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. Aerodynamic analysis of an isolated vehicle wheel

    International Nuclear Information System (INIS)

    Increasing fuel prices force the manufacturers to look into all aspects of car aerodynamics including wheels, tyres and rims in order to minimize their drag. By diminishing the aerodynamic drag of vehicle the fuel consumption will decrease, while driving safety and comfort will improve. In order to properly illustrate the impact of a rotating wheel aerodynamics on the car body, precise analysis of an isolated wheel should be performed beforehand. In order to represent wheel rotation in contact with the ground, presented CFD simulations included Moving Wall boundary as well as Multiple Reference Frame should be performed. Sliding mesh approach is favoured but too costly at the moment. Global and local flow quantities obtained during simulations were compared to an experiment in order to assess the validity of the numerical model. Results of investigation illustrates dependency between type of simulation and coefficients (drag and lift). MRF approach proved to be a better solution giving result closer to experiment. Investigation of the model with contact area between the wheel and the ground helps to illustrate the impact of rotating wheel aerodynamics on the car body.

  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. 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...

  9. 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...

  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. Concepts are presented for morphing aircraft, to enable the aircraft to...

  11. 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.

  12. Wheel arch aerodynamics of a modern road vehicle

    International Nuclear Information System (INIS)

    A geometrically faithful model of the Aston Martin V12 Vanquish was formed in 3D CAD and used to perform an extensive CFD study into the airflow in and around the wheel arch of the vehicle. Parameters such as spin ratio, ground clearance, vertical and horizontal insertion into the wheel arch and the yaw angles experienced during cornering, were all under investigation. The additional aim of the research was to validate or refute the use of CFD as a tool in this complex area of fluid flow. This research serves to highlight a number of problems and potential solutions in the use of CFD. Meshing problems can be eliminated with increased computational power and suggestions have been made to improve the modeling of rotating boundaries that include radial features such as wheel spokes. Much of the CFD data ties well with previously conducted experimental work, if not numerically then in trend. Without additional physical validation however, it is difficult to ascertain the overall accuracy and usefulness of the remaining results, which have not yet been conducted in physical reality. Despite its limitations, the use of CFD permitted an extensive analysis in a comparatively short length of time and served to highlight potential areas for increased scrutiny. As an example, results from the final yaw angle case drew attention to a potential concern for aerodynamic destabilisation of the vehicle during cornering, generating lift on the front arch of the car that is already lifted due to cornering forces and body roll. (author)

  13. 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...

  14. 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

  15. 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.

  16. Particle Methods in Bluff Body Aerodynamics

    DEFF Research Database (Denmark)

    Rasmussen, Johannes Tophøj

    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...... important. This dissertation focuses on the use of vortex particle methods and computational efficiency. The work is divided into three parts. A novel method for the simulation of the aerodynamic admittance in bluff body aerodynamics is presented. The method involves a model for describing oncoming...... turbulence in two-dimensional discrete vortex method simulations by seeding the upstream flow with vortex particles. The turbulence is generated prior to the simulations and is based on analytic spectral densities of the atmospheric turbulence and a coherence function defining the spatial correlation of the...

  17. 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...

  18. 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.

  19. 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.

  20. 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.

  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. 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.

  3. Optimization of physical training of students of high school with regard to quantitative features muscular components of their bodies

    Directory of Open Access Journals (Sweden)

    Kolokoltsev M.M.

    2015-02-01

    Full Text Available Purpose : to provide a quantitative description of the muscle component of students’ body with regard to their motor characteristics to improve training in the discipline "Physical Education". Material : a study of muscular component of the body in 1937 students aged 17-20 years old of age living in the Baikal region. Motor quality students were evaluated by tests. Problem analysis was conducted based on the data of Polish authors. Results : the dependence of the amount of content in muscle mass in the body of the frequency of physical training in high school. Also found significantly higher levels of performance in motor tests in the group of students with a high level of expression of muscle mass. Conclusions : the studies have shown a direct relationship content of lean body mass of locomotor activity. Set better indicator values in tests of physical fitness with a high content of muscle tissue. Lack of exercise training on older years is recommended to compensate for self-manage motor activities.

  4. 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.

  5. 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 ...

  6. 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.

  7. 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.

  8. Transonic Blunt Body Aerodynamic Coefficients Computation

    Science.gov (United States)

    Sancho, Jorge; Vargas, M.; Gonzalez, Ezequiel; Rodriguez, Manuel

    2011-05-01

    In the framework of EXPERT (European Experimental Re-entry Test-bed) accurate transonic aerodynamic coefficients are of paramount importance for the correct trajectory assessment and parachute deployment. A combined CFD (Computational Fluid Dynamics) modelling and experimental campaign strategy was selected to obtain accurate coefficients. A preliminary set of coefficients were obtained by CFD Euler inviscid computation. Then experimental campaign was performed at DNW facilities at NLR. A profound review of the CFD modelling was done lighten up by WTT results, aimed to obtain reliable values of the coefficients in the future (specially the pitching moment). Study includes different turbulence modelling and mesh sensitivity analysis. Comparison with the WTT results is explored, and lessons learnt are collected.

  9. A Multi-Year Program Plan for the Aerodynamic Design of Heavy Vehicles; ANNUAL

    International Nuclear Information System (INIS)

    The project tasks and deliverables are as follows: Computations and Experiments-(1) Simulation and analysis of a range of generic shapes, simplified to more complex, representative of tractor and integrated tractor-trailer flow characteristics using computational tools, (2) The establishment of an experimental data base for tractor-trailer models for code/computational method development and validation. The first shapes to be considered will be directed towards the investigation of tractor-trailer gaps and mismatch of tractor-trailer heights. (3) The evaluation and documentation of effective computational approaches for application to heavy vehicle aerodynamics based on the benchmark results with existing and advanced computational tools compared to experimental data, and (4) Computational tools and experimental methods for use by industry, National Laboratories, and universities for the aerodynamic modeling of heavy truck vehicles. Evaluation of current and new technologies-(1) The evaluation and documentation of current and new technologies for drag reduction based on published literature and continued communication with the heavy vehicle industry (e.g., identification and prioritization of tractor-trailer drag-sources, blowing and/or suction devices, body shaping, new experimental methods or facilities), and the identification and analysis of tractor and integrated tractor-trailer aerodynamic problem areas and possible solution strategies. (2) Continued industrial site visits. It should be noted that ''CFD tools'' are not only the actual computer codes, but descriptions of appropriate numerical solution methods. Part of the project effort will be to determine the restrictions or avenues for technology transfer

  10. 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.

  11. 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.

  12. 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

  13. 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

  14. Hyper-X Research Vehicle (HXRV) Experimental Aerodynamics Test Program Overview

    Science.gov (United States)

    Holland, Scott D.; Woods, William C.; Engelund, Walter C.

    2000-01-01

    This paper provides an overview of the experimental aerodynamics test program to ensure mission success for the autonomous flight of the Hyper-X Research Vehicle (HXRV). The HXRV is a 12-ft long, 2700 lb lifting body technology demonstrator designed to flight demonstrate for the first time a fully airframe integrated scramjet propulsion system. Three flights are currently planned, two at Mach 7 and one at Mach 10, beginning in the fall of 2000. The research vehicles will be boosted to the prescribed scramjet engine test point where they will separate from the booster, stabilize. and initiate engine test. Following 5+ seconds of powered flight and 15 seconds of cowl-open tares, the cowl will close and the vehicle will fly a controlled deceleration trajectory which includes numerous control doublets for in-flight aerodynamic parameter identification. This paper reviews the preflight testing activities, wind tunnel models, test rationale. risk reduction activities, and sample results from wind tunnel tests supporting the flight trajectory of the HXRV from hypersonic engine test point through subsonic flight termination.

  15. Micro air vehicle-motivated computational biomechanics in bio-flights: aerodynamics, flight dynamics and maneuvering stability

    Science.gov (United States)

    Liu, Hao; Nakata, Toshiyuki; Gao, Na; Maeda, Masateru; Aono, Hikaru; Shyy, Wei

    2010-12-01

    Aiming at developing an effective tool to unveil key mechanisms in bio-flight as well as to provide guidelines for bio-inspired micro air vehicles (MAVs) design, we propose a comprehensive computational framework, which integrates aerodynamics, flight dynamics, vehicle stability and maneuverability. This framework consists of (1) a Navier-Stokes unsteady aerodynamic model; (2) a linear finite element model for structural dynamics; (3) a fluid-structure interaction (FSI) model for coupled flexible wing aerodynamics aeroelasticity; (4) a free-flying rigid body dynamic (RBD) model utilizing the Newtonian-Euler equations of 6DoF motion; and (5) flight simulator accounting for realistic wing-body morphology, flapping-wing and body kinematics, and a coupling model accounting for the nonlinear 6DoF flight dynamics and stability of insect flapping flight. Results are presented based on hovering aerodynamics with rigid and flexible wings of hawkmoth and fruitfly. The present approach can support systematic analyses of bio- and bio-inspired flight.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. Lateral dynamic features of a railway vehicle

    DEFF Research Database (Denmark)

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

    2016-01-01

    The lateral dynamic features of a railway vehicle are investigated using two similar wheel/rail contact models: the Vermeulen-Johnson and the Shen-Hedrick-Elkins models. The symmetric/asymmetric bifurcation behaviour and chaotic motions of the railway vehicle are investigated in great detail 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...

  4. 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}.

  5. Wind Tunnel Testing on Crosswind Aerodynamic Forces Acting on Railway Vehicles

    Science.gov (United States)

    Kwon, Hyeok-Bin; Nam, Seong-Won; You, Won-Hee

    This study is devoted to measure the aerodynamic forces acting on two railway trains, one of which is a high-speed train at 300km/h maximum operation speed, and the other is a conventional train at the operating speed 100km/h. The three-dimensional train shapes have been modeled as detailed as possible including the inter-car, the upper cavity for pantograph, and the bogie systems. The aerodynamic forces on each vehicle of the trains have been measured in the subsonic wind tunnel with 4m×3m test section of Korea Aerospace Research Institute at Daejeon, Korea. The aerodynamic forces and moments of the train models have been plotted for various yaw angles and the characteristics of the aerodynamic coefficients has been discussed relating to the experimental conditions.

  6. 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.

  7. 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.

  8. 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...

  9. 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.

  10. Aerodynamic study of a blended wing body, comparison with a conventional transport airplane.

    OpenAIRE

    Ayuso Moreno, Luis Manuel; Sant Palma, Rodolfo; Plagaro Pascual, Luis

    2006-01-01

    Blended-wing-body (BWB) aircraft are being studied with interest and effort to improve economic efficiency and to overcome operational and infrastructure related problems associated to the increasing size of conventional transport airplanes. The objective of the research reported here is to assess the aerodynamic feasibility and operational efficiency of a great size, blended wing body layout, a configuration which has many advantages. To this end, the conceptual aerodynamic design process of...

  11. 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

  12. 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.

  13. Studies on aerodynamic interferences between the components of transport airplane using unstructured Navier-Stokes simulations

    International Nuclear Information System (INIS)

    It is well known that the aerodynamic interference flows widely exist between the components of conventional transport airplane, for example, the wing-fuselage juncture flow, wing-pylon-nacelle flow and tail-fuselage juncture flow. The main characteristic of these aerodynamic interferences is flow separation, which will increase the drag, reduce the lift and cause adverse influence on the stability and controllability of the airplane. Therefore, the modern civil transport designers should do their best to eliminate negative effects of aerodynamic interferences, which demands that the aerodynamic interferences between the aircraft components should be predicted and analyzed accurately. Today's CFD techniques provide us powerful and efficient analysis tools to achieve this objective. In this paper, computational investigations of the interferences between transport aircraft components have been carried out by using a viscous flow solver based on mixed element type unstructured meshes. (author)

  14. 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...

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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%..

  2. 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.

  3. Aerodynamic characteristics of bodies with rectangular cross section

    Science.gov (United States)

    Knoche, H. G.; Schamel, W.; Esch, H.; Schneider, W.

    Systematic wind tunnel tests for a series of missile bodies were conducted by varying cross section shape and body length in the subsonic Mach number range and up to high angles of attack. Tests with a body-wing and a body-tail configuration were performed in order to investigate the body-wing and body-tail interference for bodies of revolution and bodies with rectangular cross section. At a constant angle of attack, the boxlike body supplies far more normal force than the body of revolution with the same cross section area. The boxlike body shows strong coupling effects between the pitch, yaw and roll. The interference effect of the wing and body can be described well, in the case of boxlike bodies with wings in high or low wing positions, by the known slender body interference factors, assuming the width of the box to be the diameter of an equivalent, axially symetrical body.

  4. 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

  5. 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.

  6. 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.

  7. 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

  8. Investigation of Tractor Base Bleeding for Heavy Vehicle Aerodynamic Drag Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, J; Salari, K; Storms, B

    2007-10-25

    One of the main contributors to the aerodynamic drag of a heavy vehicle is tractor-trailer gap drag, which arises when the vehicle operates within a crosswind. Under this operating condition, freestream flow is entrained into the tractor-trailer gap, imparting a momentum exchange to the vehicle and subsequently increasing the aerodynamic drag. While a number of add-on devices, including side extenders, splitter plates, vortex stabilizers, and gap sealers, have been previously tested to alleviate this source of drag, side extenders remain the primary add-on device of choice for reducing tractor-trailer gap drag. However, side extenders are not without maintenance and operational issues. When a heavy vehicle pivots sharply with respect to the trailer, as can occur during loading or unloading operations, the side extenders can become crushed against the trailer. Consequently, fleet operators are forced to incur additional costs to cover the repair or replacement of the damaged side extenders. This issue can be overcome by either shortening the side extenders or by devising an alternative drag reduction concept that can perform just as effectively as side extenders. To explore such a concept, we investigate tractor base bleeding as a means of reducing gap drag. Wind tunnel measurements are made on a 1:20 scale heavy vehicle model at a vehicle width-based Reynolds number of 420,000. The tractor bleeding flow, which is delivered through a porous material embedded within the tractor base, is introduced into the tractor-trailer gap at bleeding coefficients ranging from 0.0-0.018. To determine the performance of tractor base bleeding under more realistic operating conditions, computational fluid dynamics simulations are performed on a full-scale heavy vehicle within a crosswind for bleeding coefficients ranging from 0.0-0.13.

  9. 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...

  10. Aerodynamics of a bio-inspired flexible flapping-wing micro air vehicle

    International Nuclear Information System (INIS)

    MAVs (micro air vehicles) with a maximal dimension of 15 cm and nominal flight speeds of around 10 m s−1, operate in a Reynolds number regime of 105 or lower, in which most natural flyers including insects, bats and birds fly. Furthermore, due to their light weight and low flight speed, the MAVs' flight characteristics are substantially affected by environmental factors such as wind gust. Like natural flyers, the wing structures of MAVs are often flexible and tend to deform during flight. Consequently, the aero/fluid and structural dynamics of these flyers are closely linked to each other, making the entire flight vehicle difficult to analyze. We have recently developed a hummingbird-inspired, flapping flexible wing MAV with a weight of 2.4–3.0 g and a wingspan of 10–12 cm. In this study, we carry out an integrated study of the flexible wing aerodynamics of this flapping MAV by combining an in-house computational fluid dynamic (CFD) method and wind tunnel experiments. A CFD model that has a realistic wing planform and can mimic realistic flexible wing kinematics is established, which provides a quantitative prediction of unsteady aerodynamics of the four-winged MAV in terms of vortex and wake structures and their relationship with aerodynamic force generation. Wind tunnel experiments further confirm the effectiveness of the clap and fling mechanism employed in this bio-inspired MAV as well as the importance of the wing flexibility in designing small flapping-wing MAVs.

  11. 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.

  12. 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.

  13. Aerodynamic Characteristics of a Revised Target Drone Vehicle at Mach Numbers from 1.60 to 2.86

    Science.gov (United States)

    Blair, A. B., Jr.; Babb, C. Donald

    1968-01-01

    An investigation has been conducted in the Langley Unitary Plan wind tunnel to determine the aerodynamic characteristics of a revised target drone vehicle through a Mach number range from 1.60 to 2.86. The vehicle had canard surfaces and a swept clipped-delta wing with twin tip-mounted vertical tails.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. The aerodynamic underbody panel of the new Audi A4

    Energy Technology Data Exchange (ETDEWEB)

    Steuer, U.; Seifert, H.; Neuberger, J. [Audi AG, Ingolstadt (Germany)

    2001-07-01

    Modern vehicle designs today more than ever before demand careful functional coordination and adjustment of all components to each other. At the same time a thrifty and efficient use of all resources must be ensured. A strongly design-oriented make of automobile, as is the case with Audi, needs freedom in the design of the outer vehicle body. Before the aerodynamic requirements in the product brief can be met in the light of these background constraints, a optimum result for the vehicle as a whole will not be possible unless the underbody area is also included in any examination of airflow properties. (orig.)

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Flying snakes: Aerodynamics of body cross-sectional shape

    OpenAIRE

    Holden, Daniel Patrick

    2011-01-01

    Chrysopelea paradisi, also known as the flying snake, possesses one of the most unique forms of aerial locomotion found in nature, using its entire body as a dynamic lifting surface without the use of wings or membranes. Unlike other airborne creatures, this species lacks appendages to aid in controlling its flight trajectory and producing lift. The snake exhibits exception gliding and maneuvering capabilities compared with other species of gliders despite this lack of appendages. While gl...

  5. 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.

  6. Investigation on thermal performance of high temperature multilayer insulations for hypersonic vehicles under aerodynamic heating condition

    International Nuclear Information System (INIS)

    Hypersonic vehicles have to withstand extremely high aerodynamic heating and pressure loads during the ascent and reentry stages. Multilayer thermal insulations have been widely designed in thermal protection systems to keep the temperature of underlying structure within an acceptable limit. In this study, a theoretical model is built combining radiation and conduction heat transfer in high temperature multilayer insulations under aerodynamic heating conditions. After a reliable validation with previous references, the effects of the layout, the number and the location of the foils, the density of insulation materials and the emissivity of the surface of foils on the insulation performance of multilayer thermal insulations are investigated, respectively. It is found that there exists an optimal number of insulation layers for best thermal performance and the layout of radiation foils has no evident effect. In addition, the insulation performance is much better when the foils are near the cold boundary, and when the density of insulation material and the emissivity of the surface of foils are higher, the temperature of bottom surface is lower. - Highlights: • High temperature multilayer thermal insulation structures are concerned. • Effects of layer number and foils layout/location are observed. • Effects of insulation materials density and foils emissivity are studied. • There exists an optimal number of insulation layers. • It is suggested to locate the foils near the cold internal surface

  7. Wing and body motion and aerodynamic and leg forces during take-off in droneflies.

    Science.gov (United States)

    Chen, Mao Wei; Zhang, Yan Lai; Sun, Mao

    2013-12-01

    Here, we present a detailed analysis of the take-off mechanics in droneflies performing voluntary take-offs. Wing and body kinematics of the insects during take-off were measured using high-speed video techniques. Based on the measured data, the inertia force acting on the insect was computed and the aerodynamic force of the wings was calculated by the method of computational fluid dynamics. Subtracting the aerodynamic force and the weight from the inertia force gave the leg force. In take-off, a dronefly increases its stroke amplitude gradually in the first 10-14 wingbeats and becomes airborne at about the 12th wingbeat. The aerodynamic force increases monotonously from zero to a value a little larger than its weight, and the leg force decreases monotonously from a value equal to its weight to zero, showing that the droneflies do not jump and only use aerodynamic force of flapping wings to lift themselves into the air. Compared with take-offs in insects in previous studies, in which a very large force (5-10 times of the weight) generated either by jumping legs (locusts, milkweed bugs and fruit flies) or by the 'fling' mechanism of the wing pair (butterflies) is used in a short time, the take-off in the droneflies is relatively slow but smoother. PMID:24132205

  8. Aerodynamic heating and surface temperatures on vehicles for computer-aided design studies

    Science.gov (United States)

    Dejarnette, F. R.; Kania, L. A.; Chitty, A.

