Sample records for air cushion vehicle

  1. Air cushion vehicle response to waves in the surf zone

    Microsoft Academic Search

    Manhar Dhanak

    2009-01-01

    Heave motion of an air-cushion vehicle in response to wave encounters as it transitions through the surf zone is presented. Wave transformation from deep waters to the beach is described using the model of Dally et al. (1985) and the shallow-water SWAN model. The vehicle considered is a surface effect ship (SES) that maintains an air cushion between its two

  2. Air cushion vehicles for arctic operation

    NASA Astrophysics Data System (ADS)

    Koleser, J.; Lavis, D. R.

    1986-09-01

    Attention is given to the results of the NAVSEA FY85 Surface Ship Concept Formulation Design Study for an initial operational capability year-2000 air cushion vehicle (ACV) suitable for logistics and general search/rescue duties in the Arctic. Two designs were developed during the study; the first utilized an ACV design synthesis math model while the second evolved as a derivative of an existing U.S. production craft. Both are regarded as feasible from an engineering and naval architectural standpoint. Results of performance and cost trade-off studies suggest that, for an Arctic ACV, gas turbines are the preferred power plant choice and an aluminum alloy is the preferred hull structural material choice. The most appropriate skirt height is approximately 12 ft.

  3. Tracked Air Cushion Vehicle Suspension Models: Analysis and Comparison

    Microsoft Academic Search

    DEVENDRA P. GARG; BULENT E. PLATIN

    1973-01-01

    In this paper several dynamical models of fluid suspensions for tracked air cushion vehicles are analyzed and compared. Specifically, the models considered conform to: a fifth-order linear suspension, a nonlinear configuration with a constant supply pressure, a nonlinear model with compressor characteristics, and a sixth-order nonlinear model with a supply duct connecting the compressor to the cushion chamber. Nonlinearities included

  4. Creating new cities through the large air-cushion vehicle.

    NASA Technical Reports Server (NTRS)

    Anderson, J. L.; Finnegan, P. M.

    1972-01-01

    The air-cushion vehicle (ACV) can travel over concrete roads, grass, sand, mud, swamp, snow, ice, and water. This mobility makes possible a totally new geographical freedom in choosing transportation routes, locating ports, and laying out a city. By the 1980s fleets of large ACV freighters could begin carrying ocean-going cargo. The mobility of an ACV fleet would allow placing hoverports away from areas now crowded. New cities could rise along shallow or reef-bound seacoasts and rivers, just as cities once rose around deep-water seaports.

  5. MathCAD model for the estimation of cost and main characteristics of air-cushion vehicles in the preliminary design stage

    E-print Network

    Gougoulidis, Georgios

    2005-01-01

    In the naval architecture terminology, the term ACV (Air Cushion Vehicle) refers to this category of vehicles, in which a significant portion of the weight (or all the weight) is supported by forces arising from air pressures ...

  6. Air-cushion tankers for Alaskan North Slope oil

    NASA Technical Reports Server (NTRS)

    Anderson, J. L.

    1973-01-01

    A concept is described for transporting oil from the Arctic to southern markets in 10,000-ton, chemically fueled air-cushion vehicles (ACV's) configured as tankers. Based on preliminary cost estimates the conceptual ACV tanker system as tailored to the transportation of Alaskan North Slope oil could deliver the oil for about the same price per barrel as the proposed trans-Alaska pipeline with only one-third of the capital investment. The report includes the description of the conceptual system and its operation; preliminary cost estimates; an appraisal of ACV tanker development; and a comparison of system costs, versatility, vulnerability, and ecological effect with those of the trans-Alaska pipeline.

  7. Experimental and analytical studies of advanced air cushion landing systems

    NASA Technical Reports Server (NTRS)

    Lee, E. G. S.; Boghani, A. B.; Captain, K. M.; Rutishauser, H. J.; Farley, H. L.; Fish, R. B.; Jeffcoat, R. L.

    1981-01-01

    Several concepts are developed for air cushion landing systems (ACLS) which have the potential for improving performance characteristics (roll stiffness, heave damping, and trunk flutter), and reducing fabrication cost and complexity. After an initial screening, the following five concepts were evaluated in detail: damped trunk, filled trunk, compartmented trunk, segmented trunk, and roll feedback control. The evaluation was based on tests performed on scale models. An ACLS dynamic simulation developed earlier is updated so that it can be used to predict the performance of full-scale ACLS incorporating these refinements. The simulation was validated through scale-model tests. A full-scale ACLS based on the segmented trunk concept was fabricated and installed on the NASA ACLS test vehicle, where it is used to support advanced system development. A geometrically-scaled model (one third full scale) of the NASA test vehicle was fabricated and tested. This model, evaluated by means of a series of static and dynamic tests, is used to investigate scaling relationships between reduced and full-scale models. The analytical model developed earlier is applied to simulate both the one third scale and the full scale response.

  8. Duct effects on the heave stability of plenum air cushions

    Microsoft Academic Search

    M. J. Hinchey; P. A. Sullivan

    1978-01-01

    Linear heave stability boundaries for a fun-duct-plenum air cushion suspension system are presented. These were obtained by using a quasi-static pressure-flow relationship for the fan, a finite element discretization for one dimensional unsteady duct flow, and a lumped capacitance model for the plenum. They indicate that even relatively short ducts can have a major effect at practical flow rates on

  9. Compressible air cushioning in liquid-solid impacts Peter D. Hicks

    E-print Network

    Purvis, Richard

    Compressible air cushioning in liquid-solid impacts Peter D. Hicks Department of Mechanical of Mathematics, University of East Anglia, Norwich, NR4 7TJ, UK. r.purvis@uea.ac.uk Abstract--Air cushioning the influence of air compressibility. Building on earlier incompress- ible analyses, a local asymptotic model

  10. An alternating pressure sequence proposal for an air-cell cushion for preventing pressure ulcers.

    PubMed

    Arias, Sandra; Cardiel, Eladio; Rogeli, Pablo; Mori, Taketoshi; Nakagami, Gojiro; Noguchi, Hiroshi; Sanada, Hiromi

    2014-01-01

    The distribution and release of pressure on ischial regions are two important parameters for evaluating the effectiveness of a cushion; especially the release of pressure over time on ischial tuberosities, which is significant for preventing pressure ulcers. The aim of this work is to evaluate the effect on interface pressure through the application of a proposed alternating pressure sequence for an air-cell cushion. Six healthy volunteers were asked to sit on the air cell cushion, in static and alternating modes, as well as on a typical foam cushion for 12 minutes. Interface pressure was monitored with a matrix sensor system. Interface pressure values on ischial tuberosities, user contact area and pressure distribution were analyzed. Results showed that IP on IT tends to increase in both foam and static cushions, while in alternating cushion IP on IT tends to decrease. User contact area was significantly larger in alternating cushion than in static or foam cushions. Moreover, there is a better pressure re-distribution with alternating cushion than with the other cushions. The goal of the alternating sequence is to redistribute pressure and stimulate the ischial regions in order to promote blood flow and prevent pressure occurring in wheelchair users. PMID:25570740

  11. Reduced energy and volume air pump for a seat cushion

    DOEpatents

    Vaughn, Mark R. (Albuquerque, NM); Constantineau, Edward J. (Albuquerque, NM); Groves, Gordon E. (Tijeras, NM)

    1997-01-01

    An efficient pump system for transferring air between sets of bladders in a cushion. The pump system utilizes a reversible piston within a cylinder in conjunction with an equalizing valve in the piston which opens when the piston reaches the end of travel in one direction. The weight of a seated user then forces air back across the piston from an inflated bladder to the previously deflated bladder until the pressure is equalized. In this fashion the work done by the pump is cut in half. The inflation and deflation of the different bladders is controlled to vary the pressure on the several pressure points of a seated user. A principal application is for wheel chair use to prevent pressure ulcers.

  12. Reduced energy and volume air pump for a seat cushion

    DOEpatents

    Vaughn, M.R.; Constantineau, E.J.; Groves, G.E.

    1997-08-19

    An efficient pump system is described for transferring air between sets of bladders in a cushion. The pump system utilizes a reversible piston within a cylinder in conjunction with an equalizing valve in the piston which opens when the piston reaches the end of travel in one direction. The weight of a seated user then forces air back across the piston from an inflated bladder to the previously deflated bladder until the pressure is equalized. In this fashion the work done by the pump is cut in half. The inflation and deflation of the different bladders is controlled to vary the pressure on the several pressure points of a seated user. A principal application is for wheel chair use to prevent pressure ulcers. 12 figs.

  13. Highway Crash Cushions

    E-print Network

    White, Monroe Carlton

    1971-01-01

    roadside structures. A device which would cushion vehicles that collide with these rigid obstacles could thus save the lives of and decrease injuries to occupants, and minimize property damage to colliding vehicles. Four such devices are presently... (CONTINUED) ~Cha ter ~Pa e Idealization of vehicle and cushion The vehicle The cushion Comparison of simulations and crash test data 100 100 101 105 In-Service Performance 108 Introduction Collisions and injuries at sites Three unique collisions...

  14. Highway Crash Cushions 

    E-print Network

    White, Monroe Carlton

    1971-01-01

    Applied to Monomodular Cushion used in Test 1146-3 33 Comparison of Theoretical and Experimental Values for Monomodular Cushion used in Test 1146-3 34 10 Summary of Modular Crash Cushion Head-on Crash Tests 36 Summary of Modular Crash Cushion Side... 21 Monomodular Design Graph and Nomograph to Determine nr and ND ~ ~ ~ ~ . ~ ~ ~ 22 Vehicle Before and After Collision, Test 505-1E . . 39 Cushion Before and After Collision, Test 505-1E . . 40 10 12 Sequential Photographs of Test 1146...

  15. Air vehicle path planning

    NASA Astrophysics Data System (ADS)

    Hebert, Jeffrey Michael

    This dissertation explores optimal path planning for air vehicles. An air vehicle exposed to illumination by a tracking radar is considered and the problem of determining an optimal planar trajectory connecting two prespecified points is addressed. An analytic solution yielding the trajectory minimizing the received radar energy reflected from the target is derived using the Calculus of Variations. Additionally, the related problem of an air vehicle tracked by a passive sensor is also solved. Using the insights gained from the single air vehicle radar exposure minimization problem, a hierarchical cooperative control law is formulated to determine the optimal trajectories that minimize the cumulative exposure of multiple air vehicles during a rendezvous maneuver. The problem of one air vehicle minimizing exposure to multiple radars is also addressed using a variational approach, as well as a sub-optimal minmax argument. Local and global optimality issues are explored. A novel decision criterion is developed determining the geometric conditions dictating when it is preferable to go between or around two radars. Lastly, an optimal minimum time control law is obtained for the target identification and classification mission of an autonomous air vehicle. This work demonstrates that an awareness of the consequences of embracing sub-optimal and non-globally optimal solutions for optimization problems, such as air vehicle path planning, is essential.

  16. Air vehicle path planning

    Microsoft Academic Search

    Jeffrey Michael Hebert

    2001-01-01

    This dissertation explores optimal path planning for air vehicles. An air vehicle exposed to illumination by a tracking radar is considered and the problem of determining an optimal planar trajectory connecting two prespecified points is addressed. An analytic solution yielding the trajectory minimizing the received radar energy reflected from the target is derived using the Calculus of Variations. Additionally, the

  17. An analysis of contact stiffness between a finger and an object when wearing an air-cushioned glove: the effects of the air pressure.

    PubMed

    Wu, John Z; Wimer, Bryan M; Welcome, Daniel E; Dong, Ren G

    2012-04-01

    Air-cushioned gloves have the advantages of lighter weight, lower cost, and unique mechanical performance, compared to gloves made of conventional engineering materials. The goal of this study is to analyze the contact interaction between fingers and object when wearing an air-cushioned glove. The contact interactions between the the fingertip and air bubbles, which is considered as a cell of a typical air-cushioned glove, has been analyzed theoretically. Two-dimensional finite element models were developed for the analysis. The fingertip model was assumed to be composed of skin layers, subcutaneous tissue, bone, and nail. The air bubbles were modeled as air sealed in the container of nonelastic membrane. We simulated two common scenarios: a fingertip in contact with one single air bubble and with two air cushion bubbles simultaneously. Our simulation results indicated that the internal air pressure can modulate the fingertip-object contact characteristics. The contact stiffness reaches a minimum when the initial air pressure is equal to 1.3 and 1.05 times of the atmosphere pressure for the single air bubble and the double air bubble contact, respectively. Furthermore, the simulation results indicate that the double air bubble contact will result in smaller volumetric tissue strain than the single air bubble contact for the same force. PMID:21890395

  18. Modeling, simulation & optimization of the landing craft air cushion fleet readiness.

    SciTech Connect

    Engi, Dennis

    2006-10-01

    The Landing Craft Air Cushion is a high-speed, over-the-beach, fully amphibious landing craft capable of carrying a 60-75 ton payload. The LCAC fleet can serve to transport weapons systems, equipment, cargo and personnel from ship to shore and across the beach. This transport system is an integral part of our military arsenal and, as such, its readiness is an important consideration for our national security. Further, the best way to expend financial resources that have been allocated to maintain this fleet is a critical Issue. There is a clear coupling between the measure of Fleet Readiness as defined by the customer for this project and the information that is provided by Sandia's ProOpta methodology. Further, there is a richness in the data that provides even more value to the analyst. This report provides an analytic framework for understanding the connection between Fleet Readiness and the output provided by Sandia's ProOpta software. Further, this report highlights valuable information that can also be made available using the ProOpta output and concepts from basic probability theory. Finally, enabling assumptions along with areas that warrant consideration for further study are identified.

  19. A comparison of sitting pressures on wheelchair cushions as measured by air cell transducers and miniature electronic transducers.

    PubMed

    Palmieri, V R; Haelen, G T; Cochran, G V

    1980-01-01

    With increasing attention to cushion selection for patients subject to decubitus ulcers, greater efforts are being made to prescribe cushions based on individual need. Pressure measurements during sitting frequently are utilized as a clinical guide to the process of selection and fitting. To determine the relationship between pressure values recorded from different types of transducers, simultaneous measurements were made beneath the ischial tuberosities using a Scimedics air cell transducer on one side and a matrix of 5 Kulite electronic transducers on the other side of a subject while sitting on a series of 21 commercially available wheelchair cushions. Although these transducers are different in structure and function, statistically similar results were obtained. The air cell type of transducer appear to be more appropriate for routine clinical use, but caution is advised regarding interpretation of results in terms of absolute pressures due to the many variables involved -- these techniques are suitable primarily for comparative measurements to obtain the optimal seating support for a given patient. PMID:7236945

  20. Vehicle air suspension

    SciTech Connect

    Myers, P.F.; Strickler, R.A.; Warmuth, I.J. II

    1987-01-13

    A vehicle air suspension member is described comprising: (a) a hydraulic shock absorber with an axis of extension having an outer body containing an oil filled reservoir, a rod operatively positioned within the reservoir for coaxial reciprocal movement along the axis of extension, the rod extending axially outward from the outer body of the shock absorber; (b) an airspring having an upper retainer with a bore therethrough for receiving therein the rod, the upper retainer being connected to the rod by a resilient mounting means. An airspring piston is axially spaced apart from the upper retainer. A flexible, tubular member is sealingly connected at a first end thereof to the airspring piston and at a second end to the upper retainer to form a sealed pneumatic working cavity. A means is included for changing pressure within the working cavity, a port connecting the working chamber to the means for changing pressure. The airspring piston is attached to the outer body of the hydraulic shock absorber by a means for pivoting the shock absorber relative to the airspring piston during operation of the air suspension.

  1. Landing impact studies of a 0.3-scale model air cushion landing system for a Navy fighter airplane

    NASA Technical Reports Server (NTRS)

    Leland, T. J. W.; Thompson, W. C.

    1975-01-01

    An experimental study was conducted in order to determine the landing-impact behavior of a 0.3-scale, dynamically (but not physically) similar model of a high-density Navy fighter equipped with an air cushion landing system. The model was tested over a range of landing contact attitudes at high forward speeds and sink rates on a specialized test fixture at the Langley aircraft landing loads and traction facility. The investigation indicated that vertical acceleration at landing impact was highly dependent on the pitch angle at ground contact, the higher acceleration of approximately 5g occurring near zero body-pitch attitude. A limited number of low-speed taxi tests were made in order to determine model stability characteristics. The model was found to have good pitch-damping characteristics but stability in roll was marginal.

  2. Experimental and analytical dynamic flow characteristics of an axial-flow fan from an air cushion landing system model

    NASA Technical Reports Server (NTRS)

    Thompson, W. C.; Boghani, A. B.; Leland, T. J. W.

    1977-01-01

    An investigation was conducted to compare the steady-state and dynamic flow characteristics of an axial-flow fan which had been used previously as the air supply fan for some model air cushion landing system studies. Steady-state flow characteristics were determined in the standard manner by using differential orifice pressures for the flow regime from free flow to zero flow. In this same regime, a correlative technique was established so that fan inlet and outlet pressures could be used to measure dynamic flow as created by a rotating damper. Dynamic tests at damper frequencies up to 5 Hz showed very different flow characteristics when compared with steady-state flow, particularly with respect to peak pressures and the pressure-flow relationship at fan stall and unstall. A generalized, rational mathematical fan model was developed based on physical fan parameters and a steady-state flow characteristic. The model showed good correlation with experimental tests at damper frequencies up to 5 Hz.

  3. Compressed air propulsion system for a vehicle

    Microsoft Academic Search

    Johnson

    1986-01-01

    A compressed air propulsion system for a vehicle is described which consists of: an engine including cylinders reciprocatingly receiving therein a respective plurality of pistons, and an exhaust means connected to the cylinders, the engine drivingly connected to an axle of the vehicle to propel the vehicle; a transaxle operatively mounted on and rotatably driven by the vehicle; air compressing

  4. Oldenburg and Pan CO2 as Cushion Gas for CAES 1

    E-print Network

    Eisen, Michael

    Oldenburg and Pan CO2 as Cushion Gas for CAES 1 CO2 as Cushion Gas for Compressed Air Energy Compressed Air Oldenburg, C.M., Energy&Fuels, 17(1), 240­246, 2003. #12;Oldenburg and Pan CO2 as Cushion Gas as Cushion Gas for CAES 3 Renewables Need Energy Storage Source: Samir Succar, IAC Workshop, October 2005

  5. A New Aerodynamic Traction Principle for Handling Products on an Air Cushion

    E-print Network

    Paris-Sud XI, Université de

    and the lifting force depends on material properties. Pneumatic levitation approaches use air flow to apply. Aerodynamic levitation uses a flow of gas to apply a lift force. Two different approaches can be considered-effector of the manipulator which consists in a cup-shaped air nozzle [17]. Bernoulli levitation has been use in practical

  6. Foam Cushioning

    NASA Technical Reports Server (NTRS)

    1988-01-01

    One innovation developed by a contractor at Ames Research Center was an open cell polymeric foam material with unusual properties. Intended as padding for aircraft seats the material offered better impact protection against accidents, and also enhanced passenger comfort because it distributed body weight evenly over the entire contact area. Called a slow springback foam, it flows to match the contour of the body pressing against it, and returns to its original shape once the pressure is removed. It has many applications including aircraft cushions and padding, dental stools, and athletic equipment. Now it's used by Dynamic Systems, Inc. for medical applications such as wheel chairs for severely disabled people which allow them to sit for 3-8 hours where they used to be uncomfortable in 15-30 minutes.

  7. Unmanned air vehicles: new challenges in design

    Microsoft Academic Search

    T. J. Cord; S. Newbern

    2001-01-01

    The last ten years have seen a gradual shift in emphasis on future aeronautical technologies towards autonomous operation. This is most evident in the extended planning and development of unmanned air vehicles (UAV). UAV have grown from being target drones to unmanned combat air vehicles that will perform the suppression of enemy air defenses mission. Following generations may even include

  8. Aeroelastic Fixed Wing Micro Air Vehicle

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Wind tunnel testing of the University of Florida Aeroelastic Fixed Wing Micro Air Vehicle, biologically inspired flight systems. Photographed in building 1214, Basic Aerodynamics Research Tunnel (BART).

  9. Morphing Air Vehicle Concepts Serkan zgen*

    E-print Network

    Yaman, Yavuz

    Morphing Air Vehicle Concepts Serkan Özgen* , Yavuz Yaman, Melin ahin, Güçlü Seber, Levent Ünlüsoy, Turkey Abstract-This article summarizes the current level and trends in the emerging Morphing Air Vehicle of view. Part I introduces the morphing concept and its potential. Part II summarizes the present

  10. Travel Behavior and Older Vehicles: Implications for Air Quality and

    E-print Network

    Bertini, Robert L.

    Travel Behavior and Older Vehicles: Implications for Air Quality and Voluntary Accelerated Vehicle _____________________________________________________________ Date University of California, Berkeley Fall 2001 #12;Travel Behavior and Older Vehicles: Implications #12;Abstract Travel Behavior and Older Vehicles: Implications for Air Quality and Voluntary

  11. The design of hybrid cushion cars

    Microsoft Academic Search

    David Foster

    1972-01-01

    The new American car safety legislation, Standard 208, is “performance?based” in specifying a car crash speed up to which the occupants will not be injured but no indication is given how to do it. The two leading contenders for the actualization are the inflatable air?bag and The Hybrid Cushion Car invented by the author.The principle of the Hybrid Cushion Car

  12. Cooperative Control for Autonomous Air Vehicles

    Microsoft Academic Search

    Kevin Passino; Marios Polycarpou; David Jacques; Meir Pachter; Yang Liu; Yanli Yang; Matt Flint; Michael Baum

    The main objective of this research is to develop and evaluate the performance of strategies for cooperative control of autonomous\\u000a air vehicles that seek to gather information about a dynamic target environment, evade threats, and coordinate strikes against\\u000a targets. The air vehicles are equipped with sensors to view a limited region of the environment they are visiting, and are\\u000a able

  13. OPTIMAL DESIGN OF HIGHWAY CRASH CUSHIONS 

    E-print Network

    Zeng, Hao

    2011-04-29

    .......................................................................................................... 12 9 Vehicle deceleration vs. 50ms and vehicle deceleration vs. 10ms ....................... 12 10 Vehicle front crush and barrel deformation vs. time ............................................ 13 11 Optimization window of React 350... of a crash cushion begins with a crush curve for the barrels. This is an experimentally established relationship between force applied to the barrel and the reduction in its diameter (the “crush”). Data to generate a crush curve can be obtained...

  14. Aerodynamics for Revolutionary Air Vehicles

    NASA Technical Reports Server (NTRS)

    Sellers, William L., III; Singer, Bart A.; Leavitt, Laurence D.

    2003-01-01

    Aeronautics research has seriously declined partly because of the perception that it is a mature science and only incremental improvements are possible. Recent aeronautics roadmapping activities at NASA Langley paint a different picture of the future. Breakthroughs are still felt to be possible if we expand the current design space of today's vehicles and optimize the airspace and vehicles as a system. The paper describes some of the challenges that the aircraft and airline industry face. These challenges include political, technical and environmental issues. Examples of the opportunities and technologies that could provide a different vision for the future are discussed.

  15. Flexible-Wing-Based Micro Air Vehicles

    NASA Technical Reports Server (NTRS)

    Ifju, Peter G.; Jenkins, David A.; Ettinger, Scott; Lian, Yong-Sheng; Shyy, Wei; Waszak, Martin R.

    2002-01-01

    This paper documents the development and evaluation of an original flexible-wing-based Micro Air Vehicle (MAV) technology that reduces adverse effects of gusty wind conditions and unsteady aerodynamics, exhibits desirable flight stability, and enhances structural durability. The flexible wing concept has been demonstrated on aircraft with wingspans ranging from 18 inches to 5 inches. Salient features of the flexible-wing-based MAV, including the vehicle concept, flexible wing design, novel fabrication methods, aerodynamic assessment, and flight data analysis are presented.

  16. Development of an optimal impact energy absorber for highway crash cushions 

    E-print Network

    Michalec, Christopher Ryan

    2005-11-01

    The objective of this research is to develop a new and efficient method of absorbing a vehicle??s kinetic energy for highway safety crash cushions. A vehicle that makes a direct impact with a rigid highway structure traveling ...

  17. Energy harvesting from small unmmaned air vehicles

    Microsoft Academic Search

    S. R. Anton; A. Erturk; D. J. Inman

    2008-01-01

    Small, unmanned air vehicles (UAV) are used for reconnaissance by the military. Many of these are all electric with batteries as the primary source of energy. This talk explores the idea of extending the battery life (or flight time) of an electric radio controlled plane by using several harvesting concepts combined into one aircraft. Piezoceramic based harvesting using fiber based

  18. Vehicle overturning vulnerability from air blast loads

    NASA Astrophysics Data System (ADS)

    Robinson, R. R.; Napadensky, H.; Longinow, A.

    1984-08-01

    The overturning response of an armored personnel carrier to air blast loads derived from a nuclear blast environment is presented. The orientation of the vehicle is side-on to the air blast shock front. It is assumed there is no translation at the downwind wheels, i.e., the roll over point. In addition, the vehicle is assumed to behave as a rigid body. That is, the suspension system are taken as rigid, so that the wheels and axles rotate in unison with the body. It can be shown that this assumption slightly overestimates the overturning resistance of vehicles with suspension systems. For a stiff suspension system, such as that of the APC, the rigid body behavior assumption is justified. The only motion possible for this analysis is rotation about the rollover point. The effect of overturning restraint systems has been included in the analysis by incorporating a perfectly plastic vehicle to ground connection on the upwind side of the vehicle. The results give the threshold nuclear environment that just causes overturning. The threshold environment is given in terms of a peak overpressure corresponding to a weapon yield. Results are presented for a range of weapon yields from 1KT to 1MT.

  19. Morphing Unmanned Air Vehicle Intelligent Shape and Flight Control

    E-print Network

    Valasek, John

    Morphing Unmanned Air Vehicle Intelligent Shape and Flight Control John Valasek , Amanda Lampton and demonstrates a complete methodology for the control of a morphing unmanned air vehicle. The shape learning examples of the morphing air vehicle simultaneously tracking a specified trajectory and autonomously

  20. The International Micro Air Vehicle flight competition as autonomy benchmark

    E-print Network

    Visser, Arnoud

    in 1997 at the University of Florida, the same year that the first RoboCup was organized in Nagoya, JapanThe International Micro Air Vehicle flight competition as autonomy benchmark Arnoud Visser vehicles with com- petitions has a long history [1]. The first Micro Air Vehicle competition was organized

  1. Avionics systems design for cooperative unmanned air and ground vehicles

    E-print Network

    Omelchenko, Alexander, 1968-

    2004-01-01

    This thesis summarizes the results of the design of avionics systems intended for use onboard unmanned air and ground vehicles, that are parts of a multi-vehicle system whose primary mission objective is to provide up-close ...

  2. Analysis for SNF Multi Canister Overpack (MCO) Drop into the Cask from the MCO Handling Machine (MHM) with Air Cushion

    SciTech Connect

    RAINS, D.J.

    2000-01-12

    The purpose of this report is to investigate the potential for damage to the MCO during impact from an accidental drop from the MHM into the shipping cask. The MCO is dropped from a height of 8.2 feet above the cask enters the cask concentrically and falls the additional 12.83 feet to the cask bottom. Because of the interface fit between the MCO and the cask and the air entrapment the MCO fall velocity is slowed. The shipping cask is resting on an impact absorber at the time of impact. The energy absorbing properties of the impact absorber are included in this analysis.

  3. Impact of potential electric vehicle market penetration on air quality

    Microsoft Academic Search

    1979-01-01

    Emissions to the air due to electric vehicles will result from several processes during the production, operation, and recycling and disposal of the vehicles. Some of these processes are significantly different than those for conventional vehicles. Mining and manufacturing impacts are different and larger than those for CVs due mainly to battery production and materials preparation. Battery charging will cause

  4. Optimal Planning for Autonomous Air Vehicle Battle Management 1

    E-print Network

    Arslan, Gürdal

    Optimal Planning for Autonomous Air Vehicle Battle Management 1 G¨urdal Arslan, Jonathan D. Wolfe vehicle and ammunition resources to threat clusters in an air to ground campaign. A threat cluster in- cludes a number of different types of threats, which are assumed to cooperate among themselves when

  5. Achieving Acceptable Air Quality: Some Reflections on Controlling Vehicle Emissions

    NASA Astrophysics Data System (ADS)

    Calvert, J. G.; Heywood, J. B.; Sawyer, R. F.; Seinfeld, J. H.

    1993-07-01

    Motor vehicle emissions have been and are being controlled in an effort to abate urban air pollution. This article addresses the question: Will the vehicle exhaust emission control and fuel requirements in the 1990 Clean Air Act Amendments and the California Air Resources Board regulations on vehicles and fuels have a significant impact? The effective control of in-use vehicle emissions is the key to a solution to the motor vehicle part of the urban air pollution problem for the next decade or so. It is not necessary, except perhaps in Southern California, to implement extremely low new car emission standards before the end of the 20th century. Some of the proposed gasoline volatility and composition changes in reformulated gasoline will produce significant reductions in vehicle emissions (for example, reduced vapor pressure, sulfur, and light olefin and improved high end volatility), whereas others (such as substantial oxygenate addition and aromatics reduction) will not.

  6. Photocatalytic destruction of VOCs for in-vehicle air cleaning

    Microsoft Academic Search

    Wan-Kuen Jo; Jung-Hoon Park; Hee-Dong Chun

    2002-01-01

    In order to reduce vehicle occupants’ exposures to aromatic volatile organic compounds (VOCs), it is necessary to develop control strategies for in-vehicle VOCs. This study evaluated the technical feasibility of the application of TiO2 photocatalysis for the removal of VOCs present in air at low parts per billion (ppb) concentrations commonly associated with in-vehicle air quality issues. The photocatalytic removal

  7. Compressed Air Vehicles: A Drive Cycle Analysis of Vehicle Performance, Environmental Impacts, and Economic Costs

    Microsoft Academic Search

    Andrew Papson

    2010-01-01

    In the face of the climate crisis, petroleum dependence, and volatile gasoline prices, it is imperative to explore possible opportunities in unconventional alternative-fuel vehicles. One such option is the Compressed Air Vehicle (CAV), or air car, powered by a pneumatic motor and on-board high-pressure gas tank. While proponents claim CAVs offer environmental and economic benefits over conventional vehicles, the technology

  8. Zinc air battery development for electric vehicles

    NASA Astrophysics Data System (ADS)

    Putt, Ronald A.

    1990-05-01

    This document reports the progress and accomplishments of a 16 month program to develop a rechargeable zinc-air battery for electric vehicle propulsion, from October 1988 through January 1990. The program was the first stage in the transition of alkaline zinc electrode technology, invented at Lawrence Berkeley Laboratory, to private industry. The LBL invention teaches the use of a copper metal foam substrate for the zinc electrode, in combination with forced convection of electrolyte through the foam during battery operation. Research at LBL showed promise that this approach would avoid shape change (densification and dendrite growth), the primary failure mode of this electrode. The program comprised five tasks: (1) cell design, (2) capacity maximization, (3) cycle testing, (4) materials qualification, and (5) a cost/design study. The cell design contemplates a plate and frame stack, with alternating zinc and oxygen electrode frame assemblies between rigid end plates. A 200 Ah cell, as may be required for the EV application, would comprise a stack of five zinc and six oxygen electrode frame/assemblies.

  9. Development of a low-cost crash cushion using recycled automobile tires. Final report

    SciTech Connect

    Habors, D.T.; Hossain, M.

    1998-09-01

    Approximately thirty percent of all vehicle related fatalities that occur each year caused by a single vehicle leaving the road and striking a fixed object; the most common objects struck being trees, guardrails, and utility poles. In many cases current crash cushion systems are not cost effective to be installed on such obstacles. In addition to high initial costs many crash cushions require extensive maintenance or expensive replacement parts driving costs up even more. This makes the development of a more cost-effective crash cushion a necessity. This study proposed an initial design for a low-cost, reusable crash cushion using recycled materials. Used tires and tire-derived materials were tested in both static and dynamic modes to evaluate their application in a crash cushion. Both proved to be able to sustain high loads and durable, making them good candidates for use in a crash cushion. However, the tire-derived pads had excessively high loads per unit deflection prohibiting their use in a crash cushion. This problem could be eliminated if voids were added to allow material to deflect more under loading. The used tires could be used effectively as energy absorbing elements in crash cushions or truck mounted attenuators (TMA`s) if compressed horizontally or vertically.

  10. Looking north Beale Air Force Base, Perimeter Acquisition Vehicle ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking north - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Electric Substation, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  11. Interior Beale Air Force Base, Perimeter Acquisition Vehicle Entry ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Gate House, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  12. Ship motion prediction for launch and recovery of air vehicles

    Microsoft Academic Search

    Ameer Khan; Cees Bil; Kaye E Marion

    2005-01-01

    Due to the random nature of the ship's motion in an open water environment, the deployment and the landing of air vehicles from a ship can often be difficult and even dangerous. The ability to reliably predict the motion will allow improvements in safety on board ships and facilitate more accurate deployment of vehicles off ships. This paper presents an

  13. Ship Motion Prediction for Launch and Recovery of Air Vehicles

    Microsoft Academic Search

    Kaye E Marion

    2009-01-01

    Due to the random nature of the ship's motion in an open water environment, the deployment and the landing of air vehicles from a ship can often be difficult and even dangerous. The ability to reliably predict the motion will allow improvements in safety on board ships and facilitate more accurate deployment of vehicles off ships. This paper presents an

  14. Robotic air vehicle. Blending artificial intelligence with conventional software

    NASA Technical Reports Server (NTRS)

    Mcnulty, Christa; Graham, Joyce; Roewer, Paul

    1987-01-01

    The Robotic Air Vehicle (RAV) system is described. The program's objectives were to design, implement, and demonstrate cooperating expert systems for piloting robotic air vehicles. The development of this system merges conventional programming used in passive navigation with Artificial Intelligence techniques such as voice recognition, spatial reasoning, and expert systems. The individual components of the RAV system are discussed as well as their interactions with each other and how they operate as a system.

  15. Gust mitigation of micro air vehicles using passive articulated wings.

    PubMed

    Oduyela, Adetunji; Slegers, Nathan

    2014-01-01

    Birds and insects naturally use passive flexing of their wings to augment their stability in uncertain aerodynamic environments. In a similar manner, micro air vehicle designers have been investigating using wing articulation to take advantage of this phenomenon. The result is a class of articulated micro air vehicles where artificial passive joints are designed into the lifting surfaces. In order to analyze how passive articulation affects performance of micro air vehicles in gusty environments, an efficient 8 degree-of-freedom model is developed. Experimental validation of the proposed mathematical model was accomplished using flight test data of an articulated micro air vehicle obtained from a high resolution indoor tracking facility. Analytical investigation of the gust alleviation properties of the articulated micro air vehicle model was carried out using simulations with varying crosswind gust magnitudes. Simulations show that passive articulation in micro air vehicles can increase their robustness to gusts within a range of joint compliance. It is also shown that if articulation joints are made too compliant that gust mitigation performance is degraded when compared to a rigid system. PMID:24516368

  16. Innovative decision-making methods for the preliminary design and operations of air-cushion and other marine vehicles

    E-print Network

    Gougoulidis, Georgios

    2011-01-01

    Ship design is a large-scale, multi-level, complex problem that requires decision-making at every stage of the design process. As such, it requires a great deal of time and resources. The evolution of the process of ship ...

  17. Solar panel driven air purging apparatus for motor vehicles

    Microsoft Academic Search

    J. A. Bobier; G. E. Brown

    1992-01-01

    This patent describes improvement in a motor vehicle having an enclosable cabin an internal combustion engine, a battery, an ignition switch having an on position for enabling the internal combustion engine and an off position, an electric motor coupled in driving relationship with an air circulating fan for circulating air through the cabin. The improvement comprises: a solar panel mounted

  18. Adsorption air conditioner for electric vehicle applications. Revision 1

    SciTech Connect

    Aceves, S.M.

    1994-07-27

    This paper shows an analysis of the applicability of an adsorption system for electric vehicle (EV) air conditioning. Adsorption systems are designed and optimized to provide the required cooling for four combinations of vehicle characteristics and driving cycles. The resulting adsorption systems are compared with vapor compression air conditioners that can satisfy the cooling load. The objective function is the overall system weight, which includes the cooling system weight and the weight of the battery necessary to provide energy for air conditioner operation. The system with the minimum overall weight is considered to be the best, because a lower weight results in an increased vehicle range. The results indicate that, for the conditions analyzed in this paper, vapor compression air conditioners are superior to adsorption systems not only because they are lighter, but also because they have a higher COP and are more compact.

  19. Development of an optimal impact energy absorber for highway crash cushions

    E-print Network

    Michalec, Christopher Ryan

    2005-11-01

    The objective of this research is to develop a new and efficient method of absorbing a vehicle??s kinetic energy for highway safety crash cushions. A vehicle that makes a direct impact with a rigid highway structure traveling at highway speeds can...

  20. Flexible Wing Base Micro Aerial Vehicles: Assessment of Controllability of Micro Air Vehicles

    NASA Technical Reports Server (NTRS)

    Jenkins, David A.; Ifju, Peter G.; Abdulrahim, Mujahid; Olipra, Scott

    2002-01-01

    In the last several years, we have developed unique types of micro air vehicles that utilize flexible structures and extensible covering materials. These MAVs can be operated with maximum dimensions as small as 6 inches and carry reasonable payloads, such as video cameras and transmitters. We recently demonstrated the potential of these vehicles by winning the Fourth International Micro Air Vehicle Competition, held at Ft. Huachucha, Arizona in May 2000. The pilots report that these vehicles have unusually smooth flying characteristics and are relatively easy to fly, both in the standard RC mode and "through the camera" when at greater distances. In comparison, they find that similar sized vehicles with more conventional rigid construction require much more input from the pilot just to maintain control. To make these subjective observations more quantitative, we have devised a system that can conveniently record a complete history of all the RC transmitter stick movements during a flight. Post-flight processing of the stick movement data allows for direct comparisons between different types of MAVs when flown by the same pilot, and also comparisons between pilots. Eventually, practical micro air vehicles will be autonomously controlled, but we feel that the smoothest flying and easiest to fly embodiments will also be the most successful in the long run. Comparisons between several types of micro air vehicles will be presented, along with interpretations of the data.

  1. Effect of Intake Air Filter Condition on Vehicle Fuel Economy

    SciTech Connect

    Norman, Kevin M [ORNL; Huff, Shean P [ORNL; West, Brian H [ORNL

    2009-02-01

    The U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy and the U.S. Environmental Protection Agency (EPA) jointly maintain a fuel economy website (www.fueleconomy.gov), which helps fulfill their responsibility under the Energy Policy Act of 1992 to provide accurate fuel economy information [in miles per gallon (mpg)] to consumers. The site provides information on EPA fuel economy ratings for passenger cars and light trucks from 1985 to the present and other relevant information related to energy use such as alternative fuels and driving and vehicle maintenance tips. In recent years, fluctuations in the price of crude oil and corresponding fluctuations in the price of gasoline and diesel fuels have renewed interest in vehicle fuel economy in the United States. (User sessions on the fuel economy website exceeded 20 million in 2008 compared to less than 5 million in 2004 and less than 1 million in 2001.) As a result of this renewed interest and the age of some of the references cited in the tips section of the website, DOE authorized the Oak Ridge National Laboratory (ORNL) Fuels, Engines, and Emissions Research Center (FEERC) to initiate studies to validate and improve these tips. This report documents a study aimed specifically at the effect of engine air filter condition on fuel economy. The goal of this study was to explore the effects of a clogged air filter on the fuel economy of vehicles operating over prescribed test cycles. Three newer vehicles (a 2007 Buick Lucerne, a 2006 Dodge Charger, and a 2003 Toyota Camry) and an older carbureted vehicle were tested. Results show that clogging the air filter has no significant effect on the fuel economy of the newer vehicles (all fuel injected with closed-loop control and one equipped with MDS). The engine control systems were able to maintain the desired AFR regardless of intake restrictions, and therefore fuel consumption was not increased. The carbureted engine did show a decrease in fuel economy with increasing restriction. However, the level of restriction required to cause a substantial (10-15%) decrease in fuel economy (such as that cited in the literature) was so severe that the vehicle was almost undrivable. Acceleration performance on all vehicles was improved with a clean air filter. Once it was determined how severe the restriction had to be to affect the carbureted vehicle fuel economy, the 2007 Buick Lucerne was retested in a similar manner. We were not able to achieve the level of restriction that was achieved with the 1972 Pontiac with the Lucerne. The Lucerne's air filter box would not hold the filter in place under such severe conditions. (It is believed that this testing exceeded the design limits of the air box.) Tests were conducted at a lower restriction level (although still considerably more severe than the initial clogged filter testing), allowing the air filter to stay seated in the air box, and no significant change was observed in the Lucerne's fuel economy or the AFR over the HFET cycle. Closed-loop control in modern fuel injected vehicle applications is sophisticated enough to keep a clogged air filter from affecting the vehicle fuel economy. However for older, open-loop, carbureted vehicles, a clogged air filter can affect the fuel economy. For the vehicle tested, the fuel economy with a new air filter improved as much as 14% over that with a severely clogged filter (in which the filter was so clogged that drivability was impacted). Under a more typical state of clog, the improvement with a new filter ranged from 2 to 6%.

  2. Department of Mechanical Engineering Spring 2011 General Motors 2 Variable Height Vehicle Air Dam

    E-print Network

    Demirel, Melik C.

    Vehicle Air Dam Overview The fundamental issue with fixed air dams is the bottom edge of the dam needs to be high enough to meet defined vehicle ground clearance and front approach angle criteria. Air dams must a solution to this problem by designing an variable height vehicle air dam. Objectives Our mission

  3. Non-refrigerant thermoelectric air conditioning technique on vehicles

    Microsoft Academic Search

    Chung-Yen Hsu; Sheng-Liang Li; Chun-Kai Liu; Ra-Min Tain; Heng-Chieh Chien; Shi-Feng Hsu; Chih-Ming Tzeng; Ming-Ji Dai; Hsu-Shen Chu; Jenn-Dong Hwang

    2011-01-01

    An electrical compressor technique of thermoelectric (TE) based climate control system in passenger vehicles provides solid state design and construction, non-refrigerants and the ability of providing faster time to comfort, beltless solution that enables engine-off air conditioner operation and modified the adversely impact by belt-driven vapor compression air conditioners, improved efficiency of positive temperature coefficient (PTC) heater systems. A complete

  4. Study of long term options for electric vehicle air conditioning

    SciTech Connect

    Dieckmann, J.; Mallory, D. (Little (Arthur D.), Inc., Cambridge, MA (United States))

    1991-07-01

    There are strong incentives in terms of national energy and environmental policy to encourage the commercialization of electrically powered vehicles in the U.S. Among these incentives are reduced petroleum consumption, improved electric generation capacity utilization, reduced IC engine emissions, and, depending on the primary fuel used for electric power generation, reduced emissions of carbon dioxide. A basic requirement for successfully commercializing any motor vehicle in the US is provision of adequate passenger comfort heating and air conditioning (cooling). Although air conditioning is generally sold as optional equipment, in excess of 80% of the automobiles and small trucks sold in the US have air conditioning systems. In current, pre-commercial electric vehicles, comfort heating is provided by a liquid fuel fired heater that heats water which is circulated through the standard heater core in the conventional interior air handling unit. Air conditioning is provided by electric motor driven compressors, installed in a system having, perhaps, an [open quotes]upsized[close quotes] condenser and a standard evaporator (front and rear evaporators in some instances) installed in the conventional interior air handler. Although this approach is adequate in the near term for initial commercialization efforts, a number of shortcomings of this arrangement, as well as longer range concerns need to be addressed. In this project, the long term alternatives for cooling and heating electric vehicles effectively, efficiently (with minimum range penalties), and without adverse environmental impacts have been examined. Identification of options that can provide both heating and cooling is important, in view of the disadvantages of carrying separate heating and cooling systems in the vehicle.

  5. Study of long term options for electric vehicle air conditioning

    SciTech Connect

    Dieckmann, J.; Mallory, D. [Little (Arthur D.), Inc., Cambridge, MA (United States)

    1991-07-01

    There are strong incentives in terms of national energy and environmental policy to encourage the commercialization of electrically powered vehicles in the U.S. Among these incentives are reduced petroleum consumption, improved electric generation capacity utilization, reduced IC engine emissions, and, depending on the primary fuel used for electric power generation, reduced emissions of carbon dioxide. A basic requirement for successfully commercializing any motor vehicle in the US is provision of adequate passenger comfort heating and air conditioning (cooling). Although air conditioning is generally sold as optional equipment, in excess of 80% of the automobiles and small trucks sold in the US have air conditioning systems. In current, pre-commercial electric vehicles, comfort heating is provided by a liquid fuel fired heater that heats water which is circulated through the standard heater core in the conventional interior air handling unit. Air conditioning is provided by electric motor driven compressors, installed in a system having, perhaps, an {open_quotes}upsized{close_quotes} condenser and a standard evaporator (front and rear evaporators in some instances) installed in the conventional interior air handler. Although this approach is adequate in the near term for initial commercialization efforts, a number of shortcomings of this arrangement, as well as longer range concerns need to be addressed. In this project, the long term alternatives for cooling and heating electric vehicles effectively, efficiently (with minimum range penalties), and without adverse environmental impacts have been examined. Identification of options that can provide both heating and cooling is important, in view of the disadvantages of carrying separate heating and cooling systems in the vehicle.

  6. A pressure control scheme for air brakes in commercial vehicles 

    E-print Network

    Bowlin, Christopher Leland

    2007-04-25

    This research is focused on developing a control scheme for regulating the pressure in the brake chamber of an air brake system found in most commercial vehicles like trucks, tractor-trailers and buses. Such a control scheme can be used...

  7. Honeywell's organic air vehicle chemical-biological sensing platform

    Microsoft Academic Search

    Barry E. Cole; Brian Krafthefer; Daniel Knee; Vaughn M. Fulton; Kristen Law

    2004-01-01

    Unmanned air vehicles (UAVs) today are mostly used for reconnaissance and sometimes weapons delivery. Remote sensing of chemical-biological (CB) agents is another beneficial use of UAVs. While remote sensing of CB agents can be done by LIDAR spectroscopy, this technology is less spatially precise and less sensitive than actual measurements on a collected sample. One family of UAVs of particularly

  8. Development of vehicle magnetic air conditioner (VMAC) technology. Final report

    SciTech Connect

    Gschneidner, Karl A., Jr.; Pecharsky, V.K.; Jiles, David; Zimm, Carl B.

    2001-08-28

    The objective of Phase I was to explore the feasibility of the development of a new solid state refrigeration technology - magnetic refrigeration - in order to reduce power consumption of a vehicle air conditioner by 30%. The feasibility study was performed at Iowa State University (ISU) together with Astronautics Corporation of America Technology Center (ACATC), Madison, WI, through a subcontract with ISU.

  9. Nonlinear Trajectory Generation for Unmanned Air Vehicles with Multiple Radars

    E-print Network

    Murray, Richard M.

    Nonlinear Trajectory Generation for Unmanned Air Vehicles with Multiple Radars Tamer Inanc, Kathy Misovec and Richard M. Murray Abstract-- The problem of finding a real time optimal trajectory to minimize on low observable trajectory generation in three ways. First, trajectory planning in the presence

  10. On-Line Situation Assessment for Unmanned Air Vehicles

    Microsoft Academic Search

    Mark L. Hanson; Olga Sullivan; Karen A. Harper

    2001-01-01

    Future conflicts may involve composite striker packages composed of manned and unmanned air vehicles (UAVs) supervised by mission controllers. Since situation awareness (SA) contributes to and is a crucial part of mission success, significant effort is now being placed on developing new technologies that have the potential of increasing SA for the mission controller. This paper describes the design and

  11. Autonomous terrain-following for unmanned air vehicles

    Microsoft Academic Search

    Raza Samar; Abdur Rehman

    2011-01-01

    This paper presents an integrated guidance and control design scheme for an unmanned air vehicle (UAV), and its flight test results. The paper focuses on the longitudinal control and guidance aspects, with particular emphasis on the terrain-following problem. An introduction to the mission, and the terrain-following problem is given first. Waypoints for climb and descent are defined. Computation of the

  12. Research of Autonomous landing control of unmanned combat air vehicle

    Microsoft Academic Search

    Shaoyan Li; Zongji Chen

    2003-01-01

    This paper is to present a robust controller design method for developing autonomous landing systems of Unmanned Combat Air Vehicle (UCAV). We first analyze the characteristic of autonomous landing of UCAV, and put forward its landing performance specifications. Structure singular value mu| synthesis is used to develop autonomous landing systems to accurately follow the pre-designed ideal landing track or online

  13. A zinc-air battery and flywheel zero emission vehicle

    SciTech Connect

    Tokarz, F.; Smith, J.R.; Cooper, J.; Bender, D.; Aceves, S.

    1995-10-03

    In response to the 1990 Clean Air Act, the California Air Resources Board (CARB) developed a compliance plan known as the Low Emission Vehicle Program. An integral part of that program was a sales mandate to the top seven automobile manufacturers requiring the percentage of Zero Emission Vehicles (ZEVs) sold in California to be 2% in 1998, 5% in 2001 and 10% by 2003. Currently available ZEV technology will probably not meet customer demand for range and moderate cost. A potential option to meet the CARB mandate is to use two Lawrence Livermore National Laboratory (LLNL) technologies, namely, zinc-air refuelable batteries (ZARBs) and electromechanical batteries (EMBs, i. e., flywheels) to develop a ZEV with a 384 kilometer (240 mile) urban range. This vehicle uses a 40 kW, 70 kWh ZARB for energy storage combined with a 102 kW, 0.5 kWh EMB for power peaking. These technologies are sufficiently near-term and cost-effective to plausibly be in production by the 1999-2001 time frame for stationary and initial vehicular applications. Unlike many other ZEVs currently being developed by industry, our proposed ZEV has range, acceleration, and size consistent with larger conventional passenger vehicles available today. Our life-cycle cost projections for this technology are lower than for Pb-acid battery ZEVs. We have used our Hybrid Vehicle Evaluation Code (HVEC) to simulate the performance of the vehicle and to size the various components. The use of conservative subsystem performance parameters and the resulting vehicle performance are discussed in detail.

  14. Comparative analysis of aluminum-air battery propulsion systems for passenger vehicles

    NASA Astrophysics Data System (ADS)

    Salisbury, J. D.; Behrin, E.; Kong, M. K.; Whisler, D. J.

    1980-02-01

    Three electric propulsion systems using an aluminum air battery were analyzed and compared to the internal combustion engine (ICE) vehicle. The engine and fuel systems of a representative five passenger highway vehicle were replaced conceptually by each of the three electric propulsion systems. The electrical vehicles were constrained by the computer simulation to be equivalent to the ICE vehicle in range and acceleration performance. The vehicle masses and aluminum consumption rates were then calculated for the electric vehicles and these data were used as figures of merit. The Al-air vehicles analyzed were (1) an Al-air battery only electric vehicle; (2) an Al-air battery combined with a nickel zinc secondary battery for power leveling and regenerative braking; and (3) an Al-air battery combined with a flywheel for power leveling and regenerative braking. All three electric systems compared favorably with the ICE vehicle.

  15. Multipurpose Uninhabited Air Vehicle (UAV) design and verification

    NASA Astrophysics Data System (ADS)

    Barquero, Juan P.

