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1

Air Cushion Support for Evacuated Tube System Vehicles.  

National Technical Information Service (NTIS)

The practicality of a plenum-type air cushion suspension for evacuated tube system (TVS) vehicles is examined from the standpoint of ideal air cushion/vehicle characteristics (power, mass flow, self-support velocity, cushion temperature), the compressor d...

W. E. Fraize

1971-01-01

2

Tracked Air Cushion Research Vehicle. Vehicle Performance.  

National Technical Information Service (NTIS)

The performance of the TACRV in terms of speed, acceleration and deceleration is discussed in this report and the range of cushion operating gaps is summarized. These performance items are presented for the vehicle operating at the Department of Transport...

C. Savatteri J. Helgesen

1971-01-01

3

Air cushion vehicles - Any potential for Canada?  

NASA Astrophysics Data System (ADS)

The present evaluation of air cushion vehicle (ACV) operational and commercial suitability in the Canadian context notes that the most successful and durable ACV applications are those in which only ACVs can perform the required mission. An important factor is the reliability of the craft being tested in a given field of operations. Because of their low ground pressure, ACVs can operate over low-cost trails with an efficiency that compares with that of trucks over conventional roads; this renders them especially attractive for transportation networks in the North West Territories.

Laframboise, J. F.

1987-09-01

4

Tracked Air Cushion Research Vehicle Perliminary Design Study Report.  

National Technical Information Service (NTIS)

This report presents a preliminary design for a Tracked Air Cusion Research Vehicle (TACRV). The proposed design meets performance, design, and test requirements prescribed by the OHSGT. The research program test requirements emphasize air cushion and sus...

1969-01-01

5

Heave Stability of Air Cushion Vehicles Hovering over Deep Water.  

National Technical Information Service (NTIS)

The heave stability of air cushion vehicles hovering over infinitely deep water is examined theoretically. When applied to the Canadian National Research Council craft, HEX-5, the theory predicts that the volume modulation produced by the spatially averag...

M. J. Hinchey

1982-01-01

6

Feasibility study of helicopter-towed air cushion logistic vehicles  

Microsoft Academic Search

A feasibility study of a helicopter-towed air cushion logistic vehicle (ACLV) was performed. The scope of the study encompassed movement of loaded LASH system lighters on unmanned air-cushion platforms from an off-shore ship onto a sand beach in support of amphibious assault operations. Motive power is to be provided by towing with RH-53 helicopter. Color illustrations reproduced in black and

V. F. Neradka; J. C. Stevens; R. L. Levin

1975-01-01

7

Heave stability of air cushion vehicles hovering over deep water  

Microsoft Academic Search

The heave stability of air cushion vehicles hovering over infinitely deep water is examined theoretically. When applied to the Canadian National Research Council craft, HEX-5, the theory predicts that the volume modulation produced by the spatially averaged deflection of the plenum water free surface would increase the stable operating region relative to overland operation. The air flow modulation produced by

M. J. Hinchey

1982-01-01

8

Operational noise data for the LACV-30 air cushion vehicle  

Microsoft Academic Search

Operational data for the LACV-30 air cushion vehicle were gathered and developed into sound exposure level vs distance curves. These data are available for the Army Environmental Hygiene Agency (AEHA) to use in developing noise zone maps for LACV-30 operations in support of the Army Installation Compatible Use Program (ICUZ). ICUZ defines Hand use compatible with various noise levels and

P. D. Schomer

1985-01-01

9

Heave stability of air cushion vehicles hovering over deep water  

NASA Astrophysics Data System (ADS)

The heave stability of air cushion vehicles hovering over infinitely deep water is examined theoretically. When applied to the Canadian National Research Council craft, HEX-5, the theory predicts that the volume modulation produced by the spatially averaged deflection of the plenum water free surface would increase the stable operating region relative to overland operation. The air flow modulation produced by deflection of the water free surface at the lip of the plenum on the other hand would cause unstable behavior at low cushion pressures.

Hinchey, M. J.

1982-08-01

10

Operational noise data for the LACV-30 air cushion vehicle  

NASA Astrophysics Data System (ADS)

Operational data for the LACV-30 air cushion vehicle were gathered and developed into sound exposure level vs distance curves. These data are available for the Army Environmental Hygiene Agency (AEHA) to use in developing noise zone maps for LACV-30 operations in support of the Army Installation Compatible Use Program (ICUZ). ICUZ defines Hand use compatible with various noise levels and establishes a policy for achieving such uses. Although the Army classifies the LACV-30 as an amphibious vehicle, an examination of its noise characteristics and operations showed it most closely resembles a helicopter. Thus, the methodology for gathering rotary wing aircraft data was used. Measurements of LACV-30's passby runs over water at various distances and speeds were similar in concept to flyover and flyby measurements for helicopters, and the land maneuver measurements corresponded most nearly to a helicopter's hover measurements.

Schomer, P. D.

1985-03-01

11

A Simulation Experiment to Verify Differential Thrust Controller Designs for an Air Cushion Vehicle.  

National Technical Information Service (NTIS)

A manned simulation of an air cushion landing system vehicle was conducted to test the validity of differential thrust controllers that varied with the vehicle's engine time delay. The task was maintaining a constant heading angle in the presence of rando...

A. C. Troy

1976-01-01

12

Test and Demonstration Prototype Tracked Air Cushion Vehicle (PTACV) - Phase IIIC.  

National Technical Information Service (NTIS)

A six year multi-phased program for design, development and test of a prototype tracked air cushion vehicle was culminated in a six month test and demonstration under Phase IIIC. Descriptions of the various major sub-systems are presented with design and ...

A. K. Smith J. Dallas L. Samusson R. Dynes R. Stott

1977-01-01

13

An Analysis of Skill Requirements for Operators of Amphibious Air Cushion Vehicles (ACVs).  

ERIC Educational Resources Information Center

|This report describes the skills required in the operation of an amphibious air cushion vehicle (ACV) in Army tactical and logistic missions. The research involved analyzing ACV characteristics, operating requirements, environmental effects, and results of a simulation experiment. The analysis indicates that ACV operation is complicated by an…

McKnight, A. James; And Others

14

The Development and Testing of a Control Decoupler for Air Cushion Vehicles.  

National Technical Information Service (NTIS)

For an air cushion vehicle with rudders located well behind the center of gravity, a decoupler eliminates the yaw moment created by the rudders so that the rudder force can be used to control side motion. The necessary countermoment is provided by the dif...

R. A. Miller F. J. Hannigan

1966-01-01

15

Linear analysis of the heave dynamics of a bag and finger air cushion vehicle skirt  

NASA Astrophysics Data System (ADS)

A linear analysis of the heave dynamics of an air-cushion vehicle bag and finger skirt is presented. A simplified geometry is considered; this is a two-dimensional section of the skirt without interior compartmentation. The bag is modeled as a membrane having distributed mass and viscoelasticity, and the fingers are modeled as rigid bodies having both mass and moment of inertia. A finite-element technique is used to discretize the equations of motion of the bag, but otherwise standard linear analysis techniques are used to obtain predictions of frequency response and stability characteristics. The stability results confirm the experimental observation that the dominant factor controlling the onset of skirt bounce is the bag-to-cushion pressure ratio.

Ma, T.; Sullivan, P. A.

1986-09-01

16

A Feasibility Study of an Integrated Mobile Data Collection Platform Using an Air Cushion Vehicle. Volume I.  

National Technical Information Service (NTIS)

This is a study report on the feasibility of using the Bell Aerospace Company air cushion vehicle (Voyageur) as a mobile data collection platform in the Arctic. Specifically, the report covers seven areas where this vehicle would serve usefully in support...

J. A. Hatchwell R. A. Lenton

1972-01-01

17

Air Cushion Vehicle Demonstration in Bethel, Alaska: Costs, Performance, and Impact (Results of a One-Year Demonstration).  

National Technical Information Service (NTIS)

Air Cushion Vehicles (ACV) are a special class of hovercraft that operate on the so called 'ground effect'. This report is an evaluation of the costs, performance and impacts of a one-year demonstration of two ACVs used to provide transportation services ...

O. McCall M. Scalzo

1982-01-01

18

Complete flow field computation around an ACV (air-cushion vehicle) using 3D VOF with Lagrangian propagation in computational domain  

Microsoft Academic Search

In this study an algorithm and a 3D solver is developed to solve the flow field around air-cushion vehicles (ACV) in vicinity of free surface. A single set of dimensionless equations is derived to handle both liquid and air phases in viscous 3D incompressible free surface flows in general curvilinear coordinates. The momentum equations are solved using the SIMPLE method

A. H. Nikseresht; M. M. Alishahi; H. Emdad

2008-01-01

19

Air cushion craft development, first revision  

NASA Astrophysics Data System (ADS)

The development of air cushion craft from their inception to the present day is described. Both aerostatic craft known as air cushion vehicles and surface effect ships as well as aerodynamic craft such as wing-in-ground effect vehicles are covered. The various available theories, empirical laws, and experimental data were brought together and expressed in unified form. Emphasis is given to reducing the data and analysis to their simplest forms for easy understanding and isolation of fundamental parameters. Currently operational craft, those still in their construction jigs, or in some cases those still on the drawing board are assessed and compared to the basic theories to give a measure of the state-of-the-art. Such topics as performance, propulsion, ride quality, and high speed aerodynamic craft are included.

Mantle, P. J.

1980-01-01

20

Investigation of Seal Materials and Configurations for High Speed Air Cushion Vehicles.  

National Technical Information Service (NTIS)

Air flow characteristics through openings provided by single and multiple metal or rubber skirts (labyrinths) situated above a bed surface were established for low pressure systems up to one psig. Single skirting of both types exhibits the standard etheor...

H. J. Reynolds

1969-01-01

21

Analysis of Trunk Flutter in an Air Cushion Landing System.  

National Technical Information Service (NTIS)

This report deals with explaining the occurrence of flutter in the Air Cushion Landing System (ACLS) trunks and suggesting means of suppressing it. Observations of flutter in several ACLS trunks indicate that the flutter is caused by the interaction betwe...

A. B. Boghani R. B. Fish

1979-01-01

22

Duct effects on the heave stability of plenum air cushions  

Microsoft Academic Search

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

M. J. Hinchey; P. A. Sullivan

1978-01-01

23

Wave propagation effects on the heave dynamics of large air cushion platforms  

NASA Astrophysics Data System (ADS)

Acoustic effects on the heave dynamics of large air cushion platforms are explored theoretically. The models developed for an axisymmetric geometry show that when the cushion air is fed centrally through an orifice feed hole the stable pressure-flow operating region can be much smaller than that indicated by the commonly used lumped capacitance model which by definition totally ignores acoustic effects.

Hinchey, M. J.; Sullivan, P. A.; Dupuis, A.

1982-08-01

24

Ground-borne vibration generated by vehicles crossing road humps and speed control cushions  

Microsoft Academic Search

Road humps and speed cushions are used to control vehicle speeds in residential areas. Ground-borne vibrations are produced when vehicles pass over these profiles and in some cases they can reach perceptible levels in adjacent buildings. This paper describes a study to assess the size and nature of these vibrations. Measurements of peak particle velocity have been taken alongside a

G. R Watts; V. V Krylov

2000-01-01

25

Simulation of an Air Cushion Vehicle.  

National Technical Information Service (NTIS)

This report describes the components, architecture, and operations of the ACV-LC real-time digital simulation. The system configuration is described in detail, including the pilot station controls and displays. The mathematical model of the equations of m...

J. F. Loud

1977-01-01

26

Control Systems for Platform Landings Cushioned by Air Bags.  

National Technical Information Service (NTIS)

The report presents an exploratory mathematical study of control systems for airdrop platform landings cushioned by airbags. The basic theory of airbags is reviewed and solutions to special cases are noted. A computer program is presented, which calculate...

E. W. Ross

1987-01-01

27

Control systems for platform landings cushioned by air bags  

Microsoft Academic Search

This report presents an exploratory mathematical study of control systems for airdrop platform landings cushioned by airbags. The basic theory of airbags is reviewed and solutions to special cases are noted. A computer program is presented, which calculates the time-dependence of the principal variables during a landing under the action of various control systems. Two existing control systems of open-loop

Edward W. Ross

1987-01-01

28

Experimental Investigation of Air Cushion Flutter Using a Two- Dimensional Trunk Model.  

National Technical Information Service (NTIS)

This program was an in-house project, to test the effectiveness of flutter control elements on an air cushion trunk. A single inelastic trunk carcass was used throughout the program. Individual elements were added to change the stiffness or mass of the fa...

P. C. Vorum

1984-01-01

29

Air cushion action at the distal end of above-knee stump with a prosthetic socket  

Microsoft Academic Search

The air cushion action over the distal end of residual limb with a prosthetic socket was investigated by experimental measurements of the air pressure during standing and walking and by computational simulation based on finite element methods. The air pressure at the distal-end cavity during walking was found to be in the range of -20 kPa to 17 kPa. The

Ming Zhang; Arthur F. T. Mak; Johnnes Mak

1998-01-01

30

Control systems for platform landings cushioned by air bags  

NASA Astrophysics Data System (ADS)

This report presents an exploratory mathematical study of control systems for airdrop platform landings cushioned by airbags. The basic theory of airbags is reviewed and solutions to special cases are noted. A computer program is presented, which calculates the time-dependence of the principal variables during a landing under the action of various control systems. Two existing control systems of open-loop type are compared with a conceptual feedback (closed-loop) system for a fairly typical set of landing conditions. The feedback controller is shown to have performance much superior to the other systems. The feedback system undergoes an interesting oscillation not present in the other systems, the source of which is investigated. Recommendations for future work are included.

Ross, Edward W.

1987-07-01

31

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

Microsoft Academic Search

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

Engi

2006-01-01

32

Speed control with end cushion for high speed air cylinder  

DOEpatents

A high speed air cylinder in which the longitudinal movement of the piston within the air cylinder tube is controlled by pressurizing the air cylinder tube on the accelerating side of the piston and releasing pressure at a controlled rate on the decelerating side of the piston. The invention also includes a method for determining the pressure required on both the accelerating and decelerating sides of the piston to move the piston with a given load through a predetermined distance at the desired velocity, bringing the piston to rest safely without piston bounce at the end of its complete stroke.

Stevens, Wayne W. (Idaho Falls, ID); Solbrig, Charles W. (Idaho Falls, ID)

1991-01-01

33

Speed control with end cushion for high speed air cylinder  

DOEpatents

A high speed air cylinder in which the longitudinal movement of the piston within the air cylinder tube is controlled by pressurizing the air cylinder tube on the accelerating side of the piston and releasing pressure at a controlled rate on the decelerating side of the piston. The invention also includes a method for determining the pressure required on both the accelerating and decelerating sides of the piston to move the piston with a given load through a predetermined distance at the desired velocity, bringing the piston to rest safely without piston bounce at the end of its complete stroke. 4 figs.

Stevens, W.W.; Solbrig, C.W.

1989-06-20

34

External combustion slidable vane motor with air cushions  

SciTech Connect

This patent describes an external combustion sliding-vane engine comprising the following: a motor member including means for compressing ambient air and means for expanding the combusted gas resulting from the combustion of fuel in the compressed air; a combustion member for receiving compressed air from the motor member, mixing the fuel with compressed air, igniting the mixture and burning the fuel, and delivering the combusted gas to the motor member; a shaft connecting the compression and expanding means for delivering power by means of an external drive shaft; the motor member further including cylindrical center bodies, hollow external structures surrounding and enclosing corresponding ones of the center bodies, flanges supporting the center bodies and hollow external structures for relative rotation between the shaft axis. Each center body and corresponding hollow external structure is positioned between a corresponding pair of adjacent flanges. The external hollow structures and the center bodies have continuously curved surfaces positioned to face each other, and radially extending vane means extending between each pair of adjacent flanges at circumferentially spaced locations. Each vane means extends from an outer facing surface of a corresponding center body to an inner facing surface of a corresponding external hollow structure to define circumferentially spaced sealed spaces between the flanges and the circumferential facing surfaces.

David, C.V.

1987-06-16

35

The Fluid-Structure Interaction in Supporting a Thin Flexible Cylindrical Web with AN Air Cushion  

NASA Astrophysics Data System (ADS)

The mechanics of the fluid-structure interaction between a thin flexible web, wrapped around a cylindrical drum (reverser), and the air cushion formed by external pressurization through the holes of this drum is analyzed. Derivation of a ``new'' theory for the moderately large deflections of a thin cylindrical shell to model the web is presented. This theory allows for large web deflections, while using a self-adjusting strain-free reference state for the web in order to keep the circumferential web tension around a constant level. The theory also incorporates the redistribution of the in-plane stress resultants in the axial and shear directions using the Airy stress function. The air-flow is averaged over the height direction of the web-reverser clearance. The surface area of the pressure holes is averaged locally over the total reverser surface. The resulting equations are a modified form of the Navier-Stokes and mass balance equations with nonlinear source terms. The coupled fluid-structure system is solved numerically. The mechanics of the interaction between the web deflections and the air cushion generated by the reverser is explained. The effects of the problem parameters on the overall equilibrium are presented. Parameter distributions which cause the web to contact the reverser are identified, and suggestions are made to avoid this state.

Müftü, S.; Cole, K. A.

1999-08-01

36

Numerical simulation of the flow in a conduit, in the presence of a confined air cushion  

NASA Astrophysics Data System (ADS)

A rectangular conduit with a closed end has water flowing in/out at the other end. The water level at the open end has an imposed sinusoidal movement. When this level is higher than the ceiling of the conduit, a certain mass of air is trapped under the ceiling. In a previous article (T.D. Nguyen, La Houille Blanche, No. 2, 1990), it was supposed that this air is flowing out freely through the ceiling, so the relative pressure at the water surface is zero, and the water hammer at the dead end of the conduit was calculated when the conduit was thoroughly filled. In this article, it is supposed that the trapped air is compressed isothermally or adiabatically. The set of equations is resolved (water continuity and movement equations, air state equation) by supposing a regime of flow at each section (section submerged or not), a certain value for the air pressure and by using the sweep method to determine the water flow characteristics. The air volume calculated by iteration must converge, and the calculated regimes at each section (submerged or free) must agree with the supposed regimes. The simulation is performed first with a horizontal conduit then with an inclined conduit. As expected, adiabatic compression gives higher pressure than isothermal compression. The simulation shows also that when there is an air cushion, compared with the case when air is flowing out freely, the shock of the water hammer at the closed end of the conduit is significantly reduced. This method is aimed at calculating the flow with entrapped air in the inlet/outlet tunnel of a hydroelectric plant, or in sewer system pipe when a sudden discharge surge (due to turbin opening/closing or to urban storm) changes a previously free-surface flow in a mostly full-pipe flow, but with some air entrapped under the ceiling. Copyright

Nguyen, Trieu Dong

1999-02-01

37

Air-Cushion Effect in the Short-Pulse Shock Initiation of Explosives  

NASA Astrophysics Data System (ADS)

When thin flyer plates are used to shock initiate high explosive (HE) any air present ahead of the flyer may cause a significant desensitization of the HE. The effect of the air in cushioning the impact of plastic flyers faced with metal films is analyzed here with MACRAME, a code which calculates wave interactions and traces wave propagation. We find that the second air shock into the HE has sufficient pressure to collapse the HE to crystal density or higher. Precompressed regions of HE do not react rapidly when the main impact pulse does arrive. Define y as the depth where the major shock overtakes the precompression wave (for no air y^*arrow 0). For various flyers and air combinations, we compare pressure profiles at y=y^*+?. The shock pressure profile associated with metal film impact may be greatly attenuated at the depth y^*. Density profiles (?(t) at y) show that the shock heating for y>y^* is greater than that for y

Fritz, J. N.; Kennedy, J. E.

1997-07-01

38

Air cushion effect in the short-pulse initiation of explosives  

NASA Astrophysics Data System (ADS)

When thin flyer plates are used to shock initiate high explosive (HE), any air present ahead of the flyer may cause a significant desensitization of the HE. The effect of the air in cushioning the impact of plastic flyers faced with metal films is analyzed here with MACRAME, a code which calculates wave interactions and traces wave propagation. We find that the second air shock into the HE has sufficient pressure to collapse the HE to crystal density or higher. Precompressed regions of HE do not react rapidly when the main impact pulse does arrive. Define y* as the depth where the major shock overtakes the precompression wave (for no air y*-->0). For various flyers and air combinations, we compare pressure profiles at y=y*+?. The shock pressure profile associated with metal film impact may be greatly attenuated at the depth y*. Density profiles (?(t) at y) show that the shock heating for y>y* is greater than that for y

Fritz, J. N.; Kennedy, J. E.

1998-07-01

39

Air cushion effect in the short-pulse initiation of explosives  

SciTech Connect

When thin flyer plates are used to shock initiate high explosive (HE), any air present ahead of the flyer may cause a significant desensitization of the HE. The effect of the air in cushioning the impact of plastic flyers faced with metal films is analyzed here with MACRAME, a code which calculates wave interactions and traces wave propagation. The authors find that the second air shock into the HE has sufficient pressure to collapse the HE to crystal density or higher. Precompressed regions of HE do not react rapidly when the main impact pulse does arrive. Define y{sup *} as the depth where the major shock overtakes the precompression wave (for no air y{sup *} {r_arrow} 0). For various flyers and air combinations, the authors compare pressure profiles at y = y{sup *} + {epsilon}. The shock pressure profile associated with metal film impact may be greatly attenuated at the depth y{sup *}. Density profiles (p(t) at y) show that the shock heating for y > y{sup *} is greater than that for y < y{sup *}.

