WorldWideScience

Sample records for aerodynamic features vehicle body components

  1. Aerodynamic pitching damping of vehicle-inspired bluff bodies

    Science.gov (United States)

    Tsubokura, Makoto; Cheng, Seeyuan; Nakashima, Takuji; Nouzawa, Takahide; Okada, Yoshihiro

    2010-11-01

    Aerodynamic damping mechanism of road vehicles subjected to pitching oscillation was investigated by using large-eddy simulation technique. The study was based on two kinds of simplified vehicle models, which represent real sedan-type vehicles with different pitching stability in the on-road test. The simplified vehicle modes were developed so as to reproduce the characteristic flow structures above the trunk deck of the real vehicles measured in a wind-tunnel at the static case without oscillation. The forced sinusoidal pitching oscillation was imposed on the models and their pitching damping factors were evaluated through the phase-averaged pitching moment. Then flow structures in the wake of the models were extracted and its contribution to the damping mechanism was discussed. It was found that slight difference of the front and rear pillars' shape drastically affects the flow structures in the wake of the models, which enhance or restrain the vehicles' pitching instability.

  2. Use of bionic inspired surfaces for aerodynamic drag reduction on motor vehicle body panels

    Institute of Scientific and Technical Information of China (English)

    Xiao-wen SONG; Guo-geng ZHANG; Yun WANG; Shu-gen HU

    2011-01-01

    Inspired by the successful applications of biological non-smoothness,we introduced bionic non-smooth surfaces as appendices into vehicle body design,aiming to further reduce aerodynamic drag.The size range of the non-smooth units with pits and grooves was determined according to our analysis with the mechanisms underlying non-smooth unit mediated aerodynamic drag reduction.The bionic non-smooth units reported here were designed to adapt the structure of a given vehicle body from the point of boundary layer control that reduces the burst and the loss of turbulent kinetic energy.The engine cover lid and vehicle body cap were individually treated with the non-smooth units,and the treated vehicles were subjected to aerodynamic drag coefficient simulation tests using the computational fluid dynamics (CFD) analysis method.The simulation results showed that,in comparison with smooth surfaces,properly designed non-smooth surfaces can have greater effects on drag reduction.The mechanism underlying drag reduction mediated by non-smooth surfaces was revealed by further analyses,in which the effects of non-smooth and smooth surfaces were directly compared.

  3. High fidelity quasi steady-state aerodynamic model effects on race vehicle performance predictions using multi-body simulation

    Science.gov (United States)

    Mohrfeld-Halterman, J. A.; Uddin, M.

    2016-07-01

    We described in this paper the development of a high fidelity vehicle aerodynamic model to fit wind tunnel test data over a wide range of vehicle orientations. We also present a comparison between the effects of this proposed model and a conventional quasi steady-state aerodynamic model on race vehicle simulation results. This is done by implementing both of these models independently in multi-body quasi steady-state simulations to determine the effects of the high fidelity aerodynamic model on race vehicle performance metrics. The quasi steady state vehicle simulation is developed with a multi-body NASCAR Truck vehicle model, and simulations are conducted for three different types of NASCAR race tracks, a short track, a one and a half mile intermediate track, and a higher speed, two mile intermediate race track. For each track simulation, the effects of the aerodynamic model on handling, maximum corner speed, and drive force metrics are analysed. The accuracy of the high-fidelity model is shown to reduce the aerodynamic model error relative to the conventional aerodynamic model, and the increased accuracy of the high fidelity aerodynamic model is found to have realisable effects on the performance metric predictions on the intermediate tracks resulting from the quasi steady-state simulation.

  4. Numerical quantification of aerodynamic damping on pitching of vehicle-inspired bluff body

    Science.gov (United States)

    Cheng, S. Y.; Tsubokura, M.; Nakashima, T.; Okada, Y.; Nouzawa, T.

    2012-04-01

    The influence of transient flows on vehicle stability was investigated by large eddy simulation. To consider the dynamic response of a vehicle to real-life transient aerodynamics, a dimensionless parameter that quantifies the amount of aerodynamic damping for vehicle subjects to pitching oscillation is proposed. Two vehicle models with different stability characteristics were created to verify the parameter. For idealized notchback models, underbody has the highest contribution to the total aerodynamic damping, which was up to 69%. However, the difference between the aerodynamic damping of models with distinct A- and C-pillar configurations mainly depends on the trunk-deck contribution. Comparison between dynamically obtained phase-averaged pitching moment with quasi-steady values shows totally different aerodynamic behaviors.

  5. Aerodynamic data of space vehicles

    CERN Document Server

    Weiland, Claus

    2014-01-01

    The capacity and quality of the atmospheric flight performance of space flight vehicles is characterized by their aerodynamic data bases. A complete aerodynamic data base would encompass the coefficients of the static longitudinal and lateral motions and the related dynamic coefficients. In this book the aerodynamics of 27 vehicles are considered. Only a few of them did really fly. Therefore the aerodynamic data bases are often not complete, in particular when the projects or programs were more or less abruptly stopped, often due to political decisions. Configurational design studies or the development of demonstrators usually happen with reduced or incomplete aerodynamic data sets. Therefore some data sets base just on the application of one of the following tools: semi-empirical design methods, wind tunnel tests, numerical simulations. In so far a high percentage of the data presented is incomplete and would have to be verified. Flight mechanics needs the aerodynamic coefficients as function of a lot of var...

  6. Rotor/body aerodynamic interactions

    Science.gov (United States)

    Betzina, M. D.; Smith, C. A.; Shinoda, P.

    1985-01-01

    A wind tunnel investigation was conducted in which independent, steady state aerodynamic forces and moments were measured on a 2.24 m diam. two bladed helicopter rotor and on several different bodies. The mutual interaction effects for variations in velocity, thrust, tip-path-plane angle of attack, body angle of attack, rotor/body position, and body geometry were determined. The results show that the body longitudinal aerodynamic characteristics are significantly affected by the presence of a rotor and hub, and that the hub interference may be a major part of such interaction. The effects of the body on the rotor performance are presented.

  7. Aerodynamic Study about an Automotive Vehicle with Capacity for Only One Occupan

    Directory of Open Access Journals (Sweden)

    Almeida R.A

    2016-04-01

    Full Text Available The presented study describes the aerodynamic behavior of a compact, single occupant, automotive vehicle. To optimize the aerodynamic characteristics of this vehicle, a flow dynamics study was conducted using a virtual model. The outer surfaces of the vehicle body were designed using Computer Aided Design (CAD tools and its aerodynamic performance simulated virtually using Computational Fluid Dynamics (CFD software. Parameters such as pressure coefficient (Cp, coefficient of friction (Cf and graphical analysis of the streamlines were used to understand the flow dynamics and propose recommendations aimed at improving the coefficient of drag (Cd. The identification of interaction points between the fluid and the flow structure was the primary focus of study to develop these propositions. The study of phenomena linked to the characteristics of the model presented here, allowed the identification of design features that should be avoided to generate improved aerodynamic performance

  8. Micro-unmanned aerodynamic vehicle

    Science.gov (United States)

    Reuel, Nigel; Lionberger, Troy A.; Galambos, Paul C.; Okandan, Murat; Baker, Michael S.

    2008-03-11

    A MEMS-based micro-unmanned vehicle includes at least a pair of wings having leading wing beams and trailing wing beams, at least two actuators, a leading actuator beam coupled to the leading wing beams, a trailing actuator beam coupled to the trailing wing beams, a vehicle body having a plurality of fulcrums pivotally securing the leading wing beams, the trailing wing beams, the leading actuator beam and the trailing actuator beam and having at least one anisotropically etched recess to accommodate a lever-fulcrum motion of the coupled beams, and a power source.

  9. Euromech Colloquium 509: Vehicle Aerodynamics. External Aerodynamics of Railway Vehicles, Trucks, Buses and Cars - Proceedings

    OpenAIRE

    Nayeri, Christian Navid; Löfdahl, Lennart; Schober, Martin

    2009-01-01

    During the 509th Colloquium of the Euromech society, held from March 24th & 25th at TU Berlin, fifty leading researchers from all over europe discussed various topics affecting both road vehicle as well as railway vehicle aerodynamics, especially drag reduction (with road vehicles), cross wind stability (with trains) and wake analysis (with both). With the increasing service speed of modern high-speed railway traffic, aerodynamic aspects are gaining importance. The aerodynamic research topics...

  10. Aerodynamic Efficiency Enhancements for Air Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The need for aerodynamics-based efficiency enhancements for air vehicles is presented. The results of the Phase I investigation of concepts for morphing aircraft...

  11. Aerodynamic Efficiency Enhancements for Air Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The need for aerodynamics-based efficiency enhancements for air vehicles is presented. Concepts are presented for morphing aircraft, to enable the aircraft to...

  12. The Aerodynamics of Heavy Vehicles III : Trucks, Buses and Trains

    CERN Document Server

    Orellano, Alexander

    2016-01-01

    This volume contains papers presented at the International conference “The Aerodynamics of Heavy Vehicles III: Trucks, Buses and Trains” held in Potsdam, Germany, September 12-17, 2010 by Engineering Conferences International (ECI). Leading scientists and engineers from industry, universities and research laboratories, including truck and high-speed train manufacturers and operators were brought together to discuss computer simulation and experimental techniques to be applied for the design of more efficient trucks, buses and high-speed trains in the future.   This conference was the third in the series after Monterey-Pacific Groove in 2002 and Lake Tahoe in 2007.  The presentations address different aspects of train aerodynamics (cross wind effects, underbody flow, tunnel aerodynamics and aeroacoustics, experimental techniques), truck aerodynamics (drag reduction, flow control, experimental and computational techniques) as well as computational fluid dynamics and bluff body, wake and jet flows.

  13. Improved Aerodynamic Analysis for Hybrid Wing Body Conceptual Design Optimization

    Science.gov (United States)

    Gern, Frank H.

    2012-01-01

    This paper provides an overview of ongoing efforts to develop, evaluate, and validate different tools for improved aerodynamic modeling and systems analysis of Hybrid Wing Body (HWB) aircraft configurations. Results are being presented for the evaluation of different aerodynamic tools including panel methods, enhanced panel methods with viscous drag prediction, and computational fluid dynamics. Emphasis is placed on proper prediction of aerodynamic loads for structural sizing as well as viscous drag prediction to develop drag polars for HWB conceptual design optimization. Data from transonic wind tunnel tests at the Arnold Engineering Development Center s 16-Foot Transonic Tunnel was used as a reference data set in order to evaluate the accuracy of the aerodynamic tools. Triangularized surface data and Vehicle Sketch Pad (VSP) models of an X-48B 2% scale wind tunnel model were used to generate input and model files for the different analysis tools. In support of ongoing HWB scaling studies within the NASA Environmentally Responsible Aviation (ERA) program, an improved finite element based structural analysis and weight estimation tool for HWB center bodies is currently under development. Aerodynamic results from these analyses are used to provide additional aerodynamic validation data.

  14. Aerodynamic coefficient of vehicle-bridge system by wind tunnel test

    Institute of Scientific and Technical Information of China (English)

    ZHOU Li; GE Yao-jun

    2008-01-01

    The changes of three components of aerodynamic force were discussed with the attack angle conver-sion for three kinds of section models. Based on the project of Shanghai Yangtze River Bridge, the wind tunnel test was conducted to obtain its three components of aerodynamic force including 75 conditions of the construc-tion stage, the bridge without vehicles and the bridge with vehicles from - 12 degrees to + 12 degrees. For the bridge with vehicles, the drag force coefficient and the absolute value of both lift coefficient and moment coeffi-cient were decreased by the vehicles. The test result shows that the bridge railing and vehicles have much influ-ence on the three components of aerodynamic force of the vehicle-bridge system for Shanghai Yangtze River Bridge.

  15. The aerodynamic and structural study of flapping wing vehicles

    OpenAIRE

    Zhou, Liangchen

    2013-01-01

    This thesis reports on the aerodynamic and structural study carried out on flapping wings and flapping vehicles. Theoretical and experimental investigation of aerodynamic forces acting on flapping wings in simple harmonic oscillations is undertaken in order to help conduct and optimize the aerodynamic and structural design of flapping wing vehicles. The research is focused on the large scale ornithopter design of similar size and configuration to a hang glider. By means of Theodorsen’s th...

  16. DOE Project on Heavy Vehicle Aerodynamic Drag

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, R; Salari, K; Ortega, J; Castellucci, P; Pointer, D; Browand, F; Ross, J; Storms, B

    2007-01-04

    Class 8 tractor-trailers consume 11-12% of the total US petroleum use. At highway speeds, 65% of the energy expenditure for a Class 8 truck is in overcoming aerodynamic drag. The project objective is to improve fuel economy of Class 8 tractor-trailers by providing guidance on methods of reducing drag by at least 25%. A 25% reduction in drag would present a 12% improvement in fuel economy at highway speeds, equivalent to about 130 midsize tanker ships per year. Specific goals include: (1) Provide guidance to industry in the reduction of aerodynamic drag of heavy truck vehicles; (2) Develop innovative drag reducing concepts that are operationally and economically sound; and (3) Establish a database of experimental, computational, and conceptual design information, and demonstrate the potential of new drag-reduction devices. The studies described herein provide a demonstration of the applicability of the experience developed in the analysis of the standard configuration of the Generic Conventional Model. The modeling practices and procedures developed in prior efforts have been applied directly to the assessment of new configurations including a variety of geometric modifications and add-on devices. Application to the low-drag 'GTS' configuration of the GCM has confirmed that the error in predicted drag coefficients increases as the relative contribution of the base drag resulting from the vehicle wake to the total drag increases and it is recommended that more advanced turbulence modeling strategies be applied under those circumstances. Application to a commercially-developed boat tail device has confirmed that this restriction does not apply to geometries where the relative contribution of the base drag to the total drag is reduced by modifying the geometry in that region. Application to a modified GCM geometry with an open grille and radiator has confirmed that the underbody flow, while important for underhood cooling, has little impact on the drag

  17. Aerodynamic Optimization of Micro Aerial Vehicle

    Directory of Open Access Journals (Sweden)

    Siew Ping Yeong

    2016-01-01

    Full Text Available Computational fluid dynamics (CFD study was done on the propeller design of a micro aerial vehicle (quadrotor-typed to optimize its aerodynamic performance via Shear Stress Transport K-Omega (SST k-ω turbulence model. The quadrotor model used was WL-V303 Seeker. The design process started with airfoils selection and followed by the evaluation of drone model in hovering and cruising conditions. To sustain a 400g payload, by Momentum Theory an ideal thrust of 5.4 N should be generated by each rotor of the quadrotor and this resulted in an induced velocity of 7.4 m/s on the propeller during hovering phase, equivalent to Reynolds number of 10403 at 75% of the propeller blade radius. There were 6 propellers investigated at this Reynolds number. Sokolov airfoil which produced the largest lift-to-drag ratio was selected for full drone installation to be compared with the original model (benchmark. The CFD results showed that the Sokolov propeller generated 0.76 N of thrust more than the benchmark propeller at 7750 rpm. Despite generating higher thrust, higher drag was also experienced by the drone installed with Sokolov propellers. This resulted in lower lift-to-drag ratio than the benchmark propellers. It was also discovered that the aerodynamic performance of the drone could be further improved by changing the rotating direction of each rotor. Without making changes on the structural design, the drone performance increased by 39.58% in terms of lift-to-drag ratio by using this method.

  18. Aerodynamic and aerothermodynamic analysis of space mission vehicles

    CERN Document Server

    Viviani, Antonio

    2015-01-01

    Presenting an up-to-date view on the most important space vehicle configurations, this book contains detailed analyses for several different type of space mission profiles while considering important factors such as aerodynamic loads, aerodynamic heating, vehicle stability and landing characteristics. With that in mind, the authors provide a detailed overview on different state-of-the-art themes of hypersonic aerodynamics and aerothermodynamics, and consider different space vehicle shapes useful for different space mission objectives. These include: ·        Crew Return Vehicle (CRV) ·        Crew Exploration Vehicle (CEV) ·        Sample Return Vehicle (SRV) ·        Flying Test Bed (FTB). Throughout Aerodynamic and Aerothermodynamic Analysis of Space Mission Vehicles many examples are given, with detailed computations and results for the aerodynamics and aerothermodynamics of all such configurations. Moreover, a final chapter on future launchers is provided and an Appendix on...

  19. Aerodynamic Reconstruction Applied to Parachute Test Vehicle Flight Data Analysis

    Science.gov (United States)

    Cassady, Leonard D.; Ray, Eric S.; Truong, Tuan H.

    2013-01-01

    The aerodynamics, both static and dynamic, of a test vehicle are critical to determining the performance of the parachute cluster in a drop test and for conducting a successful test. The Capsule Parachute Assembly System (CPAS) project is conducting tests of NASA's Orion Multi-Purpose Crew Vehicle (MPCV) parachutes at the Army Yuma Proving Ground utilizing the Parachute Test Vehicle (PTV). The PTV shape is based on the MPCV, but the height has been reduced in order to fit within the C-17 aircraft for extraction. Therefore, the aerodynamics of the PTV are similar, but not the same as, the MPCV. A small series of wind tunnel tests and computational fluid dynamics cases were run to modify the MPCV aerodynamic database for the PTV, but aerodynamic reconstruction of the flights has proven an effective source for further improvements to the database. The acceleration and rotational rates measured during free flight, before parachute inflation but during deployment, were used to con rm vehicle static aerodynamics. A multibody simulation is utilized to reconstruct the parachute portions of the flight. Aerodynamic or parachute parameters are adjusted in the simulation until the prediction reasonably matches the flight trajectory. Knowledge of the static aerodynamics is critical in the CPAS project because the parachute riser load measurements are scaled based on forebody drag. PTV dynamic damping is critical because the vehicle has no reaction control system to maintain attitude - the vehicle dynamics must be understood and modeled correctly before flight. It will be shown here that aerodynamic reconstruction has successfully contributed to the CPAS project.

  20. Aerodynamic Analysis of a Manned Space Vehicle for Missions to Mars

    Directory of Open Access Journals (Sweden)

    Giuseppe Pezzella

    2011-01-01

    Full Text Available The paper deals with the aerodynamic analysis of a manned braking system entering the Mars atmosphere with the aim to support planetary entry system design studies. The exploration vehicle is an axisymmetric blunt body close to the Apollo capsule. Several fully three-dimensional computational fluid dynamics analyses have been performed to address the capsule aerodynamic performance. To this end, a wide range of flow conditions including reacting and nonreacting flow, different angles of attack, and Mach numbers have been investigated and compared. Moreover, nonequilibrium effects on the flow field around the entry vehicle have also been investigated. Results show that real-gas effects, for all the angles of attack considered, increase both the aerodynamic drag and pitching moment whereas the lift is only slighted affected. Finally, results comparisons highlight that experimental and CFD aerodynamic findings available for the Apollo capsule in air adequately represent the static coefficients of the capsule in the Mars atmosphere.

  1. Lateral aerodynamic characteristics of motor vehicles in transient crosswinds

    OpenAIRE

    Cairns, Robert Stuart

    1994-01-01

    Motor car crosswind stability can be adversely affected by reductions in both vehicle mass and drag coefficient. As these are two likely results of future developments the importance of research into vehicle aerodynamic stability is set to increase, moreover, there is evidence that transient effects will be the critical. An experimental facility has been designed and constructed and tests have been carried out to investigate the implications of simulating dynamic flow-fields. Vehicle models o...

  2. Features of somatotype and body weight component composition in patients with acne: boys and girls of Podillya region of Ukraine

    Directory of Open Access Journals (Sweden)

    Gunas Igor

    2016-06-01

    Full Text Available The article describes the differences in peculiarities of somatotype and body weight component composition in patients with acne, the study population being boys and girls of the Podillya region of Ukraine. In the study subjects, regardless of sex, body muscle mass, bone mass and the mesomorphic somatotype component of those with acne were significantly greater, while fat body mass indicators and the endomorphic somatotype component was smaller – in comparison to that of non-afflicted subjects of similar gender. Regarding the ectomorphic component of somatotype, between the surveyed groups of those with and without acne, whether male or female, no significant differences were revealed. For all indicators, whether the somatotype components or the component composition of body weight, between groups of boys or girls with different degrees of severity of acne, again no significant differences were established.

  3. External aerodynamics of heavy ground vehicles: Computations and wind tunnel testing

    Science.gov (United States)

    Bayraktar, Ilhan

    Aerodynamic characteristics of a ground vehicle affect vehicle operation in many ways. Aerodynamic drag, lift and side forces have influence on fuel efficiency, vehicle top speed and acceleration performance. In addition, engine cooling, air conditioning, wind noise, visibility, stability and crosswind sensitivity are some other tasks for vehicle aerodynamics. All of these areas benefit from drag reduction and changing the lift force in favor of the operating conditions. This can be achieved by optimization of external body geometry and flow modification devices. Considering the latter, a thorough understanding of the airflow is a prerequisite. The present study aims to simulate the external flow field around a ground vehicle using a computational method. The model and the method are selected to be three dimensional and time-dependent. The Reynolds-averaged Navier Stokes equations are solved using a finite volume method. The Renormalization Group (RNG) k-epsilon model was elected for closure of the turbulent quantities. Initially, the aerodynamics of a generic bluff body is studied computationally and experimentally to demonstrate a number of relevant issues including the validation of the computational method. Experimental study was conducted at the Langley Full Scale Wind Tunnel using pressure probes and force measurement equipment. Experiments and computations are conducted on several geometric configurations. Results are compared in an attempt to validate the computational model for ground vehicle aerodynamics. Then, the external aerodynamics of a heavy truck is simulated using the validated computational fluid dynamics method, and the external flow is presented using computer visualization. Finally, to help the estimation of the error due to two commonly practiced engineering simplifications, a parametric study on the tires and the moving ground effect are conducted on full-scale tractor-trailer configuration. Force and pressure coefficients and velocity

  4. STUDY ON AERODYNAMIC CHARACTERISTICS OF VAN-BODY TRUCKS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The aerodynamic characteristics of the van-body truck were studied by means of theoretical analysis, numerical simulation and wind tunnel experiments. The concept of critical length was presented for the van-body truck in wind tunnel experiments, the proper critical Reynolds number was found and the effects of ground parameters in ground effect simulation on the aerodynamic measurements were examined. It shows that two structure parameters, van height and the gap between the cab and the van, can obviously influence the aerodynamic characteristics, and the additional aerodynamic devices, the wind deflector and the vortex regulator in the rear, can considerably reduce the aerodynamic drag of the van-body truck. Numerical simulations provided rich information of the flow fields around the van-body trucks.

  5. Methods of reducing vehicle aerodynamic drag

    Energy Technology Data Exchange (ETDEWEB)

    Sirenko V.; Rohatgi U.

    2012-07-08

    A small scale model (length 1710 mm) of General Motor SUV was built and tested in the wind tunnel for expected wind conditions and road clearance. Two passive devices, rear screen which is plate behind the car and rear fairing where the end of the car is aerodynamically extended, were incorporated in the model and tested in the wind tunnel for different wind conditions. The conclusion is that rear screen could reduce drag up to 6.5% and rear fairing can reduce the drag by 26%. There were additional tests for front edging and rear vortex generators. The results for drag reduction were mixed. It should be noted that there are aesthetic and practical considerations that may allow only partial implementation of these or any drag reduction options.

  6. Wind machines. [aerodynamics of sailwing vehicles

    Science.gov (United States)

    Lissaman, P. B. S.

    1973-01-01

    The basic elements of the air/water momentum exchange are described by the environment, the potential, the air and water subsystems, the total system, and the rule. Many of these topics have direct analogues in aerogenerator design. Aspects of optimal sail design and of waveless hulls are briefly outlined. A wind driven vehicle capable of moving directly downwind faster than the wind, is reported. The lecture is illustrated with slides and movie clips showing surfing catamarans, land and water versions of the Bauer vehicle, hang gliding, land sailing, and wind surfing.

  7. Research on the Aerodynamic Lift of Vehicle Windshield Wiper

    Directory of Open Access Journals (Sweden)

    Gu Zhengqi

    2016-01-01

    Full Text Available Currently, research on the aerodynamic lift of vehicle windshield wipers is confined to the steady results, and there are very few test results. In the face of this truth, a wind tunnel test is conducted by using the Multipoint Film Force Test System (MFF. In this test, the aerodynamic lift of four kinds of wiper is measured at different wind speeds and different rotation angles. And then, relevant steady-state numerical simulations are accomplished and the mechanism of the aerodynamic lift is analyzed. Furthermore, combined with dynamic meshing and user-defined functions (UDF, transient aerodynamic characteristics of wipers are obtained through numerical simulations. It is found that the aerodynamic lift takes great effect on the stability of wipers, and there is maximum value of the lift near a certain wind speed and rotation angle. The lift force when wipers are rotating with the free stream is less than steady, and the force when rotating against the free stream is greater than steady.

  8. Aerodynamic Drag Reduction for Ground Vehicles using Lateral Guide Vanes

    Directory of Open Access Journals (Sweden)

    Essam Wahba

    2012-06-01

    Full Text Available The use of lateral guide vanes as a drag reducing device for ground vehicles is numerically investigated in the present study. Two types of ground vehicles are considered, a simplified bus model and a simplified sport utility vehicle (SUV model. The guide vanes are used to direct air into the low-pressure wake region in order to enhance pressure recovery, which in turn would reduce form drag and hence the overall aerodynamic drag. Computational fluid dynamics simulations are used to assess the efficiency of the drag reducing device. The steady-state simulations are based on the Reynolds-averaged Navier-Stokes equations, with turbulence closure provided through two-equation eddy-viscosity models. Guide vane cross-section, chord length and angle of attack are varied in order to obtain the optimal configuration for improved aerodynamic performance. Simulations indicate an overall reduction in the aerodynamic drag coefficient of up to 18% for the bus and SUV models with the use of the lateral guide vanes. Grid-independence tests and comparison with available data in the literature is carried out to validate the present numerical procedure.

  9. Experimental Analysis of Aerodynamic Aspects of Sport Utility Vehicle

    Directory of Open Access Journals (Sweden)

    DINESH Y DHANDE

    2013-07-01

    Full Text Available In an era fuel efficiency has become topic of discussion not only among the scholar researchers but also common men. As rapid and continuous increase in prizes of fuels consumers are going for most fuel efficient vehicles. By aerodynamic styling of vehicle one can not only improve the fuel efficiency but also ensure better stability and good handling characteristics of vehicles at higher speed especially on highways. The paper describes assessment of drag force (Fd and drag coefficient (Cd by conventional wind tunnel method. Theexperimental calculations were performed on subsonic wind tunnel having test section of 100cm x 30cm x 30 cm. Exact replica of model of sports utility vehicle (suv on reduced scale 1:32 is used to for experimentation to calculate Fd and Cd.

  10. Software Component Technologies for Heavy Vehicles

    OpenAIRE

    Möller, Anders

    2005-01-01

    Control-systems for heavy vehicles have advanced from an area where Industrial Requirements on Component Technologies for Embedded Systemsmainly mechanic and hydraulic solutions were used, to a highly computerised domain using distributed embedded real-time computer systems. To cope with the increasing level of end-customer demands on advanced features and functions in future vehicle systems, sophisticated development techniques are needed. The development techniques must support software in ...

  11. Innovation in Aerodynamic Design Features of Soviet Missiles

    Science.gov (United States)

    Spearman, M. Leroy

    2006-01-01

    Wind tunnel investigations of some tactical and strategic missile systems developed by the former Soviet Union have been included in the basic missile research programs of the NACA/NASA. Studies of the Soviet missiles sometimes revealed innovative design features that resulted in unusual or unexpected aerodynamic characteristics. In some cases these characteristics have been such that the measured performance of the missile exceeds what might have been predicted. In other cases some unusual design features have been found that would alleviate what might otherwise have been a serious aerodynamic problem. In some designs, what has appeared to be a lack of refinement has proven to be a matter of expediency. It is a purpose of this paper to describe some examples of unusual design features of some Soviet missiles and to illustrate the effectiveness of the design features on the aerodynamic behavior of the missile. The paper draws on the experience of the author who for over 60 years was involved in the aerodynamic wind tunnel testing of aircraft and missiles with the NACA/NASA.

  12. Aerodynamic, structural, and trajectory analysis of ASTRID-1 vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Glover, L.S.; Iwaskiw, A.P.; Oursler, M.A.; Perini, L.L.; Schaefer, E.D.

    1994-02-10

    The Johns Hopkins University/Applied Physics Laboratory, JHU/API, in support of Lawrence Livermore National Laboratory, LLNL, is conducting aerodynamic, trajectory, and structural analysis of the Advanced Single Stage Technology Rapid Insertion Demonstration (ASTRID) vehicle, being launched out of Vandenberg Air Force Base (VAFB) in February 1994. The launch is designated ASTRID-1 and is the first in a series of three that will be launched out of VAFB. Launch dates for the next two flights have not been identified, but they are scheduled for the 1994-1995 time frame. The primary goal of the ASTRID-1 flight is to test the LLNL light weight thrust on demand bi-propellant pumped divert propulsion system. The system is employed as the main thrusters for the ASTRID-1 vehicle and uses hydrazine as the mono-propellant. The major conclusions are: (1) The vehicle is very stable throughout flight (stability margin = 17 to 24 inches); (2) The aerodynamic frequency and the roll rate are such that pitch-roll interactions will be small; (3) The high stability margin combined with the high launcher elevation angle makes the vehicle flight path highly sensitive to perturbations during the initial phase of flight, i.e., during the first second of flight after leaving the rail; (4) The major impact dispersions for the test flight are due to winds. The wind impact dispersions are 90% dictated by the low altitude, 0 to 1000 ft., wind conditions; and (5) In order to minimize wind dispersions, head wind conditions are favored for the launch as November VAFB mean tail winds result in land impacts. The ballistic wind methodology can be employed to assess the impact points of winds at the launch site.

  13. Fluidic Control of Aerodynamic Forces on an Axisymmetric Body

    Science.gov (United States)

    Abramson, Philip; Vukasinovic, Bojan; Glezer, Ari

    2007-11-01

    The aerodynamic forces and moments on a wind tunnel model of an axisymmetric bluff body are modified by induced local vectoring of the separated base flow. Control is effected by an array of four integrated aft-facing synthetic jets that emanate from narrow, azimuthally-segmented slots, equally distributed around the perimeter of the circular tail end within a small backward facing step that extends into a Coanda surface. The model is suspended in the wind tunnel by eight thin wires for minimal support interference with the wake. Fluidic actuation results in a localized, segmented vectoring of the separated base flow along the rear Coanda surface and induces asymmetric aerodynamic forces and moments to effect maneuvering during flight. The aerodynamic effects associated with quasi-steady and transitory differential, asymmetric activation of the Coanda effect are characterized using direct force and PIV measurements.

  14. Aerodynamic drag reduction of a simplified squareback vehicle using steady blowing

    Science.gov (United States)

    Littlewood, R. P.; Passmore, M. A.

    2012-08-01

    A large contribution to the aerodynamic drag of a vehicle arises from the failure to fully recover pressure in the wake region, especially on squareback configurations. A degree of base pressure recovery can be achieved through careful shape optimisation, but the freedom of an automotive aerodynamicist to implement significant shape changes is limited by a variety of additional factors such styling, ergonomics and loading capacity. Active flow control technologies present the potential to create flow field modifications without the need for external shape changes and have received much attention in previous years within the aeronautical industry and, more recently, within the automotive industry. In this work the influence of steady blowing applied at a variety of angles on the roof trailing edge of a simplified ¼ scale squareback style vehicle has been investigated. Hot-wire anemometry, force balance measurements, surface pressure measurements and PIV have been used to investigate the effects of the steady blowing on the vehicle wake structures and the resulting body forces. The energy consumption of the steady jet is calculated and is used to deduce an aerodynamic drag power change. Results show that overall gains can be achieved; however, the large mass flow rate required restricts the applicability of the technique to road vehicles. Means by which the mass flow rate requirements of the jet may be reduced are discussed and suggestions for further work put forward.

  15. Control of maglev vehicles with aerodynamic and guideway disturbances

    Science.gov (United States)

    Flueckiger, Karl; Mark, Steve; Caswell, Ruth; Mccallum, Duncan

    1994-01-01

    A modeling, analysis, and control design methodology is presented for maglev vehicle ride quality performance improvement as measured by the Pepler Index. Ride quality enhancement is considered through active control of secondary suspension elements and active aerodynamic surfaces mounted on the train. To analyze and quantify the benefits of active control, the authors have developed a five degree-of-freedom lumped parameter model suitable for describing a large class of maglev vehicles, including both channel and box-beam guideway configurations. Elements of this modeling capability have been recently employed in studies sponsored by the U.S. Department of Transportation (DOT). A perturbation analysis about an operating point, defined by vehicle and average crosswind velocities, yields a suitable linearized state space model for multivariable control system analysis and synthesis. Neglecting passenger compartment noise, the ride quality as quantified by the Pepler Index is readily computed from the system states. A statistical analysis is performed by modeling the crosswind disturbances and guideway variations as filtered white noise, whereby the Pepler Index is established in closed form through the solution to a matrix Lyapunov equation. Data is presented which indicates the anticipated ride quality achieved through various closed-loop control arrangements.

  16. Radiation curing of composites for vehicle component and vehicle manufacture

    International Nuclear Information System (INIS)

    Some traditional uses of metals in vehicle component and vehicle manufacture, such as steel (specific gravity 7.8) or aluminum (specific gravity 2.7), can be replaced by carbon-fiber composites (specific gravity 1.6) to provide significant weight savings while maintaining structural integrity. The aerospace and aircraft industries have adopted this approach. The auto or motor vehicle industries have explored the use of composites, but have been reluctant to widely adopt this technology because of concerns over manufacturing processes. A typical steel auto body weighing ∼ 750 kilos would weigh only ∼ 155 kilos if replaced with carbon-fiber composites. Structural members, as the vehicle chassis, could also be fabricated out of carbon-fiber composites. With only 20% of the body weight, smaller, lower horse-power and more fuel efficient engines could be used to power such vehicles. Commercial aircraft manufacturers that have adopted carbon-fiber structures in lieu of aluminum (a 40% weight savings) estimate a 20% savings in fuel costs for large planes. These are still made with conventional materials being used for motors, tires, interiors, and the like. A fuel efficient auto now running at ∼ 10 kilometers/liter would more than double its fuel efficiency given the nearly 80% weight savings attainable by use of carbon-fiber composites just for the vehicle body. As with aircraft, conventional systems for propulsion (motors), braking, tires and interiors could still be used. Radiation curing can simplify the manufacture of carbon-fiber composite vehicle components. Highly penetrating X-rays derived from high current, high energy electron beam (EB) accelerators can be used to cure structural composites while they are constrained within inexpensive molds; thus reducing cure cycles, eliminating heat transfer concerns and concerns over potentially hazardous emissions during the curing process. Since X-rays can penetrate mold walls, the curing process is quite versatile

  17. Radiation curing of composites for vehicle component and vehicle manufacture

    International Nuclear Information System (INIS)

    Some ordinary uses of metals in vehicle components and vehicle manufacture, such as steel (specific gravity 7.8) or aluminum (specific gravity 2.7), can be replaced by carbon fiber composites (specific gravity 1.6) to provide significant weight savings while still maintaining structural integrity. The aircraft and aerospace industries have adopted this concept. The motor vehicle industry is using composite materials for some nonstructural components in automobiles, but have been reluctant to widely adopt this technology because of concerns about thermal curing times and other issues in high-volume manufacturing processes. A typical steel auto body weighing ∼750 kilograms would weigh only ∼155 kilograms if replaced with carbon fiber composites. Structural members, such as the vehicle chassis and body frame, could also be made out of carbon fiber composites. With only 20% of the typical body weight, smaller, lighter, less powerful and more fuel efficient engines could be used in such vehicles. Commercial aircraft manufacturers have adopted large carbon fiber structures in lieu of aluminum for a 40% weight reduction and estimate a 20% savings in fuel costs for large planes. These aircraft still use conventional materials for motors, tires and interior components. The fuel efficiency of an automobile could be doubled with an 80% weight reduction. As with aircraft, conventional motors, tires and interior components could be used in automobiles. Radiation curing can simplify the manufacture of carbon fiber composites. Penetrating X-rays generated with high-energy, high-power electron beam (EB) accelerators can cure structural composites while they are constrained within inexpensive molds; thus reducing cure times, eliminating heat transfer concerns and potentially hazardous volatile emissions during the curing process. Since X-rays can penetrate mold walls, the curing process is quite versatile, enabling diverse components with varying designs to be cured using a

  18. Particle Methods in Bluff Body Aerodynamics

    DEFF Research Database (Denmark)

    Rasmussen, Johannes Tophøj

    Fluid-structure interaction is studied numerically in academics and the industry. Shear computational power alone is insufficient to accurately resolve the complex dynamics of high Reynolds number fluid flow. Therefore the development of more efficient and applicable computational algorithms...... of the flow. The method is validated by simulating the turbulent flow past a flat plate and past the Great Belt East bridge, the Øresund bridge and the Busan-Geoje bridge. The dissertation introduces a novel multiresolution vortex-in-cell algorithm using patches of varying resolution. The Poisson equation....... The implementation is two-dimensional and sequential. The implementation is validated against the analytic solution to the Perlman test case and by free-space simulations of the onset flow around fixed and rotating circular cylinders and bluff body flows around bridge sections. Finally a three-dimensional vortex...

  19. The space shuttle ascent vehicle aerodynamic challenges configuration design and data base development

    Science.gov (United States)

    Dill, C. C.; Young, J. C.; Roberts, B. B.; Craig, M. K.; Hamilton, J. T.; Boyle, W. W.

    1985-01-01

    The phase B Space Shuttle systems definition studies resulted in a generic configuration consisting of a delta wing orbiter, and two solid rocket boosters (SRB) attached to an external fuel tank (ET). The initial challenge facing the aerodynamic community was aerodynamically optimizing, within limits, this configuration. As the Shuttle program developed and the sensitivities of the vehicle to aerodynamics were better understood the requirements of the aerodynamic data base grew. Adequately characterizing the vehicle to support the various design studies exploded the size of the data base to proportions that created a data modeling/management challenge for the aerodynamicist. The ascent aerodynamic data base originated primarily from wind tunnel test results. The complexity of the configuration rendered conventional analytic methods of little use. Initial wind tunnel tests provided results which included undesirable effects from model support tructure, inadequate element proximity, and inadequate plume simulation. The challenge to improve the quality of test results by determining the extent of these undesirable effects and subsequently develop testing techniques to eliminate them was imposed on the aerodynamic community. The challenges to the ascent aerodynamics community documented are unique due to the aerodynamic complexity of the Shuttle launch. Never before was such a complex vehicle aerodynamically characterized. The challenges were met with innovative engineering analyses/methodology development and wind tunnel testing techniques.

  20. Hybrid CFD/FEM-BEM simulation of cabin aerodynamic noise for vehicles traveling at high speed

    Institute of Scientific and Technical Information of China (English)

    WANG; YiPing; ZHEN; Xin; WU; Jing; GU; ZhengQi; XIAO; ZhenYi; YANG; Xue

    2013-01-01

    Flow passing a vehicle may lead to the increase of the cabin interior noise level through a variety of mechanisms. These mechanisms include vibrations caused by aerodynamic excitations and reradiation from the glass panels, exterior noise trans-mitted and leaked through door seals including gaps and glass edge, and transmission of airborne noise generated by the interaction of flow with body panels. It is of vital importance to predict both the flow fields and the acoustic sources around the ve-hicle to accurately assess the impact of wind induced noise inside the cabin. In the present study, an unstructured segregated finite volume model was used to calculate the flow fields in which a hexahedron grid is used to simplify the vehicle geometry.A large eddy simulation coupled with a wall function model was applied to predict the exterior transient flow fields. The mean flow quantities were thus calculated along the symmetry plane and the vehicle’s side windows. A coupled FEM/BEM method was used to compute the vehicle’s interior noise level. The total contribution of the interior noise level due to the body panels of the vehicle was subsequently analyzed.

  1. Acoustic Signal Feature Extraction of Vehicle Targets

    Institute of Scientific and Technical Information of China (English)

    蓝金辉; 马宝华; 李科杰

    2002-01-01

    Acoustic signal feature extraction is an important part of target recognition. The mechanisms for producing acoustic signals and their propagation are analyzed to extract the features of the radiated noise from different targets. Analysis of the acoustic spectra of typical vehicle targets acquired outdoors shows that the vehicles can be classified based on the acoustic spectra and amplitudes.

  2. FY2003 Annual Report: DOE Project on Heavy Vehicle Aerodynamic Drag

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, R C; Salari, K; Ortega, J; DeChant, L J; Roy, C J; Payne, J J; Hassan, B; Pointer, W D; Browand, F; Hammache, M; Hsu, T; Ross, J; Satran, D; Heineck, J; Walker, S; Yaste, D; Englar, R; Leonard, A; Rubel, M; Chatelain, P

    2003-10-24

    Objective: {sm_bullet} Provide guidance to industry in the reduction of aerodynamic drag of heavy truck vehicles. {sm_bullet} Establish a database of experimental, computational, and conceptual design information, and demonstrate potential of new drag-reduction devices.

  3. Aerodynamic drag reduction apparatus for gap-divided bluff bodies such as tractor-trailers

    Science.gov (United States)

    Ortega, Jason M.; Salari, Kambiz

    2006-07-11

    An apparatus for reducing the aerodynamic drag of a bluff-bodied vehicle such as a tractor-trailer in a flowstream, the bluff-bodied vehicle of a type having a leading portion, a trailing portion connected to the leading portion, and a gap between the leading and trailing portions defining a recirculation zone. The apparatus is preferably a baffle assembly, such as a vertical panel, adapted to span a width of the gap between the leading and trailing portions so as to impede cross-flow through the gap, with the span of the baffle assembly automatically adjusting for variations in the gap width when the leading and trailing portions pivot relative to each other.

  4. Aerodynamic Design Methodology for Blended Wing Body Transport

    Institute of Scientific and Technical Information of China (English)

    LI Peifeng; ZHANG Binqian; CHEN Yingchun; YUAN Changsheng; LIN Yu

    2012-01-01

    This paper puts forward a design idea for blended wing body (BWB).The idea is described as that cruise point,maximum lift to drag point and pitch trim point are in the same flight attitude.According to this design idea,design objectives and constraints are defined.By applying low and high fidelity aerodynamic analysis tools,BWB aerodynamic design methodology is established by the combination of optimization design and inverse design methods.High lift to drag ratio,pitch trim and acceptable buffet margin can be achieved by this design methodology.For 300-passenger BWB configuration based on static stability design,as compared with initial configuration,the maximum lift to drag ratio and pitch trim are achieved at cruise condition,zero lift pitching moment is positive,and buffet characteristics is well.Fuel burn of 300-passenger BWB configuration is also significantly reduced as compared with conventional civil transports.Because aerodynamic design is carried out under the constraints of BWB design requirements,the design configuration fulfills the demands for interior layout and provides a solid foundation for continuous work.

  5. Quasi steady-state aerodynamic model development for race vehicle simulations

    Science.gov (United States)

    Mohrfeld-Halterman, J. A.; Uddin, M.

    2016-01-01

    Presented in this paper is a procedure to develop a high fidelity quasi steady-state aerodynamic model for use in race car vehicle dynamic simulations. Developed to fit quasi steady-state wind tunnel data, the aerodynamic model is regressed against three independent variables: front ground clearance, rear ride height, and yaw angle. An initial dual range model is presented and then further refined to reduce the model complexity while maintaining a high level of predictive accuracy. The model complexity reduction decreases the required amount of wind tunnel data thereby reducing wind tunnel testing time and cost. The quasi steady-state aerodynamic model for the pitch moment degree of freedom is systematically developed in this paper. This same procedure can be extended to the other five aerodynamic degrees of freedom to develop a complete six degree of freedom quasi steady-state aerodynamic model for any vehicle.

  6. Aerodynamics of Race Cars

    Science.gov (United States)

    Katz, Joseph

    2006-01-01

    Race car performance depends on elements such as the engine, tires, suspension, road, aerodynamics, and of course the driver. In recent years, however, vehicle aerodynamics gained increased attention, mainly due to the utilization of the negative lift (downforce) principle, yielding several important performance improvements. This review briefly explains the significance of the aerodynamic downforce and how it improves race car performance. After this short introduction various methods to generate downforce such as inverted wings, diffusers, and vortex generators are discussed. Due to the complex geometry of these vehicles, the aerodynamic interaction between the various body components is significant, resulting in vortex flows and lifting surface shapes unlike traditional airplane wings. Typical design tools such as wind tunnel testing, computational fluid dynamics, and track testing, and their relevance to race car development, are discussed as well. In spite of the tremendous progress of these design tools (due to better instrumentation, communication, and computational power), the fluid dynamic phenomenon is still highly nonlinear, and predicting the effect of a particular modification is not always trouble free. Several examples covering a wide range of vehicle shapes (e.g., from stock cars to open-wheel race cars) are presented to demonstrate this nonlinear nature of the flow field.

  7. Some Features of Aerodynamics of Cyclonic Chamber with Free Exit

    Directory of Open Access Journals (Sweden)

    A. N. Orekhov

    2014-06-01

    Full Text Available The paper cites results of an experimental research in aerodynamics of a cyclonic chamber with a free exit that has a large relative length. Distributions of aerodynamic stream characteristics depending on geometry of working volume of the cyclonic chamber are given in the paper. Calculative dependences are proposed in the paper.

  8. 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

    Presented is a computer-based tool that connects several disciplines that are needed in the complex and integrated design of high performance reusable single stage to orbit (SSTO) vehicles. Every system is linked to every other system, as is the case of SSTO vehicles with air breathing propulsion, which is currently being studied by NASA. An RBCC propulsion system integrates airbreathing and rocket propulsion into a single engine assembly enclosed within a cowl or duct. A typical RBCC propulsion system operates as a ducted rocket up to approximately Mach 3. Then there is a transition to a ramjet mode for supersonic-to-hypersonic acceleration. Around Mach 8 the engine transitions to a scramjet mode. During the ramjet and scramjet modes, the integral rockets operate as fuel injectors. Around Mach 10-12 (the actual value depends on vehicle and mission requirements), the inlet is physically closed and the engine transitions to an integral rocket mode for orbit insertion. A common feature of RBCC propelled vehicles is the high degree of integration between the propulsion system and airframe. At high speeds the vehicle forebody is fundamentally part of the engine inlet, providing a compression surface for air flowing into the engine. The compressed air is mixed with fuel and burned. The combusted mixture must be expanded to an area larger than the incoming stream to provide thrust. Since a conventional nozzle would be too large, the entire lower after body of the vehicle is used as an expansion surface. Because of the high external temperatures seen during atmospheric flight, the design of an airbreathing SSTO vehicle requires delicate tradeoffs between engine design, vehicle shape, and thermal protection system (TPS) sizing in order to produce an optimum system in terms of weight (and cost) and maximum performance. To adequately determine the performance of the engine/vehicle, the Hypersonic Flight Inlet Model (HYFIM) module was designed to interface with the RBCC

  9. Aerodynamic flight control to increase payload capability of future launch vehicles

    Science.gov (United States)

    Cochran, John E., Jr.; Cheng, Y.-M.; Leleux, Todd; Bigelow, Scott; Hasbrook, William

    1993-01-01

    In this report, we provide some examples of French, Russian, Chinese, and Japanese launch vehicles that have utilized fins in their designs. Next, the aerodynamic design of the fins is considered in Section 3. Some comments on basic static stability and control theory are followed by a brief description of an aerodynamic characteristics prediction code that was used to estimate the characteristics of a modified NLS 1.5 Stage vehicle. Alternative fin designs are proposed and some estimated aerodynamic characteristics presented and discussed. Also included in Section 3 is a discussion of possible methods of enhancement of the aerodynamic efficiency of fins, such as vortex generators and jet flaps. We consider the construction of fins for launch vehicles in Section 4 and offer an assessment of the state-of-the-art in the use of composites for aerodynamic control surfaces on high speed vehicles. We also comment on the use of smart materials for launch vehicle fins. The dynamic stability and control of a launch vehicle that utilizes both thrust vector control (engine nozzle gimballing) and movable fins is the subject addressed in Section 5. We give a short derivation of equations of motion for a launch vehicle moving in a vertical plane above a spherical earth, discuss the use of a gravity-turn nominal trajectory, and give the form of the period equations linearized about such a nominal. We then consider feedback control of vehicle attitude using both engine gimballing and fin deflection. Conclusions are stated and recommendations made in Section 6. An appendix contains aerodynamic data in tabular and graphical formats.

  10. On the Deflexion of Anisotropic Structural Composite Aerodynamic Components

    Directory of Open Access Journals (Sweden)

    J. Whitty

    2014-01-01

    Full Text Available This paper presents closed form solutions to the classical beam elasticity differential equation in order to effectively model the displacement of standard aerodynamic geometries used throughout a number of industries. The models assume that the components are constructed from in-plane generally anisotropic (though shown to be quasi-isotropic composite materials. Exact solutions for the displacement and strains for elliptical and FX66-S-196 and NACA 63-621 aerofoil approximations thin wall composite material shell structures, with and without a stiffening rib (shear-web, are presented for the first time. Each of the models developed is rigorously validated via numerical (Runge-Kutta solutions of an identical differential equation used to derive the analytical models presented. The resulting calculated displacement and material strain fields are shown to be in excellent agreement with simulations using the ANSYS and CATIA commercial finite element (FE codes as well as experimental data evident in the literature. One major implication of the theoretical treatment is that these solutions can now be used in design codes to limit the required displacement and strains in similar components used in the aerospace and most notably renewable energy sectors.

  11. Vehicle Tracking Using Kalman Filter and Features

    Directory of Open Access Journals (Sweden)

    Amir Salarpour

    2011-09-01

    Full Text Available Vehicle tracking has a wide variety of applications. The image resolution of the video available from most traffic camera system is low. In many cases for tracking multi object, distinguishing them from another isn’t easy because of their similarity. In this paper we describe a method, for tracking multiple objects, where the objects are vehicles. The number of vehicles is unknown and varies. We detect all moving objects, and for tracking of vehicle we use the kalman filter and color feature and distance of it from one frame to the next. So the method can distinguish and tracking all vehicles individually. The proposed algorithm can be applied to multiple moving objects.

  12. Component Control System for a Vehicle

    Science.gov (United States)

    Fraser-Chanpong, Nathan (Inventor); Spain, Ivan (Inventor); Dawson, Andrew D. (Inventor); Bluethmann, William J. (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Guo, Raymond (Inventor); Waligora, Thomas M. (Inventor); Akinyode, Akinjide Akinniyi (Inventor); Reed, Ryan M. (Inventor)

    2016-01-01

    A vehicle includes a chassis, a modular component, and a central operating system. The modular component is supported by the chassis. The central operating system includes a component control system, a primary master controller, and a secondary master controller. The component control system is configured for controlling the modular component. The primary and secondary master controllers are in operative communication with the component control system. The primary and secondary master controllers are configured to simultaneously transmit commands to the component control system. The component control system is configured to accept commands from the secondary master controller only when a fault occurs in the primary master controller.

  13. Active flow control for reduction of fluctuating aerodynamic forces of a blunt trailing edge profiled body

    Energy Technology Data Exchange (ETDEWEB)

    Naghib-Lahouti, Arash, E-mail: anaghibl@uwo.c [Boundary Layer Wind Tunnel Laboratory, University of Western Ontario, London, Ontario, N6A 5B9 (Canada); Hangan, Horia [Boundary Layer Wind Tunnel Laboratory, University of Western Ontario, London, Ontario, N6A 5B9 (Canada)

    2010-12-15

    Vortex shedding in the wake of two-dimensional bluff bodies is usually accompanied by three dimensional instabilities. These instabilities result in streamwise and vertical vorticity components which occur at a certain spanwise wavelength. The spanwise wavelength of the instabilities ({lambda}{sub Z}) depends on several parameters, including profile geometry and Reynolds number. The objective of the present work is to study the three dimensional wake instabilities for a blunt trailing edge profiled body, comprised of an elliptical leading edge and a rectangular trailing edge, and to manipulate these instabilities to control the aerodynamic forces. Results of numerical simulations of flow around the body at Re(d) = 400, 600, and 1000, as well as planar Laser Induced Fluorescence (LIF) flow visualizations at Re(d) = 600 and 1000 are analyzed to determine the wake vorticity structure and {lambda}{sub Z}. Based on the findings of these analyses, an active flow control mechanism for attenuation of the fluctuating aerodynamic forces on the body is proposed. The flow control mechanism is comprised of a series of trailing edge injection ports distributed across the span, with a spacing equal to {lambda}{sub Z}. Injection of a secondary flow leads to amplification of the three dimensional instabilities and disorganization of the von Karman vortex street. Numerical simulations indicate that the flow control mechanism can attenuate the fluctuating aerodynamic forces at lower Reynolds numbers (Re(d) = 400 and 600) where {lambda}{sub Z} is constant in time. However, the control mechanism loses its effectiveness at Re(d) = 1000, due to the temporal variations of {lambda}{sub Z}.

  14. Aerodynamic Database Development for Mars Smart Lander Vehicle Configurations

    Science.gov (United States)

    Bobskill, Glenn J.; Parikh, Paresh C.; Prabhu, Ramadas K.; Tyler, Erik D.

    2002-01-01

    An aerodynamic database has been generated for the Mars Smart Lander Shelf-All configuration using computational fluid dynamics (CFD) simulations. Three different CFD codes, USM3D and FELISA, based on unstructured grid technology and LAURA, an established and validated structured CFD code, were used. As part of this database development, the results for the Mars continuum were validated with experimental data and comparisons made where applicable. The validation of USM3D and LAURA with the Unitary experimental data, the use of intermediate LAURA check analyses, as well as the validation of FELISA with the Mach 6 CF(sub 4) experimental data provided a higher confidence in the ability for CFD to provide aerodynamic data in order to determine the static trim characteristics for longitudinal stability. The analyses of the noncontinuum regime showed the existence of multiple trim angles of attack that can be unstable or stable trim points. This information is needed to design guidance controller throughout the trajectory.

  15. Preview control of vehicle suspension system featuring MR shock absorber

    International Nuclear Information System (INIS)

    This paper presents control performance evaluation of optimal preview control algorithm for vehicle suspension featuring MR shock absorber. The optimal preview control algorithm has several advantages such as high control performance over that which is best for a non-preview system. In order to achieve this goal, a commercial MR shock absorber, Delphi MganerideTM, which is applicable to high class passenger vehicle, is adopted and its field-dependent damping force and dynamic responses are experimentally evaluated. Then the governing equation of motion for the full-vehicle model is established and integrated with the MR shock absorber. Subsequently, optimal controller with preview control algorithm is formulated and implemented for vibration suppression of the car body. Control performance of the preview controller is evaluated for the full-vehicle model under random road condition. In addition, the control performances depending on preview distances are evaluated.

  16. Aerodynamic Models for the Low Density Supersonic Decelerator (LDSD) Test Vehicles

    Science.gov (United States)

    Van Norman, John W.; Dyakonov, Artem; Schoenenberger, Mark; Davis, Jody; Muppidi, Suman; Tang, Chun; Bose, Deepak; Mobley, Brandon; Clark, Ian

    2016-01-01

    An overview of aerodynamic models for the Low Density Supersonic Decelerator (LDSD) Supersonic Flight Dynamics Test (SFDT) campaign test vehicle is presented, with comparisons to reconstructed flight data and discussion of model updates. The SFDT campaign objective is to test Supersonic Inflatable Aerodynamic Decelerator (SIAD) and large supersonic parachute technologies at high altitude Earth conditions relevant to entry, descent, and landing (EDL) at Mars. Nominal SIAD test conditions are attained by lifting a test vehicle (TV) to 36 km altitude with a helium balloon, then accelerating the TV to Mach 4 and 53 km altitude with a solid rocket motor. Test flights conducted in June of 2014 (SFDT-1) and 2015 (SFDT-2) each successfully delivered a 6 meter diameter decelerator (SIAD-R) to test conditions and several seconds of flight, and were successful in demonstrating the SFDT flight system concept and SIAD-R technology. Aerodynamic models and uncertainties developed for the SFDT campaign are presented, including the methods used to generate them and their implementation within an aerodynamic database (ADB) routine for flight simulations. Pre- and post-flight aerodynamic models are compared against reconstructed flight data and model changes based upon knowledge gained from the flights are discussed. The pre-flight powered phase model is shown to have a significant contribution to off-nominal SFDT trajectory lofting, while coast and SIAD phase models behaved much as predicted.

  17. Numerical and Experimental Investigations on the Aerodynamic Characteristic of Three Typical Passenger Vehicles

    Directory of Open Access Journals (Sweden)

    yiping wang

    2014-01-01

    Full Text Available The numerical simulation and wind tunnel experiment were employed to investigate the aerodynamic characteristics of three typical rear shapes: fastback, notchback and squareback. The object was to investigate the sensibility of aerodynamic characteristic to the rear shape, and provide more comprehensive experimental data as a reference to validate the numerical simulation. In the wind tunnel experiments, the aerodynamic six components of the three models with the yaw angles range from -15 and 15 were measured. The realizable k-ε model was employed to compute the aerodynamic drag, lift and surface pressure distribution at a zero yaw angle. In order to improve the calculation efficiency and accuracy, a hybrid Tetrahedron-Hexahedron-Pentahedral-Prism mesh strategy was used to discretize the computational domain. The computational results showed a good agreement with the experimental data and the results revealed that different rear shapes would induce very different aerodynamic characteristic, and it was difficult to determine the best shape. For example, the fastback would obtain very low aerodynamic drag, but it would induce positive lift which was not conducive to stability at high speed, and it also would induce bad crosswind stability. In order to reveal the internal connection between the aerodynamic drag and wake vortices, the turbulent kinetic, recirculation length, position of vortex core and velocity profile in the wake were investigated by numerical simulation and PIV experiment.

  18. On the aerodynamic redistribution of chondrite components in protoplanetary disks

    CERN Document Server

    Jacquet, Emmanuel; Fromang, Sébastien

    2012-01-01

    Despite being all roughly of solar composition, primitive meteorites (chondrites) present a diversity in their chemical, isotopic and petrographic properties, and in particular a first-order dichotomy between carbonaceous and non-carbonaceous chondrites. We investigate here analytically the dynamics of their components (chondrules, refractory inclusions, metal/sulfide and matrix grains) in protoplanetary disks prior to their incorporation in chondrite parent bodies. We find the dynamics of the solids, subject to gas drag, to be essentially controlled by the "gas-solid decoupling parameter" $S\\equiv \\textrm{St}/\\alpha$, the ratio of the dimensionless stopping time to the turbulence parameter. The decoupling of the solid particles relative to the gas is significant when $S$ exceeds unity. $S$ is expected to increase with time and heliocentric distance. On the basis of (i) abundance of refractory inclusions (ii) proportion of matrix (iii) lithophile element abundances and (iv) oxygen isotopic composition of chon...

  19. New propulsion components for electric vehicles

    Science.gov (United States)

    Secunde, R. R.

    1983-01-01

    Improved component technology is described. This includes electronically commutated permanent magnet motors of both drum and disk configurations, an unconventional brush commutated motor, ac induction motors, various controllers, transmissions and complete systems. One or more of these approaches to electric vehicle propulsion may eventually displace presently used controllers and brush commutated dc motors. Previously announced in STAR as N83-25982

  20. Body composition analysis: Cellular level modeling of body component ratios

    OpenAIRE

    Z. Wang; Heymsfield, S. B.; PI-SUNYER, F.X.; Gallagher, D.; PIERSON, R.N.

    2008-01-01

    During the past two decades, a major outgrowth of efforts by our research group at St. Luke’s-Roosevelt Hospital is the development of body composition models that include cellular level models, models based on body component ratios, total body potassium models, multi-component models, and resting energy expenditure-body composition models. This review summarizes these models with emphasis on component ratios that we believe are fundamental to understanding human body composition during growt...

  1. Aerodynamic Analysis of Flexible Flapping Wing Micro Aerial Vehicle Using Quasi-Steady Approach

    Science.gov (United States)

    Vijayakumar, Kolandapaiyan; Chandrasekhar, Uttam; Chandrashekhar, Nagaraj

    2016-04-01

    In recent times flexible flapping-wing aerodynamics has generated a great deal of interest and is the topic of contemporary research because of its potential application in micro aerial vehicles (MAVs). The prominent features of MAVs include low Reynolds Number, changing the camber of flapping wings, development of related mechanisms, study of the suitability airfoil shape selection and other parameters. Generally, low Reynolds Number is similar to that of an insect or a bird (103-105). The primary goal of this project work is to perform CFD analysis on flexible flapping wing MAVs in order to estimate the lift and drag by using engineering methods such as quasi-steady approach. From the wind tunnel data, 3-D deformation is obtained. For CFD analysis, two types of quasi-steady methods are considered. The first method is to slice the wing section chord-wise and span wise at multiple regions, frame by frame, and obtain the 2-D corrugated camber section for each frame. This 2-D corrugated camber is analysed using CFD techniques and all the individual 2-D corrugated camber results are summed up frame by frame, to obtain the total lift and drag for one wing beat. The second method is to consider the 3D wing in entirety and perform the CFD analysis to obtain the lift and drag for five wing beat.

  2. Dynamic stability of an aerodynamically efficient motorcycle

    Science.gov (United States)

    Sharma, Amrit; Limebeer, David J. N.

    2012-08-01

    Motorcycles exhibit two potentially dangerous oscillatory modes known as 'wobble' and 'weave'. The former is reminiscent of supermarket castor shimmy, while the latter is a low frequency 'fish-tailing' motion that involves a combination of rolling, yawing, steering and side-slipping motions. These unwanted dynamic features, which can occur when two-wheeled vehicles are operated at speed, have been studied extensively. The aim of this paper is to use mathematical analysis to identify important stability trends in the on-going design of a novel aerodynamically efficient motorcycle known as the ECOSSE Spirit ES1. A mathematical model of the ES1 is developed using a multi-body dynamics software package called VehicleSim [Anon, VehicleSim Lisp Reference Manual Version 1.0, Mechanical Simulation Corporation, 2008. Available at http://www.carsim.com]. This high-fidelity motorcycle model includes realistic tyre-road contact geometry, a comprehensive tyre model, tyre relaxation and a flexible frame. A parameter set representative of a modern high-performance machine and rider is used. Local stability is investigated via the eigenvalues of the linearised models that are associated with equilibrium points of interest. A comprehensive study of the effects of frame flexibilities, acceleration, aerodynamics and tyre variations is presented, and an optimal passive steering compensator is derived. It is shown that the traditional steering damper cannot be used to stabilise the ES1 over its entire operating speed range. A simple passive compensator, involving an inerter is proposed. Flexibility can be introduced deliberately into various chassis components to change the stability characteristics of the vehicle; the implications of this idea are studied.

  3. Large eddy simulation on the unsteady aerodynamic response of a road vehicle in transient crosswinds

    International Nuclear Information System (INIS)

    A large eddy simulation method based on a fully unstructured finite volume method was developed, and the unsteady aerodynamic response of a road vehicle subjected to transient crosswinds was investigated. First, the method was validated for a 1/20-scale wind-tunnel model in a static aerodynamic condition; this showed that the surface pressure distributions as well as the aerodynamic forces and moments were in good agreement with wind-tunnel data. Second, the method was applied to two transient crosswind situations: a sinusoidal perturbation representing the typical length scale of atmospheric turbulence and a stepwise crosswind velocity corresponding to wind gusts. Typical transient responses of the aerodynamic forces and moments such as phase shifting and undershooting or overshooting were observed, and their dependence on the frequency and amplitude of the input perturbation is discussed. Thus, the utility and validity of the large eddy simulation was demonstrated in the context that such transient aerodynamic forces are difficult to measure using a conventional wind tunnel.

  4. Aerodynamic Drag Reduction for A Generic Sport Utility Vehicle Using Rear Suction

    Directory of Open Access Journals (Sweden)

    Abdellah Ait Moussa

    2014-08-01

    Full Text Available The high demand for new and improved aerodynamic drag reduction devices has led to the invention of flow control mechanisms and continuous suction is a promising strategy that does not have major impact on vehicle geometry. The implementation of this technique on sport utility vehicles (SUV requires adequate choice of the size and location of the opening as well as the magnitude of the boundary suction velocity. In this paper we introduce a new methodology to identifying these parameters for maximum reduction in aerodynamic drag. The technique combines automatic modeling of the suction slit, computational fluid dynamics (CFD and a global search method using orthogonal arrays. It is shown that a properly designed suction mechanism can reduce drag by up to 9%..

  5. FY 2004 Annual Report: DOE Project on Heavy Vehicle Aerodynamic Drag

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, R C; Salari, K; Ortega, J; Castellucci, P; Eastwood, C; Whittaker, K; DeChant, L J; Roy, C J; Payne, J L; Hassan, B; Pointer, W D; Browand, F; Hammache, M; Hsu, T; Ross, J; Satran, D; Heineck, J T; Walker, S; Yaste, D; Englar, R; Leonard, A; Rubel, M; Chatelain, P

    2004-11-18

    The objective of this report is: (1) Provide guidance to industry in the reduction of aerodynamic drag of heavy truck vehicles; and (2) Establish a database of experimental, computational, and conceptual design information, and demonstrate potential of new drag-reduction devices. The approaches used were: (1) Develop and demonstrate the ability to simulate and analyze aerodynamic flow around heavy truck vehicles using existing and advanced computational fluid dynamics (CFD) tools; (2) Through an extensive experimental effort, generate an experimental data base for code validation; (3) Using experimental data base, validate computations; (4) Provide industry with design guidance and insight into flow phenomena from experiments and computations; and (5) Investigate aero devices (e.g., base flaps, tractor-trailer gap stabilizer, underbody skirts and wedges, blowing and acoustic devices), provide industry with conceptual designs of drag reducing devices, and demonstrate the full-scale fuel economy potential of these devices.

  6. Intermediate experimental vehicle, ESA program aerodynamics-aerothermodynamics key technologies for spacecraft design and successful flight

    Science.gov (United States)

    Dutheil, Sylvain; Pibarot, Julien; Tran, Dac; Vallee, Jean-Jacques; Tribot, Jean-Pierre

    2016-07-01

    With the aim of placing Europe among the world's space players in the strategic area of atmospheric re-entry, several studies on experimental vehicle concepts and improvements of critical re-entry technologies have paved the way for the flight of an experimental space craft. The successful flight of the Intermediate eXperimental Vehicle (IXV), under ESA's Future Launchers Preparatory Programme (FLPP), is definitively a significant step forward from the Atmospheric Reentry Demonstrator flight (1998), establishing Europe as a key player in this field. The IXV project objectives were the design, development, manufacture and ground and flight verification of an autonomous European lifting and aerodynamically controlled reentry system, which is highly flexible and maneuverable. The paper presents, the role of aerodynamics aerothermodynamics as part of the key technologies for designing an atmospheric re-entry spacecraft and securing a successful flight.