    A multipurpose Uninhabited Air Vehicle was designed and built for the NASA University Research Center. It is capable of carrying a payload of up to 14 lbs with an estimated endurance of 3 hours. This thesis will describe the work that was completed on the aerodynamic and preliminary structural design of the air vehicle. It will be demonstrated how the size and configuration of the airframe were chosen based on the design requirements. The detailed design process will be described to achieve initial performance and mission requirements. Although the URC has successfully constructed airframes in the past, it is the intention of this thesis to also take a different approach on alternative construction methods in an effort to reduce cost and improve aircraft performance.

  16. Attachment device for an inflatable protective cushion

    DOEpatents

    Nelsen, James M. (Albuquerque, NM); Luna, Daniel A. (Los Lunas, NM); Gwinn, Kenneth W. (Cedar Crest, NM)

    1998-01-01

    An inflatable cushion assembly for use with an inflator comprises an inflatable cushion having an inner surface, outer surface, and at least one protrusion extending from one of the inner or outer surfaces. The inflatable cushion defines an opening between the inner surface and the outer surface for receiving the inflator. An attachment member contacts the one of the inner or outer surfaces adjacent the opening and includes a groove for receiving the protrusion, the attachment member securing the inflator within the opening.

  17. A Compact Millimeter Wave Radar Sensor for Unmanned Air Vehicles

    Microsoft Academic Search

    Ali Göktogan; Graham Brooker; Salah Sukkarieh

    2003-01-01

    This paper presents a compact Millimeter Wave (MMW) radar unit that has been developed to be used as a Range, Bearing and\\u000a Elevation (RBE) sensor on the Brumby Mk III Unmanned Air Vehicles (UAV). The Brumby MkIII is the flight platform used in the\\u000a Autonomous Navigation and Sensing Experimental Research (ANSER) project which is focused on the development and demonstration

  18. Design of Electrical Air-Condition Control System for Fuel Cell Vehicle Based on CAN Bus

    Microsoft Academic Search

    Hui Chen; Lin Zhan

    2010-01-01

    This paper introduces the principle of controller area network (CAN) bus and the structure of fuel cell vehicle control system based on CAN bus. It focuses on electrical air -condition control system for fuel cell vehicle based on CAN bus, which consists of an air condition control node and an air condition compressor drive. The design of electrical air condition

  19. Air liquefaction and enrichment system propulsion in reusable launch vehicles

    NASA Astrophysics Data System (ADS)

    Bond, W. H.; Yi, A. C.

    1994-07-01

    A concept is shown for a fully reusable, Earth-to-orbit launch vehicle with horizontal takeoff and landing, employing an air-turborocket for low speed and a rocket for high-speed acceleration, both using liquid hydrogen for fuel. The turborocket employs a modified liquid air cycle to supply the oxidizer. The rocket uses 90% pure liquid oxygen as its oxidizer that is collected from the atmosphere, separated, and stored during operation of the turborocket from about Mach 2 to 5 or 6. The takeoff weight and the thrust required at takeoff are markedly reduced by collecting the rocket oxidizer in-flight. This article shows an approach and the corresponding technology needs for using air liquefaction and enrichment system propulsion in a single-stage-to-orbit (SSTO) vehicle. Reducing the trajectory altitude at the end of collection reduces the wing area and increases payload. The use of state-of-the-art materials, such as graphite polyimide, in a direct substitution for aluminum or aluminum-lithium alloy, is critical to meet the structure weight objective for SSTO. Configurations that utilize 'waverider' aerodynamics show great promise to reduce the vehicle weight.

  20. 21 CFR 890.3175 - Flotation cushion.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3175 Flotation cushion. (a) Identification. A flotation...

  1. 21 CFR 890.3175 - Flotation cushion.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3175 Flotation cushion. (a) Identification. A flotation...

  2. 21 CFR 890.3175 - Flotation cushion.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3175 Flotation cushion. (a) Identification. A...

  3. 21 CFR 890.3175 - Flotation cushion.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3175 Flotation cushion. (a) Identification. A...

  4. 21 CFR 890.3175 - Flotation cushion.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3175 Flotation cushion. (a) Identification. A...

  5. Optimization of Vehicle Air Conditioning Systems Using Transient Air Conditioning Performance Analysis

    Microsoft Academic Search

    Terry J. Hendricks

    The National Renewable Energy Laboratory (NREL) has developed a transient air conditioning (A\\/C) system model using SINDA\\/FLUINT analysis software. It captures all the relevant physics of transient A\\/C system performance, including two-phase flow effects in the evaporator and condenser, system mass effects, air side heat transfer on the condenser\\/evaporator, vehicle speed effects, temperature-dependent properties, and integration with a simplified cabin

  6. High specific energy and specific power aluminum/air battery for micro air vehicles

    NASA Astrophysics Data System (ADS)

    Kindler, A.; Matthies, L.

    2014-06-01

    Micro air vehicles developed under the Army's Micro Autonomous Systems and Technology program generally need a specific energy of 300 - 550 watt-hrs/kg and 300 -550 watts/kg to operate for about 1 hour. At present, no commercial cell can fulfill this need. The best available commercial technology is the Lithium-ion battery or its derivative, the Li- Polymer cell. This chemistry generally provides around 15 minutes flying time. One alternative to the State-of-the Art is the Al/air cell, a primary battery that is actually half fuel cell. It has a high energy battery like aluminum anode, and fuel cell like air electrode that can extract oxygen out of the ambient air rather than carrying it. Both of these features tend to contribute to a high specific energy (watt-hrs/kg). High specific power (watts/kg) is supported by high concentration KOH electrolyte, a high quality commercial air electrode, and forced air convection from the vehicles rotors. The performance of this cell with these attributes is projected to be 500 watt-hrs/kg and 500 watts/kg based on simple model. It is expected to support a flying time of approximately 1 hour in any vehicle in which the usual limit is 15 minutes.

  7. Projection Moire Interferometry Measurements of Micro Air Vehicle Wings

    NASA Technical Reports Server (NTRS)

    Fleming, Gary A.; Bartram, Scott M.; Waszak, Martin R.; Jenkins, Luther N.

    2001-01-01

    Projection Moire Interferometry (PMI) has been used to measure the structural deformation of micro air vehicle (MAV) wings during a series of wind tunnel tests. The MAV wings had a highly flexible wing structure, generically reminiscent of a bat s wing, which resulted in significant changes in wing shape as a function of MAV angle-of-attack and simulated flight speed. This flow-adaptable wing deformation is thought to provide enhanced vehicle stability and wind gust alleviation compared to rigid wing designs. Investigation of the potential aerodynamic benefits of a flexible MAV wing required measurement of the wing shape under aerodynamic loads. PMI was used to quantify the aerodynamically induced changes in wing shape for three MAV wings having different structural designs and stiffness characteristics. This paper describes the PMI technique, its application to MAV testing, and presents a portion of the PMI data acquired for the three different MAV wings tested.

  8. Avionics and control system development for mid-air rendezvous of two unmanned aerial vehicles

    E-print Network

    Park, Sanghyuk, 1973-

    2004-01-01

    A flight control system was developed to achieve mid-air rendezvous of two unmanned aerial vehicles (UAVs) as a part of the Parent Child Unmanned Aerial Vehicle (PCUAV) project at MIT and the Draper Laboratory. A lateral ...

  9. Research of autonomous landing control of unmanned combat air vehicle

    NASA Astrophysics Data System (ADS)

    Li, Shaoyan; Chen, Zongji

    2003-09-01

    This paper is to present a robust controller design method for developing autonomous landing systems of Unmanned Combat Air Vehicle (UCAV). We first analyze the characteristic of autonomous landing of UCAV, and put forward its landing performance specifications. Structure singular value ?| synthesis is used to develop autonomous landing systems to accurately follow the pre-designed ideal landing track or online generated optimal landing track. The robust performance of system is analyzed. The simulation results demonstrate that the designed autonomous landing system satisfies the performance requirements of autonomous landing of UCAV when there are uncertainties of UCAV aircraft model, measurement noises and exogenous disturbances.

  10. Improving the aluminum-air battery system for use in electrical vehicles

    Microsoft Academic Search

    Shaohua Yang

    2003-01-01

    The objectives of this study include improvement of the efficiency of the aluminum\\/air battery system and demonstration of its ability for vehicle applications. The aluminum\\/air battery system can generate enough energy and power for driving ranges and acceleration similar to that of gasoline powered cars. Therefore has the potential to be a power source for electrical vehicles. Aluminum\\/air battery vehicle

  11. Reinforcement of silicone cushions using silica fillers

    SciTech Connect

    Shell, P.K.; Jessop, E.S.; McKinley, B.M.

    1985-09-20

    Cushions prepared with fillers pretreated with wetting agents were much easier to process in all stages of production except for sheeting prior to bin aging. However, the use of these pre-wetted fillers resulted in an unacceptable increase in compression set. The processability of cushions containing fillers integrally treated with either wetting or coupling agents was no different from that of cushions containing untreated fillers. However, cushions prepared with the integral addition of a vinyl coupling agent did not show the increase in compression set that was so prevalent in the cushions made with pre-wetted fillers. This suggests that pretreating the fillers with coupling agents may improve the processability without cost to the final cushion properties. The data collected indicated that the use of Hi Sil with these surface modifiers appears to have no effect apart from altering the total filler loading. Y1587 not only softens the final cushions, it also appears to contribute significantly to the compression set. The ease in handling pretreated fillers could eliminate the need for a processing aid like Y1587, thus providing a possible means for reducing compression set.

  12. Updraft Model for Development of Autonomous Soaring Uninhabited Air Vehicles

    NASA Technical Reports Server (NTRS)

    Allen, Michael J.

    2006-01-01

    Large birds and glider pilots commonly use updrafts caused by convection in the lower atmosphere to extend flight duration, increase cross-country speed, improve range, or simply to conserve energy. Uninhabited air vehicles may also have the ability to exploit updrafts to improve performance. An updraft model was developed at NASA Dryden Flight Research Center (Edwards, California) to investigate the use of convective lift for uninhabited air vehicles in desert regions. Balloon and surface measurements obtained at the National Oceanic and Atmospheric Administration Surface Radiation station (Desert Rock, Nevada) enabled the model development. The data were used to create a statistical representation of the convective velocity scale, w*, and the convective mixing-layer thickness, zi. These parameters were then used to determine updraft size, vertical velocity profile, spacing, and maximum height. This paper gives a complete description of the updraft model and its derivation. Computer code for running the model is also given in conjunction with a check case for model verification.

  13. GPS Auto-Navigation Design for Unmanned Air Vehicles

    NASA Technical Reports Server (NTRS)

    Nilsson, Caroline C. A.; Heinzen, Stearns N.; Hall, Charles E., Jr.; Chokani, Ndaona

    2003-01-01

    A GPS auto-navigation system is designed for Unmanned Air Vehicles. The objective is to enable the air vehicle to be used as a test-bed for novel flow control concepts. The navigation system uses pre-programmed GPS waypoints. The actual GPS position, heading, and velocity are collected by the flight computer, a PC104 system running in Real-Time Linux, and compared with the desired waypoint. The navigator then determines the necessity of a heading correction and outputs the correction in the form of a commanded bank angle, for a level coordinated turn, to the controller system. This controller system consists of 5 controller! (pitch rate PID, yaw damper, bank angle PID, velocity hold, and altitude hold) designed for a closed loop non-linear aircraft model with linear aerodynamic coefficients. The ability and accuracy of using GPS data, is validated by a GPS flight. The autopilots are also validated in flight. The autopilot unit flight validations show that the designed autopilots function as designed. The aircraft model, generated on Matlab SIMULINK is also enhanced by the flight data to accurately represent the actual aircraft.

  14. Attachment device for an inflatable protective cushion

    DOEpatents

    Nelsen, J.M.; Luna, D.A.; Gwinn, K.W.

    1998-12-08

    An inflatable cushion assembly for use with an inflator comprises an inflatable cushion having an inner surface, outer surface, and at least one protrusion extending from one of the inner or outer surfaces. The inflatable cushion defines an opening between the inner surface and the outer surface for receiving the inflator. An attachment member contacts the one of the inner or outer surfaces adjacent the opening and includes a groove for receiving the protrusion, the attachment member securing the inflator within the opening. 22 figs.

  15. Research Positionsfor Development of Novel Green Air Conditioning and Refrigeration Systems for Transportation Vehicles

    E-print Network

    Bahrami, Majid

    Research Positionsfor Development of Novel Green Air Conditioning and Refrigeration Systems and is related to development of new green airconditioning and refrigeration (A/CR) technologies for longhaul insulation technology for service vehicles; iii) Simulation and development of air distribution

  16. Foam-filled cushions for sliding trays

    NASA Technical Reports Server (NTRS)

    Nahin, S. B.; Robb, P. H.

    1980-01-01

    Polytetrafluoroethylene tube filled with polyurethane foam forms low friction sliding surface that cushions vibrations and absorbs manufacturing tolerances and misalignment. Possible uses include packaging of components for shipping and seals for doors in lockers, cars, and refrigerators.

  17. Flexible Wing Base Micro Aerial Vehicles: Composite Materials for Micro Air Vehicles

    NASA Technical Reports Server (NTRS)

    Ifju, Peter G.; Ettinger, Scott; Jenkins, David; Martinez, Luis

    2002-01-01

    This paper will discuss the development of the University of Florida's Micro Air Vehicle concept. A series of flexible wing based aircraft that possess highly desirable flight characteristics were developed. Since computational methods to accurately model flight at the low Reynolds numbers associated with this scale are still under development, our effort has relied heavily on trial and error. Hence a time efficient method was developed to rapidly produce prototype designs. The airframe and wings are fabricated using a unique process that incorporates carbon fiber composite construction. Prototypes can be fabricated in around five man-hours, allowing many design revisions to be tested in a short period of time. The resulting aircraft are far more durable, yet lighter, than their conventional counterparts. This process allows for thorough testing of each design in order to determine what changes were required on the next prototype. The use of carbon fiber allows for wing flexibility without sacrificing durability. The construction methods developed for this project were the enabling technology that allowed us to implement our designs. The resulting aircraft were the winning entries in the International Micro Air Vehicle Competition for the past two years. Details of the construction method are provided in this paper along with a background on our flexible wing concept.

  18. Cleaning the air and improving health with hydrogen fuel-cell vehicles

    Microsoft Academic Search

    M. Z. Jacobson; W. G. Colella; D. M. Golden

    2005-01-01

    Converting all U.S. onroad vehicles to hydrogen fuel-cell vehicles (HFCVs) may improve air quality, health, and climate significantly, whether the hydrogen is produced by steam reforming of natural gas, wind electrolysis, or coal gasification. Most benefits would result from eliminating current vehicle exhaust. Wind and natural gas HFCVs offer the greatest potential health benefits and could save 3700 to 6400

  19. Q-Learning Approach to Automated Unmanned Air Vehicle (UAV) Demining

    E-print Network

    Ferrari, Silvia

    Q-Learning Approach to Automated Unmanned Air Vehicle (UAV) Demining Silvia Ferrari and Greyson to Unmanned Air Vehicle (UAV) navigation, or path planning, for sensing applications in which an infrared (IR) sensor or camera is installed onboard the UAV for the purpose of detecting and classifying multiple

  20. An analytical comparison of adsorption and vapor compression air conditioners for electric vehicle applications

    Microsoft Academic Search

    S. M. Aceves

    1996-01-01

    This paper shows an analysis of the applicability of an adsorption system for electric vehicle (EV) air conditioning. Adsorption systems are designed and optimized to provide the required cooling for four combinations of vehicle characteristics and driving cycles. The resulting adsorption systems are compared with vapor compression air conditioners that can satisfy the cooling load. The objective function is the

  1. Development and testing of an unmanned air vehicle telemetry system

    NASA Astrophysics Data System (ADS)

    Wilhelm, Kevin T.

    1991-09-01

    Unmanned air vehicles (UAV's) provide a low-cost, low-maintenance, and effective platform upon which experimentation can be performed to validate conceptual aerodynamic ideas. However, the UAV flight test data acquisition process is complex and requires a reliable recording system for post-flight data analysis. The thrust of this thesis was the development, construction, and validation of a viable telemetry system for data gathering and processing. Major areas of focus were: integration of the telemetry into a 1/8 scale model, radio controlled F-16A airplane; telemetry circuitry optimization; recording and display of instrumented parameters; and data reduction techniques necessary to obtain useful information. A flight test was flown and data was gathered using a steady-heading side-slip maneuver to demonstrate successful integration of all supporting elements.

  2. Air pollution and health risks due to vehicle traffic

    PubMed Central

    Zhang, Kai; Batterman, Stuart

    2014-01-01

    Traffic congestion increases vehicle emissions and degrades ambient air quality, and recent studies have shown excess morbidity and mortality for drivers, commuters and individuals living near major roadways. Presently, our understanding of the air pollution impacts from congestion on roads is very limited. This study demonstrates an approach to characterize risks of traffic for on- and near-road populations. Simulation modeling was used to estimate on- and near-road NO2 concentrations and health risks for freeway and arterial scenarios attributable to traffic for different traffic volumes during rush hour periods. The modeling used emission factors from two different models (Comprehensive Modal Emissions Model and Motor Vehicle Emissions Factor Model version 6.2), an empirical traffic speed–volume relationship, the California Line Source Dispersion Model, an empirical NO2–NOx relationship, estimated travel time changes during congestion, and concentration–response relationships from the literature, which give emergency doctor visits, hospital admissions and mortality attributed to NO2 exposure. An incremental analysis, which expresses the change in health risks for small increases in traffic volume, showed non-linear effects. For a freeway, “U” shaped trends of incremental risks were predicted for on-road populations, and incremental risks are flat at low traffic volumes for near-road populations. For an arterial road, incremental risks increased sharply for both on- and near-road populations as traffic increased. These patterns result from changes in emission factors, the NO2–NOx relationship, the travel delay for the on-road population, and the extended duration of rush hour for the near-road population. This study suggests that health risks from congestion are potentially significant, and that additional traffic can significantly increase risks, depending on the type of road and other factors. Further, evaluations of risk associated with congestion must consider travel time, the duration of rush-hour, congestion-specific emission estimates, and uncertainties. PMID:23500830

  3. Air pollution and health risks due to vehicle traffic.

    PubMed

    Zhang, Kai; Batterman, Stuart

    2013-04-15

    Traffic congestion increases vehicle emissions and degrades ambient air quality, and recent studies have shown excess morbidity and mortality for drivers, commuters and individuals living near major roadways. Presently, our understanding of the air pollution impacts from congestion on roads is very limited. This study demonstrates an approach to characterize risks of traffic for on- and near-road populations. Simulation modeling was used to estimate on- and near-road NO2 concentrations and health risks for freeway and arterial scenarios attributable to traffic for different traffic volumes during rush hour periods. The modeling used emission factors from two different models (Comprehensive Modal Emissions Model and Motor Vehicle Emissions Factor Model version 6.2), an empirical traffic speed-volume relationship, the California Line Source Dispersion Model, an empirical NO2-NOx relationship, estimated travel time changes during congestion, and concentration-response relationships from the literature, which give emergency doctor visits, hospital admissions and mortality attributed to NO2 exposure. An incremental analysis, which expresses the change in health risks for small increases in traffic volume, showed non-linear effects. For a freeway, "U" shaped trends of incremental risks were predicted for on-road populations, and incremental risks are flat at low traffic volumes for near-road populations. For an arterial road, incremental risks increased sharply for both on- and near-road populations as traffic increased. These patterns result from changes in emission factors, the NO2-NOx relationship, the travel delay for the on-road population, and the extended duration of rush hour for the near-road population. This study suggests that health risks from congestion are potentially significant, and that additional traffic can significantly increase risks, depending on the type of road and other factors. Further, evaluations of risk associated with congestion must consider travel time, the duration of rush-hour, congestion-specific emission estimates, and uncertainties. PMID:23500830

  4. Analysis of the AirTouch automatic vehicle location system's ability to locate moving vehicles 

    E-print Network

    Henry, Tracy Lynn

    1995-01-01

    Automatic vehicle location systems are becoming more prevalent in diverse transportation applications. Their ability to locate vehicles can assist in locating emergency and public transit vehicles for better real-time dispatching as well...

  5. Air Quality Impacts of Some Alternative Vehicle Options UC Irvine National Fuel Cell Research Center 1 March 28, 2008

    E-print Network

    Dabdub, Donald

    Air Quality Impacts of Some Alternative Vehicle Options UC Irvine National Fuel Cell Research of California, Irvine (UCI) #12;Air Quality Impacts of Some Alternative Vehicle Options UC Irvine National Fuel.......................................................................................................... 37 #12;Air Quality Impacts of Some Alternative Vehicle Options UC Irvine National Fuel Cell Research

  6. Development and evaluation of a universal contoured cushion.

    PubMed

    Perkash, I; O'Neill, H; Politi-Meeks, D; Beets, C L

    1984-12-01

    A new wheelchair seat cushion has been developed which reduces the ischaemia producing forces and redistributes them to the more tolerant areas of the posterior thighs and lateral gluteal muscles. The cushion is fabricated of foam materials and designed to stabilise the pelvis and promote proper spinal-pelvic alignment. Pressure measurements were recorded at the skin cushion interface for 66 subjects while seated on the cushion in their own wheelchair. The cushion was considered effective if maximum interface pressures recorded were: coccyx: less than 20 mmHg, ischii: less than 65 mmHg, trochanters: less than 70 mmHg, and posterior thighs: less than 80 mmHg. The cushion was considered ineffective if the interface pressure at any one location exceeded these criteria. The cushion was found effective for 52 of the subjects. The cushion was more effective (90 per cent versus 58 per cent) for subjects without certain skeletal deformities (pelvic obliquity, bony resections). Eighty-three per cent of the respondents who were followed on the cushion reported that they preferred the cushion to their previous cushions with improved posture, balance and comfort being the most commonly cited reasons. This study has shown the cushion to be a preferred alternative to other commercially available wheelchair cushions for those who are paraplegic. PMID:6522089

  7. Dynamics, stability, and control analyses of flapping wing micro-air vehicles

    NASA Astrophysics Data System (ADS)

    Orlowski, Christopher T.; Girard, Anouck R.

    2012-05-01

    The paper presents an overview of the various analyses of flight dynamics, stability, and control of flapping wing micro-air vehicles available in the literature. The potential benefits of flapping wing micro-air vehicles for civil, military, and search and rescue operations are numerous. The majority of the flight dynamics research involves the standard aircraft (6DOF) equations of motion, although a growth is evident in examining the multibody flight dynamics models of flapping wing micro-air vehicles. The stability of flapping wing micro-air vehicles is largely studied in the vicinity of hover and forward flight. The majority of stability studies focus on linear, time-invariant stability in the vicinity of reference flight conditions, such as hover or forward flight. The consistent result is that flapping wing micro-air vehicles are unstable in an open loop setting. The unstable result is based on linear and nonlinear stability analyses. Control has been demonstrated for hovering and forward flight through various methods, both linear and nonlinear in nature. The entirety of reported research into the stability and control of flapping wing micro-air vehicles has neglected the mass effects of the wings on the position and orientation of the central body. Successful control of a flapping wing micro-air vehicle, with the wings' mass effects included, is still an open research area.

  8. Transportation vehicle energy intensities. A joint DOT/NASA reference paper. [energy consumption of air and ground vehicles

    NASA Technical Reports Server (NTRS)

    Mascy, A. C.; Paullin, R. L.

    1974-01-01

    A compilation of data on the energy consumption of air and ground vehicles is presented. The ratio BTU/ASM, British Thermal Units/Available Seat Mile, is used to express vehicle energy intensiveness, and related to the energy consumed directly in producing seat-mile or ton-mile productivity. Data is presented on passenger and freight vehicles which are in current use or which are about to enter service, and advanced vehicles which may be operational in the 1980's and beyond. For the advanced vehicles, an estimate is given of the date of initial operational service, and the performance characteristics. Other key considerations in interpreting energy intensiveness for a given mode are discussed, such as: load factors, operations, overhead energy consumption, and energy investments in new structure and equipment.

  9. Preliminary performance estimates of an oblique, all-wing, remotely piloted vehicle for air-to-air combat

    NASA Technical Reports Server (NTRS)

    Nelms, W. P., Jr.; Bailey, R. O.

    1974-01-01

    A computerized aircraft synthesis program has been used to assess the effects of various vehicle and mission parameters on the performance of an oblique, all-wing, remotely piloted vehicle (RPV) for the highly maneuverable, air-to-air combat role. The study mission consists of an outbound cruise, an acceleration phase, a series of subsonic and supersonic turns, and a return cruise. The results are presented in terms of both the required vehicle weight to accomplish this mission and the combat effectiveness as measured by turning and acceleration capability. This report describes the synthesis program, the mission, the vehicle, and results from sensitivity studies. An optimization process has been used to establish the nominal RPV configuration of the oblique, all-wing concept for the specified mission. In comparison to a previously studied conventional wing-body canard design for the same mission, this oblique, all-wing nominal vehicle is lighter in weight and has higher performance.

  10. Design of composite plastic foams for improved cushioning 

    E-print Network

    Eskew, James Oliver

    1989-01-01

    transmissibility tests. In the following year, the Department of Defense published MIL-HDBK-304A, which established standards in proper cushion design. The report was, and continues to be, a reference to compare various cushioning materials. This military stan... cushioning design is its natural frequency. Every cushioning system has a specific natural frequency, which can be evaluated as part of a transmissibility curve. Comparing transmissibility characteristics for various materials is the best way to judge...

  11. Space robot simulator vehicle

    NASA Technical Reports Server (NTRS)

    Cannon, R. H., Jr.; Alexander, H.

    1985-01-01

    A Space Robot Simulator Vehicle (SRSV) was constructed to model a free-flying robot capable of doing construction, manipulation and repair work in space. The SRSV is intended as a test bed for development of dynamic and static control methods for space robots. The vehicle is built around a two-foot-diameter air-cushion vehicle that carries batteries, power supplies, gas tanks, computer, reaction jets and radio equipment. It is fitted with one or two two-link manipulators, which may be of many possible designs, including flexible-link versions. Both the vehicle body and its first arm are nearly complete. Inverse dynamic control of the robot's manipulator has been successfully simulated using equations generated by the dynamic simulation package SDEXACT. In this mode, the position of the manipulator tip is controlled not by fixing the vehicle base through thruster operation, but by controlling the manipulator joint torques to achieve the desired tip motion, while allowing for the free motion of the vehicle base. One of the primary goals is to minimize use of the thrusters in favor of intelligent control of the manipulator. Ways to reduce the computational burden of control are described.

  12. Improved Adaptive-Reinforcement Learning Control for Morphing Unmanned Air Vehicles

    E-print Network

    Valasek, John

    · Active flow control · Distributed propulsion · Electric propulsion, advanced fuel cells, high- efficiency Air Vehicles Bio/Nano Self-Optimizing Aircraft Advanced Concept Evolution #12;Doebbler, Tandale electric motors · Integrated advanced control systems and information technology · Central "nervous system

  13. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Techinical Equipment Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  14. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Clean Lubrication Oil Storage Tank & Enclosure, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  15. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Supply Warehouse, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  16. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Microwave Equipment Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  17. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Electric Substation, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  18. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Emergency Generator Enclosure, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  19. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Techinical Equipment Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  20. Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Civil Engineering Storage Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  1. Design of an adaptive 3-dimensional display enabled by a swarm of autonomous micro air vehicles

    E-print Network

    Mueller, Erich, S.M. Massachusetts Institute of Technology

    2012-01-01

    This thesis is motivated by the concept of a system consisting of a swarm of small, automatically controlled air vehicles, each carrying a colour-controlled light source (payload), capable of executing coordinated maneouvres ...

  2. Assessing the Link between Environmental Concerns and Consumers' Decisions to Use Clean-Air Vehicles

    ERIC Educational Resources Information Center

    Plax, Timothy G.; Kearney, Patricia; Ross, Ted J.; Jolly, J. Christopher

    2008-01-01

    A consulting contract with the California Air Resources Board led to a project examining how California drivers' and fleet managers' perceptions, attitudes, and consumer behavior regarding Clean Vehicle Technologies influenced their own energy choices when it came to purchasing vehicles. The consultants examined archival research, conducted focus…

  3. Coupled Vehicle Design and Network Flow Optimization for Air Transportation Systems

    E-print Network

    de Weck, Olivier L.

    Coupled Vehicle Design and Network Flow Optimization for Air Transportation Systems Christine: 10.2514/1.27320 Traditionally, the design of a transportation system has focused on either vehicle for a transportation system, it is advantageous to expand the system boundary during the design process to include

  4. [Impact of heavy-duty diesel vehicles on air quality and control of their emissions].

    PubMed

    Zhou, Lei; Wang, Bo-Guang; Tang, Da-Gang

    2011-08-01

    Through an analysis of the characteristics of diesel vehicle emissions and motor vehicle emissions inventories, this paper examines the impact of heavy-duty diesel vehicles on air quality in China as well as issues related to the control of their emissions. Heavy-duty diesel vehicles emit large amounts of nitrogen oxides and particulate matter. Nitrogen oxides is one of the important precursors for the formation of secondary particles and ozone in the atmosphere, causing regional haze. Diesel particulate matter is a major toxic air pollutant with adverse effect on human health, and in particular, the ultrafine particles in 30-100 nm size range can pose great health risks because of its extremely small sizes. Motor vehicles have become a major source of air pollution in many metropolitan areas and city cluster in China, and among them the heavy-duty diesel vehicles are a dominant contributor of nitrogen oxides and particulate matter emissions. Hence, controlling heavy-duty diesel vehicle emissions should be a key component of an effective air quality management plan, and a number of issues related to heavy-duty diesel vehicle emissions need to be addressed. PMID:22619934

  5. Significant Fuel Savings and Emission Reductions by Improving Vehicle Air Conditioning

    Microsoft Academic Search

    John P. Rugh; Valerie Hovland; Stephen O. Andersen

    Vehicle air conditioning (A\\/C) systems significantly increase the fuel use and tailpipe emissions of automobiles. In addition, emissions of the A\\/C refrigerant are greenhouse gases. In 2002, the National Renewable Energy Laboratory (NREL) determined the U.S. national and state-by-state fuel use impact of air conditioning in light duty vehicles. In 2003, we expanded the analysis to cover Europe and Japan.

  6. Fuel Used for Vehicle Air Conditioning: A State-by-State Thermal Comfort-Based Approach

    Microsoft Academic Search

    Valerie H. Johnson

    How much fuel does vehicle air conditioning actually use? This study attempts to answer that question to determine the national and state-by-state fuel use impact seen by using air conditioning in light duty gasoline vehicles. The study used data from US cities, representative of averages over the past 30 years, 1X—see Definitions, the Toyota Prius, the Honda Insight, a 3X

  7. Unmanned air vehicle (UAV) ultra-persitence research

    SciTech Connect

    Dron, S. B.

    2012-03-01

    Sandia National Laboratories and Northrop Grumman Corporation Integrated Systems, Unmanned Systems (NGIS UMS) collaborated to further ultra-persistence technologies for unmanned air vehicles (UAVs). The greatest shortfalls in UAV capabilities have been repeatedly identified as (1) insufficient flight persistence or 'hang time,' (2) marginal electrical power for running higher power avionics and payload systems, and (3) inadequate communications bandwidth and reach. NGIS UMS requested support from Sandia to develop an ultra-persistent propulsion and power system (UP3S) for potential incorporation into next generation UAV systems. The team members tried to determine which energy storage and power generation concepts could most effectively push UAV propulsion and electrical power capabilities to increase UAV sortie duration from days to months while increasing available electrical power at least two-fold. Primary research and development areas that were pursued included these goals: perform general system engineering and integration analyses; develop initial thermal and electrical power estimates; provide mass, volume, dimensional, and balance estimates; conduct preliminary safety assessments; assess logistics support requirements; perform, preliminary assessments of any security and safeguards; evaluate options for removal, replacement, and disposition of materials; generally advance the potential of the UP3S concept. The effort contrasted and compared eight heat sources technologies, three power conversion, two dual cycle propulsion system configurations, and a single electrical power generation scheme. Overall performance, specific power parameters, technical complexities, security, safety, and other operational features were successfully investigated. Large and medium sized UAV systems were envisioned and operational flight profiles were developed for each concept. Heat source creation and support challenges for domestic and expeditionary operations were considered. Fundamental cost driver analysis was also performed. System development plans were drafted in order to determine where the technological and programmatic critical paths lay. As a result of this effort, UAVs were to be able to provide far more surveillance time and intelligence information per mission while reducing the high cost of support activities. This technology was intended to create unmatched global capabilities to observe and preempt terrorist and weapon of mass destruction (WMD) activities. Various DOE laboratory and contractor personnel and facilities could have been used to perform detailed engineering, fabrication, assembly and test operations including follow-on operational support. Unfortunately, none of the results will be used in the near-term or mid-term future. NGIS UMS and SNL felt that the technical goals for the project were accomplished. NGIS UMS was quite pleased with the results of analysis and design although it was disappointing to all that the political realities would not allow use of the results. Technology and system designs evaluated under this CRADA had previously never been applied to unmanned air vehicles (UAVs). Based upon logistic support cost predictions, because the UAVs would not have had to refuel as often, forward basing support costs could have been reduced due to a decrease in the number and extent of support systems and personnel being required to operate UAVs in remote areas. Basic application of the advanced propulsion and power approach is well understood and industry now understands the technical, safety, and political issues surrounding implementation of these strategies. However, the overall economic impact was not investigated. The results will not be applied/implemented. No near-term benefit to industry or the taxpayer will be encountered as a result of these studies.

  8. A Randomized Clinical Trial on Preventing Pressure Ulcers with Wheelchair Seat Cushions

    PubMed Central

    Brienza, David; Kelsey, Sheryl; Karg, Patricia; Allegretti, Ana; Olson, Marian; Schmeler, Mark; Zanca, Jeanne; Geyer, Mary Jo; Kusturiss, Marybeth; Holm, Margo

    2010-01-01

    Objectives To determine the efficacy of skin protection wheelchair seat cushions in preventing pressure ulcers in the elderly, nursing home population Design Clinical trial with participants assigned at random to either a skin protection or segmented foam cushion. Two hundred thirty two participants were recruited between June 2004 and May 2008 and followed for 6 months or until pressure ulcer incidence. Setting Twelve nursing homes Participants Nursing home residents’ age ? 65, using wheelchairs ?6 hours/day, Braden score ? 18, and combined Braden activity and mobility score ? 5. Participants were recruited from a referred sample. Intervention All participants were provided a fitted wheelchair and randomized into skin protection (SPC) or segmented foam (SFC) cushion groups. The SPC group received an air, viscous fluid/foam, or gel/foam cushion. The SFC group received a 7.6 cm crosscut foam cushion. Measurements Pressure ulcer incidence over 6 months for wounds near the ischial tuberosities (IT ulcers) were measured. Secondary analysis was performed on combined IT and sacral/coccyx ulcers. Results One hundred eighty participants reached a study endpoint and 42 were lost to follow-up. Ten did not receive the intervention. There were 8/119 (6.7%) IT ulcers in the SFC group and 1/113 (0.9%) in the SPC group (p<0.04). In the group of combined IT and sacral/coccyx ulcers, there were 21/119 pressure ulcers (17.6%) in the SFC group and 12/113 (10.6%) in the SPC group (p=0.14). Conclusion Skin protection cushions used with fitted wheelchairs lower pressure ulcer incidence for elderly, nursing home residents and should be used to help prevent pressure ulcers. PMID:21070197

  9. Seat cushion comparison for nursing home wheelchair users.

    PubMed

    Shaw, C G

    1993-01-01

    Finding solutions to the seating problems of nursing home wheelchair users is challenging due to the lack of data regarding the pressure-relieving and comfort performance of wheelchair cushions for this population. This study's goal was to determine whether commercially available seat cushions provide better pressure relief and comfort than do traditionally provided or "makeshift" cushions or pads. Using a repeated measures design, 21 nursing home wheelchair users were enlisted to help evaluate two traditionally provided or "makeshift" cushions or pads and two selected commercially available seat cushions. The peak sitting pressures for 20 subjects were recorded using an Oxford pressure monitor. Twenty-one subjects were asked to score the test cushions' comfort. Due to the somewhat surprising results for the traditionally provided eggcrate cushion, the results fell short of supporting our initial hypothesis. Nevertheless, the study did identify three cushions, the eggcrate, the gel/foam, and the foam, which provided significantly lower peak sitting pressure averages than those recorded for the mix of cushions and pads used by 50 residents in a previous survey. Select commercially available seat cushions can offer nursing home residents lower sitting pressures and increased comfort. Further investigation is required to assess the long-term performance of these and other seat cushions and to explore the predictive benefits of the statistically significant relationship identified between peak sitting pressure and comfort. PMID:10146319

  10. Aerodynamic experimentation with ducted models as applied to hypersonic air-breathing vehicles

    Microsoft Academic Search

    Yu. P. Goon'ko

    1999-01-01

    A methodology of experimentation in high supersonic wind tunnels for studying aerodynamic characteristics of hypersonic flying vehicles powered by air-breathing engines is discussed. Investigations of such total aerodynamic forces as drag, lift and pitching moment at testing the models are implicit when the air flow through the model ducts is accomplished so that to provide the simulation of the external

  11. A method for reducing exhaust pressure of vehicle compressed air powered engine

    Microsoft Academic Search

    Zhenggang Xu; Xiaopeng Xie

    2009-01-01

    Compressed air powered engine is a type of zero-pollution engine, but its conversion efficiency is very low for its high pressure exhaust which causes much exergy loss. In this study, a control system was developed to reduce the exhaust pressure of vehicle compressed air powered engine. The control system is made up of a controller, a pressure sensor, a photoelectric

  12. Air quality impacts of motor vehicle emissions in the south coast air basin: Current versus more stringent control scenario

    NASA Astrophysics Data System (ADS)

    Collet, Susan; Kidokoro, Toru; Sonoda, Yukihiro; Lohman, Kristen; Karamchandani, Prakash; Chen, Shu-Yun; Minoura, Hiroaki

    2012-02-01

    States are working to comply with the ozone National Ambient Air Quality Standards (NAAQS). Often, regulations restricting vehicle emissions are promulgated in order to attain compliance with the NAAQS. Currently, more stringent vehicle emission regulations are being considered by government agencies. This paper compares emissions from passenger cars and light duty trucks under the current California Low Emission Vehicle (LEV II) standards to a control scenario which was anticipated in 2008 to become LEV III (referred to as "more stringent control" in this paper) and determines if the scenario would result in additional improvements to air quality in California's South Coast Air Basin. The air quality modeling was performed using the Community Multi-scale Air Quality Model (CMAQ) for years 2005, 2014 and 2020. The more stringent control sensitivity study simulated a scenario in which all new passenger cars and light duty trucks in the California South Coast Air Basin in year 2016 achieve Super Ultra-Low Emission Vehicle (SULEV) tail pipe emissions, zero evaporative emissions and more stringent aggressive driving requirements. The total on-road vehicles emissions difference when averaged across the South Coast Air Basin showed the more stringent scenario compared to LEV II to have reductions of 1% for oxides of nitrogen (NO x), 1% for as reactive organic gases (ROG) and 5% for carbon monoxide (CO) in 2030. LEV II modeled ozone levels in the western areas of the basin increased in 2014 and 2020 as compared to 2005, because these areas are VOC-sensitive and the reductions in NO x emissions in these regions are larger than the VOC reductions. In other areas of the South Coast Basin, ozone is reduced by 1.5% or less. The more stringent control scenario modeled levels of ozone have a maximum decrease from LEV II levels by 1% or less in 2014 and 1.5% or less in 2020.

  13. Operator state estimation for adaptive aiding in uninhabited combat air vehicles

    NASA Astrophysics Data System (ADS)

    Russell, Christopher A.

    Chris Russell's research, sponsored by the Air Force Research Laboratory Human Effectiveness Directorate, demonstrated significant improvement of mission effectiveness using adaptive automation and the operator's mental workload in Uninhabited Combat Air Vehicle (UCAV) missions. His work is the first example of closing the loop between the human and the machine by using mental workload based on physiological signals from the operator to adapt the system. Implementation of his research is being demonstrated in a variety of applications, including the Uninhabited Combat Air Vehicle control workstation, Tactical Tomahawk Weapons Control System, and the Objective Force Warrior Program.

  14. Modeling and analysis of an articulated winged micro air vehicle for gust mitigation

    NASA Astrophysics Data System (ADS)

    Oduyela, Adetunji Y.

    Articulated micro air vehicles are a class of micro air vehicles comprised of a main center body attached to outer wings on both sides. As in the case of a single rigid micro air vehicle, the center body and the attached bodies in the articulated case are all responsible for the generation of aerodynamic forces and moments during flight resulting in a multibody system. While many approaches have been taken in the literature to model the system of equations resulting from such a complicated multibody system, this dissertation presents an approach based on a Newton-Euler multibody dynamics formulation where the multiple bodies are attached together with suitable joints. The number and type of joints determines the level of articulation and total degree of freedom for the entire system. Unlike most articulated air vehicle model formulations available in the literature, the final model formulation presented in this work provides joint force and moment data acting on the articulated MAV during flight. This feature allows such information to be available during the vehicle design and development stage where appropriate spring and dampers for the system are selected based on mission requirements. Experimental validation of the proposed mathematical model using experimental flight test data obtained from UAHuntsville's Autonomous Tracking and Optical Measurements laboratory allowed the comparison of the flight test results and model simulations. Analytical investigation of the gust alleviation properties of the articulated 8 degree-of-freedom micro air vehicle model was carried out using simulations with varying crosswind gust magnitudes and shows that the passive articulation in micro air vehicles increases their robustness to gusts when suitable joint parameters are selected.

  15. Fire resistant resilient foams. [for seat cushions

    NASA Technical Reports Server (NTRS)

    Gagliani, J.

    1976-01-01

    Primary program objectives were the formulation, screening, optimization and characterization of open-cell, fire resistant, low-smoke emitting, thermally stable, resilient polyimide foams suitable for seat cushions in commercial aircraft and spacecraft. Secondary program objectives were to obtain maximum improvement of the tension, elongation and tear characteristics of the foams, while maintaining the resiliency, thermal stability, low smoke emission and other desirable attributes of these materials.

  16. Factors affecting static seat cushion comfort.

    PubMed

    Ebe, K; Griffin, M J

    2001-08-15

    To improve the understanding of factors affecting automobile seat cushion comfort in static conditions (i.e. without vibration), relationships between the static physical characteristics of a seat cushion and seat comfort have been investigated. The static seat comfort of four automobile cushions, with the same foam hardness but different foam compositions, was investigated using Scheffe's method of paired comparisons. The comfort judgements were correlated with sample stiffness, given by the gradient of a force-deflection curve at 490 N (= 50 kgf). Samples with lower stiffness were judged to be more comfortable than samples with greater stiffness. A similar comfort evaluation was conducted using five rectangular foam samples of the same composition but different foam hardness (and a wider range than in the first experiment). There was no linear relationship between the sample stiffness and seat comfort for these samples. Static seat cushion comfort seemed to be affected by two factors, a 'bottoming feeling' and a 'foam hardness feeling'. The bottoming feeling was reflected in the sample stiffness when loaded to 490 N, while the foam hardness feeling was reflected in foam characteristics at relatively low forces. The pressures underneath the buttocks of subjects were compared with the comfort judgements. The total pressure over a 4 cm x 4 cm area beneath the ischial bones was correlated with static seat comfort, even when the differences among samples were great; samples with less total pressure in this area were judged to be more comfortable than samples with greater total pressure. It is concluded that the pressure beneath the ischial bones may reflect both comfort factors: the bottoming feeling and the foam hardness feeling. PMID:11681792

  17. Valuation of plug-in vehicle life-cycle air emissions and oil displacement benefits

    PubMed Central

    Michalek, Jeremy J.; Chester, Mikhail; Jaramillo, Paulina; Samaras, Constantine; Shiau, Ching-Shin Norman; Lave, Lester B.

    2011-01-01

    We assess the economic value of life-cycle air emissions and oil consumption from conventional vehicles, hybrid-electric vehicles (HEVs), plug-in hybrid-electric vehicles (PHEVs), and battery electric vehicles in the US. We find that plug-in vehicles may reduce or increase externality costs relative to grid-independent HEVs, depending largely on greenhouse gas and SO2 emissions produced during vehicle charging and battery manufacturing. However, even if future marginal damages from emissions of battery and electricity production drop dramatically, the damage reduction potential of plug-in vehicles remains small compared to ownership cost. As such, to offer a socially efficient approach to emissions and oil consumption reduction, lifetime cost of plug-in vehicles must be competitive with HEVs. Current subsidies intended to encourage sales of plug-in vehicles with large capacity battery packs exceed our externality estimates considerably, and taxes that optimally correct for externality damages would not close the gap in ownership cost. In contrast, HEVs and PHEVs with small battery packs reduce externality damages at low (or no) additional cost over their lifetime. Although large battery packs allow vehicles to travel longer distances using electricity instead of gasoline, large packs are more expensive, heavier, and more emissions intensive to produce, with lower utilization factors, greater charging infrastructure requirements, and life-cycle implications that are more sensitive to uncertain, time-sensitive, and location-specific factors. To reduce air emission and oil dependency impacts from passenger vehicles, strategies to promote adoption of HEVs and PHEVs with small battery packs offer more social benefits per dollar spent. PMID:21949359

  18. Intelligent energy management control of vehicle air conditioning via look-ahead system

    Microsoft Academic Search

    Hamid Khayyam; Saeid Nahavandi; Eric Hu; Abbas Kouzani; Ashley Chonka; Jemal Abawajy; Vincenzo Marano; Sam Davis

    2011-01-01

    Air conditioning systems (A\\/C) significantly increase the energy consumption of a vehicle and negatively influence its performance. A\\/C can be considered the main auxiliary load on a vehicle engine when it is operating. Thus, there are significant savings to be made by operating an A\\/C system smartly, both in terms of running costs and the effect on the environment. This

  19. Adaptive Neuro-Fuzzy Inference System Based Autonomous Flight Control of Unmanned Air Vehicles

    Microsoft Academic Search

    Sefer Kurnaz; Okyay Kaynak; Ekrem Konakoglu

    2007-01-01

    This paper proposes ANFIS logic based autonomous flight controller for UAVs (unmanned aerial vehicles). Three fuzzy logic\\u000a modules are developed for the control of the altitude, the speed, and the roll angle, through which the altitude and the latitude-longitude\\u000a of the air vehicle is controlled. The implementation framework utilizes MATLAB’s standard configuration and the Aerosim Aeronautical\\u000a Simulation Block Set which

  20. Combatting urban air pollution through Natural Gas Vehicle (NGV) analysis, testing, and demonstration

    SciTech Connect

    NONE

    1995-03-01

    Deteriorating urban air quality ranks as a top concern worldwide, since air pollution adversely affects both public health and the environment. The outlook for improving air quality in the world`s megacities need not be bleak, however, The use of natural gas as a transportation fuel can measurably reduce urban pollution levels, mitigating chronic threats to health and the environment. Besides being clean burning, natural gas vehicles (NGVs) are economical to operate and maintain. The current cost of natural gas is lower than that of gasoline. Natural gas also reduces the vehicle`s engine wear and noise level, extends engine life, and decreases engine maintenance. Today, about 700,000 NGVs operate worldwide, the majority of them converted from gasoline or diesel fuel. This article discusses the economic, regulatory and technological issues of concern to the NGV industry.

  1. Low-Observable Nonlinear Trajectory Generation for Unmanned Air Vehicles

    E-print Network

    Murray, Richard M.

    and turning rate limits, while avoiding threats and collisions with other vehicles. Driven by battlespace optimization problems, and it presents new challenges for This research is based upon work supported Keywords: Trajectory Generation, Path Planning, Low-Observable, UAV, RADAR, Probability of Detection

  2. A diagnostic system for air brakes in commercial vehicles 

    E-print Network

    Coimbatore Subramanian, Shankar Ram

    2007-09-17

    to maintenance and hence they require frequent inspections. Current inspection techniques require an inspector to go underneath a vehicle to check the brake system for possible faults, such as leaks, worn brake pads, out-of-adjustment of push rods, etc...

  3. Study of long term options for electric vehicle air conditioning

    Microsoft Academic Search

    J. Dieckmann; D. Mallory

    1991-01-01

    There are strong incentives in terms of national energy and environmental policy to encourage the commercialization of electrically powered vehicles in the U.S. Among these incentives are reduced petroleum consumption, improved electric generation capacity utilization, reduced IC engine emissions, and, depending on the primary fuel used for electric power generation, reduced emissions of carbon dioxide. A basic requirement for successfully

  4. Air actuated clutch for four wheel drive vehicles

    SciTech Connect

    Clohessy, K.E.

    1986-12-09

    A control system is described for selectively engaging and disengaging a vehicle wheel and a vehicle drive mechanism comprising; a spindle having inside and outside rotative support surfaces, the spindle adapted to be mounted to a vehicle frame, an axle portion rotatably supported on the inside support surface, and drive means for selectively and rotatively driving the axle portion relative to the spindle; a wheel hub assembly adapted to carry a vehicle wheel, the hub assembly rotatively supported on the outside support surface of the spindle; a sealed expansion chamber defined in part by the spindle, the axle portion, the hub assembly and a movable wall carried by the hub assembly, venting means venting the outer side of the movable wall to atmospheric pressure, the clutch ring engaged by the movable wall for movement of the clutch ring with movement of the movable wall as induced by a pressure difference generated within the chamber, and pressurizing means for selectively pressurizing and depressurizing the expansion chamber to thereby selectively shift the clutch ring between the positions of interlocking the axle portion and hub assembly and unlocking the axle portion and hub assembly.

  5. 24 CFR 200.948 - Building product standards and certification program for carpet cushion.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...standards and certification program for carpet cushion. 200.948 Section 200.948...standards and certification program for carpet cushion. (a) Applicable standards. (1) All carpet cushion shall be designed,...

  6. Analysis and optimization of an adsorption air conditioner for electric vehicle applications

    SciTech Connect

    Aceves, S.M.

    1994-07-27

    This paper shows an analysis of the applicability of an adsorption system for electric vehicle (EV) air conditioning. Adsorption systems are designed and optimized to provide the required cooling for four combinations of vehicle characteristics and driving cycles. The resulting adsorption systems are compared with vapor compression air conditioners that can satisfy the cooling load. The objective function is the overall system weight, which includes the cooling system weight and the weight of the battery necessary to provide energy for air conditioner operation. The system with the minimum overall weight is considered to be the best. The results show the optimum values of all the variables, as well as temperatures and amounts adsorbed, for the adsorption and desorption processes. The results indicate that, for the conditions analyzed in this paper, vapor compression air conditioners are superior to adsorption systems, not only because they are lighter, but also because they have a higher COP and are more compact.

  7. Propulsion integration of hypersonic air-breathing vehicles utilizing a top-down design methodology

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, Brad Kenneth

    In recent years, a focus of aerospace engineering design has been the development of advanced design methodologies and frameworks to account for increasingly complex and integrated vehicles. Techniques such as parametric modeling, global vehicle analyses, and interdisciplinary data sharing have been employed in an attempt to improve the design process. The purpose of this study is to introduce a new approach to integrated vehicle design known as the top-down design methodology. In the top-down design methodology, the main idea is to relate design changes on the vehicle system and sub-system level to a set of over-arching performance and customer requirements. Rather than focusing on the performance of an individual system, the system is analyzed in terms of the net effect it has on the overall vehicle and other vehicle systems. This detailed level of analysis can only be accomplished through the use of high fidelity computational tools such as Computational Fluid Dynamics (CFD) or Finite Element Analysis (FEA). The utility of the top-down design methodology is investigated through its application to the conceptual and preliminary design of a long-range hypersonic air-breathing vehicle for a hypothetical next generation hypersonic vehicle (NHRV) program. System-level design is demonstrated through the development of the nozzle section of the propulsion system. From this demonstration of the methodology, conclusions are made about the benefits, drawbacks, and cost of using the methodology.

