneficial in mitigating land degradation by local stakeholders from a range of semi-arid study sites. The field results and the qualitative WOCAT technology assessment ftom across the study sites have been used to develop the adapted PESERA SLM model. This paper considers the development of the adapted PESERA SLM model and the potential for applying locally successful SLM technologies across a wider range of climatic and environmental conditions with respect to degradation risk, biomass production and the investment cost interface (PESERA/DESMICE). The integrate PESERA/DESMICE model contributes to the policy debate by providing a biophysical and socio-economic assessment of technology and policy scenarios.

  18. Ecological models for regulatory risk assessments of pesticides: Developing a strategy for the future.

    NARCIS (Netherlands)

    Thorbek, P.; Forbes, V.; Heimbach, F.; Hommen, U.; Thulke, H.H.; Brink, van den P.J.

    2010-01-01

    Ecological Models for Regulatory Risk Assessments of Pesticides: Developing a Strategy for the Future provides a coherent, science-based view on ecological modeling for regulatory risk assessments. It discusses the benefits of modeling in the context of registrations, identifies the obstacles that

  19. Customer orientation on online newspaper business models with paid content strategies: An empirical study

    OpenAIRE

    Goyanes, Manuel; Sylvie, George

    2014-01-01

    This study examines the transformations that trigger business models with paid content strategies on news organizations under the theoretical framework of market orientation. The results show three main factors: those related to competence, to the organization culture and to understanding of needs and wants of the audience. The findings also suggest that online newspapers business models with paid content strategies are more like experiments or forays rather than definitive methods that monet...

  20. Solid-state-drives (SSDs) modeling simulation tools & strategies

    CERN Document Server

    2017-01-01

    This book introduces simulation tools and strategies for complex systems of solid-state-drives (SSDs) which consist of a flash multi-core microcontroller plus NAND flash memories. It provides a broad overview of the most popular simulation tools, with special focus on open source solutions. VSSIM, NANDFlashSim and DiskSim are benchmarked against performances of real SSDs under different traffic workloads. PROs and CONs of each simulator are analyzed, and it is clearly indicated which kind of answers each of them can give and at a what price. It is explained, that speed and precision do not go hand in hand, and it is important to understand when to simulate what, and with which tool. Being able to simulate SSD’s performances is mandatory to meet time-to-market, together with product cost and quality. Over the last few years the authors developed an advanced simulator named “SSDExplorer” which has been used to evaluate multiple phenomena with great accuracy, from QoS (Quality Of Service) to Read Retry, fr...

  1. Painter and scribe: From model of mind to cognitive strategy.

    Science.gov (United States)

    MacKisack, Matthew

    2017-12-06

    Since antiquity the mind has been conceived to operate via images and words. Pre-scientific thinkers (and some scientific) who presented the mind as operating in such a way tended to i) bias one representational mode over the other, and ii) claim the dominance of the mode to be the case universally. The rise of empirical psychological science in the late 19th-century rehearses the word/image division of thought but makes universal statements - e.g., that recollection is a verbal process for everyone - untenable. Since then, the investigation of individual differences and case studies of imagery loss have shown rather that words and images present alternative cognitive "strategies" that individuals will be predisposed to employing - but which, should the necessity arise, can be relearned using the other representational mode. The following sketches out this historical shift in understanding, and concludes by inviting consideration of the wider context in which discussion of the relationships between 'images' and 'words' (as both internal and external forms of representation) must take place. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Models and strategies for electricity distribution companies in emerging economies

    Science.gov (United States)

    Zaragocin Espinosa, Leonardo Vicente

    Unbundling and privatization have become key elements of restructuring in the Electric Power Industry of Emerging Economies. These processes have concentrated on the Generation and Transmission areas, leaving Distribution as lower priority. Based on a comparison between the old role of Distribution Companies (DISCOS) and its new potential role this study identifies the main issues and challenges that DISCOS will face in the new environment once structural and ownership changes are completed. For the specific case of DISCOS in Emerging Economies, regulatory policies are reviewed and strategies identified in order to facilitate the transition and to assist in the integration of DISCOS with other agents in the evolving electric power market. Of particular importance in this research is the analysis of the role of Energy Efficiency (EE) in the new structural and governance environment. A theoretical study of the effects of energy efficiency measures, specifically loss reduction, on price regulation is developed within a proposed regulatory regime of privatization together with Price-Cap Regulation. This theoretical benchmark is then used as a starting point for a case study, the Electric System of Ecuador, where an analysis of the current Ecuadorian price regulation scheme (the Distribution Value Added Charge, VAD, scheme) is presented and analyzed in detail. General recommendations for improving the application of the VAD pricing approach are advanced, with special reference to the current situation in Ecuador.

  3. Retrieval and organizational strategies in conceptual memory a computer model

    CERN Document Server

    Kolodner, Janet L

    2014-01-01

    'Someday we expect that computers will be able to keep us informed about the news. People have imagined being able to ask their home computers questions such as "What's going on in the world?"…'. Originally published in 1984, this book is a fascinating look at the world of memory and computers before the internet became the mainstream phenomenon it is today. It looks at the early development of a computer system that could keep us informed in a way that we now take for granted. Presenting a theory of remembering, based on human information processing, it begins to address many of the hard problems implicated in the quest to make computers remember. The book had two purposes in presenting this theory of remembering. First, to be used in implementing intelligent computer systems, including fact retrieval systems and intelligent systems in general. Any intelligent program needs to use and store and use a great deal of knowledge. The strategies and structures in the book were designed to be used for that purpos...

  4. A literature review on growth models and strategies: The missing link in entrepreneurial growth

    Directory of Open Access Journals (Sweden)

    Syed Fida Hussain Shah

    2013-08-01

    Full Text Available This study focuses on the importance of growth models, growth strategies, role of knowledge management system in the formulation of effective strategy for the enterprises following growth. Choice of an appropriate growth strategy is at the heart of any successful entrepreneurial venture. Selection of a strategy may be effective for one entrepreneur while it is not for other. Choice of Growth Strategy depends on various different factors, organisational context and environment which may vary from enterprise to enterprise. Resource based view is very important consideration for the entrepreneurs on the path of growth. Evaluation of all kind of resources helps them to grow their enterprises successfully. Selection of an appropriate growth strategy allows the entrepreneurs in overcoming growth challenges and avoiding the growth reversals and setbacks.

  5. Sensitivity analysis practices: Strategies for model-based inference

    International Nuclear Information System (INIS)

    Saltelli, Andrea; Ratto, Marco; Tarantola, Stefano; Campolongo, Francesca

    2006-01-01

    Fourteen years after Science's review of sensitivity analysis (SA) methods in 1989 (System analysis at molecular scale, by H. Rabitz) we search Science Online to identify and then review all recent articles having 'sensitivity analysis' as a keyword. In spite of the considerable developments which have taken place in this discipline, of the good practices which have emerged, and of existing guidelines for SA issued on both sides of the Atlantic, we could not find in our review other than very primitive SA tools, based on 'one-factor-at-a-time' (OAT) approaches. In the context of model corroboration or falsification, we demonstrate that this use of OAT methods is illicit and unjustified, unless the model under analysis is proved to be linear. We show that available good practices, such as variance based measures and others, are able to overcome OAT shortcomings and easy to implement. These methods also allow the concept of factors importance to be defined rigorously, thus making the factors importance ranking univocal. We analyse the requirements of SA in the context of modelling, and present best available practices on the basis of an elementary model. We also point the reader to available recipes for a rigorous SA

  6. Sensitivity analysis practices: Strategies for model-based inference

    Energy Technology Data Exchange (ETDEWEB)

    Saltelli, Andrea [Institute for the Protection and Security of the Citizen (IPSC), European Commission, Joint Research Centre, TP 361, 21020 Ispra (Vatican City State, Holy See,) (Italy)]. E-mail: andrea.saltelli@jrc.it; Ratto, Marco [Institute for the Protection and Security of the Citizen (IPSC), European Commission, Joint Research Centre, TP 361, 21020 Ispra (VA) (Italy); Tarantola, Stefano [Institute for the Protection and Security of the Citizen (IPSC), European Commission, Joint Research Centre, TP 361, 21020 Ispra (VA) (Italy); Campolongo, Francesca [Institute for the Protection and Security of the Citizen (IPSC), European Commission, Joint Research Centre, TP 361, 21020 Ispra (VA) (Italy)

    2006-10-15

    Fourteen years after Science's review of sensitivity analysis (SA) methods in 1989 (System analysis at molecular scale, by H. Rabitz) we search Science Online to identify and then review all recent articles having 'sensitivity analysis' as a keyword. In spite of the considerable developments which have taken place in this discipline, of the good practices which have emerged, and of existing guidelines for SA issued on both sides of the Atlantic, we could not find in our review other than very primitive SA tools, based on 'one-factor-at-a-time' (OAT) approaches. In the context of model corroboration or falsification, we demonstrate that this use of OAT methods is illicit and unjustified, unless the model under analysis is proved to be linear. We show that available good practices, such as variance based measures and others, are able to overcome OAT shortcomings and easy to implement. These methods also allow the concept of factors importance to be defined rigorously, thus making the factors importance ranking univocal. We analyse the requirements of SA in the context of modelling, and present best available practices on the basis of an elementary model. We also point the reader to available recipes for a rigorous SA.

  7. PSO-MISMO modeling strategy for multistep-ahead time series prediction.

    Science.gov (United States)

    Bao, Yukun; Xiong, Tao; Hu, Zhongyi

    2014-05-01

    Multistep-ahead time series prediction is one of the most challenging research topics in the field of time series modeling and prediction, and is continually under research. Recently, the multiple-input several multiple-outputs (MISMO) modeling strategy has been proposed as a promising alternative for multistep-ahead time series prediction, exhibiting advantages compared with the two currently dominating strategies, the iterated and the direct strategies. Built on the established MISMO strategy, this paper proposes a particle swarm optimization (PSO)-based MISMO modeling strategy, which is capable of determining the number of sub-models in a self-adaptive mode, with varying prediction horizons. Rather than deriving crisp divides with equal-size s prediction horizons from the established MISMO, the proposed PSO-MISMO strategy, implemented with neural networks, employs a heuristic to create flexible divides with varying sizes of prediction horizons and to generate corresponding sub-models, providing considerable flexibility in model construction, which has been validated with simulated and real datasets.

  8. A numerical strategy for modelling rotating stall in core compressors

    Science.gov (United States)

    Vahdati, M.

    2007-03-01

    The paper will focus on one specific core-compressor instability, rotating stall, because of the pressing industrial need to improve current design methods. The determination of the blade response during rotating stall is a difficult problem for which there is no reliable procedure. During rotating stall, the blades encounter the stall cells and the excitation depends on the number, size, exact shape and rotational speed of these cells. The long-term aim is to minimize the forced response due to rotating stall excitation by avoiding potential matches between the vibration modes and the rotating stall pattern characteristics. Accurate numerical simulations of core-compressor rotating stall phenomena require the modelling of a large number of bladerows using grids containing several tens of millions of points. The time-accurate unsteady-flow computations may need to be run for several engine revolutions for rotating stall to get initiated and many more before it is fully developed. The difficulty in rotating stall initiation arises from a lack of representation of the triggering disturbances which are inherently present in aeroengines. Since the numerical model represents a symmetric assembly, the only random mechanism for rotating stall initiation is provided by numerical round-off errors. In this work, rotating stall is initiated by introducing a small amount of geometric mistuning to the rotor blades. Another major obstacle in modelling flows near stall is the specification of appropriate upstream and downstream boundary conditions. Obtaining reliable boundary conditions for such flows can be very difficult. In the present study, the low-pressure compression (LPC) domain is placed upstream of the core compressor. With such an approach, only far field atmospheric boundary conditions are specified which are obtained from aircraft speed and altitude. A chocked variable-area nozzle, placed after the last compressor bladerow in the model, is used to impose boundary

  9. Organizational models as configurations of structure, culture, leadership, control, and change strategy

    Directory of Open Access Journals (Sweden)

    Janićijević Nebojša

    2017-01-01

    Full Text Available Starting from the axioms of consistency, stability, contingency, and configuration, research on organizational structure, culture, control, leadership, and change management strategy has shown that their typical configurations, or models, can be differentiated according to the same two criteria: distribution of power and dominant organizational dimension. On the one hand there are models of structure, culture, control, leadership, and change management strategy that are based on an unequal, or authoritarian, distribution of power within organizations, while on the other hand there are models that are based on democratic, or equal, distribution of power. Also, on the one hand there are models of structure, culture, control, leadership, and change strategy that are based on work structure and tasks, while on the other hand there are models of these organizational components that are based on social structure, people, and their relationships. Harmonization of typical configurations of organizational structure, culture, control, leadership, and change strategy occurs due to the harmonization of the differentiation criteria. Based on this harmonization, four organizational models have been identified as typical configurations of structure, culture, control, leadership, and change strategy: the autocratic, bureaucratic, innovative, and task models. Each of these models is effective in a different environmental contingency.

  10. Model-based control strategies for systems with constraints of the program type

    Science.gov (United States)

    Jarzębowska, Elżbieta

    2006-08-01

    The paper presents a model-based tracking control strategy for constrained mechanical systems. Constraints we consider can be material and non-material ones referred to as program constraints. The program constraint equations represent tasks put upon system motions and they can be differential equations of orders higher than one or two, and be non-integrable. The tracking control strategy relies upon two dynamic models: a reference model, which is a dynamic model of a system with arbitrary order differential constraints and a dynamic control model. The reference model serves as a motion planner, which generates inputs to the dynamic control model. It is based upon a generalized program motion equations (GPME) method. The method enables to combine material and program constraints and merge them both into the motion equations. Lagrange's equations with multipliers are the peculiar case of the GPME, since they can be applied to systems with constraints of first orders. Our tracking strategy referred to as a model reference program motion tracking control strategy enables tracking of any program motion predefined by the program constraints. It extends the "trajectory tracking" to the "program motion tracking". We also demonstrate that our tracking strategy can be extended to a hybrid program motion/force tracking.

  11. Research Strategy for Modeling the Complexities of Turbine Heat Transfer

    Science.gov (United States)

    Simoneau, Robert J.

    1996-01-01

    The subject of this paper is a NASA research program, known as the Coolant Flow Management Program, which focuses on the interaction between the internal coolant channel and the external film cooling of a turbine blade and/or vane in an aircraft gas turbine engine. The turbine gas path is really a very complex flow field. The combination of strong pressure gradients, abrupt geometry changes and intersecting surfaces, viscous forces, rotation, and unsteady blade/vane interactions all combine to offer a formidable challenge. To this, in the high pressure turbine, we add the necessity of film cooling. The ultimate goal of the turbine designer is to maintain or increase the high level of turbine performance and at the same time reduce the amount of coolant flow needed to achieve this end. Simply stated, coolant flow is a penalty on the cycle and reduces engine thermal efficiency. Accordingly, understanding the flow field and heat transfer associated with the coolant flow is a priority goal. It is important to understand both the film cooling and the internal coolant flow, particularly their interaction. Thus, the motivation for the Coolant Flow Management Program. The paper will begin with a brief discussion of the management and research strategy, will then proceed to discuss the current attack from the internal coolant side, and will conclude by looking at the film cooling effort - at all times keeping sight of the primary goal the interaction between the two. One of the themes of this paper is that complex heat transfer problems of this nature cannot be attacked by single researchers or even groups of researchers, each working alone. It truly needs the combined efforts of a well-coordinated team to make an impact. It is important to note that this is a government/industry/university team effort.

  12. Nonlinear Economic Model Predictive Control Strategy for Active Smart Buildings

    DEFF Research Database (Denmark)

    Santos, Rui Mirra; Zong, Yi; Sousa, Joao M. C.

    2016-01-01

    Nowadays, the development of advanced and innovative intelligent control techniques for energy management in buildings is a key issue within the smart grid topic. A nonlinear economic model predictive control (EMPC) scheme, based on the branch-and-bound tree search used as optimization algorithm ...... controller is shown very reliable keeping the comfort levels in the two considered seasons and shifting the load away from peak hours in order to achieve the desired flexible electricity consumption.......Nowadays, the development of advanced and innovative intelligent control techniques for energy management in buildings is a key issue within the smart grid topic. A nonlinear economic model predictive control (EMPC) scheme, based on the branch-and-bound tree search used as optimization algorithm...

  13. Social models of disability and other life strategies

    OpenAIRE

    Shakespeare, Tom

    2009-01-01

    The UK social model of disability (SSM) originated within a political context, which is both a strength and a weakness. Good social research has been conducted prior to, and outside, the confines of the SSM. The SSM is above all a brilliant tool for mobilising change. But it can be applied over‐zealously. Since the 1990s, various critiques of the SSM have been developed, exposing contradictions and inadequacies. Equally, some of the parallels between disability and other social movements may ...

  14. Model Strategi Prospektif Kinerja Manajemen di Perusahaan Tour & Travel

    Directory of Open Access Journals (Sweden)

    Rudy Aryanto

    2010-11-01

    Full Text Available This study aimed to build a prospective management model of sustainable tour packages in PT. Golden Rama Express. Given the complexity and the many interrelated factors in the performance management packagetours, it is necessary to approach a holistic system. First, the method used in developing the performance management model is a sustainable package tour and, second, using prospective analysis. Determination of the attributes that reflect the sustainability performance of the tour package is based on field studies. Based on the four dimensions of sustainability, namely the dimensions before the trip, during trip, etc., and the tour leader aredetermined as much as 23 attributes. Attributes in four dimensions for each package tour Junglelicious Africa, Asia Splendid, Adventurous Australia and New Zealand, Europe Romantical and Marvelous the U.S. and Canada. After obtained the level of sustainability index values of each dimension that can be categorized into the not sustainable until very sustainable values of the index, combination of these factors forms the basis of development models.. Based on the scenario that was built and in order to achieve the ideal scenario is the recommended scenario is the optimistic scenario.

  15. Geological Site Descriptive Model. A strategy for the model development during site investigations

    International Nuclear Information System (INIS)

    Munier, Raymond; Stenberg, Leif; Stanfors, Roy; Milnes, Allan Geoffrey; Hermanson, Jan; Triumf, Carl-Axel

    2003-04-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is at present conducting site investigations as a preliminary to building an underground nuclear waste disposal facility in Sweden. This report presents a methodology for constructing, visualising and presenting 3-dimensional geological models, based on data from the site investigations. The methodology integrates with the overall work-flow of the site investigations, from the collection of raw data to the complete site description, as proposed in several earlier technical reports. Further, it is specifically designed for interaction with SICADA - SKB's Site Characterisation Database - and RVS - SKB's Rock Visualisation System. This report is one in a series of strategy documents intended to demonstrate how modelling is to be performed within each discipline. However, it also has a wider purpose, since the geological site descriptive model provides the basic geometrical framework for all the other disciplines. Hence, the wider aim is to present a practical and clear methodology for the analysis and interpretation of input data for use in the construction of the geology-based 3D geometrical model. In addition to the various aspects of modelling described above, the methodology presented here should therefore also provide: guidelines and directives on how systematic interpretation and integration of geo-scientific data from the different investigation methods should be carried out; guidelines on how different geometries should be created in the geological models; guidelines on how the assignment of parameters to the different geological units in RVS should be accomplished; guidelines on the handling of uncertainty at different points in the interpretation process. In addition, it should clarify the relation between the geological model and other models used in the processes of site characterisation, repository layout and safety analysis. In particular, integration and transparency should be promoted. The

  16. Geological Site Descriptive Model. A strategy for the model development during site investigations

    Energy Technology Data Exchange (ETDEWEB)

    Munier, Raymond; Stenberg, Leif [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Stanfors, Roy [Roy Stanfors Consulting, Lund (Sweden); Milnes, Allan Geoffrey [GEA Consulting, Uppsala (Sweden); Hermanson, Jan [Golder Associates, Stockholm (Sweden); Triumf, Carl-Axel [Geovista, Luleaa (Sweden)

    2003-04-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is at present conducting site investigations as a preliminary to building an underground nuclear waste disposal facility in Sweden. This report presents a methodology for constructing, visualising and presenting 3-dimensional geological models, based on data from the site investigations. The methodology integrates with the overall work-flow of the site investigations, from the collection of raw data to the complete site description, as proposed in several earlier technical reports. Further, it is specifically designed for interaction with SICADA - SKB's Site Characterisation Database - and RVS - SKB's Rock Visualisation System. This report is one in a series of strategy documents intended to demonstrate how modelling is to be performed within each discipline. However, it also has a wider purpose, since the geological site descriptive model provides the basic geometrical framework for all the other disciplines. Hence, the wider aim is to present a practical and clear methodology for the analysis and interpretation of input data for use in the construction of the geology-based 3D geometrical model. In addition to the various aspects of modelling described above, the methodology presented here should therefore also provide: guidelines and directives on how systematic interpretation and integration of geo-scientific data from the different investigation methods should be carried out; guidelines on how different geometries should be created in the geological models; guidelines on how the assignment of parameters to the different geological units in RVS should be accomplished; guidelines on the handling of uncertainty at different points in the interpretation process. In addition, it should clarify the relation between the geological model and other models used in the processes of site characterisation, repository layout and safety analysis. In particular, integration and transparency should be

  17. Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Seethambal S.; van Bloemen Waanders, Bart Gustaaf; Cooper, Scott Patrick; Jakaboski, Blake Elaine; Normann, Randy Allen; Jennings, Jim (University of Texas at Austin, Austin, TX); Gilbert, Bob (University of Texas at Austin, Austin, TX); Lake, Larry W. (University of Texas at Austin, Austin, TX); Weiss, Chester Joseph; Lorenz, John Clay; Elbring, Gregory Jay; Wheeler, Mary Fanett (University of Texas at Austin, Austin, TX); Thomas, Sunil G. (University of Texas at Austin, Austin, TX); Rightley, Michael J.; Rodriguez, Adolfo (University of Texas at Austin, Austin, TX); Klie, Hector (University of Texas at Austin, Austin, TX); Banchs, Rafael (University of Texas at Austin, Austin, TX); Nunez, Emilio J. (University of Texas at Austin, Austin, TX); Jablonowski, Chris (University of Texas at Austin, Austin, TX)

    2006-11-01

    The project objective was to detail better ways to assess and exploit intelligent oil and gas field information through improved modeling, sensor technology, and process control to increase ultimate recovery of domestic hydrocarbons. To meet this objective we investigated the use of permanent downhole sensors systems (Smart Wells) whose data is fed real-time into computational reservoir models that are integrated with optimized production control systems. The project utilized a three-pronged approach (1) a value of information analysis to address the economic advantages, (2) reservoir simulation modeling and control optimization to prove the capability, and (3) evaluation of new generation sensor packaging to survive the borehole environment for long periods of time. The Value of Information (VOI) decision tree method was developed and used to assess the economic advantage of using the proposed technology; the VOI demonstrated the increased subsurface resolution through additional sensor data. Our findings show that the VOI studies are a practical means of ascertaining the value associated with a technology, in this case application of sensors to production. The procedure acknowledges the uncertainty in predictions but nevertheless assigns monetary value to the predictions. The best aspect of the procedure is that it builds consensus within interdisciplinary teams The reservoir simulation and modeling aspect of the project was developed to show the capability of exploiting sensor information both for reservoir characterization and to optimize control of the production system. Our findings indicate history matching is improved as more information is added to the objective function, clearly indicating that sensor information can help in reducing the uncertainty associated with reservoir characterization. Additional findings and approaches used are described in detail within the report. The next generation sensors aspect of the project evaluated sensors and packaging

  18. Benchmark Simulation Model No 2 – finalisation of plant layout and default control strategy

    DEFF Research Database (Denmark)

    Nopens, I.; Benedetti, L.; Jeppsson, U.

    2010-01-01

    The COST/IWA Benchmark Simulation Model No 1 (BSM1) has been available for almost a decade. Its primary purpose has been to create a platform for control strategy benchmarking of activated sludge processes. The fact that the research work related to the benchmark simulation models has resulted...... in more than 300 publications worldwide demonstrates the interest in and need of such tools within the research community. Recent efforts within the IWA Task Group on “Benchmarking of control strategies for WWTPs” have focused on an extension of the benchmark simulation model. This extension aims...... be evaluated in a realistic fashion in the one week BSM1 evaluation period. In this paper, the finalised plant layout is summarised and, as was done for BSM1, a default control strategy is proposed. A demonstration of how BSM2 can be used to evaluate control strategies is also given....

  19. An Optimization Model For Strategy Decision Support to Select Kind of CPO’s Ship

    Science.gov (United States)

    Suaibah Nst, Siti; Nababan, Esther; Mawengkang, Herman

    2018-01-01

    The selection of marine transport for the distribution of crude palm oil (CPO) is one of strategy that can be considered in reducing cost of transport. The cost of CPO’s transport from one area to CPO’s factory located at the port of destination may affect the level of CPO’s prices and the number of demands. In order to maintain the availability of CPO a strategy is required to minimize the cost of transporting. In this study, the strategy used to select kind of charter ships as barge or chemical tanker. This study aims to determine an optimization model for strategy decision support in selecting kind of CPO’s ship by minimizing costs of transport. The select of ship was done randomly, so that two-stage stochastic programming model was used to select the kind of ship. Model can help decision makers to select either barge or chemical tanker to distribute CPO.

  20. The Development and Empirical Validation of an E-based Supply Chain Strategy Optimization Model

    DEFF Research Database (Denmark)

    Kotzab, Herbert; Skjoldager, Niels; Vinum, Thorkil

    2003-01-01

    Examines the formulation of supply chain strategies in complex environments. Argues that current state‐of‐the‐art e‐business and supply chain management, combined into the concept of e‐SCM, as well as the use of transaction cost theory, network theory and resource‐based theory, altogether can...... be used to form a model for analyzing supply chains with the purpose of reducing the uncertainty of formulating supply chain strategies. Presents e‐supply chain strategy optimization model (e‐SOM) as a way to analyze supply chains in a structured manner as regards strategic preferences for supply chain...... design, relations and resources in the chains with the ultimate purpose of enabling the formulation of optimal, executable strategies for specific supply chains. Uses research results for a specific supply chain to validate the usefulness of the model....

  1. Pengembangan Model Navigasi Nilai Sosial Untuk Mendukung Kerangka Kerja Pengembangan Strategi Organisasi Sosial Di Dalam Choeling Indonesia

    OpenAIRE

    Ledy, Ledy; Simatupang, Togar M

    2013-01-01

    Every social organization has a unique different business model in providing services to the society. The social business model is often derived from a selected strategy. However, the strategy merely directs the social business model to construct its elements by neglecting value related aspects. There is no formal social business model concept that assists any strategy framework used as the basic structure for identifying a business model, especially the value concerned business model. The ai...

  2. A Combined Cooperative Braking Model with a Predictive Control Strategy in an Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Hongqiang Guo

    2013-12-01

    Full Text Available Cooperative braking with regenerative braking and mechanical braking plays an important role in electric vehicles for energy-saving control. Based on the parallel and the series cooperative braking models, a combined model with a predictive control strategy to get a better cooperative braking performance is presented. The balance problem between the maximum regenerative energy recovery efficiency and the optimum braking stability is solved through an off-line process optimization stream with the collaborative optimization algorithm (CO. To carry out the process optimization stream, the optimal Latin hypercube design (Opt LHD is presented to discrete the continuous design space. To solve the poor real-time problem of the optimization, a high-precision predictive model based on the off-line optimization data of the combined model is built, and a predictive control strategy is proposed and verified through simulation. The simulation results demonstrate that the predictive control strategy and the combined model are reasonable and effective.

  3. Business Model Warfare: The Strategy of Business Breakthroughs

    Directory of Open Access Journals (Sweden)

    Langdon Morris

    2013-12-01

    Full Text Available There’s a story behind every business success and every business failure, sometimes the story of a great idea; sometimes one that failed. Sometimes it’s a story of insightful management, or management that failed. But almost always it’s a story about change. Change in the market; change in the economy; change in a particular product or service that transformed a failure into a success, or vice versa. Hidden behind many of these changes, or sometimes as a result of them, there is change in what customers experience, and as a result, a change in their perceptions and attitudes, and then in their buying habits. Companies soar, or collapse, as a consequence. While we study the stories to learn about the specific changes, events, insights, and breakdowns in each case, we also look for broader and deeper explanations that show how change applies across industries and the whole of the economy. The broader patterns are often Business Model Innovations, the subject of this white paper. Here we propose a specific model explaining how large companies create and sustain market leadership in today’s market, or the traps that they fall into that prevent them from doing so.

  4. Industrial waste recycling strategies optimization problem: mixed integer programming model and heuristics

    Science.gov (United States)

    Tang, Jiafu; Liu, Yang; Fung, Richard; Luo, Xinggang

    2008-12-01

    Manufacturers have a legal accountability to deal with industrial waste generated from their production processes in order to avoid pollution. Along with advances in waste recovery techniques, manufacturers may adopt various recycling strategies in dealing with industrial waste. With reuse strategies and technologies, byproducts or wastes will be returned to production processes in the iron and steel industry, and some waste can be recycled back to base material for reuse in other industries. This article focuses on a recovery strategies optimization problem for a typical class of industrial waste recycling process in order to maximize profit. There are multiple strategies for waste recycling available to generate multiple byproducts; these byproducts are then further transformed into several types of chemical products via different production patterns. A mixed integer programming model is developed to determine which recycling strategy and which production pattern should be selected with what quantity of chemical products corresponding to this strategy and pattern in order to yield maximum marginal profits. The sales profits of chemical products and the set-up costs of these strategies, patterns and operation costs of production are considered. A simulated annealing (SA) based heuristic algorithm is developed to solve the problem. Finally, an experiment is designed to verify the effectiveness and feasibility of the proposed method. By comparing a single strategy to multiple strategies in an example, it is shown that the total sales profit of chemical products can be increased by around 25% through the simultaneous use of multiple strategies. This illustrates the superiority of combinatorial multiple strategies. Furthermore, the effects of the model parameters on profit are discussed to help manufacturers organize their waste recycling network.

  5. Mud, models, and managers: Reaching consensus on a watershed strategy for sediment load reduction

    Science.gov (United States)

    Wilcock, P. R.; Cho, S. J.; Gran, K.; Belmont, P.; Hobbs, B. F.; Heitkamp, B.; Marr, J. D.

    2017-12-01

    Agricultural nonpoint source sediment pollution is a leading cause of impairment of U.S. waters. Sediment sources are often on private land, such that solutions require not only considerable investment, but broad acceptance among landowners. We present the story of a participatory modeling exercise whose goal was to develop a consensus strategy for reducing sediment loading from the Greater Blue Earth River Basin, a large (9,200 km2) watershed in southern Minnesota dominated by row crop agriculture. The Collaborative for Sediment Source Reduction was a stakeholder group of farmers, industry representatives, conservation groups, and regulatory agencies. We used a participatory modeling approach to promote understanding of the problem, to define the scope of solutions acceptable to farmers, to develop confidence in a watershed model, and to reach consensus on a watershed strategy. We found that no existing watershed model could provide a reliable estimate of sediment response to management actions and developed a purpose-built model that could provide reliable, transparent, and fast answers. Because increased stream flow was identified as an important driver of sediment loading, the model and solutions included both hydrologic and sediment transport components. The model was based on an annual sediment budget with management actions serving to proportionally reduce both sediment sources and sediment delivery. Importantly, the model was developed in collaboration with stakeholders, such that a shared understanding emerged regarding of the modeling challenges and the reliability of information used to strongly constrain model output. The simplicity of the modeling approach supported stakeholder engagement and understanding, thereby lowering the social barrier between expert modeler and concerned stakeholder. The consensus strategy focused on water storage higher in the watershed in order to reduce river discharge and the large supply of sediment from near

  6. A proposed strategy for the validation of ground-water flow and solute transport models

    International Nuclear Information System (INIS)

    Davis, P.A.; Goodrich, M.T.