  7. July 2004 Working Group Meeting on Heavy Vehicle Aerodynamic Drag: Presentation, Summary of Comments, and Conclusions

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, R; Salari, K; Ortega, J; Castellucci, P; Eastwood, C; DeChant, L; Hassan, B; Browand, F; Arcas, D; Ross, J; Heineck, J; Storms, B; Walker, S; Leonard, A; Roy, C; Whitfield, D; Pointer, D; Sofu, T; Englar, R; Funk, R

    2004-08-17

    A Working Group Meeting on Heavy Vehicle Aerodynamic Drag was held in Portland, Oregon on July 1, 2004. The purpose of the meeting was to provide a summary of achievements, discuss pressing issues, present a general overview of future plans, and to provide a forum for dialogue with the Department of Energy (DOE) and industry representatives. The meeting was held in Portland, because the DOE Aero Team participated in an exclusive session on Heavy Truck Vehicle Aerodynamic Drag at the 34th AIAA Fluid Dynamics Conference and Exhibit in Portland on the morning of July 1st, just preceding our Working Group meeting. Even though the paper session was on the last day of the Conference, the Team presented to a full room of interested attendees.

  8. Propulsion System Airframe Integration Issues and Aerodynamic Database Development for the Hyper-X Flight Research Vehicle

    Science.gov (United States)

    Engelund, Walter C.; Holland, Scott D.; Cockrell, Charles E., Jr.; Bittner, Robert D.

    1999-01-01

    NASA's Hyper-X Research Vehicle will provide a unique opportunity to obtain data on an operational airframe integrated scramjet propulsion system at true flight conditions. The airframe integrated nature of the scramjet engine with the Hyper-X vehicle results in a strong coupling effect between the propulsion system operation and the airframe s basic aerodynamic characteristics. Comments on general airframe integrated scramjet propulsion system effects on vehicle aerodynamic performance, stability, and control are provided, followed by examples specific to the Hyper-X research vehicle. An overview is provided of the current activities associated with the development of the Hyper-X aerodynamic database, including wind tunnel test activities and parallel CFD analysis efforts. A brief summary of the Hyper-X aerodynamic characteristics is provided, including the direct and indirect effects of the airframe integrated scramjet propulsion system operation on the basic airframe stability and control characteristics.

  9. Design of Packaging for Microballoon Actuators and Feasibility of their Integration within Aerodynamic Flight Vehicle

    Directory of Open Access Journals (Sweden)

    A. Linga Murthy

    2009-09-01

    Full Text Available The microballoon actuators are used for the active flow control in turbulent boundary layer for aerodynamic control of flight vehicles. The packaging, interfacing, and integration of the microballoon actuators within the flight vehicle play a key role for functioning of the microballoon actuators during the flight conditions. This paper addresses the design and analysis of packaging and integration aspects and associated issues. The use of microballoon actuators on the control surfaces and nose cone of flight vehicles has the positive influence of delaying the flow separation from the aerodynamic surface. This results in enhancing aerodynamic effectiveness and lift as well as reduction of drag. A typical control surface is configured with eight microballoon actuators symmetric wrt the hinge line of the control surface and embedded within the control surface. Provision of the Pneumatic feed line system for inflation and deflation of the microballoons within the control surface has been made. The nose cone has been designed to have 32 such actuators at the circular periphery. The design is found to be completely feasible for the incorporation of microballoon actuators, both in the nose cone and in the control surface.Defence Science Journal, 2009, 59(5, pp.485-493, DOI:http://dx.doi.org/10.14429/dsj.59.1549

  10. A Study of Feature Combination for Vehicle Detection Based on Image Processing

    Directory of Open Access Journals (Sweden)

    Jon Arróspide

    2014-01-01

    Full Text Available Video analytics play a critical role in most recent traffic monitoring and driver assistance systems. In this context, the correct detection and classification of surrounding vehicles through image analysis has been the focus of extensive research in the last years. Most of the pieces of work reported for image-based vehicle verification make use of supervised classification approaches and resort to techniques, such as histograms of oriented gradients (HOG, principal component analysis (PCA, and Gabor filters, among others. Unfortunately, existing approaches are lacking in two respects: first, comparison between methods using a common body of work has not been addressed; second, no study of the combination potentiality of popular features for vehicle classification has been reported. In this study the performance of the different techniques is first reviewed and compared using a common public database. Then, the combination capabilities of these techniques are explored and a methodology is presented for the fusion of classifiers built upon them, taking into account also the vehicle pose. The study unveils the limitations of single-feature based classification and makes clear that fusion of classifiers is highly beneficial for vehicle verification.

  11. Experimental determinations of the aerodynamic drag for vehicles subjected to the ground effect

    Directory of Open Access Journals (Sweden)

    Bogdan TARUS

    2012-06-01

    Full Text Available A moving vehicle creates a flow of the surrounding air, continuous and compressible fluid. When the movement is at a constant speed, the air flow is not time dependent and the flow distribution lines are constant. In fact, however, a vehicle moves in an environment where the air itself is in a continuous motion. In addition, there are many side obstacles, such as passing objects, stationary vehicles, artwork, etc. All these factors affect the air flow along the vehicle. The shape and speed of the current lines are affected as compared with time. Based on these considerations, the aerodynamics of any ground vehicle is a non-stationary process. The study of non-stationary phenomena may be related to a steady state study using finite difference method, in which time is divided into finite intervals Δt, small enough so that during a specific period a phenomenon may be considered as stationary. If speeds involved are in subsonic regime, solving the equations of motion is simplified. We may consider therefore that the vehicle is moving at speed V1 in the air mass at rest, or both, the vehicle is at rest in a stream of air at speed V1 (this is the particular case of the wind tunnels. For speeds of up to Mach 0.5, the effect of compressibility of air does not influence at all or has very little influence on a flow. In this case, the air density may be considered constant. Also, the effect of viscosity can be neglected in most of the space occupied by the fluid. In order to illustrate the influence of the aerodynamic drag on a ground-effect vehicle we performed a test in the subsonic wind tunnel of the INCAS.

  12. Development of Pneumatic Aerodynamic Devices to Improve the Performance, Economics, and Safety of Heavy Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Robert J. Englar

    2000-06-19

    Under contract to the DOE Office of Heavy Vehicle Technologies, the Georgia Tech Research Institute (GTRI) is developing and evaluating pneumatic (blown) aerodynamic devices to improve the performance, economics, stability and safety of operation of Heavy Vehicles. The objective of this program is to apply the pneumatic aerodynamic aircraft technology previously developed and flight-tested by GTRI personnel to the design of an efficient blown tractor-trailer configuration. Recent experimental results obtained by GTRI using blowing have shown drag reductions of 35% on a streamlined automobile wind-tunnel model. Also measured were lift or down-load increases of 100-150% and the ability to control aerodynamic moments about all 3 axes without any moving control surfaces. Similar drag reductions yielded by blowing on bluff afterbody trailers in current US trucking fleet operations are anticipated to reduce yearly fuel consumption by more than 1.2 billion gallons, while even further reduction is possible using pneumatic lift to reduce tire rolling resistance. Conversely, increased drag and down force generated instantaneously by blowing can greatly increase braking characteristics and control in wet/icy weather due to effective ''weight'' increases on the tires. Safety is also enhanced by controlling side loads and moments caused on these Heavy Vehicles by winds, gusts and other vehicles passing. This may also help to eliminate the jack-knifing problem if caused by extreme wind side loads on the trailer. Lastly, reduction of the turbulent wake behind the trailer can reduce splash and spray patterns and rough air being experienced by following vehicles. To be presented by GTRI in this paper will be results developed during the early portion of this effort, including a preliminary systems study, CFD prediction of the blown flowfields, and design of the baseline conventional tractor-trailer model and the pneumatic wind-tunnel model.

  13. AERODYNAMIC STUDIES IN THE STATIC COMPONENTS OF A CENTRIFUGAL COMPRESSOR STAGE

    OpenAIRE

    K.SRINIVASA REDDY; G.V. Ramana Murty; K.V. Sharma

    2011-01-01

    Aerodynamic studies in the static components of a centrifugal compressor stage were conducted using the computational fluid dynamics solver FLUENT. For the simulation study, a typical centrifugal compressor stage geometry with a flow coefficient of 0.053 was chosen, The study is confined to the static components of the centrifugal compressor stage, i.e., the crossover bend (180° U-bend), a radial cascade of return channel vanes, and the exit ducting (90° L-turn). The aerodynamic performance i...

  14. Autonomous vehicle platforms from modular robotic components

    Science.gov (United States)

    Schonlau, William J.

    2004-09-01

    A brief survey of current autonomous vehicle (AV) projects is presented with intent to find common infrastructure or subsystems that can be configured from commercially available modular robotic components, thereby providing developers with greatly reduced timelines and costs and encouraging focus on the selected problem domain. The Modular Manipulator System (MMS) robotic system, based on single degree of freedom rotary and linear modules, is introduced and some approaches to autonomous vehicle configuration and deployment are examined. The modules may be configured to provide articulated suspensions for very rugged terrain and fall recovery, articulated sensors and tooling plus a limited capacity for self repair and self reconfiguration. The MMS on-board visually programmed control software (Model Manager) supports experimentation with novel physical configurations and behavior algorithms via real-time 3D graphics for operations simulation and provides useful subsystems for vision, learning and planning to host intelligent behavior.

  15. Development of Three-dimensional Grid-free Solver and its Applications to Multi-body Aerospace Vehicles

    Directory of Open Access Journals (Sweden)

    K. Anandhanarayanan

    2010-10-01

    Full Text Available Grid-free solver has the ability to solve complex multi-body industrial problems with minimal effort. Grid-free Euler solver has been applied to number of multi-body aerospace vehicles using Chimera clouds of points including flight vehicle with fin deflection, nose fairing separation of hypersonic launch vehicle. A preprocessor has been developed to generate connectivity for multi-bodies using overlapped grids. Surface transpiration boundary condition has been implemented to model aerodynamic damping and to impose the relative velocity of moving components. Dynamic derivatives are estimated with reasonable accuracy and less effort using the grid-free Euler solver with the transpiration boundary condition. Further, the grid-free Euler solver has been integrated with six-degrees of freedom (6-DOF equations of motion to form store separation dynamics suite which has been applied to obtain the trajectory of a rail launch air-to-air-missile from a complex fighter aircraft.Defence Science Journal, 2010, 60(6, pp.653-662, DOI:http://dx.doi.org/10.14429/dsj.60.583

  16. DOE Project on Heavy Vehicle Aerodynamic Drag FY 2005 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, R C; Salari, K; Ortega, J; Castellucci, P; Eastwood, C; Paschkewitz, J; Pointer, W D; DeChant, L J; Hassan, B; Browand, F; Radovich, C; Merzel, T; Plocher, D; Ross, J; Storms, B; Heineck, J T; Walker, S; Roy, C J

    2005-11-14

    Class 8 tractor-trailers consume 11-12% of the total US petroleum use. At high way speeds, 65% of the energy expenditure for a Class 8 truck is in overcoming aerodynamic drag. The project objective is to improve fuel economy of Class 8 tractor-trailers by providing guidance on methods of reducing drag by at least 25%. A 25% reduction in drag would present a 12% improvement in fuel economy at highway speeds, equivalent to about 130 midsize tanker ships per year. Specific goals include: (1) Provide guidance to industry in the reduction of aerodynamic drag of heavy truck vehicles; and (2) Establish a database of experimental, computational, and conceptual design information, and demonstrate the potential of new drag-reduction devices.

  17. Aerodynamic Interactions Between Wing and Body of a Model Insect in Forward Flight and Maneuvers

    Institute of Scientific and Technical Information of China (English)

    Bin Liang; Mao Sun

    2013-01-01

    The aerodynamic interactions between the body and the wings of a model insect in forward flight and maneuvers are studied using the method of numerically solving the Navier-Stokes equations over moving overset grids.Three cases are considered,including a complete insect,wing pair only and body only.By comparing the results of these cases,the interaction effect between the body and the wing pair can be identified.The changes in the force and moment coefficients of the wing pair due to the presence of the body are less than 4.5% of the mean vertical force coefficient of the model insect; the changes in the aerodynamic force coefficients of the body due to the presence of the wings are less than 5.0% of the mean vertical force coefficient of the model insect.The results of this paper indicate that in studying the aerodynamics and flight dynamics of a flapping insect in forward flight or maneuver,separately computing (or measuring) the aerodynamic forces and moments on the wing pair and on the body could be a good approximation.

  18. Design Of An Aerodynamic Measurement System For Unmanned Aerial Vehicle Airfoils

    Directory of Open Access Journals (Sweden)

    L. Velázquez-Araque

    2012-10-01

    Full Text Available This paper presents the design and validation of a measurement system for aerodynamic characteristics of unmanned aerial vehicles. An aerodynamic balance was designed in order to measure the lift, drag forces and pitching moment for different airfoils. During the design process, several aspects were analyzed in order to produce an efficient design, for instance the range of changes of the angle of attack with and a small increment and the versatility of being adapted to different type of airfoils, since it is a wire balance it was aligned and calibrated as well. Wind tunnel tests of a two dimensional NACA four digits family airfoil and four different modifications of this airfoil were performed to validate the aerodynamic measurement system. The modification of this airfoil was made in order to create a blowing outlet with the shape of a step on the suction surface. Therefore, four different locations along the cord line for this blowing outlet were analyzed. This analysis involved the aerodynamic performance which meant obtaining lift, drag and pitching moment coefficients curves as a function of the angle of attack experimentally for the situation where the engine of the aerial vehicle is turned off, called the no blowing condition, by means of wind tunnel tests. The experiments were performed in a closed circuit wind tunnel with an open test section. Finally, results of the wind tunnel tests were compared with numerical results obtained by means of computational fluid dynamics as well as with other experimental references and found to be in good agreement.

  19. Aerodynamic forces induced by controlled transitory flow on a body of revolution

    Science.gov (United States)

    Rinehart, Christopher S.

    The aerodynamic forces and moments on an axisymmetric body of revolution are controlled in a low-speed wind tunnel by induced local flow attachment. Control is effected by an array of aft-facing synthetic jets emanating from narrow, azimuthally segmented slots embedded within an axisymmetric backward facing step. The actuation results in a localized, segmented vectoring of the separated base flow along a rear Coanda surface and induced asymmetric aerodynamic forces and moments. The observed effects are investigated in both quasi-steady and transient states, with emphasis on parametric dependence. It is shown that the magnitude of the effected forces can be substantially increased by slight variations of the Coanda surface geometry. Force and velocity measurements are used to elucidate the mechanisms by which the synthetic jets produce asymmetric aerodynamic forces and moments, demonstrating a novel method to steer axisymmetric bodies during flight.

  20. Transitory Aerodynamic Forces on a Body of Revolution using Synthetic Jet Actuation

    Science.gov (United States)

    Rinehart, Christopher; McMichael, James; Glezer, Ari

    2002-11-01

    The aerodynamic forces and moments on axisymmetric bodies at subsonic speeds are controlled by exploiting local flow attachment using fluidic (synthetic jet) actuation and thereby altering the apparent aerodynamic shape of the surface. Control is effected upstream of the base of the body by an azimuthal array of individually-controlled, aft-facing synthetic jets emanating along an azimuthal Coanda surface. Actuation produces asymmetric aerodynamic forces and moments, with ratios of lift to average jet momentum approaching values typical of conventional jet-based circulation control on two-dimensional airfoils. Momentary forces are achieved using transient (pulsed) actuation and are accompanied by the formation and shedding of vorticity concentrations as a precursor to the turning of the outer flow into the wake region.

  1. Application of CAD/CAE class systems to aerodynamic analysis of electric race cars

    Science.gov (United States)

    Grabowski, L.; Baier, A.; Buchacz, A.; Majzner, M.; Sobek, M.

    2015-11-01

    Aerodynamics is one of the most important factors which influence on every aspect of a design of a car and car driving parameters. The biggest influence aerodynamics has on design of a shape of a race car body, especially when the main objective of the race is the longest distance driven in period of time, which can not be achieved without low energy consumption and low drag of a car. Designing shape of the vehicle body that must generate the lowest possible drag force, without compromising the other parameters of the drive. In the article entitled „Application of CAD/CAE class systems to aerodynamic analysis of electric race cars” are being presented problems solved by computer analysis of cars aerodynamics and free form modelling. Analysis have been subjected to existing race car of a Silesian Greenpower Race Team. On a basis of results of analysis of existence of Kammback aerodynamic effect innovative car body were modeled. Afterwards aerodynamic analysis were performed to verify existence of aerodynamic effect for innovative shape and to recognize aerodynamics parameters of the shape. Analysis results in the values of coefficients and aerodynamic drag forces. The resulting drag forces Fx, drag coefficients Cx(Cd) and aerodynamic factors Cx*A allowed to compare all of the shapes to each other. Pressure distribution, air velocities and streams courses were useful in determining aerodynamic features of analyzed shape. For aerodynamic tests was used Ansys Fluent CFD software. In a paper the ways of surface modeling with usage of Realize Shape module and classic surface modeling were presented. For shapes modeling Siemens NX 9.0 software was used. Obtained results were used to estimation of existing shapes and to make appropriate conclusions.

  2. Theoretical and Experimental Aerodynamic Analysis for High-Speed Ground Vehicles

    Science.gov (United States)

    Farhan, Ismail Haider

    Available from UMI in association with The British Library. This thesis investigates the air flow around a proposed geometry for a high-speed electromagnetic suspension (EMS) train. A numerical technique called the panel method has been applied to the representation of the body shape and the prediction of the potential flow and pressure distribution. Two computer programmes have been written, one for a single vehicle in the presence of the ground at different yaw angles, and the second for two-body problems, e.g. a train passing a railway station or a train passing the central part of another train. Two methods based on the momentum integral equations for three-dimensional boundary layer flow have been developed for use with the potential flow analysis; these predict the development of the three-dimensional turbulent boundary layer on the central section (for the analysis of crosswind conditions) and on the nose of the train. Extensive wind tunnel tests were performed on four models of the high-speed train to measure aerodynamic forces, moments and pressures to establish ground effect characteristics. Flow visualisation showed that the wake vortices were stronger and larger in the presence of a ground. At small yaw angles ground clearance had little effect, but as yaw increased, larger ground clearance led to substantial increase in lift and side force coefficients. The tests also identified the differences between a moving and a fixed ground plane. Data showed that the type of ground simulation was significant only in the separated region. A comparison of the results predicted using potential flow theory for an EMS train model and the corresponding results from wind tunnel tests indicated good agreement in regions where the flow is attached. The turbulent boundary layer calculations for the train in a crosswind condition showed that the momentum thickness along the crosswind surface distance co-ordinate increased slowly at the beginning of the development of the

  3. Experimental measurement of the aerodynamic charateristics of two-dimensional airfoils for an unmanned aerial vehicle

    Directory of Open Access Journals (Sweden)

    Nožička Jiří

    2012-04-01

    Full Text Available This paper is part of the development of an airfoil for an unmanned aerial vehicle (UAV with internal propulsion system; the investigation involves the analysis of the aerodynamic performance for the gliding condition of two-dimensional airfoil models which have been tested. This development is based on the modification of a selected airfoil from the NACA four digits family. The modification of this base airfoil was made in order to create a blowing outlet with the shape of a step on the suction surface since the UAV will have an internal propulsion system. This analysis involved obtaining the lift, drag and pitching moment coefficients experimentally for the situation where there is not flow through the blowing outlet, called the no blowing condition by means of wind tunnel tests. The methodology to obtain the forces experimentally was through an aerodynamic wire balance. Obtained results were compared with numerical results by means of computational fluid dynamics (CFD from references and found in very good agreement. Finally, a selection of the airfoil with the best aerodynamic performance is done and proposed for further analysis including the blowing condition.

  4. Experimental measurement of the aerodynamic charateristics of two-dimensional airfoils for an unmanned aerial vehicle

    Science.gov (United States)

    Velazquez, Luis; Nožička, Jiří; Vavřín, Jan

    2012-04-01

    This paper is part of the development of an airfoil for an unmanned aerial vehicle (UAV) with internal propulsion system; the investigation involves the analysis of the aerodynamic performance for the gliding condition of two-dimensional airfoil models which have been tested. This development is based on the modification of a selected airfoil from the NACA four digits family. The modification of this base airfoil was made in order to create a blowing outlet with the shape of a step on the suction surface since the UAV will have an internal propulsion system. This analysis involved obtaining the lift, drag and pitching moment coefficients experimentally for the situation where there is not flow through the blowing outlet, called the no blowing condition by means of wind tunnel tests. The methodology to obtain the forces experimentally was through an aerodynamic wire balance. Obtained results were compared with numerical results by means of computational fluid dynamics (CFD) from references and found in very good agreement. Finally, a selection of the airfoil with the best aerodynamic performance is done and proposed for further analysis including the blowing condition.

  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. CHARACTERISTICS OF WIND DEFLECTOR FOR REDUCING AERODYNAMIC DRAG OF VAN-BODY TRUCK

    Institute of Scientific and Technical Information of China (English)

    Du Guang-sheng; Lei Li; Zhou Lian-di

    2003-01-01

    In this paper, the differences in the characteristics of airflow around the van-body truck and of the aerodynamic drag, which were caused by the installation of a wind deflector, were studied by experimentally and numerically. The results show that after the installation of the deflector, the airflow around the top and bottom of the truck becoms smooth, the intensity of tail-vortex is weakened and its contribution area lessened. It also indicates that the aerodynamic characteristics of the airflow are changed distinctly and the aerodynamic drag is reduced considerably. The effect of the thin-wall deflector is better than the solid one in decreasing the drag. It is also concluded that proper design of the gap between the deflector bottom and the top of the driver cab can enhance the effect of the deflector in reducing drag.

  7. Vibration Damping Via Acoustic Treatment Attached To Vehicle Body Panels

    Science.gov (United States)

    Gambino, Carlo

    Currently, in the automotive industry, the control of noise and vibration is the subject of much research, oriented towards the creation of innovative solutions to improve the comfort of the vehicle and to reduce its cost and weight. This thesis fits into this particular framework, as it aims to investigate the possibility of integrating the functions of sound absorptioninsulation and vibration damping in a unique component. At present the bituminous viscoelastic treatments, which are bonded to the car body panels, take charge of the vibration damping, while the sound absorption and insulation is obtained by means of the poroacoustic treatments. The solution proposed here consists of employing porous materials to perform both these functions, thus allowing the partial or complete removal of the viscoelastic damping treatments from the car body. This should decrease the weight of the vehicle, reducing fuel consumption and emissions, and it might also benefit production costs.

  8. Modeling vehicle emissions in different types of Chinese cities: Importance of vehicle fleet and local features

    International Nuclear Information System (INIS)

    We propose a method to simulate vehicle emissions in Chinese cities of different sizes and development stages. Twenty two cities are examined in this study. The target year is 2007. Among the cities, the vehicle emission factors were remarkably different (the highest is 50-90% higher than the lowest) owing to their distinct local features and vehicle technology levels, and the major contributors to total vehicle emissions were also different. A substantial increase in vehicle emissions is foreseeable unless stronger measures are implemented because the benefit of current policies can be quickly offset by the vehicle growth. Major efforts should be focused on all cities, especially developing cities where the requirements are lenient. This work aims a better understanding of vehicle emissions in all types of Chinese cities. The proposed method could benefit national emission inventory studies in improving accuracy and help in designing national and local policies for vehicle emission control. - Highlights: → We examine vehicle emissions in 22 Chinese cities of different types and locations. → Vehicle emission factors of the cities differ by 50-90% due to distinct local features. → Each vehicle type contributes differently to total emissions among the cities. → A substantial increase in vehicle emissions in most Chinese cities is foreseeable. → City-specific fleet and local features are important in research and policy making. - Vehicle emission characteristics of Chinese cities are remarkably different, and local features need to be taken into account in vehicle emission studies and control strategy.

  9. Computational Study of a McDonnell Douglas Single-Stage-to-Orbit Vehicle Concept for Aerodynamic Analysis

    Science.gov (United States)

    Prabhu, Ramadas K.

    1996-01-01

    This paper presents the results of a computational flow analysis of the McDonnell Douglas single-stage-to-orbit vehicle concept designated as the 24U. This study was made to determine the aerodynamic characteristics of the vehicle with and without body flaps over an angle of attack range of 20-40 deg. Computations were made at a flight Mach number of 20 at 200,000 ft. altitude with equilibrium air, and a Mach number of 6 with CF4 gas. The software package FELISA (Finite Element Langley imperial College Sawansea Ames) was used for all the computations. The FELISA software consists of unstructured surface and volume grid generators, and inviscid flow solvers with (1) perfect gas option for subsonic, transonic, and low supersonic speeds, and (2) perfect gas, equilibrium air, and CF4 options for hypersonic speeds. The hypersonic flow solvers with equilibrium air and CF4 options were used in the present studies. Results are compared with other computational results and hypersonic CF4 tunnel test data.

  10. Lateral dynamic features of a railway vehicle

    DEFF Research Database (Denmark)

    Gao, Xue-jun; True, Hans; Li, Ying-hui

    2016-01-01

    by varying the speed and using the resultant bifurcation diagram' method. It is found that multiple solution branches exist and they can lead to more steady states in the dynamic behaviour of the railway vehicle. The coexistence of multiple steady states can lead to jumps in the amplitude of oscillations......, resulting in problems for safe operation of the vehicle. Therefore, it should be avoided in everyday operation. Furthermore, the creation of multiple solution branches suggests that the critical speed of a vehicle should be determined from a comprehensive analysis of the various kinds of possible...

  11. Flow visualization using the laser light sheet method in vehicle aerodynamics and combustion chamber engineering

    Science.gov (United States)

    Hentschel, Werner

    Laser light sheet flow visualization is applied in the automobile industry with a view to the reduction of air resistance. Using high power lasers a plane is cut out of the 3-D flow field and the course of flow in the plane is analyzed. In vehicle aerodynamics the flow phenomena are mainly visualized with smoke in the tail region of automobiles and in the wake, in planes parallel as well as perpendicular to the flow direction. For the investigation of flow phenomena in the combustion chamber of Otto and Diesel engines, the laser light sheet method is used on a series motor with optical access, the so-called flow motor. Typical results and requirements for future automated evaluation methods are discussed.

  12. Multi-Mission Earth Entry Vehicle: Aerodynamic and Aerothermal Analysis of Trajectory Environments

    Science.gov (United States)

    Trumble, Kerry; Dyakonov, Artem; Fuller, John

    2010-01-01

    Multi-mission Earth Entry Vehicle (MMEEV) is designed to deliver small payloads from space to Earth's surface by flying an uncontrolled ballistic entry, which ends with ground impact. The included range of entry velocities is from 10 to 16 km/s. The range of ballistic coefficients is from 41.94 to 128.74 kg/m2, which insures a low subsonic terminal velocity on the order of 50 m/sec. The range of entry flight path angles, considered in this analysis is from -5 to -25 degrees. The assessment and parametric characterization of aeroheating and aerodynamic performance of the capsule during entry is the subject of this paper.

  13. Catalog of components for electric and hybrid vehicle propulsion systems

    Science.gov (United States)

    Eissler, H. C.

    1981-01-01

    This catalog of commercially available electric and hybrid vehicle propulsion system components is intended for designers and builders of these vehicles and contains 50 categories of components. These categories include those components used between the battery terminals and the output axle hub, as well as some auxiliary equipment. An index of the components and a listing of the suppliers and their addresses and phone numbers are included.

  14. Low-speed Aerodynamic Investigations of a Hybrid Wing Body Configuration

    Science.gov (United States)

    Vicroy, Dan D.; Gatlin, Gregory M.; Jenkins, Luther N.; Murphy, Patrick C.; Carter, Melissa B.

    2014-01-01

    Two low-speed static wind tunnel tests and a water tunnel static and dynamic forced-motion test have been conducted on a hybrid wing-body (HWB) twinjet configuration. These tests, in addition to computational fluid dynamics (CFD) analysis, have provided a comprehensive dataset of the low-speed aerodynamic characteristics of this nonproprietary configuration. In addition to force and moment measurements, the tests included surface pressures, flow visualization, and off-body particle image velocimetry measurements. This paper will summarize the results of these tests and highlight the data that is available for code comparison or additional analysis.

  15. Direct measurements of controlled aerodynamic forces on a wire-suspended axisymmetric body

    Science.gov (United States)

    Abramson, Philip; Vukasinovic, Bojan; Glezer, Ari

    2011-06-01

    A novel in-line miniature force transducer is developed for direct measurements of the net aerodynamic forces and moments on a bluff body. The force transducers are integrated into each of the eight mounting wires that are utilized for suspension of an axisymmetric model in a wind tunnel having minimal wake interference. The aerodynamic forces and moments on the model are altered by induced active local attachment of the separated base flow. Fluidic control is effected by an array of four integrated aft-facing synthetic jet actuators that emanate from narrow, azimuthally segmented slots, equally distributed around the perimeter of the circular tail end. The jet orifices are embedded within a small backward-facing step that extends into a Coanda surface. The altered flow dynamics associated with both quasi-steady and transitory asymmetric activation of the flow control effect is characterized by direct force and PIV measurements.

  16. AERODYNAMIC STUDIES IN THE STATIC COMPONENTS OF A CENTRIFUGAL COMPRESSOR STAGE

    Directory of Open Access Journals (Sweden)

    K. Srinivasa Reddy

    2011-12-01

    Full Text Available Aerodynamic studies in the static components of a centrifugal compressor stage were conducted using the computational fluid dynamics solver FLUENT. For the simulation study, a typical centrifugal compressor stage geometry with a flow coefficient of 0.053 was chosen, The study is confined to the static components of the centrifugal compressor stage, i.e., the crossover bend (180° U-bend, a radial cascade of return channel vanes, and the exit ducting (90° L-turn. The aerodynamic performance is reported in terms of total pressure loss coefficient, static pressure recovery coefficient, return channel vane surface static pressure distribution, and stage exit swirl angle distribution. The simulated flow through the static components covered five different operating conditions of the actual centrifugal compressor stage: the design point with 100% flow rate, and the off-design operating conditions with 70%, 80%, 110%, and 120% flow rates. The standard k-ε model was used with standard wall functions to predict the turbulence. A minimum total pressure loss coefficient was observed near 80% flow rate when the average flow angle at the U-bend inlet was 24°. Better static pressure recovery was observed with 70%, 80%, and 100% flow rates. The swirl angle distribution at the stage exit was recognized as satisfactory.

  17. Aerodynamic Design of Heavy Vehicles Reporting Period January 15, 2004 through April 15, 2004

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, A; Chatelain, P; Heineck, J; Browand, F; Mehta, R; Ortega, J; Salari, K; Storms, B; Brown, J; DeChant, L; Rubel, M; Ross, J; Hammache, M; Pointer, D; Roy, C; Hassan, B; Arcas, D; Hsu, T; Payne, J; Walker, S; Castellucci, P; McCallen, R

    2004-04-13

    Listed are summaries of the activities and accomplishments during this second-quarter reporting period for each of the consortium participants. The following are some highlights for this reporting period: (1) Experiments and computations guide conceptual designs for reduction of drag due to tractor-trailer gap flow (splitter plate), trailer underbody (wedges), and base drag (base-flap add-ons). (2) Steady and unsteady RANS simulations for the GTS geometry are being finalized for development of clear modeling guidelines with RANS. (3) Full geometry and tunnel simulations on the GCM geometry are underway. (4) CRADA with PACCAR is supporting computational parametric study to determine predictive need to include wind tunnel geometry as limits of computational domain. (5) Road and track test options are being investigated. All is ready for field testing of base-flaps at Crows Landing in California in collaboration with Partners in Advanced Transportation Highways (PATH). In addition, MAKA of Canada is providing the device and Wabash is providing a new trailer. (6) Apparatus to investigate tire splash and spray has been designed and is under construction. Michelin has offered tires with customized threads for this study. (7) Vortex methods have improved techniques for the treatment of vorticity near surfaces and spinning geometries like rotating tires. (8) Wind tunnel experiments on model rail cars demonstrate that empty coal cars exhibit substantial aerodynamic drag compared to full coal cars, indicating that significant fuel savings could be obtained by reducing the drag of empty coal cars. (9) Papers are being prepared for an exclusive conference session on the Heavy Vehicle DOE Aerodynamic Drag Project at the 34th AIAA Fluid Dynamics Conference in Portland, Oregon, June 28-July 1, 2004.

  18. 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.

  19. REUSE OF AUTOMOTIVE COMPONENTS FROM DISMANTLED END OF LIFE VEHICLES

    Directory of Open Access Journals (Sweden)

    Piotr NOWAKOWSKI

    2013-12-01

    Full Text Available The problem of recycling end of life automotive vehicles is serious worldwide. It is one of the most important streams of waste in developed countries. It has big importance as recycling potential of raw materials content in automotive vehicles is valuable. Different parts and assemblies after dismantling can also be reused in vehicles where replacement of specific component is necessary. Reuse of the components should be taken into consideration in selecting the vehicles dismantling strategy. It also complies with European Union policy concerning end of life vehicles (ELV. In the paper it is presented systematic approach to dismantling strategies including disassembly oriented on further reuse of components. It is focused on decision making and possible benefits calculation from economic and environmental point of view.

  20. TAD- THEORETICAL AERODYNAMICS PROGRAM

    Science.gov (United States)

    Barrowman, J.

    1994-01-01

    This theoretical aerodynamics program, TAD, was developed to predict the aerodynamic characteristics of vehicles with sounding rocket configurations. These slender, axisymmetric finned vehicle configurations have a wide range of aeronautical applications from rockets to high speed armament. Over a given range of Mach numbers, TAD will compute the normal force coefficient derivative, the center-of-pressure, the roll forcing moment coefficient derivative, the roll damping moment coefficient derivative, and the pitch damping moment coefficient derivative of a sounding rocket configured vehicle. The vehicle may consist of a sharp pointed nose of cone or tangent ogive shape, up to nine other body divisions of conical shoulder, conical boattail, or circular cylinder shape, and fins of trapezoid planform shape with constant cross section and either three or four fins per fin set. The characteristics computed by TAD have been shown to be accurate to within ten percent of experimental data in the supersonic region. The TAD program calculates the characteristics of separate portions of the vehicle, calculates the interference between separate portions of the vehicle, and then combines the results to form a total vehicle solution. Also, TAD can be used to calculate the characteristics of the body or fins separately as an aid in the design process. Input to the TAD program consists of simple descriptions of the body and fin geometries and the Mach range of interest. Output includes the aerodynamic characteristics of the total vehicle, or user-selected portions, at specified points over the mach range. The TAD program is written in FORTRAN IV for batch execution and has been implemented on an IBM 360 computer with a central memory requirement of approximately 123K of 8 bit bytes. The TAD program was originally developed in 1967 and last updated in 1972.

  1. Aerodynamic Interference between Oscillating Lifting Surfaces and Fuselage Part 5: A Panel Method for Non-Lifting Bodies

    Directory of Open Access Journals (Sweden)

    Valentin Adrian Jean BUTOESCU

    2015-09-01

    Full Text Available In the fifth article of our series we will deal with the calculation of the unsteady aerodynamic forces on non-lifting bodies. We present here a contribution to the problem of the flow about non-lifting bodies. It is a panel method available for subsonic unsteady flow. The method will be used further to the unsteady body-body and wing-body interference problems.

  2. MODELLING OF EROSION EFFECTS ON COATINGS OF MILITARY VEHICLE COMPONENTS

    OpenAIRE

    Stodola, Petr; Jamrichova, Zuzana; Stodola, Jiri

    2012-01-01

    Military and flying machines (vehicles, aircraft, etc.) operate in extreme conditions and require appropriate measurements to improve the durability of all systems and materials in their subsystems. Protective coatings usually perform this function with great success. One of the most pressing needs for change military vehicles is the development of high performance coatings for erosion protection of military machine components (turbine, engine, compressor, turbocharger, intercooler components...

  3. A New Application of Multi- Body System Dynamics in Vehicle- Road Interaction Simulation

    Institute of Scientific and Technical Information of China (English)

    Ren Wei-qun; Zhang Yun-qing; Jin Guo-dong

    2003-01-01

    In vehicle-road interaction simulation, multi-body system (MBS) dynamics as well as the corresponding software ADAMS has been employed to model the nonlinear vehicle in more detail. The simulation method has been vali-dated by the test data, and been compared to the former sim-ple models. This method can be used for estimating the effects of dynamic tire forces and other vehicle features on road damage so that the "road- friend liness" can be assessed in vehicle design process.

  4. Launch vehicle payload adapter design with vibration isolation features

    Science.gov (United States)

    Thomas, Gareth R.; Fadick, Cynthia M.; Fram, Bryan J.

    2005-05-01

    Payloads, such as satellites or spacecraft, which are mounted on launch vehicles, are subject to severe vibrations during flight. These vibrations are induced by multiple sources that occur between liftoff and the instant of final separation from the launch vehicle. A direct result of the severe vibrations is that fatigue damage and failure can be incurred by sensitive payload components. For this reason a payload adapter has been designed with special emphasis on its vibration isolation characteristics. The design consists of an annular plate that has top and bottom face sheets separated by radial ribs and close-out rings. These components are manufactured from graphite epoxy composites to ensure a high stiffness to weight ratio. The design is tuned to keep the frequency of the axial mode of vibration of the payload on the flexibility of the adapter to a low value. This is the main strategy adopted for isolating the payload from damaging vibrations in the intermediate to higher frequency range (45Hz-200Hz). A design challenge for this type of adapter is to keep the pitch frequency of the payload above a critical value in order to avoid dynamic interactions with the launch vehicle control system. This high frequency requirement conflicts with the low axial mode frequency requirement and this problem is overcome by innovative tuning of the directional stiffnesses of the composite parts. A second design strategy that is utilized to achieve good isolation characteristics is the use of constrained layer damping. This feature is particularly effective at keeping the responses to a minimum for one of the most important dynamic loading mechanisms. This mechanism consists of the almost-tonal vibratory load associated with the resonant burn condition present in any stage powered by a solid rocket motor. The frequency of such a load typically falls in the 45-75Hz range and this phenomenon drives the low frequency design of the adapter. Detailed finite element analysis is

  5. Aerodynamics Research Revolutionizes Truck Design

    Science.gov (United States)

    2008-01-01

    During the 1970s and 1980s, researchers at Dryden Flight Research Center conducted numerous tests to refine the shape of trucks to reduce aerodynamic drag and improved efficiency. During the 1980s and 1990s, a team based at Langley Research Center explored controlling drag and the flow of air around a moving body. Aeroserve Technologies Ltd., of Ottawa, Canada, with its subsidiary, Airtab LLC, in Loveland, Colorado, applied the research from Dryden and Langley to the development of the Airtab vortex generator. Airtabs create two counter-rotating vortices to reduce wind resistance and aerodynamic drag of trucks, trailers, recreational vehicles, and many other vehicles.

  6. Numerical Investigation of Bending-Body Projectile Aerodynamics for Maneuver Control

    Science.gov (United States)

    Youn, Eric; Silton, Sidra

    2015-11-01

    Precision munitions are an active area of research for the U.S. Army. Canard-control actuators have historically been the primary mechanism used to maneuver fin-stabilized, gun-launched munitions. Canards are small, fin-like control surfaces mounted at the forward section of the munition to provide the pitching moment necessary to rotate the body in the freestream flow. The additional lift force due to the rotated body and the canards then alters the flight path toward the intended target. As velocity and maneuverability requirements continue to increase, investigation of other maneuver mechanisms becomes necessary. One option for a projectile with a large length-to-diameter ratio (L/D) is a bending-body design, which imparts a curvature to the projectile body along its axis. This investigation uses full Navier-Stokes computational fluid dynamics simulations to evaluate the effectiveness of an 8-degree bent nose tip on an 8-degree bent forward section of an L/D =10 projectile. The aerodynamic control effectiveness of the bending-body concept is compared to that of a standard L/D =10 straight-body projectile as well as that of the same projectile with traditional canards. All simulations were performed at supersonic velocities between Mach 2-4.

  7. Transition aerodynamics for 20-percent-scale VTOL unmanned aerial vehicle

    Science.gov (United States)

    Kjerstad, Kevin J.; Paulson, John W., Jr.

    1993-01-01

    An investigation was conducted in the Langley 14- by 22-Foot Subsonic Tunnel to establish a transition data base for an unmanned aerial vehicle utilizing a powered-lift ejector system and to evaluate alterations to the ejector system for improved vehicle performance. The model used in this investigation was a 20-percent-scale, blended-body, arrow-wing configuration with integrated twin rectangular ejectors. The test was conducted from hover through transition conditions with variations in angle of attack, angle of sideslip, free-stream dynamic pressure, nozzle pressure ratio, and model ground height. Force and moment data along with extensive surface pressure data were obtained. A laser velocimeter technique for measuring inlet flow velocities was demonstrated at a single flow condition, and also a low order panel method was successfully used to numerically simulate the ejector inlet flow.

  8. Fuel-Efficient Road Vehicle Non-Engine Components

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    The need to address global energy issues, i.e. energy security and climate change, is more urgent than ever. Road vehicles dominate global oil consumption and are one of the fastest growing energy end-uses. This paper studies policies and measures to improve on-road fuel efficiency of vehicles by focusing on energy efficiency of automobile components not generally considered in official fuel efficiency test, namely tyres, cooling technologies and lightings. In this paper, current policies and industry activities on these components are reviewed, fuel saving potential by the components analysed and possible policies to realise the potential recommended.

  9. 地铁车辆吸能装置耐碰撞性分析%Analysis of Crashworthiness of Energy-Absorbing Component in the Metro Vehicle Car-body

    Institute of Scientific and Technical Information of China (English)

    韩增盛; 马松花

    2012-01-01

    吸能装置是确保地铁列车具有良好耐碰撞性能的一种重要部件.为实现地铁车辆吸能装置的结构优化,采用有限元分析软件ANSYS/LS-DYNA对不同厚度、不同横截面形状的薄壁结构碰撞性进行了仿真分析,分析结果表明,吸能装置的性能与其横截面的形状、壁厚的选择紧密相关.条件相同时,吸能装置的吸能能力与壁厚成正比,但壁厚增加时,界面力也随之增大,在吸能结构的设计中,需综合考虑.以地铁头车为研究对象,对安装了吸能装置的地铁头车进行了碰撞仿真,得到车体吸能装置碰撞过程变形情况和碰撞能量-时间历程,结果表明该结构吸能装置具有良好的吸能特性.%Energy-absorbing structure is an important component to ensure that the metro train has a good crashworthiness. In order to realize the optimization of the energy-absorbing structure, finite element analysis software ANSYS/LS-DYNA is used to simulate the crash performance of thin-wall structures of various thickness, cross-section. The results show that the performance of energy-absorbing component is closely related to cross section and thickness. The same conditions, absorption capability of energy-absorbing component is proportional to thickness, however,interface force increases with the increase of thickness,therefore,in the design of energy-absorbing component,it is necessary to consider it fully. Take the metro vehicle for example,one metro vehicle equipped with the energy absorption component is put up to simulate the collision procedure, and the deformation of the energy-absorbing component and the collision energy-time course are obtained, the results show that this energy-absorbing component has good energy absorption performance.

  10. Aerodynamic force generation, performance and control of body orientation during gliding in sugar gliders (Petaurus breviceps).

    Science.gov (United States)

    Bishop, Kristin L

    2007-08-01

    Gliding has often been discussed in the literature as a possible precursor to powered flight in vertebrates, but few studies exist on the mechanics of gliding in living animals. In this study I analyzed the 3D kinematics of sugar gliders (Petaurus breviceps) during short glides in an enclosed space. Short segments of the glide were captured on video, and the positions of marked anatomical landmarks were used to compute linear distances and angles, as well as whole body velocities and accelerations. From the whole body accelerations I estimated the aerodynamic forces generated by the animals. I computed the correlations between movements of the limbs and body rotations to examine the control of orientation during flight. Finally, I compared these results to those of my earlier study on the similarly sized and distantly related southern flying squirrel (Glaucomys volans). The sugar gliders in this study accelerated downward slightly (1.0+/-0.5 m s(-2)), and also accelerated forward (2.1+/-0.6 m s(-2)) in all but one trial, indicating that the body weight was not fully supported by aerodynamic forces and that some of the lift produced forward acceleration rather than just balancing body weight. The gliders used high angles of attack (44.15+/-3.12 degrees ), far higher than the angles at which airplane wings would stall, yet generated higher lift coefficients (1.48+/-0.18) than would be expected for a stalled wing. Movements of the limbs were strongly correlated with body rotations, suggesting that sugar gliders make extensive use of limb movements to control their orientation during gliding flight. In addition, among individuals, different limb movements were associated with a given body rotation, suggesting that individual variation exists in the control of body rotations. Under similar conditions, flying squirrels generated higher lift coefficients and lower drag coefficients than sugar gliders, yet had only marginally shallower glides. Flying squirrels have a

  11. Error Estimate of the Ares I Vehicle Longitudinal Aerodynamic Characteristics Based on Turbulent Navier-Stokes Analysis

    Science.gov (United States)

    Abdol-Hamid, Khaled S.; Ghaffari, Farhad

    2011-01-01

    Numerical predictions of the longitudinal aerodynamic characteristics for the Ares I class of vehicles, along with the associated error estimate derived from an iterative convergence grid refinement, are presented. Computational results are based on the unstructured grid, Reynolds-averaged Navier-Stokes flow solver USM3D, with an assumption that the flow is fully turbulent over the entire vehicle. This effort was designed to complement the prior computational activities conducted over the past five years in support of the Ares I Project with the emphasis on the vehicle s last design cycle designated as the A106 configuration. Due to a lack of flight data for this particular design s outer mold line, the initial vehicle s aerodynamic predictions and the associated error estimates were first assessed and validated against the available experimental data at representative wind tunnel flow conditions pertinent to the ascent phase of the trajectory without including any propulsion effects. Subsequently, the established procedures were then applied to obtain the longitudinal aerodynamic predictions at the selected flight flow conditions. Sample computed results and the correlations with the experimental measurements are presented. In addition, the present analysis includes the relevant data to highlight the balance between the prediction accuracy against the grid size and, thus, the corresponding computer resource requirements for the computations at both wind tunnel and flight flow conditions. NOTE: Some details have been removed from selected plots and figures in compliance with the sensitive but unclassified (SBU) restrictions. However, the content still conveys the merits of the technical approach and the relevant results.

  12. 10 CFR Appendix D to Part 110 - Illustrative List of Aerodynamic Enrichment Plant Equipment and Components Under NRC Export...

    Science.gov (United States)

    2010-01-01

    ... Equipment and Components Under NRC Export Licensing Authority D Appendix D to Part 110 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) EXPORT AND IMPORT OF NUCLEAR EQUIPMENT AND MATERIAL Pt. 110, App. D... Export Licensing Authority Note—In aerodynamic enrichment processes, a mixture of gaseous UF6 and...

  13. EFFECT OF BODY SHAPE ON THE AERODYNAMICS OF PROJECTILES AT SUPERSONIC SPEEDS

    Directory of Open Access Journals (Sweden)

    ABDULKAREEM SH. MAHDI

    2008-12-01

    Full Text Available An investigation has been made to predict the effects of forebody and afterbody shapes on the aerodynamic characteristics of several projectile bodies at supersonic speeds using analytical methods combined with semi-empirical design curves. The considered projectile bodies had a length-to-diameter ratio of 6.67 and included three variations of forebody shape and three variations of afterbody shape. The results, which are verified by comparison with available experimental data, indicated that the lowest drag was achieved with a cone-cylinder at the considered Mach number range. It is also shown that the drag can be reduced by boattailing the afterbody. The centre-of-pressure assumed a slightly rearward location for the ogive-cylinder configuration when compared to the configuration with boattailed afterbody where it was the most forward. With the exception of the boattailed afterbody, all the bodies indicated inherent static stability above Mach number 2 for a centre-of-gravity location at about 40% from the body nose.

  14. September 2002 Working Group Meeting on Heavy Vehicle Aerodynamic Drag: Presentations and Summary of Comments and Conclusions

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, R

    2002-09-01

    A Working Group Meeting on Heavy Vehicle Aerodynamic Drag was held at NASA Ames Research Center on September 23, 2002. The purpose of the meeting was to present and discuss technical details on the experimental and computational work in progress and future project plans. Representatives from the Department of Energy (DOE)/Office of Energy Efficiency and Renewable Energy/Office of FreedomCAR & Vehicle Technologies, Lawrence Livermore National Laboratory (LLNL), Sandia National Laboratories (SNL), NASA Ames Research Center (NASA), University of Southern California (USC), California Institute of Technology (Caltech), Georgia Tech Research Institute (GTRI), Argonne National Laboratory (ANL), Freightliner, and Portland State University participated in the meeting. This report contains the technical presentations (viewgraphs) delivered at the Meeting, briefly summarizes the comments and conclusions, and outlines the future action items. The meeting began with an introduction by the Project Lead Rose McCallen of LLNL, where she emphasized that the world energy consumption is predicted to relatively soon exceed the available resources (i.e., fossil, hydro, non-breeder fission). This short fall is predicted to begin around the year 2050. Minimizing vehicle aerodynamic drag will significantly reduce our Nation's dependence on foreign oil resources and help with our world-wide fuel shortage. Rose also mentioned that educating the populace and researchers as to our world energy issues is important and that our upcoming United Engineering Foundation (UEF) Conference on ''The Aerodynamics of Heavy Vehicles: Trucks, Busses, and Trains'' was one way our DOE Consortium was doing this. Mentioned were the efforts of Fred Browand from USC in organizing and attracting internationally recognized speakers to the Conference. Rose followed with an overview of the DOE project goals, deliverables, and FY03 activities. The viewgraphs are attached at the end of this

  15. Detecting feature interactions: how many components do we need?

    OpenAIRE

    Calder, M.; Miller, A.

    2004-01-01

    Features are a structuring mechanism for additional functionality, usually in response to changing requirements. When several features are invoked at the same time, by the same, or different components, the features may not interwork. This is known as feature interaction. We employ a property-based approach to feature interaction detection: this involves checking the validity (or not) of a temporal property against a given system model. We use the logic LTL for temporal properties and the mod...

  16. Feature Comparison in Structural Health Monitoring of a Vehicle Crane

    Directory of Open Access Journals (Sweden)

    J. Kullaa

    2008-01-01

    Full Text Available Vibration-based structural health monitoring of a vehicle crane was studied. The performance of different features to detect damage was investigated after eliminating the normal operational variations using factor analysis. Using eight accelerometers, ten AR parameters from each record were identified for damage detection. Also transmissibilities between sensors were estimated. Damage was introduced with additional masses at different locations of the structure. All damage cases could be detected from either features using control charts, but transmissibilities proved to be more sensitive to damage than the AR coefficients.

  17. Numerical assessment of the impact of vehicle body stiffness on handling performance

    OpenAIRE

    Coox, Laurens; Vivet, Mathijs; Tamarozzi, Tommaso; Geluk, Theo; Cremers, Luc; Desmet, Wim

    2012-01-01

    This paper investigates the problem of how to use Computer-Aided Engineering (CAE) tools to properly assess the influence of vehicle body stiffness on handling performance. One of the challenges in this context is related to the accuracy of the Body-In-White (BIW) model. The amount of degrees of freedom should be minimal without losing the necessary accuracy, especially for local stiffness modifications. A technique for this is proposed that uses Component Mode Synthesis (CMS) methods to redu...

  18. April 2002 Working Group Meeting on Heavy Vehicle Aerodynamic Drag: Presentations and Summary of Comments and Conclusions

    Energy Technology Data Exchange (ETDEWEB)

    Salari, K; Dunn, T; Ortega, J; Yen-Nakafuji, D; Browand, F; Arcas, D; Jammache, M; Leoard, A; Chatelain, P; Rubel, M; Rutledge, W; McWherter-Payne, M; Roy, Ca; Ross, J; Satran, D; Heineck, J T; Storms, B; Pointer, D; Sofu, T; Weber, D; Chu, E; Hancock, P; Bundy, B; Englar, B

    2002-08-22

    A Working Group Meeting on Heavy Vehicle Aerodynamic Drag was held at Lawrence Livermore National Laboratory on April 3 and 4, 2002. The purpose of the meeting was to present and discuss technical details on the experimental and computational work in progress and future project plans. Representatives from the Department of Energy (DOE) Office of Transportation Technology Office of Heavy Vehicle Technology (OHVT), Lawrence Livermore National Laboratory (LLNL), Sandia National Laboratories (SNL), NASA Ames Research Center, University of Southern California (USC), and California Institute of Technology (Caltech), Georgia Tech Research Institute (GTRI), and Argonne National Laboratory (ANL), Volvo Trucks, and Freightliner Trucks presented and participated in discussions. This report contains the technical presentations (viewgraphs) delivered at the Meeting, briefly summarizes the comments and conclusions, and outlines the future action items.

  19. May 2003 Working Group Meeting on Heavy Vehicle Aerodynamic Drag: Presentations and Summary of Comments and Conclusions

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, R; Salari, K; Ortega, J; Browand, F; Hammache, M; Hsu, T Y; Arcas, D; Leoard, A; Chatelain, P; Rubel, M; Roy, C; DeChant, L; Hassan, B; Ross, J; Satran, D; Walker, S; Heineck, J T; Englar, R; Pointer, D; Sofu, T

    2003-05-01

    A Working Group Meeting on Heavy Vehicle Aerodynamic Drag was held at Lawrence Livermore National Laboratory on May 29-30, 2003. The purpose of the meeting was to present and discuss suggested guidance and direction for the design of drag reduction devices determined from experimental and computational studies. Representatives from the Department of Energy (DOE)/Office of Energy Efficiency and Renewable Energy/Office of FreedomCAR & Vehicle Technologies, Lawrence Livermore National Laboratory (LLNL), Sandia National Laboratories (SNL), NASA Ames Research Center (NASA), University of Southern California (USC), California Institute of Technology (Caltech), Georgia Tech Research Institute (GTRI), Argonne National Laboratory (ANL), Clarkson University, and PACCAR participated in the meeting. This report contains the technical presentations (viewgraphs) delivered at the Meeting, briefly summarizes the comments and conclusions, provides some highlighted items, and outlines the future action items.

  20. Aerodynamic Interactions Between Contralateral Wings and Between Wings and Body of a Model Insect at Hovering and Small Speed Motions

    Institute of Scientific and Technical Information of China (English)

    LIANG Bin; SUN Mao

    2011-01-01

    In this paper,we study the aerodynamic interactions between the contralateral wings and between the body and wings of a model insect,when the insect is hovering and has various translational and rotational motions,using the method numerically solving the Navier-Stokes equations over moving overset grids.The aerodynamic interactional effects are identified by comparing the results of a complete model insect,the corresponding wing pair,single wing and body without the wings.Horizontal,vertical and lateral translations and roll,pitch and yaw rotations at small speeds are considered.The results indicate that for the motions considered,both the interaction between the contralateral wings and the interaction between the body and wings are weak.The changes in the forces and moments of a wing due to the contralateral wing interaction,of the wings due to the presence of the body,and of the body due to the presence of the wings are generally less than 4.5%.Results show that aerodynamic forces of wings and body can be measured or computed separately in the analysis of flight stability and control of hovering insects.

  1. Component sizing optimization of plug-in hybrid electric vehicles

    International Nuclear Information System (INIS)

    Plug-in hybrid electric vehicles (PHEVs) are considered as one of the most promising means to improve the near-term sustainability of the transportation and stationary energy sectors. This paper describes a methodology for the optimization of PHEVs component sizing using parallel chaos optimization algorithm (PCOA). In this approach, the objective function is defined so as to minimize the drivetrain cost. In addition, the driving performance requirements are considered as constraints. Finally, the optimization process is performed over three different all electric range (AER) and two types of batteries. The results from computer simulation show the effectiveness of the approach and the reduction in drivetrian cost while ensuring the vehicle performance.

  2. Aerodynamic Optimal Shape Design Based on Body-Fitted Grid Generation

    Directory of Open Access Journals (Sweden)

    Farzad Mohebbi

    2014-01-01

    Full Text Available This paper is concerned with an optimal shape design problem in aerodynamics. The inverse problem in question consists in finding the optimal shape an airfoil placed in a potential flow at a given angle of attack should have such that the pressure distribution on its surface matches a desired one. The numerical method to achieve this aim is based on a body-fitted grid generation technique (elliptic, O-type to generate a mesh over the airfoil surface and solve for the flow equation. The O-type scheme is used due to its ability to generate a high quality (fine and orthogonal grid around the airfoil surface. This paper describes a novel and very efficient sensitivity analysis scheme to compute the sensitivity of the pressure distribution to variation of grid node positions and both the conjugate gradient method (CGM and a version of the quasi-Newton method (i.e., BFGS are used as optimization algorithms to minimize the difference between the computed pressure distribution on the airfoil surface and desired one. The elliptic grid generation technique allows us to map the physical domain (body onto a fixed computational domain and to discretize the flow equation using the finite difference method (FDM.

  3. The influence of aerodynamic coefficients on the elements of classic projectile paths

    Directory of Open Access Journals (Sweden)

    Damir D. Jerković

    2011-04-01

    Full Text Available The article deals with the results of the research on the influence of aerodynamic coefficient values on the trajectory elements and the stability parameters of classic axisymmetric projectiles. It presents the characteristic functions of aerodynamic coefficients with regard to aerodynamic parameters and the projectile body shape. The trajectory elements of the model of classic axisymmetric projectiles and the analyses of their changes were presented with respect to the aerodynamic coefficient values. Introduction Classic axisymmetric projectiles fly through atmosphere using muzzle velocity as initial energy resource, so the aerodynamic force and moment have the most significant influence on the motion of projectiles. The aerodynamic force and moment components represented as aerodynamic coefficients depend on motion velocity i. e. flow velocity, the flow features produced by projectile shape and position in the flow, and angular velocity (rate of the body. The functional dependence of aerodynamic coefficients on certain influential parameters, such as angle of attack and angular velocity components is expressed by the derivative of aerodynamic coefficients. The determination of aerodynamic coefficients and derivatives enables complete definition of the aerodynamic force and moment acting on the classic projectile. The projectile motion problem is considered in relation to defining the projectile stability parameters and the conditions under which the stability occurs. The comparative analyses of aerodynamic coefficient values obtained by numerical methods, semi empirical calculations and experimental research give preliminary evaluation of the quality of the determined values. The flight simulation of the motion of a classic axisymetric projectile, which has the shape defined by the aerodynamic coefficient values, enables the comparative analyses of the trajectory elements and stability characteristics. The model of the classic projectile

  4. Design of a compact six-component force and moment sensor for aerodynamic testing

    Directory of Open Access Journals (Sweden)

    Georgeta IONAŞCU

    2011-03-01

    Full Text Available The measurement of steady and fluctuating forces acting on a body in a flow is one of themain tasks in wind-tunnel experiments. Usually, a multi-component strain gauge force and momentsensor (also known as balance is used to generate signals which are processed by means of anadequate instrumentation.To design a wind-tunnel balance, the specifications of the load ranges and the available space (for theplacement of the balance inside or outside the model are required. The main challenge is to conceivethe elastic element of the sensor as a monolithic part with a relative simple geometry and to identifythe adequate placement of strain gauges to maximize the measuring sensitivities and to diminish theinter-influence of the components.This paper describes the design of a six-component force/moment sensor which is compact, has highmeasuring sensitivities, and can be used either as internal or as external balance in the aerodynamictesting.

  5. Numerical aerodynamic analysis of bluff bodies at a high Reynolds number with three-dimensional CFD modeling

    Science.gov (United States)

    Bai, YuGuang; Yang, Kai; Sun, DongKe; Zhang, YuGuang; Kennedy, David; Williams, Fred; Gao, XiaoWei

    2013-02-01

    This paper focuses on numerical simulations of bluff body aerodynamics with three-dimensional CFD (computational fluid dynamics) modeling, where a computational scheme for fluid-structure interactions is implemented. The choice of an appropriate turbulence model for the computational modeling of bluff body aerodynamics using both two-dimensional and three-dimensional CFD numerical simulations is also considered. An efficient mesh control method which employs the mesh deformation technique is proposed to achieve better simulation results. Several long-span deck sections are chosen as examples which were stationary and pitching at a high Reynolds number. With the proposed CFD method and turbulence models, the force coefficients and flutter derivatives thus obtained are compared with the experimental measurement results and computed values completely from commercial software. Finally, a discussion on the effects of oscillation amplitude on the flutter instability of a bluff body is carried out with extended numerical simulations. These numerical analysis results demonstrate that the proposed three-dimensional CFD method, with proper turbulence modeling, has good accuracy and significant benefits for aerodynamic analysis and computational FSI studies of bluff bodies.

  6. Unsteady Aerodynamic Investigation of the Propeller-Wing Interaction for a Rocket Launched Unmanned Air Vehicle

    OpenAIRE

    Zhang, G Q; Yu, S. C. M.; A. Chien; Xu, Y

    2013-01-01

    The aerodynamic characteristics of propeller-wing interaction for the rocket launched UAV have been investigated numerically by means of sliding mesh technology. The corresponding forces and moments have been collected for axial wing placements ranging from 0.056 to 0.5D and varied rotating speeds. The slipstream generated by the rotating propeller has little effects on the lift characteristics of the whole UAV. The drag can be seen to remain unchanged as the wing's location moves progressive...

  7. Structural design optimization of vehicle components using Cuckoo Search Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Yildiz, Ali Riza [Bursa Technical Univ., Bursa (Turkey). Dept. of Mechanical Engineering; Durgun, Ismail

    2012-07-01

    In order to meet today's vehicle design requirements and to improve the cost and fuel efficiency, there is an increasing interest to design light-weight and cost-effective vehicle components. In this research, a new optimization algorithm, called the Cuckoo Search Algorithm (CS) algorithm, is introduced for solving structural design optimization problems. This research is the first application of the CS to the shape design optimization problems in the literature. The CS algorithm is applied to the structural design optimization of a vehicle component to illustrate how the present approach can be applied for solving structural design problems. Results show the ability of the CS to find better optimal structural design. [German] Um heutige Anforderungen an das Fahrzeugdesign zu beruecksichtigen und um die Kosten- und Kraftstoffeffektivitaet zu erhoehen, nimmt das Interesse am Design leichter und kosteneffektiver Fahrzeugkomponenten weiterhin zu. In der diesem Beitrag zugrunde liegenden Studie wurde ein neuer Optimierungsalgorithmus angewendet, der so genannte Cuckoo Suchalgorithmus (CS). Es handelt sich um die erste CS-Applikation fuer das Formdesign in der Literatur. Der CS-Algorithmus wird hierbei zur Strukturdesignoptimierung einer Fahrzeugkomponente angewendet, um zu zeigen, wie er bei der Loesung von Strukturdesignaufgaben angewendet werden kann. Die Ergebnisse zeigen, wie damit ein verbessertes Design erreicht werden kann.

  8. Effective aerodynamic roughness estimated from airborne laser altimeter measurements of surface features

    OpenAIRE

    de Vries, AC; Kustas, WP; Ritchie, JC; Klaassen, W.; M. Menenti; Rango, A; Prueger, JH

    2003-01-01

    Aerodynamic roughness length (z(0)) and displacement height (d(0)) are important surface parameters for estimating surface fluxes in numerical models. These parameters are generally determined from wind flow characteristics using logarithmic wind profiles measured at a meteorological tower or by balloon release. It would be an advantage to use measurements of land surface characteristics instead of wind flow characteristics to estimate the z(0), and d(0) for large areas. Important land surfac...

  9. March 2001 Working Group Meeting on Heavy Vehicle Aerodynamic Drag: Presentations and Summary of Comments and Conclusions

    Energy Technology Data Exchange (ETDEWEB)

    Greenman, R; Dunn, T; Owens, J; Laskowski, G; Flowers, D; Browand, F; Knight, A; Hammache, M; Leoard, A; Rubel, M; Salari, K; Rutledge, W; Ross, J; Satran, D; Heineck, J T; Walker, S; Driver, D; Storms, B

    2001-05-14

    A Working Group Meeting on Heavy Vehicle Aerodynamic Drag was held at Lawrence Livermore National Laboratory on March 28 and 29, 2001. The purpose of the meeting was to present and discuss technical details on the experimental and computational work in progress and future project plans. Due to the large participation from industry and other research organizations, a large portion of the meeting (all of the first day and part of the second day) was devoted to the presentation and discussion of industry's perspective and work being done by other organizations on the demonstration of commercial software and the demonstration of a drag reduction device. This report contains the technical presentations (viewgraphs) delivered at the Meeting, briefly summarizes the comments and conclusions, and outlines the future action items.

  10. September 2002 Working Group Meeting on Heavy Vehicle Aerodynamic Drag: Presentations and Summary of Comments and Conclusions

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, R

    2002-09-01

    A Working Group Meeting on Heavy Vehicle Aerodynamic Drag was held at NASA Ames Research Center on September 23, 2002. The purpose of the meeting was to present and discuss technical details on the experimental and computational work in progress and future project plans. Representatives from the Department of Energy (DOE)/Office of Energy Efficiency and Renewable Energy/Office of FreedomCAR & Vehicle Technologies, Lawrence Livermore National Laboratory (LLNL), Sandia National Laboratories (SNL), NASA Ames Research Center (NASA), University of Southern California (USC), California Institute of Technology (Caltech), Georgia Tech Research Institute (GTRI), Argonne National Laboratory (ANL), Freightliner, and Portland State University participated in the meeting. This report contains the technical presentations (viewgraphs) delivered at the Meeting, briefly summarizes the comments and conclusions, and outlines the future action items. The meeting began with an introduction by the Project Lead Rose McCallen of LLNL, where she emphasized that the world energy consumption is predicted to relatively soon exceed the available resources (i.e., fossil, hydro, non-breeder fission). This short fall is predicted to begin around the year 2050. Minimizing vehicle aerodynamic drag will significantly reduce our Nation's dependence on foreign oil resources and help with our world-wide fuel shortage. Rose also mentioned that educating the populace and researchers as to our world energy issues is important and that our upcoming United Engineering Foundation (UEF) Conference on ''The Aerodynamics of Heavy Vehicles: Trucks, Busses, and Trains'' was one way our DOE Consortium was doing this. Mentioned were the efforts of Fred Browand from USC in organizing and attracting internationally recognized speakers to the Conference. Rose followed with an overview of the DOE project goals, deliverables, and FY03 activities. The viewgraphs are attached at the end of this

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

    Science.gov (United States)

    Stanley, Thomas Troy; Alexander, Reginald

    1999-01-01

    Presented is a computer-based tool that connects several disciplines that are needed in the complex and integrated design of high performance reusable single stage to orbit (SSTO) vehicles. Every system is linked to every other system, as is the case of SSTO vehicles with air breathing propulsion, which is currently being studied by NASA. The deficiencies in the scramjet powered concept led to a revival of interest in Rocket-Based Combined-Cycle (RBCC) propulsion systems. An RBCC propulsion system integrates airbreathing and rocket propulsion into a single engine assembly enclosed within a cowl or duct. A typical RBCC propulsion system operates as a ducted rocket up to approximately Mach 3. At this point the transitions to a ramjet mode for supersonic-to-hypersonic acceleration. Around Mach 8 the engine transitions to a scram4jet mode. During the ramjet and scramjet modes, the integral rockets operate as fuel injectors. Around Mach 10-12 (the actual value depends on vehicle and mission requirements), the inlet is physically closed and the engine transitions to an integral rocket mode for orbit insertion. A common feature of RBCC propelled vehicles is the high degree of integration between the propulsion system and airframe. At high speeds the vehicle forebody is fundamentally part of the engine inlet, providing a compression surface for air flowing into the engine. The compressed air is mixed with fuel and burned. The combusted mixture must be expanded to an area larger than the incoming stream to provide thrust. Since a conventional nozzle would be too large, the entire lower after body of the vehicle is used as an expansion surface. Because of the high external temperatures seen during atmospheric flight, the design of an airbreathing SSTO vehicle requires delicate tradeoffs between engine design, vehicle shape, and thermal protection system (TPS) sizing in order to produce an optimum system in terms of weight (and cost) and maximum performance.