  8. Aerodynamic experimentation with ducted models as applied to hypersonic air-breathing vehicles

    Microsoft Academic Search

    Yu. P. Goon’ko

    1999-01-01

    A methodology of experimentation in high supersonic wind tunnels for studying aerodynamic characteristics of hypersonic flying\\u000a vehicles powered by air-breathing engines is discussed. Investigations of such total aerodynamic forces as drag, lift and\\u000a pitching moment at testing the models are implicit when the air flow through the model ducts is accomplished so that to provide\\u000a the simulation of the external

  9. Design and analysis of aluminum\\/air battery system for electric vehicles

    Microsoft Academic Search

    Shaohua Yang; Harold Knickle

    2002-01-01

    Aluminum (Al)\\/air batteries have the potential to be used to produce power to operate cars and other vehicles. These batteries might be important on a long-term interim basis as the world passes through the transition from gasoline cars to hydrogen fuel cell cars. The Al\\/air battery system can generate enough energy and power for driving ranges and acceleration similar to

  10. Assessment of adsorber bed designs in waste-heat driven adsorption cooling systems for vehicle air conditioning and refrigeration

    E-print Network

    Bahrami, Majid

    ) for vehicle air conditioning and refrigeration (A/C­R) applications. Adsorber beds should be specifically conditioning and refrigeration Amir Sharafian, Majid Bahrami n Laboratory for Alternative Energy ConversionAssessment of adsorber bed designs in waste-heat driven adsorption cooling systems for vehicle air

  11. Development of Micro Air Reconnaissance Vehicle as a Test Bed for Advanced Sensors and Electronics

    NASA Technical Reports Server (NTRS)

    Shams, Qamar A.; Vranas, Thomas L.; Fox, Robert L.; Kuhn, Theodore R.; Ingham, John; Logan, Michael J.; Barnes, Kevin N.; Guenther, Benjamin F.

    2002-01-01

    This paper describes the development of a Micro/Mini Air Reconnaissance Vehicle for advanced sensors and electronics at NASA Langley Research Center over the last year. This vehicle is expected to have a total weight of less than four pounds, a design velocity of 40 mph, an endurance of 15-20 minutes, and a maximum range of 5km. The vehicle has wings that are simple to detach yet retain the correct alignment. The upper fuselage surface has a quick release hatch used to access the interior and also to mount the varying propulsion systems. The sensor suite developed for this vehicle consists of a Pitot-static measurement system for determining air speed, an absolute pressure measurement for determining altitude, magnetic direction measurement, and three orthogonal gyros to determine body angular rates. Swarming GPS-guidance and in-flight maneuvering is discussed, as well as design and installation of some other advance sensors like MEMS microphones, infrared cameras, GPS, humidity sensors, and an ultrasonic sonar sensor. Also low cost, small size, high performance control and navigation system for the Micro Air Vehicle is discussed. At the end, laboratory characterization of different sensors, motors, propellers, and batteries will be discussed.

  12. Intake fraction of primary pollutants: motor vehicle emissions in the South Coast Air Basin

    NASA Astrophysics Data System (ADS)

    Marshall, Julian D.; Riley, William J.; McKone, Thomas E.; Nazaroff, William W.

    The intake fraction is defined for a specific species and emission source as the ratio of attributable population intake to total emissions. Focusing on California's South Coast Air Basin (SoCAB) as a case study, we combine ambient monitoring data with time-activity patterns to estimate the population intake of carbon monoxide and benzene emitted from motor vehicles during 1996-1999. In addition to exposures to ambient concentrations, three microenvironments are considered in which the exposure concentration of motor vehicle emissions is higher than in ambient air: in and near vehicles, inside a building that is near a freeway, and inside a residence with an attached garage. Incorporating data on motor vehicle emissions estimated by the EMFAC2000 model, we estimate that the 15 million people in the SoCAB inhale 0.003-0.009% (34-85 per million, with a best estimate of 47 per million) of primary, nonreactive compounds emitted into the basin by motor vehicles. This population intake of primary motor vehicle emissions is approximately 50% higher than the average ambient concentration times the average breathing rate, owing to higher concentrations in the three microenvironments and also to the temporal and spatial correlation among breathing rates, concentrations, and population densities. The approach demonstrated here can inform policy decisions requiring a metric of population exposure to airborne pollutants.

  13. Image Multiresolution Discriminant Analysis for Vision-Guided Stability of Micro Air Vehicles

    Microsoft Academic Search

    Sinisa Todorovic; Michael C. Nechyba; Antonio A. Arroyo

    Recently, we have successfully implemented and tested a vision based horizon-tracking algorithm for flight stability and autonomy in Micro Air Vehicles (MAVs). Occa- sionally, this algorithm fails in scenarios where the underlying Gaussian assumption for the sky and ground appearances is not appropriate. To improve its performance, especially in the presence of video noise, we consider a novel image analy-

  14. Robust Gain Scheduling Control of Air-breathing Hypersonic Vehicle via Linear Parameter Varying Technique

    Microsoft Academic Search

    Cunkan Lu; Dudu Zhong; Weiwei Yu; Jie Yan

    2008-01-01

    The design of a robust gain scheduling controller which is scheduled on Mach number and altitude for the air-breathing hypersonic vehicle (AHV) is presented. In order to capture the nonlinear airspeed and altitude dependence of AHV, a linear parameter varying (LPV) model is constructed from a set of linearization of the AHV longitudinal dynamics. The linear fractional transformation (LFT) representation

  15. A 1-gram dual sensorless speed governor for micro-air vehicles

    Microsoft Academic Search

    S. Viollet; L. Kerhuel; N. Franceschini

    2008-01-01

    Embedding electronic control circuits onboard micro-air vehicles (MAVs) is a challenge in view of the stringent limitations in terms of mass, size, and power consumption. The propulsion unit is a cornerstone in the design of a MAV. In this study, we introduce a 'sensorless' speed governor (regulator) for a propulsion unit composed of a miniature propeller (diameter 12 cm), a

  16. Rehabilitation of the Rocket Vehicle Integration Test Stand at Edwards Air Force Base

    NASA Technical Reports Server (NTRS)

    Jones, Daniel S.; Ray, Ronald J.; Phillips, Paul

    2005-01-01

    Since initial use in 1958 for the X-15 rocket-powered research airplane, the Rocket Engine Test Facility has proven essential for testing and servicing rocket-powered vehicles at Edwards Air Force Base. For almost two decades, several successful flight-test programs utilized the capability of this facility. The Department of Defense has recently demonstrated a renewed interest in propulsion technology development with the establishment of the National Aerospace Initiative. More recently, the National Aeronautics and Space Administration is undergoing a transformation to realign the organization, focusing on the Vision for Space Exploration. These initiatives provide a clear indication that a very capable ground-test stand at Edwards Air Force Base will be beneficial to support the testing of future access-to-space vehicles. To meet the demand of full integration testing of rocket-powered vehicles, the NASA Dryden Flight Research Center, the Air Force Flight Test Center, and the Air Force Research Laboratory have combined their resources in an effort to restore and upgrade the original X-15 Rocket Engine Test Facility to become the new Rocket Vehicle Integration Test Stand. This report describes the history of the X-15 Rocket Engine Test Facility, discusses the current status of the facility, and summarizes recent efforts to rehabilitate the facility to support potential access-to-space flight-test programs. A summary of the capabilities of the facility is presented and other important issues are discussed.

  17. NEURAL NETS AND OPTIC FLOW FOR AUTONOMOUS MICRO-AIR-VEHICLE and William E. Green

    E-print Network

    Oh, Paul

    USING OPTIC FLOW Insects make heavy use of vision, especially optic flow, for perceiving the environmentNEURAL NETS AND OPTIC FLOW FOR AUTONOMOUS MICRO-AIR-VEHICLE NAVIGATION Paul Y. Oh and William E in complex environ- ments. Our demonstrations with optic flow microsensors have been promising but controller

  18. Air data sensors for atmospheric reentry flight test of winged space vehicle

    Microsoft Academic Search

    Yoshifumi Inatani; Koichi Yonemoto

    1992-01-01

    The first atmospheric reentry flight of a winged space vehicle in Japan was conducted and an Air Data Sensor (ADS) System was developed for the flight test. ADS was designed to measure flight angle-of-attack and sideslip associated with the flight Mach number. These outputs from ADS were used for the flight control loop in real time, where the Mach number

  19. Fault-tolerant output tracking control for a flexible air-breathing hypersonic vehicle

    Microsoft Academic Search

    Hongyi Li; Yulin Si; Ligang Wu; Xiaoxiang Hu; Zeguo Wang; Huijun Gao

    2010-01-01

    This paper addresses the problem of guaranteed cost fault-tolerant output tracking control against actuator faults for a flexible air-breathing hypersonic vehicle. Firstly, using the parameters of the trim condition, a linearized model is established around the trim point for a nonlinear, dynamically coupled simulation model. Secondly, the control objective and models of actuator faults are presented. Thirdly, the performance analysis

  20. Robust linear parameter-varying control of air-breathing hypersonic vehicle considering input constraints

    Microsoft Academic Search

    Dong Ming Ge; Xian Lin. Huang

    2010-01-01

    For an air-breathing hypersonic vehicle model subject to input constraints, this paper is concerned with the application of linear control theory to design its flight control system. In the framework of integral quadratic constraints (IQCs), the standard linear parameter-varying (LPV) control method is generalized to deal with the parametric, dynamic uncertainties and saturation nonlinearities associated with the model. Based on

  1. Australian Air Breathing Propulsion Research for Hypersonic, Beamed Energy-Propelled Vehicles

    Microsoft Academic Search

    David Froning

    2010-01-01

    A three year laser-propelled vehicle analysis and design investigation has been begun in June, 2009 by Faculty and graduate students at the University of Adelaide under a Grant\\/Cooperative Agreement Award to the University of Adelaide by the Asian Office of Aerospace Research and Development (AOARD). The major objectives of thsis investigation are: (a) development of hypersonic, air breathing ``lightcraft'' with

  2. Landing an Unmanned Air Vehicle: Vision Based Motion Estimation and Nonlinear Control

    Microsoft Academic Search

    Omid Shakernia; Yi Ma; T. John; Koo Shankar Sastry

    1999-01-01

    In this paper, we use computer vision as a feedback sensor in a control loop for landing an unmanned air vehicle (UAV) on a landing pad. The vision problem we address here is then a special case of the classic ego-motion estimation problem since all feature points lie on a planar surface (the landing pad). We study together the discrete

  3. Parametric control of multiple unmanned air vehicles over an unknown hostile territory

    Microsoft Academic Search

    K. Madhava Krishna; Henry Hexmoor; Subbarao Pasupuleti; James Llinas

    2005-01-01

    A methodology for real-time control of unmanned air vehicles (UAV) in the absence of a -priori knowledge of hostile territory is presented. The control methodology generates a sequence of waypoints to be pursued by the UV until the goal is reached. The controller computes the waypoints every time new information is obtained regarding the presence or absence of a hostile

  4. A vision system for intelligent mission profiles of micro air vehicles

    Microsoft Academic Search

    Sinisa Todorovic; Michael C. Nechyba

    2004-01-01

    Recently, much progress has been made toward the development of small-scale aircraft, known broadly as Micro Air Vehicles (MAVs). Until recently, these platforms were exclusively remotely piloted, with no autonomous or intelligent capabilities, due at least in part to stringent payload restrictions that limit onboard sensors. However, the one sensor that is critical to most conceivable MAV missions, such as

  5. Parametric Control of Multiple Unmanned Air Vehicles over an Unknown Hostile Territory

    E-print Network

    Hexmoor, Henry

    @eng.buffalo.edu Abstract-- A methodology for real-time control of unmanned air vehicles (UAV) in the absence of a on the ground and the danger of UAV grounded as a result of its prolonged stay over the hostile territory. The multi-agency in the system is due to the broadcast of newly observed information by an UAV to its

  6. Trajectory tracking for unmanned air vehicles with velocity and heading rate constraints

    Microsoft Academic Search

    Wei Ren; Randal W. Beard

    2004-01-01

    This paper considers the problem of constrained nonlinear trajectory tracking control for unmanned air vehicles (UAVs). We assume that the UAV is equipped with longitudinal and lateral autopilots which reduces the 12-state model to a six-state model with altitude, heading, and velocity command inputs. One of the novel features of our approach is that we explicitly account for heading rate

  7. Challenges for micro-scale flapping-wing micro air vehicles

    NASA Astrophysics Data System (ADS)

    Wood, Robert J.; Finio, Benjamin; Karpelson, Michael; Pérez-Arancibia, Nestor O.; Sreetharan, Pratheev; Whitney, John P.

    2012-06-01

    The challenges for successful flight of insect-scale micro air vehicles encompass basic questions of fabrication, design, propulsion, actuation, control, and power - topics that have in general been answered for larger aircraft. When developing a flying robot on the scale of flies and bees, all hardware must be developed from scratch as there are no "off-the-shelf" sensors, actuators, or microcontrollers that can satisfy the extreme mass and power limitations imposed by such vehicles. Similar challenges exist for fabrication and assembly of the structural and aeromechanical components of insect-scale micro air vehicles that neither macro-scale techniques nor MEMS can adequately solve. With these challenges in mind, this paper presents progress in the essential technologies for micro-scale flapping-wing robots.

  8. Structural characteristics via SLDV for a class of morphing micro-air-vehicles

    NASA Astrophysics Data System (ADS)

    Diggs, Edward C.; Bilgen, Onur; Kurdila, Andrew; Kochersburger, Kevin; Inman, Dan; Vignola, Joe

    2007-04-01

    Conventional control surfaces have been used in most carbon fiber composite, membrane-wing autonomous micro air vehicles (MAV). In some cases, vehicle morphing is achieved using servo actuators to articulate vehicle kinematic joints, or to deform crucial wing / tail surfaces. However, articulated lifting surfaces and articulated wing sections are difficult to instrument and fabricate in a repeatable fashion. Assembly is complex and time consuming. The goal of this paper is to establish the feasibility of morphing wings on autonomous MAVs that are actuated via active materials. Active actuation is achieved via a type of piezoceramic composite called Macro Fiber Composite (MFC). This paper investigates the structural dynamics of morphing wings on MAVs that are actuated via active composites. This paper continues the work presented in1 by considering structural dynamic characteristics of the morphing vehicle determined through Scanning Laser Doppler Vibrometry (SLDV).

  9. Space Shuttle Solid Rocket Booster decelerator subsystem - Air drop test vehicle/B-52 design

    NASA Technical Reports Server (NTRS)

    Runkle, R. E.; Drobnik, R. F.

    1979-01-01

    The air drop development test program for the Space Shuttle Solid Rocket Booster Recovery System required the design of a large drop test vehicle that would meet all the stringent requirements placed on it by structural loads, safety considerations, flight recovery system interfaces, and sequence. The drop test vehicle had to have the capability to test the drogue and the three main parachutes both separately and in the total flight deployment sequence and still be low-cost to fit in a low-budget development program. The design to test large ribbon parachutes to loads of 300,000 pounds required the detailed investigation and integration of several parameters such as carrier aircraft mechanical interface, drop test vehicle ground transportability, impact point ground penetration, salvageability, drop test vehicle intelligence, flight design hardware interfaces, and packaging fidelity.

  10. Effect of vehicle type on the performance of second generation air bags for child occupants.

    PubMed

    Arbogast, Kristy B; Durbin, Dennis R; Kallan, Michael J; Winston, Flaura K

    2003-01-01

    Passenger air bags experienced considerable design modification in the late 1990s, principally to mitigate risks to child passengers. This study utilized Data from the Partners for Child Passenger Safety study, a large-scale child-focused crash surveillance system, to examine the effect of vehicle type on the differential performance of first and second generation air bags on injuries to restrained children in frontal impact crashes. Our results show that the benefit of second-generation air bags was seen in passenger cars - those children exposed to second-generation air bags were half as likely to sustain a serious injury - and minivans. However, in SUVs the data suggest no reduction in injury risk with the new designs. This field data provides crucial real-world experience to the automotive industry as they work towards the next generation of air bag designs. PMID:12941218

  11. Performance Validation Approach for the GTX Air-Breathing Launch Vehicle

    NASA Technical Reports Server (NTRS)

    Trefny, Charles J.; Roche, Joseph M.

    2002-01-01

    The primary objective of the GTX effort is to determine whether or not air-breathing propulsion can enable a launch vehicle to achieve orbit in a single stage. Structural weight, vehicle aerodynamics, and propulsion performance must be accurately known over the entire flight trajectory in order to make a credible assessment. Structural, aerodynamic, and propulsion parameters are strongly interdependent, which necessitates a system approach to design, evaluation, and optimization of a single-stage-to-orbit concept. The GTX reference vehicle serves this purpose, by allowing design, development, and validation of components and subsystems in a system context. The reference vehicle configuration (including propulsion) was carefully chosen so as to provide high potential for structural and volumetric efficiency, and to allow the high specific impulse of air-breathing propulsion cycles to be exploited. Minor evolution of the configuration has occurred as analytical and experimental results have become available. With this development process comes increasing validation of the weight and performance levels used in system performance determination. This paper presents an overview of the GTX reference vehicle and the approach to its performance validation. Subscale test rigs and numerical studies used to develop and validate component performance levels and unit structural weights are outlined. The sensitivity of the equivalent, effective specific impulse to key propulsion component efficiencies is presented. The role of flight demonstration in development and validation is discussed.

  12. An Air-Launched Low-Cost Launch Vehicle

    NASA Astrophysics Data System (ADS)

    Hudson, Gary C.

    2005-02-01

    The QuickReach concept is a responsive, mobile, air-launched, two-stage liquid pressure-fed rocket that is capable of placing nearly 2,000 pounds into low earth orbit. The rocket is extracted from a transport aircraft using gravity and a small drogue parachute for orientation stabilization. The design of the container holding the rocket allows the use of existing transport aircraft without any modification. Propulsion is LOX and propane using the Vapak concept for tank pressurization. Structures make use of advanced composites.

  13. Impact of aeroelasticity on propulsion and longitudinal flight dynamics of an air-breathing hypersonic vehicle

    NASA Technical Reports Server (NTRS)

    Raney, David L.; Mcminn, John D.; Pototzky, Anthony S.; Wooley, Christine L.

    1993-01-01

    Many air-breathing hypersonic aerospacecraft design concepts incorporate an elongated fuselage forebody acting as the aerodynamic compression surface for a hypersonic combustion module, or scram jet. This highly integrated design approach creates the potential for an unprecedented form of aero-propulsive-elastic interaction in which deflections of the vehicle fuselage give rise to propulsion transients, producing force and moment variations that may adversely impact the rigid body flight dynamics and/or further excite the fuselage bending modes. To investigate the potential for such interactions, a math model was developed which included the longitudinal flight dynamics, propulsion system, and first seven elastic modes of a hypersonic air-breathing vehicle. Perturbation time histories from a simulation incorporating this math model are presented that quantify the propulsive force and moment variations resulting from aeroelastic vehicle deflections. Root locus plots are presented to illustrate the effect of feeding the propulsive perturbations back into the aeroelastic model. A concluding section summarizes the implications of the observed effects for highly integrated hypersonic air-breathing vehicle concepts.

  14. Evaluation of some deceleration--time pulse shapes for possible incorporation into roadside crash cushion design

    E-print Network

    Carpenter, Marvin Ernest

    1972-01-01

    in high initial pulses 37 12 ~ Differences in early pulses 39 13. 8est and worst vehicle pulses 42 CHAPTER I I N TR0 DU CT 10 N In the past, many people have been killed or badly injured when their automobile went out of control and smashed into some... under typical automobile-to-crash cushion impact conditions to get this minimum occupant injury hazard. That is, the optimum automobile deceleration-time history (or "deceleration pulse" shape) for this situation is not known. And, until...

  15. Determining air quality and greenhouse gas impacts of hydrogen infrastructure and fuel cell vehicles.

    PubMed

    Stephens-Romero, Shane; Carreras-Sospedra, Marc; Brouwer, Jacob; Dabdub, Donald; Samuelsen, Scott

    2009-12-01

    Adoption of hydrogen infrastructure and hydrogen fuel cell vehicles (HFCVs) to replace gasoline internal combustion engine (ICE) vehicles has been proposed as a strategy to reduce criteria pollutant and greenhouse gas (GHG) emissions from the transportation sector and transition to fuel independence. However, it is uncertain (1) to what degree the reduction in criteria pollutants will impact urban air quality, and (2) how the reductions in pollutant emissions and concomitant urban air quality impacts compare to ultralow emission gasoline-powered vehicles projected for a future year (e.g., 2060). To address these questions, the present study introduces a "spatially and temporally resolved energy and environment tool" (STREET) to characterize the pollutant and GHG emissions associated with a comprehensive hydrogen supply infrastructure and HFCVs at a high level of geographic and temporal resolution. To demonstrate the utility of STREET, two spatially and temporally resolved scenarios for hydrogen infrastructure are evaluated in a prototypical urban airshed (the South Coast Air Basin of California) using geographic information systems (GIS) data. The well-to-wheels (WTW) GHG emissions are quantified and the air quality is established using a detailed atmospheric chemistry and transport model followed by a comparison to a future gasoline scenario comprised of advanced ICE vehicles. One hydrogen scenario includes more renewable primary energy sources for hydrogen generation and the other includes more fossil fuel sources. The two scenarios encompass a variety of hydrogen generation, distribution, and fueling strategies. GHG emissions reductions range from 61 to 68% for both hydrogen scenarios in parallel with substantial improvements in urban air quality (e.g., reductions of 10 ppb in peak 8-h-averaged ozone and 6 mug/m(3) in 24-h-averaged particulate matter concentrations, particularly in regions of the airshed where concentrations are highest for the gasoline scenario). PMID:19943683

  16. ENSC 461 PROJECT: Next generation air conditioning systems for vehicles Assigned date: Feb. 21, 2011 Due date: April 11, 2011

    E-print Network

    Bahrami, Majid

    air conditioning systems used in the automotive industry are based on vapour-compression refrigeration1 ENSC 461 PROJECT: Next generation air conditioning systems for vehicles Assigned date: Feb. 21, 2011 Due date: April 11, 2011 Introduction Air conditioning is a critical system for hybrid electronic

  17. Concentrations of air toxics in motor vehicle-dominated environments.

    PubMed

    Fujita, Eric M; Campbell, David E; Zielinska, Barbara; Arnott, William P; Chow, Judith C

    2011-02-01

    We at the Desert Research Institute (DRI*) measured volatile organic compounds (VOCs), including several mobile-source air toxics (MSATs), particulate matter with a mass mean aerodynamic diameter < or = 2.5 pm (PM2.5), black carbon (BC), nitrogen oxides (NOx), particulate matter (PM), and carbon monoxide (CO) on highways in Los Angeles County during summer and fall 2004, to characterize the diurnal and seasonal variations in measured concentrations related to volume and mix of traffic. Concentrations of on-road pollutants were then compared to corresponding measurements at fixed monitoring sites. The on-road concentrations of CO and MSATs were higher in the morning under stable atmospheric conditions and during periods of higher traffic volumes. In contrast, BC concentrations, measured as particulate light absorption, were higher on truck routes during the midday sampling periods despite more unstable atmospheric conditions. Compared to the measurements at the three near-road sites, the 1-hour averages of on-road BC concentrations were as much as an order of magnitude higher. The peak 1-minute average concentrations were two orders of magnitude higher for BC and were between two and six times higher for PM2.5 mass. The on-road concentrations of benzene, toluene, ethylbenzene, and xylenes (BTEX) during the summer were 3.5 +/- 0.7 and 1.2 +/- 0.6 times higher during morning and afternoon commuting periods, respectively, compared to annual average 24-hour concentrations measured at air toxic monitoring network sites. These ratios were higher during the fall, with smaller diurnal differences (4.8 +/- 0.7 and 3.9 +/- 0.6 for morning and afternoon commuting periods, respectively). Ratios similar to those for BTEX were obtained for 1,3-butadiene (BD) and styrene. On-road concentrations of formaldehyde and acetaldehyde were up to two times higher than at air toxics monitoring sites, with fall ratios slightly higher than summer ratios. Chemical mass balance (CMB) receptor model calculations attributed the sum of BTEX almost exclusively to gasoline engine exhaust for on-road samples and all but 5% to 10% of the BTEX at the three near-road sites. CMB analysis attributed 46% to 52% (+/- 7) of the ambient total particulate carbon (TC) at the three near-road sites to diesel exhaust and 10% to 17% (+/- 7) to gasoline exhaust; it attributed about 90% of the ambient elemental carbon (EC) concentrations (measured as refractory carbon using the thermal evolution method) to diesel exhaust. Diesel particulate carbon (DPC) concentrations were estimated by multiplying the mean ratio of TC to EC from the source-dominated ambient samples collected on road on Terminal Island (1.30 +/- 0.28), which is located between the Long Beach and Los Angeles ports, with the measured ambient EC concentrations at the three near-road sites. DPC estimates from EC measurements correlate well with the diesel source contributions calculated with the CMB model. The indication from these apportionments that BC or EC is a good surrogate for diesel exhaust is further supported by the positive correlation of on-road BC concentrations with volumes of truck traffic. Traffic counts have been used in past health assessment studies as surrogates for estimating near-road exposure concentrations with appropriate weighting for proximity to the road. However, the results of this study show that it is necessary to account for the proportion of diesel trucks to total vehicular traffic because of the disproportionate contribution of diesel exhaust to BC and to directly emitted PM. Alternatively, easily measured pollutants such as CO and BC can serve as reasonable surrogates for MSATs (e.g., BTEX and BD) and DPC, respectively. Measuring CO and BC is a reasonably cost-effective approach to quantifying hot-spot exposure concentrations of MSATs that is perhaps more accurate than what is possible using only data from regional air quality monitoring stations or air quality modeling results. PMID:21608416

  18. Design and analysis of biomimetic joints for morphing of micro air vehicles.

    PubMed

    Grant, Daniel T; Abdulrahim, Mujahid; Lind, Rick

    2010-12-01

    Flight capability for micro air vehicles is rapidly maturing throughout the aviation community; however, mission capability has not yet matured at the same pace. Maintaining trim during a descent or in the presence of crosswinds remains challenging for fixed-wing aircraft but yet is routinely performed by birds. This paper presents an overview of designs that incorporate morphing to enhance their flight characteristics. In particular, a series of joints and structures is adopted from seagulls to alter either the dihedral or sweep of the wings and thus alter the flight characteristics. The resulting vehicles are able to trim with significantly increased angles of attack and sideslip compared to traditional fixed-wing vehicles. PMID:21098958

  19. Cleaning the air and improving health with hydrogen fuel-cell vehicles.

    PubMed

    Jacobson, M Z; Colella, W G; Golden, D M

    2005-06-24

    Converting all U.S. onroad vehicles to hydrogen fuel-cell vehicles (HFCVs) may improve air quality, health, and climate significantly, whether the hydrogen is produced by steam reforming of natural gas, wind electrolysis, or coal gasification. Most benefits would result from eliminating current vehicle exhaust. Wind and natural gas HFCVs offer the greatest potential health benefits and could save 3700 to 6400 U.S. lives annually. Wind HFCVs should benefit climate most. An all-HFCV fleet would hardly affect tropospheric water vapor concentrations. Conversion to coal HFCVs may improve health but would damage climate more than fossil/electric hybrids. The real cost of hydrogen from wind electrolysis may be below that of U.S. gasoline. PMID:15976300

  20. The Digital Twin Paradigm for Future NASA and U.S. Air Force Vehicles

    NASA Technical Reports Server (NTRS)

    Glaessgen, Edward H.; Stargel, D. S.

    2012-01-01

    Future generations of NASA and U.S. Air Force vehicles will require lighter mass while being subjected to higher loads and more extreme service conditions over longer time periods than the present generation. Current approaches for certification, fleet management and sustainment are largely based on statistical distributions of material properties, heuristic design philosophies, physical testing and assumed similitude between testing and operational conditions and will likely be unable to address these extreme requirements. To address the shortcomings of conventional approaches, a fundamental paradigm shift is needed. This paradigm shift, the Digital Twin, integrates ultra-high fidelity simulation with the vehicle s on-board integrated vehicle health management system, maintenance history and all available historical and fleet data to mirror the life of its flying twin and enable unprecedented levels of safety and reliability.

  1. LTA in the USA - Here's where it stands today. [lighter than air vehicles

    NASA Technical Reports Server (NTRS)

    Vittek, J. F., Jr.

    1974-01-01

    Lighter than air (LTA) vehicles were the first aircraft to fly and, until the disasters of the 1930s, were thought by many to be the primary mode of air transport. The history of LTA in the United States is briefly traced and the reasons for the current revival in interest are discussed. The focal point for this revival was the LTA Workshop hosted by M.I.T. under the joint sponsorship of the United States National Aeronautics and Space Administration, Navy, Federal Aviation Administration and Department of Transportation. The Workshop and its results are discussed in detail.

  2. Emissions of halocarbons from mobile vehicle air conditioning system in Hong Kong.

    PubMed

    Yan, H H; Guo, H; Ou, J M

    2014-08-15

    During the implementation of Montreal Protocol, emission inventories of halocarbons in different sectors at regional scale are fundamental to the formulation of relevant management strategy and inspection of the implementation efficiency. This study investigated the emission profile of halocarbons used in the mobile vehicle air conditioning system, the leading sector of refrigeration industry in terms of the refrigerant bank, market and emission, in the Hong Kong Special Administrative Region, using a bottom-up approach developed by 2006 IPCC Good Practice Guidance. The results showed that emissions of CFC-12 peaked at 53 tons ODP (Ozone Depletion Potential) in 1992 and then gradually diminished, whereas HFC-134a presented an increasing emission trend since 1990s and the emissions of HFC-134a reached 65,000 tons CO2-equivelant (CO2-eq) by the end of 2011. Uncertainty analysis revealed relatively high levels of uncertainties for special-purpose vehicles and government vehicles. Moreover, greenhouse gas (GHG) abatements under different scenarios indicated that potential emission reduction of HFC-134a ranged from 4.1 to 8.4 × 10(5)tons CO2-eq. The findings in this study advance our knowledge of halocarbon emissions from mobile vehicle air conditioning system in Hong Kong. PMID:24997256

  3. Vision-based local multi-resolution mapping and path planning for Miniature Air Vehicles

    Microsoft Academic Search

    Huili Yu; Randal W. Beard; Jeffrey Byrne

    2009-01-01

    Miniature air vehicles (MAVs) are often used for low altitude flights where unknown obstacles might be encountered. Path planning and obstacle avoidance for MAVs involve planning a feasible path from an initial state to a goal state while avoiding obstacles in the environment. This paper presents a vision-based local multi-resolution mapping and path planning technique for MAVs using a forward-looking

  4. Numerical and Experimental Modal Analysis Applied to the Membrane of Micro Air Vehicles Pliant Wings

    Microsoft Academic Search

    Uttam Kumar Chakravarty; Roberto Albertani

    \\u000a Hyperelastic latex membrane is an integral structure of micro air vehicles and plays an important role in their wings performance.\\u000a This paper presents finite element analysis (FEA) models for characterizing latex hyperelastic membrane at both static and\\u000a dynamic loadings, validated by experimental results. The membrane at different pre-tension levels are attached with a circular\\u000a steel ring and statically loaded using

  5. Computer program development specification for the air traffic control subsystem of the Man-Vehicle Systems Research Facility.

    E-print Network

    Massachusetts Institute of Technology. Flight Transportation Laboratory

    1982-01-01

    Functional summary: The Air Traffic Control (ATC) Subsystem of the Man-Vehicle System Research Facility (MVSRF) is a hardware/software complex which provides the MVSRF with the capability of simulating the multi-aircraft, ...

  6. 21 CFR 874.1100 - Earphone cushion for audiometric testing.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...cushion for audiometric testing is a device that is used to cover an audiometer earphone during audiometric testing to provide an acoustic coupling (sound connection path) between the audiometer earphone and the patient's ear. (b) Classification....

  7. 49 CFR 215.129 - Defective cushioning device.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Freight Car Components Draft System § 215.129 Defective... A railroad may not place or continue in service a car if it has a cushioning device that is— (a)...

  8. 49 CFR 215.129 - Defective cushioning device.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Freight Car Components Draft System § 215.129 Defective... A railroad may not place or continue in service a car if it has a cushioning device that is— (a)...

  9. 49 CFR 215.129 - Defective cushioning device.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Freight Car Components Draft System § 215.129 Defective... A railroad may not place or continue in service a car if it has a cushioning device that is— (a)...

  10. 49 CFR 215.129 - Defective cushioning device.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Freight Car Components Draft System § 215.129 Defective... A railroad may not place or continue in service a car if it has a cushioning device that is— (a)...

  11. 49 CFR 215.129 - Defective cushioning device.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Freight Car Components Draft System § 215.129 Defective... A railroad may not place or continue in service a car if it has a cushioning device that is— (a)...

  12. Using Local and Regional Air Quality Modeling and Source Apportionment Tools to Evaluate Vehicles and Biogenic Emission Factors 

    E-print Network

    Kota, Sri H

    2014-07-25

    and inventories of CO, NO_(x) and VOCs from on-road vehicles estimated by vehicle emission factor models and biogenic emissions of isoprene estimated by a popular biogenic emission model are evaluated using local and regional scale air quality modeling and source...

  13. A vision-based autopilot for a miniature air vehicle: joint speed control and lateral obstacle avoidance

    Microsoft Academic Search

    J. Serres; D. Dray; Franck Ruffier; Nicolas H. Franceschini

    2008-01-01

    In our project on the autonomous guidance of Micro-Air Vehicles (MAVs) in confined indoor and outdoor environments, we have\\u000a developed a vision based autopilot, with which a miniature hovercraft travels along a corridor by automatically controlling\\u000a both its speed and its clearance from the walls. A hovercraft is an air vehicle endowed with natural roll and pitch stabilization\\u000a characteristics, in

  14. Landing Characteristics of a Re-entry Vehicle with Canted Multiple Air Bag Load Alleviation System

    NASA Technical Reports Server (NTRS)

    1963-01-01

    Investigation of the Landing Characteristics of a Re-entry Vehicle Having a Canted Multiple Air Bag Load Alleviation System. An investigation was made to determine the landing-impact characteristics of a reentry vehicle having a multiple-air-bag load-alleviation system. A 1/16-scale dynamic model having four canted air bags was tested at flight-path angles of 90 degrees (vertical), 45 degrees, and 27 degrees for a parachute or paraglider vertical letdown velocity of 30 feet per second (full scale). Landings were made on concrete at attitudes ranging from -l5 degrees to 20 degrees. The friction coefficient between the model heat shield and the concrete was approximately 0.4. An aluminum diaphragm, designed to rupture at 10.8 pounds per square inch gage, was used to maintain initial pressure in the air bags for a short time period. [Entire movie available on DVD from CASI as Doc ID 20070030986. Contact help@sti.nasa.gov

  15. High Altitude Long Endurance Air Vehicle Analysis of Alternatives and Technology Requirements Development

    NASA Technical Reports Server (NTRS)

    Nickol, Craig L.; Guynn, Mark D.; Kohout, Lisa L.; Ozoroski, Thomas A.

    2007-01-01

    The objective of this study was to develop a variety of High Altitude Long Endurance (HALE) Unmanned Aerial Vehicle (UAV) conceptual designs for two operationally useful missions (hurricane science and communications relay) and compare their performance and cost characteristics. Sixteen potential HALE UAV configurations were initially developed, including heavier-than-air (HTA) and lighter-than-air (LTA) concepts with both consumable fuel and solar regenerative (SR) propulsion systems. Through an Analysis of Alternatives (AoA) down select process, the two leading consumable fuel configurations (one each from the HTA and LTA alternatives) and an HTA SR configuration were selected for further analysis. Cost effectiveness analysis of the consumable fuel configurations revealed that simply maximizing vehicle endurance can lead to a sub-optimum system solution. An LTA concept with a hybrid propulsion system (solar arrays and a hydrogen-air proton exchange membrane fuel cell) was found to have the best mission performance; however, an HTA diesel-fueled wing-body-tail configuration emerged as the preferred consumable fuel concept because of the large size and technical risk of the LTA concept. The baseline missions could not be performed by even the best HTA SR concept. Mission and SR technology trade studies were conducted to enhance understanding of the potential capabilities of such a vehicle. With near-term technology SR-powered HTA vehicles are limited to operation in favorable solar conditions, such as the long days and short nights of summer at higher latitudes. Energy storage system specific energy and solar cell efficiency were found to be the key technology areas for enhancing HTA SR performance.

  16. Design of a Flush Airdata System (FADS) for the Hypersonic Air Launched Option (HALO) Vehicle

    NASA Technical Reports Server (NTRS)

    Whitmore, Stephen A.; Moes, Timothy R.; Deets, Dwain A. (Technical Monitor)

    1994-01-01

    This paper presents a design study for a pressure based Flush airdata system (FADS) on the Hypersonic Air Launched Option (HALO) Vehicle. The analysis will demonstrate the feasibility of using a pressure based airdata system for the HALO and provide measurement uncertainty estimates along a candidate trajectory. The HALO is a conceived as a man-rated vehicle to be air launched from an SR-71 platform and is proposed as a testbed for an airbreathing hydrogen scramjet. A feasibility study has been performed and indicates that the proposed trajectory is possible with minimal modifications to the existing SR71 vehicle. The mission consists of launching the HALO off the top of an SR-71 at Mach 3 and 80,000 ft. A rocket motor is then used to accelerate the vehicle to the test condition. After the scramjet test is completed the vehicle will glide to a lakebed runway landing. This option provides reusability of the vehicle and scramjet engine. The HALO design will also allow for various scramjet engine and flowpath designs to be flight tested. For the HALO flights, measurements of freestream airdata are considered to be a mission critical to perform gain scheduling and trajectory optimization. One approach taken to obtaining airdata involves measurement of certain parameters such as external atmospheric winds, temperature, etc to estimate the airdata quantities. This study takes an alternate approach. Here the feasibility of obtaining airdata using a pressure-based flush airdata system (FADS) methods is assessed. The analysis, although it is performed using the HALO configuration and trajectory, is generally applicable to other hypersonic vehicles. The method to be presented offers the distinct advantage of inferring total pressure, Mach number, and flow incidence angles, without stagnating the freestream flow. This approach allows for airdata measurements to be made using blunt surfaces and significantly diminishes the heating load at the sensor. In the FADS concept a matrix of flush ports is placed in the vicinity of the aircraft nose, and the airdata are inferred indirectly from the measured pressures.

  17. Differences in the Effectiveness of Frontal Air Bags by Body Size Among Adults Involved in Motor Vehicle Crashes

    Microsoft Academic Search

    Craig D. Newgard; K. John McConnell

    2008-01-01

    Objective. There is concern that small stature occupants (particularly women) involved in motor vehicle crashes (MVCs) may be at risk of injury or death from frontal air bags, though evidence to substantiate this concern is lacking. We sought to assess how occupant body size (measured through height and weight) affects air bag effectiveness in mitigating the risk of serious injury,

  18. Spatially- and Temporally-Resolved Measurements of Roadway Air Pollution Using a Zero-Emission Electric Vehicle

    EPA Science Inventory

    Vehicle-related air pollution has an intrinsically dynamic nature. Recent field measurements and modeling work have demonstrated that near-road topography may modify levels of air pollutants reaching populations residing and working in close proximity to roadways. However, the ma...

  19. Structural Sizing of a 25,000-lb Payload, Air-Breathing Launch Vehicle For Single-Stage-To-Orbit

    NASA Technical Reports Server (NTRS)

    Roche, Joseph M.; Kosareo, Daniel N.; Palac, Don (Technical Monitor)

    2000-01-01

    In support of NASA's Air-Breathing Launch Vehicle (ABLV) study, a 25,000-lb payload version of the GTX (formerly Trailblazer) reference vehicle concept was developed. The GTX is a vertical lift-off, reusable, single-stage-to-orbit launch vehicle concept that uses hypersonic air-breathing propulsion in a rocket-based combined-cycle (RBCC) propulsion system to reduce the required propellant fraction. To achieve this goal the vehicle and propulsion system must be well integrated both aerodynamically and structurally to reduce weight. This study demonstrates the volumetric and structural efficiency of a vertical takeoff, horizontal landing, hypersonic vehicle with a circular cross section. A departure from the lifting body concepts, this design philosophy is even extended to the engines, which have semicircular nacelles symmetrically mounted on the vehicle. Material candidates with a potential for lightweight and simplicity have been selected from a set of near term technologies (5 to 10 years). To achieve the mission trajectory, preliminary weight estimates show the vehicle's gross lift-off weight is 1.26 x 10(exp 6) lb. The structural configuration of the GTX vehicle and its propulsion system are described. The vehicle design benefits are presented, and key technical issues are highlighted.

  20. Structural Sizing of a 25,000-lb Payload, Air-breathing Launch Vehicle for Single-stage-to-orbit

    NASA Technical Reports Server (NTRS)

    Roche, Joseph M.; Kosareo, Daniel N.

    2001-01-01

    In support of NASA's Air-Breathing Launch Vehicle (ABLV) study, a 25,000-lb payload version of the GTX (formerly Trailblazer) reference vehicle concept was developed. The GTX is a vertical lift-off, reusable, single-stage-to-orbit launch vehicle concept that uses hypersonic air-breathing propulsion in a rocket-based combined-cycle (RBCC) propulsion system to reduce the required propellant fraction. To achieve this goal the vehicle and propulsion system must be well integrated both aerodynamically and structurally to reduce weight. This study demonstrates the volumetric and structural efficiency of a vertical takeoff, horizontal landing, hypersonic vehicle with a circular cross section. A departure from the lifting body concepts, this design philosophy is even extended to the engines, which have semicircular nacelles symmetrically mounted on the vehicle. Material candidates with a potential for lightweight and simplicity have been selected from a set of near term technologies (five to ten years). To achieve the mission trajectory, preliminary weight estimates show the vehicle's gross lift-off weight is 1.26 x 10(exp 6) lb. The structural configuration of the GTX vehicle and its propulsion system are described. The vehicle design benefits are presented, and key technical issues are highlighted.

  1. Electric vehicles

    Microsoft Academic Search

    M. J. Riezenman

    1992-01-01

    The renewed interest in electric vehicles (EVs) in the wake of the California Air Resources Board mandate that 2% of the vehicles lighter than 3750 lb (1700 kg) sold by each manufacturer in that state in 1998 be zero-emission vehicles is examined. The reasons why replacing an internal combustion vehicle (ICV) with an electrically powered equivalent greatly reduces air pollution,

  2. Design of an airborne launch vehicle for an air launched space booster

    NASA Technical Reports Server (NTRS)

    Chao, Chin; Choi, Rich; Cohen, Scott; Dumont, Brian; Gibin, Mauricius; Jorden, Rob; Poth, Stefan

    1993-01-01

    A conceptual design is presented for a carrier vehicle for an air launched space booster. This airplane is capable of carrying a 500,000 pound satellite launch system to an altitude over 40,000 feet for launch. The airplane features a twin fuselage configuration for improved payload and landing gear integration, a high aspect ratio wing for maneuverability at altitude, and is powered by six General Electric GE-90 engines. The analysis methods used and the systems employed in the airplane are discussed. Launch costs are expected to be competitive with existing launch systems.

  3. Model Update of a Micro Air Vehicle (MAV) Flexible Wing Frame with Uncertainty Quantification

    NASA Technical Reports Server (NTRS)

    Reaves, Mercedes C.; Horta, Lucas G.; Waszak, Martin R.; Morgan, Benjamin G.

    2004-01-01

    This paper describes a procedure to update parameters in the finite element model of a Micro Air Vehicle (MAV) to improve displacement predictions under aerodynamics loads. Because of fabrication, materials, and geometric uncertainties, a statistical approach combined with Multidisciplinary Design Optimization (MDO) is used to modify key model parameters. Static test data collected using photogrammetry are used to correlate with model predictions. Results show significant improvements in model predictions after parameters are updated; however, computed probabilities values indicate low confidence in updated values and/or model structure errors. Lessons learned in the areas of wing design, test procedures, modeling approaches with geometric nonlinearities, and uncertainties quantification are all documented.

  4. Operational benefits from the Terminal Configured Vehicle. [aircraft equipment for air traffic improvement

    NASA Technical Reports Server (NTRS)

    Reeder, J. P.; Schmitz, R. A.

    1978-01-01

    The objective of Terminal Configured Vehicle (TCV) research activity is to provide improvements which lead to increased airport and runway capacity, increasing air traffic controller productivity, energy efficient terminal area operations, reduced weather minima with safety, and reduced community noise by use of appropriate measures. Some early results of this research activity are discussed, and present and future research needs to meet the broad research objectives are defined. Particular consideration is given to the development of the TCV B-737 aircraft, the integration of the TCV with MLS, and avionics configurations, flight profiles, and manually controlled approaches for TCV. Some particular test demonstrations are discussed.

  5. Formation of photochemical air pollution in central California 1. Development of a revised motor vehicle emission inventory

    NASA Astrophysics Data System (ADS)

    Marr, Linsey C.; Black, Douglas R.; Harley, Robert A.

    2002-03-01

    Photochemical air pollution problems have proved difficult to understand and control in central California. A major source of uncertainty is the rate of precursor volatile organic compounds and NOx emissions, especially from motor vehicles. We develop alternative emissions estimates for on-road motor vehicles in 1990, using fuel sales data, emission factors measured in on-road studies, and ambient pollutant ratios, for a region that includes the San Francisco Bay and San Joaquin Valley air basins and Sacramento County. Fuel-based emissions estimates are compared with predictions of California's most recent motor vehicle emission factor model (EMFAC) and with an inventory that has been used in previous regional-scale photochemical modeling studies. The fuel-based inventory contains 10-50% less CO, 40-100% more nonmethane organic compounds, and 10-20% less NOx than estimated both by EMFAC and the photochemical modeling inventory. We also describe new temporal distributions of vehicle emissions by hour and day of week. Diesel trucks, a major source of NOx, have a broad midday peak in emissions on weekdays, in contrast to passenger vehicles, which show morning and afternoon commuter peaks. While passenger vehicle travel is similar on weekdays and weekends, diesel truck activity and emissions decrease by 70-80% on weekends. Vehicle emission rates and their temporal patterns are linked to a regional photochemical air pollution episode that spans a weekend in August 1990.

  6. Flexible Wing Base Micro Aerial Vehicles: Vision-Guided Flight Stability and Autonomy for Micro Air Vehicles

    NASA Technical Reports Server (NTRS)

    Ettinger, Scott M.; Nechyba, Michael C.; Ifju, Peter G.; Wazak, Martin

    2002-01-01

    Substantial progress has been made recently towards design building and test-flying remotely piloted Micro Air Vehicle's (MAVs). We seek to complement this progress in overcoming the aerodynamic obstacles to.flight at very small scales with a vision stability and autonomy system. The developed system based on a robust horizon detection algorithm which we discuss in greater detail in a companion paper. In this paper, we first motivate the use of computer vision for MAV autonomy arguing that given current sensor technology, vision may he the only practical approach to the problem. We then briefly review our statistical vision-based horizon detection algorithm, which has been demonstrated at 30Hz with over 99.9% correct horizon identification. Next we develop robust schemes for the detection of extreme MAV attitudes, where no horizon is visible, and for the detection of horizon estimation errors, due to external factors such as video transmission noise. Finally, we discuss our feed-back controller for self-stabilized flight, and report results on vision autonomous flights of duration exceeding ten minutes.

  7. Design and development considerations for biologically inspired flapping-wing micro air vehicles

    NASA Astrophysics Data System (ADS)

    Jones, Kevin D.; Platzer, Max F.

    In this paper, the decade of numerical and experimental investigations leading to the development of the authors' unique flapping-wing micro air vehicle is summarized. Early investigations included the study of boundary layer energization by means of a small flapping foil embedded in a flat-plate boundary layer, the reduction of the recirculatory flow region behind a backward-facing step by means of a small flapping foil, and the reduction or suppression of flow separation behind blunt or cusped airfoil trailing edges by flapping a small foil located in the wake flow region. These studies were followed by systematic investigations of the aerodynamic characteristics of single flapping airfoils and airfoil combinations. These unsteady flows were described using flow visualization, laser-Doppler velocimetry in addition to panel and Navier-Stokes computations. It is then shown how this flapping-wing database was used to conceive, design and develop a micro air vehicle which has a fixed wing for lift and two flapping wings for thrust generation. While animal flight is characterized by a coupled force generation, the present design appears to separate lift and thrust. However, in fact, the performance of one surface is closely coupled to the other surfaces.

  8. Design and development considerations for biologically inspired flapping-wing micro air vehicles

    NASA Astrophysics Data System (ADS)

    Jones, Kevin D.; Platzer, Max F.

    2009-05-01

    In this paper, the decade of numerical and experimental investigations leading to the development of the authors’ unique flapping-wing micro air vehicle is summarized. Early investigations included the study of boundary layer energization by means of a small flapping foil embedded in a flat-plate boundary layer, the reduction of the recirculatory flow region behind a backward-facing step by means of a small flapping foil, and the reduction or suppression of flow separation behind blunt or cusped airfoil trailing edges by flapping a small foil located in the wake flow region. These studies were followed by systematic investigations of the aerodynamic characteristics of single flapping airfoils and airfoil combinations. These unsteady flows were described using flow visualization, laser-Doppler velocimetry in addition to panel and Navier-Stokes computations. It is then shown how this flapping-wing database was used to conceive, design and develop a micro air vehicle which has a fixed wing for lift and two flapping wings for thrust generation. While animal flight is characterized by a coupled force generation, the present design appears to separate lift and thrust. However, in fact, the performance of one surface is closely coupled to the other surfaces.

  9. Air quality impacts of climate mitigation: UK policy and passenger vehicle choice.

    PubMed

    Mazzi, Eric A; Dowlatabadi, Hadi

    2007-01-15

    In 2001-2002 the UK began taxing vehicles according to CO2 emission rates. Since then, there has been a significant increase in consumer choice of small cars and diesel engines. We estimate CO2 reductions and air quality impacts resulting from UK consumers switching from petrol to diesel cars from 2001 to 2020. Annual reductions of 0.4 megatons (Mt) of CO2 and 1 million barrels of oil are estimated from switching to diesels. However, diesels emit higher levels of particulate matter estimated to result in 90 deaths annually (range 20-300). We estimate 570, 460, and 0 additional deaths per Mt of CO2 abated, for Euro III, Euro IV, and post-Euro IV emission class vehicles, respectively. CO2 policies are suspected to have contributed substantially to diesel growth, but the magnitude of impact has yet to be quantified rigorously. To the extent that CO2 policies contribute to diesel growth, coordinating CO2 controls with tightening of emission standards would save lives. This research shows that climate policy, while reducing fuel use and CO2, does not always ensure ancillary health benefits. Lessons from the UK can help inform policies designed elsewhere which strive to balance near-term ambient air quality and health with long-term climate mitigation. PMID:17310696

  10. Lightweight, fire-retardant, crashworthy aircraft seat cushioning

    NASA Technical Reports Server (NTRS)

    Haslim, Leonard A.; Mcdonough, Paul T.