    1983-01-01

    A computer subprogram has been developed to calculate aerodynamic and radiative heating rates and to determine surface temperatures by integrating the heating rates along the trajectory of a vehicle. Convective heating rates are calculated by applying the axisymmetric analogue to inviscid surface streamlines and using relatively simple techniques to calculate laminar, transitional, or turbulent heating rates. Options are provided for the selection of gas model, transition criterion, turbulent heating method, Reynolds Analogy factor, and entropy-layer swallowing effects. Heating rates are compared to experimental data, and the time history of surface temperatures are given for a high-speed trajectory. The computer subprogram is developed for preliminary design and mission analysis where parametric studies are needed at all speeds.

  9. 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.

  10. 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.

  11. 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.

  12. How are bodies special? Effects of body features on spatial reasoning.

    Science.gov (United States)

    Yu, Alfred B; Zacks, Jeffrey M

    2016-06-01

    Embodied views of cognition argue that cognitive processes are influenced by bodily experience. This implies that when people make spatial judgments about human bodies, they bring to bear embodied knowledge that affects spatial reasoning performance. Here, we examined the specific contribution to spatial reasoning of visual features associated with the human body. We used two different tasks to elicit distinct visuospatial transformations: object-based transformations, as elicited in typical mental rotation tasks, and perspective transformations, used in tasks in which people deliberately adopt the egocentric perspective of another person. Body features facilitated performance in both tasks. This result suggests that observers are particularly sensitive to the presence of a human head and body, and that these features allow observers to quickly recognize and encode the spatial configuration of a figure. Contrary to prior reports, this facilitation was not related to the transformation component of task performance. These results suggest that body features facilitate task components other than spatial transformation, including the encoding of stimulus orientation. PMID:26252072

  13. 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.

  14. 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.

  15. 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.

  16. System Component Modelling of Electric Vehicles and Charging Infrastructure

    OpenAIRE

    Tsakmakis, Emanuel

    2012-01-01

    The objective of this research is to develop a model for the electrical components that are involved in charging and discharging of an electric vehicle (EV). This will enable testing differ-ent energy management strategies that improve energy efficiency, battery lifetime, and ener-gy availability. Furthermore, the model will enable the investigation of vehicle to grid (V2G), thermal preconditioning of vehicles, and an economic analysis and optimization. In order to achieve the above goals,...

  17. 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.

  18. Hypersonic aerodynamic characteristics of a family of power-law, wing body configurations

    Science.gov (United States)

    Townsend, J. C.

    1973-01-01

    The configurations analyzed are half-axisymmetric, power-law bodies surmounted by thin, flat wings. The wing planform matches the body shock-wave shape. Analytic solutions of the hypersonic small disturbance equations form a basis for calculating the longitudinal aerodynamic characteristics. Boundary-layer displacement effects on the body and the wing upper surface are approximated. Skin friction is estimated by using compressible, laminar boundary-layer solutions. Good agreement was obtained with available experimental data for which the basic theoretical assumptions were satisfied. The method is used to estimate the effects of power-law, fineness ratio, and Mach number variations at full-scale conditions. The computer program is included.

  19. 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

  20. The computation of steady 3-D separated flows over aerodynamic bodies at incidence and yaw

    Science.gov (United States)

    Pulliam, T. H.; Pan, D.

    1986-01-01

    This paper describes the implementation of a general purpose 3-D NS code and its application to simulated 3-D separated vortical flows over aerodynamic bodies. The thin-layer Reynolds-averaged NS equations are solved by an implicit approximate factorization scheme. The pencil data structure enables the code to run on very fine grids using only limited incore memories. Solutions of a low subsonic flow over an inclined ellipsoid are compared with experimental data to validate the code. Transonic flows over a yawed elliptical wing at incidence are computed and separations occurred at different yaw angles are discussed.

  1. 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...

  2. Assessment Of The Aerodynamic And Aerothermodynamic Performance Of The USV-3 High-Lift Re-Entry Vehicle

    Science.gov (United States)

    Pezzella, Giuseppe; Richiello, Camillo; Russo, Gennaro

    2011-05-01

    This paper deals with the aerodynamic and aerothermodynamic trade-off analysis carried out with the aim to design a hypersonic flying test bed (FTB), namely USV3. Such vehicle will have to be launched with a small expendable launcher and shall re-enter the Earth atmosphere allowing to perform several experiments on critical re-entry phenomena. The demonstrator under study is a re-entry space glider characterized by a relatively simple vehicle architecture able to validate hypersonic aerothermodynamic design database and passenger experiments, including thermal shield and hot structures. Then, a summary review of the aerodynamic characteristics of two FTB concepts, compliant with a phase-A design level, has been provided hereinafter. Indeed, several design results, based both on engineering approach and computational fluid dynamics, are reported and discussed in the paper.

  3. Hybrid Wing Body Planform Design with Vehicle Sketch Pad

    Science.gov (United States)

    Wells, Douglas P.; Olson, Erik D.

    2011-01-01

    The objective of this paper was to provide an update on NASA s current tools for design and analysis of hybrid wing body (HWB) aircraft with an emphasis on Vehicle Sketch Pad (VSP). NASA started HWB analysis using the Flight Optimization System (FLOPS). That capability is enhanced using Phoenix Integration's ModelCenter(Registered TradeMark). Model Center enables multifidelity analysis tools to be linked as an integrated structure. Two major components are linked to FLOPS as an example; a planform discretization tool and VSP. The planform discretization tool ensures the planform is smooth and continuous. VSP is used to display the output geometry. This example shows that a smooth & continuous HWB planform can be displayed as a three-dimensional model and rapidly sized and analyzed.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. On aerodynamic modelling of an insect-like flapping wing in hover for micro air vehicles.

    Science.gov (United States)

    Zbikowski, Rafał

    2002-02-15

    This theoretical paper discusses recent advances in the fluid dynamics of insect and micro air vehicle (MAV) flight and considers theoretical analyses necessary for their future development. The main purpose is to propose a new conceptual framework and, within this framework, two analytic approaches to aerodynamic modelling of an insect-like flapping wing in hover in the context of MAVs. The motion involved is periodic and is composed of two half-cycles (downstroke and upstroke) which, in hover, are mirror images of each other. The downstroke begins with the wing in the uppermost and rearmost position and then sweeps forward while pitching up and plunging down. At the end of the half-cycle, the wing flips, so that the leading edge points backwards and the wing's lower surface becomes its upper side. The upstroke then follows by mirroring the downstroke kinematics and executing them in the opposite direction. Phenomenologically, the interpretation of the flow dynamics involved, and adopted here, is based on recent experimental evidence obtained by biologists from insect flight and related mechanical models. It is assumed that the flow is incompressible, has low Reynolds number and is laminar, and that two factors dominate: (i) forces generated by the bound leading-edge vortex, which models flow separation; and (ii) forces due to the attached part of the flow generated by the periodic pitching, plunging and sweeping. The first of these resembles the analogous phenomenon observed on sharp-edged delta wings and is treated as such. The second contribution is similar to the unsteady aerodynamics of attached flow on helicopter rotor blades and is interpreted accordingly. Theoretically, the fluid dynamic description is based on: (i) the superposition of the unsteady contributions of wing pitching, plunging and sweeping; and (ii) adding corrections due to the bound leading-edge vortex and wake distortion. Viscosity is accounted for indirectly by imposing the Kutta condition

  9. Advanced components for electric and hybrid electric vehicles. Workshop proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Stricklett, K.L.; Cookson, A.H.; Bartholomew, R.W.; Leedy, T. [National inst. of Standards and Technology, Gaithersburg, MD (United States). Electricity Div.

    1994-12-31

    This is a key period in the development of electric and hybrid electric vehicles. The landmark 1990 legislation in California requires that 2 percent of new automobiles be zero emission vehicles in 1998, rising to 10 percent in the year 2005. This can only be met by electric vehicles. The purpose of the workshop was to concentrate on the technologies to improve the design, performance, manufacturability, and economics of the critical components for the next generation of electric and hybrid electric vehicles for the year 2000 and beyond. The workshop began with invited speakers to cover the general topics of impact of the California legislation, Federal agency programs, development of standards, infrastructure needs, advanced battery development, and the imperatives for commercial success of electric and hybrid electric vehicles. Working sessions were five parallel meetings on Energy Conversion Systems, Energy Storage Systems, Electric Propulsion Systems, Controls and Instrumentation, and Ancillary Systems.

  10. 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.

  11. 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...

  12. 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...

  13. Procedures for finding optimal layouts of vehicle components with respect to durability

    Energy Technology Data Exchange (ETDEWEB)

    Eschenauer, H.A.; Idelberger, H. [Univ. of Siegen (Germany); Bieker, G.; Rottler, A. [Bombardier, Siegen-Netphen (Germany); Weinert, M. [Ford Motor Comp., Cologne (Germany)

    2007-07-01

    When designing complete systems or system components, it is of vital importance for the manufacturers to optimally fulfill the continuously increasing demands pertaining to safety, durability, reduction of energy consumption, noise reduction, improvement of comfort, accuracy, etc. This applies to all types of traffic and transportation systems like rail vehicles, automobiles, airplanes and ships. By combining structural analysis and simulation methods with optimization algorithms, required specifications can be met faster and more reliably, and hence the production development cycles can be substantially reduced. This paper shall give an overview on results of a method with the features of a damage approximation as precisely as possible on the one hand and, on the other hand, a load-time history with few different load cycles so that a nonlinear calculation can be performed in the shortest possible time. Simulations with rigidly and elastically modeled components like bogie frames or carbodies show that depending on the type of modeling substantial differences may occur with respect to dynamic behavior and the interaction quantity between the bodies. This aspect has to be taken into consideration for quantitatively sufficient fatigue strength and durability calculation. Mathematical optimization procedures are in general an efficient tool to guarantee the optimal fulfillment of all required design objectives and constraints in all stages of the design process. Some of the procedures are illustrated at two examples (bogie frame, carbody). (orig.)

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. Characteristic imaging features of body packers: a pictorial essay.

    Science.gov (United States)

    Ab Hamid, Suzana; Abd Rashid, Saiful Nizam; Mohd Saini, Suraini

    2012-06-01

    The drug-trafficking business has risen tremendously because of the current increased demand for illegal narcotics. The smugglers conceal the drugs in their bodies (body packers) in order to bypass the tight security at international borders. A suspected body packer will normally be sent to the hospital for imaging investigations to confirm the presence of drugs in the body. Radiologists, therefore, need to be familiar with and able to identify drug packets within the human body because they shoulder the legal responsibilities. This pictorial essay describes the characteristic imaging features of drug packets within the gastrointestinal tract. PMID:22415809

  2. 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.

  3. 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.

  4. 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...

  5. 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...

  6. Numerical simulation of the transient aerodynamic phenomena induced by passing manoeuvres

    CERN Document Server

    Uystepruyst, David

    2015-01-01

    Several three-dimensional Unsteady Reynolds-Averaged Navier-Stokes (URANS) simulations of the passing generic vehicles (Ahmed bodies) are presented. The relative motion of vehicles was obtained using a combination of deforming and sliding computational grids. The vehicle studied is an Ahmed body with an angle of the rear end slanted surface of $30^{\\circ}$. Several different relative velocities and transversal distances between vehicles were studied. The aerodynamic influence of the passage on the overtaken vehicle was studied. The results of the simulations were found to agree well with the existing experimental data. Numerical results were used to explain effects of the overtaking manoeuvre on the main aerodynamic coefficients.

  7. 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...

  8. 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.

  9. 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

  10. 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.

  11. Development of the PRSEUS Multi-Bay Pressure Box for a Hybrid Wing Body Vehicle

    Science.gov (United States)

    Jegley, Dawn C.; Velicki, Alexander

    2015-01-01

    NASA has created the Environmentally Responsible Aviation Project to explore and document the feasibility, benefits, and technical risk of advanced vehicle configurations and enabling technologies that will reduce the impact of aviation on the environment. A critical aspect of this pursuit is the development of a lighter, more robust airframe that will enable the introduction of unconventional aircraft configurations that have higher lift-to-drag ratios, reduced drag, and lower community noise. Although such novel configurations like the Hybrid Wing Body (HWB) offer better aerodynamic performance as compared to traditional tube-and-wing aircraft, their blended wing shapes also pose significant new design challenges. Developing an improved structural concept that is capable of meeting the structural weight fraction allocated for these non-circular pressurized cabins is the primary obstacle in implementing large lifting-body designs. To address this challenge, researchers at NASA and The Boeing Company are working together to advance new structural concepts like the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS), which is an integrally stiffened panel design that is stitched together and designed to maintain residual load-carrying capabilities under a variety of damage scenarios. The large-scale multi-bay fuselage test article described in this paper is the final specimen in a building-block test program that was conceived to demonstrate the feasibility of meeting the structural weight goals established for the HWB pressure cabin.

  12. Moving Vehicle Recognition and Feature Extraction From Tunnel Monitoring Videos

    OpenAIRE

    Aiyan Lu; Luo Zhong; Lin Li; Qingbo Wang

    2013-01-01

    In recent decades, many government agencies and famous universities are researching the intelligent traffic video monitoring system. According to the tunnel monitoring video, this paper uses the combination of background subtraction method and three frame differencing method for moving vehicle detection , and designs the geometric parameters and combined parameters for vehicle classification, finally makes up a vehicle classifier, based on these characteristics parameters.  

  13. March 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; McCallen, R; Ross, J; Salari, K

    1999-03-01

    A Working Group Meeting on Heavy Vehicle Aerodynamic Drag was held at Lawrence Livermore National Laboratory, Livermore, California on March 11, 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 the experimental results for the integrated tractor-trailer benchmark geometry called the Sandia Model in the NASA Ames 7 ft x 10 ft wind tunnel. 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), Lawrence Livermore National Laboratory (LLNL), Sandia National Laboratories (SNL), University of Southern California (USC), California Institute of Technology (Caltech), and NASA Ames Research Center.This report contains the technical presentations (viewgraphs) delivered at the Meeting, briefly summarizes the comments and conclusions, and outlines the future action items.

  14. Computer assisted vehicle service featuring signature analysis and artificial intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Boscove, J.A.; Kurtz, H.L.; Prince, J.E.; Wiegand, W.P.

    1989-01-03

    This patent describes a diagnostic method for use in diagnosing a vehicle utilizing a diagnostic system, the vehicle having an on-board computer control system for monitoring and controlling vehicle functions and the diagnostic system including a technician terminal having a diagnostic controller for processing diagnostic signals representative of vehicle conditions the controller having data entry means, data output means and storage means for storing vehicle parameters and diagnostic routines and the technician terminal having a display means for providing instructions for fault repair sequences.

  15. Aerodynamic characteristics of the ventilated design for flapping wing micro air vehicle.

    Science.gov (United States)

    Zhang, G Q; Yu, S C M

    2014-01-01

    Inspired by superior flight performance of natural flight masters like birds and insects and based on the ventilating flaps that can be opened and closed by the changing air pressure around the wing, a new flapping wing type has been proposed. It is known that the net lift force generated by a solid wing in a flapping cycle is nearly zero. However, for the case of the ventilated wing, results for the net lift force are positive which is due to the effect created by the "ventilation" in reducing negative lift force during the upstroke. The presence of moving flaps can serve as the variable in which, through careful control of the areas, a correlation with the decrease in negative lift can be generated. The corresponding aerodynamic characteristics have been investigated numerically by using different flapping frequencies and forward flight speeds. PMID:24683339

  16. 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.

  17. 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

  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. 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.

  1. Exploring point-cloud features from partial body views for gender classification

    Science.gov (United States)

    Fouts, Aaron; McCoppin, Ryan; Rizki, Mateen; Tamburino, Louis; Mendoza-Schrock, Olga

    2012-06-01

    In this paper we extend a previous exploration of histogram features extracted from 3D point cloud images of human subjects for gender discrimination. Feature extraction used a collection of concentric cylinders to define volumes for counting 3D points. The histogram features are characterized by a rotational axis and a selected set of volumes derived from the concentric cylinders. The point cloud images are drawn from the CAESAR anthropometric database provided by the Air Force Research Laboratory (AFRL) Human Effectiveness Directorate and SAE International. This database contains approximately 4400 high resolution LIDAR whole body scans of carefully posed human subjects. Success from our previous investigation was based on extracting features from full body coverage which required integration of multiple camera images. With the full body coverage, the central vertical body axis and orientation are readily obtainable; however, this is not the case with a one camera view providing less than one half body coverage. Assuming that the subjects are upright, we need to determine or estimate the position of the vertical axis and the orientation of the body about this axis relative to the camera. In past experiments the vertical axis was located through the center of mass of torso points projected on the ground plane and the body orientation derived using principle component analysis. In a natural extension of our previous work to partial body views, the absence of rotational invariance about the cylindrical axis greatly increases the difficulty for gender classification. Even the problem of estimating the axis is no longer simple. We describe some simple feasibility experiments that use partial image histograms. Here, the cylindrical axis is assumed to be known. We also discuss experiments with full body images that explore the sensitivity of classification accuracy relative to displacements of the cylindrical axis. Our initial results provide the basis for further

  2. Commercial vehicles. Fundamentals, systems, components. 3. rev. and enl. ed.; Nutzfahrzeugtechnik. Grundlagen, Systeme, Komponenten

    Energy Technology Data Exchange (ETDEWEB)

    Hoepke, E. (ed.); Appel, W.; Braehler, H.; Dahlhaus, U.; Esch, T.; Graefenstein, J.

    2004-09-15

    This book presents all components and types of commercial vehicles, i.e. classic design theory, vehicle mechanics and theromodynamics, as well as the latest developments in engine and vehicle engineering up to electronic vehicle management. This is the third edition; it contains some new chapters on four-wheel drive design, commercial vehicle engineering, test cycles up to EURO 5, particulate filters and four-wheel drives for light commercial vehicles. Subjects: Fundamentals; Undercarriage; Design of commercial vehicles; Supporting structures and top structures; Propulsion systems; Speed converters; Electrical and electronic systems; Seals; Outlook. (orig.)

  3. Identification method of satellite local components based on combined feature metrics

    Science.gov (United States)

    Zhi, Xi-yang; Hou, Qing-yu; Zhang, Wei; Sun, Xuan

    2014-11-01

    In order to meet the requirements of identification of satellite local targets, a new method based on combined feature metrics is proposed. Firstly, the geometric features of satellite local targets including body, solar panel and antenna are analyzed respectively, and then the cluster of each component are constructed based on the combined feature metrics of mathematical morphology. Then the corresponding fractal clustering criterions are given. A cluster model is established, which determines the component classification according to weighted combination of the fractal geometric features. On this basis, the identified targets in the satellite image can be recognized by computing the matching probabilities between the identified targets and the clustered ones, which are weighted combinations of the component fractal feature metrics defined in the model. Moreover, the weights are iteratively selected through particle swarm optimization to promote recognition accuracy. Finally, the performance of the identification algorithm is analyzed and verified. Experimental results indicate that the algorithm is able to identify the satellite body, solar panel and antenna accurately with identification probability up to 95%, and has high computing efficiency. The proposed method can be applied to identify on-orbit satellite local targets and possesses potential application prospects on spatial target detection and identification.

  4. 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.

  5. Co-Optimization of Blunt Body Shapes for Moving Vehicles

    Science.gov (United States)

    Brown, James L. (Inventor); Garcia, Joseph A (Inventor); Kinney, David J. (Inventor); Bowles, Jeffrey V (Inventor); Mansour, Nagi N (Inventor)

    2014-01-01

    A method and associated system for multi-disciplinary optimization of various parameters associated with a space vehicle that experiences aerocapture and atmospheric entry in a specified atmosphere. In one embodiment, simultaneous maximization of a ratio of landed payload to vehicle atmospheric entry mass, maximization of fluid flow distance before flow separation from vehicle, and minimization of heat transfer to the vehicle are performed with respect to vehicle surface geometric parameters, and aerostructure and aerothermal vehicle response for the vehicle moving along a specified trajectory. A Pareto Optimal set of superior performance parameters is identified.