  12. Analysis of modal frequency optimization of railway vehicle car body

    Directory of Open Access Journals (Sweden)

    Wenjing Sun

    2016-04-01

    Full Text Available High structural modal frequencies of car body are beneficial as they ensure better vibration control and enhance ride quality of railway vehicles. Modal sensitivity optimization and elastic suspension parameters used in the design of equipment beneath the chassis of the car body are proposed in order to improve the modal frequencies of car bodies under service conditions. Modal sensitivity optimization is based on sensitivity analysis theory which considers the thickness of the body frame at various positions as variables in order to achieve optimization. Equipment suspension design analyzes the influence of suspension parameters on the modal frequencies of the car body through the use of an equipment-car body coupled model. Results indicate that both methods can effectively improve the modal parameters of the car body. Modal sensitivity optimization increases vertical bending frequency from 9.70 to 10.60 Hz, while optimization of elastic suspension parameters increases the vertical bending frequency to 10.51 Hz. The suspension design can be used without alteration to the structure of the car body while ensuring better ride quality.

  13. July 1999 working group meeting on heavy vehicle aerodynamic drag: presentations and summary of comments and conclusions

    Energy Technology Data Exchange (ETDEWEB)

    Brady, M; Browand, F; Flowers, D; Hammache, M; Landreth, G; Leonard, A; McCallen, R; Ross, J; Rutledge, W; Salari, K

    1999-08-16

    A Working Group Meeting on Heavy Vehicle Aerodynamic Drag was held at University of Southern California, Los Angeles, California on July 30, 1999. The purpose of the meeting was to present technical details on the experimental and computational plans and approaches and provide an update on progress in obtaining experimental results, model developments, and simulations. The focus of the meeting was a review of University of Southern California's (USC) experimental plans and results and the computational results from Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL) for the integrated tractor-trailer benchmark geometry called the Sandia Model. Much of the meeting discussion involved the NASA Ames 7 ft x 10 ft wind tunnel tests and the need for documentation of the results. The present and projected budget and funding situation was also discussed. Presentations were given by representatives from the Department of Energy (DOE) Office of Transportation Technology Office of Heavy Vehicle Technology (OHVT), LLNL, SNL, USC, and California Institute of Technology (Caltech). This report contains the technical presentations (viewgraphs) delivered at the Meeting, briefly summarizes the comments and conclusions, and outlines the future action items.

  14. Cross body thruster control and modeling of a body of revolution Autonomous Underwater Vehicle

    OpenAIRE

    Doherty, Sean Michael.

    2011-01-01

    Approved for public release; distribution is unlimited. Cross body thrusters permit a body of revolution Autonomous Underwater Vehicle to retain the energy efficiency of forward travel while increasing the ability to maneuver in confined areas such as harbors and piers. This maneuverability also permits more deliberate underwater surveys using a fixed, mounted forward and downward looking sonar. This work develops the necessary hydrodynamic coefficients, using methods applied to earlier ve...

  15. HUNTING STABILITY OF HIGH-SPEED RAILWAY VEHICLE CONSIDERING THE ACTIONS OF STEADY AERODYNAMIC LOADS%定常气动载荷作用下高速铁路车辆的蛇行运动稳定性

    Institute of Scientific and Technical Information of China (English)

    曾晓辉; 赖姜

    2013-01-01

    With the enhancement of the speed of trains, the aerodynamic loads will deteriorate the hunting stability of motion of railway vehicles. There is seldom study on this problem. For this reason, the hunting stability of a high-speed railway vehicle is studied, considering the steady aerodynamic loads resulting from the actions of crosswind and airflow in the opposite advancing direction of train. The effects of variations of axle loads, creep coefficients, gravitational stiffness and angular stiffness due to actions of aerodynamic loads are taken into account. A mathematical model for hunting stability analysis of vehicle with 17 degrees of freedom is presented, in which the effects of aerodynamic loads are incorporated. A program based on the presented model is written and verified. And then, in different wind velocities, with cases for each component of aerodynamic force and moment acting individually and collectively being considered, the eigenvalues of hunting stability of vehicle are calculated. Furthermore, the critical velocities are obtained. It is shown that, aerodynamic loads can decrease the critical velocity of vehicle; the critical velocity decreases monotonously as the velocity of beam wind increases; the influences of pitch moment and lift force on critical velocity are larger than that of other components of aerodynamic loads.%随着高速列车运行速度的提高,气动载荷会对车辆蛇行运动稳定性带来不利影响,现有文献对此研究很少.为此,考虑沿列车反向运动高速气流以及侧风的作用,研究了定常气动载荷下高速铁路车辆横向运动的线性稳定性.分析中计入了气动载荷改变轴重、使各轮法向支反力各不相同;以及使重力刚度、重力角刚度、轮对蠕滑系数等发生变化的效应.给出了计及气动影响的17个自由度铁路车辆蛇行运动分析模型,编制了相应的计算程序并进行了算例验证.进而,计算了在不同风速条件下,各个

  16. Aerodynamics of flapping-wing Micro-Air-Vehicle: An integrated experimental and numerical study

    NARCIS (Netherlands)

    Deng, S.

    2016-01-01

    The interest in Micro Air Vehicles (MAVs) has stimulated continuous research activities, in view of their potential in civilian and military applications. An autonomous MAV with dedicated onboard sensors would be capable of executing mission in closed environments, such as surveillance, in door insp

  17. Stop and Restart Effects on Modern Vehicle Starting System Components

    Energy Technology Data Exchange (ETDEWEB)

    Windover, Paul R. [Argonne National Lab. (ANL), Argonne, IL (United States); Owens, Russell J. [Argonne National Lab. (ANL), Argonne, IL (United States); Levinson, Terry M. [Argonne National Lab. (ANL), Argonne, IL (United States); Laughlin, Michael [Argonne National Lab. (ANL), Argonne, IL (United States); Gaines, Linda [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-01-01

    Many drivers of personal and commercial vehicles believe that turning the vehicle off and on frequently instead of idling will cause premature wear of the starter system (starter motor and starter battery). As a result, they are concerned that the replacement cost of the starter motor and/or battery due to increased manual engine cycling would be more than the cumulative cost of the fuel saved by not idling unnecessarily. A number of variables play a role in addressing this complex concern, including the number of starting cycles per day, the time between starting cycles, the intended design life of the starting system, the amount of fuel used to restart an engine, and the cumulative cost of the saved fuel. Qualitative and quantitative information from a variety of sources was used to develop a life-cycle economic model to evaluate the cost and quantify the realistic factors that are related to the permissible frequency of starter motor cycles for the average vehicle to economically minimize engine idle time. Annual cost savings can be calculated depending on shutdown duration and the number of shutdown cycles per day. Analysis shows that cost savings are realized by eliminating idling exceeding one minute by shutting down the engine and restarting it. For a typical motorist, the damage to starting system components resulting from additional daily start cycles will be negligible. Overall, it was found that starter life is mostly dependent on the total number of start cycles, while battery life is more dependent on ensuring a full charge between start events.

  18. One Low-cost Quartz Lamp Radiation Aerodynamic Heating Simulation Experiment System with Control Law Flexible Adjustment Feature

    Directory of Open Access Journals (Sweden)

    Wang Decheng

    2015-01-01

    Full Text Available The quartz lamp radiation aerodynamic heating simulation experiment system plays an important role on the structure strength heat experiment. In order to reduce its price and enhance flexibility on control law design of experiment system, a design method for low-cost quartz lamp radiation aerodynamic heating simulation experiment system with control law flexible adjustment feature is proposed. The hardware part is constructed by taking Digital Signal Processor (DSP as an implementing agency controller. The feedback temperature after processed is computed by DSP. But the experiment process control value is computed by computer. The feedback temperature and experiment process control value data are transferred by serial communication model between DSP and computer. The experiment process relation data is saved by computer with EXCEL file, including the given target spectrum, the feedback temperature and the control value. The results of experiments on system identification, PID spectrum tracking, different zone control and the open loop control show the effectiveness of the proposed method.

  19. Clustering and Feature Selection using Sparse Principal Component Analysis

    OpenAIRE

    Luss, Ronny; d'Aspremont, Alexandre

    2007-01-01

    In this paper, we study the application of sparse principal component analysis (PCA) to clustering and feature selection problems. Sparse PCA seeks sparse factors, or linear combinations of the data variables, explaining a maximum amount of variance in the data while having only a limited number of nonzero coefficients. PCA is often used as a simple clustering technique and sparse factors allow us here to interpret the clusters in terms of a reduced set of variables. We begin with a brief int...

  20. Reduction of aerodynamic drag and fuel consumption for tractor-trailer vehicles

    Science.gov (United States)

    Muirhead, V. U.; Saltzman, E. J.

    1979-01-01

    Wind-tunnel tests were performed on a scale model of a cab-over-engine tractor-trailer vehicle and several modifications of the model. Results from two of the model configurations were compared with full-scale drag data obtained from similar configurations during coast-down tests. Reductions in fuel consumption derived from these tests are presented in terms of fuel quantity and dollar savings per vehicle year, based on an annual driving distance of 160,900 km (100,000 mi.). The projected savings varied from 13,001 (3435) to 25,848 (6829) liters (gallons) per year which translated to economic savings from $3435 to about $6829 per vehicle year for an operating speed of 88.5 km/h (55 mph) and wind speeds near the national average of 15.3 km/h (9.5 mph). The estimated cumulative fuel savings for the entire U.S. fleet of cab-over-engine tractor, van-type trailer combinations ranged from 4.18 million kl (26.3 million bbl) per year for a low-drag configuration to approximately twice that amount for a more advanced configuration.

  1. Extracting Epileptic Feature Spikes Using Independent Component Analysis

    Institute of Scientific and Technical Information of China (English)

    YAN Hong-mei; XIA Yang; LIU Yan-su; LAI Yong-xiu; YAO De-zhong; ZHOU Dong

    2005-01-01

    In recent years, blind source separation (BSS) by independent component analysis (ICA) has been drawing much attention because of its potential applications in signal processing such as in speech recognition systems, telecommunication and medical signal processing. In this paper, two algorithms of independent component analysis (fixed-point ICA and natural gradient-flexible ICA) are adopted to extract human epileptic feature spikes from interferential signals. Experiment results show that epileptic spikes can be extracted from noise successfully. The kurtosis of the epileptic component signal separated is much better than that of other noisy signals. It shows that ICA is an effective tool to extract epileptic spikes from patients' electroencephalogram EEG and shows promising application to assist physicians to diagnose epilepsy and estimate the epileptogenic region in clinic.

  2. Overview of Low-Speed Aerodynamic Tests on a 5.75% Scale Blended-Wing-Body Twin Jet Configuration

    Science.gov (United States)

    Vicroy, Dan D.; Dickey, Eric; Princen, Norman; Beyar, Michael D.

    2016-01-01

    The NASA Environmentally Responsible Aviation (ERA) Project sponsored a series of computational and experimental investigations of the propulsion and airframe integration issues associated with Hybrid-Wing-Body (HWB) or Blended-Wing-Body (BWB) configurations. NASA collaborated with Boeing Research and Technology (BR&T) to conduct this research on a new twin-engine Boeing BWB transport configuration. The experimental investigations involved a series of wind tunnel tests with a 5.75-percent scale model conducted in two low-speed wind tunnels. This testing focused on the basic aerodynamics of the configuration and selection of the leading edge Krueger slat position for takeoff and landing. This paper reviews the results and analysis of these low-speed wind tunnel tests.

  3. AERODYNAMIC SOUND OF A BODY IN ARBITRARY, DEFORMABLE MOTION, WITH APPLICATION TO PHONATION

    OpenAIRE

    Howe, M. S.; McGowan, R. S.

    2013-01-01

    The method of tailored Green’s functions advocated by Doak (Proceedings of the Royal Society A254 (1960) 129 – 145.) for the solution of aeroacoustic problems is used to analyse the contribution of the mucosal wave to self-sustained modulation of air flow through the glottis during the production of voiced speech. The amplitude and phase of the aerodynamic surface force that maintains vocal fold vibration are governed by flow separation from the region of minimum cross-sectional area of the g...

  4. Feature and Pose Constrained Visual Aided Inertial Navigation for Computationally Constrained Aerial Vehicles

    Science.gov (United States)

    Williams, Brian; Hudson, Nicolas; Tweddle, Brent; Brockers, Roland; Matthies, Larry

    2011-01-01

    A Feature and Pose Constrained Extended Kalman Filter (FPC-EKF) is developed for highly dynamic computationally constrained micro aerial vehicles. Vehicle localization is achieved using only a low performance inertial measurement unit and a single camera. The FPC-EKF framework augments the vehicle's state with both previous vehicle poses and critical environmental features, including vertical edges. This filter framework efficiently incorporates measurements from hundreds of opportunistic visual features to constrain the motion estimate, while allowing navigating and sustained tracking with respect to a few persistent features. In addition, vertical features in the environment are opportunistically used to provide global attitude references. Accurate pose estimation is demonstrated on a sequence including fast traversing, where visual features enter and exit the field-of-view quickly, as well as hover and ingress maneuvers where drift free navigation is achieved with respect to the environment.

  5. Path instabilities of heavy bodies in free fall in a viscous fluid: wake dynamics vs. aerodynamic effects

    Science.gov (United States)

    Fabre, David; Selvam, Kamal; Tchoufag, Joël; Assemat, Pauline; Magnaudet, Jacques

    2013-11-01

    Solid bodies in free fall in a viscous fluid generally fall along a non-straight path, and a variety of periodic (fluttering, tumbling) and non-periodic regimes can be observed. We analyze the structure of the couplings between the fluid and the body, restricting to a linear stability framework. Introducing a simple toy model consisting of a infinitely long plate sliding along a vertical wall, we show that in the limit of large solid-to-fluid masses a decoupling takes place, allowing us to distinguish two kinds of modes: ``wake'' modes in which the body motion has virtually no influence, and ``body'' modes for which the intrinsic wake dynamics can be neglected. Turning to more realistic objects, we show that the ``body'' modes can be described through a rationally derived aerodynamic model (based on quasi-static assumptions), yielding either a static instability, or a dynamic, low-frequency, instability. Considering 2D rectangular rods and 3D disks, we explore the competition between the three kinds of instabilities. For objects elongated in the spanwise direction, it is found that wake instability dominates in case of 2D rectangles and low-frequency instability dominates in case of disks. For objects elongated in the streamwise direction, static instability always dominate.

  6. Numerical Investigation on Aerodynamic Characteristics of Box-wing Unmanned Aerial Vehicle%盒式翼无人机气动特性数值计算分析

    Institute of Scientific and Technical Information of China (English)

    刘毅; 靳宏斌

    2014-01-01

    传统方法求解盒式翼无人机的气动特性有一定的局限性,某无人机采用负交错的盒式翼布局,翼尖高差约为5%展长,翼面系统各部件之间的干扰影响复杂。为了获得其失速特性、升降舵效率等粘性作用强烈的边界气动特性,通过雷诺平均Navior-Stokes方法分析其极曲线、失速特性和俯仰力矩特性。结果表明:诱导阻力相对同等单翼降低约9%,与理论结果接近;后翼采用-4°的有效负安装角,导致配平后最大升力系数降低较多;大迎角失速时出现抬头力矩,与前翼后掠导致的翼尖失速以及后翼位于前翼尾流中效率降低有关。%Solving aerodynamic characteristics of box-wing unmanned aerial vehicle(UAV)by traditional methods is of certain limitations .For a box-wing UAV using negative stagger and wing tip gap of 5% wing span ,the strong interference exist between components of the wing systems .In order to study boundary aerodynamic characteristics effected strongly by viscous interaction of box-wing UAV ,which concludes stall characteristics and efficiency of elevator etc .,Reynolds Averaged Navior-Stokes scheme is adopted to analyze its drag polar , stall and pitching moment characteristics .The research reveals that the induced drag is reduced by 9% com-pared with equal mono-wing ,which is close to the theoretical result ;The trimmed maximum lift coefficient drops significantly due to the requirements of static stability and trim ,which are realized by -4° negative instal-ling angle of aft wing ;Nose up pitching moment is observed at large angle of attack after stall ,which attributes to the forward wing tip stall due to its sweptback ,as well as the decreased efficiency of the aft wing in the wake of the forward wing .

  7. Modeling and Analysis of an Air-Breathing Flexible Hypersonic Vehicle

    OpenAIRE

    Xi-bin Zhang; Qun Zong

    2014-01-01

    By using light-weighted material in hypersonic vehicle, the vehicle body can be easily deformed. The mutual couplings in aerodynamics, flexible structure, and propulsion system will bring great challenges for vehicle modeling. In this work, engineering estimated method is used to calculate the aerodynamic forces, moments, and flexible modes to get the physics-based model of an air-breathing flexible hypersonic vehicle. The model, which contains flexible effects and viscous effects, can captur...

  8. AERODYNAMIC SOUND OF A BODY IN ARBITRARY, DEFORMABLE MOTION, WITH APPLICATION TO PHONATION.

    Science.gov (United States)

    Howe, M S; McGowan, R S

    2013-08-19

    The method of tailored Green's functions advocated by Doak (Proceedings of the Royal Society A254 (1960) 129 - 145.) for the solution of aeroacoustic problems is used to analyse the contribution of the mucosal wave to self-sustained modulation of air flow through the glottis during the production of voiced speech. The amplitude and phase of the aerodynamic surface force that maintains vocal fold vibration are governed by flow separation from the region of minimum cross-sectional area of the glottis, which moves back and forth along its effective length accompanying the mucosal wave peak. The correct phasing is achieved by asymmetric motion of this peak during the opening and closing phases of the glottis. Limit cycle calculations using experimental data of Berry et al. (Journal of the Acoustical Society of America 110 (2001) 2539 - 2547.) obtained using an excised canine hemilarynx indicate that the mechanism is robust enough to sustain oscillations over a wide range of voicing conditions. PMID:24031098

  9. Numerical modeling of aerodynamics of airfoils of micro air vehicles in gusty environment

    Science.gov (United States)

    Gopalan, Harish

    The superior flight characteristics exhibited by birds and insects can be taken as a prototype of the most perfect form of flying machine ever created. The design of Micro Air Vehicles (MAV) which tries mimic the flight of birds and insects has generated a great deal of interest as the MAVs can be utilized for a number of commercial and military operations which is usually not easily accessible by manned motion. The size and speed of operation of a MAV results in low Reynolds number flight, way below the flying conditions of a conventional aircraft. The insensitivity to wind shear and gust is one of the required factors to be considered in the design of airfoil for MAVs. The stability of flight under wind shear is successfully accomplished in the flight of birds and insects, through the flapping motion of their wings. Numerous studies which attempt to model the flapping motion of the birds and insects have neglected the effect of wind gust on the stability of the motion. Also sudden change in flight conditions makes it important to have the ability to have an instantaneous change of the lift force without disturbing the stability of the MAV. In the current study, two dimensional rigid airfoil, undergoing flapping motion is studied numerically using a compressible Navier-Stokes solver discretized using high-order finite difference schemes. The high-order schemes in space and in time are needed to keep the numerical solution economic in terms of computer resources and to prevent vortices from smearing. The numerical grid required for the computations are generated using an inverse panel method for the streamfunction and potential function. This grid generating algorithm allows the creation of single-block orthogonal H-grids with ease of clustering anywhere in the domain and the easy resolution of boundary layers. The developed numerical algorithm has been validated successfully against benchmark problems in computational aeroacoustics (CAA), and unsteady viscous

  10. Clustering and Feature Selection using Sparse Principal Component Analysis

    CERN Document Server

    Luss, Ronny

    2007-01-01

    In this paper, we use sparse principal component analysis (PCA) to solve clustering and feature selection problems. Sparse PCA seeks sparse factors, or linear combinations of the data variables, explaining a maximum amount of variance in the data while having only a limited number of nonzero coefficients. PCA is often used as a simple clustering technique and sparse factors allow us here to interpret the clusters in terms of a reduced set of variables. We begin with a brief introduction and motivation on sparse PCA and detail our implementation of the algorithm in d'Aspremont et al. (2005). We finish by describing the application of sparse PCA to clustering and by a brief description of DSPCA, the numerical package used in these experiments.

  11. 风区车站停留车辆纵向气动力研究%Longitudinal aerodynamic force of vehicles in wind area

    Institute of Scientific and Technical Information of China (English)

    李志伟; 刘堂红; 张洁; 任鑫

    2013-01-01

    为了确定风区站停车辆的手制动车辆数,避免车辆溜逸事故的发生,利用风洞和三维数值计算方法对风速、风向角、防风设施、编组不同的车辆纵向气动力进行分析.研究结果表明:车辆所受纵向气动力与风速的平方成正比;当风向角为30°左右时,车辆所受到的纵向气动力最大;不同车辆编组时,头、中、尾车的纵向气动力均比较接近,最大相对误差为4.7%,可减少中间车编组数,提高计算效率;有挡风墙时车辆所受的纵向气动力小于无挡风墙车辆所受的纵向气动力,砼板式挡风墙的防护效果比土堤式挡风墙的优;风洞试验结果与数值计算结果基本相同;风区车站停留车辆纵向气动力研究为车辆防溜分析、车辆手制动数的确定提供了车辆纵向气动力计算载荷.%In order to determine the number of vehicles using hand brake in the stations of wind area, and to prevent the vehicles runaway, wind tunnel tests and three-dimensional numerical calculation were used to analyze the influence of wind speed, wind direction, wind-break facility and vehicle composition on longitudinal aerodynamic force. The results show that the longitudinal aerodynamic force is proportional to the square of the wind speed, and it is the largest when the wind angle is about 30°. Vehicle composition is different, the longitudinal aerodynamic forces of head car, middle car and end car are approximate, and the maximum relative difference is 4.7%, thus, the number of intermediate cars can be reduced to improve the calculation efficiency. Longitudinal aerodynamic force of vehicle behind wind-break wall is less than that of no wind-break wall, and the protective effect of the concrete wind-break wall is better than the embankment wind-break wall. The results of wind tunnel test and numerical calculation are almost the same. Longitudinal aerodynamic force analysis can provide aerodynamic loads for vehicle anti

  12. Hybrid Computational Model for High-Altitude Aeroassist Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A hybrid continuum/noncontinuum computational model will be developed for analyzing the aerodynamics and heating on aeroassist vehicles. Unique features of this...

  13. The Aerodynamic Forces on Slender Plane- and Cruciform-Wing and Body Combinations

    Science.gov (United States)

    Spreiter, John R

    1950-01-01

    The load distribution, forces, and moments are calculated theoretically for inclined slender wing-body combinations consisting of a slender body of revolution and either a plane or cruciform arrangement of low-aspect-ratio pointed wings. The results are applicable at subsonic and transonic speeds, and at supersonic speeds, provided the entire wing-body combination lies near the center of the Mach cone.

  14. ZEUS-DO: A Design Oriented CFD-Based Unsteady Aerodynamic Capability for Flight Vehicle Multidisciplinary Configuration Shape Optimization Project

    Data.gov (United States)

    National Aeronautics and Space Administration — CFD-based design-oriented (DO) steady/unsteady aerodynamic analysis tools for Aeroelastic / Aeroservoelastic (AE/ASE) evaluation lag significantly behind other...

  15. Features of infrasonic and ionospheric disturbances generated by launch vehicle

    International Nuclear Information System (INIS)

    In this paper we present a model, which describe the propagation of acoustic pulses through a model terrestrial atmosphere produced by launch vehicle, and effects of these pulses on the ionosphere above the launch vehicle. We show that acoustic pulses generate disturbances of electron density. The value of these disturbances is about 0.04-0.7% of background electron density. So such disturbances can not create serious noise-free during monitoring of explosions by ionospheric method. We calculated parameters of the blast wave generated at the ionospheric heights by launch vehicle. It was shown that the blast wave is intense and it can generates disturbance of electron density which 2.6 times as much then background electron density. This disturbance is 'cord' with diameter about 150-250 m whereas length of radio line is hundreds and thousand km. Duration of ionospheric disturbances are from 0.2 s to 3-5 s. Such values of duration can not be observed during underground and surface explosions. (author)

  16. Performance analysis of a semi-active railway vehicle suspension featuring MR dampers

    Science.gov (United States)

    Kim, Hwan-Choong; Choi, Seung-Bok; Lee, Gyu-Seop; An, Chae-Hun; You, Won-Hee

    2014-03-01

    This paper presents performance analysis of semi-active railway vehicle suspension system using MR damper. In order to achieve this goal, a mathematical dynamic model of railway vehicle is derived by integrating car body, bogie frame and wheel-set which can be able to represent lateral, yaw and roll motion. Based on this model, the dynamic range of MR damper at the railway secondary suspension system and design parameters of MR damper are calculated. Subsequently, control performances of railway vehicle including car body lateral motion and acceleration of MR damper are evaluated through computer simulations. Then, the MR damper is manufactured to be retrofitted with the real railway vehicle and its characteristics are experimentally measured. Experimental performance of MR damper is assessed using test rig which is composed of a car body and two bogies.

  17. Vehicle Detection in Still Images by Using Boosted Local Feature Detector

    Institute of Scientific and Technical Information of China (English)

    Qing LIN; Young-joon HAN; Hern-soo HAHN

    2010-01-01

    Vehicle detection in still images is a comparatively difficult task.This paper presents a method for this task by using boosted local pattem detector constructed from two local features including Haar-like and oriented gradient features.The whole process is composed of three stages.In the first stage,local appearance features of vehicles and non-vehicle objects are extracted.Haar-like and oriented gradient features arc extracted separately in this stage as local features.In the second stage,Adaboost algorithm is used to select the mast discriminative features as weak detectors from the two local feature sets,and a strong local pattern detector is built by the weighted combination of these selected weak detectors.Finally,vehicle detection can be performed in still images by using the boosted strong local feature detector.Experiment results show that the local pattern detectur constructed in this way combines the advantages of Haar-like and oriented gradient features,and can achieve better detection results than the datector by using single Haar-like features.

  18. A New Application of Multi-Body System Dynamics in Vehicle-Road Interaction Simulation

    Institute of Scientific and Technical Information of China (English)

    RenWei-qun; ZhangYun-qing; JinGuo-dong

    2003-01-01

    In vehicle-road interaction simulation, multibody system (MBS) dynamics as well as the corresponding software ADAMS has been employed to model the nonlinear vehicle in more detail. The simulation method has been validated by the test data, and been compared to the former simple models. This method can be used for estimating the effects of dynamic tire forces and other vehicle features on road damage so that the “road-friendliness” can be assessed in vehicle design process.

  19. A STUDY ON BODY COMPOSITION, BODY COMPONENTS AND SOMATOTYPE CHARACTERISTICS OF SOCCER PLAYERS

    OpenAIRE

    Kürkçü, Recep; Hazar, Fatih; Özdağ, Selçuk

    2009-01-01

    The aim of this study is to study to determine and comparison the body composition, body components and somatotype characteristics of young soccer players (Young Soccer Team of Sport Club of Muğla University) with other national and international soccer players. Subjects were eighteen pubescent soccer players (age, 13.22y) of a team playing in regional soccer league. Skinfolds (biceps, triceps, back, suprailiac, abdominal, leg, thigh), diameters (femur and humerus biconduler), circumferences ...

  20. Ceres' deformational surface features compared to other planetary bodies.

    Science.gov (United States)

    von der Gathen, Isabel; Jaumann, Ralf; Krohn, Katrin; Buczkowski, Debra L.; Elgner, Stephan; Kersten, Elke; Matz, Klaus-Dieter; Nass, Andrea; Otto, Katharina; Preusker, Frank; Roatsch, Thomas; Schröder, Stefanus E.; Schulzeck, Franziska; Stephan, Katrin; Wagner, Roland; De Sanctis, Maria C.; Schenk, Paul; Scully, Jennifer E. C.; Williams, Dave A.; Raymond, Carol A.

    2016-04-01

    On March 2015, NASA's Dawn spacecraft arrived at the dwarf planet Ceres and has been providing images of its surface. Based on High Altitude Mapping Orbiter (HAMO) clear filter images (140 m/px res.), a Survey mosaic (~400 m/px) and a series of Low Altitude Mapping Orbiter (LAMO) clear filter images (35 m/px) of the Dawn mission [1], deformational features are identified on the surface of Ceres. In order to further our knowledge about the nature and origin of these features, we start a comparative analysis of similar features on different planetary bodies, like Enceladus, Ganymede and the Moon, based on images provided by the Cassini, Galileo and Lunar Orbiter mission. This study focuses on the small scale fractures, mostly located on Ceres' crater floors, in comparison with crater fractures on the planetary bodies named above. The fractures were analyzed concerning the morphology and shape, the distribution, orientation and possible building mechanisms. On Ceres, two different groups of fractures are distinct. The first one includes fractures, normally arranged in subparallel pattern, which are usually located on crater floors, but also on crater rims. Their sense of direction is relatively uniform but in some cases they get deformed by shearing. The second group consists of joint systems, which spread out of one single location, sometimes arranged concentric to the crater rim. They were likely formed by cooling-melting processes linked to the impact process or up doming material. Fractures located on crater floors are also common on the icy satellite Enceladus [3]. While Enceladus' fractures don't seem to have a lot in common compared to those on Ceres, we assume that similar fracture patterns and therefore similar building mechanism can be found e.g. on Ganymede and especially on the Moon [2]. Further work will include the comparison of the fractures with additional planetary bodies and the trial to explain why fracturing e.g. on Enceladus differs from that on

  1. Low-order modeling of wind farm aerodynamics using leaky Rankine bodies

    OpenAIRE

    Araya, Daniel B.; Craig, Anna E.; Kinzel, Matthias; Dabiri, John O.

    2014-01-01

    We develop and characterize a low-order model of the mean flow through an array of vertical-axis wind turbines (VAWTs), consisting of a uniform flow and pairs of potential sources and sinks to represent each VAWT. The source and sink in each pair are of unequal strength, thereby forming a “leaky Rankine body” (LRB). In contrast to a classical Rankine body, which forms closed streamlines around a bluff body in potential flow, the LRB streamlines have a qualitatively similar appearance to a sep...

  2. Air-Breathing Hypersonic Vehicle Aerodynamic Coupling Interference Effects%吸气式高超声速飞行器气动耦合干扰效应研究

    Institute of Scientific and Technical Information of China (English)

    欧岳峰; 方群; 王乐

    2011-01-01

    As there are many intense coupling characteristics between fuselage and scramjet, which inevitably has a significant impact on aircraft design, control system design and analysis of aircraft dynamics.Therefore, it is essential to carry out deep research on aerodynamic coupling interference effects between fuselage and scramjet.First of all, inviscid aerodynamic characteristics calculation of various components of hypersonic vehicle is conducted, and then aerodynamic coupling interference effects between fuselage and scramjet are carried out by exhaust plume model.Finally, simulation and verification are conducted based on vehicle parametric model.Results show that exhaust plume analysis model can accurately reflect the interference characteristics between fuselage and scramjet, which provides the basis for the fuselage / engine integrated design, control system design and dynamic characteristics of analysis of Air-breathing hypersonic vehicle.%研究飞行器与冲压发动机耦合干扰效率优化问题,由于吸气式高超声速飞行器机身与冲压发动机之间存在高度耦合,针对耦合效应不可避免对飞行器稳定性产生影响,为提高控制系统性能,提出飞行器机身与发动机之间的耦合干扰效应问题展开深入研究.在高超声速飞行器各部件无粘气动特性的基础上,采用尾气羽流分析模型研究机身与冲压发动机耦合干扰效应,并基于飞行器几何参数化模型进行仿真.结果表明分析模型能较精确地快速反应机身与冲压发动机之间耦合干扰效应,为吸气式高超声速飞行器机身/发动机一体化设计和控制系统优化设计及其动力学特性研究分析提供依据.

  3. Variance components for body weight in Japanese quails (Coturnix japonica

    Directory of Open Access Journals (Sweden)

    RO Resende

    2005-03-01

    Full Text Available The objective of this study was to estimate the variance components for body weight in Japanese quails by Bayesian procedures. The body weight at hatch (BWH and at 7 (BW07, 14 (BW14, 21 (BW21 and 28 days of age (BW28 of 3,520 quails was recorded from August 2001 to June 2002. A multiple-trait animal model with additive genetic, maternal environment and residual effects was implemented by Gibbs sampling methodology. A single Gibbs sampling with 80,000 rounds was generated by the program MTGSAM (Multiple Trait Gibbs Sampling in Animal Model. Normal and inverted Wishart distributions were used as prior distributions for the random effects and the variance components, respectively. Variance components were estimated based on the 500 samples that were left after elimination of 30,000 rounds in the burn-in period and 100 rounds of each thinning interval. The posterior means of additive genetic variance components were 0.15; 4.18; 14.62; 27.18 and 32.68; the posterior means of maternal environment variance components were 0.23; 1.29; 2.76; 4.12 and 5.16; and the posterior means of residual variance components were 0.084; 6.43; 22.66; 31.21 and 30.85, at hatch, 7, 14, 21 and 28 days old, respectively. The posterior means of heritability were 0.33; 0.35; 0.36; 0.43 and 0.47 at hatch, 7, 14, 21 and 28 days old, respectively. These results indicate that heritability increased with age. On the other hand, after hatch there was a marked reduction in the maternal environment variance proportion of the phenotypic variance, whose estimates were 0.50; 0.11; 0.07; 0.07 and 0.08 for BWH, BW07, BW14, BW21 and BW28, respectively. The genetic correlation between weights at different ages was high, except for those estimates between BWH and weight at other ages. Changes in body weight of quails can be efficiently achieved by selection.

  4. Aerodynamic Shutoff Valve

    Science.gov (United States)

    Horstman, Raymond H.

    1992-01-01

    Aerodynamic flow achieved by adding fixed fairings to butterfly valve. When valve fully open, fairings align with butterfly and reduce wake. Butterfly free to turn, so valve can be closed, while fairings remain fixed. Design reduces turbulence in flow of air in internal suction system. Valve aids in development of improved porous-surface boundary-layer control system to reduce aerodynamic drag. Applications primarily aerospace. System adapted to boundary-layer control on high-speed land vehicles.

  5. Comparative tectonic features on Ceres and other planetary bodies

    Science.gov (United States)

    Roatsch, T.; von der Gathen, I.; Jaumann, R.; Krohn, K.; Otto, K.; Schulzeck, F.; Williams, D. A.; Buczkowski, D.; De Sanctis, M. C.; Elgner, S.; Kersten, E.; Matz, K. D.; Naß, A.; Preusker, F.; Schenk, P.; Schroeder, S.; Stephan, K.; Wagner, R. J.; Raymond, C. A.; Russell, C. T.

    2015-12-01

    Dawn Framing Camera images of Ceres' surface indicate that tectonic processes have played an important role in the surface formation history and alterations. We study structures expected to be the result of tectonic deformation and crustal stresses, which may enable us to reconstruct the formation process of the surface and the topographic signature. Tectonic features on Ceres such as troughs, ridges, scarps, fractures, depressions and domes are analogous to those on other planetary bodies like Enceladus, Ganymede, Europa and Mercury. Comparing these surface features will provide additional information about possible scenarios of crustal formation on Ceres. First investigations show that craters, like Urvara (46°S and 249°E), display sets of trenches radiating from the craters interior. They were likely formed by extensional tectonics linked to the impact. Similar features were also found on Mercury's surface. It is expected that other tectonic deformations on Ceres also influence the appearance of craters and crater walls. Comparatively small scale fissures on Ceres' surface, frequently arranged subparallel, seem to appear in terrain that looks smooth in the images. Fractures, cracks and scarps on Ceres can be found on Enceladus, Europa and Mercury in similar patterns. The "tiger stripes" on Enceladus are possible large scale analogous. Ridges on Europa, Enceladus and Ganymede are lineaments that dominate their entire surface. Those on Ceres' however, are more irregularly shaped and less distinct. On Ceres surface troughs seem to be relatively rare. However, they show similarities to troughs on Enceladus and Mercury, and could also be related to those on Europa and Ganymede. Domes are distributed over Ceres' entire surface and have a relatively regular shape. Analogous exist on Europa (relatively irregular or with halos) and Ganymede in the crater interiors.

  6. Kinematic features of whole-body reaching movements underwater: Neutral buoyancy effects.

    Science.gov (United States)

    Macaluso, T; Bourdin, C; Buloup, F; Mille, M-L; Sainton, P; Sarlegna, F R; Taillebot, V; Vercher, J-L; Weiss, P; Bringoux, L

    2016-07-01

    Astronauts' training is conventionally performed in a pool to reproduce weightlessness by exploiting buoyancy which is supposed to reduce the impact of gravity on the body. However, this training method has not been scientifically validated yet, and requires first to study the effects of underwater exposure on motor behavior. We examined the influence of neutral buoyancy on kinematic features of whole-body reaching underwater and compared them with those produced on land. Eight professional divers were asked to perform arm reaching movements toward visual targets while standing. Targets were presented either close or far from the subjects (requiring in the latter case an additional whole-body displacement). Reaching movements were performed on land or underwater in two different contexts of buoyancy. The divers either wore a diving suit only with neutral buoyancy applied to their center of mass or were additionally equipped with a submersible simulated space suit with neutral buoyancy applied to their body limbs. Results showed that underwater exposure impacted basic movement features, especially movement speed which was reduced. However, movement kinematics also differed according to the way buoyancy was exerted on the whole-body. When neutral buoyancy was applied to the center of mass only, some focal and postural components of whole-body reaching remained close to land observations, notably when considering the relative deceleration duration of arm elevation and concomitant forward trunk bending when reaching the far target. On the contrary, when neutral buoyancy was exerted on body segments, movement kinematics were close to those reported in weightlessness, as reflected by the arm deceleration phase and the whole-body forward displacement when reaching the far target. These results suggest that astronauts could benefit from the application of neutral buoyancy across the whole-body segments to optimize underwater training and acquire specific motor skills which

  7. Aerodynamic study, design and construction of a Blended Wing Body (BWB) Unmanned Aircraft (UA)

    OpenAIRE

    De Toro Diaz, Aleix

    2015-01-01

    During this project a Blended Wing Body (BWB) UA (Unmanned Aircraft) model is built. BWBs are a combination of a common airplane with tail control surfaces and a flying wing. BWBs lack tail control surfaces, which makes its design to be very different and more complex regarding stability. To first start the BWB design, some research has been done about the basic parameters of the BWB designs. Moreover, different airfoils are considered to improve the stability of the UA. Two designs are creat...

  8. Hysteresis zone or locus - Aerodynamic of bulbous based bodies at low speeds

    Science.gov (United States)

    Covert, E. E.

    1979-01-01

    Experimental data are presented which seem to suggest that a well-defined hysteresis locus on bulbous based bodies at low speeds does not exist. Instead, if the experiment is repeated several times, the entire hysteresis region seems to fill with data rather than trace out a specific hysteresis locus. Data obtained on an oscillating model even at low reduced frequencies may be well defined but when applied to arbitrary motion lead to less accurate results than desired.

  9. Sharp Hypervelocity Aerodynamic Research Probe

    Science.gov (United States)

    Bull, Jeffrey; Kolodziej, Paul; Rasky, Daniel J. (Technical Monitor)

    1996-01-01

    The objective of this flight demonstration is to deploy a slender-body hypervelocity aerodynamic research probe (SHARP) from an orbiting platform using a tether, deorbit and fly it along its aerothermal performance constraint, and recover it intact in mid-air. To accomplish this objective, two flight demonstrations are proposed. The first flight uses a blunt-body, tethered reentry experiment vehicle (TREV) to prove out tethered deployment technology for accurate entries, a complete SHARP electronics suite, and a new soft mid-air helicopter recovery technique. The second flight takes advantage of this launch and recovery capability to demonstrate revolutionary sharp body concepts for hypervelocity vehicles, enabled by new Ultra-High Temperature Ceramics (UHTCs) recently developed by Ames Research Center. Successful demonstration of sharp body hypersonic vehicle technologies could have radical impact on space flight capabilities, including: enabling global reentry cross range capability from Station, eliminating reentry communications blackout, and allowing new highly efficient launch systems incorporating air breathing propulsion and zeroth staging.

  10. 横风作用下公路车辆与桥梁静气动力的数值模拟研究%Numerical simulation on static aerodynamic forces of vehicles and bridges under cross winds

    Institute of Scientific and Technical Information of China (English)

    韩艳; 胡揭玄; 蔡春声

    2012-01-01

    The exact identification of the aerodynamic parameters of vehicles and bridges needed for the coupling vibration analysis of the wind - vehicle - bridge system. The model of bridge and the model of coupled system of bridges and vehicles were built and the static aerodynamic forces of bridges and vehicles at different wind attack angles in high and low turbulence wind fields were calculated by the method of computational fliud dynamics (CFD) in this paper. The influence of vehicles on the static aerodynamic forces of bridge, the influence of wind attack angles on the static aerodynamic forces of vehicle and the influence of turbulent characteristics on the static aerodynamic forces of vehicle and bridge were investigated. The results show that the static aerodynamic forces of bridge at different wind attack angles are larger due to the interference of the vehicle. The wind attack angles have great influence on the static aerodynamic force/moment coefficients of the vehicle. The turbulence has some influence on the force/moment coefficients, but almost has no influence on those of the bridge.%横风作用下的风—车—桥耦合系统的振动分析需要准确识别车辆和桥梁气动参数.基于CFD数值仿真平台分别建立了桥梁单体模型和车桥耦合体系模型,计算分析了高低紊流度风场中不同风攻角下车辆和桥梁的静气动力,分析研究了静止车辆对桥梁静气动力的影响、风攻角对车辆静气动力的影响以及风场的紊流性对车桥静气动力的影响.计算结果表明:由于车辆的干扰,不同风攻角下的桥梁静气动力普遍增大;风攻角对车辆静气动力系数影响比较大;紊流特性对车辆静气动力系数有一定影响,对桥梁静气动力系数影响不大.

  11. Vehicle detection from high-resolution aerial images based on superpixel and color name features

    Science.gov (United States)

    Chen, Ziyi; Cao, Liujuan; Yu, Zang; Chen, Yiping; Wang, Cheng; Li, Jonathan

    2016-03-01

    Automatic vehicle detection from aerial images is emerging due to the strong demand of large-area traffic monitoring. In this paper, we present a novel framework for automatic vehicle detection from the aerial images. Through superpixel segmentation, we first segment the aerial images into homogeneous patches, which consist of the basic units during the detection to improve efficiency. By introducing the sparse representation into our method, powerful classification ability is achieved after the dictionary training. To effectively describe a patch, the Histogram of Oriented Gradient (HOG) is used. We further propose to integrate color information to enrich the feature representation by using the color name feature. The final feature consists of both HOG and color name based histogram, by which we get a strong descriptor of a patch. Experimental results demonstrate the effectiveness and robust performance of the proposed algorithm for vehicle detection from aerial images.

  12. 碟形升力体低速气动性能风洞试验研究%Low-speed Aerodynamic Performance Wind Tunnel Tests of the Saucer-shaped Lifting Body

    Institute of Scientific and Technical Information of China (English)

    王林林; 高歌

    2013-01-01

    升力体布局常见于航天器的设计中,在低速领域较少应用;但其紧凑的布局,巨大的升力体面积,充足的载物空间,翼身一体化的设计思想,都使具有在种类繁多、功能多样的无人机领域获得广泛应用的潜力.设计了一种碟形升力体,并对其低速气动性能进行了风洞试验研究,获得了其升力、阻力、升阻比特性和静稳定特性的试验数据,并对其进行了分析.试验结构表明,碟形升力体具有较好的气动性能,已经具备一定的实用性.还以碟形升力体的研究结论为依据,对低速升力体的特点及其在无人机领域的应用前景进行了分析和论述.%The lifting body aircraft is usually used in the spacecraft design,rarely used in the low speed condition.With the compact layout,huge lift surface,sufficient payload space and the wing-fuselage integration,the lifting body aircraft has the potential of being widely adopted for the various unmanned aerial vehicle designs.A saucer-shaped lifting body was designed,and its low speed aerodynamic performance including lift,drag,lift to drag ratio,and the static stability,were investigated by wind tunnel tests.Analyses of the wind tunnel tests results were done.The analyses prove that the saucer-shaped lifting body has a good aerodynamic performance.The application of low speed lifting body in unmanned aerial vehicle field is also discussed based on the investigation conclusions of the sauce-shaped lifting body.

  13. Feature extraction for ultrasonic sensor based defect detection in ceramic components

    Science.gov (United States)

    Kesharaju, Manasa; Nagarajah, Romesh

    2014-02-01

    High density silicon carbide materials are commonly used as the ceramic element of hard armour inserts used in traditional body armour systems to reduce their weight, while providing improved hardness, strength and elastic response to stress. Currently, armour ceramic tiles are inspected visually offline using an X-ray technique that is time consuming and very expensive. In addition, from X-rays multiple defects are also misinterpreted as single defects. Therefore, to address these problems the ultrasonic non-destructive approach is being investigated. Ultrasound based inspection would be far more cost effective and reliable as the methodology is applicable for on-line quality control including implementation of accept/reject criteria. This paper describes a recently developed methodology to detect, locate and classify various manufacturing defects in ceramic tiles using sub band coding of ultrasonic test signals. The wavelet transform is applied to the ultrasonic signal and wavelet coefficients in the different frequency bands are extracted and used as input features to an artificial neural network (ANN) for purposes of signal classification. Two different classifiers, using artificial neural networks (supervised) and clustering (un-supervised) are supplied with features selected using Principal Component Analysis(PCA) and their classification performance compared. This investigation establishes experimentally that Principal Component Analysis(PCA) can be effectively used as a feature selection method that provides superior results for classifying various defects in the context of ultrasonic inspection in comparison with the X-ray technique.

  14. A ballistic investigation of the aerodynamic characteristics of a blunt vehicle at hypersonic speeds in carbon dioxide and air

    Science.gov (United States)

    Packard, James D.; Griffith, Wayland C.; Yates, Leslie A.; Strawa, Anthony W.

    1992-01-01

    Missions to Mars require the successful development of aerobraking technology, and therefore a blunt cone representative of aerobrake shapes is investigated. Ballistic tests of the Pioneer Venus configuration are conducted in carbon dioxide and air at Mach numbers from 7 to 20 and Reynolds numbers from 0.1 x 10 exp 5 to 4 x 10 exp 6. Experimental results show that for defined conditions aerodynamic research can be conducted in air rather than carbon dioxide, providing savings in time and money. In addition, the results offer a prediction of flight aerodynamics during entry into the Martian atmosphere. Also discussed is a comparison of results from two data-reduction techniques showing that a five-degree-of-freedom routine employing weighted least-squares with differential corrections analyzes ballistic data more accurately.

  15. An Advanced Open-Source Aircraft Design Platform for Personal Air Vehicle Geometry, Aerodynamics, and Structures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Innovators working to revolutionize air travel through personal aviation pioneers need innovative aircraft design tools. Vehicle Sketch Pad (VSP) is an aircraft...

  16. Energy-consumption and carbon-emission analysis of vehicle and component manufacturing.

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, J. L.; Burnham, A.; Wang, M.; Energy Systems

    2010-10-12

    A model is presented for calculating the environmental burdens of the part manufacturing and vehicle assembly (VMA) stage of the vehicle life cycle. The approach is bottom-up, with a special focus on energy consumption and CO{sub 2} emissions. The model is applied to both conventional and advanced vehicles, the latter of which include aluminum-intensive, hybrid electric, plug-in hybrid electric and all-electric vehicles. An important component of the model, a weight-based distribution function of materials and associated transformation processes (casting, stamping, etc.), is developed from the United States Council for Automotive Research Generic Vehicle Life Cycle Inventory Study. As the approach is bottom-up, numerous transformation process data and plant operational data were extracted from the literature for use in representing the many operations included in the model. When the model was applied to conventional vehicles, reliable estimates of cumulative energy consumption (34 GJ/vehicle) and CO{sub 2} emission (2 tonnes/vehicle) were computed for the VMA life-cycle stage. The numerous data sets taken from the literature permitted the development of some statistics on model results. Because the model explicitly includes a greater coverage of relevant manufacturing processes than many earlier studies, our energy estimates are on the higher end of previously published values. Limitations of the model are also discussed. Because the material compositions of conventional vehicles within specific classes (cars, light duty trucks, etc.) are sensibly constant on a percent-by-weight basis, the model can be reduced to a simple linear form for each class dependent only on vehicle weight. For advanced vehicles, the material/transformation process distribution developed above needs to be adjusted for different materials and components. This is particularly so for aluminum-intensive and electric-drive vehicles. In fact, because of their comparatively high manufacturing

  17. Aerodynamic performance and particle image velocimetery of piezo actuated biomimetic manduca sexta engineered wings towards the design and application of a flapping wing flight vehicle

    Science.gov (United States)

    DeLuca, Anthony M.

    Considerable research and investigation has been conducted on the aerodynamic performance, and the predominate flow physics of the Manduca Sexta size of biomimetically designed and fabricated wings as part of the AFIT FWMAV design project. Despite a burgeoning interest and research into the diverse field of flapping wing flight and biomimicry, the aerodynamics of flapping wing flight remains a nebulous field of science with considerable variance into the theoretical abstractions surrounding aerodynamic mechanisms responsible for aerial performance. Traditional FWMAV flight models assume a form of a quasi-steady approximation of wing aerodynamics based on an infinite wing blade element model (BEM). An accurate estimation of the lift, drag, and side force coefficients is a critical component of autonomous stability and control models. This research focused on two separate experimental avenues into the aerodynamics of AFIT's engineered hawkmoth wings|forces and flow visualization. 1. Six degree of freedom force balance testing, and high speed video analysis was conducted on 30°, 45°, and 60° angle stop wings. A novel, non-intrusive optical tracking algorithm was developed utilizing a combination of a Gaussian Mixture Model (GMM) and ComputerVision (OpenCV) tools to track the wing in motion from multiple cameras. A complete mapping of the wing's kinematic angles as a function of driving amplitude was performed. The stroke angle, elevation angle, and angle of attack were tabulated for all three wings at driving amplitudes ranging from A=0.3 to A=0.6. The wing kinematics together with the force balance data was used to develop several aerodynamic force coefficient models. A combined translational and rotational aerodynamic model predicted lift forces within 10%, and vertical forces within 6%. The total power consumption was calculated for each of the three wings, and a Figure of Merit was calculated for each wing as a general expression of the overall efficiency of

  18. A STUDY ON BODY COMPOSITION, BODY COMPONENTS AND SOMATOTYPE CHARACTERISTICS OF SOCCER PLAYERS

    Directory of Open Access Journals (Sweden)

    Recep KÜRKÇÜ

    2009-08-01

    Full Text Available The aim of this study is to study to determine and comparison the body composition, body components and somatotype characteristics of young soccer players (Young Soccer Team of Sport Club of Muğla University with other national and international soccer players. Subjects were eighteen pubescent soccer players (age, 13.22y of a team playing in regional soccer league. Skinfolds (biceps, triceps, back, suprailiac, abdominal, leg, thigh, diameters (femur and humerus biconduler, circumferences (biceps, thigh of the body and body fat parameters were measured. Somatotype characteristics were calculated and evaluated by Heat-Carter formula. Subjects’ measurements were as; height 158.44±10.42cm, body weight 47.65±8.38kg, skinfolds; biceps 5.75±1.54mm, triceps 10.61±2.93mm, back 7.30±1.59mm, suprailiac 7.00±2.04mm, abdominal 9.91±3.98mm, leg 13.52±4.76mm; diameters; femur biconduler 11.03±0.74cm; humerus biconduler 7.30±0.59cm; circumferences, biceps 22.76±3.11cm, thigh 32.84±3.33cm and body fat percentage 5.41±1.37 %, somatotype characteristics; Endomorph; 4.59±2.08, Mezomorph; 6.94±3.10, and Ecthomorph; 3.55±1.34. In related sports, physical fitness parameters including physical and anthropometric characteristics of athletes are very important in talent identification. Therefore, results of the present study could provide important data on selection of talented players in soccer and to the other related researches.

  19. In-service weld repairs of valve bodies and components

    International Nuclear Information System (INIS)

    The idea of performing welding and machining to valve bodies in line, has only come of age within the last five to seven years. Although many plants currently use this technology, many limit its use to light machine cuts, lapping or polishing of seats and/or gasket faces. It's no secret, over the past ten years technology has advanced rapidly. The technological resources available today, in this specialized industry, are practically incalculable. Suppliers are stocking fewer parts, thus generating longer lead times. As a result, the need to repair has overwhelmed the desire to replace. Technological advances in machine welding processes and specialized machine tooling have turned what was once considered science, into reality. Over the past few years these type services have greatly improved the quality of repairs and the time it takes to complete them. As in any new technology there are typically some concerns. They may range from, ''Did I get a sound repair or a Band-Aid fix?'' to ''Was it really cost effective?'' There are only a few requirements one needs to follow: (1) define the Work Scope ''detail''; (2) qualify a vendor; (3) perform mockup; (4) be ready for the unexpected. The idea behind this Paper is to show its readers that in line repairs require considerable planning, communication, teamwork, capable personnel, and state-of-the-art equipment. The advantage of an in line valve repair versus removing it from its in line location is simply, cost effectiveness. Occasionally, environmental factors may even prohibit such removal. Additionally, it is not unusual for valve replacement to become critical path during an outage. In summary, the author intends to elaborate on the full potential and benefits of in line repairs to valve bodies and related components

  20. Mood Recognition Based on Upper Body Posture and Movement Features

    NARCIS (Netherlands)

    Thrasher, M.L.; Van der Zwaag, M. D.; Bianchi-Berthouze, N.; Westerink, J.H.D.M.

    2012-01-01

    While studying body postures in relation to mood is not a new concept, the majority of these studies rely on actors interpretations. This project investigated the temporal aspects of naturalistic body postures while users listened to mood inducing music. Video data was collected while participants l

  1. Features of encounters of small bodies with planets

    Science.gov (United States)

    Emel'yanenko, N. Yu.

    2015-11-01

    A kinematic approach is developed to qualitative analysis of characteristics of a low-speed encounter of a small body with a planet. A classification of encounters of small bodies with planets based on the magnitude of planetocentric speed is proposed. The concept of the points of low-speed quasi-tangency of orbits of small bodies and planets is introduced. Based on this concept, the definitions of the point of minimum planetocentric speed, a quasi-tangent low-velocity segment on the orbit of a small body, low-velocity and high-velocity encounters are formulated. A classification of encounters of small bodies with planets according to the global minimum of the function of planetocentric distance is also proposed. The classification is based on the concepts of the gravity sphere of action and the Hill sphere of the planet. The definitions of an area and duration of low-speed and high-speed encounters are given.

  2. ZEUS-DO: A Design Oriented CFD-Based Unsteady Aerodynamic Capability for Flight Vehicle Multidisciplinary Configuration Shape Optimization Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In practically all air-vehicle MDO studies to date involving configuration shape optimization, dynamic Aeroservoelastic constraints had to be left out. Flutter,...

  3. Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS): features and potential applications in oncology

    Energy Technology Data Exchange (ETDEWEB)

    Kwee, Thomas C.; Takahara, Taro; Nievelstein, Rutger A.J.; Luijten, Peter R. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Ochiai, Reiji [Koga Hospital 21, Department of Radiology, Kurume (Japan)

    2008-09-15

    Diffusion-weighted magnetic resonance imaging (DWI) provides functional information and can be used for the detection and characterization of pathologic processes, including malignant tumors. The recently introduced concept of ''diffusion-weighted whole-body imaging with background body signal suppression'' (DWIBS) now allows acquisition of volumetric diffusion-weighted images of the entire body. This new concept has unique features different from conventional DWI and may play an important role in whole-body oncological imaging. This review describes and illustrates the basics of DWI, the features of DWIBS, and its potential applications in oncology. (orig.)

  4. Mood Recognition Based on Upper Body Posture and Movement Features

    OpenAIRE

    Thrasher, M.L.; Van der Zwaag, M.D.; Bianchi-Berthouze, N.; Westerink, J.H.D.M.

    2012-01-01

    While studying body postures in relation to mood is not a new concept, the majority of these studies rely on actors interpretations. This project investigated the temporal aspects of naturalistic body postures while users listened to mood inducing music. Video data was collected while participants listened to eight minutes of music duringtwo sessions (happy and sad) in a within-subjects design. Subjectively reported mood scores validated that mood did differ significantly for valence and ener...

  5. Enery Efficient Press and Sinter of Titanium Powder for Low-Cost Components in Vehicle Applications

    Energy Technology Data Exchange (ETDEWEB)

    Thomas Zwitter; Phillip Nash; Xiaoyan Xu; Chadwick Johnson

    2011-03-31

    This is the final technical report for the Department of Energy NETL project NT01931 Energy Efficient Press and Sinter of Titanium Powder for Low-Cost Components in Vehicle Applications. Titanium has been identified as one of the key materials with the required strength that can reduce the weight of automotive components and thereby reduce fuel consumption. Working with newly developed sources of titanium powder, Webster-Hoff will develop the processing technology to manufacture low cost vehicle components using the single press/single sinter techniques developed for iron based powder metallurgy today. Working with an automotive or truck manufacturer, Webster-Hoff will demonstrate the feasibility of manufacturing a press and sinter titanium component for a vehicle application. The project objective is two-fold, to develop the technology for manufacturing press and sinter titanium components, and to demonstrate the feasibility of producing a titanium component for a vehicle application. The lowest cost method for converting metal powder into a net shape part is the Powder Metallurgy Press and Sinter Process. The method involves compaction of the metal powder in a tool (usually a die and punches, upper and lower) at a high pressure (up to 60 TSI or 827 MPa) to form a green compact with the net shape of the final component. The powder in the green compact is held together by the compression bonds between the powder particles. The sinter process then converts the green compact to a metallurgically bonded net shape part through the process of solid state diffusion. The goal of this project is to expand the understanding and application of press and sinter technology to Titanium Powder applications, developing techniques to manufacture net shape Titanium components via the press and sinter process. In addition, working with a vehicle manufacturer, demonstrate the feasibility of producing a titanium component for a vehicle. This is not a research program, but rather a

  6. [Study on polarization spectral feature of suspended sediment in the water body].

    Science.gov (United States)

    Zhu, Jin; Wang, Xian-Hua; Pan, Bang-Long

    2012-07-01

    Remote sensing of lake water based on water-leaving radiance is to retrieve the concentrations of suspended sediment, phytoplankton and yellow substance which have great impacts on spectrum to assess the water quality. Howerver, because of the complexity of the lake water compositons and the interference between the different components, it is of great difficulty to get accurate results with the reflectance spectrum method developed recently. In the present paper, the authors firstly discussed the reflectance and polarization spectral feature of suspended sediment water body, found out the relations of the reflectance and the degree of polarization of water-leaving radiance and the concentration of suspended sediment at the sensitive bands. The authors also compared the effectiveness of the retrieval approaches based on reflectance and polarization in laboratory water body and Chaohu water body respectively. The results show that in the lake water body where the constituents are very complex, the polarization information has greater capacity of anti-jamming, therefore it will have great potential applictions in lake water quality remote sensing. PMID:23016352

  7. Application of fleet ballistic missile components/designs for expendable launch vehicles

    Science.gov (United States)

    Grizzell, Norman E.

    This paper describes the orbital performance and configuration attributes of an expendable launch vehicle (ELV) derived from flight-qualified components. Representative logistical and programmatic data are also provided. The backbone of the ELV program described is the cost-effective use of proven Fleet Ballistic Missile components/designs coupled with other high confidence 'off-the-shelf' equipment. The ELV defined can place over a thousand pounds (1000 lb) of spacecraft (payload) into Low Earth Orbit.

  8. Development of Three-dimensional Grid-free Solver and its Applications to Multi-body Aerospace Vehicles

    OpenAIRE

    K. Anandhanarayanan

    2010-01-01

    Grid-free solver has the ability to solve complex multi-body industrial problems with minimal effort. Grid-free Euler solver has been applied to number of multi-body aerospace vehicles using Chimera clouds of points including flight vehicle with fin deflection, nose fairing separation of hypersonic launch vehicle. A preprocessor has been developed to generate connectivity for multi-bodies using overlapped grids. Surface transpiration boundary condition has been implemented to model aerodynami...

  9. The application of some lifting-body reentry concepts to missile design

    Science.gov (United States)

    Spearman, M. L.

    1985-01-01

    The aerodynamic characteristics of some lifting-body concepts are examined with a view to the applicability of such concepts to the design of missiles. A considerable amount of research has been done in past years with vehicle concepts suitable for manned atmospheric-entry and atmospheric flight. Some of the concepts appear to offer some novel design approaches for missiles for a variety of missions and flight profiles, including long-range orbital/reentry with transatmospheric operation for strategic penetration, low altitude penetration, and battlefield tactical. The concepts considered include right triangular pyramidal configurations, a lenticular configuration, and various 75-degree triangular planform configurations with variations in body camber and control systems. The aerodynamic features are emphasized but some observations are also made relative to other factors such as heat transfer, structures, carriage, observability, propulsion, and volumetric efficiency.

  10. Body Dysmorphic Disorder: Neurobiological Features and an Updated Model

    OpenAIRE

    Li, Wei; Arienzo, Donatello; Feusner, Jamie D

    2013-01-01

    Body Dysmorphic Disorder (BDD) affects approximately 2% of the population and involves misperceived defects of appearance along with obsessive preoccupation and compulsive behaviors. There is evidence of neurobiological abnormalities associated with symptoms in BDD, although research to date is still limited. This review covers the latest neuropsychological, genetic, neurochemical, psychophysical, and neuroimaging studies and synthesizes these findings into an updated (yet still preliminary) ...

  11. Component- and Alloy-Specific Modeling for Evaluating Aluminum Recycling Strategies for Vehicles

    Science.gov (United States)

    Modaresi, Roja; Løvik, Amund N.; Müller, Daniel B.

    2014-11-01

    Previous studies indicated that the availability of mixed shredded aluminum scrap from end-of-life vehicles (ELV) is likely to surpass the capacity of secondary castings to absorb this type of scrap, which could lead to a scrap surplus unless suitable interventions can be identified and implemented. However, there is a lack of studies analyzing potential solutions to this problem, among others, because of a lack of component- and alloy-specific information in the models. In this study, we developed a dynamic model of aluminum in the global vehicle stock (distinguishing 5 car segments, 14 components, and 7 alloy groups). The forecasts made up to the year 2050 for the demand for vehicle components and alloy groups, for the scrap supply from discarded vehicles, and for the effects of different ELV management options. Furthermore, we used a source-sink diagram to identify alloys that could potentially serve as alternative sinks for the growing scrap supply. Dismantling the relevant components could remove up to two-thirds of the aluminum from the ELV stream. However, the use of these components for alloy-specific recycling is currently limited because of the complex composition of components (mixed material design and applied joining techniques), as well as provisions that practically prevent the production of safety-relevant cast parts from scrap. In addition, dismantling is more difficult for components that are currently penetrating rapidly. Therefore, advanced alloy sorting seems to be a crucial step that needs to be developed over the coming years to avoid a future scrap surplus and prevent negative energy use and emission consequences.

  12. Autonomous Feature Following for Visual Surveillance Using a Small Unmanned Aerial Vehicle with Gimbaled Camera System

    OpenAIRE

    Lee, Deok-Jin; Kaminer, Isaac; Dobrokhodov, Vladimir; Jones, Kevin

    2010-01-01

    The article of record as published may be located at http://dx.doi.org/10.1007/s12555-010-0504-1 This paper represents the development of feature following control and distributed navigation algorithms for visual surveillance using a small unmanned aerial vehicle equipped with a low-cost imaging sensor unit. An efficient map-based feature generation and following control algorithm is developed to make an onboard imaging sensor to track a target. An efficient navigation system is a...

  13. The Effect of Different Rail Heights on Aerodynamic Performance of Straddle Type Monorail Vehicles%不同轨面高度对跨坐式单轨车气动性能的影响

    Institute of Scientific and Technical Information of China (English)

    杜子学; 张杰; 赵科

    2011-01-01

    Based on the head model of Straddle-type Monorail Vehicle,by application of numerical simulation method and by setting different computing domains, the height of straddle type monorail vehicle of the orbital plane and ground is simulated and the impact of different orbital plane height on the aerodynamic performance under the windward condition is analyzed. The results of the analyses show that as the rail surface height increases, the monorail vehicle's aerodynamic performance improves along with it and at the height of 6m above, aerodynamic performance changes of monorail vehicle tend to smooth. But there is a little difference in wind resistance under the different orbital plane height. This indicates that the change in orbital plane height has a little effect on its aerodynamic performance. The orbital plane height setting of Chongqing straddle type monorail vehicle for orbital plane heights of different sections is reasonable.%基于踌坐武单轨车头车模型,运用数值模拟方法,通过设置不同的计算域来模拟跨坐式单轨车轨面与地面的高度,分析在迎风条件下不同轨面高度对其气动性能的影响.分析结果表明:随着轨面高度的增加,单轨车的气动性能随之改善,且在离地高度6m以上单轨车的气动性能变化趋于平缓.但不同轨面高度下的风阻值差异较小,这表明单轨车轨面高度的变化对其气动性能影响较小,重庆跨坐式单轨车不同路段轨面高度的设置是合理的.