    1991-01-01

    A two page discussion of non-aerospace seating applications and the design of NASA's safety seat cushioning (SSC) is presented. The SSC was designed for both safety and comfort in order to replace polyurethane cushioning which is flammable and produces lethal fumes upon combustion. The SSC is composed of advanced fabric reinforced composites and is lightweight, fire-retardent, and crashworthy. The seat design consists of central elliptical tubular spring supports made of fire-resistant and fatigue-durable composites surrounded by a fire-blocking sheath. The cushioning is made crashworthy by incorporating energy-absorbing, viscoelastic layers between the nested, elliptical-hoop springs. The design is intended to provide comfortable seating that meets aircraft-loading requirements without using the conventional polyurethane materials. The designs of an aircraft seat and structural components of the SSC are also presented.

  11. Vehicle cabin cooling system for capturing and exhausting heated boundary layer air from inner surfaces of solar heated windows

    DOEpatents

    Farrington, Robert B. (Golden, CO); Anderson, Ren (Broomfield, CO)

    2001-01-01

    The cabin cooling system includes a cooling duct positioned proximate and above upper edges of one or more windows of a vehicle to exhaust hot air as the air is heated by inner surfaces of the windows and forms thin boundary layers of heated air adjacent the heated windows. The cabin cooling system includes at least one fan to draw the hot air into the cooling duct at a flow rate that captures the hot air in the boundary layer without capturing a significant portion of the cooler cabin interior air and to discharge the hot air at a point outside the vehicle cabin, such as the vehicle trunk. In a preferred embodiment, the cooling duct has a cross-sectional area that gradually increases from a distal point to a proximal point to the fan inlet to develop a substantially uniform pressure drop along the length of the cooling duct. Correspondingly, this cross-sectional configuration develops a uniform suction pressure and uniform flow rate at the upper edge of the window to capture the hot air in the boundary layer adjacent each window.

  12. Neighborhood-scale air quality impacts of emissions from motor vehicles and aircraft

    NASA Astrophysics Data System (ADS)

    Choi, Wonsik; Hu, Shishan; He, Meilu; Kozawa, Kathleen; Mara, Steve; Winer, Arthur M.; Paulson, Suzanne E.

    2013-12-01

    A mobile monitoring platform (MMP) was used to measure real-time air pollutant concentrations in different built environments of Boyle Heights (BH, a lower-income community enclosed by several freeways); Downtown Los Angeles (DTLA, adjacent to BH with taller buildings and surrounded by several freeways); and West Los Angeles (WLA, an affluent community traversed by two freeways) in summer afternoons of 2008 and 2011 (only for WLA). Significant inter-community and less significant but observable intra-community differences in traffic-related pollutant concentrations were observed both in the residential neighborhoods studied and on their arterial roadways between BH, DTLA, and WLA, particularly for ultrafine particles (UFP). HEV, defined as vehicles creating plumes with concentrations more than three standard deviations from the adjusted local baseline, were encountered during 6-13% of sampling time, during which they accounted for 17-55% of total UFP concentrations both on arterial roadways and in residential neighborhoods. If instead a single threshold value is used to define HEVs in all areas, HEV's were calculated to make larger contributions to UFP concentrations in BH than other communities by factors of 2-10 or more. Santa Monica Airport located in WLA appears to be a significant source for elevated UFP concentrations in nearby residential neighborhoods 80-400 m downwind. In the WLA area, we also showed, on a neighborhood scale, striking and immediate reductions in particulate pollution (?70% reductions in both UFP and, somewhat surprisingly, PM2.5), corresponding to dramatic decreases in traffic densities during an I-405 closure event (“Carmageddon”) compared to non-closure Saturday levels. Although pollution reduction due to decreased traffic is not unexpected, this dramatic improvement in particulate pollution provides clear evidence air quality can be improved through strategies such as heavy-duty-diesel vehicle retrofits, earlier retirement of HEV, and transition to electric vehicles and alternative fuels, with corresponding benefits for public health.

  13. The potential impacts of electric vehicles on air quality in the urban areas of Barcelona and Madrid (Spain)

    NASA Astrophysics Data System (ADS)

    Soret, A.; Guevara, M.; Baldasano, J. M.

    2014-12-01

    This work analyses the potential air quality improvements resulting from three fleet electrification scenarios (?13, 26 and 40%) by replacing conventional vehicles with Electric Battery Vehicles (EBVs), Plug-in Hybrid Electric Vehicles (PHEVs) and Hybrid Electric Vehicles (HEVs). This study has been performed for the cities of Barcelona and Madrid (Spain), where road transport is the primary emission source. In these urban areas, several air quality problems are present, mainly related to NO2 and particulate matter. The WRF-ARW/HERMESv2/CMAQ model system has been applied at high spatial (1 × 1 km2) and temporal (1 h) resolution. The results show that fleet electrification offers a potential for emission abatement, especially related to NOx and CO. Regarding the more ambitious scenario (?40% fleet electrification), reductions of 11% and 17% of the total NOx emissions are observed in Barcelona and Madrid respectively. These emissions reductions involve air quality improvements in NO2 maximum hourly values up to 16%: reductions up to 30 and 35 ?g m-3 in Barcelona and Madrid, respectively. Furthermore, an additional scenario has been defined considering electric generation emissions associated with EBVs and PHEVs charging from a combined-cycle power plant. These charging emissions would produce slight NO2 increases in the downwind areas of <3 ?g m-3. Thus, fleet electrification would improve urban air quality even when considering emissions associated with charging electric vehicles. However, two further points should be considered. First, fleet electrification cannot be considered a unique solution, and other management strategies may be defined. This is especially important with respect to particulate matter emissions, which are not significantly reduced by fleet electrification (<5%) due to the high weight of non-exhaust emissions. Second, a significant introduction of electric vehicles (26-40%) involving all vehicle categories is required to improve urban air quality.

  14. Effects of heated seats in vehicles on thermal comfort during the initial warm-up period.

    PubMed

    Oi, Hajime; Tabata, Koji; Naka, Yasuhito; Takeda, Akira; Tochihara, Yutaka

    2012-03-01

    Eight subjects participated in a subjective experiment of eight conditions to investigate the effects of heated seats in vehicles on skin temperature, thermal sensation and thermal comfort during the initial warm-up period. The experimental conditions were designed as a combination of air temperature in the test room (5, 10, 15, or 20 °C) and heated seat (on/off). The heated seat was effective for improving thermal comfort during the initial warm-up period when air temperature was lower than 15 °C. Use of heated seats prevented decreases in or increased toe skin temperature. Heated seats also increased foot thermal sensation at 15 and 20 °C. Optimal thermal sensation in contact with the seat was higher when air temperature was lower. Optimal skin temperature in contact with the seat back was higher than that with the seat cushion. Moreover, these optimal skin temperatures were higher when air temperature was lower. PMID:21683338

  15. Experimental Investigation of a Shrouded Rotor Micro Air Vehicle in Hover and in Edgewise Gusts

    NASA Astrophysics Data System (ADS)

    Hrishikeshavan, Vikram

    Due to the hover capability of rotary wing Micro Air Vehicles (MAVs), it is of interest to improve their aerodynamic performance, and hence hover endurance (or payload capability). In this research, a shrouded rotor configuration is studied and implemented, that has the potential to offer two key operational benefits: enhanced system thrust for a given input power, and improved structural rigidity and crashworthiness of an MAV platform. The main challenges involved in realising such a system for a lightweight craft are: design of a lightweight and stiff shroud, and increased sensitivity to external flow disturbances that can affect flight stability. These key aspects are addressed and studied in order to assess the capability of the shrouded rotor as a platform of choice for MAV applications. A fully functional shrouded rotor vehicle (disk loading 60 N/ m2) was designed and constructed with key shroud design variables derived from previous studies on micro shrouded rotors. The vehicle weighed about 280 g (244 mm rotor diameter). The shrouded rotor had a 30% increase in power loading in hover compared to an unshrouded rotor. Due to the stiff, lightweight shroud construction, a net payload benefit of 20-30 g was achieved. The different components such as the rotor, stabilizer bar, yaw control vanes and the shroud were systematically studied for system efficiency and overall aerodynamic improvements. Analysis of the data showed that the chosen shroud dimensions was close to optimum for a design payload of 250 g. Risk reduction prototypes were built to sequentially arrive at the final configuration. In order to prevent periodic oscillations in ight, a hingeless rotor was incorporated in the shroud. The vehicle was successfully ight tested in hover with a proportional-integralderivative feedback controller. A flybarless rotor was incorporated for efficiency and control moment improvements. Time domain system identification of the attitude dynamics of the flybar and flybarless rotor vehicle was conducted about hover. Controllability metrics were extracted based on controllability gramian treatment for the flybar and flybarless rotor. In edgewise gusts, the shrouded rotor generated up to 3 times greater pitching moment and 80% greater drag than an equivalent unshrouded rotor. In order to improve gust tolerance and control moments, rotor design optimizations were made by varying solidity, collective, operating RPM and planform. A rectangular planform rotor at a collective of 18 deg was seen to offer the highest control authority. The shrouded rotor produced 100% higher control moments due to pressure asymmetry arising from cyclic control of the rotor. It was seen that the control margin of the shrouded rotor increased as the disk loading increased, which is however deleterious in terms of hover performance. This is an important trade-off that needs to be considered. The flight performance of the vehicle in terms of edgewise gust disturbance rejection was tested in a series of bench top and free ight tests. A standard table fan and an open jet wind tunnel setup was used for bench top setup. The shrouded rotor had an edgewise gust tolerance of about 3 m/s while the unshrouded rotor could tolerate edgewise gusts greater than 5 m/s. Free flight tests on the vehicle, using VICON for position feedback control, indicated the capability of the vehicle to recover from gust impulse inputs from a pedestal fan at low gust values (up to 3 m/s).

  16. Chitosan cushioned phospholipid membrane and its application in imaging ellipsometry based-biosensor

    NASA Astrophysics Data System (ADS)

    Zhang, Yibang; Chen, Yanyan; Jin, Gang

    2011-09-01

    Chitosan cushion can support the air stability of phospholipid membrane, but the problem of serum solubility of phospholipid membrane prevents it from use in serum detection applications. Poly (ethylene glycol) (PEG) shielding promises both stability and non-specific adsorption resistance for phospholipid membrane. An air stable phospholipid membrane microarray has been successfully fabricated on chitosan modified silicon wafer. We have demonstrated the potential application of PEGylated phospholipid membrane in imaging ellipsometry-based protein biosensor. Because of the strong resistance against non-specific adsorption of serum, antigens are immobilized onto the membrane surface through chemical activation and further bind their antibodies without using blocking agent. Taking advantage of the multiple and parallel reaction capabilities of microfluidic reactor system, we have assayed the binding by varying both the density of antigen on the membrane surface and the concentration of antibody in solution.

  17. Economic Analysis of a Japanese Air Pollution Regulation: An Optimal Retirement Problem under Vehicle Type Regulation in the NOx–Particulate Matter Law

    Microsoft Academic Search

    Kazuyuki Iwata; Toshi Arimura

    2008-01-01

    This paper empirically examines the vehicle type regulation that was introduced under the Automobile Nitrogen Oxides–Particulate Matter Law to mitigate air pollution problems in Japanese metropolitan areas. The vehicle type regulation effectively sets various timings of vehicle retirement by the first registration year and by type. However, there was no consideration of cost or efficiency in choosing the timing of

  18. Continuous high order sliding mode controller design for a flexible air-breathing hypersonic vehicle.

    PubMed

    Wang, Jie; Zong, Qun; Su, Rui; Tian, Bailing

    2014-05-01

    This paper investigates the problem of tracking control with uncertainties for a flexible air-breathing hypersonic vehicle (FAHV). In order to overcome the analytical intractability of this model, an Input-Output linearization model is constructed for the purpose of feedback control design. Then, the continuous finite time convergence high order sliding mode controller is designed for the Input-Output linearization model without uncertainties. In addition, a nonlinear disturbance observer is applied to estimate the uncertainties in order to compensate the controller and disturbance suppression, where disturbance observer and controller synthesis design is obtained. Finally, the synthesis of controller and disturbance observer is used to achieve the tracking for the velocity and altitude of the FAHV and simulations are presented to illustrate the effectiveness of the control strategies. PMID:24534328

  19. Monitoring of atmospheric aerosol emissions using a remotely piloted air vehicle (RPV)-Borne Sensor Suite

    SciTech Connect

    NONE

    1996-05-01

    We have developed a small sensor system, the micro-atmospheric measurement system ({mu}-AMS), to monitor and track aerosol emissions. The system was developed to fly aboard a remotely piloted air vehicle, or other mobile platform, to provide real-time particle measurements in effluent plumes and to collect particles for chemical analysis. The {mu}-AMS instrument measures atmospheric parameters including particle mass concentration and size distribution, temperature, humidity, and airspeed, altitude and position (by GPS receiver) each second. The sensor data are stored onboard and are also down linked to a ground station in real time. The {mu}-AMS is battery powered, small (8 in. dia x 36 in.), and lightweight (15 pounds). Aerosol concentrations and size distributions from above ground explosive tests, airbone urban pollution, and traffic-produced particulates are presented.

  20. A refuelable zinc/air battery for fleet electric vehicle propulsion

    NASA Astrophysics Data System (ADS)

    Cooper, John F.; Fleming, Dennis; Hargrove, Douglas; Koopman, Ronald; Peterman, Keith

    1995-04-01

    We report the development and on-vehicle testing of an engineering prototype zinc/air battery. The battery is refueled by periodic exchange of spent electrolyte for zinc particles entrained in fresh electrolyte. The technology is intended to provide a capability for nearly continuous vehicle operation, using the fleet's home base for 10 minute refuelings and zinc recycling instead of commercial infrastructure. In the battery, the zinc fuel particles are stored in hoppers, from which they are gravity fed into individual cells and completely consumed during discharge. A six-celled (7V) engineering prototype battery was combined with a 6 V lead/acid battery to form a parallel hybrid unit, which was tested in series with the 216 V battery of an electric shuttle bus over a 75 mile circuit. The battery has an energy density of 140 Wh/kg and a mass density of 1.5 kg/L. Cost, energy efficiency, and alternative hybrid configurations are discussed.

  1. The development of an experimental facility and investigation of rapidly maneuvering Micro-Air-Vehicle wings

    NASA Astrophysics Data System (ADS)

    Wilson, Lee Alexander

    Vertical Takeoff-and-Landing (VTOL) Micro Air Vehicles (MAVs) provide a versatile operational platform which combines the capabilities of fixed wing and rotary wing MAVs. In order to improve performance of these vehicles, a better understanding of the rapid transition between horizontal and vertical flight is required. This study examines the flow structures around the Mini-Vertigo VTOL MAV using flow visualization techniques. This will gives an understanding of the flow structures which dominate the flight dynamics of rapid pitching maneuvers. This study consists of three objectives: develop an experimental facility, use flow visualization to investigate the flow around the experimental subject during pitching, and analyze the results. The flow around the Mini-Vertigo VTOL MAV is dominated by the slipstream from its propellers. The slipstream delays LE separation and causes drastic deflection in the flow. While the frequency of the vortices shed from the LE and TE varies with flow speed, the non-dimensional frequency does not. It does, however, vary slightly with the pitching rate. These results are applicable across a wide range of flight conditions. The results correlate to previous research done to examine the aerodynamic forces on the MAV.

  2. The development of aluminum-air batteries for application in electric vehicles

    NASA Astrophysics Data System (ADS)

    Rudd, E. J.; Lott, S.

    1990-12-01

    The recently concluded program, jointly funded by ELTECH Research Corporation and the Department of Energy, focused upon the development of an aluminum-air battery system for electric vehicle applications. The operation of the aluminum-air battery involves the dissolution of aluminum to produce a current and aluminate. Initially the objectives were to evaluate and optimize the battery design that was developed prior to this program (designated as the B300 cell) and to design and evaluate the components of the auxiliary system. During the program, three additional tasks were undertaken, addressing needs identified by ELTECH and by Sandia National Laboratories. First, the capability to produce aluminum alloys as relatively large ingots (100 to 150 lbs), with the required electrochemical performance, was considered essential to the development of the battery. The second additional task was the adoption of an advanced cell (designated as the AT400 cell), designed by ELTECH in a different program. Finally, it was recognized that a system model would allow evaluation of the interactions of the several unit operations involved in the battery. Therefore, the development of a mathematical model, based upon material and energy balances for the battery, was undertaken. At a systems level, sufficient information was obtained in the completion of this program to support the design, fabrication and operation of a batch or solids-free battery system. For the first time, the components of the auxiliary system, i.e., a heat exchanger, carbon dioxide scrubber and hydrogen disposal technology, have been defined for a vehicle battery. Progress on each component or system is summarized in the following sections.

  3. Progress In Electromagnetics Research Symposium Proceedings, Cambridge, USA, July 58, 2010 635 A Telemetry Antenna System for Unmanned Air Vehicles

    E-print Network

    Yanikoglu, Berrin

    microstrip patch antennas [2] are preferred due to their high gain and wide impedance bandwidth. #12 with Agilent E8362B Precision Network Analyzer in 2.2­2.4 GHz frequency band. The antenna gain is obtained A Telemetry Antenna System for Unmanned Air Vehicles M. Dogan1, 2 and F. Ustuner1 1 TUBITAK, UEKAE, Kocaeli

  4. Heavy Metal Contamination of Soil, Plant and Air of Scrapyard of Discarded Vehicles at Zarqa City, Jordan

    Microsoft Academic Search

    Qasem M. Jaradat; Adnan Masadeh; Mohammed A. Zaitoun; Baheyah M. Maitah

    2005-01-01

    Ninety soil samples, forty plant samples (Anabasis articulata), and twenty air samples were collected from the scrap yard of discarded vehicles near Zarqa city, Jordan. These samples were analyzed for heavy metals: Cd, Pb, Zn, Cu, Mn, Al, and Fe. Longitudinal and vertical profiles of soil samples were studied. Generally, the levels of all heavy metals studied in the scrap

  5. Towed-body trajectory tracking in aerial recovery of micro air vehicle in the presence of wind

    Microsoft Academic Search

    Liang Sun; Randal W. Beard

    2011-01-01

    This paper presents a method for recovering Micro Air Vehicles (MAVs) in flight using a mothership and towed drogue, in which the mothership executes an orbit that places the drogue in a stable, slower orbit that can be tracked by a MAV. This paper is particularly challenging in the presence of wind. The equations of motion of the cable using

  6. The impact of China's vehicle emissions on regional air quality in 2000 and 2020: a scenario analysis

    NASA Astrophysics Data System (ADS)

    Saikawa, E.; Kurokawa, J.; Takigawa, M.; Mauzerall, D. L.; Horowitz, L. W.; Ohara, T.

    2011-04-01

    The number of vehicles in China has been increasing rapidly. We evaluate the impact of current and possible future vehicle emissions from China on Asian air quality. We modify the Regional Emission Inventory in Asia (REAS) for China's road transport sector in 2000 using updated Chinese data for vehicle numbers, annual mileage and emission factors. We develop two scenarios for 2020: a scenario where emission factors remain the same as they were before any regulation was implemented (business-as-usual, BAU), and a scenario where Euro 3 vehicle emission standards are applied to all vehicles (except motorcycles and rural vehicles). The Euro 3 scenario is an approximation of what may be the case in 2020 as, starting in 2008, all new gasoline and diesel vehicles in China (except motorcycles) were required to meet the Euro 3 emission standards. Using the Weather Research and Forecasting model coupled with Chemistry (WRF/Chem), we examine the regional air quality response to China's vehicle emissions in 2000 and in 2020 for the BAU and Euro 3 scenarios. We evaluate the 2000 model results with observations in Japan, China, Korea, and Russia. Under BAU in 2020, emissions of carbon monoxide (CO), nitrogen oxides (NOx), non-methane volatile organic compounds (NMVOCs), black carbon (BC) and organic carbon (OC) from China's vehicles more than double compared to the 2000 baseline. If all vehicles meet the Euro 3 regulations in 2020, however, these emissions are reduced by more than 50% relative to BAU. The implementation of stringent vehicle emission standards leads to a large, simultaneous reduction of the surface ozone (O3) mixing ratios and particulate matter (PM2.5) concentrations. In the Euro 3 scenario, surface O3 is reduced by more than 10 ppbv and surface PM2.5 is reduced by more than 10 ?g m-3 relative to BAU in Northeast China in all seasons. In spring, surface O3 mixing ratios and PM2.5 concentrations in neighboring countries are also reduced by more than 3 ppbv and 1 ?g m-3, respectively. We find that effective regulation of China's road transport sector will be of significant benefit for air quality both within China and across East Asia as well.

  7. The impact of China's vehicle emissions on regional air quality in 2000 and 2020: a scenario analysis

    NASA Astrophysics Data System (ADS)

    Saikawa, E.; Kurokawa, J.; Takigawa, M.; Borken-Kleefeld, J.; Mauzerall, D. L.; Horowitz, L. W.; Ohara, T.

    2011-09-01

    The number of vehicles in China has been increasing rapidly. We evaluate the impact of current and possible future vehicle emissions from China on Asian air quality. We modify the Regional Emission Inventory in Asia (REAS) for China's road transport sector in 2000 using updated Chinese data for the number of vehicles, annual mileage, and emission factors. We develop two scenarios for 2020: a scenario where emission factors remain the same as they were in 2000 (No-Policy, NoPol), and a scenario where Euro 3 vehicle emission standards are applied to all vehicles (except motorcycles and rural vehicles). The Euro 3 scenario is an approximation of what may be the case in 2020 as, starting in 2008, all new vehicles in China (except motorcycles) were required to meet the Euro 3 emission standards. Using the Weather Research and Forecasting model coupled with Chemistry (WRF/Chem), we examine the regional air quality response to China's vehicle emissions in 2000 and in 2020 for the NoPol and Euro 3 scenarios. We evaluate the 2000 model results with observations in Japan, China, Korea, and Russia. Under NoPol in 2020, emissions of carbon monoxide (CO), nitrogen oxides (NOx), non-methane volatile organic compounds (NMVOCs), black carbon (BC), and organic carbon (OC) from China's vehicles more than double compared to the 2000 baseline. If all vehicles meet the Euro 3 regulations in 2020, however, these emissions are reduced by more than 50% relative to NoPol. The implementation of stringent vehicle emission standards leads to a large, simultaneous reduction of the surface ozone (O3) mixing ratios and particulate matter (PM2.5) concentrations. In the Euro 3 scenario, surface O3 is reduced by more than 10 ppbv and surface PM2.5 is reduced by more than 10 ?g m-3 relative to NoPol in Northeast China in all seasons. In spring, surface O3 mixing ratios and PM2.5 concentrations in neighboring countries are also reduced by more than 3 ppbv and 1 ?g m-3, respectively. We find that effective regulation of China's road transport sector will be of significant benefit for air quality both within China and across East Asia as well.

  8. Potential benefits of oxygen-enriched intake air in a vehicle powered by a spark-ignition engine

    SciTech Connect

    Ng, H.K.; Sekar, R.R.

    1994-04-01

    A production vehicle powered by a spark-ignition engine (3.1-L Chevrolet Lumina, model year 1990) was tested. The test used oxygen-enriched intake air containing 25 and 28% oxygen by volume to determine (1) if the vehicle would run without difficulties and (2) if emissions benefits would result. Standard Federal Test Procedure (FTP) emissions test cycles were run satisfactorily. Test results of catalytic converter-out emissions (emissions out of the converter) showed that both carbon monoxide and hydrocarbons were reduced significantly in all three phases of the emissions test cycle. Test results of engine-out emissions (emissions straight out of the engine, with the converter removed) showed that carbon monoxide was significantly reduced in the cold phase. All emission test results were compared with those for normal air (21% oxygen). The catalytic converter also had an improved carbon monoxide conversion efficiency under the oxygen-enriched-air conditions. Detailed results of hydrocarbon speciation indicated large reductions in 1,3-butadiene, formaldehyde, acetaldehyde, and benzene from the engine with the oxygen-enriched air. Catalytic converter-out ozone was reduced by 60% with 25%-oxygen-content air. Although NO{sub x} emissions increased significantly, both for engine-out and catalytic converter-out emissions, we anticipate that they can be ameliorated in the near future with new control technologies. The automotive industry currently is developing exhaust-gas control technologies for an oxidizing environment; these technologies should reduce NO{sub x} emissions more efficiently in vehicles that use oxygen-enriched intake air. On the basis of estimates made from current data, several production vehicles that had low NO{sub x} emissions could meet the 2004 Tier II emissions standards with 25%-oxygen-content air.

  9. Potential benefits of oxygen-enriched intake air in a vehicle powered by a spark-ignition engine

    NASA Astrophysics Data System (ADS)

    Ng, H. K.; Sekar, R. R.

    1994-04-01

    A production vehicle powered by a spark-ignition engine (3.1-L Chevrolet Lumina, model year 1990) was tested. The test used oxygen-enriched intake air containing 25 and 28% oxygen by volume to determine (1) if the vehicle would run without difficulties and (2) if emissions benefits would result. Standard Federal Test Procedure (FTP) emissions test cycles were run satisfactorily. Test results of catalytic converter-out emissions (emissions out of the converter) showed that both carbon monoxide and hydrocarbons were reduced significantly in all three phases of the emissions test cycle. Test results of engine-out emissions (emissions straight out of the engine, with the converter removed) showed that carbon monoxide was significantly reduced in the cold phase. All emission test results were compared with those for normal air (21% oxygen). The catalytic converter also had an improved carbon monoxide conversion efficiency under the oxygen-enriched-air conditions. Detailed results of hydrocarbon speciation indicated large reductions in 1,3-butadiene, formaldehyde, acetaldehyde, and benzene from the engine with the oxygen-enriched air. Catalytic converter-out ozone was reduced by 60% with 25%-oxygen-content air. Although NO(x) emissions increased significantly, both for engine-out and catalytic converter-out emissions, we anticipate that they can be ameliorated in the near future with new control technologies. The automotive industry currently is developing exhaust-gas control technologies for an oxidizing environment; these technologies should reduce NO(x) emissions more efficiently in vehicles that use oxygen-enriched intake air. On the basis of estimates made from current data, several production vehicles that had low NO(x) emissions could meet the 2004 Tier 2 emissions standards with 25%-oxygen-content air.

  10. Networking Multiple Autonomous Air and Ocean Vehicles for Oceanographic Research and Monitoring

    NASA Astrophysics Data System (ADS)

    McGillivary, P. A.; Borges de Sousa, J.; Rajan, K.

    2013-12-01

    Autonomous underwater and surface vessels (AUVs and ASVs) are coming into wider use as components of oceanographic research, including ocean observing systems. Unmanned airborne vehicles (UAVs) are now available at modest cost, allowing multiple UAVs to be deployed with multiple AUVs and ASVs. For optimal use good communication and coordination among vehicles is essential. We report on the use of multiple AUVs networked in communication with multiple UAVs. The UAVs are augmented by inferential reasoning software developed at MBARI that allows UAVs to recognize oceanographic fronts and change their navigation and control. This in turn allows UAVs to automatically to map frontal features, as well as to direct AUVs and ASVs to proceed to such features and conduct sampling via onboard sensors to provide validation for airborne mapping. ASVs can also act as data nodes for communication between UAVs and AUVs, as well as collecting data from onboard sensors, while AUVs can sample the water column vertically. This allows more accurate estimation of phytoplankton biomass and productivity, and can be used in conjunction with UAV sampling to determine air-sea flux of gases (e.g. CO2, CH4, DMS) affecting carbon budgets and atmospheric composition. In particular we describe tests in July 2013 conducted off Sesimbra, Portugal in conjunction with the Portuguese Navy by the University of Porto and MBARI with the goal of tracking large fish in the upper water column with coordinated air/surface/underwater measurements. A thermal gradient was observed in the infrared by a low flying UAV, which was used to dispatch an AUV to obtain ground truth to demonstrate the event-response capabilities using such autonomous platforms. Additional field studies in the future will facilitate integration of multiple unmanned systems into research vessel operations. The strength of hardware and software tools described in this study is to permit fundamental oceanographic measurements of both ocean and atmosphere over temporal and spatial scales that have previously been problematic. The methods demonstrated are particularly suited to the study of oceanographic fronts and for tracking and mapping oil spills or plankton blooms. With the networked coordination of multiple autonomous systems, individual components may be changed out while ocean observations continue, allowing coarse to fine spatial studies of hydrographic features over temporal dimensions that would otherwise be difficult, including diurnal and tidal periods. Constraints on these methods currently involve coordination of data archiving systems into shipboard operating systems, familiarization of oceanographers with these methods, and existing nearshore airspace use constraints on UAVs. An important outcome of these efforts is to understand the methodology for using multiple heterogeneous autonomous vehicles for targeted science exploration.

  11. 64 FR 23906 - Control of Air Pollution From New Motor Vehicles; Compliance Programs for New Light-Duty Vehicles...

    Federal Register 2010, 2011, 2012, 2013, 2014

    1999-05-04

    ...approve each durability process. The Agency is requiring...manufacturer's durability processes to effectively predict...vehicles.'' During this review the Agency will evaluate...that the durability process will reflect in-use...improve the predictive capability of their...

  12. Population Density, Particulate Emission Characterization, and Impact on the Particulate Inventory of Smoking Vehicles in the South Coast Air Quality Management District

    Microsoft Academic Search

    Thomas D. Durbin; Matthew R. Smith; Joseph M. Norbeck; Timothy J. Truex

    1999-01-01

    The impact of high-particulate-emission vehicles on the total light-duty vehicle particulate emission inventory in the South Coast Air Quality Management District (SCAQMD) has been estimated by an analysis of the SCAQMD's CUT-SMOG database, a field survey of smoking vehicles, and particulate emissions testing of representative smoking vehicles. The field study, carried out at 61 sites throughout the SCAQMD, showed that

  13. Australian Air Breathing Propulsion Research for Hypersonic, Beamed Energy-Propelled Vehicles

    NASA Astrophysics Data System (ADS)

    Froning, David

    2010-05-01

    A three year laser-propelled vehicle analysis and design investigation has been begun in June, 2009 by Faculty and graduate students at the University of Adelaide under a Grant/Cooperative Agreement Award to the University of Adelaide by the Asian Office of Aerospace Research and Development (AOARD). The major objectives of thsis investigation are: (a) development of hypersonic, air breathing "lightcraft" with innovative air inlets that enable acceptable airflow capture and combustion, and acceptable cowl-lip heating rates during hot, high-speed, high angle-of-attack hypersonic flight; (b) yest of the most promising lightcraft and inlet design in the high power laser beam that is part of the shock tunnel facility at CTO Instituto in Brazil; and (c) plan a series of laser guided and propelled flights that achieve supersonic or higher speed at the Woomera Test Facility (WTF) in South Australia—using the existing WTF launching and tracking facilities and sponsor-provided laser pointing and tracking and illumination systems.

  14. Design and fabrication of microflap actuators for steering of micro air vehicles

    NASA Astrophysics Data System (ADS)

    Zimbru, George C.; Lee, Woo Ho; Popa, Dan O.

    2009-05-01

    This paper presents the design, analysis, and fabrication of an array of microflap actuators that can produce a substantial aerodynamic force for course corrections of Micro Air Vehicles (MAVs) and low speed projectiles. In the past, several actuation principles, including microjet, magnetic and bubble actuators, and flapping wings have been proposed, and had varying degrees of success. In this paper, we discuss the benefits and drawbacks of past attempts, and the technology that can be used to address the microflap steering problem. We propose a hybrid microflap actuation scheme that combines two types of actuators including: 1) a MEMS fabricated "active" microactuator connected to a microflap, and 2) a "passive" fluidic channel system that harvests the potential energy in the high pressure field on the leading edge of the MAV or high speed projectile to achieve a desired deflection. An array of microflap actuators was prototyped using silicon MEMS fabrication and microassembly. A Silicon On Insulator (SOI) wafer with 100 micron thick device layer was used to as a substrate material to fabricate microflap structures with springs. Front and back side DRIE process was used to etch and release the microstructures including microflaps. Then, the microactuator was assembled on top of the microflap. The static and dynamic behaviors of a microflap were measured using a laser displacement sensor and were compared to the analytic model. In the near future, a prototyped microflap will be tested inside of a wind tunnel to measure the lift and drag at various air speeds.

  15. Methods for measuring performance of vehicle cab air cleaning systems against aerosols and vapours.

    PubMed

    Bémer, D; Subra, I; Régnier, R

    2009-06-01

    Vehicle cabs equipped with an effective air cleaning and pressurization system, fitted to agricultural and off-road machineries, isolate drivers from the polluted environment, in which they are likely to work. These cabs provide protection against particulate and gaseous pollutants generated by these types of work activities. Two laboratory methods have been applied to determining the performance characteristics of two cabs of different design, namely, optical counting-based measurement of a potassium chloride (KCl) aerosol and fluorescein aerosol-based tracing. Results of cab confinement efficiency measurements agreed closely for these two methods implemented in the study. Measurements showed that high confinement efficiencies can be achieved with cabs, which are properly designed in ventilation/cleaning/airtightness terms. We also noted the importance of filter mounting airtightness, in which the smallest defect is reflected by significant degradation in cab performance. Determination of clean airflow rate by monitoring the decrease in test aerosol concentration in the test chamber gave excellent results. This method could represent an attractive alternative to methods involving gas tracing or air velocity measurement at blowing inlets. PMID:19406910

  16. Integration of Advanced Concepts and Vehicles Into the Next Generation Air Transportation System. Volume 1; Introduction, Key Messages, and Vehicle Attributes

    NASA Technical Reports Server (NTRS)

    Zellweger, Andres; Resnick, Herbert; Stevens, Edward; Arkind, Kenneth; Cotton William B.

    2010-01-01

    Raytheon, in partnership with NASA, is leading the way in ensuring that the future air transportation continues to be a key driver of economic growth and stability and that this system provides an environmentally friendly, safe, and effective means of moving people and goods. A Raytheon-led team of industry and academic experts, under NASA contract NNA08BA47C, looked at the potential issues and impact of introducing four new classes of advanced aircraft into the next generation air transportation system -- known as NextGen. The study will help determine where NASA should further invest in research to support the safe introduction of these new air vehicles. Small uncrewed or unmanned aerial systems (SUAS), super heavy transports (SHT) including hybrid wing body versions (HWB), very light jets (VLJ), and supersonic business jets (SSBJ) are the four classes of aircraft that we studied. Understanding each vehicle's business purpose and strategy is critical to assessing the feasibility of new aircraft operations and their impact on NextGen's architecture. The Raytheon team used scenarios created by aviation experts that depict vehicles in year 2025 operations along with scripts or use cases to understand the issues presented by these new types of vehicles. The information was then mapped into the Joint Planning and Development Office's (JPDO s) Enterprise Architecture to show how the vehicles will fit into NextGen's Concept of Operations. The team also identified significant changes to the JPDO's Integrated Work Plan (IWP) to optimize the NextGen vision for these vehicles. Using a proven enterprise architecture approach and the JPDO s Joint Planning Environment (JPE) web site helped make the leap from architecture to planning efficient, manageable and achievable. Very Light Jets flying into busy hub airports -- Supersonic Business Jets needing to climb and descend rapidly to achieve the necessary altitude Super-heavy cargo planes requiring the shortest common flight path -- are just a few of the potential new operations in the future National Airspace System. To assess the impact of these new scenarios on overall national airspace operations, the Raytheon team used the capabilities of a suite of tools such as NASA's Airspace Concepts Evaluation System (ACES), the Flight Optimization System (FLOPS), FAA's Aviation Environmental Design Tool (AEDT), Intelligent Automations Kinematic Trajectory Generator (KTG) and the Aviation Safety Risk Model (ASRM). Detailed metroplex modeling, surface delay models for super heavy transports, prioritized routing and corridors for supersonics business jets, and VLJ demand models are some of the models developed by the Raytheon team to study the effect of operating these new vehicles in the future NAS. Using this suite of models, several trade studies were conducted to evaluate these effects in terms of delays, equity in access, safety, and the environment. Looking at the impact of each vehicle, a number of critical issues were identified. The Raytheon team concluded that strict compliance to NextGen's 4-dimensional trajectory (4DT) management will be required to accommodate these vehicles unique operations and increased number of flights in the future air space system. The next section provides a discussion of this and the other key findings from our study.

  17. Autonomous Landing and Ingress of Micro-Air-Vehicles in Urban Environments Based on Monocular Vision

    NASA Technical Reports Server (NTRS)

    Brockers, Roland; Bouffard, Patrick; Ma, Jeremy; Matthies, Larry; Tomlin, Claire

    2011-01-01

    Unmanned micro air vehicles (MAVs) will play an important role in future reconnaissance and search and rescue applications. In order to conduct persistent surveillance and to conserve energy, MAVs need the ability to land, and they need the ability to enter (ingress) buildings and other structures to conduct reconnaissance. To be safe and practical under a wide range of environmental conditions, landing and ingress maneuvers must be autonomous, using real-time, onboard sensor feedback. To address these key behaviors, we present a novel method for vision-based autonomous MAV landing and ingress using a single camera for two urban scenarios: landing on an elevated surface, representative of a rooftop, and ingress through a rectangular opening, representative of a door or window. Real-world scenarios will not include special navigation markers, so we rely on tracking arbitrary scene features; however, we do currently exploit planarity of the scene. Our vision system uses a planar homography decomposition to detect navigation targets and to produce approach waypoints as inputs to the vehicle control algorithm. Scene perception, planning, and control run onboard in real-time; at present we obtain aircraft position knowledge from an external motion capture system, but we expect to replace this in the near future with a fully self-contained, onboard, vision-aided state estimation algorithm. We demonstrate autonomous vision-based landing and ingress target detection with two different quadrotor MAV platforms. To our knowledge, this is the first demonstration of onboard, vision-based autonomous landing and ingress algorithms that do not use special purpose scene markers to identify the destination.

  18. Autonomous landing and ingress of micro-air-vehicles in urban environments based on monocular vision

    NASA Astrophysics Data System (ADS)

    Brockers, Roland; Bouffard, Patrick; Ma, Jeremy; Matthies, Larry; Tomlin, Claire

    2011-06-01

    Unmanned micro air vehicles (MAVs) will play an important role in future reconnaissance and search and rescue applications. In order to conduct persistent surveillance and to conserve energy, MAVs need the ability to land, and they need the ability to enter (ingress) buildings and other structures to conduct reconnaissance. To be safe and practical under a wide range of environmental conditions, landing and ingress maneuvers must be autonomous, using real-time, onboard sensor feedback. To address these key behaviors, we present a novel method for vision-based autonomous MAV landing and ingress using a single camera for two urban scenarios: landing on an elevated surface, representative of a rooftop, and ingress through a rectangular opening, representative of a door or window. Real-world scenarios will not include special navigation markers, so we rely on tracking arbitrary scene features; however, we do currently exploit planarity of the scene. Our vision system uses a planar homography decomposition to detect navigation targets and to produce approach waypoints as inputs to the vehicle control algorithm. Scene perception, planning, and control run onboard in real-time; at present we obtain aircraft position knowledge from an external motion capture system, but we expect to replace this in the near future with a fully self-contained, onboard, vision-aided state estimation algorithm. We demonstrate autonomous vision-based landing and ingress target detection with two different quadrotor MAV platforms. To our knowledge, this is the first demonstration of onboard, vision-based autonomous landing and ingress algorithms that do not use special purpose scene markers to identify the destination.

  19. 66 FR 30830 - Control of Air Pollution From Motor Vehicles and New Motor Vehicle Engines; Revisions to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2001-06-08

    ...requiring vehicle manufacturers to; make full text emissions-related service information...information available. Rather than being a full text data base, the FedWorld data base...and up-load on its Web site the full text of all emission-related...

  20. Optimization of aircraft seat cushion fire blocking layers

    NASA Technical Reports Server (NTRS)

    Kourtides, D. A.; Parker, J. A.; Ling, A. C.; Hovatter, W. R.

    1983-01-01

    This report describes work completed by the National Aeronautics and Space Administration - for the Federal Aviation Administration Technical Center. The purpose of this work was to examine the potential of fire blocking mechanisms for aircraft seat cushions in order to provide an optimized seat configuration with adequate fire protection and minimum weight. Aluminized thermally stable fabrics were found to provide adequate fire protection when used in conjunction with urethane foams, while maintaining minimum weight and cost penalty.

  1. Energy dissipation characteristics of rubber crash cushion elements

    E-print Network

    Thompson, Michael Fowlkes

    1988-01-01

    OF SCIENCE December 1988 Major Subject: Civil Engineering ENERGY DISSIPATION CHARACTERISTICS OF RUBBER CRASH CUSHION ELEMENTS A Thesis by MICHAEL FOWLKES THOMPSON Approved as to style and content by: Paul N. Roschke (Chair of Committee) Hayes E. Ros... Cylinder With Rubber Stiffener 15 Energy Dissipation of Element With Rubber 47 49 1X Stiffener 50 16 Circular Cylinder With Rigid Stiffener 17 Sequential Deflection of Grouped C rcular and Square Cylinders 18 Energy Dissipation vs. Temperature, NR/EPDM...

  2. 77 FR 1892 - Approval and Promulgation of Air Quality Implementation Plans; State of Colorado; Motor Vehicle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-12

    ...Implementation Plan. (vi) The...Vehicle Emissions Inspection Program...IM240 emissions test will fail the...motor vehicle inspection and maintenance...on an IM240 inspection test. The IM240...maintenance plans for...

  3. 75 FR 38023 - Approval and Promulgation of Air Quality Implementation Plans; California; Motor Vehicle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ...Mandatory Smog Check Inspection and Test Procedures...Implementation Plan for California's...Motor Vehicle Inspection and Maintenance...motor vehicle inspection and maintenance...specifications and test procedures...Implementation Plan. [FR...

  4. Drive-by Motor Vehicle Emissions: Immediate Feedback in Reducing Air

    E-print Network

    Denver, University of

    /M program data has demonstrated that less than 10% of the vehicles on the road in the United States cause merged highway messaging and on-road vehicle emissions sensing into a cost- effective public information transportation energy consumption per vehicle-mile and per passenger-mile traveled. The difficulty in achieving

  5. Conservation equations and physical models for hypersonic air flows over the aeroassist flight experiment vehicle

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.

    1989-01-01

    The code development and application program for the Langley Aerothermodynamic Upwind Relaxation Algorithm (LAURA), with emphasis directed toward support of the Aeroassist Flight Experiment (AFE) in the near term and Aeroassisted Space Transfer Vehicle (ASTV) design in the long term is reviewed. LAURA is an upwind-biased, point-implicit relaxation algorithm for obtaining the numerical solution to the governing equations for 3-D, viscous, hypersonic flows in chemical and thermal nonequilibrium. The algorithm is derived using a finite volume formulation in which the inviscid components of flux across cell walls are described with Roe's averaging and Harten's entropy fix with second-order corrections based on Yee's Symmetric Total Variation Diminishing scheme. Because of the point-implicit relaxation strategy, the algorithm remains stable at large Courant numbers without the necessity of solving large, block tri-diagonal systems. A single relaxation step depends only on information from nearest neighbors. Predictions for pressure distributions, surface heating, and aerodynamic coefficients compare well with experimental data for Mach 10 flow over an AFE wind tunnel model. Predictions for the hypersonic flow of air in chemical and thermal nonequilibrium over the full scale AFE configuration obtained on a multi-domain grid are discussed.

  6. Fuel Cell Propulsion Systems for an All-electric Personal Air Vehicle

    NASA Technical Reports Server (NTRS)

    Kohout, Lisa L.; Schmitz, Paul C.

    2003-01-01

    There is a growing interest in the use of fuel cells as a power source for all-electric aircraft propulsion as a means to substantially reduce or eliminate environmentally harmful emissions. Among the technologies under consideration for these concepts are advanced proton exchange membrane and solid oxide fuel cells, alternative fuels and fuel processing, and fuel storage. This paper summarizes the results of a first-order feasibility study for an all-electric personal air vehicle utilizing a fuel cell-powered propulsion system. A representative aircraft with an internal combustion engine was chosen as a baseline to provide key parameters to the study, including engine power and subsystem mass, fuel storage volume and mass, and aircraft range. The engine, fuel tank, and associated ancillaries were then replaced with a fuel cell subsystem. Various configurations were considered including: a proton exchange membrane (PEM) fuel cell with liquid hydrogen storage; a direct methanol PEM fuel cell; and a direct internal reforming solid oxide fuel cell (SOFC)/turbine hybrid system using liquid methane fuel. Each configuration was compared to the baseline case on a mass and range basis.

  7. Fuel Cell Propulsion Systems for an All-Electric Personal Air Vehicle

    NASA Technical Reports Server (NTRS)

    Kohout, Lisa L.

    2003-01-01

    There is a growing interest in the use of fuel cells as a power source for all-electric aircraft propulsion as a means to substantially reduce or eliminate environmentally harmful emissions. Among the technologies under consideration for these concepts are advanced proton exchange membrane and solid oxide fuel cells, alternative fuels and fuel processing, and fuel storage. This paper summarizes the results of a first-order feasibility study for an all-electric personal air vehicle utilizing a fuel cell-powered propulsion system. A representative aircraft with an internal combustion engine was chosen as a baseline to provide key parameters to the study, including engine power and subsystem mass, fuel storage volume and mass, and aircraft range. The engine, fuel tank, and associated ancillaries were then replaced with a fuel cell subsystem. Various configurations were considered including: a proton exchange membrane (PEM) fuel cell with liquid hydrogen storage; a direct methanol PEM fuel cell; and a direct internal reforming solid oxide fuel cell (SOFC)/turbine hybrid system using liquid methane fuel. Each configuration was compared to the baseline case on a mass and range basis.

  8. Dynamic stability test results on an 0.024 scale B-1 air vehicle

    NASA Technical Reports Server (NTRS)

    Beeman, R. R.

    1972-01-01

    Dynamic longitudinal and lateral-directional stability characteristics of the B-1 air vehicle were investigated in three wind tunnels at the Langley Research Center. The main rotary derivatives were obtained for an angle of attack range of -3 degrees to +16 degrees for a Mach number range of 0.2 to 2.16. Damping in roll data could not be obtained at the supersonic Mach numbers. The Langley 7 x 10 foot high speed tunnel, the 8 foot transonic pressure tunnel, and the 4 foot Unitary Plan wind tunnel were the test sites. An 0.024 scale light-weight model was used on a forced oscillation type balance. Test Reynolds number varied from 474,000/ft to 1,550,000/ft. through the Mach number range tested. The results showed that the dynamic stability characteristics of the model in pitch and roll were generally satisfactory up to an angle attack of about +6 degrees. In the wing sweep range from 15 to 25 degrees the positive damping levels in roll deteriorated rapidly above +2 degrees angle of attack. This reduction in roll damping is believed to be due to the onset of separation over the wing as stall is approached.

  9. Roles of TGF? and BMP during valvulo–septal endocardial cushion formation

    Microsoft Academic Search

    Toshiyuki Yamagishi; Katsumi Ando; Hiroaki Nakamura

    2009-01-01

    The primordia of valves and the atrioventricular septum arise from endocardial cushion tissue that is formed in the outflow\\u000a tract (OFT) and in the atrioventricular (AV) regions during cardiogenesis. Abnormal development of the endocardial cushion\\u000a results in various congenital heart diseases. Endocardial epithelial–mesenchymal transformation (EMT) is a critical process\\u000a in cushion tissue formation and is regulated by many factors, such

  10. Dual rotor single- stator axial air gap PMSM motor/generator drive for high torque vehicles applications

    NASA Astrophysics Data System (ADS)

    Tutelea, L. N.; Deaconu, S. I.; Boldea, I.; Popa, G. N.

    2014-03-01

    The actual e - continuously variable transmission (e-CVT) solution for the parallel Hybrid Electric Vehicle (HEV) requires two electric machines, two inverters, and a planetary gear. A distinct electric generator and a propulsion electric motor, both with full power converters, are typical for a series HEV. In an effort to simplify the planetary-geared e-CVT for the parallel HEV or the series HEV we hereby propose to replace the basically two electric machines and their two power converters by a single, axial-air-gap, electric machine central stator, fed from a single PWM converter with dual frequency voltage output and two independent PM rotors, destined for hybrid electric vehicles (HEV) and military vehicles applications. The proposed topologies and the magneto-motive force analysis are the core of the paper.

  11. Development and evaluation of a new contoured cushion system with an optimized normalization algorithm.

    PubMed

    Li, Sujiao; Zhang, Zhengxiang; Wang, Jue

    2014-01-01

    Prevention of pressure sores remains a significant problem confronting spinal cord injury patients and the elderly with limited mobility. One vital aspect of this subject concerns the development of cushions to decrease pressure ulcers for seated patients, particularly those bound by wheelchairs. Here, we present a novel cushion system that employs interface pressure distribution between the cushion and the buttocks to design custom contoured foam cushion. An optimized normalization algorithm was proposed, with which interface pressure distribution was transformed into the carving depth of foam cushions according to the biomechanical characteristics of the foam. The shape and pressure-relief performance of the custom contoured foam cushions was investigated. The outcomes showed that the contoured shape of personalized cushion matched the buttock contour very well. Moreover, the custom contoured cushion could alleviate pressure under buttocks and increase subjective comfort and stability significantly. Furthermore, the fabricating method not only decreased the unit production cost but also simplified the procedure for manufacturing. All in all, this prototype seat cushion would be an effective and economical way to prevent pressure ulcers. PMID:25227054

  12. TGF? and BMP signaling in cardiac cushion formation: lessons from mice and chicken.

    PubMed

    Kruithof, Boudewijn P T; Duim, Sjoerd N; Moerkamp, Asja T; Goumans, Marie-José

    2012-07-01

    Cardiac cushion formation is crucial for both valvular and septal development. Disruption in this process can lead to valvular and septal malformations, which constitute the largest part of congenital heart defects. One of the signaling pathways that is important for cushion formation is the TGF? superfamily. The involvement of TGF? and BMP signaling pathways in cardiac cushion formation has been intensively studied using chicken in vitro explant assays and in genetically modified mice. In this review, we will summarize and discuss the role of TGF? and BMP signaling components in cardiac cushion formation. PMID:22656450

  13. Air-breathing hypersonic vehicle guidance and control studies: An integrated trajectory/control analysis methodology, phase 2

    NASA Technical Reports Server (NTRS)

    Hattis, Philip D.; Malchow, Harvey L.

    1992-01-01

    An integrated trajectory/control analysis algorithm has been used to generate trajectories and desired control strategies for two different hypersonic air-breathing vehicle models and orbit targets. Both models used cubic spline curve fit tabulated winged-cone accelerator vehicle representations. Near-fuel-optimal, horizontal takeoff trajectories, imposing a dynamic pressure limit of 1000 psf, were developed. The first model analysis case involved a polar orbit and included the dynamic effects of using elevons to maintain longitudinal trim. Analysis results indicated problems with the adequacy of the propulsion model and highlighted dynamic pressure/altitude instabilities when using vehicle angle of attack as a control variable. Also, the magnitude of computed elevon deflections to maintain trim suggested a need for alternative pitch moment management strategies. The second analysis case was reformulated to use vehicle pitch attitude relative to the local vertical as the control variable. A new, more realistic, air-breathing propulsion model was incorporated. Pitch trim calculations were dropped and an equatorial orbit was specified. Changes in flight characteristics due to the new propulsion model have been identified. Flight regimes demanding rapid attitude changes have been noted. Also, some issues that would affect design of closed-loop controllers were ascertained.