  6. 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...

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

    Institute of Scientific and Technical Information of China (English)

    刘毅; 靳宏斌

    2014-01-01

    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 .%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。

  8. Asynchronous vehicle pose correction using visual detection of ground features

    Science.gov (United States)

    Harnarinesingh, Randy E. S.; Syan, Chanan S.

    2014-07-01

    The inherent noise associated with odometry manifests itself as errors in localization for autonomous vehicles. Visual odometry has been previously used in order to supplement classical vehicle odometry. However, visual odometry is limited in its ability to reduce errors in localization for large travel distances that entail the cumulative summing of individual frame-to-frame image errors. In this paper, a novel machine vision approach for tiled surfaces is proposed to address this problem. Tile edges in a laboratory environment are used to define a travel trajectory for the Quansar Qbot (autonomous vehicle) built on the iRobot iRoomba platform with a forward facing camera. Tile intersections are used to enable asynchronous error recovery for vehicle position and orientation. The proposed approach employs real-time image classification and is feasible for error mitigation for large travel distances. The average position error for an 8m travel distance using classical odometry was measured to be 0.28m. However, implementation of the proposed approach resulted in an error of 0.028m. The proposed approach therefore significantly reduces pose estimation error and could be used to supplement existing modalities such as GPS and Laser-based range sensors.

  9. 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

  10. 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...

  11. 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.

  12. 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

  13. 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)

  14. 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

  15. 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.

  16. 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...

  17. 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 ...

  18. 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

  19. 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.

  20. 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...

  1. Probe Vehicle Track-Matching Algorithm Based on Spatial Semantic Features

    Science.gov (United States)

    Luo, Y.; Song, X.; Zheng, L.; Yang, C.; Yu, M.; Sun, M.

    2015-07-01

    The matching of GPS received locations to roads is challenging. Traditional matching method is based on the position of the GPS receiver, the vehicle position and vehicle behavior near the receiving time. However, for probe vehicle trajectories, the sampling interval is too sparse and there is a poor correlation between adjacent sampling points, so it cannot partition the GPS noise through the historical positions. For the data mining of probe vehicle tracks based on spatial semantics, the matching is learned from the traditional electronic navigation map matching, and it is proposed that the probe vehicle track matching algorithm is based on spatial semantic features. Experimental results show that the proposed global-path matching method gets a good matching results, and restores the true path through the probe vehicle track.

  2. Object recognition by component features: are there age differences.

    Science.gov (United States)

    Frazier, L; Hoyer, W J

    1992-01-01

    This study extended aspects of Biederman's (1987) recognition-by-components (RBC) theory to the analysis of age differences in the recognition of incomplete visually-presented objects. RBC theory predicts that objects are recognizable or recoverable under conditions of fragmentation if a sufficient amount of essential structural information remains available. Objects are rendered nonrecoverable by the omission or obstruction of essential structural features at vertices and areas of concavity. Fifteen young adults and 15 older adults participated in a study of the effects of amount (25%, 45%, 65%) and type of fragmentation (recoverable, nonrecoverable) on object naming. Age-related declines in recognizing incomplete objects were associated with the amount of fragmentation, but type of fragmentation did not affect the performance of older adults. For the young adults, accuracy of performance was affected by both amount and type of fragmentation, consistent with Biederman's RBC theory. These results were interpreted as suggesting that age-related declines in perceptual closure performance have to do with non-structural factors such as the ability to inferentially augment degraded or missing visual information. PMID:1446700

  3. 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

  4. 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.

  5. 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.

  6. Aerodynamic shape optimization of wing and wing-body configurations using control theory

    Science.gov (United States)

    Reuther, James; Jameson, Antony

    1995-01-01

    This paper describes the implementation of optimization techniques based on control theory for wing and wing-body design. In previous studies it was shown that control theory could be used to devise an effective optimization procedure for airfoils and wings in which the shape and the surrounding body-fitted mesh are both generated analytically, and the control is the mapping function. Recently, the method has been implemented for both potential flows and flows governed by the Euler equations using an alternative formulation which employs numerically generated grids, so that it can more easily be extended to treat general configurations. Here results are presented both for the optimization of a swept wing using an analytic mapping, and for the optimization of wing and wing-body configurations using a general mesh.

  7. 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...

  8. Effects of reaction control system jet flow field interactions on the aerodynamic characteristics of a 0.010-scale space shuttle orbiter model in the Langley Research Center 31 inch CFHT (OA85)

    Science.gov (United States)

    Daileda, J. J.; Marroquin, J.

    1974-01-01

    An experimental investigation was conducted to obtain detailed effects on supersonic vehicle hypersonic aerodynamic and stability and control characteristics of reaction control system jet flow field interactions with the local vehicle flow field. A 0.010-scale model was used. Six-component force data and wing, elevon, and body flap surface pressure data were obtained through an angle-of-attack range of -10 to +35 degrees with 0 deg angle of sideslip. The test was conducted with yaw, pitch and roll jet simulation at a free-stream Mach number of 10.3 and reaction control system plume simulation of flight dynamic pressures of 5, 10 and 20 PSF.

  9. 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...

  10. 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.

  11. Aerodynamic damping in oscillatory pitching motion of canard-body combinations in unsteady supersonic regime

    International Nuclear Information System (INIS)

    A method of solution is developed in the present paper for studying the unsteady supersonic flow past a cruciform canard - conical body system, represented in the figure, which executes an oscillatory pitching motion of rotation. The generality of the analysis permits particular solutions such as the case of symmetrical cruciform canards (for l1=l2=l) used mainly in missile applications, and tail-body configurations (for l2=0 pr l2→∞ used in aeronautical applications, as well as more general solutions. Attached supersonic flow past the system, associated with small amplitude oscillations of reasonably low frequency with respect to a mean equilibrium position are assumed in this paper. As a result, the steady flow past the canard-body system at an attitude defined by the mean equilibrium position can be separated from the actual flow; general methods of solution for this steady flow have been established. The aim of the present analysis is to develop a method of solution for the unsteady motion resulting from the actual flow after the above separation, which incorporates the effects of the system oscillations. (author)

  12. Shape Design of Lifting body Based on Genetic Algorithm

    OpenAIRE

    Yongyuan Li; Yi Jiang; Chunping Huang

    2010-01-01

    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-objecti...

  13. Program LRCDM2: Improved aerodynamic prediction program for supersonic canard-tail missiles with axisymmetric bodies

    Science.gov (United States)

    Dillenius, Marnix F. E.

    1985-01-01

    Program LRCDM2 was developed for supersonic missiles with axisymmetric bodies and up to two finned sections. Predicted are pressure distributions and loads acting on a complete configuration including effects of body separated flow vorticity and fin-edge vortices. The computer program is based on supersonic panelling and line singularity methods coupled with vortex tracking theory. Effects of afterbody shed vorticity on the afterbody and tail-fin pressure distributions can be optionally treated by companion program BDYSHD. Preliminary versions of combined shock expansion/linear theory and Newtonian/linear theory have been implemented as optional pressure calculation methods to extend the Mach number and angle-of-attack ranges of applicability into the nonlinear supersonic flow regime. Comparisons between program results and experimental data are given for a triform tail-finned configuration and for a canard controlled configuration with a long afterbody for Mach numbers up to 2.5. Initial tests of the nonlinear/linear theory approaches show good agreement for pressures acting on a rectangular wing and a delta wing with attached shocks for Mach numbers up to 4.6 and angles of attack up to 20 degrees.

  14. Vibration Suppression of a Helicopter Fuselage by Pendulum Absorbers : Rigid-Body Blades with Aerodynamic Excitation Force

    Science.gov (United States)

    Nagasaka, Imao; Ishida, Yukio; Koyama, Takayuki; Fujimatsu, Naoki

    Currently, some kinds of helicopters use pendulum absorbers in order to reduce vibrations. Present pendulum absorbers are designed based on the antiresonance concept used in the linear theory. However, since the vibration amplitudes of the pendulum are not small, it is considered that the nonlinearity has influence on the vibration characteristics. Therefore, the best suppression cannot be attained by using the linear theory. In a helicopter, periodic forces act on the blades due to the influences of the air thrust. These periodic forces act on the blades with the frequency which is the integer multiple of the rotational speed of the rotor. Our previous study proposed a 2-degree-of-freedom (2DOF) model composed of a rotor blade and a pendulum absorber. The blade was considered as a rigid body and it was excited by giving a sinusoidal deflection at its end. The present paper proposes a 3DOF model that is more similar to the real helicopter, since the freedom of the fuselage is added and the periodic forces are applied to the blade by aerodynamic force. The vibration is analyzed considering the nonlinear characteristics. The resonance curves of rotor blades with pendulum absorbers are obtained analytically and experimentally. It is clarified that the most efficient condition is obtained when the natural frequency of the pendulum is a little bit different from the frequency of the external force. Various unique nonlinear characteristics, such as bifurcations, are also shown.

  15. PREFACE: Aerodynamic sound Aerodynamic sound

    Science.gov (United States)

    Akishita, Sadao

    2010-02-01

    The modern theory of aerodynamic sound originates from Lighthill's two papers in 1952 and 1954, as is well known. I have heard that Lighthill was motivated in writing the papers by the jet-noise emitted by the newly commercialized jet-engined airplanes at that time. The technology of aerodynamic sound is destined for environmental problems. Therefore the theory should always be applied to newly emerged public nuisances. This issue of Fluid Dynamics Research (FDR) reflects problems of environmental sound in present Japanese technology. The Japanese community studying aerodynamic sound has held an annual symposium since 29 years ago when the late Professor S Kotake and Professor S Kaji of Teikyo University organized the symposium. Most of the Japanese authors in this issue are members of the annual symposium. I should note the contribution of the two professors cited above in establishing the Japanese community of aerodynamic sound research. It is my pleasure to present the publication in this issue of ten papers discussed at the annual symposium. I would like to express many thanks to the Editorial Board of FDR for giving us the chance to contribute these papers. We have a review paper by T Suzuki on the study of jet noise, which continues to be important nowadays, and is expected to reform the theoretical model of generating mechanisms. Professor M S Howe and R S McGowan contribute an analytical paper, a valuable study in today's fluid dynamics research. They apply hydrodynamics to solve the compressible flow generated in the vocal cords of the human body. Experimental study continues to be the main methodology in aerodynamic sound, and it is expected to explore new horizons. H Fujita's study on the Aeolian tone provides a new viewpoint on major, longstanding sound problems. The paper by M Nishimura and T Goto on textile fabrics describes new technology for the effective reduction of bluff-body noise. The paper by T Sueki et al also reports new technology for the

  16. 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.

  17. 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.

  18. A Profit-Maximizing Method for the Partitioning of Embedded Software Features in Motor Vehicles

    OpenAIRE

    Baecker, Oliver; Weppner, Harald; Strube, Jochen

    2009-01-01

    As the system design of in-car embedded systems becomes more and more modular and motor vehicles get increasingly connected to enterprise systems based on Car-2-X technology, the integration of additional embedded software features becomes technically feasible throughout the product lifecycle. For car manufacturers, this opens up the opportunity to sell additional embedded software features to their customers at a later time, thus generating subsequent revenue in addition to the initial sale....

  19. Introducing New AdaBoost Features for Real-Time Vehicle Detection

    CERN Document Server

    Stanciulescu, Bogdan; Moutarde, Fabien

    2009-01-01

    This paper shows how to improve the real-time object detection in complex robotics applications, by exploring new visual features as AdaBoost weak classifiers. These new features are symmetric Haar filters (enforcing global horizontal and vertical symmetry) and N-connexity control points. Experimental evaluation on a car database show that the latter appear to provide the best results for the vehicle-detection problem.

  20. 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.

  1. 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.

  2. Body Focused Repetitive Behaviors (BFRBs) and Personality Features

    DEFF Research Database (Denmark)

    Chamberlain, Samuel; Odlaug, Brian Lawrence

    2014-01-01

    Body focused repetitive behaviors (BFRBs) represent a collection of motoric acts that can become ingrained, habitual, and functionally impairing. They often relate to excessive grooming of the body or skin. Although these pathological habits have been described since ancient times, only recently...

  3. 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

  4. 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.

  5. 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...

  6. 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

  7. 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

  8. Advanced components for electric and hybrid electric vehicles: Proceedings of a workshop

    Energy Technology Data Exchange (ETDEWEB)

    Stricklett, K.L. [ed.; Cookson, A.H.; Bartholomew, R.W.; Leedy, T. [National Inst. of Standards and Tech., Gaithersburg, MD (United States)

    1994-03-01

    This is a key period in the development of electric and hybrid electric vehicles. The landmark 1990 legislation in California requires that two percent of new automobiles be zero emission vehicles in 1998, rising to 10 percent in the year 2005. This can only be met by electric vehicles. The purpose of the workshop was to concentrate on the technologies to improve the design, performance, manufacturability, and economics of the critical components for the next generation of electric and hybrid electric vehicles for the year 2000 and beyond. The workshop began with invited speakers to cover the general topics of impact of the California legislation, federal agency programs, development of standards, infrastructure needs, advanced battery development, and the imperatives for commercial success of electric and hybrid electric vehicles. Working sessions were five parallel meetings on energy conversion systems, energy storage systems, electric propulsion systems, controls and instrumentation, and ancillary systems.

  9. 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.)

  10. Cortical Lewy body dementia: clinical features and classification.

    OpenAIRE

    Gibb, W R; Luthert, P. J.; Janota, I; Lantos, P. L.

    1989-01-01

    Seven patients, aged 65-72 years, are described with dementia and cortical Lewy bodies. In one patient a Parkinsonian syndrome was followed by dementia and motor neuron disease. In the remaining six patients dementia was accompanied by dysphasia, dyspraxia and agnosia. One developed a Parkinsonian syndrome before the dementia, in three cases a Parkinsonian syndrome occurred later, and in two cases not at all. All patients showed Lewy bodies and cell loss in the substantia nigra, locus coerule...

  11. [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

  12. 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

  13. 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...

  14. 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) ...

  15. 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,...

  16. 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

  17. 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

  18. Using Pressure- and Temperature-Sensitive Paint for Global Surface Pressure and Temperature Measurements on the Aft-Body of a Capsule Reentry Vehicle

    Science.gov (United States)

    Watkins, A. Neal; Buck, Gregory M.; Leighty, Bradley D.; Lipford, William E.; Oglesby, Donald M.

    2008-01-01

    Pressure Sensitive Paint (PSP) and Temperature Sensitive Paint (TSP) were used to visualize and quantify the surface interactions of reaction control system (RCS) jets on the aft body of capsule reentry vehicle shapes. The first model tested was an Apollo-like configuration and was used to focus primarily on the effects of the forward facing roll and yaw jets. The second model tested was an early Orion Crew Module configuration blowing only out of its forward-most yaw jet, which was expected to have the most intense aerodynamic heating augmentation on the model surface. This paper will present the results from the experiments, which show that with proper system design, both PSP and TSP are effective tools for studying these types of interaction in hypersonic testing environments.

  19. 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.

  20. 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...

  1. 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.

  2. 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.

  3. 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)

  4. 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.

  5. Feature selection for neural network based defect classification of ceramic components using high frequency ultrasound.

    Science.gov (United States)

    Kesharaju, Manasa; Nagarajah, Romesh

    2015-09-01

    The motivation for this research stems from a need for providing a non-destructive testing method capable of detecting and locating any defects and microstructural variations within armour ceramic components before issuing them to the soldiers who rely on them for their survival. The development of an automated ultrasonic inspection based classification system would make possible the checking of each ceramic component and immediately alert the operator about the presence of defects. Generally, in many classification problems a choice of features or dimensionality reduction is significant and simultaneously very difficult, as a substantial computational effort is required to evaluate possible feature subsets. In this research, a combination of artificial neural networks and genetic algorithms are used to optimize the feature subset used in classification of various defects in reaction-sintered silicon carbide ceramic components. Initially wavelet based feature extraction is implemented from the region of interest. An Artificial Neural Network classifier is employed to evaluate the performance of these features. Genetic Algorithm based feature selection is performed. Principal Component Analysis is a popular technique used for feature selection and is compared with the genetic algorithm based technique in terms of classification accuracy and selection of optimal number of features. The experimental results confirm that features identified by Principal Component Analysis lead to improved performance in terms of classification percentage with 96% than Genetic algorithm with 94%. PMID:26081920

  6. Multi-Body Unsteady Aerodynamics in 2D Applied to aVertical-Axis Wind Turbine Using a Vortex Method

    OpenAIRE

    Österberg, David

    2010-01-01

    Vertical axis wind turbines (VAWT) have many advantages over traditional Horizontalaxis wind turbines (HAWT).One of the more severe problem of VAWTs are the complicated aerodynamicbehavior inherent in the concept. Incontrast to HAWTs the blades experience varying angle of attack during its orbitalmotion. The unsteady flowleads to unsteady loads, and hence, to increased risk for problems with fatigue.A tool for aerodynamic analysis of vertical axis wind turbines has been developed.The model, a...

  7. Error analysis of rigid body posture measurement system based on circular feature points

    Science.gov (United States)

    Huo, Ju; Cui, Jishan; Yang, Ning

    2015-02-01

    For monocular vision pose parameters determine the problem, feature-based target feature points on the plane quadrilateral, an improved two-stage iterative algorithm is proposed to improve the optimization of rigid body posture measurement calculating model. Monocular vision rigid body posture measurement system is designed; experimentally in each coordinate system determined coordinate a unified method to unify the each feature point measure coordinates; theoretical analysis sources of error from rigid body posture measurement system simulation experiments. Combined with the actual experimental analysis system under the condition of simulation error of pose accuracy of measurement, gives the comprehensive error of measurement system, for improving measurement precision of certain theoretical guiding significance.

  8. 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.

  9. Abort performance for a winged-body single-stage to orbit vehicle

    Science.gov (United States)

    Lyon, Jeffery A.

    1995-08-01

    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.

  10. 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

  11. Mechanical component design for upgrading of whole body counter ND7500

    International Nuclear Information System (INIS)

    The Whole Body Counter (WBC) ND7500 is a bed type counting system that used for measuring radionuclide in the entire human body. Malaysian Nuclear Agency has this system, which savaged from Institute of Medical Research (IMR) in 1987. This system consists of a nuclear counting system and mechanical system that totally inoperable due to its counting system failures. In April 2003, both counting system and the mechanical system were tested. The mechanical component is working properly but needs some readjustment for the bed movement while for the counting system, only detectors can work but with a poor detecting capability. During IAEA expert visits on July 2003, both detectors were verified cannot be use any longer due to poor resolution and aging factor and a single (3 x 5 x 16) inches rectangular NaI(Tl) detector was then purchased in the end of 2004 to replace (3 x 5) inches cylindrical Na(Tl) detectors. The existing shielding cannot accommodate this new (3 x 5 x 16) inches dimension and the (5 x 16) inches detecting area. Therefore, shielding modification has been done based on effective detecting area and positioning test results. A new detector's entrance and detector stage were built at the bottom shielding. A new features, which is a detectors protection also been developed for detector safety. This upgrading task successfully accomplished as from experimental the design of positioning component can make system operated easily and also can give a good results to meets user's requirements. (Author)

  12. 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, ...

  13. 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

  14. 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.

  15. 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...

  16. 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.

  17. 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...

  18. 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.

  19. A Multidisciplinary Performance Analysis of a Lifting-Body Single-Stage-to-Orbit Vehicle

    Science.gov (United States)

    Tartabini, Paul V.; Lepsch, Roger A.; Korte, J. J.; Wurster, Kathryn E.