  14. Near Term Hybrid Passenger Vehicle Development Program. Phase I, Final report. Appendix C: preliminary design data package. Volume II. Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Piccolo, R.

    1979-09-11

    This appendix to the final report on the Hybrid Passenger Vehicle Development Program contans data on Na-S batteries, Ni-Zn batteries; vehicle body design; tire characteristics; and results of computer simulations of vehicle yaw, pitch, and roll under various driving and aerodynamic conditions. (LCL)

  15. The changing features of the body-mind problem.

    Science.gov (United States)

    Agassi, Joseph

    2007-01-01

    The body-mind problem invites scientific study, since mental events are repeated and repeatable and invite testable explanations. They seemed troublesome because of the classical theory of substance that failed to solve its own central problems. These are soluble with the aid of the theory of the laws of nature, particularly in its emergentist version [Bunge, M., 1980. The Body-mind Problem, Pergamon, Oxford] that invites refutable explanations [Popper, K.R., 1959. The Logic of Scientific Discovery, Hutchinson, London]. The view of mental properties as emergent is a modification of the two chief classical views, materialism and dualism. As this view invites testable explanations of events of the inner world, it is better than the quasi-behaviorist view of self-awareness as computer-style self-monitoring [Minsky, M., Laske, O., 1992. A conversation with Marvin Minsky. AI Magazine 13 (3), 31-45]. PMID:18261888

  16. Effects of Gas Turbine Component Performance on Engine and Rotary Wing Vehicle Size and Performance

    Science.gov (United States)

    Snyder, Christopher A.; Thurman, Douglas R.

    2010-01-01

    In support of the Fundamental Aeronautics Program, Subsonic Rotary Wing Project, further gas turbine engine studies have been performed to quantify the effects of advanced gas turbine technologies on engine weight and fuel efficiency and the subsequent effects on a civilian rotary wing vehicle size and mission fuel. The Large Civil Tiltrotor (LCTR) vehicle and mission and a previous gas turbine engine study will be discussed as a starting point for this effort. Methodology used to assess effects of different compressor and turbine component performance on engine size, weight and fuel efficiency will be presented. A process to relate engine performance to overall LCTR vehicle size and fuel use will also be given. Technology assumptions and levels of performance used in this analysis for the compressor and turbine components performances will be discussed. Optimum cycles (in terms of power specific fuel consumption) will be determined with subsequent engine weight analysis. The combination of engine weight and specific fuel consumption will be used to estimate their effect on the overall LCTR vehicle size and mission fuel usage. All results will be summarized to help suggest which component performance areas have the most effect on the overall mission.

  17. Shape Design of Lifting body Based on Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Yongyuan Li

    2010-11-01

    Full Text Available This paper briefly introduces the concept and history of lifting body, and puts forward a new method for the optimization of lifting body. This method has drawn lessons from the die line design of airplane is used to parametric numerical modeling for the lifting body, and extract the characterization of shape parameters as design variables, a combination of lifting body reentry vehicle aerodynamic conditions, aerodynamic heating, volumetric Rate and the stability of performance. Multi-objective hybrid genetic algorithm is adopted to complete the aerodynamic shape optimization and design of hypersonic lifting body vehicle when under more variable and constrained condition in order to obtain the Pareto optimal solution of Common Aero Vehicle shape.

  18. Development of Electronic Control Unit For Body Control System of Pure Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Li Hongqiang

    2012-07-01

    Full Text Available This study concerns the design of Electronic Control Units (ECUs for the Body Control System (BCS of Pure Electric Vehicle (PEV. The main research contents are divided into two parts: its CANopen application layer protocol and the model based design of fault detection for anti-pinch window. Firstly, the structure of the BCS and the function of each ECU were analyzed. Then according to the communication needs among the ECUs, the CANopen protocol for each ECU was designed. It contained the design of Network Management, Process Data Objects and Service Data Objects. A CANopen network simulation platform was designed by CANoe software and its components CANoe.CANopen. According to the analysis of anti-pinch window model system, the algorithm based on H-/H∞ fault detection observer estimation is proposed. Apart from the previous methods, the pinch torque rate is considered as a fault under the pinched condition to generate a residual. A residual is zero in normal, but it will deviate from the constant when sensing the pinched condition. Co-simulation model of CANopen protocol and the anti-pinch model based on CANoe-MATLAB and the bench test are design to verify the designed ECUs. The test results show that the bus load rate is 3.49% and the results of detection time are respectively 0.18 and 0.185s, which show the CANopen protocol and the anti-pinch algorithm are proper to the BCS of PEV.

  19. Estimation of the Unsteady Aerodynamic Load on Space Shuttle External Tank Protuberances from a Component Wind Tunnel Test

    Science.gov (United States)

    Panda, Jayatana; Martin, Fred W.; Sutliff, Daniel L.

    2008-01-01

    At the wake of the Columbia (STS-107) accident it was decided to remove the Protuberance Aerodynamic Load (PAL) Ramp that was originally intended to protect various protuberances outside of the Space Shuttle External Tank from high buffet load induced by cross-flows at transonic speed. In order to establish the buffet load without the PAL ramp, a wind tunnel test was conducted where segments of the protuberances were instrumented with dynamic pressure transducers; and power-spectra of sectional lift and drag forces at various span-wise locations between two adjacent support brackets were measured under different cross flow angles, Mach number and other conditions. Additionally, frequency-dependent spatial correlations between the sectional forces were also established. The sectional forces were then adjusted by the correlation length to establish span-averaged spectra of normal and lateral forces that can be suitably "added" to various other unsteady forces encountered by the protuberance. This paper describes the methodology used for calculating the correlation-adjusted power spectrum of the buffet load. A second part of the paper describes wind-tunnel results on the difference in the buffet load on the protuberances with and without the PAL ramp. In general when the ramp height is the same as that of the protuberance height, such as that found on the liquid Oxygen part of the tank, the ramp is found to cause significant reduction of the unsteady aerodynamic load. However, on the liquid Hydrogen part of the tank, where the Oxygen feed-line is far larger in diameter than the height of the PAL ramp, little protection is found to be available to all but the Cable Tray.

  20. Anomaly Detection in Gamma-Ray Vehicle Spectra with Principal Components Analysis and Mahalanobis Distances

    International Nuclear Information System (INIS)

    The goal of primary radiation monitoring in support of routine screening and emergency response is to detect characteristics in vehicle radiation signatures that indicate the presence of potential threats. Two conceptual approaches to analyzing gamma-ray spectra for threat detection are isotope identification and anomaly detection. While isotope identification is the time-honored method, an emerging technique is anomaly detection that uses benign vehicle gamma ray signatures to define an expectation of the radiation signature for vehicles that do not pose a threat. Newly acquired spectra are then compared to this expectation using statistical criteria that reflect acceptable false alarm rates and probabilities of detection. The gamma-ray spectra analyzed here were collected at a U.S. land Port of Entry (POE) using a NaI-based radiation portal monitor (RPM). The raw data were analyzed to develop a benign vehicle expectation by decimating the original pulse-height channels to 35 energy bins, extracting composite variables via principal components analysis (PCA), and estimating statistically weighted distances from the mean vehicle spectrum with the mahalanobis distance (MD) metric. This paper reviews the methods used to establish the anomaly identification criteria and presents a systematic analysis of the response of the combined PCA and MD algorithm to modeled mono-energetic gamma-ray sources

  1. Simultaneous measurement of aerodynamic and heat transfer data for large angle blunt cones in hypersonic shock tunnel

    Indian Academy of Sciences (India)

    Niranjan Sahoo; S Saravanan; G Jagadeesh; K P J Reddy

    2006-10-01

    Aerodynamic forces and fore-body convective surface heat transfer rates over a 60° apex-angle blunt cone have been simultaneously measured at a nominal Mach number of 5·75 in the hypersonic shock tunnel HST2. An aluminum model incorporating a three-component accelerometer-based balance system for measuring the aerodynamic forces and an array of platinum thin-film gauges deposited on thermally insulating backing material flush mounted on the model surface is used for convective surface heat transfer measurement in the investigations. The measured value of the drag coefficient varies by about $\\pm 6$% from the theoretically estimated value based on the modified Newtonian theory, while the axi-symmetric Navier–Stokes computations overpredict the drag coefficient by about 9%. The normalized values of measured heat transfer rates at 0° angle of attack are about 11% higher than the theoretically estimated values. The aerodynamic and the heat transfer data presented here are very valuable for the validation of CFD codes used for the numerical computation of flow fields around hypersonic vehicles.

  2. A Study of a Lifting Body as a Space Station Crew Exigency Return Vehicle (CERV)

    Science.gov (United States)

    MacConochie, Ian O.

    2000-01-01

    A lifting body is described for use as a return vehicle for crews from a space station. Reentry trajectories, subsystem weights and performance, and costs are included. The baseline vehicle is sized for a crew of eight. An alternate configuration is shown in which only four crew are carried with the extra volume reserved for logistics cargo. A water parachute recovery system is shown as an emergency alternative to a runway landing. Primary reaction control thrusters from the Shuttle program are used for orbital maneuvering while the Shuttle verniers are used for all attitude control maneuvers.

  3. Thermal Storage System for Electric Vehicle Cabin Heating Component and System Analysis

    Energy Technology Data Exchange (ETDEWEB)

    LaClair, Tim J [ORNL; Gao, Zhiming [ORNL; Abdelaziz, Omar [ORNL; Wang, Mingyu [MAHLE Behr Troy Inc.; WolfeIV, Edward [MAHLE Behr Troy Inc.; Craig, Timothy [MAHLE Behr Troy Inc.

    2016-01-01

    Cabin heating of current electric vehicle (EV) designs is typically provided using electrical energy from the traction battery, since waste heat is not available from an engine as in the case of a conventional automobile. In very cold climatic conditions, the power required for space heating of an EV can be of a similar magnitude to that required for propulsion of the vehicle. As a result, its driving range can be reduced very significantly during the winter season, which limits consumer acceptance of EVs and results in increased battery costs to achieve a minimum range while ensuring comfort to the EV driver. To minimize the range penalty associated with EV cabin heating, a novel climate control system that includes thermal energy storage from an advanced phase change material (PCM) has been designed for use in EVs and plug-in hybrid electric vehicles (PHEVs). The present paper focuses on the modeling and analysis of this electrical PCM-Assisted Thermal Heating System (ePATHS) and is a companion to the paper Design and Testing of a Thermal Storage System for Electric Vehicle Cabin Heating. A detailed heat transfer model was developed to simulate the PCM heat exchanger that is at the heart of the ePATHS and was subsequently used to analyze and optimize its design. The results from this analysis were integrated into a MATLAB Simulink system model to simulate the fluid flow, pressure drop and heat transfer in all components of the ePATHS. The system model was then used to predict the performance of the climate control system in the vehicle and to evaluate control strategies needed to achieve the desired temperature control in the cabin. The analysis performed to design the ePATHS is described in detail and the system s predicted performance in a vehicle HVAC system is presented.

  4. Vertical Corner Feature Based Precise Vehicle Localization Using 3D LIDAR in Urban Area.

    Science.gov (United States)

    Im, Jun-Hyuck; Im, Sung-Hyuck; Jee, Gyu-In

    2016-01-01

    Tall buildings are concentrated in urban areas. The outer walls of buildings are vertically erected to the ground and almost flat. Therefore, the vertical corners that meet the vertical planes are present everywhere in urban areas. These corners act as convenient landmarks, which can be extracted by using the light detection and ranging (LIDAR) sensor. A vertical corner feature based precise vehicle localization method is proposed in this paper and implemented using 3D LIDAR (Velodyne HDL-32E). The vehicle motion is predicted by accumulating the pose increment output from the iterative closest point (ICP) algorithm based on the geometric relations between the scan data of the 3D LIDAR. The vertical corner is extracted using the proposed corner extraction method. The vehicle position is then corrected by matching the prebuilt corner map with the extracted corner. The experiment was carried out in the Gangnam area of Seoul, South Korea. In the experimental results, the maximum horizontal position error is about 0.46 m and the 2D Root Mean Square (RMS) horizontal error is about 0.138 m. PMID:27517936

  5. Vertical Corner Feature Based Precise Vehicle Localization Using 3D LIDAR in Urban Area

    Directory of Open Access Journals (Sweden)

    Jun-Hyuck Im

    2016-08-01

    Full Text Available Tall buildings are concentrated in urban areas. The outer walls of buildings are vertically erected to the ground and almost flat. Therefore, the vertical corners that meet the vertical planes are present everywhere in urban areas. These corners act as convenient landmarks, which can be extracted by using the light detection and ranging (LIDAR sensor. A vertical corner feature based precise vehicle localization method is proposed in this paper and implemented using 3D LIDAR (Velodyne HDL-32E. The vehicle motion is predicted by accumulating the pose increment output from the iterative closest point (ICP algorithm based on the geometric relations between the scan data of the 3D LIDAR. The vertical corner is extracted using the proposed corner extraction method. The vehicle position is then corrected by matching the prebuilt corner map with the extracted corner. The experiment was carried out in the Gangnam area of Seoul, South Korea. In the experimental results, the maximum horizontal position error is about 0.46 m and the 2D Root Mean Square (RMS horizontal error is about 0.138 m.

  6. Attributed Relational Graph Based Feature Extraction of Body Poses In Indian Classical Dance Bharathanatyam

    OpenAIRE

    Athira. Sugathan; Suganya R.

    2014-01-01

    Articulated body pose estimation in computer vision is an important problem because of convolution of the models. It is useful in real time applications such as surveillance camera, computer games, human computer interaction etc. Feature extraction is the main part in pose estimation which helps for a successful classification. In this paper, we propose a system for extracting the features from the relational graph of articulated upper body poses of basic Bharatanatyam steps, ...

  7. A Pressure-distribution Investigation of the Aerodynamic Characteristics of a Body of Revolution in the Vicinity of a Reflection Plane at Mach Numbers of 1.41 and 2.01

    Science.gov (United States)

    Gapcynski, John P; Carlson, Harry W

    1955-01-01

    The changes in the aerodynamic characteristics of a body of revolution with a fineness ratio of 8 have been determined at Mach numbers of 1.41 and 2.01, a Reynolds number, based on body length, of 4.54 x 10 to the 6th power, and angles of incidence of 0 degrees and plus or minus 3 degrees as the position of the body is varied with respect to a reflection plane. The data are compared with theoretical results.

  8. Investigation of defect rate of lap laser welding of stainless steel railway vehicles car body

    Science.gov (United States)

    Wang, Hongxiao

    2015-02-01

    In order to resolve the disadvantages such as poor appearance quality, poor tightness, low efficiency of resistance spot welding of stainless steel rail vehicles, partial penetration lap laser welding process was investigated widely. But due to the limitation of processing technology, there will be local incomplete fusion in the lap laser welding seam. Defect rate is the ratio of the local incomplete fusion length to the weld seam length. The tensile shear strength under different defect rate and its effect on the car body static strength are not clear. It is necessary to find the biggest defect rate by numerical analysis of effects of different defect rates on the laser welding stainless steel rail vehicle body structure strength ,and tests of laser welding shear tensile strength.

  9. Comparison of Point and Line Features and Their Combination for Rigid Body Motion Estimation

    DEFF Research Database (Denmark)

    Pilz, Florian; Pugeault, Nicolas; Krüger, Norbert

    2009-01-01

    This paper discusses the usage of dierent image features and their combination in the context of estimating the motion of rigid bodies (RBM estimation). From stereo image sequences, we extract line features at local edges (coded in so called multi-modal primitives) as well as point features (by...... means of SIFT descriptors). All features are then matched across stereo and time, and we use these correspondences to estimate the RBM by solving the 3D-2D pose estimation problem. We test dierent feature sets on various stereo image sequences, recorded in realistic outdoor and indoor scenes. We...

  10. Multi-Functional Composite Design Concepts for Rail Vehicle Car Bodies

    OpenAIRE

    Wennberg, David

    2013-01-01

    Structures and material combinations, tailored for multiple purposes, are within the reach of vehicle manufacturers. Besides reducing the environmental impact of the transportation sector these multi-functional structures can reduce costs, such as development, manufacturing and maintenance, and at the same time offer improved comfort to the passengers. This thesis sets out to develop multi-functional design algorithms and evaluate concepts for future composite high speed train car bodies with...

  11. Human Factors Lessons Learned from Flight Testing Wingless Lifting Body Vehicles

    Science.gov (United States)

    Merlin, Peter William

    2014-01-01

    Since the 1960s, NASA, the Air Force, and now private industry have attempted to develop an operational human crewed reusable spacecraft with a wingless, lifting body configuration. This type of vehicle offers increased mission flexibility and greater reentry cross range than capsule type craft, and is particularly attractive due to the capability to land on a runway. That capability, however, adds complexity to the human factors engineering requirements of developing such aircraft.

  12. Pulsed Joining Of Body-In-White Components

    Energy Technology Data Exchange (ETDEWEB)

    Bonnen, John [Ford Motor Company, Dearborn, MI (United States)

    2014-09-30

    The objective of this project was to develop cost efficient high quality pulsed welding (PW) technology for joining 6xxx Aluminum and High Strength Steel (with tensile strength above 580MPa) components enabling broad usage of hydroformed parts and leading to substantial weight reduction of cars and trucks to reduce US demand on petroleum, lower carbon emissions and energy expenditures. In general, pulsed welding is a form of impact welding where two dissimilar metal pieces are joined by accelerating one to velocities exceeding 300m/s at which point the first piece strikes the second and forms a weld. In this work, two methods were used to accelerate the flyer material: Electro-Magnetic (EM) pulse and Electro-Hydraulic (EH) pulse launching. The advantage of pulsed welding techniques is that welds can be formed between two materials that cannot otherwise be welded: high strength aluminum and high strength steel. The technical objectives of the project included: 1) developing cost affordable production feasible tooling design for PW of 6xxx aluminum to High Strength steel with strengths above 580MPa; 2) demonstrating that fabricated joints can exceed the required service load strength initially at the coupon level and then at the component level; 3) developing fundamental understanding of the mechanisms of joint formation and conditions leading to formation of high quality PW joint; and 4) creating a numerical model predicting the tooling and electric discharge parameters necessary for the joint formation and that satisfy the targeted strength parameters. The project successfully developed: 1) EM and EH pulsed welds between high strength aluminum with tensile strengths exceeding 240MPa and steels exceeding 580MPa; 2) pulsed welds of extrusions with strengths exceeding project requirements; 3) EM and EH flyer launch models and 4) weld interface formation models. However, the grant holder, Ford Motor Company, could see no path to commercialization and the work was

  13. Robust multi-stream speech recognition based on weighting the output probabilities of feature components

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jun; WEI Gang; YU Hua; NING Genxin

    2009-01-01

    In the traditional multi-stream fusion methods of speech recognition, all the feature components in a data stream share the same stream weight, while their distortion levels are usually different when the speech recognizer works in noisy environments. To overcome this limitation of the traditional multi-stream frameworks, the current study proposes a new stream fusion method that weights not only the stream outputs, but also the output probabilities of feature components. How the stream and feature component weights in the new fusion method affect the decision is analyzed and two stream fusion schemes based on the 03iginalisation and soft decision models in the missing data techniques are proposed. Experimental results on the hybrid sub-band multi-stream speech recognizer show that the proposed schemes can adjust the stream influences on the decision adaptively and outperform the traditional multi-stream methods in various noisy environments.

  14. Flexible Launch Vehicle Stability Analysis Using Steady and Unsteady Computational Fluid Dynamics

    Science.gov (United States)

    Bartels, Robert E.

    2012-01-01

    Launch vehicles frequently experience a reduced stability margin through the transonic Mach number range. This reduced stability margin can be caused by the aerodynamic undamping one of the lower-frequency flexible or rigid body modes. Analysis of the behavior of a flexible vehicle is routinely performed with quasi-steady aerodynamic line loads derived from steady rigid aerodynamics. However, a quasi-steady aeroelastic stability analysis can be unconservative at the critical Mach numbers, where experiment or unsteady computational aeroelastic analysis show a reduced or even negative aerodynamic damping.Amethod of enhancing the quasi-steady aeroelastic stability analysis of a launch vehicle with unsteady aerodynamics is developed that uses unsteady computational fluid dynamics to compute the response of selected lower-frequency modes. The response is contained in a time history of the vehicle line loads. A proper orthogonal decomposition of the unsteady aerodynamic line-load response is used to reduce the scale of data volume and system identification is used to derive the aerodynamic stiffness, damping, and mass matrices. The results are compared with the damping and frequency computed from unsteady computational aeroelasticity and from a quasi-steady analysis. The results show that incorporating unsteady aerodynamics in this way brings the enhanced quasi-steady aeroelastic stability analysis into close agreement with the unsteady computational aeroelastic results.

  15. An Analysis on the Effects of Vehicle Anchoring on Aerodynamic Measurement in Wind Tunnel Test%风洞试验中车辆锚定方式对气动力测量的影响分析

    Institute of Scientific and Technical Information of China (English)

    陈力; 刘晓晖; 庞加斌; 杨志刚

    2014-01-01

    Aerodynamic force measurement of a vehicle with two different ways of anchoring is conducted in the first full scale aerodynamic / acoustic wind tunnel in China. The results indicate that with traditional floating mode, the rear end of vehicle rises at high wind speed, leading to a higher drag coefficient than that with fixed mode, and the maximum difference reaches 0. 006, while the lift coefficient with floating mode is smaller than that with fixed mode when wind speed is higher than 100 km/h with a maximum difference up to 0. 007 . So the effects of vehicle anchoring mode should be taken into consideration in aerodynamic measurement, and it is recommended to properly select the way of vehicle anchoring according to the objective and condition of test to ensure the accuracy of measurement.%利用国内首个整车气动声学风洞对某车辆在两种锚定方式下的气动力进行测量。结果表明,传统的浮动模式在高风速时车尾上翘,且上翘高度随着风速增加而增大。导致气动阻力系数比固定模式大,最大差值0.006。风速高于100km/h时气动升力系数比固定模式小,最大差值0.007。因此,整车气动力测量时应考虑锚定方式的影响,根据试验目的和条件合理选择车辆锚定方式,以保证测试精度。

  16. Unsteady aerodynamics modeling for flight dynamics application

    Science.gov (United States)

    Wang, Qing; He, Kai-Feng; Qian, Wei-Qi; Zhang, Tian-Jiao; Cheng, Yan-Qing; Wu, Kai-Yuan

    2012-02-01

    In view of engineering application, it is practicable to decompose the aerodynamics into three components: the static aerodynamics, the aerodynamic increment due to steady rotations, and the aerodynamic increment due to unsteady separated and vortical flow. The first and the second components can be presented in conventional forms, while the third is described using a one-order differential equation and a radial-basis-function (RBF) network. For an aircraft configuration, the mathematical models of 6-component aerodynamic coefficients are set up from the wind tunnel test data of pitch, yaw, roll, and coupled yawroll large-amplitude oscillations. The flight dynamics of an aircraft is studied by the bifurcation analysis technique in the case of quasi-steady aerodynamics and unsteady aerodynamics, respectively. The results show that: (1) unsteady aerodynamics has no effect upon the existence of trim points, but affects their stability; (2) unsteady aerodynamics has great effects upon the existence, stability, and amplitudes of periodic solutions; and (3) unsteady aerodynamics changes the stable regions of trim points obviously. Furthermore, the dynamic responses of the aircraft to elevator deflections are inspected. It is shown that the unsteady aerodynamics is beneficial to dynamic stability for the present aircraft. Finally, the effects of unsteady aerodynamics on the post-stall maneuverability are analyzed by numerical simulation.

  17. Unsteady aerodynamics modeling for flight dynamics application

    Institute of Scientific and Technical Information of China (English)

    Qing Wang; Kai-Feng He; Wei-Qi Qian; Tian-Jiao Zhang; Yan-Qing Cheng; Kai-Yuan Wu

    2012-01-01

    In view of engineering application,it is practicable to decompose the aerodynamics into three components:the static aerodynamics,the aerodynamic increment due to steady rotations,and the aerodynamic increment due to unsteady separated and vortical flow.The first and the second components can be presented in conventional forms,while the third is described using a one-order differential equation and a radial-basis-function (RBF) network. For an aircraft configuration,the mathematical models of 6-component aerodynamic coefficients are set up from the wind tunnel test data of pitch,yaw,roll,and coupled yawroll large-amplitude oscillations.The flight dynamics of an aircraft is studied by the bifurcation analysis technique in the case of quasi-steady aerodynamics and unsteady aerodynamics,respectively.The results show that:(1) unsteady aerodynamics has no effect upon the existence of trim points,but affects their stability; (2) unsteady aerodynamics has great effects upon the existence,stability,and amplitudes of periodic solutions; and (3) unsteady aerodynamics changes the stable regions of trim points obviously.Furthermore,the dynamic responses of the aircraft to elevator deflections are inspected.It is shown that the unsteady aerodynamics is beneficial to dynamic stability for the present aircraft.Finally,the effects of unsteady aerodynamics on the post-stall maneuverability are analyzed by numerical simulation.

  18. Life-Cycle Assessment of the Recycling of Magnesium Vehicle Components

    Science.gov (United States)

    Ehrenberger, Simone; Friedrich, Horst E.

    2013-10-01

    Life-cycle assessment is basically the assessment of a product from the cradle to the grave. Ideally, a product is recycled after its useful life is complete and the end-of-life of the first life cycle leads to the beginning of a new product system. For the end-of-life of magnesium vehicle parts, there are various possible paths to a second life cycle. When magnesium parts are dismantled or magnesium is separated after shredding, the resulting magnesium alloys can be used for secondary, noncritical applications. However, the typical case for magnesium components is that the magnesium postconsumer scrap ends up in the nonferrous metals fraction that consists primarily of aluminum, magnesium, and heavy metals. Today, aluminum is typically fed into a second life cycle as a secondary alloy, and magnesium becomes part of the aluminum cycle as an alloy addition. In this article, we evaluate the environmental effects of using magnesium in the aluminum cycle. We also assess the influence of end-of-life scenarios on the overall environmental impact of a component's life cycle. The primary focus of our analysis is the evaluation of the effects of magnesium vehicle components on greenhouse gas emissions.

  19. Scalable Components Modeling and Parallel Computing in Reentry Vehicle Electronic System

    Institute of Scientific and Technical Information of China (English)

    马卫东; 魏克辉

    2002-01-01

    In this paper, we discuss a kind of scalable modeling and simulation methods for Reentry Vehicle Electronic System (RVES) applied in our project and verification. We introduce the hierarchy for modeling and simulation of RVES firstly. The working scheme of R VES simulation system is based on the DEDS processed according to Finite Automation and the Continuous System Model adapted some electronic parts. Then we describe a kind of Component Modeling designed for Scalable capability and Plug and Play Software Bus. The design and implementation of Parallel Computing and Processing are discussed in the fourth part, which is very important for the software development in the scalable modeling and simulation system.

  20. Renal cell carcinoma with rhabdoid-like features lack intracytoplasmic inclusion bodies and show aggressive behavior.

    Science.gov (United States)

    Sugimoto, Masaaki; Kohashi, Kenichi; Kuroiwa, Kentaro; Abe, Tatsuro; Yamada, Yuichi; Shiota, Masaki; Imada, Kenjiro; Naito, Seiji; Oda, Yoshinao

    2016-03-01

    In renal cell carcinoma (RCC), tumor cells with rhabdoid features are characterized by eccentric nuclei, prominent nucleoli, and eosinophilic cytoplasm with intracytoplasmic inclusion bodies. In RCC, tumor cells have also been observed resembling rhabdomyoblasts or rhabdoid but without intracytoplasmic inclusion bodies, and here, we defined these rhabdoid-like features of these cells. To this end, we studied a series of clear cell RCC (ccRCC) with rhabdoid features and compared them with a series of ccRCC with rhabdoid-like features to clarify the differences in the immunohistochemical profile and biological behavior. From 695 cases of ccRCC (80.8 % of all RCCs), 18 cases with rhabdoid features (2.1 % of all RCCs) and 25 cases with rhabdoid-like features (2.9 % of all RCCs) were investigated. The 5-year survival rate for ccRCC with rhabdoid features was 44.7 % and for ccRCC with rhabdoid-like features 30.3 %. Although ccRCC with rhabdoid features showed immunohistochemical co-expression of epithelial markers and vimentin as seen in malignant rhabdoid tumors, ccRCC with rhabdoid-like features showed no such co-expression. Multivariate analyses of cancer-specific survival revealed that perinephric tissues invasion was an independent prognostic factor in ccRCC with rhabdoid features (p = 0.0253) but not in ccRCC with rhabdoid-like features. In summary, although their prognosis is similar, the marker profile and pattern of extension of ccRCC with rhabdoid-like is different from that of ccRCC with rhabdoid features. Therefore, ccRCC with rhabdoid-like features should be distinguished from ccRCC with rhabdoid features.

  1. 侧向风作用下车桥系统气动性能及风屏障的影响研究%Aerodynamic Characteristics of Vehicle-bridge System under Crosswinds and Effect of Wind Barriers

    Institute of Scientific and Technical Information of China (English)

    张田; 郭薇薇; 夏禾

    2013-01-01

    采用计算流体力学软件建立桥梁单体、车辆单体以及车桥组合体模型,湍流模型取标准κ-ε模型,计算各模型在不同风攻角时侧向风作用下的气动力系数.考虑风屏障对车辆、桥梁气动性能影响,建立风屏障、桥梁与车辆组合体模型,分析风屏障不同开孔率时车辆、桥梁气动力系数变化规律.结果表明:车辆位于桥上时,桥梁阻力和车辆侧力会增大;桥上车辆侧滚力矩系数明显大于车辆单独存在的情况,且车辆位于桥上迎风侧大于背风侧的情况;安装风屏障后,桥梁阻力和力矩系数随开孔率增大而降低,车辆侧力系数和力矩系数随开孔率增大而增大;为保证风屏障有效性,风屏障开孔率应小于40%.%On the basis of the CFD software platform and using the standard κ-ε turbulence model,numerical simulation was performed for the single bridge,single vehicle and vehicle-bridge combination under crosswinds.Their aerodynamic coefficients were calculated for different wind attack angles.The wind barrier-vehicle-bridge model was established in consideration of the effect of wind barriers on aerodynamic performance of the vehicle and bridge.The variation law of the aerodynamic coefficients of the vehicle and bridge with wind barriers of different porosity rates was analyzed.The results show as follows:When a vehicle is running on a bridge,the aerodynamic drag of the bridge and the side force coefficient of the vehicle are amplified; the rolling moment coefficient of the vehicle on the bridge is significantly greater than that of the vehicle alone,and the rolling moment coefficient of the vehicle on the bridge on the windward side is greater than that on the leeward side; the drag and rolling moment coefficient of the bridge with wind barriers decrease with increasing of the porosity percentage where as the above values of the vehicle increase with increasing of the porosity percentage; It is suggested that

  2. 无人机气动力地面车载测试系统%A ground test vehicle(GTV) system to measure the aerodynamic characteristics of unmanned air vehicles

    Institute of Scientific and Technical Information of China (English)

    贾毅; 张永升; 刘丹; 皮祖成; 郎卫东

    2013-01-01

    介绍了中国航天空气动力技术研究院开发的一种用于测量全尺寸无人机气动力的地面车载测试系统(GTV).车载测试系统采用一辆中型卡车进行相关改造,将试验无人机机身安装在其顶部,通过汽车牵引能够达到40km/h的速度.一套专用的测试天平系统和数据采集系统用于记录试验中无人机产生的升力、阻力以及俯仰力矩等数据.主要介绍测试天平系统的设计,数据采集测试系统,测试方法和试验结果.多元静态原位校准加载结果表明天平测试系统输出信号线性度以及重复性较好.动态校准试验采用一副定常展弦比6的机翼进行,试验结果与已知的风洞试验数据进行了比对.车载测试系统试验结果的升力和俯仰力矩数据不同车次之间重复性较好,并且与风洞试验数据基本一致.但阻力数据的离散度要比风洞试验时大得多,并且试验结果比风洞试验时偏小一些,试验证明地面车载测试系统的阻力测量难度较大.%A Ground Test Vehicle (GTV) system has been developed by China Academy of Aerospace Aerodynamics (CAAA) to provide a safe method for determining an experimental Unmanned Air Vehicle's (UAV) aerodynamic characteristics before flight.The GTV is a medium truck which has been modified to allow an UAV airframe to be mounted on top while propelling it up to 40km/h.A force balance and data acquisition system are used to measure and record the lift,drag and pitching moment of the test airframe.This paper describes the balance design,the data acquisition system,and the results of calibrations made to check the GTV data.A series of combined static loadings showed the force balance output to be linear and repeatable.A wing of constant chord aspect ratio 6 was tested,and the results were compared with available wind tunnel data.The lift and pitching moment data measured by the GTV for the test wing was repeatable for every run,and compared well with the

  3. Protein and lipid accretion in body components of growing pigs. Effects of body weight and nutrient intake.

    NARCIS (Netherlands)

    Bikker, P.

    1994-01-01

    In pig production, optimization of the conversion of animal feeding-stuffs into body components, especially lean meat, requires knowledge of the response relationships between nutrient intake and animal performance. In this study, the separate effects of protein and energy intake on rate and composi

  4. Robust Image Watermarking Using Local Invariant Features and Independent Component Analysis

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hanling; LIU Jie

    2006-01-01

    This paper proposes a novel robust image watermarking scheme for digital images using local invariant features and Independent Component Analysis(ICA). Most present watermarking algorithms are unable to resist geometric distortions that desynchronize the location. The method we propose here is robust to geometric attacks. In order to resist geometric distortions, we use a local invariant feature of the image called the scale invariant feature transform, which is invariant to translation and scaling distortions. The watermark is inserted into the circular patches generated by scale-invariant key point extractor. Rotation invariance is achieved using the translation property of the polar-mapped circular patches. Our method belongs to the blind watermark category, because we use Independent Component Analysis for detection that does not need the original image during detection. Experimental results show that our method is robust against geometric distortion attacks as well as signal-processing attacks.

  5. 49 CFR 238.419 - Truck-to-car-body and truck component attachment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Truck-to-car-body and truck component attachment. 238.419 Section 238.419 Transportation Other Regulations Relating to Transportation (Continued... attachment. (a) The ultimate strength of the truck-to-car-body attachment for each unit in a train shall...

  6. Proposal to use vibration analysis steering components and car body to monitor, for example, the state of unbalance wheel

    Science.gov (United States)

    Janczur, R.

    2016-09-01

    The results of road tests of car VW Passat equipped with tires of size 195/65 R15, on the influence of the unbalancing front wheel on vibration of the parts of steering system, steering wheel and the body of the vehicle have been presented in this paper. Unbalances wheels made using weights of different masses, placed close to the outer edge of the steel rim and checked on the machine Hunter GSP 9700 for balancing wheels. The recorded waveforms vibration steering components and car body, at different constant driving speeds, subjected to spectral analysis to determine the possibility of isolating vibration caused by unbalanced wheel in various states and coming from good quality asphalt road surface. The results were discussed in terms of the possibility of identifying the state of unbalancing wheels and possible changes in radial stiffness of the tire vibration transmitted through the system driving wheel on the steering wheel. Vibration analysis steering components and car body, also in the longitudinal direction, including information from the CAN bus of the state of motion of the car, can be used to monitor the development of the state of unbalance wheel, tire damage or errors shape of brake discs or brake drums, causing pulsations braking forces.

  7. A multi-body vehicle for moving inside cluttered nuclear environment

    International Nuclear Information System (INIS)

    The paper presents the result of the TALOS (Technologies for Advanced locomotion Systems) programme. The general aim of the TALOS was to prove the feasibility of multi-body articulated vehicles for intervention missions in nuclear plant were high payload volume and mass are required, combined with great geometrical and obstacles constraints. This programme was based on one hand on the TLV (Train Like Vehicle) concept, developed by CEA ( Atomic Energy Commission) and on the other hand on the KfK experience on locomotion. The main difficulties of this programme were to find the mechanical linkage concept and the locomotion concept, and also to build an integrated mockup with linkage and locomotion concepts. (TEC). 4 refs., 5 figs

  8. Analytical Approach for Estimating Preliminary Mass of ARES I Crew Launch Vehicle Upper Stage Structural Components

    Science.gov (United States)

    Aggarwal, Pravin

    2007-01-01

    electrical power functions to other Elements of the CLV, is included as secondary structure. The MSFC has an overall responsibility for the integrated US element as well as structural design an thermal control of the fuel tanks, intertank, interstage, avionics, main propulsion system, Reaction Control System (RCS) for both the Upper Stage and the First Stage. MSFC's Spacecraft and Vehicle Department, Structural and Analysis Design Division is developing a set of predicted mass of these elements. This paper details the methodology, criterion and tools used for the preliminary mass predictions of the upper stage structural assembly components. In general, weight of the cylindrical barrel sections are estimated using the commercial code Hypersizer, whereas, weight of the domes are developed using classical solutions. HyperSizer is software that performs automated structural analysis and sizing optimization based on aerospace methods for strength, stability, and stiffness. Analysis methods range from closed form, traditional hand calculations repeated every day in industry to more advanced panel buckling algorithms. Margin-of-safety reporting for every potential failure provides the engineer with a powerful insight into the structural problem. Optimization capabilities include finding minimum weight panel or beam concepts, material selections, cross sectional dimensions, thicknesses, and lay-ups from a library of 40 different stiffened and sandwich designs and a database of composite, metallic, honeycomb, and foam materials. Multiple different concepts (orthogrid, isogrid, and skin stiffener) were run for multiple loading combinations of ascent design load with and with out tank pressure as well as proof pressure condition. Subsequently, selected optimized concept obtained from Hypersizer runs was translated into a computer aid design (CAD) model to account for the wall thickness tolerance, weld land etc for developing the most probable weight of the components. The flow diram

  9. AIAA Applied Aerodynamics Conference, 10th, Palo Alto, CA, June 22-24, 1992, Technical Papers. Pts. 1 AND 2

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    Consideration is given to vortex physics and aerodynamics; supersonic/hypersonic aerodynamics; STOL/VSTOL/rotors; missile and reentry vehicle aerodynamics; CFD as applied to aircraft; unsteady aerodynamics; supersonic/hypersonic aerodynamics; low-speed/high-lift aerodynamics; airfoil/wing aerodynamics; measurement techniques; CFD-solvers/unstructured grid; airfoil/drag prediction; high angle-of-attack aerodynamics; and CFD grid methods. Particular attention is given to transonic-numerical investigation into high-angle-of-attack leading-edge vortex flow, prediction of rotor unsteady airloads using vortex filament theory, rapid synthesis for evaluating the missile maneuverability parameters, transonic calculations of wing/bodies with deflected control surfaces; the static and dynamic flow field development about a porous suction surface wing; the aircraft spoiler effects under wind shear; multipoint inverse design of an infinite cascade of airfoils, turbulence modeling for impinging jet flows; numerical investigation of tail buffet on the F-18 aircraft; the surface grid generation in a parameter space; and the flip flop nozzle extended to supersonic flows.

  10. Endogenous and exogenous components in the circadian variation of core body temperature in humans

    NARCIS (Netherlands)

    Hiddinga, AE; Beersma, DGM; VandenHoofdakker, RH

    1997-01-01

    Core body temperature is predominantly modulated by endogenous and exogenous components. In the present study we tested whether these two components can be reliably assessed in a protocol which lasts for only 120 h. In this so-called forced desynchrony protocol, 12 healthy male subjects (age 23.7 +/

  11. High fidelity replication of surface texture and geometric form of a high aspect ratio aerodynamic test component

    Science.gov (United States)

    Walton, Karl; Fleming, Leigh; Goodhand, Martin; Racasan, Radu; Zeng, Wenhan

    2016-06-01

    This paper details, assesses and validates a technique for the replication of a titanium wind tunnel test aerofoil in polyurethane resin. Existing resin replication techniques are adapted to overcome the technical difficulties associated with casting a high aspect ratio component. The technique is shown to have high replication fidelity over all important length-scales. The blade chord was accurate to 0.02%, and the maximum blade thickness was accurate to 2.5%. Important spatial and amplitude areal surface texture parameter were accurate to within 2%. Compared to an existing similar system using correlation areal parameters the current technique is shown to have lower fidelity and this difference is discussed. The current technique was developed for the measurement of boundary layer flow ‘laminar to turbulent’ transition for gas turbine compressor blade profiles and this application is illustrated.

  12. Accurate measurement of streamwise vortices in low speed aerodynamic flows

    Science.gov (United States)

    Waldman, Rye M.; Kudo, Jun; Breuer, Kenneth S.

    2010-11-01

    Low Reynolds number experiments with flapping animals (such as bats and small birds) are of current interest in understanding biological flight mechanics, and due to their application to Micro Air Vehicles (MAVs) which operate in a similar parameter space. Previous PIV wake measurements have described the structures left by bats and birds, and provided insight to the time history of their aerodynamic force generation; however, these studies have faced difficulty drawing quantitative conclusions due to significant experimental challenges associated with the highly three-dimensional and unsteady nature of the flows, and the low wake velocities associated with lifting bodies that only weigh a few grams. This requires the high-speed resolution of small flow features in a large field of view using limited laser energy and finite camera resolution. Cross-stream measurements are further complicated by the high out-of-plane flow which requires thick laser sheets and short interframe times. To quantify and address these challenges we present data from a model study on the wake behind a fixed wing at conditions comparable to those found in biological flight. We present a detailed analysis of the PIV wake measurements, discuss the criteria necessary for accurate measurements, and present a new dual-plane PIV configuration to resolve these issues.

  13. Negligible heat strain in armored vehicle officers wearing personal body armor

    Directory of Open Access Journals (Sweden)

    Hunt Andrew P

    2011-07-01

    Full Text Available Abstract Objectives This study evaluated the heat strain experienced by armored vehicle officers (AVOs wearing personal body armor (PBA in a sub-tropical climate. Methods Twelve male AVOs, aged 35-58 years, undertook an eight hour shift while wearing PBA. Heart rate and core temperature were monitored continuously. Urine specific gravity (USG was measured before and after, and with any urination during the shift. Results Heart rate indicated an intermittent and low-intensity nature of the work. USG revealed six AVOs were dehydrated from pre through post shift, and two others became dehydrated. Core temperature averaged 37.4 ± 0.3°C, with maximum's of 37.7 ± 0.2°C. Conclusions Despite increased age, body mass, and poor hydration practices, and Wet-Bulb Globe Temperatures in excess of 30°C; the intermittent nature and low intensity of the work prevented excessive heat strain from developing.

  14. Whole-body vibration in underground load-haul-dump vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Village, J.; Morrison, J.B.; Leong, D.K.N. (Simon Fraser University, Burnaby, BC (Canada). School of Kinesiology)

    1989-10-01

    A study was conducted to determine whole-body vibration (WBV) measurements at the seat plan of load-haul-dump (LHD) vehicles of 3-5, 5-, 6- and 8-yard capacity, at two underground mines. The vibration levels of heavy equipment have been reported to coincide with the most sensitive frequencies of the body and can have detrimental effects on vision, equilibrium, and manual dexterity. They can also be related to muscular fatigue, back injuries, and digestive and circulatory disorders. Data collected was compared with ISO standards; and an evaluation of the findings was conducted with respect to LHD accident and injury data, and information available in the literature on WBV. 26 refs., 8 figs., 4 tabs.

  15. An Interleaved Reduced-Component-Count Multivoltage Bus DC/DC Converter for Fuel Cell Powered Electric Vehicle Applications

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Lixin [ORNL; Su, Gui-Jia [ORNL

    2008-01-01

    An interleaved reduced-component-count dc/dc converter is proposed for power management in fuel cell powered vehicles with a multivoltage electric net. The converter is based on a simplified topology and can handle more power with less ripple current, therefore reducing the capacitor requirements, making it more suited for fuel cell powered vehicles in the near future. A prototype rated at 4.3 kW was built and tested to verify the proposed topology.

  16. 汽车气动噪声外辐射声场的数值仿真%Numerical Simulation on the External Radiation Sound Field of Vehicle Aerodynamic Noise

    Institute of Scientific and Technical Information of China (English)

    郑拯宇; 李人宪

    2013-01-01

    Based on Lighthill acoustic analogy theory and combining boundary element method ( BEM) with computational fluid dynamics ( CFD) , the pulsating pressure data of flow field boundary are input into the BEM model for a passenger car, and the boundary conditions of aerodynamic dipole sound source near car surface are obtained through conversion and calculation. A numerical simulation on the external radiation sound field of vehicle aerodynamic noise is conducted by using direct BEM. The results show that the intensity of dipole sound source on car surface decreases with the increase of frequency, the sound pressure level of aerodynamic noise near rearview mirrors is up to some 78 dB at 2,000Hz with a vehicle speed of 120km/h, and at the same frequency, the radiation intensity of aerodynamic sound source on the longitudinal symmetric plane of vehicle is larger than that on horizontal plane.%从Lighthill声类比理论出发,将流体动力学技术与边界元法结合起来,在某轿车边界元模型中,导入流场边界脉动压力数据,并经转换和计算获得汽车表面附近的气动偶极子声源边界条件;采用直接边界元算法进行汽车气动噪声外辐射声场的数值仿真.结果表明:轿车表面的偶极子声源强度随频率增大而降低;在120km/h车速和2000Hz频率时后视镜附近声场的气动噪声声压级可达78dB左右;在同一频率下,轿车在纵向对称面上的气动声源辐射强度要大于地平面上的气动声源辐射强度.

  17. Features of deformation of metal body surfaces under impact of a water jet

    Science.gov (United States)

    Aganin, A. A.; Khismatullina, N. A.

    2016-01-01

    The paper presents a mathematical model and computational results on dynamics of a perfect elastic-plastic body under the load arising during impact of a high-velocity liquid jet with the hemispherical end. The body is simulated by the isotropic linearly-elastic semi-space, its plastic state is described by the von Mises condition. The dependence of features of the body surface deformation on the body material is studied. The problem is considered in the axisymmetric statement. The axis of symmetry is that of the jet. The loaded domain is a circle with its radius rapidly growing from zero to the jet radius. The pressure in the loaded domain is non-uniform both in time and space. Three metal alloys (aluminium, copper-nickel and steel) are considered as the body material. The loading of the body surface in all the cases corresponds to the impact of a water jet with the radius 100 pm and the velocity 300 m/s. It has been shown that under such impact a nanometer pit arises on the body surface at the center of the domain of the jet action. The profile of the pit and its maximal depth depend on the body material.

  18. Optimal Feature Extraction Using Greedy Approach for Random Image Components and Subspace Approach in Face Recognition

    Institute of Scientific and Technical Information of China (English)

    Mathu Soothana S.Kumar Retna Swami; Muneeswaran Karuppiah

    2013-01-01

    An innovative and uniform framework based on a combination of Gabor wavelets with principal component analysis (PCA) and multiple discriminant analysis (MDA) is presented in this paper.In this framework,features are extracted from the optimal random image components using greedy approach.These feature vectors are then projected to subspaces for dimensionality reduction which is used for solving linear problems.The design of Gabor filters,PCA and MDA are crucial processes used for facial feature extraction.The FERET,ORL and YALE face databases are used to generate the results.Experiments show that optimal random image component selection (ORICS) plus MDA outperforms ORICS and subspace projection approach such as ORICS plus PCA.Our method achieves 96.25%,99.44% and 100% recognition accuracy on the FERET,ORL and YALE databases for 30% training respectively.This is a considerably improved performance compared with other standard methodologies described in the literature.

  19. Intelligent Autonomous Primary 3D Feature Extraction in Vehicle System Dynamics' Analysis: Theory and Application

    Directory of Open Access Journals (Sweden)

    Annamária R. Várkonyi-Kóczy

    2008-01-01

    Full Text Available 3D model reconstruction plays a very important role in computer vision as wellas in different engineering applications. The determination of the 3D model from multipleimages is of key importance. One of the most important difficulties in autonomous 3Dreconstruction is the (automatic selection of the ‘significant’ points which carryinformation about the shape of the 3D bodies i.e. are characteristic from the model point ofview. Another problem to be solved is the point correspondence matching in differentimages.In this paper a 3D reconstruction technique is introduced, which is capable to determinethe 3D model of a scene without any external (human intervention. The method is based onrecent results of image processing, epipolar geometry, and intelligent and soft techniques.Possible applications of the presented algorithm in vehicle system dynamics are alsopresented. The results can be applied advantageously at other engineering fields, like carcrashanalysis, robot guiding, object recognition, supervision of 3D scenes, etc,. as well.

  20. Investigation on used oil and engine components of vehicles road test using twenty percent Fatty Acid Methyl Ester (B20

    Directory of Open Access Journals (Sweden)

    Ihwan Haryono, Muhammad Ma’ruf, Hari Setiapraja

    2016-01-01

    Full Text Available The Indonesian government has mandated to utilize biodiesel at the Indonesian market with blend ratio of 20% biodiesel and 80% diesel fuel (B20. This policy bring car manufacturers concerning in using B20 effect on the engine life time. To evaluate the effect of using B20 on engine components, vehicles road test has been done along 40,000 KM. The test was using three brands of vehicles, in which each brand was composed of two identical vehicles fuelled by B20 FAME fuel and pure diesel fuel (B0 (solar. During the road test at certain intervals in accordance with the manufacturer's maintenance recommendations, the vehicles lubricating oil replacement and other routine maintenance were required. At the completion of the test all test vehicles to be dismantled and the engine components inspected. The test results show that the most parameter of used oil lubricants still in the limits. Likewise, the condition of the vehicles engine components did not show significant difference between using the pure diesel or B20.

  1. Dynamic Stability Analysis of Blunt Body Entry Vehicles Using Time-Lagged Aftbody Pitching Moments

    Science.gov (United States)

    Kazemba, Cole D.; Braun, Robert D.; Schoenenberger, Mark; Clark, Ian G.

    2013-01-01

    This analysis defines an analytic model for the pitching motion of blunt bodies during atmospheric entry. The proposed model is independent of the pitch damping sum coefficient present in the standard formulation of the equations of motion describing pitch oscillations of a decelerating blunt body, instead using the principle of a time-lagged aftbody moment as the forcing function for oscillation divergence. Four parameters, all with intuitive physical relevance, are introduced to fully define the aftbody moment and the associated time delay. It is shown that the dynamic oscillation responses typical to blunt bodies can be produced using hysteresis of the aftbody moment in place of the pitch damping coefficient. The approach used in this investigation is shown to be useful in understanding the governing physical mechanisms for blunt body dynamic stability and in guiding vehicle and mission design requirements. A validation case study using simulated ballistic range test data is conducted. From this, parameter identification is carried out through the use of a least squares optimizing routine. Results show good agreement with the limited existing literature for the parameters identified, suggesting that the model proposed could be validated by an experimental ballistic range test series. The trajectories produced by the identified parameters were found to match closely those from the MER ballistic range tests for a wide array of initial conditions and can be identified with a reasonable number of ballistic range shots and computational effort.

  2. NASP aerodynamics

    Science.gov (United States)

    Whitehead, Allen H., Jr.

    1989-01-01

    This paper discusses the critical aerodynamic technologies needed to support the development of a class of aircraft represented by the National Aero-Space Plane (NASP). The air-breathing, single-stage-to-orbit mission presents a severe challenge to all of the aeronautical disciplines and demands an extension of the state-of-the-art in each technology area. While the largest risk areas are probably advanced materials and the development of the scramjet engine, there remains a host of design issues and technology problems in aerodynamics, aerothermodynamics, and propulsion integration. The paper presents an overview of the most significant propulsion integration problems, and defines the most critical fluid flow phenomena that must be evaluated, defined, and predicted for the class of aircraft represented by the Aero-Space Plane.

  3. ATL_CMP: usSEABED component and features data for the entire U.S. Atlantic Coast

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This component data layer (_CMP.txt) file gives information about selected components (minerals, rock type, microfossils, benthic biota) and seafloor features...

  4. Evaluation of correction in shaping body mass women first adulthood with different personal features

    Directory of Open Access Journals (Sweden)

    Smaylova S.A.

    2013-06-01

    Full Text Available Assessed the effectiveness of training method of the "Shaping Classic" on the catabolic program correction of body weight the first mature age women with different personality characteristics. The study involved 20 women aged 26 - 30 years with a body mass index above average and high. Conducted anthropometric measurements. Used physiological tests, step test Prohorovtseva, engine test, psychodiagnostic methods. The efficiency of the program in reducing total body weight and body fat. The positive impact of the program on the functional state of the cardiovascular system and the musculoskeletal system is shown. Found that particular dispositions eating and self-esteem of women may reduce the level of impact of training. It is revealed that these features contribute to devaluing recommendations coach and weaken the motivation to train.

  5. Enhanced flyby science with onboard computer vision: Tracking and surface feature detection at small bodies

    Science.gov (United States)

    Fuchs, Thomas J.; Thompson, David R.; Bue, Brian D.; Castillo-Rogez, Julie; Chien, Steve A.; Gharibian, Dero; Wagstaff, Kiri L.

    2015-10-01

    Spacecraft autonomy is crucial to increase the science return of optical remote sensing observations at distant primitive bodies. To date, most small bodies exploration has involved short timescale flybys that execute prescripted data collection sequences. Light time delay means that the spacecraft must operate completely autonomously without direct control from the ground, but in most cases the physical properties and morphologies of prospective targets are unknown before the flyby. Surface features of interest are highly localized, and successful observations must account for geometry and illumination constraints. Under these circumstances onboard computer vision can improve science yield by responding immediately to collected imagery. It can reacquire bad data or identify features of opportunity for additional targeted measurements. We present a comprehensive framework for onboard computer vision for flyby missions at small bodies. We introduce novel algorithms for target tracking, target segmentation, surface feature detection, and anomaly detection. The performance and generalization power are evaluated in detail using expert annotations on data sets from previous encounters with primitive bodies.

  6. Human body parts tracking and kinematic features assessment based on RSSI and inertial sensor measurements.

    Science.gov (United States)

    Blumrosen, Gaddi; Luttwak, Ami

    2013-08-23

    Acquisition of patient kinematics in different environments plays an important role in the detection of risk situations such as fall detection in elderly patients, in rehabilitation of patients with injuries, and in the design of treatment plans for patients with neurological diseases. Received Signal Strength Indicator (RSSI) measurements in a Body Area Network (BAN), capture the signal power on a radio link. The main aim of this paper is to demonstrate the potential of utilizing RSSI measurements in assessment of human kinematic features, and to give methods to determine these features. RSSI measurements can be used for tracking different body parts' displacements on scales of a few centimeters, for classifying motion and gait patterns instead of inertial sensors, and to serve as an additional reference to other sensors, in particular inertial sensors. Criteria and analytical methods for body part tracking, kinematic motion feature extraction, and a Kalman filter model for aggregation of RSSI and inertial sensor were derived. The methods were verified by a set of experiments performed in an indoor environment. In the future, the use of RSSI measurements can help in continuous assessment of various kinematic features of patients during their daily life activities and enhance medical diagnosis accuracy with lower costs.

  7. Human Body Parts Tracking and Kinematic Features Assessment Based on RSSI and Inertial Sensor Measurements

    Directory of Open Access Journals (Sweden)

    Gaddi Blumrosen

    2013-08-01

    Full Text Available Acquisition of patient kinematics in different environments plays an important role in the detection of risk situations such as fall detection in elderly patients, in rehabilitation of patients with injuries, and in the design of treatment plans for patients with neurological diseases. Received Signal Strength Indicator (RSSI measurements in a Body Area Network (BAN, capture the signal power on a radio link. The main aim of this paper is to demonstrate the potential of utilizing RSSI measurements in assessment of human kinematic features, and to give methods to determine these features. RSSI measurements can be used for tracking different body parts’ displacements on scales of a few centimeters, for classifying motion and gait patterns instead of inertial sensors, and to serve as an additional reference to other sensors, in particular inertial sensors. Criteria and analytical methods for body part tracking, kinematic motion feature extraction, and a Kalman filter model for aggregation of RSSI and inertial sensor were derived. The methods were verified by a set of experiments performed in an indoor environment. In the future, the use of RSSI measurements can help in continuous assessment of various kinematic features of patients during their daily life activities and enhance medical diagnosis accuracy with lower costs.

  8. Systematic review of the toxicological and radiological features of body packing.

    Science.gov (United States)

    Cappelletti, Simone; Piacentino, Daria; Sani, Gabriele; Bottoni, Edoardo; Fiore, Paola Antonella; Aromatario, Mariarosaria; Ciallella, Costantino

    2016-05-01

    Body packing is the term used for the intracorporeal concealment of illicit drugs, mainly cocaine, heroin, methamphetamine, and cannabinoids. These drugs are produced in the form of packages and are swallowed or placed in various anatomical cavities and body orifices. Basing on these two ways of transportation a distinction between body stuffers and body pushers can be made, with the former described as drug users or street dealers who usually carry small amounts of drugs and the latter as professional drug couriers who carry greater amounts of drugs. A review of the literature regarding body packing is presented, with the aim to highlight the toxicological and radiological features related to this illegal practice. Raising awareness about the encountered mean body levels of the drugs and the typical imaging signs of the incorporated packages could be useful for clinicians and forensic pathologists to (a) identify possible unrecognized cases of body packing and (b) prevent the serious health consequences and deaths frequently occurring after the packages' leakage or rupture or the packages' mass obstructing the gastrointestinal lumen. PMID:26932867

  9. Structural components of the nuclear body in nuclei of Allium cepa cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Nuclear bodies have long been noted in interphase nuclei of plant cells,but their structural component,origin and function are still unclear by now.The present work showed in onion cells the nuclear bodies appeared as a spherical structure about 0.3 to 0.8 μm in diameter.They possibly were formed in nucleolus and subsequently released,and entered into nucleoplasm.Observation through cytochemical staining method at the ultrastructural level confirmed that nuclear bodies consisted of ribonucleoproteins (RNPs) and silver-stainable proteins.Immunocytochemical results revealed that nuclear bodies contained no DNA and ribosomal gene transcription factor (UBF).Based on these data,we suggested that nuclear bodies are not related to the ribosome or other gene transcription activities,instead they may act as subnuclear structures for RNPs transport from nucleolus to cytoplasm,and may also be involved in splicing of pre-mRNAs.

  10. Feasibility study for a numerical aerodynamic simulation facility. Volume 2: Hardware specifications/descriptions

    Science.gov (United States)

    Green, F. M.; Resnick, D. R.

    1979-01-01

    An FMP (Flow Model Processor) was designed for use in the Numerical Aerodynamic Simulation Facility (NASF). The NASF was developed to simulate fluid flow over three-dimensional bodies in wind tunnel environments and in free space. The facility is applicable to studying aerodynamic and aircraft body designs. The following general topics are discussed in this volume: (1) FMP functional computer specifications; (2) FMP instruction specification; (3) standard product system components; (4) loosely coupled network (LCN) specifications/description; and (5) three appendices: performance of trunk allocation contention elimination (trace) method, LCN channel protocol and proposed LCN unified second level protocol.

  11. Damage prognosis of adhesively-bonded joints in laminated composite structural components of unmanned aerial vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Farrar, Charles R [Los Alamos National Laboratory; Gobbato, Maurizio [UCSD; Conte, Joel [UCSD; Kosmatke, John [UCSD; Oliver, Joseph A [UCSD

    2009-01-01

    The extensive use of lightweight advanced composite materials in unmanned aerial vehicles (UAVs) drastically increases the sensitivity to both fatigue- and impact-induced damage of their critical structural components (e.g., wings and tail stabilizers) during service life. The spar-to-skin adhesive joints are considered one of the most fatigue sensitive subcomponents of a lightweight UAV composite wing with damage progressively evolving from the wing root. This paper presents a comprehensive probabilistic methodology for predicting the remaining service life of adhesively-bonded joints in laminated composite structural components of UAVs. Non-destructive evaluation techniques and Bayesian inference are used to (i) assess the current state of damage of the system and, (ii) update the probability distribution of the damage extent at various locations. A probabilistic model for future loads and a mechanics-based damage model are then used to stochastically propagate damage through the joint. Combined local (e.g., exceedance of a critical damage size) and global (e.g.. flutter instability) failure criteria are finally used to compute the probability of component failure at future times. The applicability and the partial validation of the proposed methodology are then briefly discussed by analyzing the debonding propagation, along a pre-defined adhesive interface, in a simply supported laminated composite beam with solid rectangular cross section, subjected to a concentrated load applied at mid-span. A specially developed Eliler-Bernoulli beam finite element with interlaminar slip along the damageable interface is used in combination with a cohesive zone model to study the fatigue-induced degradation in the adhesive material. The preliminary numerical results presented are promising for the future validation of the methodology.

  12. Drosophila SMN complex proteins Gemin2, Gemin3, and Gemin5 are components of U bodies

    Energy Technology Data Exchange (ETDEWEB)

    Cauchi, Ruben J.; Sanchez-Pulido, Luis [MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX (United Kingdom); Liu, Ji-Long, E-mail: jilong.liu@dpag.ox.ac.uk [MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX (United Kingdom)

    2010-08-15

    Uridine-rich small nuclear ribonucleoproteins (U snRNPs) play key roles in pre-mRNA processing in the nucleus. The assembly of most U snRNPs takes place in the cytoplasm and is facilitated by the survival motor neuron (SMN) complex. Discrete cytoplasmic RNA granules called U bodies have been proposed to be specific sites for snRNP assembly because they contain U snRNPs and SMN. U bodies invariably associate with P bodies, which are involved in mRNA decay and translational control. However, it remains unknown whether other SMN complex proteins also localise to U bodies. In Drosophila there are four SMN complex proteins, namely SMN, Gemin2/CG10419, Gemin3 and Gemin5/Rigor mortis. Drosophila Gemin3 was originally identified as the Drosophila orthologue of human and yeast Dhh1, a component of P bodies. Through an in silico analysis of the DEAD-box RNA helicases we confirmed that Gemin3 is the bona fide Drosophila orthologue of vertebrate Gemin3 whereas the Drosophila orthologue of Dhh1 is Me31B. We then made use of the Drosophila egg chamber as a model system to study the subcellular distribution of the Gemin proteins as well as Me31B. Our cytological investigations show that Gemin2, Gemin3 and Gemin5 colocalise with SMN in U bodies. Although they are excluded from P bodies, as components of U bodies, Gemin2, Gemin3 and Gemin5 are consistently found associated with P bodies, wherein Me31B resides. In addition to a role in snRNP biogenesis, SMN complexes residing in U bodies may also be involved in mRNP assembly and/or transport.

  13. Analysis and Test Correlation of Proof of Concept Box for Blended Wing Body-Low Speed Vehicle

    Science.gov (United States)

    Spellman, Regina L.

    2003-01-01

    The Low Speed Vehicle (LSV) is a 14.2% scale remotely piloted vehicle of the revolutionary Blended Wing Body concept. The design of the LSV includes an all composite airframe. Due to internal manufacturing capability restrictions, room temperature layups were necessary. An extensive materials testing and manufacturing process development effort was underwent to establish a process that would achieve the high modulus/low weight properties required to meet the design requirements. The analysis process involved a loads development effort that incorporated aero loads to determine internal forces that could be applied to a traditional FEM of the vehicle and to conduct detailed component analyses. A new tool, Hypersizer, was added to the design process to address various composite failure modes and to optimize the skin panel thickness of the upper and lower skins for the vehicle. The analysis required an iterative approach as material properties were continually changing. As a part of the material characterization effort, test articles, including a proof of concept wing box and a full-scale wing, were fabricated. The proof of concept box was fabricated based on very preliminary material studies and tested in bending, torsion, and shear. The box was then tested to failure under shear. The proof of concept box was also analyzed using Nastran and Hypersizer. The results of both analyses were scaled to determine the predicted failure load. The test results were compared to both the Nastran and Hypersizer analytical predictions. The actual failure occurred at 899 lbs. The failure was predicted at 1167 lbs based on the Nastran analysis. The Hypersizer analysis predicted a lower failure load of 960 lbs. The Nastran analysis alone was not sufficient to predict the failure load because it does not identify local composite failure modes. This analysis has traditionally been done using closed form solutions. Although Hypersizer is typically used as an optimizer for the design

  14. Saltation-threshold model can explain aeolian features on low-air-density planetary bodies

    CERN Document Server

    Pähtz, Thomas

    2016-01-01

    Knowledge of the minimal fluid speeds at which sediment transport can be sustained is crucial for understanding whether underwater landscapes exposed to water streams and wind-blown loose planetary surfaces can be altered. It also tells us whether surface features, such as ripples and dunes, can evolve. Here, guided by state-of-the-art numerical simulations, we propose an analytical model predicting the minimal fluid speeds required to sustain sediment transport in a Newtonian fluid. The model results are consistent with measurements and estimates of the transport threshold in water and Earth's and Mars' atmospheres. Furthermore, it predicts reasonable wind speeds to sustain aeolian sediment transport ("saltation") on the low-air-density planetary bodies Triton, Pluto, and 67P/Churyumov-Gerasimenko (comet). This offers an explanation for possible aeolian surface features photographed on these bodies during space missions.

  15. Aerodynamic configuration design of a buoyancy-lifting vehicle in the near-space%一种临近空间升浮一体飞行器气动布局设计研究

    Institute of Scientific and Technical Information of China (English)

    陈广强; 刘强; 石永彬; 白鹏; 纪楚群

    2015-01-01

    应用理论方法和数值模拟方法开展升浮一体太阳能无人机气动布局设计研究,通过优化选形设计获得高升阻比气动布局,对比两种方法的计算结果以及分析存在差别的原因;应用张线天平支撑风洞试验测试技术,对设计布局开展实验验证研究,建立大展弦比的双机身气动布局风洞试验测试方法,分析了不同雷诺数下实验模型的纵向和横向气动特性影响。研究结果表明:风洞试验结果与设计结果吻合良好,验证了设计结果的可靠性,获得了对总体设计具有指导意义的结论和试验数据结果。%The aerodynamic configurations of a solar powered buoyancy—lifting vehicle in the near—space were investigated using both engineering method and Computational fluid dynamics. The optimized aerodynamic configurations with high lift to drag ratio were obtained by optimiza—tion design method respectively,and the differences between two cofigurations from the two methods were analyzed.Experiment study on the aerodynamics configuration was done by cable mounting wind tunnel testing technology,and testing methods in wind tune experiment of high aspect ratio with two fuselages configuration were developed.Aerodynamic performance of the test model in pitching and lateral were analyzed in different Reynolds number.Conclusion of this investigation showed that wind tunnel experiment results and computational results were according well one another and the configuration design methods were validated,experiment results could give technology support to solar powered buoyancy—lifting vehicle system overall design as well.