  14. Air-breathing hypersonic vehicle guidance and control studies; An integrated trajectory/control analysis methodology: Phase 1

    NASA Technical Reports Server (NTRS)

    Hattis, Philip D.; Malchow, Harvey L.

    1991-01-01

    A tool which generates optimal trajectory/control histories in an integrated manner is generically adapted to the treatment of single-stage-to-orbit air-breathing hypersonic vehicles. The methodology is implemented as a two point boundary value problem solution technique. Its use permits an assessment of an entire near-minimum-fuel trajectory and desired control strategy from takeoff to orbit while satisfying physically derived inequality constraints and while achieving efficient propulsive mode phasing. A simpler analysis strategy that partitions the trajectory into several boundary condition matched segments is also included to construct preliminary trajectory and control history representations with less computational burden than is required for the overall flight profile assessment. A demonstration was accomplished using a tabulated example (winged-cone accelerator) vehicle model that is combined with a newly developed multidimensional cubic spline data smoothing routine. A constrained near-fuel-optimal trajectory, imposing a dynamic pressure limit of 1000 psf, was developed from horizontal takeoff to 20,000 ft/sec relative air speed while aiming for a polar orbit. Previously unspecified propulsive discontinuities were located. Flight regimes demanding rapid attitude changes were identified, dictating control effector and closed-loop controller authority was ascertained after evaluating effector use for vehicle trim. Also, inadequacies in vehicle model representations and specific subsystem models with insufficient fidelity were determined based on unusual control characteristics and/or excessive sensitivity to uncertainty.

  15. Membrane-based air composition control for light-duty diesel vehicles : a benefit and cost assessment.

    SciTech Connect

    Poola, R.; Stork, K.

    1998-11-09

    This report presents the methodologies and results of a study conducted by Argonne National Laboratory (Argonne) to assess the benefits and costs of several membrane-based technologies. The technologies evaluated will be used in automotive emissions-control and performance-enhancement systems incorporated into light-duty diesel vehicle engines. Such engines are among the technologies that are being considered to power vehicles developed under the government-industry Partnership for a New Generation of Vehicles (PNGV). Emissions of nitrogen oxides (NO{sub x}) from diesel engines have long been considered a barrier to use of diesels in urban areas. Recently, particulate matter (PM) emissions have also become an area of increased concern because of new regulations regarding emissions of particulate matter measuring 2.5 micrometers or less (PM2.5). Particulates are of special concern for diesel engines in the PNGV program; the program has a research goal of 0.01 gram per mile (g/mi) of particulate matter emissions under the Federal Test Procedure (FTP) cycle. This extremely low level (one-fourth the level of the Tier II standard) could threaten the viability of using diesel engines as stand-alone powerplants or in hybrid-electric vehicles. The techniques analyzed in this study can reduce NO{sub x} and particulate emissions and even increase the power density of the diesel engines used in light-duty diesel vehicles. For nearly a decade, Argonne has been evaluating membrane-based methods to control the composition of air used in combustion. Membranes are the only practical method of modifying air composition for on-board use. The applicability of the technique depends strongly on both the technical and economic feasibility of implementing it on a vehicle. Over the past 10 years, significant technical advances have been made in the development of air-separation membranes. Researchers have developed and commercialized novel membrane materials that can efficiently separate air at the concentrations required for vehicle applications and have developed compact membrane modules that can be incorporated into vehicle design. Previous analysis by Argonne and others has demonstrated the effectiveness of oxygen enrichment at reducing PM, smoke, hydrocarbon (HC), and carbon monoxide (CO) emissions while increasing engine power output. Under appropriate oxygen-enriched operating conditions, diesel engines have achieved a net increase of 10-20% in power density and a decrease of 30-60% in PM emissions. Nitrogen-enriched air can be used as an alternative to exhaust gas recirculation to control NO{sub x} emissions and can also be used to generate a monatomic nitrogen plasma for exhaust post-treatment to reduce emissions of NO{sub x}. Argonne has recently identified an operating regime that can simultaneously reduce NO{sub x} and PM while increasing power output when oxygen-enriched combustion air is used. This promising technique, which will be verified by additional experimental work at Argonne (using a range of engine sizes), will require the use of membranes similar to those analyzed in this study.

  16. Emerging Fuel Cell Technology Being Developed: Offers Many Benefits to Air Vehicles

    NASA Technical Reports Server (NTRS)

    Walker, James F.; Civinskas, Kestutis C.

    2004-01-01

    Fuel cells, which have recently received considerable attention for terrestrial applications ranging from automobiles to stationary power generation, may enable new aerospace missions as well as offer fuel savings, quiet operations, and reduced emissions for current and future aircraft. NASA has extensive experience with fuel cells, having used them on manned space flight systems over four decades. Consequently, the NASA Glenn Research Center has initiated an effort to investigate and develop fuel cell technologies for multiple aerospace applications. Two promising fuel cell types are the proton exchange membrane (PEM) and solid oxide fuel cell (SOFC). PEM technology, first used on the Gemini spacecraft in the sixties, remained unutilized thereafter until the automotive industry recently recognized the potential. PEM fuel cells are low-temperature devices offering quick startup time but requiring relatively pure hydrogen fuel. In contrast, SOFCs operate at high temperatures and tolerate higher levels of impurities. This flexibility allows SOFCs to use hydrocarbon fuels, which is an important factor considering our current liquid petroleum infrastructure. However, depending on the specific application, either PEM or SOFC can be attractive. As only NASA can, the Agency is pursuing fuel cell technology for civil uninhabited aerial vehicles (UAVs) because it offers enhanced scientific capabilities, including enabling highaltitude, long-endurance missions. The NASA Helios aircraft demonstrated altitudes approaching 100,000 ft using solar power in 2001, and future plans include the development of a regenerative PEM fuel cell to provide nighttime power. Unique to NASA's mission, the high-altitude aircraft application requires the PEM fuel cell to operate on pure oxygen, instead of the air typical of terrestrial applications.

  17. Mixed-mode VLSI optic flow sensors for micro air vehicles

    NASA Astrophysics Data System (ADS)

    Barrows, Geoffrey Louis

    We develop practical, compact optic flow sensors. To achieve the desired weight of 1--2 grams, mixed-mode and mixed-signal VLSI techniques are used to develop compact circuits that directly perform computations necessary to measure optic flow. We discuss several implementations, including a version fully integrated in VLSI, and several "hybrid sensors" in which the front end processing is performed with an analog chip and the back end processing is performed with a microcontroller. We extensively discuss one-dimensional optic flow sensors based on the linear competitive feature tracker (LCFT) algorithm. Hardware implementations of this algorithm are shown able to measure visual motion with contrast levels on the order of several percent. We argue that the development of one-dimensional optic flow sensors is therefore reduced to a problem of engineering. We also introduce two related two-dimensional optic flow algorithms that are amenable to implementation in VLSI. This includes the planar competitive feature tracker (PCFT) algorithm and the trajectory method. These sensors are being developed to solve small-scale navigation problems in micro air vehicles, which are autonomous aircraft whose maximum dimension is on the order of 15 cm. We obtain a proof-of-principle of small-scale navigation by mounting a prototype sensor onto a toy glider and programming the sensor to control a rudder or an elevator to affect the glider's path during flight. We demonstrate the determination of altitude by measuring optic flow in the downward direction. We also demonstrate steering to avoid a collision with a wall, when the glider is tossed towards the wall at a shallow angle, by measuring the optic flow in the direction of the glider's left and right side.

  18. Bio-inspired multi-mode optic flow sensors for micro air vehicles

    NASA Astrophysics Data System (ADS)

    Park, Seokjun; Choi, Jaehyuk; Cho, Jihyun; Yoon, Euisik

    2013-06-01

    Monitoring wide-field surrounding information is essential for vision-based autonomous navigation in micro-air-vehicles (MAV). Our image-cube (iCube) module, which consists of multiple sensors that are facing different angles in 3-D space, can be applied to the wide-field of view optic flows estimation (?-Compound eyes) and to attitude control (?- Ocelli) in the Micro Autonomous Systems and Technology (MAST) platforms. In this paper, we report an analog/digital (A/D) mixed-mode optic-flow sensor, which generates both optic flows and normal images in different modes for ?- Compound eyes and ?-Ocelli applications. The sensor employs a time-stamp based optic flow algorithm which is modified from the conventional EMD (Elementary Motion Detector) algorithm to give an optimum partitioning of hardware blocks in analog and digital domains as well as adequate allocation of pixel-level, column-parallel, and chip-level signal processing. Temporal filtering, which may require huge hardware resources if implemented in digital domain, is remained in a pixel-level analog processing unit. The rest of the blocks, including feature detection and timestamp latching, are implemented using digital circuits in a column-parallel processing unit. Finally, time-stamp information is decoded into velocity from look-up tables, multiplications, and simple subtraction circuits in a chip-level processing unit, thus significantly reducing core digital processing power consumption. In the normal image mode, the sensor generates 8-b digital images using single slope ADCs in the column unit. In the optic flow mode, the sensor estimates 8-b 1-D optic flows from the integrated mixed-mode algorithm core and 2-D optic flows with an external timestamp processing, respectively.

  19. Evaluation of some significant issues affecting trajectory and control management for air-breathing hypersonic vehicles

    NASA Technical Reports Server (NTRS)

    Hattis, Philip D.; Malchow, Harvey L.

    1992-01-01

    Horizontal takeoff airbreathing-propulsion launch vehicles require near-optimal guidance and control which takes into account performance sensitivities to atmospheric characteristics while satisfying physically-derived operational constraints. A generic trajectory/control analysis tool that deepens insight into these considerations has been applied to two versions of a winged-cone vehicle model. Information that is critical to the design and trajectory of these vehicles is derived, and several unusual characteristics of the airbreathing propulsion model are shown to have potentially substantial effects on vehicle dynamics.

  20. Characterizing the spatial variation of air pollutants and the contributions of high emitting vehicles in Pittsburgh, PA.

    PubMed

    Tan, Yi; Lipsky, Eric M; Saleh, Rawad; Robinson, Allen L; Presto, Albert A

    2014-12-16

    We used a mobile measurement platform to characterize a suite of air pollutants (black carbon (BC), particle-bound polycyclic aromatic hydrocarbons (PB-PAH), benzene, and toluene) in the city of Pittsburgh and surrounding areas. More than 270 h of data were collected from forty-two sites which were selected based on analysis in the geographic information system (GIS). Mobile measurements were performed during three different times of day (mornings, afternoons/evenings, and overnight) in both winter (November 2011 to February 2012) and summer (June 2012 to August 2012). Pollutant concentrations were elevated in river valleys by 9% (benzene) to 30% (PB-PAH) relative to upland areas. Traffic had strong impacts on measured pollutants. PB-PAH and BC concentrations at high traffic sites were a factor of 2 and 30% higher than at low traffic sites, respectively. Pollutant concentrations were highest in the morning sessions due to a combination of traffic and meteorological conditions. The highly time-resolved data indicated that elevated pollutant concentrations at high traffic sites were due to short duration plume events associated with high emitting vehicles. High emitting vehicles contributed up to 70% of the near road PB-PAH and 30% of BC; emissions from these vehicles drove substantial spatial variations in BC and PB-PAH concentrations. Many high emitting vehicles were presumably diesel trucks or buses, because plumes were strongly correlated with truck traffic volume. In contrast, PB-PAH and BC in the nonplume background air was weakly correlated with traffic, and their spatial patterns were more influenced by terrain and point source emissions. The spatial variability in contributions of high emitting vehicles suggests that the effect of potential control strategies vary for different pollutants and environments. PMID:25393032

  1. An efficient fluid-structure interaction method for conceptual design of flexible micro air vehicle wings: Development, comparison, and application

    NASA Astrophysics Data System (ADS)

    Combes, Thomas P.

    This thesis summarizes the development, comparison, and applications of an efficient fluid-structure interaction method capable of simulating the effects that wing flexibility has on micro air vehicle (MAV) performance. Micro air vehicles wing designs often incorporate flexible wing structures that mimic the skeleton / membrane designs found in natural flyers such as bats and insects. However, accurate performance prediction for these wings requires the coupling of the simulation of the fluid physics around the wing and the simulation of the structural deformation. These fluid-structure interaction (FSI) simulations are often accomplished using high fidelity, computationally expensive techniques such as computational fluid dynamics (CFD) for the fluid physics and nonlinear finite element analysis (FEA) for the structural simulation. The main drawback of these methods, especially for use simulating vehicles that are able to be manufactured relatively quickly, is that the computational cost required to perform relevant trade studies on the design is prohibitively large and time-consuming. The main goal of this research is the development of a coupled fluid-structure interaction method computationally efficient and accurate enough to be used for conceptual design of micro air vehicles. An advanced potential flow model is used to calculate aerodynamic performance and loading, while a simplified finite element structural model using frame and shell elements calculates the wing deflection due to aerodynamic loading. The contents of this thesis include a literature survey of current approaches, an introduction to the efficient FSI formulation, comparison of the presented FSI method with higher-fidelity simulation methods, demonstrations of the method's capability for tradeoff and optimization studies, and an overview of contributions to a nonlinear dynamic algorithm for the simulation of flapping flight.

  2. Viking entry vehicle aerodynamics at m equals 2 in air and some preliminary test data for flight in CO2

    NASA Technical Reports Server (NTRS)

    Sammonds, R. I.; Kruse, R. L.

    1975-01-01

    The static and dynamic aerodynamic characteristics of the Viking entry vehicle were determined experimentally in free flight in air at a Mach number near 2. Preliminary results were also obtained in CO2 at M infinity = 11. The low speed tests in air confirmed a region of dynamic instability previously observed. The instability was greatest at the smallest pitch amplitudes but decreased with increasing amplitude until a limit cycle was reached at about 8 deg. The tests in CO2 indicated increased drag coefficients of 3 percent with respect to those in air. Errors in the drag coefficient of this magnitude would significantly affect the reconstruction of the Martian atmosphere during entry of the Viking spacecraft.

  3. Extracting micro air vehicles aerodynamic forces and coefficients in free flight using visual motion tracking techniques

    NASA Astrophysics Data System (ADS)

    Mettler, B. F.

    2010-09-01

    This paper describes a methodology to extract aerial vehicles’ aerodynamic characteristics from visually tracked trajectory data. The technique is being developed to study the aerodynamics of centimeter-scale aircraft and develop flight simulation models. Centimeter-scale aircraft remains a largely unstudied domain of aerodynamics, for which traditional techniques like wind tunnels and computational fluid dynamics have not yet been fully adapted and validated. The methodology takes advantage of recent progress in commercial, vision-based, motion-tracking systems. This system dispenses from on-board navigation sensors and enables indoor flight testing under controlled atmospheric conditions. Given the configuration of retro-reflective markers affixed onto the aerial vehicle, the vehicle’s six degrees-of-freedom motion can be determined in real time. Under disturbance-free conditions, the aerodynamic forces and moments can be determined from the vehicle’s inertial acceleration, and furthermore, for a fixed-wing vehicle, the aerodynamic angles can be plotted from the vehicle’s kinematics. By combining this information, we can determine the temporal evolution of the aerodynamic coefficients, as they change throughout a trajectory. An attractive feature of this technique is that trajectories are not limited to equilibrium conditions but can include non-equilibrium, maneuvering flight. Whereas in traditional wind-tunnel experiments, the operating conditions are set by the experimenter, here, the aerodynamic conditions are driven by the vehicle’s own dynamics. As a result, this methodology could be useful for characterizing the unsteady aerodynamics effects and their coupling with the aircraft flight dynamics, providing insight into aerodynamic phenomena taking place at centimeter scale flight.

  4. Design of composite plastic foams for improved cushioning

    E-print Network

    Eskew, James Oliver

    1989-01-01

    and Polyethylene Foams at 0. 5G w/ 0. 444 psi Static Load 36 37 41 16. Example of a Parallel Configuration with Polyurethane and Polyethylene Foams at 0. 5G w/ 0. 311 psi Static Load on Composite . 41 17. Single Polyurethane Foam at 0. 5G w/ 0. 156 psi... Static Load and with Additional Top Loading 43 LIST OF FIGURES (Continued) Figure 18. Example of Cushion Curves for the Series Configuration w/ 2" Polyethylene and 1" Polyurethane Foams for 24" Drop Height Page 43 19. 20. 21 22 23 24. 25...

  5. Material properties for TR-55 and silicone elastomeric cushions

    SciTech Connect

    Feng, W.W.; Albertson, S.L.; Rosinsky, R.W.

    1982-10-05

    The notation of finite elastic theory for compressible rubber-like materials is introduced. The mechanics of data reduction, needed to determine the parameters of the theory, are displayed. the material properties of TR-55 rubber and silicone rubber cushions are obtained. The constitutive relation, with the material properties, correlates all uniaxial compressive data to a high degree of accuracy. The force-deformation relations of thin sheets of TR-55 in compression have been obtained. Further studies, both theoretical and experimental, on TR-55 thin sheets are needed to determine the force-deformation relation. 11 figures.

  6. 78 FR 24373 - Approval and Promulgation of Air Quality Implementation Plans; Wisconsin; Amendments to Vehicle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-25

    ...specifications and inspection requirements. In...evaporative emission test also known as the...specifications for program test equipment that mirror...specifications and inspection requirements retaining...vehicle owner may test the vehicle. The...of any authorized inspection facility...

  7. 77 FR 75388 - Approval and Promulgation of Air Quality Implementation Plans; State of Colorado; Motor Vehicle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-20

    ...Implementation Plan (SIP) revision...Vehicle Emissions Inspection Program...IM240 emissions test will fail the...IMPLEMENTATION PLANS 0 1. The authority...Identification of plan...Vehicle Emissions Inspection Program, part...apply to those tests performed on...

  8. Simulation of fully autonomous control of unmanned air vehicles for maritime surveillance

    Microsoft Academic Search

    Luke Ng; Paul Hubbard; Siu O'Young

    2010-01-01

    As the usage of unmanned systems become more prevalent, defence departments around the world are looking for new modes of human-system interaction that increase the level of autonomy of the vehicle, while maintaining operator control and trust. Defence R&D Canada is currently engaged in a research program on the simulation of Unmanned Aerial Vehicles (UAVs) and methods to increase autonomous

  9. Structural Studies of Polymer-Cushioned Lipid Bilayers J. Majewski,* J. Y. Wong,#

    E-print Network

    Wong, Joyce

    Structural Studies of Polymer-Cushioned Lipid Bilayers J. Majewski,* J. Y. Wong,# C. K. Park,# M of California, Santa Barbara, California 93106 USA ABSTRACT The structure of softly supported polymer neutron reflectometry. The polymer cushion consisted of a thin layer of branched, cationic

  10. Inflorescences of alpine cushion plants freeze autonomously and may survive subzero temperatures by supercooling

    Microsoft Academic Search

    Jürgen Hacker; Ursula Ladinig; Johanna Wagner; Gilbert Neuner

    2011-01-01

    Freezing patterns in the high alpine cushion plants Saxifraga bryoides, Saxifraga caesia, Saxifraga moschata and Silene acaulis were studied by infrared thermography at three reproductive stages (bud, anthesis, fruit development). The single reproductive shoots of a cushion froze independently in all four species at every reproductive stage. Ice formation caused lethal damage to the respective inflorescence. After ice nucleation, which

  11. Structural Sizing of a Horizontal Take-Off Launch Vehicle with an Air Collection and Enrichment System

    NASA Technical Reports Server (NTRS)

    McCurdy, David R.; Roche, Joseph M.

    2004-01-01

    In support of NASA's Next Generation Launch Technology (NGLT) program, the Andrews Gryphon booster was studied. The Andrews Gryphon concept is a horizontal lift-off, two-stage-to-orbit, reusable launch vehicle that uses an air collection and enrichment system (ACES). The purpose of the ACES is to collect atmospheric oxygen during a subsonic flight loiter phase and cool it to cryogenic temperature, ultimately resulting in a reduced initial take-off weight To study the performance and size of an air-collection based booster, an initial airplane like shape was established as a baseline and modeled in a vehicle sizing code. The code, SIZER, contains a general series of volume, surface area, and fuel fraction relationships that tie engine and ACES performance with propellant requirements and volumetric constraints in order to establish vehicle closure for the given mission. A key element of system level weight optimization is the use of the SIZER program that provides rapid convergence and a great deal of flexibility for different tank architectures and material suites in order to study their impact on gross lift-off weight. This paper discusses important elements of the sizing code architecture followed by highlights of the baseline booster study.

  12. Testing of aircraft passenger seat cushion material, full scale. Data, volume 2

    NASA Technical Reports Server (NTRS)

    Schutter, K. J.; Gaume, J. G.; Duskin, F. E.

    1980-01-01

    Burn characteristics of presently used and proposed seat cushion materials and types of constructions were determined. Eight different seat cushion configurations were subjected to full scale burn tests. Each cushion configuration was tested twice for a total of 16 tests. Two different fire sources were used: Jet A-fuel for eight tests, and a radiant energy source with propane flame for eight tests. Data were recorded for smoke density, cushion temperatures, radiant heat flux, animal response to combustion products, rate of weight loss of test specimens, cabin temperature, and type and content of gas within the cabin. When compared to existing seat cushions, the test specimens incorporating a fire barrier and those fabricated from advanced materials, using improved construction methods, exhibited significantly greater fire resistance. Flammability comparison tests were conducted upon one fire blocking configuration and one polyimide configuration.

  13. Microbes on the Cliff: Alpine Cushion Plants Structure Bacterial and Fungal Communities

    PubMed Central

    Roy, J.; Albert, C. H.; Ibanez, S.; Saccone, P.; Zinger, L.; Choler, P.; Clément, J.-C.; Lavergne, S.; Geremia, R. A.

    2013-01-01

    Plants affect the spatial distribution of soil microorganisms, but the influence of the local abiotic context is poorly documented. We investigated the effect of a single plant species, the cushion plant Silene acaulis, on habitat conditions, and microbial community. We collected soil from inside (In) and outside (Out) of the cushions on calcareous and siliceous cliffs in the French Alps along an elevation gradient (2,000–3,000?masl). The composition of the microbial communities was assessed by Capillary-Electrophoresis Single Strand Conformation Polymorphism (CE-SSCP). Univariate and multivariate analyses were conducted to characterize the response of the microbial beta-diversity to soil parameters (total C, total N, soil water content, N-NH4+,N-NO3-, and pH). Cushions affected the microbial communities, modifying soil properties. The fungal and bacterial communities did not respond to the same abiotic factors. Outside the cushions, the bacterial communities were strongly influenced by bedrock. Inside the cushions, the bacterial communities from both types of bedrock were highly similar, due to the smaller pH differences than in open areas. By contrast, the fungal communities were equally variable inside and outside of the cushions. Outside the cushions, the fungal communities responded weakly to soil pH. Inside the cushions, the fungal communities varied strongly with bedrock and elevation as well as increases in soil nutrients and water content. Furthermore, the dissimilarities in the microbial communities between the In and Out habitats increased with increasing habitat modification and environmental stress. Our results indicate that cushions act as a selective force that counteracts the influence of the bedrock and the resource limitations on the bacterial and fungal communities by buffering soil pH and enhancing soil nutrients. Cushion plants structure microbial communities, and this effect increases in stressful, acidic and nutrient-limited environments. PMID:23543612

  14. Microbes on the cliff: alpine cushion plants structure bacterial and fungal communities.

    PubMed

    Roy, J; Albert, C H; Ibanez, S; Saccone, P; Zinger, L; Choler, P; Clément, J-C; Lavergne, S; Geremia, R A

    2013-01-01

    Plants affect the spatial distribution of soil microorganisms, but the influence of the local abiotic context is poorly documented. We investigated the effect of a single plant species, the cushion plant Silene acaulis, on habitat conditions, and microbial community. We collected soil from inside (In) and outside (Out) of the cushions on calcareous and siliceous cliffs in the French Alps along an elevation gradient (2,000-3,000?masl). The composition of the microbial communities was assessed by Capillary-Electrophoresis Single Strand Conformation Polymorphism (CE-SSCP). Univariate and multivariate analyses were conducted to characterize the response of the microbial beta-diversity to soil parameters (total C, total N, soil water content, [Formula: see text], and pH). Cushions affected the microbial communities, modifying soil properties. The fungal and bacterial communities did not respond to the same abiotic factors. Outside the cushions, the bacterial communities were strongly influenced by bedrock. Inside the cushions, the bacterial communities from both types of bedrock were highly similar, due to the smaller pH differences than in open areas. By contrast, the fungal communities were equally variable inside and outside of the cushions. Outside the cushions, the fungal communities responded weakly to soil pH. Inside the cushions, the fungal communities varied strongly with bedrock and elevation as well as increases in soil nutrients and water content. Furthermore, the dissimilarities in the microbial communities between the In and Out habitats increased with increasing habitat modification and environmental stress. Our results indicate that cushions act as a selective force that counteracts the influence of the bedrock and the resource limitations on the bacterial and fungal communities by buffering soil pH and enhancing soil nutrients. Cushion plants structure microbial communities, and this effect increases in stressful, acidic and nutrient-limited environments. PMID:23543612

  15. Double Cushions Preserve Transmembrane Protein Mobility in Supported Bilayer Systems

    PubMed Central

    Diaz, Arnaldo J.; Albertorio, Fernando; Daniel, Susan; Cremer, Paul S.

    2012-01-01

    Supported lipid bilayers (SLBs) have been widely used as model systems to study cell membrane processes because they preserve the same 2D membrane fluidity found in living cells. One of the most significant limitations of this platform, however, is its inability to incorporate mobile transmembrane species. It is often postulated that transmembrane proteins reconstituted in SLBs lose their mobility because of direct interactions between the protein and the underlying substrate. Herein, we demonstrate a highly mobile fraction for a transmembrane protein, annexin V. Our strategy involves supporting the lipid bilayer on a double cushion, where we not only create a large space to accommodate the transmembrane portion of the macromolecule but also passivate the underlying substrate to reduce nonspecific protein–substrate interactions. The thickness of the confined water layer can be tuned by fusing vesicles containing polyethyleneglycol (PEG)-conjugated lipids of various molecular weights to a glass substrate that has first been passivated with a sacrificial layer of bovine serum albumin (BSA). The 2D fluidity of these systems was characterized by fluorescence recovery after photobleaching (FRAP) measurements. Uniform, mobile phospholipid bilayers with lipid diffusion coefficients of around 3 × 10?8 cm2/s and percent mobile fractions of over 95% were obtained. Moreover, we obtained annexin V diffusion coefficients that were also around 3 × 10?8 cm2/s with mobile fractions of up to 75%. This represents a significant improvement over bilayer platforms fabricated directly on glass or using single cushion strategies. PMID:18510376

  16. Long-term trends in nitrogen oxide emissions from motor vehicles at national, state, and air basin scales

    NASA Astrophysics Data System (ADS)

    McDonald, Brian C.; Dallmann, Timothy R.; Martin, Elliot W.; Harley, Robert A.

    2012-09-01

    A fuel-based approach is used to estimate nitrogen oxides (NOx = NO + NO2) emissions from gasoline- and diesel-powered motor vehicles. Estimates are made at the national level for the period 1990-2010. Vehicle emissions are also estimated at the state level for California, and for the South Coast (Los Angeles) and San Joaquin Valley air basins. Fuel-based emission estimates are compared with predictions from widely used emission inventory models. Changes in diesel NOxemissions vary over time: increasing between 1990 and 1997, stable between 1997 and 2007, and decreasing since 2007. In contrast, gasoline engine-related NOxemissions have decreased steadily, by ˜65% overall between 1990 and 2010, except in the San Joaquin Valley, where reductions were not as large due to faster population growth. In the San Joaquin Valley, diesel engines were the dominant on-road NOxsource in all years considered (reaching ˜70% in 2010). In the urbanized South Coast air basin, gasoline engine emissions dominated in the past and have been comparable to on-road diesel sources since 2007 (down from ˜75% in 1990). Other major anthropogenic sources of NOxare added to compare emission trends with trends in surface pollutant observations and satellite-derived data. When all major anthropogenic NOx sources are included, the overall emission trend is downward in all cases (-45% to -60%). Future reductions in motor vehicle NOxwill depend on the effectiveness of new exhaust after-treatment controls on heavy-duty trucks, as well as further improvements todurabilityof emission control systems on light-duty vehicles.

  17. 78 FR 11122 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Motor Vehicle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-15

    ...Motor Vehicle Emission Simulator model (MOVES). Those counties are...most recent version of the MOVES model. On January 29, 2013, Pennsylvania...the Highway Mobile Source Emission Factor Model (MOBILE6.2). On March 2,...

  18. 78 FR 68378 - Approval and Promulgation of Air Quality Implementation Plans; Illinois; Amendments to Vehicle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-14

    ...equipment specifications and inspection requirements retaining...for OBD testing. All test stations, whether they...required to use the same test equipment and data management...Requirements for the entire test system and vehicle inspection report are...

  19. Maglev vehicles and superconductor technology: Integration of high-speed ground transportation into the air travel system

    SciTech Connect

    Johnson, L.R.; Rote, D.M.; Hull, J.R.; Coffey, H.T.; Daley, J.G.; Giese, R.F.

    1989-04-01

    This study was undertaken to (1) evaluate the potential contribution of high-temperature superconductors (HTSCs) to the technical and economic feasibility of magnetically levitated (maglev) vehicles, (2) determine the status of maglev transportation research in the United States and abroad, (3) identify the likelihood of a significant transportation market for high-speed maglev vehicles, and (4) provide a preliminary assessment of the potential energy and economic benefits of maglev systems. HTSCs should be considered as an enhancing, rather than an enabling, development for maglev transportation because they should improve reliability and reduce energy and maintenance costs. Superconducting maglev transportation technologies were developed in the United States in the late 1960s and early 1970s. Federal support was withdrawn in 1975, but major maglev transportation programs were continued in Japan and West Germany, where full-scale prototypes now carry passengers at speeds of 250 mi/h in demonstration runs. Maglev systems are generally viewed as very-high-speed train systems, but this study shows that the potential market for maglev technology as a train system, e.g., from one downtown to another, is limited. Rather, aircraft and maglev vehicles should be seen as complementing rather than competing transportation systems. If maglev systems were integrated into major hub airport operations, they could become economical in many relatively high-density US corridors. Air traffic congestion and associated noise and pollutant emissions around airports would also be reduced. 68 refs., 26 figs., 16 tabs.

  20. The design of passively athermalized narrow- and wide-field-of-view infrared objectives for the OBSERVER unmanned air vehicle

    NASA Astrophysics Data System (ADS)

    Simmons, Richard C.; Manning, Paul A.; Chamberlain, Trevor V.

    2004-12-01

    Some years ago QinetiQ introduced a short-range reconnaissance unmanned air vehicle (UAV), known as OBSERVER, which carried a visible three-camera sensor. To increase its versatility, a compatible infrared (IR) thermal imaging (TI) sensor was developed for the vehicle for operation in the 8-12mm waveband with a dual field of view function. The sensor incorporates a specially designed camera board, employing two IR lead scandium tantalate (PST) detectors based on UK un-cooled TI technology. Since no cooling engine is required for the detectors, the sensor module is very lightweight and hence well suited to its UAV application. So as to achieve the minimum possible payload for the vehicle, in addition to the lightweight detectors and electronics board, compact low mass optical solutions were devised for the camera objectives. These functioned at a relative aperture of f/1.0 and were designed to provide stable focus and imaging performance over a comparatively large temperature span (-10°C to + 50°C) to enable all weather operation. In order to achieve an athermalisation scheme devoid of elaborate electro-mechanical drives, thermally passive solutions were developed for the objectives in which the differing thermal characteristics of the components were designed to self-cancel optically. In this paper, the design and performance limitations of the optics are discussed and the procedure employed for establishing a thin lens pre-design for one of the objectives is described.

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

    PubMed

    Zbikowski, Rafa?

    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 on the trailing edge and including the influence of the vortical structure on the leading edge. Mathematically, two analytic approaches are proposed. The first derives all the quantities of interest from the notion of circulation and leads to tractable integral equations. This is an application of the von Kármán-Sears unsteady wing theory and its nonlinear extensions due to McCune and Tavares; the latter can account for the bound leading-edge vortex and wake distortion. The second approach uses the velocity potential as the central concept and leads to relatively simple ordinary differential equations. It is a combination of two techniques: (i) unsteady aerodynamic modelling of attached flow on helicopter rotor blades; and (ii) Polhamus's leading-edge suction analogy. The first of these involves both frequency-domain (Theodorsen style) and time-domain (indicial) methods, including the effects of wing sweeping and returning wake. The second is a nonlinear correction accounting for the bound leading-edge vortex. Connections of the proposed framework with control engineering and aeroelasticity are pointed out. PMID:16210181

  2. Hover and wind-tunnel testing of shrouded rotors for improved micro air vehicle design

    NASA Astrophysics Data System (ADS)

    Pereira, Jason L.

    The shrouded-rotor configuration has emerged as the most popular choice for rotary-wing Micro Air Vehicles (MAVs), because of the inherent safety of the design and the potential for significant performance improvements. However, traditional design philosophies based on experience with large-scale ducted propellers may not apply to the low-Reynolds-number (˜20,000) regime in which MAVs operate. An experimental investigation of the effects of varying the shroud profile shape on the performance of MAV-scale shrouded rotors has therefore been conducted. Hover tests were performed on seventeen models with a nominal rotor diameter of 16 cm (6.3 in) and various values of diffuser expansion angle, diffuser length, inlet lip radius and blade tip clearance, at various rotor collective angles. Compared to the baseline open rotor, the shrouded rotors showed increases in thrust by up to 94%, at the same power consumption, or reductions in power by up to 62% at the same thrust. These improvements surpass those predicted by momentum theory, due to the additional effect of the shrouds in reducing the non-ideal power losses of the rotor. Increasing the lip radius and decreasing the blade tip clearance caused performance to improve, while optimal values of diffuser angle and length were found to be 10 and 50% of the shroud throat diameter, respectively. With the exception of the lip radius, the effects of changing any of the shrouded-rotor parameters on performance became more pronounced as the values of the other parameters were changed to degrade performance. Measurements were also made of the wake velocity profiles and the shroud surface pressure distributions. The uniformity of the wake was improved by the presence of the shrouds and by decreasing the blade tip clearance, resulting in lower induced power losses. For high net shroud thrust, a favorable pressure distribution over the inlet was seen to be more important than in the diffuser. Strong suction pressures were observed above the blade-passage region on the inlet surface; taking advantage of this phenomenon could enable further increases in thrust. However, trade studies showed that, for a given overall aircraft size limitation, and ignoring considerations of the safety benefits of a shroud, a larger-diameter open rotor is more likely to give better performance than a smaller-diameter shrouded rotor. The open rotor and a single shrouded-rotor model were subsequently tested at a single collective in translational flight, at angles of attack from 0° (axial flow) to 90° (edgewise flow), and at various advance ratios. In axial flow, the net thrust and the power consumption of the shrouded rotor were lower than those of the open rotor. In edgewise flow, the shrouded rotor produced greater thrust than the open rotor, while consuming less power. Measurements of the shroud surface pressure distributions illustrated the extreme longitudinal asymmetry of the flow around the shroud, with consequent pitch moments much greater than those exerted on the open rotor. Except at low airspeeds and high angles of attack, the static pressure in the wake did not reach ambient atmospheric values at the diffuser exit plane; this challenges the validity of the fundamental assumption of the simple-momentum-theory flow model for short-chord shrouds in translational flight.

  3. Peripherally inserted central catheter cushioning: ?a pilot study comparing gauze with silicone foam.

    PubMed

    Curtis, Kerrie; Ockerby, Cherene; Bennett, Paul; Heywood, Ellen; Marshall, Linda

    2015-06-01

    Healthcare providers in the authors' healthcare organization, which includes five public hospitals and other healthcare services, use gauze as a cushioning material under the transparent semipermeable dressing (TSM) for peripherally inserted central catheters (PICCs) for patients receiving chemotherapy. When dressings are changed on a weekly basis, patients often present with dressings that are loose, as well as with evidence of irritation and perspiration under the cushioning gauze. In addition, leaving gauze dressings in place for a week contradicts national and international recommendations. Therefore, an alternative cushioning material was piloted that would be more comfortable for patients and consistent with evidence-based guidelines.?. PMID:26000574

  4. Distinctive features of the flow past high-speed flight vehicles with air-breathing engines on subsonic, transonic, and low supersonic velocity ranges

    Microsoft Academic Search

    N. A. Blagoveshchenskii; V. N. Gusev; S. M. Zadonskii

    2007-01-01

    The aerodynamic characteristics and distinctive features of the flow past hypersonic integral-layout flight vehicles with\\u000a air-breathing engines intended for cruise flight in the atmosphere are experimentally investigated. The experiments were conducted\\u000a on a simplified model designed with regard for the general principles of integration of vehicles of the class considered.\\u000a The tests were performed in a wind tunnel over the

  5. The cost of crop damage caused by ozone air pollution from motor vehicles

    Microsoft Academic Search

    James Murphy; Mark Delucchi; Donald McCubbin; H. J. Kim

    1999-01-01

    The effects of ozone air pollution on the agricultural sector are an important environmental challenge facing policy makers. Most studies of the economic impact of air pollution on agriculture have found that a 25% reduction in ambient ozone would provide benefits of at least $1–2 billion annually in the United States. This paper extends existing research by estimating the benefits

  6. Adaptive neuro-fuzzy inference system based autonomous flight control of unmanned air vehicles

    Microsoft Academic Search

    Sefer Kurnaz; Omer Cetin; Okyay Kaynak

    2010-01-01

    In this paper, an ANFIS (adaptive neuro-fuzzy inference system) based autonomous flight controller for UAVs (unmanned aerial vehicles) is described. To control the position of the UAV in three dimensional space as altitude and longitude–latitude location, three fuzzy logic modules are developed. These adjust the pitch angle, the roll angle and the throttle position of the UAV so that its

  7. Some factors affecting the use of lighter than air systems. [economic and performance estimates for dirigibles and semi-buoyant hybrid vehicles

    NASA Technical Reports Server (NTRS)

    Havill, C. D.

    1974-01-01

    The uses of lighter-than-air vehicles are examined in the present day transportation environment. Conventional dirigibles were found to indicate an undesirable economic risk due to their low speeds and to uncertainties concerning their operational use. Semi-buoyant hybrid vehicles are suggested as an alternative which does not have many of the inferior characteristics of conventional dirigibles. Economic and performance estimates for hybrid vehicles indicate that they are competitive with other transportation systems in many applications, and unique in their ability to perform some highly desirable emergency missions.

  8. Assessment of the capacity of vehicle cabin air inlet filters to reduce diesel exhaust-induced symptoms in human volunteers

    PubMed Central

    2014-01-01

    Background Exposure to particulate matter (PM) air pollution especially derived from traffic is associated with increases in cardiorespiratory morbidity and mortality. In this study, we evaluated the ability of novel vehicle cabin air inlet filters to reduce diesel exhaust (DE)-induced symptoms and markers of inflammation in human subjects. Methods Thirty healthy subjects participated in a randomized double-blind controlled crossover study where they were exposed to filtered air, unfiltered DE and DE filtered through two selected particle filters, one with and one without active charcoal. Exposures lasted for one hour. Symptoms were assessed before and during exposures and lung function was measured before and after each exposure, with inflammation assessed in peripheral blood five hours after exposures. In parallel, PM were collected from unfiltered and filtered DE and assessed for their capacity to drive damaging oxidation reactions in a cell-free model, or promote inflammation in A549 cells. Results The standard particle filter employed in this study reduced PM10 mass concentrations within the exposure chamber by 46%, further reduced to 74% by the inclusion of an active charcoal component. In addition use of the active charcoal filter was associated by a 75% and 50% reduction in NO2 and hydrocarbon concentrations, respectively. As expected, subjects reported more subjective symptoms after exposure to unfiltered DE compared to filtered air, which was significantly reduced by the filter with an active charcoal component. There were no significant changes in lung function after exposures. Similarly diesel exhaust did not elicit significant increases in any of the inflammatory markers examined in the peripheral blood samples 5 hour post-exposure. Whilst the filters reduced chamber particle concentrations, the oxidative activity of the particles themselves, did not change following filtration with either filter. In contrast, diesel exhaust PM passed through the active charcoal combination filter appeared less inflammatory to A549 cells. Conclusions A cabin air inlet particle filter including an active charcoal component was highly effective in reducing both DE particulate and gaseous components, with reduced exhaust-induced symptoms in healthy volunteers. These data demonstrate the effectiveness of cabin filters to protect subjects travelling in vehicles from diesel exhaust emissions. PMID:24621126

  9. DIFFERENCES IN AIR BAG PERFORMANCE WITH CHILDREN IN VARIOUS RESTRAINT CONFIGURATIONS AND VEHICLE TYPES

    Microsoft Academic Search

    Rajiv A. Menon; Kristy B. Arbogast; John Cooper; Stephen A. Ridella; Mohannad Murad; Richard Barnes; Michael J. Kallan; Flaura K. Winston

    Previous studies have identified a fatality risk for children exposed to air bags, particularly in the presence of non-restraint or inadequate restraint of the child and pre-impact braking, conditions that place the child out-of-position. Consequently, many manufacturers are opting to suppress the air bag when an out-of-position child, particularly one who is unrestrained, is detected. This study provides current estimates

  10. Effects of conventional and alternating cushion weight-shifting in persons with spinal cord injury

    PubMed Central

    Wu, Gary A.; Bogie, Kath M.

    2015-01-01

    A repeated-measures study of 13 adult full-time wheelchair users with spinal cord injury (SCI) was carried out to determine whether alternating-pressure air cushion (APAC) use compared with independent pressure relief (IPR) provides reliable, effective pressure relief for individuals with SCI. Bilateral mean ischial interface pressure (IP), transcutaneous oxygen tension (TcPO2), and unilateral laser Doppler blood flow were evaluated. Blood flow component contributions were determined using short-time Fourier transform (STFT)-based spectral analysis. IPR assessment was carried out at recruitment. Study participants then used an APAC for 2 wk every 3 mo for 18 mo. IPR weight-shifting decreased mean ischial IP (p < 0.05) and increased mean TcPO2 (p < 0.05). All variables rapidly returned to preintervention levels following weight-shifting except for the cardiac component of blood flow. APAC-induced weight-shifting decreased mean ischial IP (p < 0.05). Mean TcPO2 increased and was higher than for IPR. STFT analysis indicated that quiet sitting following APAC-induced weight-shifting produced a higher neurogenic component of blood flow than following IPR (p = 0.02). Thus, IPR positively affects multiple aspects of tissue health but produces transient improvements and must be repeated regularly. APAC activation dynamically and continuously alters IP distribution with more sustained positive tissue health effects. PMID:25629607

  11. Frzb modulates Wnt9a-mediated ?-catenin signaling during avian atrioventricular cardiac cushion development

    Microsoft Academic Search

    Anthony D. Person; Robert J. Garriock; Paul A. Krieg; Raymond B. Runyan; Scott E. Klewer

    2005-01-01

    Normal development of the cardiac atrioventricular (AV) endocardial cushions is essential for proper ventricular septation and morphogenesis of the mature mitral and tricuspid valves. In this study, we demonstrate spatially restricted expression of both Wnt-9a (formerly Wnt-14) and the secreted Wnt antagonist Frzb in AV endocardial cushions of the developing chicken heart. Wnt-9a expression is detected only in AV canal

  12. A Small SemiAutonomous Rotary-Wing Unmanned Air Vehicle (UAV)

    Microsoft Academic Search

    Scott D. Hanford; Lyle N. Long; Joseph F. Horn

    2005-01-01

    Small radio controlled (R\\/C) rotary-wing UAVs have many potential military and civilian applications, but can be very difficult to fly. Small and lightweight sensors and computers can be used to implement a control system to make these vehicles easier to fly. To develop a control system for a small UAV, an 8-bit microcontroller has been interfaced with MEMS (Micro-Electro-Mechanical Systems)

  13. DPPG Liposomes Adsorbed on Polymer Cushions: Effect of Roughness on Amount, Surface Composition and Topography.

    PubMed

    Duarte, Andreia A; Botelho do Rego, Ana M; Salerno, Marco; Ribeiro, Paulo A; El Bari, Nezha; Bouchikhi, Benachir; Raposo, Maria

    2015-07-01

    The adsorption of intact liposomes onto solid supports is a fundamental issue when preparing systems with encapsulated biological molecules. In this work, the adsorption kinetic of 1,2-dipalmitoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (sodium salt) liposomes onto cushions prepared from commom polyelectrolytes by the layer-by-layer technique was investigated with the main objective of finding the surface conditions leading to the adsorption of intact liposomes. For this purpose, different cushion surface roughnesses were obtained by changing the number of cushion bilayers. The adsorbed amount per unit area was measured through quartz crystal microbalance, surface morphology was characterized by atomic force microscopy, and the surface composition was assessed by X-ray photoelectron spectroscopy. The results show that (1) the amount of adsorbed lipids depends on the number of cushion bilayers, (2) the cushions are uniformly covered by the adsorbed lipids, and (3) the surface morphology of polymer cushions tunes liposome rupture and its adsorption kinetics. The fraction of ruptured liposomes, calculated from the measured amount of adsorbed lipids, is a function of surface roughness together with other surface morphology parameters, namely the dominating in-plane spatial feature size, the fractal dimension, and other textural features as well as amplitude and hybrid parameters. PMID:26076391

  14. Mixed-mode VLSI optic flow sensors for in-flight control of a micro air vehicle

    NASA Astrophysics Data System (ADS)

    Barrows, Geoffrey L.; Neely, C.

    2000-11-01

    NRL is developing compact optic flow sensors for use in a variety of small-scale navigation and collision avoidance tasks. These sensors are being developed for use in micro air vehicles (MAVs), which are autonomous aircraft whose maximum dimension is on the order of 15 cm. To achieve desired weight specifications of 1 - 2 grams, mixed-signal VLSI circuitry is being used to develop compact focal plane sensors that directly compute optic flow. As an interim proof of principle, we have constructed a sensor comprising a focal plane sensor head with on-chip processing and a back-end PIC microcontroller. This interim sensors weighs approximately 25 grams and is able to measure optic flow with real-world and low-contrast textures. Variations of this sensor have been used to control the flight of a glider in real-time to avoid collisions with walls.

  15. On the Application of Rapid Prototyping Technology for the Fabrication of Flapping Wings for Micro Air Vehicles

    NASA Astrophysics Data System (ADS)

    Kraemer, Kurtis Leigh

    Micro air vehicles (MAV) are a class of small uninhabited aircraft with dimensions less than 15 cm (6 in) and mass less than 500g (1.1 lbs). The aim of this research was to develop a fast, accurate, low-cost, and repeatable fabrication process for flapping MAV wings. Through the use of the RepRap Mendel open-source fused-deposition modeling (FDM) rapid prototyping machine ("3-D printer"), various wing prototypes were designed and fabricated using a bio-inspired approach. Testing of the aerodynamic performance of both real locust wings and the 3-D printed wing prototypes was performed through axial spin testing. Bending stiffness measurements were also performed on the 3-D printed wings. Through the use of open-source rapid prototyping technology, a fast and low-cost fabrication process for flapping MAV wings has been developed, out of which further understanding of flapping wing design and fabrication has been gained.

  16. A Common Communications, Navigation and Surveillance Infrastructure for Accommodating Space Vehicles in the Next Generation Air Transportation System

    NASA Technical Reports Server (NTRS)

    VanSuetendael, RIchard; Hayes, Alan; Birr, Richard

    2008-01-01

    Suborbital space flight and space tourism are new potential markets that could significantly impact the National Airspace System (NAS). Numerous private companies are developing space flight capabilities to capture a piece of an emerging commercial space transportation market. These entrepreneurs share a common vision that sees commercial space flight as a profitable venture. Additionally, U.S. space exploration policy and national defense will impose significant additional demands on the NAS. Air traffic service providers must allow all users fair access to limited airspace, while ensuring that the highest levels of safety, security, and efficiency are maintained. The FAA's Next Generation Air Transportation System (NextGen) will need to accommodate spacecraft transitioning to and from space through the NAS. To accomplish this, space and air traffic operations will need to be seamlessly integrated under some common communications, navigation and surveillance (CNS) infrastructure. As part of NextGen, the FAA has been developing the Automatic Dependent Surveillance Broadcast (ADS-B) which utilizes the Global Positioning System (GPS) to track and separate aircraft. Another key component of NextGen, System-Wide Information Management/ Network Enabled Operations (SWIM/NEO), is an open architecture network that will provide NAS data to various customers, system tools and applications. NASA and DoD are currently developing a space-based range (SBR) concept that also utilizes GPS, communications satellites and other CNS assets. The future SBR will have very similar utility for space operations as ADS-B and SWIM has for air traffic. Perhaps the FAA, NASA, and DoD should consider developing a common space-based CNS infrastructure to support both aviation and space transportation operations. This paper suggests specific areas of research for developing a CNS infrastructure that can accommodate spacecraft and other new types of vehicles as an integrated part of NextGen.

  17. Remote Sensing of Arctic Environmental Conditions and Critical Infrastructure using Infra-Red (IR) Cameras and Unmanned Air Vehicles (UAVs)

    NASA Astrophysics Data System (ADS)

    Hatfield, M. C.; Webley, P.; Saiet, E., II

    2014-12-01

    Remote Sensing of Arctic Environmental Conditions and Critical Infrastructure using Infra-Red (IR) Cameras and Unmanned Air Vehicles (UAVs) Numerous scientific and logistical applications exist in Alaska and other arctic regions requiring analysis of expansive, remote areas in the near infrared (NIR) and thermal infrared (TIR) bands. These include characterization of wild land fire plumes and volcanic ejecta, detailed mapping of lava flows, and inspection of lengthy segments of critical infrastructure, such as the Alaska pipeline and railroad system. Obtaining timely, repeatable, calibrated measurements of these extensive features and infrastructure networks requires localized, taskable assets such as UAVs. The Alaska Center for Unmanned Aircraft Systems Integration (ACUASI) provides practical solutions to these problem sets by pairing various IR sensors with a combination of fixed-wing and multi-rotor air vehicles. Fixed-wing assets, such as the Insitu ScanEagle, offer long reach and extended duration capabilities to quickly access remote locations and provide enduring surveillance of the target of interest. Rotary-wing assets, such as the Aeryon Scout or the ACUASI-built Ptarmigan hexcopter, provide a precision capability for detailed horizontal mapping or vertical stratification of atmospheric phenomena. When included with other ground capabilities, we will show how they can assist in decision support and hazard assessment as well as giving those in emergency management a new ability to increase knowledge of the event at hand while reducing the risk to all involved. Here, in this presentation, we illustrate how UAV's can provide the ideal tool to map and analyze the hazardous events and critical infrastructure under extreme environmental conditions.

  18. To cite this document: Itasse, Maxime and Moschetta, Jean-Marc Hybrid micro air vehicle for complex environment missions. In: Workshop Micro-Drones du

    E-print Network

    Mailhes, Corinne

    environment missions. In: Workshop Micro-Drones du Micro Air Vehicle Research Center, 27 Jan 2012, Toulouse aspect ratio. (a) MAVion (b) Roll & Fly Figure 1: The MAVion, a tandem-rotor tilt-body Experimental fan was implemented along with a series of honeycomb grids and screens to split and damp vertical

  19. Decentralized stabilization and collision avoidance of multiple air vehicles with limited sensing capabilities

    Microsoft Academic Search

    Dimos V. Dimarogonas; Kostas J. Kyriakopoulos

    2005-01-01

    Motivated by the needs of distributed air traffic management, we extend the decentralized navigation function methodology, established in previous work for navigation of multiple holonomic agents with global sensing capabilities to the case of local sensing capabilities. Each agent plans its actions without knowing (i) the destinations of the others and (ii) the positions of agents outside its sensing neighborhood.