Fritz, J.N.; Kennedy, J.E.

1997-08-01

40

Design criteria for light high speed desert air cushion vehicles  

Microsoft Academic Search

An evaluation is made of the applicability and prospective performance of ACVs in trans-Saharan cargo transport, in view of the unique characteristics of the dry sand environment. The lightweight\\/high-speed ACV concept envisioned is essentially ground effect aircraftlike, with conventional wheels as a low-speed backup suspension system. A propeller is used in ground effect cruise. Attention is given to the effects

B. E. Abulnaga

1986-01-01

41

Effect of a responsive skirt on air cushion vehicle seakeeping  

NASA Astrophysics Data System (ADS)

The skirt system, which will be excited to make a response motion under the outer disturbance, is treated as a passive control system, and the longitudinal motion equations of ACV are derived according to the control principle. The influence of the skirt response in waves on ACVs seaworthiness is analyzed in the paper. Some results are gotten that the greater vertical deflexion of skirt will make the response of heave, pitch motion and acceleration of the craft decreased a lot, but the horizontal deflexion will go the opposite way. The natural frequency of skirt plays an important role in seaworthiness improvement, the adoption of lower frequency skirt can make the frequency band of craft motion response narrower effectively. The matching of skirt parameters of bow and stern has a certain effect too.

Zhou, W. L.; Ma, T.

42

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

SciTech Connect

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.

Engi, Dennis

2006-10-01

43

MICRO AIR VEHICLE SURVEILLANCE PLATFORM  

Microsoft Academic Search

This paper discusses the design and development of a Micro Air Vehicle (MAV) platform focusing on aerodynamic design; material durability and precision; and propulsion system integration. The purpose of the MAV is to compete in the surveillance mission at the 2006 International Micro Air Vehicle Competition (IMAVC). A low Reynolds number airfoil and planform was designed and validated through wind

Michael Koelemay; Andrew Streett; Michael Reid; Shane Healey; Matteo Blanc; Joe Calandro; Josh Joseph; John Lemmon; Adam Gillis

2006-01-01

44

Large Number of Air Vehicles Simulation (LNAVSIM).  

National Technical Information Service (NTIS)

The Large Number of Air Vehicles Simulation (LNAVSIM) is an environment for modeling, planning, and simulating an air war. LNAVSIM addresses the Air Force's need for command and control tools for unmanned combat air vehicles (ucavs) and unmanned air vehic...

R. Johnson

2003-01-01

45

Design of an SRM-based actuator for high-performance steering vane control on the landing craft air cushion (LCAC) hovercraft  

Microsoft Academic Search

This work presents a switched reluctance motor (SRM) based actuator for use on the landing craft air cushion (LCAC), to replace the existing hydraulic systems that control the steering vanes. The proposed SRM-based actuator enables the reduction of complexity, weight, and maintenance associated with conventional hydraulic systems. The proposed actuator consists of an SRM and a high-efficiency screw with suitable

J. Han; X. Zhou; A. von Jouanne; A. Wallace; D. Marckx; G. Hjelmeland

2004-01-01

46

Air cushioned landing craft (LCAC) based ship to shore movement simulation: A decision aid for the amphibious commander. A (SMMAT) application  

Microsoft Academic Search

Amphibious forces are the enabling force of choice to globally project rapid and sustainable combat power in the littoral. Whether delivering supplies and equipment for military operations or for humanitarian or disaster relief, the air cushioned landing craft (LCAC) is the primary surface ship-to-shore movement craft. The time needed to transfer the forces ashore may be critical to operational success

Edward P. Kearns III

1994-01-01

47

Calibration of an Axial Fan at Various Power Settings for Use on a Quarter Scale XC-8A Air Cushion Model.  

National Technical Information Service (NTIS)

A method was developed to measure volume flow from electrically powered fans during model testing of a dynamically scaled, quarter-scale XC-8A air cushion model. To measure the volume flow during model operation, the static pressure at a point along the f...

D. L. Fischer

1980-01-01

48

Micro air vehicle navigation system  

Microsoft Academic Search

A description of the design, operation, and test results of a Micro-Electro-Mechanical (MEMS)-based navigation system for the Micro Air Vehicle (MAV) is presented. The MAV is a small Unmanned Aerial Vehicle (UAV) built by Honeywell. It is one of the first applications to use Honeywell's new HG1930 MEMS inertial measurement unit (IMU). The raw IMU measurements are transmitted via a

B. B. Mohr; D. L. Fitzpatrick

2008-01-01

49

THE NRL MITE AIR VEHICLE  

Microsoft Academic Search

Micro Air Vehicles (MAVs) offer the promise of affordably expendable, covert sensor platforms for a range of close-in situational awareness activities. Since 1996, the US Naval Research Laboratory (NRL) has been developing technologies that will enable Navy-relevant missions with the smallest practical MAVs. This effort includes the development and integration of sensors, avionics, and advanced intelligent autopilots for flight control,

James Kellogg; Christopher Bovais; Jill Dahlburg; Richard Foch; John Gardner; Adam Sciambi; William Spears; Donald Srull; Carol Sullivan

2001-01-01

50

Unmanned air vehicles: new challenges in design  

Microsoft Academic Search

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

T. J. Cord; S. Newbern

2001-01-01

51

Air quality impacts of electric vehicles  

Microsoft Academic Search

The potential air quality impacts of electric vehicles in North Carolina are evaluated considering both air pollution reductions from less use of internal combustion engine vehicles and also additional air pollution at electric power plants. Using a consumer survey of 260 households, estimates of EV sales at $20,000 per vehicle, $15,000 and $10,000 are first made. EV purchases are classified

D. T. Hartgen; M. Murthy; N. N. Y. Cheung; J. A. Patten

1994-01-01

52

Effect of Air Cushions under Floating Offshore Structures. International Conference on the Behaviour of Offshore Structures, BOSS '97 (8th). Held in Delft, The Netherlands on July 7-10, 1997. Volume 2. Hydrodynamics.  

National Technical Information Service (NTIS)

A computational method to determine the effects of air cushions on the behavior of large floating structures in waves is described. The method is based on linear three-dimensional potential theory using linearized adiabatic law for the air pressures in th...

J. H. Vugts

1997-01-01

53

Clean fuel vehicles: The air pollution solution  

Microsoft Academic Search

Clean fuels for cars and trucks can do more for air quality, and do it sooner, than any other alternative on the drawing boards today. In much of the country, vehicles are the single biggest cause of air pollution. It`s not the industrial smoke stacks, but the tail pipes on cars that foul the air. Ninety percent of the carbon

Meotti

1995-01-01

54

Enabling Technologies for Nano Air Vehicles.  

National Technical Information Service (NTIS)

This project investigated several areas with the aim of improving performance and operational use of nano air vehicles (NAVs) by understanding fundamental operating principles and developing key technologies. The project developed plasma actuators for thr...

J. D. Jacob

2009-01-01

55

Flexible-Wing-Based Micro Air Vehicles.  

National Technical Information Service (NTIS)

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 st...

P. G. Ifju D. A. Jenkins S. Ettinger Y. S. Lian W. Shyy M. R. Waszak

2002-01-01

56

Motor Vehicles, Air Pollution, and Climate Change  

Microsoft Academic Search

Despite years of technical progress, motor vehicles continue to be a leading cause of environmental damage in the United States. For example, today's cars and trucks are the largest source of air pollution in many urban areas. US motor vehicles also account for 25 percent of the nation's carbon emissions, more than most countries emit from all sources combined. Fortunately,

Jason Mark

2000-01-01

57

Intelligent Unmanned Air Vehicle Flight Systems  

Microsoft Academic Search

This paper describes an intelligent autonomous airborne flight capability that is being used as a test bed for future technology development. The unmanned air vehicles (UAVs) fly under autonomous control of both an onboard computer and an autopilot. The onboard computer provides the mission control and runs the autonomous Intelligent Controller (IC) software while the autopilot controls the vehicle navigation

Jodi A. Miller; Paul D. Minear; Albert F. Niessner; Anthony M. DeLullo; Brian R. Geiger; Lyle N. Long; Joseph F. Horn

2007-01-01

58

Cooperative Control for Autonomous Air Vehicles  

Microsoft Academic Search

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

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

59

Lighter-Than-Air Vehicles.  

National Technical Information Service (NTIS)

This report provides a comprehensive overview of all current and planned programs funded within the Department of Defense (DoD) to include aerostats, airships, and rigid-aeroshell variable buoyancy vehicles.

2012-01-01

60

Air cushioned landing craft (LCAC) based ship to shore movement simulation: A decision aid for the amphibious commander. A (SMMAT) application  

NASA Astrophysics Data System (ADS)

Amphibious forces are the enabling force of choice to globally project rapid and sustainable combat power in the littoral. Whether delivering supplies and equipment for military operations or for humanitarian or disaster relief, the air cushioned landing craft (LCAC) is the primary surface ship-to-shore movement craft. The time needed to transfer the forces ashore may be critical to operational success and is an important planning consideration. Many factors complicate accurate prediction of this time. Even so, various commanders must use the best available information, given mission priorities and resource and capability limitations, to make numerous tradeoff decisions in planning and executing the movement of forces. A simulation toolbox, the simulated mobility modeling and analysis toolbox (SMMAT), is introduced, and a robust LCAC ship-to-shore simulation model is developed as an extension to SMMAT. This model provides the commander a prediction and tradeoff analysis tool for planning and executing the projection of power ashore.

Kearns, Edward P., III

1994-09-01

61

Aluminum-air batteries for vehicles  

Microsoft Academic Search

The aluminum-air battery is an advanced electrochemical energy source in the early stages of development. The battery is potentially capable of providing an electric vehicle with the range, acceleration, and rapid refueling capability of today's automobile. The Lawrence Livermore National Laboratory leads this DOE-funded program with a major part of the research being conducted by industrial laboratories. Peak cell energy

E. Behrin; J. F. Cooper

1981-01-01

62

Membrane wing aerodynamics for micro air vehicles  

Microsoft Academic Search

The aerodynamic performance of a wing deteriorates considerably as the Reynolds number decreases from 106 to 104. In particular, flow separation can result in substantial change in effective airfoil shape and cause reduced aerodynamic performance. Lately, there has been growing interest in developing suitable techniques for sustained and robust flight of micro air vehicles (MAVs) with a wingspan of 15cm

Yongsheng Lian; Wei Shyy; Dragos Viieru; Baoning Zhang

2003-01-01

63

Vehicle overturning vulnerability from air blast loads  

NASA Astrophysics Data System (ADS)

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.

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

1984-08-01

64

Covert air vehicle 2003 LDRD final report.  

SciTech Connect

This report describes the technical work carried out under a 2003 Laboratory Directed Research and Development project to develop a covert air vehicle. A mesoscale air vehicle that mimics a bird offers exceptional mobility and the possibility of remaining undetected during flight. Although some such vehicles exist, they are lacking in key areas: unassisted landing and launching, true mimicry of bird flight to remain covert, and a flapping flight time of any real duration. Current mainstream technology does not have the energy or power density necessary to achieve bird like flight for any meaningful length of time; however, Sandia has unique combustion powered linear actuators with the unprecedented high energy and power density needed for bird like flight. The small-scale, high-pressure valves and small-scale ignition to make this work have been developed at Sandia. We will study the feasibility of using this to achieve vehicle takeoff and wing flapping for sustained flight. This type of vehicle has broad applications for reconnaissance and communications networks, and could prove invaluable for military and intelligence operations throughout the world. Initial tests were conducted on scaled versions of the combustion-powered linear actuator. The tests results showed that heat transfer and friction effects dominate the combustion process at 'bird-like' sizes. The problems associated with micro-combustion must be solved before a true bird-like ornithopter can be developed.

Spletzer, Barry Louis; Callow, Diane Schafer; Salton, Jonathan Robert; Fischer, Gary John

2003-11-01

65

Autonomous unmanned air vehicles (UAV) techniques  

NASA Astrophysics Data System (ADS)

The UAVs (Unmanned Air Vehicles) have great potentials in different civilian applications, such as oil pipeline surveillance, precision farming, forest fire fighting (yearly), search and rescue, boarder patrol, etc. The related industries of UAVs can create billions of dollars for each year. However, the road block of adopting UAVs is that it is against FAA (Federal Aviation Administration) and ATC (Air Traffic Control) regulations. In this paper, we have reviewed the latest technologies and researches on UAV navigation and obstacle avoidance. We have purposed a system design of Jittering Mosaic Image Processing (JMIP) with stereo vision and optical flow to fulfill the functionalities of autonomous UAVs.

Hsu, Ming-Kai; Lee, Ting N.

2007-04-01

66

Advanced Marine Vehicles: A Review.  

National Technical Information Service (NTIS)

This paper provides an overview of hull form design practices as applied by NAVSEA 501 in the design of hydrofoils, small waterplane area twin hulls (SWATH), surface effect ships, and air cushion vehicles for the U.S. Navy. General design considerations a...

M. R. Bebar C. G. Kennell W. N. White D. R. Lavis

1986-01-01

67

Texas Crash Cushion Trailer.  

National Technical Information Service (NTIS)

The Texas crash cushion trailer consists of an array of 20-gauge 55-gallon steel drums, a trailer frame, a set of wheels and a trailer hitch. Each steel drum has eight-inch holes cut in the top and bottom. When this crash cuchion trailer is properly attac...

L. E. Brown

1974-01-01

68

Zinc air battery development for electric vehicles  

SciTech Connect

This report summarizes the results of research conducted during the sixteen month continuation of a program to develop rechargeable zinc-air batteries for electric vehicles. The zinc-air technology under development incorporates a metal foam substrate for the zinc electrode, with flow of electrolyte through the foam during battery operation. In this soluble'' zinc electrode the zincate discharge product dissolves completely in the electrolyte stream. Cycle testing at Lawrence Berkeley Laboratory, where the electrode was invented, and at MATSI showed that this approach avoids the zinc electrode shape change phenomenon. Further, electrolyte flow has been shown to be necessary to achieve significant cycle life (> 25 cycles) in this open system. Without it, water loss through the oxygen electrode results in high-resistance failure of the cell. The Phase I program, which focused entirely on the zinc electrode, elucidated the conditions necessary to increase electrode capacity from 75 to as much as 300 mAh/cm{sup 2}. By the end of the Phase I program over 500 cycles had accrued on one of the zinc-zinc half cells undergoing continuous cycle testing. The Phase II program continued the half cell cycle testing and separator development, further refined the foam preplate process, and launched into performance and cycle life testing of zinc-air cells.

Putt, R.A.; Merry, G.W. (MATSI, Inc., Atlanta, GA (United States))

1991-07-01

69

Zinc air battery development for electric vehicles  

NASA Astrophysics Data System (ADS)

This report summarizes the results of research conducted during the sixteen month continuation of a program to develop rechargeable zinc-air batteries for electric vehicles. The zinc-air technology under development incorporates a metal foam substrate for the zinc electrode, with flow of electrolyte through the foam during battery operation. In this 'soluble' zinc electrode the zincate discharge product dissolves completely in the electrolyte stream. Cycle testing at Lawrence Berkeley Laboratory, where the electrode was invented, and at MATSI showed that this approach avoids the zinc electrode shape change phenomenon. Further, electrolyte flow has been shown to be necessary to achieve significant cycle life (greater than 25 cycles) in this open system. Without it, water loss through the oxygen electrode results in high resistance failure of the cell. The Phase 1 program, which focused entirely on the zinc electrode, elucidated the conditions necessary to increase electrode capacity from 75 to as much as 300 mAh/sq cm. By the end of the Phase 1 program over 500 cycles had accrued on one of the zinc-zinc half cells undergoing continuous cycle testing. The Phase 2 program continued the half cell cycle testing and separator development, further refined the foam preplate process, and launched into performance and cycle life testing of zinc-air cells.

Putt, R. A.; Merry, G. W.

1991-07-01

70

Conceptual design of flapping-wing micro air vehicles  

Microsoft Academic Search

Traditional micro air vehicles (MAVs) are miniature versions of full-scale aircraft from which their design principles closely follow. The first step in aircraft design is the development of a conceptual design, where basic specifications and vehicle size are established. Conceptual design methods do not rely on specific knowledge of the propulsion system, vehicle layout and subsystems; these details are addressed

J P Whitney; R J Wood

2012-01-01

71

Air Vehicle Simulator: an Application for a Cable Array Robot  

Microsoft Academic Search

The development of autonomous air vehicles can be an expensive research pursuit. To alleviate some of the financial burden of this process, we have constructed a system consisting of four winches each attached to a central pod (the simulated air vehicle) via cables — a cable-array robot. The system is capable of precisely controlling the three dimensional position of the

Kane Usher; Graeme J. Winstanley; Peter I. Corke; Dirk Stauffacher; Ryan Carnie

2005-01-01

72

A Diagnostic System for Air Brakes in Commercial Vehicles  

Microsoft Academic Search

The safe operation of vehicles on roads depends, among other things, on a properly functioning brake system. Air brake systems are widely used in commercial vehicles such as trucks, tractor-trailers, and buses. In these brake systems, compressed air is used as the energy transmitting medium to actuate the foundation brakes mounted on the axles. In this paper, a model-based diagnostic

Shankar C. Subramanian; Swaroop Darbha; K. R. Rajagopal

2006-01-01

73

The development of aluminum-air batteries for electric vehicles  

Microsoft Academic Search

Progress made toward the development of a viable aluminum-air battery system is presented. The general aluminum\\/air reaction is discussed. Results from aluminum anode and air cathode experiments are presented. Solids separation technology, a heat exchanger unit, and cell design are also discussed. The projected specific energy and power of the battery can provide electric vehicle driving ranges comparable to those

A. S. Homa; E. J. Rudd

1989-01-01

74

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

75

Interior view Beale Air Force Base, Perimeter Acquisition Vehicle ...  

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

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

76

Unsteady Low Reynolds Number Aerodynamics for Micro Air Vehicles (MAVs).  

National Technical Information Service (NTIS)

This work introduces the Micro Air Vehicle (MAV) problem from the viewpoint of aerodynamics. Water tunnels are assessed as tools for MAV aerodynamics. The design, construction and instrumentation of RB's 'Horizontal Free-surface Water Tunnel' is documente...

M. V. Ol

2010-01-01

77

Uninhibited Combat Air Vehicles and Commercial Satellites: 'The Missing Link'.  

National Technical Information Service (NTIS)

In the not too far distant future, a new Uninhabited Combat Air Vehicle (UCAV), a cousin of the UAVs flying over Bosnia today, is destined to fly the most sensitive and dangerous missions the USAF is expected to accomplish. This vehicle, though uninhabite...

M. Nichols

1998-01-01

78

DURABILITY OF A HYBRID AIR-LAND VEHICLE  

Microsoft Academic Search

A small hybrid vehicle has been developed and tested that is capable of flying, crawling, and transitioning between aerial and terrestrial locomotion modes. The Morphing Micro Air-Land Vehicle is a 16 inch wingspan craft proposed for advanced reconnaissance missions. Earlier versions of MMALV included several sources of low durability. Original prototypes relied on standard RC servos (modified for continuous rotation)

Richard J. Bachmann; Ravi Vaidyanathan; Roger D. Quinn; Peter G. Ifju

2005-01-01

79

Design and analysis of a gyroscopically controlled micro air vehicle  

NASA Astrophysics Data System (ADS)

Much of the current research on micro air vehicle design relies on aerodynamic forces for attitude control. The aerodynamic environment in which micro air vehicles operate is characterized by a low Reynolds number and is not fully understood, resulting in decreased performance and efficiency when compared to large-scale vehicles. In this work, we propose a new rotary-wing micro air vehicle design that utilizes gyroscopic dynamics for attitude control. Unlike traditional micro air vehicles where attitude control moments are generated by aerodynamic control surfaces, the proposed vehicle will leverage the existing angular momentum of its rotating components to generate gyroscopic moments for controlling attitude. We explore this paradigm in an effort to reduce mechanical complexity that is inherent in blade pitch modulation mechanisms such as the swashplate, and to increase agility and possibly even efficiency when compared to state-of-the-art micro vertical-take-off-and-landing vehicles. The evolution of the mechanical design, including the evaluation of three prototypes that explore the use of gyroscopic attitude control, is presented along with a comprehensive dynamic and aerodynamic model of the third prototype. Two controllers that utilize gyroscopic moments are developed and tested in simulation. In addition, several experiments were performed using a VICON motion tracking system and off-board control. These results will also be presented.

Thorne, Christopher Everett

80

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

SciTech Connect

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.

Habors, D.T.; Hossain, M.

1998-09-01

81

Honeywell's organic air vehicle chemical-biological sensing platform  

NASA Astrophysics Data System (ADS)

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 unique benefit for CB sampling and in-flight analysis is the Honeywell family of Organic Air Vehicles (OAVs). This vehicle with its ability to hover and stare has the unique ability among UAVs to collect and analyze chem-bio samples from a specific location over extended periods of time. Such collections are not possible with other micro-air-vehicles (MAVs) that only operate in fly-by mode. This paper describes some of the Honeywell OAV features that are conducive to CB detection.

