WorldWideScience

Sample records for return vehicle input

  1. Mars Sample Return: Mars Ascent Vehicle Mission and Technology Requirements

    Science.gov (United States)

    Bowles, Jeffrey V.; Huynh, Loc C.; Hawke, Veronica M.; Jiang, Xun J.

    2013-01-01

    A Mars Sample Return mission is the highest priority science mission for the next decade recommended by the recent Decadal Survey of Planetary Science, the key community input process that guides NASAs science missions. A feasibility study was conducted of a potentially simple and low cost approach to Mars Sample Return mission enabled by the use of developing commercial capabilities. Previous studies of MSR have shown that landing an all up sample return mission with a high mass capacity lander is a cost effective approach. The approach proposed is the use of an emerging commercially available capsule to land the launch vehicle system that would return samples to Earth. This paper describes the mission and technology requirements impact on the launch vehicle system design, referred to as the Mars Ascent Vehicle (MAV).

  2. Mars Earth Return Vehicle (MERV) Propulsion Options

    Science.gov (United States)

    Oleson, Steven R.; McGuire, Melissa L.; Burke, Laura; Fincannon, James; Warner, Joe; Williams, Glenn; Parkey, Thomas; Colozza, Tony; Fittje, Jim; Martini, Mike; hide

    2010-01-01

    The COMPASS Team was tasked with the design of a Mars Sample Return Vehicle. The current Mars sample return mission is a joint National Aeronautics and Space Administration (NASA) and European Space Agency (ESA) mission, with ESA contributing the launch vehicle for the Mars Sample Return Vehicle. The COMPASS Team ran a series of design trades for this Mars sample return vehicle. Four design options were investigated: Chemical Return /solar electric propulsion (SEP) stage outbound, all-SEP, all chemical and chemical with aerobraking. The all-SEP and Chemical with aerobraking were deemed the best choices for comparison. SEP can eliminate both the Earth flyby and the aerobraking maneuver (both considered high risk by the Mars Sample Return Project) required by the chemical propulsion option but also require long low thrust spiral times. However this is offset somewhat by the chemical/aerobrake missions use of an Earth flyby and aerobraking which also take many months. Cost and risk analyses are used to further differentiate the all-SEP and Chemical/Aerobrake options.

  3. Influence of Road Excitation and Steering Wheel Input on Vehicle System Dynamic Responses

    Directory of Open Access Journals (Sweden)

    Zhen-Feng Wang

    2017-06-01

    Full Text Available Considering the importance of increasing driving safety, the study of safety is a popular and critical topic of research in the vehicle industry. Vehicle roll behavior with sudden steering input is a main source of untripped rollover. However, previous research has seldom considered road excitation and its coupled effect on vehicle lateral response when focusing on lateral and vertical dynamics. To address this issue, a novel method was used to evaluate effects of varying road level and steering wheel input on vehicle roll behavior. Then, a 9 degree of freedom (9-DOF full-car roll nonlinear model including vertical and lateral dynamics was developed to study vehicle roll dynamics with or without of road excitation. Based on a 6-DOF half-car roll model and 9-DOF full-car nonlinear model, relationship between three-dimensional (3-D road excitation and various steering wheel inputs on vehicle roll performance was studied. Finally, an E-Class (SUV level car model in CARSIM® was used, as a benchmark, with and without road input conditions. Both half-car and full-car models were analyzed under steering wheel inputs of 5°, 10° and 15°. Simulation results showed that the half-car model considering road input was found to have a maximum accuracy of 65%. Whereas, the full-car model had a minimum accuracy of 85%, which was significantly higher compared to the half-car model under the same scenario.

  4. Road simulation for four-wheel vehicle whole input power spectral density

    Science.gov (United States)

    Wang, Jiangbo; Qiang, Baomin

    2017-05-01

    As the vibration of running vehicle mainly comes from road and influence vehicle ride performance. So the road roughness power spectral density simulation has great significance to analyze automobile suspension vibration system parameters and evaluate ride comfort. Firstly, this paper based on the mathematical model of road roughness power spectral density, established the integral white noise road random method. Then in the MATLAB/Simulink environment, according to the research method of automobile suspension frame from simple two degree of freedom single-wheel vehicle model to complex multiple degrees of freedom vehicle model, this paper built the simple single incentive input simulation model. Finally the spectrum matrix was used to build whole vehicle incentive input simulation model. This simulation method based on reliable and accurate mathematical theory and can be applied to the random road simulation of any specified spectral which provides pavement incentive model and foundation to vehicle ride performance research and vibration simulation.

  5. Crew emergency return vehicle - Electrical power system design study

    Science.gov (United States)

    Darcy, E. C.; Barrera, T. P.

    1989-01-01

    A crew emergency return vehicle (CERV) is proposed to perform the lifeboat function for the manned Space Station Freedom. This escape module will be permanently docked to Freedom and, on demand, will be capable of safely returning the crew to earth. The unique requirements that the CERV imposes on its power source are presented, power source options are examined, and a baseline system is selected. It consists of an active Li-BCX DD-cell modular battery system and was chosen for the maturity of its man-rated design and its low development costs.

  6. Distribution of return point memory states for systems with stochastic inputs

    International Nuclear Information System (INIS)

    Amann, A; Brokate, M; Rachinskii, D; Temnov, G

    2011-01-01

    We consider the long term effect of stochastic inputs on the state of an open loop system which exhibits the so-called return point memory. An example of such a system is the Preisach model; more generally, systems with the Preisach type input-state relationship, such as in spin-interaction models, are considered. We focus on the characterisation of the expected memory configuration after the system has been effected by the input for sufficiently long period of time. In the case where the input is given by a discrete time random walk process, or the Wiener process, simple closed form expressions for the probability density of the vector of the main input extrema recorded by the memory state, and scaling laws for the dimension of this vector, are derived. If the input is given by a general continuous Markov process, we show that the distribution of previous memory elements can be obtained from a Markov chain scheme which is derived from the solution of an associated one-dimensional escape type problem. Formulas for transition probabilities defining this Markov chain scheme are presented. Moreover, explicit formulas for the conditional probability densities of previous main extrema are obtained for the Ornstein-Uhlenbeck input process. The analytical results are confirmed by numerical experiments.

  7. Overview of the Mars Sample Return Earth Entry Vehicle

    Science.gov (United States)

    Dillman, Robert; Corliss, James

    2008-01-01

    NASA's Mars Sample Return (MSR) project will bring Mars surface and atmosphere samples back to Earth for detailed examination. Langley Research Center's MSR Earth Entry Vehicle (EEV) is a core part of the mission, protecting the sample container during atmospheric entry, descent, and landing. Planetary protection requirements demand a higher reliability from the EEV than for any previous planetary entry vehicle. An overview of the EEV design and preliminary analysis is presented, with a follow-on discussion of recommended future design trade studies to be performed over the next several years in support of an MSR launch in 2018 or 2020. Planned topics include vehicle size for impact protection of a range of sample container sizes, outer mold line changes to achieve surface sterilization during re-entry, micrometeoroid protection, aerodynamic stability, thermal protection, and structural materials selection.

  8. Influence of Road Excitation and Steering Wheel Input on Vehicle System Dynamic Responses

    OpenAIRE

    Zhen-Feng Wang; Ming-Ming Dong; Liang Gu; Jagat-Jyoti Rath; Ye-Chen Qin; Bin Bai

    2017-01-01

    Considering the importance of increasing driving safety, the study of safety is a popular and critical topic of research in the vehicle industry. Vehicle roll behavior with sudden steering input is a main source of untripped rollover. However, previous research has seldom considered road excitation and its coupled effect on vehicle lateral response when focusing on lateral and vertical dynamics. To address this issue, a novel method was used to evaluate effects of varying road level and steer...

  9. Design and Control of a Multiple Input DC/DC Converter for Battery/Ultra-capacitor Based Electric Vehicle Power System

    DEFF Research Database (Denmark)

    Schaltz, Erik; Li, Zhihao; Onar, Omer

    2009-01-01

    Battery/Ultra-capacitor based electrical vehicles (EV) combine two energy sources with different voltage levels and current characteristics. This paper focuses on design and control of a multiple input DC/DC converter, to regulate output voltage from different inputs. The proposed multi-input con......Battery/Ultra-capacitor based electrical vehicles (EV) combine two energy sources with different voltage levels and current characteristics. This paper focuses on design and control of a multiple input DC/DC converter, to regulate output voltage from different inputs. The proposed multi...

  10. Mars ascent propulsion options for small sample return vehicles

    International Nuclear Information System (INIS)

    Whitehead, J. C.

    1997-01-01

    An unprecedented combination of high propellant fraction and small size is required for affordable-scale Mars return, regardless of the number of stages, or whether Mars orbit rendezvous or in-situ propellant options are used. Conventional space propulsion technology is too heavy, even without structure or other stage subsystems. The application of launch vehicle design principles to the development of new hardware on a tiny scale is therefore suggested. Miniature pump-fed rocket engines fed by low pressure tanks can help to meet this challenge. New concepts for engine cycles using piston pumps are described, and development issues are outlined

  11. Compressed Air Production Using Vehicle Suspension

    Directory of Open Access Journals (Sweden)

    Ninad Arun Malpure

    2015-08-01

    Full Text Available Abstract Generally compressed air is produced using different types of air compressors which consumes lot of electric energy and is noisy. In this paper an innovative idea is put forth for production of compressed air using movement of vehicle suspension which normal is wasted. The conversion of the force energy into the compressed air is carried out by the mechanism which consists of the vehicle suspension system hydraulic cylinder Non-return valve air compressor and air receiver. We are collecting air in the cylinder and store this energy into the tank by simply driving the vehicle. This method is non-conventional as no fuel input is required and is least polluting.

  12. Adaptive control of a quadrotor aerial vehicle with input constraints and uncertain parameters

    Science.gov (United States)

    Tran, Trong-Toan; Ge, Shuzhi Sam; He, Wei

    2018-05-01

    In this paper, we address the problem of adaptive bounded control for the trajectory tracking of a Quadrotor Aerial Vehicle (QAV) while the input saturations and uncertain parameters with the known bounds are simultaneously taken into account. First, to deal with the underactuated property of the QAV model, we decouple and construct the QAV model as a cascaded structure which consists of two fully actuated subsystems. Second, to handle the input constraints and uncertain parameters, we use a combination of the smooth saturation function and smooth projection operator in the control design. Third, to ensure the stability of the overall system of the QAV, we develop the technique for the cascaded system in the presence of both the input constraints and uncertain parameters. Finally, the region of stability of the closed-loop system is constructed explicitly, and our design ensures the asymptotic convergence of the tracking errors to the origin. The simulation results are provided to illustrate the effectiveness of the proposed method.

  13. Vehicle charging and return current measurements during electron-beam emission experiments from the Shuttle Orbiter

    International Nuclear Information System (INIS)

    Hawkins, J.G.

    1988-01-01

    The prime objective of this research was to investigate the electro-dynamic response of the Shuttle Orbiter during electron beam emission from the payload bay. This investigation has been conducted by examining data collected by the Vehicle Charging And Potential (VCAP) Experiment. The VCAP experiment has flown on two Shuttle missions with a Fast Pulse Electron Generator (FPEG) capable of emitting a 100 mA beam of 1 keV electrons. Diagnostics of the charging and return current during beam emission were provided by a combined Charge and Current Probe (CCP) located in the payload bay of the Orbiter. The CCP measurements were used to conduct a parametric study of the vehicle charging and return current as a function of vehicle attitude, ambient plasma parameters, and emitted beam current. In particular, the CCP measurements were found to depend strongly on the ambient plasma density. The vehicle charging during a 100 mA beam emission was small when the predicted ambient plasma density was greater than 3 x 10 5 cm -3 , but appreciable charging occurred when the density was less than this value. These observations indicated that the effective current-collecting area of the Orbiter is approximately 42 m 2 , consistent with estimates for the effective area of the Orbiter's engine nozzles. The operation of the Orbiter's Reaction Control System thrusters can create perturbations in the Orbiter's neutral and plasma environment that affect the CCP measurements. The CCP signatures of thruster firings are quite complex, but in general they are consistent with the depletion of plasma density in the ram direction and the enhancement of plasma density in the Orbiter's wake

  14. Fully self-contained vision-aided navigation and landing of a micro air vehicle independent from external sensor inputs

    Science.gov (United States)

    Brockers, Roland; Susca, Sara; Zhu, David; Matthies, Larry

    2012-06-01

    Direct-lift micro air vehicles have important applications in reconnaissance. In order to conduct persistent surveillance in urban environments, it is essential that these systems can perform autonomous landing maneuvers on elevated surfaces that provide high vantage points without the help of any external sensor and with a fully contained on-board software solution. In this paper, we present a micro air vehicle that uses vision feedback from a single down looking camera to navigate autonomously and detect an elevated landing platform as a surrogate for a roof top. Our method requires no special preparation (labels or markers) of the landing location. Rather, leveraging the planar character of urban structure, the landing platform detection system uses a planar homography decomposition to detect landing targets and produce approach waypoints for autonomous landing. The vehicle control algorithm uses a Kalman filter based approach for pose estimation to fuse visual SLAM (PTAM) position estimates with IMU data to correct for high latency SLAM inputs and to increase the position estimate update rate in order to improve control stability. Scale recovery is achieved using inputs from a sonar altimeter. In experimental runs, we demonstrate a real-time implementation running on-board a micro aerial vehicle that is fully self-contained and independent from any external sensor information. With this method, the vehicle is able to search autonomously for a landing location and perform precision landing maneuvers on the detected targets.

  15. Fuzzy portfolio model with fuzzy-input return rates and fuzzy-output proportions

    Science.gov (United States)

    Tsaur, Ruey-Chyn

    2015-02-01

    In the finance market, a short-term investment strategy is usually applied in portfolio selection in order to reduce investment risk; however, the economy is uncertain and the investment period is short. Further, an investor has incomplete information for selecting a portfolio with crisp proportions for each chosen security. In this paper we present a new method of constructing fuzzy portfolio model for the parameters of fuzzy-input return rates and fuzzy-output proportions, based on possibilistic mean-standard deviation models. Furthermore, we consider both excess or shortage of investment in different economic periods by using fuzzy constraint for the sum of the fuzzy proportions, and we also refer to risks of securities investment and vagueness of incomplete information during the period of depression economics for the portfolio selection. Finally, we present a numerical example of a portfolio selection problem to illustrate the proposed model and a sensitivity analysis is realised based on the results.

  16. An Efficient Approach for Mars Sample Return Using Emerging Commercial Capabilities.

    Science.gov (United States)

    Gonzales, Andrew A; Stoker, Carol R

    2016-06-01

    Mars Sample Return is the highest priority science mission for the next decade as recommended by the 2011 Decadal Survey of Planetary Science [1]. This article presents the results of a feasibility study for a Mars Sample Return mission that efficiently uses emerging commercial capabilities expected to be available in the near future. The motivation of our study was the recognition that emerging commercial capabilities might be used to perform Mars Sample Return with an Earth-direct architecture, and that this may offer a desirable simpler and lower cost approach. The objective of the study was to determine whether these capabilities can be used to optimize the number of mission systems and launches required to return the samples, with the goal of achieving the desired simplicity. All of the major element required for the Mars Sample Return mission are described. Mission system elements were analyzed with either direct techniques or by using parametric mass estimating relationships. The analysis shows the feasibility of a complete and closed Mars Sample Return mission design based on the following scenario: A SpaceX Falcon Heavy launch vehicle places a modified version of a SpaceX Dragon capsule, referred to as "Red Dragon", onto a Trans Mars Injection trajectory. The capsule carries all the hardware needed to return to Earth Orbit samples collected by a prior mission, such as the planned NASA Mars 2020 sample collection rover. The payload includes a fully fueled Mars Ascent Vehicle; a fueled Earth Return Vehicle, support equipment, and a mechanism to transfer samples from the sample cache system onboard the rover to the Earth Return Vehicle. The Red Dragon descends to land on the surface of Mars using Supersonic Retropropulsion. After collected samples are transferred to the Earth Return Vehicle, the single-stage Mars Ascent Vehicle launches the Earth Return Vehicle from the surface of Mars to a Mars phasing orbit. After a brief phasing period, the Earth Return

  17. F-18 High Alpha Research Vehicle (HARV) parameter identification flight test maneuvers for optimal input design validation and lateral control effectiveness

    Science.gov (United States)

    Morelli, Eugene A.

    1995-01-01

    Flight test maneuvers are specified for the F-18 High Alpha Research Vehicle (HARV). The maneuvers were designed for open loop parameter identification purposes, specifically for optimal input design validation at 5 degrees angle of attack, identification of individual strake effectiveness at 40 and 50 degrees angle of attack, and study of lateral dynamics and lateral control effectiveness at 40 and 50 degrees angle of attack. Each maneuver is to be realized by applying square wave inputs to specific control effectors using the On-Board Excitation System (OBES). Maneuver descriptions and complete specifications of the time/amplitude points define each input are included, along with plots of the input time histories.

  18. A MARKED POINT PROCESS MODEL FOR VEHICLE DETECTION IN AERIAL LIDAR POINT CLOUDS

    Directory of Open Access Journals (Sweden)

    A. Börcs

    2012-07-01

    Full Text Available In this paper we present an automated method for vehicle detection in LiDAR point clouds of crowded urban areas collected from an aerial platform. We assume that the input cloud is unordered, but it contains additional intensity and return number information which are jointly exploited by the proposed solution. Firstly, the 3-D point set is segmented into ground, vehicle, building roof, vegetation and clutter classes. Then the points with the corresponding class labels and intensity values are projected to the ground plane, where the optimal vehicle configuration is described by a Marked Point Process (MPP model of 2-D rectangles. Finally, the Multiple Birth and Death algorithm is utilized to find the configuration with the highest confidence.

  19. Comparison of Vehicle Choice Models

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, Thomas S. [Argonne National Lab. (ANL), Argonne, IL (United States); Levinson, Rebecca S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Brooker, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Liu, Changzheng [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lin, Zhenhong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Birky, Alicia [Energetics Incorporated, Columbia, MD (United States); Kontou, Eleftheria [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-10-01

    Five consumer vehicle choice models that give projections of future sales shares of light-duty vehicles were compared by running each model using the same inputs, where possible, for two scenarios. The five models compared — LVCFlex, MA3T, LAVE-Trans, ParaChoice, and ADOPT — have been used in support of the Energy Efficiency and Renewable Energy (EERE) Vehicle Technologies Office in analyses of future light-duty vehicle markets under different assumptions about future vehicle technologies and market conditions. The models give projections of sales shares by powertrain technology. Projections made using common, but not identical, inputs showed qualitative agreement, with the exception of ADOPT. ADOPT estimated somewhat lower advanced vehicle shares, mostly composed of hybrid electric vehicles. Other models projected large shares of multiple advanced vehicle powertrains. Projections of models differed in significant ways, including how different technologies penetrated cars and light trucks. Since the models are constructed differently and take different inputs, not all inputs were identical, but were the same or very similar where possible.

  20. Low Cost Mars Sample Return Utilizing Dragon Lander Project

    Science.gov (United States)

    Stoker, Carol R.

    2014-01-01

    We studied a Mars sample return (MSR) mission that lands a SpaceX Dragon Capsule on Mars carrying sample collection hardware (an arm, drill, or small rover) and a spacecraft stack consisting of a Mars Ascent Vehicle (MAV) and Earth Return Vehicle (ERV) that collectively carry the sample container from Mars back to Earth orbit.

  1. Soyuz-TM-based interim Assured Crew Return Vehicle (ACRV) for the Space Station Freedom

    Science.gov (United States)

    Semenov, Yu. P.; Babkov, Oleg I.; Timchenko, Vladimir A.; Craig, Jerry W.

    1993-01-01

    The concept of using the available Soyuz-TM Assured Crew Return Vehicle (ACRV) spacecraft for the assurance of the safety of the Space Station Freedom (SSF) crew after the departure of the Space Shuttle from SSF was proposed by the NPO Energia and was accepted by NASA in 1992. The ACRV will provide the crew with the capability to evacuate a seriously injured/ill crewmember from the SSF to a ground-based care facility under medically tolerable conditions and with the capability for a safe evacuation from SSF in the events SSF becomes uninhabitable or the Space Shuttle flights are interrupted for a time that exceeds SSF ability for crew support and/or safe operations. This paper presents the main results of studies on Phase A (including studies on the service life of ACRV; spacecraft design and operations; prelaunch processing; mission support; safety, reliability, maintenance and quality and assurance; landing, and search/rescue operations; interfaces with the SSF and with Space Shuttle; crew accommodation; motion of orbital an service modules; and ACRV injection by the Expendable Launch Vehicles), along with the objectives of further work on the Phase B.

  2. Dynamic modeling and simulation of an induction motor with adaptive backstepping design of an input-output feedback linearization controller in series hybrid electric vehicle

    Directory of Open Access Journals (Sweden)

    Jalalifar Mehran

    2007-01-01

    Full Text Available In this paper using adaptive backstepping approach an adaptive rotor flux observer which provides stator and rotor resistances estimation simultaneously for induction motor used in series hybrid electric vehicle is proposed. The controller of induction motor (IM is designed based on input-output feedback linearization technique. Combining this controller with adaptive backstepping observer the system is robust against rotor and stator resistances uncertainties. In additional, mechanical components of a hybrid electric vehicle are called from the Advanced Vehicle Simulator Software Library and then linked with the electric motor. Finally, a typical series hybrid electric vehicle is modeled and investigated. Various tests, such as acceleration traversing ramp, and fuel consumption and emission are performed on the proposed model of a series hybrid vehicle. Computer simulation results obtained, confirm the validity and performance of the proposed IM control approach using for series hybrid electric vehicle.

  3. "Can Vehicle-to-Grid Revenue Help Electric Vehicles on the Market?"

    OpenAIRE

    George R. Parsons; Michael K. Hidrue; Willett Kempton; Meryl P. Gardner

    2011-01-01

    Vehicle-to-grid (V2G) electric vehicles can return power stored in their batteries back to the power grid and be programmed to do so at times when power prices are high. Since providing this service can lead to payments to owners of vehicles, it effectively reduces the cost of electric vehicles. Using data from a national stated preference survey (n = 3029), this paper presents the first study of the potential consumer demand for V2G electric vehicles. In our choice experiment, 3029 responden...

  4. Shade tree diversity, cocoa pest damage, yield compensating inputs and farmers' net returns in West Africa.

    Directory of Open Access Journals (Sweden)

    Hervé Bertin Bisseleua Daghela

    Full Text Available Cocoa agroforests can significantly support biodiversity, yet intensification of farming practices is degrading agroforestry habitats and compromising ecosystem services such as biological pest control. Effective conservation strategies depend on the type of relationship between agricultural matrix, biodiversity and ecosystem services, but to date the shape of this relationship is unknown. We linked shade index calculated from eight vegetation variables, with insect pests and beneficial insects (ants, wasps and spiders in 20 cocoa agroforests differing in woody and herbaceous vegetation diversity. We measured herbivory and predatory rates, and quantified resulting increases in cocoa yield and net returns. We found that number of spider webs and wasp nests significantly decreased with increasing density of exotic shade tree species. Greater species richness of native shade tree species was associated with a higher number of wasp nests and spider webs while species richness of understory plants did not have a strong impact on these beneficial species. Species richness of ants, wasp nests and spider webs peaked at higher levels of plant species richness. The number of herbivore species (mirid bugs and cocoa pod borers and the rate of herbivory on cocoa pods decreased with increasing shade index. Shade index was negatively related to yield, with yield significantly higher at shade and herb covers<50%. However, higher inputs in the cocoa farms do not necessarily result in a higher net return. In conclusion, our study shows the importance of a diverse shade canopy in reducing damage caused by cocoa pests. It also highlights the importance of conservation initiatives in tropical agroforestry landscapes.

  5. Comparison of Vehicle Choice Models

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, Thomas S. [Argonne National Lab. (ANL), Argonne, IL (United States); Levinson, Rebecca S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Brooker, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Liu, Changzheng [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lin, Zhenhong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Birky, Alicia [Energetics Incorporated, Columbia, MD (United States); Kontou, Eleftheria [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-10-31

    Five consumer vehicle choice models that give projections of future sales shares of light-duty vehicles were compared by running each model using the same inputs, where possible, for two scenarios. The five models compared — LVCFlex, MA3T, LAVE-Trans, ParaChoice, and ADOPT — have been used in support of the Energy Efficiency and Renewable Energy (EERE) Vehicle Technologies Office in analyses of future light-duty vehicle markets under different assumptions about future vehicle technologies and market conditions. The models give projections of sales shares by powertrain technology. Projections made using common, but not identical, inputs showed qualitative agreement, with the exception of ADOPT. ADOPT estimated somewhat lower advanced vehicle shares, mostly composed of hybrid electric vehicles. Other models projected large shares of multiple advanced vehicle powertrains. Projections of models differed in significant ways, including how different technologies penetrated cars and light trucks. Since the models are constructed differently and take different inputs, not all inputs were identical, but were the same or very similar where possible. Projections by all models were in close agreement only in the first few years. Although the projections from LVCFlex, MA3T, LAVE-Trans, and ParaChoice were in qualitative agreement, there were significant differences in sales shares given by the different models for individual powertrain types, particularly in later years (2030 and later). For example, projected sales shares of conventional spark-ignition vehicles in 2030 for a given scenario ranged from 35% to 74%. Reasons for such differences are discussed, recognizing that these models were not developed to give quantitatively accurate predictions of future sales shares, but to represent vehicles markets realistically and capture the connections between sales and important influences. Model features were also compared at a high level, and suggestions for further comparison

  6. Mars Sample Return Using Solar Sail Propulsion

    Science.gov (United States)

    Johnson, Les; Macdonald, Malcolm; Mcinnes, Colin; Percy, Tom

    2012-01-01

    Many Mars Sample Return (MSR) architecture studies have been conducted over the years. A key element of them is the Earth Return Stage (ERS) whose objective is to obtain the sample from the Mars Ascent Vehicle (MAV) and return it safely to the surface of the Earth. ERS designs predominantly use chemical propulsion [1], incurring a significant launch mass penalty due to the low specific impulse of such systems coupled with the launch mass sensitivity to returned mass. It is proposed to use solar sail propulsion for the ERS, providing a high (effective) specific impulse propulsion system in the final stage of the multi-stage system. By doing so to the launch mass of the orbiter mission can be significantly reduced and hence potentially decreasing mission cost. Further, solar sailing offers a unique set of non-Keplerian low thrust trajectories that may enable modifications to the current approach to designing the Earth Entry Vehicle by potentially reducing the Earth arrival velocity. This modification will further decrease the mass of the orbiter system. Solar sail propulsion uses sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like surface made of a lightweight, reflective material. The continuous photonic pressure provides propellantless thrust to conduct orbital maneuvering and plane changes more efficiently than conventional chemical propulsion. Because the Sun supplies the necessary propulsive energy, solar sails require no onboard propellant, thus reducing system mass. This technology is currently at TRL 7/8 as demonstrated by the 2010 flight of the Japanese Aerospace Exploration Agency, JAXA, IKAROS mission. [2

  7. Navigation of the autonomous vehicle reverse movement

    Science.gov (United States)

    Rachkov, M.; Petukhov, S.

    2018-02-01

    The paper presents a mathematical formulation of the vehicle reverse motion along a multi-link polygonal trajectory consisting of rectilinear segments interconnected by nodal points. Relevance of the problem is caused by the need to solve a number of tasks: to save the vehicle in the event of а communication break by returning along the trajectory already passed, to avoid a turn on the ground in constrained obstacles or dangerous conditions, or a partial return stroke for the subsequent bypass of the obstacle and continuation of the forward movement. The method of navigation with direct movement assumes that the reverse path is elaborated by using landmarks. To measure landmarks on board, a block of cameras is placed on a vehicle controlled by the operator through the radio channel. Errors in estimating deviation from the nominal trajectory of motion are determined using the multidimensional correlation analysis apparatus based on the dynamics of a lateral deviation error and a vehicle speed error. The result of the experiment showed a relatively high accuracy in determining the state vector that provides the vehicle reverse motion relative to the reference trajectory with a practically acceptable error while returning to the start point.

  8. Market penetration scenarios for fuel cell vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, C.E.; James, B.D.; Lomax, F.D. Jr. [Directed Technologies, Inc., Arlington, VA (United States)

    1997-12-31

    Fuel cell vehicles may create the first mass market for hydrogen as an energy carrier. Directed Technologies, Inc., working with the US Department of Energy hydrogen systems analysis team, has developed a time-dependent computer market penetration model. This model estimates the number of fuel cell vehicles that would be purchased over time as a function of their cost and the cost of hydrogen relative to the costs of competing vehicles and fuels. The model then calculates the return on investment for fuel cell vehicle manufacturers and hydrogen fuel suppliers. The model also projects the benefit/cost ratio for government--the ratio of societal benefits such as reduced oil consumption, reduced urban air pollution and reduced greenhouse gas emissions to the government cost for assisting the development of hydrogen energy and fuel cell vehicle technologies. The purpose of this model is to assist industry and government in choosing the best investment strategies to achieve significant return on investment and to maximize benefit/cost ratios. The model can illustrate trends and highlight the sensitivity of market penetration to various parameters such as fuel cell efficiency, cost, weight, and hydrogen cost. It can also illustrate the potential benefits of successful R and D and early demonstration projects. Results will be shown comparing the market penetration and return on investment estimates for direct hydrogen fuel cell vehicles compared to fuel cell vehicles with onboard fuel processors including methanol steam reformers and gasoline partial oxidation systems. Other alternative fueled vehicles including natural gas hybrids, direct injection diesels and hydrogen-powered internal combustion hybrid vehicles will also be analyzed.

  9. Lunar lander and return propulsion system trade study

    Science.gov (United States)

    Hurlbert, Eric A.; Moreland, Robert; Sanders, Gerald B.; Robertson, Edward A.; Amidei, David; Mulholland, John

    1993-01-01

    This trade study was initiated at NASA/JSC in May 1992 to develop and evaluate main propulsion system alternatives to the reference First Lunar Outpost (FLO) lander and return-stage transportation system concept. Thirteen alternative configurations were developed to explore the impacts of various combinations of return stage propellants, using either pressure or pump-fed propulsion systems and various staging options. Besides two-stage vehicle concepts, the merits of single-stage and stage-and-a-half options were also assessed in combination with high-performance liquid oxygen and liquid hydrogen propellants. Configurations using an integrated modular cryogenic engine were developed to assess potential improvements in packaging efficiency, mass performance, and system reliability compared to non-modular cryogenic designs. The selection process to evaluate the various designs was the analytic hierarchy process. The trade study showed that a pressure-fed MMH/N2O4 return stage and RL10-based lander stage is the best option for a 1999 launch. While results of this study are tailored to FLO needs, the design date, criteria, and selection methodology are applicable to the design of other crewed lunar landing and return vehicles.

  10. Mars Sample Return - Launch and Detection Strategies for Orbital Rendezvous

    Science.gov (United States)

    Woolley, Ryan C.; Mattingly, Richard L.; Riedel, Joseph E.; Sturm, Erick J.

    2011-01-01

    This study sets forth conceptual mission design strategies for the ascent and rendezvous phase of the proposed NASA/ESA joint Mars Sample Return Campaign. The current notional mission architecture calls for the launch of an acquisition/cache rover in 2018, an orbiter with an Earth return vehicle in 2022, and a fetch rover and ascent vehicle in 2024. Strategies are presented to launch the sample into a coplanar orbit with the Orbiter which facilitate robust optical detection, orbit determination, and rendezvous. Repeating ground track orbits exist at 457 and 572 km which provide multiple launch opportunities with similar geometries for detection and rendezvous.

  11. Measurement and Comparison of Variance in the Performance of Algerian Universities using models of Returns to Scale Approach

    Directory of Open Access Journals (Sweden)

    Imane Bebba

    2017-08-01

    Full Text Available This study aimed to measure and compare the performance of forty-seven Algerian universities, using models of returns to Scale approach, which is based primarily on the Data Envelopment Analysis  method. In order to achieve the objective of the study, a set of variables was chosen to represent the dimension of teaching. The variables consisted of three input variables, which were:  the total number of students  in the undergraduate level, students in the post graduate level and the number of permanent professors. On the other hand, the output variable was represented by the total number of students holding degrees of the two levels. Four basic models for data envelopment analysis method were applied. These were: (Scale Returns, represented by input-oriented and output-oriented constant returns and input-oriented and output-oriented  variable returns. After the analysis of data, results revealed that eight universities achieved full efficiency according to constant returns to scale in both input and output orientations. Seventeen universities achieved full efficiency according to the model of input-oriented returns to scale variable. Sixteen universities achieved full efficiency according to the model of output-oriented  returns to scale variable. Therefore, during the performance measurement, the size of the university, competition, financial and infrastructure constraints, and the process of resource allocation within the university  should be taken into consideration. Also, multiple input and output variables reflecting the dimensions of teaching, research, and community service should be included while measuring and assessing the performance of Algerian universities, rather than using two variables which do not reflect the actual performance of these universities. Keywords: Performance of Algerian Universities, Data envelopment analysis method , Constant returns to scale, Variable returns to scale, Input-orientation, Output-orientation.

  12. Modular Robotic Vehicle

    Science.gov (United States)

    Borroni-Bird, Christopher E. (Inventor); Vitale, Robert L. (Inventor); Lee, Chunhao J. (Inventor); Ambrose, Robert O. (Inventor); Bluethmann, William J. (Inventor); Junkin, Lucien Q. (Inventor); Lutz, Jonathan J. (Inventor); Guo, Raymond (Inventor); Lapp, Anthony Joseph (Inventor); Ridley, Justin S. (Inventor)

    2015-01-01

    A modular robotic vehicle includes a chassis, driver input devices, an energy storage system (ESS), a power electronics module (PEM), modular electronic assemblies (eModules) connected to the ESS via the PEM, one or more master controllers, and various embedded controllers. Each eModule includes a drive wheel containing a propulsion-braking module, and a housing containing propulsion and braking control assemblies with respective embedded propulsion and brake controllers, and a mounting bracket covering a steering control assembly with embedded steering controllers. The master controller, which is in communication with each eModule and with the driver input devices, communicates with and independently controls each eModule, by-wire, via the embedded controllers to establish a desired operating mode. Modes may include a two-wheel, four-wheel, diamond, and omni-directional steering modes as well as a park mode. A bumper may enable docking with another vehicle, with shared control over the eModules of the vehicles.

  13. Sustainable Mars Sample Return

    Science.gov (United States)

    Alston, Christie; Hancock, Sean; Laub, Joshua; Perry, Christopher; Ash, Robert

    2011-01-01

    The proposed Mars sample return mission will be completed using natural Martian resources for the majority of its operations. The system uses the following technologies: In-Situ Propellant Production (ISPP), a methane-oxygen propelled Mars Ascent Vehicle (MAV), a carbon dioxide powered hopper, and a hydrogen fueled balloon system (large balloons and small weather balloons). The ISPP system will produce the hydrogen, methane, and oxygen using a Sabatier reactor. a water electrolysis cell, water extracted from the Martian surface, and carbon dioxide extracted from the Martian atmosphere. Indigenous hydrogen will fuel the balloon systems and locally-derived methane and oxygen will fuel the MAV for the return of a 50 kg sample to Earth. The ISPP system will have a production cycle of 800 days and the estimated overall mission length is 1355 days from Earth departure to return to low Earth orbit. Combining these advanced technologies will enable the proposed sample return mission to be executed with reduced initial launch mass and thus be more cost efficient. The successful completion of this mission will serve as the next step in the advancement of Mars exploration technology.

  14. Decentralized fuzzy control of multiple nonholonomic vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Driessen, B.J.; Feddema, J.T.; Kwok, K.S.

    1997-09-01

    This work considers the problem of controlling multiple nonholonomic vehicles so that they converge to a scent source without colliding with each other. Since the control is to be implemented on simple 8-bit microcontrollers, fuzzy control rules are used to simplify a linear quadratic regulator control design. The inputs to the fuzzy controllers for each vehicle are the (noisy) direction to the source, the distance to the closest neighbor vehicle, and the direction to the closest vehicle. These directions are discretized into four values: Forward, Behind, Left, and Right, and the distance into three values: Near, Far, Gone. The values of the control at these discrete values are obtained based on the collision-avoidance repulsive forces and the change of variables that reduces the motion control problem of each nonholonomic vehicle to a nonsingular one with two degrees of freedom, instead of three. A fuzzy inference system is used to obtain control values for inputs between the small number of discrete input values. Simulation results are provided which demonstrate that the fuzzy control law performs well compared to the exact controller. In fact, the fuzzy controller demonstrates improved robustness to noise.

  15. Technical and Feasibility Analysis of Gasoline and Natural Gas Fuelled Vehicles

    Directory of Open Access Journals (Sweden)

    Charalambos Chasos

    2014-03-01

    Full Text Available There is recent interest for the utilisation of natural gas for empowering the internal combustion engines (ICE of vehicles. The production of novel natural gas ICE for vehicles, as well as the conversion of existing gasoline fuelled ICE of vehicles to natural gas fuelled ICE are new technologies which require to be analysed and assessed. The objective of the present study is to examine the adaptation of natural gas as vehicle fuel and carry out a technical analysis and an economical feasibility analysis of the two types of ICE vehicles, namely gasoline and natural gas fuelled vehicles. The technical model uses the physical properties of the two fuels and the performance factors of internal combustion engines including brake thermal efficiency. The resulting exhaust gas emissions are also estimated by the technical model using combustion calculations which provide the expected levels of exhaust gas emissions. Based on the analysis with the technical model, comparisons of the two types of engines are performed. Furthermore, the estimated performance characteristics of the two types of engines, along with local statistical data on annual fuel imports and annual fuel consumption for transportation and data on the vehicles fleet for the case study of Cyprus are used as input in the economical model. For the base year 2013, data of natural gas price is also used in the economical model. The economical model estimates the capital cost, the carbon dioxide emissions avoidance of fines, the net present value and the internal rate of return of the investment of large scale adaptation of natural gas fuelled vehicles for the case study. From the results and comparisons, conclusions are drawn and recommendations are provided for the adaptation of natural gas vehicles which can provide improved performance with reduced pollutant emissions.

  16. MIFT: GIFT Combinatorial Geometry Input to VCS Code

    Science.gov (United States)

    1977-03-01

    r-w w-^ H ^ß0318is CQ BRL °RCUMr REPORT NO. 1967 —-S: ... MIFT: GIFT COMBINATORIAL GEOMETRY INPUT TO VCS CODE Albert E...TITLE (and Subtitle) MIFT: GIFT Combinatorial Geometry Input to VCS Code S. TYPE OF REPORT & PERIOD COVERED FINAL 6. PERFORMING ORG. REPORT NUMBER...Vehicle Code System (VCS) called MORSE was modified to accept the GIFT combinatorial geometry package. GIFT , as opposed to the geometry package

  17. The impacts of regulation via the allowed rate of return constraint on social welfare, input choices, and level of output in the privately-owned electric utilities in the United States

    International Nuclear Information System (INIS)

    Phongam, S.

    1990-01-01

    This study analyzes the effect of change in price elasticity of demand for electricity on social welfare, allowed rate of return, and marginal revenue product of each input used to produce electricity. Price elasticities of demand for electricity in residential, commercial, and industrial sectors are compared as well as total demand in 1987. Also compared are these price elasticities between 1982 and 1987. Several conclusions are: (1) There is an overcapitalization in privately-owned electric utilities because at the chosen level of output, marginal revenue product of capital is less than its price. (2) Elastic demand for electricity will improve values of social welfare and marginal revenue product of inputs. (3) Tightening allowed rate of return will increase the amount of capital and labor usages, but decrease fuel, output, and social welfare. (4) Both residential and industrial demand for electricity are elastic, but commercial demand is inelastic. (5) By making comparison of price elasticity of demand between 1982 and 1987, it shows that price elasticity of demand for electricity in residential, industrial, and total demand are increasing. However, for the commercial sector, the price elasticity is decreasing somewhat

  18. Thermal Protection for Mars Sample Return Earth Entry Vehicle: A Grand Challenge for Design Methodology and Reliability Verification

    Science.gov (United States)

    Venkatapathy, Ethiraj; Gage, Peter; Wright, Michael J.

    2017-01-01

    Mars Sample Return is our Grand Challenge for the coming decade. TPS (Thermal Protection System) nominal performance is not the key challenge. The main difficulty for designers is the need to verify unprecedented reliability for the entry system: current guidelines for prevention of backward contamination require that the probability of spores larger than 1 micron diameter escaping into the Earth environment be lower than 1 million for the entire system, and the allocation to TPS would be more stringent than that. For reference, the reliability allocation for Orion TPS is closer to 11000, and the demonstrated reliability for previous human Earth return systems was closer to 1100. Improving reliability by more than 3 orders of magnitude is a grand challenge indeed. The TPS community must embrace the possibility of new architectures that are focused on reliability above thermal performance and mass efficiency. MSR (Mars Sample Return) EEV (Earth Entry Vehicle) will be hit with MMOD (Micrometeoroid and Orbital Debris) prior to reentry. A chute-less aero-shell design which allows for self-righting shape was baselined in prior MSR studies, with the assumption that a passive system will maximize EEV robustness. Hence the aero-shell along with the TPS has to take ground impact and not break apart. System verification will require testing to establish ablative performance and thermal failure but also testing of damage from MMOD, and structural performance at ground impact. Mission requirements will demand analysis, testing and verification that are focused on establishing reliability of the design. In this proposed talk, we will focus on the grand challenge of MSR EEV TPS and the need for innovative approaches to address challenges in modeling, testing, manufacturing and verification.

  19. Computer Generated Inputs for NMIS Processor Verification

    International Nuclear Information System (INIS)

    J. A. Mullens; J. E. Breeding; J. A. McEvers; R. W. Wysor; L. G. Chiang; J. R. Lenarduzzi; J. T. Mihalczo; J. K. Mattingly

    2001-01-01

    Proper operation of the Nuclear Identification Materials System (NMIS) processor can be verified using computer-generated inputs [BIST (Built-In-Self-Test)] at the digital inputs. Preselected sequences of input pulses to all channels with known correlation functions are compared to the output of the processor. These types of verifications have been utilized in NMIS type correlation processors at the Oak Ridge National Laboratory since 1984. The use of this test confirmed a malfunction in a NMIS processor at the All-Russian Scientific Research Institute of Experimental Physics (VNIIEF) in 1998. The NMIS processor boards were returned to the U.S. for repair and subsequently used in NMIS passive and active measurements with Pu at VNIIEF in 1999

  20. COMPASS Final Report: Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER)

    Science.gov (United States)

    Oleson, Steven R.; McGuire, Melissa L.

    2009-01-01

    In this study, the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team completed a design for a multi-asteroid (Nereus and 1996 FG3) sample return capable spacecraft for the NASA In-Space Propulsion Office. The objective of the study was to support technology development and assess the relative benefits of different electric propulsion systems on asteroid sample return design. The design uses a single, heritage Orion solar array (SA) (approx.6.5 kW at 1 AU) to power a single NASA Evolutionary Xenon Thruster ((NEXT) a spare NEXT is carried) to propel a lander to two near Earth asteroids. After landing and gathering science samples, the Solar Electric Propulsion (SEP) vehicle spirals back to Earth where it drops off the first sample s return capsule and performs an Earth flyby to assist the craft in rendezvousing with a second asteroid, which is then sampled. The second sample is returned in a similar fashion. The vehicle, dubbed Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER), easily fits in an Atlas 401 launcher and its cost estimates put the mission in the New Frontier s (NF's) class mission.

  1. Robust input design for nonlinear dynamic modeling of AUV.

    Science.gov (United States)

    Nouri, Nowrouz Mohammad; Valadi, Mehrdad

    2017-09-01

    Input design has a dominant role in developing the dynamic model of autonomous underwater vehicles (AUVs) through system identification. Optimal input design is the process of generating informative inputs that can be used to generate the good quality dynamic model of AUVs. In a problem with optimal input design, the desired input signal depends on the unknown system which is intended to be identified. In this paper, the input design approach which is robust to uncertainties in model parameters is used. The Bayesian robust design strategy is applied to design input signals for dynamic modeling of AUVs. The employed approach can design multiple inputs and apply constraints on an AUV system's inputs and outputs. Particle swarm optimization (PSO) is employed to solve the constraint robust optimization problem. The presented algorithm is used for designing the input signals for an AUV, and the estimate obtained by robust input design is compared with that of the optimal input design. According to the results, proposed input design can satisfy both robustness of constraints and optimality. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  2. 77 FR 12355 - Enabling a Secure Environment for Vehicle-to-Vehicle and Vehicle-to-Infrastructure Transactions...

    Science.gov (United States)

    2012-02-29

    ... provide input into research being conducted on potential organizational and business models for supporting... business models for supporting such a network, to attract users and revenue to finance such a system? What... approach to security involving the exchange of digital certificates among legitimate trusted vehicles and...

  3. Infrastructure-Based Sensors Augmenting Efficient Autonomous Vehicle Operations: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Myungsoo [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Markel, Anthony J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-15

    Autonomous vehicle technology development relies on an on-board network of fused sensor inputs for safe and efficient operation. The fused sensors offer multiple perspectives of similar information aiding in system decision robustness. The high cost of full systems on individual vehicles is seen as a potential barrier to broad adoption and achieving system energy efficiency gains. Since traffic in autonomous vehicle technology development relies on an on-board network of fused sensor inputs for safe and efficient operation. The fused sensors offer multiple perspectives of similar information aiding in system decision robustness. The high cost of full systems on individual vehicles is seen as a potential barrier to broad adoption and achieving system energy efficiency gains.

  4. Heavy Duty Vehicle Futures Analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Askin, Amanda Christine; Barter, Garrett.; West, Todd H.; Manley, Dawn Kataoka

    2014-05-01

    This report describes work performed for an Early Career Research and Development project. This project developed a heavy-duty vehicle (HDV) sector model to assess the factors influencing alternative fuel and efficiency technology adoption. This model builds on a Sandia light duty vehicle sector model and provides a platform for assessing potential impacts of technological advancements developed at the Combustion Research Facility. Alternative fuel and technology adoption modeling is typically developed around a small set of scenarios. This HDV sector model segments the HDV sector and parameterizes input values, such as fuel prices, efficiencies, and vehicle costs. This parameterization enables sensitivity and trade space analyses to identify the inputs that are most associated with outputs of interest, such as diesel consumption and greenhouse gas emissions. Thus this analysis tool enables identification of the most significant HDV sector drivers that can be used to support energy security and climate change goals.

  5. Predicting vehicle fuel consumption patterns using floating vehicle data.

    Science.gov (United States)

    Du, Yiman; Wu, Jianping; Yang, Senyan; Zhou, Liutong

    2017-09-01

    The status of energy consumption and air pollution in China is serious. It is important to analyze and predict the different fuel consumption of various types of vehicles under different influence factors. In order to fully describe the relationship between fuel consumption and the impact factors, massive amounts of floating vehicle data were used. The fuel consumption pattern and congestion pattern based on large samples of historical floating vehicle data were explored, drivers' information and vehicles' parameters from different group classification were probed, and the average velocity and average fuel consumption in the temporal dimension and spatial dimension were analyzed respectively. The fuel consumption forecasting model was established by using a Back Propagation Neural Network. Part of the sample set was used to train the forecasting model and the remaining part of the sample set was used as input to the forecasting model. Copyright © 2017. Published by Elsevier B.V.

  6. Autonomous Navigation Apparatus With Neural Network for a Mobile Vehicle

    Science.gov (United States)

    Quraishi, Naveed (Inventor)

    1996-01-01

    An autonomous navigation system for a mobile vehicle arranged to move within an environment includes a plurality of sensors arranged on the vehicle and at least one neural network including an input layer coupled to the sensors, a hidden layer coupled to the input layer, and an output layer coupled to the hidden layer. The neural network produces output signals representing respective positions of the vehicle, such as the X coordinate, the Y coordinate, and the angular orientation of the vehicle. A plurality of patch locations within the environment are used to train the neural networks to produce the correct outputs in response to the distances sensed.

  7. Method of Controlling Steering of a Ground Vehicle

    Science.gov (United States)

    Dawson, Andrew D. (Inventor); Bluethmann, William J. (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Guo, Raymond (Inventor); Atluri, Venkata Prasad (Inventor)

    2016-01-01

    A method of controlling steering of a vehicle through setting wheel angles of a plurality of modular electronic corner assemblies (eModules) is provided. The method includes receiving a driving mode selected from a mode selection menu. A position of a steering input device is determined in a master controller. A velocity of the vehicle is determined, in the master controller, when the determined position of the steering input device is near center. A drive mode request corresponding to the selected driving mode to the plurality of steering controllers is transmitted to the master controller. A required steering angle of each of the plurality of eModules is determined, in the master controller, as a function of the determined position of the steering input device, the determined velocity of the vehicle, and the selected first driving mode. The eModules are set to the respective determined steering angles.

  8. Phobos Sample Return: Next Approach

    Science.gov (United States)

    Zelenyi, Lev; Martynov, Maxim; Zakharov, Alexander; Korablev, Oleg; Ivanov, Alexey; Karabadzak, George

    possible scenario of the Boomerang mission includes the approach to Deimos prior to the landing of Phobos. The needed excess ΔV w.r.t. simple scenario (elliptical orbit à near-Phobos orbit) amounts to 0.67 km s-1 (1.6 vs 0.93 km s-1). The Boomerang mission basically repeats the Phobos-SR (2011) architecture, where the transfer-orbiting spacecraft lands on the Phobos surface and a small return vehicle launches the return capsule to Earth. We consider the Boomerang mission as an important step in Mars exploration and a direct precursor of Mars Sample Return. The following elements of the Boomerang mission might be directly employed, or serve as the prototypes for the Mars Sample return in future: Return vehicle, Earth descent module, Transfer-orbital spacecraft. We urge the development of this project for its high science value and recognize its elements as potential national contribution to an international Mars Sample Return project. Galimov E.M., Phobos sample return mission: scientific substantiation, Solar System Res., v.44, No.1, pp5-14, 2010. Chappaz L., H.J. Melosh, M. Vaguero, and K.C. Howell, Material transfer from the surface of Mars to Phobos and Deimos, 43rd Lunar and planetary Science Conference, paper 1422, 2012.

  9. State, Parameter, and Unknown Input Estimation Problems in Active Automotive Safety Applications

    Science.gov (United States)

    Phanomchoeng, Gridsada

    A variety of driver assistance systems such as traction control, electronic stability control (ESC), rollover prevention and lane departure avoidance systems are being developed by automotive manufacturers to reduce driver burden, partially automate normal driving operations, and reduce accidents. The effectiveness of these driver assistance systems can be significant enhanced if the real-time values of several vehicle parameters and state variables, namely tire-road friction coefficient, slip angle, roll angle, and rollover index, can be known. Since there are no inexpensive sensors available to measure these variables, it is necessary to estimate them. However, due to the significant nonlinear dynamics in a vehicle, due to unknown and changing plant parameters, and due to the presence of unknown input disturbances, the design of estimation algorithms for this application is challenging. This dissertation develops a new approach to observer design for nonlinear systems in which the nonlinearity has a globally (or locally) bounded Jacobian. The developed approach utilizes a modified version of the mean value theorem to express the nonlinearity in the estimation error dynamics as a convex combination of known matrices with time varying coefficients. The observer gains are then obtained by solving linear matrix inequalities (LMIs). A number of illustrative examples are presented to show that the developed approach is less conservative and more useful than the standard Lipschitz assumption based nonlinear observer. The developed nonlinear observer is utilized for estimation of slip angle, longitudinal vehicle velocity, and vehicle roll angle. In order to predict and prevent vehicle rollovers in tripped situations, it is necessary to estimate the vertical tire forces in the presence of unknown road disturbance inputs. An approach to estimate unknown disturbance inputs in nonlinear systems using dynamic model inversion and a modified version of the mean value theorem is

  10. Fluctuation behaviors of financial return volatility duration

    Science.gov (United States)

    Niu, Hongli; Wang, Jun; Lu, Yunfan

    2016-04-01

    It is of significantly crucial to understand the return volatility of financial markets because it helps to quantify the investment risk, optimize the portfolio, and provide a key input of option pricing models. The characteristics of isolated high volatility events above certain threshold in price fluctuations and the distributions of return intervals between these events arouse great interest in financial research. In the present work, we introduce a new concept of daily return volatility duration, which is defined as the shortest passage time when the future volatility intensity is above or below the current volatility intensity (without predefining a threshold). The statistical properties of the daily return volatility durations for seven representative stock indices from the world financial markets are investigated. Some useful and interesting empirical results of these volatility duration series about the probability distributions, memory effects and multifractal properties are obtained. These results also show that the proposed stock volatility series analysis is a meaningful and beneficial trial.

  11. A NEW EMPIRICAL INVESTIGATION OF THE PLATINUM SPOT RETURNS

    Directory of Open Access Journals (Sweden)

    Simone Kruse

    2017-08-01

    Full Text Available The global platinum market has been in downturn and unstable for five consecutive years, and thus market participants are demanding effective quantitative risk management tools. Since platinum is so widely used and serves as an important investment vehicle, the importance of risk management of platinum spot returns cannot be understated. In this paper, we take advantage of a very popular econometric model, the generalized autoregressive conditional heteroscedasticity (GARCH model, for platinum returns. We received two important findings by using the conventional GARCH models in explain daily platinum spot returns. First, it is crucial to introduce heavy-tailed distribution to explain conditional heavy tails; and second, the NRIG distribution performs better than the most widely-used heavy-tailed distribution, the Student’s t distribution.

  12. Real-time identification of vehicle motion-modes using neural networks

    Science.gov (United States)

    Wang, Lifu; Zhang, Nong; Du, Haiping

    2015-01-01

    A four-wheel ground vehicle has three body-dominated motion-modes, that is, bounce, roll, and pitch motion-modes. Real-time identification of these motion-modes can make vehicle suspensions, in particular, active suspensions, target on the dominant motion-mode and apply appropriate control strategies to improve its performance with less power consumption. Recently, a motion-mode energy method (MEM) was developed to identify the vehicle body motion-modes. However, this method requires the measurement of full vehicle states and road inputs, which are not always available in practice. This paper proposes an alternative approach to identify vehicle primary motion-modes with acceptable accuracy by employing neural networks (NNs). The effectiveness of the trained NNs is verified on a 10-DOF full-car model under various types of excitation inputs. The results confirm that the proposed method is effective in determining vehicle primary motion-modes with comparable accuracy to the MEM method. Experimental data is further used to validate the proposed method.

  13. Design of LQG Controller for Active Suspension without Considering Road Input Signals

    Directory of Open Access Journals (Sweden)

    Hui Pang

    2017-01-01

    Full Text Available As the road conditions are completely unknown in the design of a suspension controller, an improved linear quadratic and Gaussian distributed (LQG controller is proposed for active suspension system without considering road input signals. The main purpose is to optimize the vehicle body acceleration, pitching angular acceleration, displacement of suspension system, and tire dynamic deflection comprehensively. Meanwhile, it will extend the applicability of the LQG controller. Firstly, the half-vehicle and road input mathematical models of an active suspension system are established, with the weight coefficients of each evaluating indicator optimized by using genetic algorithm (GA. Then, a simulation model is built in Matlab/Simulink environment. Finally, a comparison of simulation is conducted to illustrate that the proposed LQG controller can obtain the better comprehensive performance of vehicle suspension system and improve riding comfort and handling safety compared to the conventional one.

  14. Coupled radiative gasdynamic interaction and non-equilibrium dissociation for large-scale returned space vehicles

    International Nuclear Information System (INIS)

    Surzhikov, S.

    2012-01-01

    Graphical abstract: It has been shown that different coupled vibrational dissociation models, being applied for solving coupled radiative gasdynamic problems for large size space vehicles, exert noticeable effect on radiative heating of its surface at orbital entry on high altitudes (h ⩾ 70 km). This influence decreases with decreasing the space vehicles sizes. Figure shows translational (solid lines) and vibrational (dashed lines) temperatures in shock layer with (circle markers) and without (triangles markers) radiative-gasdynamic interaction for one trajectory point of entering space vehicle. Highlights: ► Nonequilibrium dissociation processes exert effect on radiation heating of space vehicles (SV). ► The radiation gas dynamic interaction enhances this influence. ► This influence increases with increasing the SV sizes. - Abstract: Radiative aerothermodynamics of large-scale space vehicles is considered for Earth orbital entry at zero angle of attack. Brief description of used radiative gasdynamic model of physically and chemically nonequilibrium, viscous, heat conductive and radiative gas of complex chemical composition is presented. Radiation gasdynamic (RadGD) interaction in high temperature shock layer is studied by means of numerical experiment. It is shown that radiation–gasdynamic coupling for orbital space vehicles of large size is important for high altitude part of entering trajectory. It is demonstrated that the use of different models of coupled vibrational dissociation (CVD) in conditions of RadGD interaction gives rise temperature variation in shock layer and, as a result, leads to significant variation of radiative heating of space vehicle.

  15. International Space Station Crew Return Vehicle: X-38. Educational Brief.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    The International Space Station (ISS) will provide the world with an orbiting laboratory that will have long-duration micro-gravity experimentation capability. The crew size for this facility will depend upon the crew return capability. The first crews will consist of three astronauts from Russia and the United States. The crew is limited to three…

  16. Autonomous Laser-Powered Vehicle

    Science.gov (United States)

    Stone, William C. (Inventor); Hogan, Bartholomew P. (Inventor)

    2017-01-01

    An autonomous laser-powered vehicle designed to autonomously penetrate through ice caps of substantial (e.g., kilometers) thickness by melting a path ahead of the vehicle as it descends. A high powered laser beam is transmitted to the vehicle via an onboard bare fiber spooler. After the beam enters through the dispersion optics, the beam expands into a cavity. A radiation shield limits backscatter radiation from heating the optics. The expanded beam enters the heat exchanger and is reflected by a dispersion mirror. Forward-facing beveled circular grooves absorb the reflected radiant energy preventing the energy from being reflected back towards the optics. Microchannels along the inner circumference of the beam dump heat exchanger maximize heat transfer. Sufficient amount of fiber is wound on the fiber spooler to permit not only a descent but also to permit a sample return mission by inverting the vehicle and melting its way back to the surface.

  17. 19 CFR 148.32 - Vehicles, aircraft, boats, teams and saddle horses taken abroad.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Vehicles, aircraft, boats, teams and saddle horses... for Returning Residents § 148.32 Vehicles, aircraft, boats, teams and saddle horses taken abroad. (a) Admission free of duty. Automobiles and other vehicles, aircraft, boats, teams and saddle horses, together...

  18. Advanced technology mobile robotics vehicle fleet

    International Nuclear Information System (INIS)

    McGovern, D.E.

    1987-03-01

    A fleet of vehicles is being developed and maintained by Sandia National Laboratories for studies in remote control and autonomous operation. The vehicles range from modified commercial vehicles to specially constructed mobile platforms and are utilized as testbeds for developing concepts in the areas of remote control (teleoperation) and computer control (autonomy). Actuators control the vehicle speed, brakes, and steering via manual input from a remote driving station or through some level of digital computer control. On-board processing may include simple vehicle control functions or may allow for unmanned, autonomous operation. Communication links are provided for digital communication between control computers, television transmission for vehicle vision, and voice for local control. SNL can develop, test, and evaluate sensors, processing requirements, various methods of actuator implementation, operator controlled feedback requirements, and vehicle operations. A description of the major features and uses for each of the vehicles in the fleet is provided

  19. X-38 vehicle #131R arrives at NASA Dryden via NASA'S Super Guppy transport aircraft

    Science.gov (United States)

    2000-01-01

    NASA's Super Guppy transport aircraft landed at Edwards Air Force Base, Calif. on July 11, 2000, to deliver the latest version of the X-38 drop vehicle to Dryden. The X-38s are intended as prototypes for a possible 'crew lifeboat' for the International Space Station. The X-38 vehicle 131R will demonstrate a huge 7,500 square-foot parafoil that will that will enable the potential crew return vehicle to land on the length of a football field after returning from space. The crew return vehicle is intended to serve as a possible emergency transport to carry a crew to safety in the event of problems with the International Space Station. The Super Guppy evolved from the 1960s-vintage Pregnant Guppy, used for transporting outsized sections of the Apollo moon rocket. The Super Guppy was modified from 1950s-vintage Boeing C-97. NASA acquired its Super Guppy from the European Space Agency in 1997.

  20. Mobile robot vehicles for physical security

    International Nuclear Information System (INIS)

    McGovern, D.E.

    1987-07-01

    A fleet of vehicles is being developed and maintained by Sandia National Labs for studies in remote control and autonomous operation. These vehicles range from modified commercial vehicles to specially constructed mobile platforms and are utilized as test beds for developing concepts in the application of robotics to interior and exterior physical security. Actuators control the vehicle speed, brakes, and steering through manual input from a remote driving station or through some level of digital computer control. On-board processing may include simple vehicle control functions or may allow for unmanned, autonomous operation. communication links are provided for digital communication between control computers, television transmission for vehicle vision, and voice for local control. With these vehicles, SNL can develop, test, and evaluate sensors, processing requirements, various methods of actuator implementation, operator controlled feedback requirements, and vehicle operations. A description of the major features and uses for each of the vehicles in the fleet is provided

  1. Mobile robot vehicles for physical security

    International Nuclear Information System (INIS)

    Mc Govern, D.E.