    2000-01-01

    Lockheed Martin Skunk Works (LMSW) is currently developing a single-stage-to-orbit reusable launch vehicle called VentureStar(TM) A team at NASA Langley Research Center participated with LMSW in the screening and evaluation of a number of early VentureStar(TM) configurations. The performance analyses that supported these initial studies were conducted to assess the effect of a lifting body shape, linear aerospike engine and metallic thermal protection system (TPS) on the weight and performance of the vehicle. These performance studies were performed in a multidisciplinary fashion that indirectly linked the trajectory optimization with weight estimation and aerothermal analysis tools. This approach was necessary to develop optimized ascent and entry trajectories that met all vehicle design constraints. Significant improvements in ascent performance were achieved when the vehicle flew a lifting trajectory and varied the engine mixture ratio during flight. Also, a considerable reduction in empty weight was possible by adjusting the total oxidizer-to-fuel and liftoff thrust-to-weight ratios. However, the optimal ascent flight profile had to be altered to ensure that the vehicle could be trimmed in pitch using only the flow diverting capability of the aerospike engine. Likewise, the optimal entry trajectory had to be tailored to meet TPS heating rate and transition constraints while satisfying a crossrange requirement.

  20. 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.

  1. 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

  2. Effects of wing leading-edge radius and Reynolds number on longitudinal aerodynamic characteristics of highly swept wing-body configurations at subsonic speeds

    Science.gov (United States)

    Henderson, W. P.

    1976-01-01

    An investigation was conducted in the Langley low turbulence pressure tunnel to determine the effects of wing leading edge radius and Reynolds number on the longitudinal aerodynamic characteristics of a series of highly swept wing-body configurations. The tests were conducted at Mach numbers below 0.30, angles of attack up to 16 deg, and Reynolds numbers per meter from 6.57 million to 43.27 million. The wings under study in this investigation had leading edge sweep angles of 61.7 deg, 64.61 deg, and 67.01 deg in combination with trailing edge sweep angles of 0 deg and 40.6 deg. The leading edge radii of each wing planform could be varied from sharp to nearly round.

  3. Two independent mushroom body output circuits retrieve the six discrete components of Drosophila aversive memory.

    Science.gov (United States)

    Bouzaiane, Emna; Trannoy, Séverine; Scheunemann, Lisa; Plaçais, Pierre-Yves; Preat, Thomas

    2015-05-26

    Understanding how the various memory components are encoded and how they interact to guide behavior requires knowledge of the underlying neural circuits. Currently, aversive olfactory memory in Drosophila is behaviorally subdivided into four discrete phases. Among these, short- and long-term memories rely, respectively, on the γ and α/β Kenyon cells (KCs), two distinct subsets of the ∼2,000 neurons in the mushroom body (MB). Whereas V2 efferent neurons retrieve memory from α/β KCs, the neurons that retrieve short-term memory are unknown. We identified a specific pair of MB efferent neurons, named M6, that retrieve memory from γ KCs. Moreover, our network analysis revealed that six discrete memory phases actually exist, three of which have been conflated in the past. At each time point, two distinct memory components separately recruit either V2 or M6 output pathways. Memory retrieval thus features a dramatic convergence from KCs to MB efferent neurons. PMID:25981036

  4. Two Independent Mushroom Body Output Circuits Retrieve the Six Discrete Components of Drosophila Aversive Memory

    Directory of Open Access Journals (Sweden)

    Emna Bouzaiane

    2015-05-01

    Full Text Available Understanding how the various memory components are encoded and how they interact to guide behavior requires knowledge of the underlying neural circuits. Currently, aversive olfactory memory in Drosophila is behaviorally subdivided into four discrete phases. Among these, short- and long-term memories rely, respectively, on the γ and α/β Kenyon cells (KCs, two distinct subsets of the ∼2,000 neurons in the mushroom body (MB. Whereas V2 efferent neurons retrieve memory from α/β KCs, the neurons that retrieve short-term memory are unknown. We identified a specific pair of MB efferent neurons, named M6, that retrieve memory from γ KCs. Moreover, our network analysis revealed that six discrete memory phases actually exist, three of which have been conflated in the past. At each time point, two distinct memory components separately recruit either V2 or M6 output pathways. Memory retrieval thus features a dramatic convergence from KCs to MB efferent neurons.

  5. 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.

  6. Use of Flexible Body Coupled Loads in Assessment of Day of Launch Flight Loads

    Science.gov (United States)

    Starr, Brett R.; Yunis, Isam; Olds, Aaron D.

    2011-01-01

    A Day of Launch flight loads assessment technique that determines running loads calculated from flexible body coupled loads was developed for the Ares I-X Flight Test Vehicle. The technique was developed to quantify DOL flight loads in terms of structural load components rather than the typically used q-alpha metric to provide more insight into the DOL loads. In this technique, running loads in the primary structure are determined from the combination of quasi-static aerodynamic loads and dynamic loads. The aerodynamic loads are calculated as a function of time using trajectory parameters passed from the DOL trajectory simulation and are combined with precalculated dynamic loads using a load combination equation. The potential change in aerodynamic load due to wind variability during the countdown is included in the load combination. In the event of a load limit exceedance, the technique allows the identification of what load component is exceeded, a quantification of how much the load limit is exceeded, and where on the vehicle the exceedance occurs. This technique was used to clear the Ares I-X FTV for launch on October 28, 2009. This paper describes the use of coupled loads in the Ares I-X flight loads assessment and summarizes the Ares I-X load assessment results.

  7. Frequency Domain Fatigue Assessment of Vehicle Component under Random Load Spectrum

    International Nuclear Information System (INIS)

    This research is focused on the application of frequency domain based fatigue life predict methods on vehicle component. The basic theory of these approaches is based on the frequency-based signals, the probability density function (PDF) of signals and Miner cumulative damage criterion. A typical suspension virtual prototype model is established to derive dynamic loading arisen from random road exciting. Several kinds of fatigue life predicting approaches in frequency domain are applied and compared. The influence factors for these methods, such as PSD average methods, frequency ranges and frequency intervals are also discussed. Appropriate results can be obtained at last.

  8. 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

  9. 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.

  10. 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.

  11. 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 +/

  12. 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

  13. Three-body recombination of two-component cold atomic gases into deep dimers in an optical model

    DEFF Research Database (Denmark)

    Mikkelsen, Mathias; Jensen, A. S.; Fedorov, D. V.; Zinner, Nikolaj Thomas

    2015-01-01

    We consider three-body recombination into deep dimers in a mass-imbalanced two-component atomic gas. We use an optical model where a phenomenological imaginary potential is added to the lowest adiabatic hyper-spherical potential. The consequent imaginary part of the energy eigenvalue corresponds to...... the decay rate or recombination probability of the three-body system. The method is formulated in details and the relevant qualitative features are discussed as functions of scattering lengths and masses. We use zero-range model in analyses of recent recombination data. The dominating scattering...... length is usually related to the non-equal two-body systems. We account for temperature smearing which tends to wipe out the higher-lying Efimov peaks. The range and the strength of the imaginary potential determine positions and shapes of the Efimov peaks as well as the absolute value of the...

  14. 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

  15. Flight Dynamics of an Aeroshell Using an Attached Inflatable Aerodynamic Decelerator

    Science.gov (United States)

    Cruz, Juan R.; Schoenenberger, Mark; Axdahl, Erik; Wilhite, Alan

    2009-01-01

    An aeroelastic analysis of the behavior of an entry vehicle utilizing an attached inflatable aerodynamic decelerator during supersonic flight is presented. The analysis consists of a planar, four degree of freedom simulation. The aeroshell and the IAD are assumed to be separate, rigid bodies connected with a spring-damper at an interface point constraining the relative motion of the two bodies. Aerodynamic forces and moments are modeled using modified Newtonian aerodynamics. The analysis includes the contribution of static aerodynamic forces and moments as well as pitch damping. Two cases are considered in the analysis: constant velocity flight and planar free flight. For the constant velocity and free flight cases with neutral pitch damping, configurations with highly-stiff interfaces exhibit statically stable but dynamically unstable aeroshell angle of attack. Moderately stiff interfaces exhibit static and dynamic stability of aeroshell angle of attack due to damping induced by the pitch angle rate lag between the aeroshell and IAD. For the free-flight case, low values of both the interface stiffness and damping cause divergence of the aeroshell angle of attack due to the offset of the IAD drag force with respect to the aeroshell center of mass. The presence of dynamic aerodynamic moments was found to influence the stability characteristics of the vehicle. The effect of gravity on the aeroshell angle of attack stability characteristics was determined to be negligible for the cases investigated.

  16. 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.

  17. 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.

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

    OpenAIRE

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

    2016-01-01

    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 a...

  19. 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.

  20. Powertrain Component Inspection from Mid-Level Blends Vehicle Aging Study

    Energy Technology Data Exchange (ETDEWEB)

    Shoffner, Brent [Southwest Research Institute, San Antonio; Johnson, Ryan [Southwest Research Institute, San Antonio; Heimrich, Martin J. [Southwest Research Institute, San Antonio; Lochte, Michael [Southwest Research Institute, San Antonio

    2010-11-01

    The Energy Independence and Security Act of 2007 calls on the nation to significantly increase its use of renewable fuels to meet its transportation energy needs. The law expands the renewable fuel standard to require use of 36 billion gallons of renewable fuel by 2022. Given that ethanol is the most widely used renewable fuel in the U.S. market, ethanol will likely make up a significant portion of the 36-billion-gallon requirement. The vast majority of ethanol used in the United States is blended with gasoline to create E10-gasoline with up to 10% ethanol. The remaining ethanol is sold in the form of E85 - a gasoline blend with as much as 85% ethanol that can only be used in flexible-fuel vehicles (FFVs). Consumption of E85 is at present limited by both the size of the FFV fleet and the number of E85 fueling stations. Gasoline consumption in the United States is currently about 140 billion gallons per year; thus the maximum use of ethanol as E10 is only about 14 billion gallons. While the U.S. Department of Energy (DOE) remains committed to expanding the E85 infrastructure, that market represented less than 1% of the ethanol consumed in 2010 and will not be able to absorb projected volumes of ethanol in the near term. Because of these factors, DOE and others have been assessing the viability of using mid-level ethanol blends (E15 or E20) as a way to accommodate growing volumes of ethanol. The DOE Mid-Level Ethanol Blends Test Program has been under way since 2007, supported jointly by the Office of the Biomass Program and the Vehicle Technologies Program. One of the larger projects, the Catalyst Durability Study, or Vehicle Aging Study, will be completed early in calendar year 2011. The following report describes a subproject of the Vehicle Aging Study in which powertrain components from 18 of the vehicles were examined at Southwest Research Institute under contract to Oak Ridge National Laboratory (ORNL).

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. 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.

  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. AIAA Applied Aerodynamics Conference, 8th, Portland, OR, Aug. 20-22, 1990, Technical Papers. Parts 1 ampersand 2

    International Nuclear Information System (INIS)

    The present conference discusses topics in CFD methods and their validation, vortices and vortical flows, STOL/VSTOL aerodynamics, boundary layer transition and separation, wing airfoil aerodynamics, laminar flow, supersonic and hypersonic aerodynamics, CFD for wing airfoil and nacelle applications, wind tunnel testing, flight testing, missile aerodynamics, unsteady flow, configuration aerodynamics, and multiple body/interference flows. Attention is given to the numerical simulation of vortical flows over close-coupled canard-wing configuration, propulsive lift augmentation by side fences, road-vehicle aerodynamics, a shock-capturing method for multidimensional flow, transition-detection studies in a cryogenic environment, a three-dimensional Euler analysis of ducted propfan flowfields, multiple vortex and shock interaction at subsonic and supersonic speeds, and a Navier-Stokes simulation of waverider flowfields. Also discussed are the induced drag of crescent-shaped wings, the preliminary design aerodynamics of missile inlets, finite wing lift prediction at high angles-of-attack, optimal supersonic/hypersonic bodies, and adaptive grid embedding for the two-dimensional Euler equations

  9. 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.

  10. Generic hypersonic vehicle performance model

    Science.gov (United States)

    Chavez, Frank R.; Schmidt, David K.

    1993-01-01

    An integrated computational model of a generic hypersonic vehicle was developed for the purpose of determining the vehicle's performance characteristics, which include the lift, drag, thrust, and moment acting on the vehicle at specified altitude, flight condition, and vehicular configuration. The lift, drag, thrust, and moment are developed for the body fixed coordinate system. These forces and moments arise from both aerodynamic and propulsive sources. SCRAMjet engine performance characteristics, such as fuel flow rate, can also be determined. The vehicle is assumed to be a lifting body with a single aerodynamic control surface. The body shape and control surface location are arbitrary and must be defined. The aerodynamics are calculated using either 2-dimensional Newtonian or modified Newtonian theory and approximate high-Mach-number Prandtl-Meyer expansion theory. Skin-friction drag was also accounted for. The skin-friction drag coefficient is a function of the freestream Mach number. The data for the skin-friction drag coefficient values were taken from NASA Technical Memorandum 102610. The modeling of the vehicle's SCRAMjet engine is based on quasi 1-dimensional gas dynamics for the engine diffuser, nozzle, and the combustor with heat addition. The engine has three variable inputs for control: the engine inlet diffuser area ratio, the total temperature rise through the combustor due to combustion of the fuel, and the engine internal expansion nozzle area ratio. The pressure distribution over the vehicle's lower aft body surface, which acts as an external nozzle, is calculated using a combination of quasi 1-dimensional gas dynamic theory and Newtonian or modified Newtonian theory. The exhaust plume shape is determined by matching the pressure inside the plume, calculated from the gas dynamic equations, with the freestream pressure, calculated from Newtonian or Modified Newtonian theory. In this manner, the pressure distribution along the vehicle after body

  11. 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.

  12. 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.

  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. 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.

  15. Heading Control System for a Multi-body Vehicle with a Virtual Test Driver

    Directory of Open Access Journals (Sweden)

    POSTALCIOGLU OZGEN, S.

    2010-08-01

    Full Text Available This paper includes a Heading Control (HC system for a multi-body vehicle. HC system helps reducing the required torque from the driver and improves the lane keeping efficiency. HC system is important for safety and driver comfort in traffic. The controller performance is examined on a virtual test drive platform. The optimal control theory is applied to HC system and examined on a curved path and under a side wind disturbance. Different assistance levels are applied to see the characteristics of the controller with different virtual test drivers. The results are analyzed based on three performance indices; lane keeping performance (LKP index, assist torque performance (ATP index and driver torque performance (DTP index. As seen from the results while using HC system the lateral displacement decreases as the lane keeping performance increases and the driver torque performance decreases as the assist torque performance increases.

  16. 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.)

  17. 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.

  18. 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.

  19. Aerodynamic Interference between Oscillating Lifting Surfaces and Fuselage. Part 4: Flapping and Pitching WingsLaws for Micro-Air Vehicles (MAV in Straight Flight

    Directory of Open Access Journals (Sweden)

    Valentin Adrian Jean BUTOESCU

    2014-09-01

    Full Text Available In the fourth article of our series we continue to deal with the calculation of the aerodynamic unsteady forces on lifting surfaces. Now we present some applications of the theory discussed in the previous papers to the study of flapping wings.

  20. 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.

  1. 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

  2. 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.

  3. A fuzzy based feature selection from independent component subspace for machine learning classification of microarray data.

    Science.gov (United States)

    Aziz, Rabia; Verma, C K; Srivastava, Namita

    2016-06-01

    Feature (gene) selection and classification of microarray data are the two most interesting machine learning challenges. In the present work two existing feature selection/extraction algorithms, namely independent component analysis (ICA) and fuzzy backward feature elimination (FBFE) are used which is a new combination of selection/extraction. The main objective of this paper is to select the independent components of the DNA microarray data using FBFE to improve the performance of support vector machine (SVM) and Naïve Bayes (NB) classifier, while making the computational expenses affordable. To show the validity of the proposed method, it is applied to reduce the number of genes for five DNA microarray datasets namely; colon cancer, acute leukemia, prostate cancer, lung cancer II, and high-grade glioma. Now these datasets are then classified using SVM and NB classifiers. Experimental results on these five microarray datasets demonstrate that gene selected by proposed approach, effectively improve the performance of SVM and NB classifiers in terms of classification accuracy. We compare our proposed method with principal component analysis (PCA) as a standard extraction algorithm and find that the proposed method can obtain better classification accuracy, using SVM and NB classifiers with a smaller number of selected genes than the PCA. The curve between the average error rate and number of genes with each dataset represents the selection of required number of genes for the highest accuracy with our proposed method for both the classifiers. ROC shows best subset of genes for both the classifier of different datasets with propose method. PMID:27081632

  4. Aerodynamic and thermal characteristics of modified raked-off blunted cone

    Science.gov (United States)

    Davies, C. B.; Park, C.

    1986-01-01

    One of the leading candidate concepts of aeroassisted orbital transfer vehicles incorporates an aerobrake in the shape of a raked-off ellipsoidally blunted elliptic cone. The present paper proposes modifying this geometry to a spherically blunted circular cone to avoid flow impingement on the afterbody. In addition, the vehicle components are arranged axially so that the vehicle is always aerodynamically stable and controllable. The Newtonian aerodynamic characteristics of the modified aerobrake geometry are determined and are shown to be nearly identical to those of the elliptic cone described above. Flight regimes and heat transfer rates, both convective and nonequilibrium radiative, are calculated using the most up-to-date methods. It is shown that the total heat transfer rates for a noncatalytic heat shield will remain below tolerable limits.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. Principal Component Analysis Based Feature Extraction, Morphological Edge Detection and Localization for Fast Iris Recognition

    Directory of Open Access Journals (Sweden)

    P. Ramamoorthy

    2012-01-01

    Full Text Available This study involves the Iris Localization based on morphological or set theory which is well in shape detection. Principal Component Analysis (PCA is used for preprocessing, in which the removal of redundant and unwanted data is done. Applications such as Median Filtering and Adaptive thresholding are used for handling the variations in lighting and noise. Features are extracted using Wavelet Packet Transform (WPT. Finally matching is performed using KNN. The proposed method is better than the previous method and is proved by the results of different parameters. The testing of the proposed algorithm was done using CASIA iris database (V1.0 and (V3.0.

  10. 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.

  11. 75 FR 49945 - In the Matter of Certain Hybrid Electric Vehicles and Components Thereof; Notice of Commission...

    Science.gov (United States)

    2010-08-16

    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION In the Matter of Certain Hybrid Electric Vehicles and Components Thereof; Notice of Commission... Paice LLC (``Paice'') of Bonita Springs, Florida. 74 FR. 52258-59 (Oct. 9, 2009). The complaint named...

  12. 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

  13. 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.

  14. Variance Component Quantitative Trait Locus Analysis for Body Weight Traits in Purebred Korean Native Chicken.

    Science.gov (United States)

    Cahyadi, Muhammad; Park, Hee-Bok; Seo, Dong-Won; Jin, Shil; Choi, Nuri; Heo, Kang-Nyeong; Kang, Bo-Seok; Jo, Cheorun; Lee, Jun-Heon

    2016-01-01

    Quantitative trait locus (QTL) is a particular region of the genome containing one or more genes associated with economically important quantitative traits. This study was conducted to identify QTL regions for body weight and growth traits in purebred Korean native chicken (KNC). F1 samples (n = 595) were genotyped using 127 microsatellite markers and 8 single nucleotide polymorphisms that covered 2,616.1 centi Morgan (cM) of map length for 26 autosomal linkage groups. Body weight traits were measured every 2 weeks from hatch to 20 weeks of age. Weight of half carcass was also collected together with growth rate. A multipoint variance component linkage approach was used to identify QTLs for the body weight traits. Two significant QTLs for growth were identified on chicken chromosome 3 (GGA3) for growth 16 to18 weeks (logarithm of the odds [LOD] = 3.24, Nominal p value = 0.0001) and GGA4 for growth 6 to 8 weeks (LOD = 2.88, Nominal p value = 0.0003). Additionally, one significant QTL and three suggestive QTLs were detected for body weight traits in KNC; significant QTL for body weight at 4 weeks (LOD = 2.52, nominal p value = 0.0007) and suggestive QTL for 8 weeks (LOD = 1.96, Nominal p value = 0.0027) were detected on GGA4; QTLs were also detected for two different body weight traits: body weight at 16 weeks on GGA3 and body weight at 18 weeks on GGA19. Additionally, two suggestive QTLs for carcass weight were detected at 0 and 70 cM on GGA19. In conclusion, the current study identified several significant and suggestive QTLs that affect growth related traits in a unique resource pedigree in purebred KNC. This information will contribute to improving the body weight traits in native chicken breeds, especially for the Asian native chicken breeds. PMID:26732327

  15. 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...