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

2004-12-01

82

Prototype air bag restraint for use in patrol vehicles  

SciTech Connect

An air bag has been designed and laboratory tested for use in existing police vehicles that will restrain a person if he or she becomes violent. The device will prevent self-injury and protect the vehicle and officer. The device does not pose a suffocation hazard and can be quickly and easily inflated or deflated by the officer from the front seat. The device is ready for field testing.

Marts, D.J.; Barker, S.G.

1995-03-01

83

Effect of Intake Air Filter Condition on Vehicle Fuel Economy  

SciTech Connect

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%.

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

2009-02-01

84

The aluminum-air battery for electric vehicles - An update  

NASA Astrophysics Data System (ADS)

The development of aluminum-air batteries as mechanically rechargeable power sources to be used in electric vehicles is discussed. The chemistry of the aluminum-air battery, which has a potential for providing the range, acceleration and rapid refueling capability of contemporary automobiles and is based on the reaction of aluminum metal with atmospheric oxygen in the presence of an aqueous sodium hydroxide/sodium aluminate electrolyte, is examined, and it is pointed out that the electric vehicle would be practically emissionless. The battery development program at the Lawrence Livermore National Laboratory, which includes evaluations of electrochemical and chemical phenomena, studies of the economics and energy balance of a transportation system based on aluminum, and power cell design and performance analysis, is presented. It is concluded that although difficult problems must be overcome before the technical and economic feasibility of aluminum-air batteries for electric vehicles can be established, projections indicate that the aluminum-air vehicle is potentially competitive with internal combustion vehicles powered by synthetic liquid fuels.

1980-11-01

85

The aluminum-air battery for electric vehicle propulsion  

Microsoft Academic Search

This report reviews the status of aluminum-air battery development and discusses the use of aluminum as a recyclable electrochemical fuel. The battery combines high specific energy (above 300 Wh\\/kg) and specific power (150-200 W\\/kg) with the capability of rapid refueling by addition of reactants. The objective is a commercially-feasible, general-purpose electric vehicle. Progress is reported in the scale-up of aluminum-air

J. F. Cooper; R. V. Homsy; J. H. Landrum

1980-01-01

86

Study of long term options for electric vehicle air conditioning  

SciTech Connect

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.

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

1991-07-01

87

Collaborative tactical behaviors for autonomous ground and air vehicles  

NASA Astrophysics Data System (ADS)

Tactical behaviors for autonomous ground and air vehicles are an area of high interest to the Army. They are critical for the inclusion of robots in the Future Combat System (FCS). Tactical behaviors can be defined at multiple levels: at the Company, Platoon, Section, and Vehicle echelons. They are currently being defined by the Army for the FCS Unit of Action. At all of these echelons, unmanned ground vehicles, unmanned air vehicles, and unattended ground sensors must collaborate with each other and with manned systems. Research being conducted at the National Institute of Standards and Technology (NIST) and sponsored by the Army Research Lab is focused on defining the Four Dimensional Real-time Controls System (4D/RCS) reference model architecture for intelligent systems and developing a software engineering methodology for system design, integration, test and evaluation. This methodology generates detailed design requirements for perception, knowledge representation, decision making, and behavior generation processes that enable complex military tactics to be planned and executed by unmanned ground and air vehicles working in collaboration with manned systems.

Albus, James; Barbera, Anthony; Scott, Harry; Balakirsky, Stephen

2005-05-01

88

Flush Air Data Sensing System for Trans-Atmospheric Vehicles  

NASA Astrophysics Data System (ADS)

With the emergence of multiple companies attempting to tap the space tourism market, as well as NASA's return to the moon initiative, an inexpensive but reliable means of determining wind relative vehicle attitude is becoming a necessity. The traditional means of obtaining air data (altitude, Mach number, angles of attack and sideslip) using fixed pitot probes and directional flow vanes is not viable for collecting data on high supersonic and hypersonic vehicles, due to the high temperatures and dynamic pressures. The solution is to use a matrix of flush mounted pressure ports on the vehicle nose or on an outboard wing leading edge. Since the ports will be located behind a detached shock wave at supersonic velocities, the temperatures will remain substantially lower. A Flush Air Data Sensing (FADS) system can also be used for subsonic conditions, although it must be calibrated for the effects of the vehicle geometry. The physics of air behavior and the mathematics of the solution algorithm will be presented. Several relevant examples of planned vehicles will be presented.

Ellsworth, Joel

2006-10-01

89

Mechanically refuelable zinc/air electric vehicle cells  

NASA Astrophysics Data System (ADS)

Refuelable zinc/air batteries have long been considered for motive as well as stationary power because of a combination of high specific energy, low initial cost, and the possibility of mechanical recharge by electrolyte exchange and additions of metallic zinc. In this context, advanced slurry batteries, stationary packed bed cells, and batteries offering replaceable cassettes have been reported recently. The authors are developing self-feeding, particulate-zinc/air batteries for electric vehicle applications. Emissionless vehicle legislation in California motivated efforts to consider a new approach to providing an electric vehicle with long range (400 km), rapid refueling (10 minutes) and highway safe acceleration - factors which define the essential functions of common automobiles. Such an electric vehicle would not compete with emerging secondary battery vehicles in specialized applications (commuting vehicles, delivery trucks). Rather, different markets would be sought where long range or rapid range extension are important. Examples are: taxis, continuous-duty fork-lift trucks and shuttle busses, and general purpose automobiles having modest acceleration capabilities. In the long range, a mature fleet would best use regional plants to efficiently recover zinc from battery reaction products. One option would be to use chemical/thermal reduction to recover the zinc. The work described focuses on development of battery configurations which efficiently and completely consume zinc particles, without clogging or changing discharge characteristics.

Noring, J.; Gordon, S.; Maimoni, A.; Spragge, M.; Cooper, J. F.

1992-12-01

90

Dioxin-receptor ligands in urban air and vehicle exhaust.  

PubMed Central

The ability of extracts of urban air and vehicle exhaust particulates to bind to the dioxin receptor has been determined. It was shown that such extracts do contain significant amounts of dioxin-receptor binding activity. The level of dioxin-receptor binding found in ambient air reflects its pollution level as determined by mutagenic activity. Furthermore, it was shown that the extracts of both urban air and vehicle exhaust particulates could provoke the induction of cytochrome P450IA1 in cultured rat hepatoma cells. Chemical fractionation of the extracts revealed that the majority of the dioxin-receptor binding activity from urban air and gasoline vehicle samples fractionated with the polycyclic aromatic compounds. However, unknown polycyclic aromatic compounds were responsible for the majority of the binding activity measured. In the case of diesel vehicle exhausts, the majority of the dioxin-receptor binding activity was found to be associated with nitro-polycyclic aromatic compounds. Studies with a variety of diesel fuels showed that the amount of dioxin-receptor ligands present in exhaust emissions are fuel-dependent and that substantial amounts of dioxin-receptor ligands are present in the semivolatile phase of exhaust emissions.

Mason, G G

1994-01-01

91

Contactless charging for electric vehicles with a large air gap  

Microsoft Academic Search

An induction coupler with 100mm wide air gap is being developed for contactless charging of electric vehicles with power levels up to 3kW. This will enable convenient opportunity charging at stops and maximise battery life and mileage. A core was found to be necessary, and using an iterative method, the core design was optimised for optimum coupling was found for

Terry Chi Young Ho; Ben Gomersall; Li Ran

2011-01-01

92

Autonomous terrain-following for unmanned air vehicles  

Microsoft Academic Search

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

Raza Samar; Abdur Rehman

2011-01-01

93

Vector Field Path Following for Miniature Air Vehicles  

Microsoft Academic Search

In this paper, a method for accurate path following for miniature air vehicles is developed. The method is based on the notion of vector fields, which are used to generate desired course inputs to inner-loop attitude control laws. Vector field path following control laws are developed for straight-line paths and circular arcs and orbits. Lyapunov stability arguments are used to

Derek R. Nelson; D. Blake Barber; Timothy W. Mclain; Randal W. Beard

2007-01-01

94

Adaptive path planning algorithm for cooperating unmanned air vehicles  

SciTech Connect

An adaptive path planning algorithm is presented for cooperating Unmanned Air Vehicles (UAVs) that are used to deploy and operate land-based sensor networks. The algorithm employs a global cost function to generate paths for the UAVs, and adapts the paths to exceptions that might occur. Examples are provided of the paths and adaptation.

Cunningham, C T; Roberts, R S

2001-02-08

95

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

Microsoft Academic Search

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

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

2001-01-01

96

Natural language command of an autonomous micro-air vehicle  

Microsoft Academic Search

Natural language is a flexible and intuitive modality for conveying directions and commands to a robot but presents a number of computational challenges. Diverse words and phrases must be mapped into structures that the robot can understand, and elements in those structures must be grounded in an uncertain environment. In this paper we present a micro-air vehicle (MAV) capable of

Albert S. Huang; Stefanie Tellex; Abraham Bachrach; Thomas Kollar; Deb Roy; Nicholas Roy

2010-01-01

97

Micro air vehicle: configuration, analysis, fabrication, and test  

Microsoft Academic Search

This paper presents the development of two electrically powered micro air vehicle (MAV) prototypes with wingspans of 380 and 360 mm, respectively. A miniature flight control system is constructed using small and light components. A vision system consisting of a micro radio frequency (RF) transmitter and a miniature vision-receiving antenna with a low-noise amplifier is designed, which exhibits advantages over

Huaiyu Wu; Dong Sun; Zhaoying Zhou

2004-01-01

98

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

SciTech Connect

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.

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

2001-08-28

99

Morphing Unmanned Air Vehicle Intelligent Shape and Flight Control  

Microsoft Academic Search

This paper develops and demonstrates a complete methodology for the control of a morphing unmanned air vehicle. The shape learning is done with a modified episodic Re- inforcement Learning algorithm, which employs an adaptive grid to improve the search performance and accuracy of learning the optimal shape change policy. The shape control, which uses Reinforcement Learning, and the trajectory tracking

John Valasek; Amanda Lampton; Monika Marwaha

2009-01-01

100

Zinc air fuel cell for industrial and specialty vehicles  

Microsoft Academic Search

Metallic Power has demonstrated a regenerative zinc air fuel cell for applications in industrial and specialty vehicles. The fuel cell uses zinc pellets and atmospheric oxygen to generate electric current; the reaction product is zinc oxide, which is collected in a tank. In its present stage of development the 36 V fuel cell will deliver approximately 6 kWh, with a

S. Smedley

2000-01-01

101

Pioneer unmanned air vehicle accomplishments during Operation Desert Storm  

Microsoft Academic Search

The accomplishments and lessons learned of the Pioneer Unmanned Air Vehicle (UAV) during operation Desert Shield and Desert Storm are described. The Pioneer UAV has been deployed with three branches of the U.S. military (USA, USN, and USMC) for the past four years. Although the system has compiled more than 6,000 flight hours, the recent conflict in the Persian Gulf

James H. Christner

1991-01-01

102

62 FR 28932 - Control of Air Pollution From Motor Vehicles and New Motor Vehicle Engines; Modification of...  

Federal Register 2010, 2011, 2012, 2013

...40 CFR Part 86 Control of Air Pollution From Motor Vehicles and New Motor...CFR Part 86 [FRL-5827-6] Control of Air Pollution From Motor Vehicles and New Motor...thresholds) with those of the California Air Resources Board (CARB) OBD II...

1997-05-28

103

60 FR 52734 - Control of Air Pollution From New Motor Vehicles and New Motor Vehicle Engines: Voluntary...  

Federal Register 2010, 2011, 2012, 2013

...40 CFR Parts 51, 85 and 86 Control of Air Pollution From New Motor Vehicles and New...AMS-FRL-5311-2] RIN 2060-AF75 Control of Air Pollution From New Motor Vehicles and New...an on-going process to achieve cleaner air in the OTR. The OTR States submitted...

1995-10-10

104

Some Design Principles of Ground Effect Machines Section F - Cushion Contributions to Stability.  

National Technical Information Service (NTIS)

A review is undertaken of some of the more important elementary relationships which determine the influence of the air cushion on the pitch, heave, and roll stability of ground effect machines. The analyses presented yield only rough approximations of the...

H. R. Chaplin A. G. Ford

1967-01-01

105

The real air quality benefits of gaseous-fueled vehicles.  

SciTech Connect

This paper provides a justification for prominent inclusion of currently available gaseous-fueled vehicles (i.e., vehicles powered by propane, sometimes called liquefied petroleum gas [LPG], or natural gas--chiefly, methane--stored onboard the vehicle in gaseous or liquid state but combusted as a gas) in the mix of strategies to (a) reduce public exposure to toxic and fine particulate emissions in the urbanized areas of the developing world and (b) achieve local and regional improvements in ozone air quality. It also presents estimates of associated emission reduction credits into the future. Important considerations discussed are the location of fine particle and toxic emissions in congested urban areas, and the location and timing of ozone precursor emissions, with emphasis on how gaseous-fueled vehicles' role in the relationship among and magnitude of these variables differs from that of their conventionally-fueled counterparts. Efforts to enhance the measurement and quantification of gaseous-fuel benefits are also described.

Saricks, C. L.

2002-03-28

106

Aluminum Air Battery for Electric Vehicle Propulsion.  

National Technical Information Service (NTIS)

The status of aluminum-air battery development and the use of aluminum as a recyclable electrochemical fuel are discussed. The battery combines high specific energy (above 300 Wh/kg) and specific power (150 to 200 W/kg) with the capability of rapid refuel...

J. F. Cooper R. V. Homsy J. H. Landrum

1980-01-01

107

A zinc-air battery and flywheel zero emission vehicle  

SciTech Connect

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.

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

1995-10-03

108

76 FR 17487 - Protection of Stratospheric Ozone: New Substitute in the Motor Vehicle Air Conditioning Sector...  

Federal Register 2010, 2011, 2012, 2013

...Part 82 Protection of Stratospheric Ozone: New Substitute in the Motor Vehicle Air Conditioning Sector Under the Significant New Alternatives Policy (SNAP) Program; Final...2060-AP11 Protection of Stratospheric Ozone: New Substitute in the Motor Vehicle Air...

2011-03-29

109

Powering future vehicles with the refuelable zinc/air battery  

SciTech Connect

A recent road test at LLNL underscored the zinc/air battery`s capacity to give electric vehicles some of the attractive features of gas-driven cars: a 400-km range between refueling, 10-minute refueling, and highway-safe acceleration. Developed at Lawrence Livermore National Laboratory, the battery weights only one-sixth as much as standard lead/acid batteries and occupies one-third the space, yet costs less per mile to operate. What`s more, because the battery is easily refuelable, it promises trouble-free, nearly 24-hour-a-day operation for numerous kinds of electric vehicles, from forklifts to delivery vans and possibly, one day, personal automobiles. The test of a Santa Barbara Municipal Transit bus with a hybrid of zinc/air and lead/acid batteries capped a short development period for the zinc/air battery. The test run indicated the zinc/air battery`s potential savings in vehicle weight from 5.7 to 4.0 metric tons, in battery weight from 2.0 to 0.3 metric tons, in battery volume from 0.79 to 0.25 m{sup 3}, and in electricity cost from 5.6 cents per mile to 4.7 cents per mile. The power, however, remains the same.

NONE

1995-10-01

110

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

NASA Astrophysics Data System (ADS)

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.

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

1980-02-01

111

Surface wave scattering on a drone air vehicle  

Microsoft Academic Search

Recent radar-cross-section (RCS) measurements on a generic drone air vehicle conducted at 34 GHz revealed a strong surface-wave scattering mechanism associated with the shadowed side, in contrast with expectations. Two-dimensional inverse synthetic aperture radar (ISAR) images illustrating the scattering features are presented with the objective of documenting the experimental results. The measurements were conducted over a frequency band of 3.175

M. Benson; D. Hilliard; D. Mensa; K. Oh; W. Yates

1993-01-01

112

Air liquefaction and enrichment system propulsion in reusable launch vehicles  

SciTech Connect

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. 5 refs.

Bond, W.H.; Yi, A.C. [Rockwell Int. Corp., Downey, CA (United States)

1994-07-01

113

Air liquefaction and enrichment system propulsion in reusable launch vehicles  

NASA Astrophysics Data System (ADS)

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.

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

1994-07-01

114

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

Microsoft Academic Search

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

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

1980-01-01

115

Conceptual design of flapping-wing micro air vehicles.  

PubMed

Traditional micro air vehicles (MAVs) are miniature versions of full-scale aircraft from which their design principles closely follow. The first step in aircraft design is the development of a conceptual design, where basic specifications and vehicle size are established. Conceptual design methods do not rely on specific knowledge of the propulsion system, vehicle layout and subsystems; these details are addressed later in the design process. Non-traditional MAV designs based on birds or insects are less common and without well-established conceptual design methods. This paper presents a conceptual design process for hovering flapping-wing vehicles. An energy-based accounting of propulsion and aerodynamics is combined with a one degree-of-freedom dynamic flapping model. Important results include simple analytical expressions for flight endurance and range, predictions for maximum feasible wing size and body mass, and critical design space restrictions resulting from finite wing inertia. A new figure-of-merit for wing structural-inertial efficiency is proposed and used to quantify the performance of real and artificial insect wings. The impact of these results on future flapping-wing MAV designs is discussed in detail. PMID:22498507

Whitney, J P; Wood, R J

2012-04-12

116

Air vehicle integration issues and considerations for CLAS successful implementation  

NASA Astrophysics Data System (ADS)

Over the last decade, Northrop Grumman Corporation under internal and DoD funding, and others, have been working on integration of RF antennas into load-bearing aircraft structures. This multidisciplinary effort, collectively referred to as Conformal Load-bearing Antenna Structures (CLAS), requires concurrent consideration of structural and antenna performance issues and has involved a team consisting of avionics, structures, material, and manufacturing expertise. From the published articles to date it could be argued that the technology has had some spectacular success in its initial stages but not much has been published about the issues raised by CLAS that would still need to be addressed and solved for final technology inclusion in an operational air-vehicle. Presented are some key results from the Air Force Research Laboratory's (AFRL) Smart Skins Structures Technology Demonstrator (S3TD) program that while funded from the Air Vehicles Directorate looked at the total picture of integration from a multidisciplilnary standpoint. Issues related to airframe integration are also discussed that need further study and evaluation before CLAS can be sanctioned as a viable future DoD technology. Such topics, in no particular order of priority are 1) airframe CLAS panel location, 2) airframe configuration issues, 3) EMI/lightning issues, and 4) repair issues and supportability, 5) panel design enhancement, risks, and issues.

Lockyer, Allen J.; Alt, Kevin H.; Kudva, Jayanth N.; Tuss, James

2001-06-01

117

Mixed Initiative Control of Unmanned Air and Ocean Going Vehicles: Models, Tools and Experimentation.  

National Technical Information Service (NTIS)

The problem of mixed initiative control of unmanned air and ocean going vehicles is discussed, a formal mixed initiative control framework for networked vehicles is introduced and tools for operational deployments are presented, together with lessons lear...

G. Goncalves J. Borges de Sousa

2007-01-01

118

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

Microsoft Academic Search

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

Shaohua Yang

2003-01-01

119

78 FR 32223 - Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards  

Federal Register 2010, 2011, 2012, 2013

The U.S. Environmental Protection Agency (``EPA'') is announcing an extension of the public comment period for the proposed rule ``Control of Air Pollution from Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards'' (the proposed rule is hereinafter referred to as ``Tier 3''). EPA published a notice of proposed rulemaking, which included a request for comment, in the Federal Register......

2013-05-29

120

Design Analysis of an Aluminum-Air Battery for Vehicle Operations. Transportation Systems Research.  

National Technical Information Service (NTIS)

The objective of the study reported was to perform a detailed configuration analysis of an aluminum-air battery, evaluate various automobile propulsion systems utilizing the Al-air battery, and estimate the performance and cost of vehicles incorporating t...

C. L. Hudson D. J. Whisler E. Behrin J. D. Salisbury R. L. Wood

1983-01-01

121

Zinc air battery development for electric vehicles. Final report  

SciTech Connect

This report summarizes the results of research conducted during the sixteen month continuation of a program to develop rechargeable zinc-air batteries for electric vehicles. The zinc-air technology under development incorporates a metal foam substrate for the zinc electrode, with flow of electrolyte through the foam during battery operation. In this ``soluble`` zinc electrode the zincate discharge product dissolves completely in the electrolyte stream. Cycle testing at Lawrence Berkeley Laboratory, where the electrode was invented, and at MATSI showed that this approach avoids the zinc electrode shape change phenomenon. Further, electrolyte flow has been shown to be necessary to achieve significant cycle life (> 25 cycles) in this open system. Without it, water loss through the oxygen electrode results in high-resistance failure of the cell. The Phase I program, which focused entirely on the zinc electrode, elucidated the conditions necessary to increase electrode capacity from 75 to as much as 300 mAh/cm{sup 2}. By the end of the Phase I program over 500 cycles had accrued on one of the zinc-zinc half cells undergoing continuous cycle testing. The Phase II program continued the half cell cycle testing and separator development, further refined the foam preplate process, and launched into performance and cycle life testing of zinc-air cells.

Putt, R.A.; Merry, G.W. [MATSI, Inc., Atlanta, GA (United States)

1991-07-01

122

Motions and Added Resistance Due to Waves of Surface Effect Ships. RTO Meeting Proceedings 15 'Fluid Dynamics of Vehicles Operating Near or in the Air-Sea Interface'. Held in Amsterdam, The Netherlands on October 5-8, 1998.  