  16. Lamb wave feature extraction using discrete wavelet transformation and Principal Component Analysis

    Science.gov (United States)

    Ghodsi, Mojtaba; Ziaiefar, Hamidreza; Amiryan, Milad; Honarvar, Farhang; Hojjat, Yousef; Mahmoudi, Mehdi; Al-Yahmadi, Amur; Bahadur, Issam

    2016-04-01

    In this research, a new method is presented for eliciting the proper features for recognizing and classifying the kinds of the defects by guided ultrasonic waves. After applying suitable preprocessing, the suggested method extracts the base frequency band from the received signals by discrete wavelet transform and discrete Fourier transform. This frequency band can be used as a distinctive feature of ultrasonic signals in different defects. Principal Component Analysis with improving this feature and decreasing extra data managed to improve classification. In this study, ultrasonic test with A0 mode lamb wave is used and is appropriated to reduce the difficulties around the problem. The defects under analysis included corrosion, crack and local thickness reduction. The last defect is caused by electro discharge machining (EDM). The results of the classification by optimized Neural Network depicts that the presented method can differentiate different defects with 95% precision and thus, it is a strong and efficient method. Moreover, comparing the elicited features for corrosion and local thickness reduction and also the results of the two's classification clarifies that modeling the corrosion procedure by local thickness reduction which was previously common, is not an appropriate method and the signals received from the two defects are different from each other.

  17. Learning representative features for facial images based on a modified principal component analysis

    Science.gov (United States)

    Averkin, Anton; Potapov, Alexey

    2013-05-01

    The paper is devoted to facial image analysis and particularly deals with the problem of automatic evaluation of the attractiveness of human faces. We propose a new approach for automatic construction of feature space based on a modified principal component analysis. Input data sets for the algorithm are the learning data sets of facial images, which are rated by one person. The proposed approach allows one to extract features of the individual subjective face beauty perception and to predict attractiveness values for new facial images, which were not included into a learning data set. The Pearson correlation coefficient between values predicted by our method for new facial images and personal attractiveness estimation values equals to 0.89. This means that the new approach proposed is promising and can be used for predicting subjective face attractiveness values in real systems of the facial images analysis.

  18. Multi-center MRI carotid plaque component segmentation using feature normalization and transfer learning

    DEFF Research Database (Denmark)

    van Engelen, Arna; van Dijk, Anouk C; Truijman, Martine T.B.;

    2015-01-01

    weights. Results showed that the best results were obtained for a combination of feature normalization and transfer learning. While for the other approaches significant differences in voxelwise or mean volume errors were found compared with the reference samecenter training, the proposed approach did...... not yield significant differences from that reference. We conclude that both extensive feature normalization and transfer learning can be valuable for the development of supervised methods that perform well on different types of datasets.......Automated segmentation of plaque components in carotid artery MRI is important to enable large studies on plaque vulnerability, and for incorporating plaque composition as an imaging biomarker in clinical practice. Especially supervised classification techniques, which learn from labeled examples...

  19. Ride comfort characteristics with different tire pressure of passenger vehicle featuring MR damper

    International Nuclear Information System (INIS)

    This paper presents ride comfort characteristics of a quarter-vehicle magneto-rheological (MR) suspension system with respect to different tire pressure. As a first step, controllable MR damper is designed and manufactured based on the optimized damping force levels and mechanical dimensions required for a commercial mid-sized passenger vehicle. After experimentally evaluating dynamic characteristics of the manufactured MR damper, the quarter-vehicle suspension system consisting of sprung mass, spring, tire and the MR damper is constructed in order to investigate the ride comfort. After deriving the equations of the motion for the proposed quarter-vehicle MR suspension system, vertical tire stiffness with respect to different tire pressure is experimentally identified. The skyhook controller is then implemented for the realization of quarter-vehicle MR suspension system. Ride comfort characteristics such as vertical acceleration RMS of sprung mass are evaluated under bump road condition and presented in time domain.

  20. Polarized spectral features of human breast tissues through wavelet transform and principal component analysis

    Indian Academy of Sciences (India)

    Anita Gharekhan; Ashok N Oza; M B Sureshkumar; Asima Pradhan; Prasanta K Panigrahi

    2010-12-01

    Fluorescence characteristics of human breast tissues are investigated through wavelet transform and principal component analysis (PCA). Wavelet transform of polarized fluorescence spectra of human breast tissues is found to localize spectral features that can reliably differentiate different tissue types. The emission range in the visible wavelength regime of 500–700 nm is analysed, with the excitation wavelength at 488 nm using laser as an excitation source, where flavin and porphyrin are some of the active fluorophores. A number of global and local parameters from principal component analysis of both high- and low-pass coefficients extracted in the wavelet domain, capturing spectral variations and subtle changes in the diseased tissues are clearly identifiable.

  1. Instabilities on crystal surfaces: The two-component body-centered solid-on-solid model

    NARCIS (Netherlands)

    Carlon, E.; van Beijeren, H.; Mazzeo, G.

    1996-01-01

    The free energy of crystal surfaces that can be described by the two-component body-centered solid-on-solid model has been calculated in a mean-field approximation. The system may model ionic crystals with a bcc lattice structure (for instance CsCl). Crossings between steps are energetically favored

  2. Research and services for vehicle bodies; Forschung und Dienstleistung fuer die Karosserie

    Energy Technology Data Exchange (ETDEWEB)

    Grandel, J.; Mueller, C.F.

    1998-09-01

    The KTI institute for automotive engineering and vehicle bodies is a research institute sponsored by the Dekra group, the insurance sector and the automotive trade. Basic research and practical repair work carried out in the institute`s own workshops with their integrated paint-shops form the basis for providing competent support for developments in the field of repair-friendly vehicle design, repair methods and loss adjustment. With its repair crash tests, time studies and training courses, the KTI contributes to reducing accident and repair costs. The technical documentation department supplies repair manuals and training literature. (orig.) [Deutsch] Das KTI - Kraftfahrzeugtechnisches Institut und Karosseriewerkstaette - ist ein Forschungsinstitut der DEKRA-Gruppe, der Versicherungswirtschaft und des Kfz-Handwerks. Grundlagenforschung und Reparaturpraxis in der eigenen Reparaturwerkstaette mit integrierter Lackieranlage bilden ideale Voraussetzungen zur kompetenten Begleitung von Entwicklungen im Bereich der reparaturfreundlichen Fahrzeugkonstruktion, der Reparaturverfahren und der Schadensabwicklung. Mit Reparaturcrashversuchen, Zeitstudien und Lehrgaengen traegt das KTI zur Reduzierung von Unfall- und Reparaturkosten bei. Die Technische Dokumentation liefert Reparaturhandbuecher und Trainigsliteratur. (orig.)

  3. Improvement Solutions and Methodology of UAV Micro-class Aerodynamic Characteristics

    OpenAIRE

    Urbahs, A; Petrovs, V; Urbaha, M; Carjova, K

    2014-01-01

    The paper contains the analysis of basic features characterizing the development and modernization of micro-class unmanned aerial vehicle (UAV) performance characteristics. The UAV is mainly used for environmental monitoring and for the monitoring of different industrial facilities. The study offers the ways of modernizing the UAV embodiment. It considers the methodology for improving UAV aerodynamic and structural characteristics by using modern calculation methods. The study also includes a...

  4. Aerodynamics of magnetic levitation (MAGLEV) trains

    Science.gov (United States)

    Schetz, Joseph A.; Marchman, James F., III

    1996-01-01

    High-speed (500 kph) trains using magnetic forces for levitation, propulsion and control offer many advantages for the nation and a good opportunity for the aerospace community to apply 'high tech' methods to the domestic sector. One area of many that will need advanced research is the aerodynamics of such MAGLEV (Magnetic Levitation) vehicles. There are important issues with regard to wind tunnel testing and the application of CFD to these devices. This talk will deal with the aerodynamic design of MAGLEV vehicles with emphasis on wind tunnel testing. The moving track facility designed and constructed in the 6 ft. Stability Wind Tunnel at Virginia Tech will be described. Test results for a variety of MAGLEV vehicle configurations will be presented. The last topic to be discussed is a Multi-disciplinary Design approach that is being applied to MAGLEV vehicle configuration design including aerodynamics, structures, manufacturability and life-cycle cost.

  5. Natural aerodynamics

    CERN Document Server

    Scorer, R S

    1958-01-01

    Natural Aerodynamics focuses on the mathematics of any problem in air motion.This book discusses the general form of the law of fluid motion, relationship between pressure and wind, production of vortex filaments, and conduction of vorticity by viscosity. The flow at moderate Reynolds numbers, turbulence in a stably stratified fluid, natural exploitation of atmospheric thermals, and plumes in turbulent crosswinds are also elaborated. This text likewise considers the waves produced by thermals, transformation of thin layer clouds, method of small perturbations, and dangers of extra-polation.Thi

  6. Growth and deposition of body components of intermediate and high performance broilers

    Directory of Open Access Journals (Sweden)

    JD Henn

    2014-09-01

    Full Text Available The objectives of the present study were to determine the parameters of Gompertz equations and to determine curves and growth rate, feed intake and body component deposition, as well as allometric coefficients of body water, protein, and fat relative to live weight of male and female broilers of intermediate performance (C44 and high performance (Cobb-500 genetic strains. In total, 384 one-d-old chicks were distributed into four treatments: male Cobb 500, male C44, female Cobb 500, and female C44, with six replicates of 16 birds, according to a completely randomized experimental design. Average body weight, weight gain, and feed intake were weekly determined, and six birds, representing the average weight of each treatment, were sacrificed to determine body composition. Growth curves were built applying Gompertz function, with excellent fit, and growth, feed intake, and tissue deposition rates were obtained by its derivatives. Superior growth rate was obtained for Cobb 500 male broilers. This genetic strain has higher feed intake capacity, which is achieved earlier than in the C44 strain. Protein and fat deposition maturity was reached earlier in males than in females in Cobb 500. The allometric coefficients showed earlier maturity for body water in C44 and females. In terms of body protein, male Cobb 500 broilers reached maturity earlier than females and C44. Body fat deposition maturity was reached earlier in Cobb 500 than in C44. The Gompertz equations obtained in the present study efficiently described body growth, feed intake, and deposition of body components, with a coefficient of determination higher than 0.99.

  7. Combustor and Vane Features and Components Tested in a Gas Turbine Environment

    Science.gov (United States)

    Roinson, R. Craig; Verrilli, Michael J.

    2003-01-01

    The use of ceramic matrix composites (CMCs) as combustor liners and turbine vanes provides the potential of improving next-generation turbine engine performance, through lower emissions and higher cycle efficiency, relative to today s use of superalloy hot-section components. For example, the introduction of film-cooling air in metal combustor liners has led to higher levels of nitrogen oxide (NOx) emissions from the combustion process. An environmental barrier coated (EBC) siliconcarbide- fiber-reinforced silicon carbide matrix (SiC/SiC) composite is a new material system that can operate at higher temperatures, significantly reducing the film-cooling requirements and enabling lower NOx production. Evaluating components and subcomponents fabricated from these advanced CMCs under gas turbine conditions is paramount to demonstrating that the material system can perform as required in the complex thermal stress and environmentally aggressive engine environment. To date, only limited testing has been conducted on CMC combustor and turbine concepts and subelements of this type throughout the industry. As part of the Ultra-Efficient Engine Technology (UEET) Program, the High Pressure Burner Rig (HPBR) at the NASA Glenn Research Center was selected to demonstrate coupon, subcomponent feature, and component testing because it can economically provide the temperatures, pressures, velocities, and combustion gas compositions that closely simulate the engine environments. The results have proven the HPBR to be a highly versatile test rig amenable to multiple test specimen configurations essential to coupon and component testing.

  8. Attributed Relational Graph Based Feature Extraction of Body Poses In Indian Classical Dance Bharathanatyam

    Directory of Open Access Journals (Sweden)

    Athira. Sugathan

    2014-05-01

    Full Text Available Articulated body pose estimation in computer vision is an important problem because of convolution of the models. It is useful in real time applications such as surveillance camera, computer games, human computer interaction etc. Feature extraction is the main part in pose estimation which helps for a successful classification. In this paper, we propose a system for extracting the features from the relational graph of articulated upper body poses of basic Bharatanatyam steps, each performed by different persons of different experiences and size. Our method has the ability to extract features from an attributed relational graph from challenging images with background clutters, clothing diversity, illumination etc. The system starts with skeletonization process which determines the human pose and increases the smoothness using B-Spline approach. Attributed relational graph is generated and the geometrical features are extracted for the correct discrimination between shapes that can be useful for classification and annotation of dance poses. We evaluate our approach experimentally on 2D images of basic Bharatanatyam poses.

  9. Modelling of Components for Conventional Car and Hybrid Electric Vehicle in Modelica

    OpenAIRE

    Wallén, Johanna

    2004-01-01

    Hybrid electric vehicles have two power sources - an internal combustion engine and an electric motor. These vehicles are of great interest because they contribute to a decreasing fuel consumption and air pollution and still maintain the performance of a conventional car. Different topologies are described in this thesis and especially the series and parallel hybrid electric vehicle and Toyota Prius have been studied. This thesis also depicts modelling of a reference car and a series hybrid ...

  10. The clinical features of foreign body aspiration into the lower airway in geriatric patients

    Directory of Open Access Journals (Sweden)

    Lin LJ

    2014-09-01

    Full Text Available Lianjun Lin,1 Liping Lv,2,* Yuchuan Wang,1 Xiankui Zha,2 Fei Tang,2 Xinmin Liu1,* 1Geriatric Department, Peking University First Hospital, Beijing, People’s Republic of China; 2Pulmonary Intervention Department, Anhui Chest Hospital, Hefei, People’s Republic of China *These authors contributed equally to this work Purpose: To analyze the clinical features of foreign-body aspiration into the lower airway in geriatric patients. Patients and methods: The clinical data of 17 geriatric patients with foreign-body aspiration were retrospectively analyzed and compared with 26 nongeriatric adult patients. The data were collected from Peking University First Hospital and Anhui Chest Hospital between January 2000 and June 2014.Results: (1 In the geriatric group, the most common symptoms were cough and sputum (15 cases, 88%, dyspnea (six cases, 35%, and hemoptysis (four cases, 24%. Five patients (29% in the geriatric group could supply the history of aspiration on their first visit to doctor, a smaller percentage than in the nongeriatric group (13 cases, 50%. Only three cases in the geriatric group were diagnosed definitely without delay. Another 14 cases were misdiagnosed as pneumonia or lung cancer, and the time of delayed diagnosis ranged from 1 month to 3 years. Complications due to delay in diagnosis included obstructive pneumonitis, atelectasis, lung abscess, and pleural effusion. (2 Chest computed tomography demonstrated the foreign body in three cases (21% in the geriatric group, which was lower than the positive proportion of detection in the nongeriatric group (nine cases, 35%. The most common type of foreign body in the geriatric group was food, such as bone fragments (seven cases, 41% and plants (seven cases, 41%, and the foreign body was most often lodged in the right bronchus tree (eleven cases, 65%, especially the right lower bronchus (seven cases, 41%. Flexible bronchoscopy removed the foreign body successfully in all patients

  11. Internal air flow analysis of a bladeless micro aerial vehicle hemisphere body using computational fluid dynamic

    Energy Technology Data Exchange (ETDEWEB)

    Othman, M. N. K., E-mail: najibkhir86@gmail.com, E-mail: zuradzman@unimap.edu.my, E-mail: hazry@unimap.edu.my, E-mail: khairunizam@unimap.edu.my, E-mail: shahriman@unimap.edu.my, E-mail: s.yaacob@unimap.edu.my, E-mail: syedfaiz@unimap.edu.my, E-mail: abadal@unimap.edu.my; Zuradzman, M. Razlan, E-mail: najibkhir86@gmail.com, E-mail: zuradzman@unimap.edu.my, E-mail: hazry@unimap.edu.my, E-mail: khairunizam@unimap.edu.my, E-mail: shahriman@unimap.edu.my, E-mail: s.yaacob@unimap.edu.my, E-mail: syedfaiz@unimap.edu.my, E-mail: abadal@unimap.edu.my; Hazry, D., E-mail: najibkhir86@gmail.com, E-mail: zuradzman@unimap.edu.my, E-mail: hazry@unimap.edu.my, E-mail: khairunizam@unimap.edu.my, E-mail: shahriman@unimap.edu.my, E-mail: s.yaacob@unimap.edu.my, E-mail: syedfaiz@unimap.edu.my, E-mail: abadal@unimap.edu.my; Khairunizam, Wan, E-mail: najibkhir86@gmail.com, E-mail: zuradzman@unimap.edu.my, E-mail: hazry@unimap.edu.my, E-mail: khairunizam@unimap.edu.my, E-mail: shahriman@unimap.edu.my, E-mail: s.yaacob@unimap.edu.my, E-mail: syedfaiz@unimap.edu.my, E-mail: abadal@unimap.edu.my; Shahriman, A. B., E-mail: najibkhir86@gmail.com, E-mail: zuradzman@unimap.edu.my, E-mail: hazry@unimap.edu.my, E-mail: khairunizam@unimap.edu.my, E-mail: shahriman@unimap.edu.my, E-mail: s.yaacob@unimap.edu.my, E-mail: syedfaiz@unimap.edu.my, E-mail: abadal@unimap.edu.my; Yaacob, S., E-mail: najibkhir86@gmail.com, E-mail: zuradzman@unimap.edu.my, E-mail: hazry@unimap.edu.my, E-mail: khairunizam@unimap.edu.my, E-mail: shahriman@unimap.edu.my, E-mail: s.yaacob@unimap.edu.my, E-mail: syedfaiz@unimap.edu.my, E-mail: abadal@unimap.edu.my; Ahmed, S. Faiz, E-mail: najibkhir86@gmail.com, E-mail: zuradzman@unimap.edu.my, E-mail: hazry@unimap.edu.my, E-mail: khairunizam@unimap.edu.my, E-mail: shahriman@unimap.edu.my, E-mail: s.yaacob@unimap.edu.my, E-mail: syedfaiz@unimap.edu.my, E-mail: abadal@unimap.edu.my [Centre of Excellence for Unmanned Aerial Systems, Universiti Malaysia Perlis, 01000 Kangar, Perlis (Malaysia); and others

    2014-12-04

    This paper explain the analysis of internal air flow velocity of a bladeless vertical takeoff and landing (VTOL) Micro Aerial Vehicle (MAV) hemisphere body. In mechanical design, before produce a prototype model, several analyses should be done to ensure the product's effectiveness and efficiency. There are two types of analysis method can be done in mechanical design; mathematical modeling and computational fluid dynamic. In this analysis, I used computational fluid dynamic (CFD) by using SolidWorks Flow Simulation software. The idea came through to overcome the problem of ordinary quadrotor UAV which has larger size due to using four rotors and the propellers are exposed to environment. The bladeless MAV body is designed to protect all electronic parts, which means it can be used in rainy condition. It also has been made to increase the thrust produced by the ducted propeller compare to exposed propeller. From the analysis result, the air flow velocity at the ducted area increased to twice the inlet air. This means that the duct contribute to the increasing of air velocity.

  12. IMPROVEMENT OF BODY SHOP MANAGING AS A PART OF VEHICLE IMPORTERS CENTER

    Directory of Open Access Journals (Sweden)

    Vasil Stamboliski

    2014-12-01

    Full Text Available The dynamic rhythm of living in today’s contemporary surroundings can not be considered without the use of personal and commercial vehicles, for transport of passengers and cargo. This means that every manufacturer in this segment, in their departments for development, find a way to increase their participation in the market. Since the race with time, for promoting new models on the market, not always is in positive relation with the profit which the manufacturer plans to achieve, issues the manufacturer’s focus in the after-sale activities. The body shop with its service, as part of the after-sale activities, brings the client satisfaction to a higher level and of course contributes to realization of higher profit of the company. The setting of the equipment and the staff management, the analysis of the number of entries and realized working hours in the body shop of an importer centre are the central topic/main subject for the author in this paper work. Finding the key factors, as well as the possibility for implementation of the key factors, would reflect increased number of entries, increased number of realized working hours and possibility for improving of the existing system of managing.

  13. Internal air flow analysis of a bladeless micro aerial vehicle hemisphere body using computational fluid dynamic

    International Nuclear Information System (INIS)

    This paper explain the analysis of internal air flow velocity of a bladeless vertical takeoff and landing (VTOL) Micro Aerial Vehicle (MAV) hemisphere body. In mechanical design, before produce a prototype model, several analyses should be done to ensure the product's effectiveness and efficiency. There are two types of analysis method can be done in mechanical design; mathematical modeling and computational fluid dynamic. In this analysis, I used computational fluid dynamic (CFD) by using SolidWorks Flow Simulation software. The idea came through to overcome the problem of ordinary quadrotor UAV which has larger size due to using four rotors and the propellers are exposed to environment. The bladeless MAV body is designed to protect all electronic parts, which means it can be used in rainy condition. It also has been made to increase the thrust produced by the ducted propeller compare to exposed propeller. From the analysis result, the air flow velocity at the ducted area increased to twice the inlet air. This means that the duct contribute to the increasing of air velocity

  14. 轻轨车辆的车体材料探讨%Discussion of Light Rail Vehicles Body's Materials

    Institute of Scientific and Technical Information of China (English)

    冯军; 梁爽

    2012-01-01

    The development course and present situation of light rail vehicles at home and abroad were introduced in this paper. At the meantime, based on comparing the technical an economical features of weather-carbon steels, resistant steels, stainless steels, aluminium alloys and aero compound materials, pointed out that aluminium alloys are suitable to car body material of LRV. Furthermore, prospects of aero compound materials' use were looked forward to.%介绍了轻轨车辆的现状、发展历史及其车体承载结构用材料的特点,基于轨道车辆车体材料(普通碳素钢、耐候钢、不锈钢、铝合金及航空复合材料)的技术性和经济性的比较,指出铝合金是目前生产轻轨车辆较为合适的材料,同时对新型航空材料的使用前景进行了展望.

  15. A principal components approach to parent-to-newborn body composition associations in South India

    Directory of Open Access Journals (Sweden)

    Hill Jacqueline C

    2009-02-01

    Full Text Available Abstract Background Size at birth is influenced by environmental factors, like maternal nutrition and parity, and by genes. Birth weight is a composite measure, encompassing bone, fat and lean mass. These may have different determinants. The main purpose of this paper was to use anthropometry and principal components analysis (PCA to describe maternal and newborn body composition, and associations between them, in an Indian population. We also compared maternal and paternal measurements (body mass index (BMI and height as predictors of newborn body composition. Methods Weight, height, head and mid-arm circumferences, skinfold thicknesses and external pelvic diameters were measured at 30 ± 2 weeks gestation in 571 pregnant women attending the antenatal clinic of the Holdsworth Memorial Hospital, Mysore, India. Paternal height and weight were also measured. At birth, detailed neonatal anthropometry was performed. Unrotated and varimax rotated PCA was applied to the maternal and neonatal measurements. Results Rotated PCA reduced maternal measurements to 4 independent components (fat, pelvis, height and muscle and neonatal measurements to 3 components (trunk+head, fat, and leg length. An SD increase in maternal fat was associated with a 0.16 SD increase (β in neonatal fat (p Conclusion Principal components analysis is a useful method to describe neonatal body composition and its determinants. Newborn adiposity is related to maternal nutritional status and parity, while newborn length is genetically determined. Further research is needed to understand mechanisms linking maternal pelvic size to fetal growth and the determinants and implications of the components (trunk v leg length of fetal skeletal growth.

  16. Identification of common features of vehicle motion under drowsy/distracted driving: A case study in Wuhan, China.

    Science.gov (United States)

    Chen, Zhijun; Wu, Chaozhong; Zhong, Ming; Lyu, Nengchao; Huang, Zhen

    2015-08-01

    Drowsy/distracted driving has become one of the leading causes of traffic crash. Only certain particular drowsy/distracted driving behaviors have been studied by previous studies, which are mainly based on dedicated sensor devices such as bio and visual sensors. The objective of this study is to extract the common features for identifying drowsy/distracted driving through a set of common vehicle motion parameters. An intelligent vehicle was used to collect vehicle motion parameters. Fifty licensed drivers (37 males and 13 females, M=32.5 years, SD=6.2) were recruited to carry out road experiments in Wuhan, China and collecting vehicle motion data under four driving scenarios including talking, watching roadside, drinking and under the influence of drowsiness. For the first scenario, the drivers were exposed to a set of questions and asked to repeat a few sentences that had been proved valid in inducing driving distraction. Watching roadside, drinking and driving under drowsiness were assessed by an observer and self-reporting from the drivers. The common features of vehicle motions under four types of drowsy/distracted driving were analyzed using descriptive statistics and then Wilcoxon rank sum test. The results indicated that there was a significant difference of lateral acceleration rates and yaw rate acceleration between "normal driving" and drowsy/distracted driving. Study results also shown that, under drowsy/distracted driving, the lateral acceleration rates and yaw rate acceleration were significantly larger from the normal driving. The lateral acceleration rates were shown to suddenly increase or decrease by more than 2.0m/s(3) and the yaw rate acceleration by more than 2.5°/s(2). The standard deviation of acceleration rate (SDA) and standard deviation of yaw rate acceleration (SDY) were identified to as the common features of vehicle motion for distinguishing the drowsy/distracted driving from the normal driving. In order to identify a time window for

  17. Integrated Entry Guidance for Reusable Launch Vehicle

    Institute of Scientific and Technical Information of China (English)

    NING Guo-dong; ZHANG Shu-guang; FANG Zhen-ping

    2007-01-01

    A method for the implementation of integrated three-degree-of-freedom constrained entry guidance for reusable launch vehicle is presented. Given any feasible entry conditions, terminal area energy management interface conditions, and the reference trajectory generated onboard then, the method can generate a longitudinal guidance profile rapidly, featuring linear quadratic regular method and a proportional-integral-derivative tracking law with time-varying gains, which satisfies all the entry corridor constraints and meets the requirements with high precision. Afterwards, by utilizing special features of crossrange parameter, establishing bank-reversal corridor,and determining bank-reversals according to dynamically adjusted method, the algorithm enables the lateral entry guidance system to fly a wide range of missions and provides reliable and good performance in the presence of significant aerodynamic modeling uncertainty.Fast trajectory guidance profiles and simulations with a reusable launch vehicle model for various missions and aerodynamic uncertainties are presented to demonstrate the capacity and reliability of this method.

  18. Experimental Evaluation of the Effect of Angle-of-attack on the External Aerodynamics and Mass Capture of a Symmetric Three-engine Air-breathing Launch Vehicle Configuration at Supersonic Speeds

    Science.gov (United States)

    Kim, Hyun D.; Frate, Franco C.

    2001-01-01

    A subscale aerodynamic model of the GTX air-breathing launch vehicle was tested at NASA Glenn Research Center's 10- by 10-Foot Supersonic Wind Tunnel from Mach 2.0 to 3.5 at various angles-of-attack. The objective of the test was to investigate the effect of angle-of-attack on inlet mass capture, inlet diverter effectiveness, and the flowfield at the cowl lip plane. The flow-through inlets were tested with and without boundary-layer diverters. Quantitative measurements such as inlet mass flow rates and pitot-pressure distributions in the cowl lip plane are presented. At a 3deg angle-of-attack, the flow rates for the top and side inlets were within 8 percent of the zero angle-of-attack value, and little distortion was evident at the cowl lip plane. Surface oil flow patterns showing the shock/boundary-layer interaction caused by the inlet spikes are shown. In addition to inlet data, vehicle forebody static pressure distributions, boundary-layer profiles, and temperature-sensitive paint images to evaluate the boundary-layer transition are presented. Three-dimensional parabolized Navier-Stokes computational fluid dynamics calculations of the forebody flowfield are presented and show good agreement with the experimental static pressure distributions and boundary-layer profiles. With the boundary-layer diverters installed, no adverse aerodynamic phenomena were found that would prevent the inlets from operating at the required angles-of-attack. We recommend that phase 2 of the test program be initiated, where inlet contraction ratio and diverter geometry variations will be tested.

  19. 速度场演化结构非定常气动力%EVOLUTION OF UNSTEADY AERODYNAMIC FORCES FOR BODIES FROM FLOW MAPS

    Institute of Scientific and Technical Information of China (English)

    张伟; 葛耀君

    2009-01-01

    The equations of unsteady aerodynamic forces of the body emerged in fluids were derived from the basic equations of fluid mechanics. The equations were suitable not only for single connected fluid domain around bridge decks but also for multiple connected fluid domains around multiple separated box girders after using the Ostrovski-Gauss formula to change the integral from volume to surface. At the same time, the simplified equations were obtained for the sample rate of flow maps is low. The flow maps around the square cylinder were obtained in the Reynolds number of 22,000 using both numerical simulation and Particle Image Velocimetry which coincide with the results of experiments carded by other researchers. The aerodynamic forces were obtained using the flow map to validate the equations. The results show that it has a good agreement in damping force coefficient but poor in lifting force coefficient. When the equations were simplified to neglect the velocity difference in time, the results agree well. While the equations were simplified further to use only limited velocity data around only one segment, the results differs greatly with the results from original equations. Furthermore, the flow maps around the twin box girders from numerical simulation were also used to validate the equations. The results were the same with that of square cylinder, that is to say, good in damping force coefficient but poor in lifting force coefficient. At last, the reason of such discrepancies was analyzed.%从流体力学的基本公式出发,获得了结构受流场作用的非定常气动力公式.在积分降阶时,采用奥高公式使得非定常气动力公式不仅能够适用于单箱桥梁断面周围的流场,也能够适用于多箱分离断面周围的多连通流场.同时,由于试验流场数据的采样频率较低,因此给出了仅忽略时间项的简化公式以及忽略时间并仅依照有限区域流场进行计算的简化公式.采用数值模

  20. An Matching Method for Vehicle-borne Panoramic Image Sequence Based on Adaptive Structure from Motion Feature

    Directory of Open Access Journals (Sweden)

    ZHANG Zhengpeng

    2015-10-01

    Full Text Available Panoramic image matching method with the constraint condition of local structure from motion similarity feature is an important method, the process requires multivariable kernel density estimations for the structure from motion feature used nonparametric mean shift. Proper selection of the kernel bandwidth is a critical step for convergence speed and accuracy of matching method. Variable bandwidth with adaptive structure from motion feature for panoramic image matching method has been proposed in this work. First the bandwidth matrix is defined using the locally adaptive spatial structure of the sampling point in spatial domain and optical flow domain. The relaxation diffusion process of structure from motion similarity feature is described by distance weighting method of local optical flow feature vector. Then the expression form of adaptive multivariate kernel density function is given out, and discusses the solution of the mean shift vector, termination conditions, and the seed point selection method. The final fusions of multi-scale SIFT the features and structure features to establish a unified panoramic image matching framework. The sphere panoramic images from vehicle-borne mobile measurement system are chosen such that a comparison analysis between fixed bandwidth and adaptive bandwidth is carried out in detail. The results show that adaptive bandwidth is good for case with the inlier ratio changes and the object space scale changes. The proposed method can realize the adaptive similarity measure of structure from motion feature, improves the correct matching points and matching rate, experimental results have shown our method to be robust.

  1. Body image disturbance in binge eating disorder: a comparison of obese patients with and without binge eating disorder regarding the cognitive, behavioral and perceptual component of body image.

    Science.gov (United States)

    Lewer, Merle; Nasrawi, Nadia; Schroeder, Dorothea; Vocks, Silja

    2016-03-01

    Whereas the manifestation of body image disturbance in binge eating disorder (BED) has been intensively investigated concerning the cognitive-affective component, with regard to the behavioral and the perceptual components of body image disturbance in BED, research is limited and results are inconsistent. Therefore, the present study assessed body image disturbance in BED with respect to the different components of body image in a sample of obese females (n = 31) with BED compared to obese females without an eating disorder (n = 28). The Eating Disorder Inventory-2, the Eating Disorder Examination-Questionnaire, the Body Image Avoidance Questionnaire and the Body Checking Questionnaire as well as a Digital Photo Distortion Technique based on a picture of each participant taken under standardized conditions were employed. Using two-sample t tests, we found that the participants with BED displayed significantly greater impairments concerning the cognitive-affective component of body image than the control group. Concerning the behavioral component, participants with BED reported more body checking and avoidance behavior than the controls, but group differences failed to reach significance after the Bonferroni corrections. Regarding the perceptual component, a significant group difference was found for the perceived "ideal" figure, with the individuals suffering from BED displaying a greater wish for a slimmer ideal figure than the control group. These results support the assumption that body image disturbance is a relevant factor in BED, similar to other eating disorders. PMID:26178486

  2. Body image disturbance in binge eating disorder: a comparison of obese patients with and without binge eating disorder regarding the cognitive, behavioral and perceptual component of body image.

    Science.gov (United States)

    Lewer, Merle; Nasrawi, Nadia; Schroeder, Dorothea; Vocks, Silja

    2016-03-01

    Whereas the manifestation of body image disturbance in binge eating disorder (BED) has been intensively investigated concerning the cognitive-affective component, with regard to the behavioral and the perceptual components of body image disturbance in BED, research is limited and results are inconsistent. Therefore, the present study assessed body image disturbance in BED with respect to the different components of body image in a sample of obese females (n = 31) with BED compared to obese females without an eating disorder (n = 28). The Eating Disorder Inventory-2, the Eating Disorder Examination-Questionnaire, the Body Image Avoidance Questionnaire and the Body Checking Questionnaire as well as a Digital Photo Distortion Technique based on a picture of each participant taken under standardized conditions were employed. Using two-sample t tests, we found that the participants with BED displayed significantly greater impairments concerning the cognitive-affective component of body image than the control group. Concerning the behavioral component, participants with BED reported more body checking and avoidance behavior than the controls, but group differences failed to reach significance after the Bonferroni corrections. Regarding the perceptual component, a significant group difference was found for the perceived "ideal" figure, with the individuals suffering from BED displaying a greater wish for a slimmer ideal figure than the control group. These results support the assumption that body image disturbance is a relevant factor in BED, similar to other eating disorders.

  3. Clinical features of muscle dysmorphia among males with body dysmorphic disorder.

    Science.gov (United States)

    Pope, Courtney G; Pope, Harrison G; Menard, William; Fay, Christina; Olivardia, Roberto; Phillips, Katharine A

    2005-12-01

    Muscle dysmorphia - a pathological preoccupation with muscularity - appears to be a form of body dysmorphic disorder (BDD) with a focus on muscularity. However, little is known about muscle dysmorphia in men with BDD, and no study has compared men with BDD who do and do not report muscle dysmorphia. To explore this issue, we reviewed the histories of 63 men with BDD; we compared those rated as having a history of muscle dysmorphia with those who had BDD but not muscle dysmorphia in several domains. The 14 men with muscle dysmorphia resembled the 49 comparison men in demographic features, BDD severity, delusionality, and number of non-muscle-related body parts of concern. However, those with muscle dysmorphia were more likely to have attempted suicide, had poorer quality of life, and had a higher frequency of any substance use disorder and anabolic steroid abuse. Thus, muscle dysmorphia was associated with greater psychopathology. PMID:17075613

  4. Aerodynamic Characteristics Simulation Study of Air-launched Launch Vehicle in the Process of Rocket Separating from Plane%空射火箭箭机分离过程气动特性仿真

    Institute of Scientific and Technical Information of China (English)

    屈亮; 张登成; 张艳华; 胡孟权; 李达

    2013-01-01

    为研究内装式空中发射运载火箭在箭机分离过程中的气动特性尤其是大迎角情况下的气动变化规律,应用计算流体力学(CFD)软件中的k-w模型对火箭气动特性进行了仿真研究,得到火箭气动特性随马赫数和迎角的变化规律,同时对改进后的火箭模型进行气动特性分析.仿真结果表明:发现火箭尾部改进成收敛-扩张型喷管可使火箭下落初期有一个抬头力矩,有利于运载火箭初期快速调整姿态;当快到达预期点火姿态时,由于气动力作用点后移产生的与角速度方向相反的力矩,可迫使运载火箭稳定,从而更容易地捕捉到点火角度,并保证点火时的姿态稳定.%For studying the aerodynamic characteristics of rocket in the process of the rocket separating from the plane internally carried air-launched launch vehicle,especially when the rocket is at high angle of attack,CFD is applied to the simulation of rocket aerodynamic characteristics.Based on the improvement of rocket shape,the rocket aerodynamic characteristics with Mach number and angle of attack can be obtained.The analysis of the aerodynamic characteristics of the improved rocket model shows that the rocket tail improved into a convergent nozzle is of great benefit to the attitude adjustment.These analyses provide a theoretical foundation for the further research on rocket attitude stabilization and track design.

  5. A cross-cultural study investigating body features associated with male adolescents' body dissatisfaction in Australia, China, and Malaysia.

    Science.gov (United States)

    Mellor, David; Hucker, Alice; Waterhouse, Monique; binti Mamat, Norul Hidayah; Xu, Xiaoyan; Cochrane, Jamie; McCabe, Marita; Ricciardelli, Lina

    2014-11-01

    This study investigated how dissatisfaction with particular aspects of the body was associated with overall body dissatisfaction among male adolescents in Western and Asian cultures. One hundred and six Malaysian Malays, 55 Malaysian Chinese, 195 Chinese from China, and 45 non-Asian Australians aged 12 to 19 years completed a questionnaire assessing dissatisfaction with their overall body and dissatisfaction with varying aspects of their body. Dissatisfaction with the face, height, and hair was positively correlated with overall body dissatisfaction among Malaysian Malays after body mass index, age and dissatisfaction with body areas typically included in measures (weight/shape, upper, middle, and lower body, and muscles) had been controlled for. Dissatisfaction with the face was positively correlated with overall body dissatisfaction among Malaysian Chinese. These findings demonstrate the differences in body focus for males from different cultures and the importance of using assessment measures that address all possible areas of body focus. PMID:24707036

  6. Comparative Study of Feature Extraction Components from Several Wavelet Transformations for Ornamental Plants

    Directory of Open Access Journals (Sweden)

    Kohei Arai

    2014-02-01

    Full Text Available Human has a duty to preserve the nature, preserving the plant is one of the examples. This research emphasis on ornamental plant that has functionality not only as ornament plant but also as a medicinal plant. Purpose of this research is to find the best of the particular feature extraction components from several wavelet transformations. It consists of Daubechies, Dyadic, and Dual-tree complex wavelet transformation. Dyadic and Dual-tree complex wavelet transformations have shift invariant property. While Daubechies is a standard wavelet transform that widely used for many applications. This comparison is utilizing leaf image datasets from ornamental plants. From the experiments, obtained that best classification performance attained by Dual-tree complex wavelet transformation with 96.66% of overall performance result.

  7. Detecting Combustion and Flow Features In Situ Using Principal Component Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, David [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Grout, Ray W. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Fabian, Nathan D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bennett, Janine Camille [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2009-03-01

    This report presents progress on identifying and classifying features involving combustion in turbulent flow using principal component analysis (PCA) and k-means clustering using an in situ analysis framework. We describe a process for extracting temporally- and spatially-varying information from the simulation, classifying the information, and then applying the classification algorithm to either other portions of the simulation not used for training the classifier or further simulations. Because the regions classified as being of interest take up a small portion of the overall simulation domain, it will consume fewer resources to perform further analysis or save these regions at a higher fidelity than previously possible. The implementation of this process is partially complete and results obtained from PCA of test data is presented that indicates the process may have merit: the basis vectors that PCA provides are significantly different in regions where combustion is occurring and even when all 21 species of a lifted flame simulation are correlated the computational cost of PCA is minimal. What remains to be determined is whether k-means (or other) clustering techniques will be able to identify combined combustion and flow features with an accuracy that makes further characterization of these regions feasible and meaningful.

  8. Nontangent, Developed Contour Bulkheads for a Wing-Body Single Stage Launch Vehicle

    Science.gov (United States)

    Wu, K. Chauncey; Lepsch, Roger A., Jr.

    1999-01-01

    Dry weights for a SSTO vehicle which incorporates nontangent, developed contour bulkheads are estimated and compared to a baseline vehicle with 1.41 4 aspect ratio ellipsoidal bulkheads, Weights, volumes and heights of optimized bulkhead designs are computed using a preliminary design bulkhead analysis code. The dry weight of a vehicle which incorporates the optimized bulkheads is predicted using a vehicle weights and sizing code. Two optimization approaches are employed. A structural-level method, where the vehicle s three major bulkhead regions are optimized separately and then incorporated into a model for computation of the vehicle dry weight, predicts a reduction of 4365 Ib (2.2 percent) from the 200,679 Ib baseline vehicle dry weight. In the second, vehicle-level, approach, the vehicle dry weight is the objective function for the optimization. During the vehicle- level analysis, modified bulkhead designs are first analyzed, then incorporated into the weights model for computation of a dry weight. The optimizer simultaneously manipulates design variables for all three bulkheads to reduce the dry weight. The vehicle-level analysis predicts a dry weight reduction of 5129 Ib, a 2.6 percent reduction from the baseline value. These results suggest that nontangent, developed contour bulkheads may provide substantial weight savings for SSTO vehicles.

  9. Discrete vortex method simulations of aerodynamic admittance in bridge aerodynamics

    DEFF Research Database (Denmark)

    Rasmussen, Johannes Tophøj; Hejlesen, Mads Mølholm; Larsen, Allan;

    The meshless and remeshed Discrete Vortex Method (DVM) has been widely used in academia and by the industry to model two-dimensional flow around bluff bodies. The implementation “DVMFLOW” [1] is used by the bridge design company COWI to determine and visualise the flow field around bridge sections......, and to determine aerodynamic forces and the corresponding flutter limit. A simulation of the three-dimensional bridge responseto turbulent wind is carried out by quasi steady theory by modelling the bridge girder as a line like structure [2], applying the aerodynamic load coefficients found from the current version...... of DVMFLOW in a strip wise fashion. Neglecting the aerodynamic admittance, i.e. the correlation of the instantaneous lift force to the turbulent fluctuations in the vertical velocities, leads to higher response to high frequency atmospheric turbulence than would be obtained from wind tunnel tests....

  10. Discrete vortex method simulations of aerodynamic admittance in bridge aerodynamics

    DEFF Research Database (Denmark)

    Rasmussen, Johannes Tophøj; Hejlesen, Mads Mølholm; Larsen, Allan;

    velocity spectra are found in good agreement with the target spectra. The aerodynamic admittance of the structure is measured by sampling vertical velocities immediately upstream of the structure and the lift forces on the structure. The method is validated against the analytic solution for the admittance......The meshless and remeshed Discrete Vortex Method (DVM) has been widely used in academia and by the industry to model two-dimensional flow around bluff bodies. The implementation “DVMFLOW” [1] is used by the bridge design company COWI to determine and visualise the flow field around bridge sections......, and to determine aerodynamic forces and the corresponding flutter limit. A simulation of the three-dimensional bridge responseto turbulent wind is carried out by quasi steady theory by modelling the bridge girder as a line like structure [2], applying the aerodynamic load coefficients found from the current version...

  11. Simultaneous determination of active component and vehicle penetration from F-DPPC liposomes into porcine skin layers.

    Science.gov (United States)

    Mahrhauser, Denise-Silvia; Reznicek, Gottfried; Gehrig, Sebastian; Geyer, Antonia; Ogris, Manfred; Kieweler, Ruth; Valenta, Claudia

    2015-11-01

    Liposomes have been used as innovative delivery vehicles on skin for a number of years due to their positive influence on skin penetration. However, until now it is not entirely clear how and by which mechanism enhancement is achieved. In the present study, the skin permeation of a model substance incorporated into liposomes and a control formulation was compared to study the influence of the vehicle in Franz-type diffusion cell experiments. Furthermore, the penetration depths of both components were studied by simultaneous determination of the active substance and the vehicle component during tape stripping studies and horizontal sectioning. For these purposes we prepared liposomes with 1-palmitoyl-2-(16-fluoropalmitoyl)-sn-glycero-3-phosphocholine (F-DPPC), the monofluorinated analogue of dipalmitoylphosphaditylcholine (DPPC) loaded with sodium fluorescein (SoFl). A sodium-fluorescein solution was used as control formulation. While the semi-solid F-DPPC liposomes and the SoFl-solution performed equally well with similar permeation profiles during skin diffusion experiments, superior penetrated amounts of SoFl into the stratum corneum (SC) from F-DPPC liposomes compared to the SoFl-solution were observed possibly due to a "push" exerted by the vehicle F-DPPC. We also showed that SoFl penetrated through SC into the viable epidermis. PMID:26493713

  12. 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.

  13. Abort performance for a winged-body single-stage to orbit vehicle. M.S. Thesis - George Washington Univ.

    Science.gov (United States)

    Lyon, Jeffery A.

    1995-01-01

    Optimal control theory is employed to determine the performance of abort to orbit (ATO) and return to launch site (RTLS) maneuvers for a single-stage to orbit vehicle. The vehicle configuration examined is a seven engine, winged-body vehicle, that lifts-off vertically and lands horizontally. The abort maneuvers occur as the vehicle ascends to orbit and are initiated when the vehicle suffers an engine failure. The optimal control problems are numerically solved in discretized form via a nonlinear programming (NLP) algorithm. A description highlighting the attributes of this NLP method is provided. ATO maneuver results show that the vehicle is capable of ascending to orbit with a single engine failure at lift-off. Two engine out ATO maneuvers are not possible from the launch pad, but are possible after launch when the thrust to weight ratio becomes sufficiently large. Results show that single engine out RTLS maneuvers can be made for up to 180 seconds after lift-off and that there are scenarios for which RTLS maneuvers should be performed instead of ATP maneuvers.

  14. Design of the simulator of the motion of the unmanned autonomous underwater vehicle as a component of the simulation complex

    OpenAIRE

    Sirivchuk, Andriy S.

    2015-01-01

    The study of the automatic control system for the autonomous underwater vehicle is a complex and expensive process. Conducting experiments in test pools and open water may cause damage to expensive equipment. Therefore, the use of simulation complexes is a more efficient approach. The article aim is to describe the structure of the simulation complex designed for the study of the quality of the automatic control system. The main component of this complex is the simulator of the motion of the ...

  15. THE AERODYNAMIC ANALYSIS OF THE PROFILES FOR FLYING WINGS

    Directory of Open Access Journals (Sweden)

    Vasile PRISACARIU

    2013-01-01

    Full Text Available The possibility of using an un-piloted aerial vector is determined by the aerodynamic characteristics and performances. The design for a tailless unmanned aerial vehicles starts from defining the aerial vector mission and implies o series of geometrical and aerodynamic aspects for stability. This article proposes to remark the aerodynamic characteristics of three profiles used at flying wing airship through 2D software analysis.

  16. Aerodynamic and Electromagnetic Characteristics Research of High-altitude Long-endurance Early Warning Unmanned Aerial Vehicles%高空长航时无人预警机气动及电磁特性研究

    Institute of Scientific and Technical Information of China (English)

    任武; 周洲; 王正平

    2012-01-01

    高空长航时无人预警机具有反应迅速、成本低廉、覆盖范围广等优点,是侦察卫星、高空飞艇等侦察平台的重要补充.基于天线特性,提出两种将柱面天线与高空长航时无人机融合的布局形式,将雷达反射面天线布置于无人机中段,并分析两种布局在气动及电磁特性的差异,为此类特种高空长航时无人预警机的设计提供了一定的理论依据.%The high-altitude long-endurance ( HALE) early warning unmanned aerial vehicles ( UAV) had become an important complementarity of reconnaissance satellite and high-altitude airship as reconnaissance platform, since it was excellence in quick response, low cost, vast coverage area, etc. Based on the character of antenna, two high-altitude long-endurance early warning unmanned aerial vehicles layouts combined with antenna which was set in the middle of the whole plane were put forward. And then analyzed the aerodynamic and electromagnetic character difference between the two layouts. A certain theory evidence is provided for the design of these special high altitude long-endurance early warning aircraft.

  17. DETERMINATION OF VEHICLE COMPONENTS FATIGUE LIFE BASED ON FEA METHOD AND EXPERIMENTAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    Arif Senol SENER

    2012-01-01

    Full Text Available In this study, construction and standardization of a track for performing fatigue and reliability test of light commercial vehicles is described. For the design and process verification of the company’s vehicles one test track is defined. A questionnaire was used to determine the average usage of light commercial vehicles in Turkey. Fatigue characteristics of Turkish roads were determined by analyzing fifty different roads and this article focuses on defining the load spectrum and equivalent fatigue damage of the leaf spring resulting from the accelerated test route. Fatigue analysis and estimated lifespan of the part were calculated using Finite Element Analyses and verified by the Palmgren-Miner rule. When the customer profile is taken into consideration; Turkish customer automotive usage profile, the aim of usage of this kind of vehicle (LCV, fatigue characteristics of Turkish roads for this vehicle were determined and around Bursa one accelerated test tracks were formed for the reliability and fatigue test for the related company, linear analysis executed on the FEA of the spring was more convenient were obtained.

  18. Effect of Dietary Phosphorus on the Growth and Body Components of Juvenile Synechogobius hasta

    Institute of Scientific and Technical Information of China (English)

    LUO Zhi; LI Xiaodong; GONG Shiyuan; XI Wenqiu; LI Yali

    2009-01-01

    The effect of dietary, phosphorus on the growth and body, components of juvenile Synechogobius hasta was determined. Different percentages of dietary phosphorus (0.63, 0.77, 0.93, 1.06, 1.22 and 1.36) were tested by feeding the fish (body weight, 15.81 g±0.32 g、20 individuals each group、3 groups each percentage) at a surplus of 5%-10% above sattation for 35d. Dietary phosphorus did not significantly affect the specific growth rate, feed intake, feed conversion ratio and protein efficiency rate. Nitro-gen retention was found to be the highest in fish ted the diet containing 1.06% of phosphorus; however, this was not significantly different from other diets. Fish fed the diet containing 0.93% of phosphorus showed the highest phosphorus retention; similar phos-phorus retention rates were found in fish fed the diets containing 0.77% and 1.06% of phosphorus. Fish fed the diet containing the highest percentage of dietary, phosphorus were found to contain the least whole body lipid, lower than fish ted other diets (P<0.05). The protein content increased from 18.59% to 19.55% (although not significant) with the decrease of body lipid content (P<0.05). The contents of the whole body ash, whole body phosphorus and vertebrae phosphorus increased with dietary, phosphorus percentage up to 1.06 (P<0.05), reaching a plateau after that. Dietary, phosphorus did not significantly influence the muscle components (protein, lipid and moisture). Condition factor and hepatosomatic index were the highest in fish fed the diet containing 0.63% of dietary phos-phorus; however, this was not significantly different from those of other diets. The second-order polynomial regression of phospho-rus retention against dietary phosphorus identified a breakpoint at 0.88% of dietary phosphorus. However, the dietary requirement of phosphorus for maintaining maximum phosphorus storage determined by broken-line analysis of the contents of whole body phos-phorus, and ash and vertebrae phosphorus was 1

  19. Integration of an Advanced Cryogenic Electric Propulsion System (ACEPS) to Aerodynamically Efficient Subsonic Transport Aircraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal defines innovative aerodynamic concepts and technology goals aimed at vehicle efficiency for future subsonic aircraft in the 2020 ? 2030 timeframe....

  20. Analysis of the wind influence on the aerodynamic drag in the case of a certain emplacement of the pantograph on the electric rail vehicles

    Directory of Open Access Journals (Sweden)

    Sorin ARSENE

    2015-03-01

    Full Text Available The wind gusts with high speed can negative affect the operation of the railway electric vehicles. These vehicles can achieve high performances, as long as the power supply is ensured, without discontinuities or interruptions in the process. This work aims at conducting an analysis regarding the wind influence with regard to the energy collector placed on the vehicle bodywork taking in account a certain positioning of the active pantograph. To this end, in a first step, the EP3 pantograph which was raised to its maximum working height was 3-D modeled. As regards the simulation, we consider the case in which the equipment is placed on the vehicle so that the angle formed by the articulation of the arms is pointing in the direction of the air flow. The simulation is carried out for different points of the angles ranging between [0o, 180o] at the relative velocity of the fluid of 0m / s, 10m / s, 20m / s and 30m / s.

  1. 论身势语的文化特征%The Cultural Features of Body Language

    Institute of Scientific and Technical Information of China (English)

    刘娅婷

    2005-01-01

    Body language belongs to the scope of non-verbal communication,and it plays an important part in complementing,stressing,enhancing,symbolizing and substituting utterance meaning.It argues that body language,which is the carrier of cultures,and different in meanings,behavior,and countries,has its own cultural features that are necessary and important in Cross-cultural communication.%身势语属于非语言交际的范畴,但在语言交际中有着补充说明强调、增加、象征或替代等含义,因此对身势语的作用不可忽视.身势语是文化的载体,不同的国家地区,有不同的行为方式,有着不同的语义.所以,研究身势语的文化特征对外语研究工作和跨文化交流有重要的影响和意义.

  2. Recent Progress on the Key Materials and Components for Proton Exchange Membrane Fuel Cells in Vehicle Applications

    Directory of Open Access Journals (Sweden)

    Cheng Wang

    2016-07-01

    Full Text Available Fuel cells are the most clean and efficient power source for vehicles. In particular, proton exchange membrane fuel cells (PEMFCs are the most promising candidate for automobile applications due to their rapid start-up and low-temperature operation. Through extensive global research efforts in the latest decade, the performance of PEMFCs, including energy efficiency, volumetric and mass power density, and low temperature startup ability, have achieved significant breakthroughs. In 2014, fuel cell powered vehicles were introduced into the market by several prominent vehicle companies. However, the low durability and high cost of PEMFC systems are still the main obstacles for large-scale industrialization of this technology. The key materials and components used in PEMFCs greatly affect their durability and cost. In this review, the technical progress of key materials and components for PEMFCs has been summarized and critically discussed, including topics such as the membrane, catalyst layer, gas diffusion layer, and bipolar plate. The development of high-durability processing technologies is also introduced. Finally, this review is concluded with personal perspectives on the future research directions of this area.

  3. Disentangling the associations between parental BMI and offspring body composition using the four‐component model

    Science.gov (United States)

    Grijalva‐Eternod, Carlos; Cortina‐Borja, Mario; Williams, Jane; Fewtrell, Mary; Wells, Jonathan

    2016-01-01

    ABSTRACT Objectives This study sets out to investigate the intergenerational associations between the body mass index (BMI) of parents and the body composition of their offspring. Methods The cross‐sectional data were analyzed for 511 parent–offspring trios from London and south‐east England. The offspring were aged 5–21 years. Parental BMI was obtained by recall and offspring fat mass and lean mass were obtained using the four‐component model. Multivariable regression analysis, with multiple imputation for missing paternal values was used. Sensitivity analyses for levels of non‐paternity were conducted. Results A positive association was seen between parental BMI and offspring BMI, fat mass index (FMI), and lean mass index (LMI). The mother's BMI was positively associated with the BMI, FMI, and LMI z‐scores of both daughters and sons and of a similar magnitude for both sexes. The father's BMI showed similar associations to the mother's BMI, with his son's BMI, FMI, and LMI z‐scores, but no association with his daughter. Sensitivity tests for non‐paternity showed that maternal coefficients remained greater than paternal coefficients throughout but there was no statistical difference at greater levels of non‐paternity. Conclusions We found variable associations between parental BMI and offspring body composition. Associations were generally stronger for maternal than paternal BMI, and paternal associations appeared to differ between sons and daughters. In this cohort, the mother's BMI was statistically significantly associated with her child's body composition but the father's BMI was only associated with the body composition of his sons. Am. J. Hum. Biol. 28:524–533, 2016. © 2016 The Authors American Journal of Human Biology Published by Wiley Periodicals, Inc. PMID:26848813

  4. Evaluation of selected drive components for a flywheel-powered commuter vehicle, Phase I. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1977-06-30

    The Phase I tasks of a project for the development of an energy storing flywheel powerplant for a short-range commuter vehicle were directed towards evaluating and characterizing specific technologies associated with the flywheel propulsion system that were considered to be critical to the successful development of the proposed commuter car. The vehicle flywheel would be designed to operate between 20,000 and 41,000 rpm, storing a total of 16 kw-hrs at the maximum speed of 41,000 rpm. Vertical spin axes were selected so that normal vehicle cornering would not induce gyroscopic forces on the flywheel bearings. Two rotors would turn in opposite directions so that any gyroscopic forces produced by vehicle pitch or roll motions would be balanced within the flywheel assembly and not reflected to the chassis. Each rotor would be assembled from six identical modules stacked on a common shaft, each module being of multi-rim construction. In Phase I, the rotor testing was limited to the outer (most highly stressed) rims from a single module. The bearings and seals were tested under load conditions simulating those expected from a complete six module rotor. The flywheel system failed to achieve target speed and exhibited whip-like instability of the shaft/hub/spoke combination. The bearings and lubricant performed satisfactorily. The ferrofluidic centrifugal seals lacked the ability to withstand adequate pressure differentials. It is recommended that the project concentrate on the development of smaller, composite material flywheels suitable for use in hybrid vehicles. (LCL)

  5. Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS): features and potential applications in oncology

    NARCIS (Netherlands)

    Kwee, T.C.; Takahara, T.; Ochiai, Reiji; Nievelstein, R.A.J.; Luijten, P.R.

    2008-01-01

    Diffusion-weighted magnetic resonance imaging (DWI) provides functional information and can be used for the detection and characterization of pathologic processes, including malignant tumors. The recently introduced concept of “diffusion-weighted whole-body imaging with background body signal suppre

  6. Advanced Topics in Aerodynamics

    DEFF Research Database (Denmark)

    Filippone, Antonino

    1999-01-01

    "Advanced Topics in Aerodynamics" is a comprehensive electronic guide to aerodynamics,computational fluid dynamics, aeronautics, aerospace propulsion systems, design and relatedtechnology. We report data, tables, graphics, sketches,examples, results, photos, technical andscientific literature, for...

  7. Development of specific materials for the high power electronic components in electric vehicles

    Directory of Open Access Journals (Sweden)

    Kaabi Abderrahmen

    2013-11-01

    Full Text Available The powerchain in electric vehicles sets new demands on semi conductors and their packaging. The latter will be specifically addressed. The power density per cm2 in DC/DC or DC/AC converters requires a mastering of thermomecahnical aspects. The temperature cyling, the environment under the hood of the vehicles and the “hybrid” technology impose severe constraints on the assemblies which may be met by architectured substrates, new options for assemblies and efficient cooling systems. An optimised semi conductor substrate associating copper and invar in a will be developed, relying on roll bonding to produce the 3D architecture. Roll bonding may also be used to associate aluminium and iron to produce light laminates with a CEM performance.

  8. Effect of vehicles on topical application of aloe vera and arnica montana components.

    Science.gov (United States)

    Bergamante, Valentina; Ceschel, Gian Carlo; Marazzita, Sergio; Ronchi, Celestino; Fini, Adamo

    2007-10-01

    In this study two types of gels and microemulsions are investigated for their ability to dissolve, release, and induce the permeation of helenalin, a flavonoid responsible for the anti-inflammatory activity of arnica montana extract, and aloin, an anthrone-C-glucosyls with antibacterial activity present in aloe vera extract. The release of these agents from each vehicle was followed by HPLC, and transcutaneous permeation was examined using a modified Franz cell and a porcine skin membrane. The study showed that a microemulsion can be a good vehicle to increase the permeation of helenalin, while the gel formulation, containing Sepigel 305, proved able to reduce the release and permeation of aloin, with a consequent activity limited to the surface of application, without any permeation. This is in accordance with the necessity to avoid this process, since human skin fibroblasts can metabolize absorbed aloin into a structurally related compound that increases the sensitivity of skin to ultraviolet light.

  9. Optimizing components size of an extended range electric vehicle according to the use specifications

    OpenAIRE

    DEROLLEPOT, Romain; Weiss, Christine; Kolli, Zehir; Franke, Thomas; TRIGUI, Rochdi; Chlond, Bastian; ARMOOGUM, Jimmy; STARK, Juliane; Roman KLEMENTSCHITZ; Baumann, Michael; PELISSIER, Serge

    2014-01-01

    This paper presents a methodology to optimally design the drivetrain of an Extended Range Electric Vehicle (EREV) according to the use specifications from European mobility surveys. At first the analysis of car uses is carried out, and a process aiming to classify the car use profiles into different clusters is proposed. Clusters that could fit typical EREV use are selected and applied in a sizing methodology to design the battery and the Range Extender (RE). Using a validated simulation soft...

  10. Near term hybrid passenger vehicle development program. Phase I. Appendices C and D. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-01-01

    The derivation of and actual preliminary design of the Near Term Hybrid Vehicle (NTHV) are presented. The NTHV uses a modified GM Citation body, a VW Rabbit turbocharged diesel engine, a 24KW compound dc electric motor, a modified GM automatic transmission, and an on-board computer for transmission control. The following NTHV information is presented: the results of the trade-off studies are summarized; the overall vehicle design; the selection of the design concept and the base vehicle (the Chevrolet Citation), the battery pack configuration, structural modifications, occupant protection, vehicle dynamics, and aerodynamics; the powertrain design, including the transmission, coupling devices, engine, motor, accessory drive, and powertrain integration; the motor controller; the battery type, duty cycle, charger, and thermal requirements; the control system (electronics); the identification of requirements, software algorithm requirements, processor selection and system design, sensor and actuator characteristics, displays, diagnostics, and other topics; environmental system including heating, air conditioning, and compressor drive; the specifications, weight breakdown, and energy consumption measures; advanced technology components, and the data sources and assumptions used. (LCL)

  11. Stimulus-related independent component and voxel-wise analysis of human brain activity during free viewing of a feature film.

    Directory of Open Access Journals (Sweden)

    Juha M Lahnakoski

    Full Text Available Understanding how the brain processes stimuli in a rich natural environment is a fundamental goal of neuroscience. Here, we showed a feature film to 10 healthy volunteers during functional magnetic resonance imaging (fMRI of hemodynamic brain activity. We then annotated auditory and visual features of the motion picture to inform analysis of the hemodynamic data. The annotations were fitted to both voxel-wise data and brain network time courses extracted by independent component analysis (ICA. Auditory annotations correlated with two independent components (IC disclosing two functional networks, one responding to variety of auditory stimulation and another responding preferentially to speech but parts of the network also responding to non-verbal communication. Visual feature annotations correlated with four ICs delineating visual areas according to their sensitivity to different visual stimulus features. In comparison, a separate voxel-wise general linear model based analysis disclosed brain areas preferentially responding to sound energy, speech, music, visual contrast edges, body motion and hand motion which largely overlapped the results revealed by ICA. Differences between the results of IC- and voxel-based analyses demonstrate that thorough analysis of voxel time courses is important for understanding the activity of specific sub-areas of the functional networks, while ICA is a valuable tool for revealing novel information about functional connectivity which need not be explained by the predefined model. Our results encourage the use of naturalistic stimuli and tasks in cognitive neuroimaging to study how the brain processes stimuli in rich natural environments.

  12. Stimulus-Related Independent Component and Voxel-Wise Analysis of Human Brain Activity during Free Viewing of a Feature Film

    Science.gov (United States)

    Lahnakoski, Juha M.; Salmi, Juha; Jääskeläinen, Iiro P.; Lampinen, Jouko; Glerean, Enrico; Tikka, Pia; Sams, Mikko

    2012-01-01

    Understanding how the brain processes stimuli in a rich natural environment is a fundamental goal of neuroscience. Here, we showed a feature film to 10 healthy volunteers during functional magnetic resonance imaging (fMRI) of hemodynamic brain activity. We then annotated auditory and visual features of the motion picture to inform analysis of the hemodynamic data. The annotations were fitted to both voxel-wise data and brain network time courses extracted by independent component analysis (ICA). Auditory annotations correlated with two independent components (IC) disclosing two functional networks, one responding to variety of auditory stimulation and another responding preferentially to speech but parts of the network also responding to non-verbal communication. Visual feature annotations correlated with four ICs delineating visual areas according to their sensitivity to different visual stimulus features. In comparison, a separate voxel-wise general linear model based analysis disclosed brain areas preferentially responding to sound energy, speech, music, visual contrast edges, body motion and hand motion which largely overlapped the results revealed by ICA. Differences between the results of IC- and voxel-based analyses demonstrate that thorough analysis of voxel time courses is important for understanding the activity of specific sub-areas of the functional networks, while ICA is a valuable tool for revealing novel information about functional connectivity which need not be explained by the predefined model. Our results encourage the use of naturalistic stimuli and tasks in cognitive neuroimaging to study how the brain processes stimuli in rich natural environments. PMID:22496909

  13. Introduction to transonic aerodynamics

    CERN Document Server

    Vos, Roelof

    2015-01-01

    Written to teach students the nature of transonic flow and its mathematical foundation, this book offers a much-needed introduction to transonic aerodynamics. The authors present a quantitative and qualitative assessment of subsonic, supersonic, and transonic flow around bodies in two and three dimensions. The book reviews the governing equations and explores their applications and limitations as employed in modeling and computational fluid dynamics.  Some concepts, such as shock and expansion theory, are examined from a numerical perspective. Others, including shock-boundary-layer interaction, are discussed from a qualitative point of view. The book includes 60 examples and more than 200 practice problems. The authors also offer analytical methods such as Method of Characteristics (MOC) that allow readers to practice with the subject matter.  The result is a wealth of insight into transonic flow phenomena and their impact on aircraft design, including compressibility effects, shock and expansion waves, sho...

  14. Feature selection for wearable smartphone-based human activity recognition with able bodied, elderly, and stroke patients.

    Directory of Open Access Journals (Sweden)

    Nicole A Capela

    Full Text Available Human activity recognition (HAR, using wearable sensors, is a growing area with the potential to provide valuable information on patient mobility to rehabilitation specialists. Smartphones with accelerometer and gyroscope sensors are a convenient, minimally invasive, and low cost approach for mobility monitoring. HAR systems typically pre-process raw signals, segment the signals, and then extract features to be used in a classifier. Feature selection is a crucial step in the process to reduce potentially large data dimensionality and provide viable parameters to enable activity classification. Most HAR systems are customized to an individual research group, including a unique data set, classes, algorithms, and signal features. These data sets are obtained predominantly from able-bodied participants. In this paper, smartphone accelerometer and gyroscope sensor data were collected from populations that can benefit from human activity recognition: able-bodied, elderly, and stroke patients. Data from a consecutive sequence of 41 mobility tasks (18 different tasks were collected for a total of 44 participants. Seventy-six signal features were calculated and subsets of these features were selected using three filter-based, classifier-independent, feature selection methods (Relief-F, Correlation-based Feature Selection, Fast Correlation Based Filter. The feature subsets were then evaluated using three generic classifiers (Naïve Bayes, Support Vector Machine, j48 Decision Tree. Common features were identified for all three populations, although the stroke population subset had some differences from both able-bodied and elderly sets. Evaluation with the three classifiers showed that the feature subsets produced similar or better accuracies than classification with the entire feature set. Therefore, since these feature subsets are classifier-independent, they should be useful for developing and improving HAR systems across and within populations.