  16. 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

  17. 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

  18. 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 ...

  19. Drive component for vehicles with an electric motor and an internal combustion engine. Antriebsbaugruppe fuer Kraftfahrzeuge mit einem Elektromotor und einem Verbrennungsmotor

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, H.

    1983-06-30

    Drive component for vehicles with an electric motor, which works on the driving axle of the vehicle and with an internal combustion engine working on the shaft of the electric motor via a clutch, which can be disconnected. There is a gearbox with an associated starting and circuit clutch in the unit between the electric motor and the driving axle of the vehicle.

  20. Multi-Center MRI Carotid Plaque Component Segmentation Using Feature Normalization and Transfer Learning.

    Science.gov (United States)

    van Engelen, Arna; van Dijk, Anouk C; Truijman, Martine T B; Van't Klooster, Ronald; van Opbroek, Annegreet; van der Lugt, Aad; Niessen, Wiro J; Kooi, M Eline; de Bruijne, Marleen

    2015-06-01

    Automated segmentation of plaque components in carotid artery magnetic resonance imaging (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, have shown good performance. However, a disadvantage of supervised methods is their reduced performance on data different from the training data, for example on images acquired with different scanners. Reducing the amount of manual annotations required for each new dataset will facilitate widespread implementation of supervised methods. In this paper we segment carotid plaque components of clinical interest (fibrous tissue, lipid tissue, calcification and intraplaque hemorrhage) in a multi-center MRI study. We perform voxelwise tissue classification by traditional same-center training, and compare results with two approaches that use little or no annotated same-center data. These approaches additionally use an annotated set of different-center data. We evaluate 1) a nonlinear feature normalization approach, and 2) two transfer-learning algorithms that use same and different-center data with different 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 same-center 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. PMID:25532205

  1. 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

  2. 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.

  3. 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.

  4. Size effects on insect hovering aerodynamics: an integrated computational study

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H [Graduate School of Engineering, Chiba University, Chiba, 263-8522 (Japan); Aono, H [Department of Aerospace Engineering, University of Michigan, Ann Arbor, MI48109 (United States)], E-mail: hliu@faculty.chiba-u.jp, E-mail: aonoh@umich.edu

    2009-03-01

    Hovering is a miracle of insects that is observed for all sizes of flying insects. Sizing effect in insect hovering on flapping-wing aerodynamics is of interest to both the micro-air-vehicle (MAV) community and also of importance to comparative morphologists. In this study, we present an integrated computational study of such size effects on insect hovering aerodynamics, which is performed using a biology-inspired dynamic flight simulator that integrates the modelling of realistic wing-body morphology, the modelling of flapping-wing and body kinematics and an in-house Navier-Stokes solver. Results of four typical insect hovering flights including a hawkmoth, a honeybee, a fruit fly and a thrips, over a wide range of Reynolds numbers from O(10{sup 4}) to O(10{sup 1}) are presented, which demonstrate the feasibility of the present integrated computational methods in quantitatively modelling and evaluating the unsteady aerodynamics in insect flapping flight. Our results based on realistically modelling of insect hovering therefore offer an integrated understanding of the near-field vortex dynamics, the far-field wake and downwash structures, and their correlation with the force production in terms of sizing and Reynolds number as well as wing kinematics. Our results not only give an integrated interpretation on the similarity and discrepancy of the near- and far-field vortex structures in insect hovering but also demonstrate that our methods can be an effective tool in the MAVs design.

  5. Size effects on insect hovering aerodynamics: an integrated computational study

    International Nuclear Information System (INIS)

    Hovering is a miracle of insects that is observed for all sizes of flying insects. Sizing effect in insect hovering on flapping-wing aerodynamics is of interest to both the micro-air-vehicle (MAV) community and also of importance to comparative morphologists. In this study, we present an integrated computational study of such size effects on insect hovering aerodynamics, which is performed using a biology-inspired dynamic flight simulator that integrates the modelling of realistic wing-body morphology, the modelling of flapping-wing and body kinematics and an in-house Navier-Stokes solver. Results of four typical insect hovering flights including a hawkmoth, a honeybee, a fruit fly and a thrips, over a wide range of Reynolds numbers from O(104) to O(101) are presented, which demonstrate the feasibility of the present integrated computational methods in quantitatively modelling and evaluating the unsteady aerodynamics in insect flapping flight. Our results based on realistically modelling of insect hovering therefore offer an integrated understanding of the near-field vortex dynamics, the far-field wake and downwash structures, and their correlation with the force production in terms of sizing and Reynolds number as well as wing kinematics. Our results not only give an integrated interpretation on the similarity and discrepancy of the near- and far-field vortex structures in insect hovering but also demonstrate that our methods can be an effective tool in the MAVs design

  6. A connected component-based method for efficiently integrating multiscale $N$-body systems

    OpenAIRE

    Jänes, Jürgen; Pelupessy, Federico I.; Zwart, Simon F. Portegies

    2014-01-01

    We present a novel method for efficient direct integration of gravitational N-body systems with a large variation in characteristic time scales. The method is based on a recursive and adaptive partitioning of the system based on the connected components of the graph generated by the particle distribution combined with an interaction-specific time step criterion. It uses an explicit and approximately time-symmetric time step criterion, and conserves linear and angular momentum to machine preci...

  7. Body Composition Features Predict Overall Survival in Patients With Hepatocellular Carcinoma

    Science.gov (United States)

    Singal, Amit G; Zhang, Peng; Waljee, Akbar K; Ananthakrishnan, Lakshmi; Parikh, Neehar D; Sharma, Pratima; Barman, Pranab; Krishnamurthy, Venkataramu; Wang, Lu; Wang, Stewart C; Su, Grace L

    2016-01-01

    Objectives: Existing prognostic models for patients with hepatocellular carcinoma (HCC) have limitations. Analytic morphomics, a novel process to measure body composition using computational image-processing algorithms, may offer further prognostic information. The aim of this study was to develop and validate a prognostic model for HCC patients using body composition features and objective clinical information. Methods: Using computed tomography scans from a cohort of HCC patients at the VA Ann Arbor Healthcare System between January 2006 and December 2013, we developed a prognostic model using analytic morphomics and routine clinical data based on multivariate Cox regression and regularization methods. We assessed model performance using C-statistics and validated predicted survival probabilities. We validated model performance in an external cohort of HCC patients from Parkland Hospital, a safety-net health system in Dallas County. Results: The derivation cohort consisted of 204 HCC patients (20.1% Barcelona Clinic Liver Cancer classification (BCLC) 0/A), and the validation cohort had 225 patients (22.2% BCLC 0/A). The analytic morphomics model had good prognostic accuracy in the derivation cohort (C-statistic 0.80, 95% confidence interval (CI) 0.71–0.89) and external validation cohort (C-statistic 0.75, 95% CI 0.68–0.82). The accuracy of the analytic morphomics model was significantly higher than that of TNM and BCLC staging systems in derivation (P<0.001 for both) and validation (P<0.001 for both) cohorts. For calibration, mean absolute errors in predicted 1-year survival probabilities were 5.3% (90% quantile of 7.5%) and 7.6% (90% quantile of 12.5%) in the derivation and validation cohorts, respectively. Conclusion: Body composition features, combined with readily available clinical data, can provide valuable prognostic information for patients with newly diagnosed HCC. PMID:27228403

  8. 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.

  9. 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

    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......, have shown good performance. However, a disadvantage of supervised methods is their reduced performance on data different from the training data, for example on images acquired with different scanners. Reducing the amount of manual annotations required for each new dataset will facilitate widespread...... with two approaches that use little or no annotated same-center data. These approaches additionally use an annotated set of differentcenter data. We evaluate 1) a non-linear feature normalization approach, and 2) two transfer-learning algorithms that use same and different-center data with different...

  10. 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.

  11. 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.

  12. Special features of the composition and chemical structure of green pigments - anomalous components of petroleum vanadylporphyrins

    Energy Technology Data Exchange (ETDEWEB)

    Pevneva, G.S.; Zemtseva, L.I.; Antipenko, V.R.; Titov, V.I.

    1985-01-01

    Investigations covering two decades, in the field of minerals, including petroleum porphyrins has widened considerably our understanding of their group composition and special features of their chemical structure. In addition to members of the basic homologous series (alkylporphyrins (series M) and cycloalkano-porphyrins (series M-2)), two groups of green porphyrins were found with spectroscopic properties very different from those of petroleum vanadylporphyrins and other bituminous components of sedimentary rocks. These compounds are, usually, contained in increased proportions in high and low-polarity fractions of petroleum vanadylporphyrin concentrates. Experimental data reported by other workers and from our previous study confirm that the combination of a carbonyl group with a quasi-aromatic porphyin macroring system, is a distinctive feature of the structure of the polar green pigment group. Some new data are presented here which confirm this point of view, however, the work is devoted mainly to the separation and study of another group of green pigments, concentrated in the least polar fraction from chromatographic separation of petroleum vanadylporphyrins. This group of green pigments has been reported previously as compounds of a minor homologous series of rhodoporphyrins of petroleum deposits (petroleum rhodophorphyrins).

  13. 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

  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. Discrete vortex method simulations of aerodynamic admittance in bridge aerodynamics

    DEFF Research Database (Denmark)

    Rasmussen, Johannes Tophøj; Hejlesen, Mads Mølholm; Larsen, Allan; Walther, Jens Honore

    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...

  16. BREN: Body Reflection Essence-Neuter Model for Separation of Reflection Components

    CERN Document Server

    Je, Changsoo

    2015-01-01

    We propose a novel reflection color model consisting of body essence and (mixed) neuter, and present an effective method for separating dichromatic reflection components using a single image. Body essence is an entity invariant to interface reflection, and has two degrees of freedom unlike hue and maximum chromaticity. As a result, the proposed method is insensitive to noise and proper for colors around CMY (cyan, magenta, and yellow) as well as RGB (red, green, and blue), contrary to the maximum chromaticity-based methods. Interface reflection is separated by using a Gaussian function, which removes a critical thresholding problem. Furthermore, the method does not require any region segmentation. Experimental results show the efficacy of the proposed model and method.

  17. Combining features from ERP components in single-trial EEG for discriminating four-category visual objects

    Science.gov (United States)

    Wang, Changming; Xiong, Shi; Hu, Xiaoping; Yao, Li; Zhang, Jiacai

    2012-10-01

    Categorization of images containing visual objects can be successfully recognized using single-trial electroencephalograph (EEG) measured when subjects view images. Previous studies have shown that task-related information contained in event-related potential (ERP) components could discriminate two or three categories of object images. In this study, we investigated whether four categories of objects (human faces, buildings, cats and cars) could be mutually discriminated using single-trial EEG data. Here, the EEG waveforms acquired while subjects were viewing four categories of object images were segmented into several ERP components (P1, N1, P2a and P2b), and then Fisher linear discriminant analysis (Fisher-LDA) was used to classify EEG features extracted from ERP components. Firstly, we compared the classification results using features from single ERP components, and identified that the N1 component achieved the highest classification accuracies. Secondly, we discriminated four categories of objects using combining features from multiple ERP components, and showed that combination of ERP components improved four-category classification accuracies by utilizing the complementarity of discriminative information in ERP components. These findings confirmed that four categories of object images could be discriminated with single-trial EEG and could direct us to select effective EEG features for classifying visual objects.

  18. Obsessive-compulsive disorder and body dysmorphic disorder: a comparison of clinical features.

    Science.gov (United States)

    Frare, Franco; Perugi, Giulio; Ruffolo, Giuseppe; Toni, Cristina

    2004-08-01

    Body dysmorphic disorder (BDD) is currently classified as a somatoform disorder in DSM-IV, but has been long noted to have some important similarities with obsessive-compulsive disorder (OCD). In addition, BDD and OCD have been often reported to be comorbid with each other. In the present study, we compared demographic characteristics, clinical features and psychiatric comorbidity in patients with OCD, BDD or comorbid BDD-OCD (34 subjects with BDD, 79 with OCD and 24 with BDD-OCD). We also compared the pattern of body dysmorphic concerns and associated behaviors in BDD patients with or without OCD comorbidity. In our sample, BDD and OCD groups showed similar sex ratio. Both groups with BDD and BDD-OCD were significantly younger, and experienced the onset of their disorder at a significantly younger age than subjects with OCD. The two BDD groups were also less likely to be married, and more likely to be unemployed and to have achieved lower level degree, than OCD subjects even when controlling for age. The three groups were significantly different in the presence of comorbid bulimia, alcohol-related and substance-use disorders, BDD-OCD patients showing the highest rate and OCD the lowest. BDD-OCD reported more comorbid bipolar II disorder and social phobia than in the other two groups, while generalized anxiety disorder was observed more frequently in OCD patients. Patients with BDD and BDD-OCD were similar as regards the presence of repetitive BDD-related behaviors, such as mirror-checking or camouflaging. Both groups also did show a similar pattern of distribution as regards the localization of the supposed physical defects in specific areas of the body. The only significant difference concerned the localization in the face, that was more frequent in the BDD group. Our results do not contradict the proposed possible conceptualization of BDD as an OCD spectrum disorder. However, BDD does not appear to be a simple clinical variant of OCD and it seems to be also

  19. Two Independent Mushroom Body Output Circuits Retrieve the Six Discrete Components of Drosophila Aversive Memory

    OpenAIRE

    Emna Bouzaiane; Séverine Trannoy; Lisa Scheunemann; Pierre-Yves Plaçais; Thomas Preat

    2015-01-01

    Understanding how the various memory components are encoded and how they interact to guide behavior requires knowledge of the underlying neural circuits. Currently, aversive olfactory memory in Drosophila is behaviorally subdivided into four discrete phases. Among these, short- and long-term memories rely, respectively, on the γ and α/β Kenyon cells (KCs), two distinct subsets of the ∼2,000 neurons in the mushroom body (MB). Whereas V2 efferent neurons retrieve memory from α/β KCs, the neuron...

  20. 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

  1. The Promise of Fuel-Cell Vehicles

    OpenAIRE

    Deluchi, Mark; Swan, David

    1993-01-01

    In 1990 General Motors unveiled a new battery-powered electric vehicle, called the Impact - the flashiest, best-engineered electric vehicle ever. Thanks to an advanced electric drivetrain and a light-weight aerodynamic, energy-conserving body, the Impact accelerates faster than comparable gasoline-powered cars. However, even under the best conditions, despite its advanced technology and its state-of-the-art lead-acid battery, it will go no more than 120 miles and, as with all battery-powered ...

  2. 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.

  3. Aerodynamic design on high-speed trains

    Science.gov (United States)

    Ding, San-San; Li, Qiang; Tian, Ai-Qin; Du, Jian; Liu, Jia-Li

    2016-04-01

    Compared with the traditional train, the operational speed of the high-speed train has largely improved, and the dynamic environment of the train has changed from one of mechanical domination to one of aerodynamic domination. The aerodynamic problem has become the key technological challenge of high-speed trains and significantly affects the economy, environment, safety, and comfort. In this paper, the relationships among the aerodynamic design principle, aerodynamic performance indexes, and design variables are first studied, and the research methods of train aerodynamics are proposed, including numerical simulation, a reduced-scale test, and a full-scale test. Technological schemes of train aerodynamics involve the optimization design of the streamlined head and the smooth design of the body surface. Optimization design of the streamlined head includes conception design, project design, numerical simulation, and a reduced-scale test. Smooth design of the body surface is mainly used for the key parts, such as electric-current collecting system, wheel truck compartment, and windshield. The aerodynamic design method established in this paper has been successfully applied to various high-speed trains (CRH380A, CRH380AM, CRH6, CRH2G, and the Standard electric multiple unit (EMU)) that have met expected design objectives. The research results can provide an effective guideline for the aerodynamic design of high-speed trains.

  4. 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

  5. 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.

  6. An Adaptive System for Load Relief and Accurate Control of Launch Vehicles

    Science.gov (United States)

    Klenk, W. J.

    1964-01-01

    An adaptive load relief control system for a SATURN type vehicle which significantly reduces aerodynamically induced structural loads without incurring excessive velocity dispersions has been studied. This control system utilizes pendulous accelerometers to measure the angle between the total vehicle acceleration vector and the vehicle body. This measurement is used to fly the vehicle along the nominal trajectory to minimize velocity dispersions. However, if unusually high values of wind velocity are encountered, the system will cause the vehicle to turn into the wind to reduce the lateral structural loads. Results of an anal6g computer study show that the adaptive system can reduce aerodynam3cally induced peak structural loads as much as 50 percent under those encountered using conventional control techniques. relief is used only when required, velocity dispersions are held to a minimum.

  7. 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....

  8. 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.

  9. 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)

  10. 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.

  11. 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.

  12. Prenatal ultrasonographical features of limb body wall complex: a review of etiopathogenesis and a new classification.

    Science.gov (United States)

    Sahinoglu, Zeki; Uludogan, Mehmet; Arik, Huseyin; Aydin, Arzu; Kucukbas, Mehmet; Bilgic, Remziye; Toksoy, Guven

    2007-01-01

    Limb body wall complex is a spectrum of multiple severe anomalies. The etiopathogenesis and clinical classification are still under discussion. In our article, while reviewing previous etiopathogenetical hypothesis, we propose a new clinical classification regarding embryological theories and pheneotypical features. According to the Van Allen diagnostic criteria, the findings of 6 affected fetuses are presented. Prenatal diagnosis was performed in 5 of 6 cases. Craniofacial malformations were present in only 1 case. Thoracic defect and abdominoschisis (either infraumbilical or supraumbilical) associated with visceral eventration, placental-umbilical cord anomalies, and limb defects were detected in the other 5 cases. Aberrant development of each of the 4 embryonic folds (cephalic, 2 lateral abdominal, and caudal) associated with faulty umbilical ring development and placental formation were considered responsible for development of various malformations. In previous clinical classifications, existence or absence of the craniofacial malformation was utilized as an unique discriminating criterion while multiple anomalies exist. In this report, we propose a new clinical classification concerning almost all anomalies caused by defective placental attachment and maldevelopment of the 4 folds. PMID:17886024

  13. 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.

  14. 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...

  15. 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)

  16. 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.

  17. 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.

  18. 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.

  19. FeatureViewer, a BioJS component for visualization of position-based annotations in protein sequences

    OpenAIRE

    Leyla Garcia; Guy Yachdav; Maria-Jesus Martin

    2014-01-01

    Summary: FeatureViewer is a BioJS component that lays out, maps, orients, and renders position-based annotations for protein sequences. This component is highly flexible and customizable, allowing the presentation of annotations by rows, all centered, or distributed in non-overlapping tracks. It uses either lines or shapes for sites and rectangles for regions. The result is a powerful visualization tool that can be easily integrated into web applications as well as documents as it provides an...

  20. 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.

  1. 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...