National Technical Information Service (NTIS)

This paper presents a computational methods for motions and added resistance due to waves of Surface Effect Ships. The computed added resistance only includes the added resistance of the air cushion. This added resistance component was believed to be the ...

J. C. Moulijn

1999-01-01

123

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

Microsoft Academic Search

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

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

2005-01-01

124

Utilizing adaptive wing technology in the control of a micro air vehicle  

Microsoft Academic Search

Evolution of the design of micro air vehicles (MAVs) towards miniaturization has been severely constrained by the size and mass of the electronic components needed to control the vehicles. Recent research, experimentation, and development in the area of smart materials have led to the possibility of embedding control actuators, fabricated from smart materials, in the wing of the vehicle, reducing

William R. Null; Matthew G. Wagner; Sergey V. Shkarayev; Wayne C. Jouse; Keith M. Brock

2002-01-01

125

40 CFR 86.1832-01 - Optional equipment and air conditioning for test vehicles.  

Code of Federal Regulations, 2013 CFR

...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 § 86.1832-01...

2013-07-01

126

Flow sensitive actuators for micro-air vehicles  

NASA Astrophysics Data System (ADS)

A macrofiber piezoelectric composite has been developed for boundary layer management of micro-air vehicles (MAVs). Specifically, a piezoelectric composite that is capable of self-sensing and controlling flow has been modeled, designed, fabricated, and tested in wind tunnel studies to quantify performance characteristics, such as the velocity field response to actuation, which is relevant for actively managing boundary layers (laminar and transition flow control). A nonlinear piezoelectric plate model was utilized to design the active structure for flow control. The dynamic properties of the piezoelectric composite actuator were also evaluated in situ during wind tunnel experiments to quantify sensing performance. Results based on velocity field measurements and unsteady pressure measurements show that these piezoelectric macrofiber composites can sense the state of flow above the surface and provide sufficient control authority to manipulate the flow conditions for transition from laminar to turbulent flow.

Kumar, V.; Hays, M.; Fernandez, E.; Oates, W.; Alvi, F. S.

2011-10-01

127

Pioneer unmanned air vehicle accomplishments during Operation Desert Storm  

NASA Astrophysics Data System (ADS)

The accomplishments and lessons learned of the Pioneer Unmanned Air Vehicle (UAV) during operation Desert Shield and Desert Storm are described. The Pioneer UAV has been deployed with three branches of the U.S. military (USA, USN, and USMC) for the past four years. Although the system has compiled more than 6,000 flight hours, the recent conflict in the Persian Gulf is the first opportunity to demonstrate its true value in a combat scenario. In a relatively short time (42 days), 307 flights and 1,011 flight hours were completed on Operation Desert Storm. This, coupled with the accuracy of various weapons systems that Pioneer observed/cued for, resulted in timely target engagements. The Pioneer deployment and accomplishments on operations Desert Shield and Desert Storm are chronicled. Various employment methods, tactics, doctrine, and lessons learned are presented.

Christner, James H.

1991-12-01

128

Evaluation of the Air Force's Alternative Fuel Vehicle Program in Complying with Executive Order 13149.  

National Technical Information Service (NTIS)

The Air Force must comply with Executive Order (E.O.) 13149, which includes cutting its vehicle fleet's petroleum fuel usage 20 percent by 2005. This thesis examines the Air Force's current alternative fuel vehicle (AFV) program, which is centered around ...

J. D. Ketchum

2001-01-01

129

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

Microsoft Academic Search

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

S. M. Aceves

1996-01-01

130

Unsteady Low-Reynolds Number Aerodynamics for Micro Air Vehicles (MAVs).  

National Technical Information Service (NTIS)

This report documents recent progress in in-house research in the AFRL Air Vehicles Directorate on unsteady aerodynamics at low Reynolds number. The application is the aerodynamics and flight dynamics of agile Micro Air Vehicles, to include flapping-wings...

M. V. Ol

2007-01-01

131

On some classes of control-oriented model of air-breathing hypersonic vehicles  

Microsoft Academic Search

The system modeling and controller design for air-breathing hypersonic vehicles have always been one of the most highly challenging tasks to the development of hypersonic flight technologies due to the unique characteristics of the vehicle dynamics. In this paper, we first provide an overview of three major classes of control-oriented models of air-breathing hypersonic vehicles in existing literatures. Moreover, explicitly

Cai Guangbin; Duan Guangren; Hu Changhua

2010-01-01

132

H-CANYON AIR EXHAUST TUNNEL INSPECTION VEHICLE DEVELOPMENT  

SciTech Connect

The H-Canyon at Savannah River Site is a large concrete structure designed for chemical separation processes of radioactive material. The facility requires a large ventilation system to maintain negative pressure in process areas for radioactive contamination control and personnel protection. The ventilation exhaust is directed through a concrete tunnel under the facility which is approximately five feet wide and 8 feet tall that leads to a sand filter and stack. Acidic vapors in the exhaust have had a degrading effect on the surface of the concrete tunnels. Some areas have been inspected; however, the condition of other areas is unknown. Experience from historical inspections with remote controlled vehicles will be discussed along with the current challenge of inspecting levels below available access points. The area of interest in the exhaust tunnel must be accessed through a 14 X 14 inch concrete plug in the floor of the hot gang valve corridor. The purpose for the inspection is to determine the condition of the inside of the air tunnel and establish if there are any structural concerns. Various landmarks, pipe hangers and exposed rebar are used as reference points for the structural engineers when evaluating the current integrity of the air tunnel.

Minichan, R.; Fogle, R.; Marzolf, A.

2011-05-24

133

78 FR 20881 - Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards...  

Federal Register 2010, 2011, 2012, 2013

The EPA is announcing two public hearings to be held for the proposed rule ``Control of Air Pollution from Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards'' (the proposed rule is hereinafter referred to as ``Tier 3''), which will be published separately in the Federal Register. The hearings will be held in Philadelphia, PA on April 24, 2013 and in Chicago, IL on April 29, 2013.......

2013-04-08

134

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

NASA Astrophysics Data System (ADS)

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.

Orlowski, Christopher T.; Girard, Anouck R.

2012-05-01

135

MAV2008: 1st US-Asian Demonstration and Assessment of Micro Air Vehicle (MAV) and Unmanned Ground Vehicle (UGV) Technology. Schedule of Events, Abstracts and Profiles.  

National Technical Information Service (NTIS)

The activity brought together teams from around the world to address these challenges for micro air vehicles (MAVs): flight, cooperative flight, cooperation with ground-based vehicles, loitering, and sensing surroundings. The test scenario mission was to ...

A. R. Upadhya E. Stierna V. Shubha

2008-01-01

136

Characterization of Vehicle Use in Fine Air Quality Control Regions.  

National Technical Information Service (NTIS)

Under contract to the Emission Control Technology Division of the U.S. Environmental Protection Agency, Technical Service Corporation (TSC) has compiled data, estimates and projections of vehicle population and use by vehicle age and type, for each of the...

J. A. Eldon D. B. Hunsaker

1978-01-01

137

Characterization of vehicle use in fine air quality control regions  

Microsoft Academic Search

Under contract to the Emission Control Technology Division of the U.S. Environmental Protection Agency, Technical Service Corporation (TSC) has compiled data, estimates and projections of vehicle population and use by vehicle age and type, for each of these cities: Chicago, Denver, Los Angeles, Houston, and Phoenix. As motor vehicle emissions are sensitive to temperature, humidity, and barometric pressure, meteorological data

J. A. Eldon; D. B. Hunsaker

1978-01-01

138

Partial camera automation in an unmanned air vehicle.  

PubMed

The present study focused on an intelligent, semiautonomous, interface for a camera operator of a simulated unmanned air vehicle (UAV). This interface used system "knowledge" concerning UAV motion in order to assist a camera operator in tracking an object moving through the landscape below. The semiautomated system compensated for the translations of the UAV relative to the earth. This compensation was accompanied by the appropriate joystick movements ensuring tactile (haptic) feedback of these system interventions. The operator had to superimpose self-initiated joystick manipulations over these system-initiated joystick motions in order to track the motion of a target (a driving truck) relative to the terrain. Tracking data showed that subjects performed substantially better with the active system. Apparently, the subjects had no difficulty in maintaining control, i.e., "following" the active stick while superimposing self-initiated control movements over the system-interventions. Furthermore, tracking performance with an active interface was clearly superior relative to the passive system. The magnitude of this effect was equal to the effect of update-frequency (2-5 Hz) of the monitor image. The benefits of update frequency enhancement and semiautomated tracking were the greatest under difficult steering conditions. Mental workload scores indicated that, for the difficult tracking-dynamics condition, both semiautomation and update frequency increase resulted in less experienced mental effort. For the easier dynamics this effect was only seen for update frequency. PMID:11541093

Korteling, J E; van der Borg, W

1997-03-01

139

Aeroelastic analysis and optimization of membrane micro air vehicle wings  

NASA Astrophysics Data System (ADS)

Fixed-wing micro air vehicles are difficult to fly, due to their low Reynolds number, low aspect ratio nature: flow separation erodes wing efficiency, the wings are susceptible to rolling instabilities, wind gusts can be the same size as the flight speed, the range of stable center of gravity locations is very small, etc. Membrane aeroelasticity has been identified has a tenable method to alleviate these issues. These flexible wing structures are divided into two categories: load-alleviating or load-augmenting. This depends on the wing's topology, defined by a combination of stiff laminate composite members overlaid with a membrane sheet, similar to the venation patterns of insect wings. A series of well-validated variable-fidelity static aeroelastic models are developed to analyze the working mechanisms (cambering, washout) of membrane wing aerodynamics in terms of loads, wing deformation, and flow structures, for a small set of wing topologies. Two aeroelastic optimization schemes are then discussed. For a given wing topology, a series of numerical designed experiments utilize tailoring of laminate orientation and membrane pre-tension. Further generality can be obtained with aeroelastic topology optimization: locating an optimal distribution of laminate shells and membrane skin throughout the wing. Both optimization schemes consider several design metrics, optimal compromise designs, and experimental validation of superiority over baseline designs.

Stanford, Bret Kennedy

140

Zinc\\/air battery R and D. Zinc\\/air engineering analysis for electrical vehicles, task 3  

Microsoft Academic Search

This report is an examination and analysis of the zinc-air system as the motive power source for electric vehicle propulsion. Various versions of the zinc-air system and operating schemes along with their advantages and disadvantages are discussed. Baseline cost calculations are also presented in order to compare the cost effectiveness of each of the systems. The treatise is conceptual in

M. Klein; S. Viswanathan

1986-01-01

141

Zinc\\/air battery R and D zinc\\/air engineering analysis for electrical vehicles: Tasks III, Final report  

Microsoft Academic Search

This report is an examination and analysis of the zinc-air system as the motive power source for electric vehicle propulsion. Various versions of the zinc-air system and operating schemes along with their advantages and disadvantages are discussed. Baseline cost calculations are also presented in order to compare the cost effectiveness of each of the systems. The treatise is conceptual in

M. Klein; S. Viswanathan

1986-01-01

142

Membrane and adaptively-shaped wings for micro air vehicles  

NASA Astrophysics Data System (ADS)

Micro air vehicles (MAVs), with wing span of 15 cm or less and flight speed around 10 m/s, have many applications in both civilian and military areas. The Reynolds number based on the given parameters is around 10 4, which often yields insufficient lift-to-drag ratio. Furthermore, one expects the unsteady effect to be noticeable for such flight vehicles. The flexible wing has been demonstrated to exhibit favorable characteristics such as passive adaptation to the flight; environment and delayed stall. The present study focuses on developing computational and modeling capabilities to better understand the MAV aerodynamics. Both flexible wings, utilizing membrane materials, and adaptively-shaped wings, utilizing piezo-actuated flaps, have been studied. In the adaptively-shaped wing study, we use piezo-actuated flaps to actively control the flow. We assess the impacts of the flap geometry, flapping amplitude, and turbulence; modeling on the flow structure with a parallel experimental effort. The membrane wing uses a passive control mechanism to delay the stall angle and to provide a smoother flight platform. Our study focuses on the mutual interactions between the membrane wing and its surrounding viscous flow. We compare the lift-to-drag ratio and the flow structure between the flexible wing and the corresponding rigid wing. We also investigate the aerodynamic characteristics associated with the low Reynolds number and low aspect ratio wing. To assist our study, we propose an automatic and efficient moving grid technique to facilitate the fluid and structure interaction computations; we also present a dynamic membrane model to study the intrinsic large deformation of the flexible membrane wing. Solutions obtained from the three-dimensional Navier-Stokes equations are presented to highlight, the salient features of the wing aerodynamics. Besides the aerodynamic study, we also perform shape optimization to improve the membrane wing performance. Since direct optimization of a membrane wing is too time consuming to be practical, we optimize a surrogate rigid wing model based on an integrated optimization algorithm, which consists of a Navier-Stokes solver, an automatic grid generation tool; and a gradient-based optimizer. Then, we assess the membrane wing performance based on the outcome from the surrogate model. Our numerical results confirm that the membrane wing exhibits consistent improvement in the lift-to-drag ratio with the surrogate model.

Lian, Yongsheng

143

Health Benefits of Reducing Particulate Air Pollution from Heavy Duty Vehicles.  

National Technical Information Service (NTIS)

The U.S. Environmental Protection Agency (U.S.EPA) recently promulgated regulations to reduce air pollution from heavy-duty vehicles. This article reports the estimated health benefits of reductions in ambient particulate matter (PM) concentrations associ...

B. Timin B. J. Hubbell G. Stella N. Possiel T. Koman T. J. Fox

2007-01-01

144

Capability and Interface Assessment of Gaming Technologies for Future Multi-Unmanned Air Vehicle Systems.  

National Technical Information Service (NTIS)

This report evaluates several gaming technologies and details their applicability to future control concepts for multiple unmanned air vehicle systems (UAS). Current gaming technologies evaluated include Real-Time Strategy (RTS) games, which require the s...

M. Gacy

2011-01-01

145

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

146

Evaluation of the Thorax of Manduca sexta for Flapping Wing Micro Air Vehicle Applications.  

National Technical Information Service (NTIS)

The tobacco hornworm hawkmoth (Manduca sexta) provides an excellent model from which to garner knowledge pertaining to the development of a Flapping Wing Micro Air Vehicle (FWMAV). Insect-sized FWMAVs will be used by the future warfighter for reconnaissan...

A. C. Hollenbeck

2012-01-01

147

Wing Force & Moment Characterization of Flapping Wings for Micro Air Vehicle Application.  

National Technical Information Service (NTIS)

This paper presents a general method for investigating the unsteady aerodynamics of flapping wings for micro air vehicle application. For this purpose, a dynamically scaled robotic flapper was designed and fabricated which can flap the wings in a desired ...

Z. A. Khan S. K. Agrawal

2005-01-01

148

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

149

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

150

Unsteady Aerodynamics for Micro Air Vehicles (Aerodynamique instable pour micro-vehicules aeriens).  

National Technical Information Service (NTIS)

Recognizing that the flowfield environments encountered by Micro Air Vehicles (MAVs) are fundamentally unsteady - whether for fixed-wing, rotary- wing or flapping-wing configurations, AVT-149 seeks to address fundamental questions in unsteady low Reynolds...

2010-01-01

151

Some Recent Developments in Wireless Power Transmission to Micro Air Vehicles  

NASA Astrophysics Data System (ADS)

Requirements and new techniques are described for wireless power transmission to micro air vehicles. These techniques involve the use of high-density and multiple-function rectennas, pulsed continuous wave transmission, and a move to higher frequencies.

Alden, A.; Bouliane, P.; Zhang, M.

2005-04-01

152

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

153

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

154

Literature Review on Bounding Flight in Birds With Applications to Micro Uninhabited Air Vehicles.  

National Technical Information Service (NTIS)

Bounding flight is an intermittent flight pattern observed in small birds, in which periods of flapping flight alternate with periods of wings- folded flight. It has been suggested that this flight pattern could be adopted by micro uninhabited air vehicle...

H. A. Keating

2002-01-01

155

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

PubMed

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

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

2011-08-01

156

Use of Vortex Flows for the Propulsion of Micro-Air and Sea Vehicles.  

National Technical Information Service (NTIS)

Recent interest in flapping-wing propulsion, in particular for hovering or low-speed flight of micro air vehicles, has led to a renewed interest in the measurement and prediction of unsteady, vortex-dominated flows. The proposed vehicles typically operate...

K. D. Jones M. F. Platzer

2003-01-01

157

Coevolution of Form and Function in the Design of Micro Air Vehicles  

Microsoft Academic Search

This paper discusses approaches to cooperative coevolution of form and function for autonomous vehicles, specifically ev olving morphology and control f or an autonomous micro air vehicle (MAV). The evolution of a sensor s uite with minimal size, weight, and power requirements, and reactive strategies for collision-free navigation for the simulated MAV is described. Results are presented for several different

Magdalena D. Bugajska; Alan C. Schultz

2002-01-01

158

Scatter pattern calculations and determination performance limitations of existing air defense systems for intercepting hypersonic vehicles  

Microsoft Academic Search

The article describes a methodology for determination performance limitations of existing air defense systems for intercepting a hypersonic vehicles. The methodology used results of scatter pattern calculations for hypersonic unmanned aerial vehicle X-51. A numerical 3D-model of the UAV was developed by author on the basis of public sources. The surface of the UAV is represented by a set of

Evgeny Markin; Intellcom LLC

2012-01-01

159

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

ERIC Educational Resources Information Center

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…

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

2008-01-01

160

Fugitive particulate air emissions from off-road vehicle maneuvers at military training lands  

Technology Transfer Automated Retrieval System (TEKTRAN)

Military training lands used for off-road vehicle maneuvers may be subject to severe soil loss and air quality degradation as a result of severe wind erosion. The objective of this study was to measure suspended particulate matter resulting from various different vehicle training scenarios. Soil s...

161

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

ERIC Educational Resources Information Center

|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…

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

2008-01-01

162

Design and Development of Autonomous Uninhabited Air Vehicles at ITB: Challenges and Progress Status  

Microsoft Academic Search

An uninhabited air vehicle has found diverse applications for both civil and military missions. To achieve the stated mission, the vehicle needs to have a certain level of autonomy to maintain its stability following a desired path under embedded guidance, navigation and control al- gorithm. To meet the increasingly more stringent operation requirements, the UAVs rely less and less on

A. Budiyono

2005-01-01

163

Dynamics and control of a biomimetic single-wing nano air vehicle  

Microsoft Academic Search

This paper describes the Samarai - a rotating mono-wing nano air vehicle (NAV) designed at Lockheed Martin Advanced Technology Laboratories. Challenges uniquely associated with developing this type of vehicle are identified and a dynamic modeling and control synthesis procedure is described for tackling them. It is shown that, by modeling the rotating wing as a lower-complexity spinning disk, and using

Kingsley Fregene; Cortney L. Bolden

2010-01-01

164

21 CFR 872.3540 - OTC denture cushion or pad.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3540 OTC denture cushion or pad. (a) Identification. An OTC denture cushion or pad is a...

2013-04-01

165

Estimates of the cost and energy consumption of aluminum-air electric vehicles  

Microsoft Academic Search

Economic costs and primary energy consumption are estimated for general purpose electric vehicles using aluminum-air propulsion batteries within the time frame of the 1990's (earliest possible date of introduction). For an aluminum-air fuel economy of 36 tonne\\/km\\/kg-Al (optimized low-gallium alloys), a total refueling cost of 5.6 cents\\/km (1979$) was estimated for a 1.27 tonne vehicle. This is equivalent to $2

J. F. Cooper

1980-01-01

166

Robust Longitudinal Flight Controller Design for the Air-breathing Hypersonic Vehicle  

Microsoft Academic Search

The design of a robust longitudinal flight controller for the air-breathing hypersonic vehicle is presented in this paper. The non-standard dynamic characteristics of air-breathing hypesonic flight vehicles together with the aerodynamic effects of hypersonic flight make the flight control of such systems highly challenging. Moreover the wide range of speed during operation and the lack of a broad flight dynamics

Wei Jian-li; Yu Yun-feng

2008-01-01

167

Unmanned air vehicle (UAV) ultra-persitence research  

SciTech Connect

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.

Dron, S. B.

2012-03-01

168

An analysis of aluminum-air battery propulsion systems for passenger vehicles  

Microsoft Academic Search

The performance characteristics of three electric-propulsion systems based on the Al-air battery were analyzed and compared to the internal combustion engine (ICE). In this comparison, the engine and fuel systems of a current five-passenger vehicle were conceptually replaced by three Al-air systems: (1) an Al-air battery-only system, (2) an Al-air battery combined with a nickel-zinc secondary battery for power leveling,

J. D. Salisbury; E. Behrin

1980-01-01

169

Target location by self-organizing autonomous air vehicles  

NASA Astrophysics Data System (ADS)

Target location is a problem where the application of multiple sensors that are geographically distributed can determine or improve the location estimate of a target. If these sensors are capable of cooperative behaviour then the information from each sensor can be autonomously fused to provide an estimate of the target position. The individual sensors may be quite unsophisticated, yet the observation system that is created through cooperation and adaptive networking of these sensors provides sufficient process gain to achieve target location accuracies similar to those of expensive centralized sensor systems. The accuracy of target location estimates depends heavily on the separation distance between the sensors. Large baseline geometry takes advantage of many seemingly unsophisticated bearing measurements that are organised into a coordinated observation system to locate a target. Team formation is one method to address coordination of distributed sensors, data fusion, sensor resource and energy management, and communication link control based on the concept of cooperating machines1,2,3. We apply an algorithm for agent team formation4 inspired by the self-organising behaviour observed in colonies of ants, to the problem of integrating the sensors of a group of networked mini-Autonomous Air Vehicles (AAVs). The mini-AAVs are tasked to locate targets within a region of interest. The challenge we address is to make the location estimation system adaptive to a dynamic environment and robust to failure. Simulation results are presented which address issues in distributed data fusion, sensor resource and energy management, and communication link control, for a group of mini-AAVs.