    1991-01-01

    Ground-water flow and transport models can be thought of as a combination of conceptual and mathematical models and the data that characterize a given system. The judgment of the validity or invalidity of a model depends both on the adequacy of the data and the model structure (i.e., the conceptual and mathematical model). This report proposes a validation strategy for testing both components independently. The strategy is based on the philosophy that a model cannot be proven valid, only invalid or not invalid. In addition, the authors believe that a model should not be judged in absence of its intended purpose. Hence, a flow and transport model may be invalid for one purpose but not invalid for another. 9 refs

  7. Design Protocols and Analytical Strategies that Incorporate Structural Reliability Models

    Science.gov (United States)

    Duffy, Stephen F.

    1997-01-01

    Ceramic matrix composites (CMC) and intermetallic materials (e.g., single crystal nickel aluminide) are high performance materials that exhibit attractive mechanical, thermal and chemical properties. These materials are critically important in advancing certain performance aspects of gas turbine engines. From an aerospace engineer's perspective the new generation of ceramic composites and intermetallics offers a significant potential for raising the thrust/weight ratio and reducing NO(x) emissions of gas turbine engines. These aspects have increased interest in utilizing these materials in the hot sections of turbine engines. However, as these materials evolve and their performance characteristics improve a persistent need exists for state-of-the-art analytical methods that predict the response of components fabricated from CMC and intermetallic material systems. This need provided the motivation for the technology developed under this research effort. Continuous ceramic fiber composites exhibit an increase in work of fracture, which allows for "graceful" rather than catastrophic failure. When loaded in the fiber direction, these composites retain substantial strength capacity beyond the initiation of transverse matrix cracking despite the fact that neither of its constituents would exhibit such behavior if tested alone. As additional load is applied beyond first matrix cracking, the matrix tends to break in a series of cracks bridged by the ceramic fibers. Any additional load is born increasingly by the fibers until the ultimate strength of the composite is reached. Thus modeling efforts supported under this research effort have focused on predicting this sort of behavior. For single crystal intermetallics the issues that motivated the technology development involved questions relating to material behavior and component design. Thus the research effort supported by this grant had to determine the statistical nature and source of fracture in a high strength, Ni

  8. Model-Based Nutrient Feeding Strategies for the Increased Production of Polyhydroxybutyrate (PHB) by Alcaligenes latus.

    Science.gov (United States)

    Gahlawat, Geeta; Srivastava, Ashok K

    2017-10-01

    Polyhydroxyalkanoates (PHAs) are biodegradable polymers which are considered as an effective alternative for conventional plastics due to their mechanical properties similar to the latter. However, the widespread use of these polymers is still hampered due to their higher cost of production as compared to plastics. The production cost could be overcome by obtaining high yields and productivity. The goal of the present research was to enhance the yield of polyhydroxybutyrate (PHB) with the help of two simple fed-batch cultivation strategies. In the present study, average batch kinetic and substrate limitation/inhibition study data of Alcaligenes latus was used for the development of PHB model which was then adopted for designing various off-line nutrient feeding strategies to enhance PHB accumulation. The predictive ability of the model was validated by experimental implementation of two fed-batch strategies. One such dynamic strategy of fed-batch cultivation under pseudo-steady state with respect to nitrogen and simultaneous carbon feeding strategy resulted in significantly high biomass and PHB concentration of 39.17 g/L and 29.64 g/L, respectively. This feeding strategy demonstrated a high PHB productivity and PHB content of 0.6 g/L h and 75%, respectively, which were remarkably high in comparison to batch cultivation. The mathematical model can also be employed for designing various other nutrient feeding strategies.

  9. Methodological notes on model comparisons and strategy classification: A falsificationist proposition

    OpenAIRE

    Morten Moshagen; Benjamin E. Hilbig

    2011-01-01

    Taking a falsificationist perspective, the present paper identifies two major shortcomings of existing approaches to comparative model evaluations in general and strategy classifications in particular. These are (1) failure to consider systematic error and (2) neglect of global model fit. Using adherence measures to evaluate competing models implicitly makes the unrealistic assumption that the error associated with the model predictions is entirely random. By means of simple schematic example...

  10. Predictive models to determine imagery strategies employed by children to judge hand laterality.

    Science.gov (United States)

    Spruijt, Steffie; Jongsma, Marijtje L A; van der Kamp, John; Steenbergen, Bert

    2015-01-01

    A commonly used paradigm to study motor imagery is the hand laterality judgment task. The present study aimed to determine which strategies young children employ to successfully perform this task. Children of 5 to 8 years old (N = 92) judged laterality of back and palm view hand pictures in different rotation angles. Response accuracy and response duration were registered. Response durations of the trials with a correct judgment were fitted to a-priori defined predictive sinusoid models, representing different strategies to successfully perform the hand laterality judgment task. The first model predicted systematic changes in response duration as a function of rotation angle of the displayed hand. The second model predicted that response durations are affected by biomechanical constraints of hand rotation. If observed data could be best described by the first model, this would argue for a mental imagery strategy that does not involve motor processes to solve the task. The second model reflects a motor imagery strategy to solve the task. In line with previous research, we showed an age-related increase in response accuracy and decrease in response duration in children. Observed data for both back and palm view showed that motor imagery strategies were used to perform hand laterality judgments, but that not all the children use these strategies (appropriately) at all times. A direct comparison of response duration patterns across age sheds new light on age-related differences in the strategies employed to solve the task. Importantly, the employment of the motor imagery strategy for successful task performance did not change with age.

  11. Value-added strategy models to provide quality services in senior health business.

    Science.gov (United States)

    Yang, Ya-Ting; Lin, Neng-Pai; Su, Shyi; Chen, Ya-Mei; Chang, Yao-Mao; Handa, Yujiro; Khan, Hafsah Arshed Ali; Elsa Hsu, Yi-Hsin

    2017-06-20

    The rapid population aging is now a global issue. The increase in the elderly population will impact the health care industry and health enterprises; various senior needs will promote the growth of the senior health industry. Most senior health studies are focused on the demand side and scarcely on supply. Our study selected quality enterprises focused on aging health and analyzed different strategies to provide excellent quality services to senior health enterprises. We selected 33 quality senior health enterprises in Taiwan and investigated their excellent quality services strategies by face-to-face semi-structured in-depth interviews with CEO and managers of each enterprise in 2013. A total of 33 senior health enterprises in Taiwan. Overall, 65 CEOs and managers of 33 enterprises were interviewed individually. None. Core values and vision, organization structure, quality services provided, strategies for quality services. This study's results indicated four type of value-added strategy models adopted by senior enterprises to offer quality services: (i) residential care and co-residence model, (ii) home care and living in place model, (iii) community e-business experience model and (iv) virtual and physical portable device model. The common part in these four strategy models is that the services provided are elderly centered. These models offer virtual and physical integrations, and also offer total solutions for the elderly and their caregivers. Through investigation of successful strategy models for providing quality services to seniors, we identified opportunities to develop innovative service models and successful characteristics, also policy implications were summarized. The observations from this study will serve as a primary evidenced base for enterprises developing their senior market and, also for promoting the value co-creation possibility through dialogue between customers and those that deliver service. © The Author 2017. Published by Oxford

  12. Sex determination strategies in 2012: towards a common regulatory model?

    Science.gov (United States)

    2012-01-01

    Sex determination is a complicated process involving large-scale modifications in gene expression affecting virtually every tissue in the body. Although the evolutionary origin of sex remains controversial, there is little doubt that it has developed as a process of optimizing metabolic control, as well as developmental and reproductive functions within a given setting of limited resources and environmental pressure. Evidence from various model organisms supports the view that sex determination may occur as a result of direct environmental induction or genetic regulation. The first process has been well documented in reptiles and fish, while the second is the classic case for avian species and mammals. Both of the latter have developed a variety of sex-specific/sex-related genes, which ultimately form a complete chromosome pair (sex chromosomes/gonosomes). Interestingly, combinations of environmental and genetic mechanisms have been described among different classes of animals, thus rendering the possibility of a unidirectional continuous evolutionary process from the one type of mechanism to the other unlikely. On the other hand, common elements appear throughout the animal kingdom, with regard to a) conserved key genes and b) a central role of sex steroid control as a prerequisite for ultimately normal sex differentiation. Studies in invertebrates also indicate a role of epigenetic chromatin modification, particularly with regard to alternative splicing options. This review summarizes current evidence from research in this hot field and signifies the need for further study of both normal hormonal regulators of sexual phenotype and patterns of environmental disruption. PMID:22357269

  13. Video Self-Modeling: A Promising Strategy for Noncompliant Children.

    Science.gov (United States)

    Axelrod, Michael I; Bellini, Scott; Markoff, Kimberly

    2014-07-01

    The current study investigated the effects of a Video Self-Modeling (VSM) intervention on the compliance and aggressive behavior of three children placed in a psychiatric hospital. Each participant viewed brief video clips of himself following simple adult instructions just prior to the school's morning session and the unit's afternoon free period. A multiple baseline design across settings was used to evaluate the effects of the VSM intervention on compliance with staff instructions and aggressive behavior on the hospital unit and in the hospital-based classroom. All three participants exhibited higher levels of compliance and fewer aggressive episodes during the intervention condition, and the effects were generally maintained when the intervention was withdrawn. Hospital staff reported at the conclusion of the study that the VSM intervention was easy to implement and beneficial for all participants. Taken altogether, the results suggest VSM is a promising, socially acceptable, and proactive intervention approach for improving the behavior of noncompliant children. © The Author(s) 2014.

  14. A Development English Language Learning Management Strategies Model to Enhance Communicative Competence for High School Students

    Directory of Open Access Journals (Sweden)

    Thitiya Ruennakarn

    2017-09-01

    Full Text Available The objectives for this research are to 1 build a development English language learning management strategies model to enhance communicative competence for high school students 2 study the results of using the model. A target group is seven English teachers in Pibulwittayalai School and the sample for studying the results of model to students are ten English club students in Pibulwittayalai School.The research tools are focus group discussion forms, communication plans, English skills evaluation forms, communicative competence test, communicative competence evaluation forms and 21st century skills evaluation forms. This model is examined by connoisseurship.The statistics for analyzing data are frequency, percentage, mean, standard deviation and Wilcoxon test. The results of the research were as follows: 1. The development English language learning management strategies model to enhance communicative competence for high school students had4components ; 1 SWOT–Analysis, 2 strategy development, 3 strategy assessment and 4 strategy adjustment.This model had 6 strategies such as 1 genius academic strategy 2 English through AEC 3 English through World Class 4 enhancing for genius academic in communication with foreigners 5 enhancing English through world class standard and 6 enhancing for potential in English skills learning through world class standard. These were merged as only one strategy as “ Development of students’ potential for communication”. 2. The results of using the model comprised of 2.1 The results to teachers were teachers could analyze SWOT- analysis for determining strength, weakness,opportunity and threat about English language learning management, received guideline and could appropriately and efficiently construct strategies of English language learning management to enhance communicative competence. 2.2 The results to students: The students had 4 English skills, such as listening,speaking, reading and writing. It was

  15. Transformation Strategies between Block-Oriented and Graph-Oriented Process Modelling Languages

    DEFF Research Database (Denmark)

    Mendling, Jan; Lassen, Kristian Bisgaard; Zdun, Uwe

    2006-01-01

    Much recent research work discusses the transformation between different process modelling languages. This work, however, is mainly focussed on specific process modelling languages, and thus the general reusability of the applied transformation concepts is rather limited. In this paper, we aim...... to abstract from concrete transformation strategies by distinguishing two major paradigms for representing control flow in process modelling languages: block-oriented languages (such as BPEL and BPML) and graph-oriented languages (such as EPCs and YAWL). The contribution of this paper are generic strategies...... for transforming from block-oriented process languages to graph-oriented languages, and vice versa....

  16. The design, results and future development of the National Energy Strategy Environmental Analysis Model (NESEAM)

    International Nuclear Information System (INIS)

    Fisher, R.E.; Boyd, G.A.; Breed, W.S.

    1991-01-01

    The National Energy Strategy Environmental Model (NESEAM) has been developed to project emissions for the National Energy Strategy (NES). Two scenarios were evaluated for the NES, a Current Policy Base Case and a NES Action Case. The results from the NES Actions Case project much lower emissions than the Current Policy Base Case. Future enhancements to NESEAM will focus on fuel cycle analysis, including future technologies and additional pollutants to model. NESEAM's flexibility will allow it to model other future legislative issues. 7 refs., 4 figs., 2 tabs

  17. Nephrology around Europe: organization models and management strategies: Spain.

    Science.gov (United States)

    de Francisco, Angel L M; Piñera, Celestino

    2011-01-01

    The main aim of this report is to present a picture of the current organization of nephrology in Spain. The Spanish health system offers almost universal coverage, a wide variety of services and a high-quality network of hospitals and primary care centers. Spain has a specialized health care training system that is highly developed, highly regulated, with the capacity to provide high-quality training in 54 different specialties. Nephrology is basically a hospital-based specialty. There are no private dialysis patients in Spain. Hemodialysis centers are 40% public, 15% private and 45% run by companies. The National Health System covers 95% of the population, and there is no cost to patients for treatment of renal disease (dialysis and transplant). We observed a clear decrease of nephrology in residents' election rankings, with position 29 out of 47 specialties in 2007. Some of the reasons for this are the complexity of the subject, no clear information at the university, reduction of professional posts and a very good public service with minimal private practice. In Spain, a model of organization for transplantation was adopted based on a decentralized transplant coordinating network. For cadaveric donors, it compares favorably with rates in other Western countries. Living donor transplantation is very low in Spain--just 10% of total renal transplantation activity. New programs due to financial constraints need to include reduced dialysis costs, greater cost-effectiveness of prescriptions, better handling of ethical issues related to the need for using a clinical score of chronic kidney disease patients to make decisions about conservative or renal replacement therapy and an action plan for improvement of organ donation and transplantation. Recovery of skills (acute kidney injury, biopsies, vascular access, etc.), research and advances in autonomous activities (imaging, surgical and medical vascular training, etc.) are some of the future educational paths needed in

  18. State impulsive control strategies for a two-languages competitive model with bilingualism and interlinguistic similarity

    Science.gov (United States)

    Nie, Lin-Fei; Teng, Zhi-Dong; Nieto, Juan J.; Jung, Il Hyo

    2015-07-01

    For reasons of preserving endangered languages, we propose, in this paper, a novel two-languages competitive model with bilingualism and interlinguistic similarity, where state-dependent impulsive control strategies are introduced. The novel control model includes two control threshold values, which are different from the previous state-dependent impulsive differential equations. By using qualitative analysis method, we obtain that the control model exhibits two stable positive order-1 periodic solutions under some general conditions. Moreover, numerical simulations clearly illustrate the main theoretical results and feasibility of state-dependent impulsive control strategies. Meanwhile numerical simulations also show that state-dependent impulsive control strategy can be applied to other general two-languages competitive model and obtain the desired result. The results indicate that the fractions of two competitive languages can be kept within a reasonable level under almost any circumstances. Theoretical basis for finding a new control measure to protect the endangered language is offered.

  19. Hydrogeochemical site descriptive model - a strategy for the model development during site investigations

    International Nuclear Information System (INIS)

    Smellie, John; Laaksoharju, Marcus; Tullborg, Eva-Lena

    2002-12-01

    In 2002, SKB commenced site characterisation investigations using deep boreholes at different sites. As an integral part of the planning work SKB has prepared a strategy to develop a Hydrogeochemical Site Descriptive Model; similar strategies have been developed for the other major geoscience disciplines. The main objectives of the Hydrogeochemical Site Descriptive Model are to describe the chemistry and distribution of the groundwater in the bedrock and overburden and the hydrogeochemical processes involved in its origin and evolution. This description is based primarily on measurements of the groundwater composition but incorporates the use of available geological and hydrogeological site descriptive models. The SKB hydrogeochemistry programme is planned to fulfil two basic requirements: 1) to provide representative and quality assured data for use as input parameter values in calculating long-term repository safety, and 2) to understand the present undisturbed hydrogeochemical conditions and how these conditions will change in the future. Parameter values for safety analysis include pH, Eh, S, SO 4 , HCO 3 , HPO 4 and TDS (mainly cations), together with colloids, fulvic and humic acids, other organics, bacteria and nitrogen. These values will be used to characterise the groundwater environment at, above and below repository depths. In the hydrogeochemical site investigation programme the number and location of the sampling points will be constrained by: a) geology (e.g. topography, overburden types, bedrock structures etc), b) hydrogeology (e.g. groundwater recharge/discharge areas, residence times), c) reliability (e.g. undisturbed vs disturbed groundwater chemical conditions), and d) resources (e.g. number and type of samples, and also available personnel, may be restricted by budgetary and schedule concerns). Naturally a balance is required between these constraints and the scientific aims of the programme. The constraints should never detrimentally affect

  20. DEFINING RECOVERY GOALS AND STRATEGIES FOR ENDANGERED SPECIES USING SPATIALLY-EXPLICIT POPULATION MODELS

    Science.gov (United States)

    We used a spatially explicit population model of wolves (Canis lupus) to propose a framework for defining rangewide recovery priorities and finer-scale strategies for regional reintroductions. The model predicts that Yellowstone and central Idaho, where wolves have recently been ...

  1. Modelling the carbon cycle of grassland in the Netherlands under various management strategies and environmental conditions.

    NARCIS (Netherlands)

    Pol-van Dasselaar, van den A.; Lantinga, E.A.

    1995-01-01

    A simulation model of the grassland carbon cycle (CCGRASS) was developed to evaluate the long-term effects of different management strategies and various environmental conditions on carbon sequestration in a loam soil under permanent grassland in the Netherlands. The model predicted that the rate of

  2. Video Self-Modeling as an Intervention Strategy for Individuals with Autism Spectrum Disorders

    Science.gov (United States)

    Gelbar, Nicholas W.; Anderson, Candace; McCarthy, Scott; Buggey, Tom

    2012-01-01

    Video self-modeling demonstrates promise as an intervention strategy to improve outcomes in individuals with autism spectrum disorders. This article summarizes the empirical evidence supporting the use of video self-modeling with individuals with autism spectrum disorders to increase language and communication, increase social skills, modify…

  3. Time-Varying Combinations of Bayesian Dynamic Models and Equity Momentum Strategies

    NARCIS (Netherlands)

    N. Basturk (Nalan); S. Grassi (Stefano); L.F. Hoogerheide (Lennart); H.K. van Dijk (Herman)

    2016-01-01

    markdownabstractA novel dynamic asset-allocation approach is proposed where portfolios as well as portfolio strategies are updated at every decision period based on their past performance. For modeling, a general class of models is specified that combines a dynamic factor and a vector autoregressive

  4. Developing a fuzzy ANP model for performance appraisal based on firm strategy

    Directory of Open Access Journals (Sweden)

    Seid Mohammad Reza Mirahmadi

    2018-10-01

    Full Text Available The purpose of this study is to develop a fuzzy Analytic Network Process (ANP model that has the ability to evaluate employee performance in different strategies. A team of experts in the field of strategic human resource management and senior management of an organization engaged in steel production were involved in the study. The data collection tool was a questionnaire that was designed based on the criteria of organization's performance appraisal system. The results showed that in cost leadership strategy, compliance of work hierarchy, quantity of work and the ability to make important decisions constituted the highest coefficients, while in the focus strategy, participate in group work, power of supervision and administration and decision making ability had the highest importance. In differentiation strategy, innovation and creativity, quality and offering constructive suggestions received higher ratings than other criteria. Finally, the developed model was used to evaluate the performance of a sample employee

  5. Cost-effectiveness of seven IVF strategies: results of a Markov decision-analytic model.

    Science.gov (United States)

    Fiddelers, Audrey A A; Dirksen, Carmen D; Dumoulin, John C M; van Montfoort, Aafke P A; Land, Jolande A; Janssen, J Marij; Evers, Johannes L H; Severens, Johan L

    2009-07-01

    A selective switch to elective single embryo transfer (eSET) in IVF has been suggested to prevent complications of fertility treatment for both mother and infants. We compared seven IVF strategies concerning their cost-effectiveness using a Markov model. The model was based on a three IVF-attempts time horizon and a societal perspective using real world strategies and data, comparing seven IVF strategies, concerning costs, live births and incremental cost-effectiveness ratios (ICERs). In order to increase pregnancy probability, one cycle of eSET + one cycle of standard treatment policy [STP, i.e. eSET in patients IVF treatment, combining several transfer policies was not cost-effective. A choice has to be made between three cycles of eSET, STP or DET. It depends, however, on society's willingness to pay which strategy is to be preferred from a cost-effectiveness point of view.

  6. Analytical connection between thresholds and immunization strategies of SIS model in random networks

    Science.gov (United States)

    Zhou, Ming-Yang; Xiong, Wen-Man; Liao, Hao; Wang, Tong; Wei, Zong-Wen; Fu, Zhong-Qian

    2018-05-01

    Devising effective strategies for hindering the propagation of viruses and protecting the population against epidemics is critical for public security and health. Despite a number of studies based on the susceptible-infected-susceptible (SIS) model devoted to this topic, we still lack a general framework to compare different immunization strategies in completely random networks. Here, we address this problem by suggesting a novel method based on heterogeneous mean-field theory for the SIS model. Our method builds the relationship between the thresholds and different immunization strategies in completely random networks. Besides, we provide an analytical argument that the targeted large-degree strategy achieves the best performance in random networks with arbitrary degree distribution. Moreover, the experimental results demonstrate the effectiveness of the proposed method in both artificial and real-world networks.

  7. Role Models in Science - An Effective Dissemination Strategy

    Science.gov (United States)

    Chatzichristou, Eleni; Daglis, Ioannis A.; Anastasiadis, Anastasios; Balasis, George; Bourdarie, Sebastien; Horne, Richard B.; Khotyaintsev, Yuri; Mann, Ian R.; Santolik, Ondrej; Turner, Drew L.; Giannakis, Omiros; Ropokis, George

    2014-05-01

    successful career path to both act as role model and to show the challenges that young scientists are facing today. The work leading to this paper has received funding from the European Union's Seventh Framework Programme (FP7-SPACE-2011-1) under grant agreement no. 284520 for the MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Energization and Loss) collaborative research project. This paper reflects only the authors' views and the Union is not liable for any use that may be made of the information contained therein.

  8. A model of extracellular enzymes in free-living microbes: which strategy pays off?

    Science.gov (United States)

    Traving, Sachia J; Thygesen, Uffe H; Riemann, Lasse; Stedmon, Colin A

    2015-11-01

    An initial modeling approach was applied to analyze how a single, nonmotile, free-living, heterotrophic bacterial cell may optimize the deployment of its extracellular enzymes. Free-living cells live in a dilute and complex substrate field, and to gain enough substrate, their extracellular enzymes must be utilized efficiently. The model revealed that surface-attached and free enzymes generate unique enzyme and substrate fields, and each deployment strategy has distinctive advantages. For a solitary cell, surface-attached enzymes are suggested to be the most cost-efficient strategy. This strategy entails potential substrates being reduced to very low concentrations. Free enzymes, on the other hand, generate a radically different substrate field, which suggests significant benefits for the strategy if free cells engage in social foraging or experience high substrate concentrations. Swimming has a slight positive effect for the attached-enzyme strategy, while the effect is negative for the free-enzyme strategy. The results of this study suggest that specific dissolved organic compounds in the ocean likely persist below a threshold concentration impervious to biological utilization. This could help explain the persistence and apparent refractory state of oceanic dissolved organic matter (DOM). Microbial extracellular enzyme strategies, therefore, have important implications for larger-scale processes, such as shaping the role of DOM in ocean carbon sequestration. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. Efficiency of alternative MCMC strategies illustrated using the reaction norm model

    DEFF Research Database (Denmark)

    Shariati, Mohammad Mahdi; Sørensen, D.

    2008-01-01

    The Markov chain Monte Carlo (MCMC) strategy provides remarkable flexibility for fitting complex hierarchical models. However, when parameters are highly correlated in their posterior distributions and their number is large, a particular MCMC algorithm may perform poorly and the resulting...... in the low correlation scenario where SG was the best strategy. The two LH proposals could not compete with any of the Gibbs sampling algorithms. In this study it was not possible to find an MCMC strategy that performs optimally across the range of target distributions and across all possible values...

  10. Canonical Correlational Models of Students’ Perceptions of Assessment Tasks, Motivational Orientations, and Learning Strategies

    Directory of Open Access Journals (Sweden)

    Hussain Alkharusi

    2013-01-01

    Full Text Available The present study aims at deriving correlational models of students' perceptions of assessment tasks, motivational orientations, and learning strategies using canonical analyses. Data were collected from 198 Omani tenth grade students. Results showed that high degrees of authenticity and transparency in assessment were associated with positive students' self-efficacy and task value. Also, high degrees of authenticity, transparency, and diversity in assessment were associated with a strong reliance on deep learning strategies; whereas a high degree of congruence with planned learning and a low degree of authenticity were associated with more reliance on surface learning strategies. Implications for classroom assessment practice and research were discussed.

  11. USING THE SWOT MODEL IN ESTABLISHING THE STRATEGY AT AUTOMOBILE DACIA GROUPE RENAULT COMPANY

    Directory of Open Access Journals (Sweden)

    Doruleţ GRĂDINARU

    2012-12-01

    Full Text Available SWOT analysis is a tool of the strategic management and it is used by the companies in the following situations: when they want to make ultimate decisions based on a complete analysis, in the strategic forecasting on three – five years, in the annual planning, when the company want a renewal or a radical change in its activity, or, each time when the company faces major difficulties which has to be solved as fast as possible. The SWOT model is also known as the Great strategy or the main strategy, being a part of the corporative strategies.

  12. Company Strategies for Responsible Research and Innovation (RRI: A Conceptual Model

    Directory of Open Access Journals (Sweden)

    Ibo van de Poel

    2017-11-01

    Full Text Available Responsible research and innovation (RRI has become an important topic in the academic community and in policy circles, but it has not yet been systematically included in the innovation process of companies. We discuss how companies can integrate RRI into their corporate social responsibility (CSR policies and business strategy. To this end, we developed a conceptual model that links a company’s RRI strategy to its context, and that helps to translate the RRI strategy into activities that result in RRI outcomes. We also propose a process for developing company-specific RRI key performance indicators (KPIs that can support companies to measure RRI outcomes.

  13. The CEV Model and Its Application in a Study of Optimal Investment Strategy

    Directory of Open Access Journals (Sweden)

    Aiyin Wang

    2014-01-01

    Full Text Available The constant elasticity of variance (CEV model is used to describe the price of the risky asset. Maximizing the expected utility relating to the Hamilton-Jacobi-Bellman (HJB equation which describes the optimal investment strategies, we obtain a partial differential equation. Applying the Legendre transform, we transform the equation into a dual problem and obtain an approximation solution and an optimal investment strategies for the exponential utility function.

  14. The structural model of pain, cognitive strategies, and negative emotions in functional gastrointestinal disorders

    Directory of Open Access Journals (Sweden)

    Mina Mazaheri

    2016-01-01

    Full Text Available Background: Patients with functional gastrointestinal disorders (FGIDs may use specific coping strategies. We intend to provide a mediating role of the relationship between pain (intensity and acceptance, cognitive emotion regulation strategies, and negative emotions in patients with FGIDs. Materials and Methods: Participants were 176 inpatients, all experiencing significant FGIDs symptomatology as confirmed by gastroenterologists. Patients completed data on cognitive emotion regulation questionnaire, short form of depression, anxiety, stress scale, chronic pain acceptance questionnaire-revised, and pain intensity scale. Data were analyzed using structural equation modeling method. Results: The pain intensity had significantly direct effect on cognitive emotion regulation strategies and indirect effect on negative emotions. Besides, the mediating role of negative emotions in the relationship between the strategies and pain acceptance were supported, whereas indirect relationships between pain intensity and acceptance through cognitive strategies were not confirmed. Conclusion: The results of the study emphasize the role of pain intensity in the development of negative emotions through cognitive strategies and the role of the strategies in pain acceptance through negative emotions. In fact, cognitive strategies to be related to pain and emotions.

  15. Complex dynamics and bifurcation analysis of host–parasitoid models with impulsive control strategy

    International Nuclear Information System (INIS)

    Yang, Jin; Tang, Sanyi; Tan, Yuanshun

    2016-01-01

    Highlights: • We develop novel host-parasitoid models with impulsive control strategy. • The effects of key parameters on the successful control have been addressed. • The complex dynamics and related biological significance are investigated. • The results between two types of host-parasitoid models have been discussed. - Abstract: In this paper, we propose and analyse two type host–parasitoid models with integrated pest management (IPM) interventions as impulsive control strategies. For fixed pulsed model, the threshold condition for the global stability of the host-eradication periodic solution is provided, and the effects of key parameters including the impulsive period, proportionate killing rate, instantaneous search rate, releasing constant, survival rate and the proportionate release rate on the threshold condition are discussed. Then latin hypercube sampling /partial rank correlation coefficients are used to carry out sensitivity analyses to determine the significance of each parameters. Further, bifurcation analyses are presented and the results show that coexistence of attractors existed for a wide range of parameters, and the switch-like transitions among these attractors indicate that varying dosages and frequencies of insecticide applications and numbers of parasitoid released are crucial for IPM strategy. For unfixed pulsed model, the results show that this model exists very complex dynamics and the host population can be controlled below ET, and it implies that the modelling methods are helpful for improving optimal strategies to design appropriate IPM.

  16. Learning Strategies Model to Enhance Thai Undergraduate Students' Self-Efficacy Beliefs in EIL Textual Reading Performance

    Science.gov (United States)

    Kakew, Jiraporn; Damnet, Anamai

    2017-01-01

    This classroom based research of a learning strategies model was designed to investigate its application in a mixed-ability classroom. The study built on Oxford's language learning strategies model (1990, 2001) and fulfilled it with rhetorical strategies to accommodate challenges encountered in the paradigm of English as an international language…

  17. A 3D Virtual Space for the E-Commerce Strategy Model

    OpenAIRE

    Gong Cheng; Changrui Yu; Kecheng Liu

    2014-01-01

    In recent years, innovative applications of electronic commerce (e-commerce) are facing the challenges of mobile commerce (m-commerce) and ubiquitous commerce (u-commerce). To address these challenges and improve the competitiveness of e-commerce, the three-dimensional e-commerce (3DEC) theory is proposed and a 3DEC business strategy model is built up in this study. The new conceptual 3DEC model incorporates the industrial environment analysis, SWOT analysis, and business model canvas (BMC). ...