  2. Finite-volume modelling of heat and mass transfer during convective drying of porous bodies - Non-conjugate and conjugate formulations involving the aerodynamic effects

    Energy Technology Data Exchange (ETDEWEB)

    Lamnatou, Chr.; Papanicolaou, E.; Belessiotis, V. [Solar and other Energy Systems Lab., Institute of Nuclear Technology and Radiation Protection, National Center for Scientific Research ' ' Demokritos' ' , Aghia Paraskevi, 15310 Athens (Greece); Kyriakis, N. [Process Equipment Design Lab., Mechanical Engineering Dept., School of Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

    2010-07-15

    In this study, a numerical procedure is outlined and representative results for heat and mass transfer during convective drying of porous bodies are presented. The Luikov model was implemented and applied both on individual samples of construction materials and agricultural products, as well as on a drying-chamber scale, with parallel flow of a hot air stream over rectangular slabs which represent the product to be dried. In the latter case the configuration is an experimental dryer in which the heat source is a solar air collector with evacuated tubes. A general approach was developed that allows a selection between modelling of phenomena either in the drying solid only, or considering an extended simulation domain encompassing, apart from the solid body, the flow of air as well. In the second case, the solution of the flow field is pursued along with a conjugate heat/mass transfer problem coupling the solid and fluid phenomena and in both cases phase change (evaporation) was taken into account. For the numerical simulation, the finite-volume method was used. The validation of the model was based on experimental and numerical results from the literature and results from simulations that were conducted in the pursuit of the energetic optimization of an experimental solar dryer of NCSR ''Demokritos'' are presented. In the latter case, the effect of the particular flow field features developing for a single and a double-plate configuration on the heat/mass transport and drying rates is demonstrated. Such a methodology could be used to analyze the transport phenomena in any type of convective dryer, including those utilizing solar energy as the heat source. (author)

  3. 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.

  4. Rocket Sled Propelled Testing of a Supersonic Inflatable Aerodynamic Decelerator

    Science.gov (United States)

    Meacham, Michael B.; Kennett, Andrew; Townsend, Derik J.; Marti, Benjamin

    2013-01-01

    Decelerators (IADs) have traditionally been tested in wind tunnels. As the limitations of these test facilities are reached, other avenues must be pursued. The IAD being tested is a Supersonic IAD (SIAD), which attaches just aft of the heatshield around the perimeter of an entry body. This 'attached torus' SIAD is meant to improve the accuracy of landing for robotic class missions to Mars and allow for potentially increased payloads. The SIAD Design Verification (SDV) test aims to qualify the SIAD by applying a targeted aerodynamic load to the vehicle. While many test architectures were researched, a rocket sled track was ultimately chosen to be the most cost effective way to achieve the desired dynamic pressures. The Supersonic Naval Ordnance Research Track (SNORT) at the Naval Air Warfare Center Weapons Division (NAWCWD) China Lake is a four mile test track, traditionally used for warhead and ejection seat testing. Prior to SDV, inflatable drag bodies have been tested on this particular track. Teams at Jet Propulsion Laboratory (JPL) and NAWCWD collaborate together to design and fabricate one of the largest sleds ever built. The SDV sled is comprised of three individual sleds: a Pusher Sled which holds the solid booster rockets, an Item Sled which supports the test vehicle, and a Camera Sled that is pushed in front for in-situ footage and measurements. The JPL-designed Test Vehicle has a full-scale heatshield shape and contains all instrumentation and inflation systems necessary to inflate and test a SIAD. The first campaign that is run at SNORT tested all hardware and instrumentation before the SIAD was ready to be tested. For each of the three tests in this campaign, the number of rockets and top speed was increased and the data analyzed to ensure the hardware is safe at the necessary accelerations and aerodynamic loads.

  5. Different cerebral metabolic features in dementia with lewy bodies with/without visual hallucination

    International Nuclear Information System (INIS)

    Reduction of glucose metabolism in the occipital cortex is well known in dementia with Lewy Bodies (DLB). The aim of this study was to evaluate the different nature of FDG PET in DLB patients who had visual hallucination or not. Thirteen patients (729 yrs, m:f=6:7) with DLB participated. DLB patient were classified into two groups according to the presence of visual hallucination; seven DLB patients with visual hallucination and 6 patients without visual hallucination. No differences between patient with and without visual hallucination was found in their cognitive function measured by mini mental status exam (MMSE) and clinical dementia rating (CDR) scale. Age and gender matched 30 healthy subjects (age; 715 yrs, m: f = 13:17) served as controls for comparison purpose. Regional metabolic differences on FDG PET among the groups were tested using SPM. In DLB patients groups regardless of visual hallucination, significant regional hypometabolism were observed in the bilateral occipital cortices as well as bilateral parietotemporal and frontal association cortices when compared with healthy controls, as expected. In DLB patients with visual hallucination compared to patients without hallucination, regional hypometabolism over primary and secondary visual cortex (BA17, BA18) was more significant. Moreover, lower regional metabolism in the paracentral area (BA 6) and cerebellar vermis was also observed in DLB with visual hallucination than without hallucination. Profound hypometabolism in the visual cortex may be a feature in DLB patients with visual hallucination. Also, relative hypometabolism in the paracentral area and cerebellum could be neurobiological characteristics related with abnormal cognitive and motor process response to hallucination

  6. Different cerebral metabolic features in dementia with lewy bodies with/without visual hallucination

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bom Sahn; Kim, Yu Kyeong; Yang, Young Soon; Park, Eun Kyung; Cho, Sang Soo; Kim, Sang Yun; Kim, Sang Eun [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2007-07-01

    Reduction of glucose metabolism in the occipital cortex is well known in dementia with Lewy Bodies (DLB). The aim of this study was to evaluate the different nature of FDG PET in DLB patients who had visual hallucination or not. Thirteen patients (729 yrs, m:f=6:7) with DLB participated. DLB patient were classified into two groups according to the presence of visual hallucination; seven DLB patients with visual hallucination and 6 patients without visual hallucination. No differences between patient with and without visual hallucination was found in their cognitive function measured by mini mental status exam (MMSE) and clinical dementia rating (CDR) scale. Age and gender matched 30 healthy subjects (age; 715 yrs, m: f = 13:17) served as controls for comparison purpose. Regional metabolic differences on FDG PET among the groups were tested using SPM. In DLB patients groups regardless of visual hallucination, significant regional hypometabolism were observed in the bilateral occipital cortices as well as bilateral parietotemporal and frontal association cortices when compared with healthy controls, as expected. In DLB patients with visual hallucination compared to patients without hallucination, regional hypometabolism over primary and secondary visual cortex (BA17, BA18) was more significant. Moreover, lower regional metabolism in the paracentral area (BA 6) and cerebellar vermis was also observed in DLB with visual hallucination than without hallucination. Profound hypometabolism in the visual cortex may be a feature in DLB patients with visual hallucination. Also, relative hypometabolism in the paracentral area and cerebellum could be neurobiological characteristics related with abnormal cognitive and motor process response to hallucination.

  7. 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...

  8. 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.

  9. 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.

  10. SOFA 2.0: Balancing Advanced Features in a Hierarchical Component Model

    Czech Academy of Sciences Publication Activity Database

    Bureš, Tomáš; Hnětynka, P.; Plášil, František

    Los Alamitos : IEEE CS, 2006, s. 40-48. ISBN 0-7695-2656-X. [SERA 2006. Seattle (US), 09.08.2006-11.08.2006] R&D Projects: GA ČR GA201/06/0770 Institutional research plan: CEZ:AV0Z10300504 Keywords : component systems * component development * software connectors * SOA Subject RIV: JC - Computer Hardware ; Software

  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. 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 %.

  13. A large-scale computer facility for computational aerodynamics

    International Nuclear Information System (INIS)

    The combination of computer system technology and numerical modeling have advanced to the point that computational aerodynamics has emerged as an essential element in aerospace vehicle design methodology. To provide for further advances in modeling of aerodynamic flow fields, NASA has initiated at the Ames Research Center the Numerical Aerodynamic Simulation (NAS) Program. The objective of the Program is to develop a leading-edge, large-scale computer facility, and make it available to NASA, DoD, other Government agencies, industry and universities as a necessary element in ensuring continuing leadership in computational aerodynamics and related disciplines. The Program will establish an initial operational capability in 1986 and systematically enhance that capability by incorporating evolving improvements in state-of-the-art computer system technologies as required to maintain a leadership role. This paper briefly reviews the present and future requirements for computational aerodynamics and discusses the Numerical Aerodynamic Simulation Program objectives, computational goals, and implementation plans

  14. Contribution of individual components of a job cycle on overall severity of whole-body vibration exposure: a study in Indian mines.

    Science.gov (United States)

    Mandal, Bibhuti B; Mansfield, Neil J

    2016-01-01

    Drivers of earth-moving machines are exposed to whole-body vibration (WBV). In mining operations there can be a combination of relatively high magnitudes of vibration and long exposure times. Effective risk mitigation requires understanding of the main aspects of a task that pose a hazard to health. There are very few published studies of WBV exposure from India. This paper reports on a study that considered the contribution of the component phases of dumper operations, on the overall vibration exposure of the drivers. It shows that vibration magnitudes are relatively high, and that haulage tasks are the main contributor to the exposure. It is recommended that driver speed, haul road surfaces and vehicle maintenance/selection are optimized to ensure minimization of vibration. If this is not sufficient, operation times might need to be reduced in order to ensure that the health guidance caution zone from Standard No. ISO 2631-1:1997 is not exceeded. PMID:26652833

  15. Earth moving machine whole-body vibration and the contribution of Sub-1Hz components to ISO 2631-1 metrics.

    Science.gov (United States)

    Mansfield, Neil J; Newell, Geraldine S; Notini, Luca

    2009-08-01

    Exposure to whole-body vibration (WBV) is an occupational hazard for operators of industrial vehicles, such as earth-moving machines. Quantification of WBV exposure in terms of impact on health forms one aspect of the Standard ISO 2631-1 (1997). Regarding assessment of risk to health, ISO 2631-1 (1997) states that if WBV components below 1 Hz are not ;relevant nor important' then they can be excluded from the assessment. In this paper the influence of sub-1 Hz components in WBV acquired from a sample of 46 earth moving machines is evaluated in terms of their contribution to ISO 2631-1 WBV exposure dose metrics: frequency weighted r.m.s. and the vibration dose value (VDV). For the majority of machines, a high proportion of the horizontal (x- and y-axis) WBV r.m.s. and VDV values was generated by sub-1 Hz vibration components; there was a much lower proportion of the vertical (z-axis) vibration generated by such components. PMID:19672014

  16. 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.

  17. 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.

  18. 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.... Lubricant. II. Fuel System. (1) Fuel type. (2) Fuel pump. (3) Fuel filters. (4) Injectors. (5) Governor. III... Components. (1) Carburetor air cleaner filter. (2) Hot air control valve. (b) Diesel Light-Duty......

  19. 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.

  20. 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...

  1. 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.

  2. Aerodynamic Ground Effect in Fruitfly Sized Insect Takeoff

    Science.gov (United States)

    Kolomenskiy, Dmitry; Maeda, Masateru; Engels, Thomas; Liu, Hao; Schneider, Kai; Nave, Jean-Christophe

    2016-01-01

    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. PMID:27019208

  3. 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.

  4. 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.

  5. 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)

  6. 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...

  7. 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.

  8. Wavelet Correlation Feature Scale Entropy and Fuzzy Support Vector Machine Approach for Aeroengine Whole-Body Vibration Fault Diagnosis

    OpenAIRE

    Cheng-Wei Fei; Guang-Chen Bai

    2013-01-01

    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...

  9. 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)

  10. 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

  11. 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.

  12. 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...

  13. 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.

  14. Multiple-body simulation with emphasis on integrated Space Shuttle vehicle

    Science.gov (United States)

    Chiu, Ing-Tsau

    1993-01-01

    The program to obtain intergrid communications - Pegasus - was enhanced to make better use of computing resources. Periodic block tridiagonal and penta-diagonal diagonal routines in OVERFLOW were modified to use a better algorithm to speed up the calculation for grids with periodic boundary conditions. Several programs were added to collar grid tools and a user friendly shell script was developed to help users generate collar grids. User interface for HYPGEN was modified to cope with the changes in HYPGEN. ET/SRB attach hardware grids were added to the computational model for the space shuttle and is currently incorporated into the refined shuttle model jointly developed at Johnson Space Center and Ames Research Center. Flow simulation for the integrated space shuttle vehicle at flight Reynolds number was carried out and compared with flight data as well as the earlier simulation for wind tunnel Reynolds number.

  15. Thermodynamics of the vehicle. 2. ed.; Thermodynamik des Kraftfahrzeugs

    Energy Technology Data Exchange (ETDEWEB)

    Stan, Cornel [California Univ., Berkeley, CA (United States); Paris Univ., 75 (France); Pisa Univ. (Italy); Perugia Univ. (Italy); Kronstadt Univ. (Russian Federation)

    2012-07-01

    The vehicle is characterized by thermodynamic processes at almost all levels: Drive systems (from internal combustion engines and hybrids to electric motors with fuel cells), charging, cooling and heating circuits, air conditioners, aerodynamics of the vehicle body, damper systems, fuel injection systems, exhaust systems, brakes, tires. However, due to an enhanced complexity and phenomenological approach the thermodynamics is a challenge for engineers. This book under considerations combines the theoretical principles and their mathematical presentation with applications in the automotive technology. Numerous specific examples facilitate the understanding and practical application of the basic knowledge. In addition to corrections and updates, the new edition under consideration contains more practical exercises and in-depth questions.

  16. Processing conditions and microstructural features of porous 316L stainless steel components by DMLS

    International Nuclear Information System (INIS)

    Direct metal laser sintering (DMLS), due to its flexibility in materials and shapes, would be especially interesting to produce complex shaped porous metallic components. In the present work, processing conditions and microstructural characteristics of direct laser sintered porous 316L stainless steel components were studied. It was found that a partial melting mechanism of powders gave a high feasibility in obtaining porous sintered structures possessing porosities of ∼21-∼55%. Linear energy density (LED), which was defined by the ratio of laser power to scan speed, was used to tailor the laser sintering mechanism. A moderate LED of ∼3400-∼6000 J/m and a lower scan speed less than 0.06 m/s proved to be feasible. With the favorable sintering mechanism prevailed, lowering laser power or increasing scan speed, scan line spacing, and powder layer thickness generally led to a higher porosity. Metallurgical mechanisms of pore formation during DMLS were addressed. It showed that the presence of pores was through: (i) the formation of liquid bridges between partially melted particles during laser irradiation; and (ii) the growth of sintering necks during solidification, leaving residual pores between solidified metallic agglomerates.

  17. A multi-attribute based methodology for vehicle detection and identification

    Science.gov (United States)

    Elangovan, Vinayak; Alsaidi, Bashir; Shirkhodaie, Amir

    2013-05-01

    Robust vehicle detection and identification is required for the intelligent persistent surveillance systems. In this paper, we present a Multi-attribute Vehicle Detection and Identification technique (MVDI) for detection and classification of stationary vehicles. The proposed model uses a supervised Hamming Neural Network (HNN) for taxonomy of shape of the vehicle. Vehicles silhouette features are employed for the training of the HNN from a large array of training vehicle samples in different type, scale, and color variation. Invariant vehicle silhouette attributes are used as features for training of the HNN which is based on an internal Hamming Distance and shape features to determine degree of similarity of a test vehicle against those it's selectively trained with. Upon detection of class of the vehicle, the other vehicle attributes such as: color and orientation are determined. For vehicle color detection, provincial regions of the vehicle body are used for matching color of the vehicle. For the vehicle orientation detection, the key structural features of the vehicle are extracted and subjected to classification based on color tune, geometrical shape, and tire region detection. The experimental results show the technique is promising and has robustness for detection and identification of vehicle based on their multi-attribute features. Furthermore this paper demonstrates the importance of the vehicle attributes detection towards the identification of Human-Vehicle Interaction events.

  18. 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

  19. 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…

  20. 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.

  1. The Two-Component Model for Calculating Total Body Fat from Body Density: An Evaluation in Healthy Women before, during and after Pregnancy

    Directory of Open Access Journals (Sweden)

    Elisabet Forsum

    2014-12-01

    Full Text Available A possibility to assess body composition during pregnancy is often important. Estimating body density (DB and use the two-component model (2CM to calculate total body fat (TBF represents an option. However, this approach has been insufficiently evaluated during pregnancy. We evaluated the 2CM, and estimated fat-free mass (FFM density and variability in 17 healthy women before pregnancy, in gestational weeks 14 and 32, and 2 weeks postpartum based on DB (underwater weighing, total body water (deuterium dilution and body weight, assessed on these four occasions. TBF, calculated using the 2CM and published FFM density (TBF2CM, was compared to reference estimates obtained using the three-component model (TBF3CM. TBF2CM minus TBF3CM (mean ± 2SD was −1.63 ± 5.67 (p = 0.031, −1.39 ± 7.75 (p = 0.16, −0.38 ± 4.44 (p = 0.49 and −1.39 ± 5.22 (p = 0.043 % before pregnancy, in gestational weeks 14 and 32 and 2 weeks postpartum, respectively. The effect of pregnancy on the variability of FFM density was larger in gestational week 14 than in gestational week 32. The 2CM, based on DB and published FFM density, assessed body composition as accurately in gestational week 32 as in non-pregnant adults. Corresponding values in gestational week 14 were slightly less accurate than those obtained before pregnancy.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Summary analysis of the Gemini entry aerodynamics

    Science.gov (United States)

    Whitnah, A. M.; Howes, D. B.

    1972-01-01

    The aerodynamic data that were derived in 1967 from the analysis of flight-generated data for the Gemini entry module are presented. These data represent the aerodynamic characteristics exhibited by the vehicle during the entry portion of Gemini 2, 3, 5, 8, 10, 11, and 12 missions. For the Gemini, 5, 8, 10, 11, and 12 missions, the flight-generated lift-to-drag ratios and corresponding angles of attack are compared with the wind tunnel data. These comparisons show that the flight generated lift-to-drag ratios are consistently lower than were anticipated from the tunnel data. Numerous data uncertainties are cited that provide an insight into the problems that are related to an analysis of flight data developed from instrumentation systems, the primary functions of which are other than the evaluation of flight aerodynamic performance.

  7. 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...

  8. Modelling physiological features of Human body behavior in car crash simulations

    OpenAIRE

    Behr, M.; GODIO,Y; LLARI,M; Brunet, C

    2007-01-01

    Human numerical models are widely used to investigate injury mechanisms involved in car crash configurations. One limitation of these models is linked to the time dependency of biological tissues mechanical properties, as a result of various physiological modifications. To answer this limitation, we present one possible approach to evaluate the influence of internal body pressures (mainly resulting from breathing) on the result of a frontal impact, by modelling main muscles responsible for re...

  9. 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.

  10. Chemical composition and structural features of the macromolecular components of plantation Acacia mangium wood.

    Science.gov (United States)

    Pinto, Paula C; Evtuguin, Dmitry V; Pascoal Neto, Carlos

    2005-10-01

    The wood of Acacia mangium, a prominent fast-growing plantation species used in the pulp-and-paper industry and, so far, poorly investigated for its chemical structure, was submitted to a detailed characterization of its main macromolecular components. Lignin (28% wood weight) isolated by mild acidolysis and characterized by permanganate oxidation, 1H and 13C NMR, and GPC, showed a very low content of syringylpropane-derived units (S:G:H of 48:49:3), a high degree of condensation, a low content of beta-O-4 ( approximately 0.40-0.43 per C6) structures, and a Mw of 2230. Glucuronoxylan (14% wood weight) isolated by alkaline (KOH) or by dimethyl sulfoxide extraction was characterized by methylation analysis, 1H NMR, and GPC. About 10% of the xylopyranose (Xylp) units constituting the linear backbone were substituted at O-2 with 4-O-methylglucuronic acid residues. Almost half of the Xylp units (45%) were O-2 (18%), O-3 (24%) or O-2,3 (3%) acetylated. X-ray diffraction analysis of cellulose (46% wood weight), isolated according to the Kürschner-Hoffer method, showed a degree of crystallinity of 67.6%. PMID:16190642

  11. Unsteady transonic aerodynamics

    International Nuclear Information System (INIS)

    Various papers on unsteady transonic aerodynamics are presented. The topics addressed include: physical phenomena associated with unsteady transonic flows, basic equations for unsteady transonic flow, practical problems concerning aircraft, basic numerical methods, computational methods for unsteady transonic flows, application of transonic flow analysis to helicopter rotor problems, unsteady aerodynamics for turbomachinery aeroelastic applications, alternative methods for modeling unsteady transonic flows

  12. 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.