Brown, Kim; Bowyer, Richard S.; Koks, Don

2002-08-01

170

Efficient target geolocation by highly uncertain small air vehicles  

Microsoft Academic Search

Geolocation of a ground object or target of in- terest from live video is a common task required of small and micro unmanned aerial vehicles (SUAVs and MAVs) in surveillance and rescue applications. However, such vehicles commonly carry low-cost and light-weight sensors providing poor bandwidth and accuracy whose contribution to observa- tions is nonlinear, resulting in poor geolocation performance by

Ben Grocholsky; Michael Dille; Stephen Nuske

2011-01-01

171

Air-conditioning system of an intelligent vehicle-cabin  

Microsoft Academic Search

If vehicles can be more comfortable, safe, energy efficient and humanized, it will be very beneficial. This study introduces an “Airflow Management” technique to control the airflow in the vehicle cabin for the purpose of achieving a regional steady-state temperature. With this new concept, each passenger in a different area of the compartment can be satisfied with respect to his\\/her

K. David Huang; Sheng-Chung Tzeng; Tzer-Ming Jeng; Wing-Ding Chiang

2006-01-01

172

Development of High-Resolution Motor Vehicle Emission Inventories for City-Wide Air Quality Impact Analysis in China  

Microsoft Academic Search

In recent years, large cities in China face severer air pollution due to motor vehicle emissions. Accurate high-resolution emission inventories are essential as they are commonly used in air quality dispersion modeling analysis to determine impacts from motor vehicle emissions and assess the effectiveness of control strategies. This paper presents a case study based on motor vehicle emissions in the

Hui Guo; Hung-Ming Sung; Wei Dai; Qing-Yu Zhang

173

Measurement of in-vehicle volatile organic compounds under static conditions.  

PubMed

The types and quantities of volatile organic compounds (VOCs) inside vehicles have been determined in one new vehicle and two old vehicles under static conditions using the Thermodesorber-Gas Chromatograph/Mass Spectrometer (TD-GC/MS). Air sampling and analysis was conducted under the requirement of USEPA Method TO-17. A room-size, environment test chamber was utilized to provide stable and accurate control of the required environmental conditions (temperature, humidity, horizontal and vertical airflow velocity, and background VOCs concentration). Static vehicle testing demonstrated that although the amount of total volatile organic compounds (TVOC) detected within each vehicle was relatively distinct (4940 microg/m3 in the new vehicle A, 1240 microg/m3 in used vehicle B, and 132 microg/m3 in used vehicle C), toluene, xylene, some aromatic compounds, and various C7-C12 alkanes were among the predominant VOC species in all three vehicles tested. In addition, tetramethyl succinonitrile, possibly derived from foam cushions was detected in vehicle B. The types and quantities of VOCs varied considerably according to various kinds of factors, such as, vehicle age, vehicle model, temperature, air exchange rate, and environment airflow velocity. For example, if the airflow velocity increases from 0.1 m/s to 0.7 m/s, the vehicle's air exchange rate increases from 0.15 h(-1) to 0.67 h(-1), and in-vehicle TVOC concentration decreases from 1780 to 1201 microg/m3. PMID:18062419

You, Ke-wei; Ge, Yun-shan; Hu, Bin; Ning, Zhan-wu; Zhao, Shou-tang; Zhang, Yan-ni; Xie, Peng

2007-01-01

174

Alternative Methods for Flotation Seat Cushion Use.  

National Technical Information Service (NTIS)

Alternative methods of using flotation seat cushions for water crash survivors were identified at the Civil Aeromedical Institute (CAM I). These methods, tested in the CAMI survival tank and a theme park wave pool, were: (1) two people facing each other, ...

G. E. Funkhouser M. H. George

1995-01-01

175

Alternative Methods for Flotation Seat Cushion Use.  

National Technical Information Service (NTIS)

Alternative methods of using flotation seat cushions for water crash survivors were identified at the Civil Aeromedical Institute (CAMI). These methods, tested in the CAMI survival tank and a theme park wave pool were: (1) two people facing each other, ho...

G. E. Funkhouser M. H. George

1995-01-01

176

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

Microsoft Academic Search

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

E. J. Rudd; S. Lott

1990-01-01

177

Experimental Analysis of Propeller Interactions With a Flexible Wing Micro-Air-Vehicle.  

National Technical Information Service (NTIS)

An investigation into the effects of the propeller slipstream on a flexible wing micro-air-vehicle (MAV) was conducted. The Air Force Research Lab, Munitions Directorate designed a man-portable MAV with a 24 in. wingspan and 6 in. root chord to be used fo...

B. J. Gamble

2006-01-01

178

Separation Flight Tests of a Small Unmanned Air Vehicle from a C-130 Transport Aircraft  

Microsoft Academic Search

Unmanned Air Vehicles (UAVs) are increasingly being considered for various roles in the civilian and military communities. Various launch methods have been explored and have been mostly ground based. The desire to investigate the feasibility of launching a UAV from a larger surrogate air platform existed, but had not been explored. As part of a concept demonstration program, NAVAIR's Test

David W. Roberts; Aaron D. Judy

179

Reynolds Number Effects on Thrust Coefficients and PIV for Flapping Wing Micro Air Vehicles.  

National Technical Information Service (NTIS)

For the last several years the Air Force Institute of Technology (AFIT) has conducted research in aerodynamics for flapping wing micro air vehicles (MAVs). The focus of this research was to augment this effort by measuring thrust, velocity, and torque in ...

J. P. Tekell

2012-01-01

180

Comparative Studies on Vehicle Related Policies for Air Pollution Reduction in Ten Asian Countries  

Microsoft Academic Search

Asian countries are facing major air pollution problems due to rapid economic growth, urbanization and motorization. Mortality and respiratory diseases caused by air pollution are believed to be endemic in major cities of these countries. Regulations and standards are the first requirement for reducing emissions from both fixed and mobile sources. This paper emphasizes monitoring problems such as vehicle registration

Keiko Hirota

2010-01-01

181

Operator state estimation for adaptive aiding in uninhabited combat air vehicles  

Microsoft Academic Search

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

Christopher A. Russell

2005-01-01

182

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

NASA Astrophysics Data System (ADS)

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.

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

2012-02-01

183

Design analysis of an aluminum-air battery for vehicle operations. Transportation systems research  

Microsoft Academic Search

The objective of the study reported was to perform a detailed configuration analysis of an aluminum-air battery, evaluate various automobile propulsion systems utilizing the Al-air battery, and estimate the performance and cost of vehicles incorporating these propulsion systems. A preliminary engineering design is performed. A physical model and a cell-performance model of a conceptual mass-produced Al-air battery were constructed and

E. Behrin; R. L. Wood; J. D. Salisbury; D. J. Whisler; C. L. Hudson

1983-01-01

184

A comparison of metal-air batteries for electric vehicle propulsion  

Microsoft Academic Search

A comparison is made among four metal-air systems being considered for future use in commuter electric vehicles. The anode materials are lithium, aluminum, zinc and iron. The lithium-air system is still in an early stage of development. A proposed mechanically rechargeable aluminum-air system is potentially capable of superior performance but its relative cost of ownership and operation is expected to

W. A. Bryant; E. S. Buzzelli

1979-01-01

185

Environmental impacts associated with the aluminum-air battery electric vehicle fuel cycle  

Microsoft Academic Search

The aluminum-air battery concept is discussed, and a scenario is developed which forecasts ten million aluminum-air electric vehicles in the US by the year 2000. An estimation is made regarding the consumption of natural resources and generation of wastes due to the aluminum-air battery's fuel cycle and to the increased demand on the US aluminum industry because of the scenario.

K. J. E

1982-01-01

186

Zinc/air battery R and D. Zinc/air engineering analysis for electrical vehicles, task 3  

NASA Astrophysics Data System (ADS)

This report is an examination and analysis of the zinc-air system as the motive power source for electric vehicle propulsion. Various versions of the zinc-air system and operating schemes along with their advantages and disadvantages are discussed. Baseline cost calculations are also presented in order to compare the cost effectiveness of each of the systems. The treatise is conceptual in nature and is not based on new experimental work.

Klein, M.; Viswanathan, S.

1986-12-01

187

Suppressing Vertical Vibration in Railway Vehicles through Air Spring Damping Control  

NASA Astrophysics Data System (ADS)

To improve the riding comfort of railway vehicles equipped with the air suspension system now in widespread use, we tested a semi-active air suspension control system with a variable orifice. The system is installed between the air spring and the auxiliary air chamber, and is adjusted using a controller with a design based on the H? control algorithm. We carried out numerical simulations using a half railway vehicle model with a 4-element air suspension model, as well as performing excitation tests using a half carbody at a rolling stock test plant. The results show that the proposed system effectively reduces the power spectral density (PSD) of acceleration of the carbody floor. Additionally, little difference was observed between the vibration mitigation effectiveness of a reduced-order controller and that of the original one.

Sugahara, Yoshiki; Takigami, Tadao; Kazato, Akihito

188

On mathematical modelling of insect flight dynamics in the context of micro air vehicles  

Microsoft Academic Search

We discuss some aspects of mathematical modelling relevant to the dynamics of insect flight in the context of insect-like flapping-wing micro air vehicles (MAVs). MAVs are small flying vehicles developed to reconnotre in confined spaces. This requires power-efficient, highly-manoeuvrable, low-speed flight with stable hover. All of these attributes are present in insect flight and hence the focus on reproducing the

Rafa? ?bikowski; Salman A Ansari; Kevin Knowles

2006-01-01

189

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

Microsoft Academic Search

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

Sefer Kurnaz; Okyay Kaynak; Ekrem Konakoglu

2007-01-01

190

Study of long term options for electric vehicle air conditioning  

Microsoft Academic Search

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

J. Dieckmann; D. Mallory

1991-01-01

191

Air System Management for Fuel Cell Vehicle Applications  

Microsoft Academic Search

Master's Thesis Research and development of fuel cell systems for multiple applications has dramatically increased in the past few years. The vehicular application of the fuel cell system as the powertrain leads to a number of unique challenges, namely physical packaging within the vehicle, durability and operation under extreme environmental conditions, and demanding duty cycles that include high peak power

JOSHUA MICHAEL CUNNINGHAM

2001-01-01

192

Supply of electric vehicles via magnetically coupled air coils  

Microsoft Academic Search

The paper describes the contactless electrical energy transfer system (CEETS), by which electrical energy may be transmitted, without electrical connection or physical contact, through the large air gap. In this case energy is transmitted via coreless transformer. Coupling between the coils changes and depend on dimension of air gap. The efficiency of CEETS is mainly depended on the transmission frequency.

Slawomir Judek; Krzysztof Karwowski

2008-01-01

193

Distributed pheromone-based swarming control of unmanned air and ground vehicles for RSTA  

NASA Astrophysics Data System (ADS)

The use of unmanned vehicles in Reconnaissance, Surveillance, and Target Acquisition (RSTA) applications has received considerable attention recently. Cooperating land and air vehicles can support multiple sensor modalities providing pervasive and ubiquitous broad area sensor coverage. However coordination of multiple air and land vehicles serving different mission objectives in a dynamic and complex environment is a challenging problem. Swarm intelligence algorithms, inspired by the mechanisms used in natural systems to coordinate the activities of many entities provide a promising alternative to traditional command and control approaches. This paper describes recent advances in a fully distributed digital pheromone algorithm that has demonstrated its effectiveness in managing the complexity of swarming unmanned systems. The results of a recent demonstration at NASA's Wallops Island of multiple Aerosonde Unmanned Air Vehicles (UAVs) and Pioneer Unmanned Ground Vehicles (UGVs) cooperating in a coordinated RSTA application are discussed. The vehicles were autonomously controlled by the onboard digital pheromone responding to the needs of the automatic target recognition algorithms. UAVs and UGVs controlled by the same pheromone algorithm self-organized to perform total area surveillance, automatic target detection, sensor cueing, and automatic target recognition with no central processing or control and minimal operator input. Complete autonomy adds several safety and fault tolerance requirements which were integrated into the basic pheromone framework. The adaptive algorithms demonstrated the ability to handle some unplanned hardware failures during the demonstration without any human intervention. The paper describes lessons learned and the next steps for this promising technology.

Sauter, John A.; Mathews, Robert S.; Yinger, Andrew; Robinson, Joshua S.; Moody, John; Riddle, Stephanie

2008-05-01

194

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

NASA Astrophysics Data System (ADS)

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 life cycle analysis was conducted and compared to that of lead/acid and nickel-metal hydride vehicles. Only the aluminum/air vehicles can be projected to have a travel range comparable to that of internal combustion engine vehicles (ICE). From this analysis, an aluminum/air vehicle is a promising candidate compared to ICE vehicles in terms of travel range, purchase price, fuel cost, and life cycle cost. We have chosen two grades of Al alloys (Al alloy 1350, 99.5% and Al alloy 1199, 99.99%) in our study. Only Al 1199 was studied extensively using Na 2SnO3 as an electrolyte additive. We then varied concentration and temperature, and determined the effects on the parasitic (corrosion) current density and open circuit potential. We also determined cell performance and selectivity curves. To optimize the performance of the cell based on our experiments, the recommended operating conditions are: 3--4 N NaOH, about 55°C, and a current density of 150--300 mA/cm2. We have modeled the cell performance using the equations we developed. The model prediction of cell performance shows good agreement with experimental data. For better cell performance, our model studies suggest use of higher electrolyte flow rate, smaller cell gap, higher conductivity and lower parasitic current density. We have analyzed the secondary current density distributions in a two plane, parallel Al/air cell and a wedge-type Al/air cell. The activity of the cathode has a large effect on the local current density. With increases in the cell gap, the local current density increases, but the increase is not as significant as the increase in the current density away from the entrance. By extending the cathode below the anode, the high local current density can be reduced.

Yang, Shaohua

195

Development of the aluminum-air battery for electric vehicle applications  

Microsoft Academic Search

Current progress is reported concerning the development of hardware for the aluminum-air electric vehicle battery. The polarization curves of large-scale aluminum-air cells (0.1-m² anodes) have been replicated in rapidly-refuelable cells of subscale size (167-cm²) which were constructed for stacking into multicell modules. Solution-side current colllection by a structure which makes point- or line contacts at the aluminum\\/electrolyte interface is described.

J. F. Cooper; R. V. Homsy

1981-01-01

196

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

Microsoft Academic Search

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

Shaohua Yang; Harold Knickle

2002-01-01

197

Parameter analysis of a practical lithium- and sodium-air electric vehicle battery  

Microsoft Academic Search

For electric vehicles (EV) having a 500km range between charges, there is a need to develop smaller and lower-cost batteries. Lithium-air has the potential to deliver a step change in the specific energy of rechargeable lithium batteries. In order to develop a practical, safe, smaller and lower-cost lithium and sodium-air rechargeable EV battery it is necessary to eliminate the formation

E. Peled; D. Golodnitsky; H. Mazor; M. Goor; S. Avshalomov

2011-01-01

198

Discrete-Event Simulation Model for Evaluating Air Force Reusable Military Launch Vehicle Post-Landing Operations.  

National Technical Information Service (NTIS)

The purpose of this research was to develop a discrete-event computer simulation model of the post-landing vehicle recoveoperations to allow the Air Force Research Laboratory, Air Vehicles Directorate to evaluate design and process decisions and their imp...

M. Martindale

2006-01-01

199

77 FR 16988 - Protection of Stratospheric Ozone: Amendment to HFO-1234yf SNAP Rule for Motor Vehicle Air...  

Federal Register 2010, 2011, 2012, 2013

...proposes revising a use condition for the refrigerant HFO-1234yf in motor vehicle air conditioning...CAS Reg. No.] 754-12-1) as a refrigerant in new motor vehicle air conditioning...J2844 standard for connections with refrigerant containers. We are revising this...

2012-03-23

200

Challenges for micro-scale flapping-wing micro air vehicles  

NASA Astrophysics Data System (ADS)

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.

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

2012-05-01

201

Estimates of the cost and energy consumption of aluminum-air electric vehicles  

NASA Astrophysics Data System (ADS)

Economic costs and primary energy consumption are estimated for general purpose electric vehicles using aluminum-air propulsion batteries within the time frame of the 1990's (earliest possible date of introduction). For an aluminum-air fuel economy of 36 tonne/km/kg-Al (optimized low-gallium alloys), a total refueling cost of 5.6 cents/km (1979$) was estimated for a 1.27 tonne vehicle. This is equivalent to $2 to 3/gal for automobiles of the same weight with fuel economies of 13.5 to 19.3 tonne-km/liter. The total primary energy consumption was estimated to be 1.3 to 1.7 kWh/km (coal) for the electric vehicle, which corresponds roughly to the energy cost of the automobiles using liquid fuels synthesized from coal. The energy consumption is 30 to 70 percent greater than the reference automobile using petroleum-derived gasoline.

Cooper, J. F.

1980-11-01

202

Towards Intelligent Mission Profiles of Micro Air Vehicles: Multiscale Viterbi Classification  

Microsoft Academic Search

In this paper, we present a vision system for object recognition in aerial images, which enables broader mission profiles for Mi cro Air Vehicles (MAVs). The most important factors that inform our design choices are: real-time constraints, robustness to video noise, and complexity of object appearances. As such, we first propose the HSI color space and the Complex Wave let

Sinisa Todorovic; Michael C. Nechyba

2004-01-01

203

A vision system for intelligent mission profiles of micro air vehicles  

Microsoft Academic Search

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

Sinisa Todorovic; Michael C. Nechyba

2004-01-01

204

Computer Based Data Management System for Automating the Air Force Vehicle Master Plan.  

National Technical Information Service (NTIS)

The purpose of this thesis is to examine the appropriateness of using a PC-based database management system for a process used in the planning, acquisition and depot repair strategies of Air Force vehicles and to develop a computer based database manageme...

H. Garcia

1989-01-01

205

Sensor Testing System for Design of a Quad-Winged Micro Air Vehicle.  

National Technical Information Service (NTIS)

A sensor testing system for sensing, control, and modeling of a quad- winged Micro Air Vehicle (MAV) has been built this work. This system contains two important components. One is an Agilent AFM system for microscopic static force measurement and calibra...

H. Dong Y. Zhuang

2010-01-01

206

Pitching Motion Control of Underwater Traveling LSM Vehicle ME02 Using Controlled Air-Cored Electromagnet  

Microsoft Academic Search

When Marine Express starts to propel, an undesired pitching motion is established. In the attractive mode of operation, the propulsion and levitation forces produce additive torques and pitching motion becomes highly unstable. The current paper introduces enhanced control scheme for pitching motion of the underwater linear motor vehicle ME02 in attractive mode. Two air-cored electromagnets are utilized to produce damping

K. Yoshida; M. El-Nemr; Y. Yamashita

207

Modelling and PID controller design for a quadrotor unmanned air vehicle  

Microsoft Academic Search

this paper presents the modelling of a four rotor vertical take-off and landing (VTOL) unmanned air vehicle known as the quadrotor aircraft. The paper presents a new model design method for the flight control of an autonomous quad rotor .The paper describes the controller architecture for the quadrotor as well. The dynamic model of the quad-rotor, which is an under

Atheer L. Salih; M. Moghavvemi; Haider A. F. Mohamed; Khalaf Sallom Gaeid

2010-01-01

208

Evaluation of the Thorax of Manduca Sexta for Flapping Wing Micro Air Vehicle Applications.  

National Technical Information Service (NTIS)

The tobacco hornworm hawkmoth (Manduca sexta) provides an excellent model from which to gather knowledge pertaining to the development of a Flapping Wing Micro Air Vehicle (FWMAV). One of the major challenges in design of a FWMAV is the energy demanding n...

B. C. Cranston

2012-01-01

209

Laser Dot Projection Photogrammetry and Force Balance Measurement Techniques for Flapping Wing Micro Air Vehicles.  

National Technical Information Service (NTIS)

The purpose of this research was to develop testing methods capable of analyzing the performance of a miniature flapping-wing mechanism that can later be adapted to a flapping wing micro air vehicle (MAV). A previously designed and built flapping only mec...

D. H. Curtis

2008-01-01

210

Biomimetic Micro Air Vehicle Testing Development and Small Scale Flapping-Wing Analysis.  

National Technical Information Service (NTIS)

The purpose of this research was to develop testing methods capable of analyzing the performance of a miniature flapping-wing mechanism that can later be adapted for the development a biomimetic flapping-wing micro air vehicle (MAV). Three small scale fla...

C. E. Svanberg

2008-01-01

211

CRITERIA AND AIR TOXIC EMISSIONS FROM IN-USE, LOW EMISSION VEHICLES (LEVS)  

EPA Science Inventory

The U.S. Environmental Protection Agency implemented a program to identify tailpipe emissions of criteria and air toxic contaminants from in-use, light-duty Low Emission Vehicles (LEVs). EPA recruited twenty-five LEVs in 2002, and measured emissions on a chassis dynamometer usin...