  15. Feature selection for wearable smartphone-based human activity recognition with able bodied, elderly, and stroke patients.

    Science.gov (United States)

    Capela, Nicole A; Lemaire, Edward D; Baddour, Natalie

    2015-01-01

    Human activity recognition (HAR), using wearable sensors, is a growing area with the potential to provide valuable information on patient mobility to rehabilitation specialists. Smartphones with accelerometer and gyroscope sensors are a convenient, minimally invasive, and low cost approach for mobility monitoring. HAR systems typically pre-process raw signals, segment the signals, and then extract features to be used in a classifier. Feature selection is a crucial step in the process to reduce potentially large data dimensionality and provide viable parameters to enable activity classification. Most HAR systems are customized to an individual research group, including a unique data set, classes, algorithms, and signal features. These data sets are obtained predominantly from able-bodied participants. In this paper, smartphone accelerometer and gyroscope sensor data were collected from populations that can benefit from human activity recognition: able-bodied, elderly, and stroke patients. Data from a consecutive sequence of 41 mobility tasks (18 different tasks) were collected for a total of 44 participants. Seventy-six signal features were calculated and subsets of these features were selected using three filter-based, classifier-independent, feature selection methods (Relief-F, Correlation-based Feature Selection, Fast Correlation Based Filter). The feature subsets were then evaluated using three generic classifiers (Naïve Bayes, Support Vector Machine, j48 Decision Tree). Common features were identified for all three populations, although the stroke population subset had some differences from both able-bodied and elderly sets. Evaluation with the three classifiers showed that the feature subsets produced similar or better accuracies than classification with the entire feature set. Therefore, since these feature subsets are classifier-independent, they should be useful for developing and improving HAR systems across and within populations.

  16. Low-Level Color and Texture Feature Extraction of Coral Reef Components

    Directory of Open Access Journals (Sweden)

    Ma. Sheila Angeli Marcos

    2003-06-01

    Full Text Available The purpose of this study is to develop a computer-based classifier that automates coral reef assessmentfrom digitized underwater video. We extract low-level color and texture features from coral images toserve as input to a high-level classifier. Low-level features for color were labeled blue, green, yellow/brown/orange, and gray/white, which are described by the normalized chromaticity histograms of thesemajor colors. The color matching capability of these features was determined through a technique called“Histogram Backprojection”. The low-level texture feature marks a region as coarse or fine dependingon the gray-level variance of the region.

  17. Size distributions and aerodynamic equivalence of metal chondrules and silicate chondrules in Acfer 059

    Science.gov (United States)

    Skinner, William R.; Leenhouts, James M.

    1993-01-01

    The CR2 chondrite Acfer 059 is unusual in that the original droplet shapes of metal chondrules are well preserved. We determined separate size distributions for metal chondrules and silicate chondrules; the two types are well sorted and have similar size distributions about their respective mean diameters of 0.74 mm and 1.44 mm. These mean values are aerodynamically equivalent for the contrasting densities, as shown by calculated terminal settling velocities in a model solar nebula. Aerodynamic equivalence and similarity of size distributions suggest that metal and silicate fractions experienced the same sorting process before they were accreted onto the parent body. These characteristics, together with depletion of iron in Acfer 059 and essentially all other chondrites relative to primitive CI compositions, strongly suggest that sorting in the solar nebula involved a radial aerodynamic component and that sorting and siderophile depletion in chondrites are closely related.

  18. Irritable bowel syndrome subtypes: clinical and psychological features, body mass index and comorbidities

    Directory of Open Access Journals (Sweden)

    Cristiane Kibune-Nagasako

    2016-02-01

    Full Text Available Background: Irritable bowel syndrome (IBS is classified into subtypes according to bowel habit. Objective: To investigate whether there are differences in clinical features, comorbidities, anxiety, depression and body mass index (BMI among IBS subtypes. Methods: The study group included 113 consecutive patients (mean age: 48 ± 11 years; females: 94 with the diagnosis of IBS. All of them answered a structured questionnaire for demographic and clinical data and underwent upper endoscopy. Anxiety and depression were assessed by the Hospital Anxiety and Depression scale (HAD. Results: The distribution of subtypes was: IBS-diarrhea (IBS-D, 46%; IBS-constipation (IBS-C, 32%, and mixed IBS (IBS-M, 22%. IBS overlap with gastroesophageal reflux disease (GERD, functional dyspepsia, chronic headache and fibromyalgia occurred in 65.5%, 48.7%, 40.7% and 22.1% of patients, respectively. Anxiety and/or depression were found in 81.5%. Comparisons among subgroups showed that bloating was significantly associated with IBS-M compared to IBS-D (odds ratio-OR-5.6. Straining was more likely to be reported by IBS-M (OR 15.3 and IBS-C (OR 12.0 compared to IBS-D patients, while urgency was associated with both IBS-M (OR 19.7 and IBS-D (OR 14.2 compared to IBS-C. In addition, IBS-M patients were more likely to present GERD than IBS-D (OR 6.7 and higher scores for anxiety than IBS-C patients (OR 1.2. BMI values did not differ between IBS-D and IBS-C. Conclusion: IBS-M is characterized by symptoms frequently reported by both IBS-C (straining and IBS-D (urgency, higher levels of anxiety, and high prevalence of comorbidities. These features should be considered in the clinical management of this subgroup.

  19. 新型宽速域高超声速飞行器气动特性研究%Investigation on aerodynamic performance for a novel wide-ranged hypersonic vehicle

    Institute of Scientific and Technical Information of China (English)

    李世斌; 罗世彬; 黄伟; 柳军; 金亮

    2012-01-01

    为设计一种新型宽速域滑翔飞行器,基于无粘锥导乘波设计理论,设计了Ma =4和Ma =8状态下的乘波构型,并将其进行“串联”拼接,得到一类新型宽速域乘波飞行器.采用数值模拟方法对此类飞行器的气动特性进行了研究,得到其流场特征和气动特性.结果表明,采用新型“串联”高超声速乘波飞行器,其气动性能在宽速域范围内比单马赫数条件下的乘波飞行器气动性能更优.“串联”乘波体的升阻比随马赫数的增加而变大,当Ma >8时,其气动特性变化不明显,最大升阻比接近3.2,在设计马赫数范围内,升阻比不低于2.6.升阻比随攻角的增加先变大后减小,在3°攻角时升阻比最大.在Ma =6时,基准模型-1的最大升阻比为4.714,“串联”乘波体的升阻比达到3.48.%In order to design a novel hypersonic cruise vehicle for a wide-ranged Mach numhers, two different configurations in two situations ( Ma = 4 and Ma = 8) based on the theory of waverider were designed, and then combined to achieve a novel hypersonic vehicle for a wide-ranged velocity. In this study, the commercial software Fluent was employed to numerically investigate its aerodynamic performance and flow field characteristics. The obtained results show that the aerodynamic performance of the novel combined waverider vehicle is better than that of single Mach number waverider vehicle for the wide-ranged velocity. With the increasing of Mach numbers, the lift-to-drag ratio of the novel waverider increases continually, but the gradient decreases. Its maximum value is nearly 3.2, and the value is not lower than 2. 6 in the range of design Mach number. The lift-to-drag ratio first increases, and then decreases with the increasing of the angle of attack. When the angle of attack is 3? the lift-to-drag ratio is the largest. When the Mach number is 6, the maximum value of the benchmark-1 is 4. 714, and the value of the combined waverider reaches 3.48.

  20. Numerical code for multi-component galaxies: from N-body to chemistry and magnetic fields

    CERN Document Server

    Khoperskov, S A; Khoperskov, A V; Lubimov, V N

    2015-01-01

    We present a numerical code for multi-component simulation of the galactic evolution. Our code includes the following parts: $N$-body is used to evolve dark matter, stellar dynamics and dust grains, gas dynamics is based on TVD-MUSCL scheme with the extra modules for thermal processes, star formation, magnetic fields, chemical kinetics and multi-species advection. We describe our code in brief, but we give more details for the magneto-gas dynamics. We present several tests for our code and show that our code have passed the tests with a reasonable accuracy. Our code is parallelized using the MPI library. We apply our code to study the large scale dynamics of galactic discs.

  1. QCD sum rules for quark-gluon three-body components in the B meson

    CERN Document Server

    Nishikawa, Tetsuo

    2011-01-01

    We discuss the QCD sum rule calculation of the heavy-quark effective theory parameters, $\\lambda_E$ and $\\lambda_H$, which correspond to matrix elements representing quark-gluon three-body components in the $B$-meson wavefunction. We derive the sum rules for $\\lambda_{E,H}$ calculating the new higher-order QCD corrections, i.e., the order $\\alpha_s$ radiative corrections to the Wilson coefficients associated with the dimension-5 quark-gluon mixed condensates, and the power corrections due to the dimension-6 vacuum condensates. We find that the new radiative corrections significantly improve the stability of the corresponding Borel sum rules and lead to the reduction of the values of $\\lambda_{E,H}$. We also discuss the renormalization-group improvement for the sum rules and present update on the values of $\\lambda_{E,H}$.

  2. Effects of negative energy components in two-body deuteron photodisintegratio

    CERN Document Server

    Kazakov, K Yu; Kazakov, Konstantin Yu.; Shulga, Denis V.

    2002-01-01

    Several observables in two-body deuteron photodisintegration are investigated in the framework of the Bethe-Salpeter formalism. Apart from keeping throughout Lorentz covariance, a special attention is paid to inclusion of both the positive energy and negative energy partial-wave components of the deuteron state. Using the Bethe-Salpeter equation for deuteron in the ladder approximation with one-boson exchanges as a driving force, the contribution of the negative energy states is studied for the unpolarized differential cross as well as the linear photon and tensor target asymmetries. These states are found to have an impact on the observables and, thus, should be taken into account in a complete theoretical development of the reaction in the intermediate energy regime.

  3. Avoidance of crack inducement when laser welding hot-formed car body components - a variable analysis

    Science.gov (United States)

    Larsson, Johnny K.

    The Volvo XC60 car body contains numerous parts in Ultra High Strength Steels (UHSS) in order to guarantee the structural integrity of the car in the event of a crash situation. Most of the parts are manufactured in a hot-forming process, so called presshardening, resulting in component tensile strength in the range of 1,500 MPa. As this type of material also presents fairly high carbon content (˜0.22%) it brings a challenge when it comes to welding. The Volvo XC60 car body is at the same time to a large extent assembled by laser welding technology. In early development stages of the project (Y413), it was observed that laser welding of hot-formed components presented a number of challenges due to the unique conditions offered by this welding method. The presentation will thoroughly describe the modes of procedure how to avoid crack inducement during the welding operation. A variable analysis approach was used based on the present circumstances at the production facility in the Gent plant. Crucial variables at laser welding such as gap between sheets, focal point position, welding speed and laser weld position relative to the flange edge were included in a test matrix and welding trials were carried out accordingly in the Pilot Plant in Gothenburg. The paper will discuss those welding results, the subsequent analysis and plausible theoretic explanations. From the lessons learnt in this research, the optimum laser welding parameters were then transferred to the laser welding stations in the Gent plant. There it has been proven, that also at high volume automotive manufacturing, it is possible to provide an outstanding weld quality also at such difficult pre-conditions. The presentation ends with some facts and figures and experiences from high volume series production, which also includes aspects on quality assurance.

  4. Evaluation of selected drive components for a flywheel powered commuter vehicle. Phase I. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-06-30

    The results of tests performed to evaluate the performance of selected high-speed flywheel bearings and shaft seals are reported, and work performed on the development of a high-speed composite flywheel rotor is described. The overall program objective is to develop a composite flywheel system for primary energy storage in a flywheel powered vehicle. These initial tests were intended to evaluate the performance of full-size composite rotor elements, high-speed bearings and shaft seals for that system under conditions simulating as closely as possible those anticipated in a finished vehicle. Performance of the angular contact ball bearings is reported to be satisfactory at all speeds; a simplified lubrication system is recommended for second generation hardware. Performance of the ferrofluidic shaft seals is reported to be marginal, as they failed to hold a hard vacuum at the maximum design speed. Several concepts for improved seals are offered for second generation hardware. The test objectives for the high-speed composite flywheel rotor were not achieved due to dynamic instability problems with the test hardware. Recommendations are offered for the design of second generation hardware, and a scope of activities is proposed for the second phase of this program.

  5. 40 CFR Appendix Vi to Part 86 - Vehicle and Engine Components

    Science.gov (United States)

    2010-07-01

    ...) Carburetor-idle RPM, mixture ratio. (3) Choke mechanism. (4) Fuel system filter and fuel system lines and connections. (5) Choke plate and linkage. III. Ignition Components. (1) Ignition timing and advance...

  6. Identification of the RNAs for Transcription Factor Mitf as a Component of the Balbiani Body

    Institute of Scientific and Technical Information of China (English)

    Mingyou Li; Yongming Yuan; Yunhan Hong

    2013-01-01

    Balbiani body (BB) is a large distinctive organelle aggregate uniquely present in developing oocytes of diverse animal species.BB is thought as a stage-specific structure that resembles germ plasm,the cytoplasmic organelle of germ cells.The role and function of BB have remained speculative because of a highly dynamic structure and a lack of genetic and molocular data.BB has been found to contain proteins and RNAs,none of them-except the zebrafish foxH1 RNA,is or encodes a transcription factor.Here we report in the fish medaka (Oryzias latipes) that RNAs encoding microphthalmia-associated transcription factor (Mitf) are prominent components of the BB.By fluorescence in siru hybridization on ovarian section,we revealed that the transcripts of both mitfl and mitf2 genes concentrated in the BB,in which they co-localized with the dazl RNA,a definitive BB marker highly conserved in vertebrates.Therefore,the mitfproduct may play dual roles in germ gene transcription and BB formation and/or function in this organism.Our data provide the second evidence that the RNA of a transcription factor can be a prominent component of the BB in a vertebrate.

  7. Thrust Control Features for Aerodynamic Throat for Solid Rocket Motor%固体火箭发动机气动喉部的推力调控特性

    Institute of Scientific and Technical Information of China (English)

    谢侃; 李博; 郭常超; 王宁飞

    2015-01-01

    为了研究固体火箭发动机气动喉部推力调节的一般规律,利用氮气作为介质对气动喉部喷管进行了冷流实验研究。研究了该种喷管的扼流性能,二次流嘴的面积、个数对其扼流性能的影响以及空腔容积与喷管压强调节时间的关系。掌握了气动喉部喷管的有效喉部面积随流量比变化的一般规律。结果表明,二次流与主流流量比越大,气动喉部面积越小。小的面积比具有更高的扼流性能,而当流量比大于0.4时,面积比对扼流性能无明显影响。空腔体积越小压强调节时间越短。%Adjust:In order to study the general rules of the thrust control features for aerodynamic throat for solid rocket motor, a cold-flow test research was performed on the aerodynamic nozzle throat using the nitrogen as working gas. Firstly, the choke performance of the aerodynamic throat was studied. Then, the performance of throat modification was studied considering the influence of area and number of secondary flow injectors. Final⁃ly,the relation about the volume of cavity with adjustment time of nozzle was also studied. The general law of ef⁃fective throat area along with the flow rate change was obtained through study. The results show that the larger the flow ratio of the secondary flow and main flow is, the smaller the pneumatic throat area is. The smaller area ratio has higher choke performance,and the influence of area is not obvious when the flow rate is greater than 0.4. Be⁃sides,the smaller the cavity volume is,the shorter the accommodation time of pressure is.

  8. Integrated Active and Passive Polymer Optical Components with nm to mm Features

    DEFF Research Database (Denmark)

    Christiansen, Mads Brøkner; Schøler, Mikkel; Kristensen, Anders

    2007-01-01

    We present wafer-scale fabrication of integrated active and passive polymer optics with nm to mm features. First order DFB lasers, defined in dye doped SU-8 resist are integrated with SU-8 waveguides.......We present wafer-scale fabrication of integrated active and passive polymer optics with nm to mm features. First order DFB lasers, defined in dye doped SU-8 resist are integrated with SU-8 waveguides....

  9. Computer Aided Aerodynamic Design of Missile Configuration

    OpenAIRE

    Panneerselvam, S; P. Theerthamalai; A.K. Sarkar

    1987-01-01

    Aerodynamic configurations of tactical missiles have to produce the required lateral force with minimum time lag to meet the required manoeuvability and response time. The present design which is mainly based on linearised potential flow involves (a) indentification of critical design points, (b) design of lifting components and their integration with mutual interference, (c) evaluation of aerodynamic characteristics, (d) checking its adequacy at otherpoints, (e) optimization of parameters an...

  10. Thermal Soak Analysis of Earth Entry Vehicles

    Science.gov (United States)

    Agrawal, Parul; Sepka, Steven A.; Aliaga, Jose F.; Venkatapathy, Ethiraj; Samareh, Jamshid A.

    2012-01-01

    The Multi-Mission Earth Entry Vehicle project is developing an integrated tool called Multi Mission System Analysis for Planetary Entry Descent and Landing that will provide key technology solutions including mass sizing, aerodynamics, aerothermodynamics, and thermal and structural analysis for any given sample return mission. Thermal soak analysis and temperature predictions of various components including the payload container of the entry vehicle are part of the solution that this tool will offer to mission designers. The present paper focuses on the thermal soak analysis of an entry vehicle design based on the Mars Sample Return entry vehicle geometry and discusses a technical approach to develop parametric models for thermal soak analysis that will be integrated into the tool.

  11. The study of dual energy X-ray absorptiometry on body composition components in obesity

    International Nuclear Information System (INIS)

    Objective: To study the correlation of the bone mineral density (BMD) and the body composition components of body mass index (BMI), FAT and LEAN in Chinese obesity. Methods: There were 150 cases in obesity group diagnosed by BMI, including 75 males [ median age 46 years, mean weight (89.64 ± 8.33) kg] and 75 females [median age 45 years, mean weight (77.23 ± 6.85) kg]. There were 150 persons with normal BMI in the control group, including 75 males [(median age 47 years, mean weight (62.34 ± 5.72) kg] and 75 females [ median age 45 years, mean weight (50.16 ± 5.06) kg]. The body height and weight of 300 persons in two groups were measured respectively and ,simultaneously calculated the BMI. These data and the body composition parameters measured by the dual energy X-ray absorptiometry (DEXA) in these two groups were compared and analyzed. The data obtained used two-sample t-test analysis, bi-variable correlation used Pearson linear correlation analysis and multi-variable correlation used multiple linear regression analysis. Results: FAT of arms, legs trunk and total body of male cases in obesity group was (2.90 ± 0.57), (7.48 ± 1.46), (15.67 ± 3.05), (30.92 ± 5.94) kg respectively, FAT% was (30.9 ± 5.1)%, (30.6 ± 5.8)%, (37.3 ± 4.7)%, (35.1 ± 4.4)% respectively, it was significantly higher than that in control group [FAT was (1.12 ± 0.64), (3.27 ± 1.22), (6.71 ± 3.29), (11.61 ± 5.16) kg respectively, FAT% was (15.4 ± 4.8)%, (16.5 ± 5.0)%, (21.8 ± 5.8)%, (18.6 ± 5.3)% respectively], P 2 respectively, it was significantly higher than that in control group [ LEAN was (22.89 ± 1.68), (48.89 ± 3.72) kg respectively, BMD was (0.89 ± 0.07), (1.15 ± 0.06) g/cm2 respectively], P 2 respectively, and there were no statistical significance compared with those in control group [LEAN was (5.99 ± 0.72), (16.83 ± 1.67) kg respectively, BMD was (0.90 ± 0.08), (1.29 ± 0.09) g/cm2 respectively]. FAT of arms, legs, trunk and total body of females in obesity

  12. CFD research, parallel computation and aerodynamic optimization

    Science.gov (United States)

    Ryan, James S.

    1995-01-01

    Over five years of research in Computational Fluid Dynamics and its applications are covered in this report. Using CFD as an established tool, aerodynamic optimization on parallel architectures is explored. The objective of this work is to provide better tools to vehicle designers. Submarine design requires accurate force and moment calculations in flow with thick boundary layers and large separated vortices. Low noise production is critical, so flow into the propulsor region must be predicted accurately. The High Speed Civil Transport (HSCT) has been the subject of recent work. This vehicle is to be a passenger vehicle with the capability of cutting overseas flight times by more than half. A successful design must surpass the performance of comparable planes. Fuel economy, other operational costs, environmental impact, and range must all be improved substantially. For all these reasons, improved design tools are required, and these tools must eventually integrate optimization, external aerodynamics, propulsion, structures, heat transfer and other disciplines.

  13. Aerodynamic Ground Effect in Fruitfly Sized Insect Takeoff.

    Directory of Open Access Journals (Sweden)

    Dmitry Kolomenskiy

    Full Text Available Aerodynamic ground effect in flapping-wing insect flight is of importance to comparative morphologies and of interest to the micro-air-vehicle (MAV community. Recent studies, however, show apparently contradictory results of either some significant extra lift or power savings, or zero ground effect. Here we present a numerical study of fruitfly sized insect takeoff with a specific focus on the significance of leg thrust and wing kinematics. Flapping-wing takeoff is studied using numerical modelling and high performance computing. The aerodynamic forces are calculated using a three-dimensional Navier-Stokes solver based on a pseudo-spectral method with volume penalization. It is coupled with a flight dynamics solver that accounts for the body weight, inertia and the leg thrust, while only having two degrees of freedom: the vertical and the longitudinal horizontal displacement. The natural voluntary takeoff of a fruitfly is considered as reference. The parameters of the model are then varied to explore possible effects of interaction between the flapping-wing model and the ground plane. These modified takeoffs include cases with decreased leg thrust parameter, and/or with periodic wing kinematics, constant body pitch angle. The results show that the ground effect during natural voluntary takeoff is negligible. In the modified takeoffs, when the rate of climb is slow, the difference in the aerodynamic forces due to the interaction with the ground is up to 6%. Surprisingly, depending on the kinematics, the difference is either positive or negative, in contrast to the intuition based on the helicopter theory, which suggests positive excess lift. This effect is attributed to unsteady wing-wake interactions. A similar effect is found during hovering.

  14. Aerodynamic study of sounding rocket flows using Chimera and patched multiblock meshes

    Directory of Open Access Journals (Sweden)

    João Alves de Oliveira Neto

    2011-01-01

    Full Text Available Aerodynamic flow simulations over a typical sounding rocket are presented in this paper. The work is inserted in the effort of developing computational tools necessary to simulate aerodynamic flows over configurations of interest for Instituto de Aeronáutica e Espaço of Departamento de Ciência e Tecnologia Aeroespacial. Sounding rocket configurations usually require fairly large fins and, quite frequently, have more than one set of fins. In order to be able to handle such configurations, the present paper presents a novel methodology which combines both Chimera and patched multiblock grids in the discretization of the computational domain. The flows of interest are modeled using the 3-D Euler equations and the work describes the details of discretization procedure, which uses a finite difference approach for structure, body-conforming, multiblock grids. The method is used to calculate the aerodynamics of a sounding rocket vehicle. The results indicate that the present approach can be a powerful aerodynamic analysis and design tool.

  15. CFD Simulations in Support of Shuttle Orbiter Contingency Abort Aerodynamic Database Enhancement

    Science.gov (United States)

    Papadopoulos, Periklis E.; Prabhu, Dinesh; Wright, Michael; Davies, Carol; McDaniel, Ryan; Venkatapathy, E.; Wercinski, Paul; Gomez, R. J.

    2001-01-01

    Modern Computational Fluid Dynamics (CFD) techniques were used to compute aerodynamic forces and moments of the Space Shuttle Orbiter in specific portions of contingency abort trajectory space. The trajectory space covers a Mach number range of 3.5-15, an angle-of-attack range of 20deg-60deg, an altitude range of 100-190 kft, and several different settings of the control surfaces (elevons, body flap, and speed brake). Presented here are details of the methodology and comparisons of computed aerodynamic coefficients against the values in the current Orbiter Operational Aerodynamic Data Book (OADB). While approximately 40 cases have been computed, only a sampling of the results is provided here. The computed results, in general, are in good agreement with the OADB data (i.e., within the uncertainty bands) for almost all the cases. However, in a limited number of high angle-of-attack cases (at Mach 15), there are significant differences between the computed results, especially the vehicle pitching moment, and the OADB data. A preliminary analysis of the data from the CFD simulations at Mach 15 shows that these differences can be attributed to real-gas/Mach number effects. The aerodynamic coefficients and detailed surface pressure distributions of the present simulations are being used by the Shuttle Program in the evaluation of the capabilities of the Orbiter in contingency abort scenarios.

  16. 75 FR 7370 - Federal Motor Vehicle Safety Standards; Door Locks and Door Retention Components

    Science.gov (United States)

    2010-02-19

    ... Federal Specifications for the Star-of-Life Ambulance.\\13\\ Section 3.10.9 of the GSA standard states... Safety Standard (FMVSS) No. 206, Door Locks and Door Retention Components (49 CFR 571.206) (72 FR 5385.... NHTSA's Part I Response To accommodate manufacturers' design and production cycles while allowing...

  17. EXTRACTING ROAD FEATURES FROM AERIAL VIDEOS OF SMALL UNMANNED AERIAL VEHICLES

    Directory of Open Access Journals (Sweden)

    D. Rajamohan

    2013-09-01

    Full Text Available With major aerospace companies showing interest in certifying UAV systems for civilian airspace, their use in commercial remote sensing applications like traffic monitoring, map refinement, agricultural data collection, etc., are on the rise. But ambitious requirements like real-time geo-referencing of data, support for multiple sensor angle-of-views, smaller UAV size and cheaper investment cost have lead to challenges in platform stability, sensor noise reduction and increased onboard processing. Especially in small UAVs the geo-referencing of data collected is only as good as the quality of their localization sensors. This drives a need for developing methods that pickup spatial features from the captured video/image and aid in geo-referencing. This paper presents one such method to identify road segments and intersections based on traffic flow and compares well with the accuracy of manual observation. Two test video datasets, one each from moving and stationary platforms were used. The results obtained show a promising average percentage difference of 7.01 % and 2.48 % for the road segment extraction process using moving and stationary platform respectively. For the intersection identification process, the moving platform shows an accuracy of 75 % where as the stationary platform data reaches an accuracy of 100 %.

  18. The 6 $\\mu$m Feature as A Tracer of Aliphatic Components of Interstellar Carbonaceous Grains

    CERN Document Server

    Hsia, Chih-Hao; Zhang, Yong; Kwok, Sun

    2016-01-01

    An unidentified infrared emission (UIE) feature at 6.0 $\\mu$m is detected in a number of astronomical sources showing the UIE bands. In contrast to the previous suggestion that this band is due to C=O vibrational modes, we suggest that the 6.0 $\\mu$m feature arises from olefinic double-bond functional groups. These groups are likely to be attached to aromatic rings which are responsible for the major UIE bands. The possibility that the formation of these functional groups is related to the hydrogenation process is discussed.

  19. Wing Flexion and Aerodynamics Performance of Insect Free Flights

    Science.gov (United States)

    Dong, Haibo; Liang, Zongxian; Ren, Yan

    2010-11-01

    Wing flexion in flapping flight is a hallmark of insect flight. It is widely thought that wing flexibility and wing deformation would potentially provide new aerodynamic mechanisms of aerodynamic force productions over completely rigid wings. However, there are lack of literatures on studying fluid dynamics of freely flying insects due to the presence of complex shaped moving boundaries in the flow domain. In this work, a computational study of freely flying insects is being conducted. High resolution, high speed videos of freely flying dragonflies and damselflies is obtained and used as a basis for developing high fidelity geometrical models of the dragonfly body and wings. 3D surface reconstruction technologies are used to obtain wing topologies and kinematics. The wing motions are highly complex and a number of different strategies including singular vector decomposition of the wing kinematics are used to examine the various kinematical features and their impact on the wing performance. Simulations are carried out to examine the aerodynamic performance of all four wings and understand the wake structures of such wings.

  20. Successful Bullying Prevention Programs: Influence of Research Design, Implementation Features, and Program Components

    Directory of Open Access Journals (Sweden)

    Bryanna Hahn Fox

    2012-12-01

    Full Text Available Bullying prevention programs have been shown to be generally effective in reducing bullying and victimization. However, the effects are relatively small in randomized experiments and greater in quasi-experimental and age-cohort designs. Programs that are more intensive and of longer duration (for both children and teachers are more effective, as are programs containing more components. Several program components are associated with large effect sizes, including parent training or meetings and teacher training. These results should inform the design and evaluation of anti-bullying programs in the future, and a system ofaccreditation of effective programs.

  1. Minimum-fuel aerodynamic orbital plane change maneuvers. [for Space Shuttle Orbiters

    Science.gov (United States)

    Joosten, B. K.; Pierson, B. L.

    1981-01-01

    Several minimum-fuel, aerodynamically controlled, orbital plane change problems are formulated and solved as optimal control problems. A gradient projection algorithm is used to iteratively modify both the control functions, angle of attack and bank angle, and two control parameters to obtain the optimal trajectory. The atmospheric flight profile is combined with two Keplerian (two-body vacuum flight) arcs so that a complete orbit-to-orbit analysis results. The vehicle used in this investigation is the Space Transportation System Shuttle Orbiter. The effects of heat load constraint level and plane change angle are analysed.

  2. Application of systems engineering techniques to component design - Capturing functionality and linking part 'critical to quality' features to requirements

    International Nuclear Information System (INIS)

    A systems engineering approach - focusing upon functionality - has predominantly been applied in industry to the design of complex systems with many functional interactions, inputs and outputs, eg the design of a decay heat removal system. This paper presents how systems engineering techniques can be applied to component design, i.e. treating the component as a system in its own right, and using functionality as the 'bridge' between the customer requirements and accepted performance. A pressure relief valve is used as an example to present the techniques of: Functional Modelling to establish the functional requirements and Functional Failure Modes and Effects Analysis to establish any emergent functionality to reduce the risk of adverse behaviour. A key aspect of component design is capturing the design intent and establishing the 'Critical to Quality 'features that can critically affect quality and performance. This paper details 'Quality Function Deployment' being applied to a component to capture such features and to establish a clear link to the overarching performance requirements. This approach is particularly useful in ensuring continuity of design understanding throughout the component life cycle, assessing the effects of any proposed changes to the design and the effects of changes in system or customer requirements, or for using the design in a different application. (authors)

  3. Counterregulation of insulin by leptin as key component of autonomic regulation of body weight

    Institute of Scientific and Technical Information of China (English)

    Katarina; T; Borer

    2014-01-01

    A re-examination of the mechanism controlling eating, locomotion, and metabolism prompts formulation of a new explanatory model containing five features: a coordinating joint role of the(1) autonomic nervous system(ANS);(2) the suprachiasmatic(SCN) master clock in counterbalancing parasympathetic digestive and absorptive functions and feeding with sympathetic locomotor and thermogenic energy expenditure within a circadian framework;(3) interaction of the ANS/SCN command with brain substrates of reward encompassing dopaminergic projections to ventral striatum and limbic and cortical forebrain. These drive the nonhomeostatic feeding and locomotor motivated behaviors in interaction with circulating ghrelin and lateral hypothalamic neurons signaling through melanin concentrating hormone and orexin-hypocretin peptides;(4) counterregulation of insulin by leptin of both gastric and adipose tissue origin through: potentiation by leptin of cholecystokinin-mediated satiation, inhibition of insulin secretion, suppression of insulin lipogenesis by leptin lipolysis, and modulation of peripheral tissue and brain sensitivity to insulin action. Thus weight-loss induced hypoleptimia raises insulin sensitivity and promotes its parasympathetic anabolic actions while obesity-induced hyperleptinemia supresses insulin lipogenic action; and(5) inhibition by leptin of bone mineral accrual suggesting that leptin may contribute to the maintenance of stability of skeletal, lean-body, as well as adipose tissue masses.

  4. KEY TECHNIQUES OF MULTI-BODY MODELING OF OCCUPANT RESTRAINT SYSTEM OF VEHICLE SIDE IMPACT

    Institute of Scientific and Technical Information of China (English)

    ZHANG Junyuan; ZHANG Min; DING Rufang; QIU Shaobo; ZHANG Yu; LI Hongjian

    2006-01-01

    Based on multi-body dynamics, the simulation models of auto-side structures and occupant's dynamic responses are set up, using the occupant injury simulation software MADYMO3D. These models include auto-body structure, impact barrier, seat and dummy. Definitions of multi-body and joints and dynamics properties of joints based on FE combination models, of model setup are introduced. Kelvin element of MADYMO is introduced to show the force action between non-adjoining rigid bodies, too. Then all examples of the methods mentioned are given. By the comparison of simulation and real test, the contract curves between simulation and real test for main structures and biology mechanics properties of dummy are obtained. The result shows the accuracy and validity of the models.

  5. Dynamics of the component of body composition in athletes playing sports with damage to the medial meniscus of the knee

    OpenAIRE

    Moh'd Khalil Moh'd Abdel Kader.

    2012-01-01

    The question of the influence of the developed program of physical rehabilitation with the use of modern means and methods of recovery on the performance component of body composition in athletes playing sports after arthroscopic stapling the medial meniscus was considered. The analysis and synthesis of scientific and methodological data on the determination of body composition analysis techniques using bioelectrical resistance was shown. Found that long-term immobilization that accompanies t...

  6. Comparative study of contents of several bioactive components in fruiting bodies and mycelia of culinary-medicinal mushrooms.

    Science.gov (United States)

    Lo, Yu-Chang; Lin, Shin-Yi; Ulziijargal, Enkhjargal; Chen, Shin-Yu; Chien, Rao-Chi; Tzou, Yi-Jing; Mau, Jeng-Leun

    2012-01-01

    Mushrooms have been consumed for thousands of years, and several bioactive components were found therein, including lovastatin, γ-aminobutyric acid (GABA) and ergothioneine. The study reported herein was to analyze these three bioactive components in 15 fruiting bodies and 9 mycelia of 19 species of mushrooms from genera Agaricus, Agrocybe, Auricularia, Boletus, Ganoderma, Hypsizygus, Inonotus, Lentinus, Morchella, Pleurotus, Tremella, Termitomyces, and Volvariella. The results show that Hypsizygus marmoreus contained the highest amount of lovastatin (628.05 mg/kg) in fruiting bodies and Morchella esculenta contained the highest amount (1438.42 mg/ kg) in mycelia. Agaricus brasiliensis contained the highest amount of GABA (1844.85 mg/kg) in fruiting bodies, and mycelia of Boletus edulis, Pleurotus citrinopileatus, and Termitomyces albuminosus contained extraordinarily higher amounts (1274.03, 1631.67, and 2560.00 mg/kg, respectively). Volvariella volvacea contained the highest amount of ergothioneine (537.27 mg/kg) in fruiting bodies and mycelia; Boletus edulis, Pleurotus ferulae, and P. salmoneostramineus contained relatively higher amount of ergothioneine too (258.03, 250.23, and 222.08 mg/kg, respectively). However, none of these components was detected in fruiting bodies of Inonotus obliquus. In conclusion, these three bioactive components were commonly found in most mushrooms, and these results might be related to their beneficial effects. PMID:23510173

  7. Relationship of Heath and Carter's Second Component to Lean Body Mass and Height in College Women

    Science.gov (United States)

    Slaughter, M. H.; And Others

    1977-01-01

    The Heath and Carter approach to determining somatotypes is less accurate than is regression analysis, mainly because of the lack of association between skeletal widths and lean body mass as measured by body density and whole-body fat percentage, holding constant muscle circumference. (Author)

  8. ENERGY PECULIAR FEATURES PERTAINING TO NANO- TECHNOLOGY OF COATING DEPOSITION USING MIXED MATRICES FOR AUTOMOTIVE COMPONENTS

    Directory of Open Access Journals (Sweden)

    V. Ivashko

    2012-01-01

    Full Text Available A systematic analysis of factors that influence on the processes of  protective coating formation based on mixed matrices has been presented in the paper. The paper demonstrates a significant role of energy parameters of modifier drop-phase dispersed particles formed in the process of pneumatic spraying  and surface layer of a metal substrate on the mechanisms pertaining to formation of coating structure with optimal characteristics. Compositions of anticorrosive and tribological coatings for application in the designs of higher resource automotive components  have been proposed in the paper.

  9. Study on aerodynamic performances of a vehicle for the catenary maintenance under crosswinds%强侧风条件下接触网检修作业车气动性能研究

    Institute of Scientific and Technical Information of China (English)

    刘金明; 刘堂红; 苏新超

    2015-01-01

    Since the lack of researches on the operation safety for catenary maintenance vehicle under strong cross wind,the aerodynamic performance of catenary maintenance vehicle under different wind -break facilities, different railway conditions,and different cross wind were performed using three dimensional incompressible Navier -Stokes equation and k -εturbulence model.The results show that,with an increase in embankment height in the condition of wind -break wall,the vehicle overturning moment increases when the yaw angle is small,and decreases when the yaw angle is larger.The inflection point variced from 45°to 60°,Where specific numerical value wasrelated to the wind wall type.Where there is none of the wind wall,with an increase in em-bankment height,the vehicle overturning increases when β≤60°and decreases when β>60°.When car work platform rises and rotates from -120°to 120°,the overturning moment would reach its maximum at 30°and minimum at -90°.%针对接触网检修作业车自轮运转特种设备在大风天气下运行及作业安全标准研究的缺乏,采用三维、不可压 N -S方程和 k -ε双方程湍流模型,计算不同防风设施、不同路况和不同环境风风速风向条件对接触网作业车气动性能的影响规律。研究结果表明:有挡风墙下,侧滑角较小时,随着路堤高度的增加,车辆倾覆力矩增大;侧滑角较大时,随着路堤高度的增加,车辆倾覆力矩减小;其拐点在45°~60°左右,具体数值与挡风墙类型有关。无挡风墙下,当侧滑角β≤60°时,车辆气动倾覆力矩随着路堤高度的增高而增大;当侧滑角β>60°时,车辆气动倾覆力矩随路堤高度的增高变化不大。接触网作业车工作平台升起、在-120°~120°转动时,30°左右时整车的倾覆力矩最大,-90°左右时最小。

  10. Sensitivity and Specificity of Body Mass Index as a Definition of the Obesity Component of Metabolic Syndrome

    OpenAIRE

    M. Chakraborty, Bandana; Chakraborty, Ranajit

    2007-01-01

    Metabolic syndrome (MS) is a combination of risk factors that are associated with several chronic diseases. Its components (obesity, dyslipidemia, carbohydrate intolerance, hypertension, microalbumineria) are diverse, whose thresholds vary in different definitions of MS. For example, a World Health Organization (WHO) panel defined the obesity component of MS based on waist-hip ratio, or body mass index (BMI), while the National Cholesterol Education Program (NCEP) defined the obes...

  11. Computation of dragonfly aerodynamics

    Science.gov (United States)

    Gustafson, Karl; Leben, Robert

    1991-04-01

    Dragonflies are seen to hover and dart, seemingly at will and in remarkably nimble fashion, with great bursts of speed and effectively discontinuous changes of direction. In their short lives, their gossamer flight provides us with glimpses of an aerodynamics of almost extraterrestrial quality. Here we present the first computer simulations of such aerodynamics.

  12. The design features of the body of the portable electrocardiograph «ECG-EXPRESS»

    Science.gov (United States)

    Seryakov, V.; Khmelevsky, Yu; Mamontov, G.

    2015-10-01

    The sequence of the industrial product shaping is specified, the main modeling characteristics of the configuration and some of its parts are designated subject to the electrocardiograph design and the technologies used for the production of its body.

  13. Imaging Features for the Prediction of Extensive Intraductal Components in Invasive Cancer in Addition to the Histopathologic Grades

    Energy Technology Data Exchange (ETDEWEB)

    Han, Hye Yoen; Kim, Keum Won; Park, Yong Sung; Cho, Yong Jun; Hwang, Cheol Mog; Kim, Hyun Jin; Sul, Hae Jung; Yoon, Dae Sung [Konyang University, College of Medicine, Nonsan (Korea, Republic of); Kim, Gyu Soon [Eulji University, College of Medicine, Daejeon (Korea, Republic of)

    2009-12-15

    To evaluate the usefulness of US and mammography in detecting extensive intraductal component (EIC) in invasive cancer and correlating the results with the histopathologic grade. We retrospectively reviewed the mammographic and sonographic features of 125 invasive breast cancers, classified as 'invasive cancer with EIC' (n=57) and 'invasive cancer without EIC' (n=68). The mammographic features are classified as microcalcifications only, microcalcifications beyond the soft tissue density, soft tissue density without microcalcification, and sonographic features classified according to ten sonographic suspicious features for malignancy by Stavros. We calculated sensitivities, specificities, positive predictive value, negative predictive value, and accuracy to correlate them with histologic grade. Microcalcifications on mammography, calcification, duct extension, and a branching pattern on sonography were found to be statistically significant predictors of EIC. Also, a thick echogenic halo, angular margin, microlobuation, taller than wide feature on sonography, and soft tissue shadow without microcalcification on mammography showed a decreased risk of EIC. In addition, the presence of a branching pattern is an indicator of high histologic grade (p<0.05). Microcalcification on mammography, calcification, duct extension, and branching pattern on sonography are an indicator of the presence of EIC in invasive cancer. In addition, when a branching pattern is present, the tumor tends to have a high histologic grade.

  14. Sand transverse dune aerodynamics: 3D Coherent Flow Structures from a computational study

    CERN Document Server

    Bruno, Luca

    2015-01-01

    The engineering interest about dune fields is dictated by the their interaction with a number of human infrastructures in arid environments. The aerodynamic behaviour of sand dunes in atmospheric boundary layer belongs to the class of bluff bodies. Because of their simple geometry and their frequent occurrence in desert area, transverse sand dunes are usually adopted in literature as a benchmark to investigate dune aerodynamics by means of both computational or experimental approach, usually in nominally 2D setups. The writers suspect the flow in the wake is characterised by 3D features and affected by wind tunnel setup - e.g. blockage effect, duct side wall boundary layer, incoming velocity profile - when experimental studies are carried out. The present study aims at evaluating the 3D flow features of an idealised transverse dune under different setup conditions by means of computational simulations and to compare the obtained results with experimental measurements.

  15. The Component Packaging Problem: A Vehicle for the Development of Multidisciplinary Design and Analysis Methodologies

    Science.gov (United States)

    Fadel, Georges; Bridgewood, Michael; Figliola, Richard; Greenstein, Joel; Kostreva, Michael; Nowaczyk, Ronald; Stevenson, Steve

    1999-01-01

    This report summarizes academic research which has resulted in an increased appreciation for multidisciplinary efforts among our students, colleagues and administrators. It has also generated a number of research ideas that emerged from the interaction between disciplines. Overall, 17 undergraduate students and 16 graduate students benefited directly from the NASA grant: an additional 11 graduate students were impacted and participated without financial support from NASA. The work resulted in 16 theses (with 7 to be completed in the near future), 67 papers or reports mostly published in 8 journals and/or presented at various conferences (a total of 83 papers, presentations and reports published based on NASA inspired or supported work). In addition, the faculty and students presented related work at many meetings, and continuing work has been proposed to NSF, the Army, Industry and other state and federal institutions to continue efforts in the direction of multidisciplinary and recently multi-objective design and analysis. The specific problem addressed is component packing which was solved as a multi-objective problem using iterative genetic algorithms and decomposition. Further testing and refinement of the methodology developed is presently under investigation. Teaming issues research and classes resulted in the publication of a web site, (http://design.eng.clemson.edu/psych4991) which provides pointers and techniques to interested parties. Specific advantages of using iterative genetic algorithms, hurdles faced and resolved, and institutional difficulties associated with multi-discipline teaming are described in some detail.

  16. Aerodynamic Parameter Identification of a Venus Lander

    Science.gov (United States)

    Sykes, Robert A.

    An analysis was conducted to identify the parameters of an aerodynamic model for a Venus lander based on experimental free-flight data. The experimental free-flight data were collected in the NASA Langley 20-ft Vertical Spin Tunnel with a 25-percent Froude-scaled model. The experimental data were classified based on the wind tunnel run type: runs where the lander model was unperturbed over the course of the run, and runs were the model was perturbed (principally in pitch, yaw, and roll) by the wind tunnel operator. The perturbations allow for data to be obtained at higher wind angles and rotation rates than those available from the unperturbed data. The model properties and equations of motion were used to determine experimental values for the aerodynamic coefficients. An aerodynamic model was selected using a priori knowledge of axisymmetric blunt entry vehicles. The least squares method was used to estimate the aerodynamic parameters. Three sets of results were obtained from the following data sets: perturbed, unperturbed, and the combination of both. The combined data set was selected for the final set of aerodynamic parameters based on the quality of the results. The identified aerodynamic parameters are consistent with that of the static wind tunnel data. Reconstructions, of experimental data not used in the parameter identification analyses, achieved similar residuals as those with data used to identify the parameters. Simulations of the experimental data, using the identified parameters, indicate that the aerodynamic model used is incapable of replicating the limit cycle oscillations with stochastic peak amplitudes observed during the test.

  17. Principal Component Analysis-Linear Discriminant Analysis Feature Extractor for Pattern Recognition

    CERN Document Server

    Khan, Aamir

    2012-01-01

    Robustness of embedded biometric systems is of prime importance with the emergence of fourth generation communication devices and advancement in security systems This paper presents the realization of such technologies which demands reliable and error-free biometric identity verification systems. High dimensional patterns are not permitted due to eigen-decomposition in high dimensional image space and degeneration of scattering matrices in small size sample. Generalization, dimensionality reduction and maximizing the margins are controlled by minimizing weight vectors. Results show good pattern by multimodal biometric system proposed in this paper. This paper is aimed at investigating a biometric identity system using Principal Component Analysis and Lindear Discriminant Analysis with K-Nearest Neighbor and implementing such system in real-time using SignalWAVE.

  18. Principal Component Analysis-Linear Discriminant Analysis Feature Extractor for Pattern Recognition

    Directory of Open Access Journals (Sweden)

    Aamir Khan

    2011-11-01

    Full Text Available Robustness of embedded biometric systems is of prime importance with the emergence of fourth generation communication devices and advancement in security systems This paper presents the realization of such technologies which demands reliable and error-free biometric identity verification systems. High dimensional patterns are not permitted due to eigen-decomposition in high dimensional image space and degeneration of scattering matrices in small size sample. Generalization, dimensionality reduction and maximizing the margins are controlled by minimizing weight vectors. Results show good pattern by multimodal biometric system proposed in this paper. This paper is aimed at investigating a biometric identity system using Principal Component Analysis and Lindear Discriminant Analysis with K-Nearest Neighbor and implementing such system in real-time using SignalWAVE.

  19. Potential for monitoring soil erosion features and soil erosion modeling components from remotely sensed data

    Science.gov (United States)

    Langran, K. J.

    1983-01-01

    Accurate estimates of soil erosion and its effects on soil productivity are essential in agricultural decision making and planning from the field scale to the national level. Erosion models have been primarily developed for designing erosion control systems, predicting sediment yield for reservoir design, predicting sediment transport, and simulating water quality. New models proposed are more comprehensive in that the necessary components (hydrology, erosion-sedimentation, nutrient cycling, tillage, etc.) are linked in a model appropriate for studying the erosion-productivity problem. Recent developments in remote sensing systems, such as Landsat Thematic Mapper, Shuttle Imaging Radar (SIR-B), etc., can contribute significantly to the future development and operational use of these models.

  20. Exploring the Aerodynamic Drag of a Moving Cyclist

    Science.gov (United States)

    Theilmann, Florian; Reinhard, Christopher

    2016-01-01

    Although the physics of cycling itself is a complex mixture of aerodynamics, physiology, mechanics, and heuristics, using cycling as a context for teaching physics has a tradition of certainly more than 30 years. Here, a possible feature is the discussion of the noticeable resistant forces such as aerodynamic drag and the associated power…

  1. Aerodynamic and Aeroacoustic Wind Tunnel Testing of the Orion Spacecraft

    Science.gov (United States)

    Ross, James C.

    2011-01-01

    The Orion aerodynamic testing team has completed more than 40 tests as part of developing the aerodynamic and loads databases for the vehicle. These databases are key to achieving good mechanical design for the vehicle and to ensure controllable flight during all potential atmospheric phases of a mission, including launch aborts. A wide variety of wind tunnels have been used by the team to document not only the aerodynamics but the aeroacoustic environment that the Orion might experience both during nominal ascents and launch aborts. During potential abort scenarios the effects of the various rocket motor plumes on the vehicle must be accurately understood. The Abort Motor (AM) is a high-thrust, short duration motor that rapidly separates Orion from its launch vehicle. The Attitude Control Motor (ACM), located in the nose of the Orion Launch Abort Vehicle, is used for control during a potential abort. The 8 plumes from the ACM interact in a nonlinear manner with the four AM plumes which required a carefully controlled test to define the interactions and their effect on the control authority provided by the ACM. Techniques for measuring dynamic stability and for simulating rocket plume aerodynamics and acoustics were improved or developed in the course of building the aerodynamic and loads databases for Orion.

  2. Dietary fibre components and pectin chemical features of peels during ripening in banana and plantain varieties.

    Science.gov (United States)

    Happi Emaga, Thomas; Robert, Christelle; Ronkart, Sébastien N; Wathelet, Bernard; Paquot, Michel

    2008-07-01

    The effects of the ripeness stage of banana (Musa AAA) and plantain (Musa AAB) peels on neutral detergent fibre, acid detergent fibre, cellulose, hemicelluloses, lignin, pectin contents, and pectin chemical features were studied. Plantain peels contained a higher amount of lignin but had a lower hemicellulose content than banana peels. A sequential extraction of pectins showed that acid extraction was the most efficient to isolate banana peel pectins, whereas an ammonium oxalate extraction was more appropriate for plantain peels. In all the stages of maturation, the pectin content in banana peels was higher compared to plantain peels. Moreover, the galacturonic acid and methoxy group contents in banana peels were higher than in plantain peels. The average molecular weights of the extracted pectins were in the range of 132.6-573.8 kDa and were not dependant on peel variety, while the stage of maturation did not affect the dietary fibre yields and the composition in pectic polysaccharides in a consistent manner. This study has showed that banana peels are a potential source of dietary fibres and pectins. PMID:17931857

  3. The effect of swimming training on body composition and motoric features in adult sedentary young men

    Directory of Open Access Journals (Sweden)

    Hasan Aykut Aysan

    2011-03-01

    Full Text Available The aim of this study was to investigate theeffect of 8 week of swimming training program on motoricfeatures, resting heart rate, blood pressure, andbody composition in young sedentary men.Materials and methods: Forty volunteers aged between20 and 29 years participated in the research. The participants’body weight, percentage of body fat, body massindex, flexibility, push-up, shuttle, horizontal-verticaljump and 20-meter sprint were measured and comparedbefore and after the 8 weeks of swimming training program.Results: At the end of the study, study groups’ measurementswere compared. Significant decreases wereobserved on parameters of percentage of body fat and20 m sprint run between pre-post test (p0.05. Significant increaseswere observed on parameters of push-up, verticaljump (p0.05.Conclusion: Eight weeks swimming training seems toreduce percentage of body fat. It has been observed that8 weeks swimming training increased values of push-up,shuttle and vertical jump. On the other hand, no changewas observed in values of flexibility and horizontal jump.J Clin Exp Invest 2010; 2(1: 69-73

  4. Modal identities for elastic bodies, with application to vehicle dynamics and control

    Science.gov (United States)

    Hughes, P. C.

    1980-01-01

    It is a standard procedure to analyze a flexible vehicle in terms of its vibration frequencies and mode shapes. However, the entire mode shape is not needed per se, but two integrals of the mode shape, pi and hi, which correspond to the momentum and angular momentum in Mode i. Together with the natural frequencies omega-i, these modal parameters satisfy several important identities, 25 of which are derived in this paper. Expansions in terms of both constrained and unconstrained modes are considered. A simple illustrative example is included. The paper concludes with some remarks on the theoretical and practical utility of these results, and several potential extensions to the theory are suggested.

  5. Effects of Dietary Male and Female Ferula Eleaochytris Powder on Growth Performance and Body Components of Broiler Chicks

    Directory of Open Access Journals (Sweden)

    Metin Duru

    2015-03-01

    Full Text Available The purpose of this study was to investigate the effects of dietary addition of male and female Ferula eleaochytris powder (FEP on growth performance and body components of broilers (Ross-308. Treatment groups were allocated to 5 dietary in which 0 (control, 5 g and 10 g male FEP, 5 g and 10 g female FEP doses per kg commercial broiler diet. In total, 80 male broiler chicks (1-d old in which 16 animals in each group were used in study. Body weight gain and feed intake were monitored weekly for 6 weeks. Forty two days old broiler chicks were slaughtered to determine the possible changes in body components. The results of the study indicated that FEP had no effect on any parameters. However; the weight of the control group gave higher values than 5 g male Ferula group. In conclusion the measured parameters had no effect between all groups.

  6. Specific Features of Functioning of Exchanges as Components of the Market Infrastructure

    Directory of Open Access Journals (Sweden)

    Yasenetskyi Volodymyr S.

    2014-01-01

    Full Text Available The goal of the article lies in generalisation of functions of modern exchanges, analysis of specific features of the organisational and legal status of commodity and stock exchanges in Ukraine, detection of problems in exchange trade development and development of a set of measures for their solution. The article considers an exchange as a poly-functional institute that performs specific functions: organisation of regular trade with financial and tangible assets in the prescribed place and in accordance with the established rules; development of rules of exchange trade and their observance by all participants of the trade; guarantee of execution of the concluded transactions; detection, fixation and monitoring of current prices on exchange commodities. Comparison of the organisational and legal statuses of commodity and stock exchanges in Ukraine showed that stock exchanges have higher entrance barriers (organisational and legal form, minimal size of the authorised capital, order of use of profit, specific registration procedures and licensing of activity. It was found in the result of the study that underdevelopment of the exchange segment of trade in Ukraine, on the one hand, is caused by availability of system problems in the national economic system and, on the other hand, is an inhibitory factor of economic development. Measures on improvement of the state regulation of the exchange trade includes putting in order the organisational and legal status of exchanges, overcoming the existing fragmentariness of trade areas, development of mechanisms of guarantee of execution of the concluded exchange transactions and stimulation of exchanges to introduce modern electronic trade systems. The prospect of further studies in this direction is development of approaches to assessment of effectiveness and efficiency of exchange trade in Ukraine.

  7. Mean-square radii of two-component three-body systems in two spatial dimensions

    Science.gov (United States)

    Sandoval, J. H.; Bellotti, F. F.; Jensen, A. S.; Yamashita, M. T.

    2016-08-01

    We calculate root-mean-square radii for a three-body system confined to two spatial dimensions and consisting of two identical bosons (A ) and one distinguishable particle (B ). We use zero-range two-body interactions between each of the pairs, and focus thereby directly on universal properties. We solve the Faddeev equations in momentum space and express the mean-square radii in terms of first-order derivatives of the Fourier transforms of densities. The strengths of the interactions are adjusted for each set of masses to produce equal two-body bound-state energies between different pairs. The mass ratio, A =mB/mA , between particles B and A are varied from 0.01 to 100, providing a number of bound states decreasing from 8 to 2. Energies and mean-square radii of these states are analyzed for small A by use of the Born-Oppenheimer potential between the two heavy A particles. For large A the radii of the two bound states are consistent with a slightly asymmetric three-body structure. When A approaches thresholds for binding of the three-body excited states, the corresponding mean-square radii diverge inversely proportional to the deviation of the three-body energy from the two-body thresholds. The structures at these three-body thresholds correspond to bound A B dimers and one loosely bound A particle.

  8. Feature constrained compressed sensing CT image reconstruction from incomplete data via robust principal component analysis of the database

    International Nuclear Information System (INIS)

    In computed tomography (CT), incomplete data problems such as limited angle projections often cause artifacts in the reconstruction results. Additional prior knowledge of the image has shown the potential for better results, such as a prior image constrained compressed sensing algorithm. While a pre-full-scan of the same patient is not always available, massive well-reconstructed images of different patients can be easily obtained from clinical multi-slice helical CTs. In this paper, a feature constrained compressed sensing (FCCS) image reconstruction algorithm was proposed to improve the image quality by using the prior knowledge extracted from the clinical database. The database consists of instances which are similar to the target image but not necessarily the same. Robust principal component analysis is employed to retrieve features of the training images to sparsify the target image. The features form a low-dimensional linear space and a constraint on the distance between the image and the space is used. A bi-criterion convex program which combines the feature constraint and total variation constraint is proposed for the reconstruction procedure and a flexible method is adopted for a good solution. Numerical simulations on both the phantom and real clinical patient images were taken to validate our algorithm. Promising results are shown for limited angle problems. (paper)

  9. Prevalence of Body Dysmorphic Disorder Symptoms and Associated Clinical Features among Australian University Students

    Science.gov (United States)

    Bartsch, Dianna

    2007-01-01

    The current study addressed the frequency of body dysmorphic disorder (BDD) symptoms among university students and investigated the predictors of dysmorphic concern. Six hundred and nineteen Australian university students completed measures assessing BDD, dysmorphic concern, self-esteem, depression, life satisfaction, self-oriented and socially…

  10. Distributed Propulsion featuring Boundary Layer Ingestion Engines for the Blended Wing Body Subsonic Transport

    NARCIS (Netherlands)

    Kok, H.J.M.; Voskuijl, M.; Van Tooren, M.J.L.

    2010-01-01

    The blended wing body aircraft is one of the promising contenders for the next generation large transport aircraft. This aircraft is particularly suitable for the use of boundary layer ingestion engines. Results published in literature suggest that it might be beneficial to have a large number of th

  11. Low cost, small form factor, and integration as the key features for the optical component industry takeoff

    Science.gov (United States)

    Schiattone, Francesco; Bonino, Stefano; Gobbi, Luigi; Groppi, Angelamaria; Marazzi, Marco; Musio, Maurizio

    2003-04-01

    In the past the optical component market has been mainly driven by performances. Today, as the number of competitors has drastically increased, the system integrators have a wide range of possible suppliers and solutions giving them the possibility to be more focused on cost and also on footprint reduction. So, if performances are still essential, low cost and Small Form Factor issues are becoming more and more crucial in selecting components. Another evolution in the market is the current request of the optical system companies to simplify the supply chain in order to reduce the assembling and testing steps at system level. This corresponds to a growing demand in providing subassemblies, modules or hybrid integrated components: that means also Integration will be an issue in which all the optical component companies will compete to gain market shares. As we can see looking several examples offered by electronic market, to combine low cost and SFF is a very challenging task but Integration can help in achieving both features. In this work we present how these issues could be approached giving examples of some advanced solutions applied to LiNbO3 modulators. In particular we describe the progress made on automation, new materials and low cost fabrication methods for the parts. We also introduce an approach in integrating optical and electrical functionality on LiNbO3 modulators including RF driver, bias control loop, attenuator and photodiode integrated in a single device.

  12. Analysis of Effects of Mini-Vehicle Components And Parts Design to Engine Electronic Control Calibration%微型汽车零部件设计对整车电控标定影响的分析

    Institute of Scientific and Technical Information of China (English)

    武斐; 陈国栋; 王昊; 王桂洋; 袁忠庄

    2012-01-01

    结合自主标定的某微型汽车产品项目,阐述了其油泵总成、发电机、触媒、真空助力器、传动系等主要零部件的结构特点.研究了这些关键零部件对整车冷起动标定、高温热起动标定、排放标定、怠速稳定性标定、OBD标定等的影响,并通过实例总结了微型汽车整车标定的特点.%Based on one mini-vehicle project which is calibrated independently by FAW, the structural features of the mini-vehicle components and parts, including fuel pump assembly, generator, catalytic converter, vacuum booster and so on, are elaborated in the paper. The effect of these key components on cold start, hot start, emission, idle and OBD calibration are researched. The characteristic of mini-vehicle calibration is summarized with cases.

  13. Fitting aerodynamics and propulsion into the puzzle

    Science.gov (United States)

    Johnston, Patrick J.; Whitehead, Allen H., Jr.; Chapman, Gary T.

    1987-01-01

    The development of an airbreathing single-stage-to-orbit vehicle, in particular the problems of aerodynamics and propulsion integration, is examined. The boundary layer transition on constant pressure surfaces at hypersonic velocities, and the effects of noise on the transition are investigated. The importance of viscosity, real-gas effects, and drag at hypersonic speeds is discussed. A propulsion system with sufficient propulsive lift to enhance the performance of the vehicle is being developed. The difficulties of engine-airframe integration are analyzed.

  14. Energy Efficiency Comparison between Hydraulic Hybrid and Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jia-Shiun Chen

    2015-05-01

    Full Text Available Conventional vehicles tend to consume considerable amounts of fuel, which generates exhaust gases and environmental pollution during intermittent driving cycles. Therefore, prospective vehicle designs favor improved exhaust emissions and energy consumption without compromising vehicle performance. Although pure electric vehicles feature high performance and low pollution characteristics, their limitations are their short driving range and high battery costs. Hybrid electric vehicles (HEVs are comparatively environmentally friendly and energy efficient, but cost substantially more compared with conventional vehicles. Hydraulic hybrid vehicles (HHVs are mainly operated using engines, or using alternate combinations of engine and hydraulic power sources while vehicles accelerate. When the hydraulic system accumulator is depleted, the conventional engine reengages; concurrently, brake-regenerated power is recycled and reused by employing hydraulic motor–pump modules in circulation patterns to conserve fuel and recycle brake energy. This study adopted MATLAB Simulink to construct complete HHV and HEV models for backward simulations. New European Driving Cycles were used to determine the changes in fuel economy. The output of power components and the state-of-charge of energy could be retrieved. Varying power component models, energy storage component models, and series or parallel configurations were combined into seven different vehicle configurations: the conventional manual transmission vehicle, series hybrid electric vehicle, series hydraulic hybrid vehicle, parallel hybrid electric vehicle, parallel hydraulic hybrid vehicle, purely electric vehicle, and hydraulic-electric hybrid vehicle. The simulation results show that fuel consumption was 21.80% lower in the series hydraulic hybrid vehicle compared to the series hybrid electric vehicle; additionally, fuel consumption was 3.80% lower in the parallel hybrid electric vehicle compared to the

  15. Distributed Propulsion featuring Boundary Layer Ingestion Engines for the Blended Wing Body Subsonic Transport

    OpenAIRE

    Kok, H.J.M.; Voskuijl, M.; Van Tooren, M.J.L.

    2010-01-01

    The blended wing body aircraft is one of the promising contenders for the next generation large transport aircraft. This aircraft is particularly suitable for the use of boundary layer ingestion engines. Results published in literature suggest that it might be beneficial to have a large number of these engines (distributed propulsion). A conceptual design study is therefore performed to determine the potential benefits of boundary layer ingestion engines for a conventional number of engines i...

  16. Are Upper-Body Axial Symptoms a Feature of Early Parkinson’s Disease?

    Science.gov (United States)

    Moreau, Caroline; Baille, Guillaume; Delval, Arnaud; Tard, Céline; Perez, Thierry; Danel-Buhl, Nicolas; Seguy, David; Labreuche, Julien; Duhamel, Alain; Delliaux, Marie; Dujardin, Kathy; Defebvre, Luc

    2016-01-01

    Background Axial disorders are considered to appear late in the course of Parkinson’s disease (PD). The associated impact on quality of life (QoL) and survival and the lack of an effective treatment mean that understanding and treating axial disorders is a key challenge. However, upper-body axial disorders (namely dysarthria, swallowing and breathing disorders) have never been prospectively assessed in early-stage PD patients. Objectives To characterize upper-body axial symptoms and QoL in consecutive patients with early-stage PD. Methods We prospectively enrolled 66 consecutive patients with early-stage PD (less than 3 years of disease progression) and assessed dysarthria, dysphagia and respiratory function (relative to 36 controls) using both objective and patient-reported outcomes. Results The mean disease duration was 1.26 years and the mean UPDRS motor score was 19.4 out of 108. 74% of the patients presented slight dysarthria (primarily dysprosodia). Men appeared to be more severely affected (i.e. dysphonia). This dysfunction was strongly correlated with low swallowing speed (despite the absence of complaints about dysphagia), respiratory insufficiency and poor QoL. Videofluorography showed that oral-phase swallowing disorders affected 60% of the 31 tested patients and that pharyngeal-phase disorders affected 21%. 24% of the patients reported occasional dyspnea, which was correlated with anxiety in women but not in men. Marked diaphragmatic dysfunction was suspected in 42% of the patients (predominantly in men). Conclusion Upper body axial symptoms were frequent in men with early-stage PD, whereas women presented worst non-motor impairments. New assessment methods are required because currently available tools do not reliably detect these upper-body axial disorders. PMID:27654040

  17. 汽车气动升力风洞试验值的修正方法%Correction Method for the Wind Tunnel Test Value of Vehicle Aerodynamic Lift

    Institute of Scientific and Technical Information of China (English)

    李启良; 杨志刚; 陈力

    2015-01-01

    [ Abstract] Both numerical simulation and wind tunnel test are conducted to study the additional lift genera-ted by moving belts in automotive wind tunnel with the simulation and test results obtained in terms of the static pressure coefficients and lift coefficients of front and rear belts. It is found by the numerical simulation on the change in the static pressure coefficients of moving belts between stationary and moving conditions that the additional lift coefficient of front belt in moving condition is only 0.004 larger than that in static condition while it is 0.008 lar-ger for rear belt. By combining the test data in stationary condition with the numerical simulation results in both sta-tionary and moving conditions, the correction formulae for the aerodynamic lift coefficients of automotive wind tunnel in moving condition are given and hence the real lift coefficient of tested vehicle can be obtained.%分别采用数值模拟和风洞试验,研究汽车风洞移动带产生的附加升力,获得前后轮移动带静压系数和附加升力系数的数值模拟和试验结果。接着通过对静止和运动工况移动带静压系数变化的数值模拟,发现由静止工况变为运动工况后,前轮带的附加升力系数仅增加0郾004,而后轮带增加0郾008。结合静止工况的试验数据和静止与运动工况的数值模拟结果,给出了运动工况汽车风洞气动升力系数的修正公式,从而可获得被测车辆的真实升力系数。

  18. Many-body effects and excitonic features in 2D biphenylene carbon

    International Nuclear Information System (INIS)

    The remarkable excitonic effects in low dimensional materials in connection to large binding energies of excitons are of great importance for research and technological applications such as in solar energy and quantum information processing as well as for fundamental investigations. In this study, the unique electronic and excitonic properties of the two dimensional carbon network biphenylene carbon were investigated with GW approach and the Bethe-Salpeter equation accounting for electron correlation effects and electron-hole interactions, respectively. Biphenylene carbon exhibits characteristic features including bright and dark excitons populating the optical gap of 0.52 eV and exciton binding energies of 530 meV as well as a technologically relevant intrinsic band gap of 1.05 eV. Biphenylene carbon’s excitonic features, possibly tuned, suggest possible applications in the field of solar energy and quantum information technology in the future

  19. Detection of 'archaeological features' among reflectance spectra of natural soils and archaeological soils using principal component analysis (PCA)

    Science.gov (United States)

    Choi, Yoon Jung; Lampel, Johannes; Jordan, David; Fiedler, Sabine; Wagner, Thomas

    2016-04-01

    Archaeological terminology 'soil-mark' refers to buried archaeological features being visible on the ground surface. Soil-marks have been identified by archaeologists based on their personal experience and knowledge. This study suggests a quantitative spectral analysis method to detect such archaeological features. This study identifies 'archaeological spectra' (reflectance spectra from surfaces containing archaeological materials) among various soil spectra using PCA (principal component analysis). Based on the results of the PCA, a difference (D) between the original spectrum and modified spectrum, which represents the principal component (PC) values of natural soils, can be determined. If the difference D between the two spectra is small, then the spectrum is similar to the spectral features of natural soils. If not, it identifies that the spectrum is more likely to be non-natural soil, probably an archaeological material. The method is applied on soil spectra from a prehistoric settlement site in Calabria, Italy. For the spectral range between 400 to 700nm, the difference value D for archaeological material ranges from 0.11 to 0.73 (the value varies depending on the number of PCs used). For natural soil, D ranges only from 0.04 to 0.09. The results shows D value is significantly larger for archaeological spectra, which indicates that the method can be applied to identify archaeological material among an unknown group of soil spectra, if a set of samples of natural soils exists. The study will present results of applying this method to various wavelength ranges and spectra from different sites. The major aim is to find optimised settings of the PCA method which can be applied in a universal way for identifying archaeological spectra.