    1987-01-01

    A fleet of vehicles is being developed and maintained by Sandia National Labs for studies in remote control and autonomous operation. These vehicles range from modified commercial vehicles to specially constructed mobile platforms and are utilized as test beds for developing concepts in the application of robotics to interior and exterior physical security. Actuators control the vehicle speed, brakes, and steering through manual input from a remote driving station or through some level of digital computer control. On-board processing may include simple vehicle control functions or may allow for unmanned, autonomous operation. Communication links are provided for digital communication between control computers, television transmission for vehicle vision, and voice for local control. With these vehicles, SNL can develop, test, and evaluate sensors, processing requirements, various methods of actuator implementation, operator controlled feedback requirements, and vehicle operations. A description of the major features and uses for each of the vehicles in the fleet is provided

  2. Mobile robot vehicles for physical security

    International Nuclear Information System (INIS)

    McGovern, D.E.

    1987-06-01

    A fleet of vehicles is being developed and maintained by Sandia National Labs for studies in remote control and autonomous operation. These vehicles range from modified commercial vehicles to specially constructed mobile platforms and are utilized as test beds for developing concepts in the application of robotics to interior and exterior physical security. Actuators control the vehicle speed, brakes, and steering through manual input from a remote driving station or through some level of digital computer control. On-board processing may include simple vehicle control functions or may allow for unmanned, autonomous operation. Communication links are provided for digital communication between control computers, television transmission for vehicle vision, and voice for local control. With these vehicles, SNL can develop, test, and evaluate sensors, processing requirements, various methods of actuator implementation, operator controlled feedback requirements, and vehicle operations. A description of the major features and uses for each of the vehicles in the fleet is provided. 4 refs., 1 fig., 1 tab

  3. The design of electric vehicle intelligent charger

    Science.gov (United States)

    Xu, Yangyang; Wang, Ying

    2018-05-01

    As the situation of the lack of energy and environment pollution deteriorates rapidly, electric vehicle, a new type of traffic tool, is being researched worldwide. As the core components of electric vehicle, the battery and charger's performance play an important roles in the quality of electric vehicle. So the design of the Electric Vehicle Intelligent Charger based on language-C is designed in this paper. The hardware system is used to produce the input signals of Electric Vehicle Intelligent Charger. The software system adopts the language-C software as development environment. The design can accomplish the test of the parametric such as voltage-current and temperature.

  4. Compressed Air Production Using Vehicle Suspension

    OpenAIRE

    Ninad Arun Malpure; Sanket Nandlal Bhansali

    2015-01-01

    Abstract Generally compressed air is produced using different types of air compressors which consumes lot of electric energy and is noisy. In this paper an innovative idea is put forth for production of compressed air using movement of vehicle suspension which normal is wasted. The conversion of the force energy into the compressed air is carried out by the mechanism which consists of the vehicle suspension system hydraulic cylinder Non-return valve air compressor and air receiver. We are co...

  5. Adaptive Control Allocation for Fault Tolerant Overactuated Autonomous Vehicles

    Science.gov (United States)

    2007-11-01

    Tolerant Overactuated Autonomous Vehicles Casavola, A.; Garone, E. (2007) Adaptive Control Allocation for Fault Tolerant Overactuated Autonomous ...Adaptive Control Allocation for Fault Tolerant Overactuated Autonomous Vehicles 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...Tolerant Overactuated Autonomous Vehicles 3.2 - 2 RTO-MP-AVT-145 UNCLASSIFIED/UNLIMITED Control allocation problem (CAP) - Given a virtual input v(t

  6. Vehicle health management for guidance, navigation and control systems

    Science.gov (United States)

    Radke, Kathleen; Frazzini, Ron; Bursch, Paul; Wald, Jerry; Brown, Don

    1993-01-01

    The objective of the program was to architect a vehicle health management (VHM) system for space systems avionics that assures system readiness for launch vehicles and for space-based dormant vehicles. The platforms which were studied and considered for application of VHM for guidance, navigation and control (GN&C) included the Advanced Manned Launch System (AMLS), the Horizontal Landing-20/Personnel Launch System (HL-20/PLS), the Assured Crew Return Vehicle (ACRV) and the Extended Duration Orbiter (EDO). This set was selected because dormancy and/or availability requirements are driving the designs of these future systems.

  7. Using Multimodal Input for Autonomous Decision Making for Unmanned Systems

    Science.gov (United States)

    Neilan, James H.; Cross, Charles; Rothhaar, Paul; Tran, Loc; Motter, Mark; Qualls, Garry; Trujillo, Anna; Allen, B. Danette

    2016-01-01

    Autonomous decision making in the presence of uncertainly is a deeply studied problem space particularly in the area of autonomous systems operations for land, air, sea, and space vehicles. Various techniques ranging from single algorithm solutions to complex ensemble classifier systems have been utilized in a research context in solving mission critical flight decisions. Realized systems on actual autonomous hardware, however, is a difficult systems integration problem, constituting a majority of applied robotics development timelines. The ability to reliably and repeatedly classify objects during a vehicles mission execution is vital for the vehicle to mitigate both static and dynamic environmental concerns such that the mission may be completed successfully and have the vehicle operate and return safely. In this paper, the Autonomy Incubator proposes and discusses an ensemble learning and recognition system planned for our autonomous framework, AEON, in selected domains, which fuse decision criteria, using prior experience on both the individual classifier layer and the ensemble layer to mitigate environmental uncertainty during operation.

  8. Piecewise affine control for fast unmanned ground vehicles

    OpenAIRE

    Benine Neto , André; Grand , Christophe

    2012-01-01

    International audience; Unmanned ground vehicles (UGV) may experience skidding when moving at high speeds, and therefore have its safety jeopardized. For this reason the nonlinear dynamics of lateral tire forces must be taken into account into the design of steering controllers for autonomous vehicles. This paper presents the design of a state feedback piecewise affine controller applied to an UGV to coordinate the steering and torque distribution inputs in order to reduce vehicle skidding on...

  9. Vehicle Speed Estimation and Forecasting Methods Based on Cellular Floating Vehicle Data

    Directory of Open Access Journals (Sweden)

    Wei-Kuang Lai

    2016-02-01

    Full Text Available Traffic information estimation and forecasting methods based on cellular floating vehicle data (CFVD are proposed to analyze the signals (e.g., handovers (HOs, call arrivals (CAs, normal location updates (NLUs and periodic location updates (PLUs from cellular networks. For traffic information estimation, analytic models are proposed to estimate the traffic flow in accordance with the amounts of HOs and NLUs and to estimate the traffic density in accordance with the amounts of CAs and PLUs. Then, the vehicle speeds can be estimated in accordance with the estimated traffic flows and estimated traffic densities. For vehicle speed forecasting, a back-propagation neural network algorithm is considered to predict the future vehicle speed in accordance with the current traffic information (i.e., the estimated vehicle speeds from CFVD. In the experimental environment, this study adopted the practical traffic information (i.e., traffic flow and vehicle speed from Taiwan Area National Freeway Bureau as the input characteristics of the traffic simulation program and referred to the mobile station (MS communication behaviors from Chunghwa Telecom to simulate the traffic information and communication records. The experimental results illustrated that the average accuracy of the vehicle speed forecasting method is 95.72%. Therefore, the proposed methods based on CFVD are suitable for an intelligent transportation system.

  10. Mars Ascent Vehicle Needs Technology Development with a Focus on High Propellant Fractions

    Science.gov (United States)

    Whitehead, J. C.

    2018-04-01

    Launching from Mars to orbit requires a miniature launch vehicle, beyond any known spacecraft propulsion. The Mars Ascent Vehicle (MAV) needs an unusually high propellant mass fraction. MAV mass has high leverage for the cost of Mars Sample Return.

  11. Canadians' perceptions of electric vehicle technology : final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-03-15

    While Canadians seem to appreciate some of the possible benefits of electric vehicle technology (EVT), they generally lack knowledge or understanding of EVTs, in terms of how they operate and what types of EVT vehicles are currently available. This paper described the challenges associated with the adoption of EVT in Canada. In particular, it described a research program that was designed to assess Canadians' attitudes towards electric vehicle technology, in order to provide input into the development of a technology roadmap and its implementation plan, to provide input into communications plans and strategies to promote greater awareness and acceptance of the technology, and to establish baseline attitudinal indicators that could be tracked over time. Specifically, the objectives of the paper were to measure the Canadian public's levels of awareness, knowledge and comfort with EVTs; determine the motivators to adoption of EVT; determine the barriers to broader acceptance and market diffusion of EVT; and identify key group differences. Topics that were discussed included public awareness and knowledge of electric vehicle technology; and interest in plug-in hybrid vehicles and battery-electric vehicles, including perceived advantages and barriers. A profile of drivers consisted of a review of vehicle type; vehicle use profile; size of vehicle; considerations when choosing a vehicle; personal orientation to vehicle ownership; attitudes about vehicle choice; and attitudes about vehicles and air quality. Descriptions of the quantitative and qualitative methods employed in conducting the research, as well as the survey questionnaire and discussion guide were included as appendices. It was concluded that the small proportion of Canadian drivers who see vehicles as a form of personal expression are more likely to be interested in a future plug-in hybrid electric vehicles purchase or rental. tabs., figs., appendices.

  12. EADS Roadmap for Launch Vehicles

    Science.gov (United States)

    Eymar, Patrick; Grimard, Max

    2002-01-01

    still think about the future, especially at industry level in order to make the most judicious choices in technologies, vehicle types as well as human resources and facilities specialization (especially after recent merger moves). and production as prime contractor, industrial architect or stage provider have taken benefit of this expertise and especially of all the studies ran under national funding and own financing on reusable vehicles and ground/flight demonstrators have analyzed several scenarios. VEHICLES/ASTRIUM SI strategy w.r.t. launch vehicles for the two next decades. Among the main inputs taken into account of course visions of the market evolutions have been considered, but also enlargement of international cooperations and governments requests and supports (e.g. with the influence of large international ventures). 1 patrick.eymar@lanceurs.aeromatra.com 2

  13. The dynamic behaviour of a railway mine vehicle

    Energy Technology Data Exchange (ETDEWEB)

    van Manen, P.; Brickle, B.V.

    1983-06-01

    The paper describes a mathematical model of a railway mine vehicle which is capable of predicting its dynamic behaviour in response to track inputs. The predictions of the model have been compared with the results of tests carried out on a new high speed mine vehicle and the correlation shown is good. The model yields frequency response information for the vehicle and may be used to simulate dynamic behaviour in response to track irregularities. (4 refs.)

  14. Mars Sample Return: Launch and Detection Strategies for Orbital Rendezvous

    Science.gov (United States)

    Woolley, Ryan C.; Mattingly, Richard L.; Riedel, Joseph E.; Sturm, Erick J.

    2011-01-01

    This study sets forth conceptual mission design strategies for the ascent and rendezvous phase of the proposed NASA/ESA joint Mars Sample Return Campaign. The current notional mission architecture calls for the launch of an acquisition/ caching rover in 2018, an Earth return orbiter in 2022, and a fetch rover with ascent vehicle in 2024. Strategies are presented to launch the sample into a nearly coplanar orbit with the Orbiter which would facilitate robust optical detection, orbit determination, and rendezvous. Repeating ground track orbits existat 457 and 572 km which would provide multiple launch opportunities with similar geometries for detection and rendezvous.

  15. Mars Sample Return Landed with Red Dragon

    Science.gov (United States)

    Stoker, Carol R.; Lemke, Lawrence G.

    2013-01-01

    A Mars Sample Return (MSR) mission is the highest priority science mission for the next decade as recommended by the recent Decadal Survey of Planetary Science. However, an affordable program to carry this out has not been defined. This paper describes a study that examined use of emerging commercial capabilities to land the sample return elements, with the goal of reducing mission cost. A team at NASA Ames examined the feasibility of the following scenario for MSR: A Falcon Heavy launcher injects a SpaceX Dragon crew capsule and trunk onto a Trans Mars Injection trajectory. The capsule is modified to carry all the hardware needed to return samples collected on Mars including a Mars Ascent Vehicle (MAV), an Earth Return Vehicle (ERV) and Sample Collection and Storage hardware. The Dragon descends to land on the surface of Mars using SuperSonic Retro Propulsion (SSRP) as described by Braun and Manning [IEEEAC paper 0076, 2005]. Samples are acquired and deliverd to the MAV by a prelanded asset, possibly the proposed 2020 rover. After samples are obtained and stored in the ERV, the MAV launches the sample-containing ERV from the surface of Mars. We examined cases where the ERV is delivered to either low Mars orbit (LMO), C3 = 0 (Mars escape), or an intermediate energy state. The ERV then provides the rest of the energy (delta V) required to perform trans-Earth injection (TEI), cruise, and insertion into a Moon-trailing Earth Orbit (MTEO). A later mission, possibly a crewed Dragon launched by a Falcon Heavy (not part of the current study) retrieves the sample container, packages the sample, and performs a controlled Earth re-entry to prevent Mars materials from accidentally contaminating Earth. The key analysis methods used in the study employed a set of parametric mass estimating relationships (MERs) and standard aerospace analysis software codes modified for the MAV class of launch vehicle to determine the range of performance parameters that produced converged

  16. Motion Planning of Autonomous Vehicles on a Dual Carriageway without Speed Lanes

    Directory of Open Access Journals (Sweden)

    Rahul Kala

    2015-01-01

    Full Text Available The problem of motion planning of an autonomous vehicle amidst other vehicles on a straight road is considered. Traffic in a number of countries is unorganized, where the vehicles do not move within predefined speed lanes. In this paper, we formulate a mechanism wherein an autonomous vehicle may travel on the “wrong” side in order to overtake a vehicle. Challenges include assessing a possible overtaking opportunity, cooperating with other vehicles, partial driving on the “wrong” side of the road and safely going to and returning from the “wrong” side. The experimental results presented show vehicles cooperating to accomplish overtaking manoeuvres.

  17. Application of artificial neural network for the prediction of stock market returns: The case of the Japanese stock market

    International Nuclear Information System (INIS)

    Qiu, Mingyue; Song, Yu; Akagi, Fumio

    2016-01-01

    Accurate prediction of stock market returns is a very challenging task because of the highly nonlinear nature of the financial time series. In this study, we apply an artificial neural network (ANN) that can map any nonlinear function without a prior assumption to predict the return of the Japanese Nikkei 225 index. (1) To improve the effectiveness of prediction algorithms, we propose a new set of input variables for ANN models. (2) To verify the prediction ability of the selected input variables, we predict returns for the Nikkei 225 index using the classical back propagation (BP) learning algorithm. (3) Global search techniques, i.e., a genetic algorithm (GA) and simulated annealing (SA), are employed to improve the prediction accuracy of the ANN and overcome the local convergence problem of the BP algorithm. It is observed through empirical experiments that the selected input variables were effective to predict stock market returns. A hybrid approach based on GA and SA improve prediction accuracy significantly and outperform the traditional BP training algorithm.

  18. On distributed model predictive control for vehicle platooning with a recursive feasibility guarantee

    NARCIS (Netherlands)

    Shi, Shengling; Lazar, Mircea

    2017-01-01

    This paper proposes a distributed model predictive control algorithm for vehicle platooning and more generally networked systems in a chain structure. The distributed models of the vehicle platoon are coupled through the input of the preceding vehicles. Using the principles of robust model

  19. International Trade in Intermediate Inputs: The Case of the Automobile Industry

    OpenAIRE

    Markus Diehl

    2001-01-01

    International trade statistics and input-output tables are analyzed in order to test the hypothesis that international production networks have become more relevant. The share of imported inputs in the gross output value of the motor vehicle industry has grown significantly during the last two decades. Moreover, some low-income countries have become strong exporters of automobile parts, but this trade is mainly regional rather than global. Detailed results are presented in case studies on fou...

  20. Productivity and efficiency analysis of privatized hydroelectric generation with a sometimes free input

    Science.gov (United States)

    Halabi, Claudia Elizabeth

    2000-10-01

    In this paper I use a stochastic distance frontier approach to assess the performance of Chile's hydroelectric industry, which operates within a regulatory framework designed to achieve a competitive outcome. An occasionally free input, water, is the sole energy input. The econometric analysis indicates substantial technical and allocative inefficiencies as well as volatile productivity scores, due presumably to the volatility of the energy input. Some allocative inefficiencies have diminished dramatically as the time under deregulation has grown. The Lerner index suggests that firms in the industry enjoy some degree of market power, reflected by prices that exceed marginal costs. This market power is consistent with operation within a centralized dispatch center, as predicted by a strategic bidding model. I also find that run-of-river plants exhibit increasing returns to scale, while plants relying on dams show slightly diminishing returns. The shadow marginal cost for run-of-river plants is found to be close to zero. Substantial cost savings could be realized if firms in Chile's hydro-electric generation industry were to operate efficiently.

  1. Vibration Energy Harvesting on Vehicle Suspension Using Rotary and Linear Electromagnetic Generator

    Directory of Open Access Journals (Sweden)

    Arif Indro Sultoni

    2013-04-01

    Full Text Available In this paper, we discuss comparation of vehicle vibration energy harvesting between rotary and linear electromagnetic generator. We construct the two model of energy harvester mechanism and then analyze both of energy absorbtion and vehicle comfortability. Furthermore, we analyze both of energy absorbtion and vehicle comfortability. Vehicle is modeled as quarter car. Rotarty generator harvests 2.5 x 10-4 Watt. The other hand, linear generator has viscous characteristic and capable to generates 90 Watts with 12 Volt power supply for 0.03 m amplitude of bumpy road input. Linear generator reduces oscillation with 1.2 sec settling time. It is more comfort than the angular which has 3 sec in settling time. With unnevenees road input, mean power of this generator is 64 Watt.

  2. Radiation monitor for surveillance of moving vehicles

    International Nuclear Information System (INIS)

    Dvorak, R.F.

    1985-09-01

    A radiation monitor has been developed that will scan each vehicle leaving the Clinton P. Anderson Los Alamos Meson Physics Facility site. If an increase in radiation level is sensed, an alarm light and a Klaxon horn are activated, inviting the driver to return to the Health Physics office for check. A photograph showing the vehicle license number is also taken. A radiation source that doubles the detector count rate when stationary will cause an alarm at vehicle speeds up to about 24 km/h (15 mph). The technique used to prevent false alarms because of radiations from nearby buildings or from plumes of low-level radioactive gas is described. 9 figs

  3. Locating Depots for Capacitated Vehicle Routing

    DEFF Research Database (Denmark)

    Gørtz, Inge Li; Nagarajan, Viswanath

    2016-01-01

    We study a location-routing problem in the context of capacitated vehicle routing. The input to the k-location capacitated vehicle routing problem (k-LocVRP) consists of a set of demand locations in a metric space and a fleet of k identical vehicles, each of capacity Q. The objective is to locate k...... depots, one for each vehicle, and compute routes for the vehicles so that all demands are satisfied and the total cost is minimized. Our main result is a constant-factor approximation algorithm for k-LocVRP. In obtaining this result, we introduce a common generalization of the k-median and minimum...... spanning tree problems (called k median forest), which might be of independent interest. We give a local-search based (3+ε)-approximation algorithm for k median forest, which leads to a (12+ε)-approximation algorithm for k-LocVRP, for any constant ε>0....

  4. Locating Depots for Capacitated Vehicle Routing

    DEFF Research Database (Denmark)

    Gørtz, Inge Li; Nagarajan, Viswanath

    2016-01-01

    depots, one for each vehicle, and compute routes for the vehicles so that all demands are satisfied and the total cost is minimized. Our main result is a constant-factor approximation algorithm for k-LocVRP. In obtaining this result, we introduce a common generalization of the k-median and minimum...... spanning tree problems (called k median forest), which might be of independent interest. We give a local-search based (3+ε)-approximation algorithm for k median forest, which leads to a (12+ε)-approximation algorithm for k-LocVRP, for any constant ε>0.......We study a location-routing problem in the context of capacitated vehicle routing. The input to the k-location capacitated vehicle routing problem (k-LocVRP) consists of a set of demand locations in a metric space and a fleet of k identical vehicles, each of capacity Q. The objective is to locate k...

  5. Crew Exploration Vehicle Service Module Ascent Abort Coverage

    Science.gov (United States)

    Tedesco, Mark B.; Evans, Bryan M.; Merritt, Deborah S.; Falck, Robert D.

    2007-01-01

    The Crew Exploration Vehicle (CEV) is required to maintain continuous abort capability from lift off through destination arrival. This requirement is driven by the desire to provide the capability to safely return the crew to Earth after failure scenarios during the various phases of the mission. This paper addresses abort trajectory design considerations, concept of operations and guidance algorithm prototypes for the portion of the ascent trajectory following nominal jettison of the Launch Abort System (LAS) until safe orbit insertion. Factors such as abort system performance, crew load limits, natural environments, crew recovery, and vehicle element disposal were investigated to determine how to achieve continuous vehicle abort capability.

  6. A price-responsive dispatching strategy for Vehicle-to-Grid: An economic evaluation applied to the case of Singapore

    Science.gov (United States)

    Pelzer, Dominik; Ciechanowicz, David; Aydt, Heiko; Knoll, Alois

    2014-06-01

    Employing electric vehicles as short-term energy storage could improve power system stability and at the same time create a new income source for vehicle owners. In this paper, the economic viability of this concept referred to as Vehicle-to-Grid is investigated. For this purpose, a price-responsive charging and dispatching strategy built upon temporally resolved electricity market data is presented. This concept allows vehicle owners to maximize returns by restricting market participation to profitable time periods. As a case study, this strategy is then applied using the example of Singapore. It is shown that an annual loss of S 1000 resulting from a non-price-responsive strategy as employed in previous works can be turned into a S 130 profit by applying the price-responsive approach. In addition to this scenario, realistic mobility patterns which restrict the temporal availability of vehicles are considered. In this case, profits in the range of S 21-S 121 are achievable. Returns in this order of magnitude are not expected to make Vehicle-to-Grid a viable business case, sensitivity analyses, however, show that improved technical parameters could increase profitability. It is further assumed that employing the price-responsive strategy to other national markets may yield significantly greater returns.

  7. EROI of crystalline silicon photovoltaics : Variations under different assumptions regarding manufacturing energy inputs and energy output

    OpenAIRE

    Lundin, Johan

    2013-01-01

    Installed photovoltaic nameplate power have been growing rapidly around the worldin the last few years. But how much energy is returned to society (i.e. net energy) by this technology, and which factors contribute the most to the amount of energy returned? The objective of this thesis was to examine the importance of certain inputs and outputs along the solar panel production chain and their effect on the energy return on (energy) investment (EROI) for crystalline wafer-based photovoltaics. A...

  8. Vision-GPS Fusion for Guidance of an Autonomous Vehicle in Row Crops

    DEFF Research Database (Denmark)

    Bak, Thomas

    2001-01-01

    This paper presents a real-time localization system for an autonomous vehicle passing through 0.25 m wide crop rows at 6 km/h. Localization is achieved by fusion of mea-surements from a row guidance sensor and a GPS receiver. Conventional agricultural practice applies inputs such as herbicide...... at a constant rate ignoring the spatial variability in weed, soil, and crop. Sensing with a guided vehicle allow cost effective mapping of field variability and inputs may be adjusted accordingly. Essential to such a vehicle is real-time localization. GPS allow precise absolute sensing but it is not practical...... to guide the vehicle relative to the crop rows on an absolute coordinate. A row guidance sensor is therefore included to sense the position relative to the rows. The vehicle path in the field is re-planned online in order to allow for crop row irregularities sensed by the row sensor. The path generation...

  9. Aerospace Vehicle Design, Spacecraft Section. Volume 1: Project Groups 3-5

    Science.gov (United States)

    1989-01-01

    Three groups of student engineers in an aerospace vehicle design course present their designs for a vehicle that can be used to resupply the Space Station Freedom and provide an emergency crew return to earth capability. The vehicle's requirements include a lifetime that exceeds six years, low cost, the capability for withstanding pressurization, launch, orbit, and reentry hazards, and reliability. The vehicle's subsystems are analyzed. These subsystems are structures, communication and command data systems, attitude and articulation control, life support and crew systems, power and propulsion, reentry and recovery systems, and mission management, planning, and costing.

  10. Stability Simulation of a Vehicle with Wheel Active Steering

    Directory of Open Access Journals (Sweden)

    Brabec Pavel

    2016-01-01

    Full Text Available This paper deals with the possibility of increasing the vehicle driving stability at a higher speed. One of the ways how to achieve higher stability is using the 4WS system. Mathematical description of vehicle general movement is a very complex task. For simulation, models which are aptly simplified are used. For the first approach, so-called single-truck vehicle model (often linear is usually used. For the simulation, we have chosen to extend the model into a two-truck one, which includes the possibility to input more vehicle parameters. Considering the 4WS system, it is possible to use a number of potential regulations. In our simulation model, the regulation system with compound coupling was used. This type of regulation turns the rear wheels depending on the input parameters of the system (steering angle of the front wheels and depending on the output moving quantities of the vehicle, most frequently the yaw rate. Criterion for compensation of lateral deflection centre of gravity angle is its zero value, or more precisely the zero value of its first-order derivative. Parameters and set-up of the simulation model were done in conjunction with the dSAPACE software. Reference performances of the vehicle simulation model were made through the defined manoeuvres. But the simulation results indicate that the rear-wheels steering can have a positive effect on the vehicle movement stability, especially when changing the driving direction at high speed.

  11. Steering redundancy for self-driving vehicles using differential braking

    Science.gov (United States)

    Jonasson, M.; Thor, M.

    2018-05-01

    This paper describes how differential braking can be used to turn a vehicle in the context of providing fail-operational control for self-driving vehicles. Two vehicle models are developed with differential input. The models are used to explain the bounds of curvature that differential braking provides and they are then validated with measurements in a test vehicle. Particular focus is paid on wheel suspension effects that significantly influence the obtained curvature. The vehicle behaviour and its limitations due to wheel suspension effects are, owing to the vehicle models, defined and explained. Finally, a model-based controller is developed to control the vehicle curvature during a fault by differential braking. The controller is designed to compensate for wheel angle disturbance that is likely to occur during the control event.

  12. Exploratory study : vehicle mileage fees in Texas.

    Science.gov (United States)

    2011-01-01

    This project evaluates Vehicle Mileage (VM) fees as a possible funding mechanism for meeting the State of Texas : long-term transportation needs. Researchers conducted listening sessions with the general public and stakeholders to : gather input o...

  13. A General Mathematical Framework for Calculating Systems-Scale Efficiency of Energy Extraction and Conversion: Energy Return on Investment (EROI and Other Energy Return Ratios

    Directory of Open Access Journals (Sweden)

    Adam R. Brandt

    2011-08-01

    Full Text Available The efficiencies of energy extraction and conversion systems are typically expressed using energy return ratios (ERRs such as the net energy ratio (NER or energy return on investment (EROI. A lack of a general mathematical framework prevents inter-comparison of NER/EROI estimates between authors: methods used are not standardized, nor is there a framework for succinctly reporting results in a consistent fashion. In this paper we derive normalized mathematical forms of four ERRs for energy extraction and conversion pathways. A bottom-up (process model formulation is developed for an n-stage energy harvesting and conversion pathway with various system boundaries. Formations with the broadest system boundaries use insights from life cycle analysis to suggest a hybrid process model/economic input output based framework. These models include indirect energy consumption due to external energy inputs and embodied energy in materials. Illustrative example results are given for simple energy extraction and conversion pathways. Lastly, we discuss the limitations of this approach and the intersection of this methodology with “top-down” economic approaches.

  14. The long-term development of the energy input in transportation, 1970-2020

    Energy Technology Data Exchange (ETDEWEB)

    Meiren, P B [E.F.C.E.E., Mechelen (Belgium)

    1996-12-01

    This paper is a - modest - statistical and economic analysis of the energy input in the transportation sector over the past twenty-five years (1970 - 1995) and an attempt at looking ahead over the next twenty-five years (1995 - 2020). After World War II passenger cars and trucks became the means of transportation par excellence and are still the main vehicle for moving around, both men and freight. Energy input statistics were born. Let us see what they teach us. (EG)

  15. Development of the Tri-ATHLETE Lunar Vehicle Prototype

    Science.gov (United States)

    Heverly, Matt; Matthews, Jaret; Frost, Matt; Quin, Chris

    2010-01-01

    The Tri-ATHLETE (All Terrain Hex Limed Extra Terrestrial Explorer) vehicle is the second generation of a wheel-on-limb vehicle being developed to support the return of humans to the lunar surface. This paper describes the design, assembly, and test of the Tri-ATHLETE robotic system with a specific emphasis on the limb joint actuators. The design and implementation of the structural components is discussed, and a novel and low cost approach to approximating flight-like cabling is also presented. The paper concludes with a discussion of the "second system effect" and other lessons learned as well as results from a three week long field trial of the vehicle in the Arizona desert.

  16. Modeling and predicting low-speed vehicle emissions as a function of driving kinematics.

    Science.gov (United States)

    Hao, Lijun; Chen, Wei; Li, Lei; Tan, Jianwei; Wang, Xin; Yin, Hang; Ding, Yan; Ge, Yunshan

    2017-05-01

    An instantaneous emission model was developed to model and predict the real driving emissions of the low-speed vehicles. The emission database used in the model was measured by using portable emission measurement system (PEMS) under actual traffic conditions in the rural area, and the characteristics of the emission data were determined in relation to the driving kinematics (speed and acceleration) of the low-speed vehicle. The input of the emission model is driving cycle, and the model requires instantaneous vehicle speed and acceleration levels as input variables and uses them to interpolate the pollutant emission rate maps to calculate the transient pollutant emission rates, which will be accumulated to calculate the total emissions released during the whole driving cycle. And the vehicle fuel consumption was determined through the carbon balance method. The model predicted the emissions and fuel consumption of an in-use low-speed vehicle type model, which agreed well with the measured data. Copyright © 2016. Published by Elsevier B.V.

  17. Energy Consumption Prediction for Electric Vehicles Based on Real-World Data

    Directory of Open Access Journals (Sweden)

    Cedric De Cauwer

    2015-08-01

    Full Text Available Electric vehicle (EV energy consumption is variable and dependent on a number of external factors such as road topology, traffic, driving style, ambient temperature, etc. The goal of this paper is to detect and quantify correlations between the kinematic parameters of the vehicle and its energy consumption. Real-world data of EV energy consumption are used to construct the energy consumption calculation models. Based on the vehicle dynamics equation as underlying physical model, multiple linear regression is used to construct three models. Each model uses a different level of aggregation of the input parameters, allowing predictions using different types of available input parameters. One model uses aggregated values of the kinematic parameters of trips. This model allows prediction with basic, easily available input parameters such as travel distance, travel time, and temperature. The second model extends this by including detailed acceleration data. The third model uses the raw data of the kinematic parameters as input parameters to predict the energy consumption. Using detailed values of kinematic parameters for the prediction in theory increases the link between the statistical model and its underlying physical principles, but requires these parameters to be available as input in order to make predictions. The first two models show similar results. The third model shows a worse fit than the first two, but has a similar accuracy. This model has great potential for future improvement.

  18. Vehicle Lightweighting: 40% and 45% Weight Savings Analysis: Technical Cost Modeling for Vehicle Lightweighting

    Energy Technology Data Exchange (ETDEWEB)

    Mascarin, Anthony [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hannibal, Ted [Idaho National Lab. (INL), Idaho Falls, ID (United States); Raghunathan, Anand [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ivanic, Ziga [Idaho National Lab. (INL), Idaho Falls, ID (United States); Francfort, James [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-04-01

    The U.S. Department of Energy’s Vehicle Technologies Office, Materials area commissioned a study to model and assess manufacturing economics of alternative design and production strategies for a series of lightweight vehicle concepts. The strategic targets were a 40% and a 45% mass reduction relative to a standard North American midsize passenger sedan at an effective cost of $3.42 per pound (lb) saved. The baseline vehicle was an average of several available vehicles in this class. Mass and cost breakdowns from several sources were used, including original equipment manufacturers’ (OEMs’) input through U.S. Department of Energy’s Vehicle Technologies Office programs and public presentations, A2Mac1 LLC’s teardown information, Lotus Engineering Limited and FEV, Inc. breakdowns in their respective lightweighting studies, and IBIS Associates, Inc.’s decades of experience in automotive lightweighting and materials substitution analyses. Information on lightweighting strategies in this analysis came from these same sources and the ongoing U.S. Department of Energy-funded Vehma International of America, Inc. /Ford Motor Company Multi-Material Lightweight Prototype Vehicle Demonstration Project, the Aluminum Association Transportation Group, and many United States Council for Automotive Research’s/United States Automotive Materials Partnership LLC lightweight materials programs.

  19. Design of a data-driven predictive controller for start-up process of AMT vehicles.

    Science.gov (United States)

    Lu, Xiaohui; Chen, Hong; Wang, Ping; Gao, Bingzhao

    2011-12-01

    In this paper, a data-driven predictive controller is designed for the start-up process of vehicles with automated manual transmissions (AMTs). It is obtained directly from the input-output data of a driveline simulation model constructed by the commercial software AMESim. In order to obtain offset-free control for the reference input, the predictor equation is gained with incremental inputs and outputs. Because of the physical characteristics, the input and output constraints are considered explicitly in the problem formulation. The contradictory requirements of less friction losses and less driveline shock are included in the objective function. The designed controller is tested under nominal conditions and changed conditions. The simulation results show that, during the start-up process, the AMT clutch with the proposed controller works very well, and the process meets the control objectives: fast clutch lockup time, small friction losses, and the preservation of driver comfort, i.e., smooth acceleration of the vehicle. At the same time, the closed-loop system has the ability to reject uncertainties, such as the vehicle mass and road grade.

  20. The ParaShield Entry Vehicle Concept: Basic Theory and Flight Test Development

    OpenAIRE

    Akin, David

    1990-01-01

    With the emergence of microsatellite launch vehicle technology and the development of interest in space commercialization, there is a renewed need for entry vehicle technology to return mass from low earth orbit. This paper documents the ParaShield concept of the Space Systems Laboratory, which is an ultra-low ballistic coefficient (ULβ) entry vehicle. Trajectory simulations show that as the ballistic coefficient is lowered into the range of 100-150 Pa (2-3lb/ft2) the total heat load and peak...

  1. Remanufacturing lot-sizing under alternative perceptions of returned units' quality

    Directory of Open Access Journals (Sweden)

    Zikopoulos, C.

    2012-01-01

    Full Text Available One of the critical parameters in reverse supply chain management is the increased variability of the quality condition of used, returned products. The volatile nature of returns' quality often dictates the establishment of quality assessment procedures and the development of technologies that facilitate the fast, accurate and inexpensive classification of returns. The appropriate degree in which a firm has to allocate resources for acquiring information on the quality of returned units, naturally, depends on the anticipated improvement of recovery activities' profitability. Therefore, the quantification of the savings associated with confronting or resolving quality uncertainty is a necessary input during the determination of the proper recovery procedures' configuration. In the current paper, we study a remanufacturing system in a multi-period setting in which returns' quality information is exploited during remanufacturing planning. However, in the decision-making process, certain aspects of the problem examined, such as the quantification of shortage cost, are overlooked or simplified. The objective is to examine the advisability of acquiring advanced quality information in order to be used during sub-optimal decision-making processes, in comparison with alternative policies which do not take explicitly into account returns' quality information. Moreover, through an extensive numerical analysis we examine the implications of alternative considerations regarding returned units' quality on remanufacturing planning, lead-time and service-levels and evaluate their impact on the overall system operational cost.

  2. Performance Efficient Launch Vehicle Recovery and Reuse

    Science.gov (United States)

    Reed, John G.; Ragab, Mohamed M.; Cheatwood, F. McNeil; Hughes, Stephen J.; Dinonno, J.; Bodkin, R.; Lowry, Allen; Brierly, Gregory T.; Kelly, John W.

    2016-01-01

    For decades, economic reuse of launch vehicles has been an elusive goal. Recent attempts at demonstrating elements of launch vehicle recovery for reuse have invigorated a debate over the merits of different approaches. The parameter most often used to assess the cost of access to space is dollars-per-kilogram to orbit. When comparing reusable vs. expendable launch vehicles, that ratio has been shown to be most sensitive to the performance lost as a result of enabling the reusability. This paper will briefly review the historical background and results of recent attempts to recover launch vehicle assets for reuse. The business case for reuse will be reviewed, with emphasis on the performance expended to recover those assets, and the practicality of the most ambitious reuse concept, namely propulsive return to the launch site. In 2015, United Launch Alliance (ULA) announced its Sensible, Modular, Autonomous Return Technology (SMART) reuse plan for recovery of the booster module for its new Vulcan launch vehicle. That plan employs a non-propulsive approach where atmospheric entry, descent and landing (EDL) technologies are utilized. Elements of such a system have a wide variety of applications, from recovery of launch vehicle elements in suborbital trajectories all the way to human space exploration. This paper will include an update on ULA's booster module recovery approach, which relies on Hypersonic Inflatable Aerodynamic Decelerator (HIAD) and Mid-Air Retrieval (MAR) technologies, including its concept of operations (ConOps). The HIAD design, as well as parafoil staging and MAR concepts, will be discussed. Recent HIAD development activities and near term plans including scalability, next generation materials for the inflatable structure and heat shield, and gas generator inflation systems will be provided. MAR topics will include the ConOps for recovery, helicopter selection and staging, and the state of the art of parachute recovery systems using large parafoils

  3. Resolution of First- and Second-Order Linear Differential Equations with Periodic Inputs by a Computer Algebra System

    Directory of Open Access Journals (Sweden)

    M. Legua

    2008-01-01

    Full Text Available In signal processing, a pulse means a rapid change in the amplitude of a signal from a baseline value to a higher or lower value, followed by a rapid return to the baseline value. A square wave function may be viewed as a pulse that repeats its occurrence periodically but the return to the baseline value takes some time to happen. When these periodic functions act as inputs in dynamic systems, the standard tool commonly used to solve the associated initial value problem (IVP is Laplace transform and its inverse. We show how a computer algebra system may also provide the solution of these IVP straight forwardly by adequately introducing the periodic input.

  4. Shifting and power sharing control of a novel dual input clutchless transmission for electric vehicles

    Science.gov (United States)

    Liang, Jiejunyi; Yang, Haitao; Wu, Jinglai; Zhang, Nong; Walker, Paul D.

    2018-05-01

    To improve the overall efficiency of electric vehicles and guarantee the driving comfort and vehicle drivability under the concept of simplifying mechanism complexity and minimizing manufacturing cost, this paper proposes a novel clutchless power-shifting transmission system with shifting control strategy and power sharing control strategy. The proposed shifting strategy takes advantage of the transmission architecture to achieve power-on shifting, which greatly improves the driving comfort compared with conventional automated manual transmission, with a bump function based shifting control method. To maximize the overall efficiency, a real-time power sharing control strategy is designed to solve the power distribution problem between the two motors. Detailed mathematical model is built to verify the effectiveness of the proposed methods. The results demonstrate the proposed strategies considerably improve the overall efficiency while achieve non-interrupted power-on shifting and maintain the vehicle jerk during shifting under an acceptable threshold.

  5. Options for human ``return to the moon'' using tomorrow's SSTO, ISRU, and LOX-augmented NTR technologies

    Science.gov (United States)

    Borowski, Stanley K.

    1996-03-01

    The feasibility of conducting human missions to the Moon is examined assuming the use of three ``high leverage'' technologies: (1) a single-stage-to-orbit (SSTO) launch vehicle, (2) ``in-situ'' resource utilization (ISRU)—specifically ``lunar-derived'' liquid oxygen (LUNOX), and (3) LOX-augmented nuclear thermal rocket (LANTR) propulsion. Lunar transportation system elements consisting of a LANTR-powered lunar transfer vehicle (LTV) and a chemical propulsion lunar landing/Earth return vehicle (LERV) are configured to fit within the ``compact'' dimensions of the SSTO cargo bay (diameter: 4.6 m/length: 9.0 m) while satisfying an initial mass in low Earth orbit (IMLEO) limit of ˜60 t (3 SSTO launches). Using ˜8 t of LUNOX to ``reoxidize'' the LERV for a ``direct return'' flight to Earth reduces its size and mass allowing delivery to LEO on a single 20 t SSTO launch. Similarly, the LANTR engine's ability to operate at any oxygen/hydrogen mixture ratio from 0 to 7 with high specific impulse (˜940 to 515 s) is exploited to reduce hydrogen tank volume, thereby improving packaging of the LANTR LTV's ``propulsion'' and ``propellant modules''. Expendable and reusable, piloted and cargo missions and vehicle designs are presented along with estimates of LUNOX production required to support the different mission modes.

  6. Integration of regenerative shock absorber into vehicle electric system

    Science.gov (United States)

    Zhang, Chongxiao; Li, Peng; Xing, Shaoxu; Kim, Junyoung; Yu, Liangyao; Zuo, Lei

    2014-03-01

    Regenerative/Energy harvesting shock absorbers have a great potential to increase fuel efficiency and provide suspension damping simultaneously. In recent years there's intensive work on this topic, but most researches focus on electricity extraction from vibration and harvesting efficiency improvement. The integration of electricity generated from regenerative shock absorbers into vehicle electric system, which is very important to realize the fuel efficiency benefit, has not been investigated. This paper is to study and demonstrate the integration of regenerative shock absorber with vehicle alternator, battery and in-vehicle electrical load together. In the presented system, the shock absorber is excited by a shaker and it converts kinetic energy into electricity. The harvested electricity flows into a DC/DC converter which realizes two functions: controlling the shock absorber's damping and regulating the output voltage. The damping is tuned by controlling shock absorber's output current, which is also the input current of DC/DC converter. By adjusting the duty cycles of switches in the converter, its input impedance together with input current can be adjusted according to dynamic damping requirements. An automotive lead-acid battery is charged by the DC/DC converter's output. To simulate the working condition of combustion engine, an AC motor is used to drive a truck alternator, which also charges the battery. Power resistors are used as battery's electrical load to simulate in-vehicle electrical devices. Experimental results show that the proposed integration strategy can effectively utilize the harvested electricity and power consumption of the AC motor is decreased accordingly. This proves the combustion engine's load reduction and fuel efficiency improvement.

  7. Advanced Range Safety System for High Energy Vehicles

    Science.gov (United States)

    Claxton, Jeffrey S.; Linton, Donald F.

    2002-01-01

    The advanced range safety system project is a collaboration between the National Aeronautics and Space Administration and the United States Air Force to develop systems that would reduce costs and schedule for safety approval for new classes of unmanned high-energy vehicles. The mission-planning feature for this system would yield flight profiles that satisfy the mission requirements for the user while providing an increased quality of risk assessment, enhancing public safety. By improving the speed and accuracy of predicting risks to the public, mission planners would be able to expand flight envelopes significantly. Once in place, this system is expected to offer the flexibility of handling real-time risk management for the high-energy capabilities of hypersonic vehicles including autonomous return-from-orbit vehicles and extended flight profiles over land. Users of this system would include mission planners of Space Launch Initiative vehicles, space planes, and other high-energy vehicles. The real-time features of the system could make extended flight of a malfunctioning vehicle possible, in lieu of an immediate terminate decision. With this improved capability, the user would have more time for anomaly resolution and potential recovery of a malfunctioning vehicle.

  8. Novel Aerodynamic Design for Formula SAE Vehicles

    Science.gov (United States)

    Sentongo, Samuel; Carter, Austin; Cecil, Christopher; Feier, Ioan

    2017-11-01

    This paper identifies and evaluates the design characteristics of a novel airfoil that harnesses the Magnus Effect, applying a moving-surface boundary-layer control (MSBC) method to a Formula SAE Vehicle. The MSBC minimizes adverse pressure gradient and delays boundary layer separation through the use of a conveyor belt that interacts with the airfoil boundary layer. The MSBC allows dynamic control of the aerodynamic coefficients by variation of the belt speed, minimizing drag in high speed straights and maximizing downforce during vehicle cornering. A conveyer belt wing measuring approximately 0.9 x 0.9m in planform was designed and built to test the mechanical setup for such a MSBC wing. This study follows the relationship between inputted power and outputted surface velocity, with the goal being to maximize speed output vs. power input. The greatest hindrance to maximizing speed output is friction among belts, rollers, and stationary members. The maximum belt speed achieved during testing was 5.9 m/s with a power input of 48.8 W, which corresponds to 45.8 N of downforce based on 2D CFD results. Ongoing progress on this project is presented. United States Air Force Academy.

  9. A particle filter for ammonia coverage ratio and input simultaneous estimations in Diesel-engine SCR system.

    Science.gov (United States)

    Sun, Kangfeng; Ji, Fenzhu; Yan, Xiaoyu; Jiang, Kai; Yang, Shichun

    2018-01-01

    As NOx emissions legislation for Diesel-engines is becoming more stringent than ever before, an aftertreatment system has been widely used in many countries. Specifically, to reduce the NOx emissions, a selective catalytic reduction(SCR) system has become one of the most promising techniques for Diesel-engine vehicle applications. In the SCR system, input ammonia concentration and ammonia coverage ratio are regarded as essential states in the control-oriental model. Currently, an ammonia sensor placed before the SCR Can is a good strategy for the input ammonia concentration value. However, physical sensor would increase the SCR system cost and the ammonia coverage ratio information cannot be directly measured by physical sensor. Aiming to tackle this problem, an observer based on particle filter(PF) is investigated to estimate the input ammonia concentration and ammonia coverage ratio. Simulation results through the experimentally-validated full vehicle simulator cX-Emission show that the performance of observer based on PF is outstanding, and the estimation error is very small.

  10. Life Science on the International Space Station Using the Next Generation of Cargo Vehicles

    Science.gov (United States)

    Robinson, J. A.; Phillion, J. P.; Hart, A. T.; Comella, J.; Edeen, M.; Ruttley, T. M.

    2011-01-01

    With the retirement of the Space Shuttle and the transition of the International Space Station (ISS) from assembly to full laboratory capabilities, the opportunity to perform life science research in space has increased dramatically, while the operational considerations associated with transportation of the experiments has changed dramatically. US researchers have allocations on the European Automated Transfer Vehicle (ATV) and Japanese H-II Transfer Vehicle (HTV). In addition, the International Space Station (ISS) Cargo Resupply Services (CRS) contract will provide consumables and payloads to and from the ISS via the unmanned SpaceX (offers launch and return capabilities) and Orbital (offers only launch capabilities) resupply vehicles. Early requirements drove the capabilities of the vehicle providers; however, many other engineering considerations affect the actual design and operations plans. To better enable the use of the International Space Station as a National Laboratory, ground and on-orbit facility development can augment the vehicle capabilities to better support needs for cell biology, animal research, and conditioned sample return. NASA Life scientists with experience launching research on the space shuttle can find the trades between the capabilities of the many different vehicles to be confusing. In this presentation we will summarize vehicle and associated ground processing capabilities as well as key concepts of operations for different types of life sciences research being launched in the cargo vehicles. We will provide the latest status of vehicle capabilities and support hardware and facilities development being made to enable the broadest implementation of life sciences research on the ISS.

  11. Dr. von Braun With a Model of a Launch Vehicle

    Science.gov (United States)

    1950-01-01

    Dr. von Braun stands beside a model of the upper stage (Earth-returnable stage) of the three-stage launch vehicle built for the series of the motion picture productions of space flight produced by Walt Disney in the mid-1950's.

  12. Vehicle Velocity and Roll Angle Estimation with Road and Friction Adaptation for Four-Wheel Independent Drive Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Linhui Zhao

    2014-01-01

    Full Text Available Vehicle velocity and roll angle are important information for active safety control systems of four-wheel independent drive electric vehicle. In order to obtain robustness estimation of vehicle velocity and roll angle, a novel method is proposed based on vehicle dynamics and the measurement information provided by the sensors equipped in modern cars. The method is robust with respect to different road and friction conditions. Firstly, the dynamic characteristics of four-wheel independent drive electric vehicle are analyzed, and a four-degree-of-freedom nonlinear dynamic model of vehicle and a tire longitudinal dynamic equation are established. The relationship between the longitudinal and lateral friction forces is derived based on Dugoff tire model. The unknown input reconstruction technique of sliding mode observer is used to achieve longitudinal tire friction force estimation. A simple observer is designed for the estimation of the roll angle of the vehicle. And then using the relationship, the estimated longitudinal friction forces and roll angle, a sliding mode observer for vehicle velocity estimation is provided, which does not need to know the tire-road friction coefficient and road angles. Finally, the proposed method is evaluated experimentally under a variety of maneuvers and road conditions.

  13. Locating Depots for Capacitated Vehicle Routing

    DEFF Research Database (Denmark)

    Gørtz, Inge Li; Nagarajan, Viswanath

    2011-01-01

    that all demands are satisfied and the total cost is minimized. Our main result is a constant-factor approximation algorithm for k-LocVRP. To achieve this result, we reduce k-LocVRP to the following generalization of k median, which might be of independent interest. Given a metric (V, d), bound k...... median forest, which leads to a (12+E)-approximation algorithm for k-LocVRP, for any constant E > 0. The algorithm for k median forest is t-swap local search, and we prove that it has locality gap 3 + 2 t ; this generalizes the corresponding result for k median [3]. Finally we consider the k median......We study a location-routing problem in the context of capacitated vehicle routing. The input to k-LocVRP is a set of demand locations in a metric space and a fleet of k vehicles each of capacity Q. The objective is to locate k depots, one for each vehicle, and compute routes for the vehicles so...

  14. Fund allocation using capacitated vehicle routing problem

    Science.gov (United States)

    Mamat, Nur Jumaadzan Zaleha; Jaaman, Saiful Hafizah; Ahmad, Rokiah Rozita; Darus, Maslina

    2014-09-01

    In investment fund allocation, it is unwise for an investor to distribute his fund into several assets simultaneously due to economic reasons. One solution is to allocate the fund into a particular asset at a time in a sequence that will either maximize returns or minimize risks depending on the investor's objective. The vehicle routing problem (VRP) provides an avenue to this issue. VRP answers the question on how to efficiently use the available fleet of vehicles to meet a given service demand, subjected to a set of operational requirements. This paper proposes an idea of using capacitated vehicle routing problem (CVRP) to optimize investment fund allocation by employing data of selected stocks in the FTSE Bursa Malaysia. Results suggest that CRVP can be applied to solve the issue of investment fund allocation and increase the investor's profit.

  15. Genesis of the Lunar Landing Vehicle

    Science.gov (United States)

    Gelzer, Christian

    2009-01-01

    The author examines early research regarding return flight from a Moon landing made prior to President Kennedy's 1961 challenge to put men on the Moon before the end of the decade. Organizations involved in early research include NACA, the Flight Research Center (now Dryden) Bell Aircraft Corporation. The discussion focuses on development of a flight simulator to model the Moon's reduced gravity and development of the Lunar Landing Research Vehicle.

  16. Improved heavy-duty vehicle fuel efficiency in India, benefits, costs and environmental impacts

    Energy Technology Data Exchange (ETDEWEB)

    Gopal, Anand R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Karali, Nihan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sharpe, Ben [International Council on Clean Transportation (United States); Delgado, Oscar [International Council on Clean Transportation (United States); Bandivadekar, Anup [International Council on Clean Transportation (United States); Garg, Mehul [International Council on Clean Transportation (United States)

    2017-06-14

    The main objectives of this analysis are to examine the benefits and costs of fuel-saving technologies for new heavy-duty vehicles (HDVs) in India over the next 10 years and, to explore how various scenarios for the deployment of vehicles with these technologies will impact petroleum consumption and carbon dioxide (CO2) emissions over the next three decades. The study team developed simulation models for three representative HDV types—a 40-tonne tractor-trailer, 25-tonne rigid truck, and 16-tonne transit bus—based on top-selling vehicle models in the Indian market. The baseline technology profiles for all three vehicles were developed using India-specific engine data and vehicle specification information from manufacturer literature and input from industry experts. For each of the three vehicles we developed a comprehensive set of seven efficiency technology packages drawing from five major areas: engine, transmission and driveline, tires, aerodynamics, and weight reduction. Our analysis finds that India has substantial opportunity to improve HDV fuel efficiency levels using cost-effective technologies. Results from our simulation modeling of three representative HDV types—a tractor-trailer, rigid truck, and transit bus—reveal that per-vehicle fuel consumption reductions between roughly 20% and 35% are possible with technologies that provide a return on the initial capital investment within 1 to 2 years. Though most of these technologies are currently unavailable in India, experiences in other more advanced markets such as the US and EU suggest that with sufficient incentives and robust regulatory design, significant progress can be made in developing and deploying efficiency technologies that can provide real-world fuel savings for new commercial vehicles in India over the next 10 years. Bringing HDVs in India up to world-class technology levels will yield substantial petroleum and GHG reductions. By 2030, the fuel and CO2 reductions of the

  17. The potential of electric vehicles

    International Nuclear Information System (INIS)

    2016-04-01

    Electric vehicles can help reduce the dependence of road transport on imported oil, cut the country's energy bill, reduce greenhouse gas emissions, improve air quality in cities through zero exhaust emissions and reduce noise pollution. The economic costs and environmental impacts of electric vehicles are mostly concentrated at the manufacturing stage, whereas the costs and impacts of internal combustion vehicles are predominantly felt during usage. So we cannot simply compare vehicles as objects, we must see how they are used, which means taking a fresh look at the full potential of electric vehicles which must be used intensely to be economically and environmentally viable. The main advantage of internal combustion vehicles is their ability to carry a very large amount of energy giving them a very large range and significant versatility. However, the consequences of the use of fossil fuels on the climate and the environment today require us to look for other solutions for vehicles and mobility systems. Electric vehicles are among these: its lack of versatility, due to its still limited range, is offset by being more adaptable and optimised for the usage sought. Electric vehicles are particularly suitable for new mobility services offerings and allow the transition to new ways of travelling to be speeded up optimising the use of the vehicle and no longer requiring ownership of it. The use of digital, facilitated by the electrical engine, opens up numerous opportunities for innovations and new services (such as the autonomous vehicle for example). In addition, electric vehicles can do more than just transport. Their batteries provide useful energy storage capabilities that can help regulate the power grid and the development of renewable energy. The marketing of electric vehicles may be accompanied by energy services that can be economically viable and used to structure the electro-mobility offer in return. To minimise the impact on the electrical grid, it is

  18. A polynomial chaos approach to the analysis of vehicle dynamics under uncertainty

    Science.gov (United States)

    Kewlani, Gaurav; Crawford, Justin; Iagnemma, Karl

    2012-05-01

    The ability of ground vehicles to quickly and accurately analyse their dynamic response to a given input is critical to their safety and efficient autonomous operation. In field conditions, significant uncertainty is associated with terrain and/or vehicle parameter estimates, and this uncertainty must be considered in the analysis of vehicle motion dynamics. Here, polynomial chaos approaches that explicitly consider parametric uncertainty during modelling of vehicle dynamics are presented. They are shown to be computationally more efficient than the standard Monte Carlo scheme, and experimental results compared with the simulation results performed on ANVEL (a vehicle simulator) indicate that the method can be utilised for efficient and accurate prediction of vehicle motion in realistic scenarios.

  19. Aerospace Vehicle Design, Spacecraft Section. Final Project Reports. Volume 2; Project Groups 6-8

    Science.gov (United States)

    1989-01-01

    Three groups of student engineers in an aerospace vehicle design course present their designs for a vehicle that can be used to resupply the Space Station Freedam and provide emergency crew return to earth capability. The vehicle's requirements include a lifetime that exceeds six years, low cost, the capability for withstanding pressurization, launch, orbit, and reentry hazards, and reliability. The vehicle's subsystems are structures, communication and command data systems, attitude and articulation control, life support and crew systems, power and propulsion, reentry and recovery systems, and mission management, planning, and costing. Special attention is given to spacecraft communications.

  20. Anti-Windup Control for an Air-Breathing Hypersonic Vehicle Model

    National Research Council Canada - National Science Library

    Groves, Kevin P; Serrani, Andrea; Yurkovich, Stephen; Bolender, Michael A; Doman, David B

    2005-01-01

    .... Anti-windup control allows the input constraints to be considered explicitly in the design of linear controllers to track a reference trajectory for the vehicle velocity, altitude, and angle of attack...

  1. What Fleets Need to Know About Alternative Fuel Vehicle Conversions, Retrofits, and Repowers

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, K.; Gonzales, J.

    2017-10-02

    Many fleet managers have opted to incorporate alternative fuels and advanced vehicles into their lineup. Original equipment manufacturers (OEMs) offer a variety of choices, and there are additional options offered by aftermarket companies. There are also a myriad of ways that existing vehicles can be modified to utilize alternative fuels and other advanced technologies. Vehicle conversions and retrofit packages, along with engine repower options, can offer an ideal way to lower vehicle operating costs. This can result in long term return on investment, in addition to helping fleet managers achieve emissions and environmental goals. This report summarizes the various factors to consider when pursuing a conversion, retrofit, or repower option.

  2. What Fleets Need to Know About Alternative Fuel Vehicle Conversions, Retrofits, and Repowers

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Kay L. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gonzales, John [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-10-17

    Many fleet managers have opted to incorporate alternative fuels and advanced vehicles into their lineup. Original equipment manufacturers (OEMs) offer a variety of choices, and there are additional options offered by aftermarket companies. There are also a myriad of ways that existing vehicles can be modified to utilize alternative fuels and other advanced technologies. Vehicle conversions and retrofit packages, along with engine repower options, can offer an ideal way to lower vehicle operating costs. This can result in long term return on investment, in addition to helping fleet managers achieve emissions and environmental goals. This report summarizes the various factors to consider when pursuing a conversion, retrofit, or repower option.

  3. Cooperative Path-Planning for Multi-Vehicle Systems

    Directory of Open Access Journals (Sweden)

    Qichen Wang

    2014-11-01

    Full Text Available In this paper, we propose a collision avoidance algorithm for multi-vehicle systems, which is a common problem in many areas, including navigation and robotics. In dynamic environments, vehicles may become involved in potential collisions with each other, particularly when the vehicle density is high and the direction of travel is unrestricted. Cooperatively planning vehicle movement can effectively reduce and fairly distribute the detour inconvenience before subsequently returning vehicles to their intended paths. We present a novel method of cooperative path planning for multi-vehicle systems based on reinforcement learning to address this problem as a decision process. A dynamic system is described as a multi-dimensional space formed by vectors as states to represent all participating vehicles’ position and orientation, whilst considering the kinematic constraints of the vehicles. Actions are defined for the system to transit from one state to another. In order to select appropriate actions whilst satisfying the constraints of path smoothness, constant speed and complying with a minimum distance between vehicles, an approximate value function is iteratively developed to indicate the desirability of every state-action pair from the continuous state space and action space. The proposed scheme comprises two phases. The convergence of the value function takes place in the former learning phase, and it is then used as a path planning guideline in the subsequent action phase. This paper summarizes the concept and methodologies used to implement this online cooperative collision avoidance algorithm and presents results and analysis regarding how this cooperative scheme improves upon two baseline schemes where vehicles make movement decisions independently.

  4. Vision-Aided Autonomous Landing and Ingress of Micro Aerial Vehicles

    Science.gov (United States)

    Brockers, Roland; Ma, Jeremy C.; Matthies, Larry H.; Bouffard, Patrick

    2012-01-01

    Micro aerial vehicles have limited sensor suites and computational power. For reconnaissance tasks and to conserve energy, these systems need the ability to autonomously land at vantage points or enter buildings (ingress). But for autonomous navigation, information is needed to identify and guide the vehicle to the target. Vision algorithms can provide egomotion estimation and target detection using input from cameras that are easy to include in miniature systems.

  5. Stochastic long term modelling of a drainage system with estimation of return period uncertainty

    DEFF Research Database (Denmark)

    Thorndahl, Søren

    2009-01-01

    Long term prediction of maximum water levels and combined sewer overflow (CSO) in drainage systems are associated with large uncertainties. Especially on rainfall inputs, parameters, and assessment of return periods. This paper proposes a Monte Carlo based methodology for stochastic prediction of...

  6. A design approach for small vision-based autonomous vehicles

    Science.gov (United States)

    Edwards, Barrett B.; Fife, Wade S.; Archibald, James K.; Lee, Dah-Jye; Wilde, Doran K.

    2006-10-01

    This paper describes the design of a small autonomous vehicle based on the Helios computing platform, a custom FPGA-based board capable of supporting on-board vision. Target applications for the Helios computing platform are those that require lightweight equipment and low power consumption. To demonstrate the capabilities of FPGAs in real-time control of autonomous vehicles, a 16 inch long R/C monster truck was outfitted with a Helios board. The platform provided by such a small vehicle is ideal for testing and development. The proof of concept application for this autonomous vehicle was a timed race through an environment with obstacles. Given the size restrictions of the vehicle and its operating environment, the only feasible on-board sensor is a small CMOS camera. The single video feed is therefore the only source of information from the surrounding environment. The image is then segmented and processed by custom logic in the FPGA that also controls direction and speed of the vehicle based on visual input.