212

Design of permanent magnet brushless motors with asymmetric air gap for electric vehicles  

Microsoft Academic Search

This paper proposes a cost-effective approach to design permanent magnet brushless dc motors for electric vehicles. The key is to shape the pole arc in such a way that the air gap length is at a maximum at the leading edge of each rotor pole arc and at a minimum at the trailing edge of the same pole arc, hence

K. T. Chau; Wei Cui; J. Z. Jiang; Zheng Wang

2006-01-01

213

Dynamic surface control for nonlinear hypersonic air vehicle using neural network  

Microsoft Academic Search

In this paper dynamic surface control (DSC) technique is combined with neural network based adaptive control design framework to design the longitudinal dynamics controller for a nonlinear generic hypersonic air vehicle (HSAV). Detailed stability analysis is carried out to prove the uniform ultimate boundedness of all the signals in the closed loop system. The effectiveness of the proposed strategy is

Waseem Aslam BUTT; Lin Yan; Amezquita S. KENDRICK

2010-01-01

214

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

Microsoft Academic Search

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

Dong Ming Ge; Xian Lin. Huang

2010-01-01

215

Virtual motion camouflage based phantom track generation through cooperative electronic combat air vehicles  

Microsoft Academic Search

As an example of complex cooperative missions, coherent phantom track generation through controlling multiple electronic combat air vehicles is currently an area of great interest to the defense agency for the purpose of deceiving a radar network. However, it has been a challenge to design the optimal or even feasible coherent trajectories for this type of problem due to the

Yunjun Xu; Gareth Basset

2010-01-01

216

A novel asymmetrical pitch system for a rotor micro air vehicle  

Microsoft Academic Search

Concerning to problems of the traditional machine pitch system for miniaturizing Micro Air Vehicles (MAVs), A novel asymmetrical pitch method is put forward in this paper. This novel method makes use of the deformation of an elasticity link to generate the blade pitch meeting the requirement of the MAV flight mode control. This new pitch mechanism has been verified by

Shaorong Xie; Jun Luo; Zhenbang Gong; Shanbo Hao

2007-01-01

217

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

Microsoft Academic Search

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

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

1999-01-01

218

Follow-up Study on Wireless Power Transmission for Unmanned Air Vehicles.  

National Technical Information Service (NTIS)

This thesis was a continuation in part of a NPS project relating to microwave wireless power transmission for micro air vehicles (MAVs). The concept of using microwaves for transferring power in free space has existed since the beginning of the 20th centu...

L. H. Toh

2007-01-01

219

Vision-based target motion estimation of multiple air vehicles using unscented information filter  

Microsoft Academic Search

This paper presents target motion estimation for multiple air vehicles. The motion of the airborne target is estimated by vision information from camera sensors fixed to the followers. Each camera sensors provides information of the target by three angles: an azimuth angle, an elevation angle, and a subtended angle. In the frame work of information filter, each follower estimates position,

Kwangyul Baek; Hyochoong Bang

2010-01-01

220

Vision-guided flight stability and control for micro air vehicles  

Microsoft Academic Search

Substantial progress has been made recently towards design- ing, building and test-flying remotely piloted Micro Air Vehicles (MAVs) and small UAVs. We seek to complement this progress in overcoming the aerodynamic obstacles to flight at very small scales with a vision-guided flight stability and autonomy system , based on a robust horizon detection algorithm. In this paper, we first motivate

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

2003-01-01

221

A regenerative zinc air fuel cell for industrial and specialty vehicles  

Microsoft Academic Search

Metallic Power has demonstrated a regenerative zinc\\/air fuel cell for applications in industrial and specialty vehicles. The fuel cell uses zinc pellets and atmospheric oxygen to generate electric current. The reaction product is zinc oxide, which is collected in a tank. In its present stage of development, the 36 V fuel cell will deliver approximately 6 kWh, with a maximum

S. Smedley

2000-01-01

222

Technologies for Reducing Air Pollution on the Motor Vehicle Sector.  

National Technical Information Service (NTIS)

Automobile traffic as a source of air pollution is compared with power plants, households, and industry. Some concepts for reducing pollutant emissions with car exhaust are presented, e.g. 1. shifting of the ignition point with lower peak temperatures of ...

Zander

1984-01-01

223

Issues in the design of fault tolerant vehicle management systems for next generation unstable air vehicles  

Microsoft Academic Search

The author describes design issues in fault-tolerant vehicle management systems (VMS) for next-generation high-performance aircraft. Unstable aircraft require a highly reliable fault-tolerant computer to perform dynamic compensation of effector surface controls. Next-generation system requirements for system availability and performance will extend the role of flight criticality beyond the flight data sensors and actuation control functions. Additional control systems requiring a

T. D. Gaska

1988-01-01

224

Seacoaster advanced marine vehicle. Final report  

SciTech Connect

The Seacoaster combines the high efficiencies of Surface Effect Ships (SES) with simple catamaran hull construction. It has blower pressurized air cushions that support some 80-90 percent of displacement and hence the high efficiencies. However, unlike the SES, there are no expensive and high maintenance flexible seals. Each catamaran sidehull has a simple recess molded or built into its underside. Powered blowers direct pressurized air into such recesses and thereby create lifting air cushions. There are no flexible seals of any kind and there is no air cushion between the sidehulls. Extensive towed model tests were conducted that showed the viability of the invention.

Burg, D.

1998-08-18

225

An Air-Launched Hypersonic Vehicle Performance Model  

Microsoft Academic Search

A new performance model was developed for hydrocarbon fuelled (Jet A) scramjet powered hypersonic systems. It was applied to air-launched hypersonic missile concepts that were boosted to a specified Mach number (3) and dynamic pressure (40-100 kPa) using a solid propellant rocket motor. After boost, a dual-mode airbreathing supersonic ramjet engine accelerates the missile concept along a constant dynamic pressure,

Con J. Doolan

2006-01-01

226

Design analysis of an aluminum-air battery for vehicle operations. Transportation systems research  

SciTech Connect

The objective of the study reported was to perform a detailed configuration analysis of an aluminum-air battery, evaluate various automobile propulsion systems utilizing the Al-air battery, and estimate the performance and cost of vehicles incorporating these propulsion systems. A preliminary engineering design is performed. A physical model and a cell-performance model of a conceptual mass-produced Al-air battery were constructed and work together to characterize the battery system. The physical battery model is based on a specific battery design concept and defines the mass and volume of a complete Al-air battery system. The cell-performance model simulates the electrical and electrochemical characteristics of the battery. The physical model and two versions of the cell-performance model - near-term and optimistic - were used in a vehicle-conversion analysis to evaluate three automotive propulsion systems - Al-air battery only, Al-air battery/secondary battery, and Al-air battery/flywheel. (LEW)

Behrin, E.; Wood, R.L.; Salisbury, J.D.; Whisler, D.J.; Hudson, C.L.

1983-03-18

227

Effect of Vehicle type on the Performance of Second Generation Air Bags for Child Occupants  

PubMed Central

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.

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

2003-01-01

228

Assessment of air quality in a commercial cattle transport vehicle in Swedish summer and winter conditions.  

PubMed

Transport by road can induce significant stress in cattle. Thermal stress is among the main stress producing factors during transport. The provision of ventilation in livestock transport vehicles is usually through openings along the sides of the vehicle. The incoming air will affect air quality inside by regulating temperature, relative humidity, gas levels and levels of other contaminants. The aim of the present investigation was to map out the air quality in a commercial cattle transport vehicle under various climatic conditions and with varying stocking densities and transport times. Distributions of air temperature, relative humidity and concentrations of ammonia, carbon dioxide, oxygen and methane have been determined during 35 experimental journeys. In average the mean temperature inside the compartment was about 3 degrees C and 6 degrees C higher than outside temperature in summer (+7.8(-)+24.0 degrees C) and winter (-24.3(-)+12.7 degrees C) conditions respectively. The temperature increment inside, as could be expected from theory, increased with reduced ventilation and increased animal density. Many stops to load new animals lowered the temperature increment and relative humidity in winter time. In summer more stops made the compartment temperature and relative humidity increase. The inside temperature distribution was less than about 3 degrees C during both summer and winter season. Average ammonia level varied between 3 and 6 ppm depending on stocking density and number of stops with a maximum value of 18 ppm. No detectable methane levels could be found inside the compartment at any time. PMID:12731108

Wikner, I; Gebresenbet, G; Nilsson, C

2003-03-01

229

Concentrations of air toxics in motor vehicle-dominated environments.  

PubMed

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

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

2011-02-01

230

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

PubMed

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

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

2010-11-24

231

Orbit-on-demand vehicle propelled by air-turborocket/ramjet engines  

NASA Astrophysics Data System (ADS)

A preliminary design study has been completed for a fully reusable, single-stage-to-orbit transatmospheric vehicle. The specified mission capability was to lift a 20,000 lb payload to low earth orbit. A ground accelerator-assisted horizontal take-off was chosen to increase operational flexibility. The multi-mode propulsion system included the use of air-turborocket, ramjet, scramjet and rocket engines. Weight and performance estimates were obtained for the vehicle. A computer package was developed to perform aerothermodynamic analyses of the propulsion modes throughout the flight environment from take-off to low earth orbit. Results are presented for a semi-optimized trajectory. The analysis indicates that a vehicle of this type has great potential for providing low cost, flexible access to space.

Hartung, L.; Karkow, J.; Ordway, W.; Pickett, D.; Muras, A.

1986-06-01

232

Predictive model for vehicle air exchange rates based on a large, representative sample.  

PubMed

The in-vehicle microenvironment is an important route of exposure to traffic-related pollutants, particularly ultrafine particles. However, significant particle losses can occur under conditions of low air exchange rate (AER) when windows are closed and air is recirculating. AERs are lower for newer vehicles and at lower speeds. Despite the importance of AER in affecting in-vehicle particle exposures, few studies have characterized AER and all have tested only a small number of cars. One reason for this is the difficulty in measuring AER with tracer gases such as SF(6), the most common method. We developed a simplified yet accurate method for determining AER using the occupants' own production of CO(2), a convenient compound to measure. By measuring initial CO(2) build-up rates and equilibrium values of CO(2) at fixed speeds, AER was calculated for 59 vehicles representative of California's fleet. AER measurements correlated and agreed well with the largest other study conducted (R(2) = 0.83). Multivariable models captured 70% of the variability in observed AER using only age, mileage, manufacturer, and speed. These results will be useful to exposure and epidemiological studies since all model variable values are easily obtainable through questionnaire. PMID:21428392

Fruin, Scott A; Hudda, Neelakshi; Sioutas, Constantinos; Delfino, Ralph J

2011-03-23

233

Weight and volume estimates for aluminum-air batteries designed for electric vehicle applications  

NASA Astrophysics Data System (ADS)

The weights and volumes of reactants, electrolyte, and hardware components are estimated for an aluminum-air battery designed for a 40-kW (peak), 70-kWh aluminum-air battery. Generalized equations are derived which express battery power and energy content as functions of total anode area, aluminum-anode weight, and discharge current density. Equations are also presented which express total battery weight and volume as linear combinations of the variables, anode area and anode weight. The sizing and placement of battery components within the engine compartment of typical five-passenger vehicles is briefly discussed.

Cooper, J. F.

1980-01-01

234

NEURAL NETS AND OPTIC FLOW FOR AUTONOMOUS MICRO-AIR-VEHICLE NAVIGATION  

Microsoft Academic Search

Reconnaissance, surveillance and target acquisition tasks in near-Earth environments like forests, caves, tunnels and build- ings is a grand challenge. Micro-air-vehicles are a future line of bird-sized flying assets designed to address such a challenge. Needed are light-weight and miniature sensor suites that can provide autonomous collision avoidance in complex environ- ments. Our demonstrations with optic flow microsensors have been

Paul Y. Oh; William E. Green; Geoffrey Barrows; DSC TOC

2004-01-01

235

Design of decimation filter for real-time signal processing of micro-air-vehicles  

Microsoft Academic Search

This paper reports a digital decimation filter chip for real-time signal processing of micro-air-vehicles (MAVs), which is composed of cascade integrator comb (CIC) filter, half-band filter and CIC compensation filter. To obtain low power, low hardware cost and efficient area, optimization was performed at behavioral level modeling and register transfer level (RTL) design. A mathematical framework was presented to perform

Ying-tao Ding; Shun-an Zhong; Jing Chen

2011-01-01

236

Robust and anti-windup control of air-breathing hypersonic cruise vehicle  

Microsoft Academic Search

This paper describes the design of robust and anti-windup controllers for an air-breathing hypersonic vehicle model. Firstly, a control algorithm is presented to design robust and anti-windup controllers for linear systems with modeling uncertainties and input saturation nonlinearities. Based on the characterization of modeling uncertainties and saturation nonlinearities via integral quadratic constraints (IQCs), the analysis and synthesis conditions are presented

Xian Lin Huang; Dong Ming Ge

2010-01-01

237

L1 adaptive controller for air-breathing hypersonic vehicle with flexible body dynamics  

Microsoft Academic Search

This paper presents a modified nonlinear longitudinal model for an air-breathing hypersonic vehicle and the design of an L1 adaptive controller for it. It is assumed that the mid-fuselage is a rigid-body, while the aft-fuselage is linearly elastic, and a rigid all-movable elevator is fixed at the end of the aft-fuselage. In the resulting mathematical model, the pitching moment depends

Yu Lei; Chengyu Cao; Eugene Cliff; Naira Hovakimyan; Andrew Kurdila; Kevin Wise

2009-01-01

238

Numerical prediction and wind tunnel experiment for a pitching unmanned combat air vehicle  

Microsoft Academic Search

The low-speed flowfield for a generic unmanned combat air vehicle (UCAV) is investigated both experimentally and numerically. A wind tunnel experiment was conducted with the Boeing 1301 UCAV at a variety of angles of attack up to 70 degrees, both statically and with various frequencies of pitch oscillation (0.5, 1.0, and 2.0 Hz). In addition, pitching was performed about three

Russell M. Cummings; Scott A. Morton; Stefan G. Siegel

2008-01-01

239

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

Microsoft Academic Search

In this paper, the decade of numerical and experimental investigations leading to the development of the authors’ unique flapping-wing\\u000a micro air vehicle is summarized. Early investigations included the study of boundary layer energization by means of a small\\u000a flapping foil embedded in a flat-plate boundary layer, the reduction of the recirculatory flow region behind a backward-facing\\u000a step by means of

Kevin D. Jones; Max F. Platzer

2009-01-01

240

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

Microsoft Academic Search

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

Jason L. Pereira

2008-01-01

241

Ant-based swarming with positionless micro air vehicles for communication relay  

Microsoft Academic Search

Swarming without positioning information is interesting in application-oriented systems because it alleviates the need for\\u000a sensors which are dependent on the environment, expensive in terms of energy, cost, size and weight, or unusable at useful\\u000a ranges for real-life scenarios. This principle is applied to the development of a swarm of micro air vehicles (SMAVs) for\\u000a the deployment of ad hoc

Sabine Hauert; Laurent Winkler; Jean-christophe Zufferey; Dario Floreano

2008-01-01

242

Optimal path planning for unmanned air vehicles with kinematic and tactical constraints  

Microsoft Academic Search

We consider a class of 2D optimal path-planning problems for unmanned air vehicles (UAVs) with kinematic and tactical constraints. The existence of an optimal path class satisfying the UAV kinematic constraints and vector calculus are exploited to reduce this class of optimal path-planning problems to a parameter optimization problem. Illustrative tactical constraints arising in target touring and obstacle avoidance problems

Guang Yang; Vikram Kapila

2002-01-01

243

A Rotary-wing Unmanned Air Vehicle for Aquatic Weed Surveillance and Management  

Microsoft Academic Search

This paper addresses the novel application of an autonomous rotary-wing unmanned air vehicle (RUAV) as a cost-effective tool\\u000a for the surveillance and management of aquatic weeds. A conservative estimate of the annual loss of agricultural revenue to\\u000a the Australian economy due to weeds is in the order of A$4 billion, hence the reason why weed control is of national significance.

Ali Haydar Gökto?an; Salah Sukkarieh; Mitch Bryson; Jeremy Randle; Todd Lupton; Calvin Hung

2010-01-01

244

Optimum Aeroelastic Design of Resonance Type Flapping Wing for Micro Air Vehicles  

NASA Astrophysics Data System (ADS)

The optimum aeroelastic design method for a resonance-type flapping wing for a Micro Air Vehicle (MAV) is presented. It uses Complex Method and 3D Navier-Stokes code to determine the optimum structural and aerodynamic parameters of a 2 DOF flapping wing system. The method is used to design a dragonfly-type MAV, and numerical simulation shows that the designed flapping wings can generate sufficient lift to sustain the weight and sufficient thrust to overcome the body drag.

Isogai, Koji; Kamisawa, Yuichi; Sato, Hiroyuki

245

Measurement and modelling of the y-direction apparent mass of sitting human body–cushioned seat system  

Microsoft Academic Search

Laboratory tests were conducted using 13 male subjects seated on a cushioned commercial vehicle driver's seat. The hands gripped a mock-up steering wheel and the subjects were in contact with the lumbar region of the backrest. The accelerations and forces in the y-direction were measured during random lateral whole-body vibration with a frequency range between 0.25 and 30Hz, vibration magnitudes

George Juraj Stein; Peter Múcka; Barbara Hinz; Ralph Blüthner

2009-01-01

246

Comparative biomechanical evaluation of different wheelchair seat cushions.  

PubMed

The aim of the present study was to perform a comparative biomechanical analysis of four antidecubitus wheelchair cushions. Thirty wheelchair users were considered divided into three groups: paraplegic subjects (with no cutaneous sensation), neurologic subjects (with intact cutaneous sensation), and elderly subjects. The biomechanical evaluation was performed using a piezoresistive sensor matrix system to quantify parameters referred to pressure distribution, seating surface and posture. Dedicated software was developed for the automatic elaboration of the raw data and the computation of the parameters of interest. Differences among cushion types and subject groups were analyzed. An analysis of time-transient behaviors was also performed. Results showed that no significant differences in pressure peak reduction were found among the four cushions. Moreover, no time-transient behavior was shown by any cushions. However, both the location of pressure peaks and posture were dependent on cushion types. Comparison of the three subject groups showed that elderly subjects had the highest mean pressure and the lowest contact surface, while paraplegics presented the highest pressure peaks. This procedure appears indicated for individualizing the prescription of a wheelchair cushion and even for customizing a cushion to induce a specific posture. PMID:10917263

Ferrarin, M; Andreoni, G; Pedotti, A

247

System 411L. Airborne Warning and Control System. System Study. Volume VII. System Substantiation - Air Vehicle Subsystems.  

National Technical Information Service (NTIS)

Contents: Air Vehicle Subsystem--Introduction, Secondary power (Secondary power subsystem selection, electrical power subsystem, hydraulic subsystem and auxiliary power unit), Airframe (Radome structural design, rotodome and support structural configurati...

1967-01-01

248

Motion planning and control for mothership-cable-drogue systems in aerial recovery of micro air vehicles  

Microsoft Academic Search

Aerial recovery of micro air vehicles (MAVs) presents a challenging problem in multi-vehicle dynamics and control. This paper presents a method for recovering 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. The differential flatness property of

Liang Sun; Randal W. Beard; Mark B. Colton

2010-01-01

249

Ambient particulate air pollution from vehicles promotes lipid peroxidation and inflammatory responses in rat lung.  

PubMed

Oxidative stress plays a major role in the pathogenesis of particle-dependent lung injury. Ambient particle levels from vehicles have not been previously shown to cause oxidative stress to the lungs. The present study was conducted to a) determine whether short-term exposure to ambient levels of particulate air pollution from vehicles elicits inflammatory responses and lipid peroxidation in rat lungs, and b) determine if intermittent short-term exposures (every 4 days) induce some degree of tolerance. Three-month-old male Wistar rats were exposed to ambient particulate matter (PM) from vehicles (N = 30) for 6 or 20 continuous hours, or for intermittent (5 h) periods during 20 h for 4 consecutive days or to filtered air (PM <10 microm; N = 30). Rats continuously breathing polluted air for 20 h (P-20) showed a significant increase in the total number of leukocytes in bronchoalveolar lavage compared to control (C-20: 2.61 x 105 +/- 0.51;P-20: 5.01 x 105 +/- 0.81; P < 0.05) and in lipid peroxidation ([MDA] nmol/mg protein: C-20: 0.148 +/- 0.01; P-20: 0.226 +/- 0.02; P < 0.05). Shorter exposure (6 h) and intermittent 5-h exposures over a period of 4 days did not cause significant changes in leukocytes. Lipid damage resulting from 20-h exposure to particulate air pollution did not cause a significant increase in lung water content. These data suggest oxidative stress as one of the mechanisms responsible for the acute adverse respiratory effects of particles, and suggest that short-term inhalation of ambient particulate air pollution from street with high automobile traffic represents a biological hazard. PMID:17713644

Pereira, C E L; Heck, T G; Saldiva, P H N; Rhoden, C R

2007-08-14

250

AirCRED : the rationale and structure of a tool for estimating air pollutant reduction credits for alternative fuel vehicles.  