  18. Evaluating the value chain model for service organisational strategy: International hotels.

    OpenAIRE

    Choi, Keetag.

    2000-01-01

    Strategic models like Porter's (1985) value chain have not been fully evaluated in the strategy literature and applied to all industries. To theoretically redefine the value chain technique, this research evaluates the value chain's use with various strategic issues by applying it to a specific aspect in the service field, namely the hotel industry. The study defines five key questions by which to evaluate a strategic model and the value chain model is examined using them. This research is a ...

  19. Hydrogeochemical site descriptive model - a strategy for the model development during site investigations

    Energy Technology Data Exchange (ETDEWEB)

    Smellie, John [Conterra AB, Uppsala (Sweden); Laaksoharju, Marcus [GeoPoint AB, Sollentuna (Sweden); Tullborg, Eva-Lena [Terralogica AB, Graabo (Sweden)

    2002-12-01

    In 2002, SKB commenced site characterisation investigations using deep boreholes at different sites. As an integral part of the planning work SKB has prepared a strategy to develop a Hydrogeochemical Site Descriptive Model; similar strategies have been developed for the other major geoscience disciplines. The main objectives of the Hydrogeochemical Site Descriptive Model are to describe the chemistry and distribution of the groundwater in the bedrock and overburden and the hydrogeochemical processes involved in its origin and evolution. This description is based primarily on measurements of the groundwater composition but incorporates the use of available geological and hydrogeological site descriptive models. The SKB hydrogeochemistry programme is planned to fulfil two basic requirements: 1) to provide representative and quality assured data for use as input parameter values in calculating long-term repository safety, and 2) to understand the present undisturbed hydrogeochemical conditions and how these conditions will change in the future. Parameter values for safety analysis include pH, Eh, S, SO{sub 4}, HCO{sub 3}, HPO{sub 4} and TDS (mainly cations), together with colloids, fulvic and humic acids, other organics, bacteria and nitrogen. These values will be used to characterise the groundwater environment at, above and below repository depths. In the hydrogeochemical site investigation programme the number and location of the sampling points will be constrained by: a) geology (e.g. topography, overburden types, bedrock structures etc), b) hydrogeology (e.g. groundwater recharge/discharge areas, residence times), c) reliability (e.g. undisturbed vs disturbed groundwater chemical conditions), and d) resources (e.g. number and type of samples, and also available personnel, may be restricted by budgetary and schedule concerns). Naturally a balance is required between these constraints and the scientific aims of the programme. The constraints should never

  20. Integrated Model to Assess Cloud Deployment Effectiveness When Developing an IT-strategy

    Science.gov (United States)

    Razumnikov, S.; Prankevich, D.

    2016-04-01

    Developing an IT-strategy of cloud deployment is a complex issue since even the stage of its formation necessitates revealing what applications will be the best possible to meet the requirements of a company business-strategy, evaluate reliability and safety of cloud providers and analyze staff satisfaction. A system of criteria, as well an integrated model to assess cloud deployment effectiveness is offered. The model makes it possible to identify what applications being at the disposal of a company, as well as new tools to be deployed are reliable and safe enough for implementation in the cloud environment. The data on practical use of the procedure to assess cloud deployment effectiveness by a provider of telecommunication services is presented. The model was used to calculate values of integral indexes of services to be assessed, then, ones, meeting the criteria and answering the business-strategy of a company, were selected.

  1. Assessment of Antimicrobial Treatment Strategies in Pig Production Using Mathematical Models

    DEFF Research Database (Denmark)

    Ahmad, Amais

    strategies. Dosing factors, along with the in vivo epidemiological parameters, govern the relation between resistance and antimicrobial use. Mathematical modeling and simulation techniques have been used over the past two decades to evaluate the effect of these factors on the development of resistance......, and are considered to be powerful tools in designing treatment strategies. The overall aim of the thesis was to develop an in vivo bacterial growth model to predict and assess the effect of dosing factor on resistance growth in order to optimize treatment strategies. Specific aims were to a) estimate pharmacodynamic...... concentration (MIC). These parameters along with MIC should be taken into account when studying the effect of antimicrobials on the bacterial growth. These parameters were used as an input to the in vivo growth model of multiple bacterial strains. For almost all treatments, high resistance levels were found...

  2. Assessment of Model Predictive and Adaptive Glucose Control Strategies for People with Type 1 Diabetes

    DEFF Research Database (Denmark)

    Boiroux, Dimitri; Duun-Henriksen, Anne Katrine; Schmidt, Signe

    2014-01-01

    This paper addresses overnight blood glucose stabilization in people with type 1 diabetes using a Model Predictive Controller (MPC). We use a control strategy based on an adaptive ARMAX model in which we use a Recursive Extended Least Squares (RELS) method to estimate parameters of the stochastic...... and reduce the risk of hypoglycemia. We test our control strategies on a virtual clinic of 100 randomly generated patients with a representative inter-subject variability. This virtual clinic is based on the Hovorka model. We consider the case where only half of the meal bolus is administered at mealtime......, and the case where the insulin sensitivity varies during the night. The simulation results demonstrate that the adaptive control strategy can reduce the risks of hypoglycemia and hyperglycemia during the night....

  3. Logical reasoning versus information processing in the dual-strategy model of reasoning.

    Science.gov (United States)

    Markovits, Henry; Brisson, Janie; de Chantal, Pier-Luc

    2017-01-01

    One of the major debates concerning the nature of inferential reasoning is between counterexample-based strategies such as mental model theory and statistical strategies underlying probabilistic models. The dual-strategy model, proposed by Verschueren, Schaeken, & d'Ydewalle (2005a, 2005b), which suggests that people might have access to both kinds of strategy has been supported by several recent studies. These have shown that statistical reasoners make inferences based on using information about premises in order to generate a likelihood estimate of conclusion probability. However, while results concerning counterexample reasoners are consistent with a counterexample detection model, these results could equally be interpreted as indicating a greater sensitivity to logical form. In order to distinguish these 2 interpretations, in Studies 1 and 2, we presented reasoners with Modus ponens (MP) inferences with statistical information about premise strength and in Studies 3 and 4, naturalistic MP inferences with premises having many disabling conditions. Statistical reasoners accepted the MP inference more often than counterexample reasoners in Studies 1 and 2, while the opposite pattern was observed in Studies 3 and 4. Results show that these strategies must be defined in terms of information processing, with no clear relations to "logical" reasoning. These results have additional implications for the underlying debate about the nature of human reasoning. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  4. Modeling of optimization strategies in the incremental CNC sheet metal forming process

    International Nuclear Information System (INIS)

    Bambach, M.; Hirt, G.; Ames, J.

    2004-01-01

    Incremental CNC sheet forming (ISF) is a relatively new sheet metal forming process for small batch production and prototyping. In ISF, a blank is shaped by the CNC movements of a simple tool in combination with a simplified die. The standard forming strategies in ISF entail two major drawbacks: (i) the inherent forming kinematics set limits on the maximum wall angle that can be formed with ISF. (ii) since elastic parts of the imposed deformation can currently not be accounted for in CNC code generation, the standard strategies can lead to undesired deviations between the target and the sample geometry.Several enhancements have recently been put forward to overcome the above limitations, among them a multistage forming strategy to manufacture steep flanges, and a correction algorithm to improve the geometric accuracy. Both strategies have been successful in improving the forming of simple parts. However, the high experimental effort to empirically optimize the tool paths motivates the use of process modeling techniques.This paper deals with finite element modeling of the ISF process. In particular, the outcome of different multistage strategies is modeled and compared to collated experimental results regarding aspects such as sheet thickness and the onset of wrinkling. Moreover, the feasibility of modeling the geometry of a part is investigated as this is of major importance with respect to optimizing the geometric accuracy. Experimental validation is achieved by optical deformation measurement that gives the local displacements and strains of the sheet during forming as benchmark quantities for the simulation

  5. Variable speed limit strategies analysis with link transmission model on urban expressway

    Science.gov (United States)

    Li, Shubin; Cao, Danni

    2018-02-01

    The variable speed limit (VSL) is a kind of active traffic management method. Most of the strategies are used in the expressway traffic flow control in order to ensure traffic safety. However, the urban expressway system is the main artery, carrying most traffic pressure. It has similar traffic characteristics with the expressways between cities. In this paper, the improved link transmission model (LTM) combined with VSL strategies is proposed, based on the urban expressway network. The model can simulate the movement of the vehicles and the shock wave, and well balance the relationship between the amount of calculation and accuracy. Furthermore, the optimal VSL strategy can be proposed based on the simulation method. It can provide management strategies for managers. Finally, a simple example is given to illustrate the model and method. The selected indexes are the average density, the average speed and the average flow on the traffic network in the simulation. The simulation results show that the proposed model and method are feasible. The VSL strategy can effectively alleviate traffic congestion in some cases, and greatly promote the efficiency of the transportation system.

  6. MODEL OF PROVIDING WITH DEVELOPMENT STRATEGY FOR INFORMATION TECHNOLOGIES IN AN ORGANIZATION

    Directory of Open Access Journals (Sweden)

    A. A. Kuzkin

    2015-03-01

    Full Text Available Subject of research. The paper presents research and instructional tools for assessment of providing with the development strategy for information technologies in an organization. Method. The corresponding assessment model is developed which takes into consideration IT-processes equilibrium according to selected efficiency factors of information technologies application. Basic results. The model peculiarity resides in applying neuro-fuzzy approximators where the conclusion is drawn upon fuzzy logic, and membership functions are adjusted through the use of neural networks. For the adequacy testing of the suggested model, due diligence result analysis has been carried out for the IT-strategy executed in the “Navigator” group of companies at the stage of implementation and support of new technologies and production methods. Data visualization with a circle diagram is applied for the comparative evaluation of the analysis results. The chosen model adequacy is proved by the agreement between predictive assessments for IT-strategy performance targets derived by means of the fuzzy cognitive model over 12 months planning horizon and the real values of these targets upon the expiry of the given planning term. Practical significance. The developed model application gives the possibility to solve the problem of sustainability assessment for the process of providing the required IT-strategy realization level based upon the fuzzy cognitive map analysis and to reveal IT-objectives changing tendencies for an organization over the stated planning interval.

  7. Emotion regulation strategies: procedure modeling of J. Gross and cultural activity approach

    Directory of Open Access Journals (Sweden)

    Elena I. Pervichko

    2015-03-01

    Full Text Available The first part of this paper argued the desirability of structural-dynamic model of emotion regulation in the theoretical and methodological framework of cultural activity paradigm with the construction of a psychologically-based typology of emotion regulation strategies in norm and pathology, and also psychological mechanisms enabling the regulation of emotions. This conclusion was based on the analysis of the basic concepts and paradigms in which the issue of emotion regulation is studied: cognitive and psychoanalytic approaches, concept and emotional development of emotional intelligence, cultural activity approach. The paper considers the procedure model of emotion regulation by J. Gross, identifies emotion regulation strategies and evaluates their effectiveness. The possibilities and limitations of the model. Based on the review of the today research the conclusion is arrived at that the existing labels on a wide range of regulatory strategies remain an open issue.The author’s definition of emotion regulation is drawn. Emotion regulation is deemed as a set of mental processes, psychological mechanisms and regulatory strategies that people use to preserve the capacity for productive activities in a situation of emotional stress; to ensure optimal impulse control and emotions; to maintain the excitement at the optimum level. The second part of this paper provides the general description of emotion regulation strategies, the approach to their typology, the psychological mechanisms of emotion regulation that lie in the basis of this typology, i.e. the main elements of the structural-dynamic model of emotion regulation. The work shows theoretical and methodological efficacy of empirical significance of signs and symbols and also personal reflection. The diagnostic system to allow empirically identify a wide range of emotion regulation strategies is suggested. The psychological mechanisms used by the subject to solve the problem of emotional

  8. Modelling and operation strategies of DLR's large scale thermocline test facility (TESIS)

    Science.gov (United States)

    Odenthal, Christian; Breidenbach, Nils; Bauer, Thomas

    2017-06-01

    In this work an overview of the TESIS:store thermocline test facility and its current construction status will be given. Based on this, the TESIS:store facility using sensible solid filler material is modelled with a fully transient model, implemented in MATLAB®. Results in terms of the impact of filler site and operation strategies will be presented. While low porosity and small particle diameters for the filler material are beneficial, operation strategy is one key element with potential for optimization. It is shown that plant operators have to ponder between utilization and exergetic efficiency. Different durations of the charging and discharging period enable further potential for optimizations.

  9. A speed guidance strategy for multiple signalized intersections based on car-following model

    Science.gov (United States)

    Tang, Tie-Qiao; Yi, Zhi-Yan; Zhang, Jian; Wang, Tao; Leng, Jun-Qiang

    2018-04-01

    Signalized intersection has great roles in urban traffic system. The signal infrastructure and the driving behavior near the intersection are paramount factors that have significant impacts on traffic flow and energy consumption. In this paper, a speed guidance strategy is introduced into a car-following model to study the driving behavior and the fuel consumption in a single-lane road with multiple signalized intersections. The numerical results indicate that the proposed model can reduce the fuel consumption and the average stop times. The findings provide insightful guidance for the eco-driving strategies near the signalized intersections.

  10. Thermal Site Descriptive Model. A strategy for the model development during site investigations. Version 1.0

    International Nuclear Information System (INIS)

    Sundberg, Jan

    2003-04-01

    Site investigations are in progress for the siting of a deep repository for spent nuclear fuel. As part of the planning work, strategies are developed for site descriptive modelling regarding different disciplines, amongst them the thermal conditions. The objective of the strategy for a thermal site descriptive model is to guide the practical implementation of evaluating site specific data during the site investigations. It is understood that further development may be needed. The model describes the thermal properties and other thermal parameters of intact rock, fractures and fracture zones, and of the rock mass. The methodology is based on estimation of thermal properties of intact rock and discontinuities, using both empirical and theoretical/numerical approaches, and estimation of thermal processes using mathematical modelling. The methodology will be used and evaluated for the thermal site descriptive modelling at the Aespoe Hard Rock Laboratory

  11. Deriving metabolic engineering strategies from genome-scale modeling with flux ratio constraints.

    Science.gov (United States)

    Yen, Jiun Y; Nazem-Bokaee, Hadi; Freedman, Benjamin G; Athamneh, Ahmad I M; Senger, Ryan S

    2013-05-01

    Optimized production of bio-based fuels and chemicals from microbial cell factories is a central goal of systems metabolic engineering. To achieve this goal, a new computational method of using flux balance analysis with flux ratios (FBrAtio) was further developed in this research and applied to five case studies to evaluate and design metabolic engineering strategies. The approach was implemented using publicly available genome-scale metabolic flux models. Synthetic pathways were added to these models along with flux ratio constraints by FBrAtio to achieve increased (i) cellulose production from Arabidopsis thaliana; (ii) isobutanol production from Saccharomyces cerevisiae; (iii) acetone production from Synechocystis sp. PCC6803; (iv) H2 production from Escherichia coli MG1655; and (v) isopropanol, butanol, and ethanol (IBE) production from engineered Clostridium acetobutylicum. The FBrAtio approach was applied to each case to simulate a metabolic engineering strategy already implemented experimentally, and flux ratios were continually adjusted to find (i) the end-limit of increased production using the existing strategy, (ii) new potential strategies to increase production, and (iii) the impact of these metabolic engineering strategies on product yield and culture growth. The FBrAtio approach has the potential to design "fine-tuned" metabolic engineering strategies in silico that can be implemented directly with available genomic tools. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Using the Logistic Regression model in supporting decisions of establishing marketing strategies

    Directory of Open Access Journals (Sweden)

    Cristinel CONSTANTIN

    2015-12-01

    Full Text Available This paper is about an instrumental research regarding the using of Logistic Regression model for data analysis in marketing research. The decision makers inside different organisation need relevant information to support their decisions regarding the marketing strategies. The data provided by marketing research could be computed in various ways but the multivariate data analysis models can enhance the utility of the information. Among these models we can find the Logistic Regression model, which is used for dichotomous variables. Our research is based on explanation the utility of this model and interpretation of the resulted information in order to help practitioners and researchers to use it in their future investigations

  13. Stochastic models for the Trojan Y-Chromosome eradication strategy of an invasive species.

    Science.gov (United States)

    Wang, Xueying; Walton, Jay R; Parshad, Rana D

    2016-01-01

    The Trojan Y-Chromosome (TYC) strategy, an autocidal genetic biocontrol method, has been proposed to eliminate invasive alien species. In this work, we develop a Markov jump process model for this strategy, and we verify that there is a positive probability for wild-type females going extinct within a finite time. Moreover, when sex-reversed Trojan females are introduced at a constant population size, we formulate a stochastic differential equation (SDE) model as an approximation to the proposed Markov jump process model. Using the SDE model, we investigate the probability distribution and expectation of the extinction time of wild-type females by solving Kolmogorov equations associated with these statistics. The results indicate how the probability distribution and expectation of the extinction time are shaped by the initial conditions and the model parameters.

  14. Influence of the management strategy model on estimating water system performance under climate change

    Science.gov (United States)

    Francois, Baptiste; Hingray, Benoit; Creutin, Jean-Dominique; Hendrickx, Frederic

    2015-04-01

    The performance of water systems used worldwide for the management of water resources is expected to be influenced by future changes in regional climates and water uses. Anticipating possible performance changes of a given system requires a modeling chain simulating its management. Operational management is usually not trivial especially when several conflicting objectives have to be accounted for. Management models are therefore often a crude representation of the real system and they only approximate its performance. Estimated performance changes are expected to depend on the management model used, but this is often not assessed. This communication analyzes the influence of the management strategy representation on the performance of an Alpine reservoir (Serre-Ponçon, South-East of France) for which irrigation supply, hydropower generation and recreational activities are the main objectives. We consider three ways to construct the strategy named as clear-, short- and far-sighted management. They are based on different forecastability degrees of seasonal inflows into the reservoir. The strategies are optimized using a Dynamic Programming algorithm (deterministic for clear-sighted and implicit stochastic for short- and far-sighted). System performance is estimated for an ensemble of future hydro-meteorological projections obtained in the RIWER2030 research project (http://www.lthe.fr/RIWER2030/) from a suite of climate experiments from the EU - ENSEMBLES research project. Our results show that changes in system performance is much more influenced by changes in hydro-meteorological variables than by the choice of strategy modeling. They also show that a simple strategy representation (i.e. clear-sighted management) leads to similar estimates of performance modifications than those obtained with a representation supposedly closer to real world (i.e. the far-sighted management). The Short-Sighted management approach lead to significantly different results, especially

  15. A characteristic study of CCF modeling techniques and optimization of CCF defense strategies

    International Nuclear Information System (INIS)

    Kim, Min Chull

    2000-02-01

    Common Cause Failures (CCFs ) are among the major contributors to risk and core damage frequency (CDF ) from operating nuclear power plants (NPPs ). Our study on CCF focused on the following aspects : 1) a characteristic study on the CCF modeling techniques and 2) development of the optimal CCF defense strategy. Firstly, the characteristics of CCF modeling techniques were studied through sensitivity study of CCF occurrence probability upon system redundancy. The modeling techniques considered in this study include those most widely used worldwide, i.e., beta factor, MGL, alpha factor, and binomial failure rate models. We found that MGL and alpha factor models are essentially identical in terms of the CCF probability. Secondly, in the study for CCF defense, the various methods identified in the previous studies for defending against CCF were classified into five different categories. Based on these categories, we developed a generic method by which the optimal CCF defense strategy can be selected. The method is not only qualitative but also quantitative in nature: the selection of the optimal strategy among candidates is based on the use of analytic hierarchical process (AHP). We applied this method to two motor-driven valves for containment sump isolation in Ulchin 3 and 4 nuclear power plants. The result indicates that the method for developing an optimal CCF defense strategy is effective

  16. Programming strategy for efficient modeling of dynamics in a population of heterogeneous cells.

    Science.gov (United States)

    Hald, Bjørn Olav; Garkier Hendriksen, Morten; Sørensen, Preben Graae

    2013-05-15

    Heterogeneity is a ubiquitous property of biological systems. Even in a genetically identical population of a single cell type, cell-to-cell differences are observed. Although the functional behavior of a given population is generally robust, the consequences of heterogeneity are fairly unpredictable. In heterogeneous populations, synchronization of events becomes a cardinal problem-particularly for phase coherence in oscillating systems. The present article presents a novel strategy for construction of large-scale simulation programs of heterogeneous biological entities. The strategy is designed to be tractable, to handle heterogeneity and to handle computational cost issues simultaneously, primarily by writing a generator of the 'model to be simulated'. We apply the strategy to model glycolytic oscillations among thousands of yeast cells coupled through the extracellular medium. The usefulness is illustrated through (i) benchmarking, showing an almost linear relationship between model size and run time, and (ii) analysis of the resulting simulations, showing that contrary to the experimental situation, synchronous oscillations are surprisingly hard to achieve, underpinning the need for tools to study heterogeneity. Thus, we present an efficient strategy to model the biological heterogeneity, neglected by ordinary mean-field models. This tool is well posed to facilitate the elucidation of the physiologically vital problem of synchronization. The complete python code is available as Supplementary Information. bjornhald@gmail.com or pgs@kiku.dk Supplementary data are available at Bioinformatics online.

  17. Modelling and Optimal Control of Typhoid Fever Disease with Cost-Effective Strategies.

    Science.gov (United States)

    Tilahun, Getachew Teshome; Makinde, Oluwole Daniel; Malonza, David

    2017-01-01

    We propose and analyze a compartmental nonlinear deterministic mathematical model for the typhoid fever outbreak and optimal control strategies in a community with varying population. The model is studied qualitatively using stability theory of differential equations and the basic reproductive number that represents the epidemic indicator is obtained from the largest eigenvalue of the next-generation matrix. Both local and global asymptotic stability conditions for disease-free and endemic equilibria are determined. The model exhibits a forward transcritical bifurcation and the sensitivity analysis is performed. The optimal control problem is designed by applying Pontryagin maximum principle with three control strategies, namely, the prevention strategy through sanitation, proper hygiene, and vaccination; the treatment strategy through application of appropriate medicine; and the screening of the carriers. The cost functional accounts for the cost involved in prevention, screening, and treatment together with the total number of the infected persons averted. Numerical results for the typhoid outbreak dynamics and its optimal control revealed that a combination of prevention and treatment is the best cost-effective strategy to eradicate the disease.

  18. A robust model predictive control strategy for improving the control performance of air-conditioning systems

    International Nuclear Information System (INIS)

    Huang Gongsheng; Wang Shengwei; Xu Xinhua

    2009-01-01

    This paper presents a robust model predictive control strategy for improving the supply air temperature control of air-handling units by dealing with the associated uncertainties and constraints directly. This strategy uses a first-order plus time-delay model with uncertain time-delay and system gain to describe air-conditioning process of an air-handling unit usually operating at various weather conditions. The uncertainties of the time-delay and system gain, which imply the nonlinearities and the variable dynamic characteristics, are formulated using an uncertainty polytope. Based on this uncertainty formulation, an offline LMI-based robust model predictive control algorithm is employed to design a robust controller for air-handling units which can guarantee a good robustness subject to uncertainties and constraints. The proposed robust strategy is evaluated in a dynamic simulation environment of a variable air volume air-conditioning system in various operation conditions by comparing with a conventional PI control strategy. The robustness analysis of both strategies under different weather conditions is also presented.

  19. An Assessment for A Filtered Containment Venting Strategy Using Decision Tree Models

    International Nuclear Information System (INIS)

    Shin, Hoyoung; Jae, Moosung

    2016-01-01

    In this study, a probabilistic assessment of the severe accident management strategy through a filtered containment venting system was performed by using decision tree models. In Korea, the filtered containment venting system has been installed for the first time in Wolsong unit 1 as a part of Fukushima follow-up steps, and it is planned to be applied gradually for all the remaining reactors. Filtered containment venting system, one of severe accident countermeasures, prevents a gradual pressurization of the containment building exhausting noncondensable gas and vapor to the outside of the containment building. In this study, a probabilistic assessment of the filtered containment venting strategy, one of the severe accident management strategies, was performed by using decision tree models. Containment failure frequencies of each decision were evaluated by the developed decision tree model. The optimum accident management strategies were evaluated by comparing the results. Various strategies in severe accident management guidelines (SAMG) could be improved by utilizing the methodology in this study and the offsite risk analysis methodology

  20. An Assessment for A Filtered Containment Venting Strategy Using Decision Tree Models

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Hoyoung; Jae, Moosung [Hanyang University, Seoul (Korea, Republic of)

    2016-10-15

    In this study, a probabilistic assessment of the severe accident management strategy through a filtered containment venting system was performed by using decision tree models. In Korea, the filtered containment venting system has been installed for the first time in Wolsong unit 1 as a part of Fukushima follow-up steps, and it is planned to be applied gradually for all the remaining reactors. Filtered containment venting system, one of severe accident countermeasures, prevents a gradual pressurization of the containment building exhausting noncondensable gas and vapor to the outside of the containment building. In this study, a probabilistic assessment of the filtered containment venting strategy, one of the severe accident management strategies, was performed by using decision tree models. Containment failure frequencies of each decision were evaluated by the developed decision tree model. The optimum accident management strategies were evaluated by comparing the results. Various strategies in severe accident management guidelines (SAMG) could be improved by utilizing the methodology in this study and the offsite risk analysis methodology.

  1. Diagnosing the impact of alternative calibration strategies on coupled hydrologic models

    Science.gov (United States)

    Smith, T. J.; Perera, C.; Corrigan, C.

    2017-12-01

    Hydrologic models represent a significant tool for understanding, predicting, and responding to the impacts of water on society and society on water resources and, as such, are used extensively in water resources planning and management. Given this important role, the validity and fidelity of hydrologic models is imperative. While extensive focus has been paid to improving hydrologic models through better process representation, better parameter estimation, and better uncertainty quantification, significant challenges remain. In this study, we explore a number of competing model calibration scenarios for simple, coupled snowmelt-runoff models to better understand the sensitivity / variability of parameterizations and its impact on model performance, robustness, fidelity, and transferability. Our analysis highlights the sensitivity of coupled snowmelt-runoff model parameterizations to alterations in calibration approach, underscores the concept of information content in hydrologic modeling, and provides insight into potential strategies for improving model robustness / fidelity.

  2. Towards a benchmark simulation model for plant-wide control strategy performance evaluation of WWTPs

    DEFF Research Database (Denmark)

    Jeppsson, Ulf; Rosen, Christian; Alex, Jens

    2006-01-01

    The COST/IWA benchmark simulation model has been available for seven years. Its primary purpose has been to create a platform for control strategy benchmarking of activated sludge processes. The fact that the benchmark has resulted in more than 100 publications, not only in Europe but also...... worldwide, demonstrates the interest in such a tool within the research community In this paper, an extension of the benchmark simulation model no 1 (BSM1) is proposed. This extension aims at facilitating control strategy development and performance evaluation at a plant-wide level and, consequently...... the changes, the evaluation period has been extended to one year. A prolonged evaluation period allows for long-term control strategies to be assessed and enables the use of control handles that cannot be evaluated in a realistic fashion in the one-week BSM1 evaluation period. In the paper, the extended plant...

  3. Energy Management Strategy Based on the Driving Cycle Model for Plugin Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Xiaoling Fu

    2014-01-01

    Full Text Available The energy management strategy (EMS for a plugin hybrid electric vehicle (PHEV is proposed based on the driving cycle model and dynamic programming (DP algorithm. A driving cycle model is constructed by collecting and processing the driving data of a certain school bus. The state of charge (SOC profile can be obtained by the DP algorithm for the whole driving cycle. In order to optimize the energy management strategy in the hybrid power system, the optimal motor torque control sequence can be calculated using the DP algorithm for the segments between the traffic intersections. Compared with the traditional charge depleting-charge sustaining (CDCS strategy, the test results on the ADVISOR platform show a significant improvement in fuel consumption using the EMS proposed in this paper.

  4. Enhancing conflict negotiation strategies of adolescents with autism spectrum disorder using video modeling.

    Science.gov (United States)

    Hochhauser, M; Weiss, P L; Gal, E

    2018-01-01

    Adolescents with autism spectrum disorder (ASD) have particular difficulty in negotiating conflict. A randomized control trial (RCT) was carried out to determine whether the negotiation strategies of adolescents with ASD would be enhanced via a 6-week intervention based on a video modeling application. Adolescents with ASD, aged 12-18 years, were randomly divided into an intervention group (n = 36) and a non-treatment control group (n = 25). Participants' negotiating strategies prior to and following the intervention were measured using the Five Factor Negotiation Scale (FFNS; Nakkula & Nikitopoulos, 1999) and the ConflicTalk questionnaire (Kimsey & Fuller, 2003). The results suggest that video modeling is an effective intervention for improving and maintaining conflict negotiation strategies of adolescents with ASD.

  5. Intervention Strategies Based on Information-Motivation-Behavioral Skills Model for Health Behavior Change: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Sun Ju Chang, RN, PhD

    2014-09-01

    Conclusion: This review indicates the potential strength of the IMB model as a theoretical framework to develop behavioral interventions. The specific integration strategies delineated for each construct of the model can be utilized to design model-based interventions.

  6. Multi-infill strategy for kriging models used in variable fidelity optimization

    Directory of Open Access Journals (Sweden)

    Chao SONG

    2018-03-01

    Full Text Available In this paper, a computationally efficient optimization method for aerodynamic design has been developed. The low-fidelity model and the multi-infill strategy are utilized in this approach. Low-fidelity data is employed to provide a good global trend for model prediction, and multiple sample points chosen by different infill criteria in each updating cycle are used to enhance the exploitation and exploration ability of the optimization approach. Take the advantages of low-fidelity model and the multi-infill strategy, and no initial sample for the high-fidelity model is needed. This approach is applied to an airfoil design case and a high-dimensional wing design case. It saves a large number of high-fidelity function evaluations for initial model construction. What’s more, faster reduction of an aerodynamic function is achieved, when compared to ordinary kriging using the multi-infill strategy and variable-fidelity model using single infill criterion. The results indicate that the developed approach has a promising application to efficient aerodynamic design when high-fidelity analyses are involved. Keywords: Aerodynamics, Infill criteria, Kriging models, Multi-infill, Optimization

  7. Statistical power of model selection strategies for genome-wide association studies.

    Directory of Open Access Journals (Sweden)

    Zheyang Wu

    2009-07-01

    Full Text Available Genome-wide association studies (GWAS aim to identify genetic variants related to diseases by examining the associations between phenotypes and hundreds of thousands of genotyped markers. Because many genes are potentially involved in common diseases and a large number of markers are analyzed, it is crucial to devise an effective strategy to identify truly associated variants that have individual and/or interactive effects, while controlling false positives at the desired level. Although a number of model selection methods have been proposed in the literature, including marginal search, exhaustive search, and forward search, their relative performance has only been evaluated through limited simulations due to the lack of an analytical approach to calculating the power of these methods. This article develops a novel statistical approach for power calculation, derives accurate formulas for the power of different model selection strategies, and then uses the formulas to evaluate and compare these strategies in genetic model spaces. In contrast to previous studies, our theoretical framework allows for random genotypes, correlations among test statistics, and a false-positive control based on GWAS practice. After the accuracy of our analytical results is validated through simulations, they are utilized to systematically evaluate and compare the performance of these strategies in a wide class of genetic models. For a specific genetic model, our results clearly reveal how different factors, such as effect size, allele frequency, and interaction, jointly affect the statistical power of each strategy. An example is provided for the application of our approach to empirical research. The statistical approach used in our derivations is general and can be employed to address the model selection problems in other random predictor settings. We have developed an R package markerSearchPower to implement our formulas, which can be downloaded from the

  8. Random sampling or geostatistical modelling? Choosing between design-based and model-based sampling strategies for soil (with discussion)

    NARCIS (Netherlands)

    Brus, D.J.; Gruijter, de J.J.