  13. Many-body effects and excitonic features in 2D biphenylene carbon.

    Science.gov (United States)

    Lüder, Johann; Puglia, Carla; Ottosson, Henrik; Eriksson, Olle; Sanyal, Biplab; Brena, Barbara

    2016-01-14

    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. PMID:26772582

  14. 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

  15. Many-body effects and excitonic features in 2D biphenylene carbon

    Energy Technology Data Exchange (ETDEWEB)

    Lüder, Johann, E-mail: johann.luder@physics.uu.se; Puglia, Carla; Eriksson, Olle; Sanyal, Biplab; Brena, Barbara [Department of Physics and Astronomy, Uppsala University, P.O. Box 516, 751 20 Uppsala (Sweden); Ottosson, Henrik [Department of Chemistry–BMC, Uppsala University, P.O. Box 576, 751 23 Uppsala (Sweden)

    2016-01-14

    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.

  16. Using Unmanned Aerial Vehicle (UAV) Imagery to Investigate Surface Displacements and Surface Features of the Super-Sauze Earthflow (France)

    Science.gov (United States)

    James, M. R.; Tizzard, S.; Niethammer, U.

    2014-12-01

    We present the result of using imagery collected with a small rotary wing UAV (unmanned aerial vehicle) to investigate surface displacements and fissures on the Super-Sauze earthflow (France); a slow moving earthflow with the potential to develop into rapid and highly destructive mud flows. UAV imagery acquired in October 2009 was processed using a structure-from-motion and multi-view stereo (SfM-MVS) approach in PhotoScan software. Identification of ~200 ground control points throughout the image set was facilitated by automated image matching in SfM_georef software[1] and the data incorporated into PhotoScan for network optimisation and georeferencing. The completed 2009 model enabled an ~5 cm spatial resolution orthoimage to be generated with an expected accuracy (based on residuals on control) of ~0.3 m. This was supported by comparison to a previously created 2008 model, which gave standard deviations on tie points (located on stationary terrain) of 0.27 m and 0.43 m in Easting and Northing respectively. The high resolution of the orthoimage allowed an investigation into surface displacements and geomorphology of surface features (compared to the 2008 model). The results have produced a comprehensive surface displacement map of the Super-Sauze earthflow, as well as highlighting interesting variations in fissure geomorphology and density between the 2008 and 2009 models. This study underscored the capability for UAV imagery and SfM-MVS to generate highly detailed orthographic imagery and DEMs with a low cost approach that offers significant potential for landslide hazard assessments. [1] http://www.lancaster.ac.uk/staff/jamesm/software/sfm_georef.htm

  17. 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)

  18. 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.

  19. Vision-based industrial automatic vehicle classifier

    Science.gov (United States)

    Khanipov, Timur; Koptelov, Ivan; Grigoryev, Anton; Kuznetsova, Elena; Nikolaev, Dmitry

    2015-02-01

    The paper describes the automatic motor vehicle video stream based classification system. The system determines vehicle type at payment collection plazas on toll roads. Classification is performed in accordance with a preconfigured set of rules which determine type by number of wheel axles, vehicle length, height over the first axle and full height. These characteristics are calculated using various computer vision algorithms: contour detectors, correlational analysis, fast Hough transform, Viola-Jones detectors, connected components analysis, elliptic shapes detectors and others. Input data contains video streams and induction loop signals. Output signals are vehicle enter and exit events, vehicle type, motion direction, speed and the above mentioned features.

  20. 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...

  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. 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…

  3. 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.)

  4. 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.

  5. 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

  6. 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. PMID:22701782

  7. [Genetic features of nitric oxide generating systems predetermine the body's resistance to the development of carcinoma].

    Science.gov (United States)

    Kalish, S V; Budanova, O P; Lyamina, S V; Malyshev, I Yu

    2015-01-01

    Predisposition to tumors is often determined by how effectively the genotype of an individual forms an immune defense. An important factor of such protection is macrophage NO. We assumed that the body's vulnerability to the development of tumors may depend from the characteristics of the NO generating systems. The content of NO in the tumor changed by ITU, inhibitor of iNOS, c-PTIO, traps and SNP, donor NO. Production of macrophage NO were evaluated by nitrites in the culture media. iNOS was assessed using the Western blot analysis. Phenotype of macrophages was assessed using cytometry for CD labels. Life span of mice C57BL/6N with Ehrlich tumor was 25% greater than that of the C57BL/6J. Reducing the content of NO in the tumor reduced life expectancy of high-resistance to tumor subline C57BL/6N at 23%. Increase of NO increased life expectancy of low-resistance subline C57BL/6J at 26%. Macrophages of C57BL/6N were 1.5 times higher contents of iNOS and NO production, as compared with macrophages of C57BL/6J. CD phenotype markers determined the macrophage phenotype C57BL/6N as M1 and C57BL/6J mice macrophage phenotype as M2. Thus, the body's vulnerability to the development of tumors may depend from the characteristics of the NO generating systems. C57BL/6J, unlike C57BL/6N does not synthesize NNT (nicotinamide nucleotide transhydrogenase) and have differences in the single nucleotide polymorphism (SNP). The important role of NO in the resistance to Carcinoma, NNT and SNP deserve attention in the development of new methods of antitumor therapy. PMID:26226691

  8. 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

  9. Investigation of the transient aerodynamic phenomena associated with passing manoeuvres

    Science.gov (United States)

    Noger, C.; Regardin, C.; Széchényi, E.

    2005-11-01

    Passing manoeuvres and crosswind can have significant effects on the stability of road vehicles. The transient aerodynamics, which interacts with suspension, steering geometry and driver reaction is not well understood. When two vehicles overtake or cross, they mutually influence the flow field around each other, and under certain conditions, can generate severe gust loads that act as additional forces on both vehicles. The transient forces acting on them are a function of the longitudinal and transverse spacings and of the relative velocity between the two vehicles. Wind tunnel experiments have been conducted in one of the automotive wind tunnels of the Institut Aérotechnique of Saint-Cyr l’École to simulate the transient overtaking process between two models of a simple generic automobile shape. The tests were designed to study the effects of various parameters such as the longitudinal and transverse spacing, the relative velocity and the crosswind on the aerodynamic forces and moments generated on the overtaken and overtaking vehicles. Test results characterize the transient aerodynamic side force as well as the yawing moment coefficients in terms of these parameters. Measurements of the drag force coefficient as well as the static pressure distribution around the overtaken vehicle complete the understanding. The main results indicate the aerodynamic coefficients of the overtaken vehicle to be velocity independent within the limit of the test parameters, while unsteady aerodynamic effects appear in the case of an overtaking vehicle. The mutual interference effects between the vehicles vary as a linear function of the transverse spacing and the crosswind does not really generate any new unsteady behaviour.

  10. A super-ductile alloy for the die-casting of aluminium automotive body structural components

    OpenAIRE

    Watson, D.; Ji, S; Fan, Z.

    2014-01-01

    Super-ductile die-cast aluminium alloys are critical to future light-weighting of automotive body structures. This paper introduces a die-cast aluminium alloy that can satisfy the requirements of these applications. After a review of currently available alloys, the requirement of a die-cast aluminium alloy for automotive body structural parts is proposed and an Al-Mg-Si system is suggested. The effect of the alloying elements, in the composition, has been investigated on the microstructure an...

  11. 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

  12. 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.

  13. Future Challenges and Opportunities in Aerodynamics

    Science.gov (United States)

    Kumar, Ajay; Hefner, Jerry N.

    2000-01-01

    Investments in aeronautics research and technology have declined substantially over the last decade, in part due to the perception that technologies required in aircraft design are fairly mature and readily available. This perception is being driven by the fact that aircraft configurations, particularly the transport aircraft, have evolved only incrementally, over last several decades. If however, one considers that the growth in air travel is expected to triple in the next 20 years, it becomes quickly obvious that the evolutionary development of technologies is not going to meet the increased demands for safety, environmental compatibility, capacity, and economic viability. Instead, breakthrough technologies will he required both in traditional disciplines of aerodynamics, propulsion, structures, materials, controls, and avionics as well as in the multidisciplinary integration of these technologies into the design of future aerospace vehicles concepts. The paper discusses challenges and opportunities in the field of aerodynamics over the next decade. Future technology advancements in aerodynamics will hinge on our ability, to understand, model, and control complex, three-dimensional, unsteady viscous flow across the speed range. This understanding is critical for developing innovative flow and noise control technologies and advanced design tools that will revolutionize future aerospace vehicle systems and concepts. Specifically, the paper focuses on advanced vehicle concepts, flow and noise control technologies, and advanced design and analysis tools.

  14. 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.

  15. The adenovirus E4 11 k protein binds and relocalizes the cytoplasmic P-body component Ddx6 to aggresomes

    International Nuclear Information System (INIS)

    The adenovirus E4 11 k protein, product of E4 ORF3, is required in infection for processes including normal accumulation of viral late mRNAs. 11 k restructures both the nucleus and cytoplasm of infected cells by relocalizing specific host cell target proteins, most strikingly components of nuclear PML oncogenic domains. It is likely that in many cases relocalization inactivates target proteins to produce 11 k's effects, although the mechanism and targets for stimulation of late mRNA accumulation is unknown. We have identified a new set of proteins relocalized by 11 k: at least five protein components of cytoplasmic mRNA processing bodies (p-bodies) are found in 11 k-induced cytoplasmic aggresomes, sites where proteins are inactivated or destroyed. One of these p-body proteins, RNA helicase Ddx6, binds 11 k, suggesting a mechanism for relocalization. Because p-bodies are sites for mRNA degradation, their modification by 11 k may provide an explanation for the role of 11 k in viral late mRNA accumulation.

  16. 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, ...... solution for the admittance of a turbulent flow past a flat plate [4] and two types of bridge girder sections. A fair agreement is observed for sufficiently low turbulence intensities and sufficient spatial and temporal resolutions.......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...

  17. 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.

  18. 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

  19. Demographic and clinical features of inclusion body myositis in North America

    Science.gov (United States)

    Paltiel, A. David; Ingvarsson, Einar; Lee, Donald K. K.; Leff, Richard L.; Nowak, Richard J.; Petschke, Kurt D.; Richards-Shubik, Seth; Zhou, Ange; Shubik, Martin; O’Connor, Kevin C.

    2016-01-01

    Objective Define the demographics, natural history, and clinical management of patients with inclusion body myositis (IBM). Background Few studies of the demographics, natural history, and clinical management of IBM have been performed in a large patient population. Methods A cross-sectional, self-reporting survey was conducted. Results The mean age of the 916 participants was 70.4 years, the male-to-female ratio was 2:1, and the majority reported difficulty with ambulation and activities of daily living. The earliest symptoms included impaired use and weakness of arms and legs. The mean time from first symptoms to diagnosis was 4.7 years. Half reported that IBM was their initial diagnosis. A composite functional index negatively associated with age, disease duration, and positively associated with participation in exercise. Conclusion These data are valuable for informing patients how IBM manifestations are expected to impair daily living and indicate that self-reporting could be used to establish outcome measures in clinical trials. PMID:25557419

  20. 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.

  1. 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.

  2. Handling and safety enhancement of race cars using active aerodynamic systems

    Science.gov (United States)

    Diba, Fereydoon; Barari, Ahmad; Esmailzadeh, Ebrahim

    2014-09-01

    A methodology is presented in this work that employs the active inverted wings to enhance the road holding by increasing the downward force on the tyres. In the proposed active system, the angles of attack of the vehicle's wings are adjusted by using a real-time controller to increase the road holding and hence improve the vehicle handling. The handling of the race car and safety of the driver are two important concerns in the design of race cars. The handling of a vehicle depends on the dynamic capabilities of the vehicle and also the pneumatic tyres' limitations. The vehicle side-slip angle, as a measure of the vehicle dynamic safety, should be narrowed into an acceptable range. This paper demonstrates that active inverted wings can provide noteworthy dynamic capabilities and enhance the safety features of race cars. Detailed analytical study and formulations of the race car nonlinear model with the airfoils are presented. Computer simulations are carried out to evaluate the performance of the proposed active aerodynamic system.

  3. 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

  4. 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.

  5. Steady-state dynamics of Cajal body components in the Xenopus germinal vesicle

    OpenAIRE

    Handwerger, Korie E.; Murphy, Christine; Gall, Joseph G.

    2003-01-01

    Cajal bodies (CBs) are evolutionarily conserved nuclear organelles that contain many factors involved in the transcription and processing of RNA. It has been suggested that macromolecular complexes preassemble or undergo maturation within CBs before they function elsewhere in the nucleus. Most such models of CB function predict a continuous flow of molecules between CBs and the nucleoplasm, but there are few data that directly support this view. We used fluorescence recovery after photobleach...

  6. 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....

  7. Clustering of immunological, metabolic and genetic features in latent autoimmune diabetes in adults: evidence from principal component analysis.

    Science.gov (United States)

    Pes, Giovanni Mario; Delitala, Alessandro Palmerio; Errigo, Alessandra; Delitala, Giuseppe; Dore, Maria Pina

    2016-06-01

    Latent autoimmune diabetes in adults (LADA) which accounts for more than 10 % of all cases of diabetes is characterized by onset after age 30, absence of ketoacidosis, insulin independence for at least 6 months, and presence of circulating islet-cell antibodies. Its marked heterogeneity in clinical features and immunological markers suggests the existence of multiple mechanisms underlying its pathogenesis. The principal component (PC) analysis is a statistical approach used for finding patterns in data of high dimension. In this study the PC analysis was applied to a set of variables from a cohort of Sardinian LADA patients to identify a smaller number of latent patterns. A list of 11 variables including clinical (gender, BMI, lipid profile, systolic and diastolic blood pressure and insulin-free time period), immunological (anti-GAD65, anti-IA-2 and anti-TPO antibody titers) and genetic features (predisposing gene variants previously identified as risk factors for autoimmune diabetes) retrieved from clinical records of 238 LADA patients referred to the Internal Medicine Unit of University of Sassari, Italy, were analyzed by PC analysis. The predictive value of each PC on the further development of insulin dependence was evaluated using Kaplan-Meier curves. Overall 4 clusters were identified by PC analysis. In component PC-1, the dominant variables were: BMI, triglycerides, systolic and diastolic blood pressure and duration of insulin-free time period; in PC-2: genetic variables such as Class II HLA, CTLA-4 as well as anti-GAD65, anti-IA-2 and anti-TPO antibody titers, and the insulin-free time period predominated; in PC-3: gender and triglycerides; and in PC-4: total cholesterol. These components explained 18, 15, 12, and 12 %, respectively, of the total variance in the LADA cohort. The predictive power of insulin dependence of the four components was different. PC-2 (characterized mostly by high antibody titers and presence of predisposing genetic markers

  8. 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

  9. 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.

  10. 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.

  11. 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;

    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...

  12. Hypersonic Inflatable Aerodynamic Decelerator (HIAD) Technology Development Overview

    Science.gov (United States)

    Hughes, Stephen J.; Cheatwood, F. McNeil; Calomino, Anthony M.; Wright, Henry S.

    2013-01-01

    Aerocover configuration. Both the Aerocovers and the TPS were populated with high contrast targets so that photogrammetric solutions of the loaded surface could be created. These solutions both refined the aerodynamic shape for CFD modeling and provided a deformed shape to validate structural Finite Element Analysis (FEA) models. Extensive aerothermal testing has been performed on the TPS candidates. This testing has been conducted in several facilities across the country. The majority of the testing has been conducted in the Boeing Large Core Arc Tunnel (LCAT). HIAD is continuing to mature testing methodology in this facility and is developing new test sample fixtures and control methodologies to improve understanding and quality of the environments to which the samples are subjected. Additional testing has been and continues to be performed in the NASA LaRC 8ft High Temperature Tunnel, where samples up to 2ft by 2ft are being tested over representative underlying structures incorporating construction features such as sewn seams and through-thickness quilting. With the successful completion to the IRVE-3 flight demonstration, mission planning efforts are ramping up on the development of the HIAD Earth Atmospheric Reenty Test (HEART) which will demonstrate a relevant scale vehicle in relevant environments via a large-scale aeroshell (approximately 8.5m) entering at orbital velocity (approximately 7km/sec) with an entry mass on the order of 4MT. Also, the Build to Print (BTP) hardware built as a risk mitigation for the IRVE-3 project to have a "spare" ready to go in the event of a launch vehicle delivery failure is now available for an additional sub-orbital flight experiment. Mission planning is underway to define a mission that can utilize this existing hardware and help the HIAD project further mature this technology.

  13. 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...

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

    Science.gov (United States)

    Lin, Shin-Yi; Chen, Yu-Kai; Yu, Hui-Tzu; Barseghyan, Gayane S; Asatiani, Mikheil D; Wasser, Solomon P; Mau, Jeng-Leun

    2013-01-01

    Mushrooms (including fruiting bodies and mycelia) contain several bioactive components such as lovastatin, γ-aminobutyric acid (GABA), and ergothioneine. This article reports the results of 49 samples, including 9 fruiting bodies, 39 mycelia, and 1 vegetative cell, of 35 species of culinary-medicinal mushrooms from 18 genera: Agaricus, Agrocybe, Coprinus, Cordyceps, Cyathus, Daedalia, Flammulina, Fomes, Ganoderma, Grifola, Laetiporus, Lentinus, Morchella, Ophiocordyceps, Pleurotus, Trametes, Tremella, and Verpa. The results show that Cyathus striatus strain 978 contained the highest amount of lovastatin (995.66 mg/kg) in mycelia. Among fruiting bodies, 6 samples contained a high amount of GABA (274.86-822.45 mg/kg), whereas among mycelia, contents of GABA in 27 samples ranged from 215.36 to 2811.85 mg/kg. Among mycelia, Pleurotus cornucopiae strain 1101 contained the highest amount of ergothioneine (3482.09 mg/kg). Overall, these 3 bioactive components were commonly found in most mushrooms, and the results obtained might be related to their beneficial effects. PMID:23662618

  15. 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.

  16. THE CONDITIONS OF PREDICTION OF THE PARAMETRIC COMPONENTS OF THE TERMINATION CONTROL SYSTEM OF THE UNMANNED AERIAL VEHICLE FLIGHT PATH

    Directory of Open Access Journals (Sweden)

    Yaroslav Kondrashov

    2011-03-01

    Full Text Available Abstract. According to the results of measurements on board of Unmanned Aerial Vehicle the distancevector D is formed in the inertial coordinate system, and in mathematical modeling - in the Greenwichsystem of coordinates. The velocity vector k V is formed by the navigation system in the trajectory coordinatesystem. Defined by this way the initial conditions gives the possibility to predict the terminal parameters offlight (descent of Unmanned Aerial Vehicle.Keywords: control system of the unmanned aerial vehicle flight path and landing, motion parameters,termination control.

  17. 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.

  18. 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.

  19. 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

  20. 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

  1. Possibility of inferring some general features and mineralogical composition of deep clay bodies by means of superficial observations

    International Nuclear Information System (INIS)

    The CNEN (Italian Nuclear Energy Commission) is highly engaged in the study of many physical features of the territory for sitological purposes. In this frame the deeply buried clay deposits represent an area of study of great interest. Direct informations on deep deposits are often lacking. The CNEN has therefore faced the problem of the possibility of superficial observations to be used in predicting some characters of underground clay bodies. Systematic investigations carried on pliocenic clays occurring in Italy have shown: 1) Pliocenic clay deposits show a clear regional distribution according well defined mineralogical provinces; 2) Mineralogy of clay deposits coarsely depends on lithological composition of ancient feeder basins. The obtained results may allow extrapolations to deep deposits

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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

  8. 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.)

  9. 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.

  10. 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. PMID:25479377

  11. 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)

  12. 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.