SciTech Connect

Primarily to assist the U.S. Department of Energy's Clean Cities coalitions in estimating the net benefits of reducing air pollutant emissions gained by acquiring original equipment manufacture (OEM) alternativefuel vehicles (AFVs), Argonne National Laboratory has developed a graphical user interface-based benefit calculation model called AirCred. The application of this modeling tool has been extended to the estimation of state implementation plan credits for AFVs that may be claimed in nonattainment and maintenance regions for ozone and carbon monoxide. The tool also has been approved for and applied to the quantification of projected program benefits in applications for grant support to purchase OEM AFVs under the U.S. Department of Transportation's Congestion Mitigation and Air Quality Program. First, the model's founding principles and relatively simple mechanics are presented, accompanied by graphic displays of data input screens and comparative results for various vehicular categories. Current and future plans are cited for enhancement of the tool, including its respecification for consistency with MOBILE6 and for air planning in the yet-to-be-designated nonattainment areas for ambient particulate matter of 2.5 {mu}m and smaller. Then some issues and controversies about how and where AirCred should be applied are chronicled. Finally, some example applications are presented to illustrate the residual benefits of AFVs over time relative to their conventionally fueled counterparts of the same (recent) model year. Results indicate that AFVs of certain categories will remain viable and attractive candidates for reducing air emissions in ozone and carbon monoxide air quality control regions well into the future.

Saricks, C. L.; Energy Systems

2002-01-01

251

Electric vehicles  

Microsoft Academic Search

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,

M. J. Riezenman

1992-01-01

252

Design of permanent magnet brushless motors with asymmetric air gap for electric vehicles  

NASA Astrophysics Data System (ADS)

This paper proposes a cost-effective approach to design permanent magnet brushless dc motors for electric vehicles. The key is to shape the pole arc in such a way that the air gap length is at a maximum at the leading edge of each rotor pole arc and at a minimum at the trailing edge of the same pole arc, hence resulting in an asymmetric air gap. Thus, for a specified rotational direction, the distortion of air gap flux density and hence the torque ripple can be significantly suppressed. Also, with the use of advanced conduction angle control, the motor can achieve a wide speed range. The proposed motor drive is designed and implemented for a low-voltage battery-powered electric motorcycle.

Chau, K. T.; Cui, Wei; Jiang, J. Z.; Wang, Zheng

2006-04-01

253

21 CFR 874.1100 - Earphone cushion for audiometric testing.  

Code of Federal Regulations, 2013 CFR

...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....

2013-04-01

254

Evaluation of Expanded Bead Polyethylene Foam Cushioning For Packaging.  

National Technical Information Service (NTIS)

Expanded Bead Molded Polyethylene Foam Cushioning Material was evaluated for its static and dynamic characteristics. It was determined that the material meets the compression set and compressive strength requirements of Type I material of PPP-C-1752A, 'Cu...

R. V. Brown

1979-01-01

255

Prospects for utilization of air liquefaction and enrichment system (ALES) propulsion in fully reusable launch vehicles  

NASA Astrophysics Data System (ADS)

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 LH2 fuel. The turborocket employs a modified liquid air cycle to supply the oxidizer. The rocket uses 90 percent pure LOX that is collected from the atmosphere, separated, and stored during operation of the turborocket from about Mach 2 to Mach 5 or 6. The takeoff weight and the thrust required at takeoff are markedly reduced by collecting the rocket oxidizer in-flight. The paper shows an approach and the corresponding technology needs for using ALES propulsion in a 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, is critical to meet the structure weight objective for SSTO. Configurations that utilize 'waverider' aerodynamics show great promise to reduce the vehicle weight.

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

1993-06-01

256

Utilizing adaptive wing technology in the control of a micro air vehicle  

NASA Astrophysics Data System (ADS)

Evolution of the design of micro air vehicles (MAVs) towards miniaturization has been severely constrained by the size and mass of the electronic components needed to control the vehicles. Recent research, experimentation, and development in the area of smart materials have led to the possibility of embedding control actuators, fabricated from smart materials, in the wing of the vehicle, reducing both the size and mass of these components. Further advantages can be realized by developing adaptive wing structures. Small size and mass, and low airspeeds, can lead to considerable buffeting during flight, and may result in a loss of flight control. In order to counter these effects, we are developing a thin, variable-cambered airfoil design with actuators embedded within the wing. In addition to reducing the mass and size of the vehicle or, conversely, increasing its available payload, an important benefit from the adaptive wing concept is the possibility of in-flight modification of the flight envelope. Reduced airspeeds, which are crucial during loiter, can be realized by an in-flight increase in wing camber. Conversely, decreases in camber provide for an airframe best suited for rapid ingress/egress and extension of the mission range.

Null, William R.; Wagner, Matthew G.; Shkarayev, Sergey V.; Jouse, Wayne C.; Brock, Keith M.

2002-07-01

257

Dynamic modelling of servo pneumatic actuators with cushioning  

Microsoft Academic Search

Precise modelling of servo-pneumatic actuation plants continues to remain a major challenge. In this work, the complete mathematical\\u000a model of a double-acting pneumatic cylinder with cushioning sections at both ends of the piston stroke has been developed.\\u000a The proposed model considers the entire stroke of the piston, including cushioning sections as these sections affect the positioning\\u000a accuracy of the piston.

Farid Najafi; Morteza Fathi; Mozafar Saadat

2009-01-01

258

Effect of Air Bags and Restraining Devices on the Pattern of Facial Fractures in Motor Vehicle Crashes  

Microsoft Academic Search

Results: Use of seat belts alone was more effective in de- creasing the chance of facial fractures in this population (from 17% to 8%) compared with the use of air bags alone (17% to 11%). The use of seat belts and air bags together decreasedtheincidenceoffacialfracturesfrom17%to5%. Conclusions: Use of restraining devices in vehicles sig- nificantly reduces the chance of incurring facial

Payman Simoni; Robert Ostendorf; Artemus J. Cox III

2003-01-01

259

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...

260

An experimental study of a bio-inspired corrugated airfoil for micro air vehicle applications  

Microsoft Academic Search

An experimental study was conducted to investigate the aerodynamic characteristics of a bio-inspired corrugated airfoil compared\\u000a with a smooth-surfaced airfoil and a flat plate at the chord Reynolds number of Re\\u000a C\\u000a  = 58,000–125,000 to explore the potential applications of such bio-inspired corrugated airfoils for micro air vehicle designs.\\u000a In addition to measuring the aerodynamic lift and drag forces acting on

Jeffery T. Murphy; Hui Hu

2010-01-01

261

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

NASA Astrophysics Data System (ADS)

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.

Jones, Kevin D.; Platzer, Max F.

262

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

NASA Astrophysics Data System (ADS)

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.

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

2013-12-01

263

The use of compressed natural gas (CNG) in motor vehicles and its effect on employment and air quality  

Microsoft Academic Search

This study measures industrial output, employment and air pollution effects through the use of CNG in motor vehicles by utilizing the Pollution-Related Multiregional Household-Interactive Variable Input-Output (PHVIO) model. The impact analyses are conducted with three consecutive year scenarios of different level of CNG conversion of motor fleet vehicles for the target year, 1991, 1992, and 1993. The use of CNG

Chung J. Liew; Chong K. Liew

1995-01-01

264

Field test of the Electric FuelTM zinc-air refuelable battery system for electric vehicles  

Microsoft Academic Search

The Electric Fuel Limited (EFL) zinc-air refuelable battery system will be tested over the next two years in a number of electric vehicle demonstration projects, the largest of which is an $18-million, 64-vehicle, two-year test sponsored chiefly by Deutsche Post AG (the German Post Corporation). The German field test is the largest-ever EV fleet test of a single advanced-battery technology.

Jonathan R. Goldstein; Binyamin Koretz; Yehuda Harats

1996-01-01

265

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

DOEpatents

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.

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

2001-01-01

266

Vibration Effects Examination of Cushions Used on Tractor Driving Seat  

NASA Astrophysics Data System (ADS)

Vibration effect of driver’s seat of agricultural tractor which works in land condition has been researched. In this research, three dif- ferent cushions on driver’s seat have been used. These are wool, sponge and cotton. Pad acceleration receiver is put on seat. Moreover, HVM100 tool has been used to record data. Data has been converted to graphs in BLAZE software. Statistical methods have been used in examining the graphs. In vibration isolation, ordering has been achieved as wool, cotton and sponge and without a cushion, respectively. Wool cushion has the best isolation. It is seen that data obtained from test results is appropri- ate according to ISO 2631 standards and scientific researches.

Marul, Musa; Karabulut, Abdurrahman

2012-12-01

267

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

NASA Astrophysics Data System (ADS)

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).

Hrishikeshavan, Vikram

268

Development of a cushion to prevent ischial pressure sores.  

PubMed Central

A study was carried out jointly by nursing staff and technologists in an attempt to develop a cushion based on scientific principles and measurement that might prevent pressure sores. At each stage in the development clinical trials were carried out, and using the results of these together with the opinions of medical staff and patients who used the cushion the design was suitably modified. Over four years a seat was evolved that was simple to construct and fulfilled the clinical requirements for a wide range of patients while providing maximum relief of high-pressure points. The design was subsequently taken up commercially. Images Fig 3

Bowker, P; Davidson, L M

1979-01-01

269

A Method to Control the Cushion Pressure of Oscillating SES  

NASA Astrophysics Data System (ADS)

A method is proposed to control the variation of cushion pressure of SES oscillating vertically. The peripheral nozzle is attached along the periphery and swings changing the discharge angle. The angle varies in accordance with the motion of the craft. A method is proposed to analyze the mechanism of this setup. The result is compared with experiments to show the agreement of the two results. It has been shown both theoretically and experimentally that the variation of the cushion pressure is effectively controlled adjusting the amplitude and the phase of the swinging motion of the nozzle.

Senba, Hiromitsu; Matsuo, Hideo; Takahashi, Hidehiko; Yoshimoto, Shintarou; Matsuo, Kensuke; Kanazawa, Koji; Hiroe, Tetsuyuki; Fujiwara, Kazuhito

270

In-flight oxygen collection for a two-stage air-launch vehicle: integration of vehicle and separation cycle design  

NASA Astrophysics Data System (ADS)

In-flight oxygen collection is a very promising technique to reduce the launch costs and improve the payload capabilities of two-stage-to-orbit semireusable launchers. Using liquid hydrogen the incoming air is deeply cooled and enriched in oxygen during the cruise phase of the first stage. The liquified enriched air is stored in the second stage which is then launched into orbit. This paper gives the result of a conceptual design of a two-stage-to-orbit air launched space vehicle. The mass, aerodynamic, and propulsive characteristics of the first stage are determined and an assessment of the influence of the collection plant performance on the subsonic first stage is made. The results for a centrifugally enhanced destillation unit are given together with the plant cycle arrangement. Integration options for the plant into the first stage are proposed and a short description of the air separation test unit and its test bench is also given.

Verstraete, D.; Bizzarri, D.; Hendrick, P.

2009-09-01

271

Estimation of road vehicle exhaust emissions from 1992 to 2010 and comparison with air quality measurements in Genoa, Italy  

NASA Astrophysics Data System (ADS)

An investigation into road transport exhaust emissions in the Genoa urban area was performed by comparing the quantities of carbon monoxide (CO), nitrogen oxides (NO x), nitrogen dioxide (NO 2) and particulate matter (PM) emitted by different vehicle categories with air quality measurements referred to the same pollutants. Exhaust emissions were evaluated by applying the PROGRESS (computer PROGramme for Road vehicle EmiSSions evaluation) code, developed by the Internal Combustion Engines Group of the University of Genoa, to eight different years (from 1992 to 2010), considering spark ignition and Diesel passenger cars and light duty vehicles, heavy duty vehicles and buses, motorcycles and mopeds. Changes in terms of vehicles number, mileage and total emissions are presented together with relative distributions among the various vehicle categories. By comparing 1992 and 2010 data, calculated trends show a 7% increase in the number of vehicles, with total mileage growing at a faster rate (approx. 22%); total emissions decrease considerably, by approximately 50% for NO x and PM, 70% for HC and 80% for CO, due to improvements in engines and fuels forced by the stricter European legislation and the fleet renewal, while primary NO 2 emission will be very close to 1992 level, after a decrease of about 18% in 2000. Air quality was analysed by selecting traffic and background measuring stations from the monitoring network managed by the Environmental Department of the Province of Genoa: average annual concentrations of considered pollutants from 1994 to 2007 were calculated in order to obtain the relative historical trends and compare them with European public health limits and with road vehicle emissions. Though an important reduction in pollutant concentrations has been achieved as a consequence of cleaner vehicles, some difficulties in complying with present and/or future NO 2 and PM 10 limits are also apparent, thus requiring suitable measures to be taken by the local authorities.

Zamboni, Giorgio; Capobianco, Massimo; Daminelli, Enrico

272

Suppression of the Variation of Cushion Pressure for SES Using Vertically Moving Nozzles  

Microsoft Academic Search

In this paper the variation of cushion pressure is investigated theoretically to achieve comfortable riding of SES. A simpler and practical control method is proposed to control cushion pressure changes arising from pumping phenomenon that appears in SES cruising over the waves. Cushion pressure is controlled by varying the discharge height of the vertical nozzle. In this method the nozzle

Koji Kanazawa; Kensuke Matsuo; Hideo Matsuo

2009-01-01

273

Suppression of Variation in Cushion Pressure for SES Using Vertically Moving Nozzles  

Microsoft Academic Search

In this paper, variation in cushion pressure is investigated theoretically to achieve SES ride comfort. A simple and practical control method is proposed to control cushion pressure changes caused by pumping that appears in SES cruising over waves. Cushion pressure is controlled by varying the discharge height of the vertical nozzle. In this method, the nozzle height (hover height) is

Koji Kanazawa; Kensuke Matsuo; Hideo Matsuo

2010-01-01

274

Physical Properties of Two Biological Cushioning Materials from Wheat and Corn Starches  

Microsoft Academic Search

Cereal Chem. 72(1):38-41 Physical properties of two biological cushioning materials made from dates were significantly higher than those of the wheat starch extrudates. wheat and corn starch extrudates were compared with those of commercial Both biological cushioning materials showed similar water absorption plastic foam cushioning material. Characteristics measured included isotherms at three temperatures when the equilibrium moisture contents dimensions, bulk

W. WANG; R. A. FLORES; C. T. HUANG

275

77 FR 73459 - California State Motor Vehicle Pollution Control Standards; Notice of Waiver of Clean Air Act...  

Federal Register 2010, 2011, 2012, 2013

EPA has granted the California Air Resources Board (CARB) its request to confirm that its amendments to California's heavy-duty vehicle and engine on-board diagnostic (HD OBD) requirements that relax the standards for 2010-2012 model years (MYs) are within the scope of a previous waiver of preemption of the Clean Air Act (Act). The amendments to the HD OBD requirements for MY 2013 and later are......

2012-12-10

276

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

SciTech Connect

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.

NONE

1996-05-01

277

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

PubMed

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

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

2011-06-16

278

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

PubMed

MAVs (micro air vehicles) with a maximal dimension of 15 cm and nominal flight speeds of around 10 m s?¹, operate in a Reynolds number regime of 10? or lower, in which most natural flyers including insects, bats and birds fly. Furthermore, due to their light weight and low flight speed, the MAVs' flight characteristics are substantially affected by environmental factors such as wind gust. Like natural flyers, the wing structures of MAVs are often flexible and tend to deform during flight. Consequently, the aero/fluid and structural dynamics of these flyers are closely linked to each other, making the entire flight vehicle difficult to analyze. We have recently developed a hummingbird-inspired, flapping flexible wing MAV with a weight of 2.4-3.0 g and a wingspan of 10-12 cm. In this study, we carry out an integrated study of the flexible wing aerodynamics of this flapping MAV by combining an in-house computational fluid dynamic (CFD) method and wind tunnel experiments. A CFD model that has a realistic wing planform and can mimic realistic flexible wing kinematics is established, which provides a quantitative prediction of unsteady aerodynamics of the four-winged MAV in terms of vortex and wake structures and their relationship with aerodynamic force generation. Wind tunnel experiments further confirm the effectiveness of the clap and fling mechanism employed in this bio-inspired MAV as well as the importance of the wing flexibility in designing small flapping-wing MAVs. PMID:22126793

Nakata, T; Liu, H; Tanaka, Y; Nishihashi, N; Wang, X; Sato, A

2011-11-29

279

A refuelable zinc/air battery for fleet electric vehicle propulsion  

SciTech Connect

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.

Cooper, J.F.; Fleming, D.; Hargrove, D.; Koopman, R.; Peterman, K.

1995-04-20

280

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

NASA Astrophysics Data System (ADS)

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.

Rudd, E. J.; Lott, S.

1990-12-01

281

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

SciTech Connect

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--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.

Rudd, E.J. (ELTECH Systems Corp., Fairport Harbor, OH (United States). Research and Development Center); Lott, S. (Sandia National Labs., Albuquerque, NM (United States))

1990-12-01

282

65 FR 35430 - Control of Air Pollution From New Motor Vehicles: Proposed Heavy-Duty Engine and Vehicle...  

Federal Register 2010, 2011, 2012, 2013

...Air Pollutants to the Great Waters-Second Report to Congress...Air Pollutants to the Great Waters will be forthcoming the...alter growth patterns and change the balance of species...occurred in some areas of the...

2000-06-02

283

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

NASA Astrophysics Data System (ADS)

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.

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

2011-04-01

284

Highly efficient brushless motor design for an air-conditioner of the next generation 42 V vehicle  

Microsoft Academic Search

In the past few years, worldwide awareness of environmental problems has grown dramatically. The idling stop and 42 V battery system has attracted large attention for next generation vehicle. In order to adapt to idling stop, air-conditioning compressors are required to be changed to electric-motor driven from gasoline engine driven. This paper discusses the optimum design of a high speed

Hiroshi Murakami; Hisakazu Kataoka; Yukio Honda; Shigeo Morimoto; Yoji Takeda

2001-01-01

285

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

Microsoft Academic Search

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

Liang Sun; Randal W. Beard

2011-01-01

286

Measurement of Air Traffic Control Situational Awareness Enhancement Through Radar Support Toward Operating Envelope Expansion of an Unmanned Aerial Vehicle  

Microsoft Academic Search

Current airspace restrictions in Kabul limit the potential capability of the tactical unmanned air vehicle (TUAV) within the area of operations of the Kabul multinational brigade. An experiment was conducted using the OneSAF Testbed Baseline and a range of virtual simulations to examine the impact of five different radar options and three different information displays on the level of airspace

James S. Denford; John A. Steele; Roger L. Roy; Eugenia Kalantzis

2004-01-01

287

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

Microsoft Academic Search

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

Geoffrey L. Barrows; C. Neely

2000-01-01

288

Aerodynamics of low aspect ratio wings at low Reynolds numbers with applications to micro air vehicle design  

Microsoft Academic Search

The recent interest in the development of small UAVs and micro air vehicles has revealed a need for a more thorough understanding of the aerodynamics of small airplanes flying at low speeds. In response to this need, the present work presents a study of the lift, drag, and pitching moment characteristics of wings of low aspect ratio operating at low

Gabriel Eduardo Torres

2002-01-01

289

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

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

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

1999-01-01

290

Comparative biomechanical evaluation of different wheelchair seat cushions  

Microsoft Academic Search

The aim of the present study was to perform a com- parative biomechanical analysis of four antidecubitus wheel- chair cushions . Thirty wheelchair users were considered divided into three groups : paraplegic subjects (with no cuta- neous sensation), neurologic subjects (with intact cutaneous sensation), and elderly subjects. The biomechanical evaluation was performed using a piezoresistive sensor matrix system to quantify

Veterans Affairs

291

21 CFR 890.3175 - Flotation cushion.  

Code of Federal Regulations, 2013 CFR

...with water, air, gel, mud, or any other substance allowing a flotation media, used on a seat to lessen the likelihood of skin ulcers. (b) Classification. Class I (general controls). The device is exempt from the premarket notification...

2013-04-01

292

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

NASA Astrophysics Data System (ADS)

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.

Zhang, Yibang; Chen, Yanyan; Jin, Gang

2011-09-01

293

Moss cushions facilitate water and nutrient supply for plant species on bare limestone pavements.  