    1997-01-01

    Classical sampling theory has been repeatedly identified with classical statistics which assumes that data are identically and independently distributed. This explains the switch of many soil scientists from design-based sampling strategies, based on classical sampling theory, to the model-based

  9. Martian methane plume models for defining Mars rover methane source search strategies

    Science.gov (United States)

    Nicol, Christopher; Ellery, Alex; Lynch, Brian; Cloutis, Ed

    2018-07-01

    The detection of atmospheric methane on Mars implies an active methane source. This introduces the possibility of a biotic source with the implied need to determine whether the methane is indeed biotic in nature or geologically generated. There is a clear need for robotic algorithms which are capable of manoeuvring a rover through a methane plume on Mars to locate its source. We explore aspects of Mars methane plume modelling to reveal complex dynamics characterized by advection and diffusion. A statistical analysis of the plume model has been performed and compared to analyses of terrestrial plume models. Finally, we consider a robotic search strategy to find a methane plume source. We find that gradient-based techniques are ineffective, but that more sophisticated model-based search strategies are unlikely to be available in near-term rover missions.

  10. Enhancing English Language Planning Strategy Using a WebQuest Model

    Science.gov (United States)

    Al-Sayed, Rania Kamal Muhammad; Abdel-Haq, Eman Muhammad; El-Deeb, Mervat Abou-Bakr; Ali, Mahsoub Abdel-Sadeq

    2016-01-01

    The present study aimed at developing English language planning strategy of second year distinguished governmental language preparatory school pupils using the a WebQuest model. Fifty participants from second year at Hassan Abu-Bakr Distinguished Governmental Language School at Al-Qanater Al-Khairia (Qalubia Governorate) were randomly assigned…

  11. Exploring the Benefits of Teacher-Modeling Strategies Integrated into Career and Technical Education

    Science.gov (United States)

    Cathers, Thomas J., Sr.

    2013-01-01

    This case study examined how career and technical education classes function using multiple instructional modeling strategies integrated into vocational and technical training environments. Seven New Jersey public school technical teachers received an introductory overview of the investigation and participated by responding to 10 open-end…

  12. Economic modeling using evolutionary algorithms : the effect of binary encoding of strategies

    NARCIS (Netherlands)

    Waltman, L.R.; Eck, van N.J.; Dekker, Rommert; Kaymak, U.

    2011-01-01

    We are concerned with evolutionary algorithms that are employed for economic modeling purposes. We focus in particular on evolutionary algorithms that use a binary encoding of strategies. These algorithms, commonly referred to as genetic algorithms, are popular in agent-based computational economics

  13. Boundedly rational learning and heterogeneous trading strategies with hybrid neuro-fuzzy models

    NARCIS (Netherlands)

    Bekiros, S.D.

    2009-01-01

    The present study deals with heterogeneous learning rules in speculative markets where heuristic strategies reflect the rules-of-thumb of boundedly rational investors. The major challenge for "chartists" is the development of new models that would enhance forecasting ability particularly for time

  14. Strategies for Testing Statistical and Practical Significance in Detecting DIF with Logistic Regression Models

    Science.gov (United States)

    Fidalgo, Angel M.; Alavi, Seyed Mohammad; Amirian, Seyed Mohammad Reza

    2014-01-01

    This study examines three controversial aspects in differential item functioning (DIF) detection by logistic regression (LR) models: first, the relative effectiveness of different analytical strategies for detecting DIF; second, the suitability of the Wald statistic for determining the statistical significance of the parameters of interest; and…

  15. Designing efficient nitrous oxide sampling strategies in agroecosystems using simulation models

    Science.gov (United States)

    Debasish Saha; Armen R. Kemanian; Benjamin M. Rau; Paul R. Adler; Felipe Montes

    2017-01-01

    Annual cumulative soil nitrous oxide (N2O) emissions calculated from discrete chamber-based flux measurements have unknown uncertainty. We used outputs from simulations obtained with an agroecosystem model to design sampling strategies that yield accurate cumulative N2O flux estimates with a known uncertainty level. Daily soil N2O fluxes were simulated for Ames, IA (...

  16. Factor Analysis of the HEW National Strategy for Youth Development Model's Community Program Impact Scales.

    Science.gov (United States)

    Truckenmiller, James L.

    The former HEW (Health, Education, and Welfare) National Strategy for Youth Development Model proposed a community-based program to promote positive youth development and to prevent delinquency through a sequence of youth needs assessments, needs-targeted programs, and program impact evaluation. HEW Community Program Impact Scales data obtained…

  17. Effect of control strategies on the persistence of fish-borne zoonotic trematodes: A modelling approach

    NARCIS (Netherlands)

    Boerlage, A.S.; Graat, E.A.M.; Verreth, J.A.J.; Jong, de M.C.M.

    2013-01-01

    Fish-borne Zoonotic Trematodes (FZTs) are a risk to human health and need to be controlled. A mathematical model was developed to give insight into how and to what extent control strategies change the dynamics of FZTs on integrated agriculture–aquaculture farms. The reproduction ratio R evaluates

  18. Effective Strategy Formation Models for Inventory Management under the Conditions of Uncertainty

    Science.gov (United States)

    Kosorukov, Oleg Anatolyevich; Sviridova, Olga Alexandrovna

    2015-01-01

    The article deals with the problem of modeling the commodity flows management of a trading company under the conditions of uncertain demand and long supply. The Author presents an analysis of modifications of diversified inventory management system with random demand, for which one can find the optimal inventory control strategies, including those…

  19. Uncertainty and sensitivity analysis of control strategies using the benchmark simulation model No1 (BSM1)

    DEFF Research Database (Denmark)

    Flores-Alsina, Xavier; Rodriguez-Roda, Ignasi; Sin, Gürkan

    2009-01-01

    The objective of this paper is to perform an uncertainty and sensitivity analysis of the predictions of the Benchmark Simulation Model (BSM) No. 1, when comparing four activated sludge control strategies. The Monte Carlo simulation technique is used to evaluate the uncertainty in the BSM1 predict...

  20. An Analytical Framework for Evaluating E-Commerce Business Models and Strategies.

    Science.gov (United States)

    Lee, Chung-Shing

    2001-01-01

    Considers electronic commerce as a paradigm shift, or a disruptive innovation, and presents an analytical framework based on the theories of transaction costs and switching costs. Topics include business transformation process; scale effect; scope effect; new sources of revenue; and e-commerce value creation model and strategy. (LRW)

  1. Strategies for Controlling Item Exposure in Computerized Adaptive Testing with the Generalized Partial Credit Model

    Science.gov (United States)

    Davis, Laurie Laughlin

    2004-01-01

    Choosing a strategy for controlling item exposure has become an integral part of test development for computerized adaptive testing (CAT). This study investigated the performance of six procedures for controlling item exposure in a series of simulated CATs under the generalized partial credit model. In addition to a no-exposure control baseline…

  2. Rapid E-learning Development Strategies and a Multimedia Project Design Model

    Science.gov (United States)

    Sözcü, Ömer Faruk; Ipek, Ismail

    2014-01-01

    The purpose of the study is to discuss e-learning design strategies which can be used for multimedia projects as a design model. Recent advances in instructional technologies have been found to be very important in the design of training courses by using rapid instructional design (ID) approaches. The approaches were developed to use in training…

  3. Modelling the transport system in China and evaluating the current strategies towards the sustainable transport development

    DEFF Research Database (Denmark)

    Liu, W.; Lund, H.; Mathiesen, B.V.

    2013-01-01

    in China. With this purpose in mind, a Chinese transport model has been created and three current transport strategies which are high speed railway (HSR), urban rail transit (URT) and electric vehicle (EV) were evaluated together with a reference transport system in 2020. As conservative results, 13...

  4. Hydrogeological Site Descriptive Model - a strategy for its development during Site Investigations

    Energy Technology Data Exchange (ETDEWEB)

    Rhen, Ingvar [SWECO VIAK AB, Goeteborg (Sweden); Follin, Sven [SF GeoLogic AB, Stockholm (Sweden); Hermanson, Jan [Golder Associates, Stockholm (Sweden)

    2003-04-01

    The report is to present a strategy for the development of the Site Descriptive Hydrogeological Model within the SKB Site Investigation Programme. The report, and similar reports from the Geology, Rock Mechanics, Thermal properties, Hydrogeochemistry, Transport Properties and Surface Ecosystem disciplines are intended to guide SKB Site Descriptive Modelling but also to provide the authorities with an overview of how the modelling should be performed. Thus the objectives of this report are to: provide guidelines for the modelling of different sites resulting in consistent handling of modelling issues during the Site Investigations, provide a structure for the modelling sequence that is suitable for the establishment of a Site Descriptive model and provide some necessary details that should be considered in a Site Descriptive model.

  5. Hydrogeological Site Descriptive Model - a strategy for its development during Site Investigations

    International Nuclear Information System (INIS)

    Rhen, Ingvar; Follin, Sven; Hermanson, Jan

    2003-04-01

    The report is to present a strategy for the development of the Site Descriptive Hydrogeological Model within the SKB Site Investigation Programme. The report, and similar reports from the Geology, Rock Mechanics, Thermal properties, Hydrogeochemistry, Transport Properties and Surface Ecosystem disciplines are intended to guide SKB Site Descriptive Modelling but also to provide the authorities with an overview of how the modelling should be performed. Thus the objectives of this report are to: provide guidelines for the modelling of different sites resulting in consistent handling of modelling issues during the Site Investigations, provide a structure for the modelling sequence that is suitable for the establishment of a Site Descriptive model and provide some necessary details that should be considered in a Site Descriptive model

  6. MARKET ENTRY STRATEGIES TO EMERGING MARKETS: A CONCEPTUAL MODEL OF TURNKEY PROJECT DEVELOPMENT

    OpenAIRE

    Bistra Vassileva; Miroslav Nikolov

    2016-01-01

    The main purpose of the paper is to analyse the international market entry strategies in the light of globalisation processes and to propose a conceptual model of turnkey projects as market entry mode. The specific research objectives are as follows: 1. to develop an integrated framework of the turnkey marketing process as a conceptual model; 2. to analyse BRICS countries as potential host countries for turnkey projects implementation; 3. to assess potential implications of proposed concep...

  7. A Traction Control Strategy with an Efficiency Model in a Distributed Driving Electric Vehicle

    OpenAIRE

    Lin, Cheng; Cheng, Xingqun

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the tw...

  8. A model-based eco-routing strategy for electric vehicles in large urban networks

    OpenAIRE

    De Nunzio , Giovanni; Thibault , Laurent; Sciarretta , Antonio

    2016-01-01

    International audience; A novel eco-routing navigation strategy and energy consumption modeling approach for electric vehicles are presented in this work. Speed fluctuations and road network infrastructure have a large impact on vehicular energy consumption. Neglecting these effects may lead to large errors in eco-routing navigation, which could trivially select the route with the lowest average speed. We propose an energy consumption model that considers both accelerations and impact of the ...

  9. Model-Based Optimization of Velocity Strategy for Lightweight Electric Racing Cars

    Directory of Open Access Journals (Sweden)

    Mirosław Targosz

    2018-01-01

    Full Text Available The article presents a method for optimizing driving strategies aimed at minimizing energy consumption while driving. The method was developed for the needs of an electric powered racing vehicle built for the purposes of the Shell Eco-marathon (SEM, the most famous and largest race of energy efficient vehicles. Model-based optimization was used to determine the driving strategy. The numerical model was elaborated in Simulink environment, which includes both the electric vehicle model and the environment, i.e., the race track as well as the vehicle environment and the atmospheric conditions. The vehicle model itself includes vehicle dynamic model, numerical model describing issues concerning resistance of rolling tire, resistance of the propulsion system, aerodynamic phenomena, model of the electric motor, and control system. For the purpose of identifying design and functional features of individual subassemblies and components, numerical and stand tests were carried out. The model itself was tested on the research tracks to tune the model and determine the calculation parameters. The evolutionary algorithms, which are available in the MATLAB Global Optimization Toolbox, were used for optimization. In the race conditions, the model was verified during SEM races in Rotterdam where the race vehicle scored the result consistent with the results of simulation calculations. In the following years, the experience gathered by the team gave us the vice Championship in the SEM 2016 in London.

  10. Population Modeling Approach to Optimize Crop Harvest Strategy. The Case of Field Tomato.

    Science.gov (United States)

    Tran, Dinh T; Hertog, Maarten L A T M; Tran, Thi L H; Quyen, Nguyen T; Van de Poel, Bram; Mata, Clara I; Nicolaï, Bart M

    2017-01-01

    In this study, the aim is to develop a population model based approach to optimize fruit harvesting strategies with regard to fruit quality and its derived economic value. This approach was applied to the case of tomato fruit harvesting under Vietnamese conditions. Fruit growth and development of tomato (cv. "Savior") was monitored in terms of fruit size and color during both the Vietnamese winter and summer growing seasons. A kinetic tomato fruit growth model was applied to quantify biological fruit-to-fruit variation in terms of their physiological maturation. This model was successfully calibrated. Finally, the model was extended to translate the fruit-to-fruit variation at harvest into the economic value of the harvested crop. It can be concluded that a model based approach to the optimization of harvest date and harvest frequency with regard to economic value of the crop as such is feasible. This approach allows growers to optimize their harvesting strategy by harvesting the crop at more uniform maturity stages meeting the stringent retail demands for homogeneous high quality product. The total farm profit would still depend on the impact a change in harvesting strategy might have on related expenditures. This model based harvest optimisation approach can be easily transferred to other fruit and vegetable crops improving homogeneity of the postharvest product streams.

  11. Strategies for memory-based decision making: Modeling behavioral and neural signatures within a cognitive architecture.

    Science.gov (United States)

    Fechner, Hanna B; Pachur, Thorsten; Schooler, Lael J; Mehlhorn, Katja; Battal, Ceren; Volz, Kirsten G; Borst, Jelmer P

    2016-12-01

    How do people use memories to make inferences about real-world objects? We tested three strategies based on predicted patterns of response times and blood-oxygen-level-dependent (BOLD) responses: one strategy that relies solely on recognition memory, a second that retrieves additional knowledge, and a third, lexicographic (i.e., sequential) strategy, that considers knowledge conditionally on the evidence obtained from recognition memory. We implemented the strategies as computational models within the Adaptive Control of Thought-Rational (ACT-R) cognitive architecture, which allowed us to derive behavioral and neural predictions that we then compared to the results of a functional magnetic resonance imaging (fMRI) study in which participants inferred which of two cities is larger. Overall, versions of the lexicographic strategy, according to which knowledge about many but not all alternatives is searched, provided the best account of the joint patterns of response times and BOLD responses. These results provide insights into the interplay between recognition and additional knowledge in memory, hinting at an adaptive use of these two sources of information in decision making. The results highlight the usefulness of implementing models of decision making within a cognitive architecture to derive predictions on the behavioral and neural level. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Modelling the transport system in China and evaluating the current strategies towards the sustainable transport development

    International Nuclear Information System (INIS)

    Liu, Wen; Lund, Henrik; Mathiesen, Brian Vad

    2013-01-01

    Transport is one of the most challenge sectors when addressing energy security and climate change due to its high reliance on oil products and lack of the alternative fuels. This paper explores the ability of three transport strategies to contribute to the development of a sustainable transport in China. With this purpose in mind, a Chinese transport model has been created and three current transport strategies which are high speed railway (HSR), urban rail transit (URT) and electric vehicle (EV) were evaluated together with a reference transport system in 2020. As conservative results, 13% of the energy saving and 12% of the CO 2 emission reduction can be attained by accomplishing three strategies compared with the reference transport system. However, the energy demand of transport in 2020 with the implementation of three strategies will be about 1.7 times as much as today. The three strategies show the potential of drawing the transport demand to the more energy efficient vehicles; however, more initiatives are needed if the sustainable transport is the long term objective, such as the solutions to stabilise the private vehicle demands, to continuously improve the vehicle efficiency and to boost the alternative fuels produced from the renewable energy sources. - Highlights: • A Chinese transport model was created and three transport strategies were evaluated • Transport is the biggest driver of the oil demand in China not the industry • The energy demand of transport in 2020 will be twice as much as today • Strategies contribute 13% energy saving and 12% CO 2 emission reduction • More initiatives are needed if a sustainable transport is the long-term objective

  13. A continuous latitudinal energy balance model to explore non-uniform climate engineering strategies

    Science.gov (United States)

    Bonetti, F.; McInnes, C. R.

    2016-12-01

    Current concentrations of atmospheric CO2 exceed measured historical levels in modern times, largely attributed to anthropogenic forcing since the industrial revolution. The required decline in emissions rates has never been achieved leading to recent interest in climate engineering for future risk-mitigation strategies. Climate engineering aims to offset human-driven climate change. It involves techniques developed both to reduce the concentration of CO2 in the atmosphere (Carbon Dioxide Removal (CDR) methods) and to counteract the radiative forcing that it generates (Solar Radiation Management (SRM) methods). In order to investigate effects of SRM technologies for climate engineering, an analytical model describing the main dynamics of the Earth's climate has been developed. The model is a time-dependent Energy Balance Model (EBM) with latitudinal resolution and allows for the evaluation of non-uniform climate engineering strategies. A significant disadvantage of climate engineering techniques involving the management of solar radiation is regional disparities in cooling. This model offers an analytical approach to design multi-objective strategies that counteract climate change on a regional basis: for example, to cool the Artic and restrict undesired impacts at mid-latitudes, or to control the equator-to-pole temperature gradient. Using the Green's function approach the resulting partial differential equation allows for the computation of the surface temperature as a function of time and latitude when a 1% per year increase in the CO2 concentration is considered. After the validation of the model through comparisons with high fidelity numerical models, it will be used to explore strategies for the injection of the aerosol precursors in the stratosphere. In particular, the model involves detailed description of the optical properties of the particles, the wash-out dynamics and the estimation of the radiative cooling they can generate.

  14. Deployment of e-health services - a business model engineering strategy.

    Science.gov (United States)

    Kijl, Björn; Nieuwenhuis, Lambert J M; Huis in 't Veld, Rianne M H A; Hermens, Hermie J; Vollenbroek-Hutten, Miriam M R

    2010-01-01

    We designed a business model for deploying a myofeedback-based teletreatment service. An iterative and combined qualitative and quantitative action design approach was used for developing the business model and the related value network. Insights from surveys, desk research, expert interviews, workshops and quantitative modelling were combined to produce the first business model and then to refine it in three design cycles. The business model engineering strategy provided important insights which led to an improved, more viable and feasible business model and related value network design. Based on this experience, we conclude that the process of early stage business model engineering reduces risk and produces substantial savings in costs and resources related to service deployment.

  15. A critical review of principal traffic noise models: Strategies and implications

    Energy Technology Data Exchange (ETDEWEB)

    Garg, Naveen, E-mail: ngarg@mail.nplindia.ernet.in [Apex Level Standards and Industrial Metrology Division, CSIR-National Physical Laboratory, New Delhi 110012 (India); Department of Mechanical, Production and Industrial Engineering, Delhi Technological University, Delhi 110042 (India); Maji, Sagar [Department of Mechanical, Production and Industrial Engineering, Delhi Technological University, Delhi 110042 (India)

    2014-04-01

    The paper presents an exhaustive comparison of principal traffic noise models adopted in recent years in developed nations. The comparison is drawn on the basis of technical attributes including source modelling and sound propagation algorithms. Although the characterization of source in terms of rolling and propulsion noise in conjunction with advanced numerical methods for sound propagation has significantly reduced the uncertainty in traffic noise predictions, the approach followed is quite complex and requires specialized mathematical skills for predictions which is sometimes quite cumbersome for town planners. Also, it is sometimes difficult to follow the best approach when a variety of solutions have been proposed. This paper critically reviews all these aspects pertaining to the recent models developed and adapted in some countries and also discusses the strategies followed and implications of these models. - Highlights: • Principal traffic noise models developed are reviewed. • Sound propagation algorithms used in traffic noise models are compared. • Implications of models are discussed.

  16. Strategies for OPEC's pricing decisions. [Using model of world energy market

    Energy Technology Data Exchange (ETDEWEB)

    Gately, D; Kyle, J F; Fischer, D

    1977-11-01

    A model of the world energy market that incorporates price expectations and lagged adjustments of demand and supply is used to examine implications of various price-paths that could be selected by OPEC. After demonstrating the sensitivity of the results to changes in functional specifications and certain parameter values, the authors discuss a variety of rule-of-thumb pricing strategies under which OPEC sets prices in response to available market signals. A strategy that is relatively cautious about further major price increases serves OPEC relatively well in comparison with other stategies, but there exists a real possibility of major, abrupt price increases within the next ten years.

  17. Performance deterioration modeling and optimal preventive maintenance strategy under scheduled servicing subject to mission time

    Directory of Open Access Journals (Sweden)

    Li Dawei

    2014-08-01

    Full Text Available Servicing is applied periodically in practice with the aim of restoring the system state and prolonging the lifetime. It is generally seen as an imperfect maintenance action which has a chief influence on the maintenance strategy. In order to model the maintenance effect of servicing, this study analyzes the deterioration characteristics of system under scheduled servicing. And then the deterioration model is established from the failure mechanism by compound Poisson process. On the basis of the system damage value and failure mechanism, the failure rate refresh factor is proposed to describe the maintenance effect of servicing. A maintenance strategy is developed which combines the benefits of scheduled servicing and preventive maintenance. Then the optimization model is given to determine the optimal servicing period and preventive maintenance time, with an objective to minimize the system expected life-cycle cost per unit time and a constraint on system survival probability for the duration of mission time. Subject to mission time, it can control the ability of accomplishing the mission at any time so as to ensure the high dependability. An example of water pump rotor relating to scheduled servicing is introduced to illustrate the failure rate refresh factor and the proposed maintenance strategy. Compared with traditional methods, the numerical results show that the failure rate refresh factor can describe the maintenance effect of servicing more intuitively and objectively. It also demonstrates that this maintenance strategy can prolong the lifetime, reduce the total lifetime maintenance cost and guarantee the dependability of system.

  18. The Effect of Toulmin’s Model of Argumentation Within TWPS Strategy on Students’ Critical Thinking on Argumentative Essay

    Directory of Open Access Journals (Sweden)

    Eko Suhartoyo

    2015-12-01

    Key Words: critical thinking, Toulmin’s model of argumentation, argumentative essay, Think-Write-Pair-Share strategy Abstrak: Penelitian ini bertujuan untuk menyelidiki efektivitas model argumentasi Toulmin dalam strategi TWPS pada kemampuan berpikir kritis esai argumentative mahasiswa. Desain kuasi-eksperi-mental digunakan dengan pretest-posttest dan nonrandomized control group. Subjek dari penelitian ini adalah 38 mahasiswa semester IV di Jurusan Bahasa Inggris Universitas Negeri Malang. Kelompok eksperimen diteliti dengan menggunakan model argumentasi dalam strategi TWPS sedangkan kelom-pok kontrol diteliti tanpa strategi TWPS. Kemampuan berpikir kritis siswa diukur dengan menggunakan uji esai argumentatif. ANCOVA digunakan untuk menguji hipotesis. Temuan menunjukkan tidak ada perbedaan yang signifikan pada kemampuan berpikir kritis siswa. Namun, model argumentasi Toulmin dalam strategi TWPS terbukti meningkatkan berpikir kritis siswa seperti yang ditunjukkan oleh nilai rata-rata. Kata kunci: berpikir kritis, model argumentasi toulmin, esai argumentatif, Think-Pair-Share Write- strategy

  19. A traction control strategy with an efficiency model in a distributed driving electric vehicle.

    Science.gov (United States)

    Lin, Cheng; Cheng, Xingqun

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention.

  20. Applying an Experiential Learning Model to the Teaching of Gateway Strategy Board Games

    Directory of Open Access Journals (Sweden)

    Aiko Sato

    2016-01-01

    Full Text Available The board game hobby has rapidly grown and evolved in recent years, but most of the non-digital games lack tips and tutorials and remain difficult to learn and teach effectively. In this project, we integrated a popular hobbyist approach to teaching modern strategy games with classical experiential learning elements (i.e., demonstration, observation, reflection, discussion and repeated experiences. We tested our model by teaching two modern board games to Japanese high school and university students. Questionnaires, gameplay data, self-ratings and discussions showed improved understanding and enjoyment, more strategic play and more interest in modern board games over the course of the instructional sequence. The model's repetition (the participants played each game three times was rated the most useful in terms of learning the games. Overall, the integrated model was largely successful in teaching strategy board games to new players, and we offer several recommendations for teachers, designers and researchers of board games.

  1. A Traction Control Strategy with an Efficiency Model in a Distributed Driving Electric Vehicle

    Science.gov (United States)

    Lin, Cheng

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention. PMID:25197697

  2. A new model for the redundancy allocation problem with component mixing and mixed redundancy strategy

    International Nuclear Information System (INIS)

    Gholinezhad, Hadi; Zeinal Hamadani, Ali

    2017-01-01

    This paper develops a new model for redundancy allocation problem. In this paper, like many recent papers, the choice of the redundancy strategy is considered as a decision variable. But, in our model each subsystem can exploit both active and cold-standby strategies simultaneously. Moreover, the model allows for component mixing such that components of different types may be used in each subsystem. The problem, therefore, boils down to determining the types of components, redundancy levels, and number of active and cold-standby units of each type for each subsystem to maximize system reliability by considering such constraints as available budget, weight, and space. Since RAP belongs to the NP-hard class of optimization problems, a genetic algorithm (GA) is developed for solving the problem. Finally, the performance of the proposed algorithm is evaluated by applying it to a well-known test problem from the literature with relatively satisfactory results. - Highlights: • A new model for the redundancy allocation problem in series–parallel systems is proposed. • The redundancy strategy of each subsystem is considered as a decision variable and can be active, cold-standby or mixed. • Component mixing is allowed, in other words components of any subsystem can be non-identical. • A genetic algorithm is developed for solving the problem. • Computational experiments demonstrate that the new model leads to interesting results.

  3. Application of a New Dynamic Heating System Model Using a Range of Common Control Strategies

    Directory of Open Access Journals (Sweden)

    Joshua Fong

    2016-06-01

    Full Text Available This research investigates the overall heating energy consumptions using various control strategies, secondary heat emitters, and primary plant for a building. Previous research has successfully demonstrated that a dynamic distributed heat emitter model embedded within a simplified third-order lumped parameter building model is capable of achieving improved results when compared to other commercially available modelling tools. With the enhanced ability to capture transient effects of emitter thermal capacity, this research studies the influence of control strategies and primary plant configurations on the rate of energy consumption of a heating system. Four alternative control strategies are investigated: zone feedback; weather-compensated; a combination of both of these methods; and thermostatic control. The plant alternative configurations consist of conventional boilers, biomass boilers, and heat pumps supporting radiator heating and underfloor heating. The performance of the model is tested on a primary school building and can be applied to any residential or commercial building with a heating system. Results show that the new methods reported offer greater detail and rigor in the conduct of building energy modelling.

  4. Strategies to reduce the complexity of hydrologic data assimilation for high-dimensional models

    Science.gov (United States)

    Hernandez, F.; Liang, X.

    2017-12-01

    Probabilistic forecasts in the geosciences offer invaluable information by allowing to estimate the uncertainty of predicted conditions (including threats like floods and droughts). However, while forecast systems based on modern data assimilation algorithms are capable of producing multi-variate probability distributions of future conditions, the computational resources required to fully characterize the dependencies between the model's state variables render their applicability impractical for high-resolution cases. This occurs because of the quadratic space complexity of storing the covariance matrices that encode these dependencies and the cubic time complexity of performing inference operations with them. In this work we introduce two complementary strategies to reduce the size of the covariance matrices that are at the heart of Bayesian assimilation methods—like some variants of (ensemble) Kalman filters and of particle filters—and variational methods. The first strategy involves the optimized grouping of state variables by clustering individual cells of the model into "super-cells." A dynamic fuzzy clustering approach is used to take into account the states (e.g., soil moisture) and forcings (e.g., precipitation) of each cell at each time step. The second strategy consists in finding a compressed representation of the covariance matrix that still encodes the most relevant information but that can be more efficiently stored and processed. A learning and a belief-propagation inference algorithm are developed to take advantage of this modified low-rank representation. The two proposed strategies are incorporated into OPTIMISTS, a state-of-the-art hybrid Bayesian/variational data assimilation algorithm, and comparative streamflow forecasting tests are performed using two watersheds modeled with the Distributed Hydrology Soil Vegetation Model (DHSVM). Contrasts are made between the efficiency gains and forecast accuracy losses of each strategy used in

  5. Multicriteria two-stage model of assessment of museums' business strategies

    Directory of Open Access Journals (Sweden)

    Mimović Predrag

    2017-01-01

    Full Text Available This paper analyzes and evaluates the museum activities in the current social, economic and political context, in order to prove the need for the identification and evaluation of business strategy for the cultural sector in general. In addition, the paper also studies methodological issues related to the model of evaluation and assessment of the strategy in the case of The 'Kragujevački Oktobar' Memorial Park. By applying the SWOT analysis and Analytic network process (ANP as an expert method for the support to decision making, critical success factors have been identified and their evaluation performed, in order to create optimum conditions for formulating business strategies and sustainable development of the Memorial Park.

  6. Perturbed cooperative-state feedback strategy for model predictive networked control of interconnected systems.

    Science.gov (United States)

    Tran, Tri; Ha, Q P

    2018-01-01

    A perturbed cooperative-state feedback (PSF) strategy is presented for the control of interconnected systems in this paper. The subsystems of an interconnected system can exchange data via the communication network that has multiple connection topologies. The PSF strategy can resolve both issues, the sensor data losses and the communication network breaks, thanks to the two components of the control including a cooperative-state feedback and a perturbation variable, e.g., u i =K ij x j +w i . The PSF is implemented in a decentralized model predictive control scheme with a stability constraint and a non-monotonic storage function (ΔV(x(k))≥0), derived from the dissipative systems theory. Numerical simulation for the automatic generation control problem in power systems is studied to illustrate the effectiveness of the presented PSF strategy. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  7. Achieving profitable growth in E and P: New strategies, business model

    International Nuclear Information System (INIS)

    Cavoulacos, P.; Deffarges, E.