  13. On-board energy management for high-speed aerospace vehicles: System and component-level energy-based optimization and analysis

    Science.gov (United States)

    Taylor, Trent Matthew

    This dissertation addresses in detail three main topics for advancing the state-of-the-art in hypersonic aerospace systems: (1) the development of a synergistic method based on entropy generation in order to analyze, evaluate, and optimize vehicle performance, (2) the development and analysis of innovative unconventional flow-control methods for increasing vehicle performance utilizing entropy generation as a fundamental descriptor and predictor of performance, and (3) an investigation of issues arising when evaluating (predicting) actual flight vehicle performance using ground test facilities. Vehicle performance is analyzed beginning from fundamental considerations involving fluid and thermodynamic balance relationships. The results enable the use of entropy generation as the true "common currency" (single loss parameter) for systematic and consistent evaluation of performance losses across the vehicle as an integrated system. Innovative flow control methods are modeled using state of the art CFD codes in which the flow is energized in targeted local zones with emphasis on shock wave modification. Substantial drag reductions are observed such that drag can decrease to 25% of the baseline. Full vehicle studies are then conducted by comparing traditional and flow-controlled designs and very similar axial force is found with an accompanying increase in lift for the flow-control design to account for on-board energy-addition components. Finally, a full engine flowpath configuration is designed for computational studies of ground test performance versus actual flight performance with emphasis on understanding the effect of ground-based vitiate (test contaminant). It is observed that the presence of vitiate in the test medium can also have a significant first-order effect on ignition delay as well as the thermodynamic response to a given heat release in the fuel.

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. Discrete vortex method simulations of the aerodynamic admittance in bridge aerodynamics

    DEFF Research Database (Denmark)

    Rasmussen, Johannes Tophøj; Hejlesen, Mads Mølholm; Larsen, Allan; Walther, Jens Honore

    2010-01-01

    generated prior to the simulations and is based on analytic spectral densities of the atmospheric turbulence and a coherence function defining the spatial correlation of the flow. The method is validated by simulating the turbulent flow past a flat plate and past the Great Belt East bridge. The results are......We present a novel method for the simulation of the aerodynamic admittance in bluff body aerodynamics. The method introduces a model for describing oncoming turbulence in two-dimensional discrete vortex method simulations by seeding the upstream flow with vortex particles. The turbulence is...

  19. Airfoil Ice-Accretion Aerodynamics Simulation

    Science.gov (United States)

    Bragg, Michael B.; Broeren, Andy P.; Addy, Harold E.; Potapczuk, Mark G.; Guffond, Didier; Montreuil, E.

    2007-01-01

    NASA Glenn Research Center, ONERA, and the University of Illinois are conducting a major research program whose goal is to improve our understanding of the aerodynamic scaling of ice accretions on airfoils. The program when it is completed will result in validated scaled simulation methods that produce the essential aerodynamic features of the full-scale iced-airfoil. This research will provide some of the first, high-fidelity, full-scale, iced-airfoil aerodynamic data. An initial study classified ice accretions based on their aerodynamics into four types: roughness, streamwise ice, horn ice, and spanwise-ridge ice. Subscale testing using a NACA 23012 airfoil was performed in the NASA IRT and University of Illinois wind tunnel to better understand the aerodynamics of these ice types and to test various levels of ice simulation fidelity. These studies are briefly reviewed here and have been presented in more detail in other papers. Based on these results, full-scale testing at the ONERA F1 tunnel using cast ice shapes obtained from molds taken in the IRT will provide full-scale iced airfoil data from full-scale ice accretions. Using these data as a baseline, the final step is to validate the simulation methods in scale in the Illinois wind tunnel. Computational ice accretion methods including LEWICE and ONICE have been used to guide the experiments and are briefly described and results shown. When full-scale and simulation aerodynamic results are available, these data will be used to further develop computational tools. Thus the purpose of the paper is to present an overview of the program and key results to date.

  20. 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.

  1. 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

  2. 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....

  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. 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.

  5. 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.

  6. 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

  7. 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.

  8. Classification of Urban Feature from Unmanned Aerial Vehicle Images Using Gasvm Integration and Multi-Scale Segmentation

    Science.gov (United States)

    Modiri, M.; Salehabadi, A.; Mohebbi, M.; Hashemi, A. M.; Masumi, M.

    2015-12-01

    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.

  9. Space-time computational analysis of MAV flapping-wing aerodynamics with wing clapping

    Science.gov (United States)

    Takizawa, Kenji; Tezduyar, Tayfun E.; Buscher, Austin

    2015-06-01

    Computational analysis of flapping-wing aerodynamics with wing clapping was one of the classes of computations targeted in introducing the space-time (ST) interface-tracking method with topology change (ST-TC). The ST-TC method is a new version of the deforming-spatial-domain/stabilized ST (DSD/SST) method, enhanced with a master-slave system that maintains the connectivity of the "parent" fluid mechanics mesh when there is contact between the moving interfaces. With that enhancement and because of its ST nature, the ST-TC method can deal with an actual contact between solid surfaces in flow problems with moving interfaces. It accomplishes that while still possessing the desirable features of interface-tracking (moving-mesh) methods, such as better resolution of the boundary layers. Earlier versions of the DSD/SST method, with effective mesh update, were already able to handle moving-interface problems when the solid surfaces are in near contact or create near TC. Flapping-wing aerodynamics of an actual locust, with the forewings and hindwings crossing each other very close and creating near TC, is an example of successfully computed problems. Flapping-wing aerodynamics of a micro aerial vehicle (MAV) with the wings of an actual locust is another example. Here we show how the ST-TC method enables 3D computational analysis of flapping-wing aerodynamics of an MAV with wing clapping. In the analysis, the wings are brought into an actual contact when they clap. We present results for a model dragonfly MAV.

  10. 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.

  11. 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.

  12. 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.

  13. 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...

  14. 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, the...

  15. 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.

  16. Aerodynamic shape optimization using control theory

    Science.gov (United States)

    Reuther, James

    1996-01-01

    Aerodynamic shape design has long persisted as a difficult scientific challenge due its highly nonlinear flow physics and daunting geometric complexity. However, with the emergence of Computational Fluid Dynamics (CFD) it has become possible to make accurate predictions of flows which are not dominated by viscous effects. It is thus worthwhile to explore the extension of CFD methods for flow analysis to the treatment of aerodynamic shape design. Two new aerodynamic shape design methods are developed which combine existing CFD technology, optimal control theory, and numerical optimization techniques. Flow analysis methods for the potential flow equation and the Euler equations form the basis of the two respective design methods. In each case, optimal control theory is used to derive the adjoint differential equations, the solution of which provides the necessary gradient information to a numerical optimization method much more efficiently then by conventional finite differencing. Each technique uses a quasi-Newton numerical optimization algorithm to drive an aerodynamic objective function toward a minimum. An analytic grid perturbation method is developed to modify body fitted meshes to accommodate shape changes during the design process. Both Hicks-Henne perturbation functions and B-spline control points are explored as suitable design variables. The new methods prove to be computationally efficient and robust, and can be used for practical airfoil design including geometric and aerodynamic constraints. Objective functions are chosen to allow both inverse design to a target pressure distribution and wave drag minimization. Several design cases are presented for each method illustrating its practicality and efficiency. These include non-lifting and lifting airfoils operating at both subsonic and transonic conditions.

  17. Ceramic Matrix Composite (CMC) Thermal Protection Systems (TPS) and Hot Structures for Hypersonic Vehicles

    Science.gov (United States)

    Glass, David E.

    2008-01-01

    Thermal protection systems (TPS) and hot structures are required for a range of hypersonic vehicles ranging from ballistic reentry to hypersonic cruise vehicles, both within Earth's atmosphere and non-Earth atmospheres. The focus of this paper is on air breathing hypersonic vehicles in the Earth's atmosphere. This includes single-stage to orbit (SSTO), two-stage to orbit (TSTO) accelerators, access to space vehicles, and hypersonic cruise vehicles. This paper will start out with a brief discussion of aerodynamic heating and thermal management techniques to address the high heating, followed by an overview of TPS for rocket-launched and air-breathing vehicles. The argument is presented that as we move from rocket-based vehicles to air-breathing vehicles, we need to move away from the insulated airplane approach used on the Space Shuttle Orbiter to a wide range of TPS and hot structure approaches. The primary portion of the paper will discuss issues and design options for CMC TPS and hot structure components, including leading edges, acreage TPS, and control surfaces. The current state-of-the-art will be briefly discussed for some of the components. The two primary technical challenges impacting the use of CMC TPS and hot structures for hypersonic vehicles are environmental durability and fabrication, and will be discussed briefly.

  18. Application Program Interface for the Orion Aerodynamics Database

    Science.gov (United States)

    Robinson, Philip E.; Thompson, James

    2013-01-01

    The Application Programming Interface (API) for the Crew Exploration Vehicle (CEV) Aerodynamic Database has been developed to provide the developers of software an easily implemented, fully self-contained method of accessing the CEV Aerodynamic Database for use in their analysis and simulation tools. The API is programmed in C and provides a series of functions to interact with the database, such as initialization, selecting various options, and calculating the aerodynamic data. No special functions (file read/write, table lookup) are required on the host system other than those included with a standard ANSI C installation. It reads one or more files of aero data tables. Previous releases of aerodynamic databases for space vehicles have only included data tables and a document of the algorithm and equations to combine them for the total aerodynamic forces and moments. This process required each software tool to have a unique implementation of the database code. Errors or omissions in the documentation, or errors in the implementation, led to a lengthy and burdensome process of having to debug each instance of the code. Additionally, input file formats differ for each space vehicle simulation tool, requiring the aero database tables to be reformatted to meet the tool s input file structure requirements. Finally, the capabilities for built-in table lookup routines vary for each simulation tool. Implementation of a new database may require an update to and verification of the table lookup routines. This may be required if the number of dimensions of a data table exceeds the capability of the simulation tools built-in lookup routines. A single software solution was created to provide an aerodynamics software model that could be integrated into other simulation and analysis tools. The highly complex Orion aerodynamics model can then be quickly included in a wide variety of tools. The API code is written in ANSI C for ease of portability to a wide variety of systems. The

  19. 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

  20. 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.

  1. 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

  2. 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.

  3. 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...

  4. 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.

  5. 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.

  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. 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.

  8. 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.

  9. 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

  10. 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...

  11. 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.

  12. 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

  13. 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

  14. 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.

  15. Specialized computer architectures for computational aerodynamics

    Science.gov (United States)

    Stevenson, D. K.

    1978-01-01

    In recent years, computational fluid dynamics has made significant progress in modelling aerodynamic phenomena. Currently, one of the major barriers to future development lies in the compute-intensive nature of the numerical formulations and the relative high cost of performing these computations on commercially available general purpose computers, a cost high with respect to dollar expenditure and/or elapsed time. Today's computing technology will support a program designed to create specialized computing facilities to be dedicated to the important problems of computational aerodynamics. One of the still unresolved questions is the organization of the computing components in such a facility. The characteristics of fluid dynamic problems which will have significant impact on the choice of computer architecture for a specialized facility are reviewed.

  16. 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.

  17. Computational Study on the Aerodynamic Performance of Wind Turbine Airfoil Fitted with Coandă Jet

    OpenAIRE

    Djojodihardjo, H.; Abdul Hamid, M. F.; A. A. Jaafar; S. Basri; F. I. Romli; F. Mustapha; Rafie, A. S. Mohd; D. L. A. Abdul Majid

    2013-01-01

    Various methods of flow control for enhanced aerodynamic performance have been developed and applied to enhance and control the behavior of aerodynamic components. The use of Coandă effect for the enhancement of circulation and lift has gained renewed interest, in particular with the progress of CFD. The present work addresses the influence, effectiveness, and configuration of Coandă-jet fitted aerodynamic surface for improving lift and L/D, specifically for S809 airfoil, with a view on its i...

  18. 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.)

  19. 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.

  20. Effects of fluid behavior around low aspect ratio, low Reynolds number wings on aerodynamic stability

    Science.gov (United States)

    Shields, Matthew; Mohseni, Kamran

    2011-11-01

    The innovation of micro aerial vehicles (MAVs) has brought to attention the unique flow regime associated with low aspect ratio (LAR), low Reynolds number fliers. The dominant effects of developing tip vortices and leading edge vortices create a fundamentally different flow regime than that of conventional aircraft. An improved knowledge of low aspect ratio, low Reynolds number aerodynamics can be greatly beneficial for future MAV design. A little investigated but vital aspect of LAR aerodynamics is the behavior of the fluid as the wing yaws. Flow visualization experiments undertaken in the group for the canonical case of varying AR flat plates indicate that the propagation of the tip vortex keeps the flow attached over the upstream portion of the wing, while the downstream vortex is convected away from the wing. This induces asymmetric, destabilizing loading on the wing which has been observed to adversely affect MAV flight. In addition, experimental load measurements indicate significant nonlinearities in forces and moments which can be attributed to the development and propagation of these vortical structures. A non-dimensional analysis of the rigid body equations of motion indicates that these nonlinearities create dependencies which dramatically change the conventional linearization process. These flow phenomena are investigated with intent to apply to future MAV design.

  1. Fuel-Saving Potentials of Platooning Evaluated through Sparse Heavy-Duty Vehicle Position Data

    OpenAIRE

    Liang, Kuo-Yun; Mårtensson, Jonas; Johansson, Karl H.

    2014-01-01

    Vehicle platooning is important for heavy-duty vehicle manufacturers, due to the reduced aerodynamic drag for the follower vehicles, which gives an overall lower fuel consumption. Heavy-duty vehicle drivers are aware this fact and sometimes drive close to other heavy-duty vehicles. However, it is not currently well known how many vehicles are actually driving in such spontaneous platoons today. This paper studies the platooning rate of 1,800 heavy-duty vehicles by analyzing sparse vehicle pos...

  2. 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.

  3. 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.

  4. 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.

  5. Energy Efficiency in Heavy Vehicle Tires, Drivetrains, and Braking Systems; FINAL

    International Nuclear Information System (INIS)

    This document was prepared to support the primary goals of the Department of Energy, Office of Heavy Vehicle Technologies. These were recently stated as follows: ''Develop by 2004 the enabling technologies for a class 7-8 truck with a fuel efficiency of 10 mpg (at 65 mph) which will meet prevailing emission standards. For Class 3-6 trucks operating on an urban driving cycle, develop by 2004 commercially viable vehicles that achieve at least double the fuel economy of comparable current vehicles (1999), and as a research goal, reduce criteria pollutants to 30% below EPA standards. Develop by 2004 the diesel engine enabling technologies to support large-scale industry dieselization of Class 1 and 2 trucks, achieving a 35% fuel efficiency improvement over comparable gasoline-fueled trucks, while meeting applicable emissions standards.'' The enabling technologies for improving the fuel efficiency of trucks, include not only engine technologies but also technologies involved with lowering the rolling resistance of tires, reducing vehicle aerodynamic drag, improving thermal management, and reducing parasitic frictional losses in drive train components. Opportunities also exist for making better use of the energy that might ordinarily be dissipated during vehicle braking. Braking systems must be included in this evaluation since safety in truck operations is vital, and braking requirements are greater for vehicles having lowered resistance to rolling. The Office of Heavy Vehicle Technologies has initiated a program to improve the aerodynamics of heavy vehicles through wind tunnel testing, computational modeling, and on-road evaluations. That activity is described in a separate multi-year plan; therefore, emphasis in this document will be on tires, drive trains, and braking systems. Recent, dramatic fluctuations in diesel fuel prices have emphasized the importance of effecting savings in truck fuel economy by implementing new component designs and materials

  6. 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.

  7. Sharp-B01: An Important Element of NASA's Launch Vehicle Development Program

    Science.gov (United States)

    Rasky, Daniel J.

    1998-01-01

    Sharp body designs for future reusable launch vehicles offer a number of attractive features including allowing zero staging, enabling airbreathing and lofting ascents, and potentially providing global cross range re-entries with continuous communications. The Slender Hypersonic Aerothermodynamic Research Program (SHARP) was initiated by NASA Ames to demonstrate sharp, passive leading edge designs for hypersonic vehicles, incorporating new ultra-high temperature ceramics. This paper will discuss how SHARP will provide an important technology base for making sharp body hypersonic vehicle designs a reality, and how this activity fits into NASA's overall program for developing next generation reusable launch vehicles.

  8. Shaping up blunt bodies

    OpenAIRE

    Muller, M

    2007-01-01

    Lorries are great for transporting goods, but their inferior aerodynamics means they get fewer kilometers a liter of fuel. Bad news indeed for the environment, and for hauliers purses. But according to researchers at Delft University of Technology, cones and wings attached to the rear end along with technical tricks suspended under the vehicle could reduce fuel consumption by up to fifteen percent.

  9. 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

  10. 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.

  11. 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

  12. Flap effectiveness appraisal for winged re-entry vehicles

    Science.gov (United States)

    de Rosa, Donato; Pezzella, Giuseppe; Donelli, Raffaele S.; Viviani, Antonio

    2016-05-01

    The interactions between shock waves and boundary layer are commonplace in hypersonic aerodynamics. They represent a very challenging design issue for hypersonic vehicle. A typical example of shock wave boundary layer interaction is the flowfield past aerodynamic surfaces during control. As a consequence, such flow interaction phenomena influence both vehicle aerodynamics and aerothermodynamics. In this framework, the present research effort describes the numerical activity performed to simulate the flowfield past a deflected flap in hypersonic flowfield conditions for a winged re-entry vehicle.

  13. 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.

  14. 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.

  15. Optimal trajectory and heat load analysis of different shape lifting reentry vehicles for medium range application

    Directory of Open Access Journals (Sweden)

    S. Tauqeer ul Islam Rizvi

    2015-12-01

    Full Text Available The objective of the paper is to compute the optimal burn-out conditions and control requirements that would result in maximum down-range/cross-range performance of a waverider type hypersonic boost-glide (HBG vehicle within the medium and intermediate ranges, and compare its performance with the performances of wing-body and lifting-body vehicles vis-à-vis the g-load and the integrated heat load experienced by vehicles for the medium-sized launch vehicle under study. Trajectory optimization studies were carried out by considering the heat rate and dynamic pressure constraints. The trajectory optimization problem is modeled as a nonlinear, multiphase, constraint optimal control problem and is solved using a hp-adaptive pseudospectral method. Detail modeling aspects of mass, aerodynamics and aerothermodynamics for the launch and glide vehicles have been discussed. It was found that the optimal burn-out angles for waverider and wing-body configurations are approximately 5° and 14.8°, respectively, for maximum down-range performance under the constraint heat rate environment. The down-range and cross-range performance of HBG waverider configuration is nearly 1.3 and 2 times that of wing-body configuration respectively. The integrated heat load experienced by the HBG waverider was found to be approximately an order of magnitude higher than that of a lifting-body configuration and 5 times that of a wing-body configuration. The footprints and corresponding heat loads and control requirements for the three types of glide vehicles are discussed for the medium range launch vehicle under consideration.

  16. 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.

  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 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...... Wind 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 the...

  18. 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....

  19. Wind turbine wake aerodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Vermeer, L.J. [Delft University of Technology (Netherlands). Section Wind Energy; Sorensen, J.N. [Technical University of Denmark, Lyngby (Denmark). Dept. of Mechanical Engineering; Crespo, A. [Universidad Politecnica de Madrid (Spain). Dpto. de Ingenieria Energetica y Fluidomecanica

    2003-10-01

    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 focuses 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. (author)

  20. Cable Aerodynamic Control

    DEFF Research Database (Denmark)

    Kleissl, Kenneth

    categorization of the different control technics together with an identification of two key mechanisms for reduction of the design drag force. During this project extensive experimental work examining the aerodynamics of the currently used cable surface modifications together with new innovative proposals have...... drag force due to the high intensity of streamwise vorticity, whereas the helical fillets resulted in a more gradual flow transition because of the spanwise variation. During yawed flow conditions, the asymmetrical appearance of the helical solution was found to induce a significant lift force with a...... were tested. While a proper discrete helical arrangement of Cylindrical Vortex Generators resulted in a superior drag performance, only systems applying "mini-strakes" were capable of complete rivulet suppression. When the strakes was positioned in a staggered helical arrangement, the innovative system...