  7. Return to work helps maintain treatment gains in the rehabilitation of whiplash injury.

    Science.gov (United States)

    Sullivan, Michael; Adams, Heather; Thibault, Pascal; Moore, Emily; Carriere, Junie S; Larivière, Christian

    2017-05-01

    This study examined the relation between return to work and the maintenance of treatment gains made over the course of a rehabilitation intervention. The study sample consisted of 110 individuals who had sustained whiplash injuries in rear collision motor vehicle accidents and were work-disabled at the time of enrolment in the study. Participants completed pre- and post-treatment measures of pain severity, disability, cervical range of motion, depression, posttraumatic stress symptoms, and catastrophizing. Pain severity was assessed again at 1-year follow-up. At 1-year follow-up, 73 participants had returned to work and 37 remained work-disabled. Analyses revealed that participants who returned to work were more likely to maintain treatment gains (77.5%) than participants who remained work-disabled (48%), χ = 6.3, P whiplash injury are maintained. Clinical implications of the findings are also addressed.

  8. 2009 DOE Vehicle Technologies Program Annual Merit Review

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2009-10-01

    Annual Merit Review and Peer Evaluation Meeting to review the FY2008 accomplishments and FY2009 plans for the Vehicle Technologies Program, and provide an opportunity for industry, government, and academic to give inputs to DOE on the Program with a structured and formal methodology.

  9. Robust on-off pulse control of flexible space vehicles

    Science.gov (United States)

    Wie, Bong; Sinha, Ravi

    1993-01-01

    The on-off reaction jet control system is often used for attitude and orbital maneuvering of various spacecraft. Future space vehicles such as the orbital transfer vehicles, orbital maneuvering vehicles, and space station will extensively use reaction jets for orbital maneuvering and attitude stabilization. The proposed robust fuel- and time-optimal control algorithm is used for a three-mass spacing model of flexible spacecraft. A fuel-efficient on-off control logic is developed for robust rest-to-rest maneuver of a flexible vehicle with minimum excitation of structural modes. The first part of this report is concerned with the problem of selecting a proper pair of jets for practical trade-offs among the maneuvering time, fuel consumption, structural mode excitation, and performance robustness. A time-optimal control problem subject to parameter robustness constraints is formulated and solved. The second part of this report deals with obtaining parameter insensitive fuel- and time- optimal control inputs by solving a constrained optimization problem subject to robustness constraints. It is shown that sensitivity to modeling errors can be significantly reduced by the proposed, robustified open-loop control approach. The final part of this report deals with sliding mode control design for uncertain flexible structures. The benchmark problem of a flexible structure is used as an example for the feedback sliding mode controller design with bounded control inputs and robustness to parameter variations is investigated.

  10. A Comprehensive Structural Dynamic Analysis Approach for Multi Mission Earth Entry Vehicle (MMEEV) Development

    Science.gov (United States)

    Perino, Scott; Bayandor, Javid; Siddens, Aaron

    2012-01-01

    The anticipated NASA Mars Sample Return Mission (MSR) requires a simple and reliable method in which to return collected Martian samples back to earth for scientific analysis. The Multi-Mission Earth Entry Vehicle (MMEEV) is NASA's proposed solution to this MSR requirement. Key aspects of the MMEEV are its reliable and passive operation, energy absorbing foam-composite structure, and modular impact sphere (IS) design. To aid in the development of an EEV design that can be modified for various missions requirements, two fully parametric finite element models were developed. The first model was developed in an explicit finite element code and was designed to evaluate the impact response of the vehicle and payload during the final stage of the vehicle's return to earth. The second model was developed in an explicit code and was designed to evaluate the static and dynamic structural response of the vehicle during launch and reentry. In contrast to most other FE models, built through a Graphical User Interface (GUI) pre-processor, the current model was developed using a coding technique that allows the analyst to quickly change nearly all aspects of the model including: geometric dimensions, material properties, load and boundary conditions, mesh properties, and analysis controls. Using the developed design tool, a full range of proposed designs can quickly be analyzed numerically and thus the design trade space for the EEV can be fully understood. An engineer can then quickly reach the best design for a specific mission and also adapt and optimize the general design for different missions.

  11. Optimizing investment fund allocation using vehicle routing problem framework

    Science.gov (United States)

    Mamat, Nur Jumaadzan Zaleha; Jaaman, Saiful Hafizah; Ahmad, Rokiah Rozita

    2014-07-01

    The objective of investment is to maximize total returns or minimize total risks. To determine the optimum order of investment, vehicle routing problem method is used. The method which is widely used in the field of resource distribution shares almost similar characteristics with the problem of investment fund allocation. In this paper we describe and elucidate the concept of using vehicle routing problem framework in optimizing the allocation of investment fund. To better illustrate these similarities, sectorial data from FTSE Bursa Malaysia is used. Results show that different values of utility for risk-averse investors generate the same investment routes.

  12. RISK AND RETURN IN THE REAL ESTATE, BOND AND STOCK MARKETS

    Directory of Open Access Journals (Sweden)

    Wolski Rafał

    2017-09-01

    Full Text Available Studies investigating the relation between risk and return occupy an important place in the discussion about the effectiveness of investing in real estate. A review of the available studies shows that real estate investments are less profitable than stocks, but in terms of risk and return, are usually the best option. This worldwide regularity may not necessarily be presented in Poland, as the Polish market is not fully fledged yet. The analysis presented in this article was performed with a view to reducing a research gap resulting from the lack of comprehensive Polish studies in this field. In the article, data spanning the years from 2006 to 2016 are examined by means of descriptive statistics, measures of risk, and the analysis of variance (ANOVA to determine which of the following investment vehicles - bonds, real estate or stocks - offer the best risk-return ratio. The article has two parts. The analytical part is a review of studies on risk measurement methods and of earlier studies investigating risk and return by a class of assets (particularly real estate. In the empirical part, assets are compared with the use of statistical methods. The results of the risk-return analysis point to the money market as the best option for investors. Stocks and real estate ranked second and third, respectively.

  13. Discrete Optimization Model for Vehicle Routing Problem with Scheduling Side Cosntraints

    Science.gov (United States)

    Juliandri, Dedy; Mawengkang, Herman; Bu'ulolo, F.

    2018-01-01

    Vehicle Routing Problem (VRP) is an important element of many logistic systems which involve routing and scheduling of vehicles from a depot to a set of customers node. This is a hard combinatorial optimization problem with the objective to find an optimal set of routes used by a fleet of vehicles to serve the demands a set of customers It is required that these vehicles return to the depot after serving customers’ demand. The problem incorporates time windows, fleet and driver scheduling, pick-up and delivery in the planning horizon. The goal is to determine the scheduling of fleet and driver and routing policies of the vehicles. The objective is to minimize the overall costs of all routes over the planning horizon. We model the problem as a linear mixed integer program. We develop a combination of heuristics and exact method for solving the model.

  14. Symptomatic cervical disc herniation following a motor vehicle collision: return to work comparative study of workers' compensation versus personal injury insurance status.

    Science.gov (United States)

    Scuderi, Gaetano J; Sherman, Andrew L; Brusovanik, Georgiy V; Pahl, Michael A; Vaccaro, Alexander R

    2005-01-01

    Patients with approved workers' compensation injuries receive guaranteed compensation for the duration of their injury, whereas patients with personal injury claims are only compensated, if at all, at the time of a successful settlement or trial verdict at a time point distant from their injury. This study compares the financial impact and loss of work patterns due to a workers' compensation (WC) claim or personal injury in patients with a symptomatic cervical disc herniation resulting from a motor vehicle collision. A prospective study of patients who were seen by a single spine specialist between 1/2/96 and 9/1/01. A consecutive evaluation of 531 patients who were treated for a cervical pain syndrome caused by a motor vehicle collision. Mechanism of injury and insurance type, ie, workers' compensation or personal injury, was recorded for each patient as well as treatment response and return to work patterns. The data were analyzed using the two-way Z test. All patients were managed in a similar manner with noninvasive treatment initially, followed by injections, and finally surgical intervention in those who failed conservative measures. Return to work rates and work disability were determined at either final follow-up or at the last doctor's visit before loss to follow-up. 270 of 531 patients were diagnosed with a symptomatic one or two level disc herniation by a cervical magnetic resonance imaging scan. Fifty-four patients were insured through the workers' compensation board, and 216 reported their crash as a personal injury claim. In the WC group the work disability at 3 months follow-up revealed a cumulative 2,262 total lost days of work (average 37.1 days per person). At the point of maximal medical improvement (MMI) or 2-year follow-up, total days lost from work were 7,107 (average 131.6 days per person.) In the personal injury non-WC group, the 3-month follow-up of lost days of work was 1,093 days (average 5.1 days per person.) At 2 years follow-up, the

  15. EDIN0613P weight estimating program. [for launch vehicles

    Science.gov (United States)

    Hirsch, G. N.

    1976-01-01

    The weight estimating relationships and program developed for space power system simulation are described. The program was developed to size a two-stage launch vehicle for the space power system. The program is actually part of an overall simulation technique called EDIN (Engineering Design and Integration) system. The program sizes the overall vehicle, generates major component weights and derives a large amount of overall vehicle geometry. The program is written in FORTRAN V and is designed for use on the Univac Exec 8 (1110). By utilizing the flexibility of this program while remaining cognizant of the limits imposed upon output depth and accuracy by utilization of generalized input, this program concept can be a useful tool for estimating purposes at the conceptual design stage of a launch vehicle.

  16. The Study of Road Conditions that Affect Tilt-based Text Input for Mobile Devices

    Directory of Open Access Journals (Sweden)

    Darius Miniotas

    2017-07-01

    Full Text Available With the rapid advances in technology of mobile devices, their application areas expand continuously as well. Given the growth of the market share for mobile devices, one of the main issues that arise is the need for new and convenient techniques for data input and output suitable for various settings. Tilt-based text input is one of the alternatives that attract attention of current researchers. This study investigates the potential of using tilt-based interaction to enter text while sitting as a passenger in a moving vehicle. In addition, the investigation focused on the characteristics of the road as well as driving conditions that affect tilt-based text input. The study manipulated the following factors: keyboard size 10×4 and road unevenness (small, moderate, and large. 14 participants, aged 25 to 50, took part in the user study. The best performance and the shortest task completion time equal to 24.5 seconds was observed when the vehicle was moving at a constant speed on a straight road with small unevenness. The task completion time increased by 15% in moderate unevenness road and by almost 20 % in large unevenness road. Error rate and movement efficiency were investigated additionally in order to find out the cause of such times.

  17. Lessons Learned: Mechanical Component and Tribology Activities in Support of Return to Flight

    Science.gov (United States)

    Handschuh, Robert F.; Zaretsky, Erwin V.

    2017-01-01

    The February 2003 loss of the Space Shuttle Columbia resulted in NASA Management revisiting every critical system onboard this very complex, reusable space vehicle in a an effort to Return to Flight. Many months after the disaster, contact between NASA Johnson Space Center and NASA Glenn Research Center evolved into an in-depth assessment of the actuator drive systems for the Rudder Speed Brake and Body Flap Systems. The actuators are CRIT 1-1 systems that classifies them as failure of any of the actuators could result in loss of crew and vehicle. Upon further evaluation of these actuator systems and the resulting issues uncovered, several research activities were initiated, conducted, and reported to the NASA Space Shuttle Program Management. The papers contained in this document are the contributions of many researchers from NASA Glenn Research Center and Marshall Space Flight Center as part of a Lessons Learned on mechanical actuation systems as used in space applications. Many of the findings contained in this document were used as a basis to safely Return to Flight for the remaining Space Shuttle Fleet until their retirement.

  18. Optimization of vehicle weight for Mars excursion missions

    Science.gov (United States)

    Ferebee, Melvin J., Jr.

    1991-01-01

    The excursion class mission to Mars is defined as a mission with one year durations coupled with a stay time of up to 30 days. The fuel budget for such a mission is investigated. The overall figure of merit in such an assessment is the vehicle weight ratio, the ratio between the wet vehicle weight to the dry vehicle weight. It is necessary to minimize the overall fuel budget for the mission in order to maximize the benefits that could be obtained by sending humans to Mars. Assumptions used in the analysis are: each mission will depart and terminate in low-earth-orbit (LEO) (500 km circular) and the maximum stay time at Mars is 30 days. The maximum mission duration is one year (355-375 days). The mass returned to LEO is 135,000 kg, the dropoff mass left at Mars is 168,000 kg. Three propulsive techniques for atmospheric interface are investigated: aerobraking, all-chemical propulsion, and nuclear thermal propulsion. By defining the fuel requirements, the space transfer vehicle's configuration is defined.

  19. Hydrodynamic Coefficients Identification and Experimental Investigation for an Underwater Vehicle

    Directory of Open Access Journals (Sweden)

    Shaorong XIE

    2014-02-01

    Full Text Available Hydrodynamic coefficients are the foundation of unmanned underwater vehicles modeling and controller design. In order to reduce identification complexity and acquire necessary hydrodynamic coefficients for controllers design, the motion of the unmanned underwater vehicle was separated into vertical motion and horizontal motion models. Hydrodynamic coefficients were regarded as mapping parameters from input forces and moments to output velocities and acceleration of the unmanned underwater vehicle. The motion models of the unmanned underwater vehicle were nonlinear and Genetic Algorithm was adopted to identify those hydrodynamic coefficients. To verify the identification quality, velocities and acceleration of the unmanned underwater vehicle was measured using inertial sensor under the same conditions as Genetic Algorithm identification. Curves similarity between measured velocities and acceleration and those identified by Genetic Algorithm were used as optimizing standard. It is found that the curves similarity were high and identified hydrodynamic coefficients of the unmanned underwater vehicle satisfied the measured motion states well.

  20. A study on optimization of hybrid drive train using Advanced Vehicle Simulator (ADVISOR)

    Energy Technology Data Exchange (ETDEWEB)

    Same, Adam; Stipe, Alex; Grossman, David; Park, Jae Wan [Department of Mechanical and Aeronautical Engineering, University of California, Davis, One Shields Ave, Davis, CA 95616 (United States)

    2010-10-01

    This study investigates the advantages and disadvantages of three hybrid drive train configurations: series, parallel, and ''through-the-ground'' parallel. Power flow simulations are conducted with the MATLAB/Simulink-based software ADVISOR. These simulations are then applied in an application for the UC Davis SAE Formula Hybrid vehicle. ADVISOR performs simulation calculations for vehicle position using a combined backward/forward method. These simulations are used to study how efficiency and agility are affected by the motor, fuel converter, and hybrid configuration. Three different vehicle models are developed to optimize the drive train of a vehicle for three stages of the SAE Formula Hybrid competition: autocross, endurance, and acceleration. Input cycles are created based on rough estimates of track geometry. The output from these ADVISOR simulations is a series of plots of velocity profile and energy storage State of Charge that provide a good estimate of how the Formula Hybrid vehicle will perform on the given course. The most noticeable discrepancy between the input cycle and the actual velocity profile of the vehicle occurs during deceleration. A weighted ranking system is developed to organize the simulation results and to determine the best drive train configuration for the Formula Hybrid vehicle. Results show that the through-the-ground parallel configuration with front-mounted motors achieves an optimal balance of efficiency, simplicity, and cost. ADVISOR is proven to be a useful tool for vehicle power train design for the SAE Formula Hybrid competition. This vehicle model based on ADVISOR simulation is applicable to various studies concerning performance and efficiency of hybrid drive trains. (author)

  1. The Optimal Steering Control System using Imperialist Competitive Algorithm on Vehicles with Steer-by-Wire System

    Directory of Open Access Journals (Sweden)

    F. Hunaini

    2015-03-01

    Full Text Available Steer-by-wire is the electrical steering systems on vehicles that are expected with the development of an optimal control system can improve the dynamic performance of the vehicle. This paper aims to optimize the control systems, namely Fuzzy Logic Control (FLC and the Proportional, Integral and Derivative (PID control on the vehicle steering system using Imperialist Competitive Algorithm (ICA. The control systems are built in a cascade, FLC to suppress errors in the lateral motion and the PID control to minimize the error in the yaw motion of the vehicle. FLC is built has two inputs (error and delta error and single output. Each input and output consists of three Membership Function (MF in the form of a triangular for language term "zero" and two trapezoidal for language term "negative" and "positive". In order to work optimally, each MF optimized using ICA to get the position and width of the most appropriate. Likewise, in the PID control, the constant at each Proportional, Integral and Derivative control also optimized using ICA, so there are six parameters of the control system are simultaneously optimized by ICA. Simulations performed on vehicle models with 10 Degree Of Freedom (DOF, the plant input using the variables of steering that expressed in the desired trajectory, and the plant outputs are lateral and yaw motion. The simulation results showed that the FLC-PID control system optimized by using ICA can maintain the movement of vehicle according to the desired trajectory with lower error and higher speed limits than optimized with Particle Swarm Optimization (PSO.

  2. Damage assessment methodology for vehicles exposed to flooding in urban areas

    Directory of Open Access Journals (Sweden)

    E. Martínez Gomariz

    2017-10-01

    Full Text Available Urban floods may provoke important damages to vehicles, usually not taken into account within most studies related to urban flood risks damage assessments. Herein a methodology to estimate damages to vehicles exposed to urban floods is presented. After a state-of-the-art review, the most recent damage curves for vehicles developed by the U.S. Army Corps of Engineers (USACE, 2009 are presented as the best adaptive and the most comprehensively performed so far. The proposed methodology is applied to the Spanish municipality of Badalona, framed in the H2020 European Project BINGO. In order to conduct this methodology some aspects such as the vehicular distribution are analyzed within the study area. Finally, Expected Annual Damage (EAD for flooded vehicles is calculated based on inundations related to design storms of different return periods (1, 10, 100 and 500 years.

  3. A Storable, Hybrid Mars Ascent Vehicle Technology Demonstrator for the 2020 Launch Opportunity

    Science.gov (United States)

    Chandler, A. A.; Karabeyoglu, M. A.; Cantwell, B. J.; Reeve, R.; Goldstein, B. G.; Hubbard, G. S.

    2012-06-01

    A Phoenix sized mission including a reduced payload, two-stage, hybrid Mars Ascent Vehicle technology demonstrator is proposed for the 2020 opportunity. The hybrid MAV is storable on Mars and would retire risk for a Mars Sample Return campaign.

  4. Control system and method for a hybrid electric vehicle

    Science.gov (United States)

    Tamor, Michael Alan

    2001-03-06

    Several control methods are presented for application in a hybrid electric vehicle powertrain including in various embodiments an engine, a motor/generator, a transmission coupled at an input thereof to receive torque from the engine and the motor generator coupled to augment torque provided by the engine, an energy storage device coupled to receive energy from and provide energy to the motor/generator, an engine controller (EEC) coupled to control the engine, a transmission controller (TCM) coupled to control the transmission and a vehicle system controller (VSC) adapted to control the powertrain.

  5. Design of a multi-vehicles delivery tours satisfying duration constraints

    Energy Technology Data Exchange (ETDEWEB)

    Langevin, A; Soumis, F

    1987-01-01

    The following organization was studied for the letter and parcel pick-up and delivery problem in an urban environment. The day is divided in periods of time in which each vehicle starts from a sorting centre, travels to a very precise area of the region, picks up and delivers letters and parcels, and returns to the depot to have the collected material sorted out for delivery during the following period. The intent of this approach is to have each zone serviced by one vehicle only, in order to facilitate the work of the dispatcher and routing of each vehicle. A method has been developed of partitioning an urban region into zones to be assigned, each one to a specific vehicle, so as to minimize the total number of vehicles used or the total distance travelled by all vehicles. The first part of the method determines the zones and the average number of points to visit. Then, a first refinement of the method takes into account the daily variability of the demand in each zone, whereas a second refinement examines the advantage of allowing some overlapping of zones for the purpose of having an overloaded vehicle relieved by one from an adjacent zone. 17 refs., 11 figs., 2 tabs.

  6. Ares Launch Vehicles Overview: Space Access Society

    Science.gov (United States)

    Cook, Steve

    2007-01-01

    America is returning to the Moon in preparation for the first human footprint on Mars, guided by the U.S. Vision for Space Exploration. This presentation will discuss NASA's mission, the reasons for returning to the Moon and going to Mars, and how NASA will accomplish that mission in ways that promote leadership in space and economic expansion on the new frontier. The primary goals of the Vision for Space Exploration are to finish the International Space Station, retire the Space Shuttle, and build the new spacecraft needed to return people to the Moon and go to Mars. The Vision commits NASA and the nation to an agenda of exploration that also includes robotic exploration and technology development, while building on lessons learned over 50 years of hard-won experience. NASA is building on common hardware, shared knowledge, and unique experience derived from the Apollo Saturn, Space Shuttle, and contemporary commercial launch vehicle programs. The journeys to the Moon and Mars will require a variety of vehicles, including the Ares I Crew Launch Vehicle, which transports the Orion Crew Exploration Vehicle, and the Ares V Cargo Launch Vehicle, which transports the Lunar Surface Access Module. The architecture for the lunar missions will use one launch to ferry the crew into orbit, where it will rendezvous with the Lunar Module in the Earth Departure Stage, which will then propel the combination into lunar orbit. The imperative to explore space with the combination of astronauts and robots will be the impetus for inventions such as solar power and water and waste recycling. This next chapter in NASA's history promises to write the next chapter in American history, as well. It will require this nation to provide the talent to develop tools, machines, materials, processes, technologies, and capabilities that can benefit nearly all aspects of life on Earth. Roles and responsibilities are shared between a nationwide Government and industry team. The Exploration Launch

  7. Mixed Vehicle Flow At Signalized Intersection: Markov Chain Analysis

    Directory of Open Access Journals (Sweden)

    Gertsbakh Ilya B.

    2015-09-01

    Full Text Available We assume that a Poisson flow of vehicles arrives at isolated signalized intersection, and each vehicle, independently of others, represents a random number X of passenger car units (PCU’s. We analyze numerically the stationary distribution of the queue process {Zn}, where Zn is the number of PCU’s in a queue at the beginning of the n-th red phase, n → ∞. We approximate the number Yn of PCU’s arriving during one red-green cycle by a two-parameter Negative Binomial Distribution (NBD. The well-known fact is that {Zn} follow an infinite-state Markov chain. We approximate its stationary distribution using a finite-state Markov chain. We show numerically that there is a strong dependence of the mean queue length E[Zn] in equilibrium on the input distribution of Yn and, in particular, on the ”over dispersion” parameter γ= Var[Yn]/E[Yn]. For Poisson input, γ = 1. γ > 1 indicates presence of heavy-tailed input. In reality it means that a relatively large ”portion” of PCU’s, considerably exceeding the average, may arrive with high probability during one red-green cycle. Empirical formulas are presented for an accurate estimation of mean queue length as a function of load and g of the input flow. Using the Markov chain technique, we analyze the mean ”virtual” delay time for a car which always arrives at the beginning of the red phase.

  8. GOOD NEWS, BAD NEWS AND GARCH EFFECTS IN STOCK RETURN DATA

    OpenAIRE

    Craig A. Depken II

    2001-01-01

    It is shown that the volume of trade can be decomposed into proportional proxies for stochastic flows of good news and bad news into the market. Positive (good) information flows are assumed to increase the price of a financial vehicle while negative (bad) information flows decrease the price. For the majority of a sample of ten split-stocks it is shown that the proposed decomposition explains more GARCH than volume itself. Using the proposed decomposition, the variance of returns for younger...

  9. Advanced transportation system study: Manned launch vehicle concepts for two way transportation system payloads to LEO

    Science.gov (United States)

    Duffy, James B.

    1993-01-01

    The purpose of the Advanced Transportation System Study (ATSS) task area 1 study effort is to examine manned launch vehicle booster concepts and two-way cargo transfer and return vehicle concepts to determine which of the many proposed concepts best meets NASA's needs for two-way transportation to low earth orbit. The study identified specific configurations of the normally unmanned, expendable launch vehicles (such as the National Launch System family) necessary to fly manned payloads. These launch vehicle configurations were then analyzed to determine the integrated booster/spacecraft performance, operations, reliability, and cost characteristics for the payload delivery and return mission. Design impacts to the expendable launch vehicles which would be required to perform the manned payload delivery mission were also identified. These impacts included the implications of applying NASA's man-rating requirements, as well as any mission or payload unique impacts. The booster concepts evaluated included the National Launch System (NLS) family of expendable vehicles and several variations of the NLS reference configurations to deliver larger manned payload concepts (such as the crew logistics vehicle (CLV) proposed by NASA JSC). Advanced, clean sheet concepts such as an F-1A engine derived liquid rocket booster (LRB), the single stage to orbit rocket, and a NASP-derived aerospace plane were also included in the study effort. Existing expendable launch vehicles such as the Titan 4, Ariane 5, Energia, and Proton were also examined. Although several manned payload concepts were considered in the analyses, the reference manned payload was the NASA Langley Research Center's HL-20 version of the personnel launch system (PLS). A scaled up version of the PLS for combined crew/cargo delivery capability, the HL-42 configuration, was also included in the analyses of cargo transfer and return vehicle (CTRV) booster concepts. In addition to strictly manned payloads, two-way cargo

  10. Analysis of vehicle exhaust waste heat recovery potential using a Rankine cycle

    International Nuclear Information System (INIS)

    Domingues, António; Santos, Helder; Costa, Mário

    2013-01-01

    This study evaluates the vehicle exhaust WHR (waste heat recovery) potential using a RC (Rankine cycle ). To this end, both a RC thermodynamic model and a heat exchanger model have been developed. Both models use as input, experimental data obtained from a vehicle tested on a chassis dynamometer. The thermodynamic analysis was performed for water, R123 and R245fa and revealed the advantage of using water as the working fluid in applications of thermal recovery from exhaust gases of vehicles equipped with a spark-ignition engine. Moreover, the heat exchanger effectiveness for the organic working fluids R123 and R245fa is higher than that for the water and, consequently, they can also be considered appropriate for use in vehicle WHR applications through RCs when the exhaust gas temperatures are relatively low. For an ideal heat exchanger, the simulations revealed increases in the internal combustion engine thermal and vehicle mechanical efficiencies of 1.4%–3.52% and 10.16%–15.95%, respectively, while for a shell and tube heat exchanger, the simulations showed an increase of 0.85%–1.2% in the thermal efficiency and an increase of 2.64%–6.96% in the mechanical efficiency for an evaporating pressure of 2 MPa. The results confirm the advantages of using the thermal energy contained in the vehicle exhaust gases through RCs. Furthermore, the present analysis demonstrates that improved evaporator designs and appropriate expander devices allowing for higher evaporating pressures are required to obtain the maximum WHR potential from vehicle RC systems. -- Highlights: ► This study evaluates the vehicle exhaust waste heat recovery potential using Rankine cycle systems. ► A thermodynamic model and a heat exchanger model were developed. ► Experimental data obtained in a vehicle tested on a chassis dynamometer was used as models input. ► Thermodynamic analysis was performed for water, R123 and R245fa. ► Results confirm advantages of using the thermal energy

  11. Modelling vertical uniform contact stress of heavy vehicle tyres

    CSIR Research Space (South Africa)

    Steenkamp, Anton J

    2016-07-01

    Full Text Available over the selected operating range of 25 kN to 45 kN which is the typical load range for heavy vehicle tyres due to legal axle load limits. The polynomial formulas require only the tyre inflation pressure and vertical tyre load as inputs, in order...

  12. SOLVING THE PROBLEM OF VEHICLE ROUTING BY EVOLUTIONARY ALGORITHM

    Directory of Open Access Journals (Sweden)

    Remigiusz Romuald Iwańkowicz

    2016-03-01

    Full Text Available In the presented work the vehicle routing problem is formulated, which concerns planning the collection of wastes by one garbage truck from a certain number of collection points. The garbage truck begins its route in the base point, collects the load in subsequent collection points, then drives the wastes to the disposal site (landfill or sorting plant and returns to the another visited collection points. The filled garbage truck each time goes to the disposal site. It returns to the base after driving wastes from all collection points. Optimization model is based on genetic algorithm where individual is the whole garbage collection plan. Permutation is proposed as the code of the individual.

  13. Agricultural Returns to Labor and the Origins of Work Ethics

    OpenAIRE

    Fouka, Vasiliki; Schlaepfer, Alain

    2017-01-01

    We examine the historical determinants of differences in preferences for work across societies today. Our hypothesis is that a society’s work ethic depends on the role that labor has played in it historically, as an input in agricultural production: societies that have for centuries depended on the cultivation of crops with high returns to labor effort will work longer hours and develop a preference for working hard. We formalize this prediction in the context of a model of endogenous prefere...

  14. Rail Vehicle Vibrations Control Using Parameters Adaptive PID Controller

    Directory of Open Access Journals (Sweden)

    Muzaffer Metin

    2014-01-01

    Full Text Available In this study, vertical rail vehicle vibrations are controlled by the use of conventional PID and parameters which are adaptive to PID controllers. A parameters adaptive PID controller is designed to improve the passenger comfort by intuitional usage of this method that renews the parameters online and sensitively under variable track inputs. Sinusoidal vertical rail misalignment and measured real rail irregularity are considered as two different disruptive effects of the system. Active vibration control is applied to the system through the secondary suspension. The active suspension application of rail vehicle is examined by using 5-DOF quarter-rail vehicle model by using Manchester benchmark dynamic parameters. The new parameters of adaptive controller are optimized by means of genetic algorithm toolbox of MATLAB. Simulations are performed at maximum urban transportation speed (90 km/h of the rail vehicle with ±5% load changes of rail vehicle body to test the robustness of controllers. As a result, superior performance of parameters of adaptive controller is determined in time and frequency domain.

  15. Nonlinear analysis of vehicle control actuations based on controlled invariant sets

    Directory of Open Access Journals (Sweden)

    Németh Balázs

    2016-03-01

    Full Text Available In the paper, an analysis method is applied to the lateral stabilization problem of vehicle systems. The aim is to find the largest state-space region in which the lateral stability of the vehicle can be guaranteed by the peak-bounded control input. In the analysis, the nonlinear polynomial sum-of-squares programming method is applied. A practical computation technique is developed to calculate the maximum controlled invariant set of the system. The method calculates the maximum controlled invariant sets of the steering and braking control systems at various velocities and road conditions. Illustration examples show that, depending on the environments, different vehicle dynamic regions can be reached and stabilized by these controllers. The results can be applied to the theoretical basis of their interventions into the vehicle control system.

  16. Spatiotemporal Local-Remote Senor Fusion (ST-LRSF) for Cooperative Vehicle Positioning.

    Science.gov (United States)

    Jeong, Han-You; Nguyen, Hoa-Hung; Bhawiyuga, Adhitya

    2018-04-04

    Vehicle positioning plays an important role in the design of protocols, algorithms, and applications in the intelligent transport systems. In this paper, we present a new framework of spatiotemporal local-remote sensor fusion (ST-LRSF) that cooperatively improves the accuracy of absolute vehicle positioning based on two state estimates of a vehicle in the vicinity: a local sensing estimate, measured by the on-board exteroceptive sensors, and a remote sensing estimate, received from neighbor vehicles via vehicle-to-everything communications. Given both estimates of vehicle state, the ST-LRSF scheme identifies the set of vehicles in the vicinity, determines the reference vehicle state, proposes a spatiotemporal dissimilarity metric between two reference vehicle states, and presents a greedy algorithm to compute a minimal weighted matching (MWM) between them. Given the outcome of MWM, the theoretical position uncertainty of the proposed refinement algorithm is proven to be inversely proportional to the square root of matching size. To further reduce the positioning uncertainty, we also develop an extended Kalman filter model with the refined position of ST-LRSF as one of the measurement inputs. The numerical results demonstrate that the proposed ST-LRSF framework can achieve high positioning accuracy for many different scenarios of cooperative vehicle positioning.

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

    Science.gov (United States)

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

    2016-02-01

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

  18. Knowledge-based fault diagnosis system for refuse collection vehicle

    International Nuclear Information System (INIS)

    Tan, CheeFai; Juffrizal, K.; Khalil, S. N.; Nidzamuddin, M. Y.

    2015-01-01

    The refuse collection vehicle is manufactured by local vehicle body manufacturer. Currently; the company supplied six model of the waste compactor truck to the local authority as well as waste management company. The company is facing difficulty to acquire the knowledge from the expert when the expert is absence. To solve the problem, the knowledge from the expert can be stored in the expert system. The expert system is able to provide necessary support to the company when the expert is not available. The implementation of the process and tool is able to be standardize and more accurate. The knowledge that input to the expert system is based on design guidelines and experience from the expert. This project highlighted another application on knowledge-based system (KBS) approached in trouble shooting of the refuse collection vehicle production process. The main aim of the research is to develop a novel expert fault diagnosis system framework for the refuse collection vehicle

  19. Knowledge-based fault diagnosis system for refuse collection vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Tan, CheeFai; Juffrizal, K.; Khalil, S. N.; Nidzamuddin, M. Y. [Centre of Advanced Research on Energy, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, Durian Tunggal, Melaka (Malaysia)

    2015-05-15

    The refuse collection vehicle is manufactured by local vehicle body manufacturer. Currently; the company supplied six model of the waste compactor truck to the local authority as well as waste management company. The company is facing difficulty to acquire the knowledge from the expert when the expert is absence. To solve the problem, the knowledge from the expert can be stored in the expert system. The expert system is able to provide necessary support to the company when the expert is not available. The implementation of the process and tool is able to be standardize and more accurate. The knowledge that input to the expert system is based on design guidelines and experience from the expert. This project highlighted another application on knowledge-based system (KBS) approached in trouble shooting of the refuse collection vehicle production process. The main aim of the research is to develop a novel expert fault diagnosis system framework for the refuse collection vehicle.

  20. Improving the Lane Reference Detection for Autonomous Road Vehicle Control

    Directory of Open Access Journals (Sweden)

    Felipe Jiménez

    2016-01-01

    Full Text Available Autonomous road vehicles are increasingly becoming more important and there are several techniques and sensors that are being applied for vehicle control. This paper presents an alternative system for maintaining the position of autonomous vehicles without adding additional elements to the standard sensor architecture, by using a 3D laser scanner for continuously detecting a reference element in situations in which the GNSS receiver fails or provides accuracy below the required level. Considering that the guidance variables are more accurately estimated when dealing with reference points in front of and behind the vehicle, an algorithm based on vehicle dynamics mathematical model is proposed to extend the detected points in cases where the sensor is placed at the front of the vehicle. The algorithm has been tested when driving along a lane delimited by New Jersey barriers at both sides and the results show a correct behaviour. The system is capable of estimating the reference element behind the vehicle with sufficient accuracy when the laser scanner is placed at the front of it, so the robustness of the control input variables (lateral and angular errors estimation is improved making it unnecessary to place the sensor on the vehicle roof or to introduce additional sensors.

  1. Estimating Return on Investment in Translational Research: Methods and Protocols

    Science.gov (United States)

    Trochim, William; Dilts, David M.; Kirk, Rosalind

    2014-01-01

    Assessing the value of clinical and translational research funding on accelerating the translation of scientific knowledge is a fundamental issue faced by the National Institutes of Health and its Clinical and Translational Awards (CTSA). To address this issue, the authors propose a model for measuring the return on investment (ROI) of one key CTSA program, the clinical research unit (CRU). By estimating the economic and social inputs and outputs of this program, this model produces multiple levels of ROI: investigator, program and institutional estimates. A methodology, or evaluation protocol, is proposed to assess the value of this CTSA function, with specific objectives, methods, descriptions of the data to be collected, and how data are to be filtered, analyzed, and evaluated. This paper provides an approach CTSAs could use to assess the economic and social returns on NIH and institutional investments in these critical activities. PMID:23925706

  2. Estimating return on investment in translational research: methods and protocols.

    Science.gov (United States)

    Grazier, Kyle L; Trochim, William M; Dilts, David M; Kirk, Rosalind

    2013-12-01

    Assessing the value of clinical and translational research funding on accelerating the translation of scientific knowledge is a fundamental issue faced by the National Institutes of Health (NIH) and its Clinical and Translational Awards (CTSAs). To address this issue, the authors propose a model for measuring the return on investment (ROI) of one key CTSA program, the clinical research unit (CRU). By estimating the economic and social inputs and outputs of this program, this model produces multiple levels of ROI: investigator, program, and institutional estimates. A methodology, or evaluation protocol, is proposed to assess the value of this CTSA function, with specific objectives, methods, descriptions of the data to be collected, and how data are to be filtered, analyzed, and evaluated. This article provides an approach CTSAs could use to assess the economic and social returns on NIH and institutional investments in these critical activities.

  3. ADOPT: A Historically Validated Light Duty Vehicle Consumer Choice Model

    Energy Technology Data Exchange (ETDEWEB)

    Brooker, A.; Gonder, J.; Lopp, S.; Ward, J.

    2015-05-04

    The Automotive Deployment Option Projection Tool (ADOPT) is a light-duty vehicle consumer choice and stock model supported by the U.S. Department of Energy’s Vehicle Technologies Office. It estimates technology improvement impacts on U.S. light-duty vehicles sales, petroleum use, and greenhouse gas emissions. ADOPT uses techniques from the multinomial logit method and the mixed logit method estimate sales. Specifically, it estimates sales based on the weighted value of key attributes including vehicle price, fuel cost, acceleration, range and usable volume. The average importance of several attributes changes nonlinearly across its range and changes with income. For several attributes, a distribution of importance around the average value is used to represent consumer heterogeneity. The majority of existing vehicle makes, models, and trims are included to fully represent the market. The Corporate Average Fuel Economy regulations are enforced. The sales feed into the ADOPT stock model. It captures key aspects for summing petroleum use and greenhouse gas emissions This includes capturing the change in vehicle miles traveled by vehicle age, the creation of new model options based on the success of existing vehicles, new vehicle option introduction rate limits, and survival rates by vehicle age. ADOPT has been extensively validated with historical sales data. It matches in key dimensions including sales by fuel economy, acceleration, price, vehicle size class, and powertrain across multiple years. A graphical user interface provides easy and efficient use. It manages the inputs, simulation, and results.

  4. Enhanced Regenerative Braking Strategies for Electric Vehicles: Dynamic Performance and Potential Analysis

    OpenAIRE

    Boyi Xiao; Huazhong Lu; Hailin Wang; Jiageng Ruan; Nong Zhang

    2017-01-01

    A regenerative braking system and hydraulic braking system are used in conjunction in the majority of electric vehicles worldwide. We propose a new regenerative braking distribution strategy that is based on multi-input fuzzy control logic while considering the influences of the battery’s state of charge, the brake strength and the motor speed. To verify the braking performance and recovery economy, this strategy was applied to a battery electric vehicle model and compared with two other impr...

  5. On Optimizing Steering Performance of Multi-axle Vehicle Based on Driving Force Control

    Directory of Open Access Journals (Sweden)

    Wu Zhicheng

    2017-01-01

    Full Text Available The steering performance of multi-axle vehicle with independent driving system is affected by the distribution of the wheel driving force. A nonlinear vehicle dynamics model including magic formula tire model for describing 11 DoF four-axle vehicle with dual-front-axle-steering (DFAS system was presented. The influence of different driving force distribution scheme on the steering performance of the vehicle was analyzed. A control strategy for improving the steady response and transient response of the vehicle steering is proposed. The results show: For the steady response, setting different drive force for internal and external wheels according to the actual steering characteristics of the vehicle can effectively improve its steering characteristics; For the transient response, adopting the zero sideslip angle control strategy and using the PID control algorithm to control the driving force of the outside wheel of tear-two-axle, under angle step input, the vehicle sideslip angle can quickly stabilize to 0 and yaw rate also significantly decreases.

  6. Modular Electric Vehicle Program (MEVP). Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    The Modular Electric Vehicle Program (MEVP) was an EV propulsion system development program in which the technical effort was contracted by DOE to Ford Motor Company. The General Electric Company was a major subcontractor to Ford for the development of the electric subsystem. Sundstrand Power Systems was also a subcontractor to Ford, providing a modified gas turbine engine APU for emissions and performance testing as well as a preliminary design and producibility study for a Gas Turbine-APU for potential use in hybrid/electric vehicles. The four-year research and development effort was cost-shared between Ford, General Electric, Sundstrand Power Systems and DOE. The contract was awarded in response to Ford`s unsolicited proposal. The program objective was to bring electric vehicle propulsion system technology closer to commercialization by developing subsystem components which can be produced from a common design and accommodate a wide range of vehicles; i.e., modularize the components. This concept would enable industry to introduce electric vehicles into the marketplace sooner than would be accomplished via traditional designs in that the economies of mass production could be realized across a spectrum of product offerings. This would eliminate the need to dedicate the design and capital investment to a limited volume product offering which would increase consumer cost and/or lengthen the time required to realize a return on the investment.

  7. Computing return times or return periods with rare event algorithms

    Science.gov (United States)

    Lestang, Thibault; Ragone, Francesco; Bréhier, Charles-Edouard; Herbert, Corentin; Bouchet, Freddy

    2018-04-01

    The average time between two occurrences of the same event, referred to as its return time (or return period), is a useful statistical concept for practical applications. For instance insurances or public agencies may be interested by the return time of a 10 m flood of the Seine river in Paris. However, due to their scarcity, reliably estimating return times for rare events is very difficult using either observational data or direct numerical simulations. For rare events, an estimator for return times can be built from the extrema of the observable on trajectory blocks. Here, we show that this estimator can be improved to remain accurate for return times of the order of the block size. More importantly, we show that this approach can be generalised to estimate return times from numerical algorithms specifically designed to sample rare events. So far those algorithms often compute probabilities, rather than return times. The approach we propose provides a computationally extremely efficient way to estimate numerically the return times of rare events for a dynamical system, gaining several orders of magnitude of computational costs. We illustrate the method on two kinds of observables, instantaneous and time-averaged, using two different rare event algorithms, for a simple stochastic process, the Ornstein–Uhlenbeck process. As an example of realistic applications to complex systems, we finally discuss extreme values of the drag on an object in a turbulent flow.

  8. GNSS-based Road Charging Systems - Assessment of Vehicle Location Determination

    DEFF Research Database (Denmark)

    Zabic, Martina

    the collected data from the experiment, in its original for, as it would be used as input for the automated charge calculation process in a road charging system. Furthermore, new methodologies are developed for assessing the performance of the vehicle location determination function in terms of data reliability...

  9. Augmenting camera images for operators of Unmanned Aerial Vehicles

    NARCIS (Netherlands)

    Veltman, J.A.; Oving, A.B.

    2003-01-01

    The manual control of the camera of an unmanned aerial vehicle (UAV) can be difficult due to several factors such as 1) time delays between steering input and changes of the monitor content, 2) low update rates of the camera images and 3) lack of situation awareness due to the remote position of the

  10. The energy efficiency of oil sands extraction: Energy return ratios from 1970 to 2010

    International Nuclear Information System (INIS)

    Brandt, Adam R.; Englander, Jacob; Bharadwaj, Sharad

    2013-01-01

    It has been argued that the oil sands industry is not energy efficient: comparatively large energy inputs are required per unit of energy output from oil sands operations. Unfortunately, quantitative work to date in this area has suffered from poor data availability and uncertain methods. We apply a new methodology and new dataset to compute ERRs (energy return ratios) for the oil sands industry. We collected monthly oil sands energy consumption and output data from 1970 to 2010. Current oil sands operations have mine mouth NERs (net energy returns) of about 6 GJ output per GJ of energy consumed and point of use energy returns of about 3 GJ/GJ. Long-term trends show oil sands operations becoming significantly more efficient: point of use NER increased from about 1 GJ/GJ in 1970 to 3 GJ/GJ in 2010. These energy returns are lower than those observed in historical conventional oil operations, but low energy returns are not likely to hinder development of oil sands operations due to the large resource in place and the ability for largely self-fueled pathways to return significant amounts of energy to society for every unit of external energy supplied. - Highlights: • Oil sands operations have become significantly more energy efficient over the history of the industry. • Oil sands production is largely fueled with energy from the bitumen resource itself, making external energy returns high. • Oil sands production is still significantly less efficient than conventional oil production

  11. FLIS Procedures Manual. Document Identifier Code Input/Output Formats (Fixed Length). Volume 8.

    Science.gov (United States)

    1997-04-01

    DATA ELE- MENTS. SEGMENT R MAY BE REPEATED A MAXIMUM OF THREE (3) TIMES IN ORDER TO ACQUIRE THE REQUIRED MIX OF SEGMENTS OR INDIVIDUAL DATA ELEMENTS TO...preceding record. Marketing input DICs. QI Next DRN of appropriate segment will be QF The assigned NSN or PSCN being can- reflected in accordance with Table...Classified KFC Notification of Possible Duplicate (Sub- KRP Characteristics Data mitter) Follow-Up Interrogation LFU Notification of Return, SSR Transaction

  12. Fire Detection Tradeoffs as a Function of Vehicle Parameters

    Science.gov (United States)

    Urban, David L.; Dietrich, Daniel L.; Brooker, John E.; Meyer, Marit E.; Ruff, Gary A.

    2016-01-01

    Fire survivability depends on the detection of and response to a fire before it has produced an unacceptable environment in the vehicle. This detection time is the result of interplay between the fire burning and growth rates; the vehicle size; the detection system design; the transport time to the detector (controlled by the level of mixing in the vehicle); and the rate at which the life support system filters the atmosphere, potentially removing the detected species or particles. Given the large differences in critical vehicle parameters (volume, mixing rate and filtration rate) the detection approach that works for a large vehicle (e.g. the ISS) may not be the best choice for a smaller crew capsule. This paper examines the impact of vehicle size and environmental control and life support system parameters on the detectability of fires in comparison to the hazard they present. A lumped element model was developed that considers smoke, heat, and toxic product release rates in comparison to mixing and filtration rates in the vehicle. Recent work has quantified the production rate of smoke and several hazardous species from overheated spacecraft polymers. These results are used as the input data set in the lumped element model in combination with the transport behavior of major toxic products released by overheating spacecraft materials to evaluate the necessary alarm thresholds to enable appropriate response to the fire hazard.

  13. An efficiency improved single-phase PFC converter for electric vehicle charger applications

    DEFF Research Database (Denmark)

    Zhu, Dexuan; Tang, Yi; Jin, Chi

    2013-01-01

    This paper presents an efficiency improved single-phase power factor correction (PFC) converter with its target application to plug-in hybrid electric vehicle (PHEV) charging systems. The proposed PFC converter features sinusoidal input current, three-level output characteristic, and wide range...

  14. OSIRIS-REx: Sample Return from Asteroid (101955) Bennu

    Science.gov (United States)

    Lauretta, D. S.; Balram-Knutson, S. S.; Beshore, E.; Boynton, W. V.; Drouet d'Aubigny, C.; DellaGiustina, D. N.; Enos, H. L.; Golish, D. R.; Hergenrother, C. W.; Howell, E. S.; Bennett, C. A.; Morton, E. T.; Nolan, M. C.; Rizk, B.; Roper, H. L.; Bartels, A. E.; Bos, B. J.; Dworkin, J. P.; Highsmith, D. E.; Lorenz, D. A.; Lim, L. F.; Mink, R.; Moreau, M. C.; Nuth, J. A.; Reuter, D. C.; Simon, A. A.; Bierhaus, E. B.; Bryan, B. H.; Ballouz, R.; Barnouin, O. S.; Binzel, R. P.; Bottke, W. F.; Hamilton, V. E.; Walsh, K. J.; Chesley, S. R.; Christensen, P. R.; Clark, B. E.; Connolly, H. C.; Crombie, M. K.; Daly, M. G.; Emery, J. P.; McCoy, T. J.; McMahon, J. W.; Scheeres, D. J.; Messenger, S.; Nakamura-Messenger, K.; Righter, K.; Sandford, S. A.

    2017-10-01

    In May of 2011, NASA selected the Origins, Spectral Interpretation, Resource Identification, and Security- Regolith Explorer (OSIRIS-REx) asteroid sample return mission as the third mission in the New Frontiers program. The other two New Frontiers missions are New Horizons, which explored Pluto during a flyby in July 2015 and is on its way for a flyby of Kuiper Belt object 2014 MU69 on January 1, 2019, and Juno, an orbiting mission that is studying the origin, evolution, and internal structure of Jupiter. The spacecraft departed for near-Earth asteroid (101955) Bennu aboard an United Launch Alliance Atlas V 411 evolved expendable launch vehicle at 7:05 p.m. EDT on September 8, 2016, on a seven-year journey to return samples from Bennu. The spacecraft is on an outbound-cruise trajectory that will result in a rendezvous with Bennu in November 2018. The science instruments on the spacecraft will survey Bennu to measure its physical, geological, and chemical properties, and the team will use these data to select a site on the surface to collect at least 60 g of asteroid regolith. The team will also analyze the remote-sensing data to perform a detailed study of the sample site for context, assess Bennu's resource potential, refine estimates of its impact probability with Earth, and provide ground-truth data for the extensive astronomical data set collected on this asteroid. The spacecraft will leave Bennu in 2021 and return the sample to the Utah Test and Training Range (UTTR) on September 24, 2023.

  15. Influences of braking system faults on the vehicle dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Straky, H.; Kochem, M.; Schmitt, J.; Hild, R.; Isermann, R. [Technische Univ., Darmstadt (Germany). Inst. of Automatic Control

    2001-07-01

    From a safety point of view the braking system is, besides the driver, one of the key subsystems in a car. The driver, as an adaptive control system, might not notice small faults in the hydraulic part of the braking system and sooner or later critical braking situations, e.g. due to a brake-circuit failure, may occur. Most of the drivers are not capable to deal with such critical situations. Therefore this paper investigates the influence of faults in the braking system on the dynamic vehicle behavior and the steering inputs of the driver to keep the vehicle on the desired course. (orig.)

  16. A Column Generation for the Heterogeneous Fixed Fleet Open Vehicle Routing Problem

    Directory of Open Access Journals (Sweden)

    Majid Yousefikhoshbakht

    2017-07-01

    Full Text Available This paper addressed the heterogeneous fixed fleet open vehicle routing problem (HFFOVRP, in which the vehicles are not required to return to the depot after completing a service. In this new problem, the demands of customers are fulfilled by a heterogeneous fixed fleet of vehicles having various capacities, fixed costs and variable costs. This problem is an important variant of the open vehicle routing problem (OVRP and can cover more practical situations in transportation and logistics. Since this problem belongs to NP-hard Problems, An approach based on column generation (CG is applied to solve the HFFOVRP. A tight integer programming model is presented and the linear programming relaxation of which is solved by the CG technique. Since there have been no existing benchmarks, this study generated 19 test problems and the results of the proposed CG algorithm is compared to the results of exact algorithm. Computational experience confirms that the proposed algorithm can provide better solutions within a comparatively shorter period of time.

  17. Autonomous Planning and Replanning for Mine-Sweeping Unmanned Underwater Vehicles

    Science.gov (United States)

    Gaines, Daniel M.

    2010-01-01

    This software generates high-quality plans for carrying out mine-sweeping activities under resource constraints. The autonomous planning and replanning system for unmanned underwater vehicles (UUVs) takes as input a set of prioritized mine-sweep regions, and a specification of available UUV resources including available battery energy, data storage, and time available for accomplishing the mission. Mine-sweep areas vary in location, size of area to be swept, and importance of the region. The planner also works with a model of the UUV, as well as a model of the power consumption of the vehicle when idle and when moving.

  18. Parallel autonomy in automated vehicles : Safe motion generation with minimal intervention

    NARCIS (Netherlands)

    Schwarting, Wilko; Alonso Mora, J.; Pauli, Liam; Karaman, Sertac; Rus, Daniela; Chen, I-Ming; Nakamura, Yoshihiko

    2017-01-01

    Current state-of-the-art vehicle safety systems, such as assistive braking or automatic lane following, are still only able to help in relatively simple driving situations. We introduce a Parallel Autonomy shared-control framework that produces safe trajectories based on human inputs even in much

  19. Metaheuristics for the dynamic stochastic dial-a-ride problem with expected return transports.

    Science.gov (United States)

    Schilde, M; Doerner, K F; Hartl, R F

    2011-12-01

    The problem of transporting patients or elderly people has been widely studied in literature and is usually modeled as a dial-a-ride problem (DARP). In this paper we analyze the corresponding problem arising in the daily operation of the Austrian Red Cross. This nongovernmental organization is the largest organization performing patient transportation in Austria. The aim is to design vehicle routes to serve partially dynamic transportation requests using a fixed vehicle fleet. Each request requires transportation from a patient's home location to a hospital (outbound request) or back home from the hospital (inbound request). Some of these requests are known in advance. Some requests are dynamic in the sense that they appear during the day without any prior information. Finally, some inbound requests are stochastic. More precisely, with a certain probability each outbound request causes a corresponding inbound request on the same day. Some stochastic information about these return transports is available from historical data. The purpose of this study is to investigate, whether using this information in designing the routes has a significant positive effect on the solution quality. The problem is modeled as a dynamic stochastic dial-a-ride problem with expected return transports. We propose four different modifications of metaheuristic solution approaches for this problem. In detail, we test dynamic versions of variable neighborhood search (VNS) and stochastic VNS (S-VNS) as well as modified versions of the multiple plan approach (MPA) and the multiple scenario approach (MSA). Tests are performed using 12 sets of test instances based on a real road network. Various demand scenarios are generated based on the available real data. Results show that using the stochastic information on return transports leads to average improvements of around 15%. Moreover, improvements of up to 41% can be achieved for some test instances.

  20. A Model of Active Roll Vehicle Suspension

    Directory of Open Access Journals (Sweden)

    I. Čech

    2010-01-01

    Full Text Available This paper describes active suspension with active roll for four-wheel vehicle (bus by means of an in-series pump actuator with doubled hydropneumatic springs. It also gives full control law with no sky-craping. Lateral stiffness and solid axle geometry in the mechanical model are not neglected. Responses to lateral input as well as responses to statistical unevennesses show considerable improvement of passengers comfort and safety when cornering.

  1. 26 CFR 301.6103(h)(2)-1 - Disclosure of returns and return information (including taxpayer return information) to and by...

    Science.gov (United States)

    2010-04-01

    ... administration. 301.6103(h)(2)-1 Section 301.6103(h)(2)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... Returns Returns and Records § 301.6103(h)(2)-1 Disclosure of returns and return information (including..., shall, to the extent provided by section 6103(h)(2) (A), (B), and (C) and subject to the requirements of...

  2. Performansi Algoritma CODEQ dalam Penyelesaian Vehicle Routing Problem

    Directory of Open Access Journals (Sweden)

    Annisa Kesy Garside

    2014-01-01

    Full Text Available Genetic Algorithm, Tabu Search, Simulated Annealing, and Ant Colony Optimization showed a good performance in solving vehicle routing problem. However, the generated solution of those algorithms was changeable regarding on the input parameter of each algorithm. CODEQ is a new, parameter free meta-heuristic algorithm that had been successfully used to solve constrained optimization problems, integer programming, and feed-forward neural network. The purpose of this research are improving CODEQ algorithm to solve vehicle routing problem and testing the performance of the improved algorithm. CODEQ algorithm is started with population initiation as initial solution, generated of mutant vector for each parent in every iteration, replacement of parent by mutant when fitness function value of mutant is better than parent’s, generated of new vector for each iteration based on opposition value or chaos principle, replacement of worst solution by new vector when fitness function value of new vector is better, iteration ceasing when stooping criterion is achieved, and sub-tour determination based on vehicle capacity constraint. The result showed that the average deviation of the best-known and the best-test value is 6.35%. Therefore, CODEQ algorithm is good in solving vehicle routing problem.

  3. Pitch Channel Control of a REMUS AUV with Input Saturation and Coupling Disturbances

    Directory of Open Access Journals (Sweden)

    Nailong Wu

    2018-02-01

    Full Text Available The motion of an underwater vehicle is prone to be affected by time-varying model parameters and the actuator limitation in control practice. Adaptive control is an effective method to deal with the general system dynamic uncertainties and disturbances. However, the effect of disturbances control on transient dynamics is not prominent. In this paper, we redesign the L 1 adaptive control architecture (L1AC with anti-windup (AW compensator to guarantee robust and fast adaption of the underwater vehicle with input saturation and coupling disturbances. To reduce the fluctuation of vehicle states, the Riccati-based AW compensator is utilized to compensate the output signal from L1AC controller via taking proper modification. The proposed method is applied to the pitch channel of REMUS vehicle’s six Degrees Of Freedom (DOF model with strong nonlinearities and compared with L1AC baseline controller. Simulations show the effectiveness of the proposed control strategy compared to the original L1AC. Besides, the fluctuation in roll channel coupled with pitch channel is suppressed according to the performances of control tests.

  4. A Hybrid Genetic-Simulated Annealing Algorithm for the Location-Inventory-Routing Problem Considering Returns under E-Supply Chain Environment

    Science.gov (United States)

    Guo, Hao; Fu, Jing

    2013-01-01

    Facility location, inventory control, and vehicle routes scheduling are critical and highly related problems in the design of logistics system for e-business. Meanwhile, the return ratio in Internet sales was significantly higher than in the traditional business. Many of returned merchandise have no quality defects, which can reenter sales channels just after a simple repackaging process. Focusing on the existing problem in e-commerce logistics system, we formulate a location-inventory-routing problem model with no quality defects returns. To solve this NP-hard problem, an effective hybrid genetic simulated annealing algorithm (HGSAA) is proposed. Results of numerical examples show that HGSAA outperforms GA on computing time, optimal solution, and computing stability. The proposed model is very useful to help managers make the right decisions under e-supply chain environment. PMID:24489489

  5. A hybrid genetic-simulated annealing algorithm for the location-inventory-routing problem considering returns under e-supply chain environment.

    Science.gov (United States)

    Li, Yanhui; Guo, Hao; Wang, Lin; Fu, Jing

    2013-01-01

    Facility location, inventory control, and vehicle routes scheduling are critical and highly related problems in the design of logistics system for e-business. Meanwhile, the return ratio in Internet sales was significantly higher than in the traditional business. Many of returned merchandise have no quality defects, which can reenter sales channels just after a simple repackaging process. Focusing on the existing problem in e-commerce logistics system, we formulate a location-inventory-routing problem model with no quality defects returns. To solve this NP-hard problem, an effective hybrid genetic simulated annealing algorithm (HGSAA) is proposed. Results of numerical examples show that HGSAA outperforms GA on computing time, optimal solution, and computing stability. The proposed model is very useful to help managers make the right decisions under e-supply chain environment.

  6. A Hybrid Genetic-Simulated Annealing Algorithm for the Location-Inventory-Routing Problem Considering Returns under E-Supply Chain Environment

    Directory of Open Access Journals (Sweden)

    Yanhui Li

    2013-01-01

    Full Text Available Facility location, inventory control, and vehicle routes scheduling are critical and highly related problems in the design of logistics system for e-business. Meanwhile, the return ratio in Internet sales was significantly higher than in the traditional business. Many of returned merchandise have no quality defects, which can reenter sales channels just after a simple repackaging process. Focusing on the existing problem in e-commerce logistics system, we formulate a location-inventory-routing problem model with no quality defects returns. To solve this NP-hard problem, an effective hybrid genetic simulated annealing algorithm (HGSAA is proposed. Results of numerical examples show that HGSAA outperforms GA on computing time, optimal solution, and computing stability. The proposed model is very useful to help managers make the right decisions under e-supply chain environment.

  7. Potential use of battery packs from NCAP tested vehicles.

    Energy Technology Data Exchange (ETDEWEB)

    Lamb, Joshua; Orendorff, Christopher J.

    2013-10-01

    Several large electric vehicle batteries available to the National Highway Traffic Safety Administration are candidates for use in future safety testing programs. The batteries, from vehicles subjected to NCAP crashworthiness testing, are considered potentially damaged due to the nature of testing their associated vehicles have been subjected to. Criteria for safe shipping to Sandia is discussed, as well as condition the batteries must be in to perform testing work. Also discussed are potential tests that could be performed under a variety of conditions. The ultimate value of potential testing performed on these cells will rest on the level of access available to the battery pack, i.e. external access only, access to the on board monitoring system/CAN port or internal electrical access to the battery. Greater access to the battery than external visual and temperature monitoring would likely require input from the battery manufacturer.

  8. Nearest greedy for solving the waste collection vehicle routing problem: A case study

    Science.gov (United States)

    Mat, Nur Azriati; Benjamin, Aida Mauziah; Abdul-Rahman, Syariza; Wibowo, Antoni

    2017-11-01

    This paper presents a real case study pertaining to an issue related to waste collection in the northern part of Malaysia by using a constructive heuristic algorithm known as the Nearest Greedy (NG) technique. This technique has been widely used to devise initial solutions for issues concerning vehicle routing. Basically, the waste collection cycle involves the following steps: i) each vehicle starts from a depot, ii) visits a number of customers to collect waste, iii) unloads waste at the disposal site, and lastly, iv) returns to the depot. Moreover, the sample data set used in this paper consisted of six areas, where each area involved up to 103 customers. In this paper, the NG technique was employed to construct an initial route for each area. The solution proposed from the technique was compared with the present vehicle routes implemented by a waste collection company within the city. The comparison results portrayed that NG offered better vehicle routes with a 11.07% reduction of the total distance traveled, in comparison to the present vehicle routes.

  9. SIGMA/B, Doses in Space Vehicle for Multiple Trajectories, Various Radiation Source

    International Nuclear Information System (INIS)

    Jordan, T.M.