    1997-01-01

    Major changes in the oil and gas environment during the last decade and a half have necessitated significant course corrections in upstream business strategies. Exogenous factors such as privatization and the opening of new opportunity areas have caused significant shifts in company strategies to drive growth, while lingering low commodity prices have applied continuous pressure to reduce costs. Successful upstream players have changed their strategies--from frontier exploration to development/production new ventures and on to gas and power plays--and built the capabilities necessary to achieve profitable growth. Moreover, these companies have adopted a new business model, an organization paradigm based on process-driven networks of business units, accountability and pay-for-performance, empowered multidisciplinary teams, and best practice sharing

  8. Assessing Reading Strategy Training based on CALLA model in EFL and ESL Context

    Directory of Open Access Journals (Sweden)

    Alireza Karbalaei

    2011-04-01

    Full Text Available Reading strategies instruction is currently gaining much attention as an effective means of enhancing reading comprehension. In this research, we examined the effect of Underlining Strategy Intervention, based on the CALLA model in EFL and ESL contexts. A group of 189 college students were randomly selected from different universities in Iran and India. Based on a proficiency test, students were grouped into high, moderate, and low level. Then, the underlining strategy was taught during the treatment sessions. The results suggest that intervention or explicit instruction was effective in increasing the reading comprehension of both Iranian and Indian students although Indian ESL students were able to perform better in comparison to their Iranian EFL counterparts. There was no significant difference between proficiency level and students' performance in reading comprehension in EFL and ESL contexts. In addition, there was no significant difference between males and females in both contexts.

  9. Soil mapping and processes models to support climate change mitigation and adaptation strategies: a review

    Science.gov (United States)

    Muñoz-Rojas, Miriam; Pereira, Paulo; Brevik, Eric; Cerda, Artemi; Jordan, Antonio

    2017-04-01

    As agreed in Paris in December 2015, global average temperature is to be limited to "well below 2 °C above pre-industrial levels" and efforts will be made to "limit the temperature increase to 1.5 °C above pre-industrial levels. Thus, reducing greenhouse gas emissions (GHG) in all sectors becomes critical and appropriate sustainable land management practices need to be taken (Pereira et al., 2017). Mitigation strategies focus on reducing the rate and magnitude of climate change by reducing its causes. Complementary to mitigation, adaptation strategies aim to minimise impacts and maximize the benefits of new opportunities. The adoption of both practices will require developing system models to integrate and extrapolate anticipated climate changes such as global climate models (GCMs) and regional climate models (RCMs). Furthermore, integrating climate models driven by socio-economic scenarios in soil process models has allowed the investigation of potential changes and threats in soil characteristics and functions in future climate scenarios. One of the options with largest potential for climate change mitigation is sequestering carbon in soils. Therefore, the development of new methods and the use of existing tools for soil carbon monitoring and accounting have therefore become critical in a global change context. For example, soil C maps can help identify potential areas where management practices that promote C sequestration will be productive and guide the formulation of policies for climate change mitigation and adaptation strategies. Despite extensive efforts to compile soil information and map soil C, many uncertainties remain in the determination of soil C stocks, and the reliability of these estimates depends upon the quality and resolution of the spatial datasets used for its calculation. Thus, better estimates of soil C pools and dynamics are needed to advance understanding of the C balance and the potential of soils for climate change mitigation. Here

  10. Glioblastoma, a brief review of history, molecular genetics, animal models and novel therapeutic strategies.

    Science.gov (United States)

    Agnihotri, Sameer; Burrell, Kelly E; Wolf, Amparo; Jalali, Sharzhad; Hawkins, Cynthia; Rutka, James T; Zadeh, Gelareh

    2013-02-01

    Glioblastoma (GBM) is the most common and lethal primary brain tumor. Over the past few years tremendous genomic and proteomic characterization along with robust animal models of GBM have provided invaluable data that show that "GBM", although histologically indistinguishable from one another, are comprised of molecularly heterogenous diseases. In addition, robust pre-clinical models and a better understanding of the core pathways disrupted in GBM are providing a renewed optimism for novel strategies targeting these devastating tumors. Here, we summarize a brief history of the disease, our current molecular knowledge, lessons from animal models and emerging concepts of angiogenesis, invasion, and metabolism in GBM that may lend themselves to therapeutic targeting.

  11. MARKET ENTRY STRATEGIES TO EMERGING MARKETS: A CONCEPTUAL MODEL OF TURNKEY PROJECT DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Bistra Vassileva

    2016-11-01

    Full Text Available The main purpose of the paper is to analyse the international market entry strategies in the light of globalisation processes and to propose a conceptual model of turnkey projects as market entry mode. The specific research objectives are as follows: 1. to develop an integrated framework of the turnkey marketing process as a conceptual model; 2. to analyse BRICS countries as potential host countries for turnkey projects implementation; 3. to assess potential implications of proposed conceptual model for global market entry decisions.

  12. The Pull Model as the E-Commerce Strategy For Business-To-Consumer Sites

    OpenAIRE

    Guillermo Reyes González; Ralf Eder Lange

    2013-01-01

    One of the solutions to stabilize the bullwhip effect is to provide the supply chain with the adequate mechanisms to make the information flow upstream (to the supplier) and downstream (to the consumer). This has led the e-commerce companies to implement a distribution model known as the Pull Model. This paper provides a literature review of the main characteristics of the Pull model and a comparison with the E-Commerce strategies and benefitsJournal: Revista de Administración, Finanzas y Eco...

  13. Study on Model for Human Resources Development Strategy in the Nuclear Field

    International Nuclear Information System (INIS)

    Lee, Eui Jin

    2005-01-01

    Qualified manpower is an essential for the successful implementation of a national long-term nuclear development program as well as the associated R and D programs. Such manpower could only be developed systematically under a well-established national model and strategy, which addresses the demand for human resources, number of personnel and timing, and the education and training. To discuss a model for human resources development, it is suggested to consider the following: approach to the Human Resources Development (HRD) Model, HRD policy targets, estimation of the manpower requirement, organizational coordination frameworks for the HRD, promotion of HRD in the action plan

  14. Parts of the Whole: Strategies for the Spread of Quantitative Literacy: What Models Can Tell Us

    Directory of Open Access Journals (Sweden)

    Dorothy Wallace

    2014-07-01

    Full Text Available Two conceptual frameworks, one from graph theory and one from dynamical systems, have been offered as explanations for complex phenomena in biology and also as possible models for the spread of ideas. The two models are based on different assumptions and thus predict quite different outcomes for the fate of either biological species or ideas. We argue that, depending on the culture in which they exist, one can identify which model is more likely to reflect the survival of two competing ideas. Based on this argument we suggest how two strategies for embedding and normalizing quantitative literacy in a given institution are likely to succeed or fail.

  15. Emissions and Fuel Consumption Modeling for Evaluating Environmental Effectiveness of ITS Strategies

    Directory of Open Access Journals (Sweden)

    Yuan-yuan Song

    2013-01-01

    Full Text Available Road transportation is a major fuel consumer and greenhouse gas emitter. Recently, the intelligent transportation systems (ITSs technologies, which can improve traffic flow and safety, have been developed to reduce the fuel consumption and vehicle emissions. Emission and fuel consumption estimation models play a key role in the evaluation of ITS technologies. Based on the influence analysis of driving parameters on vehicle emissions, this paper establishes a set of mesoscopic vehicle emission and fuel consumption models using the real-world vehicle operation and emission data. The results demonstrate that these models are more appropriate to evaluate the environmental effectiveness of ITS strategies with enough estimation accuracy.

  16. Development strategy and process models for phased automation of design and digital manufacturing electronics

    Science.gov (United States)

    Korshunov, G. I.; Petrushevskaya, A. A.; Lipatnikov, V. A.; Smirnova, M. S.

    2018-03-01

    The strategy of quality of electronics insurance is represented as most important. To provide quality, the processes sequence is considered and modeled by Markov chain. The improvement is distinguished by simple database means of design for manufacturing for future step-by-step development. Phased automation of design and digital manufacturing electronics is supposed. The MatLab modelling results showed effectiveness increase. New tools and software should be more effective. The primary digital model is proposed to represent product in the processes sequence from several processes till the whole life circle.

  17. Strategic Marketing for Indonesian Plywood Industry: An Analyse by using Porter Five Forces Model and Generic Strategy Framework

    OpenAIRE

    Makkarennu; Nakayasu, A.; Osozawa, K.; Ichikawa, M.

    2014-01-01

    The target for a marketing strategy is to find a way of achieving a sustainable competitive advantage over the other competing products and firms in a market.Good strategy serves as a road map for effective action. Porter???s five forces model and three generic strategies were used to evaluate the structure and the strategy for positioning of plywood industry in South Sulawesi, Indonesia. Qualitative research was carried out by using in-depth interview method. Having expressed either agree...

  18. Comparison of lung protective ventilation strategies in a rabbit model of acute lung injury.

    Science.gov (United States)

    Rotta, A T; Gunnarsson, B; Fuhrman, B P; Hernan, L J; Steinhorn, D M

    2001-11-01

    To determine the impact of different protective and nonprotective mechanical ventilation strategies on the degree of pulmonary inflammation, oxidative damage, and hemodynamic stability in a saline lavage model of acute lung injury. A prospective, randomized, controlled, in vivo animal laboratory study. Animal research facility of a health sciences university. Forty-six New Zealand White rabbits. Mature rabbits were instrumented with a tracheostomy and vascular catheters. Lavage-injured rabbits were randomized to receive conventional ventilation with either a) low peak end-expiratory pressure (PEEP; tidal volume of 10 mL/kg, PEEP of 2 cm H2O); b) high PEEP (tidal volume of 10 mL/kg, PEEP of 10 cm H2O); c) low tidal volume with PEEP above Pflex (open lung strategy, tidal volume of 6 mL/kg, PEEP set 2 cm H2O > Pflex); or d) high-frequency oscillatory ventilation. Animals were ventilated for 4 hrs. Lung lavage fluid and tissue samples were obtained immediately after animals were killed. Lung lavage fluid was assayed for measurements of total protein, elastase activity, tumor necrosis factor-alpha, and malondialdehyde. Lung tissue homogenates were assayed for measurements of myeloperoxidase activity and malondialdehyde. The need for inotropic support was recorded. Animals that received a lung protective strategy (open lung or high-frequency oscillatory ventilation) exhibited more favorable oxygenation and lung mechanics compared with the low PEEP and high PEEP groups. Animals ventilated by a lung protective strategy also showed attenuation of inflammation (reduced tracheal fluid protein, tracheal fluid elastase, tracheal fluid tumor necrosis factor-alpha, and pulmonary leukostasis). Animals treated with high-frequency oscillatory ventilation had attenuated oxidative injury to the lung and greater hemodynamic stability compared with the other experimental groups. Both lung protective strategies were associated with improved oxygenation, attenuated inflammation, and

  19. A MAINTENANCE STRATEGY MODEL FOR STATIC EQUIPMENT USING INSPECTION METHODOLOGIES AND RISK MANAGEMENT

    Directory of Open Access Journals (Sweden)

    J.K. Visser

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: Mechanical equipment used on process plants can be categorised into two main types, namely static and rotating equipment. A brief survey at a number of chemical process plants indicated that a number of maintenance strategies exist and are used for rotating equipment. However, some of these strategies are not directly applicable to static equipment, although the risk-based inspection (RBI methodology has been developed for pressure vessels. A generalised risk-based maintenance strategy for all types of static equipment does not currently exist. This paper describes the development of an optimised model of inspection methodologies, maintenance strategies, and risk management principles that are generically applicable for static equipment. It enables maintenance managers and engineers to select an applicable maintenance strategy and inspection methodology, based on the operational and business risks posed by the individual pieces of equipment.

    AFRIKAANSE OPSOMMING: Meganiese toerusting wat op prosesaanlegte gebruik word kan in twee kategorieë verdeel word, naamlik statiese en roterende toerusting. 'n Bondige ondersoek by 'n aantal chemiese prosesaanlegte het aangedui dat 'n aantal strategieë vir instandhouding van roterende toerusting gebruik word, terwyl die risikogebaseerde inspeksiemetodologie wel vir drukvate gebruik word. 'n Algemene risikogebaseerde instandhoudingstrategie vir alle tipes statiese toerusting is egter nie tans beskikbaar nie. Hierdie artikel beskryf die ontwikkeling van 'n geoptimeerde model van inspeksiemetodologieë, instandhoudingstrategieë, en risikobestuursbeginsels wat algemeen gebruik kan word vir statiese toerusting. Dit stel die instandhouding-bestuurders en -ingenieurs in staat om 'n instandhoudingstrategie en inspeksie-metodologie te kies, gebaseer op die operasionele en besigheidsrisiko's van die individuele toerusting.

  20. Approach and development strategy for an agent-based model of economic confidence.

    Energy Technology Data Exchange (ETDEWEB)

    Sprigg, James A.; Pryor, Richard J.; Jorgensen, Craig Reed

    2004-08-01

    We are extending the existing features of Aspen, a powerful economic modeling tool, and introducing new features to simulate the role of confidence in economic activity. The new model is built from a collection of autonomous agents that represent households, firms, and other relevant entities like financial exchanges and governmental authorities. We simultaneously model several interrelated markets, including those for labor, products, stocks, and bonds. We also model economic tradeoffs, such as decisions of households and firms regarding spending, savings, and investment. In this paper, we review some of the basic principles and model components and describe our approach and development strategy for emulating consumer, investor, and business confidence. The model of confidence is explored within the context of economic disruptions, such as those resulting from disasters or terrorist events.

  1. Model of coping strategies, resilience, psychological well-being, and perceived health among military personnel

    Directory of Open Access Journals (Sweden)

    Kuan-Jung Chen

    2018-01-01

    Full Text Available Background: Military personnel are confronted with physiological and psychological changes caused by stress and exposure to trauma. Although resilience may be protective against psychopathology, very few studies have explored the relationships between the resilience and coping strategies. The study aims to assess how different coping strategies affect resilience, psychological well-being (PWB, and perceived health among military personnel.Subjects and Methods: This study was a cross-sectional survey. Nuclear, biological, and chemical (NBC soldiers and nurses in the military medical center were recruited in Taiwan in November 2015. The survey comprised the Brief COPE Scale, Ryff's PWB Scale, and the Resilience Scale for Adults, which examined the relationships among coping strategies, PWB, resilience, and perceived health. Path analysis was applied.Results: We recruited 200 participants (145 male and 177 single aged 24.6 ± 4.7 years (range, 18–46 years. Resilience (coefficient = 0.60, P < 0.001 and PWB (coefficient = 0.33, P < 0.001 were better when using more approach-oriented coping strategies and fewer avoidant coping strategies, whereas the opposite pattern was seen when using avoidant coping (coefficient = −0.31, P < 0.001 for resilience and coefficient = −.20, P < 0.1 for PWB. PWB significantly predicted perceived health (coefficient = 0.45, P < 0.001.Conclusions: Resilience is higher when positive approach-oriented coping strategies are used, which directly affects PWB, and in turn, predicts better-perceived health. Our conceptual model indicates that interventions designed to promote approach-oriented coping strategies may help military personnel develop improved resilience, PWB, and perceived health status.

  2. Expert intuitions: how to model the decision strategies of airport customs officers?

    Science.gov (United States)

    Pachur, Thorsten; Marinello, Gianmarco

    2013-09-01

    How does expertise impact the selection of decision strategies? We asked airport customs officers and a novice control group to decide which passengers (described on several cue dimensions) they would submit to a search. Additionally, participants estimated the validities of the different cues. Then we modeled the decisions using compensatory strategies, which integrate many cues, and a noncompensatory heuristic, which relies on one-reason decision making. The majority of the customs officers were best described by the noncompensatory heuristic, whereas the majority of the novices were best described by a compensatory strategy. We also found that the experts' subjective cue validity estimates showed a higher dispersion across the cues and that differences in cue dispersion partially mediated differences in strategy use between experts and novices. Our results suggest that experts often rely on one-reason decision making and that expert-novice differences in strategy selection may reflect a response to the internal representation of the environment. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Holistic versus monomeric strategies for hydrological modelling of human-modified hydrosystems

    Directory of Open Access Journals (Sweden)

    I. Nalbantis

    2011-03-01

    Full Text Available The modelling of human-modified basins that are inadequately measured constitutes a challenge for hydrological science. Often, models for such systems are detailed and hydraulics-based for only one part of the system while for other parts oversimplified models or rough assumptions are used. This is typically a bottom-up approach, which seeks to exploit knowledge of hydrological processes at the micro-scale at some components of the system. Also, it is a monomeric approach in two ways: first, essential interactions among system components may be poorly represented or even omitted; second, differences in the level of detail of process representation can lead to uncontrolled errors. Additionally, the calibration procedure merely accounts for the reproduction of the observed responses using typical fitting criteria. The paper aims to raise some critical issues, regarding the entire modelling approach for such hydrosystems. For this, two alternative modelling strategies are examined that reflect two modelling approaches or philosophies: a dominant bottom-up approach, which is also monomeric and, very often, based on output information, and a top-down and holistic approach based on generalized information. Critical options are examined, which codify the differences between the two strategies: the representation of surface, groundwater and water management processes, the schematization and parameterization concepts and the parameter estimation methodology. The first strategy is based on stand-alone models for surface and groundwater processes and for water management, which are employed sequentially. For each model, a different (detailed or coarse parameterization is used, which is dictated by the hydrosystem schematization. The second strategy involves model integration for all processes, parsimonious parameterization and hybrid manual-automatic parameter optimization based on multiple objectives. A test case is examined in a hydrosystem in Greece

  4. Modeling nutrient sources, transport and management strategies in a coastal watershed, Southeast China.

    Science.gov (United States)

    Zhou, Pei; Huang, Jinliang; Hong, Huasheng

    2018-01-01

    Integrated watershed management requires an analytical model capable of revealing the full range of impacts that would be caused by the uses and developments in the watershed. The SPAtially Referenced Regressions On Watershed Attributes (SPARROW) model was developed in this study to provide empirical estimates of the sources, transport of total nitrogen (TN) and total phosphorus (TP) and to develop nutrient management strategies in the Jiulong River Watershed, southeast China that has enormous influence on the region's ecological safety. We calibrated the model using data related to daily streamflow, monthly TN and TP concentrations in 2014 at 30 locations. The model produced R 2 values for TN with 0.95 and TP with 0.94. It was found that for the entire watershed, TN came from fertilizer application (43%), livestock breeding (39%) and sewage discharge (18%), while TP came from livestock breeding (46%), fertilizer application (46%), and industrial discharge (8%). Fifty-eight percent of the TN and 80% of the TP in upstream reaches are delivered to the outlets of North and West rivers. A scenario analysis with SPARROW was coupled to develop suitable management strategies. Results revealed that controlling nutrient sources was effective in improving water quality. Normally sharp reduction in nutrient sources is not operational feasible. Hence, it is recommended that preventing nutrient on land from entering into the river as a suitable strategy in watershed management. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. THE INFLUENCE OF A MATHEMATICAL MODEL IN PRODUCTION STRATEGY: CONCEPTUAL DEVELOPMENT AND EMPIRICAL TEST

    Directory of Open Access Journals (Sweden)

    Paulo Cesar Chagas Rodrigues

    2012-07-01

    Full Text Available Acquire and produce what is strictly necessary are the goals of the organizations, since they aim companies more competitive and thereby reducing production costs. The research method is applied in nature, with a qualitative and quantitative approach, in which the objective of the research will be: exploratory and descriptive, with technical procedures, divided into: bibliographic, documentary, survey and concluding with a case study. On this assumption the main objective of this research is to develop and analyze a mathematical model that minimizes costs and maximizes the postponement of stocks in a company in the pulp, paper and paper products. Having been found only four papers, two articles and two theses that deal with the issue of demand management, supply chain and inventory postponement. These studies address the issue by modeling the productive time of the supply chain. For production segments this research may enable development of management practices demand and production strategy, allowing cost reductions and productivity gains possible. With the development of the mathematical model could ever analyze the behavior of demand and its influence on the productive strategy, strategy formulation regarding the purchase of raw materials and finished product storage in the last four years the company's results for the proposed model.

  6. The role of grazer predation strategies in the dynamics of consumer-resource based ecological models

    Science.gov (United States)

    Cropp, Roger; Moroz, Irene; Norbury, John

    2017-07-01

    We analyse a simple plankton system to provide a heuristic for more complex models such as Dynamic Green Ocean Models (DGOMs). Zooplankton foraging is either by generalist grazers that consume whatever they bump into or specialist grazers that actively seek particular prey. The zooplankton may further be classified as either facultative grazers that can survive on any of their prey or obligate grazers that depend on the presence of specific prey. A key result is that different prey dependencies can result in dramatically different impacts of grazing strategies on system outcomes. The grazing strategy can determine whether a system with obligate grazers will be stable, have regular, predictable cycles or be chaotic. Conversely, whether facultative zooplankton functioned as specialist or generalist grazers makes no qualitative difference to the dynamics of the system. These results demonstrate that the effect of different grazing strategies can be critically dependent on the grazer's dependency on specific prey. Great care must be taken when choosing functional forms for population interactions in DGOMs, particularly in scenarios such as climate change where parameters such as mortality and growth coefficients may change. A robust theoretical framework supporting model development and analysis is key to understanding how such choices can affect model properties and hence predictions.

  7. Modeling Approach/Strategy for Corrective Action Unit 97, Yucca Flat and Climax Mine , Revision 0

    Energy Technology Data Exchange (ETDEWEB)

    Janet Willie

    2003-08-01

    The objectives of the UGTA corrective action strategy are to predict the location of the contaminant boundary for each CAU, develop and implement a corrective action, and close each CAU. The process for achieving this strategy includes modeling to define the maximum extent of contaminant transport within a specified time frame. Modeling is a method of forecasting how the hydrogeologic system, including the underground test cavities, will behave over time with the goal of assessing the migration of radionuclides away from the cavities and chimneys. Use of flow and transport models to achieve the objectives of the corrective action strategy is specified in the FFACO. In the Yucca Flat/Climax Mine system, radionuclide migration will be governed by releases from the cavities and chimneys, and transport in alluvial aquifers, fractured and partially fractured volcanic rock aquifers and aquitards, the carbonate aquifers, and in intrusive units. Additional complexity is associated with multiple faults in Yucca Flat and the need to consider reactive transport mechanisms that both reduce and enhance the mobility of radionuclides. A summary of the data and information that form the technical basis for the model is provided in this document.

  8. Improving the Functional Diagnostic Process using Dynamic Master Logic Diagram (DMLD) Modeling Strategy

    International Nuclear Information System (INIS)

    Mohamed, A.H.

    2008-01-01

    In recent years, state based functional diagnostic systems have gained a growing attention among the model based diagnostic systems. They have been used to diagnose the new faults of the complex systems. On the other hand, a main point considered against it is its subjective, and the inability of reusing the knowledge gathered from one engineer by others. Different methods have been' suggested to solve these problems. In the same way, the suggested functional diagnostic system introduces the uses of Dynamic Master Logic Diagram (DMLD) modeling strategy for the functional diagnostic systems. DMLD has proven its power as a good modeling strategy. It can model the functions of the system's components in terms of a set of defined primitives for the domain of applications. However, the suggested system can use the DMLD technique to model the small functions of the system according to the defined primitives of its domain. So, the modeling process of the system is relatively invariant from one modeler to another. Also, the functions defined can be reused by other users in the domain for solving different problems. Besides, it can deal with the complex system in a flexible manner. Thus, the proposed system can improve the performance of the state based functional diagnostic systems. It can be applied for a wide area of the complex systems. It has been applied for a fluid system as a case of the real-time systems. The suggested system has proved its success as a powerful practical state based functional diagnostic system

  9. Generalized outcome-based strategy classification: comparing deterministic and probabilistic choice models.

    Science.gov (United States)

    Hilbig, Benjamin E; Moshagen, Morten

    2014-12-01

    Model comparisons are a vital tool for disentangling which of several strategies a decision maker may have used--that is, which cognitive processes may have governed observable choice behavior. However, previous methodological approaches have been limited to models (i.e., decision strategies) with deterministic choice rules. As such, psychologically plausible choice models--such as evidence-accumulation and connectionist models--that entail probabilistic choice predictions could not be considered appropriately. To overcome this limitation, we propose a generalization of Bröder and Schiffer's (Journal of Behavioral Decision Making, 19, 361-380, 2003) choice-based classification method, relying on (1) parametric order constraints in the multinomial processing tree framework to implement probabilistic models and (2) minimum description length for model comparison. The advantages of the generalized approach are demonstrated through recovery simulations and an experiment. In explaining previous methods and our generalization, we maintain a nontechnical focus--so as to provide a practical guide for comparing both deterministic and probabilistic choice models.

  10. Traffic Multiresolution Modeling and Consistency Analysis of Urban Expressway Based on Asynchronous Integration Strategy

    Directory of Open Access Journals (Sweden)

    Liyan Zhang

    2017-01-01

    Full Text Available The paper studies multiresolution traffic flow simulation model of urban expressway. Firstly, compared with two-level hybrid model, three-level multiresolution hybrid model has been chosen. Then, multiresolution simulation framework and integration strategies are introduced. Thirdly, the paper proposes an urban expressway multiresolution traffic simulation model by asynchronous integration strategy based on Set Theory, which includes three submodels: macromodel, mesomodel, and micromodel. After that, the applicable conditions and derivation process of the three submodels are discussed in detail. In addition, in order to simulate and evaluate the multiresolution model, “simple simulation scenario” of North-South Elevated Expressway in Shanghai has been established. The simulation results showed the following. (1 Volume-density relationships of three submodels are unanimous with detector data. (2 When traffic density is high, macromodel has a high precision and smaller error and the dispersion of results is smaller. Compared with macromodel, simulation accuracies of micromodel and mesomodel are lower but errors are bigger. (3 Multiresolution model can simulate characteristics of traffic flow, capture traffic wave, and keep the consistency of traffic state transition. Finally, the results showed that the novel multiresolution model can have higher simulation accuracy and it is feasible and effective in the real traffic simulation scenario.

  11. Strategy of competition between two groups based on an inflexible contrarian opinion model.

    Science.gov (United States)

    Li, Qian; Braunstein, Lidia A; Havlin, Shlomo; Stanley, H Eugene

    2011-12-01

    We introduce an inflexible contrarian opinion (ICO) model in which a fraction p of inflexible contrarians within a group holds a strong opinion opposite to the opinion held by the rest of the group. At the initial stage, stable clusters of two opinions, A and B, exist. Then we introduce inflexible contrarians which hold a strong B opinion into the opinion A group. Through their interactions, the inflexible contrarians are able to decrease the size of the largest A opinion cluster and even destroy it. We see this kind of method in operation, e.g., when companies send free new products to potential customers in order to convince them to adopt their products and influence others to buy them. We study the ICO model, using two different strategies, on both Erdös-Rényi and scale-free networks. In strategy I, the inflexible contrarians are positioned at random. In strategy II, the inflexible contrarians are chosen to be the highest-degree nodes. We find that for both strategies the size of the largest A cluster decreases to 0 as p increases as in a phase transition. At a critical threshold value, p(c), the system undergoes a second-order phase transition that belongs to the same universality class of mean-field percolation. We find that even for an Erdös-Rényi type model, where the degrees of the nodes are not so distinct, strategy II is significantly more effective in reducing the size of the largest A opinion cluster and, at very small values of p, the largest A opinion cluster is destroyed.

  12. Uncertainty and sensitivity analysis of control strategies using the benchmark simulation model No1 (BSM1).

    Science.gov (United States)

    Flores-Alsina, Xavier; Rodriguez-Roda, Ignasi; Sin, Gürkan; Gernaey, Krist V

    2009-01-01

    The objective of this paper is to perform an uncertainty and sensitivity analysis of the predictions of the Benchmark Simulation Model (BSM) No. 1, when comparing four activated sludge control strategies. The Monte Carlo simulation technique is used to evaluate the uncertainty in the BSM1 predictions, considering the ASM1 bio-kinetic parameters and influent fractions as input uncertainties while the Effluent Quality Index (EQI) and the Operating Cost Index (OCI) are focused on as model outputs. The resulting Monte Carlo simulations are presented using descriptive statistics indicating the degree of uncertainty in the predicted EQI and OCI. Next, the Standard Regression Coefficients (SRC) method is used for sensitivity analysis to identify which input parameters influence the uncertainty in the EQI predictions the most. The results show that control strategies including an ammonium (S(NH)) controller reduce uncertainty in both overall pollution removal and effluent total Kjeldahl nitrogen. Also, control strategies with an external carbon source reduce the effluent nitrate (S(NO)) uncertainty increasing both their economical cost and variability as a trade-off. Finally, the maximum specific autotrophic growth rate (micro(A)) causes most of the variance in the effluent for all the evaluated control strategies. The influence of denitrification related parameters, e.g. eta(g) (anoxic growth rate correction factor) and eta(h) (anoxic hydrolysis rate correction factor), becomes less important when a S(NO) controller manipulating an external carbon source addition is implemented.

  13. An Integrated Hydro-Economic Modelling Framework to Evaluate Water Allocation Strategies I: Model Development.

    NARCIS (Netherlands)

    George, B.; Malano, H.; Davidson, B.; Hellegers, P.; Bharati, L.; Sylvain, M.

    2011-01-01

    In this paper an integrated modelling framework for water resources planning and management that can be used to carry out an analysis of alternative policy scenarios for water allocation and use is described. The modelling approach is based on integrating a network allocation model (REALM) and a

  14. A stochastic SIRS epidemic model with infectious force under intervention strategies

    Science.gov (United States)

    Cai, Yongli; Kang, Yun; Banerjee, Malay; Wang, Weiming

    2015-12-01

    In this paper, we extend a classical SIRS epidemic model with the infectious forces under intervention strategies from a deterministic framework to a stochastic differential equation (SDE) one through introducing random fluctuations. The value of our study lies in two aspects. Mathematically, by using the Markov semigroups theory, we prove that the reproduction number R0S can be used to govern the stochastic dynamics of SDE model. If R0S 1, under mild extra conditions, it has an endemic stationary distribution which leads to the stochastical persistence of the disease. Epidemiologically, we find that random fluctuations can suppress disease outbreak, which can provide us some useful control strategies to regulate disease dynamics.

  15. Cognitive Work Analysis: Preliminary Data for a Model of Problem Solving Strategies

    Science.gov (United States)

    Rothmayer, Mark; Blue, Jennifer

    2007-10-01

    Investigations into problem solving strategies are part of the field of physics education research where investigators seek to improve physics instruction by conducting basic research of problem solving abilities among students, differences in knowledge representations between experts and novices, and how to transfer knowledge structures more effectively onto novices. We developed a new conceptual research tool in our laboratory, where we could potentially map the step by step flow of problem solving strategies among experts and novices. This model is derived from the theory of Cognitive Work Analysis, which is grounded in ecological psychology, and as far as we know it has never been applied to a knowledge domain like physics. We collected survey data from 140 undergraduates enrolled in an algebra based introductory physics course at Miami University as part of a larger study aimed to test the validity of the model. Preliminary data will be presented and discussed.

  16. [Real-time detection of quality of Chinese materia medica: strategy of NIR model evaluation].