  20. Reinforced aerodynamic profile

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention relates to the prevention of deformations in an aerodynamic profile caused by lack of resistance to the bending moment forces that are created when such a profile is loaded in operation. More specifically, the invention relates to a reinforcing element inside an aerodynamic ...... profile and a method for the construction thereof. The profile is intended for, but not limited to, useas a wind turbine blade, an aerofoil device or as a wing profile used in the aeronautical industry....

  1. Clinical features of muscle dysmorphia among males with body dysmorphic disorder

    OpenAIRE

    Pope, Courtney G.; Pope, Harrison G.; Menard, William; Fay, Christina; Olivardia, Roberto; Phillips, Katharine A.

    2005-01-01

    Muscle dysmorphia – a pathological preoccupation with muscularity – appears to be a form of body dysmorphic disorder (BDD) with a focus on muscularity. However, little is known about muscle dysmorphia in men with BDD, and no study has compared men with BDD who do and do not report muscle dysmorphia. To explore this issue, we reviewed the histories of 63 men with BDD; we compared those rated as having a history of muscle dysmorphia with those who had BDD but not muscle dysmorphia in several do...

  2. Examination of children's body composition and biomotoric features which attended summer football schools

    OpenAIRE

    INAN, Burak; DALIOGLU, Onder

    2014-01-01

    The purpose of the study is to examine body composition and biomotoric specifications of subjects who attended the football program for 8 weeks, 3 days a week.In the applied study, 50 subjects were chosen occasionally and voluntarily out of 125 football players. This study was applied on 8-13 aged male football players who attended summer football school in city of Gaziantep. Pre examination of the group was 1 week before 8 week training program, and post examination was 1 week after 8 week t...

  3. Body Mass Index, Migraine, Migraine Frequency, and Migraine Features in Women

    OpenAIRE

    Winter, Anke C; Berger, Klaus; Buring, Julie E.; Kurth, Tobias

    2009-01-01

    We evaluated the association of body mass index (BMI) with migraine and migraine specifics in a cross-sectional study of 63,467 women. 12,613 (19.9%) women reported any history of migraine, of whom 9,195 had active migraine. Compared with women without migraine and a BMI =35kg/m2 had adjusted odds ratios (ORs) (95%CIs) of 1.03 (0.95-1.12) for any history of migraine. Findings were similar for active migraineurs. Women with a BMI of >=35kg/m2 had increased risk for low and high migraine freque...

  4. Reduced vehicle model for optimizing the Body In White (BIW) with respect to vehicle dynamics and handling; Reduziertes Berechnungsmodell fuer ein Kraftfahrzeug zur Auslegung der Karosserie hinsichtlich fahrdynamischer Zielgroessen

    Energy Technology Data Exchange (ETDEWEB)

    Kolk, O. [Bayerische Motoren Werke AG (BMW), Muenchen (Germany). Karosserieentwicklung Anbauteile/Technologiekonzepte

    2005-07-01

    The author's investigations showed that the meeting of dynamic criteria for car body and chassis will not necessary serve to optimize car dynamics in general. The study describe the identification of secondary stiffness criteria and supplementary load cases with which the general dynamics of the car can be calculated and predicted. For fast and automatic motor vehicle assessment and optimization, a reduced calculation model is introduced in which the chassis is replaced by intersecting loads on the car body and the loads on the car body is modelled as a quasistatic load at a given moment of the driving process. (orig.)

  5. Aerodynamics support of research instrument development

    Science.gov (United States)

    Miller, L. Scott

    1990-01-01

    A new velocimetry system is currently being developed at NASA LaRC. The device, known as a Doppler global velocimeter (DGV), can record three velocity components within a plane simultaneously and in near real time. To make measurements the DGV, like many other velocimetry systems, relies on the scattering of light from numerous small particles in a flow field. The particles or seeds are illuminated by a sheet of laser light and viewed by two CCD cameras. The scattered light from the particles will have a frequency which is a function of the source laser light frequency, the viewing angle, and most importantly the seed velocities. By determining the scattered light intensity the velocity can be measured at all points within the light sheet simultaneously. Upon completion of DGV component construction and initial check out a series of tests in the Basic Aerodynamic Research (wind) Tunnel (BART) are scheduled to verify instrument operation and accuracy. If the results are satisfactory, application of the DGV to flight measurements on the F-18 High Alpha Research Vehicle (HARV) are planned. The DGV verification test in the BART facility will utilize a 75 degree swept delta wing model. A major task undertaken this summer included evaluation of previous results for this model. A specific series of tests matching exactly the previous tests and exploring new DGV capabilities were developed and suggested. Another task undertaken was to study DGV system installation possibilities in the F-18 HARV aircraft. In addition, a simple seeding system modification was developed and utilized to make Particle Imaging Velocimetry (PIV) measurements in the BART facility.

  6. Multi-objective component sizing of a power-split plug-in hybrid electric vehicle powertrain using Pareto-based natural optimization machines

    Science.gov (United States)

    Mozaffari, Ahmad; Vajedi, Mahyar; Chehresaz, Maryyeh; Azad, Nasser L.

    2016-03-01

    The urgent need to meet increasingly tight environmental regulations and new fuel economy requirements has motivated system science researchers and automotive engineers to take advantage of emerging computational techniques to further advance hybrid electric vehicle and plug-in hybrid electric vehicle (PHEV) designs. In particular, research has focused on vehicle powertrain system design optimization, to reduce the fuel consumption and total energy cost while improving the vehicle's driving performance. In this work, two different natural optimization machines, namely the synchronous self-learning Pareto strategy and the elitism non-dominated sorting genetic algorithm, are implemented for component sizing of a specific power-split PHEV platform with a Toyota plug-in Prius as the baseline vehicle. To do this, a high-fidelity model of the Toyota plug-in Prius is employed for the numerical experiments using the Autonomie simulation software. Based on the simulation results, it is demonstrated that Pareto-based algorithms can successfully optimize the design parameters of the vehicle powertrain.

  7. 基于高效数值方法的高速飞行器气动力热特性快速预测研究%Fast prediction based on effective numerical method for aerodynamic force and heat of high speed vehicles

    Institute of Scientific and Technical Information of China (English)

    王荣; 张学军; 纪楚群

    2015-01-01

    结合空间推进数值模拟方法和流线追踪法发展了气动力、热快速预测技术。针对高速飞行器的算例研究表明,相对常规时间推进方法,基于空间推进法的气动快速预测方法计算效率提高了一个量级,而两者气动力计算精度相当,相对实验热流预测误差在20%以内。所发展的技术为适应气动外形快速选型和优化设计需求提供了有效的方法。%A fast aerodynamic characteristics prediction technique is developed to predict aer-odynamic force and heat,combining effective space marching numerical method with engineering method based on surface stream tracking technique.Hypersonic aerodynamic forces are obtained effectively by solving the Euler equations numerically with fast space marching method.In order to calculate the heat flux,an engineering method,called tracking the surface stream trace based on the axisymmetric analogue technique and boundary layer theory,is adopted and developed to be applicable for complex geometry.The inviscid flow parameters and surface stream lines re-quired in the engineering method are obtained from above mentioned inviscous numerical flow fields.The proposed method for aerodynamic force and heat prediction is applied to high speed vehicles,the results show that the space marching method saves the computational cost enor-mously,approximately one order less comparing to the time marching method,while the two methods have similar precision in aerodynamic force evaluation.The predicted error of heat flux is within 20% comparing to that of wind tunnel test.The technique promoted is an effective ap-proach suitable for the needs of fast aerodynamic configuration design and optimization.

  8. Characterization of relative growth of empty body and carcass components for bulls from a five-breed diallel.

    Science.gov (United States)

    Baker, J F; Bryson, W L; Sanders, J O; Dahm, P F; Cartwright, T C; Ellis, W C; Long, C R

    1991-08-01

    Slaughter and carcass data were obtained on 197 bulls produced in a diallel involving Angus, Brahman, Hereford, Holstein and Jersey that were slaughtered at either 6, 9, 12, 15, 18, 24, or 30 mo of age. Bulls were given ad libitum access to a 72% TDN diet on an individual basis from 6 mo of age until slaughter. Empty body weight (EBWT) was determined as the sum of the weights of blood, hide, hard drop, soft drop (minus contents of the digestive tract), and carcass weight (CWT), which were recorded at slaughter. Carcass protein (CPROT) and fat (CFAT) were based on weights and chemical analyses of lean and fat tissue and bone of the carcass. Empty body protein (EBPROT) and fat (EBFAT) were based on weights and chemical estimates of the components of the empty body. Growth of EBWT, EBPROT, EBFAT, CWT, CPROT, and CFAT relative to either live weight (LWT), EBWT, or CWT were investigated using the allometric equation. Breed-type differences existed (P less than .01) for the growth of EBWT relative to LWT. Comparisons of general combining abilities revealed that Angus, Hereford, and Jersey generally had lower maturing rates of EBWT relative to LWT and that Brahman and Holstein had higher maturing rates. Across breed-type, relative growth rates indicated that fat and protein were later-maturing components relative to LWT, EBWT, or CWT, which implies that other components mature relatively earlier. Relative maturing rates of components studied were not important in explaining differences in body composition that have been previously reported for these breed-types. PMID:1894551

  9. Characterization of relative growth of empty body and carcass components for bulls from a five-breed diallel.

    Science.gov (United States)

    Baker, J F; Bryson, W L; Sanders, J O; Dahm, P F; Cartwright, T C; Ellis, W C; Long, C R

    1991-08-01

    Slaughter and carcass data were obtained on 197 bulls produced in a diallel involving Angus, Brahman, Hereford, Holstein and Jersey that were slaughtered at either 6, 9, 12, 15, 18, 24, or 30 mo of age. Bulls were given ad libitum access to a 72% TDN diet on an individual basis from 6 mo of age until slaughter. Empty body weight (EBWT) was determined as the sum of the weights of blood, hide, hard drop, soft drop (minus contents of the digestive tract), and carcass weight (CWT), which were recorded at slaughter. Carcass protein (CPROT) and fat (CFAT) were based on weights and chemical analyses of lean and fat tissue and bone of the carcass. Empty body protein (EBPROT) and fat (EBFAT) were based on weights and chemical estimates of the components of the empty body. Growth of EBWT, EBPROT, EBFAT, CWT, CPROT, and CFAT relative to either live weight (LWT), EBWT, or CWT were investigated using the allometric equation. Breed-type differences existed (P less than .01) for the growth of EBWT relative to LWT. Comparisons of general combining abilities revealed that Angus, Hereford, and Jersey generally had lower maturing rates of EBWT relative to LWT and that Brahman and Holstein had higher maturing rates. Across breed-type, relative growth rates indicated that fat and protein were later-maturing components relative to LWT, EBWT, or CWT, which implies that other components mature relatively earlier. Relative maturing rates of components studied were not important in explaining differences in body composition that have been previously reported for these breed-types.

  10. A Comparing of Body Composition Components in Physically Active and Inactive Male Students of Sharoud University of Technology

    Directory of Open Access Journals (Sweden)

    Hassan Bahrololoum

    2010-01-01

    Full Text Available Introduction: Obesity is a serious health problem that reduces life expectancy by increasing one's risk of developing coronary artery disease, hypertension, type 2 diabetes, obstructive pulmonary disease, osteoarthritis and certain types of cancer. Moreover, body composition is divided into fat and fat free mass components. Research shows that physical activity is an important factor that affects body composition. This research aimed at estimating and comparing the body composition components of physically active and inactive male student of Shahroud University of technologyMethods: Participants of this study were 70 inactive male students with average age of (20.86±1.72 years and 65 physically active male students with average age of (20.86±1.72 years. The participants were randomly selected through stratified sampling procedure from various faculties and different admission years. Body composition was estimated with Body composition analyzer system that measured body composition components using bioelectrical impedance method.Results: Data analysis with SPSS-15 software revealed that: average of BF% in physically active sample was (13.43±3.15 and average of inactive samples was (16.73±6.16 which statistically showed significant difference (P<0.001 ; the LBM in physically active samples was (60.27±8.05 Kg and average of inactive samples was (56.43±7.6 Kg which statistically showed significant difference (P<0.005; the average of BMI in physically active sample was (22.62±2.8 kgm and average of inactive samples was (22.25±3.84 kgm which statistically did not show significant difference (P=0.519; the WHR average of physically active samples was (0.798±.03m and average of inactive samples was (0.81±.06m and there was not a significant difference between the two groups. Conclusion: These results revealed that body composition of physically active students were better than that of the inactive ones, so it can be concluded that there is a

  11. Hybrid-Wing-Body Vehicle Composite Fuselage Analysis and Case Study

    Science.gov (United States)

    Mukhopadhyay, Vivek

    2014-01-01

    Recent progress in the structural analysis of a Hybrid Wing-Body (HWB) fuselage concept is presented with the objective of structural weight reduction under a set of critical design loads. This pressurized efficient HWB fuselage design is presently being investigated by the NASA Environmentally Responsible Aviation (ERA) project in collaboration with the Boeing Company, Huntington Beach. The Pultruded Rod-Stiffened Efficient Unitized Structure (PRSEUS) composite concept, developed at the Boeing Company, is approximately modeled for an analytical study and finite element analysis. Stiffened plate linear theories are employed for a parametric case study. Maximum deflection and stress levels are obtained with appropriate assumptions for a set of feasible stiffened panel configurations. An analytical parametric case study is presented to examine the effects of discrete stiffener spacing and skin thickness on structural weight, deflection and stress. A finite-element model (FEM) of an integrated fuselage section with bulkhead is developed for an independent assessment. Stress analysis and scenario based case studies are conducted for design improvement. The FEM model specific weight of the improved fuselage concept is computed and compared to previous studies, in order to assess the relative weight/strength advantages of this advanced composite airframe technology

  12. Physical Activity Advertisements That Feature Daily Well-Being Improve Autonomy and Body Image in Overweight Women but Not Men

    Directory of Open Access Journals (Sweden)

    Michelle L. Segar

    2012-01-01

    Full Text Available The reasons for exercising that are featured in health communications brand exercise and socialize individuals about why they should be physically active. Discovering which reasons for exercising are associated with high-quality motivation and behavioral regulation is essential to promoting physical activity and weight control that can be sustained over time. This study investigates whether framing physical activity in advertisements featuring distinct types of goals differentially influences body image and behavioral regulations based on self-determination theory among overweight and obese individuals. Using a three-arm randomized trial, overweight and obese women and men (aged 40–60 yr, n=1690 read one of three ads framing physical activity as a way to achieve (1 better health, (2 weight loss, or (3 daily well-being. Framing effects were estimated in an ANOVA model with pairwise comparisons using the Bonferroni correction. This study showed that there are immediate framing effects on physical activity behavioral regulations and body image from reading a one-page advertisement about physical activity and that gender and BMI moderate these effects. Framing physical activity as a way to enhance daily well-being positively influenced participants’ perceptions about the experience of being physically active and enhanced body image among overweight women, but not men. The experiment had less impact among the obese study participants compared to those who were overweight. These findings support a growing body of research suggesting that, compared to weight loss, framing physical activity for daily well-being is a better gain-frame message for overweight women in midlife.

  13. Physical activity advertisements that feature daily well-being improve autonomy and body image in overweight women but not men.

    Science.gov (United States)

    Segar, Michelle L; Updegraff, John A; Zikmund-Fisher, Brian J; Richardson, Caroline R

    2012-01-01

    The reasons for exercising that are featured in health communications brand exercise and socialize individuals about why they should be physically active. Discovering which reasons for exercising are associated with high-quality motivation and behavioral regulation is essential to promoting physical activity and weight control that can be sustained over time. This study investigates whether framing physical activity in advertisements featuring distinct types of goals differentially influences body image and behavioral regulations based on self-determination theory among overweight and obese individuals. Using a three-arm randomized trial, overweight and obese women and men (aged 40-60 yr, n = 1690) read one of three ads framing physical activity as a way to achieve (1) better health, (2) weight loss, or (3) daily well-being. Framing effects were estimated in an ANOVA model with pairwise comparisons using the Bonferroni correction. This study showed that there are immediate framing effects on physical activity behavioral regulations and body image from reading a one-page advertisement about physical activity and that gender and BMI moderate these effects. Framing physical activity as a way to enhance daily well-being positively influenced participants' perceptions about the experience of being physically active and enhanced body image among overweight women, but not men. The experiment had less impact among the obese study participants compared to those who were overweight. These findings support a growing body of research suggesting that, compared to weight loss, framing physical activity for daily well-being is a better gain-frame message for overweight women in midlife.

  14. Winter body mass and over-ocean flocking as components of danger management by Pacific dunlins

    NARCIS (Netherlands)

    Ydenberg, R.C.; Dekker, D.; Kaiser, G.; Shepherd, P.C.F.; Ogden, L.E.; Rickards, K.; Lank, D.B.

    2010-01-01

    Background: We compared records of the body mass and roosting behavior of Pacific dunlins (Calidris alpina pacifica) wintering on the Fraser River estuary in southwest British Columbia between the 1970s and the 1990s. 'Over-ocean flocking' is a relatively safe but energetically-expensive alternative

  15. The effect of psoriasis treatment on body composition, components of metabolic syndrome and psoriatic arthritis

    Directory of Open Access Journals (Sweden)

    Funda Tamer

    2015-03-01

    Full Text Available Background and Design: Psoriasis is a chronic inflammatory immun mediated skin disorder with unknown etiology. The chronic inflammation in psoriasis have role in the development of metabolic and vascular disorders related with associating comorbidities. Recent studies have suggested a strong association exists between metabolic syndrome, obesity and complexity of the association between psoriasis, body mass index (BMI and psoriasis tratment. In this study, our aim was to investigate the effect of psoriasis treatment with methotrexate, cyclosporine and biological agents on body composition, comorbidities and associated laboratory findings. Materials and Methods: Seventy-nine patients treated with methotrexate, cyclosporin and biological agents were included in our study. Demographic characteristics, body composition analysis, psoriasis related comorbidities and laboratory examinations were evaluated before and after 12 weeks of systemic treatment. Results: Comorbidities and metabolic syndrome tended to be more frequent in the anti tumor necrosis factor alpha (anti-TNF-α treated group. Increase in body fat and weight detected in patiens receiving biologic drug therapy. Conclusion: The results of our study showed that severe psoriasis patients with longer disease duration were more likely to have metabolic syndrome because of severe and long term inflammation in pathogenesis of comorbidities.

  16. Fatigue assessment of vibrating rail vehicle bogie components under non-Gaussian random excitations using power spectral densities

    Science.gov (United States)

    Wolfsteiner, Peter; Breuer, Werner

    2013-10-01

    extensive measured loads in time domain without losing the necessary accuracy for the fatigue load results. These long measurements may even represent the whole application range of the railway vehicle. The presented work demonstrates the application of this method to railway vehicle components subjected to random vibrations caused by the wheel rail contact. Extensive measurements of axle box accelerations have been used to verify the proposed procedure for this class of railway vehicle applications. The linearity is not a real limitation, because the structural vibrations caused by the random excitations are usually small for rail vehicle applications. The impact of nonlinearities is usually covered by separate nonlinear models and only needed for the deterministic part of the loads. Linear vibration systems subjected to Gaussian vibrations respond with vibrations having also a Gaussian distribution. A non-Gaussian distribution in the excitation signal produces also a non-Gaussian response with statistical properties different from these excitations. A drawback is the fact that there is no simple mathematical relation between excitation and response concerning these deviations from the Gaussian distribution (see e.g. Ito calculus [6], which is usually not part of commercial codes!). There are a couple of well-established procedures for the prediction of fatigue load spectra from PSDs designed for Gaussian loads (see [4]); the question of the impact of non-Gaussian distributions on the fatigue load prediction has been studied for decades (see e.g. [3,4,11-13]) and is still subject of the ongoing research; e.g. [13] proposed a procedure, capable of considering non-Gaussian broadbanded loads. It is based on the knowledge of the response PSD and some statistical data, defining the non-Gaussian character of the underlying time signal. As already described above, these statistical data are usually not available for a PSD vibration response that has been calculated in the

  17. Winter body mass and over-ocean flocking as components of danger management by Pacific dunlins

    Directory of Open Access Journals (Sweden)

    Ogden Lesley

    2010-01-01

    Full Text Available Abstract Background We compared records of the body mass and roosting behavior of Pacific dunlins (Calidris alpina pacifica wintering on the Fraser River estuary in southwest British Columbia between the 1970s and the 1990s. 'Over-ocean flocking' is a relatively safe but energetically-expensive alternative to roosting during the high tide period. Fat stores offer protection against starvation, but are a liability in escape performance, and increase flight costs. Peregrine falcons (Falco peregrinus were scarce on the Fraser River estuary in the 1970s, but their numbers have since recovered, and they prey heavily on dunlins. The increase has altered the balance between predation and starvation risks for dunlins, and thus how dunlins regulate roosting behavior and body mass to manage the danger. We therefore predicted an increase in the frequency of over-ocean flocking as well as a decrease in the amount of fat carried by dunlins over these decades. Results Historical observations indicate that over-ocean flocking of dunlins was rare prior to the mid-1990s and became common thereafter. Residual body masses of dunlins were higher in the 1970s, with the greatest difference between the decades coinciding with peak peregrine abundance in October, and shrinking over the course of winter as falcon seasonal abundance declines. Whole-body fat content of dunlins was lower in the 1990s, and accounted for most of the change in body mass. Conclusions Pacific dunlins appear to manage danger in a complex manner that involves adjustments both in fat reserves and roosting behavior. We discuss reasons why over-ocean flocking has apparently become more common on the Fraser estuary than at other dunlin wintering sites.

  18. In vivo recording of aerodynamic force with an aerodynamic force platform: from drones to birds.

    Science.gov (United States)

    Lentink, David; Haselsteiner, Andreas F; Ingersoll, Rivers

    2015-03-01

    Flapping wings enable flying animals and biomimetic robots to generate elevated aerodynamic forces. Measurements that demonstrate this capability are based on experiments with tethered robots and animals, and indirect force calculations based on measured kinematics or airflow during free flight. Remarkably, there exists no method to measure these forces directly during free flight. Such in vivo recordings in freely behaving animals are essential to better understand the precise aerodynamic function of their flapping wings, in particular during the downstroke versus upstroke. Here, we demonstrate a new aerodynamic force platform (AFP) for non-intrusive aerodynamic force measurement in freely flying animals and robots. The platform encloses the animal or object that generates fluid force with a physical control surface, which mechanically integrates the net aerodynamic force that is transferred to the earth. Using a straightforward analytical solution of the Navier-Stokes equation, we verified that the method is accurate. We subsequently validated the method with a quadcopter that is suspended in the AFP and generates unsteady thrust profiles. These independent measurements confirm that the AFP is indeed accurate. We demonstrate the effectiveness of the AFP by studying aerodynamic weight support of a freely flying bird in vivo. These measurements confirm earlier findings based on kinematics and flow measurements, which suggest that the avian downstroke, not the upstroke, is primarily responsible for body weight support during take-off and landing.

  19. In vivo recording of aerodynamic force with an aerodynamic force platform: from drones to birds.

    Science.gov (United States)

    Lentink, David; Haselsteiner, Andreas F; Ingersoll, Rivers

    2015-03-01

    Flapping wings enable flying animals and biomimetic robots to generate elevated aerodynamic forces. Measurements that demonstrate this capability are based on experiments with tethered robots and animals, and indirect force calculations based on measured kinematics or airflow during free flight. Remarkably, there exists no method to measure these forces directly during free flight. Such in vivo recordings in freely behaving animals are essential to better understand the precise aerodynamic function of their flapping wings, in particular during the downstroke versus upstroke. Here, we demonstrate a new aerodynamic force platform (AFP) for non-intrusive aerodynamic force measurement in freely flying animals and robots. The platform encloses the animal or object that generates fluid force with a physical control surface, which mechanically integrates the net aerodynamic force that is transferred to the earth. Using a straightforward analytical solution of the Navier-Stokes equation, we verified that the method is accurate. We subsequently validated the method with a quadcopter that is suspended in the AFP and generates unsteady thrust profiles. These independent measurements confirm that the AFP is indeed accurate. We demonstrate the effectiveness of the AFP by studying aerodynamic weight support of a freely flying bird in vivo. These measurements confirm earlier findings based on kinematics and flow measurements, which suggest that the avian downstroke, not the upstroke, is primarily responsible for body weight support during take-off and landing. PMID:25589565

  20. Numerical Simulation Research of Loitering Munitions Aerodynamics

    Institute of Scientific and Technical Information of China (English)

    HE Guang-lin; JI Xiu-ling; ZHANG Tai-heng

    2009-01-01

    Aerodynamics of loitering munition is studied in this paper. The aerodynamic characteristics of loitering munition with non-circular body and body-airfoil-empennage combination are calculated numerically at Ma=0.4 based on multi-griddings patching technology, in the range of angle of attack -4°-10°, and the analytical results were compared with those from wind tunnel experiments, they show a good consistency. Analysis of the results showed that the normal force generated by non-circular cross-section missile increases with the angle of attack. At α≥6°, normal force achieved by missile body can take up to 10% of the total lift. Together with the lifting surface, the loitering munitions can provide a better lift to drag ratio, an improved weapon range and a good longitudinal stability.

  1. Structured covariance principal component analysis for real-time onsite feature extraction and dimensionality reduction in hyperspectral imaging.

    Science.gov (United States)

    Zabalza, Jaime; Ren, Jinchang; Ren, Jie; Liu, Zhe; Marshall, Stephen

    2014-07-10

    Presented in a three-dimensional structure called a hypercube, hyperspectral imaging suffers from a large volume of data and high computational cost for data analysis. To overcome such drawbacks, principal component analysis (PCA) has been widely applied for feature extraction and dimensionality reduction. However, a severe bottleneck is how to compute the PCA covariance matrix efficiently and avoid computational difficulties, especially when the spatial dimension of the hypercube is large. In this paper, structured covariance PCA (SC-PCA) is proposed for fast computation of the covariance matrix. In line with how spectral data is acquired in either the push-broom or tunable filter method, different implementation schemes of SC-PCA are presented. As the proposed SC-PCA can determine the covariance matrix from partial covariance matrices in parallel even without prior deduction of the mean vector, it facilitates real-time data analysis while the hypercube is acquired. This has significantly reduced the scale of required memory and also allows efficient onsite feature extraction and data reduction to benefit subsequent tasks in coding and compression, transmission, and analytics of hyperspectral data.

  2. A review of dynamic characteristics of magnetically levitated vehicle systems

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Y.; Chen, S.S.

    1995-11-01

    The dynamic response of magnetically levitated (maglev) ground transportation systems has important consequences for safety and ride quality, guideway design, and system costs. Ride quality is determined by vehicle response and by environmental factors such as humidity and noise. The dynamic response of the vehicles is the key element in determining ride quality, while vehicle stability is an important safety-related element. To design a guideway that provides acceptable ride quality in the stable region, vehicle dynamics must be understood. Furthermore, the trade-off between guideway smoothness and levitation and control systems must be considered if maglev systems are to be economically feasible. The link between the guideway and the other maglev components is vehicle dynamics. For a commercial maglev system, vehicle dynamics must be analyzed and tested in detail. This report, which reviews various aspects of the dynamic characteristics, experiments and analysis, and design guidelines for maglev systems, discusses vehicle stability, motion dependent magnetic force components, guideway characteristics, vehicle/ guideway interaction, ride quality, suspension control laws, aerodynamic loads and other excitations, and research needs.

  3. A component modes projection and assembly model reduction methodology for articulated, multi-flexible body structures

    Science.gov (United States)

    Lee, Allan Y.; Tsuha, Walter S.

    1993-01-01

    A two-stage model reduction methodology, combining the classical Component Mode Synthesis (CMS) method and the newly developed Enhanced Projection and Assembly (EP&A) method, is proposed in this research. The first stage of this methodology, called the COmponent Modes Projection and Assembly model REduction (COMPARE) method, involves the generation of CMS mode sets, such as the MacNeal-Rubin mode sets. These mode sets are then used to reduce the order of each component model in the Rayleigh-Ritz sense. The resultant component models are then combined to generate reduced-order system models at various system configurations. A composite mode set which retains important system modes at all system configurations is then selected from these reduced-order system models. In the second stage, the EP&A model reduction method is employed to reduce further the order of the system model generated in the first stage. The effectiveness of the COMPARE methodology has been successfully demonstrated on a high-order, finite-element model of the cruise-configured Galileo spacecraft.

  4. Metabolic features of Protochlamydia amoebophila elementary bodies--a link between activity and infectivity in Chlamydiae.

    Directory of Open Access Journals (Sweden)

    Barbara S Sixt

    Full Text Available The Chlamydiae are a highly successful group of obligate intracellular bacteria, whose members are remarkably diverse, ranging from major pathogens of humans and animals to symbionts of ubiquitous protozoa. While their infective developmental stage, the elementary body (EB, has long been accepted to be completely metabolically inert, it has recently been shown to sustain some activities, including uptake of amino acids and protein biosynthesis. In the current study, we performed an in-depth characterization of the metabolic capabilities of EBs of the amoeba symbiont Protochlamydia amoebophila. A combined metabolomics approach, including fluorescence microscopy-based assays, isotope-ratio mass spectrometry (IRMS, ion cyclotron resonance Fourier transform mass spectrometry (ICR/FT-MS, and ultra-performance liquid chromatography mass spectrometry (UPLC-MS was conducted, with a particular focus on the central carbon metabolism. In addition, the effect of nutrient deprivation on chlamydial infectivity was analyzed. Our investigations revealed that host-free P. amoebophila EBs maintain respiratory activity and metabolize D-glucose, including substrate uptake as well as host-free synthesis of labeled metabolites and release of labeled CO2 from (13C-labeled D-glucose. The pentose phosphate pathway was identified as major route of D-glucose catabolism and host-independent activity of the tricarboxylic acid (TCA cycle was observed. Our data strongly suggest anabolic reactions in P. amoebophila EBs and demonstrate that under the applied conditions D-glucose availability is essential to sustain metabolic activity. Replacement of this substrate by L-glucose, a non-metabolizable sugar, led to a rapid decline in the number of infectious particles. Likewise, infectivity of Chlamydia trachomatis, a major human pathogen, also declined more rapidly in the absence of nutrients. Collectively, these findings demonstrate that D-glucose is utilized by P. amoebophila

  5. Wavelet Correlation Feature Scale Entropy and Fuzzy Support Vector Machine Approach for Aeroengine Whole-Body Vibration Fault Diagnosis

    Directory of Open Access Journals (Sweden)

    Cheng-Wei Fei

    2013-01-01

    Full Text Available In order to correctly analyze aeroengine whole-body vibration signals, Wavelet Correlation Feature Scale Entropy (WCFSE and Fuzzy Support Vector Machine (FSVM (WCFSE-FSVM method was proposed by fusing the advantages of the WCFSE method and the FSVM method. The wavelet coefficients were known to be located in high Signal-to-Noise Ratio (S/N or SNR scales and were obtained by the Wavelet Transform Correlation Filter Method (WTCFM. This method was applied to address the whole-body vibration signals. The WCFSE method was derived from the integration of the information entropy theory and WTCFM, and was applied to extract the WCFSE values of the vibration signals. Among the WCFSE values, the WFSE1 and WCFSE2 values on the scale 1 and 2 from the high band of vibration signal were believed to acceptably reflect the vibration feature and were selected to construct the eigenvectors of vibration signals as fault samples to establish the WCFSE-FSVM model. This model was applied to aeroengine whole-body vibration fault diagnosis. Through the diagnoses of four vibration fault modes and the comparison of the analysis results by four methods (SVM, FSVM, WESE-SVM, WCFSE-FSVM, it is shown that the WCFSE-FSVM method is characterized by higher learning ability, higher generalization ability and higher anti-noise ability than other methods in aeroengine whole-vibration fault analysis. Meanwhile, this present study provides a useful insight for the vibration fault diagnosis of complex machinery besides an aeroengine.

  6. Allometric Growth Patterns of Body and Carcass Components in Ardhi Goat

    OpenAIRE

    A. Al-Owaimer; Suliman, G.; A. El-Waziry; Metwally, H.; M. Abouheif

    2013-01-01

    This study aims to evaluate the developmental trends and the allometric growth values of various body parts and fat depots of the most prevailing indigenous Saudi goat. Thirty male Ardhi kids were serially slaughtered at 10, 15, 20, 25, 30 and 35 kg live weight. As the kids grew, the bones of hind limb grew at slower rates than the bones of the forelimb and within each limb, the cannon bone grew relatively at a slower rate than the upper skeletal bones. The allometric coefficients for the gro...

  7. Double dissociation of configural and featural face processing on P1 and P2 components as a function of spatial attention.

    Science.gov (United States)

    Wang, Hailing; Guo, Shichun; Fu, Shimin

    2016-08-01

    Face recognition relies on both configural and featural processing. Previous research has shown that P1 is sensitive to configural face processing, but it is unclear whether any component is sensitive to featural face processing; moreover, if there is such a component, its temporal sequence relative to P1 is unknown. Thus, to avoid confounding physical stimuli differences between configural and featural face processing on ERP components, a spatial attention paradigm was employed by instructing participants to attend an image stream (faces and houses) or an alphanumeric character stream. The interaction between attention and face processing type on P1 and P2 components indicates different mechanisms of configural and featural face processing as a function of spatial attention. The steady-state visual evoked potential (SSVEP) results clearly demonstrated that participants could selectively attend to different streams of information. Importantly, configural face processing elicited a larger posterior P1 (approximately 128 ms) than featural face processing, whereas P2 (approximately 248 ms) was greater for featural than for configural face processing under attended condition. The interaction between attention and face processing type (configural vs. featural) on P1 and P2 components indicates that there are different mechanisms of configural and featural face processing operating as functions of spatial attention. While the P1 result confirms previous findings separating configural and featural face processing, the newly observed P2 finding in the present study extends this separation to a double dissociation. Therefore, configural and featural face processing are modulated differently by spatial attention, and configural face processing precedes featural face processing. PMID:27167853

  8. Allometric Growth Patterns of Body and Carcass Components in Ardhi Goat

    Directory of Open Access Journals (Sweden)

    A. Al-Owaimer

    2013-10-01

    Full Text Available This study aims to evaluate the developmental trends and the allometric growth values of various body parts and fat depots of the most prevailing indigenous Saudi goat. Thirty male Ardhi kids were serially slaughtered at 10, 15, 20, 25, 30 and 35 kg live weight. As the kids grew, the bones of hind limb grew at slower rates than the bones of the forelimb and within each limb, the cannon bone grew relatively at a slower rate than the upper skeletal bones. The allometric coefficients for the growth of hot and cold carcass, liver, stomach compartments and lean relative to empty body weight were isogonic (b = 1.00, whereas coefficients of all internal fat depots, intermuscular and subcutaneous fat weights were heterogonic with the high growth impetus of b values greater than 1.00 (p<0.01. The developmental rates of the intestines and separated bones from cold carcass side were heterogonic with medium growth impetus. These results, showed that the highest growth coefficients were obtained for omental and perirenal fat indicating the late maturing characteristics of these depots, followed in a decreasing order by mesenteric and intermuscular fat, channel fat and finally subcutaneous and pericardial fat, which were the earliest developing depots.

  9. Moments of Inertia: Uninhabited Aerial Vehicle (UAV) Dryden Remotely Operated Integrated Drone (DROID)

    Science.gov (United States)

    Haro, Helida C.

    2010-01-01

    The objective of this research effort is to determine the most appropriate, cost efficient, and effective method to utilize for finding moments of inertia for the Uninhabited Aerial Vehicle (UAV) Dryden Remotely Operated Integrated Drone (DROID). A moment is a measure of the body's tendency to turn about its center of gravity (CG) and inertia is the resistance of a body to changes in its momentum. Therefore, the moment of inertia (MOI) is a body's resistance to change in rotation about its CG. The inertial characteristics of an UAV have direct consequences on aerodynamics, propulsion, structures, and control. Therefore, it is imperative to determine the precise inertial characteristics of the DROID.

  10. Moments of Inertia - Uninhabited Aerial Vehicle (UAV) Dryden Remotely Operated Integrated Drone (DROID)

    Science.gov (United States)

    Haro, Helida C.

    2010-01-01

    The objective of this research effort is to determine the most appropriate, cost efficient, and effective method to utilize for finding moments of inertia for the Uninhabited Aerial Vehicle (UAV) Dryden Remotely Operated Integrated Drone (DROID). A moment is a measure of the body's tendency to turn about its center of gravity (CG) and inertia is the resistance of a body to changes in its momentum. Therefore, the moment of inertia (MOI) is a body's resistance to change in rotation about its CG. The inertial characteristics of an UAV have direct consequences on aerodynamics, propulsion, structures, and control. Therefore, it is imperative to determine the precise inertial characteristics of the DROID.

  11. The Tanita SC-240 to Assess Body Composition in Pre-School Children: An Evaluation against the Three Component Model

    Science.gov (United States)

    Delisle Nyström, Christine; Henriksson, Pontus; Alexandrou, Christina; Löf, Marie

    2016-01-01

    Quick, easy-to-use, and valid body composition measurement options for young children are needed. Therefore, we evaluated the ability of the bioelectrical impedance (BIA) device, Tanita SC-240, to measure fat mass (FM), fat free mass (FFM) and body fatness (BF%) in 40 healthy, Swedish 5.5 years old children against the three component model (3C model). Average BF%, FM, and FFM for BIA were: 19.4% ± 3.9%, 4.1 ± 1.9 kg, and 16.4 ± 2.4 kg and were all significantly different (p < 0.001) from corresponding values for the 3C model (25.1% ± 5.5%, 5.3 ± 2.5 kg, and 15.2 ± 2.0 kg). Bland and Altman plots had wide limits of agreement for all body composition variables. Significant correlations ranging from 0.81 to 0.96 (p < 0.001) were found for BF%, FM, and FFM between BIA and the 3C model. When dividing the children into tertiles for BF%, 60% of children were classified correctly by means of BIA. In conclusion, the Tanita SC-240 underestimated BF% in comparison to the 3C model and had wide limits of agreement. Further work is needed in order to find accurate and easy-to-use methods for assessing body composition in pre-school children. PMID:27322313

  12. The Tanita SC-240 to Assess Body Composition in Pre-School Children: An Evaluation against the Three Component Model

    Directory of Open Access Journals (Sweden)

    Christine Delisle Nyström

    2016-06-01

    Full Text Available Quick, easy-to-use, and valid body composition measurement options for young children are needed. Therefore, we evaluated the ability of the bioelectrical impedance (BIA device, Tanita SC-240, to measure fat mass (FM, fat free mass (FFM and body fatness (BF% in 40 healthy, Swedish 5.5 years old children against the three component model (3C model. Average BF%, FM, and FFM for BIA were: 19.4% ± 3.9%, 4.1 ± 1.9 kg, and 16.4 ± 2.4 kg and were all significantly different (p < 0.001 from corresponding values for the 3C model (25.1% ± 5.5%, 5.3 ± 2.5 kg, and 15.2 ± 2.0 kg. Bland and Altman plots had wide limits of agreement for all body composition variables. Significant correlations ranging from 0.81 to 0.96 (p < 0.001 were found for BF%, FM, and FFM between BIA and the 3C model. When dividing the children into tertiles for BF%, 60% of children were classified correctly by means of BIA. In conclusion, the Tanita SC-240 underestimated BF% in comparison to the 3C model and had wide limits of agreement. Further work is needed in order to find accurate and easy-to-use methods for assessing body composition in pre-school children.

  13. Dynamics of the component of body composition in athletes playing sports with damage to the medial meniscus of the knee

    Directory of Open Access Journals (Sweden)

    Moh'd Khalil Moh'd Abdel Kader

    2012-11-01

    Full Text Available The question of the influence of the developed program of physical rehabilitation with the use of modern means and methods of recovery on the performance component of body composition in athletes playing sports after arthroscopic stapling the medial meniscus was considered. The analysis and synthesis of scientific and methodological data on the determination of body composition analysis techniques using bioelectrical resistance was shown. Found that long-term immobilization that accompanies the process of rehabilitation, reduced physical activity, vascular and other changes lead to muscle atrophy, restriction of mobility in the knee joint, trophic changes of the injured limb. The use of the physical rehabilitation programs allowed to state its high efficiency.

  14. Occluded Vehicle Segmentation Method Based on Corner Feature%基于角点特征的粘连车辆分割方法

    Institute of Scientific and Technical Information of China (English)

    陈舒; 刘秉瀚

    2013-01-01

    在智能交通系统粘连车辆的分割中,已有方法不能很好地保留车辆目标的轮廓细节.为此,提出一种基于角点特征的粘连车辆分割方法.采用帧差法提取运动车辆,借助数学形态学方法进行修复,引入长宽比、面积比等形态参数,判定粘连类别,结合Harris角点和K-means算法,检测并还原粘连区的角点,以实现粘连车辆的分割.实验结果表明,该方法能较好地保留车辆的轮廓细节信息,达到预期的实验效果.%How to segment the occluded vehicle is a key problem in Intelligent Transportation System(ITS).But the available algorithms can not preserve the edge characteristics of vehicle.This paper presents a new occluded vehicle segmentation method based on comer feature.It chooses the frame difference method to extract object and uses the mathematical morphology to repair,introduces two geometric parameters to judge the overlapping type,combines Harris comer detection with the K-means algorithm to identify the comer points which is in the overlapping area,realizes the segmentation for overlapping vehicle according to the axial symmetry.Experimental results show that this method can keep the vehicle's profile details information,and realizes the desired results.

  15. Shape distortion and thermo-mechanical properties of SOFC components from green tape to sintering body

    DEFF Research Database (Denmark)

    Teocoli, Francesca; Ni, De Wei; Tadesse Molla, Tesfaye;

    Sintering in ceramic materials is a critical process, especially when these are shaped as multilayer. From the green stage to the densification, the effects of organic additives removal, solid state diffusive phenomena, and either differential expansion or contraction of the layers can have...... critical effect on the final shape leading also failure, delamination etc. In this work, a tape-cast bi-layer structure for CGO and YSZ-(Sc) was studied during the thermal processing from debinding to the sintering. The bilayered samples undergo to several phenomena of shape instabilities and deformation...... due to binder burn out, differential shrinkage behavior and to a potential interfacial reaction between the two materials. To analyze the phenomena, shrinkage of SOFC components single layers and bilayered samples were measured insitu by optical dilatometer. The densification mismatch stress, due...

  16. Aerodynamically shaped vortex generators

    DEFF Research Database (Denmark)

    Hansen, Martin Otto Laver; Velte, Clara Marika; Øye, Stig;

    2016-01-01

    An aerodynamically shaped vortex generator has been proposed, manufactured and tested in a wind tunnel. The effect on the overall performance when applied on a thick airfoil is an increased lift to drag ratio compared with standard vortex generators. Copyright © 2015 John Wiley & Sons, Ltd....

  17. Specific features of modelling rules of monetary policy on the basis of hybrid regression models with a neural component

    Directory of Open Access Journals (Sweden)

    Lukianenko Iryna H.

    2014-01-01

    Full Text Available The article considers possibilities and specific features of modelling economic phenomena with the help of the category of models that unite elements of econometric regressions and artificial neural networks. This category of models contains auto-regression neural networks (AR-NN, regressions of smooth transition (STR/STAR, multi-mode regressions of smooth transition (MRSTR/MRSTAR and smooth transition regressions with neural coefficients (NCSTR/NCSTAR. Availability of the neural network component allows models of this category achievement of a high empirical authenticity, including reproduction of complex non-linear interrelations. On the other hand, the regression mechanism expands possibilities of interpretation of the obtained results. An example of multi-mode monetary rule is used to show one of the cases of specification and interpretation of this model. In particular, the article models and interprets principles of management of the UAH exchange rate that come into force when economy passes from a relatively stable into a crisis state.

  18. Mead Crater, Venus - Aerodynamic roughness of wind streaks

    Science.gov (United States)

    Williams, K. K.; Greeley, R.

    1997-03-01

    Radar backscatter images of Venus returned by the Magellan spacecraft revealed many aeolian features on the planet's surface. While much work has focused on terrestrial wind streaks, the harsh environment of Venus limits direct measurement of surface properties, such as aerodynamic roughness, that affect aeolian features on that planet. However, a correlation between radar backscatter and aerodynamic roughness (Z0) for the S-band radar system on Magellan can be used to study the aerodynamic roughnesses of areas in which Venusian wind streaks occur. The aerodynamic roughness of areas with both radar-bright and radar-dark wind streaks near Mead crater are calculated and compared to z0 values measured on Earth in order to compare the surface of Venus with known terrestrial surface textures.

  19. Vibration Isolation for Parallel Hydraulic Hybrid Vehicles

    Directory of Open Access Journals (Sweden)

    The M. Nguyen

    2008-01-01

    Full Text Available In recent decades, several types of hybrid vehicles have been developed in order to improve the fuel economy and to reduce the pollution. Hybrid electric vehicles (HEV have shown a significant improvement in fuel efficiency for small and medium-sized passenger vehicles and SUVs. HEV has several limitations when applied to heavy vehicles; one is that larger vehicles demand more power, which requires significantly larger battery capacities. As an alternative solution, hydraulic hybrid technology has been found effective for heavy duty vehicle because of its high power density. The mechanical batteries used in hydraulic hybrid vehicles (HHV can be charged and discharged remarkably faster than chemical batteries. This feature is essential for heavy vehicle hybridization. One of the main problems that should be solved for the successful commercialization of HHV is the excessive noise and vibration involving with the hydraulic systems. This study focuses on using magnetorheological (MR technology to reduce the noise and vibration transmissibility from the hydraulic system to the vehicle body. In order to study the noise and vibration of HHV, a hydraulic hybrid subsystem in parallel design is analyzed. This research shows that the MR elements play an important role in reducing the transmitted noise and vibration to the vehicle body. Additionally, locations and orientations of the isolation system also affect the efficiency of the noise and vibration mitigation. In simulations, a skyhook control algorithm is used to achieve the highest possible effectiveness of the MR isolation system.

  20. Some suggested approaches to solving the Hamilton-Jacobi equation associated with constrained rigid body motion

    Science.gov (United States)

    Fitzpatrick, P. M.; Harmon, G. R.; Cochran, J. E.; Shaw, W. A.

    1974-01-01

    Some methods of approaching a solution to the Hamilton-Jacobi equation are outlined and examples are given to illustrate particular methods. These methods may be used for cases where the Hamilton-Jacobi equation is not separable and have been particularly useful in solving the rigid body motion of an earth satellite subjected to gravity torques. These general applications may also have usefulness in studying the motion of satellites with aerodynamic torque and in studying space vehicle motion where thrusting is involved.

  1. The Novel Application of Optimization and Charge Blended Energy Management Control for Component Downsizing within a Plug-in Hybrid Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Ravi Shankar

    2012-11-01

    Full Text Available  The adoption of Plug-in Hybrid Electric Vehicles (PHEVs is widely seen as an interim solution for the decarbonization of the transport sector. Within a PHEV, determining the required energy storage capacity of the battery remains one of the primary concerns for vehicle manufacturers and system integrators. This fact is particularly pertinent since the battery constitutes the largest contributor to vehicle mass. Furthermore, the financial cost associated with the procurement, design and integration of battery systems is often cited as one of the main barriers to vehicle commercialization. The ability to integrate the optimization of the energy management control system with the sizing of key PHEV powertrain components presents a significant area of research. Contained within this paper is an optimization study in which a charge blended strategy is used to facilitate the downsizing of the electrical machine, the internal combustion engine and the high voltage battery. An improved Equivalent Consumption Method has been used to manage the optimal power split within the powertrain as the PHEV traverses a range of different drivecycles. For a target CO2 value and drivecycle, results show that this approach can yield significant downsizing opportunities, with cost reductions on the order of 2%–9% being realizable.

  2. Functional model of the car body for optimisation of the vibration characteristics of a vehicle; Funktionsmodell der Karosserie zur Auslegung des Schwingungskomforts im Gesamtfahrzeug

    Energy Technology Data Exchange (ETDEWEB)

    Spickenreuther, M.

    2006-07-01

    Increasing demands in terms of quality, cost and development time of a new vehicle require new methods of development. Integration of the dynamic car body characteristics by means of a functional car body model already in the conception phase is an important element. Starting from a discussion of possible approaches to defining a functional model, a method based on multibody simulation is developed and applied. Various different strategies for arriving at the required parameters are implemented and presented in detail. The method is tested by verification, and its potential is illustrated by various possible applications. (orig.)

  3. Multi-Mission Earth Vehicle Subsonic Dynamic Stability Testing and Analyses

    Science.gov (United States)

    Glaab, Louis J.; Fremaux, C. Michael

    2013-01-01

    Multi-Mission Earth Entry Vehicles (MMEEVs) are blunt-body vehicles designed with the purpose of transporting payloads from outer space to the surface of the Earth. To achieve high-reliability and minimum weight, MMEEVs avoid use of limited-reliability systems, such as parachutes, retro-rockets, and reaction control systems and rely on the natural aerodynamic stability of the vehicle throughout the Entry, Descent, and Landing (EDL) phase of flight. The Multi-Mission Systems Analysis for Planetary Entry (M-SAPE) parametric design tool is used to facilitate the design of MMEEVs for an array of missions and develop and visualize the trade space. Testing in NASA Langley?s Vertical Spin Tunnel (VST) was conducted to significantly improve M-SAPE?s subsonic aerodynamic models. Vehicle size and shape can be driven by entry flight path angle and speed, thermal protection system performance, terminal velocity limitations, payload mass and density, among other design parameters. The objectives of the VST testing were to define usable subsonic center of gravity limits, and aerodynamic parameters for 6-degree-of-freedom (6-DOF) simulations, for a range of MMEEV designs. The range of MMEEVs tested was from 1.8m down to 1.2m diameter. A backshell extender provided the ability to test a design with a much larger payload for the 1.2m MMEEV.

  4. Subchronic and mild social defeat stress accelerates food intake and body weight gain with polydipsia-like features in mice.

    Science.gov (United States)

    Goto, Tatsuhiko; Kubota, Yoshifumi; Tanaka, Yuki; Iio, Wataru; Moriya, Naoko; Toyoda, Atsushi

    2014-08-15

    Development and characterization of animal models of depression are essential for fully understanding the pathogenesis of depression in humans. We made and analyzed a mouse model exhibiting social deficit and hyperphagia-like behavior using a subchronic and mild social defeat stress (sCSDS) paradigm. The body weight, food and water intake of mice were monitored during a test period, and their behaviors and serum components were analyzed at two stages: immediately after the sCSDS period and 1 month after the sCSDS. The body weight and food intake of defeated mice were significantly higher than control mice at the sCSDS period, and these differences were sustained until 1 month after the sCSDS, whereas the water intake of defeated mice was significantly higher than control mice for the period of sCSDS only. Behavioral analyses revealed that the defeated mice exhibit significant social aversion to unfamiliar mice in a social interaction test and a trend of anxiety-like behavior in an elevated-plus maze test. Possibly due to polydipsia-like symptoms, defeated mice had significantly lower levels of albumin and blood urea nitrogen than control mice immediately after the sCSDS period but not at 1 month after sCSDS. The present study revealed that our sCSDS mice keep much more water in their body than control mice. This study reports the first step toward an understanding of the mechanisms of stress-induced overhydration, over-eating and resultant weight gain.

  5. Features of objectified body consciousness and sociocultural perspectives as risk factors for disordered eating among late-adolescent women and men.

    Science.gov (United States)

    Jackson, Todd; Chen, Hong

    2015-10-01

    Body surveillance and body shame are features of objectified body consciousness (OBC) that have been linked to disordered eating, yet the evidence base is largely cross-sectional and limited to samples in certain Western countries. Furthermore, it is not clear whether these factors contribute to the prediction of eating disturbances independent of conceptually related risk factors emphasized within other sociocultural accounts. In this prospective study, body surveillance, body shame, and features of complementary sociocultural models (i.e., perceived appearance pressure from mass media and close interpersonal networks, appearance social comparisons, negative affect, body dissatisfaction) were assessed as risk factors for and concomitants of eating disturbances over time. University-age, mainland Chinese women (n = 2144) and men (n = 1017) completed validated measures of eating-disorder pathology and hypothesized risk factors at baseline (T1) and 1-year follow-up (T2). Among women, elevations on T1 measures of sociocultural-model features predicted more T2 eating disturbances, independent of T1 disturbances. After controlling for other T1 predictors, body surveillance and shame made modest unique contributions to the model. Finally, heightened T2 body dissatisfaction, media, and interpersonal appearance pressure, negative affect, and body shame predicted concomitant increases in T2 eating concerns. For men, T1 features of sociocultural accounts (negative affect, body dissatisfaction) but not OBC predicted T2 eating disturbances, along with attendant elevations in T2 negative affect, interpersonal appearance pressure, and body shame. Implications are discussed for theory and intervention that target disordered eating. PMID:26191981

  6. In-situ electric field in human body model in different postures for wireless power transfer system in an electrical vehicle

    International Nuclear Information System (INIS)

    The in-situ electric field of an adult male model in different postures is evaluated for exposure to the magnetic field leaked from a wireless power transfer system in an electrical vehicle. The transfer system is located below the centre of the vehicle body and the transferred power and frequency are 7 kW and 85 kHz, respectively. The in-situ electric field is evaluated for a human model (i) crouching near the vehicle, (ii) lying on the ground with or without his arm stretched, (iii) sitting in the driver’s seat, and (iv) standing on a transmitting coil without a receiving coil. In each scenario, the maximum in-situ electric fields are lower than the allowable limit prescribed by international guidelines, although the local magnetic field strength in regions of the human body is higher than the allowable external magnetic field strength. The highest in-situ electric field is observed when the human body model is placed on the ground with his arm extended toward the coils, because of a higher magnetic field around the arm. (paper)

  7. In-situ electric field in human body model in different postures for wireless power transfer system in an electrical vehicle.

    Science.gov (United States)

    Shimamoto, Takuya; Laakso, Ilkka; Hirata, Akimasa

    2015-01-01

    The in-situ electric field of an adult male model in different postures is evaluated for exposure to the magnetic field leaked from a wireless power transfer system in an electrical vehicle. The transfer system is located below the centre of the vehicle body and the transferred power and frequency are 7 kW and 85 kHz, respectively. The in-situ electric field is evaluated for a human model (i) crouching near the vehicle, (ii) lying on the ground with or without his arm stretched, (iii) sitting in the driver's seat, and (iv) standing on a transmitting coil without a receiving coil. In each scenario, the maximum in-situ electric fields are lower than the allowable limit prescribed by international guidelines, although the local magnetic field strength in regions of the human body is higher than the allowable external magnetic field strength. The highest in-situ electric field is observed when the human body model is placed on the ground with his arm extended toward the coils, because of a higher magnetic field around the arm.

  8. The Tanita SC-240 to Assess Body Composition in Pre-School Children: An Evaluation against the Three Component Model.

    Science.gov (United States)

    Delisle Nyström, Christine; Henriksson, Pontus; Alexandrou, Christina; Löf, Marie

    2016-01-01

    Quick, easy-to-use, and valid body composition measurement options for young children are needed. Therefore, we evaluated the ability of the bioelectrical impedance (BIA) device, Tanita SC-240, to measure fat mass (FM), fat free mass (FFM) and body fatness (BF%) in 40 healthy, Swedish 5.5 years old children against the three component model (3C model). Average BF%, FM, and FFM for BIA were: 19.4% ± 3.9%, 4.1 ± 1.9 kg, and 16.4 ± 2.4 kg and were all significantly different (p FFM between BIA and the 3C model. When dividing the children into tertiles for BF%, 60% of children were classified correctly by means of BIA. In conclusion, the Tanita SC-240 underestimated BF% in comparison to the 3C model and had wide limits of agreement. Further work is needed in order to find accurate and easy-to-use methods for assessing body composition in pre-school children. PMID:27322313

  9. 75 FR 49945 - In the Matter of Certain Hybrid Electric Vehicles and Components Thereof; Notice of Commission...

    Science.gov (United States)

    2010-08-16

    ... Paice LLC (``Paice'') of Bonita Springs, Florida. 74 FR. 52258-59 (Oct. 9, 2009). The complaint named as respondents Toyota Motor Corporation of Japan and two U.S. subsidiaries (collectively ``Toyota''). The complaint alleges infringement by certain Toyota hybrid vehicles of claims of U.S. Patent No. 5,343,970....

  10. Management status of end-of-life vehicles and development strategies of used automotive electronic control components recycling industry in China.

    Science.gov (United States)

    Wang, Junjun; Chen, Ming

    2012-11-01

    Recycling companies play a leading role in the system of end-of-life vehicles (ELVs) in China. Automotive manufacturers in China are rarely involved in recycling ELVs, and they seldom provide dismantling information for recycling companies. In addition, no professional shredding plant is available. The used automotive electronic control components recycling industry in China has yet to take shape because of the lack of supporting technology and profitable models. Given the rapid growth of the vehicle population and electronic control units in automotives in China, the used automotive electronic control components recycling industry requires immediate development. This paper analyses the current recycling system of ELVs in China and introduces the automotive product recycling technology roadmap as well as the recycling industry development goals. The strengths, weaknesses, opportunities and challenges of the current used automotive electronic control components recycling industry in China are analysed comprehensively based on the 'strengths, weaknesses, opportunities and threats' (SWOT) method. The results of the analysis indicate that this recycling industry responds well to all the factors and has good opportunities for development. Based on the analysis, new development strategies for the used automotive electronic control components recycling industry in accordance with the actual conditions of China are presented. PMID:22843351

  11. Prevalence of metabolic syndrome and its components among Chinese professional athletes of strength sports with different body weight categories.

    Directory of Open Access Journals (Sweden)

    Jianjun Guo

    Full Text Available BACKGROUND: There is an increasing concern on cardiometabolic health in young professional athletes at heavy-weight class. OBJECTIVE: Our cross-sectional survey aimed to evaluate the prevalence of metabolic syndrome and clustering of metabolic risk factors in a population of young and active professional athletes of strength sports in China. METHODS: From July 2006 to December 2008, a total of 131 male and 130 female athletes of strength sports were enrolled. We used two criteria provided by the Chinese Diabetes Society (2004 and the National Cholesterol Education Program's Adult Treatment Panel III (2002 to define the metabolic syndrome and its individual components, respectively. RESULTS: Regardless of their similar ages (mean: 21 years and exercise levels, athletes in the heaviest-weight-class with unlimited maximum body weight (UBW boundaries (mean weight and BMI: 130 kg and 38 kg/m(2 for men, 110 kg and 37 kg/m(2 for women had significantly higher prevalence of metabolic syndrome than did those in all other body-weight-class with limited body weight (LBW boundaries (mean weight and BMI: 105 kg and 32 kg/m(2 for men, 70 kg and 26 kg/m(2 for women. Prevalence of metabolic syndrome using CDS criteria (UBW vs. LBW: 89% vs. 18% for men, 47% vs. 0% for women and its individual components, including central obesity, hypertension, hypertriglyceridemia, low high-density lipoprotein-cholesterol levels, and impaired fasting glucose, were all significantly higher in athletes at the heaviest weight group with UBW than all other weight groups with LBW. CONCLUSIONS: Our study suggests that professional athletes of strength sports at the heaviest-weight-class are at a significant increased risk of cardiometabolic disease compared with those at all other weight categories. The findings support the importance of developing and implementing the strategy of early screening, awareness, and interventions for weight-related health among young athletes.

  12. Aerodynamic structures and processes in rotationally augmented flow fields

    DEFF Research Database (Denmark)

    Schreck, S.J.; Sørensen, Niels N.; Robinson, M.C.

    2007-01-01

    Rotational augmentation of horizontal axis wind turbine blade aerodynamics currently remains incompletely characterized and understood. To address this, the present study concurrently analysed experimental measurements and computational predictions, both of which were unique and of high quality...... to reliably identify and track pertinent features in the rotating blade boundary layer topology as they evolved in response to varying wind speed. Subsequently, boundary layer state was linked to above-surface flow field structure and used to deduce mechanisms; underlying augmented aerodynamic force...

  13. Aerodynamics of an Axisymmetric Missile Concept Having Cruciform Strakes and In-Line Tail Fins From Mach 0.60 to 4.63, Supplement

    Science.gov (United States)

    Allen, Jerry M.

    2005-01-01

    An experimental study has been performed to develop a large force and moment aerodynamic data set on a slender axisymmetric missile configuration having cruciform strakes and in-line control tail fins. The data include six-component balance measurements of the configuration aerodynamics and three-component measurements on all four tail fins. The test variables include angle of attack, roll angle, Mach number, model buildup, strake length, nose size, and tail fin deflection angles to provide pitch, yaw, and roll control. Test Mach numbers ranged from 0.60 to 4.63. The entire data set is presented on a CD-ROM that is attached to this paper. The CD-ROM also includes extensive plots of both the six-component configuration data and the three-component tail fin data. Selected samples of these plots are presented in this paper to illustrate the features of the data and to investigate the effects of the test variables.

  14. Characterization of magnetized ore bodies based on three-component borehole magnetic and directional borehole seismic measurements

    Science.gov (United States)

    Virgil, Christopher; Neuhaus, Martin; Hördt, Andreas; Giese, Rüdiger; Krüger, Kay; Jurczyk, Andreas; Juhlin, Christopher; Juhojuntti, Niklas

    2016-04-01

    In the last decades magnetic prospecting using total field data was used with great success for localization and characterization of ferromagnetic ore bodies. Especially borehole magnetic measurements reveal important constraints on the extent and depth of potential mining targets. However, due to the inherent ambiguity of the interpretation of magnetic data, the resulting models of the distribution of magnetized material, such as iron ore bodies, are not entirely reliable. Variations in derived parameters like volume and estimated ore content of the expected body have significant impact on the economic efficiency of a planned mine. An important improvement is the introduction of three-component borehole magnetic sondes. Modern tools comprise orientation modules which allow the continuous determination of the tool's heading regardless of the well inclination and independent of the magnetic field. Using the heading information the recorded three-component magnetic data can be transferred from the internal tool's frame to the geographic reference frame. The vector information yields a more detailed and reliable description of the ore bodies compared to total field or horizontal and vertical field data. Nevertheless complementary information to constrain the model is still advisable. The most important supplementary information for the interpretation of magnetic data is the knowledge of the structural environment of the target regions. By discriminating dissimilar rock units, a geometrical starting model can be derived, constraining the magnetic interpretation and leading to a more robust estimation of the rock magnetizations distribution. The most common approach to reveal the lithological setting rests upon seismic measurements. However, for deep drilling targets surface seismic and VSP lack the required spatial resolution of 10s of meters. A better resolution is achieved by using directed sources and receivers inside the borehole. Here we present the application of

  15. CLASSIFICATION OF URBAN FEATURE FROM UNMANNED AERIAL VEHICLE IMAGES USING GASVM INTEGRATION AND MULTI-SCALE SEGMENTATION

    Directory of Open Access Journals (Sweden)

    M. Modiri

    2015-12-01

    Full Text Available The use of UAV in the application of photogrammetry to obtain cover images and achieve the main objectives of the photogrammetric mapping has been a boom in the region. The images taken from REGGIOLO region in the province of, Italy Reggio -Emilia by UAV with non-metric camera Canon Ixus and with an average height of 139.42 meters were used to classify urban feature. Using the software provided SURE and cover images of the study area, to produce dense point cloud, DSM and Artvqvtv spatial resolution of 10 cm was prepared. DTM area using Adaptive TIN filtering algorithm was developed. NDSM area was prepared with using the difference between DSM and DTM and a separate features in the image stack. In order to extract features, using simultaneous occurrence matrix features mean, variance, homogeneity, contrast, dissimilarity, entropy, second moment, and correlation for each of the RGB band image was used Orthophoto area. Classes used to classify urban problems, including buildings, trees and tall vegetation, grass and vegetation short, paved road and is impervious surfaces. Class consists of impervious surfaces such as pavement conditions, the cement, the car, the roof is stored. In order to pixel-based classification and selection of optimal features of classification was GASVM pixel basis. In order to achieve the classification results with higher accuracy and spectral composition informations, texture, and shape conceptual image featureOrthophoto area was fencing. The segmentation of multi-scale segmentation method was used.it belonged class. Search results using the proposed classification of urban feature, suggests the suitability of this method of classification complications UAV is a city using images. The overall accuracy and kappa coefficient method proposed in this study, respectively, 47/93% and 84/91% was.