    2003-01-01

    1 - Description of problem or function: SIGMA/B calculates radiation dose at arbitrary points inside a space vehicle, taking into account vehicle geometry, heterogeneous placement of equipment and stores, vehicle materials, time-weighted astronaut positions and many radiation sources from mission trajectories, e.g. geomagnetically trapped protons and electrons, solar flare particles, galactic cosmic rays and their secondary radiations. The vehicle geometry, equipment and supplies, and man models are described by quadric surfaces. The irradiating flux field may be anisotropic. The code can be used to perform simultaneous dose calculations for multiple vehicle trajectories, each involving several radiation sources. Results are presented either as dose as a function of shield thickness, or the dose received through designated outer sections of the vehicle. 2 - Method of solution: Automatic sectoring of the vehicle is performed by a Simpson's rule integration over angle; the dose is computed by a numerical angular integration of the dose attenuation kernels about the dose points. The kernels are curve-fit functions constructed from input data tables. 3 - Restrictions on the complexity of the problem: The code uses variable dimensioning techniques to store data. The only restriction on problem size is the available core storage

  10. Nonlinear dynamics modeling and simulation of two-wheeled self-balancing vehicle

    Directory of Open Access Journals (Sweden)

    Yunping Liu

    2016-11-01

    Full Text Available Two-wheeled self-balancing vehicle system is a kind of naturally unstable underactuated system with high-rank unstable multivariable strongly coupling complicated dynamic nonlinear property. Nonlinear dynamics modeling and simulation, as a basis of two-wheeled self-balancing vehicle dynamics research, has the guiding effect for system design of the project demonstration and design phase. Dynamics model of the two-wheeled self-balancing vehicle is established by importing a TSi ProPac package to the Mathematica software (version 8.0, which analyzes the stability and calculates the Lyapunov exponents of the system. The relationship between external force and stability of the system is analyzed by the phase trajectory. Proportional–integral–derivative control is added to the system in order to improve the stability of the two-wheeled self-balancing vehicle. From the research, Lyapunov exponent can be used to research the stability of hyperchaos system. The stability of the two-wheeled self-balancing vehicle is better by inputting the proportional–integral–derivative control. The Lyapunov exponent and phase trajectory can help us analyze the stability of a system better and lay the foundation for the analysis and control of the two-wheeled self-balancing vehicle system.

  11. Vehicle Detection for RCTA/ANS (Autonomous Navigation System)

    Science.gov (United States)

    Brennan, Shane; Bajracharya, Max; Matthies, Larry H.; Howard, Andrew B.

    2012-01-01

    Using a stereo camera pair, imagery is acquired and processed through the JPLV stereo processing pipeline. From this stereo data, large 3D blobs are found. These blobs are then described and classified by their shape to determine which are vehicles and which are not. Prior vehicle detection algorithms are either targeted to specific domains, such as following lead cars, or are intensity- based methods that involve learning typical vehicle appearances from a large corpus of training data. In order to detect vehicles, the JPL Vehicle Detection (JVD) algorithm goes through the following steps: 1. Take as input a left disparity image and left rectified image from JPLV stereo. 2. Project the disparity data onto a two-dimensional Cartesian map. 3. Perform some post-processing of the map built in the previous step in order to clean it up. 4. Take the processed map and find peaks. For each peak, grow it out into a map blob. These map blobs represent large, roughly vehicle-sized objects in the scene. 5. Take these map blobs and reject those that do not meet certain criteria. Build descriptors for the ones that remain. Pass these descriptors onto a classifier, which determines if the blob is a vehicle or not. The probability of detection is the probability that if a vehicle is present in the image, is visible, and un-occluded, then it will be detected by the JVD algorithm. In order to estimate this probability, eight sequences were ground-truthed from the RCTA (Robotics Collaborative Technology Alliances) program, totaling over 4,000 frames with 15 unique vehicles. Since these vehicles were observed at varying ranges, one is able to find the probability of detection as a function of range. At the time of this reporting, the JVD algorithm was tuned to perform best at cars seen from the front, rear, or either side, and perform poorly on vehicles seen from oblique angles.

  12. Control techniques for an automated mixed traffic vehicle

    Science.gov (United States)

    Meisenholder, G. W.; Johnston, A. R.

    1977-01-01

    The paper describes an automated mixed traffic vehicle (AMTV), a driverless low-speed tram designed to operate in mixed pedestrian and vehicular traffic. The vehicle is a six-passenger electric tram equipped with sensing and control which permit it to function on existing streets in an automatic mode. The design includes established wire-following techniques for steering and near-IR headway sensors. A 7-mph cruise speed is reduced to 2 mph or a complete stop in response to sensor (or passenger) inputs. The AMTV performance is evaluated by operation on a loop route and by simulation. Some necessary improvements involving sensors, sensor pattern, use of an audible signal, and control lag are discussed. It is suggested that appropriate modifications will eliminate collision incidents.

  13. Analyzing Real-World Light Duty Vehicle Efficiency Benefits

    Energy Technology Data Exchange (ETDEWEB)

    Gonder, Jeffrey; Wood, Eric; Chaney, Larry; Holden, Jacob; Jeffers, Matthew; Wang, Lijuan

    2016-06-08

    Off-cycle technologies represent an important pathway to achieve real-world fuel savings, through which OEMs can potentially receive credit toward CAFE compliance. DOE national labs such as NREL are well positioned to provide objective input on these technologies using large, national data sets in conjunction with OEM- and technology-specific testing. This project demonstrates an approach that combines vehicle testing (dynamometer and on-road) with powertrain modeling and simulation over large, representative datasets to quantify real-world fuel economy. The approach can be applied to specific off-cycle technologies (engine encapsulation, start/stop, connected vehicle, etc.) in A/B comparisons to support calculation of realistic real-world impacts. Future work will focus on testing-based A/B technology comparisons that demonstrate the significance of this approach.

  14. Vision based speed breaker detection for autonomous vehicle

    Science.gov (United States)

    C. S., Arvind; Mishra, Ritesh; Vishal, Kumar; Gundimeda, Venugopal

    2018-04-01

    In this paper, we are presenting a robust and real-time, vision-based approach to detect speed breaker in urban environments for autonomous vehicle. Our method is designed to detect the speed breaker using visual inputs obtained from a camera mounted on top of a vehicle. The method performs inverse perspective mapping to generate top view of the road and segment out region of interest based on difference of Gaussian and median filter images. Furthermore, the algorithm performs RANSAC line fitting to identify the possible speed breaker candidate region. This initial guessed region via RANSAC, is validated using support vector machine. Our algorithm can detect different categories of speed breakers on cement, asphalt and interlock roads at various conditions and have achieved a recall of 0.98.

  15. A path-following driver/vehicle model with optimized lateral dynamic controller

    Directory of Open Access Journals (Sweden)

    Behrooz Mashadi

    Full Text Available Reduction in traffic congestion and overall number of accidents, especially within the last decade, can be attributed to the enormous progress in active safety. Vehicle path following control with the presence of driver commands can be regarded as one of the important issues in vehicle active safety systems development and more realistic explanation of vehicle path tracking problem. In this paper, an integrated driver/DYC control system is presented that regulates the steering angle and yaw moment, considering driver previewed path. Thus, the driver previewed distance, the heading error and the lateral deviation between the vehicle and desired path are used as inputs. Then, the controller determines and applies a corrective steering angle and a direct yaw moment to make the vehicle follow the desired path. A PID controller with optimized gains is used for the control of integrated driver/DYC system. Genetic Algorithm as an intelligent optimization method is utilized to adapt PID controller gains for various working situations. Proposed integrated driver/DYC controller is examined on lane change manuvers andthe sensitivity of the control system is investigated through the changes in the driver model and vehicle parameters. Simulation results show the pronounced effectiveness of the controller in vehicle path following and stability.

  16. Predictable return distributions

    DEFF Research Database (Denmark)

    Pedersen, Thomas Quistgaard

    trace out the entire distribution. A univariate quantile regression model is used to examine stock and bond return distributions individually, while a multivariate model is used to capture their joint distribution. An empirical analysis on US data shows that certain parts of the return distributions......-of-sample analyses show that the relative accuracy of the state variables in predicting future returns varies across the distribution. A portfolio study shows that an investor with power utility can obtain economic gains by applying the empirical return distribution in portfolio decisions instead of imposing...

  17. Analysis of technician-economic viability of vehicles conversion to bio combustible, natural gas -gasoline systems for the Colombian case

    International Nuclear Information System (INIS)

    Agudelo S, John Ramiro; Munoz B, Juan; Trujillo R, Luis

    2000-01-01

    This paper shows from an economical and technical point of view the conversion to bi fuel systems for operation with natural gas. The cost benefits obtained is near 49%. The return internal rate analysis is around 12 months and it is function of distance and vehicles efficiency for carbureted spark ignition engines the loss of power and torque is around 25-30%, which affects vehicle velocity in 15-25%

  18. Impact of reduced mass of light commercial vehicles on fuel consumption, CO2 emissions, air quality, and socio-economic costs.

    Science.gov (United States)

    Cecchel, S; Chindamo, D; Turrini, E; Carnevale, C; Cornacchia, G; Gadola, M; Panvini, A; Volta, M; Ferrario, D; Golimbioschi, R

    2018-02-01

    This study presents a modelling system to evaluate the impact of weight reduction in light commercial vehicles with diesel engines on air quality and greenhouse gas emissions. The PROPS model assesses the emissions of one vehicle in the aforementioned category and its corresponding reduced-weight version. The results serve as an input to the RIAT+ tool, an air quality integrated assessment modelling system. This paper applies the tools in a case study in the Lombardy region (Italy) and discusses the input data pre-processing, the PROPS-RIAT+ modelling system runs, and the results. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Return-to-Work Program for Injured Workers: Factors of Successful Return to Employment.

    Science.gov (United States)

    Awang, Halimah; Shahabudin, Sharifah Muhairah; Mansor, Norma

    2016-11-01

    This study examined the factors of successful return to employment among participants in the return to work program (RTW) following work-related injury. Data were obtained from the Social Security Organization database containing 9850 injured workers who underwent RTW in 2010 to 2013. About 65% had successfully returned to employment. Significant factors of successful return include gender, employer interest, motivation, age, intervention duration, and type of injury. Male and motivated employees were more likely to return to employment compared with female and unmotivated employees, respectively. Participants from interested employers were 23.22 times more likely to return to work than those from uninterested employers, whereas participants whose intervention period exceeded 5 months were 41% less likely to return to work compared with those whose intervention period was within 3 months. Appropriate strategy and enhanced collaboration between the stakeholders would improve the proportion of successful return to employment. © 2016 APJPH.

  20. Analytical Modelling of Wireless Power Transfer (WPT) Systems for Electric Vehicle Application

    Energy Technology Data Exchange (ETDEWEB)

    Chinthavali, Madhu Sudhan [ORNL; Campbell, Steven L [ORNL

    2016-01-01

    This paper presents an analytical model for wireless power transfer system used in electric vehicle application. The equivalent circuit model for each major component of the system is described, including the input voltage source, resonant network, transformer, nonlinear diode rectifier load, etc. Based on the circuit model, the primary side compensation capacitance, equivalent input impedance, active / reactive power are calculated, which provides a guideline for parameter selection. Moreover, the voltage gain curve from dc output to dc input is derived as well. A hardware prototype with series-parallel resonant stage is built to verify the developed model. The experimental results from the hardware are compared with the model predicted results to show the validity of the model.

  1. Intelligent behaviors through vehicle-to-vehicle and vehicle-to-infrastructure communication

    Science.gov (United States)

    Garcia, Richard D.; Sturgeon, Purser; Brown, Mike

    2012-06-01

    The last decade has seen a significant increase in intelligent safety devices on private automobiles. These devices have both increased and augmented the situational awareness of the driver and in some cases provided automated vehicle responses. To date almost all intelligent safety devices have relied on data directly perceived by the vehicle. This constraint has a direct impact on the types of solutions available to the vehicle. In an effort to improve the safety options available to a vehicle, numerous research laboratories and government agencies are investing time and resources into connecting vehicles to each other and to infrastructure-based devices. This work details several efforts in both the commercial vehicle and the private auto industries to increase vehicle safety and driver situational awareness through vehicle-to-vehicle and vehicle-to-infrastructure communication. It will specifically discuss intelligent behaviors being designed to automatically disable non-compliant vehicles, warn tractor trailer vehicles of unsafe lane maneuvers such as lane changes, passing, and merging, and alert drivers to non-line-of-sight emergencies.

  2. Techno-economic and behavioural analysis of battery electric, hydrogen fuel cell and hybrid vehicles in a future sustainable road transport system in the UK

    Energy Technology Data Exchange (ETDEWEB)

    Offer, G.J., E-mail: gregory.offer@imperial.ac.u [Department Earth Science Engineering, Imperial College London, SW7 2AZ London (United Kingdom); Contestabile, M. [Centre for Environmental Policy, Imperial College London, SW7 2AZ (United Kingdom); Howey, D.A. [Department of Electrical and Electronic Engineering, Imperial College London, SW7 2AZ (United Kingdom); Clague, R. [Energy Futures Lab, Imperial College London, SW7 2AZ (United Kingdom); Brandon, N.P. [Department Earth Science Engineering, Imperial College London, SW7 2AZ London (United Kingdom)

    2011-04-15

    This paper conducts a techno-economic study on hydrogen Fuel Cell Electric Vehicles (FCV), Battery Electric Vehicles (BEV) and hydrogen Fuel Cell plug-in Hybrid Electric Vehicles (FCHEV) in the UK using cost predictions for 2030. The study includes an analysis of data on distance currently travelled by private car users daily in the UK. Results show that there may be diminishing economic returns for Plug-in Hybrid Electric Vehicles (PHEV) with battery sizes above 20 kWh, and the optimum size for a PHEV battery is between 5 and 15 kWh. Differences in behaviour as a function of vehicle size are demonstrated, which decreases the percentage of miles that can be economically driven using electricity for a larger vehicle. Decreasing carbon dioxide emissions from electricity generation by 80% favours larger optimum battery sizes as long as carbon is priced, and will reduce emissions considerably. However, the model does not take into account reductions in carbon dioxide emissions from hydrogen generation, assuming hydrogen will still be produced from steam reforming methane in 2030. - Research highlights: {yields} Report diminishing returns for plug-in hybrids with battery sizes above 20 kWh. {yields} The optimum size for a PHEV battery is between 5 and 15 kWh. {yields} Current behaviour decreases percentage electric only miles for larger vehicles. {yields} Low carbon electricity favours larger battery sizes as long as carbon is priced. {yields} Reinforces that the FCHEV is a cheaper option than conventional ICE vehicles in 2030.

  3. Techno-economic and behavioural analysis of battery electric, hydrogen fuel cell and hybrid vehicles in a future sustainable road transport system in the UK

    International Nuclear Information System (INIS)

    Offer, G.J.; Contestabile, M.; Howey, D.A.; Clague, R.; Brandon, N.P.

    2011-01-01

    This paper conducts a techno-economic study on hydrogen Fuel Cell Electric Vehicles (FCV), Battery Electric Vehicles (BEV) and hydrogen Fuel Cell plug-in Hybrid Electric Vehicles (FCHEV) in the UK using cost predictions for 2030. The study includes an analysis of data on distance currently travelled by private car users daily in the UK. Results show that there may be diminishing economic returns for Plug-in Hybrid Electric Vehicles (PHEV) with battery sizes above 20 kWh, and the optimum size for a PHEV battery is between 5 and 15 kWh. Differences in behaviour as a function of vehicle size are demonstrated, which decreases the percentage of miles that can be economically driven using electricity for a larger vehicle. Decreasing carbon dioxide emissions from electricity generation by 80% favours larger optimum battery sizes as long as carbon is priced, and will reduce emissions considerably. However, the model does not take into account reductions in carbon dioxide emissions from hydrogen generation, assuming hydrogen will still be produced from steam reforming methane in 2030. - Research highlights: → Report diminishing returns for plug-in hybrids with battery sizes above 20 kWh. → The optimum size for a PHEV battery is between 5 and 15 kWh. → Current behaviour decreases percentage electric only miles for larger vehicles. → Low carbon electricity favours larger battery sizes as long as carbon is priced. → Reinforces that the FCHEV is a cheaper option than conventional ICE vehicles in 2030.

  4. Vibration study of a vehicle suspension assembly with the finite element method

    Science.gov (United States)

    Cătălin Marinescu, Gabriel; Castravete, Ştefan-Cristian; Dumitru, Nicolae

    2017-10-01

    The main steps of the present work represent a methodology of analysing various vibration effects over suspension mechanical parts of a vehicle. A McPherson type suspension from an existing vehicle was created using CAD software. Using the CAD model as input, a finite element model of the suspension assembly was developed. Abaqus finite element analysis software was used to pre-process, solve, and post-process the results. Geometric nonlinearities are included in the model. Severe sources of nonlinearities such us friction and contact are also included in the model. The McPherson spring is modelled as linear spring. The analysis include several steps: preload, modal analysis, the reduction of the model to 200 generalized coordinates, a deterministic external excitation, a random excitation that comes from different types of roads. The vibration data used as an input for the simulation were previously obtained by experimental means. Mathematical expressions used for the simulation were also presented in the paper.

  5. Vehicle-use intensity in China: Current status and future trend

    International Nuclear Information System (INIS)

    Huo Hong; Zhang Qiang; He Kebin; Yao Zhiliang; Wang, Michael

    2012-01-01

    Vehicle-use intensity (kilometers traveled per vehicle per year or VKT) is important because it directly affects simulation results for vehicle fuel use and emissions, but the poor understanding of VKT in China could significantly affect the accuracy of estimation of total fuel use and CO 2 emissions, and thus impair precise evaluation of the effects of associated energy and environmental policies. As an important component of our work on the Fuel Economy and Environmental Impacts (FEEI) model, we collected VKT survey data in China from available sources and conducted additional surveys during 2004 and 2010, from which we derived VKT values and VKT-age functions by vehicle type for China. We also projected the future VKT for China by examining the relationship of vehicle use to per-capita GDP in 20 other countries worldwide. The purpose of this work is to achieve a better understanding of vehicle-use intensity in China and to generate reliable VKT input (current and future VKT levels) for the FEEI model. The VKT results obtained from this work could also benefit other work in the field associated with vehicle energy use and emissions. - Highlights: ► VKT is key in estimating fuel use and emissions, but its knowledge is poor in China. ► We determined VKT in China from available survey data and the surveys we conducted. ► VKT-age functions by vehicle type were derived from the surveys we conducted. ► Future VKT was projected based on vehicle use to per-capita GDP in 20 countries.

  6. A novel multi-drive electric vehicle system control based on multi-input multi-output PID controller

    Directory of Open Access Journals (Sweden)

    Gasbaoui Brahim

    2012-01-01

    Full Text Available In-wheel-motor drive electric vehicle (EV is an innovative configuration of the modern EV, in which each wheel is driven individually by an electric motor. The classical traction motor control called the Independent Machine Control Structure (IMCS using a PID speed controller presents major inconveniences in modern EV safety, when the proposed control can not ensure stability of the EV with differing road topology and variations of speed. A new approach is proposed for a control of a two-in-wheel-motor drive EV, called the Maximum Control Structure MCS. This is based on a multivariable PID (MIMO-PID strategy, which is employed to estimate the linear speed error of each of the two back driving wheels, when the error of each wheel is taken into account in the other speed control computations. Simulation results show that the new control system presents increased safety for the EVs compared with the IMCS strategy and can maintain the error slip rate within the optimal range, ensuring the stability of the vehicle either in a straight or a curved line.

  7. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Science.gov (United States)

    2010-04-01

    ... the case of a joint return made under section 6013(b), the period of limitations provided in sections... (c)(1) of this section, relating to the application of sections 6501 and 6651 with respect to a joint... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Joint return after filing separate return. 1...

  8. Use of nonlinear asymmetrical shock absorber to improve comfort on passenger vehicles

    Science.gov (United States)

    Silveira, M.; Pontes, B. R.; Balthazar, J. M.

    2014-03-01

    In this study the behaviour of two different types of shock absorbers, symmetrical (linear) and asymmetrical (nonlinear) is compared for use on passenger vehicles. The analyses use different standard road inputs and include variation of the severity parameter, the asymmetry ratio and the velocity of the vehicle. Performance indices and acceleration values are used to assess the efficacy of the asymmetrical systems. The comparisons show that the asymmetrical system, with nonlinear characteristics, tends to have a smoother and more progressive performance, both for vertical and angular movements. The half-car front asymmetrical system was introduced, and the simulation results show that the use of the asymmetrical system only at the front of the vehicle can further diminish the angular oscillations. As lower levels of acceleration are essential for improved ride comfort, the use of asymmetrical systems for vibrations and impact absorption can be a more advantageous choice for passenger vehicles.

  9. Simulation Research on Vehicle Active Suspension Controller Based on G1 Method

    Science.gov (United States)

    Li, Gen; Li, Hang; Zhang, Shuaiyang; Luo, Qiuhui

    2017-09-01

    Based on the order relation analysis method (G1 method), the optimal linear controller of vehicle active suspension is designed. The system of the main and passive suspension of the single wheel vehicle is modeled and the system input signal model is determined. Secondly, the system motion state space equation is established by the kinetic knowledge and the optimal linear controller design is completed with the optimal control theory. The weighting coefficient of the performance index coefficients of the main passive suspension is determined by the relational analysis method. Finally, the model is simulated in Simulink. The simulation results show that: the optimal weight value is determined by using the sequence relation analysis method under the condition of given road conditions, and the vehicle acceleration, suspension stroke and tire motion displacement are optimized to improve the comprehensive performance of the vehicle, and the active control is controlled within the requirements.

  10. Motion coordination for VTOL unmanned aerial vehicles attitude synchronisation and formation control

    CERN Document Server

    Abdessameud, Abdelkader

    2013-01-01

    Motion Coordination for VTOL Unmanned Aerial Vehicles develops new control design techniques for the distributed coordination of a team of autonomous unmanned aerial vehicles. In particular, it provides new control design approaches for the attitude synchronization of a formation of rigid body systems. In addition, by integrating new control design techniques with some concepts from nonlinear control theory and multi-agent systems, it presents  a new theoretical framework for the formation control of a class of under-actuated aerial vehicles capable of vertical take-off and landing. Several practical problems related to the systems’ inputs, states measurements, and  restrictions on the interconnection  topology  between the aerial vehicles in the team  are addressed. Worked examples with sufficient details and simulation results are provided to illustrate the applicability and effectiveness of the theoretical results discussed in the book. The material presented is primarily intended for researchers an...

  11. Launch vehicle selection model

    Science.gov (United States)

    Montoya, Alex J.

    1990-01-01

    Over the next 50 years, humans will be heading for the Moon and Mars to build scientific bases to gain further knowledge about the universe and to develop rewarding space activities. These large scale projects will last many years and will require large amounts of mass to be delivered to Low Earth Orbit (LEO). It will take a great deal of planning to complete these missions in an efficient manner. The planning of a future Heavy Lift Launch Vehicle (HLLV) will significantly impact the overall multi-year launching cost for the vehicle fleet depending upon when the HLLV will be ready for use. It is desirable to develop a model in which many trade studies can be performed. In one sample multi-year space program analysis, the total launch vehicle cost of implementing the program reduced from 50 percent to 25 percent. This indicates how critical it is to reduce space logistics costs. A linear programming model has been developed to answer such questions. The model is now in its second phase of development, and this paper will address the capabilities of the model and its intended uses. The main emphasis over the past year was to make the model user friendly and to incorporate additional realistic constraints that are difficult to represent mathematically. We have developed a methodology in which the user has to be knowledgeable about the mission model and the requirements of the payloads. We have found a representation that will cut down the solution space of the problem by inserting some preliminary tests to eliminate some infeasible vehicle solutions. The paper will address the handling of these additional constraints and the methodology for incorporating new costing information utilizing learning curve theory. The paper will review several test cases that will explore the preferred vehicle characteristics and the preferred period of construction, i.e., within the next decade, or in the first decade of the next century. Finally, the paper will explore the interaction

  12. Optimal scheduling for vehicle-to-grid operation with stochastic connection of plug-in electric vehicles to smart grid

    International Nuclear Information System (INIS)

    Jian, Linni; Zheng, Yanchong; Xiao, Xinping; Chan, C.C.

    2015-01-01

    Highlights: • A novel event-triggered scheduling scheme for vehicle-to-grid (V2G) operation is proposed. • New scheme can handle the uncertainty arising from stochastic connection of electric vehicles. • New scheme aims at minimizing the overall load variance of power grid by V2G operation. • Method to evaluate the performance of proposed scheme is elaborated and demonstrated. - Abstract: Vehicle-to-grid (V2G) operation of plug-in electric vehicles (PEVs) is attracting increasing attention since it can assist to improve the efficiency and reliability of power grid, as well as reduce the operating cost and greenhouse gas emission of electric vehicles. Within the scheme of V2G operation, PEVs are expected to serve as a novel distributed energy storage system (ESS) to help achieve the balance between supply and demand of power grid. One of the key difficulties concerning its practical implementation lies in that the availability of PEVs as ESS for grid remains highly uncertain due to their mobility as transportation tools. To address this issue, a novel event-triggered scheduling scheme for V2G operation based on the scenario of stochastic PEV connection to smart grid is proposed in this paper. Firstly, the mathematical model is formulated. Secondly, the preparation of input data for systematic evaluation is introduced and the case study is conducted. Finally, statistic analysis results demonstrate that our proposed V2G scheduling scheme can dramatically smooth out the fluctuation in power load profiles

  13. Vision-GPS Fusion for Guidance of an Autonomous Vehicle in Row Crops

    DEFF Research Database (Denmark)

    Bak, Thomas

    2001-01-01

    This paper presents a real-time localization system for an autonomous vehicle passing through 0.25 m wide crop rows at 6 km/h. Localization is achieved by fusion of mea-surements from a row guidance sensor and a GPS receiver. Conventional agricultural practice applies inputs such as herbicide...

  14. Importance Of Quality Control in Reducing System Risk, a Lesson Learned From The Shuttle and a Recommendation for Future Launch Vehicles

    Science.gov (United States)

    Safie, Fayssal M.; Messer, Bradley P.

    2006-01-01

    This paper presents lessons learned from the Space Shuttle return to flight experience and the importance of these lessons learned in the development of new the NASA Crew Launch Vehicle (CLV). Specifically, the paper discusses the relationship between process control and system risk, and the importance of process control in improving space vehicle flight safety. It uses the External Tank (ET) Thermal Protection System (TPS) experience and lessons learned from the redesign and process enhancement activities performed in preparation for Return to Flight after the Columbia accident. The paper also, discusses in some details, the Probabilistic engineering physics based risk assessment performed by the Shuttle program to evaluate the impact of TPS failure on system risk and the application of the methodology to the CLV.

  15. The Risk Return Relationship: Evidence from Index Return and Realised Variance Series

    OpenAIRE

    Minxian Yang

    2014-01-01

    The risk return relationship is analysed in bivariate models for return and realised variance(RV) series. Based on daily time series from 21 international market indices for more than 13 years (January 2000 to February 2013), the empirical findings support the arguments of risk return tradeoff, volatility feedback and statistical balance. It is reasoned that the empirical risk return relationship is primarily shaped by two important data features: the negative contemporaneous correlation betw...

  16. [Real world instantaneous emission simulation for light-duty diesel vehicle].

    Science.gov (United States)

    Huang, Cheng; Chen, Chang-Hong; Dai, Pu; Li, Li; Huang, Hai-Ying; Cheng, Zhen; Jia, Ji-Hong

    2008-10-01

    Core architecture and input parameters of CMEM model were introduced to simulation the second by second vehicle emission rate on real world by taking a light-duty diesel car as a case. On-board test data by a portable emission measurement system were then used to validate the simulation results. Test emission factors of CO, THC, NO(x) and CO2 were respectively 0.81, 0.61, 2.09, and 193 g x km(-1), while calculated emission factors were 0.75, 0.47, 2.47, and 212 g x km(-1). The correlation coefficients reached 0.69, 0.69, 0.75, and 0.72. Simulated instantaneous emissions of the light duty diesel vehicle by CMEM model were strongly coherent with the transient driving cycle. By analysis, CO, THC, NO(x), and CO2 emissions would be reduced by 50%, 47%, 45%, and 44% after improving the traffic situation at the intersection. The result indicated that it is necessary and feasible to simulate the instantaneous emissions of mixed vehicle fleet in some typical traffic areas by the micro-scale vehicle emission model.

  17. Sensitivity Analysis of Launch Vehicle Debris Risk Model

    Science.gov (United States)

    Gee, Ken; Lawrence, Scott L.

    2010-01-01

    As part of an analysis of the loss of crew risk associated with an ascent abort system for a manned launch vehicle, a model was developed to predict the impact risk of the debris resulting from an explosion of the launch vehicle on the crew module. The model consisted of a debris catalog describing the number, size and imparted velocity of each piece of debris, a method to compute the trajectories of the debris and a method to calculate the impact risk given the abort trajectory of the crew module. The model provided a point estimate of the strike probability as a function of the debris catalog, the time of abort and the delay time between the abort and destruction of the launch vehicle. A study was conducted to determine the sensitivity of the strike probability to the various model input parameters and to develop a response surface model for use in the sensitivity analysis of the overall ascent abort risk model. The results of the sensitivity analysis and the response surface model are presented in this paper.

  18. Stochastic Optimal Control of Parallel Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Feiyan Qin

    2017-02-01

    Full Text Available Energy management strategies (EMSs in hybrid electric vehicles (HEVs are highly related to the fuel economy and emission performances. However, EMS constitutes a challenging problem due to the complex structure of a HEV and the unknown or partially known driving cycles. To meet this problem, this paper adopts a stochastic dynamic programming (SDP method for the EMS of a specially designed vehicle, a pre-transmission single-shaft torque-coupling parallel HEV. In this parallel HEV, the auto clutch output is connected to the transmission input through an electric motor, which benefits an efficient motor assist operation. In this EMS, demanded torque of driver is modeled as a one-state Markov process to represent the uncertainty of future driving situations. The obtained EMS has been evaluated with ADVISOR2002 over two standard government drive cycles and a self-defined one, and compared with a dynamic programming (DP one and a rule-based one. Simulation results have shown the real-time performance of the proposed approach, and potential vehicle performance improvement relative to the rule-based one.

  19. Development of an in-vehicle intersection collision countermeasure

    Science.gov (United States)

    Pierowicz, John A.

    1997-02-01

    Intersection collisions constitute approximately twenty-six percent of all accidents in the United States. Because of their complexity, and demands on the perceptual and decision making abilities of the driver, intersections present an increased risk of collisions between automobiles. This situation provides an opportunity to apply advanced sensor and processing capabilities to prevent these collisions. A program to determine the characteristics of intersection collisions and identify potential countermeasures will be described. This program, sponsored by the National Highway Traffic Safety Administration, utilized accident data to develop a taxonomy of intersection crashes. This taxonomy was used to develop a concept for an intersection collision avoidance countermeasure. The concept utilizes in-vehicle position, dynamic status, and millimeter wave radar system and an in-vehicle computer system to provide inputs to an intersection collision avoidance algorithm. Detection of potential violation of traffic control device, or proceeding into the intersection with inadequate gap will lead to the presentation of a warning to the driver. These warnings are presented to the driver primarily via a head-up display and haptic feedback. Roadside to vehicle communication provides information regarding phased traffic signal information. Active control of the vehicle's brake and steering systems are described. Progress in the development of the systems will be presented along with the schedule of future activities.

  20. Simulation of electric vehicles with hybrid power systems

    Science.gov (United States)

    Burke, A. F.; Cole, G. H.

    Computer programs for the simulation of the operation of electric vehicles with hybrid power systems are described. These programs treat cases in which high energy density ultracapacitors or high power density pulse batteries are used to load level the main energy storage battery in the vehicle. A generalized control strategy for splitting the power between the main battery and the pulse power devices is implemented such that the user can specify the nominal battery power as a function of the state-of-charge of the ultracapacitor or pulse power battery. The programs display graphically on the screen, as they run, the power from both the main battery and the pulse power device and the state-of-charge of the pulse power device. After each run is completed, a summary is printed out from which the effect of load leveling the battery on vehicle range and energy consumption can be determined. Default input files are provided with the programs so various combinations of vehicles, driveline components, and batteries of special current interest to the EV community can be run with either type of pulse power device. Typical simulation results are shown including cases in which the pulse power devices are connected in parallel with the main battery without interface electronics.

  1. Habitable Mars Ascent Vehicle (MAV) Concept. [Mars Ascent Vehicle (MAV) Layout and Configuration: 6-Crew, Habitable, Nested Tank Concept

    Science.gov (United States)

    Dang, Victor; Rucker, Michelle

    2013-01-01

    NASA's ultimate goal is the human exploration of Mars. Among the many difficult aspects of a trip to Mars is the return mission that would transport the astronauts from the Martian surface back into Mars orbit. One possible conceptual design to accomplish this task is a two-stage Mars Ascent Vehicle (MAV). In order to assess this design, a general layout and configuration for the spacecraft must be developed. The objective of my internship was to model a conceptual MAV design to support NASA's latest human Mars mission architecture trade studies, technology prioritization decisions, and mass, cost, and schedule estimates.

  2. Liveness-Based RRT Algorithm for Autonomous Underwater Vehicles Motion Planning

    Directory of Open Access Journals (Sweden)

    Yang Li

    2017-01-01

    Full Text Available Motion planning is a crucial, basic issue in robotics, which aims at driving vehicles or robots towards to a given destination with various constraints, such as obstacles and limited resource. This paper presents a new version of rapidly exploring random trees (RRT, that is, liveness-based RRT (Li-RRT, to address autonomous underwater vehicles (AUVs motion problem. Different from typical RRT, we define an index of each node in the random searching tree, called “liveness” in this paper, to describe the potential effectiveness during the expanding process. We show that Li-RRT is provably probabilistic completeness as original RRT. In addition, the expected time of returning a valid path with Li-RRT is obviously reduced. To verify the efficiency of our algorithm, numerical experiments are carried out in this paper.

  3. Tracking Controller Design for Diving Behavior of an Unmanned Underwater Vehicle

    Directory of Open Access Journals (Sweden)

    Yi-Hsiang Tseng

    2013-01-01

    Full Text Available The study has investigated the almost disturbance decoupling problem of nonlinear uncertain control systems via the fuzzy feedback linearization approach. The significant dedication of this paper is to organize a control algorithm such that the closed-loop system is active for given initial condition and bounded tracking trajectory with the input-to-state stability and almost disturbance decoupling performance. This study presents a feedback linearization controller for diving control of an unmanned underwater vehicle. Unmanned underwater vehicle proposes difficult control subject due to its nonlinear dynamics, uncertain models, and the existence of disturbances that are difficult to measure. In general, while investigating the diving dynamics of an unmanned underwater vehicle, the pitch angle is always assumed to be small. This assumption is a strong restricting constraint in many interesting practical applications and will be relaxed in this study.

  4. Numerical and Engine Cycle Analyses of a Pulse Laser Ramjet Vehicle

    Science.gov (United States)

    Katsurayama, Hiroshi; Komurasaki, Kimiya; Momozawa, Ai; Arakawa, Yoshihiro

    A preliminary feasibility study of a laser ramjet SSTO has been conducted using engine cycle analysis. Although a large amount of laser energy is lost due to chemically frozen flow at high altitudes, the laser ramjet SSTO was found to be feasible with 100 MW laser power for 100 kg vehicle mass and 1 m2 vehicle cross-section area. Obtained momentum coupling coefficient, Cm, was validated by means of CFD. As a result, the engine cycle analysis was under-estimating Cm. This would be because of the strong unsteady energy input in the actual heating process and the spatially localized pressure on the afterbody.

  5. Android App Based Vehicle Tracking Using GPS And GSM

    Directory of Open Access Journals (Sweden)

    Jessica Saini

    2017-09-01

    Full Text Available Global Positioning System GPS is used in numerous applications in todays world. A real time vehicle tracking system using the GPS technology is proposed in this paper. The project Android App based Vehicle Tracking Using GSM AND GPRS mainly focuses in tracking the location of the vehicle on which the device has been installed. It will then send the data in the form of latitude and longitude coordinates through SMS on the users mobile where the coordinates will be plotted in the Android app automatically. Initially the GPS installed in the device takes input from the satellite and stores it in the microcontrollers buffer. In order to track the vehicle the mobile user has to call on the SIM number that is registered in the GSM module of the device. Once the call is received the device authenticates the calling number. If authenticated the location of the vehicle is sent to the registered mobile number in the form of SMS. After sending the message the GSM is deactivated and the GPS is activated again. The coordinates of the location received in the SMS can be viewed on the android app. The hardware part described in the paper comprises of GPRS GSM module LCD to view the coordinates ATMega Microcontroller MAX 232 Arduino RS232 and relay.

  6. On-demand high-capacity ride-sharing via dynamic trip-vehicle assignment.

    Science.gov (United States)

    Alonso-Mora, Javier; Samaranayake, Samitha; Wallar, Alex; Frazzoli, Emilio; Rus, Daniela

    2017-01-17

    Ride-sharing services are transforming urban mobility by providing timely and convenient transportation to anybody, anywhere, and anytime. These services present enormous potential for positive societal impacts with respect to pollution, energy consumption, congestion, etc. Current mathematical models, however, do not fully address the potential of ride-sharing. Recently, a large-scale study highlighted some of the benefits of car pooling but was limited to static routes with two riders per vehicle (optimally) or three (with heuristics). We present a more general mathematical model for real-time high-capacity ride-sharing that (i) scales to large numbers of passengers and trips and (ii) dynamically generates optimal routes with respect to online demand and vehicle locations. The algorithm starts from a greedy assignment and improves it through a constrained optimization, quickly returning solutions of good quality and converging to the optimal assignment over time. We quantify experimentally the tradeoff between fleet size, capacity, waiting time, travel delay, and operational costs for low- to medium-capacity vehicles, such as taxis and van shuttles. The algorithm is validated with ∼3 million rides extracted from the New York City taxicab public dataset. Our experimental study considers ride-sharing with rider capacity of up to 10 simultaneous passengers per vehicle. The algorithm applies to fleets of autonomous vehicles and also incorporates rebalancing of idling vehicles to areas of high demand. This framework is general and can be used for many real-time multivehicle, multitask assignment problems.

  7. Vehicle Modeling for use in the CAFE model: Process description and modeling assumptions

    Energy Technology Data Exchange (ETDEWEB)

    Moawad, Ayman [Argonne National Lab. (ANL), Argonne, IL (United States); Kim, Namdoo [Argonne National Lab. (ANL), Argonne, IL (United States); Rousseau, Aymeric [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-06-01

    The objective of this project is to develop and demonstrate a process that, at a minimum, provides more robust information that can be used to calibrate inputs applicable under the CAFE model’s existing structure. The project will be more fully successful if a process can be developed that minimizes the need for decision trees and replaces the synergy factors by inputs provided directly from a vehicle simulation tool. The report provides a description of the process that was developed by Argonne National Laboratory and implemented in Autonomie.

  8. Vehicle electrical system state controller

    Science.gov (United States)

    Bissontz, Jay E.

    2017-10-17

    A motor vehicle electrical power distribution system includes a plurality of distribution sub-systems, an electrical power storage sub-system and a plurality of switching devices for selective connection of elements of and loads on the power distribution system to the electrical power storage sub-system. A state transition initiator provides inputs to control system operation of switching devices to change the states of the power distribution system. The state transition initiator has a plurality of positions selection of which can initiate a state transition. The state transition initiator can emulate a four position rotary ignition switch. Fail safe power cutoff switches provide high voltage switching device protection.

  9. Cost-Effectiveness of Emissions Reduction through Vehicle Repair Compared to CNG Conversion.

    Science.gov (United States)

    Guenther, Paul L; Lesko, Jon M; Stedman, Donald H

    1996-10-01

    In return for a temporary waiver from converting five vehicles to operate on compressed natural gas (CNG) for the Denver Clean Fuels program, the University of Denver identified, tested, repaired, and retested nine employee commuter vehicles. The results of the study validated the concept that employer-based identification and repair programs can be carried out in a cost-effective way. On average, each repaired vehicle removed fifty times more carbon monoxide (CO) emissions from Denver air than each CNG conversion. The average cost of each repair was eight times less than the average cost of each conversion. The average fuel economy benefit from the repairs was enough to pay for the average cost of repairs in less than three years of normal driving. When the expected lifetimes of repairs and conversions are included, the targeted repair program appears to be over sixty times more cost-effective as a CO emissions reduction strategy than CNG conversion.

  10. ELECTROMAGNETIC BIOSPHERE POLLUTION BY MOTOR TRANSPORT (VEHICLES, ELECTRIC VEHICLES, HYBRID VEHICLES

    Directory of Open Access Journals (Sweden)

    S. Selivanov

    2009-01-01

    Full Text Available The physics of the electromagnetic field is considered. The analysis of electromagnetic radiation on the human-being, the origin of which is the vehicle the electric vehicle, the hybrid vehicle is being considered. The monitoring of electromagnetic radiation of vehicles is carried out.

  11. Measuring Aerosols Generated Inside Armoured Vehicles Perforated by Depleted Uranium Ammunition

    International Nuclear Information System (INIS)

    Parkhurst, MaryAnn

    2003-01-01

    In response to questions raised after the Gulf War about the health significance of exposure to depleted uranium (DU), the U.S. Department of Defense initiated a study designed to provide an improved scientific basis for assessment of possible health effects of soldiers in vehicles struck by these munitions. As part of this study, a series of DU penetrators were fired at an Abrams tank and a Bradley fighting vehicle, and the aerosols generated by vehicle perforation were collected and characterized. A robust sampling system was designed to collect aerosols in this difficult environment and to monitor continuously the sampler flow rates. Interior aerosols collected were analyzed for uranium concentration and particle size distribution as a function of time. They were also analyzed for uranium oxide phases, particle morphology, and dissolution in vitro. These data will provide input for future prospective and retrospective dose and health risk assessments of inhaled or ingested DU aerosols. This paper briefly discusses the target vehicles, firing trajectories, aerosol samplers and instrumentation control systems, and the types of analyses conducted on the samples

  12. Loft: An Automated Mesh Generator for Stiffened Shell Aerospace Vehicles

    Science.gov (United States)

    Eldred, Lloyd B.

    2011-01-01

    Loft is an automated mesh generation code that is designed for aerospace vehicle structures. From user input, Loft generates meshes for wings, noses, tanks, fuselage sections, thrust structures, and so on. As a mesh is generated, each element is assigned properties to mark the part of the vehicle with which it is associated. This property assignment is an extremely powerful feature that enables detailed analysis tasks, such as load application and structural sizing. This report is presented in two parts. The first part is an overview of the code and its applications. The modeling approach that was used to create the finite element meshes is described. Several applications of the code are demonstrated, including a Next Generation Launch Technology (NGLT) wing-sizing study, a lunar lander stage study, a launch vehicle shroud shape study, and a two-stage-to-orbit (TSTO) orbiter. Part two of the report is the program user manual. The manual includes in-depth tutorials and a complete command reference.

  13. Input Selection for Return Temperature Estimation in Mixing Loops using Partial Mutual Information with Flow Variable Delay

    DEFF Research Database (Denmark)

    Overgaard, Anders; Kallesøe, Carsten Skovmose; Bendtsen, Jan Dimon

    2017-01-01

    adgang til data, er ønsker at skabe en datadreven model til kontrol. Grundet den store mængde tilgængelig data anvendes der en metode til valg af inputs kaldet "Partial Mutual Information" (PMI). Denne artikel introducerer en metode til at inkluderer flow variable forsinkelser i PMI. Data fra en...... kontorbygning i Bjerringbro anvendes til analyse. Det vises at "Mutual Information" og et "Generalized Regression Neural Network" begge forbedres ved at anvende flow variabelt forsinkelse i forhold til at anvende konstante delay....

  14. A novel technique for optimal integration of active steering and differential braking with estimation to improve vehicle directional stability.

    Science.gov (United States)

    Mirzaeinejad, Hossein; Mirzaei, Mehdi; Rafatnia, Sadra

    2018-06-11

    This study deals with the enhancement of directional stability of vehicle which turns with high speeds on various road conditions using integrated active steering and differential braking systems. In this respect, the minimum usage of intentional asymmetric braking force to compensate the drawbacks of active steering control with small reduction of vehicle longitudinal speed is desired. To this aim, a new optimal multivariable controller is analytically developed for integrated steering and braking systems based on the prediction of vehicle nonlinear responses. A fuzzy programming extracted from the nonlinear phase plane analysis is also used for managing the two control inputs in various driving conditions. With the proposed fuzzy programming, the weight factors of the control inputs are automatically tuned and softly changed. In order to simulate a real-world control system, some required information about the system states and parameters which cannot be directly measured, are estimated using the Unscented Kalman Filter (UKF). Finally, simulations studies are carried out using a validated vehicle model to show the effectiveness of the proposed integrated control system in the presence of model uncertainties and estimation errors. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  15. The Library as Strategic Investment: Results of the Illinois Return on Investment Study

    Directory of Open Access Journals (Sweden)

    Paula T. Kaufman

    2008-11-01

    Full Text Available University administrators are asking library directors to demonstrate their library's value to the institution in easily articulated quantitative terms that focus on outputs rather than on traditionally reported input measures. This paper reports on a study undertaken at the University of Illinois at Urbana-Champaign that sought to measure the return on the university's investment in its library. The study sought to develop a quantitative measure that recognizes the library's value in supporting the university's strategic goals, using grant income generated by faculty using library materials. It also sought to confirm the benefits of using electronic resources and the resulting impact on productivity over a 10-year period. The results of this study, which is believed to be the first of its kind, represent only one piece of the answer to the challenge of representing the university's total return from its investment in its library.

  16. Detection of vehicle parts based on Faster R-CNN and relative position information

    Science.gov (United States)

    Zhang, Mingwen; Sang, Nong; Chen, Youbin; Gao, Changxin; Wang, Yongzhong

    2018-03-01

    Detection and recognition of vehicles are two essential tasks in intelligent transportation system (ITS). Currently, a prevalent method is to detect vehicle body, logo or license plate at first, and then recognize them. So the detection task is the most basic, but also the most important work. Besides the logo and license plate, some other parts, such as vehicle face, lamp, windshield and rearview mirror, are also key parts which can reflect the characteristics of vehicle and be used to improve the accuracy of recognition task. In this paper, the detection of vehicle parts is studied, and the work is novel. We choose Faster R-CNN as the basic algorithm, and take the local area of an image where vehicle body locates as input, then can get multiple bounding boxes with their own scores. If the box with maximum score is chosen as final result directly, it is often not the best one, especially for small objects. This paper presents a method which corrects original score with relative position information between two parts. Then we choose the box with maximum comprehensive score as the final result. Compared with original output strategy, the proposed method performs better.

  17. Energy-Efficient Cooperative Techniques for Infrastructure-to-Vehicle Communications

    OpenAIRE

    Nguyen , Tuan-Duc; Berder , Olivier; Sentieys , Olivier

    2011-01-01

    International audience; In wireless distributed networks, cooperative relay and cooperative Multi-Input Multi-Output (MIMO) techniques can be used to exploit the spatial and temporal diversity gain in order to increase the performance or reduce the transmission energy consumption. The energy efficiency of cooperative MIMO and relay techniques is then very useful for the Infrastructure to Vehicle (I2V) and Infrastructure to Infrastructure (I2I) communications in Intelligent Transport Systems (I...

  18. Statistical models of petrol engines vehicles dynamics

    Science.gov (United States)

    Ilie, C. O.; Marinescu, M.; Alexa, O.; Vilău, R.; Grosu, D.

    2017-10-01

    This paper focuses on studying statistical models of vehicles dynamics. It was design and perform a one year testing program. There were used many same type cars with gasoline engines and different mileage. Experimental data were collected of onboard sensors and those on the engine test stand. A database containing data of 64th tests was created. Several mathematical modelling were developed using database and the system identification method. Each modelling is a SISO or a MISO linear predictive ARMAX (AutoRegressive-Moving-Average with eXogenous inputs) model. It represents a differential equation with constant coefficients. It were made 64th equations for each dependency like engine torque as output and engine’s load and intake manifold pressure, as inputs. There were obtained strings with 64 values for each type of model. The final models were obtained using average values of the coefficients. The accuracy of models was assessed.

  19. EFISIENSI PERBANKAN DI INDONESIA DAN PENGARUHNYA TERHADAP RETURN SAHAM DENGAN PENDEKATAN DATA ENVELOPMENT ANALYSIS ( DEA

    Directory of Open Access Journals (Sweden)

    Rina Sari Qurniawati

    2014-06-01

    Full Text Available The purpose of this study was to analyze bank efficiency listed in Indonesia Stock Exchange (IDX and to empirically determine the effect of bank efficiency listed in BEI toward stock performance reflected in stock returns. The sampling is bank listed in IDX from 2004 until 2008. DEA is used to measure the bank efficiency from each Decision Making Units  (DMUs,which is obtained as the maximum weight ratio of outputs and inputs. The result of banks efficiency using DEA approach indicated that most of Bank in Indonesia is efficient. Only 6 banks from 16 banks which have not yet reached the efficiency score over the 5 years. Meanwhile, the regression test did not revealed any effect of the bank efficiency in Indonesia toward stock return.

  20. Design of a Path-Tracking Steering Controller for Autonomous Vehicles

    Directory of Open Access Journals (Sweden)

    Chuanyang Sun

    2018-06-01

    Full Text Available This paper presents a linearization method for the vehicle and tire models under the model predictive control (MPC scheme, and proposes a linear model-based MPC path-tracking steering controller for autonomous vehicles. The steering controller is designed to minimize lateral path-tracking deviation at high speeds. The vehicle model is linearized by a sequence of supposed steering angles, which are obtained by assuming the vehicle can reach the desired path at the end of the MPC prediction horizon and stay in a steady-state condition. The lateral force of the front tire is directly used as the control input of the model, and the rear tire’s lateral force is linearized by an equivalent cornering stiffness. The course-direction deviation, which is the angle between the velocity vector and the path heading, is chosen as a control reference state. The linearization model is validated through the simulation, and the results show high prediction accuracy even in regions of large steering angle. This steering controller is tested through simulations on the CarSim-Simulink platform (R2013b, MathWorks, Natick, MA, USA, showing the improved performance of the present controller at high speeds.

  1. TART input manual

    International Nuclear Information System (INIS)

    Kimlinger, J.R.; Plechaty, E.F.

    1982-01-01

    The TART code is a Monte Carlo neutron/photon transport code that is only on the CRAY computer. All the input cards for the TART code are listed, and definitions for all input parameters are given. The execution and limitations of the code are described, and input for two sample problems are given

  2. Proof of Concept of Home IoT Connected Vehicles

    Science.gov (United States)

    Kim, Younsun; Oh, Hyunggoy; Kang, Sungho

    2017-01-01

    The way in which we interact with our cars is changing, driven by the increased use of mobile devices, cloud-based services, and advanced automotive technology. In particular, the requirements and market demand for the Internet of Things (IoT) device-connected vehicles will continuously increase. In addition, the advances in cloud computing and IoT have provided a promising opportunity for developing vehicular software and services in the automotive domain. In this paper, we introduce the concept of a home IoT connected vehicle with a voice-based virtual personal assistant comprised of a vehicle agent and a home agent. The proposed concept is evaluated by implementing a smartphone linked with home IoT devices that are connected to an infotainment system for the vehicle, a smartphone-based natural language interface input device, and cloud-based home IoT devices for the home. The home-to-vehicle connected service scenarios that aim to reduce the inconvenience due to simple and repetitive tasks by improving the urban mobility efficiency in IoT environments are substantiated by analyzing real vehicle testing and lifestyle research. Remarkable benefits are derived by making repetitive routine tasks one task that is executed by a command and by executing essential tasks automatically, without any request. However, it should be used with authorized permission, applied without any error at the right time, and applied under limited conditions to sense the habitants’ intention correctly and to gain the required trust regarding the remote execution of tasks. PMID:28587246

  3. Proof of Concept of Home IoT Connected Vehicles.

    Science.gov (United States)

    Kim, Younsun; Oh, Hyunggoy; Kang, Sungho

    2017-06-05

    The way in which we interact with our cars is changing, driven by the increased use of mobile devices, cloud-based services, and advanced automotive technology. In particular, the requirements and market demand for the Internet of Things (IoT) device-connected vehicles will continuously increase. In addition, the advances in cloud computing and IoT have provided a promising opportunity for developing vehicular software and services in the automotive domain. In this paper, we introduce the concept of a home IoT connected vehicle with a voice-based virtual personal assistant comprised of a vehicle agent and a home agent. The proposed concept is evaluated by implementing a smartphone linked with home IoT devices that are connected to an infotainment system for the vehicle, a smartphone-based natural language interface input device, and cloud-based home IoT devices for the home. The home-to-vehicle connected service scenarios that aim to reduce the inconvenience due to simple and repetitive tasks by improving the urban mobility efficiency in IoT environments are substantiated by analyzing real vehicle testing and lifestyle research. Remarkable benefits are derived by making repetitive routine tasks one task that is executed by a command and by executing essential tasks automatically, without any request. However, it should be used with authorized permission, applied without any error at the right time, and applied under limited conditions to sense the habitants' intention correctly and to gain the required trust regarding the remote execution of tasks.

  4. Parameter Estimation and Verification of Unmanned Air Cushion Vehicle (UACV System

    Directory of Open Access Journals (Sweden)

    Ab Rashid Mohd Zamzuri

    2017-01-01

    Full Text Available This project is mainly about the dynamic modelling and parameter estimation of Unmanned Air Cushion Vehicle (UACV. The purpose of developing mathematical model of the Unmanned Air Cushion Vehicle (UACV is due to its under actuated nonlinearities where it has less input compared to the output required. This system able to maneuver over land, water and other surfaces either at certain speed or maintain at a stationary position. In order to model the UACV, the system is set to have two propellers which are responsible to lift the vehicle by forcing high pressure air under the system. The air inflates the “skirt” under the vehicle, causing it to rise above the surface while another two propellers are used to steer the UACV forward. UACV system can be considered as under actuated since it possess fewer controller inputs that its degree of freedom. The system’s motions are defined by the six degrees of freedom which are; heaved, sway and surge. Another three components are rotational motions which can be elaborated as roll, pitch and yaw. The problem related to UACV is normally related to obtaining accurate parameters of the system to be included into the mathematical model of the system. This is due to the body inertia of the system during the static and moving condition. Besides, the air that flows into the UACV skirt to create the cushion causes imbalance and will affect the system stability and controllability. In this research, UACV need to be mathematically modelled using Euler-Lagrange method. Then, parameters of the system can be obtained through direct calculation and Solidworks software. The parameters acquired are compared and verified using simulation and experimental studies.

  5. UNMANNED AIR VEHICLE STABILIZATION BASED ON NEURAL NETWORK REGULATOR

    Directory of Open Access Journals (Sweden)

    S. S. Andropov

    2016-09-01

    Full Text Available A problem of stabilizing for the multirotor unmanned aerial vehicle in an environment with external disturbances is researched. A classic proportional-integral-derivative controller is analyzed, its flaws are outlined: inability to respond to changing of external conditions and the need for manual adjustment of coefficients. The paper presents an adaptive adjustment method for coefficients of the proportional-integral-derivative controller based on neural networks. A neural network structure, its input and output data are described. Neural networks with three layers are used to create an adaptive stabilization system for the multirotor unmanned aerial vehicle. Training of the networks is done with the back propagation method. Each neural network produces regulator coefficients for each angle of stabilization as its output. A method for network training is explained. Several graphs of transition process on different stages of learning, including processes with external disturbances, are presented. It is shown that the system meets stabilization requirements with sufficient number of iterations. Described adjustment method for coefficients can be used in remote control of unmanned aerial vehicles, operating in the changing environment.

  6. Design and characterization of axial flux permanent magnet energy harvester for vehicle magnetorheological damper

    International Nuclear Information System (INIS)

    Dong, Xiaomin

    2016-01-01

    An axial flux permanent magnet energy harvester (AFPMEH) is proposed and analyzed for a vehicle magneto-rheological (MR) damper. The relationship between the output voltage and the input excitations are analytically developed. Under different constant rotation speeds and sinusoidal excitations, the harvesting energy is numerically computed for different loads of pure resistance and coil in the MR damper. To check the performance of the proposed AFPMEH for the MR damper, the AFPMEH and MR damper are fabricated individually. Experiments are performed to measure the harvesting energy of the AFPMEH and the damping characteristics of the MR damper under different excited conditions. The excited conditions include three constant rotation speeds and sinusoidal inputs. Load inputs of the pure resistance and the coil of the MR damper are considered. The results show that the time history of the generated voltage of the AFPMEH in experiment is agreed well with that of the AFPMEH in simulation. Under constant rotation speeds, the root mean square (rms) of loaded voltage will increase with the increment of load, whereas the rms of power will be affected by the amplitude of load. The MR damper powered by the AFPMEH can almost obtain the similar damping characteristics of that external power supply. Under sinusoidal inputs, the rms of loaded voltage will increase with the increment of external loads, whereas the rms of power will be almost kept as a constant. The damping range of the MR damper can also be enlarged over 30% comparing to off-state damping force. A quarter car model with an MR damper powered by the AFPMEH is developed to investigate the control performance. The on–off skyhook control is adopted to tune the input current of the MR damper. The vibration performance of the MR suspension is investigated under different roads and vehicle speeds. The numerical results show that the MR suspension with the AFPMEH under on–off skyhook control can achieve better ride

  7. Electrification Beyond Light Duty: Class 2b-3 Commercial Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Birky, Alicia [Energetics Incorporated; Laughlin, Michael [Energetics Incorporated; Tartaglia, Katie [Energetics Incorporated; Price, Rebecca [Energetics Incorporated; Lim, Brandon [Energetics Incorporated; Lin, Zhenhong [ORNL

    2018-01-01

    The class 2b-3 truck market covers a wide range of commercial truck applications across a half-million vehicle sales annually. This report collected public information and stakeholder input to assess the opportunity for electrification in this market. Although class 2b-3 pickup truck and van bodies are very similar to personal light vehicles, their functional requirements are quite different due to the demands of the commercial market. These demands vary by application and often vary from day to day for a single application. Fleet customers purchase these vehicles to perform a particular job for their business and are concerned about the overall cost of doing that job. Therefore, the vehicles must meet the job requirements cost effectively. Customers also are sensitive to initial cost. Electrification offers the potential to reduce vehicle operating costs and possibly improve vehicle functionality. However, the current market for class 2b-3 electrified trucks is very small, and the trucks are costly. Increased production volumes are key to cost reductions and may be assisted by sharing components with larger or smaller truck classes. Expanding demand is also crucial and stakeholders identified several niche markets with duty cycles that are likely well-suited to electrified class 2b-3 trucks. To expand beyond these niches, class 2b-3 electric solutions must be robust, flexible, and adaptable in order to cover a wide range of vocations, applications, and duty cycles.

  8. To twist or poke? A method for identifying usability issues with the rotary controller and touch screen for control of in-vehicle information systems.

    Science.gov (United States)

    Harvey, Catherine; Stanton, Neville A; Pickering, Carl A; McDonald, Mike; Zheng, Pengjun

    2011-07-01

    In-vehicle information systems (IVIS) can be controlled by the user via direct or indirect input devices. In order to develop the next generation of usable IVIS, designers need to be able to evaluate and understand the usability issues associated with these two input types. The aim of this study was to investigate the effectiveness of a set of empirical usability evaluation methods for identifying important usability issues and distinguishing between the IVIS input devices. A number of usability issues were identified and their causal factors have been explored. These were related to the input type, the structure of the menu/tasks and hardware issues. In particular, the translation between inputs and on-screen actions and a lack of visual feedback for menu navigation resulted in lower levels of usability for the indirect device. This information will be useful in informing the design of new IVIS, with improved usability. STATEMENT OF RELEVANCE: This paper examines the use of empirical methods for distinguishing between direct and indirect IVIS input devices and identifying usability issues. Results have shown that the characteristics of indirect input devices produce more serious usability issues, compared with direct devices and can have a negative effect on the driver-vehicle interaction.

  9. Structural weights analysis of advanced aerospace vehicles using finite element analysis

    Science.gov (United States)

    Bush, Lance B.; Lentz, Christopher A.; Rehder, John J.; Naftel, J. Chris; Cerro, Jeffrey A.

    1989-01-01

    A conceptual/preliminary level structural design system has been developed for structural integrity analysis and weight estimation of advanced space transportation vehicles. The system includes a three-dimensional interactive geometry modeler, a finite element pre- and post-processor, a finite element analyzer, and a structural sizing program. Inputs to the system include the geometry, surface temperature, material constants, construction methods, and aerodynamic and inertial loads. The results are a sized vehicle structure capable of withstanding the static loads incurred during assembly, transportation, operations, and missions, and a corresponding structural weight. An analysis of the Space Shuttle external tank is included in this paper as a validation and benchmark case of the system.

  10. Studsvik's implementation of the DOE spent fuel return program: The US perspective

    International Nuclear Information System (INIS)

    Grover, Stephen; Browser, Rita C.