    Science.gov (United States)

    Wu, Zhi-sheng; Shi, Xin-yuan; Xu, Bing; Dai, Xing-xing; Qiao, Yan-jiang

    2015-07-01

    The definition of critical quality attributes of Chinese materia medica ( CMM) was put forward based on the top-level design concept. Nowadays, coupled with the development of rapid analytical science, rapid assessment of critical quality attributes of CMM was firstly carried out, which was the secondary discipline branch of CMM. Taking near infrared (NIR) spectroscopy as an example, which is a rapid analytical technology in pharmaceutical process over the past decade, systematic review is the chemometric parameters in NIR model evaluation. According to the characteristics of complexity of CMM and trace components analysis, a multi-source information fusion strategy of NIR model was developed for assessment of critical quality attributes of CMM. The strategy has provided guideline for NIR reliable analysis in critical quality attributes of CMM.

  17. A Dynamic Simulation Model of Organizational Culture and Business Strategy Effects on Performance

    Science.gov (United States)

    Trivellas, Panagiotis; Reklitis, Panagiotis; Konstantopoulos, Nikolaos

    2007-12-01

    In the past two decades, organizational culture literature has gained tremendous interest for both academic and practitioners. This is based not only on the suggestion that culture is related to performance, but also on the view that it is subject of direct managerial control and manipulation to the desired direction. In the present paper, we adopt Competing Values Framework (CVF) to operationalise organizational culture and Porter's typology to conceptualize business strategy (cost leadership, innovative and marketing differentiation, and focus). Although simulation of social events is a quite difficult task, since there are so many considerations (not all well understood) involved, in the present study we developed a dynamic model to simulate the organizational culture and strategy effects on financial performance. Data obtained from a six-year survey in the banking sector of a European developing economy was used for the proposed dynamic model development.

  18. Use of the Edmonds-Reilly Model to model energy-sector impacts of greenhouse gas emissions control strategies

    International Nuclear Information System (INIS)

    Barns, D.W.; Edmonds, J.A.; Reilly, J.M.

    1992-01-01

    The purpose of this paper is to document the results of our application of the Edmonds-Reilly Model (ERM) using several scenarios provided in connection with the 1991 Energy Modeling Forum (EMF). The purpose of this session of the forum is to compare the efforts of several modeling teams using common assumptions to examine the energy sector impacts of strategies to control greenhouse gas emissions. Because the output of this exercise is data-rich, most of this exposition is in graphical form with the narrative serving mainly as a roadmap for moving from one highlight to the next. The following sessions briefly describe the model and some of the special modifications made for this effort. The case-by-case discussion is contained in Section IV, followed by a summary of the potential pitfalls involved in attempting to assess the cost of emissions reduction from the model data

  19. A Model of Yeast Cell-Cycle Regulation Based on a Standard Component Modeling Strategy for Protein Regulatory Networks.

    Directory of Open Access Journals (Sweden)

    Teeraphan Laomettachit

    Full Text Available To understand the molecular mechanisms that regulate cell cycle progression in eukaryotes, a variety of mathematical modeling approaches have been employed, ranging from Boolean networks and differential equations to stochastic simulations. Each approach has its own characteristic strengths and weaknesses. In this paper, we propose a "standard component" modeling strategy that combines advantageous features of Boolean networks, differential equations and stochastic simulations in a framework that acknowledges the typical sorts of reactions found in protein regulatory networks. Applying this strategy to a comprehensive mechanism of the budding yeast cell cycle, we illustrate the potential value of standard component modeling. The deterministic version of our model reproduces the phenotypic properties of wild-type cells and of 125 mutant strains. The stochastic version of our model reproduces the cell-to-cell variability of wild-type cells and the partial viability of the CLB2-dbΔ clb5Δ mutant strain. Our simulations show that mathematical modeling with "standard components" can capture in quantitative detail many essential properties of cell cycle control in budding yeast.

  20. Dynamic electro-thermal modeling of all-vanadium redox flow battery with forced cooling strategies

    International Nuclear Information System (INIS)

    Wei, Zhongbao; Zhao, Jiyun; Xiong, Binyu

    2014-01-01

    Highlights: • A dynamic electro-thermal model is proposed for VRB with forced cooling. • The Foster network is adopted to model the battery cooling process. • Both the electrolyte temperature and terminal voltage can be accurately predicted. • The flow rate of electrolyte and coolant significantly impact battery performance. - Abstract: The present study focuses on the dynamic electro-thermal modeling for the all-vanadium redox flow battery (VRB) with forced cooling strategies. The Foster network is adopted to dynamically model the heat dissipation of VRB with heat exchangers. The parameters of Foster network are extracted by fitting the step response of it to the results of linearized CFD model. Then a complete electro-thermal model is proposed by coupling the heat generation model, Foster network and electrical model. Results show that the established model has nearly the same accuracy with the nonlinear CFD model in electrolyte temperature prediction but drastically improves the computational efficiency. The modeled terminal voltage is also benchmarked with the experimental data under different current densities. The electrolyte temperature is found to be significantly influenced by the flow rate of coolant. As compared, although the electrolyte flow rate has unremarkable impact on electrolyte temperature, its effect on system pressure drop and battery efficiency is significant. Increasing the electrolyte flow rate improves the coulombic efficiency, voltage efficiency and energy efficiency simultaneously but at the expense of higher pump power demanded. An optimal flow rate exists for each operating condition to maximize the system efficiency

  1. Strategies for the coupling of global and local crystal growth models

    Science.gov (United States)

    Derby, Jeffrey J.; Lun, Lisa; Yeckel, Andrew

    2007-05-01

    The modular coupling of existing numerical codes to model crystal growth processes will provide for maximum effectiveness, capability, and flexibility. However, significant challenges are posed to make these coupled models mathematically self-consistent and algorithmically robust. This paper presents sample results from a coupling of the CrysVUn code, used here to compute furnace-scale heat transfer, and Cats2D, used to calculate melt fluid dynamics and phase-change phenomena, to form a global model for a Bridgman crystal growth system. However, the strategy used to implement the CrysVUn-Cats2D coupling is unreliable and inefficient. The implementation of under-relaxation within a block Gauss-Seidel iteration is shown to be ineffective for improving the coupling performance in a model one-dimensional problem representative of a melt crystal growth model. Ideas to overcome current convergence limitations using approximations to a full Newton iteration method are discussed.

  2. Evaluating stormwater micropollutant control strategies by the application of an integrated model

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Sharma, Anitha Kumari; Ledin, Anna

    2011-01-01

    and enhancement of existing treatment) for reducing heavy metals (copper, zinc) and organic MP (fluoranthene). The runoff quality model showed high uncertainty, with prediction bounds strongly affected by the exceptionally high measured concentrations. The model quantified the greater benefits of the source......The estimation of micropollutant (MP) fluxes in stormwater systems is a fundamental task to enable the elaboration of strategies to reduce stormwater MP discharge to natural waters. Dynamic models can represent important tools which can integrate the limited data provided by monitoring campaigns....... This study presents an application of an integrated dynamic model to estimate MP fluxes in stormwater systems in combination with stormwater quality measurements. MP sources were identified by using GIS land usage data. Runoff quality was simulated by using a conceptual accumulation/washoff model...

  3. Strategies for Enhancing Nonlinear Internal Model Control of pH Processes

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Qiuping.; Rangaiah, G.P. [The National University of Singapore, Singapore (Singapore). Dept. of Chemical and Environmental Engineering

    1999-02-01

    Control of neutralization processes is very difficult due to nonlinear dynamics, different types of disturbances and modeling errors. The objective of the paper is to evaluate two strategies (augmented internal model control, AuIMC and adaptive internal model control, AdIMC) for enhancing pH control by nonlinear internal model control (NIMC). A NIMC controller is derived directly form input output linearization. The AuIMC is composed of NIMC and an additional loop through which the difference between the process and model outputs is fed back and added to the input of the controller. For the AdIMC, and adaptive law with two tuning parameters is proposed for estimating the unknown parameter. Both AuIMC and AdIMC are extensively tested via simulation for pH neutralization. The theoretical and simulation results show that both the proposed strategies can reduce the effect of modeling errors and disturbances, and thereby enhance the performance of NIMC for pH processes. (author)

  4. Deployment and implementation of the Grundfos' sustainability strategy by means of the ecodesign maturity model

    DEFF Research Database (Denmark)

    Pigosso, Daniela Cristina Antelmi; McAloone, Tim C.; Rozenfeld, Henrique

    2014-01-01

    Companies are increasingly realizing the needs and opportunities for implementing sustainability into their business processes and corporate culture. This paper describes the approach followed by Grundfos to deploy its Sustainability Strategy for the development of Sustainable Product Solutions......, by means of the Ecodesign Maturity Model (EcoM2), which included the diagnosis of their current maturity profile, the definition of a strategic roadmap for ecodesign implementation and the implementation of the defined projects....

  5. STRATEGI VALUATION MODEL: PENGAMBILAN KEPUTUSAN INVESTASI PADA PERUSAHAAN MANUFAKTUR DI BURSA EFEK INDONESIA

    OpenAIRE

    Hasa Nurrohim KP; Sri Dwi Ari Ambarwati

    2017-01-01

    This research was based upon Riahi-Belkaoui & Picur (2001) and Richard G Baker(1999) result which supposed there was relation between IOS with dividend and retained earningpolicy. Purpose of this research was to know empirically impact of valuation model strategy toinvestment decision making on manufacturing company. Using data of manufacturing companieswas listed during 2000-2005 in Indonesia Stock Exchange and analyzed with multiple regression.The results found were: 1). There was no ef...

  6. A Decision-Making Model of Social Shopping in Franchising: Assessing Collaboration Strategies

    OpenAIRE

    In Lee; Choong-Kwon Lee; Sangjin Yoo; Moo-Jin Choi

    2015-01-01

    Our paper develops a decision-making model of social shopping in franchising to understand impacts of various collaboration strategies on profits of a social intermediary, a franchisor, and a franchisee. Three decision variables are considered to make a daily deal promotion in a manner that results in optimal profits: the social intermediary's advertising expense, the franchisee's service quality expense, and the franchisor's financial assistance to the franchisee. The analysis shows that whi...

  7. On a perturbed Sparre Andersen risk model with multi-layer dividend strategy

    Science.gov (United States)

    Yang, Hu; Zhang, Zhimin

    2009-10-01

    In this paper, we consider a perturbed Sparre Andersen risk model, in which the inter-claim times are generalized Erlang(n) distributed. Under the multi-layer dividend strategy, piece-wise integro-differential equations for the discounted penalty functions are derived, and a recursive approach is applied to express the solutions. A numerical example to calculate the ruin probabilities is given to illustrate the solution procedure.

  8. Comparative effectiveness of different strategies of oral cholera vaccination in bangladesh: a modeling study.

    Directory of Open Access Journals (Sweden)

    Dobromir T Dimitrov

    2014-12-01

    Full Text Available Killed, oral cholera vaccines have proven safe and effective, and several large-scale mass cholera vaccination efforts have demonstrated the feasibility of widespread deployment. This study uses a mathematical model of cholera transmission in Bangladesh to examine the effectiveness of potential vaccination strategies.We developed an age-structured mathematical model of cholera transmission and calibrated it to reproduce the dynamics of cholera in Matlab, Bangladesh. We used the model to predict the effectiveness of different cholera vaccination strategies over a period of 20 years. We explored vaccination programs that targeted one of three increasingly focused age groups (the entire vaccine-eligible population of age one year and older, children of ages 1 to 14 years, or preschoolers of ages 1 to 4 years and that could occur either as campaigns recurring every five years or as continuous ongoing vaccination efforts. Our modeling results suggest that vaccinating 70% of the population would avert 90% of cholera cases in the first year but that campaign and continuous vaccination strategies differ in effectiveness over 20 years. Maintaining 70% coverage of the population would be sufficient to prevent sustained transmission of endemic cholera in Matlab, while vaccinating periodically every five years is less effective. Selectively vaccinating children 1-14 years old would prevent the most cholera cases per vaccine administered in both campaign and continuous strategies.We conclude that continuous mass vaccination would be more effective against endemic cholera than periodic campaigns. Vaccinating children averts more cases per dose than vaccinating all age groups, although vaccinating only children is unlikely to control endemic cholera in Bangladesh. Careful consideration must be made before generalizing these results to other regions.

  9. Comparative effectiveness of different strategies of oral cholera vaccination in bangladesh: a modeling study.

    Science.gov (United States)

    Dimitrov, Dobromir T; Troeger, Christopher; Halloran, M Elizabeth; Longini, Ira M; Chao, Dennis L

    2014-12-01

    Killed, oral cholera vaccines have proven safe and effective, and several large-scale mass cholera vaccination efforts have demonstrated the feasibility of widespread deployment. This study uses a mathematical model of cholera transmission in Bangladesh to examine the effectiveness of potential vaccination strategies. We developed an age-structured mathematical model of cholera transmission and calibrated it to reproduce the dynamics of cholera in Matlab, Bangladesh. We used the model to predict the effectiveness of different cholera vaccination strategies over a period of 20 years. We explored vaccination programs that targeted one of three increasingly focused age groups (the entire vaccine-eligible population of age one year and older, children of ages 1 to 14 years, or preschoolers of ages 1 to 4 years) and that could occur either as campaigns recurring every five years or as continuous ongoing vaccination efforts. Our modeling results suggest that vaccinating 70% of the population would avert 90% of cholera cases in the first year but that campaign and continuous vaccination strategies differ in effectiveness over 20 years. Maintaining 70% coverage of the population would be sufficient to prevent sustained transmission of endemic cholera in Matlab, while vaccinating periodically every five years is less effective. Selectively vaccinating children 1-14 years old would prevent the most cholera cases per vaccine administered in both campaign and continuous strategies. We conclude that continuous mass vaccination would be more effective against endemic cholera than periodic campaigns. Vaccinating children averts more cases per dose than vaccinating all age groups, although vaccinating only children is unlikely to control endemic cholera in Bangladesh. Careful consideration must be made before generalizing these results to other regions.

  10. Short-term airing by natural ventilation - modeling and control strategies.

    Science.gov (United States)

    Perino, M; Heiselberg, P

    2009-10-01

    The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. This kind of system frequently integrates traditional mechanical ventilation components with natural ventilation devices, such as motorized windows and louvers. Among the various ventilation strategies that are currently available, buoyancy driven single-sided natural ventilation has proved to be very effective and can provide high air change rates for temperature and IAQ control. However, in order to promote a wider applications of these systems, an improvement in the knowledge of their working principles and the availability of new design and simulation tools is necessary. In this context, the paper analyses and presents the results of a research that was aimed at developing and validating numerical models for the analysis of buoyancy driven single-sided natural ventilation systems. Once validated, these models can be used to optimize control strategies in order to achieve satisfactory indoor comfort conditions and IAQ. Practical Implications Numerical and experimental analyses have proved that short-term airing by intermittent ventilation is an effective measure to satisfactorily control IAQ. Different control strategies have been investigated to optimize the capabilities of the systems. The proposed zonal model has provided good performances and could be adopted as a design tool, while CFD simulations can be profitably used for detailed studies of the pollutant concentration distribution in a room and to address local discomfort problems.

  11. Evaluating Internal Model Strength and Performance of Myoelectric Prosthesis Control Strategies.

    Science.gov (United States)

    Shehata, Ahmed W; Scheme, Erik J; Sensinger, Jonathon W

    2018-05-01

    On-going developments in myoelectric prosthesis control have provided prosthesis users with an assortment of control strategies that vary in reliability and performance. Many studies have focused on improving performance by providing feedback to the user but have overlooked the effect of this feedback on internal model development, which is key to improve long-term performance. In this paper, the strength of internal models developed for two commonly used myoelectric control strategies: raw control with raw feedback (using a regression-based approach) and filtered control with filtered feedback (using a classifier-based approach), were evaluated using two psychometric measures: trial-by-trial adaptation and just-noticeable difference. The performance of both strategies was also evaluated using Schmidt's style target acquisition task. Results obtained from 24 able-bodied subjects showed that although filtered control with filtered feedback had better short-term performance in path efficiency ( ), raw control with raw feedback resulted in stronger internal model development ( ), which may lead to better long-term performance. Despite inherent noise in the control signals of the regression controller, these findings suggest that rich feedback associated with regression control may be used to improve human understanding of the myoelectric control system.

  12. Modeling change in learning strategies throughout higher education: a multi-indicator latent growth perspective.

    Science.gov (United States)

    Coertjens, Liesje; Donche, Vincent; De Maeyer, Sven; Vanthournout, Gert; Van Petegem, Peter

    2013-01-01

    The change in learning strategies during higher education is an important topic of research in the Student Approaches to Learning field. Although the studies on this topic are increasingly longitudinal, analyses have continued to rely primarily on traditional statistical methods. The present research is innovative in the way it uses a multi-indicator latent growth analysis in order to more accurately estimate the general and differential development in learning strategy scales. Moreover, the predictive strength of the latent growth models are estimated. The sample consists of one cohort of Flemish University College students, 245 of whom participated in the three measurement waves by filling out the processing and regulation strategies scales of the Inventory of Learning Styles--Short Versions. Independent-samples t-tests revealed that the longitudinal group is a non-random subset of students starting University College. For each scale, a multi-indicator latent growth model is estimated using Mplus 6.1. Results suggest that, on average, during higher education, students persisting in their studies in a non-delayed manner seem to shift towards high-quality learning and away from undirected and surface-oriented learning. Moreover, students from the longitudinal group are found to vary in their initial levels, while, unexpectedly, not in their change over time. Although the growth models fit the data well, significant residual variances in the latent factors remain.

  13. Validation and implementation of model based control strategies at an industrial wastewater treatment plant.

    Science.gov (United States)

    Demey, D; Vanderhaegen, B; Vanhooren, H; Liessens, J; Van Eyck, L; Hopkins, L; Vanrolleghem, P A

    2001-01-01

    In this paper, the practical implementation and validation of advanced control strategies, designed using model based techniques, at an industrial wastewater treatment plant is demonstrated. The plant under study is treating the wastewater of a large pharmaceutical production facility. The process characteristics of the wastewater treatment were quantified by means of tracer tests, intensive measurement campaigns and the use of on-line sensors. In parallel, a dynamical model of the complete wastewater plant was developed according to the specific kinetic characteristics of the sludge and the highly varying composition of the industrial wastewater. Based on real-time data and dynamic models, control strategies for the equalisation system, the polymer dosing and phosphorus addition were established. The control strategies are being integrated in the existing SCADA system combining traditional PLC technology with robust PC based control calculations. The use of intelligent control in wastewater treatment offers a wide spectrum of possibilities to upgrade existing plants, to increase the capacity of the plant and to eliminate peaks. This can result in a more stable and secure overall performance and, finally, in cost savings. The use of on-line sensors has a potential not only for monitoring concentrations, but also for manipulating flows and concentrations. This way the performance of the plant can be secured.

  14. Modeling change in learning strategies throughout higher education: a multi-indicator latent growth perspective.

    Directory of Open Access Journals (Sweden)

    Liesje Coertjens

    Full Text Available The change in learning strategies during higher education is an important topic of research in the Student Approaches to Learning field. Although the studies on this topic are increasingly longitudinal, analyses have continued to rely primarily on traditional statistical methods. The present research is innovative in the way it uses a multi-indicator latent growth analysis in order to more accurately estimate the general and differential development in learning strategy scales. Moreover, the predictive strength of the latent growth models are estimated. The sample consists of one cohort of Flemish University College students, 245 of whom participated in the three measurement waves by filling out the processing and regulation strategies scales of the Inventory of Learning Styles--Short Versions. Independent-samples t-tests revealed that the longitudinal group is a non-random subset of students starting University College. For each scale, a multi-indicator latent growth model is estimated using Mplus 6.1. Results suggest that, on average, during higher education, students persisting in their studies in a non-delayed manner seem to shift towards high-quality learning and away from undirected and surface-oriented learning. Moreover, students from the longitudinal group are found to vary in their initial levels, while, unexpectedly, not in their change over time. Although the growth models fit the data well, significant residual variances in the latent factors remain.

  15. Argos: Residential end-use simulation model for load management strategy analysis

    International Nuclear Information System (INIS)

    Capasso, A.; Lamedica, R.; Prudenzi, A.

    1992-01-01

    In recent years, load management (LM) strategies, aimed at the optimization of available energy resources, as well as, the reduction of investments for new power plants, have been applied worldwide in residential end-use assessments. However, the forecasting of LM strategy impacts on the residential sector is very complex because it is based on a preliminary evaluation of the customers' proclivity to adapt their load characteristics to utility aims. In order to reduce load analysis requirements, which are substantial due to the need for thorough statistical analyses, complex field tests and measurements, the availability of models taking into account customer behavioural aspects is of paramount importance. This paper illustrates a simulation model which allows the performance of numerical evaluations concerning the effectiveness of some LM strategies applied to a residential end-use area load profile as previously determined by the aggregation of the contributions of individual households. This model enabled the evaluation of the impact, on the load profile, of a time-of-day tariff such as that recently introduced in Italy

  16. Estrogen receptor testing and 10-year mortality from breast cancer: A model for determining testing strategy

    Directory of Open Access Journals (Sweden)

    Christopher Naugler

    2012-01-01

    Full Text Available Background: The use of adjuvant tamoxifen therapy in the treatment of estrogen receptor (ER expressing breast carcinomas represents a major advance in personalized cancer treatment. Because there is no benefit (and indeed there is increased morbidity and mortality associated with the use of tamoxifen therapy in ER-negative breast cancer, its use is restricted to women with ER expressing cancers. However, correctly classifying cancers as ER positive or negative has been challenging given the high reported false negative test rates for ER expression in surgical specimens. In this paper I model practice recommendations using published information from clinical trials to address the question of whether there is a false negative test rate above which it is more efficacious to forgo ER testing and instead treat all patients with tamoxifen regardless of ER test results. Methods: I used data from randomized clinical trials to model two different hypothetical treatment strategies: (1 the current strategy of treating only ER positive women with tamoxifen and (2 an alternative strategy where all women are treated with tamoxifen regardless of ER test results. The variables used in the model are literature-derived survival rates of the different combinations of ER positivity and treatment with tamoxifen, varying true ER positivity rates and varying false negative ER testing rates. The outcome variable was hypothetical 10-year survival. Results: The model predicted that there will be a range of true ER rates and false negative test rates above which it would be more efficacious to treat all women with breast cancer with tamoxifen and forgo ER testing. This situation occurred with high true positive ER rates and false negative ER test rates in the range of 20-30%. Conclusions: It is hoped that this model will provide an example of the potential importance of diagnostic error on clinical outcomes and furthermore will give an example of how the effect of that

  17. An Integrated Qualitative and Quantitative Biochemical Model Learning Framework Using Evolutionary Strategy and Simulated Annealing.

    Science.gov (United States)

    Wu, Zujian; Pang, Wei; Coghill, George M

    2015-01-01

    Both qualitative and quantitative model learning frameworks for biochemical systems have been studied in computational systems biology. In this research, after introducing two forms of pre-defined component patterns to represent biochemical models, we propose an integrative qualitative and quantitative modelling framework for inferring biochemical systems. In the proposed framework, interactions between reactants in the candidate models for a target biochemical system are evolved and eventually identified by the application of a qualitative model learning approach with an evolution strategy. Kinetic rates of the models generated from qualitative model learning are then further optimised by employing a quantitative approach with simulated annealing. Experimental results indicate that our proposed integrative framework is feasible to learn the relationships between biochemical reactants qualitatively and to make the model replicate the behaviours of the target system by optimising the kinetic rates quantitatively. Moreover, potential reactants of a target biochemical system can be discovered by hypothesising complex reactants in the synthetic models. Based on the biochemical models learned from the proposed framework, biologists can further perform experimental study in wet laboratory. In this way, natural biochemical systems can be better understood.

  18. Evaluating environmental and economic consequences of alternative pest management strategies: results of modeling workshops

    Science.gov (United States)

    Johnson, Richard L.; Andrews, Austin K.; Auble, Gregor T.L.; Ellison, Richard A.; Hamilton, David B.; Roelle, James E.; McNamee, Peter J.

    1983-01-01

    The U.S. Environmental Protection Agency (EPA) needs a comprehensive method to evaluate the human health and environmental effects of alternative agricultural pest management strategies. This project explored the utility of Adaptive Environmental Assessment (AEA) techniques for meeting this need. The project objectives were to produce models for environmental impact analysis, improve communications, identify research needs and data requirements, and demonstrate a process for resolving conflicts. The project was structured around the construction (in an initial 2 1/2-day workshop) and examination (in a second 2 1/2-day workshop) of a simulation model of a corn agroecosystem.

  19. A novel model-based control strategy for aerobic filamentous fungal fed-batch fermentation processes

    DEFF Research Database (Denmark)

    Mears, Lisa; Stocks, Stuart M.; Albaek, Mads O.

    2017-01-01

    A novel model-based control strategy has been developed for filamentous fungal fed-batch fermentation processes. The system of interest is a pilot scale (550 L) filamentous fungus process operating at Novozymes A/S. In such processes, it is desirable to maximize the total product achieved...... is recursively updated using on-line measurements. The model was applied in order to predict the current system states, including the biomass concentration, and to simulate the expected future trajectory of the system until a specified end time. In this way, the desired feed rate is updated along the progress...

  20. Catchment & sewer network simulation model to benchmark control strategies within urban wastewater systems

    DEFF Research Database (Denmark)

    Saagi, Ramesh; Flores Alsina, Xavier; Fu, Guangtao

    2016-01-01

    This paper aims at developing a benchmark simulation model to evaluate control strategies for the urban catchment and sewer network. Various modules describing wastewater generation in the catchment, its subsequent transport and storage in the sewer system are presented. Global/local overflow based...... evaluation criteria describing the cumulative and acute effects are presented. Simulation results show that the proposed set of models is capable of generating daily, weekly and seasonal variations as well as describing the effect of rain events on wastewater characteristics. Two sets of case studies...

  1. Transformation Strategies between Block-Oriented and Graph-Oriented Process Modelling Languages

    DEFF Research Database (Denmark)

    Mendling, Jan; Lassen, Kristian Bisgaard; Zdun, Uwe

    to abstract from concrete transformationstrategies by distinguishing two major paradigms for process modelling languages:block-oriented languages (such as BPEL and BPML) and graph-oriented languages(such as EPCs and YAWL). The contribution of this paper are generic strategiesfor transforming from block......Much recent research work discusses the transformation between differentprocess modelling languages. This work, however, is mainly focussed on specific processmodelling languages, and thus the general reusability of the applied transformationconcepts is rather limited. In this paper, we aim......-oriented process languages to graph-oriented languages,and vice versa. We also present two case studies of applying our strategies....

  2. Modeling nitrate-nitrogen load reduction strategies for the des moines river, iowa using SWAT

    Science.gov (United States)

    Schilling, K.E.; Wolter, C.F.

    2009-01-01

    The Des Moines River that drains a watershed of 16,175 km2 in portions of Iowa and Minnesota is impaired for nitrate-nitrogen (nitrate) due to concentrations that exceed regulatory limits for public water supplies. The Soil Water Assessment Tool (SWAT) model was used to model streamflow and nitrate loads and evaluate a suite of basin-wide changes and targeting configurations to potentially reduce nitrate loads in the river. The SWAT model comprised 173 subbasins and 2,516 hydrologic response units and included point and nonpoint nitrogen sources. The model was calibrated for an 11-year period and three basin-wide and four targeting strategies were evaluated. Results indicated that nonpoint sources accounted for 95% of the total nitrate export. Reduction in fertilizer applications from 170 to 50 kg/ha achieved the 38% reduction in nitrate loads, exceeding the 34% reduction required. In terms of targeting, the most efficient load reductions occurred when fertilizer applications were reduced in subbasins nearest the watershed outlet. The greatest load reduction for the area of land treated was associated with reducing loads from 55 subbasins with the highest nitrate loads, achieving a 14% reduction in nitrate loads achieved by reducing applications on 30% of the land area. SWAT model results provide much needed guidance on how to begin implementing load reduction strategies most efficiently in the Des Moines River watershed. ?? 2009 Springer Science+Business Media, LLC.

  3. Developing a Sustainability Assessment Model to Analyze China’s Municipal Solid Waste Management Enhancement Strategy

    Directory of Open Access Journals (Sweden)

    Hua Li

    2015-01-01

    Full Text Available This study develops a sustainability assessment model for analysis and decision-making of the impact of China’s municipal solid waste management enhancement strategy options based on three waste treatment scenarios: landfill disposal, waste-to-energy incineration, and a combination of a material recovery facility and composting. The model employs life cycle assessment, health risk assessment, and full cost accounting to evaluate the treatment scenarios regarding safeguarding public health, protecting the environment and conserving resources, and economic feasibility. The model then uses an analytic hierarchy process for an overall appraisal of sustainability. Results suggest that a combination of material recovery and composting is the most efficient option. The study results clarify sustainable attributes, suitable predications, evaluation modeling, and stakeholder involvement issues in solid waste management. The demonstration of the use of sustainability assessment model (SAM provides flexibility by allowing assessment for a municipal solid waste management (MSWM strategy on a case-by-case basis, taking into account site-specific factors, therefore it has the potential for flexible applications in different communities/regions.

  4. Modeling nitrate-nitrogen load reduction strategies for the Des Moines River, Iowa using SWAT.

    Science.gov (United States)

    Schilling, Keith E; Wolter, Calvin F

    2009-10-01

    The Des Moines River that drains a watershed of 16,175 km(2) in portions of Iowa and Minnesota is impaired for nitrate-nitrogen (nitrate) due to concentrations that exceed regulatory limits for public water supplies. The Soil Water Assessment Tool (SWAT) model was used to model streamflow and nitrate loads and evaluate a suite of basin-wide changes and targeting configurations to potentially reduce nitrate loads in the river. The SWAT model comprised 173 subbasins and 2,516 hydrologic response units and included point and nonpoint nitrogen sources. The model was calibrated for an 11-year period and three basin-wide and four targeting strategies were evaluated. Results indicated that nonpoint sources accounted for 95% of the total nitrate export. Reduction in fertilizer applications from 170 to 50 kg/ha achieved the 38% reduction in nitrate loads, exceeding the 34% reduction required. In terms of targeting, the most efficient load reductions occurred when fertilizer applications were reduced in subbasins nearest the watershed outlet. The greatest load reduction for the area of land treated was associated with reducing loads from 55 subbasins with the highest nitrate loads, achieving a 14% reduction in nitrate loads achieved by reducing applications on 30% of the land area. SWAT model results provide much needed guidance on how to begin implementing load reduction strategies most efficiently in the Des Moines River watershed.

  5. Model Identifikasi Risiko dan Strategi Peningkatan Nilai Tambah pada Rantai Pasok Kelapa Sawit

    Directory of Open Access Journals (Sweden)

    Syarif Hidayat

    2012-01-01

    Full Text Available The actors in the palm oil supply chain industry are the farmers, traders, crude palm oil (CPO factories, frying-oil factories (refineries, distributors and the consumers. The farmers sell fresh fruit bunches (FFB to the CPO factories through traders. FFB is converted into CPO which is later sold to the refineries. Refineries convert CPO into frying oil which is sold to the consumers through the distributors. There are risks due to product quality consistency, price fluctuation and supply chain continuity. This study has two objectives: (1 to develop a model to identify, evaluate and rank the risks, (2 to develop a model to identify and rank the strategies in improving their added value. Data for this study was obtained through direct interviews and questionnaires. The respondents were selected experts and industry players. The data were processed using Fuzzy Analytic Hierarchy Process (FAHP models. The first FAHP model showed that the two most important risks were the supply chain continuity and product quality. The second FAHP model showed that the recommended strategies to improve the added values of the actors were the improvement of the infrastructure/cluster development, followed by the usage of superior seeds and cultivation techniques.