  20. VSL analysis of hypersonic flows around a reentry vehicle with equilibrium air chemistry

    Microsoft Academic Search

    Yoshitaka Sakamura; Michio Nishida

    1992-01-01

    In the present work, the viscous shock layer (VSL) equations coupled with a rapid code for the computation of equilibrium composition of air are numerically solved for the conditions of atmospheric entry at the altitudes of 40 km, 50 km, and 60 km, and then the effects of the flight altitude, the flight Mach number and the nose radius of

  1. Trends in on-road vehicle emissions and ambient air quality in Atlanta, Georgia, USA, from the late 1990s through 2009

    PubMed Central

    Vijayaraghavan, Krish; DenBleyker, Allison; Ma, Lan; Lindhjem, Chris; Yarwood, Greg

    2014-01-01

    On-road vehicle emissions of carbon monoxide (CO), nitrogen oxides (NOx), and volatile organic compounds (VOCs) during 1995–2009 in the Atlanta Metropolitan Statistical Area were estimated using the Motor Vehicle Emission Simulator (MOVES) model and data from the National Emissions Inventories and the State of Georgia. Statistically significant downward trends (computed using the nonparametric Theil-Sen method) in annual on-road CO, NOx, and VOC emissions of 6.1%, 3.3%, and 6.0% per year, respectively, are noted during the 1995–2009 period despite an increase in total vehicle distance traveled. The CO and NOx emission trends are correlated with statistically significant downward trends in ambient air concentrations of CO and NOx in Atlanta ranging from 8.0% to 11.8% per year and from 5.8% to 8.7% per year, respectively, during similar time periods. Weather-adjusted summertime ozone concentrations in Atlanta exhibited a statistically significant declining trend of 2.3% per year during 2001– 2009. Although this trend coexists with the declining trends in on-road NOx, VOC, and CO emissions, identifying the cause of the downward trend in ozone is complicated by reductions in multiple precursors from different source sectors. Implications: Large reductions in on-road vehicle emissions of CO and NOx in Atlanta from the late 1990s to 2009, despite an increase in total vehicle distance traveled, contributed to a significant improvement in air quality through decreases in ambient air concentrations of CO and NOx during this time period. Emissions reductions in motor vehicles and other source sectors resulted in these improvements and the observed declining trend in ozone concentrations over the past decade. Although these historical trends cannot be extrapolated to the future because pollutant concentration contributions due to on-road vehicle emissions will likely become an increasingly smaller fraction of the atmospheric total, they provide an indication of the benefits of past control measures. PMID:25122954

  2. The best for the guest: high Andean nurse cushions of Azorella madreporica enhance arbuscular mycorrhizal status in associated plant species.

    PubMed

    Casanova-Katny, M Angélica; Torres-Mellado, Gustavo Adolfo; Palfner, Goetz; Cavieres, Lohengrin A

    2011-10-01

    Positive interactions between cushion plant and associated plants species in the high Andes of central Chile should also include the effects of fungal root symbionts. We hypothesized that higher colonization by arbuscular mycorrhizal (AM) fungi exists in cushion-associated (nursling) plants compared with conspecific individuals growing on bare ground. We assessed the AM status of Andean plants at two sites at different altitudes (3,200 and 3,600 ma.s.l.) in 23 species, particularly in cushions of Azorella madreporica and five associated plants; additionally, AM fungal spores were retrieved from soil outside and beneath cushions. 18 of the 23 examined plant species presented diagnostic structures of arbuscular mycorrhiza; most of them were also colonized by dark-septate endophytes. Mycorrhization of A. madreporica cushions showed differences between both sites (68% and 32%, respectively). In the native species Hordeum comosum, Nastanthus agglomeratus, and Phacelia secunda associated to A. madreporica, mycorrhization was six times higher than in the same species growing dispersed on bare ground at 3,600 ma.s.l., but mycorrhiza development was less cushion dependent in the alien plants Cerastium arvense and Taraxacum officinale at both sites. The ratio of AM fungal spores beneath versus outside cushions was also 6:1. The common and abundant presence of AM in cushion communities at high altitudes emphasizes the importance of the fungal root symbionts in such situations where plant species benefit from the microclimatic conditions generated by the cushion and also from well-developed mycorrhizal networks. PMID:21384201

  3. Implementation of the Rauch-Tung-Striebel smoother for sensor compatibility correction of a fixed-wing unmanned air vehicle.

    PubMed

    Chan, Woei-Leong; Hsiao, Fei-Bin

    2011-01-01

    This paper presents a complete procedure for sensor compatibility correction of a fixed-wing Unmanned Air Vehicle (UAV). The sensors consist of a differential air pressure transducer for airspeed measurement, two airdata vanes installed on an airdata probe for angle of attack (AoA) and angle of sideslip (AoS) measurement, and an Attitude and Heading Reference System (AHRS) that provides attitude angles, angular rates, and acceleration. The procedure is mainly based on a two pass algorithm called the Rauch-Tung-Striebel (RTS) smoother, which consists of a forward pass Extended Kalman Filter (EKF) and a backward recursion smoother. On top of that, this paper proposes the implementation of the Wiener Type Filter prior to the RTS in order to avoid the complicated process noise covariance matrix estimation. Furthermore, an easy to implement airdata measurement noise variance estimation method is introduced. The method estimates the airdata and subsequently the noise variances using the ground speed and ascent rate provided by the Global Positioning System (GPS). It incorporates the idea of data regionality by assuming that some sort of statistical relation exists between nearby data points. Root mean square deviation (RMSD) is being employed to justify the sensor compatibility. The result shows that the presented procedure is easy to implement and it improves the UAV sensor data compatibility significantly. PMID:22163819

  4. Implementation of the Rauch-Tung-Striebel Smoother for Sensor Compatibility Correction of a Fixed-Wing Unmanned Air Vehicle

    PubMed Central

    Chan, Woei-Leong; Hsiao, Fei-Bin

    2011-01-01

    This paper presents a complete procedure for sensor compatibility correction of a fixed-wing Unmanned Air Vehicle (UAV). The sensors consist of a differential air pressure transducer for airspeed measurement, two airdata vanes installed on an airdata probe for angle of attack (AoA) and angle of sideslip (AoS) measurement, and an Attitude and Heading Reference System (AHRS) that provides attitude angles, angular rates, and acceleration. The procedure is mainly based on a two pass algorithm called the Rauch-Tung-Striebel (RTS) smoother, which consists of a forward pass Extended Kalman Filter (EKF) and a backward recursion smoother. On top of that, this paper proposes the implementation of the Wiener Type Filter prior to the RTS in order to avoid the complicated process noise covariance matrix estimation. Furthermore, an easy to implement airdata measurement noise variance estimation method is introduced. The method estimates the airdata and subsequently the noise variances using the ground speed and ascent rate provided by the Global Positioning System (GPS). It incorporates the idea of data regionality by assuming that some sort of statistical relation exists between nearby data points. Root mean square deviation (RMSD) is being employed to justify the sensor compatibility. The result shows that the presented procedure is easy to implement and it improves the UAV sensor data compatibility significantly. PMID:22163819

  5. Vehicle emissions

    NSDL National Science Digital Library

    Iowa Public Television. Explore More Project

    2004-01-01

    Air pollution in the United States is a major problem; transportation plays a major role in air pollution. This informational piece, part of a series about the future of energy, provides students with data on pollution caused by vehicles. Pollutants covered include carbon monoxide, nitrogen oxide, sulfur dioxide, and lead, among others. Copyright 2005 Eisenhower National Clearinghouse

  6. VSL analysis of hypersonic flows around a reentry vehicle with equilibrium air chemistry

    NASA Astrophysics Data System (ADS)

    Sakamura, Yoshitaka; Nishida, Michio

    In the present work, the viscous shock layer (VSL) equations coupled with a rapid code for the computation of equilibrium composition of air are numerically solved for the conditions of atmospheric entry at the altitudes of 40 km, 50 km, and 60 km, and then the effects of the flight altitude, the flight Mach number and the nose radius of a reentry body on the aerodynamic heating in equilibrium air flows are examined. The results show that the calculated wall temperature increases as the altitude becomes lower, and also increases almost linearly with the flight Mach numbers (M(sub infinity) = 15 to 25). The wall heat flux at the stagnation point varies approximately with the inverse of the square root of the nose radius, and is essentially all convective, as predicted by the classic boundary layer analysis.

  7. Lithium requirements for electric vehicles using lithium-water-air batteries

    Microsoft Academic Search

    J. F. Cooper; I. Y. Borg; L. G. Oconnell; E. Behrin; B. Rubin; H. Wiesner

    1975-01-01

    In the electrochemical reaction involved in the lithium-water-air battery lithium, oxygen, and CO2 are combined; Li2CO3 is left as a by product to be removed from the battery and recycled. A subcompact car weighing 910 kg would transform 7.2 kg of lithium in traveling 320 km at 97 km\\/hr. At least an equal amount of lithium per car would be

  8. Lithium requirements for electric vehicles using lithium-water-air batteries. [Mechanically rechargeable

    Microsoft Academic Search

    J. F. Cooper; I. Y. Borg; OConnell; E. L. G. Behrin; B. Rubin; H. Wiesner

    1975-01-01

    The lithium--water--air battery is a new primary battery of such exceptional power and energy that it is a candidate to provide propulsion for electric automobiles of the future. In the electrochemical reaction involved, lithium, oxygen, and CO are combined; LiCO is left as a by-product to be removed from the battery and recycled. A subcompact car weighing 910 kg would

  9. Visual Servoing of Quadrotor Micro-Air Vehicle Using Color-Based Tracking Algorithm

    NASA Astrophysics Data System (ADS)

    Azrad, Syaril; Kendoul, Farid; Nonami, Kenzo

    This paper describes a vision-based tracking system using an autonomous Quadrotor Unmanned Micro-Aerial Vehicle (MAV). The vision-based control system relies on color target detection and tracking algorithm using integral image, Kalman filters for relative pose estimation, and a nonlinear controller for the MAV stabilization and guidance. The vision algorithm relies on information from a single onboard camera. An arbitrary target can be selected in real-time from the ground control station, thereby outperforming template and learning-based approaches. Experimental results obtained from outdoor flight tests, showed that the vision-control system enabled the MAV to track and hover above the target as long as the battery is available. The target does not need to be pre-learned, or a template for detection. The results from image processing are sent to navigate a non-linear controller designed for the MAV by the researchers in our group.

  10. Inflorescences of alpine cushion plants freeze autonomously and may survive subzero temperatures by supercooling.

    PubMed

    Hacker, Jürgen; Ladinig, Ursula; Wagner, Johanna; Neuner, Gilbert

    2011-01-01

    Freezing patterns in the high alpine cushion plants Saxifraga bryoides, Saxifraga caesia, Saxifraga moschata and Silene acaulis were studied by infrared thermography at three reproductive stages (bud, anthesis, fruit development). The single reproductive shoots of a cushion froze independently in all four species at every reproductive stage. Ice formation caused lethal damage to the respective inflorescence. After ice nucleation, which occurred mainly in the stalk or the base of the reproductive shoot, ice propagated throughout that entire shoot, but not into neighboring shoots. However, anatomical ice barriers within cushions were not detected. The naturally occurring temperature gradient within the cushion appeared to interrupt ice propagation thermally. Consequently, every reproductive shoot needed an autonomous ice nucleation event to initiate freezing. Ice nucleation was not only influenced by minimum temperatures but also by the duration of exposure. At moderate subzero exposure temperatures (-4.3 to -7.7 °C) the number of frozen inflorescences increased exponentially. Due to efficient supercooling, single reproductive shoots remained unfrozen down to -17.4 °C (cooling rate 6 K h?¹). Hence, the observed freezing pattern may be advantageous for frost survival of individual inflorescences and reproductive success of high alpine cushion plants, when during episodic summer frosts damage can be avoided by supercooling. PMID:21151351

  11. Verification and Tuning of an Adaptive Controller for an Unmanned Air Vehicle

    NASA Technical Reports Server (NTRS)

    Crespo, Luis G.; Matsutani, Megumi; Annaswamy, Anuradha M.

    2010-01-01

    This paper focuses on the analysis and tuning of a controller based on the Adaptive Control Technology for Safe Flight (ACTS) architecture. The ACTS architecture consists of a nominal, non-adaptive controller that provides satisfactory performance under nominal flying conditions, and an adaptive controller that provides robustness under off-nominal ones. A framework unifying control verification and gain tuning is used to make the controller s ability to satisfy the closed-loop requirements more robust to uncertainty. In this paper we tune the gains of both controllers using this approach. Some advantages and drawbacks of adaptation are identified by performing a global robustness assessment of both the adaptive controller and its non-adaptive counterpart. The analyses used to determine these characteristics are based on evaluating the degradation in closed-loop performance resulting from uncertainties having increasing levels of severity. The specific adverse conditions considered can be grouped into three categories: aerodynamic uncertainties, structural damage, and actuator failures. These failures include partial and total loss of control effectiveness, locked-in-place control surface deflections, and engine out conditions. The requirements considered are the peak structural loading, the ability of the controller to track pilot commands, the ability of the controller to keep the aircraft s state within the reliable flight envelope, and the handling/riding qualities of the aircraft. The nominal controller resulting from these tuning strategies was successfully validated using the NASA GTM Flight Test Vehicle.

  12. Unmanned air vehicle flow separation control using dielectric barrier discharge plasma at high wind speed

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Huang, Yong; Wang, WanBo; Wang, XunNian; Li, HuaXing

    2014-06-01

    The present paper described an experimental investigation of separation control of an Unmanned Aerial Vehicle (UAV) at high wind speeds. The plasma actuator was based on Dielectric Barrier Discharge (DBD) and operated in a steady manner. The flow over a wing of UAV was performed with smoke flow visualization in the ?0.75 m low speed wind tunnel to reveal the flow structure over the wing so that the locations of plasma actuators could be optimized. A full model of the UAV was experimentally investigated in the ?3.2 m low speed wind tunnel using a six-component internal strain gauge balance. The effects of the key parameters, including the locations of the plasma actuators, the applied voltage amplitude and the operating frequency, were obtained. The whole test model was made of aluminium and acted as a cathode of the actuator. The results showed that the plasma acting on the surface of UAV could obviously suppress the boundary layer separation and reduce the model vibration at the high wind speeds. It was found that the maximum lift coefficient of the UAV was increased by 2.5% and the lift/drag ratio was increased by about 80% at the wind speed of 100 m/s. The control mechanism of the plasma actuator at the test configuration was also analyzed.

  13. Design, fabrication, and characterization of multifunctional wings to harvest solar energy in flapping wing air vehicles

    NASA Astrophysics Data System (ADS)

    Perez-Rosado, Ariel; Gehlhar, Rachel D.; Nolen, Savannah; Gupta, Satyandra K.; Bruck, Hugh A.

    2015-06-01

    Currently, flapping wing unmanned aerial vehicles (a.k.a., ornithopters or robotic birds) sustain very short duration flight due to limited on-board energy storage capacity. Therefore, energy harvesting elements, such as flexible solar cells, need to be used as materials in critical components, such as wing structures, to increase operational performance. In this paper, we describe a layered fabrication method that was developed for realizing multifunctional composite wings for a unique robotic bird we developed, known as Robo Raven, by creating compliant wing structure from flexible solar cells. The deformed wing shape and aerodynamic lift/thrust loads were characterized throughout the flapping cycle to understand wing mechanics. A multifunctional performance analysis was developed to understand how integration of solar cells into the wings influences flight performance under two different operating conditions: (1) directly powering wings to increase operation time, and (2) recharging batteries to eliminate need for external charging sources. The experimental data is then used in the analysis to identify a performance index for assessing benefits of multifunctional compliant wing structures. The resulting platform, Robo Raven III, was the first demonstration of a robotic bird that flew using energy harvested from solar cells. We developed three different versions of the wing design to validate the multifunctional performance analysis. It was also determined that residual thrust correlated to shear deformation of the wing induced by torsional twist, while biaxial strain related to change in aerodynamic shape correlated to lift. It was also found that shear deformation of the solar cells induced changes in power output directly correlating to thrust generation associated with torsional deformation. Thus, it was determined that multifunctional solar cell wings may be capable of three functions: (1) lightweight and flexible structure to generate aerodynamic forces, (2) energy harvesting to extend operational time and autonomy, and (3) sensing of an aerodynamic force associated with wing deformation.

  14. Effects on Air Pollution and Regional Climate of Producing and Using Hydrogen in Fuel Cells in all U.S. OnroadVehicles

    NASA Astrophysics Data System (ADS)

    Jacobson, M. Z.; Colella, W. G.; Golden, D. M.

    2004-12-01

    The purpose of this study was to examine the potential effects on U.S. air pollution and regional climate of switching the current U.S. fleet of onroad motor vehicles to hydrogen fuel-cell vehicles, where hydrogen was produced by (1) steam-reforming of methane, (2) wind energy, or (3) coal gasification. An additional scenario in which the U.S. fleet was switched to gasoline-electric hybrid vehicles was also examined. The model used was GATOR-GCMOM, a global-through-urban-scale nested and parallelized gas, aerosol, transport, radiation, general-circulation, mesoscale, and ocean model. U.S. emission data for the baseline case were obtained from the U.S. National Emission Inventory, which considers 370,000 stack and fugitive sources, 250,000 area sources, and 1700 categories of onroad and nonroad vehicular sources (including motorcycles, passenger vehicles, trucks, recreational vehicles, construction vehicles, farm vehicles, industrial vehicles, etc.). Emission inventories for each of the three hydrogen scenarios were prepared following a process chain analysis that accounted for energy inputs and pollution outputs during all stages of hydrogen and fossil-fuel production, distribution, storage, and end-use. Emitted pollutants accounted for included CO, CO2, H2, H2O, CH4, speciated ROGs, NOx, NH3, SOx, and speciated particulate matter. Results from the first scenario suggest that switching vehicles in the U.S. to hydrogen produced by steam-reforming of methane may reduce emission of NOx, reactive hydrocarbons, CO, CO2, BC, NO3-, and NH4+, but increase CH4, H2, and SO2 (slightly).The switch may also decrease O3 over most of the U.S. but short-term near-surfaces increases may occur over low-vegetated cities (e.g., in Los Angeles and along the Boston-Washington corridor) due to loss of NOx that otherwise titrates O3. The switch is also estimated to decrease PAN, HCHO, and several other pollutants formed in the atmosphere. Isoprene may increase since fewer oxidants (OH, O3) will be available to destroy it. Results for the scenarios involving hydrogen from wind and coal gasification, and from the hybrid scenario will also be discussed, as will regional climate effects (including effects of H2O). Findings to date suggest that, even under a worst-case scenario of 10% hydrogen leakage, the conversion of the current fleet to hydrogen-fuel cell vehicles, where hydrogen is generated by steam-reforming of methane, may result in a measurable improvement in U.S. air quality.

  15. The package cushioning design of the first AST3 and its dynamics analysis

    NASA Astrophysics Data System (ADS)

    Wen, Haikun; Gong, Xuefei; Zhang, Ru

    2012-09-01

    Dome A has been considered as one of the best observation sites on the earth. The First AST3(three Antarctic Survey Telescopes) is on its way to Dome A by the 28th Chinese National Antarctic research expedition. It will be the largest Optic telescope in Dome A after assembling and testing in this austral summer. Firstly, this paper reports the method of collecting the vibration and shock data from ShangHai to Dome A and analyses the data. Secondly, the package cushioning design of the first AST3 is introduced in this paper according to the vibration and shock data. Finally, the paper introduces the result of the dynamics analysis of the design and a test was done to verify the performance of the package cushioning design. The dynamics analysis and the test indicate that the package cushioning design can meet the demand of the Antarctic inland transportation.

  16. Polymer Cushions Functionalized with Lipid Molecules Dong-Chan Lee, Bong-Jun Chang, Luping Yu,*, Shelli L. Frey,

    E-print Network

    Lee, Ka Yee C.

    Polymer Cushions Functionalized with Lipid Molecules Dong-Chan Lee, Bong-Jun Chang, Luping Yu of a biomimicking surface by modification of an end-functionalizable smooth polymer cushion constructed via of a phospholipid bilayer formed by vesicle fusion on the phospholipid-like molecule terminated polymer film

  17. Energy absorption capability of foam-based composite materials and their applications as seat cushions in aircraft crashworthiness

    Microsoft Academic Search

    Hamid Kh. Beheshti

    2004-01-01

    This study is focusing on the application of foam materials in aviation. These materials are being used for acoustic purposes, as padding in the finished interior panels of the aircraft, and as seat cushions. Foams are mostly used in seating applications. Since seat cushion is directly interacting with the body of occupant, it has to be ergonomically comfortable beside of

  18. Extractable trace metals content of dust from vehicle air filters as determined by sequential extraction and flame atomic absorption spectrometry.

    PubMed

    Saracoglu, Sibel; Soylak, Mustafa; Elçi, Latif

    2009-01-01

    A modified four-step sequential extraction procedure developed within the Standards, Measurement, and Testing Program (formally the Community Bureau of Reference) of the European Commission was applied to determine the distribution of Cd, Cu, Fe, and Mn in air filter dust samples collected from vehicles. The four fractions were acid-soluble, reducible, oxidizable, and residual. These fractions have the advantage of providing better insight into the mechanism of association of metals in the dust. The determination of trace metals in dust samples was performed by flame atomic absorption spectrometry. The results obtained after applying the sequential extraction scheme indicated that Cu was the most abundant metal in the organic and residual fractions of the dust matrix. Fe was found mainly in the residual fraction, and the major amounts of Mn and Cd were present in the acid-soluble and bound-to-carbonate fraction. The mean values of Cd, Cu, Fe, and Mn were found to be 15.58, 33.54, 1625, and 180 microg/g, respectively. The results obtained are in agreement with data reported in the literature. PMID:19714990

  19. KCP Activities Supporting the W76LEP Stress Cushions and LK3626 RTV Replacement Material Development

    SciTech Connect

    J. W. Schneider

    2009-10-01

    The S-5370 RTV blown foam previously produced by Dow Corning is no longer commercially available. The S-5370 material has been used on all of Los Alamos National Laboratory (LANL) programs to manufacture Stress Cushions up through the W88. The Kansas City Plant (KCP) did not have a sufficient supply of S-5370 material to cover the schedule requirements for the Program. This report provides information on the numerous activities conducted at KCP involving the development of the Program Stress Cushion and replacement RTV material.

  20. A Control of the Variation of Cushion Pressure of the SES in Heave Motion

    NASA Astrophysics Data System (ADS)

    Kanazawa, Koji; Senba, Hiromitsu; Matsuo, Kensuke; Matsuo, Hideo

    A method is proposed to control the variation of cushion pressure of oscillationg SES (Surface Effect Ship). The peripheral nozzle is attached along the periphery that moves vertically changing the height above the wave surface. The nozzle height is continuously changed in accordance with the motion of the craft. The change of pressure due to the undulation of the traveling surface is compensated by the change of the nozzle height. It has been shown experimentally that the variation of the cushion pressure is effectively controlled adjusting the amplitude and the phase of the vertical motion of the nozzle.

  1. Modeling the vehicle cycle impacts of hybrid electric vehicles

    Microsoft Academic Search

    M. Q. Wang; L. Gaines; R. Cuenca

    1997-01-01

    Pure and hybrid electric vehicles, considered environmentally benign, are being developed to reduce urban air pollutant emissions. The obvious emissions benefit of pure electric vehicles is that they produce no tailpipe emissions. Hybrid electric vehicles have the potential of improving fuel economy and reducing emissions. However, both electric vehicles and hybrid electric vehicles (HEVs) do have their own environmental impacts.

  2. Life-cycle assessment of greenhouse gas and air emissions of electric vehicles: A comparison between China and the U.S.

    NASA Astrophysics Data System (ADS)

    Huo, Hong; Cai, Hao; Zhang, Qiang; Liu, Fei; He, Kebin

    2015-05-01

    We evaluated the fuel-cycle emissions of greenhouse gases (GHGs) and air pollutants (NOx, SO2, PM10, and PM2.5) of electric vehicles (EVs) in China and the United States (U.S.), two of the largest potential markets for EVs in the world. Six of the most economically developed and populated regions in China and the U.S. were selected. The results showed that EV fuel-cycle emissions depend substantially on the carbon intensity and cleanness of the electricity mix, and vary significantly across the regions studied. In those regions with a low share of coal-based electricity (e.g., California), EVs can reduce GHG and air pollutant emissions (except for PM) significantly compared with conventional vehicles. However, in the Chinese regions and selected U.S. Midwestern states where coal dominates in the generation mix, EVs can reduce GHG emissions but increase the total and urban emissions of air pollutants. In 2025, EVs will offer greater reductions in GHG and air pollutant emissions because emissions from power plants will be better controlled; EVs in the Chinese regions examined, however, may still increase SO2 and PM emissions. Reductions of 60-85% in GHGs and air pollutants could be achieved were EVs charged with 80% renewable electricity or the electricity generated from the best available technologies of coal-fired power plants, which are futuristic power generation scenarios.

  3. Evaluation of on-road vehicle CO and NOx National Emission Inventories using an urban-scale source-oriented air quality model

    NASA Astrophysics Data System (ADS)

    Kota, Sri Harsha; Zhang, Hongliang; Chen, Gang; Schade, Gunnar W.; Ying, Qi

    2014-03-01

    The MOBILE6.2 model was replaced by the Motor Vehicle Emission Simulator (MOVES) in 2012 as an official tool recommended by the United States Environmental Protection Agency (US EPA) to predict vehicular pollutant emission factors. In this study, on-road vehicle emission inventories of CO and NOx for Southeast Texas generated by MOVES and MOBILE6.2 in two versions of the 2005 National Emission Inventory (NEI) were studied by comparing predicted CO and NOx using the EPA's Community Multiscale Air Quality (CMAQ) Model incorporated with a source-oriented gas phase chemical mechanism with measurements made at six urban and industrial sites in Southeast Texas. The source tracing technique allows direct determination of contributions of on-road vehicles to overall CO and NOx concentrations and identification of ambient concentration measurements which are mostly impacted by vehicle emissions. By grouping the fractional bias (FB) values of the hourly predictions based on vehicle contributions to total CO or NOx concentrations, clear trends in the FB were observed, indicating systematic biases in the emission inventory for these species. Data points dominated by vehicle emissions suggest that surface CO concentrations due to vehicle exhaust are significantly over-estimated by a factor of 2 using either MOVES or MOBILE6.2. NOx concentrations are overestimated by approximately 20-35% and 70% by using the MOBILE6.2 and MOVES emissions, respectively. Emission scaling runs show that a domain-wide reduction of MOBILE6.2 CO emissions by 60% and NOx emissions by 15-25% leads to better model performance of exhaust CO and NOx concentrations in the current study.

  4. A global meta-analytic contrast of cushion-plant effects on plants and on arthropods

    PubMed Central

    Liczner, Amanda R.

    2014-01-01

    Nurse plant facilitation is a commonly reported plant–plant interaction and is an important factor influencing community structure in stressful environments. Cushion plants are an example of alpine nurse plants that modify microclimatic conditions within their canopies to create favourable environments for other plants. In this meta-analysis, the facilitative effects of cushion plants was expanded from previous syntheses of the topic and the relative strength of facilitation for other plants and for arthropods were compared globally.The abundance, diversity, and species presence/absence effect size estimates were tested as plant responses to nurse plants and a composite measure was tested for arthropods. The strength of facilitation was on average three times greater for arthropods relative to all plant responses to cushions. Plant species presence, i.e., frequency of occurrence, was not enhanced by nurse-plants. Cushion plants nonetheless acted as nurse plants for both plants and arthropods in most alpine contexts globally, and although responses by other plant species currently dominate the facilitation literature, preliminary synthesis of the evidence suggests that the potential impacts of nurses may be even greater for other trophic levels. PMID:24688848

  5. Weakly coupled lipid bilayer membranes on multistimuli-responsive poly(N-isopropylacrylamide) copolymer cushions.

    PubMed

    Kaufmann, Martin; Jia, Yunfei; Werner, Carsten; Pompe, Tilo

    2011-01-18

    Polymer-cushioned lipid bilayers are frequently used to mimic the native environment of cellular membranes in respect to the extracellular matrix and intracellular structures. With the aim to actively tune lipid membrane characteristics, we pursue the approach to use temperature and pH responsive polymer thin films of poly(N-isopropylacrylamide-co-carboxyacrylamide) (PNIPAAm-co-carboxyAAM) as cushions for supported lipid bilayers. A cationic lipid bilayer composed of dioleoylphosphatidylcholine (DOPC) and dioleoyltrimethylammoniumpropane (DOTAP) (9:1) was formed on top of the polymer thin film in a drying/rehydration process. Fluorescence recovery after photobleaching (FRAP) yielded higher lipid diffusion coefficients (6.3-9.6 ?m(2) s(-1)) on polymer cushions in comparison to solid glass supports (3.0-5.9 ?m(2) s(-1)). No correlation of the lipid mobility was found with the swelling state of (PNIPAAm-co-carboxyAAM), which is ascribed to restrained interfacial electrostatic interactions and dispersion forces. The results revealed a minimal coupling of the lipid bilayer with the polymer cushions, and thus, bilayers supported by (PNIPAAm-co-carboxyAAM) provide interesting opportunities for unperturbed lipid diffusion combined with control of transmembrane protein mobility due to the impact of a tunable frictional drag. PMID:21158389

  6. Ethical and economic issues in the use of zero-emission vehicles as a component of an air-pollution mitigation strategy.

    PubMed

    Duvall, Tim; Englander, Fred; Englander, Valerie; Hodson, Thomas J; Marpet, Mark

    2002-10-01

    The air pollution generated by motor vehicles and by static sources is, in certain geographic areas, a very serious problem, a problem that exists because of a failure of the marketplace. To address this marketplace failure, the State of California has mandated that by 2003, 10% of the Light-Duty Vehicle Fleet (LDV) be composed of Zero-Emission Vehicles (ZEVs). However, the policy-making process that was utilized to generate the ZEV mandate was problematic and the resulting ZEV mandate is economically unsound. Moreover, an ethical analysis, based primarily upon the work of John Rawls, suggests that implementation of the California ZEV mandate is--in spite of the wide latitude that ought to be given to policy decision makers--unethical. A more ethical and economically efficient approach to the pollution caused by marketplace failure is one that relies on market incentives and thereby achieves the desired improvement in air quality by appealing both to the self-interest of motorists and to those businesses that are directly or indirectly involved with the automobile industry. Such an approach would take better advantage of the creative forces of the market and improvements in technology over time and avoid the infringements on individual liberty and fairness embodied in the ZEV mandate. PMID:12501725

  7. Sucrose Cushion Tucson Marine Phage Lab Page 1 of 4

    E-print Network

    Sullivan, Matthew B.

    tubes with SM buffer or sterile water. The SW 40 tubes hold 12 ml total or serological pipet, pull off the 9.5 ml sample layer. Then pull off are completed. Air dry the pellets in a fume hood for 15-20 min. Add

  8. UPDATED PHOTOCHEMICAL MODELING FOR CALIFORNIA'S SOUTH COAST AIR BASIN: COMPARISON OF CHEMICAL MECHANISMS AND MOTOR VEHICLE EMISSION INVENTORIES. (R824792)

    EPA Science Inventory

    Large uncertainties remain in photochemical models used to relate emissions of VOC and NO x to ambient O3 concentrations. Bias in motor vehicle emission estimates for VOC has been a long-standing concern. An improved Eul...

  9. The Alpine Cushion Plant Silene acaulis as Foundation Species: A Bug’s-Eye View to Facilitation and Microclimate

    PubMed Central

    Molenda, Olivia; Reid, Anya; Lortie, Christopher J.

    2012-01-01

    Alpine ecosystems are important globally with high levels of endemic and rare species. Given that they will be highly impacted by climate change, understanding biotic factors that maintain diversity is critical. Silene acaulis is a common alpine nurse plant shown to positively influence the diversity and abundance of organisms–predominantly other plant species. The hypothesis that cushion or nurse plants in general are important to multiple trophic levels has been proposed but rarely tested. Alpine arthropod diversity is also largely understudied worldwide, and the plant-arthropod interactions reported are mostly negative, that is,. herbivory. Plant and arthropod diversity and abundance were sampled on S. acaulis and at paired adjacent microsites with other non-cushion forming vegetation present on Whistler Mountain, B.C., Canada to examine the relative trophic effects of cushion plants. Plant species richness and abundance but not Simpson’s diversity index was higher on cushion microsites relative to other vegetation. Arthropod richness, abundance, and diversity were all higher on cushion microsites relative to other vegetated sites. On a microclimatic scale, S. acaulis ameliorated stressful conditions for plants and invertebrates living inside it, but the highest levels of arthropod diversity were observed on cushions with tall plant growth. Hence, alpine cushion plants can be foundation species not only for other plant species but other trophic levels, and these impacts are expressed through both direct and indirect effects associated with altered environmental conditions and localized productivity. Whilst this case study tests a limited subset of the membership of alpine animal communities, it clearly demonstrates that cushion-forming plant species are an important consideration in understanding resilience to global changes for many organisms in addition to other plants. PMID:22655035

  10. The alpine cushion plant Silene acaulis as foundation species: a bug's-eye view to facilitation and microclimate.

    PubMed

    Molenda, Olivia; Reid, Anya; Lortie, Christopher J

    2012-01-01

    Alpine ecosystems are important globally with high levels of endemic and rare species. Given that they will be highly impacted by climate change, understanding biotic factors that maintain diversity is critical. Silene acaulis is a common alpine nurse plant shown to positively influence the diversity and abundance of organisms--predominantly other plant species. The hypothesis that cushion or nurse plants in general are important to multiple trophic levels has been proposed but rarely tested. Alpine arthropod diversity is also largely understudied worldwide, and the plant-arthropod interactions reported are mostly negative, that is,. herbivory. Plant and arthropod diversity and abundance were sampled on S. acaulis and at paired adjacent microsites with other non-cushion forming vegetation present on Whistler Mountain, B.C., Canada to examine the relative trophic effects of cushion plants. Plant species richness and abundance but not Simpson's diversity index was higher on cushion microsites relative to other vegetation. Arthropod richness, abundance, and diversity were all higher on cushion microsites relative to other vegetated sites. On a microclimatic scale, S. acaulis ameliorated stressful conditions for plants and invertebrates living inside it, but the highest levels of arthropod diversity were observed on cushions with tall plant growth. Hence, alpine cushion plants can be foundation species not only for other plant species but other trophic levels, and these impacts are expressed through both direct and indirect effects associated with altered environmental conditions and localized productivity. Whilst this case study tests a limited subset of the membership of alpine animal communities, it clearly demonstrates that cushion-forming plant species are an important consideration in understanding resilience to global changes for many organisms in addition to other plants. PMID:22655035

  11. Effect of Mitovirus infection on formation of infection cushions and virulence of Botrytis cinerea

    Microsoft Academic Search

    Lei Zhang; Ming De Wu; Guo Qing Li; Dao Hong Jiang; Hung Chang Huang

    2010-01-01

    This study was conducted to investigate mechanisms involved in hypovirulence of strain CanBc-1 of Botrytis cinerea. The hypovirulent strain CanBc-1 was compared with the virulent strains CanBc-1c-66 and CanBc-2 of B. cinerea for formation of infection cushions on onion bulbs and on leaves of oilseed rape and tomato, as well as for production of pectinase, toxic metabolites, oxalic acid and

  12. Variations in Rear Seat Cushion Properties and the Effects on Submarining

    Microsoft Academic Search

    Ben Beck; Julie Brown; Lynne E. Bilston

    2011-01-01

    Objective: This study aims to investigate the effects of seating posture and seat cushion properties on submarining risk for rear seated children.Methods: An instrumented 6-year-old Hybrid III dummy restrained by an inertial-reel 3-point seat belt was subjected to simulated frontal impacts (?v = 28.8 km\\/h, peak acceleration = 16 g). Dummy motion was captured using high-speed digital video. Head acceleration,

  13. Liner-on-plasma system near stagnation: Stabilizing effect of a magnetic cushion

    SciTech Connect

    Ryutov, D. D. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)

    2011-06-15

    This brief communication is concerned with the adiabatic compression of a high-beta plasma by a heavy liner. Elongated cylindrical and quasi-cylindrical geometries are considered. The magnetic field in a plasma is parallel to the axis, whereas the drive field has azimuthal direction. During the liner acceleration, the most dangerous modes are axisymmetric (m = 0) modes. Near stagnation, these modes are further amplified at the inner surface, as the liner is decelerated by the isotropic pressure of a high-beta plasma. This picture, however, is not complete: due to a heat loss from the plasma core to the relatively cold liner, a zone of a strong axial magnetic field may appear between a hot, high-beta plasma and a cold liner. This magnetic cushion is backed from inside by a very high-beta plasma. The stability of such a system with respect to m = 0 modes is studied and the conclusion is drawn that the stabilizing effect of the magnetic cushion remains strong even for relatively thin cushions and moderate magnetic fields in them.

  14. Liner-on-plasma system near stagnation: Stabilizing effect of a magnetic cushion

    NASA Astrophysics Data System (ADS)

    Ryutov, D. D.

    2011-06-01

    This brief communication is concerned with the adiabatic compression of a high-beta plasma by a heavy liner. Elongated cylindrical and quasi-cylindrical geometries are considered. The magnetic field in a plasma is parallel to the axis, whereas the drive field has azimuthal direction. During the liner acceleration, the most dangerous modes are axisymmetric (m = 0) modes. Near stagnation, these modes are further amplified at the inner surface, as the liner is decelerated by the isotropic pressure of a high-beta plasma. This picture, however, is not complete: due to a heat loss from the plasma core to the relatively cold liner, a zone of a strong axial magnetic field may appear between a hot, high-beta plasma and a cold liner. This magnetic cushion is backed from inside by a very high-beta plasma. The stability of such a system with respect to m = 0 modes is studied and the conclusion is drawn that the stabilizing effect of the magnetic cushion remains strong even for relatively thin cushions and moderate magnetic fields in them.

  15. Volatile organic chemical emissions from carpet cushions: Screening measurements. Final report

    SciTech Connect

    Hodgson, A.T.; Phan, T.A.

    1994-05-01

    The US Consumer Product Safety Commission (CPSC) has received complaints from consumers regarding the occurrence of adverse health effects following the installation of new carpeting (Schachter, 1990). Carpet systems are suspected of emitting chemicals which may be the cause of these complaints, as well as objectionable odors. Carpets themselves have been shown to emit a variety of volatile organic compounds (VOCs). The objective of this study was to screen the representative samples of carpet cushions for emissions of individual VOCS, total VOCs (TVOC), formaldehyde, and, for the two types of polyurethane cushions, isomers of toluene diisocyanate (TDI). The measurements of VOCS, TVOC and formaldehyde were made over six-hour periods using small-volume (4-L) dynamic chambers. Sensitive gas chromatography-mass spectrometry (GC-MS) techniques were used to identify many of the VOCs emitted by the cushion samples and to obtain quantitative estimates of the emission rates of selected compounds. Separate screening measurements were conducted for TDI. The data from the screening measurements were used by the CPSC`s Health Sciences Laboratory to help design and conduct week-long measurements of emission rates of selected compounds.

  16. Low-cost multi-vehicle air temperature measurements for heat load assessment in local-scale climate applications

    NASA Astrophysics Data System (ADS)

    Zuvela-Aloise, Maja; Weyss, Gernot; Aloise, Giulliano; Mifka, Boris; Löffelmann, Philemon; Hollosi, Brigitta; Nemec, Johana; Vucetic, Visnja

    2014-05-01

    In the recent years there has been a strong interest in exploring the potential of low-cost measurement devices as alternative source of meteorological monitoring data, especially in the urban areas where high-density observations become crucial for appropriate heat load assessment. One of the simple, but efficient approaches for gathering large amount of spatial data is through mobile measurement campaigns in which the sensors are attached to driving vehicles. However, non-standardized data collecting procedure, instrument quality, their response-time and design, variable device ventilation and radiation protection influence the reliability of the gathered data. We investigate what accuracy can be expected from the data collected through low-cost mobile measurements and whether the achieved quality of the data is sufficient for validation of the state-of-the-art local-scale climate models. We tested 5 types of temperature sensors and data loggers: Maxim iButton, Lascar EL-USB-2-LCD+ and Onset HOBO UX100-003 as market available devices and self-designed solar powered Arduino-based data loggers combined with the AOSONG AM2315 and Sensirion SHT21 temperature and humidity sensors. The devices were calibrated and tested in stationary mode at the Austrian Weather Service showing accuracy between 0.1°C and 0.8°C, which was mostly within the device specification range. In mobile mode, the best response-time was found for self-designed device with Arduino-based data logger and Sensirion SHT21 sensor. However, the device lacks the mechanical robustness and should be further improved for broad-range applications. We organized 4 measurement tours: two taking place in urban environment (Vienna, Austria in July 2011 and July 2013) and two in countryside with complex terrain of Mid-Adriatic islands (Hvar and Korcula, Croatia in August 2013). Measurements were taken on clear-sky, dry and hot days. We combined multiple devices attached to bicycle and cars with different radiation protection. Duration of each measurement tour lasted approximately 2 hours covering the distances in radius of about 10-30 km, logging the air temperature and geographical positioning in intervals of 1-5 seconds. The collected data were aggregated on a 100 m horizontal resolution grid and compared with the local-scale climate modelling simulations with the urban climate model MUKLIMO3 initialized with the atmospheric conditions for a given day. Both measurement and modelling results show similar features for distinct local climate zones (built-up area, near water environment, forest, parks, agricultural area, etc). The spatial gradients in temperature can be assigned to different orographical and land use characteristics. Even if many ambiguities remain in both modelling and the measurement approach, the collected data provide useful information for local-scale heat assessment and can serve as a base to increase the model reliability, especially in areas with low data coverage.

  17. Metal-Air Electric Vehicle Battery: Sustainable, High-Energy Density, Low-Cost Electrochemical Energy Storage – Metal-Air Ionic Liquid (MAIL) Batteries

    SciTech Connect

    None

    2009-12-21

    Broad Funding Opportunity Announcement Project: ASU is developing a new class of metal-air batteries. Metal-air batteries are promising for future generations of EVs because they use oxygen from the air as one of the battery’s main reactants, reducing the weight of the battery and freeing up more space to devote to energy storage than Li-Ion batteries. ASU technology uses Zinc as the active metal in the battery because it is more abundant and affordable than imported lithium. Metal-air batteries have long been considered impractical for EV applications because the water-based electrolytes inside would decompose the battery interior after just a few uses. Overcoming this traditional limitation, ASU’s new battery system could be both cheaper and safer than today’s Li-Ion batteries, store from 4-5 times more energy, and be recharged over 2,500 times.

  18. Mobile air quality studies (MAQS) in inner cities: particulate matter PM10 levels related to different vehicle driving modes and integration of data into a geographical information program

    PubMed Central

    2012-01-01

    Background Particulate matter (PM) is assumed to exert a major burden on public health. Most studies that address levels of PM use stationary measure systems. By contrast, only few studies measure PM concentrations under mobile conditions to analyze individual exposure situations. Methods By combining spatial-temporal analysis with a novel vehicle-mounted sensor system, the present Mobile Air Quality Study (MAQS) aimed to analyse effects of different driving conditions in a convertible vehicle. PM10 was continuously monitored in a convertible car, driven with roof open, roof closed, but windows open, or windows closed. Results PM10 values inside the car were nearly always higher with open roof than with roof and windows closed, whereas no difference was seen with open or closed windows. During the day PM10 values varied with high values before noon, and occasional high median values or standard deviation values due to individual factors. Vehicle speed in itself did not influence the mean value of PM10; however, at traffic speed (10 – 50 km/h) the standard deviation was large. No systematic difference was seen between PM10 values in stationary and mobile cars, nor was any PM10 difference observed between driving within or outside an environmental (low emission) zone. Conclusions The present study has shown the feasibility of mobile PM analysis in vehicles. Individual exposure of the occupants varies depending on factors like time of day as well as ventilation of the car; other specific factors are clearly identifiably and may relate to specific PM10 sources. This system may be used to monitor individual exposure ranges and provide recommendations for preventive measurements. Although differences in PM10 levels were found under certain ventilation conditions, these differences are likely not of concern for the safety and health of passengers. PMID:23031208

  19. International Micro Air Vehicle Conference and Flight Competition (IMAV2013) 17-20 September 2013, Toulouse, France

    E-print Network

    Boyer, Edmond

    fast and physically accurate modelling of the aerodynamic characteristics of each candidate by using.g. aerodynamics,structure, propulsion,control,...) modelled seperately in order to see their final effect on the performance of the vehicle. Assistant Professor in Applied Aerodynamics Assistant Professor in Flight Dynamics

  20. Autonomous vehicles

    SciTech Connect

    Meyrowitz, A.L. [Navy Center for Applied Research in Artificial Intelligence, Washington, DC (United States)] [Navy Center for Applied Research in Artificial Intelligence, Washington, DC (United States); Blidberg, D.R. [Autonomous Undersea Systems Inst., Lee, NH (United States)] [Autonomous Undersea Systems Inst., Lee, NH (United States); Michelson, R.C. [Georgia Tech Research Inst., Smyrna, GA (United States)] [Georgia Tech Research Inst., Smyrna, GA (United States); [International Association for Unmanned Vehicle Systems, Smyrna, GA (United States)

    1996-08-01

    There are various kinds of autonomous vehicles (AV`s) which can operate with varying levels of autonomy. This paper is concerned with underwater, ground, and aerial vehicles operating in a fully autonomous (nonteleoperated) mode. Further, this paper deals with AV`s as a special kind of device, rather than full-scale manned vehicles operating unmanned. The distinction is one in which the AV is likely to be designed for autonomous operation rather than being adapted for it as would be the case for manned vehicles. The authors provide a survey of the technological progress that has been made in AV`s, the current research issues and approaches that are continuing that progress, and the applications which motivate this work. It should be noted that issues of control are pervasive regardless of the kind of AV being considered, but that there are special considerations in the design and operation of AV`s depending on whether the focus is on vehicles underwater, on the ground, or in the air. The authors have separated the discussion into sections treating each of these categories.

  1. Crystallization Behavior of M97 Series Silicone Cushions

    SciTech Connect

    Chien, A.; DeTeresa, S.; Cohenour, R.; Schnieder, J.; LeMay, J.; Balazs, B.

    2000-09-07

    M97 series siloxanes are poly(dimethyl-diphenyl) siloxanes that are reinforced through a mixture of precipitated and fumed silica fillers which are blended in through the addition of a short chain polydimethylsiloxane processing aid. M97 silicones exhibit crystallization at -80.25 C by thermal (modulated differential scanning calorimetry) and mechanical (dynamic mechanical analysis) techniques. Isothermal dynamic mechanical analysis experiments illustrated that crystallization occurred over a 1.8 hour period in silica-filled systems and 2.8 hours in unfilled systems. The onset of crystallization typically occurred after a 30 minute incubation/nucleation period. {gamma}-radiation caused the crystallization rate to decrease proportionally with dosage, but did not decrease the amount of crystallization that ultimately occurred. Irradiation in vacuum resulted in slower overall crystallization rates compared to air irradiation due to increased crosslinking of the polymer matrix under vacuum. Modulated differential scanning calorimetry contrasted the crystallization and melting behavior of pure PDMS versus the M97 base polymer and helped determine which component of the composite was the origin of the crystallization phenomena.

  2. Flapping Wing Micro Air Vehicles: An Analysis of the Importance of the Mass of the Wings to Flight Dynamics, Stability, and Control

    NASA Astrophysics Data System (ADS)

    Orlowski, Christopher T.

    The flight dynamics, stability, and control of a model flapping wing micro air vehicle are analyzed with a focus on the inertial and mass effects of the wings on the position and Orientation of the body. A multi-body, flight dynamics model is derived from first principles. The multi-body model predicts significant differences in the position and orientation of the flapping wing micro air vehicle, when compared to a flight dynamics model based on the standard aircraft, or six degree of freedom, equations of motion. The strongly coupled, multi-body equations of motion are transformed into first order form using an approximate inverse and appropriate assumptions. Local (naive) averaging of the first order system does not produce an accurate result and a new approximation technique named 'quarter-cycle' averaging is proposed. The technique is effective in reducing the error by at least an order of magnitude for three reference flight conditions. A stability analysis of the local averaged equations of motions, in the vicinity of a hover condition, produces a modal structure consist with the most common vertical takeoff or landing structure and independent stability analyses of the linearized flight dynamics of insect models. The inclusion of the wing effects produces a non-negligible change in the linear stability of a hawkmoth-sized model. The hovering solution is shown, under proper control, to produce a limit cycle. The control input to achieve a limit cycle is different if the flight dynamics model includes the wing effects or does not include the wing effects. Improper control input application will not produce the desired limit cycle effects. A scaling analysis is used to analyze the relative importance of the mass of the wings, based on the quarter-cycle approximation. The conclusion of the scaling analysis is that the linear momentum effects of the wings are always important in terms of the inertial position of the flapping wing micro air vehicle. Above a flapping frequency of approximately 30-40 Hz, the mass and inertial effects of the wings on the orientation of the body can be neglected.