    1996-01-01

    The government of Sweden has long been a proponent of nuclear nonproliferation policies. This includes laws governing the conduct of the Studsvik R2 Reactor in Nykoeping, Sweden. Studsvik became a participant in the RERTR program early on and was one of the first research reactors to convert from Highly Enriched Uranium (HEU) to Low Enriched Uranium (LEU) fuel. Since Studsvik operates the reactor on a commercial basis, it is important to fully comply with all Swedish laws and regulations for the operation of a nuclear reactor. This includes development of a proper long term program for the final disposition for the irradiated fuel. For this reason it was very important to Studsvik to be involved in the process for development of the DOE Spent Fuel Return Program as early as possible. This process included input into the Environmental Impact Statement process, early contractual negotiations after the issuance of the Record of Decision, participation in litigation involving the Spent Fuel Return Program, and plans for return of HEU fuel on the first European shipment. Not only was program involvement important, but actual program implementation was necessary for Studsvik to maintain its reactor license. Studsvik needed to have fuel included in the first shipment in the return program not only for licensing considerations, but also to reduce the proliferation risk associated with the storage of non-self protecting fuel. To ensure participation in the first shipment, Studsvik's activities included the early development of Appendix A's, coordinating the shipment, obtaining approvals and authorizations, and other technical aspects. (author)

  11. Development of Matlab Simulink model for dynamics analysis of passive suspension system for lightweight vehicle

    Science.gov (United States)

    Jamali, M. S.; Ismail, K. A.; Taha, Z.; Aiman, M. F.

    2017-10-01

    In designing suitable isolators to reduce unwanted vibration in vehicles, the response from a mathematical model which characterizes the transmissibility ratio of the input and output of the vehicle is required. In this study, a Matlab Simulink model is developed to study the dynamic behaviour performance of passive suspension system for a lightweight electric vehicle. The Simulink model is based on the two degrees of freedom system quarter car model. The model is compared to the theoretical plots of the transmissibility ratios between the amplitudes of the displacements and accelerations of the sprung and unsprung masses to the amplitudes of the ground, against the frequencies at different damping values. It was found that the frequency responses obtained from the theoretical calculations and from the Simulink simulation is comparable to each other. Hence, the model may be extended to a full vehicle model.

  12. Accelerated Lane-Changing Trajectory Planning of Automated Vehicles with Vehicle-to-Vehicle Collaboration

    Directory of Open Access Journals (Sweden)

    Haijian Bai

    2017-01-01

    Full Text Available Considering the complexity of lane changing using automated vehicles and the frequency of turning lanes in city settings, this paper aims to generate an accelerated lane-changing trajectory using vehicle-to-vehicle collaboration (V2VC. Based on the characteristics of accelerated lane changing, we used a polynomial method and cooperative strategies for trajectory planning to establish a lane-changing model under different degrees of collaboration with the following vehicle in the target lane by considering vehicle kinematics and comfort requirements. Furthermore, considering the shortcomings of the traditional elliptical vehicle and round vehicle models, we established a rectangular vehicle model with collision boundary conditions by analysing the relationships between the possible collision points and the outline of the vehicle. Then, we established a simulation model for the accelerated lane-changing process in different environments under different degrees of collaboration. The results show that, by using V2VC, we can achieve safe accelerated lane-changing trajectories and simultaneously satisfy the requirements of vehicle kinematics and comfort control.

  13. Influence of guideway flexibility on maglev vehicle/guideway dynamic forces. Final report, July 1991-July 1992

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, L E; Ahlbeck, D R; Stekly, Z J; Gregorek, G M

    1992-07-01

    The report presents the results of a study investigating the dynamic interaction between aerial structures and maglev vehicles. The study includes three dimensional responses for attractive (EMS) maglev vehicle and repulsive (EDS) maglev vehicles and six different guideway structures. The analysis is conducted using original time domain computer models which incorporate up to 52 degrees of freedom for EMS systems and 44 degrees of freedom for the EDS systems, including multiple span guideways, multiple-vehicle trains, aerodynamic inputs with the special relations and structural properties associated with each major system component, and with appropriate maglev suspension characteristics interconnecting vehicle to guideway. The various guideway structure and vehicle combinations are analyzed separately for two representative guideway lengths of 21m and 39m. Results are presented for vehicle accelerations in terms of ride comfort accelerations and for guideway accelerations and bending moments. Comparisons from the analysis include EMS vs. EDS system responses, effects of span length, effects of position in car, effects of multiple-vehicle trains, effects of multiple simple span guideways vs. continuous span guideways, effects of wind gusts, and effects of beam bearing pad stiffness. Costs of each guideway is estimated in 1992 dollars.

  14. Self-tuning control algorithm design for vehicle adaptive cruise control system through real-time estimation of vehicle parameters and road grade

    Science.gov (United States)

    Marzbanrad, Javad; Tahbaz-zadeh Moghaddam, Iman

    2016-09-01

    The main purpose of this paper is to design a self-tuning control algorithm for an adaptive cruise control (ACC) system that can adapt its behaviour to variations of vehicle dynamics and uncertain road grade. To this aim, short-time linear quadratic form (STLQF) estimation technique is developed so as to track simultaneously the trend of the time-varying parameters of vehicle longitudinal dynamics with a small delay. These parameters are vehicle mass, road grade and aerodynamic drag-area coefficient. Next, the values of estimated parameters are used to tune the throttle and brake control inputs and to regulate the throttle/brake switching logic that governs the throttle and brake switching. The performance of the designed STLQF-based self-tuning control (STLQF-STC) algorithm for ACC system is compared with the conventional method based on fixed control structure regarding the speed/distance tracking control modes. Simulation results show that the proposed control algorithm improves the performance of throttle and brake controllers, providing more comfort while travelling, enhancing driving safety and giving a satisfactory performance in the presence of different payloads and road grade variations.

  15. Selection Input Output by Restriction Using DEA Models Based on a Fuzzy Delphi Approach and Expert Information

    Science.gov (United States)

    Arsad, Roslah; Nasir Abdullah, Mohammad; Alias, Suriana; Isa, Zaidi

    2017-09-01

    Stock evaluation has always been an interesting problem for investors. In this paper, a comparison regarding the efficiency stocks of listed companies in Bursa Malaysia were made through the application of estimation method of Data Envelopment Analysis (DEA). One of the interesting research subjects in DEA is the selection of appropriate input and output parameter. In this study, DEA was used to measure efficiency of stocks of listed companies in Bursa Malaysia in terms of the financial ratio to evaluate performance of stocks. Based on previous studies and Fuzzy Delphi Method (FDM), the most important financial ratio was selected. The results indicated that return on equity, return on assets, net profit margin, operating profit margin, earnings per share, price to earnings and debt to equity were the most important ratios. Using expert information, all the parameter were clarified as inputs and outputs. The main objectives were to identify most critical financial ratio, clarify them based on expert information and compute the relative efficiency scores of stocks as well as rank them in the construction industry and material completely. The methods of analysis using Alirezaee and Afsharian’s model were employed in this study, where the originality of Charnes, Cooper and Rhodes (CCR) with the assumption of Constant Return to Scale (CSR) still holds. This method of ranking relative efficiency of decision making units (DMUs) was value-added by the Balance Index. The interested data was made for year 2015 and the population of the research includes accepted companies in stock markets in the construction industry and material (63 companies). According to the ranking, the proposed model can rank completely for 63 companies using selected financial ratio.

  16. Predictability of Stock Returns

    Directory of Open Access Journals (Sweden)

    Ahmet Sekreter

    2017-06-01

    Full Text Available Predictability of stock returns has been shown by empirical studies over time. This article collects the most important theories on forecasting stock returns and investigates the factors that affecting behavior of the stocks’ prices and the market as a whole. Estimation of the factors and the way of estimation are the key issues of predictability of stock returns.

  17. The real-world safety potential of connected vehicle technology.

    Science.gov (United States)

    Doecke, Sam; Grant, Alex; Anderson, Robert W G

    2015-01-01

    This article estimates the safety potential of a current commercially available connected vehicle technology in real-world crashes. Data from the Centre for Automotive Safety Research's at-scene in-depth crash investigations in South Australia were used to simulate the circumstances of real-world crashes. A total of 89 crashes were selected for inclusion in the study. The crashes were selected as representative of the most prevalent crash types for injury or fatal crashes and had potential to be mitigated by connected vehicle technology. The trajectory, speeds, braking, and impact configuration of the selected in-depth cases were replicated in a software package and converted to a file format allowing "replay" of the scenario in real time as input to 2 Cohda Wireless MK2 onboard units. The Cohda Wireless onboard units are a mature connected vehicle technology that has been used in both the German simTD field trial and the U.S. Department of Transport's Safety Pilot project and have been tuned for low false alarm rates when used in the real world. The crash replay was achieved by replacing each of the onboard unit Global Positioning System (GPS) inputs with the simulated data of each of the involved vehicles. The time at which the Cohda Wireless threat detection software issued an elevated warning was used to calculate a new impact speed using 3 different reaction scenarios and 2 levels of braking. It was found that between 37 and 86% of the simulated crashes could be avoided, with highest percentage due a fully autonomous system braking at 0.7 g. The same system also reduced the impact speed relative to the actual crash in all cases. Even when a human reaction time of 1.2 s and moderate braking of 0.4 g was assumed, the impact speed was reduced in 78% of the crashes. Crash types that proved difficult for the threat detection engine were head-on crashes where the approach angle was low and right turn-opposite crashes. These results indicate that connected vehicle

  18. Characteristic Model-Based Robust Model Predictive Control for Hypersonic Vehicles with Constraints

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    2017-06-01

    Full Text Available Designing robust control for hypersonic vehicles in reentry is difficult, due to the features of the vehicles including strong coupling, non-linearity, and multiple constraints. This paper proposed a characteristic model-based robust model predictive control (MPC for hypersonic vehicles with reentry constraints. First, the hypersonic vehicle is modeled by a characteristic model composed of a linear time-varying system and a lumped disturbance. Then, the identification data are regenerated by the accumulative sum idea in the gray theory, which weakens effects of the random noises and strengthens regularity of the identification data. Based on the regenerated data, the time-varying parameters and the disturbance are online estimated according to the gray identification. At last, the mixed H2/H∞ robust predictive control law is proposed based on linear matrix inequalities (LMIs and receding horizon optimization techniques. Using active tackling system constraints of MPC, the input and state constraints are satisfied in the closed-loop control system. The validity of the proposed control is verified theoretically according to Lyapunov theory and illustrated by simulation results.

  19. Conceptual Design and Optimal Power Control Strategy for AN Eco-Friendly Hybrid Vehicle

    Science.gov (United States)

    Nasiri, N. Mir; Chieng, Frederick T. A.

    2011-06-01

    This paper presents a new concept for a hybrid vehicle using a torque and speed splitting technique. It is implemented by the newly developed controller in combination with a two degree of freedom epicyclic gear transmission. This approach enables optimization of the power split between the less powerful electrical motor and more powerful engine while driving a car load. The power split is fundamentally a dual-energy integration mechanism as it is implemented by using the epicyclic gear transmission that has two inputs and one output for a proper power distribution. The developed power split control system manages the operation of both the inputs to have a known output with the condition of maintaining optimum operating efficiency of the internal combustion engine and electrical motor. This system has a huge potential as it is possible to integrate all the features of hybrid vehicle known to-date such as the regenerative braking system, series hybrid, parallel hybrid, series/parallel hybrid, and even complex hybrid (bidirectional). By using the new power split system it is possible to further reduce fuel consumption and increase overall efficiency.

  20. Diversification in the driveway: mean-variance optimization for greenhouse gas emissions reduction from the next generation of vehicles

    International Nuclear Information System (INIS)

    Oliver Gao, H.; Stasko, Timon H.

    2009-01-01

    Modern portfolio theory is applied to the problem of selecting which vehicle technologies and fuels to use in the next generation of vehicles. Selecting vehicles with the lowest lifetime cost is complicated by the fact that future prices are uncertain, just as selecting securities for an investment portfolio is complicated by the fact that future returns are uncertain. A quadratic program is developed based on modern portfolio theory, with the objective of minimizing the expected lifetime cost of the 'vehicle portfolio'. Constraints limit greenhouse gas emissions, as well as the variance of the cost. A case study is performed for light-duty passenger vehicles in the United States, drawing emissions and usage data from the US Environmental Protection Agency's MOVES and Department of Energy's GREET models, among other sources. Four vehicle technologies are considered: conventional gasoline, conventional diesel, grid-independent (non-plug-in) gasoline-electric hybrid, and flex fuel using E85. Results indicate that much of the uncertainty surrounding cost stems from fuel price fluctuations, and that fuel efficient vehicles can lower cost variance. Hybrids exhibit the lowest cost variances of the technologies considered, making them an arguably financially conservative choice.

  1. Diversification in the driveway: mean-variance optimization for greenhouse gas emissions reduction from the next generation of vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Oliver Gao, H.; Stasko, Timon H. [School of Civil and Environmental Engineering, Cornell University, Ithaca, NY 14853 (United States)

    2009-12-15

    Modern portfolio theory is applied to the problem of selecting which vehicle technologies and fuels to use in the next generation of vehicles. Selecting vehicles with the lowest lifetime cost is complicated by the fact that future prices are uncertain, just as selecting securities for an investment portfolio is complicated by the fact that future returns are uncertain. A quadratic program is developed based on modern portfolio theory, with the objective of minimizing the expected lifetime cost of the 'vehicle portfolio'. Constraints limit greenhouse gas emissions, as well as the variance of the cost. A case study is performed for light-duty passenger vehicles in the United States, drawing emissions and usage data from the US Environmental Protection Agency's MOVES and Department of Energy's GREET models, among other sources. Four vehicle technologies are considered: conventional gasoline, conventional diesel, grid-independent (non-plug-in) gasoline-electric hybrid, and flex fuel using E85. Results indicate that much of the uncertainty surrounding cost stems from fuel price fluctuations, and that fuel efficient vehicles can lower cost variance. Hybrids exhibit the lowest cost variances of the technologies considered, making them an arguably financially conservative choice. (author)

  2. Object-based detection of vehicles using combined optical and elevation data

    Science.gov (United States)

    Schilling, Hendrik; Bulatov, Dimitri; Middelmann, Wolfgang

    2018-02-01

    The detection of vehicles is an important and challenging topic that is relevant for many applications. In this work, we present a workflow that utilizes optical and elevation data to detect vehicles in remotely sensed urban data. This workflow consists of three consecutive stages: candidate identification, classification, and single vehicle extraction. Unlike in most previous approaches, fusion of both data sources is strongly pursued at all stages. While the first stage utilizes the fact that most man-made objects are rectangular in shape, the second and third stages employ machine learning techniques combined with specific features. The stages are designed to handle multiple sensor input, which results in a significant improvement. A detailed evaluation shows the benefits of our workflow, which includes hand-tailored features; even in comparison with classification approaches based on Convolutional Neural Networks, which are state of the art in computer vision, we could obtain a comparable or superior performance (F1 score of 0.96-0.94).

  3. Input-output supervisor

    International Nuclear Information System (INIS)

    Dupuy, R.

    1970-01-01

    The input-output supervisor is the program which monitors the flow of informations between core storage and peripheral equipments of a computer. This work is composed of three parts: 1 - Study of a generalized input-output supervisor. With sample modifications it looks like most of input-output supervisors which are running now on computers. 2 - Application of this theory on a magnetic drum. 3 - Hardware requirement for time-sharing. (author) [fr

  4. A Model Predictive Control Approach for Fuel Economy Improvement of a Series Hydraulic Hybrid Vehicle

    Directory of Open Access Journals (Sweden)

    Tri-Vien Vu

    2014-10-01

    Full Text Available This study applied a model predictive control (MPC framework to solve the cruising control problem of a series hydraulic hybrid vehicle (SHHV. The controller not only regulates vehicle velocity, but also engine torque, engine speed, and accumulator pressure to their corresponding reference values. At each time step, a quadratic programming problem is solved within a predictive horizon to obtain the optimal control inputs. The objective is to minimize the output error. This approach ensures that the components operate at high efficiency thereby improving the total efficiency of the system. The proposed SHHV control system was evaluated under urban and highway driving conditions. By handling constraints and input-output interactions, the MPC-based control system ensures that the system operates safely and efficiently. The fuel economy of the proposed control scheme shows a noticeable improvement in comparison with the PID-based system, in which three Proportional-Integral-Derivative (PID controllers are used for cruising control.

  5. The Return to Foreign Aid

    DEFF Research Database (Denmark)

    Dalgaard, Carl-Johan Lars; Hansen, Henrik

    2017-01-01

    We estimate the average rate of return on investments financed by aid and by domestic resource mobilisation, using aggregate data. Both returns are expected to vary across countries and time. Consequently we develop a correlated random coefficients model to estimate the average returns. Across...... different estimators and two different data sources for GDP and investment our findings are remarkably robust; the average gross return on ‘aid investments’ is about 20 per cent. This is in accord with micro estimates of the economic rate of return on aid projects and with aggregate estimates of the rate...

  6. Volatile organic compounds (VOCs) source profiles of on-road vehicle emissions in China.

    Science.gov (United States)

    Hong-Li, Wang; Sheng-Ao, Jing; Sheng-Rong, Lou; Qing-Yao, Hu; Li, Li; Shi-Kang, Tao; Cheng, Huang; Li-Ping, Qiao; Chang-Hong, Chen

    2017-12-31

    Volatile Organic Compounds (VOCs) source profiles of on-road vehicles were widely studied as their critical roles in VOCs source apportionment and abatement measures in megacities. Studies of VOCs source profiles from on-road motor vehicles from 2001 to 2016 were summarized in this study, with a focus on the comparisons among different studies and the potential impact of different factors. Generally, non-methane hydrocarbons dominated the source profile of on-road vehicle emissions. Carbonyls, potential important components of vehicle emission, were seldom considered in VOCs emissions of vehicles in the past and should be paid more attention to in further study. VOCs source profiles showed some variations among different studies, and 6 factors were extracted and studied due to their impact to VOCs source profile of on-road vehicles. Vehicle types, being dependent on engine types, and fuel types were two dominant factors impacting VOCs sources profiles of vehicles. In comparison, impacts of ignitions, driving conditions and accumulated mileage were mainly due to their influence on the combustion efficiency. An opening and interactive database of VOCs from vehicle emissions was critically essential in future, and mechanisms of sharing and inputting relative research results should be formed to encourage researchers join the database establishment. Correspondingly, detailed quality assurance and quality control procedures were also very important, which included the information of test vehicles and test methods as detailed as possible. Based on the community above, a better uncertainty analysis could be carried out for the VOCs emissions profiles, which was critically important to understand the VOCs emission characteristics of the vehicle emissions. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Effects of vehicle power on passenger vehicle speeds.

    Science.gov (United States)

    McCartt, Anne T; Hu, Wen

    2017-07-04

    During the past 2 decades, there have been large increases in mean horsepower and the mean horsepower-to-vehicle weight ratio for all types of new passenger vehicles in the United States. This study examined the relationship between travel speeds and vehicle power, defined as horsepower per 100 pounds of vehicle weight. Speed cameras measured travel speeds and photographed license plates and drivers of passenger vehicles traveling on roadways in Northern Virginia during daytime off-peak hours in spring 2013. The driver licensing agencies in the District of Columbia, Maryland, and Virginia provided vehicle information numbers (VINs) by matching license plate numbers with vehicle registration records and provided the age, gender, and ZIP code of the registered owner(s). VINs were decoded to obtain the curb weight and horsepower of vehicles. The study focused on 26,659 observed vehicles for which information on horsepower was available and the observed age and gender of drivers matched vehicle registration records. Log-linear regression estimated the effects of vehicle power on mean travel speeds, and logistic regression estimated the effects of vehicle power on the likelihood of a vehicle traveling over the speed limit and more than 10 mph over the limit. After controlling for driver characteristics, speed limit, vehicle type, and traffic volume, a 1-unit increase in vehicle power was associated with a 0.7% increase in mean speed, a 2.7% increase in the likelihood of a vehicle exceeding the speed limit by any amount, and an 11.6% increase in the likelihood of a vehicle exceeding the limit by 10 mph. All of these increases were highly significant. Speeding persists as a major factor in crashes in the United States. There are indications that travel speeds have increased in recent years. The current findings suggest the trend toward substantially more powerful vehicles may be contributing to higher speeds. Given the strong association between travel speed and crash

  8. Advanced APS Impacts on Vehicle Payloads

    Science.gov (United States)

    Schneider, Steven J.; Reed, Brian D.

    1989-01-01

    Advanced auxiliary propulsion system (APS) technology has the potential to both, increase the payload capability of earth-to-orbit (ETO) vehicles by reducing APS propellant mass, and simplify ground operations and logistics by reducing the number of fluids on the vehicle and eliminating toxic, corrosive propellants. The impact of integrated cryogenic APS on vehicle payloads is addressed. In this system, launch propulsion system residuals are scavenged from integral launch propulsion tanks for use in the APS. Sufficient propellant is preloaded into the APS to return to earth with margin and noncomplete scavenging assumed. No propellant conditioning is required by the APS, but ambient heat soak is accommodated. High temperature rocket materials enable the use of the unconditioned hydrogen/oxygen in the APS and are estimated to give APS rockets specific impulse of up to about 444 sec. The payload benefits are quantified and compared with an uprated monomethyl hydrazine/nitrogen tetroxide system in a conservative fashion, by assuming a 25.5 percent weight growth for the hydrogen/oxygen system and a 0 percent weight growth for the uprated system. The combination and scavenging and high performance gives payload impacts which are highly mission specific. A payload benefit of 861 kg (1898 lbm) was estimated for a Space Station Freedom rendezvous mission and 2099 kg (4626 lbm) for a sortie mission, with payload impacts varying with the amount of launch propulsion residual propellants. Missions without liquid propellant scavenging were estimated to have payload penalties, however, operational benefits were still possible.

  9. 76 FR 22611 - Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic...

    Science.gov (United States)

    2011-04-22

    ... Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic Media... Register on Wednesday, March 30, 2011 (76 FR 17521) providing guidance to specified tax return preparers who prepare and file individual income tax returns using magnetic media pursuant to section 6011(e)(3...

  10. Electric vehicle equipment for grid-integrated vehicles

    Science.gov (United States)

    Kempton, Willett

    2013-08-13

    Methods, systems, and apparatus for interfacing an electric vehicle with an electric power grid are disclosed. An exemplary apparatus may include a station communication port for interfacing with electric vehicle station equipment (EVSE), a vehicle communication port for interfacing with a vehicle management system (VMS), and a processor coupled to the station communication port and the vehicle communication port to establish communication with the EVSE via the station communication port, receive EVSE attributes from the EVSE, and issue commands to the VMS to manage power flow between the electric vehicle and the EVSE based on the EVSE attributes. An electric vehicle may interface with the grid by establishing communication with the EVSE, receiving the EVSE attributes, and managing power flow between the EVE and the grid based on the EVSE attributes.

  11. Location Estimation for an Autonomously Guided Vehicle using an Augmented Kalman Filter to Autocalibrate the Odometry

    DEFF Research Database (Denmark)

    Larsen, Thomas Dall; Bak, Martin; Andersen, Nils Axel

    1998-01-01

    A Kalman filter using encoder readings as inputs and vision measurements as observations is designed as a location estimator for an autonomously guided vehicle (AGV). To reduce the effect of modelling errors an augmented filter that estimates the true system parameters is designed. The traditional...

  12. Temporal Oculomotor Inhibition of Return and Spatial Facilitation of Return in a Visual Encoding Task

    Directory of Open Access Journals (Sweden)

    Steven G Luke

    2013-07-01

    Full Text Available Oculomotor inhibition of return (O-IOR is an increase in saccade latency prior to an eye movement to a recently fixated location compared to other locations. It has been proposed that this temporal O-IOR may have spatial consequences, facilitating foraging by inhibiting return to previously attended regions. In order to test this possibility, participants viewed arrays of objects and of words while their eye movements were recorded. Temporal O-IOR was observed, with equivalent effects for object and word arrays, indicating that temporal O-IOR is an oculomotor phenomenon independent of array content. There was no evidence for spatial inhibition of return. Instead, spatial facilitation of return was observed: Participants were significantly more likely than chance to make return saccades and to refixate just-visited locations. Further, the likelihood of making a return saccade to an object or word was contingent on the amount of time spent viewing that object or word before leaving it. This suggests that, unlike temporal O-IOR, return probability is influenced by cognitive processing. Taken together, these results are inconsistent with the hypothesis that inhibition of return functions as a foraging facilitator. The results also provide strong evidence for a different oculomotor bias that could serve as a foraging facilitator: saccadic momentum, a tendency to repeat the most recently executed saccade program. We suggest that models of visual attention could incorporate saccadic momentum in place of inhibition of return.

  13. Mars Sample Return Architecture Overview

    Science.gov (United States)

    Edwards, C. D.; Vijendran, S.

    2018-04-01

    NASA and ESA are exploring potential concepts for a Sample Retrieval Lander and Earth Return Orbiter that could return samples planned to be collected and cached by the Mars 2020 rover mission. We provide an overview of the Mars Sample Return architecture.

  14. Applications of a saving method with max-min ant system to a vehicle routing problem with time windows and speed limits

    Directory of Open Access Journals (Sweden)

    Suphan Sodsoon

    2014-06-01

    Full Text Available This study aims to solve a Vehicle Routing Problem with Time Windows and Speed Limits (VRPTWSL, which has received considerable attention in recent years. The vehicle routing problem with time windows is an extension of the well-known Vehicle Routing Problem (VRP and involves a fleet of vehicles set of from a depot to serve a number of customers at different geographic locations with various demands within specific time and speed limits before returning to the depot eventually. To solve the problem, an efficient Saving Method-Max Min Ant System (Saving-MMAS with Local Search algorithm is applied. Using minimization of the total transportation costs as the objective of the extension VRPTWSL, a mathematic model is constructed. Finally, the Saving-MMAS algorithms indicated the good quality of the method in this problem.

  15. 26 CFR 20.6018-2 - Returns; person required to file return.

    Science.gov (United States)

    2010-04-01

    ... executor or administrator shall file the return. If there is more than one executor or administrator, the return must be made jointly by all. If there is no executor or administrator appointed, qualified and... decedent situated in the United States is constituted an executor for purposes of the tax (see § 20.2203-1...

  16. On the Suitability of Interleaved Switched Capacitor Converter as an Interface for Electric Vehicle Dual Energy Storage Systems

    Energy Technology Data Exchange (ETDEWEB)

    Amjadi, Zahra; Williamson, Sheldon

    2010-09-15

    This paper presents the analysis and novel hybrid controller design for an interleaved 2-quadrant switched capacitor (SC) bidirectional DC/DC converter for a hybrid electric vehicle (HEV) dual energy storage system. The designed novel control strategy enables simpler dynamics compared to a standard buck converter with input filter, good regulation capability, low EMI, lower source current ripple, ease of control, and continuous input current waveform in both buck as well as boost modes of operation.

  17. Simulation modeling of wheeled vehicle dynamics on the stand "Roller"

    Directory of Open Access Journals (Sweden)

    G. O. Kotiev

    2014-01-01

    Full Text Available The tests are an integral part of the wheeled vehicle design, manufacturing, and operation. The need for their conducting arises from the research and experimental activities to assess the qualitative and quantitative characteristics of the vehicles in general, as well as the individual components and assemblies. It is obvious that a variety of design features of wheeled vehicles request a development of methods both for experimental studies and for creating the original bench equipment for these purposes.The main positive feature of bench tests of automotive engineering is a broad capability to control the combinations of traction loads, speed rates, and external input conditions. Here, the steady state conditions can be used for a long time, allowing all the necessary measurements to be made, including those with video and photo recording experiment.It is known that the benefits of test "M" type (using a roller dynamometer include a wide range of test modes, which do not depend on the climatic conditions, as well as a capability to use a computer-aided testing programs. At the same time, it is known that the main drawback of bench tests of full-size vehicle is that the tire rolling conditions on the drum mismatch to the real road pavements, which are difficult to simulate on the drum surface. This problem can be solved owing to wheeled vehicle tests at the benches "Roller" to be, in efficiency, the most preferable research method. The article gives a detailed presentation of developed at BMSTU approach to its solving.Problem of simulation mathematical modeling has been solved for the vehicle with the wheel formula 8 × 8, and individual wheel-drive.The simulation results have led to the conclusion that the proposed principle to simulate a vehicle rolling on a smooth non-deformable support base using a bench " Roller " by simulation modeling is efficient.

  18. ColloInputGenerator

    DEFF Research Database (Denmark)

    2013-01-01

    This is a very simple program to help you put together input files for use in Gries' (2007) R-based collostruction analysis program. It basically puts together a text file with a frequency list of lexemes in the construction and inserts a column where you can add the corpus frequencies. It requires...... it as input for basic collexeme collostructional analysis (Stefanowitsch & Gries 2003) in Gries' (2007) program. ColloInputGenerator is, in its current state, based on programming commands introduced in Gries (2009). Projected updates: Generation of complete work-ready frequency lists....

  19. Airframe Integration Trade Studies for a Reusable Launch Vehicle

    Science.gov (United States)

    Dorsey, John T.; Wu, Chauncey; Rivers, Kevin; Martin, Carl; Smith, Russell

    1999-01-01

    Future launch vehicles must be lightweight, fully reusable and easily maintained if low-cost access to space is to be achieved. The goal of achieving an economically viable Single-Stage-to-Orbit (SSTO) Reusable Launch Vehicle (RLV) is not easily achieved and success will depend to a large extent on having an integrated and optimized total system. A series of trade studies were performed to meet three objectives. First, to provide structural weights and parametric weight equations as inputs to configuration-level trade studies. Second, to identify, assess and quantify major weight drivers for the RLV airframe. Third, using information on major weight drivers, and considering the RLV as an integrated thermal structure (composed of thrust structures, tanks, thermal protection system, insulation and control surfaces), identify and assess new and innovative approaches or concepts that have the potential for either reducing airframe weight, improving operability, and/or reducing cost.

  20. Solar Electric Propulsion Technologies Being Designed for Orbit Transfer Vehicle Applications

    Science.gov (United States)

    Sarver-Verhey, Timothy R.; Hoffman, David J.; Kerslake, Thomas W.; Oleson, Steven R.; Falck, Robert D.

    2002-01-01

    There is increasing interest in employing Solar Electric Propulsion (SEP) for new missions requiring transfer from low Earth orbit to the Earth-Moon Lagrange point, L1. Mission architecture plans place the Gateway Habitat at L1 in the 2011 to 2016 timeframe. The Gateway Habitat is envisioned to be used for Lunar exploration, space telescopes, and planetary mission staging. In these scenarios, an SEP stage, or "tug," is used to transport payloads to L1--such as the habitat module, lunar excursion and return vehicles, and chemical propellant for return crew trips. SEP tugs are attractive because they are able to efficiently transport large (less than 10,000 kg) payloads while minimizing propellant requirements. To meet the needs of these missions, a preliminary conceptual design for a general-purpose SEP tug was developed that incorporates several of the advanced space power and in-space propulsion technologies (such as high-power gridded ion and Hall thrusters, high-performance thin-film photovoltaics, lithium-ion batteries, and advanced high-voltage power processing) being developed at the NASA Glenn Research Center. A spreadsheet-based vehicle system model was developed for component sizing and is currently being used for mission planning. This model incorporates a low-thrust orbit transfer algorithm to make preliminary determinations of transfer times and propellant requirements. Results from this combined tug mass estimation and orbit transfer model will be used in a higher fidelity trajectory model to refine the analysis.

  1. PUC fast track nips returns

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    In the first of what it says will be annual cost-of-capital proceedings to set returns on equity and rates of return on rate base for electric utilities, the California Public Utilities Commission (PUC) lowered from 1989 levels the 1990 returns on common equity (ROE) and rates of return (ROR) for the state's four major investor-owned electric utilities. Under this fast-track procedure, by May 8 of every year, utilities will have to file an application for rate adjustments that reflect their projected costs of capital for the following year

  2. The return to foreign aid

    DEFF Research Database (Denmark)

    Dalgaard, Carl-Johan Lars; Hansen, Henrik

    We investigate the marginal productivity of investment across countries. The aim is to estimate the return on investments financed by foreign aid and by domestic resource mobilization, using aggregate data. Both returns are expected to vary across countries and time. Consequently we develop...... a correlated random coefficients model, to estimate the average aggregate return on ‘aid investments’ and ‘domestic investments’. Across different estimators and two different sources for GDP and investment data our findings are remarkably robust; the average gross return on ‘aid investments’ is about 20 per...

  3. Electric vehicle station equipment for grid-integrated vehicles

    Science.gov (United States)

    Kempton, Willett; Kiamilev, Fouad; McGee, Rodney; Waite, Nick

    2017-09-05

    Methods, systems, and apparatus transferring power between the grid and an electric vehicle are disclosed. The apparatus may include at least one vehicle communication port for interfacing with electric vehicle equipment (EVE) and a processor coupled to the at least one vehicle communication port to establish communication with the EVE, receive EVE attributes from the EVE, and transmit electric vehicle station equipment (EVSE) attributes to the EVE. Power may be transferred between the grid and the electric vehicle by maintaining EVSE attributes, establishing communication with the EVE, and transmitting the EVSE maintained attributes to the EVE.

  4. Design of an Autonomous Underwater Vehicle to Calibrate the Europa Clipper Ice-Penetrating Radar

    Science.gov (United States)

    Stone, W.; Siegel, V.; Kimball, P.; Richmond, K.; Flesher, C.; Hogan, B.; Lelievre, S.

    2013-12-01

    Jupiter's moon Europa has been prioritized as the target for the Europa Clipper flyby mission. A key science objective for the mission is to remotely characterize the ice shell and any subsurface water, including their heterogeneity, and the nature of surface-ice-ocean exchange. This objective is a critical component of the mission's overarching goal of assessing the habitability of Europa. The instrument targeted for addressing key aspects of this goal is an ice-penetrating radar (IPR). As a primary goal of our work, we will tightly couple airborne IPR studies of the Ross Ice Shelf by the Europa Clipper radar team with ground-truth data to be obtained from sub-glacial sonar and bio-geochemical mapping of the corresponding ice-water and water-rock interfaces using an advanced autonomous underwater vehicle (AUV). The ARTEMIS vehicle - a heavily morphed long-range, low drag variant of the highly successful 4-degree-of-freedom hovering sub-ice ENDURANCE bot -- will be deployed from a sea-ice drill hole adjacent the McMurdo Ice Shelf (MIS) and will perform three classes of missions. The first includes original exploration and high definition mapping of both the ice-water interface and the benthic interface on a length scale (approximately 10 kilometers under-ice penetration radius) that will definitively tie it to the synchronous airborne IPR over-flights. These exploration and mapping missions will be conducted at up to 10 different locations along the MIS in order to capture varying ice thickness and seawater intrusion into the ice shelf. Following initial mapping characterization, the vehicle will conduct astrobiology-relevant proximity operations using bio-assay sensors (custom-designed UV fluorescence and machine-vision-processed optical imagery) followed by point-targeted studies at regions of interest. Sample returns from the ice-water interface will be triggered autonomously using real-time-processed instrument data and onboard decision-to-collect algorithms

  5. A Pseudo-Parallel Genetic Algorithm Integrating Simulated Annealing for Stochastic Location-Inventory-Routing Problem with Consideration of Returns in E-Commerce

    Directory of Open Access Journals (Sweden)

    Bailing Liu

    2015-01-01

    Full Text Available Facility location, inventory control, and vehicle routes scheduling are three key issues to be settled in the design of logistics system for e-commerce. Due to the online shopping features of e-commerce, customer returns are becoming much more than traditional commerce. This paper studies a three-phase supply chain distribution system consisting of one supplier, a set of retailers, and a single type of product with continuous review (Q, r inventory policy. We formulate a stochastic location-inventory-routing problem (LIRP model with no quality defects returns. To solve the NP-hand problem, a pseudo-parallel genetic algorithm integrating simulated annealing (PPGASA is proposed. The computational results show that PPGASA outperforms GA on optimal solution, computing time, and computing stability.

  6. Modelling energy demand for a fleet of hydrogen-electric vehicles interacting with a clean energy hub

    International Nuclear Information System (INIS)

    Syed, F.; Fowler, M.; Wan, D.; Maniyali, Y.

    2009-01-01

    This paper details the development of an energy demand model for a hydrogen-electric vehicle fleet and the modelling of the fleet interactions with a clean energy hub. The approach taken is to model the architecture and daily operation of every individual vehicle in the fleet. A generic architecture was developed based on understanding gained from existing detailed models used in vehicle powertrain design, with daily operation divided into two periods: charging and travelling. During the charging period, the vehicle charges its Electricity Storage System (ESS) and refills its Hydrogen Storage System (HSS), and during the travelling period, the vehicle depletes the ESS and HSS based on distance travelled. Daily travel distance is generated by a stochastic model and is considered an input to the fleet model. The modelling of a clean energy hub is also presented. The clean energy hub functions as an interface between electricity supply and the energy demand (i.e. hydrogen and electricity) of the vehicle fleet. Finally, a sample case is presented to demonstrate the use of the fleet model and its implications on clean energy hub sizing. (author)

  7. Fundamental volatility and stock returns : does fundamental volatility explain stock returns?

    OpenAIRE

    Selboe, Guner K.; Virdee, Jaspal Singh

    2017-01-01

    In this thesis, we investigate whether the fundamental uncertainty can explain the crosssection of stock returns. To measure the fundamental uncertainty, we estimate rolling standard deviations and accounting betas of four different fundamentals: revenues, gross profit, earnings and cash flows. The standard deviation and the beta of revenues significantly explain returns in the Fama-Macbeth procedure, but only appears significant among smaller stocks in the portfolio formation ...

  8. Advanced Curation: Solving Current and Future Sample Return Problems

    Science.gov (United States)

    Fries, M.; Calaway, M.; Evans, C.; McCubbin, F.

    2015-01-01

    Advanced Curation is a wide-ranging and comprehensive research and development effort at NASA Johnson Space Center that identifies and remediates sample related issues. For current collections, Advanced Curation investigates new cleaning, verification, and analytical techniques to assess their suitability for improving curation processes. Specific needs are also assessed for future sample return missions. For each need, a written plan is drawn up to achieve the requirement. The plan draws while upon current Curation practices, input from Curators, the analytical expertise of the Astromaterials Research and Exploration Science (ARES) team, and suitable standards maintained by ISO, IEST, NIST and other institutions. Additionally, new technologies are adopted on the bases of need and availability. Implementation plans are tested using customized trial programs with statistically robust courses of measurement, and are iterated if necessary until an implementable protocol is established. Upcoming and potential NASA missions such as OSIRIS-REx, the Asteroid Retrieval Mission (ARM), sample return missions in the New Frontiers program, and Mars sample return (MSR) all feature new difficulties and specialized sample handling requirements. The Mars 2020 mission in particular poses a suite of challenges since the mission will cache martian samples for possible return to Earth. In anticipation of future MSR, the following problems are among those under investigation: What is the most efficient means to achieve the less than 1.0 ng/sq cm total organic carbon (TOC) cleanliness required for all sample handling hardware? How do we maintain and verify cleanliness at this level? The Mars 2020 Organic Contamination Panel (OCP) predicts that organic carbon, if present, will be present at the "one to tens" of ppb level in martian near-surface samples. The same samples will likely contain wt% perchlorate salts, or approximately 1,000,000x as much perchlorate oxidizer as organic carbon

  9. Multi-Objective Sliding Mode Control on Vehicle Cornering Stability with Variable Gear Ratio Actuator-Based Active Front Steering Systems

    Science.gov (United States)

    Ma, Xinbo; Wong, Pak Kin; Zhao, Jing; Xie, Zhengchao

    2016-01-01

    Active front steering (AFS) is an emerging technology to improve the vehicle cornering stability by introducing an additional small steering angle to the driver’s input. This paper proposes an AFS system with a variable gear ratio steering (VGRS) actuator which is controlled by using the sliding mode control (SMC) strategy to improve the cornering stability of vehicles. In the design of an AFS system, different sensors are considered to measure the vehicle state, and the mechanism of the AFS system is also modelled in detail. Moreover, in order to improve the cornering stability of vehicles, two dependent objectives, namely sideslip angle and yaw rate, are considered together in the design of SMC strategy. By evaluating the cornering performance, Sine with Dwell and accident avoidance tests are conducted, and the simulation results indicate that the proposed SMC strategy is capable of improving the cornering stability of vehicles in practice. PMID:28036037

  10. Some Problems of Rocket-Space Vehicles' Characteristics co- ordination

    Science.gov (United States)

    Sergienko, Alexander A.

    2002-01-01

    of the XX century suffered a reverse. The designers of the United States' firms and enterprises of aviation and rocket-space industry (Boeing, Rocketdyne, Lockheed Martin, McDonnell Douglas, Rockwell, etc.) and NASA (Marshall Space Flight Center, Johnson Space Center, Langley Research Center and Lewis Research Center and others) could not correctly co-ordinate the characteristics of a propulsion system and a space vehicle for elaboration of the "Single-Stage-To-Orbit" reusable vehicle (SSTO) as an integral whole system, which is would able to inject a payload into an orbit and to return back on the Earth. jet nozzle design as well as the choice of propulsion system characteristics, ensuring the high ballistic efficiency, are considered in the present report. The efficiency criterions for the engine and launch system parameters optimization are discussed. The new methods of the nozzle block optimal parameters' choice for the satisfaction of the object task of flight are suggested. The family of SSTO with a payload mass from 5 to 20 ton and initial weight under 800 ton is considered.

  11. The influence of tyre transient side force properties on vehicle lateral acceleration for a time-varying vertical force

    Science.gov (United States)

    Takahashi, Toshimichi

    2018-05-01

    The tyre model which formerly developed by the author et al. and describes the tyre transient responses of side force and aligning moment under the time-varying vertical force was implemented to the vehicle dynamics simulation software and the influence of tyre side force transient property on the vehicle behaviour was investigated. The vehicle responses with/without tyre transient property on sinusoidally undulated road surfaces were simulated and compared. It was found that the average lateral acceleration of the vehicle at the sinusoidal steering wheel angle input decreases on the undulated road of long wavelength (3 m) for both cases, but when the wavelength becomes shorter (1 m), the average lateral acceleration increases only in the case that the transient property is considered. The cause of those changes is explained by using the tyre-related variables. Also the steady-state turning behaviour of the vehicle on undulated roads are shown and discussed.

  12. GHG emissions from sugar cane ethanol, plug-in hybrids, heavy duty gasoline vehicles and hybrids, and materials review

    International Nuclear Information System (INIS)

    2006-01-01

    This report provided updates of new work and new pathways added to the GHGenius model. The model was developed to analyze lifecycle emissions of contaminants associated with the production and use of alternative and traditional fuels, and is continually updated with new information on existing processes and new innovations. The report described the addition of a new table that showed fossil energy consumption per km driven. New information on energy requirements to remove sulphur from gasoline and diesel fuel in Canada were provided. The report also outlined a new pathway for plug-in hybrid battery-powered electric and gasoline vehicles. Vehicle weight was included as part of the user inputs for modelling gasoline powered heavy duty vehicles and gasoline hybrid heavy duty vehicles. Information on the production processes of ethanol from sugar cane were also added to the model. Amounts of energy consumed during the manufacture of materials for vehicles were also incorporated into the model. 34 refs., 39 tabs., 6 figs

  13. Classifying Returns as Extreme

    DEFF Research Database (Denmark)

    Christiansen, Charlotte

    2014-01-01

    I consider extreme returns for the stock and bond markets of 14 EU countries using two classification schemes: One, the univariate classification scheme from the previous literature that classifies extreme returns for each market separately, and two, a novel multivariate classification scheme tha...

  14. Robust adaptive control for Unmanned Aerial Vehicles

    Science.gov (United States)

    Kahveci, Nazli E.

    The objective of meeting higher endurance requirements remains a challenging task for any type and size of Unmanned Aerial Vehicles (UAVs). According to recent research studies significant energy savings can be realized through utilization of thermal currents. The navigation strategies followed across thermal regions, however, are based on rather intuitive assessments of remote pilots and lack any systematic path planning approaches. Various methods to enhance the autonomy of UAVs in soaring applications are investigated while seeking guarantees for flight performance improvements. The dynamics of the aircraft, small UAVs in particular, are affected by the environmental conditions, whereas unmodeled dynamics possibly become significant during aggressive flight maneuvers. Besides, the demanded control inputs might have a magnitude range beyond the limits dictated by the control surface actuators. The consequences of ignoring these issues can be catastrophic. Supporting this claim NASA Dryden Flight Research Center reports considerable performance degradation and even loss of stability in autonomous soaring flight tests with the subsequent risk of an aircraft crash. The existing control schemes are concluded to suffer from limited performance. Considering the aircraft dynamics and the thermal characteristics we define a vehicle-specific trajectory optimization problem to achieve increased cross-country speed and extended range of flight. In an environment with geographically dispersed set of thermals of possibly limited lifespan, we identify the similarities to the Vehicle Routing Problem (VRP) and provide both exact and approximate guidance algorithms for the navigation of automated UAVs. An additional stochastic approach is used to quantify the performance losses due to incorrect thermal data while dealing with random gust disturbances and onboard sensor measurement inaccuracies. One of the main contributions of this research is a novel adaptive control design with

  15. Total dose induced increase in input offset voltage in JFET input operational amplifiers

    International Nuclear Information System (INIS)

    Pease, R.L.; Krieg, J.; Gehlhausen, M.; Black, J.

    1999-01-01

    Four different types of commercial JFET input operational amplifiers were irradiated with ionizing radiation under a variety of test conditions. All experienced significant increases in input offset voltage (Vos). Microprobe measurement of the electrical characteristics of the de-coupled input JFETs demonstrates that the increase in Vos is a result of the mismatch of the degraded JFETs. (authors)

  16. Disturbance observer-based L1 robust tracking control for hypersonic vehicles with T-S disturbance modeling

    Directory of Open Access Journals (Sweden)

    Yang Yi

    2016-11-01

    Full Text Available This article concerns a disturbance observer-based L1 robust anti-disturbance tracking algorithm for the longitudinal models of hypersonic flight vehicles with different kinds of unknown disturbances. On one hand, by applying T-S fuzzy models to represent those modeled disturbances, a disturbance observer relying on T-S disturbance models can be constructed to track the dynamics of exogenous disturbances. On the other hand, L1 index is introduced to analyze the attenuation performance of disturbance for those unmodeled disturbances. By utilizing the existing convex optimization algorithm, a disturbance observer-based proportional-integral-controlled input is proposed such that the stability of hypersonic flight vehicles can be ensured and the tracking error for velocity and altitude in hypersonic flight vehicle models can converge to equilibrium point. Furthermore, the satisfactory disturbance rejection and attenuation with L1 index can be obtained simultaneously. Simulation results on hypersonic flight vehicle models can reflect the feasibility and effectiveness of the proposed control algorithm.

  17. Potential Occupant Injury Reduction in Pre-Crash System Equipped Vehicles in the Striking Vehicle of Rear-end Crashes.

    Science.gov (United States)

    Kusano, Kristofer D; Gabler, Hampton C

    2010-01-01

    To mitigate the severity of rear-end and other collisions, Pre-Crash Systems (PCS) are being developed. These active safety systems utilize radar and/or video cameras to determine when a frontal crash, such as a front-to-back rear-end collisions, is imminent and can brake autonomously, even with no driver input. Of these PCS features, the effects of autonomous pre-crash braking are estimated. To estimate the maximum potential for injury reduction due to autonomous pre-crash braking in the striking vehicle of rear-end crashes, a methodology is presented for determining 1) the reduction in vehicle crash change in velocity (ΔV) due to PCS braking and 2) the number of injuries that could be prevented due to the reduction in collision severity. Injury reduction was only performed for belted drivers, as unbelted drivers have an unknown risk of being thrown out of position. The study was based on 1,406 rear-end striking vehicles from NASS / CDS years 1993 to 2008. PCS parameters were selected from realistic values and varied to examine the effect on system performance. PCS braking authority was varied from 0.5 G's to 0.8 G's while time to collision (TTC) was held at 0.45 seconds. TTC was then varied from 0.3 second to 0.6 seconds while braking authority was held constant at 0.6 G's. A constant braking pulse (step function) and ramp-up braking pulse were used. The study found that automated PCS braking could reduce the crash ΔV in rear-end striking vehicles by an average of 12% - 50% and avoid 0% - 14% of collisions, depending on PCS parameters. Autonomous PCS braking could potentially reduce the number of injured drivers who are belted by 19% to 57%.

  18. Close Look at Hybrid Vehicle Loyalty and Ownership

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ho-Ling [ORNL; Chin, Shih-Miao [ORNL; Wilson, Daniel W [ORNL; Oliveira Neto, Francisco Moraes [ORNL; Taylor, Rob D [ORNL

    2013-01-01

    In a news release dated April 9, 2012, Polk stated that only 35% of hybrid owners bought a hybrid again when they returned to market in 2011. These findings were based on an internal study conducted by Polk. The study also indicated that if repurchase behavior among the high volume audience of Toyota Prius owners wasn t factored in; hybrid loyalty would drop to under 25%. This news release has generated a lot of interest and concern by the automobile industry as well as consumers, since it was published, and caused many to think about the idea of hybrid loyalty as well as factors that influence consumers. Most reactions to the 35% hybrid loyalty dealt with concerns of the viability of hybrid technology as part of the solution to address transportation energy challenges. This paper attempts to shed more light on Polk s hybrid loyalty study as well as explore several information sources concerning hybrid loyalty status. Specifically, major factors that might impact the selection and acquisition of hybrid vehicles are addressed. This includes investigating the associations between hybrid market shares and influencing factors like fuel price and hybrid incentives, as well as the availability of hybrid models and other highly fuel efficient vehicle options. This effort is not in-depth study, but rather a short study to see if Polk s claim could be validated. This study reveals that Polk s claim was rather misleading because its definition of loyalty was very narrow. This paper also suggests that Polk s analysis failed to account for some very important factors, raising the question of whether it is fair to compare a vehicle drive train option (which hybrids are) with a vehicle brand in terms of loyalty and also raises the question of whether hybrid loyalty is even a valid point to consider. This report maintains that Polk s study does not prove that hybrid owners were dissatisfied with their vehicles, which was a common theme among reporting news agencies when Polk

  19. Drivability Improvement Control for Vehicle Start-Up Applied to an Automated Manual Transmission

    Directory of Open Access Journals (Sweden)

    Danna Jiang

    2017-01-01

    Full Text Available Drivability is the key factor for the automated manual transmission. It includes fast response to the driver’s demand and the driving comfort. This paper deals with a control methodology applied to an automated manual transmission vehicle for drivability enhancement during vehicle start-up phase. Based on a piecewise model of powertrain, a multiple-model predictive controller (mMPC is designed with the engine speed, clutch disc speed, and wheel speed as the measurable input variables and the engine torque reference and clutch friction torque reference as the controller’s output variables. The model not only includes the clutch dynamic, the flexible shaft dynamic, but also includes the actuators’ delay character. Considering the driver’s intention, a slipping speed trajectory is generated based on the acceleration pedal dynamically. The designed control strategy is verified on a complete powertrain and longitudinal vehicle dynamic model with different driver’s torque demands.

  20. Transportation Energy Futures Series: Vehicle Technology Deployment Pathways: An Examination of Timing and Investment Constraints

    Energy Technology Data Exchange (ETDEWEB)

    Plotkin, S.; Stephens, T.; McManus, W.

    2013-03-01

    Scenarios of new vehicle technology deployment serve various purposes; some will seek to establish plausibility. This report proposes two reality checks for scenarios: (1) implications of manufacturing constraints on timing of vehicle deployment and (2) investment decisions required to bring new vehicle technologies to market. An estimated timeline of 12 to more than 22 years from initial market introduction to saturation is supported by historical examples and based on the product development process. Researchers also consider the series of investment decisions to develop and build the vehicles and their associated fueling infrastructure. A proposed decision tree analysis structure could be used to systematically examine investors' decisions and the potential outcomes, including consideration of cash flow and return on investment. This method requires data or assumptions about capital cost, variable cost, revenue, timing, and probability of success/failure, and would result in a detailed consideration of the value proposition of large investments and long lead times. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency effort to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  1. Transportation Energy Futures Series. Vehicle Technology Deployment Pathways. An Examination of Timing and Investment Constraints

    Energy Technology Data Exchange (ETDEWEB)

    Plotkin, Steve [Argonne National Lab. (ANL), Argonne, IL (United States); Stephens, Thomas [Argonne National Lab. (ANL), Argonne, IL (United States); McManus, Walter [Oakland Univ., Rochester, MI (United States)

    2013-03-01

    Scenarios of new vehicle technology deployment serve various purposes; some will seek to establish plausibility. This report proposes two reality checks for scenarios: (1) implications of manufacturing constraints on timing of vehicle deployment and (2) investment decisions required to bring new vehicle technologies to market. An estimated timeline of 12 to more than 22 years from initial market introduction to saturation is supported by historical examples and based on the product development process. Researchers also consider the series of investment decisions to develop and build the vehicles and their associated fueling infrastructure. A proposed decision tree analysis structure could be used to systematically examine investors' decisions and the potential outcomes, including consideration of cash flow and return on investment. This method requires data or assumptions about capital cost, variable cost, revenue, timing, and probability of success/failure, and would result in a detailed consideration of the value proposition of large investments and long lead times. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency effort to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  2. QR-GARCH-M Model for Risk-Return Tradeoff in U.S. Stock Returns and Business Cycles

    OpenAIRE

    Nyberg, Henri

    2010-01-01

    In the empirical finance literature findings on the risk return tradeoff in excess stock market returns are ambiguous. In this study, we develop a new QR-GARCH-M model combining a probit model for a binary business cycle indicator and a regime switching GARCH-in-mean model for excess stock market return with the business cycle indicator defining the regime. Estimation results show that there is statistically significant variation in the U.S. excess stock returns over the business cycle. Howev...

  3. Electric-Drive Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Septon, Kendall K [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-11

    Electric-drive vehicles use electricity as their primary fuel or to improve the efficiency of conventional vehicle designs. These vehicles can be divided into three categories: Hybrid electric vehicles (HEVs), Plug-in hybrid electric vehicles (PHEVs), All-electric vehicles (EVs). Together, PHEVs and EVs can also be referred to as plug-in electric vehicles (PEVs).

  4. Electric-Drive Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-09-01

    Electric-drive vehicles use electricity as their primary fuel or to improve the efficiency of conventional vehicle designs. These vehicles can be divided into three categories: Hybrid electric vehicles (HEVs), Plug-in hybrid electric vehicles (PHEVs), All-electric vehicles (EVs). Together, PHEVs and EVs can also be referred to as plug-in electric vehicles (PEVs).

  5. Environmental Evaluation of New Generation Vehicles and Vehicle Components

    Energy Technology Data Exchange (ETDEWEB)

    Schexnayder, S.M.

    2002-02-06

    This report documents assessments that address waste issues and life cycle impacts associated with the vehicle materials and vehicle technologies being developed under the Partnership for a New Generation of Vehicles (PNGV) program. We refer to these vehicles as 3XVs, referring to the PNGV goal that their fuel mileage be three times better than the baseline vehicle. To meet the program's fuel consumption goals, these vehicles substitute lightweight materials for heavier materials such as steel and iron that currently dominate the composition of vehicles, and use engineering and power system changes. Alternative power systems being developed through the PNGV program include batteries for hybrid electric vehicles and fuel cells. With respect to all these developments, it is imperative to learn what effects they will have on the environment before adopting these designs and technologies on a large-scale basis.

  6. Return Migration as Failure or Success?: The Determinants of Return Migration Intentions Among Moroccan Migrants in Europe.

    Science.gov (United States)

    de Haas, Hein; Fokkema, Tineke; Fihri, Mohamed Fassi

    Different migration theories generate competing hypotheses with regard to determinants of return migration. While neoclassical migration theory associates migration to the failure to integrate at the destination, the new economics of labour migration sees return migration as the logical stage after migrants have earned sufficient assets and knowledge and to invest in their origin countries. The projected return is then likely to be postponed for sustained or indefinite periods if integration is unsuccessful. So, from an indication or result of integration failure return is rather seen as a measure of success. Drawing on recent survey data ( N  = 2,832), this article tests these hypotheses by examining the main determinants of return intention among Moroccan migrants across Europe. The results indicate that structural integration through labour market participation, education and the maintenance of economic and social ties with receiving countries do not significantly affect return intentions. At the same time, investments and social ties to Morocco are positively related, and socio-cultural integration in receiving countries is negatively related to return migration intentions. The mixed results corroborate the idea that there is no uniform process of (return) migration and that competing theories might therefore be partly complementary.

  7. Robust stabilization control based on guardian maps theory for a longitudinal model of hypersonic vehicle.

    Science.gov (United States)

    Liu, Yanbin; Liu, Mengying; Sun, Peihua

    2014-01-01

    A typical model of hypersonic vehicle has the complicated dynamics such as the unstable states, the nonminimum phases, and the strong coupling input-output relations. As a result, designing a robust stabilization controller is essential to implement the anticipated tasks. This paper presents a robust stabilization controller based on the guardian maps theory for hypersonic vehicle. First, the guardian maps theories are provided to explain the constraint relations between the open subsets of complex plane and the eigenvalues of the state matrix of closed-loop control system. Then, a general control structure in relation to the guardian maps theories is proposed to achieve the respected design demands. Furthermore, the robust stabilization control law depending on the given general control structure is designed for the longitudinal model of hypersonic vehicle. Finally, a simulation example is provided to verify the effectiveness of the proposed methods.

  8. 75 FR 76940 - Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic...

    Science.gov (United States)

    2010-12-10

    ... DEPARTMENT OF THE TREASURY Internal Revenue Service 26 CFR Parts 1 and 301 [REG-100194-10] RIN 1545-BJ52 Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic... for ``specified tax return prepares,''. FOR FURTHER INFORMATION CONTACT: Keith L. Brau at (202) 622...

  9. A Perishable Inventory Model with Return

    Science.gov (United States)

    Setiawan, S. W.; Lesmono, D.; Limansyah, T.

    2018-04-01

    In this paper, we develop a mathematical model for a perishable inventory with return by assuming deterministic demand and inventory dependent demand. By inventory dependent demand, it means that demand at certain time depends on the available inventory at that time with certain rate. In dealing with perishable items, we should consider deteriorating rate factor that corresponds to the decreasing quality of goods. There are also costs involved in this model such as purchasing, ordering, holding, shortage (backordering) and returning costs. These costs compose the total costs in the model that we want to minimize. In the model we seek for the optimal return time and order quantity. We assume that after some period of time, called return time, perishable items can be returned to the supplier at some returning costs. The supplier will then replace them in the next delivery. Some numerical experiments are given to illustrate our model and sensitivity analysis is performed as well. We found that as the deteriorating rate increases, returning time becomes shorter, the optimal order quantity and total cost increases. When considering the inventory-dependent demand factor, we found that as this factor increases, assuming a certain deteriorating rate, returning time becomes shorter, optimal order quantity becomes larger and the total cost increases.

  10. A Collaborative Analysis Tool for Integrated Hypersonic Aerodynamics, Thermal Protection Systems, and RBCC Engine Performance for Single Stage to Orbit Vehicles

    Science.gov (United States)

    Stanley, Thomas Troy; Alexander, Reginald; Landrum, Brian

    2000-01-01

    the process may be repeated altering the trajectory or some other input to reduce the TPS mass. E-PSURBCC is an "engine performance" model and requires the specification of inlet air static temperature and pressure as well as Mach number (which it pulls from the HYFIM and POST trajectory files), and calculates the corresponding stagnation properties. The engine air flow path geometry includes inlet, a constant area section where the rocket is positioned, a subsonic diffuser, a constant area afterburner, and either a converging nozzle or a converging-diverging nozzle. The current capabilities of E-PSURBCC ejector and ramjet mode treatment indicated that various complex flow phenomena including multiple choking and internal shocks can occur for combinations of geometry/flow conditions. For a given input deck defining geometry/flow conditions, the program first goes through a series of checks to establish whether the input parameters are sound in terms of a solution path. If the vehicle/engine performance fails mission goals, the engineer is able to collaboratively alter the vehicle moldline to change aerodynamics, or trajectory, or some other input to achieve orbit. The problem described is an example of the need for collaborative design and analysis. RECIPE is a cross-platform application capable of hosting a number of engineers and designers across the Internet for distributed and collaborative engineering environments. Such integrated system design environments allow for collaborative team design analysis for performing individual or reduced team studies. To facilitate the larger number of potential runs that may need to be made, RECIPE connects the computer codes that calculate the trajectory data, aerodynamic data based on vehicle geometry, heat rate data, TPS masses, and vehicle and engine performance, so that the output from each tool is easily transferred to the model input files that need it.

  11. Energy Returned On Investment of Engineered Geothermal Systems Annual Report FY2011

    Energy Technology Data Exchange (ETDEWEB)

    Mansure, A.J.

    2011-12-31

    Energy Return On Investment (EROI) is an important figure of merit for assessing the viability of energy alternatives. For geothermal electric power generation, EROI is determined by the electricity delivered to the consumer compared to the energy consumed to construct, operate, and decommission the facility. Critical factors in determining the EROI of Engineered Geothermal Systems (EGS) are examined in this work. These include the input energy embodied into the system. The embodied energy includes the energy contained in the materials, as well as, that consumed in each stage of manufacturing from mining the raw materials to assembling the finished plant. Also critical are the system boundaries and value of the energy - heat is not as valuable as electrical energy.