  6. The Models of Applying Online Privacy Literacy Strategies: A Case Study of Instagram Girl Users

    Directory of Open Access Journals (Sweden)

    Abdollah Bicharanlou

    2017-09-01

    Full Text Available Social networks affect remarkably in the lives of virtual space users. These networks like most human relations involve compromising between self-disclosure and privacy protection. A process which is realized through improving privacy and empowering the user at the personal level. This study aimed to assess strategies based on online privacy literacy. In particular, strategies that Instagram young girls users should employ to achieve the optimum level of privacy. For this purpose, firstly the paradox of privacy, benefits and risks of self-disclosure are explained, then according to online privacy literacy, some social and technological strategies are introduced by which users can solve the “paradox of privacy.” In the result section, after describing the main benefits and risks of self-disclosure by girl users, the current models of using these social and technological strategies to solve the mentioned paradox are discussed. The research method is ethnography based on non-collaborative observation of Instagram pages and semi-structured interviews with 20 girl users of social networks.

  7. The influence of ligament modelling strategies on the predictive capability of finite element models of the human knee joint.

    Science.gov (United States)

    Naghibi Beidokhti, Hamid; Janssen, Dennis; van de Groes, Sebastiaan; Hazrati, Javad; Van den Boogaard, Ton; Verdonschot, Nico

    2017-12-08

    In finite element (FE) models knee ligaments can represented either by a group of one-dimensional springs, or by three-dimensional continuum elements based on segmentations. Continuum models closer approximate the anatomy, and facilitate ligament wrapping, while spring models are computationally less expensive. The mechanical properties of ligaments can be based on literature, or adjusted specifically for the subject. In the current study we investigated the effect of ligament modelling strategy on the predictive capability of FE models of the human knee joint. The effect of literature-based versus specimen-specific optimized material parameters was evaluated. Experiments were performed on three human cadaver knees, which were modelled in FE models with ligaments represented either using springs, or using continuum representations. In spring representation collateral ligaments were each modelled with three and cruciate ligaments with two single-element bundles. Stiffness parameters and pre-strains were optimized based on laxity tests for both approaches. Validation experiments were conducted to evaluate the outcomes of the FE models. Models (both spring and continuum) with subject-specific properties improved the predicted kinematics and contact outcome parameters. Models incorporating literature-based parameters, and particularly the spring models (with the representations implemented in this study), led to relatively high errors in kinematics and contact pressures. Using a continuum modelling approach resulted in more accurate contact outcome variables than the spring representation with two (cruciate ligaments) and three (collateral ligaments) single-element-bundle representations. However, when the prediction of joint kinematics is of main interest, spring ligament models provide a faster option with acceptable outcome. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. A Robust Longitudinal Control Strategy of Platoons under Model Uncertainties and Time Delays

    Directory of Open Access Journals (Sweden)

    Na Chen

    2018-01-01

    Full Text Available Automated vehicles are designed to free drivers from driving tasks and are expected to improve traffic safety and efficiency when connected via vehicle-to-vehicle communication, that is, connected automated vehicles (CAVs. The time delays and model uncertainties in vehicle control systems pose challenges for automated driving in real world. Ignoring them may render the performance of cooperative driving systems unsatisfactory or even unstable. This paper aims to design a robust and flexible platooning control strategy for CAVs. A centralized control method is presented, where the leader of a CAV platoon collects information from followers, computes the desired accelerations of all controlled vehicles, and broadcasts the desired accelerations to followers. The robust platooning is formulated as a Min-Max Model Predictive Control (MM-MPC problem, where optimal accelerations are generated to minimize the cost function under the worst case, where the worst case is taken over the possible models. The proposed method is flexible in such a way that it can be applied to both homogeneous platoon and heterogeneous platoon with mixed human-driven and automated controlled vehicles. A third-order linear vehicle model with fixed feedback delay and stochastic actuator lag is used to predict the platoon behavior. Actuator lag is assumed to vary randomly with unknown distributions but a known upper bound. The controller regulates platoon accelerations over a time horizon to minimize a cost function representing driving safety, efficiency, and ride comfort, subject to speed limits, plausible acceleration range, and minimal net spacing. The designed strategy is tested by simulating homogeneous and heterogeneous platoons in a number of typical and extreme scenarios to assess the system stability and performance. The test results demonstrate that the designed control strategy for CAV can ensure the robustness of stability and performance against model uncertainties

  9. State-Dependent Impulsive Control Strategies for a Tumor-Immune Model

    Directory of Open Access Journals (Sweden)

    Kwang Su Kim

    2016-01-01

    Full Text Available Controlling the number of tumor cells leads us to expect more efficient strategies for treatment of tumor. Towards this goal, a tumor-immune model with state-dependent impulsive treatments is established. This model may give an efficient treatment schedule to control tumor’s abnormal growth. By using the Poincaré map and analogue of Poincaré criterion, some conditions for the existence and stability of a positive order-1 periodic solution of this model are obtained. Moreover, we carry out numerical simulations to illustrate the feasibility of our main results and compare fixed-time impulsive treatment effects with state-dependent impulsive treatment effects. The results of our simulations say that, in determining optimal treatment timing, the model with state-dependent impulsive control is more efficient than that with fixed-time impulsive control.

  10. Evolution of flowering strategies in Oenothera glazioviana: an integral projection model approach.

    Science.gov (United States)

    Rees, Mark; Rose, Karen E

    2002-07-22

    The timing of reproduction is a key determinant of fitness. Here, we develop parameterized integral projection models of size-related flowering for the monocarpic perennial Oenothera glazioviana and use these to predict the evolutionarily stable strategy (ESS) for flowering. For the most part there is excellent agreement between the model predictions and the results of quantitative field studies. However, the model predicts a much steeper relationship between plant size and the probability of flowering than observed in the field, indicating selection for a 'threshold size' flowering function. Elasticity and sensitivity analysis of population growth rate lambda and net reproductive rate R(0) are used to identify the critical traits that determine fitness and control the ESS for flowering. Using the fitted model we calculate the fitness landscape for invading genotypes and show that this is characterized by a ridge of approximately equal fitness. The implications of these results for the maintenance of genetic variation are discussed.

  11. Assessment and Intervention in Overcoming Writing Difficulties: An Illustration From the Self-Regulated Strategy Development Model.

    Science.gov (United States)

    Graham, Steve; Harris, Karen R

    1999-07-01

    The progress of a 12-year-old boy with learning disabilities and severe writing difficulties is followed from initial assessment through instruction in strategies for planning, revising, and managing the composing process. A validated instructional model, Self-Regulated Strategy Development (SRSD), was used to teach these processes. With SRSD, writing strategies are explicitly taught in combination with procedures for regulating the use of these strategies, the writing process, and any undesirable behaviors that may impede performance. Recommendations are offered to speech-language pathologists for applying the SRSD model to children experiencing writing difficulties.

  12. Modelling heavy metals build-up on urban road surfaces for effective stormwater reuse strategy implementation

    International Nuclear Information System (INIS)

    Hong, Nian; Zhu, Panfeng; Liu, An

    2017-01-01

    Urban road stormwater is an alternative water resource to mitigate water shortage issues in the worldwide. Heavy metals deposited (build-up) on urban road surface can enter road stormwater runoff, undermining stormwater reuse safety. As heavy metal build-up loads perform high variabilities in terms of spatial distribution and is strongly influenced by surrounding land uses, it is essential to develop an approach to identify hot-spots where stormwater runoff could include high heavy metal concentrations and hence cannot be reused if it is not properly treated. This study developed a robust modelling approach to estimating heavy metal build-up loads on urban roads using land use fractions (representing percentages of land uses within a given area) by an artificial neural network (ANN) model technique. Based on the modelling results, a series of heavy metal load spatial distribution maps and a comprehensive ecological risk map were generated. These maps provided a visualization platform to identify priority areas where the stormwater can be safely reused. Additionally, these maps can be utilized as an urban land use planning tool in the context of effective stormwater reuse strategy implementation. - Highlights: • A model was developed to simulate heavy metal build-up loads on urban roads. • This model is based on artificial neural networks. • Land use fractions was used to model build-up loads on different particle sizes. • The maps of heavy metal spatial distribution and ecological risk were generated. • This model can be used for effective stormwater reuse strategy implementation. - Development of a robust modelling approach to mapping heavy metals build-up and their ecological risks for stormwater reuse safety.

  13. Why Is Improvement of Earth System Models so Elusive? Challenges and Strategies from Dust Aerosol Modeling

    Science.gov (United States)

    Miller, Ronald L.; Garcia-Pando, Carlos Perez; Perlwitz, Jan; Ginoux, Paul

    2015-01-01

    Past decades have seen an accelerating increase in computing efficiency, while climate models are representing a rapidly widening set of physical processes. Yet simulations of some fundamental aspects of climate like precipitation or aerosol forcing remain highly uncertain and resistant to progress. Dust aerosol modeling of soil particles lofted by wind erosion has seen a similar conflict between increasing model sophistication and remaining uncertainty. Dust aerosols perturb the energy and water cycles by scattering radiation and acting as ice nuclei, while mediating atmospheric chemistry and marine photosynthesis (and thus the carbon cycle). These effects take place across scales from the dimensions of an ice crystal to the planetary-scale circulation that disperses dust far downwind of its parent soil. Representing this range leads to several modeling challenges. Should we limit complexity in our model, which consumes computer resources and inhibits interpretation? How do we decide if a process involving dust is worthy of inclusion within our model? Can we identify a minimal representation of a complex process that is efficient yet retains the physics relevant to climate? Answering these questions about the appropriate degree of representation is guided by model evaluation, which presents several more challenges. How do we proceed if the available observations do not directly constrain our process of interest? (This could result from competing processes that influence the observed variable and obscure the signature of our process of interest.) Examples will be presented from dust modeling, with lessons that might be more broadly applicable. The end result will either be clinical depression or there assuring promise of continued gainful employment as the community confronts these challenges.

  14. Modeling of novel diagnostic strategies for active tuberculosis - a systematic review: current practices and recommendations.

    Directory of Open Access Journals (Sweden)

    Alice Zwerling

    Full Text Available The field of diagnostics for active tuberculosis (TB is rapidly developing. TB diagnostic modeling can help to inform policy makers and support complicated decisions on diagnostic strategy, with important budgetary implications. Demand for TB diagnostic modeling is likely to increase, and an evaluation of current practice is important. We aimed to systematically review all studies employing mathematical modeling to evaluate cost-effectiveness or epidemiological impact of novel diagnostic strategies for active TB.Pubmed, personal libraries and reference lists were searched to identify eligible papers. We extracted data on a wide variety of model structure, parameter choices, sensitivity analyses and study conclusions, which were discussed during a meeting of content experts.From 5619 records a total of 36 papers were included in the analysis. Sixteen papers included population impact/transmission modeling, 5 were health systems models, and 24 included estimates of cost-effectiveness. Transmission and health systems models included specific structure to explore the importance of the diagnostic pathway (n = 4, key determinants of diagnostic delay (n = 5, operational context (n = 5, and the pre-diagnostic infectious period (n = 1. The majority of models implemented sensitivity analysis, although only 18 studies described multi-way sensitivity analysis of more than 2 parameters simultaneously. Among the models used to make cost-effectiveness estimates, most frequent diagnostic assays studied included Xpert MTB/RIF (n = 7, and alternative nucleic acid amplification tests (NAATs (n = 4. Most (n = 16 of the cost-effectiveness models compared new assays to an existing baseline and generated an incremental cost-effectiveness ratio (ICER.Although models have addressed a small number of important issues, many decisions regarding implementation of TB diagnostics are being made without the full benefits of insight from mathematical

  15. Why Is Improvement of Earth System Models So Elusive? Challenges and Strategies From Dust Aerosol Modeling

    Science.gov (United States)

    Miller, R. L.; Pérez García-Pando, C.; Perlwitz, J. P.; Ginoux, P. A.

    2015-12-01

    Past decades have seen an accelerating increase in computing efficiency,while climate models are representing a rapidly widening set ofphysical processes. Yet simulations of some fundamental aspects ofclimate like precipitation or aerosol forcing remain highly uncertainand resistent to progress. Dust aerosol modeling of soil particleslofted by wind erosion has seen a similar conflict between increasingmodel sophistication and remaining uncertainty. Dust aerosols perturbthe energy and water cycles by scattering radiation and acting as icenuclei, while mediating atmospheric chemistry and marinephotosynthesis (and thus the carbon cycle). These effects take placeacross scales from the dimensions of an ice crystal to theplanetary-scale circulation that disperses dust far downwind of itsparent soil. Representing this range leads to several modelingchallenges. Should we limit complexity in our model, which consumescomputer resources and inhibits interpretation? How do we decide if aprocess involving dust is worthy of inclusion within our model? Canwe identify a minimal representation of a complex process that isefficient yet retains the physics relevant to climate? Answeringthese questions about the appropriate degree of representation isguided by model evaluation, which presents several more challenges.How do we proceed if the available observations do not directlyconstrain our process of interest? (This could result from competingprocesses that influence the observed variable and obscure thesignature of our process of interest.) Examples will be presentedfrom dust modeling, with lessons that might be more broadlyapplicable. The end result will either be clinical depression or thereassuring promise of continued gainful employment as the communityconfronts these challenges.

  16. A risk based model supporting long term maintenance and reinvestment strategy decision making

    Energy Technology Data Exchange (ETDEWEB)

    Sand, Kjell; Montard, Julien; Tremoen, Tord H.

    2010-02-15

    This Technical Report is a product from the project Risk-Based Distribution System Asset Management (short: RISK DSAM) - Work Package 3 Risk exposure on company/strategic level. In the report a concept for portfolio distribution system asset management is presented. The approach comprises four main steps: 1. Decide the asset base. 2. Divide the asset base into relevant archetypes. 3. Develop or select relevant maintenance and reinvestment strategies for the different archetypes. 4. Estimate risks and costs for each archetype for the relevant strategies. For the different steps guidelines are given and a proposal for implementation of the concept is given in terms of a proposed IT system architecture.To evaluate the feasibility of such a concept, a prototype was developed in by using Visual Basic macros in Excel using real technical data from a small DSO. The experience from using the prototype shows that the concept is realistic. All assets are included and depending of the ambition of the risk analysis both simple simulation models and more advanced might be embedded. Presentations of the concept for a utility engineers have receive positive feedback indicating that the concept is regarded as a practical way to develop risk based asset management strategies for the asset fleet. It should be noted that the concept should be applied on a company strategic level and is thus not designed to be applied for a specific project or asset decisions. For this, more detailed models with area specific information, topology etc. are needed. (Author)

  17. ANIMATION STRATEGIES FOR SMOOTH TRANSFORMATIONS BETWEEN DISCRETE LODS OF 3D BUILDING MODELS

    Directory of Open Access Journals (Sweden)

    M. Kada

    2016-06-01

    Full Text Available The cartographic 3D visualization of urban areas has experienced tremendous progress over the last years. An increasing number of applications operate interactively in real-time and thus require advanced techniques to improve the quality and time response of dynamic scenes. The main focus of this article concentrates on the discussion of strategies for smooth transformation between two discrete levels of detail (LOD of 3D building models that are represented as restricted triangle meshes. Because the operation order determines the geometrical and topological properties of the transformation process as well as its visual perception by a human viewer, three different strategies are proposed and subsequently analyzed. The simplest one orders transformation operations by the length of the edges to be collapsed, while the other two strategies introduce a general transformation direction in the form of a moving plane. This plane either pushes the nodes that need to be removed, e.g. during the transformation of a detailed LOD model to a coarser one, towards the main building body, or triggers the edge collapse operations used as transformation paths for the cartographic generalization.

  18. Animation Strategies for Smooth Transformations Between Discrete Lods of 3d Building Models

    Science.gov (United States)

    Kada, Martin; Wichmann, Andreas; Filippovska, Yevgeniya; Hermes, Tobias

    2016-06-01

    The cartographic 3D visualization of urban areas has experienced tremendous progress over the last years. An increasing number of applications operate interactively in real-time and thus require advanced techniques to improve the quality and time response of dynamic scenes. The main focus of this article concentrates on the discussion of strategies for smooth transformation between two discrete levels of detail (LOD) of 3D building models that are represented as restricted triangle meshes. Because the operation order determines the geometrical and topological properties of the transformation process as well as its visual perception by a human viewer, three different strategies are proposed and subsequently analyzed. The simplest one orders transformation operations by the length of the edges to be collapsed, while the other two strategies introduce a general transformation direction in the form of a moving plane. This plane either pushes the nodes that need to be removed, e.g. during the transformation of a detailed LOD model to a coarser one, towards the main building body, or triggers the edge collapse operations used as transformation paths for the cartographic generalization.

  19. An advanced Lithium-ion battery optimal charging strategy based on a coupled thermoelectric model

    International Nuclear Information System (INIS)

    Liu, Kailong; Li, Kang; Yang, Zhile; Zhang, Cheng; Deng, Jing

    2017-01-01

    Lithium-ion batteries are widely adopted as the power supplies for electric vehicles. A key but challenging issue is to achieve optimal battery charging, while taking into account of various constraints for safe, efficient and reliable operation. In this paper, a triple-objective function is first formulated for battery charging based on a coupled thermoelectric model. An advanced optimal charging strategy is then proposed to develop the optimal constant-current-constant-voltage (CCCV) charge current profile, which gives the best trade-off among three conflicting but important objectives for battery management. To be specific, a coupled thermoelectric battery model is first presented. Then, a specific triple-objective function consisting of three objectives, namely charging time, energy loss, and temperature rise (both the interior and surface), is proposed. Heuristic methods such as Teaching-learning-based-optimization (TLBO) and particle swarm optimization (PSO) are applied to optimize the triple-objective function, and their optimization performances are compared. The impacts of the weights for different terms in the objective function are then assessed. Experimental results show that the proposed optimal charging strategy is capable of offering desirable effective optimal charging current profiles and a proper trade-off among the conflicting objectives. Further, the proposed optimal charging strategy can be easily extended to other battery types.

  20. Modeling seasonal water balance based on catchments' hedging strategy on evapotranspiration for climate seasonality

    Science.gov (United States)

    Wu, S.; Zhao, J.; Wang, H.

    2017-12-01

    This paper develops a seasonal water balance model based on the hypothesis that natural catchments utilize hedging strategy on evapotranspiration for climate seasonality. According to the monthly aridity index, one year is split into wet season and dry season. A seasonal water balance model is developed by analogy to a two-stage reservoir operation model, in which seasonal rainfall infiltration, evapotranspiration and saturation-excess runoff is corresponding to the inflow, release and surplus of the catchment system. Then the optimal hedging between wet season and dry season evapotranspiration is analytically derived with marginal benefit principle. Water budget data sets of 320 catchments in the United States covering the period from 1980 to 2010 are used to evaluate the performance of this model. The Nash-Sutcliffe Efficiency coefficient for evapotranspiration is higher than 0.5 in 84% of the study catchments; while the runoff is 87%. This paper validates catchments' hedging strategy on evapotranspiration for climate seasonality and shows its potential application for seasonal water balance, which is valuable for water resources planning and management.

  1. Public protection strategies in the event of a nuclear reactor accident: multicompartment ventilation model for shelters

    International Nuclear Information System (INIS)

    Aldrich, D.C.; Ericson, D.M. Jr.

    1978-01-01

    A multicompartment ventilation model has been presented for the calculation of airborne radioactive material concentrations internal to structures. The model was used to estimate the potential effectiveness of sheltering in reducing the dose due to inhaled radionuclides. The sensitivity of the model to parameter values and protection strategies was discussed. Using ''best estimate'' values for the model parameters, this analysis indicated that sheltered individuals received a reduction of 35 percent in the dose from inhaled radionuclides. Larger reductions would be possible if lower values of the ventilation rate n, could be achieved by either tighter building construction or emergency sealing of openings in the structure. Such emergency means could include taping windows, placing wet paper over cracks, etc. Further analysis indicated that the strategy of opening doors and windows, turning on ventilating systems, etc., in an attempt to ''air-out'' the structure after the cloud of radioactive material had passed will most likely not contribute significantly to reduction in dose due to inhaled radionuclides unless very low initial ventilation rates are achieved. Although the available data did not allow quantitative predictions of dose reductions afforded by basements or other appropriately sealed-off rooms, preliminary analysis indicated qualitatively that they could be significant

  2. A critical review of cell culture strategies for modelling intracortical brain implant material reactions.

    Science.gov (United States)

    Gilmour, A D; Woolley, A J; Poole-Warren, L A; Thomson, C E; Green, R A

    2016-06-01

    The capacity to predict in vivo responses to medical devices in humans currently relies greatly on implantation in animal models. Researchers have been striving to develop in vitro techniques that can overcome the limitations associated with in vivo approaches. This review focuses on a critical analysis of the major in vitro strategies being utilized in laboratories around the world to improve understanding of the biological performance of intracortical, brain-implanted microdevices. Of particular interest to the current review are in vitro models for studying cell responses to penetrating intracortical devices and their materials, such as electrode arrays used for brain computer interface (BCI) and deep brain stimulation electrode probes implanted through the cortex. A background on the neural interface challenge is presented, followed by discussion of relevant in vitro culture strategies and their advantages and disadvantages. Future development of 2D culture models that exhibit developmental changes capable of mimicking normal, postnatal development will form the basis for more complex accurate predictive models in the future. Although not within the scope of this review, innovations in 3D scaffold technologies and microfluidic constructs will further improve the utility of in vitro approaches. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. A matrix game model for analyzing FTR bidding strategies in deregulated electric power markets

    International Nuclear Information System (INIS)

    Das, Tapas K.; Rocha, Patricio; Babayigit, Cihan

    2010-01-01

    Suppliers in deregulated electric power markets compete for financial transmission rights (FTRs) to hedge against congestion charges. The system operator receives the bids for FTRs submitted by the suppliers and develops an allocation strategy by solving an optimization model. Each FTR bid is defined by a path, a quantity indicating the amount of FTRs the supplier is bidding for in that path, and the price that the supplier is willing to pay for each FTR. The FTR revenue is calculated only after the electricity market has been cleared by computing the differences in the LMPs at the pair of nodes that connect each path. Thus, suppliers rely on forecasts of locational marginal prices (LMPs) to develop their FTR bids. In this paper, we present a game theoretic modeling approach to develop FTR bidding strategies for power suppliers assuming that they have forecasts of LMPs. The game theoretic model considers multiple participants as well as network contingencies. We apply the game theoretic model on a sample network to assess impacts of variations of bid and network parameters on the FTR market outcome. (author)

  4. Methodology of synchronization among strategy and operation. A standards-based modeling approach

    Directory of Open Access Journals (Sweden)

    VICTOR EDWIN COLLAZOS

    2017-05-01

    Full Text Available Enterprise Architecture (EA has gained importance in recent years, mainly for its concept of “alignment” between the strategic and operational levels of organizations. Such alignment occurs when Information Technology (IT is applied correctly and timely, working in synergy and harmony with strategy and the operation to achieve mutually their own goals and satisfy the organizational needs.Both the strategic and operational levels have standards that help model elements necessary to obtain desired results. In this sense, BMM and BPMN were selected because both have the support of OMG and they are fairly well known for modelling the strategic level and operational level, respectively. In addition, i* modeling goal can be used for reducing the gap between these two standards. This proposal may help both the high-level design of the information system and to the appropriate identification of the business processes that will support it.This paper presents a methodology for aligning strategy and the operation based on standards and heuristics. We have made a classification for elements of the models and, for some specific cases, an extension of the heuristics associated between them. This allows us to propose methodology, which uses above-mentioned standards and combines mappings, transformations and actions to be considered in the alignment process.

  5. Limited sampling strategy models for estimating the AUC of gliclazide in Chinese healthy volunteers.

    Science.gov (United States)

    Huang, Ji-Han; Wang, Kun; Huang, Xiao-Hui; He, Ying-Chun; Li, Lu-Jin; Sheng, Yu-Cheng; Yang, Juan; Zheng, Qing-Shan

    2013-06-01

    The aim of this work is to reduce the cost of required sampling for the estimation of the area under the gliclazide plasma concentration versus time curve within 60 h (AUC0-60t ). The limited sampling strategy (LSS) models were established and validated by the multiple regression model within 4 or fewer gliclazide concentration values. Absolute prediction error (APE), root of mean square error (RMSE) and visual prediction check were used as criterion. The results of Jack-Knife validation showed that 10 (25.0 %) of the 40 LSS based on the regression analysis were not within an APE of 15 % using one concentration-time point. 90.2, 91.5 and 92.4 % of the 40 LSS models were capable of prediction using 2, 3 and 4 points, respectively. Limited sampling strategies were developed and validated for estimating AUC0-60t of gliclazide. This study indicates that the implementation of an 80 mg dosage regimen enabled accurate predictions of AUC0-60t by the LSS model. This study shows that 12, 6, 4, 2 h after administration are the key sampling times. The combination of (12, 2 h), (12, 8, 2 h) or (12, 8, 4, 2 h) can be chosen as sampling hours for predicting AUC0-60t in practical application according to requirement.

  6. KAJIAN STRATEGI DAN PROGRAM PERBAIKAN OPERASIONALISASI DARI MILK DISTRICT MODEL NESTLÉ DI JAWA TIMUR

    Directory of Open Access Journals (Sweden)

    Bambang Ali Nugroho

    2012-06-01

    Full Text Available The objective of this study was to explore the improvement of Nestle milk district model in East Java. Secondary data on dairy development in East Java was used to analyse internal and external factors. SWOT analysis method was used to evaluate existing condition of dairy development in East Java and to build a recomended strategy to improve milk district model. In simplest terms, setting up a milk district involved: a negotiating agreements with farmers for twice-daily collection of their milk, b installing chilling centers in the larger community and collection points in the villages or adapting existing collection infrastructure, c arranging transportation from collection centers to the district’s factory, and d implementing a program to improve milk quality. In reality building a milk district model is not core business or core competence of Nestle but its something absolutely necessary to be introduced. After this program have been introduced, the smallscale dairy farmers were capable to organise themselves to produce freshmilk. Nestle have introduced various insentive systems to support smallscale dairy farmers capacity to guarantee that they have self responsability in dairy farming activities have positive impacts on productivity, quality product and product safety, that all that aspects will give benefit to Nestle. (Key words: Milk district model, Dairy farmer, Dairy cooperative, Milk processing industry, Strategy, Program

  7. ANALYTICAL MODELING OF INNOVATIVE SENSOR PLACEMENT STRATEGY FOR CORONA-BASED WIRELESS SENSOR NETWORKS

    Directory of Open Access Journals (Sweden)

    HASSAN H. EKAL

    2017-09-01

    Full Text Available Wireless Sensor Networks (WSNs applications are increasing rapidly, thanks to their broad potential in ecological monitoring, biomedical health monitoring, data gathering and many others. Imbalance energy of sensors causes significant reduction in the lifetime of the network. In many-to-one communication (corona WSNs, sensor nodes located nearby the data collector (sink forward data sensed data received from other nodes, hence, having heavier workloads. These nodes consume more energy than the others, leading to quicker energy depletion.Consequently, this results in energy hole problem, where the network becomes separate islands, which affect the lifetime of the network negatively. When this situation occurs, the sensed data will not be forwarded to the intended sink; accordingly, the network will not be able to completely fulfil its required tasks. In this paper, an effective sensors placement strategy is proposed to avoid or alleviate energy hole problem in such type of WSNs. The proposed strategy aims to improve, scale, and balance the energy consumption among sensor nodes and to maximize the network lifetime, by sustaining the network coverage and connectivity. To achieve this aim, the number of sensors should be optimized to create sub-balanced coronas in the sense of energy consumption, while satisfying the network coverage and connectivity requirements. The theoretical design and modelling of the proposed sensors placement strategy promise a considerable improvement in the lifetime of corona-based networks. The Experimental evaluation results have shown that the proposed sensors placement strategy is capable to increase the network lifetime considerably compared to conventional uniform strategy.

  8. Barriers and strategies to an iterative model of advance care planning communication.

    Science.gov (United States)

    Ahluwalia, Sangeeta C; Bekelman, David B; Huynh, Alexis K; Prendergast, Thomas J; Shreve, Scott; Lorenz, Karl A

    2015-12-01

    Early and repeated patient-provider conversations about advance care planning (ACP) are now widely recommended. We sought to characterize barriers and strategies for realizing an iterative model of ACP patient-provider communication. A total of 2 multidisciplinary focus groups and 3 semistructured interviews with 20 providers at a large Veterans Affairs medical center. Thematic analysis was employed to identify salient themes. Barriers included variation among providers in approaches to ACP, lack of useful information about patient values to guide decision making, and ineffective communication between providers across settings. Strategies included eliciting patient values rather than specific treatment choices and an increased role for primary care in the ACP process. Greater attention to connecting providers across the continuum, maximizing the potential of the electronic health record, and linking patient experiences to their values may help to connect ACP communication across the continuum. © The Author(s) 2014.

  9. Affective strategies, attitudes, and a model of speaking performance development for engineering students

    Science.gov (United States)

    Wijirahayu, S.; Dorand, P.

    2018-01-01

    Learning English as a Foreign language (EFL) as one of the challenges especially for students majoring in Telecommunication Engineering to develop their communication skill as a professional could be one of the chances for them to face a more global era. Yet, there are important factors that may influence the progress of the speaking performance and attitude is one of them. Therefore, a survey involving two main psychological variables in language learning namely attitude and affective strategies and the third variable is speaking performance was conducted and a model of affective strategies in language learning developing through the application of Content Language Integrated Learning and multimedia instruction was introduced. This study involved 71 sophomore students and two classes of university students majoring in Telecommunication Engineering and Electrical Engineering. The researchers used both survey and action research method with quantitative as well as qualitative in approach.

  10. An Optimal Investment Strategy and Multiperiod Deposit Insurance Pricing Model for Commercial Banks

    Directory of Open Access Journals (Sweden)

    Grant E. Muller

    2018-01-01

    Full Text Available We employ the method of stochastic optimal control to derive the optimal investment strategy for maximizing an expected exponential utility of a commercial bank’s capital at some future date T>0. In addition, we derive a multiperiod deposit insurance (DI pricing model that incorporates the explicit solution of the optimal control problem and an asset value reset rule comparable to the typical practice of insolvency resolution by insuring agencies. By way of numerical simulations, we study the effects of changes in the DI coverage horizon, the risk associated with the asset portfolio of the bank, and the bank’s initial leverage level (deposit-to-asset ratio on the DI premium while the optimal investment strategy is followed.

  11. Deduction of initial strategy distributions of agents in mix-game models

    Science.gov (United States)

    Gou, Chengling

    2006-11-01

    This paper reports the effort of deducing the initial strategy distributions (ISDs) of agents in mix-game models that is used to predict a real financial time series generated from a target financial market. Using mix-games to predict Shanghai Index, we find that the time series of prediction accurate rates is sensitive to the ISDs of agents in group 2 who play a minority game, but less sensitive to the ISDs of agents in group 1 who play a majority game. And agents in group 2 tend to cluster in full strategy space (FSS) if the real financial time series has obvious tendency (upward or downward), otherwise they tend to scatter in FSS. We also find that the ISDs and the number of agents in group 1 influence the level of prediction accurate rates. Finally, this paper gives suggestion about further research.