  16. Computer Aided Aerodynamic Design of Missile Configuration

    Directory of Open Access Journals (Sweden)

    S. Panneerselvam

    1987-10-01

    Full Text Available Aerodynamic configurations of tactical missiles have to produce the required lateral force with minimum time lag to meet the required manoeuvability and response time. The present design which is mainly based on linearised potential flow involves (a indentification of critical design points, (b design of lifting components and their integration with mutual interference, (c evaluation of aerodynamic characteristics, (d checking its adequacy at otherpoints, (e optimization of parameters and selection of configuration, and (f detailed evaluation including aerodynamic pressure distribution. Iterative design process in involed because of the mutual dependance between aerodynamic charactertistics and the parameters of the configuration. though this design method is based on third level of approximation with respect to real flow, aid of computer is essential for carrying out the iterative design process and also for effective selection of configuration by analysing performance. Futuristic design requirement which demand better accuracy on design and estimation calls for sophisticated super computer based theoretical methods viz. , full Euler solution/Navier-Strokes solutions.

  17. Aerodynamics of Wind Turbines

    DEFF Research Database (Denmark)

    Hansen, Martin Otto Laver

    Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its second edition, it has been entirely updated and substantially extended to reflect advances in technology, research into rotor aerodynamics and the structural...... response of the wind turbine structure. Topics covered include increasing mass flow through the turbine, performance at low and high wind speeds, assessment of the extreme conditions under which the turbine will perform and the theory for calculating the lifetime of the turbine. The classical Blade Element...... Momentum method is also covered, as are eigenmodes and the dynamic behavior of a turbine. The new material includes a description of the effects of the dynamics and how this can be modeled in an aeroelastic code, which is widely used in the design and verification of modern wind turbines. Further...

  18. Computational electromagnetic-aerodynamics

    CERN Document Server

    Shang, Joseph J S

    2016-01-01

    Presents numerical algorithms, procedures, and techniques required to solve engineering problems relating to the interactions between electromagnetic fields, fluid flow, and interdisciplinary technology for aerodynamics, electromagnetics, chemical-physics kinetics, and plasmadynamics This book addresses modeling and simulation science and technology for studying ionized gas phenomena in engineering applications. Computational Electromagnetic-Aerodynamics is organized into ten chapters. Chapter one to three introduce the fundamental concepts of plasmadynamics, chemical-physics of ionization, classical magnetohydrodynamics, and their extensions to plasma-based flow control actuators, high-speed flows of interplanetary re-entry, and ion thrusters in space exploration. Chapter four to six explain numerical algorithms and procedures for solving Maxwell’s equation in the time domain for computational electromagnetics, plasma wave propagation, and the time-dependent c mpressible Navier-Stokes equation for aerodyn...

  19. Corrosion Resistance Experiment of a Vehicle Body%某汽车车身耐腐蚀性试验

    Institute of Scientific and Technical Information of China (English)

    冯昌川; 丰刚磊; 宋庆源

    2015-01-01

    为验证某皮卡车型的防腐蚀性能,对该车进行了60个循环的整车强化腐蚀试验,分析了镀锌板、结构设计、打胶工艺对车身防腐蚀性能的影响。结果表明,镀锌板的防腐蚀性能明显优于非镀锌板,相同厚度的热镀锌板和电镀锌板的防腐蚀性能相当;A 柱与翼子板间夹缝宽度小于0.1 mm 时,容易产生腐蚀,而当夹缝宽度大于0.2 mm时,则可以避免锈蚀现象;在钢板搭接位置适量涂覆焊缝密封胶,可保证6个腐蚀年(60个循环试验)不会出现腐蚀问题。本工作对各种腐蚀模态作了试验及理论的探索。%A 60-cycle vehicle accelerated corrosion test was performed to verify the corrosion performance of a pickup.And the effects of different body structures,glue process and galvanized sheet on the corrosion resistance were investigated.The results showed that corrosion resistance of galvanized sheet was better than that of non galvanized sheet,and there was no difference between hot dip galvanized sheet and galvanized sheet when the thickness was the same.Corrosion was more likely to occur when the gap between A-pillar and front wing was smaller than 0.1 mm,but corrosion could be avoided when the gap was larger than 0.2 mm.Appropriate amount of PVC sealant must be applied to welding seams to ensure sufficient corrosion resistance for 6 corrosion test years (60-cycle test).All the above corrosion modes were experimentally studied and theoretically explored in this research.

  20. aerodynamics and heat transfer

    Directory of Open Access Journals (Sweden)

    J. N. Rajadas

    1998-01-01

    Full Text Available A multidisciplinary optimization procedure, with the integration of aerodynamic and heat transfer criteria, has been developed for the design of gas turbine blades. Two different optimization formulations have been used. In the first formulation, the maximum temperature in the blade section is chosen as the objective function to be minimized. An upper bound constraint is imposed on the blade average temperature and a lower bound constraint is imposed on the blade tangential force coefficient. In the second formulation, the blade average and maximum temperatures are chosen as objective functions. In both formulations, bounds are imposed on the velocity gradients at several points along the surface of the airfoil to eliminate leading edge velocity spikes which deteriorate aerodynamic performance. Shape optimization is performed using the blade external and coolant path geometric parameters as design variables. Aerodynamic analysis is performed using a panel code. Heat transfer analysis is performed using the finite element method. A gradient based procedure in conjunction with an approximate analysis technique is used for optimization. The results obtained using both optimization techniques are compared with a reference geometry. Both techniques yield significant improvements with the multiobjective formulation resulting in slightly superior design.

  1. Study on Polarization Spectral Feature of Suspended Sediment in the Water Body%水体悬浮泥沙的偏振光谱特性研究

    Institute of Scientific and Technical Information of China (English)

    朱进; 王先华; 潘邦龙

    2012-01-01

    Remote sensing of lake water based on water-leaving radiance is to retrieve the concentrations of suspended sediment, phytoplankton and yellow substance which have great impacts on spectrum to assess the water quality. Howerver, because of the complexity of the lake water compositons and the interference between the different components, it is of great difficulty to get accurate results with the reflectance spectrum method developed recently. In the present paper, the authors firstly discussed the reflectance and polarization spectral feature of suspended sediment water body, found out the relations of the reflectance and the degree of polarization of water-leaving radiance and the concentration of suspended sediment at the sensitive bands. The authors also compared the effectiveness of the retrieval approaches based on reflectance and polarization in laboratory water body and Chaohu water body respectively. The results show that in the lake water body where the constituents are very complex, the polarization information has greater capacity of anti-jamming, therefore it will have great potential applictions in lake water quality remote sensing.%基于离水辐射的湖泊水体遥感通过反演与光谱关系密切的悬浮泥沙、浮游植物和黄色物质等要素的浓度来实现对水质状况的评估,然而由于湖泊水体的复杂性以及不同要素间的相互干扰,现有的基于反射率光谱的分析方法难以准确反演这些要素.从悬浮泥沙水体离水辐射的反射率、偏振光谱特性出发,给出敏感波段处悬浮泥沙浓度与反射率、偏振度之间的关系,比对了基于反射率以及基于偏振度的两种反演方法在实验室水体、巢湖水体中的应用效果.研究结果表明,在湖泊复杂水体条件下,水体的偏振信息具有比反射率更加良好的抗干扰能力,显示偏振度信息在湖泊水质遥感上存在着重要的应用潜力.

  2. QCD sum rule calculation of quark-gluon three-body components in the B-meson wave function

    Science.gov (United States)

    Nishikawa, Tetsuo; Tanaka, Kazuhiro

    2011-10-01

    We discuss the QCD sum rule calculation of the heavy-quark effective theory parameters λE and λH, which represent quark-gluon three-body components in the B-meson wave function. We update the sum rules for λE,H calculating the new higher-order contributions to the operator product expansion for the corresponding correlator, i.e., the order αs radiative corrections to the Wilson coefficients associated with the dimension-5 quark-gluon mixed condensate, and the power corrections due to the dimension-6 vacuum condensates. We find that the new radiative corrections significantly improve stability of the corresponding Borel sum rules, modifying the values of λE,H.

  3. [Daily calorie and macronutrient consumption in girls of different somatotypes with different shares of body fat, muscle and bone components].

    Science.gov (United States)

    Fefelova, V V; Fefelova, Yu A; Koloskova, T P; Kazakova, T V; Sergeeva, E Yu

    2016-01-01

    211 practically healthy girls, the students of Krasnoyarsk Medical University in the ages of 16 to 20 years, have been examined. We determined their somatotypes (euriplastic, athletic, subathletic and stenoplastic) and body composition (fat, muscle, bone component). Actual nutrition in these subjects was studied by the method. of 24-hour nutrition recall involving foodstuffs models. Energy consumption in cohorts with different somatotypes did not differ from one another and ranged from 1880 to 2115 kilocalories per day, that corresponded to normal physiological needs in women of this age with the coefficient of physical activity as 1.4 (students). Only the intake of fat (% of calories) exceeded the performance standards. As for macronutrients, the majority of indicators of nutrient intake did not differ significantly among girls with different somatotype, except for fat intake in girls with athletic and stenoplastic somatotypes (pdistribution of substrate flow among cell metabolic paths, appropriate of definite somatotypes. PMID:27455598

  4. Fairing Well: Aerodynamic Truck Research at NASA Dryden Flight Research Center. From Shoebox to Bat Truck and Beyond

    Science.gov (United States)

    Gelzer, Christian

    2011-01-01

    In 1973 engineers at Dryden began investigating ways to reduce aerodynamic drag on land vehicles. They began with a delivery van whose shape they changed dramatically, finally reducing its aerodynamic drag by more than 5 percent. They then turned their attention to tracator-trailers, modifying a cab-over and reducing its aerodynamic drag by nearly 25 percent. Further research identified additional areas worth attention, but in the intervening decades few of those changes have appeared.

  5. Development of an Aerodynamic Analysis Method and Database for the SLS Service Module Panel Jettison Event Utilizing Inviscid CFD and MATLAB

    Science.gov (United States)

    Applebaum, Michael P.; Hall, Leslie, H.; Eppard, William M.; Purinton, David C.; Campbell, John R.; Blevins, John A.

    2015-01-01

    This paper describes the development, testing, and utilization of an aerodynamic force and moment database for the Space Launch System (SLS) Service Module (SM) panel jettison event. The database is a combination of inviscid Computational Fluid Dynamic (CFD) data and MATLAB code written to query the data at input values of vehicle/SM panel parameters and return the aerodynamic force and moment coefficients of the panels as they are jettisoned from the vehicle. The database encompasses over 5000 CFD simulations with the panels either in the initial stages of separation where they are hinged to the vehicle, in close proximity to the vehicle, or far enough from the vehicle that body interference effects are neglected. A series of viscous CFD check cases were performed to assess the accuracy of the Euler solutions for this class of problem and good agreement was obtained. The ultimate goal of the panel jettison database was to create a tool that could be coupled with any 6-Degree-Of-Freedom (DOF) dynamics model to rapidly predict SM panel separation from the SLS vehicle in a quasi-unsteady manner. Results are presented for panel jettison simulations that utilize the database at various SLS flight conditions. These results compare favorably to an approach that directly couples a 6-DOF model with the Cart3D Euler flow solver and obtains solutions for the panels at exact locations. This paper demonstrates a method of using inviscid CFD simulations coupled with a 6-DOF model that provides adequate fidelity to capture the physics of this complex multiple moving-body panel separation event.

  6. Freight Wing Trailer Aerodynamics Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Sean Graham

    2007-10-31

    Freight Wing Incorporated utilized the opportunity presented by a DOE category two Inventions and Innovations grant to commercialize and improve upon aerodynamic technology for semi-tuck trailers, capable of decreasing heavy vehicle fuel consumption, related environmental damage, and U.S. consumption of foreign oil. Major project goals included the demonstration of aerodynamic trailer technology in trucking fleet operations, and the development and testing of second generation products. A great deal of past scientific research has demonstrated that streamlining box shaped semi-trailers can significantly reduce a truck’s fuel consumption. However, significant design challenges have prevented past concepts from meeting industry needs. Freight Wing utilized a 2003 category one Inventions and Innovations grant to develop practical solutions to trailer aerodynamics. Fairings developed for the front, rear, and bottom of standard semi-trailers together demonstrated a 7% improvement to fuel economy in scientific tests conducted by the Transportation Research Center (TRC). Operational tests with major trucking fleets proved the functionality of the products, which were subsequently brought to market. This category two grant enabled Freight Wing to further develop, test and commercialize its products, resulting in greatly increased understanding and acceptance of aerodynamic trailer technology. Commercialization was stimulated by offering trucking fleets 50% cost sharing on trial implementations of Freight Wing products for testing and evaluation purposes. Over 230 fairings were implemented through the program with 35 trucking fleets including industry leaders such as Wal-Mart, Frito Lay and Whole Foods. The feedback from these testing partnerships was quite positive with product performance exceeding fleet expectations in many cases. Fleet feedback also was also valuable from a product development standpoint and assisted the design of several second generation products

  7. Vortical sources of aerodynamic force and moment

    Science.gov (United States)

    Wu, J. Z.; Wu, J. M.

    1989-01-01

    It is shown that the aerodynamic force and moment can be expressed in terms of vorticity distribution (and entropy variation for compressible flow) on near wake plane, or in terms of boundary vorticity flux on the body surface. Thus the vortical sources of lift and drag are clearly identified, which is the real physical basis of optimal aerodynamic design. Moreover, these sources are highly compact, hence allowing one to concentrate on key local regions of the configuration, which have dominating effect to the lift and drag. A detail knowledge of the vortical low requires measuring or calculating the vorticity and dilatation field, which is however still a challenging task. Nevertheless, this type of formulation has some unique advantages; and how to set up a well-posed problem, in particular how to establish vorticity-dilatation boundary conditions, is addressed.

  8. Aerodynamics of Rotor Blades for Quadrotors

    CERN Document Server

    Bangura, Moses; Naldi, Roberto; Mahony, Robert

    2016-01-01

    In this report, we present the theory on aerodynamics of quadrotors using the well established momentum and blade element theories. From a robotics perspective, the theoretical development of the models for thrust and horizontal forces and torque (therefore power) are carried out in the body fixed frame of the quadrotor. Using momentum theory, we propose and model the existence of a horizontal force along with its associated power. Given the limitations associated with momentum theory and the inadequacy of the theory to account for the different powers represented in a proposed bond graph lead to the use of blade element theory. Using this theory, models are then developed for the different quadrotor rotor geometries and aerodynamic properties including the optimum hovering rotor used on the majority of quadrotors. Though this rotor is proven to be the most optimum rotor, we show that geometric variations are necessary for manufacturing of the blades. The geometric variations are also dictated by a desired th...

  9. The Aerodynamics of Deforming Wings at Low Reynolds Number

    Science.gov (United States)

    Medina, Albert

    Flapping flight has gained much attention in the past decade driven by the desire to understand capabilities observed in nature and the desire to develop agile small-scale aerial vehicles. Advancing our current understanding of unsteady aerodynamics is an essential component in the development of micro-air vehicles (MAV) intended to utilize flight mechanics akin to insect flight. Thus the efforts undertaken that of bio-mimicry. The complexities of insect wing motion are dissected and simplified to more tractable problems to elucidate the fundamentals of unsteady aerodynamics in biologically inspired kinematics. The MAV's fruition would satisfy long established needs in both the military and civilian sectors. Although recent studies have provided great insight into the lift generating mechanisms of flapping wings the deflection response of such wings remains poorly understood. This dissertation numerically and experimentally investigates the aerodynamic performance of passively and actively deflected wings in hover and rotary kinematics. Flexibility is distilled to discrete lines of flexion which acknowledging major flexion lines in insect wings to be the primary avenue for deformation. Of primary concern is the development of the leading-edge vortex (LEV), a high circulation region of low pressure above the wing to which much of the wing's lift generation is attributed. Two-dimensional simulations of wings with chord-wise flexibility in a freestream reveal a lift generating mechanism unavailable to rigid wings with origins in vortical symmetry breaking. The inclusion of flexibility in translating wings accelerated from rest revealed the formation time of the initial LEV was very weakly dependent on the flexible stiffness of the wing, maintaining a universal time scale of four to five chords of travel before shedding. The frequency of oscillatory shedding of the leading and trailing-edge vortices that develops after the initial vortex shedding was shown to be

  10. Computational aerodynamics of low Reynolds number plunging, pitching and flexible wings for MAV applications

    Institute of Scientific and Technical Information of China (English)

    W. Shyy; P. Ifju; Y. Lian; J. Tang; H. Liu; P. Trizila; B. Stanford; L. Bernal; C. Cesnik; P. Friedmann

    2008-01-01

    Micro air vehicles (MAV's) have the potential to revolutionize our sensing and information gathering capabilities in environmental monitoring and homeland security areas. Due to the MAV's' small size, flight regime, and modes of operation, significant scientific advancement will be needed to create this revolutionary capability.Aerodynamics, structural dynamics, and flight dynamics of natural flyers intersects with some of the richest problems inMAV's, including massively unsteady three-dimensional separation, transition in boundary layers and shear layers, vortical flows and bluff body flows, unsteady flight environment, aeroelasticity, and nonlinear and adaptive control are just a fewexamples.Achallenge is that the scaling of both fluid dynamics and structural dynamics between smaller natural flyer and practical flying hardware/lab experiment (larger dimension) is fundamentally difficult. In this paper, we offer an overview of the challenges and issues, along with sample results illustrating some of the efforts made from a computational modeling angle.

  11. Analysis of Dragonfly Take-off Mechanism: Initial Impulse Generated by Aerodynamic Forces

    Science.gov (United States)

    Zhu, Ruijie; Bode-Oke, Ayodeji; Ren, Yan; Dong, Haibo; Flow Simulation Research Team

    2013-11-01

    Take-off is a critical part of insect flight due to not only that every single flight initiates from take-off, but also that the take-off period, despite its short duration, accounts for a relatively large fraction of the total energy consumption. Thus, studying the mechanism of insect take-off will help to improve the design of Micro Air Vehicles (MAVs) in two major properties, the success rate and the energy efficiency of take-off. In this work, we study 20 cases in which dragonflies (species including Pachydiplax longipennis, Epitheca Cynosura, Epitheca princeps etc.) take off from designed platform. By high-speed photogrammetry, 3-d reconstruction and numerical simulation, we explore how dragonflies coordinate different body parts to help take-off. We evaluate how aerodynamic forces generated by wing flapping create the initial impulse, and how these forces help save energy consumption. Supported by NSF CBET-1343154.

  12. Feasibility study for a numerical aerodynamic simulation facility. Volume 1

    Science.gov (United States)

    Lincoln, N. R.; Bergman, R. O.; Bonstrom, D. B.; Brinkman, T. W.; Chiu, S. H. J.; Green, S. S.; Hansen, S. D.; Klein, D. L.; Krohn, H. E.; Prow, R. P.

    1979-01-01

    A Numerical Aerodynamic Simulation Facility (NASF) was designed for the simulation of fluid flow around three-dimensional bodies, both in wind tunnel environments and in free space. The application of numerical simulation to this field of endeavor promised to yield economies in aerodynamic and aircraft body designs. A model for a NASF/FMP (Flow Model Processor) ensemble using a possible approach to meeting NASF goals is presented. The computer hardware and software are presented, along with the entire design and performance analysis and evaluation.

  13. Impacts of battery characteristics, driver preferences and road network features on travel costs of a plug-in hybrid electric vehicle (PHEV) for long-distance trips

    International Nuclear Information System (INIS)

    In a road network with refueling and fast charging stations, the minimum-cost driving path of a plug-in hybrid electric vehicle (PHEV) depends on factors such as location and availability of refueling/fast charging stations, capacity and cost of PHEV batteries, and driver tolerance towards extra mileage or additional stopping. In this paper, our focus is long-distance trips of PHEVs. We analyze the impacts of battery characteristics, often-overlooked driver preferences and road network features on PHEV travel costs for long-distance trips and compare the results with hybrid electric and conventional vehicles. We investigate the significance of these factors and derive critical managerial insights for shaping the future investment decisions about PHEVs and their infrastructure. In particular, our findings suggest that with a certain level of deployment of fast charging stations, well established cost and emission benefits of PHEVs for the short range trips can be extended to long distance. Drivers' stopping intolerance may hamper these benefits; however, increasing battery capacity may help overcome the adverse effects of this intolerance. - Highlights: • We investigate the travel costs of CVs, HEVs and PHEVs for long-distance trips. • We analyze the impacts of battery, driver and road network characteristics on the costs. • We provide critical managerial insights to shape the investment decisions about PHEVs. • Drivers' stopping intolerance may hamper the cost and emission benefits of PHEVs. • Negative effect of intolerance on cost may be overcome by battery capacity expansion

  14. Comparative Analysis of Uninhibited and Constrained Avian Wing Aerodynamics

    Science.gov (United States)

    Cox, Jordan A.

    The flight of birds has intrigued and motivated man for many years. Bird flight served as the primary inspiration of flying machines developed by Leonardo Da Vinci, Otto Lilienthal, and even the Wright brothers. Avian flight has once again drawn the attention of the scientific community as unmanned aerial vehicles (UAV) are not only becoming more popular, but smaller. Birds are once again influencing the designs of aircraft. Small UAVs operating within flight conditions and low Reynolds numbers common to birds are not yet capable of the high levels of control and agility that birds display with ease. Many researchers believe the potential to improve small UAV performance can be obtained by applying features common to birds such as feathers and flapping flight to small UAVs. Although the effects of feathers on a wing have received some attention, the effects of localized transient feather motion and surface geometry on the flight performance of a wing have been largely overlooked. In this research, the effects of freely moving feathers on a preserved red tailed hawk wing were studied. A series of experiments were conducted to measure the aerodynamic forces on a hawk wing with varying levels of feather movement permitted. Angle of attack and air speed were varied within the natural flight envelope of the hawk. Subsequent identical tests were performed with the feather motion constrained through the use of externally-applied surface treatments. Additional tests involved the study of an absolutely fixed geometry mold-and-cast wing model of the original bird wing. Final tests were also performed after applying surface coatings to the cast wing. High speed videos taken during tests revealed the extent of the feather movement between wing models. Images of the microscopic surface structure of each wing model were analyzed to establish variations in surface geometry between models. Recorded aerodynamic forces were then compared to the known feather motion and surface

  15. Freight Wing Trailer Aerodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Graham, Sean (Primary Investigator); Bigatel, Patrick

    2004-10-17

    Freight Wing Incorporated utilized the opportunity presented by this DOE category one Inventions and Innovations grant to successfully research, develop, test, patent, market, and sell innovative fuel and emissions saving aerodynamic attachments for the trucking industry. A great deal of past scientific research has demonstrated that streamlining box shaped semi-trailers can significantly reduce a truck's fuel consumption. However, significant design challenges have prevented past concepts from meeting industry needs. Market research early in this project revealed the demands of truck fleet operators regarding aerodynamic attachments. Products must not only save fuel, but cannot interfere with the operation of the truck, require significant maintenance, add significant weight, and must be extremely durable. Furthermore, SAE/TMC J1321 tests performed by a respected independent laboratory are necessary for large fleets to even consider purchase. Freight Wing used this information to create a system of three practical aerodynamic attachments for the front, rear and undercarriage of standard semi trailers. SAE/TMC J1321 Type II tests preformed by the Transportation Research Center (TRC) demonstrated a 7% improvement to fuel economy with all three products. If Freight Wing is successful in its continued efforts to gain market penetration, the energy and environmental savings would be considerable. Each truck outfitted saves approximately 1,100 gallons of fuel every 100,000 miles, which prevents over 12 tons of CO2 from entering the atmosphere. If all applicable trailers used the technology, the country could save approximately 1.8 billion gallons of diesel fuel, 18 million tons of emissions and 3.6 billion dollars annually.

  16. Location of Body Wave Microseism Sources Using Three-Component Data From a Large Aperture Seismic Array in China

    Science.gov (United States)

    Liu, Q.; Koper, K. D.; Burlacu, R.; Ni, S.; Wang, F.

    2015-12-01

    From September 2013 through October 2014 up to 100 Guralp CMG-3 broadband seismometers were deployed in the WT-Array (WTA) in northwest China. The aperture of WTA is about 700 km, with an average station spacing of approximately 50 km. Here, we process continuous, three-component WTA data to detect and locate body wave microseism sources in four distinct period bands: 1.0-2.5 s, 2.5-5 s, 5-10 s, and 10-20 s. We back-project vertical component data through a 1D reference Earth model (AK135) to a global grid of hypothetical source locations, assuming P-wave (30o-90o), PP-wave (60o-180o), and S-wave (30o-75o) propagation. At the same time, we rotate the horizontals and back-project the radial and transverse components of the wavefield. For each frequency band, grid point, and assumed origin time, the array power is calculated from the amplitude of a windowed, filtered, and tapered time domain beam constructed with fourth-root stacking. We find strong P-wave and S-wave noise sources in the North Pacific and North Atlantic Oceans. Shorter period sources (2.5-5 s) are mainly observed in the North Pacific Ocean, while both short and long period (2.5-20 s) sources are observed in the North Atlantic Ocean. Median power plots for each month during September 2013 through October 2014 show distinct seasonal variations. The energy peaks in the North Atlantic are visible from November to March and strong energy is also observed in the North Pacific from October to April. We also observe PP-waves in the Southern Ocean, especially for May-August 2014. Using classical f-k analysis and plane-wave propagation, we are able to confirm the back-projection results. To improve our understanding of body wave microseism generation, we compare the observed P, S, and PP wave microseism locations with the predictions of significant wave height and wave-wave interactions derived from the WAVEWATCH III ocean model.From September 2013 through October 2014 up to 100 Guralp CMG-3 broadband

  17. Aerodynamics of wind turbines

    CERN Document Server

    Hansen, Martin O L

    2015-01-01

    Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its third edition, it has been substantially updated with respect to structural dynamics and control. The new control chapter now includes details on how to design a classical pitch and torque regulator to control rotational speed and power, while the section on structural dynamics has been extended with a simplified mechanical system explaining the phenomena of forward and backward whirling modes. Readers will also benefit from a new chapter on Vertical Axis W

  18. Sensor Systems Collect Critical Aerodynamics Data

    Science.gov (United States)

    2010-01-01

    With the support of Small Business Innovation Research (SBIR) contracts with Dryden Flight Research Center, Tao of Systems Integration Inc. developed sensors and other components that will ultimately form a first-of-its-kind, closed-loop system for detecting, measuring, and controlling aerodynamic forces and moments in flight. The Hampton, Virginia-based company commercialized three of the four planned components, which provide sensing solutions for customers such as Boeing, General Electric, and BMW and are used for applications such as improving wind turbine operation and optimizing air flow from air conditioning systems. The completed system may one day enable flexible-wing aircraft with flight capabilities like those of birds.

  19. Wavelet low- and high-frequency components as features for predicting stock prices with backpropagation neural networks

    OpenAIRE

    Salim Lahmiri

    2014-01-01

    This paper presents a forecasting model that integrates the discrete wavelet transform (DWT) and backpropagation neural networks (BPNN) for predicting financial time series. The presented model first uses the DWT to decompose the financial time series data. Then, the obtained approximation (low-frequency) and detail (high-frequency) components after decomposition of the original time series are used as input variables to forecast future stock prices. Indeed, while high-frequency components ca...

  20. Wavelet low- and high-frequency components as features for predicting stock prices with backpropagation neural networks

    Directory of Open Access Journals (Sweden)

    Salim Lahmiri

    2014-07-01

    Full Text Available This paper presents a forecasting model that integrates the discrete wavelet transform (DWT and backpropagation neural networks (BPNN for predicting financial time series. The presented model first uses the DWT to decompose the financial time series data. Then, the obtained approximation (low-frequency and detail (high-frequency components after decomposition of the original time series are used as input variables to forecast future stock prices. Indeed, while high-frequency components can capture discontinuities, ruptures and singularities in the original data, low-frequency components characterize the coarse structure of the data, to identify the long-term trends in the original data. As a result, high-frequency components act as a complementary part of low-frequency components. The model was applied to seven datasets. For all of the datasets, accuracy measures showed that the presented model outperforms a conventional model that uses only low-frequency components. In addition, the presented model outperforms both the well-known auto-regressive moving-average (ARMA model and the random walk (RW process.

  1. The Aerodynamic Plane Table

    Science.gov (United States)

    Zahm, A F

    1924-01-01

    This report gives the description and the use of a specially designed aerodynamic plane table. For the accurate and expeditious geometrical measurement of models in an aerodynamic laboratory, and for miscellaneous truing operations, there is frequent need for a specially equipped plan table. For example, one may have to measure truly to 0.001 inch the offsets of an airfoil at many parts of its surface. Or the offsets of a strut, airship hull, or other carefully formed figure may require exact calipering. Again, a complete airplane model may have to be adjusted for correct incidence at all parts of its surfaces or verified in those parts for conformance to specifications. Such work, if but occasional, may be done on a planing or milling machine; but if frequent, justifies the provision of a special table. For this reason it was found desirable in 1918 to make the table described in this report and to equip it with such gauges and measures as the work should require.

  2. Aerodynamics of sports balls

    Science.gov (United States)

    Mehta, R. D.

    1985-01-01

    Research data on the aerodynamic behavior of baseballs and cricket and golf balls are summarized. Cricket balls and baseballs are roughly the same size and mass but have different stitch patterns. Both are thrown to follow paths that avoid a batter's swing, paths that can curve if aerodynamic forces on the balls' surfaces are asymmetric. Smoke tracer wind tunnel tests and pressure taps have revealed that the unbalanced side forces are induced by tripping the boundary layer on the seam side and producing turbulence. More particularly, the greater pressures are perpendicular to the seam plane and only appear when the balls travel at velocities high enough so that the roughness length matches the seam heigh. The side forces, once tripped, will increase with spin velocity up to a cut-off point. The enhanced lift coefficient is produced by the Magnus effect. The more complex stitching on a baseball permits greater variations in the flight path curve and, in the case of a knuckleball, the unsteady flow effects. For golf balls, the dimples trip the boundary layer and the high spin rate produces a lift coefficient maximum of 0.5, compared to a baseball's maximum of 0.3. Thus, a golf ball travels far enough for gravitational forces to become important.

  3. Aerodynamics of sports balls

    Science.gov (United States)

    Mehta, R. D.

    Research data on the aerodynamic behavior of baseballs and cricket and golf balls are summarized. Cricket balls and baseballs are roughly the same size and mass but have different stitch patterns. Both are thrown to follow paths that avoid a batter's swing, paths that can curve if aerodynamic forces on the balls' surfaces are asymmetric. Smoke tracer wind tunnel tests and pressure taps have revealed that the unbalanced side forces are induced by tripping the boundary layer on the seam side and producing turbulence. More particularly, the greater pressures are perpendicular to the seam plane and only appear when the balls travel at velocities high enough so that the roughness length matches the seam heigh. The side forces, once tripped, will increase with spin velocity up to a cut-off point. The enhanced lift coefficient is produced by the Magnus effect. The more complex stitching on a baseball permits greater variations in the flight path curve and, in the case of a knuckleball, the unsteady flow effects. For golf balls, the dimples trip the boundary layer and the high spin rate produces a lift coefficient maximum of 0.5, compared to a baseball's maximum of 0.3. Thus, a golf ball travels far enough for gravitational forces to become important.

  4. A program to compute three-dimensional subsonic unsteady aerodynamic characteristics using the doublet lattice method, L216 (DUBFLEX). Volume 2: Supplemental system design and maintenance document

    Science.gov (United States)

    Harrison, B. A.; Richard, M.

    1979-01-01

    The information necessary for execution of the digital computer program L216 on the CDC 6600 is described. L216 characteristics are based on the doublet lattice method. Arbitrary aerodynamic configurations may be represented with combinations of nonplanar lifting surfaces composed of finite constant pressure panel elements, and axially summetric slender bodies composed of constant pressure line elements. Program input consists of configuration geometry, aerodynamic parameters, and modal data; output includes element geometry, pressure difference distributions, integrated aerodynamic coefficients, stability derivatives, generalized aerodynamic forces, and aerodynamic influence coefficient matrices. Optionally, modal data may be input on magnetic field (tape or disk), and certain geometric and aerodynamic output may be saved for subsequent use.

  5. A Cosserat-based formulation for elastic, axisymmetric shells with implications to the pulsed-jetting propulsion of soft-bodied aquatic vehicles

    Science.gov (United States)

    Renda, Federico; Giorgio-Serchi, Francesco; Boyer, Frederic

    We take the cue from recent development in geometric-based modelling in order to describe the dynamics of a novel soft-structured aquatic vehicle. The Cosserat-like formulation for an axisymmetric, elastic shell subject to concentrated dynamic loadings lends itself to the case of this new vehicle, recently designed by the authors, which consists of a shell of rubber-like materials undergoing sequential stages of inflation and deflation in order to propel itself in water via pulsed-jetting. The experiments performed on the existing robotic prototypes are used for the validation of the geometric model. This is eventually employed for deriving an accurate measure of the efficiency of propulsion which explicitly accounts for the elastic energy involved during the propulsion routine. The model yields a-priori estimations of swimming efficiency based on vehicle specifications and mode of actuation. These provide invaluable information for both design optimization and control, as well as a means to study the biomechanics of soft-bodied aquatic organisms. Presenting author.

  6. Development history of the Hybrid Test Vehicle

    Science.gov (United States)

    Trummel, M. C.; Burke, A. F.

    1983-01-01

    Phase I of a joint Department of Energy/Jet Propulsion Laboratory Program undertook the development of the Hybrid Test Vehicle (HTV), which has subsequently progressed through design, fabrication, and testing and evaluation phases. Attention is presently given to the design and test experience gained during the HTV development program, and a discussion is presented of the design features and performance capabilities of the various 'mule' vehicles, devoted to the separate development of engine microprocessor control, vehicle structure, and mechanical components, whose elements were incorporated into the final HTV design. Computer projections of the HTV's performance are given.

  7. Molecular sled is an eleven-amino acid vehicle facilitating biochemical interactions via sliding components along DNA.

    Science.gov (United States)

    Mangel, Walter F; McGrath, William J; Xiong, Kan; Graziano, Vito; Blainey, Paul C

    2016-02-02

    Recently, we showed the adenovirus proteinase interacts productively with its protein substrates in vitro and in vivo in nascent virus particles via one-dimensional diffusion along the viral DNA. The mechanism by which this occurs has heretofore been unknown. We show sliding of these proteins along DNA occurs on a new vehicle in molecular biology, a 'molecular sled' named pVIc. This 11-amino acid viral peptide binds to DNA independent of sequence. pVIc slides on DNA, exhibiting the fastest one-dimensional diffusion constant, 26±1.8 × 10(6) (bp)(2) s(-1). pVIc is a 'molecular sled,' because it can slide heterologous cargos along DNA, for example, a streptavidin tetramer. Similar peptides, for example, from the C terminus of β-actin or NLSIII of the p53 protein, slide along DNA. Characteristics of the 'molecular sled' in its milieu (virion, nucleus) have implications for how proteins in the nucleus of cells interact and imply a new form of biochemistry, one-dimensional biochemistry.

  8. Aerodynamic Performances of Corrugated Dragonfly Wings at Low Reynolds Numbers

    Science.gov (United States)

    Tamai, Masatoshi; He, Guowei; Hu, Hui

    2006-11-01

    The cross-sections of dragonfly wings have well-defined corrugated configurations, which seem to be not very suitable for flight according to traditional airfoil design principles. However, previous studies have led to surprising conclusions of that corrugated dragonfly wings would have better aerodynamic performances compared with traditional technical airfoils in the low Reynolds number regime where dragonflies usually fly. Unlike most of the previous studies of either measuring total aerodynamics forces (lift and drag) or conducting qualitative flow visualization, a series of wind tunnel experiments will be conducted in the present study to investigate the aerodynamic performances of corrugated dragonfly wings at low Reynolds numbers quantitatively. In addition to aerodynamics force measurements, detailed Particle Image Velocimetry (PIV) measurements will be conducted to quantify of the flow field around a two-dimensional corrugated dragonfly wing model to elucidate the fundamental physics associated with the flight features and aerodynamic performances of corrugated dragonfly wings. The aerodynamic performances of the dragonfly wing model will be compared with those of a simple flat plate and a NASA low-speed airfoil at low Reynolds numbers.

  9. Body concept quality and precision. Uniform impression of quality; Konzeptqualitaet und Praezision der Karosserie. Wertanmutung aus einem Guss

    Energy Technology Data Exchange (ETDEWEB)

    Trost, W.; Siehler, U.; Tenfelde, H.

    2002-05-01

    The bodyshell performs a central integration function in the overall vehicle system. The goal of development was to bring all requirements and interfaces to major assemblies and equipment components 'under one umbrella'. In addition, the engineers wished to further increase the standards set in this vehicle class in the previous model in disciplines such as structural strength, long-term quality, lightweight design, aerodynamics and - by no means least - safety. The body is additionally characterised by even better noise and vibration comfort, perfect directional stability nd road adhesion and very good repair-friendliness. (orig.) [German] Im System Gesamtfahrzeug erfuellt der Karosserie-Rohbau eine zentrale Integrationsfunktion. Bei der Entwicklung galt es, alle Anforderungen und Schnittstellen zu Aggregaten und Ausstattungsteilen 'unter einen Hut' zu bringen. Zusaetzlich wollten die Ingenieure die bereits beim Vorgaengermodell in wichtigen Disziplinen wie Strukturfestigkeit, Langzeitqualitaet, Leichtbau, Aerodynamik und nicht zuletzt Sicherheit gesetzten Massstaebe noch weiter steigern. Die Karosserie der neuen E-Klasse zeichnet sich ausserdem durch einen noch besseren Geraeusch- und Schwingungskomfort, perfekte Fahrstabilitaet und sehr gute Reparaturfreundlichkeit aus. (orig.)

  10. Differential Features of Cerebral Perfusion in Dementia with Lewy Bodies Compared to Alzheimer's Dementia using SPM Analysis

    International Nuclear Information System (INIS)

    Alzheimer's dementia (AD) and dementia with Lewy bodies (DLB) are most common cause of dementia in elderly people. Clinical distinction in some cases of DLB from AD may be difficult as symptom profiles overlap. Some neuropathologic overlap is also seen as beta-amyloidosis and senile plaques can be found in both disease. Both disease also share severe acetylcholine depletion. We evaluated the differences of brain perfusion between DLB and AD using statistical parametric mapping analysis. Twelve DLB (mean age ; 68.8±8.3 years, K-MMSE ; 17.3±6.1) and 51 AD patients (mean age ; 71.4±7.2 years, K-MMSE ; 16.7±4.5), which were matched for age and severity of dementia, participated in this study. Tc-99m HMPAO SPECT was performed for measuring regional cerebral blood flow. Statistical parametric mapping (SPM99) software was used for automatic and objective approach to analyze SPECT image data. The SPECT data of the patients with DLB were compared to patients with AD. Comparison of the two dementia groups (uncorrected p<0.01) revealed significant hypoperfusion in both occipital (both middle occipital gyrus, Rt B no. 18 and Lt cuneus), both parietal (Lt parietal precuneus, Lt B no. 39, Lt inferior parietal lobule and Rt supramarginal gyrus) lobes in DLB compared with AD. Significant hyperperfusion was noted in Rt frontal (sup. frontal gyrus, B no.10, middle frontal gyrus, B no. 9, B no. 11, inf. frontal gyrus), Rt putamen, Lt ant. cingulate gyrus (B no. 24), both cerebellar post. lobe (Lt tuber, Lt declive, Lt tonsil, Rt declive) in DLB compared with AD. We found a significant differences in the cerebral perfusion pattern between DLB and AD. Differential feature of cerebral perfusion in DLB was both occipital hypoperfusion and preserved Rt frontal perfusion compared to AD. Therefore in difficult case of clinical an neuro pathologic diagnosis, brain perfusion SPECT with SPM analysis may be helpful to differentiate DLB from AD

  11. Aerodynamic characteristics research on wide-speed range waverider configuration

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Waverider generated from a given flow field has a high lift-to-drag ratio because of attached bow shock on leading edge. However, leading edge blunt and off-design condition can make bow shock off leading edge and have unfavorable influence on aerodynamic characteristics. So these two problems have always been concerned as important engineering science issues by aeronautical engineering scientists. In this paper, through respectively using low speed and high speed waverider design principles, a wide-speed rang vehicle is designed, which can level takeoff and accelerate to hypersonic speed for cruise. In addition, sharp leading edge is blunted to alleviated aeroheating. Theoretical study and wind tunnel test show that this vehicle has good aerodynamic performance in wide-speed range of subsonic, transonic, supersonic and hypersonic speeds.

  12. Development of Near Optimal Rule-Based Control for Plug-In Hybrid Electric Vehicles Taking into Account Drivetrain Component Losses

    Directory of Open Access Journals (Sweden)

    Hanho Son

    2016-05-01

    Full Text Available A near-optimal rule-based mode control (RBC strategy was proposed for a target plug-in hybrid electric vehicle (PHEV taking into account the drivetrain losses. Individual loss models were developed for drivetrain components including the gears, planetary gear (PG, bearings, and oil pump, based on experimental data and mathematical governing equations. Also, a loss model for the power electronic system was constructed, including loss from the motor-generator while rotating in the unloaded state. To evaluate the effect of the drivetrain losses on the operating mode control strategy, backward simulations were performed using dynamic programming (DP. DP selects the operating mode, which provides the highest efficiency for given driving conditions. It was found that the operating mode selection changes when drivetrain losses are included, depending on driving conditions. An operating mode schedule was developed with respect to the wheel power and vehicle speed, and based on the operating mode schedule, a RBC was obtained, which can be implemented in an on-line application. To evaluate the performance of the RBC, a forward simulator was constructed for the target PHEV. The simulation results show near-optimal performance of the RBC compared with dynamic-programming-based mode control in terms of the mode operation time and fuel economy. The RBC developed with drivetrain losses taken into account showed a 4%–5% improvement of the fuel economy over a similar RBC, which neglected the drivetrain losses.

  13. Unsteady Aerodynamics of Flapping Wing of a Bird

    Directory of Open Access Journals (Sweden)

    M. Agoes Moelyadi

    2013-04-01

    Full Text Available The unsteady flow behavior and time-dependent aerodynamic characteristics of the flapping motion of a bird’s wing were investigated using a computational method. During flapping, aerodynamic interactions between bird wing surfaces and surrounding flow may occur, generating local time-dependent flow changes in the flow field and aerodynamic load of birds. To study the effect of flapping speed on unsteady aerodynamic load, two kinds of computational simulations were carried out, namely a quasi-steady and an unsteady simulation. To mimic the movement of the down-stroke and the upstroke of a bird, the flapping path accorded to a sinus function, with the wing attitude changing in dihedral angle and time. The computations of time-dependent viscous flow were based on the solution of the Reynolds Averaged Navier-Stokes equations by applying the k-e turbulence model. In addition, the discretization for the computational domain around the model used multi-block structured grid to provide more accuracy in capturing viscous flow, especially in the vicinity of the wing and body surfaces, to obtain a proper wing-body geometry model. For this research, the seagull bird was chosen, which has high aspect ratio wings with pointed wing-tips and a high camber wing section. The results include mesh movement, velocity contours as well as aerodynamic coefficients of the flapping motion of the bird at various flapping frequencies.

  14. A ROBUST GA/KNN BASED HYPOTHESIS VERIFICATION SYSTEM FOR VEHICLE DETECTION

    Directory of Open Access Journals (Sweden)

    Nima Khairdoost

    2015-03-01

    Full Text Available Vehicle detection is an important issue in driver assistance systems and self-guided vehicles that includes two stages of hypothesis generation and verification. In the first stage, potential vehicles are hypothesized and in the second stage, all hypothesis are verified. The focus of this work is on the second stage. We extract Pyramid Histograms of Oriented Gradients (PHOG features from a traffic image as candidates of feature vectors to detect vehicles. Principle Component Analysis (PCA and Linear Discriminant Analysis (LDA are applied to these PHOG feature vectors as dimension reduction and feature selection tools parallelly. After feature fusion, we use Genetic Algorithm (GA and cosine similarity-based K Nearest Neighbor (KNN classification to improve the performance and generalization of the features. Our tests show good classification accuracy of more than 97% correct classification on realistic on-road vehicle images.

  15. Aerodynamics of wind turbines

    DEFF Research Database (Denmark)

    Hansen, Martin Otto Laver

    Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its third edition, it has been substantially updated with respect to structural dynamics and control. The new control chapter now includes details on how to design...... Turbines (VAWT). Topics covered include increasing mass flow through the turbine, performance at low and high wind speeds, assessment of the extreme conditions under which the turbine will perform and the theory for calculating the lifetime of the turbine. The classical Blade Element Momentum method...... is also covered, as are eigenmodes and the dynamic behaviour of a turbine. The book describes the effects of the dynamics and how this can be modelled in an aeroelastic code, which is widely used in the design and verification of modern wind turbines. Furthermore, it examines how to calculate...

  16. Wind Turbines Wake Aerodynamics

    DEFF Research Database (Denmark)

    Vermeer, L.; Sørensen, Jens Nørkær; Crespo, A.

    2003-01-01

    The aerodynamics of horizontal axis wind turbine wakes is studied. The contents is directed towards the physics of power extraction by wind turbines and reviews both the near and the far wake region. For the near wake, the survey is restricted to uniform, steady and parallel flow conditions......, thereby excluding wind shear, wind speed and rotor setting changes and yawed conditions. The emphasis is put on measurements in controlled conditions.For the far wake, the survey focusses on both single turbines and wind farm effects, and the experimental and numerical work are reviewed; the main interest...... is to study how the far wake decays downstream, in order to estimate the effect produced in downstream turbines.The article is further restricted to horizontal axis wind turbines and excludes all other types of turbines....

  17. Cable Aerodynamic Control

    DEFF Research Database (Denmark)

    Kleissl, Kenneth

    This dissertation investigates the possibility of preventing wind-induced cable vibrations on cable-stayed bridges using passive aerodynamic means in the form of cable surface modifications. Especially the phenomenon of rainwind induced vibrations, which is known as the most common type...... of these vibrations and capable of inducing severe vibrations. The recent increase in the number of cable stayed bridges continuously becoming longer and lighter have resulted in a high number of observations of cable vibrations. A detailed literature review of the various types of passive means led...... with a sudden change in the lift during the flow transition, which could be the reason for a dry limited amplitude vibration observed only for cables with helical applications. Dry inclined galloping was only seen with the plain reference cable model, even though only the helically filleted cable was capable...

  18. Advanced Modelling of Helicopter Nonlinear Dynamics and Aerodynamics

    OpenAIRE

    Castillo-Rivera, Salvador

    2014-01-01

    The work presented here provides a comprehensive dynamic and aerodynamic helicopter model. The possible applications of this work are wide including, control systems applications, reference and trajectory tracking methods implementation amongst others. The model configuration corresponds to a Sikorsky helicopter; a main rotor in perpendicular combination with a tail rotor. Also, a particular model of unmanned aerial vehicle has been modelled as part of collaboration with the La Laguna Univers...

  19. Aerodynamic map for soft and hard hypersonic level flight in near space

    Institute of Scientific and Technical Information of China (English)

    Ruifeng Hu; Ziniu Wu; Zhe Wu; Xiaoxin Wang; Zhongwei Tian

    2009-01-01

    In this note, we design a velocity-altitude map for hypersonic level flight in near space of altitude 20-100 km. This map displays aerodynamic-related parameters associated with near space level flight, schematically or quantitatively. Various physical conditions for the near-space level flight are then characterized, including laminar or turbulent flow, rarefaction or continuous flow, aerodynamic heating, as well as conditions for sustaining level flight with and without orbital effect. This map allows one to identify conditions to have soft flight or hard flight, and this identification would be helpful for making correct planning on detailed studies of aerodynamics or making initial design of near space vehicles.

  20. Surface effect vehicles and surface effect: General studies. Citations from the NTIS data base

    Science.gov (United States)

    Habercom, G. E., Jr.

    1980-08-01

    The bibliography contains 180 citations in which the design of surface effect vehicles, their utilization, and their aerodynamic characteristics are investigated. Vehicles or ships in marine environments are not included.

  1. 地面装甲目标声信号的混沌特征提取%Chaotic feature extraction of acoustic signals from armored vehicles

    Institute of Scientific and Technical Information of China (English)

    方向; 丁凯; 齐世福; 张卫平; 李兴华; 谢立军

    2013-01-01

    针对地面装甲目标辐射的噪声信号的非线性特性,为使智能地雷能够有效地识别目标,利用非线性动力学理论中的混沌原理对目标声信号进行特征提取.通过野外场地实验,采集到2种装甲目标在不同运行速度下的40组样本信号,采用改进C-C法求得信号时间序列的相空间重构参数——时延和嵌入维,再利用Wolf法得到了2种目标声信号的混沌特征量——最大Lyapunov指数.结果显示:同一目标声信号的最大Lyapunov指数相近,且与运动状态相关性不大;不同目标间声信号的最大Lyapunov指数相差较大,辨识度较高.结论证明,最大Lyapunov指数可以作为地面装甲目标识别的有效特征参量.%The character of acoustic signal radiated from armored vehicles are proved to be nonlinear. To effectively identify the armored vehicles, chaos theory based on nonlinear dynamics was used for extracting the feature of acoustic signals. 40 sample signals of two kinds of armored vehicles running in different speeds were collected by outdoor experiment. The reconstruction parameters (time-delay and embedding dimension) of phase space from the time series were obtained by the improved C-C method, then the largest Lyapunov exponents for each signal were calculated with these parameters by Wolf method. The results show that the values of the largest Lyapunov exponents from the same target are so close, while varying significantly between two different targets, and that the speed of the targets has no obvious impact on the largest Lyapunov exponents. It indicates that the largest Lyapunov exponent can be the characteristic parameter in target identification of acoustic signals for smart landmines.

  2. Colorectal adenocarcinoma with mucinous component: relation of MMP-13, EGFR, and E-cadherin expressions to clinicopathological features and prognosis.

    Science.gov (United States)

    Foda, Abd Al-Rahman Mohammad; El-Hawary, Amira Kamal; Aziz, Azza Abdel

    2015-06-01

    The aim of this study was to compare colorectal adenocarcinoma with mucinous component, ordinary adenocarcinoma (OA) and mucinous adenocarcinoma (MA) regarding clinicopathological parameters, survival, EGFR, MMP-13, and E-cadherin. We studied tumor tissue specimens from 28 patients with adenocarcinoma with mucinous component, 47 with OA, and 56 with MA, who underwent radical surgery from January 2007 to January 2012 at the Gastroenterology Centre, Mansoura University, Egypt. High density manual tissue microarrays were constructed and immunohistochemistry for EGFR, MMP-13, and E-cadherin was done. Colorectal adenocarcinoma with mucinous component (AWMC) was significantly associated with more perineural invasion, lower EGFR, and MMP-13 expressions than OA, with no difference in E-cadherin expression. Conversely, only microscopic abscess formation was significantly more with colorectal AWMC than MC with no difference in EGFR, MMP-13 and E-cadherin expression between both groups. Colorectal AWMC showed a better survival than MA with no difference with OA. In a univariate analysis, EGFR, MMP-13, and E-cadherin expressions did not show a significant impact on disease-free or overall survival in patients with colorectal AWMC. Colorectal AWMC remains a vague entity that resembles OA in some clinicopathological and molecular respects as well as MA. PMID:25907382

  3. Aerodynamics of Unsteady Sailing Kinetics

    Science.gov (United States)

    Keil, Colin; Schutt, Riley; Borshoff, Jennifer; Alley, Philip; de Zegher, Maximilien; Williamson, Chk

    2015-11-01

    In small sailboats, the bodyweight of the sailor is proportionately large enough to induce significant unsteady motion of the boat and sail. Sailors use a variety of kinetic techniques to create sail dynamics which can provide an increment in thrust, thereby increasing the boatspeed. In this study, we experimentally investigate the unsteady aerodynamics associated with two techniques, ``upwind leech flicking'' and ``downwind S-turns''. We explore the dynamics of an Olympic class Laser sailboat equipped with a GPS, IMU, wind sensor, and camera array, sailed expertly by a member of the US Olympic team. The velocity heading of a sailing boat is oriented at an apparent wind angle to the flow. In contrast to classic flapping propulsion, the heaving of the sail section is not perpendicular to the sail's motion through the air. This leads to heave with components parallel and perpendicular to the incident flow. The characteristic motion is recreated in a towing tank where the vortex structures generated by a representative 2-D sail section are observed using Particle Image Velocimetry and the measurement of thrust and lift forces. Amongst other results, we show that the increase in driving force, generated due to heave, is larger for greater apparent wind angles.

  4. Rotating Rig Development for Droplet Deformation/Breakup and Impact Induced by Aerodynamic Surfaces

    Science.gov (United States)

    Feo, A.; Vargas, M.; Sor, A.

    2012-01-01

    This work presents the development of a Rotating Rig Facility by the Instituto Nacional de Tecnica Aeroespacial (INTA) in cooperation with the NASA Glenn Research Center. The facility is located at the INTA installations near Madrid, Spain. It has been designed to study the deformation, breakup and impact of large droplets induced by aerodynamic bodies. The importance of these physical phenomena is related to the effects of Supercooled Large Droplets in icing clouds on the impinging efficiency of the droplets on the body, that may change should these phenomena not be taken into account. The important variables and the similarity parameters that enter in this problem are presented. The facility's components are described and some possible set-ups are explained. Application examples from past experiments are presented in order to indicate the capabilities of the new facility.

  5. 体育舞蹈肢体语言的特征分析%Features of Body Language of Sports Dance

    Institute of Scientific and Technical Information of China (English)

    汪军; 张鲁芳

    2012-01-01

    体育舞蹈肢体语言的结构由动作、舞步、步型、组合与套路组成;从时间特征分析,体育舞蹈在时间形式中呈现的"形"是真实可见的;从空间特征分析,体育舞蹈肢体语言可分为广义性空间和狭义性空间;体育舞蹈肢体语言意象性特征是由人的肢体动作所决定的。%With the research methods of literature study and comparative analysis,the paper analyses the body language of the sports dance and pointsout that the body language of sports dance is made up of movements,dance steps,stances,combinations and set patterns.The paper analyses the time features and proposes that the time form of the sports dance is tangible.The paper also points out that the body language of the sports dance can be categorized into general space and specific space.The imagery features of body language of sports dance are decided by body movements.The paper is to provide references for the basic theory researches and teaching practice of sports dance.

  6. Vehicle Real-time Location Based on Visual Perception Model

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Vehicle recognition system (VRS) plays a very important role in the field of intelligent transportation systems.A novel and intuitive method is proposed for vehicle location.The method we provide for vehicle location is based on human visual perception model technique. The perception color space HSI in this algorithm is adopted.Three color components of a color image and more potential edge patterns are integrated for solving the feature extraction problem.A fast and automatic threshold technique based on human visual perception model is also developed.The vertical edge projection and horizontal edge projection are adopted for locating left-right boundary of vehicle and top-bottom boundary of vehicle, respectively. Very promising experimental results are obtained using real-time vehicle image sequences, which have confirmed that this proposed location vehicle method is efficient and reliable, and its calculation speed meets the needs of the VRS.

  7. A NEW GENERAL 3DOF QUASI-STEADY AERODYNAMIC INSTABILITY MODEL

    DEFF Research Database (Denmark)

    Gjelstrup, Henrik; Larsen, Allan; Georgakis, Christos;

    2008-01-01

    but can generally be applied for aerodynamic instability prediction for prismatic bluff bodies. The 3DOF, which make up the movement of the model, are the displacements in the XY-plane and the rotation around the bluff body’s rotational axis. The proposed model incorporates inertia coupling between......This paper proposes a three degrees of freedom (3DOF) quasi-steady aerodynamic model and instability criterion for a bluff body which is uniform along the length axis. The model and criterion has been developed in the frame of investigating aerodynamic instability of cables due to ice accretions...... the three degrees of freedom and is capable of estimating the onset of aerodynamic instability for changes in drag, lift and moment, which is a function of wind angle of attack in relation to the x-axis of the bluff body, Reynolds number and wind angle in relation to the length axis of the bluff body...

  8. Measuring Shear Stress with a Microfluidic Sensor to improve Aerodynamic Efficiency Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Skin friction drag is directly proportional to the local shear stress of a surface and can be the largest factor in an aerodynamic body's total parasitic drag. The...

  9. GMX_CMP: usSEABED component and features data for the entire U.S. Gulf of Mexico and Caribbean (Puerto Rico and U.S. Virgin Islands)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This component data layer (_CMP.txt) file gives information about selected components (minerals, rock type, microfossils, benthic biota) and seafloor features...

  10. Analyze of aerodynamic forces acting on the Siemens Desiro railcar

    Directory of Open Access Journals (Sweden)

    Sorin ARSENE

    2016-06-01

    Full Text Available This paper aims to examine the influence of aerodynamic forces acting on the Siemens Desiro railcar, and the percentage of these forces in the total values of resistance to motion. In this regard the numerical simulation of the airflow is used as a method of analysis. We started from the 3D geometric model at a scale of 1:1 of the vehicle bodywork constructive form. The air flow simulation is performed taking into account the speed limits of the vehicle namely 0 km/ h and 140 km/ h, interval in which eight point values are chosen.

  11. Aeroassist flight experiment aerodynamics and aerothermodynamics

    Science.gov (United States)

    Brewer, Edwin B.

    1989-01-01

    The problem is to determine the transitional flow aerodynamics and aerothermodynamics, including the base flow characteristics, of the Aeroassist Flight Experiment (AFE). The justification for the computational fluid dynamic (CFD) Application stems from MSFC's system integration responsibility for the AFE. To insure that the AFE objectives are met, MSFC must understand the limitations and uncertainties of the design data. Perhaps the only method capable of handling the complex physics of the rarefied high energy AFE trajectory is Bird's Direct Simulation Monte Carlo (DSMC) technique. The 3-D code used in this analysis is applicable only to the AFE geometry. It uses the Variable Hard Sphere (VHS) collision model and five specie chemistry model available from Langley Research Center. The code is benchmarked against the AFE flight data and used as an Aeroassisted Space Transfer Vehicle (ASTV) design tool. The code is being used to understand the AFE flow field and verify or modify existing design data. Continued application to lower altitudes is testing the capability of the Numerical Aerodynamic Simulation Facility (NASF) to handle 3-D DSMC and its practicality as an ASTV/AFE design tool.

  12. Study on Forward Vehicle Detection and Distance Measurement Based on Shadow Features%基于阴影特征的前向车辆检测和测距方法研究

    Institute of Scientific and Technical Information of China (English)

    魏凯; 盛建平; 熊凯

    2013-01-01

    车辆检测汽车安全的重要课题之一.提出了一种基于阴影特征的车辆检测和测距方法:首先分析车辆底部阴影的特征,通过基于路面灰度信息的阈值分割方法分离阴影区域,然后检测阴影下边界并构建车辆的感兴趣区域,并利用归一化转动惯量特征实现车辆验证,最后根据摄像机成像模型和几何透视变换原理建立了车距测量模型,测得与前向车辆之间的距离.实验结果表明,该方法可在不同交通环境下对前向车辆实现一定的范围内的有效检测和准确测距.%Vehicles detection is one of the important subjects in auto safety. A method to detect vehicles and measure distance with the vehicle ahead based on shadows is presented. Shadow features of a vehicle at the bottom are firstly analyzed and separated using a threshold segmentation method based on the pavement gray information. The lower boder of the shadow is then detected and vehicle region of interesting is built. NMI feature is also used to validate this algorithm. Lastly, the model is built and the distance with vehicle ahead is obtained using camera projection model and geometric perspective transformation principle. Experiments are performed and the results shows that the method can detect the forward vehicle effectively and obtain the distance accurately with the vehicle ahead in different kinds of traffic situations.

  13. Principal Components of Superhigh-Dimensional Statistical Features and Support Vector Machine for Improving Identification Accuracies of Different Gear Crack Levels under Different Working Conditions

    Directory of Open Access Journals (Sweden)

    Dong Wang

    2015-01-01

    Full Text Available Gears are widely used in gearbox to transmit power from one shaft to another. Gear crack is one of the most frequent gear fault modes found in industry. Identification of different gear crack levels is beneficial in preventing any unexpected machine breakdown and reducing economic loss because gear crack leads to gear tooth breakage. In this paper, an intelligent fault diagnosis method for identification of different gear crack levels under different working conditions is proposed. First, superhigh-dimensional statistical features are extracted from continuous wavelet transform at different scales. The number of the statistical features extracted by using the proposed method is 920 so that the extracted statistical features are superhigh dimensional. To reduce the dimensionality of the extracted statistical features and generate new significant low-dimensional statistical features, a simple and effective method called principal component analysis is used. To further improve identification accuracies of different gear crack levels under different working conditions, support vector machine is employed. Three experiments are investigated to show the superiority of the proposed method. Comparisons with other existing gear crack level identification methods are conducted. The results show that the proposed method has the highest identification accuracies among all existing methods.

  14. Landing Gear Aerodynamic Noise Prediction Using Building-Cube Method

    Directory of Open Access Journals (Sweden)

    Daisuke Sasaki

    2012-01-01

    Full Text Available Landing gear noise prediction method is developed using Building-Cube Method (BCM. The BCM is a multiblock-structured Cartesian mesh flow solver, which aims to enable practical large-scale computation. The computational domain is composed of assemblage of various sizes of building blocks where small blocks are used to capture flow features in detail. Because of Cartesian-based mesh, easy and fast mesh generation for complicated geometries is achieved. The airframe noise is predicted through the coupling of incompressible Navier-Stokes flow solver and the aeroacoustic analogy-based Curle’s equation. In this paper, Curle’s equation in noncompact form is introduced to predict the acoustic sound from an object in flow. This approach is applied to JAXA Landing gear Evaluation Geometry model to investigate the influence of the detail components to flows and aerodynamic noises. The position of torque link and the wheel cap geometry are changed to discuss the influence. The present method showed good agreement with the preceding experimental result and proved that difference of the complicated components to far field noise was estimated. The result also shows that the torque link position highly affects the flow acceleration at the axle region between two wheels, which causes the change in SPL at observation point.

  15. Effects of pH on protein components of extracted oil bodies from diverse plant seeds and endogenous protease-induced oleosin hydrolysis.

    Science.gov (United States)

    Zhao, Luping; Chen, Yeming; Chen, Yajing; Kong, Xiangzhen; Hua, Yufei

    2016-06-01

    Plant seeds are used to extract oil bodies for diverse applications, but oil bodies extracted at different pH values exhibit different properties. Jicama, sunflower, peanut, castor bean, rapeseed, and sesame were selected to examine the effects of pH (6.5-11.0) on the protein components of oil bodies and the oleosin hydrolysis in pH 6.5-extracted oil bodies. In addition to oleosins, many extrinsic proteins (globulins, 2S albumin, and enzymes) were present in pH 6.5-extracted oil bodies. Globulins were mostly removed at pH 8.0, whereas 2S albumins were removed at pH 11.0. At pH 11.0, highly purified oil bodies were obtained from jicama, sunflower, peanut, and sesame, whereas lipase remained in the castor bean oil bodies and many enzymes in the rapeseed oil bodies. Endogenous protease-induced hydrolysis of oleosins occurred in all selected plant seeds. Oleosins with larger sizes were hydrolysed more quickly than oleosins with smaller sizes in each plant seed.

  16. Effects of pH on protein components of extracted oil bodies from diverse plant seeds and endogenous protease-induced oleosin hydrolysis.

    Science.gov (United States)

    Zhao, Luping; Chen, Yeming; Chen, Yajing; Kong, Xiangzhen; Hua, Yufei

    2016-06-01

    Plant seeds are used to extract oil bodies for diverse applications, but oil bodies extracted at different pH values exhibit different properties. Jicama, sunflower, peanut, castor bean, rapeseed, and sesame were selected to examine the effects of pH (6.5-11.0) on the protein components of oil bodies and the oleosin hydrolysis in pH 6.5-extracted oil bodies. In addition to oleosins, many extrinsic proteins (globulins, 2S albumin, and enzymes) were present in pH 6.5-extracted oil bodies. Globulins were mostly removed at pH 8.0, whereas 2S albumins were removed at pH 11.0. At pH 11.0, highly purified oil bodies were obtained from jicama, sunflower, peanut, and sesame, whereas lipase remained in the castor bean oil bodies and many enzymes in the rapeseed oil bodies. Endogenous protease-induced hydrolysis of oleosins occurred in all selected plant seeds. Oleosins with larger sizes were hydrolysed more quickly than oleosins with smaller sizes in each plant seed. PMID:26830569

  17. Naval Aerodynamics Test Facility (NATF)

    Data.gov (United States)

    Federal Laboratory Consortium — The NATF specializes in Aerodynamics testing of scaled and fullsized Naval models, research into flow physics found on US Navy planes and ships, aerosol testing and...

  18. The aerodynamics of wind turbines

    DEFF Research Database (Denmark)

    Sørensen, Jens Nørkær; Mikkelsen, Robert Flemming; Troldborg, Niels;

    2013-01-01

    In the paper we present state-of-the-art of research in wind turbine aerodynamics. We start be giving a brief historical review and a survey over aerodynamic research in wind energy. Next, we focus on some recent research results obtained by our wind energy group at Department of Mechanical Engin...... Engineering at DTU. In particular, we show some new results on the classical problem of the ideal rotor and present a series of new results from an on-going research project dealing with the modelling and simulation of turbulent flow structures in the wake behind wind turbines.......In the paper we present state-of-the-art of research in wind turbine aerodynamics. We start be giving a brief historical review and a survey over aerodynamic research in wind energy. Next, we focus on some recent research results obtained by our wind energy group at Department of Mechanical...

  19. Turbine Aerodynamics Design Tool Development

    Science.gov (United States)

    Huber, Frank W.; Turner, James E. (Technical Monitor)

    2001-01-01

    This paper presents the Marshal Space Flight Center Fluids Workshop on Turbine Aerodynamic design tool development. The topics include: (1) Meanline Design/Off-design Analysis; and (2) Airfoil Contour Generation and Analysis. This paper is in viewgraph form.

  20. Computational aerodynamics and artificial intelligence

    Science.gov (United States)

    Mehta, U. B.; Kutler, P.

    1984-01-01

    The general principles of artificial intelligence are reviewed and speculations are made concerning how knowledge based systems can accelerate the process of acquiring new knowledge in aerodynamics, how computational fluid dynamics may use expert systems, and how expert systems may speed the design and development process. In addition, the anatomy of an idealized expert system called AERODYNAMICIST is discussed. Resource requirements for using artificial intelligence in computational fluid dynamics and aerodynamics are examined. Three main conclusions are presented. First, there are two related aspects of computational aerodynamics: reasoning and calculating. Second, a substantial portion of reasoning can be achieved with artificial intelligence. It offers the opportunity of using computers as reasoning machines to set the stage for efficient calculating. Third, expert systems are likely to be new assets of institutions involved in aeronautics for various tasks of computational aerodynamics.