  12. Description of light-vehicle pre-crash scenarios for safety applications based on vehicle-to-vehicle communications

    Science.gov (United States)

    2013-05-31

    This report describes pre-crash scenarios that might be addressed by vehicle-to-vehicle communications. The focus is on crashes involving at least 1 light vehicle with a gross vehicle weight rating of 10,000 pounds or less. The 2004-2008 General Esti...

  13. Electric vehicles

    Science.gov (United States)

    1990-03-01

    Quiet, clean, and efficient, electric vehicles (EVs) may someday become a practical mode of transportation for the general public. Electric vehicles can provide many advantages for the nation's environment and energy supply because they run on electricity, which can be produced from many sources of energy such as coal, natural gas, uranium, and hydropower. These vehicles offer fuel versatility to the transportation sector, which depends almost solely on oil for its energy needs. Electric vehicles are any mode of transportation operated by a motor that receives electricity from a battery or fuel cell. EVs come in all shapes and sizes and may be used for different tasks. Some EVs are small and simple, such as golf carts and electric wheel chairs. Others are larger and more complex, such as automobile and vans. Some EVs, such as fork lifts, are used in industries. In this fact sheet, we will discuss mostly automobiles and vans. There are also variations on electric vehicles, such as hybrid vehicles and solar-powered vehicles. Hybrid vehicles use electricity as their primary source of energy, however, they also use a backup source of energy, such as gasoline, methanol or ethanol. Solar-powered vehicles are electric vehicles that use photovoltaic cells (cells that convert solar energy to electricity) rather than utility-supplied electricity to recharge the batteries. These concepts are discussed.

  14. Electric Vehicle Fast-Charging Station Unified Modeling and Stability Analysis in the dq Frame

    Directory of Open Access Journals (Sweden)

    Xiang Wang

    2018-05-01

    Full Text Available The electric vehicle fast-charging station is an important guarantee for the popularity of electric vehicle. As the fast-charging piles are voltage source converters, stability issues will occur in the grid-connected fast-charging station. Since the dynamic input admittance of the fast-charging pile and the dynamic output impedance play an important role in the interaction system stability, the station and grid interaction system is regarded as load-side and source-side sub-systems to build the dynamic impedance model. The dynamic input admittance in matrix form is derived from the fast-charging pile current control loop considering the influence of the LC filter. Similarly, the dynamic output impedance can be obtained similarly by considering the regional power grid capacity, transformer capacity, and feed line length. On this basis, a modified forbidden region-based stability criterion is used for the fast-charging station stability analysis. The frequency-domain case studies and time-domain simulations are presented next to show the influence of factors from both the power grid side and fast-charging pile side. The simulation results validated the effectiveness of the dq frame impedance model and the stability analysis method.

  15. Foreign currency returns and systematic risks

    NARCIS (Netherlands)

    Galsband, V.; Nitschka, T.

    2015-01-01

    We apply an empirical approximation of the intertemporal capital asset pricing model (ICAPM) to show that cross-sectional dispersion in currency returns can be rationalized by differences in currency excess returns' sensitivities to the market return's cash-flow news component. This finding echoes

  16. Observer-based linear parameter varying H∞ tracking control for hypersonic vehicles

    Directory of Open Access Journals (Sweden)

    Yiqing Huang

    2016-11-01

    Full Text Available This article aims to develop observer-based linear parameter varying output feedback H∞ tracking controller for hypersonic vehicles. Due to the complexity of an original nonlinear model of the hypersonic vehicle dynamics, a slow–fast loop linear parameter varying polytopic model is introduced for system stability analysis and controller design. Then, a state observer is developed by linear parameter varying technique in order to estimate the unmeasured attitude angular for slow loop system. Also, based on the designed linear parameter varying state observer, a kind of attitude tracking controller is presented to reduce tracking errors for all bounded reference attitude angular inputs. The closed-loop linear parameter varying system is proved to be quadratically stable by Lypapunov function technique. Finally, simulation results show that the developed linear parameter varying H∞ controller has good tracking capability for reference commands.

  17. Mars Rover Sample Return aerocapture configuration design and packaging constraints

    Science.gov (United States)

    Lawson, Shelby J.

    1989-01-01

    This paper discusses the aerodynamics requirements, volume and mass constraints that lead to a biconic aeroshell vehicle design that protects the Mars Rover Sample Return (MRSR) mission elements from launch to Mars landing. The aerodynamic requirements for Mars aerocapture and entry and packaging constraints for the MRSR elements result in a symmetric biconic aeroshell that develops a L/D of 1.0 at 27.0 deg angle of attack. A significant problem in the study is obtaining a cg that provides adequate aerodynamic stability and performance within the mission imposed constraints. Packaging methods that relieve the cg problems include forward placement of aeroshell propellant tanks and incorporating aeroshell structure as lander structure. The MRSR missions developed during the pre-phase A study are discussed with dimensional and mass data included. Further study is needed for some missions to minimize MRSR element volume so that launch mass constraints can be met.

  18. Hybrid-mode interleaved boost converter design for fuel cell electric vehicles

    International Nuclear Information System (INIS)

    Wen, Huiqing; Su, Bin

    2016-01-01

    Highlights: • A high power interleaved boost converter is designed for a 150 kW high-power fuel cell electric vehicle application. • A hybrid-mode scheme is used: Mode I and mode II are used with each boost converter operating in continuous conduction mode and discontinuous conduction mode. • Boundary conditions for different modes are determined with respect to switching duty ratio and load conditions. • With the proposed scheme, the power density is improved by 44.2% and 34.3% in terms of the converter volume and weight. - Abstract: For Fuel Cell Electric Vehicles, DC-DC power converters are essential to provide energy storage buffers between fuel cell stacks and the traction system because fuel cells show characteristics of low-voltage high-current output and wide output voltage variation. This paper presents a hybrid-mode two-phase interleaved boost converter for fuel cell electric vehicle application in order to improve the power density, minimize the input current ripple, and enhance the system efficiency. Two operation modes are adopted in the practical design: mode I and mode II are used with each boost converter operating in continuous conduction mode and discontinuous conduction mode. The operation, design and control of the interleaved boost converter for different operating modes are discussed with their equivalent circuits. The boundary conditions are distinguished with respect to switching duty ratio and load conditions. Transitions between continuous conduction mode and discontinuous conduction mode are illustrated for the whole duty ratio range. The expressions for inductor current ripple, input current ripple and output voltage ripple are derived and verified by simulation and experimental tests. The efficiency and power density improvements are illustrated to verify the effectiveness of the proposed design scheme.

  19. Nonlinear Constrained Adaptive Backstepping Tracking Control for a Hypersonic Vehicle with Uncertainty

    Directory of Open Access Journals (Sweden)

    Qin Zou

    2015-01-01

    Full Text Available The control problem of a flexible hypersonic vehicle is presented, where input saturation and aerodynamic uncertainty are considered. A control-oriented model including aerodynamic uncertainty is derived for simple controller design due to the nonlinearity and complexity of hypersonic vehicle model. Then it is separated into velocity subsystem and altitude subsystem. On the basis of the integration of robust adaptive control and backstepping technique, respective controller is designed for each subsystem, where an auxiliary signal provided by an additional dynamic system is used to compensate for the control saturation effect. Then to deal with the “explosion of terms” problem inherent in backstepping control, a novel first-order filter is proposed. Simulation results are included to demonstrate the effectiveness of the adaptive backstepping control scheme.

  20. Self-learning control system for plug-in hybrid vehicles

    Science.gov (United States)

    DeVault, Robert C [Knoxville, TN

    2010-12-14

    A system is provided to instruct a plug-in hybrid electric vehicle how optimally to use electric propulsion from a rechargeable energy storage device to reach an electric recharging station, while maintaining as high a state of charge (SOC) as desired along the route prior to arriving at the recharging station at a minimum SOC. The system can include the step of calculating a straight-line distance and/or actual distance between an orientation point and the determined instant present location to determine when to initiate optimally a charge depleting phase. The system can limit extended driving on a deeply discharged rechargeable energy storage device and reduce the number of deep discharge cycles for the rechargeable energy storage device, thereby improving the effective lifetime of the rechargeable energy storage device. This "Just-in-Time strategy can be initiated automatically without operator input to accommodate the unsophisticated operator and without needing a navigation system/GPS input.

  1. Application of a distributed systems architecture for increased speed in image processing on an autonomous ground vehicle

    Science.gov (United States)

    Wright, Adam A.; Momin, Orko; Shin, Young Ho; Shakya, Rahul; Nepal, Kumud; Ahlgren, David J.

    2010-01-01

    This paper presents the application of a distributed systems architecture to an autonomous ground vehicle, Q, that participates in both the autonomous and navigation challenges of the Intelligent Ground Vehicle Competition. In the autonomous challenge the vehicle is required to follow a course, while avoiding obstacles and staying within the course boundaries, which are marked by white lines. For the navigation challenge, the vehicle is required to reach a set of target destinations, known as way points, with given GPS coordinates and avoid obstacles that it encounters in the process. Previously the vehicle utilized a single laptop to execute all processing activities including image processing, sensor interfacing and data processing, path planning and navigation algorithms and motor control. National Instruments' (NI) LabVIEW served as the programming language for software implementation. As an upgrade to last year's design, a NI compact Reconfigurable Input/Output system (cRIO) was incorporated to the system architecture. The cRIO is NI's solution for rapid prototyping that is equipped with a real time processor, an FPGA and modular input/output. Under the current system, the real time processor handles the path planning and navigation algorithms, the FPGA gathers and processes sensor data. This setup leaves the laptop to focus on running the image processing algorithm. Image processing as previously presented by Nepal et. al. is a multi-step line extraction algorithm and constitutes the largest processor load. This distributed approach results in a faster image processing algorithm which was previously Q's bottleneck. Additionally, the path planning and navigation algorithms are executed more reliably on the real time processor due to the deterministic nature of operation. The implementation of this architecture required exploration of various inter-system communication techniques. Data transfer between the laptop and the real time processor using UDP packets

  2. Analysis of different inputs share and determination of energy Indices in broilers production in Mashhad city

    Directory of Open Access Journals (Sweden)

    H Sadrnia

    2017-05-01

    Full Text Available Introduction The high energy consumption is one of the serious problems in poultry industry. The poultry industry consume about five percent of total energy sources in different countries, with consideration of losses, it increases up to 16-20%. In the year 2003 also, the Iranian chicken meat consumption per capita was 13.3 kg, while in the year 2013 it increased to 25.9 kg (FAO, 2014. It shows that in the diet of Iranian people, the chicken meat has become a strategic food. Poultry industry is one of the biggest and most developed industries in Iran. In the past two decays, mainly due to population growth and increase demand of white meats, it is necessary to change and improve energy efficiency in this industry. Technical efficiency of broiler farms in the central region of Saudi Arabia was analyzed through stochastic frontier approach (Alrwis and Francis, 2003. They reported that many farms under study work lower than their total capacity. In the research, the output was chicken meat weight in the term of the kilogram per one period and the inputs were the number of chicks, feed, the total of all variable expenses and fixed input except chicks and feed and the total cost of fixed inputs including building, equipment and machinery used for the broiler houses. They found that the small and large size broiler farms in the Central Region of Saudi Arabia were produced chicken with mean technical efficiency 83 and 88%, respectively (Alrwis and Francis, 2003. Efficiency measurement of broiler production units in Hamadan province was investigated by Fotros and Solgi (2003. They reported that the minimum, maximum and mean technical efficiency under variable return to scale were 12.7, 100 and 64.4%, respectively. Their results showed that technical efficiency at 16.5 (14 units and 42.35% (24 units of farms were more than 90 and 70%, respectively (Fotros and Salgi, 2003. Khorasan Razavi province after Esfahan and Mazandaran provinces is the third

  3. Vehicle speed detection based on gaussian mixture model using sequential of images

    Science.gov (United States)

    Setiyono, Budi; Ratna Sulistyaningrum, Dwi; Soetrisno; Fajriyah, Farah; Wahyu Wicaksono, Danang

    2017-09-01

    Intelligent Transportation System is one of the important components in the development of smart cities. Detection of vehicle speed on the highway is supporting the management of traffic engineering. The purpose of this study is to detect the speed of the moving vehicles using digital image processing. Our approach is as follows: The inputs are a sequence of frames, frame rate (fps) and ROI. The steps are following: First we separate foreground and background using Gaussian Mixture Model (GMM) in each frames. Then in each frame, we calculate the location of object and its centroid. Next we determine the speed by computing the movement of centroid in sequence of frames. In the calculation of speed, we only consider frames when the centroid is inside the predefined region of interest (ROI). Finally we transform the pixel displacement into a time unit of km/hour. Validation of the system is done by comparing the speed calculated manually and obtained by the system. The results of software testing can detect the speed of vehicles with the highest accuracy is 97.52% and the lowest accuracy is 77.41%. And the detection results of testing by using real video footage on the road is included with real speed of the vehicle.

  4. Inspection vehicle

    International Nuclear Information System (INIS)

    Takahashi, Masaki; Omote, Tatsuyuki; Yoneya, Yutaka; Tanaka, Keiji; Waki, Tetsuro; Yoshida, Tomiji; Kido, Tsuyoshi.

    1993-01-01

    An inspection vehicle comprises a small-sized battery directly connected with a power motor or a direct power source from trolly lines and a switching circuit operated by external signals. The switch judges advance or retreat by two kinds of signals and the inspection vehicle is recovered by self-running. In order to recover the abnormally stopped inspection vehicle to the targeted place, the inspection vehicle is made in a free-running state by using a clutch mechanism and is pushed by an other vehicle. (T.M.)

  5. Stock return distribution in the BRICS

    Directory of Open Access Journals (Sweden)

    George Adu

    2015-12-01

    Full Text Available Stock returns in emerging market economies exhibit patterns that are distinctively different from developed countries: returns are noted to be highly volatile and autocorrelated, and long horizon returns are predictable. While these stylized facts are well established, the assumption underlying the distribution of returns is less understood. In particular, the empirical literature continues to rely on the normality assumption as a starting point, and most asset pricing models tend to overstretch this point. This paper questions the rationale behind this supposition and proceeds to test more formally for normality using multivariate joint test for skewness and kurtosis. Additionally, the paper extends the literature by examining a number of empirical regularities for Brazil, Russia, India, China and South Africa (the BRICS for short. Our main findings are that the distribution of stock returns for the BRICS exhibits peakedness with fatter and longer tails, and this is invariant to both the unit of measurement and the time horizon of returns. Volatility clustering is prevalent in all markets, and this decays exponentially for all but Brazil. The relationship between risk and return is found to be significant and risk premiums are prevalent in our sample.

  6. Risk-return of Belgian SRI funds

    OpenAIRE

    Van Liedekerke, Luc; De Moor, Lieven; Vanwalleghem, Dieter

    2007-01-01

    We analyse the risk-return profile of Belgian SRI funds versus conventional investment funds. We apply a four-factor conditional Carhart model to establish whether there are significant differences in risk-return profile between an SRI portfolio and a conventional portfolio and test for learning effects in SRI funds. We show that there is no difference in risk-return profile between SRI and conventional funds. If return is not the problem, then what is it that limits the development of an SRI...

  7. In-vehicle information system functions

    Energy Technology Data Exchange (ETDEWEB)

    Tufano, D.R.; Spelt, P.F.; Knee, H.E.

    1997-04-01

    This paper describes the functional requirement for an In-Vehicle Information System (IVIS), which will manage and display all driving-related information from many sources. There are numerous information systems currently being fielded or developed (e.g., routing and navigation, collision avoidance). However, without a logical integration of all of the possible on-board information, there is a potential for overwhelming the driver. The system described in this paper will filter and prioritize information across all sources, and present it to the driver in a timely manner, within a unified interface. To do this, IVIS will perform three general functions: (1) interact with other, on-board information subsystems and the vehicle; (2) manage the information by filtering, prioritizing, and integrating it; and (3) interact with the driver, both in terms of displaying information to the driver and allowing the driver to input requests, goals and preferences. The functional requirements described in this paper have either been derived from these three high-level functions or are directly mandated by the overriding requirements for modularity and flexibility. IVIS will have to be able to accommodate different types of information subsystems, of varying level of sophistication. The system will also have to meet the diverse needs of different types of drivers (private, commercial, transit), who may have very different levels of expertise in using information systems.

  8. Input and execution

    International Nuclear Information System (INIS)

    Carr, S.; Lane, G.; Rowling, G.

    1986-11-01

    This document describes the input procedures, input data files and operating instructions for the SYVAC A/C 1.03 computer program. SYVAC A/C 1.03 simulates the groundwater mediated movement of radionuclides from underground facilities for the disposal of low and intermediate level wastes to the accessible environment, and provides an estimate of the subsequent radiological risk to man. (author)

  9. Traffic Information Unit, Traffic Information System, Vehicle Management System, Vehicle, and Method of Controlling a Vehicle

    NARCIS (Netherlands)

    Papp, Z.; Doodeman, G.J.N.; Nelisse, M.W.; Sijs, J.; Theeuwes, J.A.C.; Driessen, B.J.F.

    2010-01-01

    A traffic information unit (MD1, MD2, MD3) according to the invention comprises a facility (MI) for tracking vehicle state information of individual vehicles present at a traffic infrastructure and a facility (T) for transmitting said vehicle state information to a vehicle (70B, 70E). A traffic

  10. Overcoming the Range Limitation of Medium-Duty Battery Electric Vehicles through the use of Hydrogen Fuel-Cells

    Energy Technology Data Exchange (ETDEWEB)

    Wood, E.; Wang, L.; Gonder, J.; Ulsh, M.

    2013-10-01

    Battery electric vehicles possess great potential for decreasing lifecycle costs in medium-duty applications, a market segment currently dominated by internal combustion technology. Characterized by frequent repetition of similar routes and daily return to a central depot, medium-duty vocations are well positioned to leverage the low operating costs of battery electric vehicles. Unfortunately, the range limitation of commercially available battery electric vehicles acts as a barrier to widespread adoption. This paper describes the National Renewable Energy Laboratory's collaboration with the U.S. Department of Energy and industry partners to analyze the use of small hydrogen fuel-cell stacks to extend the range of battery electric vehicles as a means of improving utility, and presumably, increasing market adoption. This analysis employs real-world vocational data and near-term economic assumptions to (1) identify optimal component configurations for minimizing lifecycle costs, (2) benchmark economic performance relative to both battery electric and conventional powertrains, and (3) understand how the optimal design and its competitiveness change with respect to duty cycle and economic climate. It is found that small fuel-cell power units provide extended range at significantly lower capital and lifecycle costs than additional battery capacity alone. And while fuel-cell range-extended vehicles are not deemed economically competitive with conventional vehicles given present-day economic conditions, this paper identifies potential future scenarios where cost equivalency is achieved.

  11. Vehicle Tracking System, Vehicle Infrastructure Provided with Vehicle Tracking System and Method for Tracking

    NARCIS (Netherlands)

    Papp, Z.; Doodeman, G.J.N.; Nelisse, M.W.; Sijs, J.; Theeuwes, J.A.C.; Driessen, B.J.F.

    2010-01-01

    A vehicle tracking system is described comprising - a plurality of sensor nodes (10) that each provide a message (D) indicative for an occupancy status of a detection area of an vehicle infrastructure monitored by said sensor node, said sensor nodes (10) being arranged in the vehicle infrastructure

  12. 7 CFR 3560.305 - Return on investment.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Return on investment. 3560.305 Section 3560.305... AGRICULTURE DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Financial Management § 3560.305 Return on investment. (a) Borrower's return on investment. Borrowers may receive a return on their investment (ROI) in...

  13. Characteristics of donors who do or do not return to give blood and barriers to their return

    Science.gov (United States)

    Wevers, Anne; Wigboldus, Daniël H.J.; de Kort, Wim L.A.M.; van Baaren, Rick; Veldhuizen, Ingrid J.T.

    2014-01-01

    Background In the Netherlands about 50% of whole blood donors return to give blood after an invitation to donate. This study aimed to investigate the characteristics of donor return behaviour and to gain insight into the barriers to blood donation reported by the donors themselves. Materials and methods A total of 4,901 whole blood donors were invited to donate in week 39 of 2009. Barriers mentioned by donors who informed the blood bank for not donating were registered for 1 month. Logistic regression analyses assessed relevant characteristics of return behaviour, such as age and blood type, in men and women separately. Results Of the invited donors, 55% returned to give a donation, whereas 45% did not return. Male donors were more likely to return when they were older, had a higher previous return rate and had no past deferrals. The same pattern was found among women, but was less strong. The main barriers were: time constraints (35%), preference to postpone donation due to general physical problems although being eligible to donate (29%), and being ineligible to donate due to medical deferral criteria (9%). Discussion Specific donor characteristics are associated with return behaviour. Not donating due to time constraints could mean that donors do not feel the urgency of donating blood. Interventions targeted to increase commitment among specific donor groups should be tested further. PMID:23522891

  14. A Concept of Two-Stage-To-Orbit Reusable Launch Vehicle

    Science.gov (United States)

    Yang, Yong; Wang, Xiaojun; Tang, Yihua

    2002-01-01

    Reusable Launch Vehicle (RLV) has a capability of delivering a wide rang of payload to earth orbit with greater reliability, lower cost, more flexibility and operability than any of today's launch vehicles. It is the goal of future space transportation systems. Past experience on single stage to orbit (SSTO) RLVs, such as NASA's NASP project, which aims at developing an rocket-based combined-cycle (RBCC) airplane and X-33, which aims at developing a rocket RLV, indicates that SSTO RLV can not be realized in the next few years based on the state-of-the-art technologies. This paper presents a concept of all rocket two-stage-to-orbit (TSTO) reusable launch vehicle. The TSTO RLV comprises an orbiter and a booster stage. The orbiter is mounted on the top of the booster stage. The TSTO RLV takes off vertically. At the altitude about 50km the booster stage is separated from the orbiter, returns and lands by parachutes and airbags, or lands horizontally by means of its own propulsion system. The orbiter continues its ascent flight and delivers the payload into LEO orbit. After completing orbit mission, the orbiter will reenter into the atmosphere, automatically fly to the ground base and finally horizontally land on the runway. TSTO RLV has less technology difficulties and risk than SSTO, and maybe the practical approach to the RLV in the near future.

  15. Measuring aerosols generated inside armoured vehicles perforated by depleted uranium ammunition

    International Nuclear Information System (INIS)

    Parkhurst, M.A.

    2003-01-01

    In response to questions raised after the Gulf War about the health significance of exposure to depleted uranium (DU), the US Department of Defense initiated a study designed to provide an improved scientific basis for assessment of possible health effects on soldiers in vehicles struck by these munitions. As part of this study, a series of DU penetrators were fired at an Abrams tank and a Bradley fighting vehicle, and the aerosols generated by vehicle perforation were collected and characterised. A robust sampling system was designed to collect aerosols in this difficult environment and monitor continuously the sampler flow rates. The aerosol samplers selected for these tests included filter cassettes, cascade impactors, a five-stage cyclone and a moving filter. Sampler redundancy was an integral part of the sampling system to offset losses from fragment damage. Wipe surveys and deposition trays collected removable deposited particulate matter. Interior aerosols were analysed for uranium concentration and particle size distribution as a function of time. They were also analysed for uranium oxide phases, particle morphology and dissolution in vitro. These data, currently under independent peer review, will provide input for future prospective and retrospective dose and health risk assessments of inhaled or ingested DU aerosols. This paper briefly discusses the target vehicles, firing trajectories, aerosol samplers and instrumentation control systems, and the types of analyses conducted on the samples. (author)

  16. Money growth and aggregate stock returns

    OpenAIRE

    Böing, Tobias; Stadtmann, Georg

    2016-01-01

    We empirically evaluate the predictive power of money growth measured by M2 for stock returns of the S&P 500 index. We use monthly US data and predict multiperiod returns over 1, 3, and 5 years with long-horizon regressions. In-sample regressions show that money growth is useful for predicting returns. Higher recent money growth has a significantly negative effect on subsequent returns of the S&P 500. An out-of-sample analysis shows that a simple model with money growth as a single predictor ...

  17. Poetic Return in Afghanistan Persian Poem

    Directory of Open Access Journals (Sweden)

    Esmaeil Shafagh

    2012-11-01

    Full Text Available Abstract Poetic return movement was started by a group of poets like Moshtagh and Shole Esfehani in the second half of 12 century. Their goal was restoring Persian poem and deliverance of Hindi style decline. Esfahan’s poets initiative was considered only in Iran but in other Persian language and literature areas like India, Afghanistan and Transoxiana it was ignored. After the failure of constitutional Movement in Afghanistan, motion similar poetic return was happened that caused poetic themes, which had gone towards modernism, return to Hindi style again.The present paper attempts to analyze the poetic atmosphere in Afghanistan synchronous the poetic return movement in Iran and investigate socio- political backgrounds of return to Hindi style in Afghanistan after constitution failure.

  18. Automated space vehicle control for rendezvous proximity operations

    Science.gov (United States)

    Lea, Robert N.

    1988-01-01

    Rendezvous during the unmanned space exploration missions, such as a Mars Rover/Sample Return will require a completely automatic system from liftoff to docking. A conceptual design of an automated rendezvous, proximity operations, and docking system is being implemented and validated at the Johnson Space Center (JSC). The emphasis is on the progress of the development and testing of a prototype system for control of the rendezvous vehicle during proximity operations that is currently being developed at JSC. Fuzzy sets are used to model the human capability of common sense reasoning in decision making tasks and such models are integrated with the expert systems and engineering control system technology to create a system that performs comparably to a manned system.

  19. Vehicle accelerated corrosion test procedures for automotive in Malaysia

    Directory of Open Access Journals (Sweden)

    Anuar Liza

    2017-01-01

    Full Text Available An accelerated corrosion test, known as proving ground accelerated test, is commonly performed by automotive manufacturers to evaluate the corrosion performance of a vehicle. The test combines corrosion and durability inputs to detect potential failures that may occur during in-service conditions. Currently, the test is conducted at an external test center overseas. Such test is aimed to simulate the effects of one year accelerated corrosion in severe corrosive environment of the north-east and south east of America. However, the test results obtained do not correlate with the actual corrosion conditions observed in the Malaysian market, which is likely attributed to the different test environment of the tropical climate of vehicles in service. Therefore, a vehicle accelerated corrosion test procedure that suits the Malaysian market is proposed and benchmarked with other global car manufacturers that have their own dedicated corrosion test procedure. In the present work, a test track is used as the corrosion test ground and consists of various types of roads for structural durability exposures. Corrosion related facilities like salt trough, mud trough and gravel road are constructed as addition to the existing facilities. The establishment of accelerated corrosion test facilities has contributed to the development of initial accelerated corrosion test procedure for the national car manufacturer. The corrosion exposure is monitored by fitting test coupons at the underbody of test vehicle using mass loss technique so that the desired corrosion rate capable of simulating the real time corrosion effects for its target market.

  20. Spectral analysis methods for vehicle interior vibro-acoustics identification

    Science.gov (United States)

    Hosseini Fouladi, Mohammad; Nor, Mohd. Jailani Mohd.; Ariffin, Ahmad Kamal

    2009-02-01

    Noise has various effects on comfort, performance and health of human. Sound are analysed by human brain based on the frequencies and amplitudes. In a dynamic system, transmission of sound and vibrations depend on frequency and direction of the input motion and characteristics of the output. It is imperative that automotive manufacturers invest a lot of effort and money to improve and enhance the vibro-acoustics performance of their products. The enhancement effort may be very difficult and time-consuming if one relies only on 'trial and error' method without prior knowledge about the sources itself. Complex noise inside a vehicle cabin originated from various sources and travel through many pathways. First stage of sound quality refinement is to find the source. It is vital for automotive engineers to identify the dominant noise sources such as engine noise, exhaust noise and noise due to vibration transmission inside of vehicle. The purpose of this paper is to find the vibro-acoustical sources of noise in a passenger vehicle compartment. The implementation of spectral analysis method is much faster than the 'trial and error' methods in which, parts should be separated to measure the transfer functions. Also by using spectral analysis method, signals can be recorded in real operational conditions which conduce to more consistent results. A multi-channel analyser is utilised to measure and record the vibro-acoustical signals. Computational algorithms are also employed to identify contribution of various sources towards the measured interior signal. These achievements can be utilised to detect, control and optimise interior noise performance of road transport vehicles.

  1. Magnetic Field Emission Comparison for Series-Parallel and Series-Series Wireless Power Transfer to Vehicles – PART 2/2

    DEFF Research Database (Denmark)

    Batra, Tushar; Schaltz, Erik

    2014-01-01

    Series-series and series-parallel topologies are the most favored topologies for design of wireless power transfer system for vehicle applications. The series-series topology has the advantage of reflecting only the resistive part on the primary side. On the other hand, the current source output...... characteristics of the series-parallel topology are more suited for the battery of the vehicle. This paper compares the two topologies in terms of magnetic emissions to the surroundings for the same input power, primary current, quality factor and inductors. Theoretical and simulation results show that the series...

  2. PLEXOS Input Data Generator

    Energy Technology Data Exchange (ETDEWEB)

    2017-02-01

    The PLEXOS Input Data Generator (PIDG) is a tool that enables PLEXOS users to better version their data, automate data processing, collaborate in developing inputs, and transfer data between different production cost modeling and other power systems analysis software. PIDG can process data that is in a generalized format from multiple input sources, including CSV files, PostgreSQL databases, and PSS/E .raw files and write it to an Excel file that can be imported into PLEXOS with only limited manual intervention.

  3. Common Factors in International Bond Returns

    NARCIS (Netherlands)

    Driessen, J.J.A.G.; Melenberg, B.; Nijman, T.E.

    2000-01-01

    In this paper we estimate and interpret the factors that jointly determine bond returns of different maturities in the US, Germany and Japan.We analyze both currency-hedged and unhedged bond returns.For currency-hedged bond returns, we find that five factors explain 96.5% of the variation of bond

  4. Development of database of real-world diesel vehicle emission factors for China.

    Science.gov (United States)

    Shen, Xianbao; Yao, Zhiliang; Zhang, Qiang; Wagner, David Vance; Huo, Hong; Zhang, Yingzhi; Zheng, Bo; He, Kebin

    2015-05-01

    A database of real-world diesel vehicle emission factors, based on type and technology, has been developed following tests on more than 300 diesel vehicles in China using a portable emission measurement system. The database provides better understanding of diesel vehicle emissions under actual driving conditions. We found that although new regulations have reduced real-world emission levels of diesel trucks and buses significantly for most pollutants in China, NOx emissions have been inadequately controlled by the current standards, especially for diesel buses, because of bad driving conditions in the real world. We also compared the emission factors in the database with those calculated by emission factor models and used in inventory studies. The emission factors derived from COPERT (Computer Programmer to calculate Emissions from Road Transport) and MOBILE may both underestimate real emission factors, whereas the updated COPERT and PART5 (Highway Vehicle Particulate Emission Modeling Software) models may overestimate emission factors in China. Real-world measurement results and emission factors used in recent emission inventory studies are inconsistent, which has led to inaccurate estimates of emissions from diesel trucks and buses over recent years. This suggests that emission factors derived from European or US-based models will not truly represent real-world emissions in China. Therefore, it is useful and necessary to conduct systematic real-world measurements of vehicle emissions in China in order to obtain the optimum inputs for emission inventory models. Copyright © 2015. Published by Elsevier B.V.

  5. Return-to-work coordination programmes for improving return to work in workers on sick leave.

    Science.gov (United States)

    Vogel, Nicole; Schandelmaier, Stefan; Zumbrunn, Thomas; Ebrahim, Shanil; de Boer, Wout El; Busse, Jason W; Kunz, Regina

    2017-03-30

    To limit long-term sick leave and associated consequences, insurers, healthcare providers and employers provide programmes to facilitate disabled people's return to work. These programmes include a variety of coordinated and individualised interventions. Despite the increasing popularity of such programmes, their benefits remain uncertain. We conducted a systematic review to determine the long-term effectiveness of return-to-work coordination programmes compared to usual practice in workers at risk for long-term disability. To assess the effects of return-to-work coordination programmes versus usual practice for workers on sick leave or disability. We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 11), MEDLINE, Embase, CINAHL and PsycINFO up to 1 November 2016. We included randomised controlled trials (RCTs) that enrolled workers absent from work for at least four weeks and randomly assigned them to return-to-work coordination programmes or usual practice. Two review authors independently screened titles, abstracts and full-text articles for study eligibility; extracted data; and assessed risk of bias from eligible trials. We contacted authors for additional data where required. We conducted random-effects meta-analyses and used the GRADE approach to rate the quality of the evidence. We identified 14 studies from nine countries that enrolled 12,568 workers. Eleven studies focused on musculoskeletal problems, two on mental health and one on both. Most studies (11 of 14) followed workers 12 months or longer. Risk of bias was low in 10 and high in 4 studies, but findings were not sensitive to their exclusion.We found no benefits for return-to-work coordination programmes on return-to-work outcomes.For short-term follow-up of six months, we found no effect on time to return to work (hazard ratio (HR) 1.32, 95% confidence interval (CI) 0.93 to 1.88, low-quality evidence), cumulative sickness absence (mean difference (MD) -16.18 work

  6. How important is vehicle safety in the new vehicle purchase process?

    Science.gov (United States)

    Koppel, Sjaanie; Charlton, Judith; Fildes, Brian; Fitzharris, Michael

    2008-05-01

    Whilst there has been a significant increase in the amount of consumer interest in the safety performance of privately owned vehicles, the role that it plays in consumers' purchase decisions is poorly understood. The aims of the current study were to determine: how important vehicle safety is in the new vehicle purchase process; what importance consumers place on safety options/features relative to other convenience and comfort features, and how consumers conceptualise vehicle safety. In addition, the study aimed to investigate the key parameters associated with ranking 'vehicle safety' as the most important consideration in the new vehicle purchase. Participants recruited in Sweden and Spain completed a questionnaire about their new vehicle purchase. The findings from the questionnaire indicated that participants ranked safety-related factors (e.g., EuroNCAP (or other) safety ratings) as more important in the new vehicle purchase process than other vehicle factors (e.g., price, reliability etc.). Similarly, participants ranked safety-related features (e.g., advanced braking systems, front passenger airbags etc.) as more important than non-safety-related features (e.g., route navigation systems, air-conditioning etc.). Consistent with previous research, most participants equated vehicle safety with the presence of specific vehicle safety features or technologies rather than vehicle crash safety/test results or crashworthiness. The key parameters associated with ranking 'vehicle safety' as the most important consideration in the new vehicle purchase were: use of EuroNCAP, gender and education level, age, drivers' concern about crash involvement, first vehicle purchase, annual driving distance, person for whom the vehicle was purchased, and traffic infringement history. The findings from this study are important for policy makers, manufacturers and other stakeholders to assist in setting priorities with regard to the promotion and publicity of vehicle safety features

  7. Solid Particle Number Emission Factors of Euro VI Heavy-Duty Vehicles on the Road and in the Laboratory

    Science.gov (United States)

    Giechaskiel, Barouch

    2018-01-01

    Particulate matter (PM), and in particular ultrafine particles, have a negative impact on human health. The contribution of vehicle PM emissions to air pollution is typically quantified with emission inventories, which need vehicle emission factors as input. Heavy-duty vehicles, although they represent a small percentage of the vehicle population in nearly every major country, contribute the majority of the on-road PM emissions. However, the published data of modern heavy-duty vehicle emissions are scarce, and for the newest Euro VI technologies, almost non-existent. The main objective of this paper is to present Solid Particle Number (SPN) emission factors from Euro VI heavy-duty vehicles using diesel, Compressed Natural Gas (CNG), or Liquefied Natural Gas (LNG). Urban, rural and motorway (highway) emissions were determined on the road at various European cities using SPN Portable Emission Measurement Systems (PEMS). Additional tests on a heavy-duty chassis dynamometer showed that the solid sub-23 nm fraction, which is not covered at the moment in the European regulation, is high, especially for CNG engines. The significant contribution of regeneration events and the effect of ambient temperature and engine cold-start on particle emissions were also discussed. PMID:29425174

  8. Solid Particle Number Emission Factors of Euro VI Heavy-Duty Vehicles on the Road and in the Laboratory

    Directory of Open Access Journals (Sweden)

    Barouch Giechaskiel

    2018-02-01

    Full Text Available Particulate matter (PM, and in particular ultrafine particles, have a negative impact on human health. The contribution of vehicle PM emissions to air pollution is typically quantified with emission inventories, which need vehicle emission factors as input. Heavy-duty vehicles, although they represent a small percentage of the vehicle population in nearly every major country, contribute the majority of the on-road PM emissions. However, the published data of modern heavy-duty vehicle emissions are scarce, and for the newest Euro VI technologies, almost non-existent. The main objective of this paper is to present Solid Particle Number (SPN emission factors from Euro VI heavy-duty vehicles using diesel, Compressed Natural Gas (CNG, or Liquefied Natural Gas (LNG. Urban, rural and motorway (highway emissions were determined on the road at various European cities using SPN Portable Emission Measurement Systems (PEMS. Additional tests on a heavy-duty chassis dynamometer showed that the solid sub-23 nm fraction, which is not covered at the moment in the European regulation, is high, especially for CNG engines. The significant contribution of regeneration events and the effect of ambient temperature and engine cold-start on particle emissions were also discussed.

  9. Solid Particle Number Emission Factors of Euro VI Heavy-Duty Vehicles on the Road and in the Laboratory.

    Science.gov (United States)

    Giechaskiel, Barouch

    2018-02-09

    Particulate matter (PM), and in particular ultrafine particles, have a negative impact on human health. The contribution of vehicle PM emissions to air pollution is typically quantified with emission inventories, which need vehicle emission factors as input. Heavy-duty vehicles, although they represent a small percentage of the vehicle population in nearly every major country, contribute the majority of the on-road PM emissions. However, the published data of modern heavy-duty vehicle emissions are scarce, and for the newest Euro VI technologies, almost non-existent. The main objective of this paper is to present Solid Particle Number (SPN) emission factors from Euro VI heavy-duty vehicles using diesel, Compressed Natural Gas (CNG), or Liquefied Natural Gas (LNG). Urban, rural and motorway (highway) emissions were determined on the road at various European cities using SPN Portable Emission Measurement Systems (PEMS). Additional tests on a heavy-duty chassis dynamometer showed that the solid sub-23 nm fraction, which is not covered at the moment in the European regulation, is high, especially for CNG engines. The significant contribution of regeneration events and the effect of ambient temperature and engine cold-start on particle emissions were also discussed.

  10. Measuring the Impact of Economic Crisis to the Greek Vehicle Market

    Directory of Open Access Journals (Sweden)

    Evanthia A. Nanaki

    2018-02-01

    Full Text Available The fallout of the global economic crisis has impacted Greece severely as the austerity measures that were implemented since 2009 have had a devastating effect on poverty and the level of living. The financial agreement of the Greek government with the International Monetary Fund (IMF gave rise to a deep recession phase in the Greek market that started in early 2008. The automobile industry is among the sectors that have been severely affected by the economic crisis. Given that the demand for cars fell sharply and that the Greek car market is facing serious problems, mapping and understanding them can provide useful input to the Greek vehicle market. Regression analysis is being employed, and the interrelations of different variables, such as net disposable income, unemployment rate, fuel prices, the Greek crisis, loans directed to the vehicle market, as well as the inflation rate for the period of 2000–2016, are investigated. Analyzing the factors affecting car sales can provide policy-makers with knowledge in order to take legislative and economic measures, so as to boost sales of new environmental friendly vehicles not only in Greece, but in all EU states.

  11. Thermal simulation of a cooling system of hybrid commercial vehicles; Thermalsimulation eine Hybrid-LKW-Kuehlsystems

    Energy Technology Data Exchange (ETDEWEB)

    Stroh, Christoph; Schnoerch, Stefan; Rathberger, Christian [Magna Powertrain Engineering Center Steyr GmbH und Co. KG, St. Valentin (Austria)

    2012-11-01

    In the past few years hybrid vehicles have been in the center of automotive engineering efforts, in particular in the field of passenger cars. But hybrid powertrains will also be important for commercial trucks. This focus on hybrid vehicles leads to high demands on thermal management since the additional components in a hybrid vehicle need appropriate cooling or even heating. In the given paper the simulation of a complete cooling system of a hybrid commercial vehicle will be explained. For this virtual examination the commercial 1D thermal management software KULI will be used, a co-simulation with several programs will not be done deliberately. Yet all aspects which are relevant for a global assessment of the thermal management are considered. The main focus is put on the investigation of appropriate concepts for the fluid circuits, including low and high temperature circuits, electric water pumps, etc. Moreover, also a refrigerant circuit with a chiller for active battery cooling will be used, the appropriate control strategy is implemented as well. For simulating transient profiles a simple driving simulation model is included, using road profile, ambient conditions, and various vehicle parameters as input. In addition an engine model is included which enables the investigation of fuel consumption potentials. This simulation model shows how the thermal management of a hybrid vehicle can be investigated with a single program and with reasonable effort. (orig.)

  12. 26 CFR 301.6103(n)-1 - Disclosure of returns and return information in connection with written contracts or agreements...

    Science.gov (United States)

    2010-04-01

    ... administration purposes. 301.6103(n)-1 Section 301.6103(n)-1 Internal Revenue INTERNAL REVENUE SERVICE... and Returns Returns and Records § 301.6103(n)-1 Disclosure of returns and return information in... administration purposes. (a) General rule. (1) Pursuant to the provisions of section 6103(n) of the Internal...

  13. Particle bed reactor propulsion vehicle performance and characteristics as an orbital transfer rocket

    International Nuclear Information System (INIS)

    Horn, F.L.; Powell, J.R.; Lazareth, O.W.

    1986-01-01

    The particle bed reactor designed for 100 to 300 MW power output using hydrogen as a coolant is capable of specific impulses up to 1000 seconds as a nuclear rocket. A single space shuttle compatible vehicle can perform extensive missions from LEO to 3 times GEO and return with multi-ton payloads. The use of hydrogen to directly cool particulate reactor fuel results in a compact, lightweight rocket vehicle, whose duration of usefulness is dependent only upon hydrogen resupply availability. The LEO to GEO mission had a payload capability of 15.4 metric tons with 3.4 meters of shuttle bay. To increase the volume limitation of the shuttle bay, the use of ammonia in the initial boost phase from LEO is used to give greater payload volume with a small decrease in payload mass, 8.7 meters and 12.7 m-tons. 5 refs., 15 figs

  14. Network synthesis and parameter optimization for vehicle suspension with inerter

    Directory of Open Access Journals (Sweden)

    Long Chen

    2016-12-01

    Full Text Available In order to design a comfortable-oriented vehicle suspension structure, the network synthesis method was utilized to transfer the problem into solving a timing robust control problem and determine the structure of “inerter–spring–damper” suspension. Bilinear Matrix Inequality was utilized to obtain the timing transfer function. Then, the transfer function of suspension system can be physically implemented by passive elements such as spring, damper, and inerter. By analyzing the sensitivity and quantum genetic algorithm, the optimized parameters of inerter–spring–damper suspension were determined. A quarter-car model was established. The performance of the inerter–spring–damper suspension was verified under random input. The simulation results manifested that the dynamic performance of the proposed suspension was enhanced in contrast with traditional suspension. The root mean square of vehicle body acceleration decreases by 18.9%. The inerter–spring–damper suspension can inhibit the vertical vibration within the frequency of 1–3 Hz effectively and enhance the performance of ride comfort significantly.

  15. Dynamic Surface Control and Its Application to Lateral Vehicle Control

    Directory of Open Access Journals (Sweden)

    Bongsob Song

    2014-01-01

    Full Text Available This paper extends the design and analysis methodology of dynamic surface control (DSC in Song and Hedrick, 2011, for a more general class of nonlinear systems. When rotational mechanical systems such as lateral vehicle control and robot control are considered for applications, sinusoidal functions are easily included in the equation of motions. If such a sinusoidal function is used as a forcing term for DSC, the stability analysis faces the difficulty due to highly nonlinear functions resulting from the low-pass filter dynamics. With modification of input variables to the filter dynamics, the burden of mathematical analysis can be reduced and stability conditions in linear matrix inequality form to guarantee the quadratic stability via DSC are derived for the given class of nonlinear systems. Finally, the proposed design and analysis approach are applied to lateral vehicle control for forward automated driving and backward parallel parking at a low speed as well as an illustrative example.

  16. Application of Fault Management Theory to the Quantitative Selection of a Launch Vehicle Abort Trigger Suite

    Science.gov (United States)

    Lo, Yunnhon; Johnson, Stephen B.; Breckenridge, Jonathan T.

    2014-01-01

    The theory of System Health Management (SHM) and of its operational subset Fault Management (FM) states that FM is implemented as a "meta" control loop, known as an FM Control Loop (FMCL). The FMCL detects that all or part of a system is now failed, or in the future will fail (that is, cannot be controlled within acceptable limits to achieve its objectives), and takes a control action (a response) to return the system to a controllable state. In terms of control theory, the effectiveness of each FMCL is estimated based on its ability to correctly estimate the system state, and on the speed of its response to the current or impending failure effects. This paper describes how this theory has been successfully applied on the National Aeronautics and Space Administration's (NASA) Space Launch System (SLS) Program to quantitatively estimate the effectiveness of proposed abort triggers so as to select the most effective suite to protect the astronauts from catastrophic failure of the SLS. The premise behind this process is to be able to quantitatively provide the value versus risk trade-off for any given abort trigger, allowing decision makers to make more informed decisions. All current and planned crewed launch vehicles have some form of vehicle health management system integrated with an emergency launch abort system to ensure crew safety. While the design can vary, the underlying principle is the same: detect imminent catastrophic vehicle failure, initiate launch abort, and extract the crew to safety. Abort triggers are the detection mechanisms that identify that a catastrophic launch vehicle failure is occurring or is imminent and cause the initiation of a notification to the crew vehicle that the escape system must be activated. While ensuring that the abort triggers provide this function, designers must also ensure that the abort triggers do not signal that a catastrophic failure is imminent when in fact the launch vehicle can successfully achieve orbit. That is

  17. Vision-Based Leader Vehicle Trajectory Tracking for Multiple Agricultural Vehicles.

    Science.gov (United States)

    Zhang, Linhuan; Ahamed, Tofael; Zhang, Yan; Gao, Pengbo; Takigawa, Tomohiro

    2016-04-22

    The aim of this study was to design a navigation system composed of a human-controlled leader vehicle and a follower vehicle. The follower vehicle automatically tracks the leader vehicle. With such a system, a human driver can control two vehicles efficiently in agricultural operations. The tracking system was developed for the leader and the follower vehicle, and control of the follower was performed using a camera vision system. A stable and accurate monocular vision-based sensing system was designed, consisting of a camera and rectangular markers. Noise in the data acquisition was reduced by using the least-squares method. A feedback control algorithm was used to allow the follower vehicle to track the trajectory of the leader vehicle. A proportional-integral-derivative (PID) controller was introduced to maintain the required distance between the leader and the follower vehicle. Field experiments were conducted to evaluate the sensing and tracking performances of the leader-follower system while the leader vehicle was driven at an average speed of 0.3 m/s. In the case of linear trajectory tracking, the RMS errors were 6.5 cm, 8.9 cm and 16.4 cm for straight, turning and zigzag paths, respectively. Again, for parallel trajectory tracking, the root mean square (RMS) errors were found to be 7.1 cm, 14.6 cm and 14.0 cm for straight, turning and zigzag paths, respectively. The navigation performances indicated that the autonomous follower vehicle was able to follow the leader vehicle, and the tracking accuracy was found to be satisfactory. Therefore, the developed leader-follower system can be implemented for the harvesting of grains, using a combine as the leader and an unloader as the autonomous follower vehicle.

  18. SSYST-3. Input description

    International Nuclear Information System (INIS)

    Meyder, R.

    1983-12-01

    The code system SSYST-3 is designed to analyse the thermal and mechanical behaviour of a fuel rod during a LOCA. The report contains a complete input-list for all modules and several tested inputs for a LOCA analysis. (orig.)

  19. Does Driving Range of Electric Vehicles Influence Electric Vehicle Adoption?

    Directory of Open Access Journals (Sweden)

    Seiho Kim

    2017-10-01

    Full Text Available This study aims to determine the influential factors on the market share of electric vehicles through panel data analysis based on time series data from 2011 to 2015 in 31 countries. We selected five significant independent variables that are expected to affect electric vehicle adoption based on literature review. The econometric model in this study suggests that the relative price of electric vehicle compared to internal combustion engine vehicle, driving range, and number of models available in markets are correlated to the market share of electric vehicles. On the other hand, relationship between recharging infrastructure—an important factor for electric vehicle adoption in many studies—and market share of electric vehicles turned out to be insignificant in this study. From a political point of view, we argue that policy makers need to allocate more resources to research and development in order to extend driving range at the early stage of electric vehicle deployment in the markets.

  20. Isotopic signatures of eelgrass (Zostera marina L.) as bioindicator of anthropogenic nutrient input in the western Baltic Sea

    International Nuclear Information System (INIS)

    Schubert, Philipp R.; Karez, Rolf; Reusch, Thorsten B.H.; Dierking, Jan

    2013-01-01

    Highlights: • Anthropogenic nitrogen (N) inputs are a global problem, but difficult to quantify. • We tested the use of eelgrass δ 15 N as proxy of such inputs in the Baltic Sea. • The method revealed distinct spatial patterns in sewage N across a eutrophic bay. • Traditional eutrophication measures corroborated the results from δ 15 N values. • Eelgrass δ 15 N ratios have high potential as proxy of sewage-derived N in the Baltic. -- Abstract: Eutrophication is a global environmental problem. Better management of this threat requires more accurate assessments of anthropogenic nitrogen (N) inputs to coastal systems than can be obtained with traditional measures. Recently, primary producer N isotopic signatures have emerged as useful proxy of such inputs. Here, we demonstrated for the first time the applicability of this method using the widespread eelgrass (Zostera marina) in the highly eutrophic Baltic Sea. Spatial availability of sewage N across a bay with one major sewage outflow predicted by eelgrass δ 15 N was high near and downstream of the outflow compared to upstream, but returned to upstream levels within 4 km downstream from the outfall. General conclusions were corroborated by traditional eutrophication measures, but in contrast to these measures were fully quantitative. Eelgrass N isotope ratios therefore show high potential for coastal screens of eutrophication in the Baltic Sea, and in other areas with eelgrass meadows

  1. Material input of nuclear fuel

    International Nuclear Information System (INIS)

    Rissanen, S.; Tarjanne, R.

    2001-01-01

    The Material Input (MI) of nuclear fuel, expressed in terms of the total amount of natural material needed for manufacturing a product, is examined. The suitability of the MI method for assessing the environmental impacts of fuels is also discussed. Material input is expressed as a Material Input Coefficient (MIC), equalling to the total mass of natural material divided by the mass of the completed product. The material input coefficient is, however, only an intermediate result, which should not be used as such for the comparison of different fuels, because the energy contents of nuclear fuel is about 100 000-fold compared to the energy contents of fossil fuels. As a final result, the material input is expressed in proportion to the amount of generated electricity, which is called MIPS (Material Input Per Service unit). Material input is a simplified and commensurable indicator for the use of natural material, but because it does not take into account the harmfulness of materials or the way how the residual material is processed, it does not alone express the amount of environmental impacts. The examination of the mere amount does not differentiate between for example coal, natural gas or waste rock containing usually just sand. Natural gas is, however, substantially more harmful for the ecosystem than sand. Therefore, other methods should also be used to consider the environmental load of a product. The material input coefficient of nuclear fuel is calculated using data from different types of mines. The calculations are made among other things by using the data of an open pit mine (Key Lake, Canada), an underground mine (McArthur River, Canada) and a by-product mine (Olympic Dam, Australia). Furthermore, the coefficient is calculated for nuclear fuel corresponding to the nuclear fuel supply of Teollisuuden Voima (TVO) company in 2001. Because there is some uncertainty in the initial data, the inaccuracy of the final results can be even 20-50 per cent. The value

  2. A Department of Motor Vehicle-Based Intervention to Promote Organ Donor Registrations in New York State.

    Science.gov (United States)

    Feeley, Thomas Hugh; Anker, Ashley E; Evans, Melanie; Reynolds-Tylus, Tobias

    2017-09-01

    Examination of efficacy of motor vehicle representative educational training and dissemination of promotional materials as a means to promote organ donation enrollments in New York State. To increase the number of New York State residents who consent to donation through the department of motor vehicle transactions during project period. County-run motor vehicle offices across New York State. Customers who present to New York Department of Motor Vehicle offices and the representative who work at designated bureaus. point-of-decision materials including promotional posters, brochures, website, and the motor vehicle representative training sessions. Reasons for enrollment decision, knowledge/experience with donation, monthly consent rates, enrollment in state organ, and tissue registry. Customers who elected not to register reported no reason or uncertainty surrounding enrollment. The representatives reported experience with donation, discussion with customers, and need for additional education on organ donation. Enrollment cards were mailed to 799 project staff; counties where offices participated in intervention did not indicate significantly higher monthly enrollments when comparing pre- to postenrollment rates. Use of point-of-decision materials and enrollment cards proved inexpensive method to register customers with a 3.6% return rate. Customers report low (27%) enrollment rate and reticence to consent to donation. Educational training sessions with representatives did not yield significant enrollment increases when evaluating data at county-level enrollment.

  3. Hierarchical Control Strategy for Active Hydropneumatic Suspension Vehicles Based on Genetic Algorithms

    Directory of Open Access Journals (Sweden)

    Jinzhi Feng

    2015-02-01

    Full Text Available A new hierarchical control strategy for active hydropneumatic suspension systems is proposed. This strategy considers the dynamic characteristics of the actuator. The top hierarchy controller uses a combined control scheme: a genetic algorithm- (GA- based self-tuning proportional-integral-derivative controller and a fuzzy logic controller. For practical implementations of the proposed control scheme, a GA-based self-learning process is initiated only when the defined performance index of vehicle dynamics exceeds a certain debounce time threshold. The designed control algorithm is implemented on a virtual prototype and cosimulations are performed with different road disturbance inputs. Cosimulation results show that the active hydropneumatic suspension system designed in this study significantly improves riding comfort characteristics of vehicles. The robustness and adaptability of the proposed controller are also examined when the control system is subjected to extremely rough road conditions.

  4. Utility allowed returns and market extremes

    International Nuclear Information System (INIS)

    Murry, D.A.; Nan, G.D.; Harrington, B.M.

    1993-01-01

    In recent years interest rates have fluctuated from exceptionally high levels in the early 1980s to their current levels, the lowest in two decades. Observers and analysts generally have assumed that allowed returns by regulatory commissions follow the movement of interest rates; indeed some analysts use a risk premium method to estimate the cost of common equity, assuming a constant and linear relationship between interest rates and the cost of common equity. That suggests we could expect a relatively stable relationship between interest rates and allowed returns, as well. However, a simple comparison of allowed returns and interest rates shows that this is not the case in recent years. The relationship between market interest rates and the returns allowed by commissions varies and is obviously a great deal more complicated. Empirically, there appears to be only a narrow range where market interest rates significantly affect the allowed returns on common stock set by state commissions, at least for electric and combination utilities. If rates are at historically low levels, allowed returns based largely on market rates will hasten subsequent rate filings, and commissions appear to look beyond the low rate levels. Conversely, it appears that regulators do not let historically high market rates determine allowed returns either. At either high or low interest levels, caution seems to be the policy

  5. Return to sports after shoulder arthroplasty

    Science.gov (United States)

    Johnson, Christine C; Johnson, Daniel J; Liu, Joseph N; Dines, Joshua S; Dines, David M; Gulotta, Lawrence V; Garcia, Grant H

    2016-01-01

    Many patients prioritize the ability to return to sports following shoulder replacement surgeries, including total shoulder arthroplasty (TSA), reverse total shoulder arthroplasty (RTSA), and hemiarthroplasty (HA). While activity levels after hip and knee replacements have been well-established in the literature, studies on this topic in the field of shoulder arthroplasty are relatively limited. A review of the literature regarding athletic activity after shoulder arthroplasty was performed using the PubMed database. All studies relevant to shoulder arthroplasty and return to sport were included. The majority of patients returned to their prior level of activity within six months following TSA, RTSA, and shoulder HA. Noncontact, low demand activities are permitted by most surgeons postoperatively and generally have higher return rates than contact sports or high-demand activities. In some series, patients reported an improvement in their ability to participate in sports following the arthroplasty procedure. The rates of return to sports following TSA (75%-100%) are slightly higher than those reported for HA (67%-76%) and RTSA (75%-85%). Patients undergoing TSA, RTSA, and shoulder HA should be counseled that there is a high probability that they will be able to return to their preoperative activity level within six months postoperatively. TSA has been associated with higher rates of return to sports than RTSA and HA, although this may reflect differences in patient population or surgical indication. PMID:27672564

  6. Simulation and analysis of vertical displacement characteristics of three wheels reverse trike vehicle with PID controller application

    Science.gov (United States)

    Wibowo, Lambang, Lullus; Erick Chandra, N.; Muhayat, Nurul; Jaka S., B.

    2017-08-01

    The purpose of this research is to obtain a mathematical model (Full Vehicle Model) and compare the performance of passive and active suspension systems of a Three-Wheels Reverse Trike vehicle. Vehicle suspension system should able to provide good steering handling and passenger comfort. Vehicle suspension system generally only uses passive suspension components with fix spring and damper coefficients. An active suspension developed from the traditional (passive) suspension design can directly control the actuator force in the suspension system. In this paper, modeling and simulation of passive and active suspension system for a Full Vehicle Model is performed using Simulink-MATLAB software. Ziegler & Nichols tuning method is used to obtain controller parameters of Proportional Integral Derivative (PID) controller. Comparison between passive and active suspension with PID controller is conducted for disturbances input of single bump road surface profile 0.1 meters. The results are the displacement and acceleration of the vehicle body in the vertical direction of active suspension system with PID control is better in providing handling capabilities and comfort for the driver than of passive suspension system. The acceleration of 1,8G with the down time of 2.5 seconds is smaller than the acceleration of 2.5G with down time of 5.5 seconds.

  7. Using vehicle-to-grid technology for frequency regulation and peak-load reduction

    Science.gov (United States)

    White, Corey D.; Zhang, K. Max

    This paper explores the potential financial return for using plug-in hybrid electric vehicles as a grid resource. While there is little financial incentive for individuals when the vehicle-to-grid (V2G) service is used exclusively for peak reduction, there is a significant potential for financial return when the V2G service is used for frequency regulation. We propose that these two uses for V2G technology are not mutually exclusive, and that there could exist a "dual-use" program that utilizes V2G for multiple uses simultaneously. In our proposition, V2G could be used for regulation on a daily basis to ensure profits, and be used for peak reduction on days with high electricity demand and poor ambient air quality in order to reap the greatest environmental benefits. The profits for the individual in this type of dual-use program are close to or even higher than the profits experienced in either of the single-use programs. More importantly, we argue that the external benefits of this type of program are much greater as well. At higher V2G participation rates, our analysis shows that the market for regulation capacity could become saturated by V2G-based regulation providers. At the same time, there is plenty of potential for widespread use of V2G technology, especially if the demand for regulation, reserves, and storage grows as more intermittent renewable resources are being incorporated into the power systems.

  8. Impact of methanol vehicles on ozone air quality

    Science.gov (United States)

    Chang, T. Y.; Rudy, S. J.; Kuntasal, G.; Gorse, R. A.

    A single-cell trajectory model with an updated chemical mechanism has been used to evaluate the impact on ozone air quality of methanol fueled vehicle (MFV) substitution for conventional fueled vehicles (CFV) in 20 urban areas in the U.S. Recent measurement data for non-methane organic compound (NMOC) concentrations and NMOC/NO x ratios for each of the areas was used. The sensitivity of peak 1-h O 3 values to variations in many of the input parameters has been tested. The functional dependence of peak 1-h O 3 on NMOC/NO x, ratios shows that, for many cities, the maximum O 3 levels occur near the median urban-center 6-9 a.m. NMOC/NO x ratios. The results of the photochemical model computations, including several methanol-fuel substitution scenarios, have been used to derive relative reactivities of methanol and formaldehyde. Per-vehicle O 3 reduction potentials for MFV have also been derived. The reduction potentials and calculated percentage O 3 reductions for selected MFV market-penetrations have been used to estimate the impact of any MFV market-penetration or change in MFV emission factors. All substitution scenarios evaluated lead to projections of lower peak 1-h O 3 levels. Even with significant replacement of CFV by MFV, the reduction of urban O 3 levels appears to be modest. However, the reductions may be significant in comparison to other available O 3-reduction options.