  12. Multistrain models predict sequential multidrug treatment strategies to result in less antimicrobial resistance than combination treatment

    DEFF Research Database (Denmark)

    Ahmad, Amais; Zachariasen, Camilla; Christiansen, Lasse Engbo

    2016-01-01

    generated by a mathematical model of the competitive growth of multiple strains of Escherichia coli.Results: Simulation studies showed that sequential use of tetracycline and ampicillin reduced the level of double resistance, when compared to the combination treatment. The effect of the cycling frequency...... frequency did not play a role in suppressing the growth of resistant strains, but the specific order of the two antimicrobials did. Predictions made from the study could be used to redesign multidrug treatment strategies not only for intramuscular treatment in pigs, but also for other dosing routes.......Background: Combination treatment is increasingly used to fight infections caused by bacteria resistant to two or more antimicrobials. While multiple studies have evaluated treatment strategies to minimize the emergence of resistant strains for single antimicrobial treatment, fewer studies have...

  13. A Reactive Power Based Reference Model for Adaptive Control Strategy in a SEIG

    Directory of Open Access Journals (Sweden)

    M. A. Taghikhani

    2018-02-01

    Full Text Available In this paper, a new control strategy is proposed for a three-phase squirrel-cage self-excited induction generator (SEIG connected to a variable speed wind turbine in autonomous mode. In order to improve the dynamic performance of the mentioned vector control system, a model reference adaptive controller is used for online rotor time constant estimation. Thus, the main drawbacks of this method, which include the effects of the changes in machine parameters on rotor flux estimation, slip speed, the creation of instability problems and the system leaving vector control mode, are resolved. In this control strategy, a PI controller is used to control the dc voltage and three similar hysteresis current controllers (HCC are used to control the switching of IGBTs. The results of the dynamic simulation indicate the desirable performance of the proposed system.

  14. Identification of Constitutive Parameters Using Inverse Strategy Coupled to an ANN Model

    International Nuclear Information System (INIS)

    Aguir, H.; Chamekh, A.; BelHadjSalah, H.; Hambli, R.

    2007-01-01

    This paper deals with the identification of material parameters using an inverse strategy. In the classical methods, the inverse technique is generally coupled with a finite element code which leads to a long computing time. In this work an inverse strategy coupled with an ANN procedure is proposed. This method has the advantage of being faster than the classical one. To validate this approach an experimental plane tensile and bulge tests are used in order to identify material behavior. The ANN model is trained from finite element simulations of the two tests. In order to reduce the gap between the experimental responses and the numerical ones, the proposed method is coupled with an optimization procedure to identify material parameters for the AISI304. The identified material parameters are the hardening curve and the anisotropic coefficients

  15. Multi-granularity immunization strategy based on SIRS model in scale-free network

    Science.gov (United States)

    Nian, Fuzhong; Wang, Ke

    2015-04-01

    In this paper, a new immunization strategy was established to prevent the epidemic spreading based on the principle of "Multi-granularity" and "Pre-warning Mechanism", which send different pre-warning signal with the risk rank of the susceptible node to be infected. The pre-warning means there is a higher risk that the susceptible node is more likely to be infected. The multi-granularity means the susceptible node is linked with multi-infected nodes. In our model, the effect of the different situation of the multi-granularity immunizations is compared and different spreading rates are adopted to describe the epidemic behavior of nodes. In addition the threshold value of epidemic outbreak is investigated, which makes the result more convincing. The theoretical analysis and the simulations indicate that the proposed immunization strategy is effective and it is also economic and feasible.

  16. Towards the Adriatic meteotsunami early warning system: modelling strategy and validation

    Science.gov (United States)

    Denamiel, Clea; Šepić, Jadranka; Vilibić, Ivica

    2017-04-01

    Destructive meteotsunamis are known to occur along the eastern Adriatic coastal areas and islands (Vilibić and Šepić, 2009). The temporal lag between the offshore generation of meteotsunamis due to specific atmospheric conditions and the arrival of a dangerous nearshore propagating wave at known locations is of the order of tens of minutes to a couple of hours. In order to reduce the coastal risk for the coastal communities, an early warning system must rely on the ability to detect these extreme storms offshore with in-situ measurements and to predict the hydrodynamic response nearshore via numerical models within this short time lag. However, the numerical modelling of meteotsunamis requires both temporal and spatial high-resolution atmospheric and ocean models which are highly demanding concerning time and computer resources. Furthermore, both a multi-model approach and an ensemble modelling strategy should be used to better forecast the distribution of the nearshore impact of meteotsunamis. The modelling strategy used in this study thus rely on the development of an operational atmosphere-ocean model of the Adriatic Sea at 1km spatial resolution based on the state-of-the-art fully coupled COAWST model (Warner et al., 2010). The model allows for generation of meteotsunamis offshore, while various high-resolution (up to 5m) nearshore hydrodynamic models (such as ADCIRC - Luettich and Westerink, 1991; SELFE - Zhang et al., 2008 and GeoClaw - LeVeque, 2012) are setup to properly reproduce meteotsunami dynamics of the entire Croatian coastal areas, which are characterized by a great number of islands, channels and bays. The implementation and validation of each component of this modelling system is first undertaken for the well documented meteotsunami event (Šepić et al., 2016), which was recorded along the Croatian Adriatic coast on the 25th and the 26th of June 2014. The validation of the modelling strategy as well as the model results is presented and

  17. Particle Reduction Strategies - PAREST. Traffic emission modelling. Model comparision and alternative scenarios. Sub-report

    International Nuclear Information System (INIS)

    Kugler, Ulrike; Theloke, Jochen; Joerss, Wolfram

    2013-01-01

    The modeling of the reference scenario and the various reduction scenarios in PAREST was based on the Central System of Emissions (CSE) (CSE, 2007). Emissions from road traffic were calculated by using the traffic emission model TREMOD (Knoerr et al., 2005) and fed into the CSE. The version TREMOD 4.17 has been used. The resulting emission levels in PAREST reference scenario were supplemented by the emission-reducing effect of the implementation of the future Euro 5 and 6 emission standards for cars and light commercial vehicles and Euro VI for heavy commercial vehicles in combination with the truck toll extension. [de

  18. Multiple-point statistical simulation for hydrogeological models: 3-D training image development and conditioning strategies

    Science.gov (United States)

    Høyer, Anne-Sophie; Vignoli, Giulio; Mejer Hansen, Thomas; Thanh Vu, Le; Keefer, Donald A.; Jørgensen, Flemming

    2017-12-01

    Most studies on the application of geostatistical simulations based on multiple-point statistics (MPS) to hydrogeological modelling focus on relatively fine-scale models and concentrate on the estimation of facies-level structural uncertainty. Much less attention is paid to the use of input data and optimal construction of training images. For instance, even though the training image should capture a set of spatial geological characteristics to guide the simulations, the majority of the research still relies on 2-D or quasi-3-D training images. In the present study, we demonstrate a novel strategy for 3-D MPS modelling characterized by (i) realistic 3-D training images and (ii) an effective workflow for incorporating a diverse group of geological and geophysical data sets. The study covers an area of 2810 km2 in the southern part of Denmark. MPS simulations are performed on a subset of the geological succession (the lower to middle Miocene sediments) which is characterized by relatively uniform structures and dominated by sand and clay. The simulated domain is large and each of the geostatistical realizations contains approximately 45 million voxels with size 100 m × 100 m × 5 m. Data used for the modelling include water well logs, high-resolution seismic data, and a previously published 3-D geological model. We apply a series of different strategies for the simulations based on data quality, and develop a novel method to effectively create observed spatial trends. The training image is constructed as a relatively small 3-D voxel model covering an area of 90 km2. We use an iterative training image development strategy and find that even slight modifications in the training image create significant changes in simulations. Thus, this study shows how to include both the geological environment and the type and quality of input information in order to achieve optimal results from MPS modelling. We present a practical workflow to build the training image and

  19. Trading strategies modeling in Colombian power market using artificial intelligence techniques

    International Nuclear Information System (INIS)

    Moreno, Julian

    2009-01-01

    The aim of this paper is to present a model based on fuzzy logic and machine learning in order to maximize the profits of Colombian energy trade agents according to their risk profile. The model has two parts, the first one is a fuzzy expert system that gives a recommendation about the trade strategy these agents should follow, and whose definition depends mainly on market conditions. The second one is a reinforced learning mechanism with which the agents 'learn' when they perceive the consequences of their actions, so they modify such actions looking for a reward not just in short but also in long-term. The whole model is validated using actual data as well as a simulation approach using synthetic time series for some relevant variables as hydraulic availability, energy pool price and bilateral contracts price. (author)

  20. Humanized mice: models for evaluating NeuroHIV and cure strategies.

    Science.gov (United States)

    Honeycutt, Jenna B; Garcia, J Victor

    2018-04-01

    While the human immunodeficiency virus (HIV) epidemic was initially characterized by a high prevalence of severe and widespread neurological pathologies, the development of better treatments to suppress viremia over years and even decades has mitigated many of the severe neurological pathologies previously observed. Despite effective treatment, mild neurocognitive impairment and premature cognitive aging are observed in HIV-infected individuals, suggesting a changing but ongoing role of HIV infection in the central nervous system (CNS). Although current therapies are effective in suppressing viremia, they are not curative and patients must remain on life-long treatment or risk recrudescence of virus. Important for the development and evaluation of a cure for HIV will be animal models that recapitulate critical aspects of infection in vivo. In the following, we seek to summarize some of the recent developments in humanized mouse models and their usefulness in modeling HIV infection of the CNS and HIV cure strategies.

  1. Trading strategies modeling in Colombian power market using artificial intelligence techniques

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Julian [Escuela de Sistemas, Universidad Nacional de Colombia, Carrera 80 No. 65-223 Bloque M8A Medellin (Colombia)

    2009-03-15

    The aim of this paper is to present a model based on fuzzy logic and machine learning in order to maximize the profits of Colombian energy trade agents according to their risk profile. The model has two parts, the first one is a fuzzy expert system that gives a recommendation about the trade strategy these agents should follow, and whose definition depends mainly on market conditions. The second one is a reinforced learning mechanism with which the agents 'learn' when they perceive the consequences of their actions, so they modify such actions looking for a reward not just in short but also in long-term. The whole model is validated using actual data as well as a simulation approach using synthetic time series for some relevant variables as hydraulic availability, energy pool price and bilateral contracts price. (author)

  2. A Petri net-based modelling of replacement strategies under technological obsolescence

    Energy Technology Data Exchange (ETDEWEB)

    Clavareau, Julien [Universite Libre de Bruxelles (U.L.B.), Service de Metrologie Nucleaire, Av. F.D. Roosevelt, 50 (CP165/84), Bruxelles B-1050 (Belgium)], E-mail: jclavare@ulb.ac.be; Labeau, Pierre-Etienne [Universite Libre de Bruxelles (U.L.B.), Service de Metrologie Nucleaire, Av. F.D. Roosevelt, 50 (CP165/84), Bruxelles B-1050 (Belgium)

    2009-02-15

    The technological obsolescence of a unit is characterised by the existence of challenger units displaying identical functionalities, but with higher performances. Though this issue is commonly encountered in practice, it has received little consideration in the literature. Previous exploratory works have treated the problem of replacing old-technology items by new ones, for identical components facing a unique new generation of items. This paper aims to define, in a realistic way, possible replacement policies when several types of challenger units are available and when the performances of these newly available units improve with time. Since no fully generic model can exist in maintenance optimisation, a modular modelling of the problem, allowing easy adaptations to features corresponding to specific applications is highly desirable. This work therefore proposes a modular Petri net model for this problem, underlying a Monte Carlo (MC) estimation of the costs incurred by the different possible replacement strategies under consideration.

  3. Equilibrium Model of Discrete Dynamic Supply Chain Network with Random Demand and Advertisement Strategy

    Directory of Open Access Journals (Sweden)

    Guitao Zhang

    2014-01-01

    Full Text Available The advertisement can increase the consumers demand; therefore it is one of the most important marketing strategies in the operations management of enterprises. This paper aims to analyze the impact of advertising investment on a discrete dynamic supply chain network which consists of suppliers, manufactures, retailers, and demand markets associated at different tiers under random demand. The impact of advertising investment will last several planning periods besides the current period due to delay effect. Based on noncooperative game theory, variational inequality, and Lagrange dual theory, the optimal economic behaviors of the suppliers, the manufactures, the retailers, and the consumers in the demand markets are modeled. In turn, the supply chain network equilibrium model is proposed and computed by modified project contraction algorithm with fixed step. The effectiveness of the model is illustrated by numerical examples, and managerial insights are obtained through the analysis of advertising investment in multiple periods and advertising delay effect among different periods.

  4. The Robust Control Mixer Method for Reconfigurable Control Design By Using Model Matching Strategy

    DEFF Research Database (Denmark)

    Yang, Z.; Blanke, Mogens; Verhagen, M.

    2001-01-01

    This paper proposes a robust reconfigurable control synthesis method based on the combination of the control mixer method and robust H1 con- trol techniques through the model-matching strategy. The control mixer modules are extended from the conventional matrix-form into the LTI sys- tem form....... By regarding the nominal control system as the desired model, an augmented control system is constructed through the model-matching formulation, such that the current robust control techniques can be usedto synthesize these dynamical modules. One extension of this method with respect to the performance...... recovery besides the functionality recovery is also discussed under this framework. Comparing with the conventional control mixer method, the proposed method considers the recon gured system's stability, performance and robustness simultaneously. Finally, the proposed method is illustrated by a case study...

  5. A strategy for modeling ground water rebound in abandoned deep mine systems.

    Science.gov (United States)

    Adams, R; Younger, P L

    2001-01-01

    Discharges of polluted water from abandoned mines are a major cause of degradation of water resources worldwide. Pollution arises after abandoned workings flood up to surface level, by the process termed ground water rebound. As flow in large, open mine voids is often turbulent, standard techniques for modeling ground water flow (which assume laminar flow) are inappropriate for predicting ground water rebound. More physically realistic models are therefore desirable, yet these are often expensive to apply to all but the smallest of systems. An overall strategy for ground water rebound modeling is proposed, with models of decreasing complexity applied as the temporal and spatial scales of the systems under analysis increase. For relatively modest systems (area modeling approach has been developed, in which 3-D pipe networks (representing major mine roadways, etc.) are routed through a variably saturated, 3-D porous medium (representing the country rock). For systems extending more than 100 to 3000 km2, a semidistributed model (GRAM) has been developed, which conceptualizes extensively interconnected volumes of workings as ponds, which are connected to other ponds only at discrete overflow points, such as major inter-mine roadways, through which flow can be efficiently modeled using the Prandtl-Nikuradse pipe-flow formulation. At the very largest scales, simple water-balance calculations are probably as useful as any other approach, and a variety of proprietary codes may be used for the purpose.

  6. Knowledge Co-production Strategies for Water Resources Modeling and Decision Making

    Science.gov (United States)

    Gober, P.

    2016-12-01

    The limited impact of scientific information on policy making and climate adaptation in North America has raised awareness of the need for new modeling strategies and knowledge transfer processes. This paper outlines the rationale for a new paradigm in water resources modeling and management, using examples from the USA and Canada. Principles include anticipatory modeling, complex system dynamics, decision making under uncertainty, visualization, capacity to represent and manipulate critical trade-offs, stakeholder engagement, local knowledge, context-specific activities, social learning, vulnerability analysis, iterative and collaborative modeling, and the concept of a boundary organization. In this framework, scientists and stakeholders are partners in the production and dissemination of knowledge for decision making, and local knowledge is fused with scientific observation and methodology. Discussion draws from experience in building long-term collaborative boundary organizations in Phoenix, Arizona in the USA and the Saskatchewan River Basin (SRB) in Canada. Examples of boundary spanning activities include the use of visualization, the concept of a decision theater, infrastructure to support social learning, social networks, and reciprocity, simulation modeling to explore "what if" scenarios of the future, surveys to elicit how water problems are framed by scientists and stakeholders, and humanistic activities (theatrical performances, art exhibitions, etc.) to draw attention to local water issues. The social processes surrounding model development and dissemination are at least as important as modeling assumptions, procedures, and results in determining whether scientific knowledge will be used effectively for water resources decision making.

  7. Modeling the language learning strategies and English language proficiency of pre-university students in UMS: A case study

    Science.gov (United States)

    Kiram, J. J.; Sulaiman, J.; Swanto, S.; Din, W. A.

    2015-10-01

    This study aims to construct a mathematical model of the relationship between a student's Language Learning Strategy usage and English Language proficiency. Fifty-six pre-university students of University Malaysia Sabah participated in this study. A self-report questionnaire called the Strategy Inventory for Language Learning was administered to them to measure their language learning strategy preferences before they sat for the Malaysian University English Test (MUET), the results of which were utilised to measure their English language proficiency. We attempted the model assessment specific to Multiple Linear Regression Analysis subject to variable selection using Stepwise regression. We conducted various assessments to the model obtained, including the Global F-test, Root Mean Square Error and R-squared. The model obtained suggests that not all language learning strategies should be included in the model in an attempt to predict Language Proficiency.

  8. The development and demonstration of integrated models for the evaluation of severe accident management strategies - SAMEM

    International Nuclear Information System (INIS)

    Ang, M.L.; Peers, K.; Kersting, E.; Fassmann, W.; Tuomisto, H.; Lundstroem, P.; Helle, M.; Gustavsson, V.; Jacobsson, P.

    2001-01-01

    This study is concerned with the further development of integrated models for the assessment of existing and potential severe accident management (SAM) measures. This paper provides a brief summary of these models, based on Probabilistic Safety Assessment (PSA) methods and the Risk Oriented Accident Analysis Methodology (ROAAM) approach, and their application to a number of case studies spanning both preventive and mitigative accident management regimes. In the course of this study it became evident that the starting point to guide the selection of methodology and any further improvement is the intended application. Accordingly, such features as the type and area of application and the confidence requirement are addressed in this project. The application of an integrated ROAAM approach led to the implementation, at the Loviisa NPP, of a hydrogen mitigation strategy, which requires substantial plant modifications. A revised level 2 PSA model was applied to the Sizewell B NPP to assess the feasibility of the in-vessel retention strategy. Similarly the application of PSA based models was extended to the Barseback and Ringhals 2 NPPs to improve the emergency operating procedures, notably actions related to manual operations. A human reliability analysis based on the Human Cognitive Reliability (HCR) and Technique For Human Error Rate (THERP) models was applied to a case study addressing secondary and primary bleed and feed procedures. Some aspects pertinent to the quantification of severe accident phenomena were further examined in this project. A comparison of the applications of PSA based approach and ROAAM to two severe accident issues, viz hydrogen combustion and in-vessel retention, was made. A general conclusion is that there is no requirement for further major development of the PSA and ROAAM methodologies in the modelling of SAM strategies for a variety of applications as far as the technical aspects are concerned. As is demonstrated in this project, the

  9. Near infrared spectroscopy to estimate the temperature reached on burned soils: strategies to develop robust models.

    Science.gov (United States)

    Guerrero, César; Pedrosa, Elisabete T.; Pérez-Bejarano, Andrea; Keizer, Jan Jacob

    2014-05-01

    The temperature reached on soils is an important parameter needed to describe the wildfire effects. However, the methods for measure the temperature reached on burned soils have been poorly developed. Recently, the use of the near-infrared (NIR) spectroscopy has been pointed as a valuable tool for this purpose. The NIR spectrum of a soil sample contains information of the organic matter (quantity and quality), clay (quantity and quality), minerals (such as carbonates and iron oxides) and water contents. Some of these components are modified by the heat, and each temperature causes a group of changes, leaving a typical fingerprint on the NIR spectrum. This technique needs the use of a model (or calibration) where the changes in the NIR spectra are related with the temperature reached. For the development of the model, several aliquots are heated at known temperatures, and used as standards in the calibration set. This model offers the possibility to make estimations of the temperature reached on a burned sample from its NIR spectrum. However, the estimation of the temperature reached using NIR spectroscopy is due to changes in several components, and cannot be attributed to changes in a unique soil component. Thus, we can estimate the temperature reached by the interaction between temperature and the thermo-sensible soil components. In addition, we cannot expect the uniform distribution of these components, even at small scale. Consequently, the proportion of these soil components can vary spatially across the site. This variation will be present in the samples used to construct the model and also in the samples affected by the wildfire. Therefore, the strategies followed to develop robust models should be focused to manage this expected variation. In this work we compared the prediction accuracy of models constructed with different approaches. These approaches were designed to provide insights about how to distribute the efforts needed for the development of robust

  10. Biofabrication strategies for 3D in vitro models and regenerative medicine

    Science.gov (United States)

    Moroni, Lorenzo; Burdick, Jason A.; Highley, Christopher; Lee, Sang Jin; Morimoto, Yuya; Takeuchi, Shoji; Yoo, James J.

    2018-05-01

    Organs are complex systems composed of different cells, proteins and signalling molecules that are arranged in a highly ordered structure to orchestrate a myriad of functions in our body. Biofabrication strategies can be applied to engineer 3D tissue models in vitro by mimicking the structure and function of native tissue through the precise deposition and assembly of materials and cells. This approach allows the spatiotemporal control over cell-cell and cell-extracellular matrix communication and thus the recreation of tissue-like structures. In this Review, we examine biofabrication strategies for the construction of functional tissue replacements and organ models, focusing on the development of biomaterials, such as supramolecular and photosensitive materials, that can be processed using biofabrication techniques. We highlight bioprinted and bioassembled tissue models and survey biofabrication techniques for their potential to recreate complex tissue properties, such as shape, vasculature and specific functionalities. Finally, we discuss challenges, such as scalability and the foreign body response, and opportunities in the field and provide an outlook to the future of biofabrication in regenerative medicine.

  11. A MODEL OF MANAGEMENT STRATEGY FOR A QUALITY LEARNING IN ISLAMIC HIGHER EDUCATION (IHE

    Directory of Open Access Journals (Sweden)

    Ara Hidayat

    2016-03-01

    Full Text Available The quality of Islamic education is generally influenced by several factors, among other things: leadership, organizational culture, lecturercompetence versus faculty student ratio, dynamic curriculum, library collections and learning facilities. The factors above are most likely to influence and impact the quality of education process in general. Developing a model of management strategy for quality learning is a minimal effort to improve quality graduates of a university. The model was developed on the basis of the following theories: (1 transformative leadership (Tichy and Devana (1997, (2 strategy of learning organization, (Peter (2002, and (3 a quality-based management (Griffin, 2004. Furthermore, the model shares the following characteristics: (1 a quality learning emerges from an effective and efficient management of academic service; (2 developing management of a quality learning is continuous lecture development; (3 lecture plays an important role in developing a quality learning; (4 a quality learning stipulates that a leader be loyal and committed to their job, wise and have a sense of democracy.

  12. Model-based power control strategy development of a fuel cell hybrid vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Haitao, Yun [School of Automobile and Traffic, Qingdao Technological University, Qingdao Shandong 266033 (China); School of Automobile, Tongji University, ShangHai 201804 (China); Yulan, Zhao [School of Automobile and Traffic, Qingdao Technological University, Qingdao Shandong 266033 (China); Zechang, Sun; Gang, Wan [School of Automobile, Tongji University, ShangHai 201804 (China)

    2008-06-01

    An integrated procedure for math modeling and power control strategy design for a fuel cell hybrid vehicle (FCHV) is presented in this paper. Dynamic math model of the powertrain is constructed firstly, which includes four modules: fuel cell engine, DC/DC inverter, motor-driver, and power battery. Based on the mathematic model, a power control principle is designed, which uses full-states closed-loop feedback algorithm. To implement full-states feedback, a Luenberger state observer is designed to estimate open circuit voltage (OCV) of the battery, which make the control principle not sensitive to the battery SOC (state of charge) estimated error. Full-states feedback controller is then designed through analyzing step responding of the powertrain and test data. At last of the paper, the results of simulation and field test are illustrated. The results show that the power control strategy designed takes into account the performance and economy characteristics of components of the FCHV powertrain and achieves the control object excellently. (author)

  13. Model For Marketing Strategy Decision Based On Multicriteria Decicion Making: A Case Study In Batik Madura Industry

    Science.gov (United States)

    Anna, I. D.; Cahyadi, I.; Yakin, A.

    2018-01-01

    Selection of marketing strategy is a prominent competitive advantage for small and medium enterprises business development. The selection process is is a multiple criteria decision-making problem, which includes evaluation of various attributes or criteria in a process of strategy formulation. The objective of this paper is to develop a model for the selection of a marketing strategy in Batik Madura industry. The current study proposes an integrated approach based on analytic network process (ANP) and technique for order preference by similarity to ideal solution (TOPSIS) to determine the best strategy for Batik Madura marketing problems. Based on the results of group decision-making technique, this study selected fourteen criteria, including consistency, cost, trend following, customer loyalty, business volume, uniqueness manpower, customer numbers, promotion, branding, bussiness network, outlet location, credibility and the inovation as Batik Madura marketing strategy evaluation criteria. A survey questionnaire developed from literature review was distributed to a sample frame of Batik Madura SMEs in Pamekasan. In the decision procedure step, expert evaluators were asked to establish the decision matrix by comparing the marketing strategy alternatives under each of the individual criteria. Then, considerations obtained from ANP and TOPSIS methods were applied to build the specific criteria constraints and range of the launch strategy in the model. The model in this study demonstrates that, under current business situation, Straight-focus marketing strategy is the best marketing strategy for Batik Madura SMEs in Pamekasan.

  14. Adapting a strategic management model to hospital operating strategies. A model development and justification.

    Science.gov (United States)

    Swinehart, K; Zimmerer, T W; Oswald, S

    1995-01-01

    Industrial organizations have employed the process of strategic management in their attempts to cope effectively with global competitive pressures, while attempting to build and maintain competitive advantage. With health-care organizations presently trying to cope with an increasingly turbulent environment created by the uncertainty as to pending legislation and anticipated reform, the need for such organizational strategic planning is apparent. Presents and discusses a methodology for adapting a business-oriented model of strategic planning to health care.

  15. Analisis Strategi Mitigasi Resiko Pada Supply Chain CV Surya Cip Dengan House of Risk Model

    OpenAIRE

    Pertiwi, Yoana Ellen; Susanty, Aries

    2017-01-01

    Analysis of Risk Mitigation Strategies on CV Surya CIP's Supply Chain Using House of Risk Model. In the supply chain activities always has the potential of risk, therefore risk management is necessary for handling the risks. At the company that produces plastic molding machine such as CV Surya CIP, in its supply chain activities have a chance to arise risks. The purpose of this study is to identify the various risks that occur in the CV Surya CIP and its causes, severity and determine the ...

  16. Improving Student Learning Outcomes Marketing Strategy Lesson By Applying SFAE Learning Model

    Directory of Open Access Journals (Sweden)

    Winda Nur Rohmawati

    2017-11-01

    Full Text Available Research objectives for improving student learning outcomes on the subjects of marketing strategy through the implementation of model learning SFAE. This type of research this is a class action research using a qualitative approach which consists of two cycles with the subject Marketing X grade SMK YPI Darussalam 2 Cerme Gresik Regency. This research consists of four stages: (1 the Planning Act, (2 the implementation of the action, (3 observations (observation, and (4 Reflection. The result of the research shows that cognitive and affective learning outcomes of students have increased significantly.

  17. A novel model-based control strategy for aerobic filamentous fungal fed-batch fermentation processes.

    Science.gov (United States)

    Mears, Lisa; Stocks, Stuart M; Albaek, Mads O; Cassells, Benny; Sin, Gürkan; Gernaey, Krist V

    2017-07-01

    A novel model-based control strategy has been developed for filamentous fungal fed-batch fermentation processes. The system of interest is a pilot scale (550 L) filamentous fungus process operating at Novozymes A/S. In such processes, it is desirable to maximize the total product achieved in a batch in a defined process time. In order to achieve this goal, it is important to maximize both the product concentration, and also the total final mass in the fed-batch system. To this end, we describe the development of a control strategy which aims to achieve maximum tank fill, while avoiding oxygen limited conditions. This requires a two stage approach: (i) calculation of the tank start fill; and (ii) on-line control in order to maximize fill subject to oxygen transfer limitations. First, a mechanistic model was applied off-line in order to determine the appropriate start fill for processes with four different sets of process operating conditions for the stirrer speed, headspace pressure, and aeration rate. The start fills were tested with eight pilot scale experiments using a reference process operation. An on-line control strategy was then developed, utilizing the mechanistic model which is recursively updated using on-line measurements. The model was applied in order to predict the current system states, including the biomass concentration, and to simulate the expected future trajectory of the system until a specified end time. In this way, the desired feed rate is updated along the progress of the batch taking into account the oxygen mass transfer conditions and the expected future trajectory of the mass. The final results show that the target fill was achieved to within 5% under the maximum fill when tested using eight pilot scale batches, and over filling was avoided. The results were reproducible, unlike the reference experiments which show over 10% variation in the final tank fill, and this also includes over filling. The variance of the final tank fill is

  18. Modelling and Evaluation of Heating Strategies for High Temperature Polymer Electrolyte Membrane Fuel Cell Stacks

    DEFF Research Database (Denmark)

    Andreasen, Søren Juhl; Kær, Søren Knudsen

    2008-01-01

    Experiments were conducted on two different cathode air cooled high temperature PEM (HTPEM) fuel cell stacks; a 30 cell 400W prototype stack using two bipolar plates per cell, and a 65 cell 1 kW commercial stack using one bipolar plate per cell. The work seeks to examine the use of different...... model to simulate the temperature development of a fuel cell stack during heating can be used for assistance in system and control design. The heating strategies analyzed and tested reduced the startup time of one of the fuel cell stacks from 1 h to about 6 min....

  19. Challenges of implementing economic model predictive control strategy for buildings interacting with smart energy systems

    DEFF Research Database (Denmark)

    Zong, Yi; Böning, Georg Martin; Santos, Rui Mirra

    2016-01-01

    ) strategy for energy management in smart buildings, which can act as active users interacting with smart energy systems. The challenges encountered during the implementation of EMPC for active demand side management are investigated in detail in this paper. A pilot testing study shows energy savings......When there is a high penetration of renewables in the energy system, it requires proactive control of large numbers of distributed demand response resources to maintain the system’s reliability and improve its operational economics. This paper presents the Economic Model Predictive Control (EMPC...

  20. MODEL ОF CONSUMER BEHAVIOR TRANSFORMATION AS A BASIS FOR MARKETING STRATEGY

    Directory of Open Access Journals (Sweden)

    V.Savelyev

    2014-09-01

    Full Text Available The article concerns with the basic consumer segments. The consumer needs are analyzed in the article and the model of change in consumer behavior is created. The article proposes the recommendations on effective strategic actions in order to competitive capacity increase. It is determined that in low purchasing power conditions, focus on meeting the needs of loyal customer segments will allow companies to increase the competitiveness of the market supply. Adaptation of marketing strategy in low purchasing power conditions is a creative process in which success is based on the orientation of the changed consumption motives.