  3. N-acetyl-S-(n-propyl)-l-cysteine in urine from workers exposed to 1-bromopropane in foam cushion spray adhesives.

    PubMed

    Hanley, Kevin W; Petersen, Martin R; Cheever, Kenneth L; Luo, Lian

    2009-10-01

    1-Bromopropane (1-BP) has been marketed as an alternative for ozone depleting and other solvents; it is used in aerosol products, adhesives, metal, precision, and electronics cleaning solvents. Mechanisms of toxicity of 1-BP are not fully understood, but it may be a neurological and reproductive toxicant. Sparse exposure information prompted this study using 1-BP air sampling and urinary metabolites. Mercapturic acid conjugates are excreted in urine from 1-BP metabolism involving debromination. Research objectives were to evaluate the utility of urinary N-acetyl-S-(n-propyl)-L-cysteine (AcPrCys) for assessing exposure to 1-BP and compare it to urinary bromide [Br((-))] previously reported for these workers. Forty-eight-hour urine specimens were obtained from 30 workers at two factories where 1-BP spray adhesives were used to construct polyurethane foam seat cushions. Urine specimens were also obtained from 21 unexposed control subjects. All the workers' urine was collected into composite samples representing three time intervals: at work, after work but before bedtime, and upon awakening. Time-weighted average (TWA) geometric mean breathing zone concentrations were 92.4 and 10.5 p.p.m. for spraying and non-spraying jobs, respectively. Urinary AcPrCys showed the same trend as TWA exposures to 1-BP: higher levels were observed for sprayers. Associations of AcPrCys concentrations, adjusted for creatinine, with 1-BP TWA exposure were statistically significant for both sprayers (P < 0.05) and non-sprayers (P < 0.01). Spearman correlation coefficients for AcPrCys and Br((-)) analyses determined from the same urine specimens were highly correlated (P < 0.0001). This study confirms that urinary AcPrCys is an important 1-BP metabolite and an effective biomarker for highly exposed foam cushion workers. PMID:19706636

  4. Bacterial community of cushion plant Thylacospermum ceaspitosum on elevational gradient in the Himalayan cold desert

    PubMed Central

    ?eháková, Klára; Chro?áková, Alica; Krišt?fek, Václav; Kuchtová, Barbora; ?apková, Kate?ina; Scharfen, Josef; ?apek, Petr; Doležal, Ji?í

    2015-01-01

    Although bacterial assemblages are important components of soils in arid ecosystems, the knowledge about composition, life-strategies, and environmental drivers is still fragmentary, especially in remote high-elevation mountains. We compared the quality and quantity of heterotrophic bacterial assemblages between the rhizosphere of the dominant cushion-forming plant Thylacospermum ceaspitosum and its surrounding bulk soil in two mountain ranges (East Karakoram: 4850–5250 m and Little Tibet: 5350–5850 m), in communities from cold steppes to the subnival zone in Ladakh, arid Trans-Himalaya, northwest India. Bacterial communities were characterized by molecular fingerprinting in combination with culture-dependent methods. The effects of environmental factors (elevation, mountain range, and soil physico-chemical parameters) on the bacterial community composition and structure were tested by multivariate redundancy analysis and conditional inference trees. Actinobacteria dominate the cultivable part of community and represent a major bacterial lineage of cold desert soils. The most abundant genera were Streptomyces, Arthrobacter, and Paenibacillus, representing both r- and K-strategists. The soil texture is the most important factor for the community structure and the total bacteria counts. Less abundant and diverse assemblages are found in East Karakoram with coarser soils derived from leucogranite bedrock, while more diverse assemblages in Little Tibet are associated with finer soils derived from easily weathering gneisses. Cushion rhizosphere is in general less diverse than bulk soil, and contains more r-strategists. K-strategists are more associated with the extremes of the gradient, with drought at lowest elevations (4850–5000 m) and frost at the highest elevations (5750–5850 m). The present study illuminates the composition of soil bacterial assemblages in relation to the cushion plant T. ceaspitosum in a xeric environment and brings important information about heterotrophic bacteria in Himalayan soil. PMID:25932023

  5. Advanced computer technology - An aspect of the Terminal Configured Vehicle program. [air transportation capacity, productivity, all-weather reliability and noise reduction improvements

    NASA Technical Reports Server (NTRS)

    Berkstresser, B. K.

    1975-01-01

    NASA is conducting a Terminal Configured Vehicle program to provide improvements in the air transportation system such as increased system capacity and productivity, increased all-weather reliability, and reduced noise. A typical jet transport has been equipped with highly flexible digital display and automatic control equipment to study operational techniques for conventional takeoff and landing aircraft. The present airborne computer capability of this aircraft employs a multiple computer simple redundancy concept. The next step is to proceed from this concept to a reconfigurable computer system which can degrade gracefully in the event of a failure, adjust critical computations to remaining capacity, and reorder itself, in the case of transients, to the highest order of redundancy and reliability.

  6. Aerothermodynamic Testing of Protuberances and Penetrations on the NASA Crew Exploration Vehicle Heat Shield in the NASA Langley 20-Inch Mach 6 Air Tunnel

    NASA Technical Reports Server (NTRS)

    Liechty, Derek S.

    2008-01-01

    An experimental wind tunnel program is being conducted in support of an Agency wide effort to develop a replacement for the Space Shuttle and to support the NASA s long-term objective of returning to the moon and then on to Mars. This paper documents experimental measurements made on several scaled ceramic heat transfer models of the proposed Crew Exploration Vehicle. Global heat transfer images and heat transfer distributions obtained using phosphor thermography were used to infer interference heating on the Crew Exploration Vehicle Cycle 1 heat shield from local protuberances and penetrations for both laminar and turbulent heating conditions. Test parametrics included free stream Reynolds numbers of 1.0x10(exp 6)/ft to 7.25x10(exp 6)/ft in Mach 6 air at a fixed angle-of-attack. Single arrays of discrete boundary layer trips were used to trip the boundary layer approaching the protuberances/penetrations to a turbulent state. Also, the effects of three compression pad diameters, two radial locations of compression pad/tension tie location, compression pad geometry, and rotational position of compression pad/tension tie were examined. The experimental data highlighted in this paper are to be used to validate CFD tools that will be used to generate the flight aerothermodynamic database. Heat transfer measurements will also assist in the determination of the most appropriate engineering methods that will be used to assess local flight environments associated with protuberances/penetrations of the CEV thermal protection system.

  7. An Innovative Approach for Data Collection and Handling to Enable Advancements in Micro Air Vehicle Persistent Surveillance 

    E-print Network

    Goodnight, Ryan David

    2010-10-12

    be carrying a specific subset of hardware along with it during its mission. 2.1.1 Necessary Hardware and Examples The selection of a propulsion system is one of the primary drivers in how an MAV flight unit will eventually take form. Because... the propulsion of the MAV is 17 directly related to its fuel source, several factors must be considered prior to making the final decision. For instance, a gas powered motor would not be a desirable selection for a vehicle that will be intended for multiple...

  8. Cushions of Thylacospermum caespitosum (Caryophyllaceae) do not facilitate other plants under extreme altitude and dry conditions in the north-west Himalayas

    PubMed Central

    de Bello, Francesco; Doležal, Ji?í; Dvorský, Miroslav; Chlumská, Zuzana; ?eháková, Klára; Klimešová, Jitka; Klimeš, Leoš

    2011-01-01

    Background Cushion plants are commonly considered as keystone nurse species that ameliorate the harsh conditions they inhabit in alpine ecosystems, thus facilitating other species and increasing alpine plant biodiversity. A literature search resulted in 25 key studies showing overwhelming facilitative effects of different cushion plants and hypothesizing greater facilitation with increased environmental severity (i.e. higher altitude and/or lower rainfall). At the same time, emerging ecological theory alongside the cushion-specific literature suggests that facilitation might not always occur under extreme environmental conditions, and especially under high altitude and dryness. Methods To assess these hypotheses, possible nursing effects of Thylacospermum caespitosum (Caryophyllaceae) were examined at extremely high altitude (5900 m a.s.l.) and in dry conditions (precipitation <100 mm year?1) in Eastern Ladakh, Trans-Himalaya. This is, by far, the highest site, and the second driest, at which the effects of cushions have been studied so far. Key Results In accordance with the theoretical predictions, no nursing effects of T. caespitosum on other alpine plants were detected. The number and abundance of species were greater outside cushions than within and on the edge of cushions. None of the 13 species detected was positively associated with cushions, while nine of them were negatively associated. Plant diversity increased with the size of the area sampled outside cushions, but no species–area relationship was found within cushions. Conclusions The results support the emerging theoretical prediction of restricted facilitative effects under extreme combinations of cold and dryness, integrating these ideas in the context of the ecology of cushion plants. This evidence suggests that cases of missing strong facilitation are likely to be found in other extreme alpine conditions. PMID:21813564

  9. Performance study on three-stage power system of compressed air vehicle based on single-screw expander

    Microsoft Academic Search

    Wei He; YuTing Wu; ChongFang Ma; GuoYuan Ma

    2010-01-01

    A new compressed-air engine system based on three-stage single screw expander was proposed to improve the performance of power\\u000a system. Three different structure styles were presented, and the studies on the power performance and the distribution of\\u000a expansion ratios between stages were carried out by programming and mathematical modeling of each style. Research results\\u000a indicated that the best matches of

  10. Computer graphic of Lockheed Martin X-33 Reusable Launch Vehicle (RLV) mounted on NASA 747 ferry air

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This is an artist's conception of the NASA/Lockheed Martin X-33 Advanced Technology Demonstrator being carried on the back of the 747 Shuttle Carrier Aircraft. This was a concept for moving the X-33 from its landing site back to NASA's Dryden Flight Research Center, Edwards, California. The X-33 was a technology demonstrator vehicle for the Reusable Launch Vehicle (RLV). The RLV technology program was a cooperative agreement between NASA and industry. The goal of the RLV technology program was to enable significant reductions in the cost of access to space, and to promote the creation and delivery of new space services and other activities that will improve U.S. economic competitiveness. NASA Headquarter's Office of Space Access and Technology oversaw the RLV program, which was being managed by the RLV Office at NASA's Marshall Space Flight Center, located in Huntsville, Alabama. Responsibilities of other NASA Centers included: Johnson Space Center, Houston, Texas, guidance navigation and control technology, manned space systems, and health technology; Ames Research Center, Mountain View, CA., thermal protection system testing; Langley Research Center, Langley, Virginia, wind tunnel testing and aerodynamic analysis; and Kennedy Space Center, Florida, RLV operations and health management. Lockheed Martin's industry partners in the X-33 program are: Astronautics, Inc., Denver, Colorado, and Huntsville, Alabama; Engineering & Science Services, Houston, Texas; Manned Space Systems, New Orleans, LA; Sanders, Nashua, NH; and Space Operations, Titusville, Florida. Other industry partners are: Rocketdyne, Canoga Park, California; Allied Signal Aerospace, Teterboro, NJ; Rohr, Inc., Chula Vista, California; and Sverdrup Inc., St. Louis, Missouri.

  11. The Alpine Cushion Plant Silene acaulis as Foundation Species: A Bug’s-Eye View to Facilitation and Microclimate

    Microsoft Academic Search

    Olivia Molenda; Anya Reid; Christopher J. Lortie

    2012-01-01

    Alpine ecosystems are important globally with high levels of endemic and rare species. Given that they will be highly impacted by climate change, understanding biotic factors that maintain diversity is critical. Silene acaulis is a common alpine nurse plant shown to positively influence the diversity and abundance of organisms–predominantly other plant species. The hypothesis that cushion or nurse plants in

  12. Nurse plant effect of the cushion plant Silene acaulis (L.) Jacq. in an alpine environment in the subarctic Scandes, Sweden

    Microsoft Academic Search

    Henrik Antonsson; Robert G. Björk; Ulf Molau

    2009-01-01

    Background: Facilitation plays important roles in the structuring of plant communities and several studies have found that it tends to increase with environmental severity in alpine plant communities. In addition, cushion plants have been shown to act as nurse plants, moderating extreme environmental conditions, and providing resources for other species, with substantial effects on local plant diversity.Aims: This study addresses

  13. Modal analysis of an artificial wing mimicking an Allomyrina dichotoma beetle's hind wing for flapping-wing micro air vehicles by noncontact measurement techniques

    NASA Astrophysics Data System (ADS)

    Ha, Ngoc San; Jin, Tailie; Goo, Nam Seo

    2013-05-01

    Recently, the development of flapping-wing micro air vehicles (FW-MAV) for operation in extreme environmental conditions has demanded properly designed, biologically inspired wings that can produce enough lift force to keep the vehicles aloft. The structural analysis of an artificial wing is carried out in the design of an FW-MAV. In this study, the dynamic characteristics of an artificial wing mimicking an Allomyrina dichotoma beetle's hind wing were investigated by a non-contact measurement method. The natural frequencies, mode shapes, and damping ratios of the first three basic vibration modes in the operating frequency range were determined using a Bruel & Kjaer (B&K) fast Fourier transform analyzer, along with a laser sensor. The laser sensor was used to obtain the displacement history of the marked points on the wing to calculate the frequency response function. To confirm the results, a three-dimensional digital image correlation (3D-DIC) method, as well as high speed digital cameras, were employed to construct the mode shapes of the wing when it was vibrated at a pre-determined natural frequency. The mode shapes by the DIC method showed good agreement with those by the laser displacement sensor. These results provide a method for the modal analysis of a light weight structure like an insect wing as well as for the construction of the mode shapes using DIC. The high speed 3D-DIC method, used successfully in mode shape measurements, can also be used to study the wing deformation of an insect during flight, which is challenging in an insect study.

  14. Direct compression of cushion-layered ethyl cellulose-coated extended release pellets into rapidly disintegrating tablets without changes in the release profile.

    PubMed

    Hosseini, Armin; Körber, Martin; Bodmeier, Roland

    2013-12-01

    The aim of this study was to develop and optimize a segregation-free ethyl cellulose-coated extended release multiparticulate formulation to be compressed into tablets without affecting the drug release. Standard tableting excipients (e.g., microcrystalline cellulose, lactose or sorbitol) were layered onto ethyl cellulose-coated propranolol hydrochloride pellets to form a cushion layer in order to eliminate segregation problems normally resulting from particle size difference between coated pellets and excipient powders and second to protect the integrity of the brittle ethyl cellulose coating during compression. The disintegration behavior of the tablets depended strongly on the composition of the cushion layer. Rapid tablet disintegration was obtained with microcrystalline cellulose and the disintegrant sodium croscarmellose. However, the drug release from these cushion-layered pellets still increased upon compression. Incorporation of a glidant into the cushion layer or between the cushion layer and the ethyl cellulose coating reduced the compression effect on drug release markedly. Glidant-containing formulations showed a delayed deformation and damage of the ethyl cellulose-coated pellet upon mechanical stress. In summary, cushion layer based on microcrystalline cellulose facilitated segregation-free compression of a highly compression-sensitive extended release ethyl cellulose-coated pellets into fast-disintegrating and hard tablets without compromising the release properties of the multiparticulates. Directly compressible cushion-layered pellets protected the pellet coating significantly better from damages during tabletting when compared to the conventional compression of blends of coated pellets and excipient powders. PMID:23892153

  15. Analysis of whole-body vibration during manual wheelchair propulsion: a comparison of seat cushions and back supports for individuals without a disability.

    PubMed

    DiGiovine, Carmen P; Cooper, Rory A; Wolf, Erik; Fitzgerald, Shirley G; Boninger, Michael L

    2003-01-01

    Whole-body vibration exposure has been found to be detrimental to the health of humans owing to effects such as degraded comfort, disc degeneration, and lower back pain. The purpose of this study was to determine if selected seat cushions and back supports minimize the transmission of vibrations during manual wheelchair propulsion. Ten unimpaired participants traversed an activities of daily living course using four seat cushions and four back supports. Vibrations were measured using triaxial accelerometers. The time domain and frequency domain transmissibility was used to determine if differences exist among seat cushions and back supports. Differences were found among the four seat cushions and four back supports. Seat cushion and back support manufacturers should concentrate on single-event shocks and repeated shocks, as opposed to oscillatory motions and self-generated vibrations, because the vibrations generated by these events tend to reside in the range of frequencies most sensitive to humans. Vibrations in this range of frequencies have the greatest effect on the transmission of whole-body vibration during manual wheelchair propulsion. Differences among the seat cushions and back supports appear to be due to the seat cushion/back support design and postural support. From a clinical perspective, the time domain transmissibility best describes the transmission of whole-body vibration. PMID:15137730

  16. An adaptive dual-optimal path-planning technique for unmanned air vehicles with application to solar-regenerative high altitude long endurance flight

    NASA Astrophysics Data System (ADS)

    Whitfield, Clifford A.

    2009-12-01

    A multi-objective technique for Unmanned Air Vehicle (UAV) path and trajectory autonomy generation, through task allocation and sensor fusion has been developed. The Dual-Optimal Path-Planning (D-O.P-P.) Technique generates on-line adaptive flight paths for UAVs based on available flight windows and environmental influenced objectives. The environmental influenced optimal condition, known as the driver' determines the condition, within a downstream virtual window of possible vehicle destinations and orientation built from the UAV kinematics. The intermittent results are pursued by a dynamic optimization technique to determine the flight path. This sequential optimization technique is a multi-objective optimization procedure consisting of two goals, without requiring additional information to combine the conflicting objectives into a single-objective. An example case-study and additional applications are developed and the results are discussed; including the application to the field of Solar Regenerative (SR) High Altitude Long Endurance (HALE) UAV flight. Harnessing solar energy has recently been adapted for use on high altitude UAV platforms. An aircraft that uses solar panels and powered by the sun during the day and through the night by SR systems, in principle could sustain flight for weeks or months. The requirements and limitations of solar powered flight were determined. The SR-HALE UAV platform geometry and flight characteristics were selected from an existing aircraft that has demonstrated the capability for sustained flight through flight tests. The goals were to maintain continual Situational Awareness (SA) over a case-study selected Area of Interest (AOI) and existing UAV power and surveillance systems. This was done for still wind and constant wind conditions at altitude along with variations in latitude. The characteristics of solar flux and the dependence on the surface location and orientation were established along with fixed flight maneuvers for the SR-HALE UAV. A sustained turn circle flight pattern, common for vehicles in loiter was selected as a baseline for comparisons. The objectives of the D-O.P-P. Technique for SR-HALE flight were to determine the minimum required power flight paths to the predetermined location and orientation for obtaining maximum solar flux established by the 'driver.' The on-line path generation technique prolonged the flight duration, over the baseline by approximately two months for a year of flight over the case-study AOI. This prolonged flight was consistent for all latitude locations, including two months of available flight at 60 degree latitude---where sustained turn baseline flight was no longer capable. This was possible by increasing the total solar power by as much as 28% while decreasing the averaged power required for flight.

  17. 20/07/2011 09:30Will male cottony cushion scales survive their own mating strategy? | Molecular Love (and other facts of life) Page 1 of 3http://nittygrittyscience.com/2011/07/19/will-male-cottony-cushion-...=will-male-cottony-cushion-scales-survive-their

    E-print Network

    Gardner, Andy

    Love (and other facts of life) Page 1 of 3http://nittygrittyscience.com/2011/07/19/will-male-cottony genes with those mates. Because the eggs he's fertilizing are from his daughter, Molecular Love (and cottony cushion scales survive their own mating strategy? | Molecular Love (and other facts of life) Page

  18. Launch vehicle effluent measurements during the May 12, 1977, Titan 3 launch at Air Force Eastern Test Range

    NASA Technical Reports Server (NTRS)

    Gregory, G. L.; Bendura, R. J.; Woods, D. C.

    1979-01-01

    Airborne effluent measurements and cloud physical behavior for the May 21, 1977, Titan 3 launch from the Air Force Eastern Test Range, Fla. are presented. The monitoring program included airborne effluent measurements in situ in the launch cloud, visible and infrared photography of cloud growth and physical behavior, and limited surface collection of rain samples. Airborne effluent measurements included concentrations of HCl, NO, NOx, and aerosols as a function of time in the exhaust cloud. For the first time in situ particulate mass concentration and aerosol number density were measured as a function of time and size in the size range of 0.05 to 25 micro meters diameter. Measurement results were similar to those of earlier launch monitorings. Maximum HCl and NOx concentrations ranged from 10 ppm and 500 ppb, respectively, several minutes after launch to about 1 ppm and 100 ppb at 45 minutes after launch.

  19. Intake fractions of primary conserved air pollutants emitted from on-road vehicles in the United States

    NASA Astrophysics Data System (ADS)

    Lobscheid, Agnes B.; Nazaroff, William W.; Spears, Michael; Horvath, Arpad; McKone, Thomas E.

    2012-12-01

    Vehicular air pollutant emissions are characterized by a high degree of spatial variability that is correlated with the distribution of people. The consequences of the spatial association between emissions and exposed populations have not been fully captured in lifecycle and other impact assessments. The intake fraction (iF) quantifies aggregate air-pollutant exposures attributable to sources. Utilizing source-receptor (S-R) relationships derived from the US Environmental Protection Agency's AERMOD steady-state plume model, we quantify the intake fraction of conserved pollutants emitted from on-road mobile sources and report here the first characterization across approximately 65,000 census tracts of the conterminous United States. Considering exposures out to 50 km from the source, the population-weighted mean iF is 8.6 parts per million (ppm). The population-weighted median generally increases with geographic scale, from 3.6 ppm for census tracts to 4.2 ppm for counties, and 5.1 ppm for states, while the population-weighted interquartile range (IQR) progressively narrows as geographic scale increases: 0.85-8.8 ppm for census tracts, 1.5-8.5 ppm for counties, and 3.2-7.5 ppm for states. Across the four US Census regions, the population weighted median iF varies from 2.2 ppm (South) to 7.5 ppm (West), and the census-tract IQR spans an order of magnitude in each region (2.1-17 ppm in the West; 0.55-6.9 ppm in the Midwest; 0.45-5.5 ppm in the South; and 1.8-18 ppm in the Northeast). The population-weighted mean intake fraction for populous urban counties is about two orders of magnitude greater than for sparsely populated rural counties. On a population-weighted average basis and considering the 50 km analysis range, 75% of the intake occurs in the same county as emissions.

  20. Friction of composite cushion bearings for total knee joint replacements under adverse lubrication conditions.

    PubMed

    Stewart, T; Jin, Z M; Fisher, J

    1997-01-01

    Conventional joint replacements consist of a polished metallic or ceramic component articulating against a layer of polyethylene. Although the friction in the contact between these articulating surfaces is low, polyethylene wear is produced as a result of a boundary/mixed lubrication regime. Wear debris is generated by direct asperity contact, abrasion, adhesion and fatigue, and has been shown to cause adverse tissue reactions which can lead to joint failure. The introduction of soft compliant materials, similar in stiffness to articular cartilage, has shown that with cyclic loading and relative motion between the articulating surfaces typical of normal walking, a fluid film can be maintained through combined entraining and squeeze-film actions, and hence wear can be minimized. For 95 per cent of the time, however, we are not walking but standing still or moving slowly. A pendulum simulator has been used in the present study to investigate the effect of adverse tribological conditions which may lead to fluid film breakdown, such as severe cyclic loading, particularly in the swing phase, reduced sliding velocity, reduced stroke length and start-up after a period of constant loading. Friction of a model composite cushion knee bearing, manufactured from a graded modulus (20-1000 MPa) layer of polyurethane, sliding against a polished metal cylinder has been measured for various lubricants and the results have been analysed using a Stribeck assessment. Severe cyclic loading, decreased sliding velocity and decreased stroke length have been found to limit the degree of fluid entrainment previously allowed during the swing phase of normal walking, thus allowing breakdown of fluid films and elevated levels of friction and surface damage. Soft layer joint replacements must therefore be designed to operate with thick elastohydrodynamic fluid films to provide some degree of protection when tribological conditions become severe, or alternatively incorporate alternative boundary or mixed lubrication mechanisms. This study quantifies a potential limitation of the cushion bearing concept. PMID:9509883

  1. 40 CFR 86.1822-01 - Durability data vehicle selection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1822-01...

  2. 40 CFR 86.1822-01 - Durability data vehicle selection.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1822-01...

  3. 40 CFR 86.1828-10 - Emission data vehicle selection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1828-10...

  4. 40 CFR 86.1828-10 - Emission data vehicle selection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1828-10...

  5. 40 CFR 86.1807-07 - Vehicle labeling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1807-07...

  6. 40 CFR 86.1828-10 - Emission data vehicle selection.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1828-10...

  7. 40 CFR 86.1822-01 - Durability data vehicle selection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1822-01...

  8. 40 CFR 86.1807-07 - Vehicle labeling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1807-07...

  9. Transportation Center Seminar... Envisioning Autonomous Vehicle Pathways through

    E-print Network

    Bustamante, Fabián E.

    Transportation Center Seminar... Envisioning Autonomous Vehicle Pathways through the Lens of Air Foster St., Evanston Abstract: Autonomous vehicles promise numerous transportation system benefits, from of autonomous vehicle technology showcased by numerous successful tests stands in contrast to the lagging

  10. 40 CFR 86.1828-10 - Emission data vehicle selection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1828-10...

  11. 40 CFR 86.1822-01 - Durability data vehicle selection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1822-01...

  12. 40 CFR 86.1807-07 - Vehicle labeling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1807-07...

  13. An insect-inspired flapping wing micro air vehicle with double wing clap-fling effects and capability of sustained hovering

    NASA Astrophysics Data System (ADS)

    Nguyen, Quoc-Viet; Chan, Woei Leong; Debiasi, Marco

    2015-03-01

    We present our recent flying insect-inspired Flapping-Wing Micro Air Vehicle (FW-MAV) capable of hovering flight which we have recently achieved. The FW-MAV has wing span of 22 cm (wing tip-to-wing tip), weighs about 16.6 grams with onboard integration of radio control system including a radio receiver, an electronic speed control (ESC) for brushless motor, three servos for attitude flight controls of roll, pitch, and yaw, and a single cell lithium-polymer (LiPo) battery (3.7 V). The proposed gear box enables the FW-MAV to use one DC brushless motor to synchronously drive four wings and take advantage of the double clap-and-fling effects during one flapping cycle. Moreover, passive wing rotation is utilized to simplify the design, in addition to passive stabilizing surfaces for flight stability. Powered by a single cell LiPo battery (3.7 V), the FW-MAV flaps at 13.7 Hz and produces an average vertical force or thrust of about 28 grams, which is sufficient for take-off and hovering flight. Finally, free flight tests in terms of vertical take-off, hovering, and manual attitude control flight have been conducted to verify the performance of the FW-MAV.

  14. Experimental characterization of the structural dynamics and aero-structural sensitivity of a hawkmoth wing toward the development of design rules for flapping-wing micro air vehicles

    NASA Astrophysics Data System (ADS)

    Norris, Aaron G.

    A case is made for why the structures discipline must take on a more central role in the research and design of flapping-wing micro micro-air-vehicles, especially if research trends continue toward bio-inspired, insect-sized flexible wing designs. In making the case, the eigenstructure of the wing emerges as a key structural metric for consideration. But with virtually no structural dynamic data available for actual insect wings, both engineered and computational wing models that have been inspired by biological analogs have no structural truth models to which they can be anchored. An experimental framework is therefore developed herein for performing system identification testing on the wings of insects. This framework is then utilized to characterize the structural dynamics of the forewing of a large sample of hawkmoth (Manduca sexta ) for future design and research consideration. The research also weighs-in on a decade-long debate as to the relative contributions that the inertial and fluid dynamic forces acting on a flapping insect wing have on its deformation (expression) during flight. Ultimately the finding proves that both affect wing expression significantly, casting serious doubt on the long-standing and most frequently cited research that indicates fluid dynamic have minimal or negligible effect

  15. Studies on potential emission of hazardous gases due to uncontrolled open-air burning of waste vehicle tyres and their possible impacts on the environment

    NASA Astrophysics Data System (ADS)

    Shakya, Pawan R.; Shrestha, Pratima; Tamrakar, Chirika S.; Bhattarai, Pradeep K.

    Uncontrolled open-air burning of waste vehicle tyres causing environmental pollution has become a popular practice in Nepal despite official ban considering the environment and public health hazards. In this study, an experimental model was set up in a laboratory scale in an attempt to understand the potential emission of hazardous gases such as CO, SO 2 and NO 2 due to such activities in Kathmandu Valley and their possible impacts on the environment. For this purpose, four types of tyre were collected representing two from passenger car and two from motorbike category. The emission level of CO in the tyre smoke was measured with a CO gas detector tube while SO 2 and NO 2 were determined by UV-visible spectrophotometer. Among the three types of the gases analyzed, SO 2 was emitted in significantly high levels by all the representative tyre samples. The emission levels of CO, SO 2 and NO 2 ranged from 21to 49, 102to 820 and 3to 9 ?g g -1, respectively. Results revealed that the emission levels also varied with the tyre types and qualities. The potential emission of the hazardous gases per representative scrap tyre mass was also estimated. Results indicate that the gaseous pollutants due to the tyre fires could make a significant contribution for deterioration of the environmental condition of the Valley or elsewhere.

  16. Abstract--Multi-vehicle applications rely on the dynamic allocation of resources such as vehicles,

    E-print Network

    Sengupta, Raja

    of this model are services and service providers. Services are defined by standard names and interfaces such as unmanned air vehicle networks (see [1]), net markets (see [2]), metropolitan transportation management, in an unmanned air vehicle network, vehicles leave and join the network, routers go up and down, missions start

  17. Testing the Stress-Gradient Hypothesis at the Roof of the World: Effects of the Cushion Plant Thylacospermum caespitosum on Species Assemblages

    PubMed Central

    Dvorský, Miroslav; Doležal, Ji?í; Kopecký, Martin; Chlumská, Zuzana; Janatková, Kate?ina; Altman, Jan; de Bello, Francesco; ?eháková, Klára

    2013-01-01

    Many cushion plants ameliorate the harsh environment they inhabit in alpine ecosystems and act as nurse plants, with significantly more species growing within their canopy than outside. These facilitative interactions seem to increase with the abiotic stress, thus supporting the stress-gradient hypothesis. We tested this prediction by exploring the association pattern of vascular plants with the dominant cushion plant Thylacospermum caespitosum (Caryophyllaceae) in the arid Trans-Himalaya, where vascular plants occur at one of the highest worldwide elevational limits. We compared plant composition between 1112 pair-plots placed both inside cushions and in surrounding open areas, in communities from cold steppes to subnival zones along two elevational gradients (East Karakoram: 4850–5250 m and Little Tibet: 5350–5850 m). We used PERMANOVA to assess differences in species composition, Friedman-based permutation tests to determine individual species habitat preferences, species-area curves to assess whether interactions are size-dependent and competitive intensity and importance indices to evaluate plant-plant interactions. No indications for net facilitation were found along the elevation gradients. The open areas were not only richer in species, but not a single species preferred to grow exclusively inside cushions, while 39–60% of 56 species detected had a significant preference for the habitat outside cushions. Across the entire elevation range of T. caespitosum, the number and abundance of species were greater outside cushions, suggesting that competitive rather than facilitative interactions prevail. This was supported by lower soil nutrient contents inside cushions, indicating a resource preemption, and little thermal amelioration at the extreme end of the elevational gradient. We attribute the negative associations to competition for limited resources, a strong environmental filter in arid high-mountain environment selecting the stress-tolerant species that do not rely on help from other plants during their life cycle and to the fact the cushions do not provide a better microhabitat to grow in. PMID:23326446

  18. A mixed simulation and hardware-in-the-loop display and controller for autonomous sensing and navigation by unmanned air vehicles

    NASA Astrophysics Data System (ADS)

    Collins, Gaemus E.; Vegdahl, Philip S.; Riehl, James R.

    2007-04-01

    This paper describes our recent work combining a high-fidelity battlefield software simulaton, a suite of autonomous sensor and navigation control algorithms for unmanned air vehicles (UAVs), and a hardware-in-the-loop control interface. The complete system supports multiple real and simulated UAVs that search for and track multiple real and simulated targets. Targets communicate their real-time locations to the simulator through a wireless GPS link. Data from real target(s) is used to create target(s) in the simulation testbed that may exist alongside additional simulated targets. The navigation and video sensors onboard the UAVs are tasked (via another wireless link) by our control algorithm suite to search for and track targets that exist in the simulation. Video data is streamed to an image plane video tracker (IPVT), which produces detections that can be fed to a global tracker within the control suite. Routing and gimbal control algorithms use information from the global tracker to task the UAVs, thus completing an information feedback control loop. Additional sensors (such as the ground moving target indicator (GMTI) radar) can exist within the simulation and generate simulated detections to augment the tracking information obtained from the IPVT. Our simulator is part of Toyon's Simulation of the Locations and Attack of Mobile Enemy Missiles (SLAMEM (R)) tool. SLAMEM contains detailed models for ground targets, surveillance platforms, sensors, attack aircraft, UAVs, data exploitation, multi-source fusion, sensor retasking, and attack nomination. SLAMEM models road networks, foliage cover, populated regions, and terrain, using the terrain elevation data (DTED).

  19. Spatial transcriptional profile of the chick and mouse endocardial cushions identify novel regulators of endocardial EMT in vitro.

    PubMed

    DeLaughter, Daniel M; Christodoulou, Danos C; Robinson, Jamille Y; Seidman, Christine E; Baldwin, H Scott; Seidman, J G; Barnett, Joey V

    2013-06-01

    Valvular Interstitial Cells (VICs) are a common substrate for congenital and adult heart disease yet the signaling mechanisms governing their formation during early valvulogenesis are incompletely understood. We developed an unbiased strategy to identify genes important in endocardial epithelial-to-mesenchymal transformation (EMT) using a spatial transcriptional profile. Endocardial cells overlaying the cushions of the atrioventricular canal (AVC) and outflow tract (OFT) undergo an EMT to yield VICs. RNA sequencing (RNA-seq) analysis of gene expression between AVC, OFT, and ventricles (VEN) isolated from chick and mouse embryos at comparable stages of development (chick HH18; mouse E11.0) was performed. EMT occurs in the AVC and OFT cushions, but not VEN at this time. 198 genes in the chick (n=1) and 105 genes in the mouse (n=2) were enriched 2-fold in the cushions. Gene regulatory networks (GRN) generated from cushion-enriched gene lists confirmed TGF? as a nodal point and identified NF-?B as a potential node. To reveal previously unrecognized regulators of EMT four candidate genes, Hapln1, Id1, Foxp2, and Meis2, and a candidate pathway, NF-?B, were selected. In vivo spatial expression of each gene was confirmed by in situ hybridization and a functional role for each in endocardial EMT was determined by siRNA knockdown in a collagen gel assay. Our spatial-transcriptional profiling strategy yielded gene lists which reflected the known biology of the system. Further analysis accurately identified and validated previously unrecognized novel candidate genes and the NF-?B pathway as regulators of endocardial cell EMT in vitro. PMID:23557753

  20. Structural sandwich construction is used in many air and space vehicles, cargo containers, boats and ships. Connection of the sandwich construction component to a framework or substructure

    E-print Network

    Vel, Senthil

    , boats and ships. Connection of the sandwich construction component to a framework or substructure vehicles, ships, boats, cargo containers and residential construction. Sandwich construction provide

  1. Electrohydraulic vehicle drive system

    SciTech Connect

    Gardner, E.W. Jr.

    1988-06-28

    A power system is described for a vehicle comprising: a battery source for driving a DC electric motor mechanically coupled to a fluid pump which pressurizes a fluid for actuating a fluid motor that is operatively connected to reciprocate a worm screw gear assembly which rotates an output shaft connected to axles which drive the wheels of a vehicle, an auxiliary power device for operating an alternator to generate electricity and means for recovering kinetic energy. The auxiliary power device includes means for supplying compressed air or steam to an air or steam motor which is operatively connected to a second worm screw gear assembly which drives an output shaft connected to the alternator for generating electricity, and wherein the kinetic energy recovery means includes an air pump connected between the axles and frame of the vehicle chassis so that vehicular movement actuates the air pump for compressing air for storage and also a worm screw gear driven alternator assembly connected between the axle and frame of the vehicle chassis for generating electricity during vehicular movement.

  2. Path Planning Algorithms for Multiple Heterogeneous Vehicles 

    E-print Network

    Oberlin, Paul V.

    2010-01-16

    as the \\Precedence Constrained Asymmetric Travelling Salesman Problem" (PCATSP). v ACKNOWLEDGMENTS Special thanks to the Air Force Research Laboratory (AFRL) Air Vehicles Direc- torate for providing funding and motivation for portions of this thesis, Waqar Malik...

  3. Molecular analysis of the nondisjoined chromosome in trisomy 21 with and without endocardial cushion defects

    SciTech Connect

    Zittergruen, M.M.; Murray, J.C.; Lauer, R.M. [Univ. of Iowa, Iowa City, IA (United States)] [and others

    1994-09-01

    Congenital heart disease is found in approximately 40% of patients with Down syndrome (DS), with endocardial cushion defects (ECDs) comprising one-third of the defects. Sixteen highly polymorphic microsatellite markers were typed in two groups (Group 1: DS with ECD, n=43, and Group 2: DS without ECD, n=52) to determine: (1) the parental origin of the extra chromosome, (2) the presence or absence of disomic homozygosity (reduced) or heterozygosity (nonreduced) of the markers along 21q, and (3) the presence or absence of recombination in the nondisjoined chromosome. The association of these three factors with the presence of ECD in DS was then determined. The origin of the nondisjoined chromosome was maternal in 86.3% of the total cases with no significant differences between groups 1 and 2. The most centromeric marker was nonreduced in 77% of the maternally-derived trisomies (indicative of a meiosis II nondisjunction) with no significant differences between groups 1 and 2. The most telomeric markers showed no differences in the number of reduced or nonreduced markers between maternally and paternally derived chromosomes or between groups 1 and 2. Recombination was significantly decreased in group 1 (28%) compared to group 2 (56%) (chi-square 7.45, p < 0.01) with similar values for both paternally and maternally-derived trisomies. Overall, recombination was present in 43.2% of the nondisjoined chromosomes which is similar to the 42.3% recombination reported in nondisjoined chromosomes in trisomy 21.

  4. A nanometric cushion for enhancing scratch and wear resistance of hard films.

    PubMed

    Gotlib-Vainshtein, Katya; Girshevitz, Olga; Sukenik, Chaim N; Barlam, David; Cohen, Sidney R

    2014-01-01

    Scratch resistance and friction are core properties which define the tribological characteristics of materials. Attempts to optimize these quantities at solid surfaces are the subject of intense technological interest. The capability to modulate these surface properties while preserving both the bulk properties of the materials and a well-defined, constant chemical composition of the surface is particularly attractive. We report herein the use of a soft, flexible underlayer to control the scratch resistance of oxide surfaces. Titania films of several nm thickness are coated onto substrates of silicon, kapton, polycarbonate, and polydimethylsiloxane (PDMS). The scratch resistance measured by scanning force microscopy is found to be substrate dependent, diminishing in the order PDMS, kapton/polycarbonate, Si/SiO2. Furthermore, when PDMS is applied as an intermediate layer between a harder substrate and titania, marked improvement in the scratch resistance is achieved. This is shown by quantitative wear tests for silicon or kapton, by coating these substrates with PDMS which is subsequently capped by a titania layer, resulting in enhanced scratch/wear resistance. The physical basis of this effect is explored by means of Finite Element Analysis, and we suggest a model for friction reduction based on the "cushioning effect" of a soft intermediate layer. PMID:25161836

  5. Sensitivity of urban airshed model results for test fuels to uncertainties in light-duty vehicle and biogenic emissions and alternative chemical mechanisms—Auto/oil air quality improvement research program

    NASA Astrophysics Data System (ADS)

    Chock, David P.; Yarwood, Greg; Dunker, Alan M.; Morris, Ralph E.; Pollack, Alison K.; Schleyer, Charles H.

    Three sources of uncertainty in the air quality modeling performed for the Auto/Oil Air Quality Improvement: Research Program, Phase I, were investigated to assess their impact on predicted ozone for test fuels in Los Angeles in year 2010. First, quadrupling the estimated total organic gas (TOG) and tripling the CO emissions from light-duty gasoline vehicles in the air quality model increases the predicted peak ozone, as expected. The percent increase in peak ozone for the test fuels, about 25% of total ozone, is essentially the same as the percent increase in TOG emissions, about 25% of the total emissions from all sources. However, there is no important effect on the ranking of the test fuels from lowest to highest in predicted ozone formation. Second, replacing the original biogenic emission inventory with an alternative inventory having substantially lower biogenic emissions reduces the predicted peak ozone. The percent decrease in peak ozone, about 6% of total ozone, is considerably less than the percent decrease in TOG emissions, about 34% of total emissions. Fuel rankings are unchanged except for a reversal of two test gasolines in the ranking based on peak ozone. However, this reversal is not found in fuel rankings based on other measures of ozone formation. Third, replacing the Carbon Bond Mechanism version IV (CBM-IV) in the air quality model with an alternative representation of atmospheric chemistry, the Statewide Air Pollution Research Center (SAPRC) mechanism, increases the peak ozone by about 9%. There are also important changes in fuel rankings. For one research test gasoline, the contribution of light-duty gasoline vehicles to ozone is similar with both chemical mechanisms, but for another test gasoline that gives the lowest ozone with the CBM-IV, the contribution of light-duty gasoline vehicles to ozone is substantially higher with the SAPRC mechanism. With the CBM-IV mechanism, the most promising of the test gasolines studied has lower predicted ozone than any of the cases representing use of methanol fuels in prototype, flexible/variable fuel vehicles. With the SAPRC mechanism, the most promising test gasoline studied has lower predicted ozone than one methanol case and higher ozone than the other methanol case. These changes in fuel rankings are probably due to known differences in the reactivity of toluene and formaldehyde in the two mechanisms.

  6. DBD Plasma Actuators for Flow Control in Air Vehicles and Jet Engines - Simulation of Flight Conditions in Test Chambers by Density Matching

    NASA Technical Reports Server (NTRS)

    Ashpis, David E.; Thurman, Douglas R.

    2011-01-01

    Dielectric Barrier Discharge (DBD) Plasma actuators for active flow control in aircraft and jet engines need to be tested in the laboratory to characterize their performance at flight operating conditions. DBD plasma actuators generate a wall-jet electronically by creating weakly ionized plasma, therefore their performance is affected by gas discharge properties, which, in turn, depend on the pressure and temperature at the actuator placement location. Characterization of actuators is initially performed in a laboratory chamber without external flow. The pressure and temperature at the actuator flight operation conditions need to be simultaneously set in the chamber. A simplified approach is desired. It is assumed that the plasma discharge depends only on the gas density, while other temperature effects are assumed to be negligible. Therefore, tests can be performed at room temperature with chamber pressure set to yield the same density as in operating flight conditions. The needed chamber pressures are shown for altitude flight of an air vehicle and for jet engines at sea-level takeoff and altitude cruise conditions. Atmospheric flight conditions are calculated from standard atmosphere with and without shock waves. The engine data was obtained from four generic engine models; 300-, 150-, and 50-passenger (PAX) aircraft engines, and a military jet-fighter engine. The static and total pressure, temperature, and density distributions along the engine were calculated for sea-level takeoff and for altitude cruise conditions. The corresponding chamber pressures needed to test the actuators were calculated. The results show that, to simulate engine component flows at in-flight conditions, plasma actuator should be tested over a wide range of pressures. For the four model engines the range is from 12.4 to 0.03 atm, depending on the placement of the actuator in the engine. For example, if a DBD plasma actuator is to be placed at the compressor exit of a 300 PAX engine, it has to be tested at 12.4 atm for takeoff, and 6 atm for cruise conditions. If it is to be placed at the low-pressure turbine, it has to be tested at 0.5 and 0.2 atm, respectively. These results have implications for the feasibility and design of DBD plasma actuators for jet engine flow control applications. In addition, the distributions of unit Reynolds number, Mach number, and velocity along the engine are provided. The engine models are non-proprietary and this information can be used for evaluation of other types of actuators and for other purposes.

  7. Nitrous oxide emissions from light duty vehicles

    Microsoft Academic Search

    Lisa A. Graham; Sheri L. Belisle; Paul Rieger

    2009-01-01

    Nitrous oxide (N2O) emissions measurements were made on light duty gasoline and light duty diesel vehicles during chassis dynamometer testing conducted at the Environment Canada and California Air Resources Board vehicle emissions laboratories between 2001 and 2007. Per phase and composite FTP emission rates were measured. A subset of vehicles was also tested using other driving cycles to characterize emissions

  8. Comparison of Vehicle Activity and Emission Inventory between Beijing and Shanghai

    Microsoft Academic Search

    Huan Liu; Kebin He; Qidong Wang; Hong Huo; James Lents; Nicole Davis; Nick Nikkila; Changhong Chen; Mauricio Osses; Chunyu He; Yasuko Yoshida; Azusa Ito; Masashi Murakami; Takayuki Murakami; Hideharu Fujimoto; Kikuo Takeda; Shigeru Suzuki; Masahiro Hori; Thomas Hilber; Michalis Agraniotis; Panagiotis Grammelis; Emmanuel Kakaras; Thomas Glorius; Uwe Becker; Willy Derichs; Hans-Peter Schiffer; Martin Jong; Lucia Torri; Glynis Lough; Charles Christensen; James Schauer; James Tortorelli; Erin Mani; Douglas Lawson; Nigel Clark; Peter Gabele; Aki Virkkula; Timo; Risto Hillamo; Tarja Yli-Tuomi; Anne Hirsikko; Ismo Koponen; Nicholas Doll; John Reisel; Aro´n Jazcilevich; Alejandro Garcý´a-Fragoso; Agustý´n Reynoso; Michel Grutter; Ulises Diego-Ayala; Igor Burstyn; Ambikaipakan Senthilselvan; Hyang-Mi Kim; Nicola Cherry; Elise Pietroniro; Cheryl Waldner; Delbert Eatough; Nolan Mangelson; Richard Anderson; Donald Martello; Natalie Pekney; Cliff Davidson; William Modey

    2007-01-01

    Vehicle emission inventory is a critical element for air quality study. This study created systemic methods to establish a vehicle emission inventory in Chinese cities. The methods were used to obtain credible results of vehicle activity in Beijing and Shanghai. On the basis of the vehicle activity data, the International Vehicle Emission model is used to establish vehicle emission inventories.

  9. Subjective valuation of cushioning in a human drop landing task as quantified by trade-offs in mechanical work.

    PubMed

    Skinner, Nathaniel E; Zelik, Karl E; Kuo, Arthur D

    2015-07-16

    Humans can perform motor tasks in a variety of ways, yet often favor a particular strategy. Some factors governing the preferred strategy may be objective and quantifiable, (e.g. metabolic energy or mechanical work) while others may be more subjective and less measurable, (e.g. discomfort, pain, or mental effort). Subjectivity can make it challenging to explain or predict preferred movement strategies. We propose that subjective factors might nevertheless be characterized indirectly by their trade-offs against more objective measures such as work. Here we investigated whether subjective costs that influence human movement during drop landings could be indirectly assessed by quantifying mechanical work performed. When landing on rigid ground, humans typically absorb much of the collision actively by bending their knees, perhaps to avoid the discomfort of stiff-legged landings. We measured how work performed by healthy adults (N=8) changed as a function of surface cushioning for drop landings (fixed at about 0.4m) onto varying amounts of foam. Landing on more foam dissipated more energy passively in the surface, thus reducing the net dissipation required of subjects, due to relatively fixed landing energy. However, subjects actually performed even less work in the dissipative collision, as well as in the subsequent active, positive work to return to upright stance (approximately linear decrease of about 1.52J per 1cm of foam thickness). As foam thickness increased, there was also a corresponding reduction in center-of-mass vertical displacement after initial impact by up to 43%. Humans appear to subjectively value cushioning, revealed by the extra work they perform landing without it. Cushioning is thus worth more than the energy it dissipates, in an amount that indicates the subjective discomfort of stiff landings. PMID:25979381

  10. Air bag restraint device

    DOEpatents

    Marts, D.J.; Richardson, J.G.

    1995-10-17

    A rear-seat air bag restraint device is disclosed that prevents an individual, or individuals, from continuing violent actions while being transported in a patrol vehicle`s rear seat without requiring immediate physical contact by the law enforcement officer. The air bag is activated by a control switch in the front seat and inflates to independently restrict the amount of physical activity occurring in the rear seat of the vehicle while allowing the officer to safely stop the vehicle. The air bag can also provide the officer additional time to get backup personnel to aid him if the situation warrants it. The bag is inflated and maintains a constant pressure by an air pump. 8 figs.

  11. Evaluating Cognitive Architectures for Intelligent and Autonomous Unmanned Vehicles

    E-print Network

    Evaluating Cognitive Architectures for Intelligent and Autonomous Unmanned Vehicles Lyle N. Long@psu.edu and sdh187@psu.edu Introduction Unmanned vehicles (air-, ground-, and sea-based), or mobile robots, have and autonomy are important for these vehicles and their continued success. Many of these vehicles, however

  12. Integrated Air/Ground Vehicle System for Semi-Autonomous Off-Road Navigation Tony Stentz (Carnegie Mellon University); axs@cmu.edu

    E-print Network

    Kelly, Alonzo

    addressing the Robotics Supporting Technology area of the US Army's Future Combat System (FCS). The Percept pursuing semi-autonomous vehicle systems in the Future Combat Systems (FCS) program. FCS places high-Road Mobility (PerceptOR) Program Team Blitz, consisting of the National Robotics Engineering Consortium

  13. Experimental Aeroheating Study of Mid-L/D Entry Vehicle Geometries: NASA LaRC 20-Inch Mach 6 Air Tunnel Test 6966

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Hollingsworth, Kevin E.

    2014-01-01

    Aeroheating data on mid lift-to-drag ratio entry vehicle configurations has been obtained through hypersonic wind tunnel testing. Vehicles of this class have been proposed for high-mass Mars missions, such as sample return and crewed exploration, for which the conventional sphere-cone entry vehicle geometries of previous Mars missions are insufficient. Several configurations were investigated, including elliptically-blunted cylinders with both circular and elliptical cross sections, biconic geometries based on launch vehicle dual-use shrouds, and parametrically-optimized analytic geometries. Testing was conducted at Mach 6 over a range of Reynolds numbers sufficient to generate laminar, transitional, and turbulent flow. Global aeroheating data were obtained using phosphor thermography. Both stream-wise and cross-flow transition occured on different configurations. Comparisons were made with laminar and turbulent computational predictions generated with an algebraic turbulence model. Predictions were generally in good agreement in regions of laminar or fully-turbulent flow; however for transitional cases, the lack of a transition onset prediction capability produced less accurate comparisons. The data obtained in this study are intended to be used for prelimary mission design studies and the development and validation of computational methods.

  14. 40 CFR Appendix I to Subpart S of... - Vehicle Procurement Methodology

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles Pt. 86, Subpt. S,...

  15. 40 CFR 86.1836-01 - Manufacturer-supplied production vehicles for testing.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1836-01...

  16. 40 CFR 86.1817-05 - Complete heavy-duty vehicle averaging, trading, and banking program.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1817-05...

  17. 40 CFR 86.1817-08 - Complete heavy-duty vehicle averaging, trading, and banking program.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1817-08...

  18. 40 CFR Appendix I to Subpart S of... - Vehicle Procurement Methodology

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles Pt. 86, Subpt. S,...

  19. 40 CFR 86.1817-05 - Complete heavy-duty vehicle averaging, trading, and banking program.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1817-05...

  20. 40 CFR 86.1836-01 - Manufacturer-supplied production vehicles for testing.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1836-01...

  1. 40 CFR Appendix I to Subpart S of... - Vehicle Procurement Methodology

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles Pt. 86, Subpt. S,...

  2. 40 CFR 86.1817-08 - Complete heavy-duty vehicle averaging, trading, and banking program.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1817-08...

  3. 40 CFR 86.1863-07 - Chassis certification for diesel vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1863-07...

  4. 40 CFR 86.1831-01 - Mileage accumulation requirements for test vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1831-01...

  5. 40 CFR 86.1817-08 - Complete heavy-duty vehicle averaging, trading, and banking program.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1817-08...

  6. 40 CFR 86.1831-01 - Mileage accumulation requirements for test vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1831-01...

  7. 40 CFR 86.1863-07 - Chassis certification for diesel vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1863-07...

  8. 40 CFR 86.1836-01 - Manufacturer-supplied production vehicles for testing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1836-01...

  9. 40 CFR 86.1831-01 - Mileage accumulation requirements for test vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1831-01...

  10. 40 CFR 86.1863-07 - Optional chassis certification for diesel vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1863-07...

  11. 40 CFR 86.1817-05 - Complete heavy-duty vehicle averaging, trading, and banking program.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1817-05...

  12. 49 CFR 176.93 - Vehicles having refrigerating or heating equipment.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...transport vehicles having refrigerating or heating equipment operated by internal combustion engines which will permit ready diffusion of exhaust gases to the open air. Passenger vehicles may not be stowed in a position adjacent to vehicles operating...

  13. 40 CFR 85.1715 - Aircraft meeting the definition of motor vehicle.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...CONTROL OF AIR POLLUTION FROM MOBILE SOURCES Exclusion and Exemption of Motor Vehicles and Motor Vehicle Engines § 85.1715 Aircraft meeting the definition of motor vehicle. This section applies for aircraft meeting the definition of motor...