  9. Method for modeling driving cycles, fuel use, and emissions for over snow vehicles.

    Science.gov (United States)

    Hu, Jiangchuan; Frey, H Christopher; Sandhu, Gurdas S; Graver, Brandon M; Bishop, Gary A; Schuchmann, Brent G; Ray, John D

    2014-07-15

    As input to a winter use plan, activity, fuel use, and tailpipe exhaust emissions of over snow vehicles (OSV), including five snow coaches and one snowmobile, were measured on a designated route in Yellowstone National Park (YNP). Engine load was quantified in terms of vehicle specific power (VSP), which is a function of speed, acceleration, and road grade. Compared to highway vehicles, VSP for OSVs is more sensitive to rolling resistance and less sensitive to aerodynamic drag. Fuel use rates increased linearly (R2>0.96) with VSP. For gasoline-fueled OSVs, fuel-based emission rates of carbon monoxide (CO) and nitrogen oxides (NOx) typically increased with increasing fuel use rate, with some cases of very high CO emissions. For the diesel OSVs, which had selective catalytic reduction and diesel particulate filters, fuel-based NOx and particulate matter (PM) emission rates were not sensitive to fuel flow rate, and the emission controls were effective. Inter vehicle variability in cycle average fuel use and emissions rates for CO and NOx was substantial. However, there was relatively little inter-cycle variation in cycle average fuel use and emission rates when comparing driving cycles. Recommendations are made regarding how real-world OSV activity, fuel use, and emissions data can be improved.

  10. Chemical sensors are hybrid-input memristors

    Science.gov (United States)

    Sysoev, V. I.; Arkhipov, V. E.; Okotrub, A. V.; Pershin, Y. V.

    2018-04-01

    Memristors are two-terminal electronic devices whose resistance depends on the history of input signal (voltage or current). Here we demonstrate that the chemical gas sensors can be considered as memristors with a generalized (hybrid) input, namely, with the input consisting of the voltage, analyte concentrations and applied temperature. The concept of hybrid-input memristors is demonstrated experimentally using a single-walled carbon nanotubes chemical sensor. It is shown that with respect to the hybrid input, the sensor exhibits some features common with memristors such as the hysteretic input-output characteristics. This different perspective on chemical gas sensors may open new possibilities for smart sensor applications.

  11. 26 CFR 301.6019-1 - Gift tax returns.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Gift tax returns. 301.6019-1 Section 301.6019-1... ADMINISTRATION PROCEDURE AND ADMINISTRATION Information and Returns Returns and Records § 301.6019-1 Gift tax returns. For provisions relating to requirement of gift tax returns, see §§ 25.6019-1 to 25.6019-4...

  12. Contingency Estimation of States for Unmanned Aerial Vehicle using a Spherical Simplex Unscented Filter

    DEFF Research Database (Denmark)

    Hahn, Tobias; Hansen, Søren; Blanke, Mogens

    2012-01-01

    Aiming at survival from contingency situations for unmanned aerial vehicles, a square root spherical simplex unscented Kalman filter is applied for state and parameter estimation and a rough model is used for state prediction when essential measurements are lost. Processing real flight data, rece...... efficient square root implementation of the filter algorithm. A case of loss of GPS signal demonstrates the use of the state estimates to obtain return of the UAV to close to it’s home base where safe recovery is possible....

  13. Stock Returns and Risk: Evidence from Quantile

    Directory of Open Access Journals (Sweden)

    Thomas C. Chiang

    2012-12-01

    Full Text Available This paper employs weighted least squares to examine the risk-return relation by applying high-frequency data from four major stock indexes in the US market and finds some evidence in favor of a positive relation between the mean of the excess returns and expected risk. However, by using quantile regressions, we find that the risk-return relation moves from negative to positive as the returns’ quantile increases. A positive risk-return relation is valid only in the upper quantiles. The evidence also suggests that intraday skewness plays a dominant role in explaining the variations of excess returns.

  14. Return to Golf After Lumbar Fusion.

    Science.gov (United States)

    Shifflett, Grant D; Hellman, Michael D; Louie, Philip K; Mikhail, Christopher; Park, Kevin U; Phillips, Frank M

    Spinal fusion surgery is being increasingly performed, yet few studies have focused on return to recreational sports after lumbar fusion and none have specifically analyzed return to golf. Most golfers successfully return to sport after lumbar fusion surgery. Case series. Level 4. All patients who underwent 1- or 2-level primary lumbar fusion surgery for degenerative pathologies performed by a single surgeon between January 2008 and October 2012 and had at least 1-year follow-up were included. Patients completed a specifically designed golf survey. Surveys were mailed, given during follow-up clinic, or answered during telephone contact. A total of 353 patients met the inclusion and exclusion criteria, with 200 responses (57%) to the questionnaire producing 34 golfers. The average age of golfers was 57 years (range, 32-79 years). In 79% of golfers, preoperative back and/or leg pain significantly affected their ability to play golf. Within 1 year from surgery, 65% of patients returned to practice and 52% returned to course play. Only 29% of patients stated that continued back/leg pain limited their play. Twenty-five patients (77%) were able to play the same amount of golf or more than before fusion surgery. Of those providing handicaps, 12 (80%) reported the same or an improved handicap. More than 50% of golfers return to on-course play within 1 year of lumbar fusion surgery. The majority of golfers can return to preoperative levels in terms of performance (handicap) and frequency of play. This investigation offers insight into when golfers return to sport after lumbar fusion surgery and provides surgeons with information to set realistic expectations postoperatively.

  15. Sensor Fusion Based on an Integrated Neural Network and Probability Density Function (PDF) Dual Kalman Filter for On-Line Estimation of Vehicle Parameters and States.

    Science.gov (United States)

    Vargas-Melendez, Leandro; Boada, Beatriz L; Boada, Maria Jesus L; Gauchia, Antonio; Diaz, Vicente

    2017-04-29

    Vehicles with a high center of gravity (COG), such as light trucks and heavy vehicles, are prone to rollover. This kind of accident causes nearly 33 % of all deaths from passenger vehicle crashes. Nowadays, these vehicles are incorporating roll stability control (RSC) systems to improve their safety. Most of the RSC systems require the vehicle roll angle as a known input variable to predict the lateral load transfer. The vehicle roll angle can be directly measured by a dual antenna global positioning system (GPS), but it is expensive. For this reason, it is important to estimate the vehicle roll angle from sensors installed onboard in current vehicles. On the other hand, the knowledge of the vehicle's parameters values is essential to obtain an accurate vehicle response. Some of vehicle parameters cannot be easily obtained and they can vary over time. In this paper, an algorithm for the simultaneous on-line estimation of vehicle's roll angle and parameters is proposed. This algorithm uses a probability density function (PDF)-based truncation method in combination with a dual Kalman filter (DKF), to guarantee that both vehicle's states and parameters are within bounds that have a physical meaning, using the information obtained from sensors mounted on vehicles. Experimental results show the effectiveness of the proposed algorithm.

  16. A Simple Analytic Model for Estimating Mars Ascent Vehicle Mass and Performance

    Science.gov (United States)

    Woolley, Ryan C.

    2014-01-01

    The Mars Ascent Vehicle (MAV) is a crucial component in any sample return campaign. In this paper we present a universal model for a two-stage MAV along with the analytic equations and simple parametric relationships necessary to quickly estimate MAV mass and performance. Ascent trajectories can be modeled as two-burn transfers from the surface with appropriate loss estimations for finite burns, steering, and drag. Minimizing lift-off mass is achieved by balancing optimized staging and an optimized path-to-orbit. This model allows designers to quickly find optimized solutions and to see the effects of design choices.

  17. Development of Constraint Force Equation Methodology for Application to Multi-Body Dynamics Including Launch Vehicle Stage Seperation

    Science.gov (United States)

    Pamadi, Bandu N.; Toniolo, Matthew D.; Tartabini, Paul V.; Roithmayr, Carlos M.; Albertson, Cindy W.; Karlgaard, Christopher D.

    2016-01-01

    The objective of this report is to develop and implement a physics based method for analysis and simulation of multi-body dynamics including launch vehicle stage separation. The constraint force equation (CFE) methodology discussed in this report provides such a framework for modeling constraint forces and moments acting at joints when the vehicles are still connected. Several stand-alone test cases involving various types of joints were developed to validate the CFE methodology. The results were compared with ADAMS(Registered Trademark) and Autolev, two different industry standard benchmark codes for multi-body dynamic analysis and simulations. However, these two codes are not designed for aerospace flight trajectory simulations. After this validation exercise, the CFE algorithm was implemented in Program to Optimize Simulated Trajectories II (POST2) to provide a capability to simulate end-to-end trajectories of launch vehicles including stage separation. The POST2/CFE methodology was applied to the STS-1 Space Shuttle solid rocket booster (SRB) separation and Hyper-X Research Vehicle (HXRV) separation from the Pegasus booster as a further test and validation for its application to launch vehicle stage separation problems. Finally, to demonstrate end-to-end simulation capability, POST2/CFE was applied to the ascent, orbit insertion, and booster return of a reusable two-stage-to-orbit (TSTO) vehicle concept. With these validation exercises, POST2/CFE software can be used for performing conceptual level end-to-end simulations, including launch vehicle stage separation, for problems similar to those discussed in this report.

  18. Study on the Vehicle Dynamic Load Considering the Vehicle-Pavement Coupled Effect

    Science.gov (United States)

    Xu, H. L.; He, L.; An, D.

    2017-11-01

    The vibration of vehicle-pavement interaction system is sophisticated random vibration process and the vehicle-pavement coupled effect was not considered in the previous study. A new linear elastic model of the vehicle-pavement coupled system was established in the paper. The new model was verified with field measurement which could reflect the real vibration between vehicle and pavement. Using the new model, the study on the vehicle dynamic load considering the vehicle-pavement coupled effect showed that random forces (centralization) between vehicle and pavement were influenced largely by vehicle-pavement coupled effect. Numerical calculation indicated that the maximum of random forces in coupled model was 2.4 times than that in uncoupled model. Inquiring the reason, it was found that the main vibration frequency of the vehicle non-suspension system was similar with that of the vehicle suspension system in the coupled model and the resonance vibration lead to vehicle dynamic load increase significantly.

  19. Establishing bonds between vehicle certification data and real-world vehicle fuel consumption – A Vehicle Specific Power approach

    International Nuclear Information System (INIS)

    Duarte, G.O.; Gonçalves, G.A.; Baptista, P.C.; Farias, T.L.

    2015-01-01

    Highlights: • Innovative methodology to estimate VSP fuel consumption based on public available data. • Model validation with accurate fuel consumption results (absolute deviation from 4.7% to 9.2%). • Best-selling vehicles in Portugal case study was developed for different driving cycles. - Abstract: A method to perform the energy characterization of a vehicle according to the specific power required while driving was developed using public vehicle certification data. Using a portable emission measurement system, fuel consumption was quantified in a second-by-second basis under on-road conditions for 19 vehicles (spark-ignition, compression-ignition and hybrids). This data allowed building generic curves of fuel consumption as a function of the specific power, according to Vehicle Specific Power methodology. Comparing on-road measurements and the model estimates, a R 2 higher than 0.9 for conventional and hybrid vehicles was obtained regarding modal fuel consumption. Comparing the fuel consumption measured on the drive cycles performed by each vehicle and the correspondent estimates, an absolute deviation of 9.2% ± 9.2% was found for conventional vehicles and 4.7% ± 1.8% for hybrids vehicles. This methodology was validated and applied to estimate the energy impacts of the best-selling vehicles in Portugal for different driving cycles. This prompt method, that does not require vehicle monitoring, can estimate curves of fuel consumption in g/s, as a function of specific power, which allows quantifying the absolute fuel use for any driving cycle

  20. Dynamic surface tracking controller design for a constrained hypersonic vehicle based on disturbance observer

    Directory of Open Access Journals (Sweden)

    Fang Wang

    2017-05-01

    Full Text Available The tracking control problem of a flexible air-breathing hypersonic vehicle subjects to aerodynamic parameter uncertainty and input constraint is investigated by combining nonlinear disturbance observer and dynamic surface control. To design controller simply, a control-oriented model is firstly derived and divided into two subsystems, velocity subsystem and altitude subsystem based on the engineering backgrounds of flexible air-breathing hypersonic vehicle. In every subsystem, compounded disturbances are included to consider aerodynamic uncertainty and the effect of the flexible modes. Then, disturbance observer is not only used to handle the compounded disturbance but also to handle the input constraint, where the estimation error converges to a random small region through appropriately choosing the observer parameters. To sequel, the disturbance observer–based robust control scheme and the disturbance observer-based dynamic surface control scheme are developed for the velocity subsystem and altitude subsystem, respectively. Besides, novel filters are designed to alleviate the problem of “explosion of terms” induced by backstepping method. On the basis of Lyapunov stability theory, the presented control scheme can assure that tracking error converges to an arbitrarily small neighborhood around zero by rigorous theoretical analysis. At last, simulation result shows the effectiveness of the presented control method.

  1. Does Aggregated Returns Disclosure Increase Portfolio Risk Taking?

    Science.gov (United States)

    Beshears, John; Choi, James J; Laibson, David; Madrian, Brigitte C

    2017-06-01

    Many experiments have found that participants take more investment risk if they see returns less frequently, see portfolio-level returns (rather than each individual asset's returns), or see long-horizon (rather than one-year) historical return distributions. In contrast, we find that such information aggregation treatments do not affect total equity investment when we make the investment environment more realistic than in prior experiments. Previously documented aggregation effects are not robust to changes in the risky asset's return distribution or the introduction of a multi-day delay between portfolio choice and return realizations.

  2. Appreciate the Appreciation: Imported Inputs and Concern Over Dutch Disease

    Directory of Open Access Journals (Sweden)

    Wardah Naim

    2013-03-01

    worrying about Dutch Disease and, rather, welcome a higher Canadian dollar. But more than that, they should design policies that are better tailored for an economy that relies so heavily on imported intermediate inputs. Policy efforts would be far better put to eliminating tariffs and other trade barriers that make imported inputs more expensive, and thus hamper Canadian competitiveness. Policies should also focus on improving productivity, by inviting foreign investment, rather than subtly discouraging it through vehicles such as the Investment Canada Act. And certainly, anything that forces businesses to “buy local,” as Ontario’s Green Energy Act requires, will only stand in the way of Canadian businesses taking advantage of our higher dollar by importing lower-cost inputs from abroad. If policy-makers want to help Canadian factories, they shouldn’t complain about Alberta but instead focus on improving their domestic economic policies instead.

  3. Penerapan Konsep Vehicle Routing Problem dalam Kasus Pengangkutan Sampah di Perkotaan

    Directory of Open Access Journals (Sweden)

    Harun Al Rasyid Lubis

    2016-12-01

    Full Text Available Cities in developing countries still operate a traditional waste transport and handling where rubbish were collected at regular intervals by specialized trucks from curb-side collection or transfer point prior to transport them to a final dump site. The problem are worsening as some cities experience exhausted waste collection services because the system is inadequately managed, fiscal capacity to invest in adequate vehicle fleets is lacking and also due to uncontrolled dumpsites location. In this paper problem of waste collection and handling is formulated based on Capacitated Vehicle Routing Problem Time Window Multiple Depo Intermediete Facility (CVRPTWMDIF. Each vehicle was assigned to visit several intermediate transfer points, until the truck loading or volume capacity reached then waste are transported to final landfill or dump site. Finally all trucks will return to a depot at the end of daily operation. Initially the solution of CVRPTWMDIF problem was tested on a simple hypothetical waste handling before being implemented into a real case problem. Solutions found using CVRPTWMDIF compared with the practice of waste transport and handling in the city of Bandung. Based on a common hours of operation and the same number of transport fleets, it was found that CVRPTWMDIF can reduce the volume of waste that is not transported by almost half by the end of the daily operations.

  4. Online forecasting of electrical load for distributed management of plug-in electric vehicles

    OpenAIRE

    Basu , Kaustav; Ovalle , Andres; Guo , Baoling; Hably , Ahmad; Bacha , Seddik; Hajar , Khaled

    2016-01-01

    International audience; The paper aims at making online forecast of electrical load at the MV-LV transformer level. Optimal management of the Plug-in Electric Vehicles (PEV) charging requires the forecast of the electrical load for future hours. The forecasting module needs to be online (i.e update and make forecast for the future hours, every hour). The inputs to the predictor are historical electrical and weather data. Various data driven machine learning algorithms are compared to derive t...

  5. An efficient recursive least square-based condition monitoring approach for a rail vehicle suspension system

    Science.gov (United States)

    Liu, X. Y.; Alfi, S.; Bruni, S.

    2016-06-01

    A model-based condition monitoring strategy for the railway vehicle suspension is proposed in this paper. This approach is based on recursive least square (RLS) algorithm focusing on the deterministic 'input-output' model. RLS has Kalman filtering feature and is able to identify the unknown parameters from a noisy dynamic system by memorising the correlation properties of variables. The identification of suspension parameter is achieved by machine learning of the relationship between excitation and response in a vehicle dynamic system. A fault detection method for the vertical primary suspension is illustrated as an instance of this condition monitoring scheme. Simulation results from the rail vehicle dynamics software 'ADTreS' are utilised as 'virtual measurements' considering a trailer car of Italian ETR500 high-speed train. The field test data from an E464 locomotive are also employed to validate the feasibility of this strategy for the real application. Results of the parameter identification performed indicate that estimated suspension parameters are consistent or approximate with the reference values. These results provide the supporting evidence that this fault diagnosis technique is capable of paving the way for the future vehicle condition monitoring system.

  6. Weight and cost forecasting for advanced manned space vehicles

    Science.gov (United States)

    Williams, Raymond

    1989-01-01

    A mass and cost estimating computerized methology for predicting advanced manned space vehicle weights and costs was developed. The user friendly methology designated MERCER (Mass Estimating Relationship/Cost Estimating Relationship) organizes the predictive process according to major vehicle subsystem levels. Design, development, test, evaluation, and flight hardware cost forecasting is treated by the study. This methodology consists of a complete set of mass estimating relationships (MERs) which serve as the control components for the model and cost estimating relationships (CERs) which use MER output as input. To develop this model, numerous MER and CER studies were surveyed and modified where required. Additionally, relationships were regressed from raw data to accommodate the methology. The models and formulations which estimated the cost of historical vehicles to within 20 percent of the actual cost were selected. The result of the research, along with components of the MERCER Program, are reported. On the basis of the analysis, the following conclusions were established: (1) The cost of a spacecraft is best estimated by summing the cost of individual subsystems; (2) No one cost equation can be used for forecasting the cost of all spacecraft; (3) Spacecraft cost is highly correlated with its mass; (4) No study surveyed contained sufficient formulations to autonomously forecast the cost and weight of the entire advanced manned vehicle spacecraft program; (5) No user friendly program was found that linked MERs with CERs to produce spacecraft cost; and (6) The group accumulation weight estimation method (summing the estimated weights of the various subsystems) proved to be a useful method for finding total weight and cost of a spacecraft.

  7. Economics- and policy-driven organic carbon input enhancement dominates soil organic carbon accumulation in Chinese croplands.

    Science.gov (United States)

    Zhao, Yongcun; Wang, Meiyan; Hu, Shuijin; Zhang, Xudong; Ouyang, Zhu; Zhang, Ganlin; Huang, Biao; Zhao, Shiwei; Wu, Jinshui; Xie, Deti; Zhu, Bo; Yu, Dongsheng; Pan, Xianzhang; Xu, Shengxiang; Shi, Xuezheng

    2018-04-17

    China's croplands have experienced drastic changes in management practices, such as fertilization, tillage, and residue treatments, since the 1980s. There is an ongoing debate about the impact of these changes on soil organic carbon (SOC) and its implications. Here we report results from an extensive study that provided direct evidence of cropland SOC sequestration in China. Based on the soil sampling locations recorded by the Second National Soil Survey of China in 1980, we collected 4,060 soil samples in 2011 from 58 counties that represent the typical cropping systems across China. Our results showed that across the country, the average SOC stock in the topsoil (0-20 cm) increased from 28.6 Mg C ha -1 in 1980 to 32.9 Mg C ha -1 in 2011, representing a net increase of 140 kg C ha -1 year -1 However, the SOC change differed among the major agricultural regions: SOC increased in all major agronomic regions except in Northeast China. The SOC sequestration was largely attributed to increased organic inputs driven by economics and policy: while higher root biomass resulting from enhanced crop productivity by chemical fertilizers predominated before 2000, higher residue inputs following the large-scale implementation of crop straw/stover return policy took over thereafter. The SOC change was negatively related to N inputs in East China, suggesting that the excessive N inputs, plus the shallowness of plow layers, may constrain the future C sequestration in Chinese croplands. Our results indicate that cropland SOC sequestration can be achieved through effectively manipulating economic and policy incentives to farmers.

  8. Enhanced Input in LCTL Pedagogy

    Directory of Open Access Journals (Sweden)

    Marilyn S. Manley

    2009-08-01

    Full Text Available Language materials for the more-commonly-taught languages (MCTLs often include visual input enhancement (Sharwood Smith 1991, 1993 which makes use of typographical cues like bolding and underlining to enhance the saliency of targeted forms. For a variety of reasons, this paper argues that the use of enhanced input, both visual and oral, is especially important as a tool for the lesscommonly-taught languages (LCTLs. As there continues to be a scarcity of teaching resources for the LCTLs, individual teachers must take it upon themselves to incorporate enhanced input into their own self-made materials. Specific examples of how to incorporate both visual and oral enhanced input into language teaching are drawn from the author’s own experiences teaching Cuzco Quechua. Additionally, survey results are presented from the author’s Fall 2010 semester Cuzco Quechua language students, supporting the use of both visual and oral enhanced input.

  9. Enhanced Input in LCTL Pedagogy

    Directory of Open Access Journals (Sweden)

    Marilyn S. Manley

    2010-08-01

    Full Text Available Language materials for the more-commonly-taught languages (MCTLs often include visual input enhancement (Sharwood Smith 1991, 1993 which makes use of typographical cues like bolding and underlining to enhance the saliency of targeted forms. For a variety of reasons, this paper argues that the use of enhanced input, both visual and oral, is especially important as a tool for the lesscommonly-taught languages (LCTLs. As there continues to be a scarcity of teaching resources for the LCTLs, individual teachers must take it upon themselves to incorporate enhanced input into their own self-made materials. Specific examples of how to incorporate both visual and oral enhanced input into language teaching are drawn from the author’s own experiences teaching Cuzco Quechua. Additionally, survey results are presented from the author’s Fall 2010 semester Cuzco Quechua language students, supporting the use of both visual and oral enhanced input.

  10. Vehicle State Estimator based regenerative braking implementation on an electric vehicle to improve lateral vehicle stability

    NARCIS (Netherlands)

    Jansen, S.T.H.; van Boekel, J.J.P.; Iersel, van S.S.; Besselink, I.J.M.; Nijmeijer, H.

    2013-01-01

    The driving range of electric vehicles can be extended using regenerative braking. Regenerative braking uses the electric drive system, and therefore only the driven wheels, for decelerating the vehicle. Braking on one axle affects the stability of the vehicle, especially for road conditions with

  11. Vehicle state estimator based regenerative braking implementation on an electric vehicle to improve lateral vehicle stability

    NARCIS (Netherlands)

    Jansen, S.T.H.; Boekel, J.J.P. van; Iersel, S.S. van; Besselink, I.J.M.; Nijmeijer, H.

    2013-01-01

    The driving range of electric vehicles can be extended using regenerative braking. Regenerative braking uses the elctric drive system, and therefore only the driven wheels, for decelerating the vehicle. Braking on one axle affects the stability of the vehicle, especially for road conditions with

  12. 41 CFR 102-34.85 - What motor vehicles require motor vehicle identification?

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What motor vehicles require motor vehicle identification? 102-34.85 Section 102-34.85 Public Contracts and Property Management... 34-MOTOR VEHICLE MANAGEMENT Identifying and Registering Motor Vehicles Motor Vehicle Identification...

  13. Vehicle to Vehicle Services

    DEFF Research Database (Denmark)

    Brønsted, Jeppe Rørbæk

    2008-01-01

    location aware infotainment, increase safety, and lessen environmental strain. This dissertation is about service oriented architecture for pervasive computing with an emphasis on vehicle to vehicle applications. If devices are exposed as services, applications can be created by composing a set of services...... be evaluated. Service composition mechanisms for pervasive computing are categorized and we discuss how the characteristics of pervasive computing can be supported by service composition mechanisms. Finally, we investigate how to make pervasive computing systems capable of being noticed and understood...

  14. Vehicle barrier systems

    International Nuclear Information System (INIS)

    Sena, P.A.

    1986-01-01

    The ground vehicle is one of the most effective tools available to an adversary force. Vehicles can be used to penetrate many types of perimeter barriers, transport equipment and personnel rapidly over long distances, and deliver large amounts of explosives directly to facilities in suicide missions. The function of a vehicle barrier system is to detain or disable a defined threat vehicle at a selected distance from a protected facility. Numerous facilities are installing, or planning to install, vehicle barrier systems and many of these facilities are requesting guidance to do so adequately. Therefore, vehicle barriers are being evaluated to determine their stopping capabilities so that systems can be designed that are both balanced and capable of providing a desired degree of protection. Equally important, many of the considerations that should be taken into account when establishing a vehicle barrier system have been identified. These considerations which pertain to site preparation, barrier selection, system integration and operation, and vehicle/barrier interaction, are discussed in this paper

  15. Does Aggregated Returns Disclosure Increase Portfolio Risk Taking?

    Science.gov (United States)

    Beshears, John; Choi, James J.; Laibson, David; Madrian, Brigitte C.

    2016-01-01

    Many experiments have found that participants take more investment risk if they see returns less frequently, see portfolio-level returns (rather than each individual asset’s returns), or see long-horizon (rather than one-year) historical return distributions. In contrast, we find that such information aggregation treatments do not affect total equity investment when we make the investment environment more realistic than in prior experiments. Previously documented aggregation effects are not robust to changes in the risky asset’s return distribution or the introduction of a multi-day delay between portfolio choice and return realizations. PMID:28553012

  16. Connected vehicle applications : safety.

    Science.gov (United States)

    2016-01-01

    Connected vehicle safety applications are designed to increase situational awareness : and reduce or eliminate crashes through vehicle-to-infrastructure, vehicle-to-vehicle, : and vehicle-to-pedestrian data transmissions. Applications support advisor...

  17. Measurement of returns-to-scale using Interval Data Envelopment Analysis models

    DEFF Research Database (Denmark)

    Hatami-Marbini, Adel; Beigi, Zahra Ghelej; Hougaard, Jens Leth

    2018-01-01

    The economic concept of Returns-to-Scale (RTS) has been intensively studied in the context of Data Envelopment Analysis (DEA). The conventional DEA models that are used for RTS classification require well-defined and accurate data whereas in reality observations gathered from production systems may...... be characterized by intervals. For instance, the heat losses of the combined production of heat and power (CHP) systems may be within a certain range, hinging on a wide variety of factors such as external temperature and real-time energy demand. Enriching the current literature independently tackling the two...... problems; interval data and RTS estimation; we develop an overarching evaluation process for estimating RTS of Decision Making Units (DMUs) in Imprecise DEA (IDEA) where the input and output data lie within bounded intervals. In the presence of interval data, we introduce six types of RTS involving...

  18. Near Space Hypersonic Unmanned Aerial Vehicle Dynamic Surface Backstepping Control Design

    Directory of Open Access Journals (Sweden)

    Jinyong YU

    2014-07-01

    Full Text Available Compared with traditional aircraft, the near space hypersonic unmanned aerial vehicle control system design must deal with the extra prominent dynamics characters, which are differ from the traditional aircrafts control system design. A new robust adaptive control design method is proposed for one hypersonic unmanned aerial vehicle (HSUAV uncertain MIMO nonaffine block control system by using multilayer neural networks, feedback linearization technology, and dynamic surface backstepping. Multilayer neural networks are used to compensate the influence from the uncertain, which designs the robust terms to solve the problem from approach error. Adaptive backstepping is adopted designed to ensure control law, the dynamic surface control strategy to eliminate “the explosion of terms” by introducing a series of first order filters to obtain the differentiation of the virtual control inputs. Finally, nonlinear six-degree-of-freedom (6-DOF numerical simulation results for a HSUAV model are presented to demonstrate the effectiveness of the proposed method.

  19. MDS MIC Catalog Inputs

    Science.gov (United States)

    Johnson-Throop, Kathy A.; Vowell, C. W.; Smith, Byron; Darcy, Jeannette

    2006-01-01

    This viewgraph presentation reviews the inputs to the MDS Medical Information Communique (MIC) catalog. The purpose of the group is to provide input for updating the MDS MIC Catalog and to request that MMOP assign Action Item to other working groups and FSs to support the MITWG Process for developing MIC-DDs.

  20. Vehicle following controller design for autonomous intelligent vehicles

    Science.gov (United States)

    Chien, C. C.; Lai, M. C.; Mayr, R.

    1994-01-01

    A new vehicle following controller is proposed for autonomous intelligent vehicles. The proposed vehicle following controller not only provides smooth transient maneuvers for unavoidable nonzero initial conditions but also guarantees the asymptotic platoon stability without the availability of feedforward information. Furthermore, the achieved asymptotic platoon stability is shown to be robust to sensor delays and an upper bound for the allowable sensor delays is also provided in this paper.

  1. Light vehicle crash avoidance needs and countermeasure profiles for safety applications based on vehicle-to-vehicle communications

    Science.gov (United States)

    2013-04-30

    This report discusses light-vehicle crash countermeasure profiles and functions for five target pre-crash scenario groups based on vehicle-to-vehicle (V2V) communications. Target pre-crash scenario groups include rear-end, lane change, opposite direc...

  2. Are there Diminishing Returns to R&D?

    DEFF Research Database (Denmark)

    Madsen, Jakob B.

    Semi-endogenous models and, to some extent, also Schumpeterian models are based on the assumption of diminishing returns to R&D. This paper shows that the null hypothesis of constant returns to R&D cannot be rejected for the OECD countries......Semi-endogenous models and, to some extent, also Schumpeterian models are based on the assumption of diminishing returns to R&D. This paper shows that the null hypothesis of constant returns to R&D cannot be rejected for the OECD countries...

  3. Performance Characteristics of a Modularized and Integrated PTC Heating System for an Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Yoon Hyuk Shin

    2015-12-01

    Full Text Available A modularized positive temperature coefficient heating system has controller-integrated heater modules. Such a heating system that uses a high-voltage power of 330 V was developed in the present study for use in electric vehicles. Four heater modules and one controller with an input power of 5.6 kW were integrated in the modularized system, which was designed for improved heating power density and light weight compared to the conventional heating system, in which the controller is separated. We experimentally investigated the performance characteristics, namely, the heating capacity, energy efficiency, and pressure drop, of a prototype of the developed heating system and found it to have satisfactory performance. The findings of this study will contribute to the development of heating systems for electric vehicles.

  4. A Lateral Control Method of Intelligent Vehicle Based on Fuzzy Neural Network

    Directory of Open Access Journals (Sweden)

    Linhui Li

    2015-01-01

    Full Text Available A lateral control method is proposed for intelligent vehicle to track the desired trajectory. Firstly, a lateral control model is established based on the visual preview and dynamic characteristics of intelligent vehicle. Then, the lateral error and orientation error are melded into an integrated error. Considering the system parameter perturbation and the external interference, a sliding model control is introduced in this paper. In order to design a sliding surface, the integrated error is chosen as the parameter of the sliding mode switching function. The sliding mode switching function and its derivative are selected as two inputs of the controller, and the front wheel angle is selected as the output. Next, a fuzzy neural network is established, and the self-learning functions of neural network is utilized to construct the fuzzy rules. Finally, the simulation results demonstrate the effectiveness and robustness of the proposed method.

  5. State-of-the-art assessment of electric vehicles and hybrid vehicles

    Science.gov (United States)

    1977-01-01

    The Electric and Hybrid Vehicle Research, Development, and Demonstration Act of 1976 (PL 94-413) requires that data be developed to characterize the state of the art of vehicles powered by an electric motor and those propelled by a combination of an electric motor and an internal combustion engine or other power sources. Data obtained from controlled tests of a representative number of sample vehicles, from information supplied by manufacturers or contained in the literature, and from surveys of fleet operators of individual owners of electric vehicles is discussed. The results of track and dynamometer tests conducted by NASA on 22 electric, 2 hybrid, and 5 conventional vehicles, as well as on 5 spark-ignition-engine-powered vehicles, the conventional counterparts of 5 of the vehicles, are presented.

  6. Employing Multiple Unmanned Aerial Vehicles for Co-Operative Path Planning

    Directory of Open Access Journals (Sweden)

    Durdana Habib

    2013-05-01

    Full Text Available Abstract In this paper, we work to develop a path planning solution for a group of Unmanned Aerial Vehicles (UAVs using a Mixed Integer Linear Programming (MILP approach. Co-operation among team members not only helps reduce mission time, it makes the execution more robust in dynamic environments. However, the problem becomes more challenging as it requires optimal resource allocation and is NP-hard. Since UAVs may be lost or may suffer significant damage during the course of the mission, plans may need to be modified in real-time as the mission proceeds. Therefore, multiple UAVs have a better chance of completing a mission in the face of failures. Such military operations can be treated as a variant of the Multiple Depot Vehicle Routing Problem (MDVRP. The proposed solution must be such that m UAVs start from multiple source locations to visit n targets and return to a set of destination locations such that (1 each target is visited exactly by one of the chosen UAVs (2 the total distance travelled by the group is minimized and (3 the number of targets that each UAV visits may not be less than K or greater than L.

  7. Adaptive fuzzy tracking control for a constrained flexible air-breathing hypersonic vehicle based on actuator compensation

    Directory of Open Access Journals (Sweden)

    Peng Fei Wang

    2016-10-01

    Full Text Available The design of an adaptive fuzzy tracking control for a flexible air-breathing hypersonic vehicle with actuator constraints is discussed. Based on functional decomposition methodology, velocity and altitude controllers are designed. Fuzzy logic systems are applied to approximate the lumped uncertainty of each subsystem of air-breathing hypersonic vehicle model. Every controllers contain only one adaptive parameter that needs to be updated online with a minimal-learning-parameter scheme. The back-stepping design is not demanded by converting the altitude subsystem into the normal output-feedback formulation, which predigests the design of a controller. The special contribution is that novel auxiliary systems are developed to compensate both the tracking errors and desired control laws, based on which the explored controller can still provide effective tracking of velocity and altitude commands when the inputs are saturated. Finally, reference trajectory tracking simulation shows the effectiveness of the proposed method in its application to air-breathing hypersonic vehicle control.

  8. Connected vehicle application : safety.

    Science.gov (United States)

    2015-01-01

    Connected vehicle safety applications are designed to increase situational awareness : and reduce or eliminate crashes through vehicle-to-infrastructure (V2I), vehicle-to-vehicle (V2V), and vehicle-to-pedestrian (V2P) data transmissions. Applications...

  9. Pipeline monitoring with unmanned aerial vehicles

    Science.gov (United States)

    Kochetkova, L. I.

    2018-05-01

    Pipeline leakage during transportation of combustible substances leads to explosion and fire thus causing death of people and destruction of production and accommodation facilities. Continuous pipeline monitoring allows identifying leaks in due time and quickly taking measures for their elimination. The paper describes the solution of identification of pipeline leakage using unmanned aerial vehicles. It is recommended to apply the spectral analysis with input RGB signal to identify pipeline damages. The application of multi-zone digital images allows defining potential spill of oil hydrocarbons as well as possible soil pollution. The method of multi-temporal digital images within the visible region makes it possible to define changes in soil morphology for its subsequent analysis. The given solution is cost efficient and reliable thus allowing reducing timing and labor resources in comparison with other methods of pipeline monitoring.

  10. Design and modelling of high gain DC-DC converters for fuel cell hybrid electric vehicles

    Science.gov (United States)

    Elangovan, D.; Karthigeyan, V.; Subhanu, B.; Ashwin, M.; Arunkumar, G.

    2017-11-01

    Transportation (Diesel and petrol internal combustion engine vehicles) approximately contributes to 25.5% of total CO2 emission. Thus diesel and petrol engine vehicles are the most dominant contributors of CO2 emission which leads global warming which causes climate change. The problem of CO2 emission and global warming can be reduced by focusing on renewable energy vehicles. Out of the available renewable energy sources fuel cell is the only source which has reasonable efficiency and can be used in vehicles. But the main disadvantage of fuel cell is its slow response time. So energy storage systems like batteries and super capacitors are used in parallel with the fuel cell. Fuel cell is used during steady state vehicle operation while during transient conditions like starting, acceleration and braking batteries and super capacitors can supply or absorb energy. In this paper a unidirectional fuel cell DC-DC converter and bidirectional energy storage system DC-DC converter is proposed, which can interface dc sources at different voltage levels to the dc bus and also it can independently control the power flow from each energy source to the dc bus and vice versa. The proposed converters are designed and simulated using PSIM version 9.1.1 and gate pulse pattern, input and output voltage waveforms of the converters for steady state operation are studied.

  11. Regime switches in the risk-return trade-off

    OpenAIRE

    Marcellino, Massimiliano; Ghysels, Eric; Guerin, Pierre

    2014-01-01

    This paper deals with the estimation of the risk-return trade-off. We use a MIDAS model for the conditional variance and allow for possible switches in the risk-return relation through a Markov-switching specification. We find strong evidence for regime changes in the risk-return relation. This finding is robust to a large range of specifications. In the first regime characterized by low ex-post returns and high volatility, the risk-return relation is reversed, whereas the intuitive positive ...

  12. ANALYSING TURKISH INDIVIDUAL PENSION SYSTEM FEES AND RETURNS

    OpenAIRE

    Peker, Ibrahim

    2018-01-01

    This study aims at categorizing, computing and analyzing fees and costs in Turkish Individual Pension System. To this end, net real returns after all costs were computed and these returns were compared with the disclosed fees and returns. Generally in practice, only fund management fees are taken into consideration for calculating net returns and with this method net annual average (geometric) return of the system is calculated as 2.01% for the 2008-2014 period. However, the results of this s...

  13. Input-output energy analysis in dry apricot production of Turkey

    International Nuclear Information System (INIS)

    Esengun, Kemal; Guenduez, Orhan; Erdal, Guelistan

    2007-01-01

    The aims of this study were to determine the amount of input-output energy used in dry apricot production, to investigate the efficiency of energy consumption and to make an economic analysis of dry apricot production in Malatya, Turkey. Data used in this study were obtained from 97 farmers using a face to face questionnaire method. The sample farms were selected through a stratified random sampling technique. The population investigated was divided into two strata based on the size of apricot farms as 0.1-3.0 ha (66 farms) and larger than 3.1 ha (31 farms). The results revealed that 28647.03 MJ ha -1 energy were consumed by the first group and 17884.72 MJ ha -1 by the second group of farmers. The input-output ratio and productivities were 1.24 and 0.24 in the first strata and 1.31 and 0.25 in the second strata, respectively. Results further indicated that in both types of farms, 3/4 of the total energy cost was in non-renewable energy forms, and only 1/4 was in renewable forms. The economic analyses showed that the profit-cost ratios of the farms were 1.11 and 1.19, respectively. Net returns calculated were 414.51 $ ha -1 and 495.59 $ ha -1 in the farms investigated. It was concluded that extension activities are needed to improve the efficiency of energy consumption in dry apricot production and to employ environmentally friendly agricultural management practices and production methods

  14. Vehicle to grid: electric vehicles as an energy storage solution

    Science.gov (United States)

    McGee, Rodney; Waite, Nicholas; Wells, Nicole; Kiamilev, Fouad E.; Kempton, Willett M.

    2013-05-01

    With increased focus on intermittent renewable energy sources such as wind turbines and photovoltaics, there comes a rising need for large-scale energy storage. The vehicle to grid (V2G) project seeks to meet this need using electric vehicles, whose high power capacity and existing power electronics make them a promising energy storage solution. This paper will describe a charging system designed by the V2G team that facilitates selective charging and backfeeding by electric vehicles. The system consists of a custom circuit board attached to an embedded linux computer that is installed both in the EVSE (electric vehicle supply equipment) and in the power electronics unit of the vehicle. The boards establish an in-band communication link between the EVSE and the vehicle, giving the vehicle internet connectivity and the ability to make intelligent decisions about when to charge and discharge. This is done while maintaining compliance with existing charging protocols (SAEJ1772, IEC62196) and compatibility with standard "nonintelligent" cars and chargers. Through this system, the vehicles in a test fleet have been able to successfully serve as portable temporary grid storage, which has implications for regulating the electrical grid, providing emergency power, or supplying power to forward military bases.

  15. RFID-based vehicle positioning and its applications in connected vehicles.

    Science.gov (United States)

    Wang, Jianqiang; Ni, Daiheng; Li, Keqiang

    2014-03-04

    This paper proposed an RFID-based vehicle positioning approach to facilitate connected vehicles applications. When a vehicle passes over an RFID tag, the vehicle position is given by the accurate position stored in the tag. At locations without RFID coverage, the vehicle position is estimated from the most recent tag location using a kinematics integration algorithm till updates from the next tag. The accuracy of RFID positioning is verified empirically in two independent ways with one using radar and the other a photoelectric switch. The former is designed to verify whether the dynamic position obtained from RFID tags matches the position measured by radar that is regarded as accurate. The latter aims to verify whether the position estimated from the kinematics integration matches the position obtained from RFID tags. Both means supports the accuracy of RFID-based positioning. As a supplement to GPS which suffers from issues such as inaccuracy and loss of signal, RFID positioning is promising in facilitating connected vehicles applications. Two conceptual applications are provided here with one in vehicle operational control and the other in Level IV intersection control.

  16. Do expectancies of return to work and Job satisfaction predict actual return to work in workers with long lasting LBP?

    Science.gov (United States)

    Opsahl, Jon; Eriksen, Hege R; Tveito, Torill H

    2016-11-17

    Musculoskeletal disorders including low back pain have major individual and socioeconomic consequences as it often leads to disability and long-term sick leave and exclusion from working life. Predictors of disability and return to work often differ, and the dominant knowledge is on predictors for prolonged sick leave and disability. Therefore it is also important to identify key predictors for return to work. The aim of the study was to assess if overall job satisfaction and expectancies of return to work predicts actual return to work after 12 months, among employees with long lasting low back pain, and to assess if there were gender differences in the predictors. Data from the Cognitive interventions and nutritional supplements trial (CINS Trial) was used. Predictors for return to work were examined in 574 employees that had been on sick leave 2-10 months for low back pain, before entering the trial. Data were analysed with multiple logistic regression models stratified by gender, and adjusted for potential confounders. Regardless of gender high expectancies were a strong and significant predictor of return to work at 12 months, while high levels of job satisfaction were not a significant predictor. There were no differences in the levels of expectancies or overall job satisfaction between men and women. However, men had in general higher odds of returning to work compared with women. Among individuals with long lasting low back pain high expectancies of returning to work were strongly associated with successful return to work. We do not know what factors influence individual expectancies of return to work. Screening expectancies and giving individuals with low expectancies interventions with a goal to change expectancies of return to work, such as CBT or self-management interventions, may contribute to increase actual return to work. http://www.clinicaltrials.gov/ , with registration number NCT00463970 . The trial was registered at the 18th of April 2007.

  17. KINERJA KEUANGAN KONVENSIONAL, ECONOMIC VALUE ADDED, DAN RETURN SAHAM

    Directory of Open Access Journals (Sweden)

    Bambang Sudiyatno

    2011-09-01

    Full Text Available Penelitian ini bertujuan untuk menguji pengaruh kinerja keuangan konvensional; Return on Asset (ROA, Return on Equity (ROE, Residual Income (RI, dan kinerja keuangan yang lebih modern; Economic Value Added (EVA terhadap return saham pada perusahaan-perusahaan dalam industry makanan dan minuman yang terdaftar di Bursa Efek Indonesia. Pengambilan sampel dalam penelitian ini menggunakan metode sensus, karena semua perusahaan dalam industry makanan dan minuman digunakan sebagai sampel. Namun dalam proses samplingnya mengunakan metode purposive sampling, yaitu menggunakan sampel dengan criteria-kriteria tertentu. Hasil penelitian menunjukkan bahwa Return on Asset (ROA dan Residual Income (RI berpengaruh positif dan secara statistik signifikan terhadap return saham pada level signifikansi 1%. Sedangkan Return on Equity (ROE berpengaruh negative dan secara statistik signifikan terhadap return saham pada level signifikansi 10%, dan Economic Value Added (ERA berpengaruh positif tetapi tidak signifikan terhadap return saham.This study aims to test the effect of conventional financial performance i.e. Return on Asset (ROA, Return on Equity (ROE, Residual Income (RI, and the more modern financial performance which is Economic Value Added (EVA toward stock returns on companies in the food and beverage industry listed in Indonesia Stock Exchange. Sampling technique in this study uses the census method, all companies in the food and beverage industry are used as a sample. The process of sampling using purposive sampling method. The result shows that Return On Asset (ROA and Residual Income (RI are positive and statistic significant impact on the stock returns at significance level 1%. While the Return on Equity (ROE is negative and statistic significant impact on the stock returns at significance level 10%, Economic Value Added (EVA is positive and statistic not significant impact on the stock returns.

  18. The Determinants of Return Migration: Evidence for Kosovo

    Directory of Open Access Journals (Sweden)

    Ardiana Gashi

    2015-12-01

    Full Text Available Return migration represents a potentially important contributor to economic development for countries that are large exporters of labor. This paper provides an analysis of the determinants of return migration to Kosovo, a country with an especially high level of recent emigration. The findings of this investigation suggest that there is a non-linear relationship between the age of the migrant and their probability of returning. In addition, the more educated migrants and those that have acquired additional education whilst abroad are more likely to return, whereas recent migrants, those that possess permanent resident status and have their family abroad are less likely to return. As expected, the stronger the family ties of a migrant with their home country, the more likely they are to return. Finally, migrants that are expected to invest in businesses in Kosovo are more inclined to return. Together these findings suggest that return migration may be an important contributor to economic development in Kosovo and policies are outlined that could strengthen this contribution.

  19. Return Migration among Elderly, Chronically Ill Bosnian Refugees

    DEFF Research Database (Denmark)

    Handlos, Line Neerup; Olwig, Karen Fog; Bygbjerg, Ib Christian

    2015-01-01

    Elderly migrants constitute a considerable share of global return migration; nevertheless, literature on the health aspects of the return migration among these migrants is still scarce. This study explores the significance of return migration among elderly, chronically ill Bosnian refugees from D...... of illness, health did matter. Viewed as physical, social and mental well-being in line with WHO's definition of health, health was indeed one of the most important factors when the decision to return was made....... that physical health, in the sense of the absence of illness and easy access to necessary health-care services and medicines, was not highly prioritized when the decision was made whether or not to return. However, if health is regarded more broadly as involving more than mere physical health and the absence......Elderly migrants constitute a considerable share of global return migration; nevertheless, literature on the health aspects of the return migration among these migrants is still scarce. This study explores the significance of return migration among elderly, chronically ill Bosnian refugees from...

  20. Broadband vehicle-to-vehicle communication using an extended autonomous cruise control sensor

    Science.gov (United States)

    Heddebaut, M.; Rioult, J.; Ghys, J. P.; Gransart, Ch; Ambellouis, S.

    2005-06-01

    For several years road vehicle autonomous cruise control (ACC) systems as well as anti-collision radar have been developed. Several manufacturers currently sell this equipment. The current generation of ACC sensors only track the first preceding vehicle to deduce its speed and position. These data are then used to compute, manage and optimize a safety distance between vehicles, thus providing some assistance to car drivers. However, in real conditions, to elaborate and update a real time driving solution, car drivers use information about speed and position of preceding and following vehicles. This information is essentially perceived using the driver's eyes, binocular stereoscopic vision performed through the windscreens and rear-view mirrors. Furthermore, within a line of vehicles, the frontal road perception of the first vehicle is very particular and highly significant. Currently, all these available data remain strictly on-board the vehicle that has captured the perception information and performed these measurements. To get the maximum effectiveness of all these approaches, we propose that this information be shared in real time with the following vehicles, within the convoy. On the basis of these considerations, this paper technically explores a cost-effective solution to extend the basic ACC sensor function in order to simultaneously provide a vehicle-to-vehicle radio link. This millimetre wave radio link transmits relevant broadband perception data (video, localization...) to following vehicles, along the line of vehicles. The propagation path between the vehicles uses essentially grazing angles of incidence of signals over the road surface including millimetre wave paths beneath the cars.

  1. Input filter compensation for switching regulators

    Science.gov (United States)

    Lee, F. C.; Kelkar, S. S.

    1982-01-01

    The problems caused by the interaction between the input filter, output filter, and the control loop are discussed. The input filter design is made more complicated because of the need to avoid performance degradation and also stay within the weight and loss limitations. Conventional input filter design techniques are then dicussed. The concept of pole zero cancellation is reviewed; this concept is the basis for an approach to control the peaking of the output impedance of the input filter and thus mitigate some of the problems caused by the input filter. The proposed approach for control of the peaking of the output impedance of the input filter is to use a feedforward loop working in conjunction with feedback loops, thus forming a total state control scheme. The design of the feedforward loop for a buck regulator is described. A possible implementation of the feedforward loop design is suggested.

  2. Corporate Governance and Equity Returns

    OpenAIRE

    Uchida, Shigeru

    2012-01-01

    This paper analyses the relationship between corporate governance and equity returns from the small investors view point. A primary survey has been conducted to gather the data required to examine the link. Preliminary result of the study shows that the four elements of governance: board structure, transparency, fairness and responsibility are positively related with equity returns.

  3. Effectiveness of Securities with Fuzzy Probabilistic Return

    Directory of Open Access Journals (Sweden)

    Krzysztof Piasecki

    2011-01-01

    Full Text Available The generalized fuzzy present value of a security is defined here as fuzzy valued utility of cash flow. The generalized fuzzy present value cannot depend on the value of future cash flow. There exists such a generalized fuzzy present value which is not a fuzzy present value in the sense given by some authors. If the present value is a fuzzy number and the future value is a random one, then the return rate is given as a probabilistic fuzzy subset on a real line. This kind of return rate is called a fuzzy probabilistic return. The main goal of this paper is to derive the family of effective securities with fuzzy probabilistic return. Achieving this goal requires the study of the basic parameters characterizing fuzzy probabilistic return. Therefore, fuzzy expected value and variance are determined for this case of return. These results are a starting point for constructing a three-dimensional image. The set of effective securities is introduced as the Pareto optimal set determined by the maximization of the expected return rate and minimization of the variance. Finally, the set of effective securities is distinguished as a fuzzy set. These results are obtained without the assumption that the distribution of future values is Gaussian. (original abstract

  4. 22 CFR 42.22 - Returning resident aliens.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at the...

  5. Vehicle Integrated Photovoltaics for Compression Ignition Vehicles: An Experimental Investigation of Solar Alkaline Water Electrolysis for Improving Diesel Combustion and a Solar Charging System for Reducing Auxiliary Engine Loads

    Science.gov (United States)

    Negroni, Garry Inocentes

    Vehicle-integrated photovoltaic electricity can be applied towards aspiration of hydrogen-oxygen-steam gas produced through alkaline electrolysis and reductions in auxiliary alternator load for reducing hydrocarbon emissions in low nitrogen oxide indirect-injection compression-ignition engines. Aspiration of 0.516 ± 0.007 liters-per-minute of gas produced through alkaline electrolysis of potassium-hydroxide 2wt.% improves full-load performance; however, part-load performance decreases due to auto-ignition of aspirated gas prior to top-dead center. Alternator load reductions offer improved part-load and full-load performance with practical limitations resulting from accessory electrical loads. In an additive approach, solar electrolysis can electrochemically convert solar photovoltaic electricity into a gas comprised of stoichiometric hydrogen and oxygen gas. Aspiration of this hydrogen-oxygen gas enhances combustion properties decreasing emissions and increased combustion efficiency in light-duty diesel vehicles. The 316L stainless steel (SS) electrolyser plates are arranged with two anodes and three cathodes space with four bipolar plates delineating four stacks in parallel with five cells per stack. The electrolyser was tested using potassium hydroxide 2 wt.% and hydronium 3wt.% at measured voltage and current inputs. The flow rate output from the reservoir cell was measured in parallel with the V and I inputs producing a regression model correlating current input to flow rate. KOH 2 wt.% produced 0.005 LPM/W, while H9O44 3 wt.% produced less at 0.00126 LPM/W. In a subtractive approach, solar energy can be used to charge a larger energy storage device, as is with plug-in electric vehicles, in order to alleviate the engine of the mechanical load placed upon it by the vehicles electrical accessories through the alternator. Solar electrolysis can improve part-load emissions and full-load performance. The average solar-to-battery efficiency based on the OEM rated

  6. Volatility return intervals analysis of the Japanese market

    Science.gov (United States)

    Jung, W.-S.; Wang, F. Z.; Havlin, S.; Kaizoji, T.; Moon, H.-T.; Stanley, H. E.

    2008-03-01

    We investigate scaling and memory effects in return intervals between price volatilities above a certain threshold q for the Japanese stock market using daily and intraday data sets. We find that the distribution of return intervals can be approximated by a scaling function that depends only on the ratio between the return interval τ and its mean . We also find memory effects such that a large (or small) return interval follows a large (or small) interval by investigating the conditional distribution and mean return interval. The results are similar to previous studies of other markets and indicate that similar statistical features appear in different financial markets. We also compare our results between the period before and after the big crash at the end of 1989. We find that scaling and memory effects of the return intervals show similar features although the statistical properties of the returns are different.

  7. A computer code to design liquid containers for vehicles

    International Nuclear Information System (INIS)

    Parizi, H.B.; Fard, M.P.; Dolatabadi, A.

    2003-01-01

    We are presenting the development of a modular code for the simulation of the fluid sloshing that occurs in the liquid containers in vehicles. Sloshing occurs when a partially filled container of liquid goes through transient or steady external forces. Under such conditions, the free surface of the liquid may move and the liquid may impact on the walls of the container, exchanging forces. These forces may cause numerous harmful and undesirable consequences in the operation of the vehicle, such as vehicle turn over. The fluid mechanic equations that describe the fluid sloshing in the container and the dynamic equations that describe the movement of the container are solved separately in two different codes. The codes are coupled weekly, such that the output of one code will be used as the input to the other code in the same time step. The outputs of the fluid code are the forces and torques that are applied to the body of the container due to sloshing, whereas the output of the dynamic code are the translational and rotational velocities and accelerations of the container. The proposed software can be used to test the performance of the designed container under various operating condition and allow effective improvements to the container design. The proposed code is different than the presently available codes, in that it will provide a true simulation of the coupled fluid and structure interaction. (author)

  8. Aggregated GPS tracking of vehicles and its use as a proxy of traffic-related air pollution emissions

    Science.gov (United States)

    Chen, Shimon; Bekhor, Shlomo; Yuval; Broday, David M.

    2016-10-01

    Most air quality models use traffic-related variables as an input. Previous studies estimated nearby vehicular activity through sporadic traffic counts or via traffic assignment models. Both methods have previously produced poor or no data for nights, weekends and holidays. Emerging technologies allow the estimation of traffic through passive monitoring of location-aware devices. Examples of such devices are GPS transceivers installed in vehicles. In this work, we studied traffic volumes that were derived from such data. Additionally, we used these data for estimating ambient nitrogen dioxide concentrations, using a non-linear optimisation model that includes basic dispersion properties. The GPS-derived data show great potential for use as a proxy for pollutant emissions from motor-vehicles.

  9. Vehicle underbody fairing

    Science.gov (United States)

    Ortega, Jason M.; Salari, Kambiz; McCallen, Rose

    2010-11-09

    A vehicle underbody fairing apparatus for reducing aerodynamic drag caused by a vehicle wheel assembly, by reducing the size of a recirculation zone formed under the vehicle body immediately downstream of the vehicle wheel assembly. The fairing body has a tapered aerodynamic surface that extends from a front end to a rear end of the fairing body with a substantially U-shaped cross-section that tapers in both height and width. Fasteners or other mounting devices secure the fairing body to an underside surface of the vehicle body, so that the front end is immediately downstream of the vehicle wheel assembly and a bottom section of the tapered aerodynamic surface rises towards the underside surface as it extends in a downstream direction.

  10. Position and force control of a vehicle with two or more steerable drive wheels

    Energy Technology Data Exchange (ETDEWEB)

    Reister, D.B.; Unseren, M.A.

    1992-10-01

    When a vehicle with two or more steerable drive wheels is traveling in a circle, the motion of the wheels is constrained. The wheel translational velocity divided by the radius to the center of rotation must be the same for all wheels. When the drive wheels are controlled independently using position control, the motion of the wheels may violate the constraints and the wheels may slip. Consequently, substantial errors can occur in the orientation of the vehicle. A vehicle with N drive wheels has (N - 1) constraints and one degree of freedom. We have developed a new approach to the control of a vehicle with N steerable drive wheels. The novel aspect of our approach is the use of force control. To control the vehicle, we have one degree of freedom for the position on the circle and (N - 1) forces that can be used to reduce errors. Recently, Kankaanranta and Koivo developed a control architecture that allows the force and position degrees of freedom to be decoupled. In the work of Kankaanranta and Koivo the force is an exogenous input. We have made the force endogenous by defining the force in terms of the errors in satisfying the rigid body kinematic constraints. We have applied the control architecture to the HERMIES-III robot and have measured a dramatic reduction in error (more than a factor of 20) compared to motions without force control.

  11. Return currents in solar flares - Collisionless effects

    Science.gov (United States)

    Rowland, H. L.; Vlahos, L.

    1985-01-01

    If the primary, precipitating electrons in a solar flare are unstable to beam plasma interactions, it is shown that strong Langmuir turbulence can seriously modify the way in which a return current is carried by the background plasma. In particular, the return (or reverse) current will not be carried by the bulk of the electrons, but by a small number of high velocity electrons. For beam/plasma densities greater than 0.01, this can reduce the effects of collisions on the return current. For higher density beams where the return current could be unstable to current driven instabilities, the effects of strong turbulence anomalous resistivity is shown to prevent the appearance of such instabilities. Again in this regime, how the return current is carried is determined by the beam generated strong turbulence.

  12. Value at Risk and Hedge Fund Return - Does High Risk Bring High Return?

    OpenAIRE

    Jing, Tao; Zhao, Hongxiang

    2010-01-01

    This paper mainly focuses on the correlation between live hedge fund return and their value at risk (VaR), and is based on the historical data from May 2000 to April 2010. The authors adopt portfolio level analyses and fund level cross-sectional regression, and find that there is significant positive correlation, both statistically and economically, between the hedge fund return and VaRs (parametric, non-parametric and GARCH). Further research is conducted by sub-dividing the overall period i...

  13. Vehicle technologies, fuel-economy policies, and fuel-consumption rates of Chinese vehicles

    International Nuclear Information System (INIS)

    Huo Hong; He Kebin; Wang, Michael; Yao Zhiliang

    2012-01-01

    One of the principal ways to reduce transport-related energy use is to reduce fuel-consumption rates of motor vehicles (usually measured in liters of fuel per 100 km). Since 2004, China has implemented policies to improve vehicle technologies and lower the fuel-consumption rates of individual vehicles. Policy evaluation requires accurate and adequate information on vehicle fuel-consumption rates. However, such information, especially for Chinese vehicles under real-world operating conditions, is rarely available from official sources in China. For each vehicle type we first review the vehicle technologies and fuel-economy policies currently in place in China and their impacts. We then derive real-world (or on-road) fuel-consumption rates on the basis of information collected from various sources. We estimate that the real-world fuel-consumption rates of vehicles in China sold in 2009 are 9 L/100 km for light-duty passenger vehicles, 11.4 L/100 km for light-duty trucks, 22 L/100 km for inter-city transport buses, 40 L/100 km for urban transit buses, and 24.9 L/100 km for heavy-duty trucks. These results aid in understanding the levels of fuel consumption of existing Chinese vehicle fleets and the effectiveness of policies in reducing on-road fuel consumption, which can help in designing and evaluating future vehicle energy-efficiency policies. - Highlights: ► Vehicle fuel-consumption rate (VFCR) data are rarely available in China. ► We review the fuel-economy policies currently in place in China and their impacts. ► We derive real-world VFCRs on the basis of information collected from various sources. ► Results aid in understanding the fuel consumption levels of Chinese vehicle fleets. ► Results help in designing and evaluating future vehicle energy-efficiency policies.

  14. Linkage between company scores and stock returns

    Directory of Open Access Journals (Sweden)

    Saban Celik

    2017-12-01

    Full Text Available Previous studies on company scores conducted at firm-level, generally concluded that there exists a positive relation between company scores and stock returns. Motivated by these studies, this study examines the relationship between company scores (Corporate Governance Score, Economic Score, Environmental Score, and Social Score and stock returns, both at portfolio-level analysis and firm-level cross-sectional regressions. In portfolio-level analysis, stocks are sorted based on each company scores and quintile portfolio are formed with different levels of company scores. Then, existence and significance of raw returns and risk-adjusted returns difference between portfolios with the extreme company scores (portfolio 10 and portfolio 1 is tested. In addition, firm-level cross-sectional regression is performed to examine the significance of company scores effects with control variables. While portfolio-level analysis results indicate that there is no significant relation between company scores and stock returns; firm-level analysis indicates that economic, environmental, and social scores have effect on stock returns, however, significance and direction of these effects change, depending on the included control variables in the cross-sectional regression.

  15. Consensus seeking, formation keeping, and trajectory tracking in multiple vehicle cooperative control

    Science.gov (United States)

    Ren, Wei

    stringent inter-vehicle communication limitations. A constructive approach based on the satisficing control paradigm is also applied to multi-robot coordination in hardware. For trajectory tracking, we investigate nonlinear tracking controllers for fixed wing unmanned air vehicles and nonholonomic mobile robots with velocity and heading rate constraints. The main contribution of this dissertation in this area is that our proposed tracking controllers are shown to be robust to input uncertainties and measurement noise, and are computationally simple and can be implemented with low-cost, low-power microcontrollers. In addition, our approach allows piecewise continuous reference velocity and heading rate and can be extended to derive a variety of other trajectory tracking strategies.

  16. 7 CFR 3430.607 - Stakeholder input.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Stakeholder input. 3430.607 Section 3430.607 Agriculture Regulations of the Department of Agriculture (Continued) COOPERATIVE STATE RESEARCH, EDUCATION... § 3430.607 Stakeholder input. CSREES shall seek and obtain stakeholder input through a variety of forums...

  17. Inactive nurses in Taiwan: human capital, intention to return to hospital nursing, and incentives for returning.

    Science.gov (United States)

    Yu, Hsing-Yi; Tang, Fu-In; Chen, I-Ju; Yin, Teresa J C; Chen, Chu-Chieh; Yu, Shu

    2016-04-01

    To investigate inactive nurses' human capital, intention to return to hospital nursing and incentives for returning. Few studies have discussed the loss of human capital with regard to inactive nurses and how to attract them to return to clinical work. Systematic random sampling was used, with 328 subjects completing the mailed questionnaires, resulting in a response rate of 25.4%. Inactive nurses not only had moderate to high human capital (average years of nursing experience was 10.29, with moderate to high levels of nursing professional commitment and nursing competence) and were young. Forty-three percent of subjects reported intending to return to hospital nursing. Sufficient nurse staffing, greater safety in the working environment, and re-entry preparation programmes were incentives for returning. Recruiting inactive nurses back to hospital work is vital and feasible as inactive nurses had a moderate to high degree of human capital. The most feasible way is offering reasonable working conditions, in particular, providing sufficient staffing, a safe working environment and re-entry preparation programmes. The findings confirm the human capital of inactive nurses and provide concrete directions for nursing managers to follow when recruiting inactive nurses to hospital nursing. © 2015 John Wiley & Sons Ltd.

  18. Stencil cutouts for virtual reality inputs

    CSIR Research Space (South Africa)

    Ausmeier, Natalie J

    2017-02-01

    Full Text Available Virtual Reality (VR) is widely used in training simulators of dangerous or expensive vehicles such as aircraft or heavy mining machinery. The vehicles often have very complicated controls that users need to master before attempting to operate a real...

  19. The Profile Envision and Splicing Tool (PRESTO): Developing an Atmospheric Wind Analysis Tool for Space Launch Vehicles Using Python

    Science.gov (United States)

    Orcutt, John M.; Barbre, Robert E., Jr.; Brenton, James C.; Decker, Ryan K.

    2017-01-01

    Launch vehicle programs require vertically complete atmospheric profiles. Many systems at the ER to make the necessary measurements, but all have different EVR, vertical coverage, and temporal coverage. MSFC Natural Environments Branch developed a tool to create a vertically complete profile from multiple inputs using Python. Forward work: Finish Formal Testing Acceptance Testing, End-to-End Testing. Formal Release

  20. RFID-Based Vehicle Positioning and Its Applications in Connected Vehicles

    Science.gov (United States)

    Wang, Jianqiang; Ni, Daiheng; Li, Keqiang

    2014-01-01

    This paper proposed an RFID-based vehicle positioning approach to facilitate connected vehicles applications. When a vehicle passes over an RFID tag, the vehicle position is given by the accurate position stored in the tag. At locations without RFID coverage, the vehicle position is estimated from the most recent tag location using a kinematics integration algorithm till updates from the next tag. The accuracy of RFID positioning is verified empirically in two independent ways with one using radar and the other a photoelectric switch. The former is designed to verify whether the dynamic position obtained from RFID tags matches the position measured by radar that is regarded as accurate. The latter aims to verify whether the position estimated from the kinematics integration matches the position obtained from RFID tags. Both means supports the accuracy of RFID-based positioning. As a supplement to GPS which suffers from issues such as inaccuracy and loss of signal, RFID positioning is promising in facilitating connected vehicles applications. Two conceptual applications are provided here with one in vehicle operational control and the other in Level IV intersection control. PMID:24599188

  1. RFID-Based Vehicle Positioning and Its Applications in Connected Vehicles

    Directory of Open Access Journals (Sweden)

    Jianqiang Wang

    2014-03-01

    Full Text Available This paper proposed an RFID-based vehicle positioning approach to facilitate connected vehicles applications. When a vehicle passes over an RFID tag, the vehicle position is given by the accurate position stored in the tag. At locations without RFID coverage, the vehicle position is estimated from the most recent tag location using a kinematics integration algorithm till updates from the next tag. The accuracy of RFID positioning is verified empirically in two independent ways with one using radar and the other a photoelectric switch. The former is designed to verify whether the dynamic position obtained from RFID tags matches the position measured by radar that is regarded as accurate. The latter aims to verify whether the position estimated from the kinematics integration matches the position obtained from RFID tags. Both means supports the accuracy of RFID-based positioning. As a supplement to GPS which suffers from issues such as inaccuracy and loss of signal, RFID positioning is promising in facilitating connected vehicles applications. Two conceptual applications are provided here with one in vehicle operational control and the other in Level IV intersection control.

  2. Space vehicle chassis

    Science.gov (United States)

    Judd, Stephen; Dallmann, Nicholas; Seitz, Daniel; Martinez, John; Storms, Steven; Kestell, Gayle

    2017-07-18

    A modular space vehicle chassis may facilitate convenient access to internal components of the space vehicle. Each module may be removable from the others such that each module may be worked on individually. Multiple panels of at least one of the modules may swing open or otherwise be removable, exposing large portions of the internal components of the space vehicle. Such chassis architectures may reduce the time required for and difficulty of performing maintenance or modifications, may allow multiple space vehicles to take advantage of a common chassis design, and may further allow for highly customizable space vehicles.

  3. World Input-Output Network.

    Directory of Open Access Journals (Sweden)

    Federica Cerina

    Full Text Available Production systems, traditionally analyzed as almost independent national systems, are increasingly connected on a global scale. Only recently becoming available, the World Input-Output Database (WIOD is one of the first efforts to construct the global multi-regional input-output (GMRIO tables. By viewing the world input-output system as an interdependent network where the nodes are the individual industries in different economies and the edges are the monetary goods flows between industries, we analyze respectively the global, regional, and local network properties of the so-called world input-output network (WION and document its evolution over time. At global level, we find that the industries are highly but asymmetrically connected, which implies that micro shocks can lead to macro fluctuations. At regional level, we find that the world production is still operated nationally or at most regionally as the communities detected are either individual economies or geographically well defined regions. Finally, at local level, for each industry we compare the network-based measures with the traditional methods of backward linkages. We find that the network-based measures such as PageRank centrality and community coreness measure can give valuable insights into identifying the key industries.

  4. 7 CFR 3430.15 - Stakeholder input.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Stakeholder input. 3430.15 Section 3430.15... Stakeholder input. Section 103(c)(2) of the Agricultural Research, Extension, and Education Reform Act of 1998... RFAs for competitive programs. CSREES will provide instructions for submission of stakeholder input in...

  5. Comparative analysis of the operation efficiency of the continuous and relay control systems of a multi-axle wheeled vehicle suspension

    Science.gov (United States)

    Zhileykin, M. M.; Kotiev, G. O.; Nagatsev, M. V.

    2018-02-01

    In order to improve the efficiency of the multi-axle wheeled vehicles (MWV) automotive engineers are increasing their cruising speed. One of the promising ways to improve ride comfort of the MWV is the development of the dynamic active suspension systems and control laws for such systems. Here, by the dynamic control systems we mean the systems operating in real time mode and using current (instantaneous) values of the state variables. The aim of the work is to develop the MWV suspension optimal control laws that would reduce vibrations on the driver’s seat at kinematic excitation. The authors have developed the optimal control laws for damping the oscillations of the MWV body. The developed laws allow reduction of the vibrations on the driver’s seat and increase in the maximum speed of the vehicle. The laws are characterized in that they allow generating the control inputs in real time mode. The authors have demonstrated the efficiency of the proposed control laws by means of mathematical simulation of the MWV driving over unpaved road with kinematic excitation. The proposed optimal control laws can be used in the MWV suspension control systems with magnetorheological shock absorbers or controlled hydropneumatic springs. Further evolution of the research line can be the development of the energy-efficient MWV suspension control systems with continuous control input on the vehicle body.

  6. Exploring Longitudinal Risk-return Relationships

    DEFF Research Database (Denmark)

    Andersen, Torben J.; Bettis, Richard A.

    2015-01-01

    We study a longitudinal fit model of adaptation and its association with the longitudinal risk-return relationship. The model allows the firm to adjust its position in response to partial learning about a changing environment characterized by two path-dependent processes—a random walk and a stoch......We study a longitudinal fit model of adaptation and its association with the longitudinal risk-return relationship. The model allows the firm to adjust its position in response to partial learning about a changing environment characterized by two path-dependent processes—a random walk...... can lead to the inverse longitudinal risk-return relationships observed empirically. We discuss this apparent paradox and the possible resolution between mindless and conscious behavior as plausible causes of the longitudinal Bowman Paradox....

  7. Integrated Vehicle Thermal Management - Combining Fluid Loops in Electric Drive Vehicles (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Rugh, J. P.

    2013-07-01

    Plug-in hybrid electric vehicles and electric vehicles have increased vehicle thermal management complexity, using separate coolant loop for advanced power electronics and electric motors. Additional thermal components result in higher costs. Multiple cooling loops lead to reduced range due to increased weight. Energy is required to meet thermal requirements. This presentation for the 2013 Annual Merit Review discusses integrated vehicle thermal management by combining fluid loops in electric drive vehicles.

  8. Driving While Interacting With Google Glass: Investigating the Combined Effect of Head-Up Display and Hands-Free Input on Driving Safety and Multitask Performance.

    Science.gov (United States)

    Tippey, Kathryn G; Sivaraj, Elayaraj; Ferris, Thomas K

    2017-06-01

    This study evaluated the individual and combined effects of voice (vs. manual) input and head-up (vs. head-down) display in a driving and device interaction task. Advances in wearable technology offer new possibilities for in-vehicle interaction but also present new challenges for managing driver attention and regulating device usage in vehicles. This research investigated how driving performance is affected by interface characteristics of devices used for concurrent secondary tasks. A positive impact on driving performance was expected when devices included voice-to-text functionality (reducing demand for visual and manual resources) and a head-up display (HUD) (supporting greater visibility of the driving environment). Driver behavior and performance was compared in a texting-while-driving task set during a driving simulation. The texting task was completed with and without voice-to-text using a smartphone and with voice-to-text using Google Glass's HUD. Driving task performance degraded with the addition of the secondary texting task. However, voice-to-text input supported relatively better performance in both driving and texting tasks compared to using manual entry. HUD functionality further improved driving performance compared to conditions using a smartphone and often was not significantly worse than performance without the texting task. This study suggests that despite the performance costs of texting-while-driving, voice input methods improve performance over manual entry, and head-up displays may further extend those performance benefits. This study can inform designers and potential users of wearable technologies as well as policymakers tasked with regulating the use of these technologies while driving.

  9. Input description for BIOPATH

    International Nuclear Information System (INIS)

    Marklund, J.E.; Bergstroem, U.; Edlund, O.

    1980-01-01

    The computer program BIOPATH describes the flow of radioactivity within a given ecosystem after a postulated release of radioactive material and the resulting dose for specified population groups. The present report accounts for the input data necessary to run BIOPATH. The report also contains descriptions of possible control cards and an input example as well as a short summary of the basic theory.(author)

  10. The Reference Return Ratio

    DEFF Research Database (Denmark)

    Nicolaisen, Jeppe; Faber Frandsen, Tove

    2008-01-01

    The paper introduces a new journal impact measure called The Reference Return Ratio (3R). Unlike the traditional Journal Impact Factor (JIF), which is based on calculations of publications and citations, the new measure is based on calculations of bibliographic investments (references) and returns...... (citations). A comparative study of the two measures shows a strong relationship between the 3R and the JIF. Yet, the 3R appears to correct for citation habits, citation dynamics, and composition of document types - problems that typically are raised against the JIF. In addition, contrary to traditional...

  11. Return to nucleate boiling

    International Nuclear Information System (INIS)

    Shumway, R.W.

    1985-01-01

    This paper presents a collection of TMIN (temperature of return to nucleate boiling) correlations, evaluates them under several conditions, and compares them with a wide range of data. Purpose is to obtain the best one for use in a water reactor safety computer simulator known as TRAC-B. Return to nucleate boiling can occur in a reactor accident at either high or low pressure and flow rates. Most of the correlations yield unrealistic results under some conditions. A new correlation is proposed which overcomes many of the deficiencies

  12. ModSAF-based development of operational requirements for light armored vehicles

    Science.gov (United States)

    Rapanotti, John; Palmarini, Marc

    2003-09-01

    Light Armoured Vehicles (LAVs) are being developed to meet the modern requirements of rapid deployment and operations other than war. To achieve these requirements, passive armour is minimized and survivability depends more on sensors, computers, countermeasures and communications to detect and avoid threats. The performance, reliability, and ultimately the cost of these systems, will be determined by the technology trends and the rates at which they mature. Defining vehicle requirements will depend upon an accurate assessment of these trends over a longer term than was previously needed. Modelling and simulation are being developed to study these long-term trends and how they contribute to establishing vehicle requirements. ModSAF is being developed for research and development, in addition to the original requirement of Simulation and Modelling for Acquisition, Rehearsal, Requirements and Training (SMARRT), and is becoming useful as a means for transferring technology to other users, researchers and contractors. This procedure eliminates the need to construct ad hoc models and databases. The integration of various technologies into a Defensive Aids Suite (DAS) can be designed and analyzed by combining field trials and laboratory data with modelling and simulation. ModSAF (Modular Semi-Automated Forces,) is used to construct the virtual battlefield and, through scripted input files, a "fixed battle" approach is used to define and implement contributions from three different sources. These contributions include: models of technology and natural phenomena from scientists and engineers, tactics and doctrine from the military and detailed analyses from operations research. This approach ensures the modelling of processes known to be important regardless of the level of information available about the system. Survivability of DAS-equipped vehicles based on future and foreign technology can be investigated by ModSAF and assessed relative to a test vehicle. A vehicle can

  13. Hypersonic drone vehicle design: A multidisciplinary experience

    Science.gov (United States)

    1988-01-01

    UCLA's Advanced Aeronautic Design group focussed their efforts on design problems of an unmanned hypersonic vehicle. It is felt that a scaled hypersonic drone is necesary to bridge the gap between present theory on hypersonics and the future reality of the National Aerospace Plane (NASP) for two reasons: (1) to fulfill a need for experimental data in the hypersonic regime, and (2) to provide a testbed for the scramjet engine which is to be the primary mode of propulsion for the NASP. The group concentrated on three areas of great concern to NASP design: propulsion, thermal management, and flight systems. Problem solving in these areas was directed toward design of the drone with the idea that the same design techniques could be applied to the NASP. A 70 deg swept double-delta wing configuration, developed in the 70's at the NASA Langley, was chosen as the aerodynamic and geometric model for the drone. This vehicle would be air launched from a B-1 at Mach 0.8 and 48,000 feet, rocket boosted by two internal engines to Mach 10 and 100,000 feet, and allowed to cruise under power of the scramjet engine until burnout. It would then return to base for an unpowered landing. Preliminary energy calculations based on flight requirements give the drone a gross launch weight of 134,000 pounds and an overall length of 85 feet.

  14. Vehicle Dynamic Prediction Systems with On-Line Identification of Vehicle Parameters and Road Conditions

    Science.gov (United States)

    Hsu, Ling-Yuan; Chen, Tsung-Lin

    2012-01-01

    This paper presents a vehicle dynamics prediction system, which consists of a sensor fusion system and a vehicle parameter identification system. This sensor fusion system can obtain the six degree-of-freedom vehicle dynamics and two road angles without using a vehicle model. The vehicle parameter identification system uses the vehicle dynamics from the sensor fusion system to identify ten vehicle parameters in real time, including vehicle mass, moment of inertial, and road friction coefficients. With above two systems, the future vehicle dynamics is predicted by using a vehicle dynamics model, obtained from the parameter identification system, to propagate with time the current vehicle state values, obtained from the sensor fusion system. Comparing with most existing literatures in this field, the proposed approach improves the prediction accuracy both by incorporating more vehicle dynamics to the prediction system and by on-line identification to minimize the vehicle modeling errors. Simulation results show that the proposed method successfully predicts the vehicle dynamics in a left-hand turn event and a rollover event. The prediction inaccuracy is 0.51% in a left-hand turn event and 27.3% in a rollover event. PMID:23202231

  15. Different forms, reasons and motivations for return migration of persons who voluntarily decide to return to their countries of origin.

    Science.gov (United States)

    Callea, S

    1986-03-01

    Although the 1973 oil crisis did not have the drastic effects on immigration which were originally feared, it did end a period of quasi-liberal immigration policy, establish intense and effective international cooperation on immigration, and arouse great interest in immigration studies and research. This paper analyzes the situations arising as a result of the petroleum shortage and focuses on the conditions relating to the return of emigrants to Southern European countries. This new research draws attention to the following fundamental aspects of the immigration problem: 1) the emigrant's return to his homeland cannot be considered a factor in development; it is a positive element in development only if the right socioeconomic conditions exist in the country of origin. 2) Concern for children's education is one of the most common reasons for return. 3) A large percentage of emigrants are satisfied with their work abroad. 4) An emigrant's return potential is wasted due to the slight use that is made of the resources he offers. 5) Returning workers most often want to set up an independent enterprise. 6) Savings are generally used to buy a house or farm. 7) Vocational level does not increase significantly between emigration and returning, though this increase becomes greater the longer the emigrant stays abroad. 8) The number of returning emigrants is too slight to bring about any change in the country of origin. 9) Incentives and subsidies to encourage return have not had a considerable impact on the decision to return. Callea recommends that officials of the country of origin posted abroad be assigned to counsel returning emigrants on finding employment, attending vocational development courses, obtaining housing, accruing interests and savings, and on the problems and perspectives of sociocultural reintegration.

  16. 2017 DOE Vehicle Technologies Office Annual Merit Review

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-10-31

    The 2017 U.S. Department of Energy (DOE) Hydrogen and Fuel Cells Program and Vehicle Technologies Office (VTO) Annual Merit Review and Peer Evaluation Meeting (AMR) was held June 5-9, 2017, in Washington, DC. The review encompassed work done by the Hydrogen and Fuel Cells Program and VTO: 263 individual activities were reviewed for VTO by 191 reviewers. Exactly 1,241 individual review responses were received for the VTO technical reviews. The objective of the meeting was to review the accomplishments and plans for VTO over the previous 12 months, and provide an opportunity for industry, government, and academia to give inputs to DOE with a structured and formal methodology. The meeting also provided attendees with a forum for interaction and technology information transfer.

  17. 2016 DOE Vehicle Technologies Office Annual Merit Review

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2016-12-01

    The 2016 U.S. Department of Energy (DOE) Hydrogen and Fuel Cells Program and Vehicle Technologies Office (VTO) Annual Merit Review and Peer Evaluation Meeting (AMR) was held June 6-9, 2016, in Washington, DC. The review encompassed work done by the Hydrogen and Fuel Cells Program and VTO: 226 individual activities were reviewed for VTO, by 171 reviewers. A total of 1,044 individual review responses were received for the VTO technical reviews. The objective of the meeting was to review the accomplishments and plans for VTO over the previous 12 months, and provide an opportunity for industry, government, and academia to give inputs to DOE with a structured and formal methodology. The meeting also provided attendees with a forum for interaction and technology information transfer.

  18. Rocking or rolling--perception of ambiguous motion after returning from space.

    Directory of Open Access Journals (Sweden)

    Gilles Clément

    Full Text Available The central nervous system must resolve the ambiguity of inertial motion sensory cues in order to derive an accurate representation of spatial orientation. Adaptive changes during spaceflight in how the brain integrates vestibular cues with other sensory information can lead to impaired movement coordination, vertigo, spatial disorientation, and perceptual illusions after return to Earth. The purpose of this study was to compare tilt and translation motion perception in astronauts before and after returning from spaceflight. We hypothesized that these stimuli would be the most ambiguous in the low-frequency range (i.e., at about 0.3 Hz where the linear acceleration can be interpreted either as a translation or as a tilt relative to gravity. Verbal reports were obtained in eleven astronauts tested using a motion-based tilt-translation device and a variable radius centrifuge before and after flying for two weeks on board the Space Shuttle. Consistent with previous studies, roll tilt perception was overestimated shortly after spaceflight and then recovered with 1-2 days. During dynamic linear acceleration (0.15-0.6 Hz, ±1.7 m/s2 perception of translation was also overestimated immediately after flight. Recovery to baseline was observed after 2 days for lateral translation and 8 days for fore-aft translation. These results suggest that there was a shift in the frequency dynamic of tilt-translation motion perception after adaptation to weightlessness. These results have implications for manual control during landing of a space vehicle after exposure to microgravity, as it will be the case for human asteroid and Mars missions.

  19. Conversion of Diesel Vehicles to Electric Vehicles and Controlled by PID Controller

    OpenAIRE

    Mengi, Onur Özdal

    2017-01-01

    Internal combustion engine vehicles are the most producedand sold vehicles on the market. In recent years, interest in electric vehicleshas begun to increase, especially due to the environmental problems. In thenear future, it is estimated that gasoline and diesel vehicles will becompletely electric vehicles. For this reason, many studies have been conductedon electric vehicles. Particularly the change of the engine parts, the turningof the internal combustion part to the electric motor, and ...

  20. Battery control system for hybrid vehicle and method for controlling a hybrid vehicle battery

    Science.gov (United States)

    Bockelmann, Thomas R [Battle Creek, MI; Beaty, Kevin D [Kalamazoo, MI; Zou, Zhanijang [Battle Creek, MI; Kang, Xiaosong [Battle Creek, MI

    2009-07-21

    A battery control system for controlling a state of charge of a hybrid vehicle battery includes a detecting arrangement for determining a vehicle operating state or an intended vehicle operating state and a controller for setting a target state of charge level of the battery based on the vehicle operating state or the intended vehicle operating state. The controller is operable to set a target state of charge level at a first level during a mobile vehicle operating state and at a second level during a stationary vehicle operating state or in anticipation of the vehicle operating in the stationary vehicle operating state. The invention further includes a method for controlling a state of charge of a hybrid vehicle battery.

  1. Design Tool for Estimating Chemical Hydrogen Storage System Characteristics for Light-Duty Fuel Cell Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Kriston P.; Sprik, Sam; Tamburello, David; Thornton, Matthew

    2018-05-03

    The U.S. Department of Energy (DOE) has developed a vehicle framework model to simulate fuel cell-based light-duty vehicle operation for various hydrogen storage systems. This transient model simulates the performance of the storage system, fuel cell, and vehicle for comparison to DOE’s Technical Targets using four drive cycles/profiles. Chemical hydrogen storage models have been developed for the Framework model for both exothermic and endothermic materials. Despite the utility of such models, they require that material researchers input system design specifications that cannot be easily estimated. To address this challenge, a design tool has been developed that allows researchers to directly enter kinetic and thermodynamic chemical hydrogen storage material properties into a simple sizing module that then estimates the systems parameters required to run the storage system model. Additionally, this design tool can be used as a standalone executable file to estimate the storage system mass and volume outside of the framework model and compare it to the DOE Technical Targets. These models will be explained and exercised with existing hydrogen storage materials.

  2. Design Tool for Estimating Chemical Hydrogen Storage System Characteristics for Light-Duty Fuel Cell Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, Matthew J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sprik, Samuel [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Brooks, Kriston P. [Pacific Northwest National Laboratory; Tamburello, David A. [Savannah River National Laboratory

    2018-04-07

    The U.S. Department of Energy (DOE) developed a vehicle Framework model to simulate fuel cell-based light-duty vehicle operation for various hydrogen storage systems. This transient model simulates the performance of the storage system, fuel cell, and vehicle for comparison to Technical Targets established by DOE for four drive cycles/profiles. Chemical hydrogen storage models have been developed for the Framework for both exothermic and endothermic materials. Despite the utility of such models, they require that material researchers input system design specifications that cannot be estimated easily. To address this challenge, a design tool has been developed that allows researchers to directly enter kinetic and thermodynamic chemical hydrogen storage material properties into a simple sizing module that then estimates system parameters required to run the storage system model. Additionally, the design tool can be used as a standalone executable file to estimate the storage system mass and volume outside of the Framework model. These models will be explained and exercised with the representative hydrogen storage materials exothermic ammonia borane (NH3BH3) and endothermic alane (AlH3).

  3. Vibration control of an MR vehicle suspension system considering both hysteretic behavior and parameter variation

    International Nuclear Information System (INIS)

    Choi, Seung-Bok; Seong, Min-Sang; Ha, Sung-Hoon

    2009-01-01

    This paper presents vibration control responses of a controllable magnetorheological (MR) suspension system considering the two most important characteristics of the system; the field-dependent hysteretic behavior of the MR damper and the parameter variation of the suspension. In order to achieve this goal, a cylindrical MR damper which is applicable to a middle-sized passenger car is designed and manufactured. After verifying the damping force controllability, the field-dependent hysteretic behavior of the MR damper is identified using the Preisach hysteresis model. The full-vehicle suspension model is then derived by considering vertical, pitch and roll motions. An H ∞ controller is designed by treating the sprung mass of the vehicle as a parameter variation and integrating it with the hysteretic compensator which produces additional control input. In order to demonstrate the effectiveness and robustness of the proposed control system, the hardware-in-the-loop simulation (HILS) methodology is adopted by integrating the suspension model with the proposed MR damper. Vibration control responses of the vehicle suspension system such as vertical acceleration are evaluated under both bump and random road conditions

  4. MANAJEMEN LABA, RETURN SAHAM, DAN KINERJA OPERASI SEBAGAI PEMODERASI

    Directory of Open Access Journals (Sweden)

    Farid Addy Sumantri

    2017-09-01

    Full Text Available The purpose of this study was to determine the indications of the practice of earnings management at the time of the IPO, one year after the IPO, and two years after the IPO. This study also examined the effect of earnings management on stock returns and operating performance in moderating the relationship between earnings management and stock returns. The study sample comprised 33 firms that go public in the year 2007 to 2011 using a purposive sampling method. Earnings management is proxied by discretionary accruals using the Modified Jones Model, which used proxy for the stock return is cummulative abnormal returns (CAR, while for the company's operating performance used proxy for the return on assets (ROA. The results showed that there were indications of earnings management at the time of the IPO, one year after the IPO, and two years after the IPO with a lower profit rate. No effect on earnings management is proxied by stock return cummulative abnormal returns (CAR. Operating performance of the company also can not moderate the relationship between earnings management with stock return.   Keywords: Earning Management, Initial Public Offering, Cummulative Abnormal Return, Return On Asset

  5. Entry Descent and Landing Workshop Proceedings. Volume 1; Inflatable Reentry Vehicle Experiment-3 (IRVE-3) Project Overview & Instrumentation

    Science.gov (United States)

    Dillman, Robert

    2015-01-01

    Entry mass at Mars is limited by the payload size that can be carried by a rigid capsule that can fit inside the launch vehicle fairing. Landing altitude at Mars is limited by ballistic coefficient (mass per area) of entry body. Inflatable technologies allow payload to use full diameter of launch fairing, and deploy larger aeroshell before atmospheric interface, landing more payload at a higher altitude. Also useful for return of large payloads from Low Earth Orbit (LEO).

  6. The Electric Vehicle Development

    DEFF Research Database (Denmark)

    Wang, Jingyu; Liu, Yingqi; Kokko, Ari

    2014-01-01

    In order to respond to the energy crisis and environment problem, countries carry out their research and promotion about electric vehicles. As the ten cities one thousand new energy buses started in 2009, the new energy vehicles have been greatly developed in China, while the development...... in three aspects-city environment, government and stakeholders. Then the paper discusses the promotion ways and role of government and consumer. Finally, the paper offers some suggestions to promote electric vehicles in China: focusing on feasibility and adaptability of electric vehicles, playing...... of electric vehicles is not that good. This paper selects four cities-Los Angeles, Kanagawa, Hamburg, Amsterdam-that promote electric vehicles successfully and deeply analyzes the development of electric vehicles in these four cities and analyzes the factors that affect the development of electric vehicles...

  7. Modeling and generating input processes

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, M.E.

    1987-01-01

    This tutorial paper provides information relevant to the selection and generation of stochastic inputs to simulation studies. The primary area considered is multivariate but much of the philosophy at least is relevant to univariate inputs as well. 14 refs.

  8. Evaluating the accuracy of vehicle tracking data obtained from Unmanned Aerial Vehicles

    Directory of Open Access Journals (Sweden)

    Giuseppe Guido

    2016-10-01

    Full Text Available This paper presents a methodology for tracking moving vehicles that integrates Unmanned Aerial Vehicles with video processing techniques. The authors investigated the usefulness of Unmanned Aerial Vehicles to capture reliable individual vehicle data by using GPS technology as a benchmark. A video processing algorithm for vehicles trajectory acquisition is introduced. The algorithm is based on OpenCV libraries. In order to assess the accuracy of the proposed video processing algorithm an instrumented vehicle was equipped with a high precision GPS. The video capture experiments were performed in two case studies. From the field, about 24,000 positioning data were acquired for the analysis. The results of these experiments highlight the versatility of the Unmanned Aerial Vehicles technology combined with video processing technique in monitoring real traffic data.

  9. Detection of Water Hazards for Autonomous Robotic Vehicles

    Science.gov (United States)

    Matthes, Larry; Belluta, Paolo; McHenry, Michael

    2006-01-01

    Four methods of detection of bodies of water are under development as means to enable autonomous robotic ground vehicles to avoid water hazards when traversing off-road terrain. The methods involve processing of digitized outputs of optoelectronic sensors aboard the vehicles. It is planned to implement these methods in hardware and software that would operate in conjunction with the hardware and software for navigation and for avoidance of solid terrain obstacles and hazards. The first method, intended for use during the day, is based on the observation that, under most off-road conditions, reflections of sky from water are easily discriminated from the adjacent terrain by their color and brightness, regardless of the weather and of the state of surface waves on the water. Accordingly, this method involves collection of color imagery by a video camera and processing of the image data by an algorithm that classifies each pixel as soil, water, or vegetation according to its color and brightness values (see figure). Among the issues that arise is the fact that in the presence of reflections of objects on the opposite shore, it is difficult to distinguish water by color and brightness alone. Another issue is that once a body of water has been identified by means of color and brightness, its boundary must be mapped for use in navigation. Techniques for addressing these issues are under investigation. The second method, which is not limited by time of day, is based on the observation that ladar returns from bodies of water are usually too weak to be detected. In this method, ladar scans of the terrain are analyzed for returns and the absence thereof. In appropriate regions, the presence of water can be inferred from the absence of returns. Under some conditions in which reflections from the bottom are detectable, ladar returns could, in principle, be used to determine depth. The third method involves the recognition of bodies of water as dark areas in short

  10. Energy savings and increased electric vehicle range through improved battery thermal management

    International Nuclear Information System (INIS)

    Smith, Joshua; Hinterberger, Michael; Schneider, Christoph; Koehler, Juergen

    2016-01-01

    Lithium-ion cells are temperature sensitive: operation outside the optimal operating range causes premature aging and correspondingly reduces vehicle range and battery system lifetime. In order to meet consumer demands for electric and hybrid-electric vehicle performance, especially in adverse climates, a battery thermal management system (BTMS) is often required. This work presents a novel experimental method for analyzing BTMS using three sample cooling plate concepts. For each concept, the input parameters (ambient temperature, coolant temperature and coolant flow rate) are varied and the resulting effect on the average temperature and temperature distribution across and between cells is compared. Additionally, the pressure loss along the coolant path is utilized as an indicator of energy efficiency. Using the presented methodology, various cooling plate layouts optimized for production alternative techniques are compared to the state of the art. It is shown that these production-optimized cooling plates provide sufficient thermal performance with the additional benefit of mechanical integration within the battery and/or vehicle system. It is also shown that the coolant flow influences battery cell thermal behavior more than the solid material and that pressure drop is more sensitive to geometrical changes in the cooling plate than temperature changes at the module.

  11. Evaluation of the return rate of volunteer blood donors

    Directory of Open Access Journals (Sweden)

    Adriana de Fátima Lourençon

    2011-06-01

    Full Text Available BACKGROUND: To convert first-time blood donors into regular volunteer donors is a challenge to transfusion services. OBJECTIVES: This study aims to estimate the return rate of first time donors of the Ribeirão Preto Blood Center and of other blood centers in its coverage region. METHODS: The histories of 115,553 volunteer donors between 1996 and 2005 were analyzed. Statistical analysis was based on a parametric long-term survival model that allows an estimation of the proportion of donors who never return for further donations. RESULTS: Only 40% of individuals return within one year after the first donation and 53% return within two years. It is estimated that 30% never return to donate. Higher return rates were observed among Black donors. No significant difference was found in non-return rates regarding gender, blood type, Rh blood group and blood collection unit. CONCLUSIONS: The low percentage of first-time donors who return for further blood donation reinforces the need for marketing actions and strategies aimed at increasing the return rates.

  12. Electric vehicles and renewable energy in the transport sector - energy system consequences. Main focus: Battery electric vehicles and hydrogen based fuel cell vehicles

    DEFF Research Database (Denmark)

    Nielsen, L.H.; Jørgensen K.

    2000-01-01

    The aim of the project is to analyse energy, environmental and economic aspects of integrating electric vehicles in the future Danish energy system. Consequences of large-scale utilisation of electric vehicles are analysed. The aim is furthermore toillustrate the potential synergistic interplay...... between the utilisation of electric vehicles and large-scale utilisation of fluctuating renewable energy resources, such as wind power. Economic aspects for electric vehicles interacting with a liberalisedelectricity market are analysed. The project focuses on battery electric vehicles and fuel cell...... vehicles based on hydrogen. Based on assumptions on the future technical development for battery electric vehicles, fuel cell vehicles on hydrogen, and forthe conventional internal combustion engine vehicles, scenarios are set up to reflect expected options for the long-term development of road transport...

  13. International Conference on Heavy Vehicles HVParis 2008 : Heavy Vehicle Transport Technology (HVTT 10)

    OpenAIRE

    JACOB, Bernard; NORDENGEN, Paul; O'CONNOR, Alan; BOUTELDJA, Mohamed

    2008-01-01

    Sommaire : Heavy vehicles and WIM technology, testing and standards. Interactions between heavy vehicles or trains and the infrastructure, environment and other system users. Heavy vehicle and road management information: measurements, data quality, data management. Freight mobility and safety. Vehicle classification, size and weight evaluation, regulations and enforcement. Traffic and road safety. WIM of road vehicles, trains and aeroplanes.

  14. Lane-Level Vehicle Trajectory Reckoning for Cooperative Vehicle-Infrastructure System

    Directory of Open Access Journals (Sweden)

    Yinsong Wang

    2012-01-01

    Full Text Available This paper presents a lane-level positioning method by trajectory reckoning without Global Positioning System (GPS equipment in the environment of Cooperative Vehicle-Infrastructure System (CVIS. Firstly, the accuracy requirements of vehicle position in CVIS applications and the applicability of GPS positioning methods were analyzed. Then, a trajectory reckoning method based on speed and steering data from vehicle’s Control Area Network (CAN and roadside calibration facilities was proposed, which consists of three critical models, including real-time estimation of steering angle and vehicle direction, vehicle movement reckoning, and wireless calibration. Finally, the proposed method was validated through simulation and field tests under a variety of traffic conditions. Results show that the accuracy of the reckoned vehicle position can reach the lane level and match the requirements of common CVIS applications.

  15. Return migration as failure or success? : The determinants of return migration intentions among Moroccan migrants in Europe

    NARCIS (Netherlands)

    de Haas, H.; Fokkema, T.; Fihri, M.F.

    2015-01-01

    Different migration theories generate competing hypotheses with regard to determinants of return migration. While neoclassical migration theory associates migration to the failure to integrate at the destination, the new economics of labour migration sees return migration as the logical stage after

  16. How important is vehicle safety for older consumers in the vehicle purchase process?

    Science.gov (United States)

    Koppel, Sjaan; Clark, Belinda; Hoareau, Effie; Charlton, Judith L; Newstead, Stuart V

    2013-01-01

    This study aimed to investigate the importance of vehicle safety to older consumers in the vehicle purchase process. Older (n = 102), middle-aged (n = 791), and younger (n = 109) participants throughout the eastern Australian states of Victoria, New South Wales, and Queensland who had recently purchased a new or used vehicle completed an online questionnaire about their vehicle purchase process. When asked to list the 3 most important considerations in the vehicle purchase process (in an open-ended format), older consumers were mostly likely to list price as their most important consideration (43%). Similarly, when presented with a list of vehicle factors (such as price, design, Australasian New Car Assessment Program [ANCAP] rating), older consumers were most likely to identify price as the most important vehicle factor (36%). When presented with a list of vehicle features (such as automatic transmission, braking, air bags), older consumers in the current study were most likely to identify an antilock braking system (41%) as the most important vehicle feature, and 50 percent of older consumers identified a safety-related vehicle feature as the highest priority vehicle feature (50%). When asked to list up to 3 factors that make a vehicle safe, older consumers in the current study were most likely to list braking systems (35%), air bags (22%), and the driver's behavior or skill (11%). When asked about the influence of safety in the new vehicle purchase process, one third of older consumers reported that all new vehicles are safe (33%) and almost half of the older consumers rated their vehicle as safer than average (49%). A logistic regression model was developed to predict the profile of older consumers more likely to assign a higher priority to safety features in the vehicle purchasing process. The model predicted that the importance of safety-related features was influenced by several variables, including older consumers' beliefs that they could protect themselves

  17. ACL Return to Sport Guidelines and Criteria.

    Science.gov (United States)

    Davies, George J; McCarty, Eric; Provencher, Matthew; Manske, Robert C

    2017-09-01

    Because of the epidemiological incidence of anterior cruciate ligament (ACL) injuries, the high reinjury rates that occur when returning back to sports, the actual number of patients that return to the same premorbid level of competition, the high incidence of osteoarthritis at 5-10-year follow-ups, and the effects on the long-term health of the knee and the quality of life for the patient, individualizing the return to sports after ACL reconstruction (ACL-R) is critical. However, one of the challenging but unsolved dilemmas is what criteria and clinical decision making should be used to return an athlete back to sports following an ACL-R. This article describes an example of a functional testing algorithm (FTA) as one method for clinical decision making based on quantitative and qualitative testing and assessment utilized to make informed decisions to return an athlete to their sports safely and without compromised performance. The methods were a review of the best current evidence to support a FTA. In order to evaluate all the complicated domains of the clinical decision making for individualizing the return to sports after ACL-R, numerous assessments need to be performed including the biopsychosocial concepts, impairment testing, strength and power testing, functional testing, and patient-reported outcomes (PROs). The optimum criteria to use for individualizing the return to sports after ACL-R remain elusive. However, since this decision needs to be made on a regular basis with the safety and performance factors of the patient involved, this FTA provides one method of quantitatively and qualitatively making the decisions. Admittedly, there is no predictive validity of this system, but it does provide practical guidelines to facilitate the clinical decision making process for return to sports. The clinical decision to return an athlete back into competition has significant implications ranging from the safety of the athlete, to performance factors and actual

  18. Wave energy input into the Ekman layer

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This paper is concerned with the wave energy input into the Ekman layer, based on 3 observational facts that surface waves could significantly affect the profile of the Ekman layer. Under the assumption of constant vertical diffusivity, the analytical form of wave energy input into the Ekman layer is derived. Analysis of the energy balance shows that the energy input to the Ekman layer through the wind stress and the interaction of the Stokes-drift with planetary vorticity can be divided into two kinds. One is the wind energy input, and the other is the wave energy input which is dependent on wind speed, wave characteristics and the wind direction relative to the wave direction. Estimates of wave energy input show that wave energy input can be up to 10% in high-latitude and high-wind speed areas and higher than 20% in the Antarctic Circumpolar Current, compared with the wind energy input into the classical Ekman layer. Results of this paper are of significance to the study of wave-induced large scale effects.

  19. Global Variance Risk Premium and Forex Return Predictability

    OpenAIRE

    Aloosh, Arash

    2014-01-01

    In a long-run risk model with stochastic volatility and frictionless markets, I express expected forex returns as a function of consumption growth variances and stock variance risk premiums (VRPs)—the difference between the risk-neutral and statistical expectations of market return variation. This provides a motivation for using the forward-looking information available in stock market volatility indices to predict forex returns. Empirically, I find that stock VRPs predict forex returns at a ...

  20. Investigation of crew performance in a multi-vehicle supervisory control task

    Science.gov (United States)

    Miller, R. A.; Plamondon, B. D.; Jagacinski, R. J.; Kirlik, A. C.

    1986-01-01

    Crew information processing and decision making in a supervisory control task which is loosely based on the mission of future generation helicopters is measured and represented. Subjects control the motion and activities of their own vehicle and direct the activities of four additional craft. The task involves searching an uncertain environment for cargo and enemies, returning cargo to home base and destroying enemies while attempting to avoid destruction of the scout and the supervised vehicles. A series of experiments with two-person crews and one-person crews were performed. Resulting crew performance was modeled with the objective of describing and understanding the information processing strategies utilized. Of particular interest are problem simplification strategies under time stress and high work load, simplification and compensation in the one-person cases, crew coordination in the two-person cases, and the relationship between strategy and errors in all cases. The results should provide some insight into the effective use of aids, particularly aids based on artificial intelligence, for similar tasks. The simulation is described which is used for the study and some preliminary results from the first two-person crew study are discussed.

  1. Statistical analysis of vehicle loads measured with three different vehicle weighing devices

    CSIR Research Space (South Africa)

    Mkhize, ZQP

    2005-07-01

    Full Text Available MEASURED WITH THREE DIFFERENT VEHICLE WEIGHING DEVICES Z Q P MKHIZE and M DE BEER CSIR Transportek, PO Box 395, Pretoria, 0001 ABSTRACT This study introduces a new scale for weighing individual tyres of slow moving vehicles. The new technology... that vehicles exert on pavements plays a vital part in the deterioration of the structural and functional capacity of the road. It also influences the safety of the vehicles, especially when vehicles are operated under overloaded and/or inappropriately loaded...

  2. The impact of vehicle appearance and vehicle behavior on pedestrian interaction with autonomous vehicles

    NARCIS (Netherlands)

    Dey, D.; Martens, M.H.; Eggen, J.H.; Terken, J.M.B.

    2017-01-01

    In this paper, we present the preliminary results of a study that aims to investigate the role of an approaching vehicle's behavior and outer appearance in determining pedestrians' decisions while crossing a street. Concerning appearance, some vehicles are designed to look more assertive than

  3. The Impact of Vehicle Appearance and Vehicle Behavior on Pedestrian Interaction with Autonomous Vehicles

    NARCIS (Netherlands)

    Dey, Debargha; Martens, Marieke; Eggen, Berry; Terken, Jacques

    2017-01-01

    In this paper, we present the preliminary results of a study that aims to investigate the role of an approaching vehicle's behavior and outer appearance in determining pedestrians' decisions while crossing a street. Concerning appearance, some vehicles are designed to look more assertive than

  4. Better understanding flow-restricted environments from hideout return analyses

    International Nuclear Information System (INIS)

    Ollar, Ph.; Viricel-Honorez, L.

    1998-01-01

    Understanding and controlling the chemical phenomena in flow-restricted areas of the secondary side of steam generators (SG) is a key point in fighting against corrosion (IGA) in these areas. Hence, more than 150 hideout returns from French plants are used to assess the chemical environment in flow-restricted areas. The influence of several parameters such as tube support plates design, SG blowdown flowrate and temperature at the end of hideout returns, on returned weights and on flow-restricted environments predicted by modelling are examined. A correlation between different operating and returned chemistry indexes (molar ratios), and IGA is sought: no link is found between IGA and Na/Cl molar ratio at the beginning of hideout returns. However, as IGA extends, the returned weights of sodium and chloride seem to decrease, suggesting a greater hideout and a lower hideout return efficiency, perhaps due to SG fouling, and/or a smaller hideout/hideout return thanks to an improved operating chemistry. Using the pH computed from hideout return data as an index for the presence of IGA is also studied: no correlation is found between the two. Improving plants chemistry is finally proposed, based on an optimization of hideout returns. (authors)

  5. Maternal Dexamethasone Exposure Alters Synaptic Inputs to Gonadotropin-Releasing Hormone Neurons in the Early Postnatal Rat

    Directory of Open Access Journals (Sweden)

    Wei Ling Lim

    2016-08-01

    Full Text Available Maternal dexamethasone (DEX; a glucocorticoid receptor agonist exposure delays pubertal onset and alters reproductive behaviour in the adult offspring. However, little is known whether maternal DEX exposure affects the offspring’s reproductive function by disrupting the gonadotropin-releasing hormone (GnRH neuronal function in the brain. Therefore, this study determined the exposure of maternal DEX on the GnRH neuronal spine development and synaptic cluster inputs to GnRH neurons using transgenic rats expressing enhanced green fluorescent protein (EGFP under the control of GnRH promoter. Pregnant females were administered with DEX (0.1mg/kg or vehicle (VEH, water daily during gestation day 13-20. Confocal imaging was used to examine the spine density of EGFP-GnRH neurons by three-dimensional rendering and synaptic cluster inputs to EGFP-GnRH neurons by synapsin I immunohistochemistry on postnatal day 0 (P0 males. The spine morphology and number on GnRH neurons did not change between the P0 males following maternal DEX and VEH treatment. The number of synaptic clusters within the organum vasculosum of the lamina terminalis (OVLT was decreased by maternal DEX exposure in P0 males. Furthermore, the number and levels of synaptic cluster inputs in close apposition with GnRH neurons was decreased following maternal DEX exposure in the OVLT region of P0 males. In addition, the post synaptic marker molecule, post-synaptic density 95 was observed in GnRH neurons following both DEX and VEH treatment. These results suggest that maternal DEX exposure alters neural afferent inputs to GnRH neurons during early postnatal stage, which could lead to reproductive dysfunction during adulthood.

  6. Protection against malevolent use of vehicles at Nuclear Power Plants. Vehicle barrier system selection guidance

    International Nuclear Information System (INIS)

    Nebuda, D.T.

    1994-08-01

    This manual provides a simplified procedure for selecting land vehicle barriers that will stop the design basis vehicle threat adopted by the U.S. Nuclear Regulatory Commission. Proper selection and construction of vehicle barriers should prevent intrusion of the design basis vehicle. In addition, vital safety related equipment should survive a design basis vehicle bomb attack when vehicle barriers are properly selected, sited, and constructed. This manual addresses passive vehicle barriers, active vehicle barriers, and site design features that can be used to reduce vehicle impact velocity

  7. Electric vehicle market penetration in Switzerland by 2020 - We cannot forecast the future but we can prepare for it

    International Nuclear Information System (INIS)

    2009-07-01

    electric demand by 1.2 to 1.7 TWh a year, i.e. only 1.8 to 2.6 % of the Swiss power generation (66 TWh a year). Simultaneously charging 50% of these electric vehicles would also demand an output power of about 1.3 GW. In a Vision 2020 study entitled 'Electric vehicle market penetration in Switzerland by 2020 (Lausanne and Olten, July 2009)' the Swiss electric utility Alpiq evaluated the impact of such a measure on production and distribution of electric power. Following assumptions were made: 4/5 of the electrical cars would be Plug-in Hybrid Vehicles and 1/5 Battery Electric Vehicles; each car would run 37 km a day on average, or 13,500 km a year; and the mean electric consumption would be 20 kWh for a guaranteed range of 120 km, with one charging at least each third day, mainly slowly in the night ('Sleep and Charge' with a domestic low input power of 3.5 kW for 8 hours), but also quickly ('Coffee and Charge' with a particularly high input power of 55 kW), and with possible intermediate accelerated charging modes ('Work/Shop and Charge' with a mean input power of 7 to 12 kW). Eventually, the number, type and location of the charging facilities needed were estimated on the basis of a characterization of electrical vehicles owners. On the basis of an electric fleet of 720,000 cars, it is concluded that about 650,000 domestic slow charging points, 80,000 private accelerated charging points at working places, 23,000 public accelerated charging points in cities, and 150 quick charging points with each 6 sockets located in ordinary petrol (gas) service stations would be needed

  8. The Returns to Entrepreneurship

    DEFF Research Database (Denmark)

    Van Praag, Mirjam; Raknerud, Arvid

    Empirical studies show low pecuniary returns of switching from wage employment to entrepreneurship. We reconsider the pecuniary gains of this switching by employing a two-stage procedure, where the randomness in the timing of inheritance transfers is used as an exclusion restriction to identify...... causal effects. The model is estimated on data covering the whole Norwegian population of individuals matched to the entire population of firms established in the period 2002-2011. The results indicate that the average returns to entrepreneurship are significantly negative for individuals entering...... entrepreneurship through self-employment and modest, but significantly positive, for incorporated startups....

  9. Battery control system for hybrid vehicle and method for controlling a hybrid vehicle battery

    Science.gov (United States)

    Bockelmann, Thomas R [Battle Creek, MI; Hope, Mark E [Marshall, MI; Zou, Zhanjiang [Battle Creek, MI; Kang, Xiaosong [Battle Creek, MI

    2009-02-10

    A battery control system for hybrid vehicle includes a hybrid powertrain battery, a vehicle accessory battery, and a prime mover driven generator adapted to charge the vehicle accessory battery. A detecting arrangement is configured to monitor the vehicle accessory battery's state of charge. A controller is configured to activate the prime mover to drive the generator and recharge the vehicle accessory battery in response to the vehicle accessory battery's state of charge falling below a first predetermined level, or transfer electrical power from the hybrid powertrain battery to the vehicle accessory battery in response to the vehicle accessory battery's state of charge falling below a second predetermined level. The invention further includes a method for controlling a hybrid vehicle powertrain system.

  10. Mechatronics design and experimental verification of an electric-vehicle-based hybrid thermal management system

    Directory of Open Access Journals (Sweden)

    Yi-Hsuan Hung

    2016-02-01

    Full Text Available In this study, an electric-vehicle-based thermal management system was designed for dual energy sources. An experimental platform developed in a previous study was modified. Regarding the mechanical components, a heat exchanger with a radiator, proportional valve, coolant pipes, and coolant pump was appropriately integrated. Regarding the electric components, two heaters emulating waste heat were controlled using two programmable power supply machines. A rapid-prototyping controller with two temperature inputs and three outputs was designed. Rule-based control strategies were coded to maintain optimal temperatures for the emulated proton exchange membrane fuel cells and lithium batteries. To evaluate the heat power of dual energy sources, driving cycles, energy management control, and efficiency maps of energy sources were considered for deriving time-variant values. The main results are as follows: (a an advanced mechatronics platform was constructed; (b a driving cycle simulation was successfully conducted; and (c coolant temperatures reached their optimal operating ranges when the proportional valve, radiator, and coolant pump were sequentially controlled. The benefits of this novel electric-vehicle-based thermal management system are (a high-efficiency operation of energy sources, (b low occupied volume integrated with energy sources, and (c higher electric vehicle traveling mileage. This system will be integrated with real energy sources and a real electric vehicle in the future.

  11. Designing neuro-fuzzy controller for electromagnetic anti-lock braking system (ABS) on electric vehicle

    Science.gov (United States)

    Pramudijanto, Josaphat; Ashfahani, Andri; Lukito, Rian

    2018-03-01

    Anti-lock braking system (ABS) is used on vehicles to keep the wheels unlocked in sudden break (inside braking) and minimalize the stop distance of the vehicle. The problem of it when sudden break is the wheels locked so the vehicle steering couldn’t be controlled. The designed ABS system will be applied on ABS simulator using the electromagnetic braking. In normal condition or in condition without braking, longitudinal velocity of the vehicle will be equal with the velocity of wheel rotation, so the slip ratio will be 0 (0%) and if the velocity of wheel rotation is 0 (in locked condition) then the wheels will be slip 1 (100%). ABS system will keep the value of slip ratio so it will be 0.2 (20%). In this final assignment, the method that is used is Neuro-Fuzzy method to control the slip value on the wheels. The input is the expectable slip and the output is slip from plant. The learning algorithm which is used is Backpropagation that will work by feedforward to get actual output and work by feedback to get error value with target output. The network that was made based on fuzzy mechanism which are fuzzification, inference and defuzzification, Neuro-fuzzy controller can reduce overshoot plant respond to 43.2% compared to plant respond without controller by open loop.

  12. Communication and collaboration among return-to-work stakeholders.

    Science.gov (United States)

    Russell, Elizabeth; Kosny, Agnieszka

    2018-05-17

    Workers who are injured or become ill on the job are best able to return-to-work when stakeholders involved in their case collaborate and communicate. This study examined health care providers' and case managers' engagement in rehabilitation and return-to-work following workplace injury or illness. In-depth interviews were conducted with 97 health care providers and 34 case managers in four Canadian provinces about their experiences facilitating rehabilitation and return-to-work, and interacting with system stakeholders. A qualitative thematic content analysis demonstrated two key findings. Firstly, stakeholders were challenged to collaborate as a result of: barriers to interdisciplinary and cross-professional communication; philosophical differences about the timing and appropriateness of return-to-work; and confusion among health care providers about the workers' compensation system. Secondly, these challenges adversely affected the co-ordination of patient care, and consequentially, injured workers often became information conduits, and effective and timely treatment and return-to-work was sometimes negatively impacted. Communication challenges between health care providers and case managers may negatively impact patient care and alienate treating health care providers. Discussion about role clarification, the appropriateness of early return-to-work, how paperwork shapes health care providers' role expectations, and strengthened inter-professional communication are considered. Implications for Rehabilitation Administrative and conceptual barriers in workers' compensation systems challenge collaboration and communication between health care providers and case managers. Injured workers may become conduits of incorrect information, resulting in adversarial relationships, overturned health care providers' recommendations, and their disengagement from rehabilitation and return-to-work. Stakeholders should clarify the role of health care providers during

  13. Massive deployment of electrical vehicles on the horizon 2020: an evaluation of the charging facilities; Deploiement massif des vehicules electriques a l'horizon 2020. Evaluation des infrastructures de recharge necessaires

    Energy Technology Data Exchange (ETDEWEB)

    Mean, P.; Gerbex, S. [Alpiq, Lausanne (Switzerland); Studer, Ch. [Alpiq Netz AG, Niedergoesgen (Switzerland)

    2010-07-01

    If 15% of the Swiss cars (i.e. 720,000 units) would be replaced by electrical vehicles, yearly CO{sub 2} emissions would decrease by about 1.2 million tons. This figure must be compared with the international commitment of Switzerland concerning its reduction of the global greenhouse gas emissions by 20%, i.e. 10.5 million tons of CO{sub 2} equivalent a year. These 720,000 electrical vehicles would increase the electric demand by 1.2 to 1.7 TWh a year, i.e. only 1.8 to 2.6 % of the Swiss power generation (66 TWh a year). Simultaneously charging 50% of these electric vehicles would also demand an output power of about 1.3 GW. In a Vision 2020 study entitled 'Electric vehicle market penetration in Switzerland by 2020 (Lausanne and Olten, July 2009)' the Swiss electric utility Alpiq evaluated the impact of such a measure on production and distribution of electric power. Following assumptions were made: 4/5 of the electrical cars would be Plug-in Hybrid Vehicles and 1/5 Battery Electric Vehicles; each car would run 37 km a day on average, or 13,500 km a year; and the mean electric consumption would be 20 kWh for a guaranteed range of 120 km, with one charging at least each third day, mainly slowly in the night ('Sleep and Charge' with a domestic low input power of 3.5 kW for 8 hours), but also quickly ('Coffee and Charge' with a particularly high input power of 55 kW), and with possible intermediate accelerated charging modes ('Work/Shop and Charge' with a mean input power of 7 to 12 kW). Eventually, the number, type and location of the charging facilities needed were estimated on the basis of a characterization of electrical vehicles owners. On the basis of an electric fleet of 720,000 cars, it is concluded that about 650,000 domestic slow charging points, 80,000 private accelerated charging points at working places, 23,000 public accelerated charging points in cities, and 150 quick charging points with each 6 sockets located in

  14. 26 CFR 301.6103(j)(1)-1 - Disclosures of return information reflected on returns to officers and employees of the...

    Science.gov (United States)

    2010-04-01

    ... related activities. 301.6103(j)(1)-1 Section 301.6103(j)(1)-1 Internal Revenue INTERNAL REVENUE SERVICE... and Returns Returns and Records § 301.6103(j)(1)-1 Disclosures of return information reflected on... related activities. (a) General rule. Pursuant to the provisions of section 6103(j)(1) of the Internal...

  15. Predictability of Returns and Cash Flows

    OpenAIRE

    Ralph S.J. Koijen; Stijn Van Nieuwerburgh

    2010-01-01

    We review the literature on return and cash-flow growth predictability from the perspective of the present-value identity. We focus predominantly on recent work. Our emphasis is on U.S. aggregate stock return predictability, but we also discuss evidence from other asset classes and countries.

  16. Return on Investment from Biochar Application

    Science.gov (United States)

    Current literature has yet to fully address the cost of biochar application or the return on investment to the grower. The objectives were to identify possible on-farm spreader equipment, spreader capacity, application expenses, and rate of return needed for growers to apply biochar economically. Bi...

  17. Multiple Attribute Decision Making Based Relay Vehicle Selection for Electric Vehicle Communication

    Directory of Open Access Journals (Sweden)

    Zhao Qiang

    2015-01-01

    Full Text Available Large-scale electric vehicle integration into power grid and charging randomly will cause serious impacts on the normal operation of power grid. Therefore, it is necessary to control the charging behavior of electric vehicle, while information transmission for electric vehicle is significant. Due to the highly mobile characteristics of vehicle, transferring information to power grid directly might be inaccessible. Relay vehicle (RV can be used for supporting multi-hop connection between SV and power grid. This paper proposes a multiple attribute decision making (MADM-based RV selection algorithm, which considers multiple attribute, including data transfer rate, delay, route duration. It takes the characteristics of electric vehicle communication into account, which can provide protection for the communication services of electric vehicle charging and discharging. Numerical results demonstrate that compared to previous algorithm, the proposed algorithm offer better performance in terms of throughput, transmission delay.

  18. Does graded return-to-work improve sick-listed workers' chance of returning to regular working hours?

    Science.gov (United States)

    Høgelund, Jan; Holm, Anders; McIntosh, James

    2010-01-01

    Using Danish register and survey data, we examine the effect of a national graded return-to-work program on the probability of sick-listed workers returning to regular working hours. During program participation, the sick-listed worker works fewer hours and receives the normal hourly wage for the hours worked and sickness benefit for the hours off work. When the worker's health improves, working hours are increased until the sick-listed worker is able to work regular hours. Taking account of unobserved differences between program participants and non-participants, we find that participation in the program significantly increases the probability of returning to regular working hours. Copyright 2009 Elsevier B.V. All rights reserved.

  19. Hybrid neural network bushing model for vehicle dynamics simulation

    International Nuclear Information System (INIS)

    Sohn, Jeong Hyun; Lee, Seung Kyu; Yoo, Wan Suk

    2008-01-01

    Although the linear model was widely used for the bushing model in vehicle suspension systems, it could not express the nonlinear characteristics of bushing in terms of the amplitude and the frequency. An artificial neural network model was suggested to consider the hysteretic responses of bushings. This model, however, often diverges due to the uncertainties of the neural network under the unexpected excitation inputs. In this paper, a hybrid neural network bushing model combining linear and neural network is suggested. A linear model was employed to represent linear stiffness and damping effects, and the artificial neural network algorithm was adopted to take into account the hysteretic responses. A rubber test was performed to capture bushing characteristics, where sine excitation with different frequencies and amplitudes is applied. Random test results were used to update the weighting factors of the neural network model. It is proven that the proposed model has more robust characteristics than a simple neural network model under step excitation input. A full car simulation was carried out to verify the proposed bushing models. It was shown that the hybrid model results are almost identical to the linear model under several maneuvers

  20. Continuous high order sliding mode controller design for a flexible air-breathing hypersonic vehicle.

    Science.gov (United States)

    Wang, Jie; Zong, Qun; Su, Rui; Tian, Bailing

    2014-05-01

    This paper investigates the problem of tracking control with uncertainties for a flexible air-breathing hypersonic vehicle (FAHV). In order to overcome the analytical intractability of this model, an Input-Output linearization model is constructed for the purpose of feedback control design. Then, the continuous finite time convergence high order sliding mode controller is designed for the Input-Output linearization model without uncertainties. In addition, a nonlinear disturbance observer is applied to estimate the uncertainties in order to compensate the controller and disturbance suppression, where disturbance observer and controller synthesis design is obtained. Finally, the synthesis of controller and disturbance observer is used to achieve the tracking for the velocity and altitude of the FAHV and simulations are presented to illustrate the effectiveness of the control strategies. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.