  14. 40 CFR 85.1715 - Aircraft meeting the definition of motor vehicle.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...CONTROL OF AIR POLLUTION FROM MOBILE SOURCES Exclusion and Exemption of Motor Vehicles and Motor Vehicle Engines § 85.1715 Aircraft meeting the definition of motor vehicle. This section applies for aircraft meeting the definition of motor...

  15. 40 CFR 86.1817-05 - Complete heavy-duty vehicle averaging, trading, and banking program.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1817-05...

  16. 40 CFR 86.1831-01 - Mileage accumulation requirements for test vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1831-01...

  17. 40 CFR 86.1836-01 - Manufacturer-supplied production vehicles for testing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1836-01...

  18. 40 CFR 86.1863-07 - Optional chassis certification for diesel vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1863-07...

  19. 40 CFR Appendix I to Subpart S of... - Vehicle Procurement Methodology

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles Pt. 86, Subpt. S,...

  20. 40 CFR 86.1817-08 - Complete heavy-duty vehicle averaging, trading, and banking program.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1817-08...

  1. 40 CFR 69.51 - Motor vehicle diesel fuel.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Motor vehicle diesel fuel. 69.51 Section 69.51 Protection of Environment ENVIRONMENTAL...THE CLEAN AIR ACT Alaska § 69.51 Motor vehicle diesel fuel. (a) Definitions. (1) Areas accessible by the Federal Aid...

  2. 40 CFR 69.51 - Motor vehicle diesel fuel.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Motor vehicle diesel fuel. 69.51 Section 69.51 Protection of Environment ENVIRONMENTAL...THE CLEAN AIR ACT Alaska § 69.51 Motor vehicle diesel fuel. (a) Definitions. (1) Areas accessible by the Federal Aid...

  3. 40 CFR 69.51 - Motor vehicle diesel fuel.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Motor vehicle diesel fuel. 69.51 Section 69.51 Protection of Environment ENVIRONMENTAL...THE CLEAN AIR ACT Alaska § 69.51 Motor vehicle diesel fuel. (a) Definitions. (1) Areas accessible by the Federal Aid...

  4. 40 CFR 69.51 - Motor vehicle diesel fuel.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Motor vehicle diesel fuel. 69.51 Section 69.51 Protection of Environment ENVIRONMENTAL...THE CLEAN AIR ACT Alaska § 69.51 Motor vehicle diesel fuel. (a) Definitions. (1) Areas accessible by the Federal Aid...

  5. 40 CFR 69.51 - Motor vehicle diesel fuel.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Motor vehicle diesel fuel. 69.51 Section 69.51 Protection of Environment ENVIRONMENTAL...THE CLEAN AIR ACT Alaska § 69.51 Motor vehicle diesel fuel. (a) Definitions. (1) Areas accessible by the Federal Aid...

  6. Motor vehicle

    SciTech Connect

    Furukawa, Y.; Sano, S.

    1986-04-15

    An improvement in a motor vehicle is described including: a vehicle body; a front road wheel disposed in the front part of the vehicle body; a rear road wheel disposed in the rear part of the vehicle body; an engine for driving at least either of the front and rear road wheels; and a steering wheel for steering at least either of the front and rear road wheels; comprising: detection means connected to the vehicle for detecting the transverse sliding angle of the vehicle body; and display means connected to the detection means for visually displaying the moving direction of the vehicle body on the basis of an output of the detection means; and the detection means comprises a first sensor for detecting the advancing speed of the vehicle, a second sensor for detecting the transverse acceleration of the vehicle, a third sensor for detecting the yawing velocity of the vehicle, and a processor for calculating the transverse sliding angle on the basis of the advancing speed, the transverse acceleration and the yawing velocity.

  7. Down to the Meter: Localized Vehicle Pollution Matters Down to the Meter: Localized Vehicle Pollution Matters

    Microsoft Academic Search

    DOUGLAS HOUSTON; JUN WU; PAUL ONG; ARTHUR WINER

    many aspects of regional air quality over the past thirty years despite tremen- dous growth in both population and vehicle-miles traveled. However, regional strategies to confront vehicle-related pollution are proving to be insufficient to protect the health of those who live, work, attend school, or play near major roadways. Recent air pollution and epidemiological findings suggest that harmful vehicle-related pollutants

  8. Extracellular Matrix Protein Fibulin-2 Is Expressed in the Embryonic Endocardial Cushion Tissue and Is a Prominent Component of Valves in Adult Heart

    Microsoft Academic Search

    Hong-Yan Zhang; Mon-Li Chu; Te-Cheng Pan; Takako Sasaki; Rupert Timpl; Peter Ekblom

    1995-01-01

    Fibulins-1 and -2 are two recently characterized extracellular matrix proteins of a novel protein family. They are found in many tissues in the adult stage, but several differences in their expression patterns were noted in cultured cells and adult tissues. Fibulin-1 is particularly well expressed in the endocardial cushion tissue (ECT) during embryogenesis and we therefore compared the expression patterns

  9. Structure control of poly(p-phenylene vinylene) in layer-by-layer films by deposition on a charged poly(o-methoxyaniline) cushion

    NASA Astrophysics Data System (ADS)

    Marletta, Alexandre; Curcino da Silva, Silésia de Fátima; Piovesan, Erick; Campos, K. R.; Santos Silva, Hugo; de Souza, N. C.; Letícia Vega, Maria; Raposo, Maria; Constantino, Carlos J. L.; Silva, Raigna A.; Oliveira, Osvaldo N.

    2013-04-01

    In this paper, we demonstrate that the intrinsic electric field created by a poly(o-methoxyaniline) (POMA) cushion layer hinders the changes in molecular conformation of poly(p-phenylenevinylene) (PPV) in layer-by-layer with dodecylbenzene sulfonic acid (DBS). This was modeled with density functional theory (DFT) calculations where an energy barrier hampered molecular movements of PPV segments when they were subjected to an electric field comparable to that caused by a charged POMA layer. With restricted changes in molecular conformation, the PPV film exhibited Franck-Condon transitions and the photoexcitation spectra resembled the absorption spectra, in contrast to PPV/DBS films deposited directly on glass, with no POMA cushion. Other effects from the POMA cushion were the reduced number of structural defects, confirmed with Raman spectroscopy, and an enhanced PPV emission at high temperatures (300 K) in comparison with the films on bare glass. The positive effects from the POMA cushion may be exploited for enhanced opto-electronic devices, especially as the intrinsic electric field may assist in separating photoexcited electron-hole pairs in photovoltaic devices.

  10. A prospective, longitudinal, descriptive study of the effect of a customized wheelchair cushion on clinical variables, satisfaction, and functionality among patients with spinal cord injury.

    PubMed

    Vilchis-Aranguren, Rodrigo; Gayol-Mérida, Diana; Quinzaños-Fresnedo, Jimena; Pérez-Zavala, Ramiro; Galíndez-Novoa, Carmen

    2015-02-01

    The Instituto Nacional de Rehabilitación (Rehabilitation National Institute) (INR) developed a prototype wheelchair cushion (INR cushion) designed to adjust to the anthropometry of the user's ischiogluteal area and prevent pressure ulcer formation while maintaining or promoting functionality. A prospective, longitudinal, descriptive study was conducted from February 2010 to February 2011 to evaluate the effect of using the INR cushion on clinical variables, functionality, and user satisfaction. Sixteen patients were recruited (9 male, 7 female, average age 31.8 [range 22-47] years, average body mass index 25 [range 22-34], average time in a wheelchair 10.1 [range 3-26] years) who met the study protocol inclusion criteria of being pressure ulcer-free for at least 6 months and capable of propulsion and transfer without assistance, chronic spinal cord injury (>2 years), and without chronic-degenerative diseases or cognitive problems. Each participant received the cushion for a 2-month evaluation. Eight clinical variables were assessed: trunk control, posture, spasticity, transfer capacity, comfort, skin reaction, propulsion capacity, and pressure release capacity. The clinical assessment was performed using validated scales and instruments: Modified Ashworth Scale (MAS), Functional Independence Measure™ (FIM), Norton Scale, and assessment of skin reaction. Interface pressures were measured using force sensing array, and participants completed a structured interview to assess user expectation, perceived functionality, perceived quality, and likelihood of recommending the device. Two patients withdrew due to appointment conflicts; of the remaining 14, significant differences between the user's experience with other products and the INR were found with regard to pressure redistribution (P = 0.012); all participants but 1 graded the INR as good in all interview categories. No participants developed a pressure ulcer during the study. The customized cushion was especially functional among patients with incomplete thoracic and cervical injuries, high FIM scores, and moderate levels of activities of daily living. Taller patients (P = 0.01) and patients with higher degrees of spasticity (P = 0.007) were less satisfied with functionality. The results of this study contributed to the redesign process of the cushion. These findings may be useful to establish predictors, both subjective and clinical, for patient utilization of wheelchair cushion use. PMID:25654779

  11. Preliminary Drag and Heat-transfer Data Obtained from Air-launched Cone-cylinder Test Vehicle over Mach Number Range from 1.5 to 5.18

    NASA Technical Reports Server (NTRS)

    Messing, Wesley E; Rabb, Leonard; Disher, John H

    1953-01-01

    An air-launched cone-cylinder test vehicle designed to obtain data at Mach numbers above 4.0 was rocket boosted from a release Mach number of 5.18. The vehicle was launched at an altitude of 35,000 feet and reached peak velocity of 5150 feet per second at 28,500 feet. The total-drag coefficient (based on maximum cross-sectional area) decreased gradually from 0.31 at a Mach number of 1.75 to 0.145 at a Mach number of 5.18, while the Reynold's number (based on body length) increased from 31 x 10 to the 6th power to 107 x 10 to the 6th power. The skin friction coefficients, in general, were slightly lower than Van Driest's theoretical values for similar wall-temperature conditions. Convective heat-transfer coefficients were obtained from a single skin-thermocouple measurement. The maximum wall temperature recorded was 1240 degrees r.

  12. Drug storage temperatures in rescue vehicles.

    PubMed

    DuBois, W C

    2000-04-01

    This study was conducted to determine storage temperatures of drugs carried on rescue vehicles. Recording thermometers were placed inside drug boxes carried on rescue vehicles. Those temperatures were compared with ambient air temperatures, temperatures inside mechanically cooled compartments of the rescue vehicles, and USP-recommended drug storage temperatures. The results indicate that drug storage temperatures in some prehospital rescue vehicles exceed USP guidelines. Mechanical cooling of the storage compartment results in drug storage temperatures within the USP guidelines. Mechanical cooling of drug storage compartments on vehicles is technologically and financially possible. PMID:10729674

  13. Driving force characteristics of 40kW switched reluctance motor for electric vehicle

    Microsoft Academic Search

    K. Watanabe; S. Aida; A. Komatsuzaki; I. Miki

    2007-01-01

    There is a growing interest in an electric vehicle (EV), a hybrid-electric vehicle and a fuel-cell vehicle due to air pollution and exhaustion of fossil fuels. These vehicles use motors to obtain the driving force. Switched reluctance motors (SRMs) have a simple structure, high reliability and low cost. Furthermore, these are desirable features for electric vehicle. Our purpose is conversion

  14. Air Bag Installation

    NASA Technical Reports Server (NTRS)

    2003-01-01

    May 10, 2003Prelaunch at Kennedy Space Center

    On Mars Exploration Rover 1 (MER-1) , air bags are installed on the lander. The airbags will inflate to cushion the landing of the spacecraft on the surface of Mars. When it stops bouncing and rolling, the airbags will deflate and retract, the petals will open to bring the lander to an upright position, and the rover will be exposed. NASA's twin Mars Exploration Rovers are designed to study the history of water on Mars. These robotic geologists are equipped with a robotic arm, a drilling tool, three spectrometers, and four pairs of cameras that allow them to have a human-like, 3D view of the terrain. Each rover could travel as far as 100 meters in one day to act as Mars scientists' eyes and hands, exploring an environment where humans can't yet go. MER-1 is scheduled to launch June 25 as MER-B aboard a Delta II rocket from Cape Canaveral Air Force Station.

  15. Descent vehicles

    NASA Technical Reports Server (NTRS)

    Popov, Y. I.

    1985-01-01

    The creation of descent vehicles marked a new stage in the development of cosmonautics, involving the beginning of manned space flight and substantial progress in space research on the distant bodies of the Solar System. This booklet describes these vehicles and their structures, systems, and purposes. It is intended for the general public interested in modern problems of space technology.

  16. Vehicle systems

    NASA Technical Reports Server (NTRS)

    Bales, Tom; Modlin, Tom; Suddreth, Jack; Wheeler, Tom; Tenney, Darrel R.; Bayless, Ernest O.; Lisagor, W. Barry; Bolstad, Donald A.; Croop, Harold; Dyer, J.

    1993-01-01

    Perspectives of the subpanel on expendable launch vehicle structures and cryotanks are: (1) new materials which provide the primary weight savings effect on vehicle mass/size; (2) today's investment; (3) typically 10-20 years to mature and fully characterize new materials.

  17. Vehicle systems

    Microsoft Academic Search

    Tom Bales; Tom Modlin; Jack Suddreth; Tom Wheeler; Darrel R. Tenney; Ernest O. Bayless; W. Barry Lisagor; Donald A. Bolstad; Harold Croop; J. Dyer

    1993-01-01

    Perspectives of the subpanel on expendable launch vehicle structures and cryotanks are: (1) new materials which provide the primary weight savings effect on vehicle mass\\/size; (2) today's investment; (3) typically 10-20 years to mature and fully characterize new materials.

  18. Air bag restraint device

    DOEpatents

    Marts, Donna J. (Idaho Falls, ID); Richardson, John G. (Idaho Falls, ID)

    1995-01-01

    A rear-seat air bag restraint device is disclosed that prevents an individual, or individuals, from continuing violent actions while being transported in a patrol vehicle's rear seat without requiring immediate physical contact by the law enforcement officer. The air bag is activated by a control switch in the front seat and inflates to independently restrict the amount of physical activity occurring in the rear seat of the vehicle while allowing the officer to safely stop the vehicle. The air bag can also provide the officer additional time to get backup personnel to aid him if the situation warrants it. The bag is inflated and maintains a constant pressure by an air pump.

  19. R-134a emissions from vehicles.

    PubMed

    Siegl, W O; Wallington, T J; Guenther, M T; Henney, T; Pawlak, D; Duffy, M

    2002-02-15

    We report the first study of R-134a (also known as HFC-134a and CF3CFH2) refrigerant leakage from air conditioning (AC) systems of modern vehicles. Twenty-eight light duty vehicles from five manufacturers (Ford, Toyota, Daimler Chrysler, General Motors, and Honda) were tested according to the USEPA (Federal) extended diurnal test procedure using the Sealed Housing for Evaporative Determination (SHED) apparatus. All tests were conducted using stationary vehicles with the motor and air conditioning system turned off. R-134a was measured using gas chromatography (GC) with a flame ionization detector (FID). All vehicles exhibited measurable R-134a leakage over the 2-day diurnal test. Leak rates of R-134a ranged from 0.01 to 0.36 g/day with an average of 0.07+/-0.07 g/day. When combined with leakage associated with vehicle operation, servicing, and disposal we estimate that the lifetime average R-134a emission rate from an AC equipped vehicle is 0.41+/-0.27 g/day (the majority of emissions are associated with vehicle servicing and disposal). Assuming that the average vehicle travels 10 000 miles per year we estimate that the global warming impact of R-134a leakage from an AC equipped vehicle is approximately 4-5% of that of the CO2 emitted by the vehicle. The results are discussed with respect to the contribution of vehicle emissions to global climate change. PMID:11878368

  20. Control architectures for autonomous underwater vehicles

    Microsoft Academic Search

    Kimon P. Valavanis; Denis Gracanin; Maja Matijasevic; Ramesh Kolluru; Georgios A. Demetriou

    1997-01-01

    Autonomous underwater vehicles (AUVs) share common control problems with other air, land, and water unmanned vehicles. In addition to requiring high-dimensional and computationally intensive sensory data for real-time mission execution, power and communication limitations in an underwater environment make it more difficult to develop a control architecture for an AUV. In this article, the four types of control architectures being

  1. Cooperative control of autonomous underwater vehicles

    E-print Network

    Savage, Elizabeth

    2004-09-30

    The proposed project is the simulation of a system to search for air vehicles which have splashed-down in the ocean. The system comprises a group of 10+ autonomous underwater vehicles, which cooperate in order to locate the aircraft. The search...

  2. Fuel cell and battery electric vehicles compared

    Microsoft Academic Search

    C. E. Thomas

    2009-01-01

    Several alternative vehicle and fuel options are under consideration to alleviate the triple threats of climate change, urban air pollution and foreign oil dependence caused by motor vehicles. This paper evaluates the primary transportation alternatives and determines which hold the greatest potential for averting societal threats. We developed a dynamic computer simulation model that compares the societal benefits of replacing

  3. 29 CFR 1926.306 - Air receivers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...intended to apply to compressed air machinery and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and automotive equipment. (2) New and existing equipment. (i) All new air receivers...

  4. 29 CFR 1910.169 - Air receivers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...intended to apply to compressed air machinery and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and automotive equipment. (2) New and existing equipment. (i) All new air receivers...

  5. 29 CFR 1926.306 - Air receivers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...intended to apply to compressed air machinery and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and automotive equipment. (2) New and existing equipment. (i) All new air receivers...

  6. 29 CFR 1910.169 - Air receivers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...intended to apply to compressed air machinery and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and automotive equipment. (2) New and existing equipment. (i) All new air receivers...

  7. 29 CFR 1926.306 - Air receivers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...intended to apply to compressed air machinery and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and automotive equipment. (2) New and existing equipment. (i) All new air receivers...

  8. 29 CFR 1910.169 - Air receivers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...intended to apply to compressed air machinery and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and automotive equipment. (2) New and existing equipment. (i) All new air receivers...

  9. Robotic vehicle

    DOEpatents

    Box, W.D.

    1997-02-11

    A robotic vehicle is described for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendable appendages, each of which is radially extendable relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendable members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle. 20 figs.

  10. Robotic vehicle

    DOEpatents

    Box, W.D.

    1998-08-11

    A robotic vehicle is described for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendible appendages, each of which is radially extendible relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendible members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle. 20 figs.

  11. Robotic vehicle

    DOEpatents

    Box, W. Donald (Oak Ridge, TN)

    1997-01-01

    A robotic vehicle for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendable appendages, each of which is radially extendable relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendable members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle.

  12. Robotic vehicle

    DOEpatents

    Box, W. Donald (Oak Ridge, TN)

    1998-01-01

    A robotic vehicle for travel through a conduit. The robotic vehicle includes forward and rear housings each having a hub portion, and each being provided with surface engaging mechanisms for selectively engaging the walls of the conduit such that the housings can be selectively held in stationary positions within the conduit. The surface engaging mechanisms of each housing includes a plurality of extendable appendages, each of which is radially extendable relative to the operatively associated hub portion between a retracted position and a radially extended position. The robotic vehicle also includes at least three selectively extendable members extending between the forward and rear housings, for selectively changing the distance between the forward and rear housings to effect movement of the robotic vehicle.

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

    NASA Technical Reports Server (NTRS)

    Kim, Hyun D.; Frate, Franco C.

    2001-01-01

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

  14. The Characterization of Material Properties and Structural Dynamics of the Manduca Sexta Forewing for Application to Flapping Wing Micro Air Vehicle Design

    NASA Astrophysics Data System (ADS)

    O'Hara, Ryan P.

    Collateral damage presents a significant risk during air drops and airstrikes, risking citizens' lives and property, straining the relationship between the United States Air Force and host nations. This dissertation presents a methodology to determine the optimal location for making supply airdrops in order to minimize collateral damage while maintaining a high likelihood of successful recovery. A series of non-linear optimization algorithms are presented along with their relative success in finding the optimal location in the airdrop problem. Additionally, we present a quick algorithm for accurately creating the Pareto frontier in the multi-objective airstrike problem. We demonstrate the effect of differing guidelines, damage functions, and weapon employment selection which significantly alter the location of the optimal aimpoint in this targeting problem. Finally, we have provided a framework for making policy decisions in fast-moving troops-in-contact situations where observers are unsure of the nature of possible enemy forces in both finite and infinite time horizon problems. Through a recursive technique of solving this Markov decision process we have demonstrated the effect of improved intelligence and differing weights in the face of uncertain situations.

  15. 40 CFR 86.1822-01 - Durability data vehicle selection.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...AND IN-USE HIGHWAY VEHICLES AND ENGINES General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1822-01...

  16. Guidance Based Collision Avoidance of Coordinated Nonholonomic Autonomous Vehicles

    E-print Network

    Paris-Sud XI, Université de

    Guidance Based Collision Avoidance of Coordinated Nonholonomic Autonomous Vehicles Xianbo Xiang, as coordinated and cooperative autonomous vehicles can be operated at sea, on land, in the air, in space control; in [3], this method is proposed for two underwater autonomous vehicles (AUVs) following two

  17. COOPERATIVE PATH-PLANNING FOR AUTONOMOUS VEHICLES USING DYNAMIC

    E-print Network

    Fernandez, Emmanuel

    COOPERATIVE PATH-PLANNING FOR AUTONOMOUS VEHICLES USING DYNAMIC PROGRAMMING 1 Matthew Flint, Marios@ececs.uc.edu Abstract: It is shown how to model a cooperative path planning system for multiple autonomous air vehicles of uncertainty and constraints on movement and computational power. Keywords: Agent, Autonomous Vehicle, Co

  18. Earth-Mars similarity criteria for exploring martian vehicles

    Microsoft Academic Search

    G. Savu

    2003-01-01

    In order to select the most efficient kind of a martian exploring vehicle, the similarity criteria are deduced from the equilibrium movement in the terrestrial and martian conditions. Different invariants have been obtained for the existing (entry capsules, parachutes and rovers) and potential martian exploring vehicles (lighter-than-air vehicle, airplane, helicopter and Mars Jumper). These similarity criteria, as non dimensional numbers,

  19. Taking a new look at hybrid electric vehicle efficiency

    SciTech Connect

    NONE

    1997-02-01

    Environmental, economic, and national security challenges from passenger-car use have energized development of hybrid electric vehicles (HEV) worldwide. These vehicles could reduce fuel consumption, use nonpetroleum alternative fuels, and reduce urban air pollution and greenhouse gas emissions. Current thinking on hybrid electric vehicles may be underestimating their significance to reducing petroleum use.

  20. Sparse representation for vehicle recognition

    NASA Astrophysics Data System (ADS)

    Monnig, Nathan D.; Sakla, Wesam

    2014-06-01

    The Sparse Representation for Classification (SRC) algorithm has been demonstrated to be a state-of-the-art algorithm for facial recognition applications. Wright et al. demonstrate that under certain conditions, the SRC algorithm classification performance is agnostic to choice of linear feature space and highly resilient to image corruption. In this work, we examined the SRC algorithm performance on the vehicle recognition application, using images from the semi-synthetic vehicle database generated by the Air Force Research Laboratory. To represent modern operating conditions, vehicle images were corrupted with noise, blurring, and occlusion, with representation of varying pose and lighting conditions. Experiments suggest that linear feature space selection is important, particularly in the cases involving corrupted images. Overall, the SRC algorithm consistently outperforms a standard k nearest neighbor classifier on the vehicle recognition task.

  1. Life history of the long-lived gynodioecious cushion plant Silene acaulis (Caryophyllaceae), inferred from size-based population projection matrices.

    PubMed

    Morris, W; Doak, D

    1998-06-01

    Alpine plants often appear to have long life-spans as an adaptation to harsh and unpredictable environmental conditions, yet many lack reliable indicators of age that would make it possible to determine their true longevity. Their extended life-spans also pose problems for measuring lifetime reproductive success, a key component of breeding system evolution in species such as the gynodioecious cushion plant Silene acaulis. For a population of S. acaulis in south-central Alaska, we applied a recently derived analytical approach using size-based population projection matrices that allowed us to estimate: (1) the relationship between cushion diameter and age; and (2) lifetime reproductive success through seed production by females relative to hermaphrodites. Because of a combination of slow growth, frequent shrinkage, and extremely high adult survival, we estimate that the largest cushions in our study population exceed 300 yr in age, and some may live substantially longer, despite the seemingly inhospitable alpine environment they inhabit. Females are estimated to produce 4.4 times as many offspring via seed production over the course of their lives as do hermaphrodites, a difference that is more than sufficient to assure the persistence of females despite their inability to transmit genes through pollen. These results highlight the utility of size-based projection matrices for studying the life histories of herbaceous perennials whose life-span and lifetime reproductive success cannot be determined easily by any other means. PMID:21684962

  2. Air pollution

    SciTech Connect

    Not Available

    1991-06-01

    Gasoline vapors from motor vehicles contributed to smog and can aggravate respiratory problems of millions of Americans. In 1987 the Environmental Protection Agency proposed a regulation requiring that motor vehicles be equipped with onboard systems to control about 90 percent of refueling vapors. The Department of Transportation's National Highway Traffic Safety Administration, however, raised concerns about the safety of these systems, thereby locking approval of the regulation. EPA and the National Highway Traffic Safety Administration have not yet resolved their four-year impasses over whether onboard vapor recovery systems will increase the likelihood of vehicle crash fires and fuel spillage. As a result, no agreement has been reached on the data and analysis needed to address the safety risk of onboard systems. GAO recommends that EPA go forward with the onboard regulation by November 1991 as required by the Clean Air act Amendments of 1990 unless EPA determines that onboard systems pose an unreasonable risk to public safety. This paper reports that to identify and correct any safety defects or flaws well in advance of the 1996 model year so that an orderly phase-in occurs, GAO also recommends that EPA and the National Highway Traffic Safety Administration develop a joint approach to safety evaluations of manufacturer's onboard systems.

  3. 40 CFR 1066.845 - AC17 air conditioning efficiency test procedure.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...false AC17 air conditioning efficiency test procedure. 1066.845 Section 1066...VEHICLE-TESTING PROCEDURES Exhaust Emission Test Procedures for Motor Vehicles § 1066.845 AC17 air conditioning efficiency test procedure. (a) Overview....

  4. Vehicle structure

    SciTech Connect

    Stroud, E.A.

    1984-05-01

    There is provided a vehicle which includes a frame, a steerable wheel mounted on the frame and at least one further wheel mounted for free rotation on the frame. A flywheel is mounted for rotation adjacent one of the wheels. The vehicle includes means for imparting rotation to the flywheel, and a clutch plate rotatably and coaxially mounted adjacent the same wheel to which the flywheel is adjacent. Speed-reduction means allows rotation of the flywheel to rotate the clutch plate at a faster rate than the flywheel, and a frictionless clutch is provided between the clutch plate and the adjacent wheel.

  5. A MODULAR, SCALABLE, ARCHITECTURE FOR UNMANNED VEHICLES

    Microsoft Academic Search

    David G. Armstrong II; Carl D. Crane; David Novick; Jeffrey Wit; Ralph English; Phillip Adsit; David Shahady

    2000-01-01

    A modular, scalable architecture for use on unmanned vehicles has been developed at the Center for Intelligent Machines and Robotics under the direction of the Air Force Research Laboratory at Tyndall Air Force Base, FL. This state of the art architecture isolates five functionally cohesive sub-tasks into self-contained modules with well defined interfaces. The architecture consists of a Mob ility

  6. REFRIGERANT CONCENTRATIONS IN MOTOR VEHICLE PASSENGER COMPARTMENTS

    EPA Science Inventory

    Refrigerant leak rates were measured for faulty air-conditioner evaporators removed from vehicles, and results indicated a range of very small to very large leaks. A survey of automotive air-conditioning service shops was conducted, and leakage scenarios were evaluated to determi...

  7. Chemical Degradation of Siloxane Stress Cushions (M97 and S5370) by Thermal, Mechanical and Spectroscopic Investigations

    SciTech Connect

    Maxwell, R S; Gee, R; Balazs, B; Cohenour, R; Sung, B

    2002-04-19

    We are currently investigating the long term aging of weapon organics in an effort to develop predictive capabilities for functional service life. As part of this effort, we have been studying multimechanism aging of M97 and 53370 stress cushions. Ionizing radiation, thermal degradation, and desiccation all affect the crosslink density and motional dynamics and thus the engineering performance of these materials. Our approach has been to develop molecular level understanding of the effects of such aging mechanisms on polymer properties by a combined approach utilizing solvent swelling, thermal, DMA, molecular modeling, and solid state NMR. This presentation will offer a survey of our current work, concentrating on the application of solid state NMR for correlating structure and polymer dynamics. An overview of the relationships between crosslink density, NMR relaxation times, polymer chain dynamics, and storage modulus measurements will be presented and the advantages of NMR will be discussed. It will be shown that silicone based polymers tend to crosslink upon exposure to {gamma}-radiation, undergo chain scission upon thermal degradation, and stiffen upon desiccation.

  8. Sick leave -- Cushion or entitlement? A study of age cohorts' attitudes and practices in two Australian workplaces.

    PubMed

    Cant, Rosemary; O'Loughlin, Kate; Legge, Varoe

    2001-01-01

    Stereotypes of older people suggest that they may experience more sickness and injury therefore may not be as productive as younger employees. The present paper attempts to test these stereotypes and reports research into patterns of sick leave in different age cohorts and attitudes towards the use of sick leave. The research was carried out at two case study sites. Managers were interviewed and focus groups were held with workers. A complex pattern was found, suggesting structural issues such as sick leave entitlements, workplace organisation, and flexible work patterns interacted with managers' and workers' attitudes, age, gender and family responsibilities. Flexible workplace hours, and part payment for unused sick leave and insecurity of employment appeared as important factors in reducing absenteeism. The most striking finding was that older workers past pensionable age took the least sick leave. Older workers were careful to conserve sick leave as a 'cushion' for serious illness. Workplace pressures especially those resulting from the failure of management to replace absent workers resulted in work pressure on peers and thus reluctance of workers to take leave. PMID:12441621

  9. Zhang, K., and H.C. Frey, "Road Grade Estimation for On-Road Vehicle Emissions Modeling Using LIDAR Data," Proceedings, Annual Meeting of the Air & Waste Management Association, June 20-23, 2005, Minneapolis, MN

    E-print Network

    Frey, H. Christopher

    Zhang, K., and H.C. Frey, "Road Grade Estimation for On-Road Vehicle Emissions Modeling Using LIDAR, Minneapolis, MN - 1 - ROAD GRADE ESTIMATION FOR ON-ROAD VEHICLE EMISSIONS MODELING USING LIDAR DATA 05-A-1137 emissions monitoring systems (PEMS). VSP is calculated based upon vehicle speed, acceleration, and road

  10. An Approach to using Honeypots in In-Vehicle Networks

    Microsoft Academic Search

    Vilhelm Verendel; Dennis K. Nilsson; Ulf E. Larson; Erland Jonsson

    2008-01-01

    An emerging trend among automobile manufacturers is to introduce wireless technology in the vehicles. By allowing wireless communication, real-time information exchange between vehicles as well as between infrastructure and vehicles becomes a reality. This communication allows for road condition reporting, decision making, and remote diagnostics and firmware updates over-the-air, creating a complex critical infrastructure involving vehicles, road-side equipment, and firmware

  11. Robotic vehicle

    DOEpatents

    Box, W.D.

    1994-03-15

    A robotic vehicle is described for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle comprises forward and rear housings each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings are selectively held in a stationary position within the conduit. The vehicle also includes at least three selectively extendable members, each of which defines a cavity therein. The forward end portion of each extendable member is secured to the forward housing and the rear end portion of each housing is secured to the rear housing. Each of the extendable members is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively increased. Further, each of the extendable members is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively decreased. 11 figures.

  12. Robotic vehicle

    DOEpatents

    Box, W.D.

    1996-03-12

    A robotic vehicle is described for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle comprises forward and rear housings each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings are selectively held in a stationary position within the conduit. The vehicle also includes at least three selectively extendable members, each of which defines a cavity therein. The forward end portion of each extendable member is secured to the forward housing and the rear end portion of each housing is secured to the rear housing. Each of the extendable members is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively increased. Further, each of the extendable members is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity of the extendable member such that the distance between the forward housing and the rear housing can be selectively decreased. 14 figs.

  13. Robotic vehicle

    DOEpatents

    Box, W. Donald (115 Newhaven Rd., Oak Ridge, TN 37830)

    1994-01-01

    A robotic vehicle (10) for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle (10) comprises forward and rear housings (32 and 12) each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings (32 and 12) are selectively held in a stationary position within the conduit. The vehicle (10) also includes at least three selectively extendable members (46), each of which defines a cavity (56) therein. The forward end portion (50) of each extendable member (46) is secured to the forward housing (32) and the rear end portion (48) of each housing is secured to the rear housing (12). Each of the extendable members (46) is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity (56) of the extendable member such that the distance between the forward housing (32 ) and the rear housing (12) can be selectively increased. Further, each of the extendable members (46) is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity (56) of the extendable member (46) such that the distance between the forward housing (32) and the rear housing (12) can be selectively decreased.

  14. Robotic vehicle

    DOEpatents

    Box, W. Donald (Oak Ridge, TN)

    1996-01-01

    A robotic vehicle (10) for travel through an enclosed or partially enclosed conduit or pipe including vertical and/or horizontal conduit or pipe. The robotic vehicle (10) comprises forward and rear housings (32 and 12) each provided with a surface engaging mechanism for selectively engaging the walls of the conduit through which the vehicle is travelling, whereby the housings (32 and 12) are selectively held in a stationary position within the conduit. The vehicle (10) also includes at least three selectively extendable members (46), each of which defines a cavity (56) therein. The forward end portion (50) of each extendable member (46) is secured to the forward housing (32) and the rear end portion (48) of each housing is secured to the rear housing (12). Each of the extendable members (46) is independently extendable from a retracted position to an extended position upon the injection of a gas under pressure into the cavity (56) of the extendable member such that the distance between the forward housing (32 ) and the rear housing (12) can be selectively increased. Further, each of the extendable members (46) is independently retractable from the extended position to the retracted position upon the application of a vacuum to the cavity (56) of the extendable member (46) such that the distance between the forward housing (32) and the rear housing (12) can be selectively decreased.

  15. Predictors of Hazardous Child Seating Behavior in Fatal Motor Vehicle Crashes: 1990 to 1998

    Microsoft Academic Search

    Eve Wittenberg; Sue J. Goldie; John D. Graham

    2010-01-01

    Objective. Motor vehicle crashes are the leading cause of death in children ages 5 to 14. Children seated in the front seats of vehicles are at increased risk of death and injury in crashes, particularly in vehicles with passenger-side air bags. This study identifies fac- tors associated with the seating of children in the front seats of vehicles involved in

  16. Vehicle Systems Panel deliberations

    Microsoft Academic Search

    Tom Bales; Tom Modlin; Jack Suddreth; Tom Wheeler; Darrel R. Tenney; Ernest O. Bayless; W. Barry Lisagor; Donald A. Bolstad; Harold Croop; J. Dyer

    1993-01-01

    The Vehicle Systems Panel addressed materials and structures technology issues related to launch and space vehicle systems not directly associated with the propulsion or entry systems. The Vehicle Systems Panel was comprised of two subpanels - Expendable Launch Vehicles & Cryotanks (ELVC) and Reusable Vehicles (RV). Tom Bales, LaRC, and Tom Modlin, JSC, chaired the expendable and reusable vehicles subpanels,

  17. PITX2 Loss-of-Function Mutation Contributes to Congenital Endocardial Cushion Defect and Axenfeld-Rieger Syndrome

    PubMed Central

    Zhao, Cui-Mei; Peng, Lu-Ying; Li, Li; Liu, Xing-Yuan; Wang, Juan; Zhang, Xian-Ling; Yuan, Fang; Li, Ruo-Gu; Qiu, Xing-Biao; Yang, Yi-Qing

    2015-01-01

    Congenital heart disease (CHD), the most common type of birth defect, is still the leading non-infectious cause of infant morbidity and mortality in humans. Aggregating evidence demonstrates that genetic defects are involved in the pathogenesis of CHD. However, CHD is genetically heterogeneous and the genetic components underpinning CHD in an overwhelming majority of patients remain unclear. In the present study, the coding exons and flanking introns of the PITX2 gene, which encodes a paired-like homeodomain transcription factor 2essential for cardiovascular morphogenesis as well as maxillary facial development, was sequenced in 196 unrelated patients with CHD and subsequently in the mutation carrier’s family members available. As a result, a novel heterozygous PITX2 mutation, p.Q102X for PITX2a, or p.Q148X for PITX2b, or p.Q155X for PITX2c, was identified in a family with endocardial cushion defect (ECD) and Axenfeld-Rieger syndrome (ARS). Genetic analysis of the pedigree showed that the nonsense mutation co-segregated with ECD and ARS transmitted in an autosomal dominant pattern with complete penetrance. The mutation was absent in 800 control chromosomes from an ethnically matched population. Functional analysis by using a dual-luciferase reporter assay system revealed that the mutant PITX2 had no transcriptional activity and that the mutation eliminated synergistic transcriptional activation between PITX2 and NKX2.5, another transcription factor pivotal for cardiogenesis. To our knowledge, this is the first report on the association of PITX2 loss-of-function mutation with increased susceptibility to ECD and ARS. The findings provide novel insight into the molecular mechanisms underpinning ECD and ARS, suggesting the potential implications for the antenatal prophylaxis and personalized treatment of CHD and ARS. PMID:25893250

  18. GENERAL VIEW OF NORTH VEHICLE ACCESS PLATFORMS, HB3, FACING NORTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF NORTH VEHICLE ACCESS PLATFORMS, HB-3, FACING NORTH TOWARDS FLOOR - Cape Canaveral Air Force Station, Launch Complex 39, Vehicle Assembly Building, VAB Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  19. GENERAL VIEW OF VEHICLE ACCESS PLATFORM ENORTH, HB3, FACING NORTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF VEHICLE ACCESS PLATFORM E-NORTH, HB-3, FACING NORTH - Cape Canaveral Air Force Station, Launch Complex 39, Vehicle Assembly Building, VAB Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  20. GENERAL VIEW OF VEHICLE ACCESS PLATFORM ENORTH, HB3, FACING NORTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF VEHICLE ACCESS PLATFORM E-NORTH, HB-3, FACING NORTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Vehicle Assembly Building, VAB Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  1. GENERAL VIEW OF VEHICLE ACCESS PLATFORM BNORTH, HB3, FACING NORTHEAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF VEHICLE ACCESS PLATFORM B-NORTH, HB-3, FACING NORTHEAST - Cape Canaveral Air Force Station, Launch Complex 39, Vehicle Assembly Building, VAB Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  2. GENERAL VIEW OF VEHICLE ACCESS PLATFORM BNORTH, HB3, FACING NORTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF VEHICLE ACCESS PLATFORM B-NORTH, HB-3, FACING NORTH - Cape Canaveral Air Force Station, Launch Complex 39, Vehicle Assembly Building, VAB Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  3. GENERAL VIEW OF VEHICLE ACCESS PLATFORM DNORTH, HB3, FACING NORTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF VEHICLE ACCESS PLATFORM D-NORTH, HB-3, FACING NORTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Vehicle Assembly Building, VAB Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  4. GENERAL VIEW OF NORTH VEHICLE ACCESS PLATFORMS, HB3, FACING NORTHEAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF NORTH VEHICLE ACCESS PLATFORMS, HB-3, FACING NORTHEAST TOWARDS CEILING - Cape Canaveral Air Force Station, Launch Complex 39, Vehicle Assembly Building, VAB Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  5. GENERAL VIEW OF VEHICLE ACCESS PLATFORM DNORTH, HB3, FACING NORTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF VEHICLE ACCESS PLATFORM D-NORTH, HB-3, FACING NORTH - Cape Canaveral Air Force Station, Launch Complex 39, Vehicle Assembly Building, VAB Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  6. Design and characterization of Hover Nano Aerial Vehicle (HNAV) propulsion system

    E-print Network

    Sato, Sho, Ph. D. Massachusetts Institute of Technology

    2008-01-01

    On October 4th 2005, DARPA released a request for proposals for a Nano-Air Vehicle (NAV) program. The program sought to develop an advanced urban reconnaissance vehicle. According the requirement imposed by DARPA, the NAV ...

  7. A high-resolution vehicle emission inventory for China

    NASA Astrophysics Data System (ADS)

    Zheng, B.; Zhang, Q.; He, K.; Huo, H.; Yao, Z.; Wang, X.

    2012-12-01

    Developing high resolution emission inventory is an essential task for air quality modeling and management. However, current vehicle emission inventories in China are usually developed at provincial level and then allocated to grids based on various spatial surrogates, which is difficult to get high spatial resolution. In this work, we developed a new approach to construct a high-resolution vehicle emission inventory for China. First, vehicle population at county level were estimated by using the relationship between per-capita GDP and vehicle ownership. Then the Weather Research and Forecasting (WRF) model were used to drive the International Vehicle Emission (IVE) model to get monthly emission factors for each county. Finally, vehicle emissions by county were allocated to grids with 5-km horizon resolution by using high-resolution road network data. This work provides a better understanding of spatial representation of vehicle emissions in China and can benefit both air quality modeling and management with improved spatial accuracy.

  8. Vehicle barrier

    DOEpatents

    Hirsh, Robert A. (Bethel Park, PA)

    1991-01-01

    A vehicle security barrier which can be conveniently placed across a gate opening as well as readily removed from the gate opening to allow for easy passage. The security barrier includes a barrier gate in the form of a cable/gate member in combination with laterally attached pipe sections fixed by way of the cable to the gate member and lateral, security fixed vertical pipe posts. The security barrier of the present invention provides for the use of cable restraints across gate openings to provide necessary security while at the same time allowing for quick opening and closing of the gate areas without compromising security.

  9. REGISTRANT INFORMATION VEHICLE INFORMATION

    E-print Network

    Wlodawer, Alexander

    REGISTRANT INFORMATION VEHICLE INFORMATION Vehicle Make: Vehicle Model:: Vehicle Year:Body Style: Vehicle Color: VIN # : LICENSE INFORMATION Tag # : Expiration Date :State : INSURANCE INFORMATION Policy OrganizationCategoryGrade / Rank StateDOB Sex Race Height Weight Eye Color Hair Color Driver's License

  10. Unmanned Vehicle Situation Awareness

    Microsoft Academic Search

    Julie A. Adams

    This paper presents the concept of unmanned vehicle situation awareness and provides a discussion of how unmanned vehicle situation awareness can be defined based upon human situation awareness. A broadly accepted human situation awareness definition is directly applied to the notion of unmanned vehicle situation awareness. The paper also discusses unique unmanned vehicle aspects that will influence unmanned vehicle situation

  11. X-34 Vehicle Aerodynamic Characteristics

    NASA Technical Reports Server (NTRS)

    Brauckmann, Gregory J.

    1998-01-01

    The X-34, being designed and built by the Orbital Sciences Corporation, is an unmanned sub-orbital vehicle designed to be used as a flying test bed to demonstrate key vehicle and operational technologies applicable to future reusable launch vehicles. The X-34 will be air-launched from an L-1011 carrier aircraft at approximately Mach 0.7 and 38,000 feet altitude, where an onboard engine will accelerate the vehicle to speeds above Mach 7 and altitudes to 250,000 feet. An unpowered entry will follow, including an autonomous landing. The X-34 will demonstrate the ability to fly through inclement weather, land horizontally at a designated site, and have a rapid turn-around capability. A series of wind tunnel tests on scaled models was conducted in four facilities at the NASA Langley Research Center to determine the aerodynamic characteristics of the X-34. Analysis of these test results revealed that longitudinal trim could be achieved throughout the design trajectory. The maximum elevon deflection required to trim was only half of that available, leaving a margin for gust alleviation and aerodynamic coefficient uncertainty. Directional control can be achieved aerodynamically except at combined high Mach numbers and high angles of attack, where reaction control jets must be used. The X-34 landing speed, between 184 and 206 knots, is within the capabilities of the gear and tires, and the vehicle has sufficient rudder authority to control the required 30-knot crosswind.

  12. Explosives screening on a vehicle surface

    DOEpatents

    Parmeter, John E.; Brusseau, Charles A.; Davis, Jerry D.; Linker, Kevin L.; Hannum, David W.

    2005-02-01

    A system for detecting particles on the outer surface of a vehicle has a housing capable of being placed in a test position adjacent to, but not in contact with, a portion of the outer surface of the vehicle. An elongate sealing member is fastened to the housing along a perimeter surrounding the wall, and the elongate sealing member has a contact surface facing away from the wall to contact the outer surface of the vehicle to define a test volume when the wall is in the test position. A gas flow system has at least one gas inlet extending through the wall for providing a gas stream against the surface of the vehicle within the test volume. This gas stream, which preferably is air, dislodges particles from the surface of the vehicle covered by the housing. The gas stream exits the test volume through a gas outlet and particles in the stream are detected.

  13. Simulating vehicle dynamics: The importance of a valid forcing function

    SciTech Connect

    Ferguson, G.L.

    1988-01-01

    The recent evolution of vehicle systems has required they be structurally sound with minimum weight. Historically, a trial and error approach to marketing a vehicle was used. The 1970s saw mainframe computers speed the vehicle design process. In the early 1980s simulating vehicle dynamics became the accepted design procedure. The forcing function used in this technique is also its major drawback. This paper summarizes the results of one sled vehicle used in a detailed study done at the U. S. Air Force's High Speed Test Track. The study concluded that results from simulation studies are valid only if an accurate forcing function is used. 6 refs., 14 figs.

  14. California Greenhouse Gas Emissions Standards for Light-Duty Vehicles (Update) (released in AEO2006)

    EIA Publications

    2006-01-01

    The state of California was given authority under the Clean Air Act Amendments of 1990 (CAAA90) to set emissions standards for light-duty vehicles that exceed federal standards. In addition, other states that do not comply with the National Ambient Air Quality Standards (NAAQS) set by the Environmental Protection Agency under CAAA90 were given the option to adopt Californias light-duty vehicle emissions standards in order to achieve air quality compliance. CAAA90 specifically identifies hydrocarbon, carbon monoxide, and NOx as vehicle-related air pollutants that can be regulated. California has led the nation in developing stricter vehicle emissions standards, and other states have adopted the California standards.

  15. Circulatory system for unmanned air vehicles

    NASA Astrophysics Data System (ADS)

    Nagar, Anoop; Anderson, Eric; Rao, Preethi; Narang, Subhash

    2007-04-01

    We have built a platform circulatory system by fabricating channels whose dimensions and layout are analogous to a fractal system where the reactants (fluids) are carried from a central reservoir, through progressively smaller channels ultimately with a width of 100 microns as they interface with the cellular structure. The construction of the macro/micro channel platform has been carried out using the direct write/solid freeform photo fabrication hybrid platform developed by the principle investigator. The interaction of reactants is controlled at the cellular level depending upon the fractional change in structural properties to be performed. The macro/micro channel system is metallized with copper, nickel and gold to enable to allow electrochemical transformations on demand. The circulatory system has been used to increase the modulus of a beam by polymerizing monomers to high modulus polymers with a view towards repairing structural damage. The metallized channels have been used to alter the electromagnetic absorption of a structure via electrochemical switching between conducting, semiconducting and insulating states. The electromagnetic characteristics have also been altered by replacing the dopant anions with anions of significantly altered stereoelectronic characteristics by taking advantage of the circulatory system.

  16. Integrated Collision Avoidance System for Air Vehicle

    NASA Technical Reports Server (NTRS)

    Lin, Ching-Fang (Inventor)

    2013-01-01

    Collision with ground/water/terrain and midair obstacles is one of the common causes of severe aircraft accidents. The various data from the coremicro AHRS/INS/GPS Integration Unit, terrain data base, and object detection sensors are processed to produce collision warning audio/visual messages and collision detection and avoidance of terrain and obstacles through generation of guidance commands in a closed-loop system. The vision sensors provide more information for the Integrated System, such as, terrain recognition and ranging of terrain and obstacles, which plays an important role to the improvement of the Integrated Collision Avoidance System.

  17. Modal analysis of PATHFINDER unmanned air vehicle

    Microsoft Academic Search

    T. G. Woehrle; B. W. Costerus; C. L. Lee

    1994-01-01

    An experimental modal analysis was performed on PATHFINDER, a 450-lb, 100-ft wing span, flying-wing-design aircraft powered by solar\\/electric motors. The aircraft was softly suspended and then excited using random input from a long-stroke shaker. Modal data was taken from 92 measurement locations on the aircraft using newly designed, lightweight, tri-axial accelerometers. A conventional PC-based data acquisition system provided data handling.

  18. Simulated global change: contrasting short and medium term growth and reproductive responses of a common alpine/Arctic cushion plant to experimental warming and nutrient enhancement.

    PubMed

    Alatalo, Juha M; Little, Chelsea J

    2014-01-01

    Cushion plants are important components of alpine and Arctic plant communities around the world. They fulfill important roles as facilitators, nurse plants and foundation species across trophic levels for vascular plants, arthropods and soil microorganisms, the importance of these functions increasing with the relative severity of the environment. Here we report results from one of the few experimental studies simulating global change impacts on cushion plants; a factorial experiment with warming and nutrient enhancement that was applied to an alpine population of the common nurse plant, Silene acaulis, in sub-arctic Sweden. Experimental perturbations had significant short-term impacts on both stem elongation and leaf length. S. acaulis responded quickly by increasing stem elongation and (to a lesser extent) leaf length in the warming, nutrient, and the combined warming and nutrient enhancements. Cover and biomass also initially increased in response to the perturbations. However, after the initial positive short-term responses, S. acaulis cover declined in the manipulations, with the nutrient and combined warming and nutrient treatments having largest negative impact. No clear patterns were found for fruit production. Our results show that S. acaulis living in harsh environments has potential to react quickly when experiencing years with favorable conditions, and is more responsive to nutrient enhancement than to warming in terms of vegetative growth. While these conditions have an initial positive impact, populations experiencing longer-term increased nutrient levels will likely be negatively affected. PMID:24790813

  19. Dynamics of aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Schmidt, David K.

    1991-01-01

    Papers on the following subjects are presented: (1) multivariable flight control synthesis and literal robustness analysis for an aeroelastic vehicles; (2) numerical and literal aeroelastic-vehicle-model reduction for feedback control synthesis; and (3) dynamics of aerospace vehicles.

  20. Electric-vehicle batteries

    NASA Astrophysics Data System (ADS)

    Oman, Henry; Gross, Sid

    1995-02-01

    Electric vehicles that can't reach trolley wires need batteries. In the early 1900's electric cars disappeared when owners found that replacing the car's worn-out lead-acid battery costs more than a new gasoline-powered car. Most of today's electric cars are still propelled by lead-acid batteries. General Motors in their prototype Impact, for example, used starting-lighting-ignition batteries, which deliver lots of power for demonstrations, but have a life of less than 100 deep discharges. Now promising alternative technology has challenged the world-wide lead miners, refiners, and battery makers into forming a consortium that sponsors research into making better lead-acid batteries. Horizon's new bipolar battery delivered 50 watt-hours per kg (Wh/kg), compared with 20 for ordinary transport-vehicle batteries. The alternatives are delivering from 80 Wh/kg (nickel-metal hydride) up to 200 Wh/kg (zinc-bromine). A Fiat Panda traveled 260 km on a single charge of its zinc-bromine battery. A German 3.5-ton postal truck traveled 300 km with a single charge in its 650-kg (146 Wh/kg) zinc-air battery. Its top speed was 110 km per hour.