PubMed

Dense moss cushions of different size are distributed across the bare limestone pavements on Øland, SE Sweden. Increasing cushion size is predicted to physically protect and improve performance and colonization by vascular plants. Therefore, we tested water balance, phosphorus supply, and species richness, and evaluated duration of plant activity during desiccation as a function of ground area, for a large collection of moss cushions. We found that lower evaporation and higher water storage contributed equally to extending the desiccation period with increasing cushion size. Evaporation rates declined by the -0.36 power of cushion diameter, and were not significantly different from -0.50 for the square root function previously predicted for the increasing thickness of the boundary layer, with greater linear dimensions for smooth flat objects at low wind velocities. Size dependence vanished under stagnant conditions. One moss species was added to the species pool for every nine-fold increase in cushion area. Vascular plants were absent from the smallest cushions, whereas one or two species, on average, appeared in 375- and 8,500-cm(2) cushions with water available for 6 and 10 days during desiccation. Phosphorus concentrations increased stepwise and four-fold from detritus to surface mosses and to vascular plants, and all three pools increased with cushion size. We conclude that cushion mosses and cushion size play a critical role in this resource-limited limestone environment by offering an oasis of improved water and nutrient supply to colonization and growth of plants. PMID:22481304

Sand-Jensen, Kaj; Hammer, Kathrine Jul

2012-04-06

294

Exposure of Paris taxi drivers to automobile air pollutants within their vehicles  

PubMed Central

OBJECTIVES—To study the exposure of Parisian taxi drivers to automobile air pollutants during their professional activity.?METHODS—A cross sectional study was carried out from 27 January to 27 March 1997, with measurements performed in the vehicles of 29 randomly selected drivers. Carbon monoxide (CO) content was measured over an 8 hour period by a CO portable monitor. The fine suspended particles were measured according to the black smoke index (BS), with a flow controlled portable pump provided with a cellulose filter. The nitrogen oxides, NO and NO2 were measured with a passive sampler.?RESULTS—These drivers are exposed during their professional activity to relatively high concentrations of pollutants (mean, median (SD) 3.8, 2 (1.7) ppm for CO, 168, 164 (53) µg/m3 for BS, 625, 598 (224) µg/m3 for NO, and 139, 131 (43) µg/m3 for NO2.) For CO the concentrations were clearly lower than the threshold values recommended by the World Health Organisation. The situation is less satisfactory for the other pollutants, especially for the BS index. All concentrations of pollutants recorded were noticeably higher than concentrations in air recorded by the ambient Parisian air monitoring network and were close to, or slightly exceeded, the concentrations measured at the fixed stations close to automobile traffic. Pollutant concentrations were also influenced greatly by weather conditions.?CONCLUSION—This first French study conducted in taxi drivers shows that they are highly exposed to automobile pollutants. The results would justify a medical follow up of this occupational group.???Keywords: taxi drivers; exposure assessment

Zagury, E.; Le Moullec, Y.; Momas, I.

2000-01-01

295

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

NASA Astrophysics Data System (ADS)

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.

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

2011-05-01

296

Micro-electro-mechanical flapping wing technology for micro air vehicles  

NASA Astrophysics Data System (ADS)

Army combat operations have placed a high premium on reconnaissance missions for Unmanned Aerial Vehicles (UAVs) and Micro Air Vehicles (MAVs) (less than 15 cm in dimension and less than 20 g in mass). One approach for accomplishing this mission is to develop a biologically inspired flapping wing insect that can maneuver into confined areas and possess hovering capabilities. Analysis of insect flight indicates that in addition to the bending excitation (flapping), simultaneous excitation of the twisting degree-of-freedom (pitching) is required to manipulate the control surface adequately. Traditionally, bimorph piezoelectric PZT (Pb(Zr0.55Ti0.45)O3) actuators have been used in many applications to excite the bending degree-of-freedom. In laminated or layered structures, bend-twist coupling is governed by the existence of at least one anisotropic layer not aligned with the primary plate axes. By adding a layer of off-axis PZT segments to a PZT bimorph actuator, thereby producing a layered structure to be referred to as a functionally- modified bimorph, bend-twist coupling may be introduced to the flexural response of the layered PZT. Furthermore, by selectively charging off-axis layers in specific combinations with the bimorph, the response of the functionally-modified bimorph may be tailored yielding a biaxial actuator to actively control the flapping wing response. The present study presents an experimental investigation of both traditional bimorph and functionally-modified PZT bimorph designs intended for active bend-twist actuation of cm-scale flapping wing devices.

Hall, Asha J.; Riddick, Jaret C.

2012-03-01

297

Proceedings of the RAND Project AIR FORCE Workshop on Transatmospheric Vehicles.  

National Technical Information Service (NTIS)

Transatmospheric vehicles (TAVs) are envisioned as a new type of reusable launch vehicle that could insert payloads into low earth orbit or deliver them to distant targets within minutes. Such a vehicle may be able to carry out several types of military, ...

D. Gonzalez M. Eisman C. Shipbaugh T. Bonds A. TuanLe

1997-01-01

298

Multidisciplinary Design of Air-launched Satellite Launch Vehicle Using Particle Swarm Optimization  

Microsoft Academic Search

Launch vehicle design is a complex, multidisciplinary engineering activity that requires making difficult compromises to achieve a balance among competing objectives for the vehicle, including safety, reliability, performance, operability, and cost. Significant work has been done in recent years to advance the design, analysis and optimization of launch vehicles. In the present research effort we propose the application of Particle

Amer Farhan Rafique; He LinShu; Qasim Zeeshan; Ali Kamran

299

Design and performance of an insect-inspired nano air vehicle  

NASA Astrophysics Data System (ADS)

This work reports the structural design, actuation and performance of an insect-inspired nano air vehicle. For this purpose, an original design concept of resonant wings using indirect actuation and concise transmission to allow large and symmetrical bending angles, passive wing torsion and to minimize energy expenditure is presented. A simplified analytical model and a numerical approach for the transmission between the actuator and the wings are then proposed to validate the design. The all-polymer prototypes were obtained using micromachining SU-8 photoresist technology. An electromagnetic actuator was added to control the vibrating amplitudes and create passive wing torsion. The actuator was optimized to make it more effective whilst at the same time minimizing its mass. Prototypes with a global wingspan of 3.5 cm and a mass of 22 mg due to the structure and actuator are presented. Bending amplitudes of the wings up to 60° were measured with these prototypes. The resonant frequency of the wings varied according to the design and mass. It was demonstrated that it is possible to obtain, without an important driving mechanism a very promising kinematics.

Bontemps, A.; Vanneste, T.; Paquet, J.-B.; Dietsch, T.; Grondel, S.; Cattan, E.

2013-01-01

300

Relationship Between Vehicle Count and Particulate Air Pollution in Amman, Jordan.  

PubMed

The main objective of this cross-sectional comparative study is to observe the relationship between traffic-related air pollutants, particularly particulate matter (PM) of total suspended particulate (TSP) and PM of size 10 µm (PM10), and vehicle traffic in Amman, Jordan. Two study areas were chosen randomly as a high-polluted area (HPA) and low-polluted area (LPA). The findings indicate that TSP and PM10 were still significantly correlated with traffic count even after controlling for confounding factors (temperature, relative humidity, and wind speed): TSP, r = 0.726, P < .001; PM10, r = 0.719, P < .001). There was a significant positive relationship between traffic count and PM level: TSP, P < .001; PM10, P < .001. Moreover, there was a significant negative relationship between temperature and PM10 level (P = .018). Traffic volume contributed greatly to high concentrations of TSP and PM10 in areas with high traffic count, in addition to the effect of temperature. PMID:22899706

Alnawaiseh, Nedal Awad; Hashim, Jamal Hisham; Md Isa, Zaleha

2012-08-16

301

An experimental study of a bio-inspired corrugated airfoil for micro air vehicle applications  

NASA Astrophysics Data System (ADS)

An experimental study was conducted to investigate the aerodynamic characteristics of a bio-inspired corrugated airfoil compared with a smooth-surfaced airfoil and a flat plate at the chord Reynolds number of Re C = 58,000-125,000 to explore the potential applications of such bio-inspired corrugated airfoils for micro air vehicle designs. In addition to measuring the aerodynamic lift and drag forces acting on the tested airfoils, a digital particle image velocimetry system was used to conduct detailed flowfield measurements to quantify the transient behavior of vortex and turbulent flow structures around the airfoils. The measurement result revealed clearly that the corrugated airfoil has better performance over the smooth-surfaced airfoil and the flat plate in providing higher lift and preventing large-scale flow separation and airfoil stall at low Reynolds numbers (Re C < 100,000). While aerodynamic performance of the smooth-surfaced airfoil and the flat plate would vary considerably with the changing of the chord Reynolds numbers, the aerodynamic performance of the corrugated airfoil was found to be almost insensitive to the Reynolds numbers. The detailed flow field measurements were correlated with the aerodynamic force measurement data to elucidate underlying physics to improve our understanding about how and why the corrugation feature found in dragonfly wings holds aerodynamic advantages for low Reynolds number flight applications.

Murphy, Jeffery T.; Hu, Hui

2010-08-01

302

Structural studies of polymer-cushioned lipid bilayers.  

PubMed Central

The structure of softly supported polymer-cushioned lipid bilayers, prepared in two different ways at the quartz-solution interface, were determined using neutron reflectometry. The polymer cushion consisted of a thin layer of branched, cationic polyethyleneimine (PEI), and the bilayers were formed by adsorption of small unilamellar dimyristoylphosphatidylcholine (DMPC) vesicles. When vesicles were first allowed to adsorb to a bare quartz substrate, an almost perfect bilayer formed. When the polymer was then added to the aqueous solution, it appeared to diffuse beneath this bilayer, effectively lifting it from the substrate. In contrast, if the polymer layer is adsorbed first to the bare quartz substrate followed by addition of vesicles to the solution, there is very little interaction of the vesicles with the polymer layer, and the result is a complex structure most likely consisting of patchy multilayers or adsorbed vesicles.

Majewski, J; Wong, J Y; Park, C K; Seitz, M; Israelachvili, J N; Smith, G S

1998-01-01

303

The Australian Air Quality Forecasting System: the use of green scenarios of motor vehicle usage as an educational tool.  

PubMed

The Australian Air Quality Forecasting System (AAQFS) is one of several newly emerging, high-resolution, numerical air quality forecasting systems. The system is briefly described. A public education application of the air quality impact of motor vehicle usage is explored by computing the concentration and dosage of particulate matter less than 10 microm in aerodynamic diameter (PM10) for a commuter traveling to work between Geelong and Melbourne, Victoria, Australia, under "business-as-usual" and "green" scenarios. This application could be routinely incorporated into systems like AAQFS. Two methodologies for calculating the dosage are described: one for operational use and one for more detailed applications. The Clean Air Research Programme-Personal Exposure Study in Melbourne provides support for this operational methodology. The more detailed methodology is illustrated using a system for predicting concentrations due to near-road emissions of PM10 and applied in Sydney. PMID:18672710

Cope, Martin; Hess, Dale; Lee, Sunhee; Tory, Kevin; Burgers, Manuela; Lilley, Bill

2008-07-01

304

Interface shear and pressure characteristics of wheelchair seat cushions.  

PubMed

Pressure ulcer incidence rates have remained constant despite advances in support surface technology. Interface shear stress is recognized as a risk factor for pressure ulcer development and is the focus of many shear reduction technologies incorporated into wheelchair cushions; however, shear reduction has not been quantified in the literature. We evaluated 21 commercial wheelchair seat cushions using a new methodology developed to quantify interface shear stress, interface pressure, and horizontal stiffness. Interface shear stress increased significantly with applied horizontal indenter displacement, while no significant difference was found for interface pressure. Material of construction resulted in significant differences in interface shear stress, interface pressure, and horizontal stiffness. This study shows that the existing International Organization for Standardization (ISO) 16840-2 horizontal stiffness measure provides similar information to the new horizontal stiffness measure. The lack of a relationship between interface shear stress and the overall horizontal stiffness measure, however, suggests that a pressure and shear force sensor should be used with the ISO 16840-2 horizontal stiffness measure to fully quantify a cushion's ability to reduce interface shear stress at the patient's bony prominences. PMID:21480097

Akins, Jonathan S; Karg, Patricia E; Brienza, David M

2011-01-01

305

A complete passive or imaging-based sensor system for unmanned air vehicle taking off and landing operations  

Microsoft Academic Search

We have successfully developed an innovative, miniaturized, and lightweight PTZ UCAV imager called OmniBird for unmanned air vehicle taking off and landing operations. OmniBird is developed through a SBIR funding from NAVAIR. It is to fit in 8 in3. The designed zoom capability allows it to acquire focused images for targets ranging from 10 to 250 feet. The innovative panning

Steven Yi

2008-01-01

306

Mixed-mode VLSI optic ow sensors for in-ight control of a micro air vehicle  

Microsoft Academic Search

ABSTRACT 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

G. Barrows; C. Neely

2000-01-01

307

Air Vehicle Technology Integration Program (AVTIP) Delivery Order 0015: Open Control Platform (OCP) Software Enabled Control (SEC) Hardware in the Loop Simulation - OCP Hardware Integration.  

National Technical Information Service (NTIS)

Boeing Phantom Works collaborated with Air Force Research Laboratory (AFRL) researchers at the Aerospace Vehicles Technology Assessment and Simulation (AVTAS) Laboratory and with Northrop Grumman to conduct the Open Control Platform (OCP) Hardware-In-The-...

J. L. Paunicka

2005-01-01

308

Characterization of Material Properties and Structural Dynamics of the Manduca Sexta Forewing for Application to Flapping Wing Micro Air Vehicle Design.  

National Technical Information Service (NTIS)

The Manduca Sexta species of moth serves as a source of biological inspiration for the future of micro air vehicle flapping flight. The ability of this species to hover in flapping flight has warranted investigation into the critical material, structural,...

R. P. O'Hara

2012-01-01

309

Clean Cities ozone air quality attainment and maintenance strategies that employ alternative fuel vehicles, with special emphasis on natural gas and propane  

Microsoft Academic Search

Air quality administrators across the nation are coming under greater pressure to find new strategies for further reducing automotive generated non-methane hydrocarbon (NMHC) and nitrogen oxide (NOx) emissions. The US Environmental Protection Agency (EPA) has established stringent emission reduction requirements for ozone non-attainment areas that have driven the vehicle industry to engineer vehicles meeting dramatically tightened standards. This paper describes

D. J. Santini; C. L. Saricks

1998-01-01

310

Ammonia emissions from a representative in-use fleet of light and medium-duty vehicles in the California South Coast Air Basin  

NASA Astrophysics Data System (ADS)

We used Fourier Transform Infrared Spectroscopy (FTIR) to measure tailpipe ammonia emissions from a representative fleet of 41 light and medium-duty vehicles recruited in the California South Coast Air Basin. A total of 121 chassis dynamometer emissions tests were conducted on these vehicles and the test results were examined to determine the effects of several key variables on ammonia emissions. Variables included vehicle type, driving cycle, emissions technology, ammonia precursor emissions (i.e. CO and NOx) and odometer readings/model year as a proxy for catalyst age. The mean ammonia emissions factor was 46 mg km -1 ( ? = 48 mg km -1) for the vehicle fleet. Average emission factors for specific vehicle groups are also reported in this study. Results of this study suggest vehicles with the highest ammonia emission rates possess the following characteristics: medium-duty vehicles, older emissions technologies, mid-range odometer readings, and higher CO emissions. In addition, vehicles subjected to aggressive driving conditions are likely to be higher ammonia emitters. Since the vehicles we studied were representative of recent model year vehicles and technologies in urban airsheds, the results of our study will be useful for developing ammonia emissions inventories in Los Angeles and other urban areas where California-certified vehicles are driven. However, efforts should also be made to continue emissions testing on in-use vehicles to ensure greater confidence in the ammonia emission factors reported here.

Livingston, Cody; Rieger, Paul; Winer, Arthur

311

FOG-2 Attenuates Endothelial-to-Mesenchymal Transformation in the Endocardial Cushions of the Developing Heart  

PubMed Central

Development of the heart valves is a complex process that relies on the successful remodeling of endocardial cushions. This process is dependent on a number of transcriptional regulators, including GATA4 and its interacting partner FOG-2. We have previously shown that the endocardial cushions in FOG-2 deficient mice are hyperplastic and fail to remodel appropriately, suggesting a defect late in endocardial cushion development. To elucidate this defect, we examined the later steps in endocardial cushion development including mesenchymal cell proliferation, differentiation, and apoptosis. We also measured myocardialization and endothelial-to-mesenchymal transformation (EMT) using previously described in vitro assays. We found no difference in the ability of the endocardial cushions to undergo myocardialization or in the rates of mesenchymal cell proliferation, differentiation, or apoptosis in the FOG-2 deficient cushions when compared to wild-type controls. However, using a collagen gel invasion assay, we found a 75% increase in outflow tract cushion EMT and a 35% increase in atrioventricular cushion EMT in the FOG-2 deficient mice when compared with wild-type mice. Taken together with GATA4’s known role in promoting EMT, these results suggest that FOG-2 functions in cardiac valve formation is as an attenuator of EMT by attenuating GATA4 activity within the developing endocardial cushions.

Flagg, Alleda E.; Earley, Judy U.; Svensson, Eric C.

2007-01-01

312

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

NASA Astrophysics Data System (ADS)

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.

Mettler, B. F.

2010-09-01

313

Attitude estimation and maneuvering for autonomous obstacle avoidance by miniature air vehicles  

Microsoft Academic Search

Utilizing the Euler-Rodrigues symmetric parameters (attitude quaternion) to describe vehicle orientation, we develop a multiplicative, nonlinear (extended) variation of the Kalman filter (MEKF) to fuse data from low-cost sensors. The sensor suite is comprised of gyroscopes, accelerometers, and a GPS receiver. In contrast to the common approach of using the complete vehicle attitude as the quantities to be estimated, our

James K. Hall

2009-01-01

314

Role of Individual and Team Cognition in Uninhabited Air Vehicle Command-and-Control.  

National Technical Information Service (NTIS)

This report documents a three-year AFOSR-funded research effort designed to study individual and team cognition in Unmanned Aerial Vehicle command-and-control. Three experiments were conducted in the CERTT lab's UAV-STE (Unmanned Aerial Vehicle - Syntheti...

H. K. Pedersen J. A. DeJoode J. C. Gorman N. J. Cooke O. O. Connor

2004-01-01

315

Drive train design enabling locomotion transition of a small hybrid air-land vehicle  

Microsoft Academic Search

Design modifications have improved the durability and performance of a previously developed hybrid vehicle capable of both aerial and terrestrial locomotion. Whereas the original vehicle could fly, land, and crawl in sequence, it suffered from limited durability, as evidenced by catastrophic failure after a small number of landings - two to four depending on the substrate. The two most common

Richard J. Bachmann; Ravi Vaidyanathan; Roger D. Quinn

2009-01-01

316

Air quality impacts of plug-in hybrid electric vehicles in Texas: evaluating three battery charging scenarios  

NASA Astrophysics Data System (ADS)

The air quality impacts of replacing approximately 20% of the gasoline-powered light duty vehicle miles traveled (VMT) with electric VMT by the year 2018 were examined for four major cities in Texas: Dallas/Ft Worth, Houston, Austin, and San Antonio. Plug-in hybrid electric vehicle (PHEV) charging was assumed to occur on the electric grid controlled by the Electricity Reliability Council of Texas (ERCOT), and three charging scenarios were examined: nighttime charging, charging to maximize battery life, and charging to maximize driver convenience. A subset of electricity generating units (EGUs) in Texas that were found to contribute the majority of the electricity generation needed to charge PHEVs at the times of day associated with each scenario was modeled using a regional photochemical model (CAMx). The net impacts of the PHEVs on the emissions of precursors to the formation of ozone included an increase in NOx emissions from EGUs during times of day when the vehicle is charging, and a decrease in NOx from mobile emissions. The changes in maximum daily 8 h ozone concentrations and average exposure potential at twelve air quality monitors in Texas were predicted on the basis of these changes in NOx emissions. For all scenarios, at all monitors, the impact of changes in vehicular emissions, rather than EGU emissions, dominated the ozone impact. In general, PHEVs lead to an increase in ozone during nighttime hours (due to decreased scavenging from both vehicles and EGU stacks) and a decrease in ozone during daytime hours. A few monitors showed a larger increase in ozone for the convenience charging scenario versus the other two scenarios. Additionally, cumulative ozone exposure results indicate that nighttime charging is most likely to reduce a measure of ozone exposure potential versus the other two scenarios.

Thompson, Tammy M.; King, Carey W.; Allen, David T.; Webber, Michael E.

2011-04-01

317

Discrete Event Simulation Model for Evaluating Air Force Reusable Military Launch Vehicle Prelaunch Operations.  

National Technical Information Service (NTIS)

As the control and exploitation of space becomes more important to the United States military, a responsive spacelift capability will become essential. Responsive spacelift could be defined as the ability to launch a vehicle within hours or days from the ...

A. T. Stiegelmeier

2006-01-01

318

75 FR 15620 - Federal Motor Vehicle Safety Standards; Air Brake Systems  

Federal Register 2010, 2011, 2012, 2013

...substantial improvements in stopping distance performance. In November 2009, the...Systems, to require improved stopping distance performance for truck tractors. The...vehicles to comply with the new stopping distance...

2010-03-30

319

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

National Technical Information Service (NTIS)

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 a...

C. L. Nickol L. L. Kohout M. D. Guynn T. A. Ozoroski

2007-01-01

320

Use of Energy-State Analysis on a Generic Air-Breathing Hypersonic Vehicle  

Microsoft Academic Search

A possible next-generation launch v ehicle may b e a fully reusable, single-stage-to-orbit (SSTO) aerospacecraft. This class of hypersonic vehicle includes highly integrated airframe and propulsion systems, h ence fuel-optimal t rajectories are of special i nterest. Also, since these vehicles are neither conventional aircraft nor r ockets, the a ppropriate a pproach for trajectory analysis during p reliminary d

David K. Schmidt; Jochen A. Hermann

1998-01-01

321

An air launched, highly responsive military transatmospheric vehicle (TAV), based on existing aerospace systems  

Microsoft Academic Search

A novel vehicle design is presented that minimizes Research Development Test and Evaluation (RDT&E) cost. The proposed TAV can satisfy a broad range of military mission applications for the 21st century. TAV deployment is provided by a Rockwell B-1B bomber. Pre-launch orientation of the vehicle is centerline, underneath the B-1B forward weapon bays. Launch occurs at 30,000 ft, Mach 0.90,

Kenneth R. Hampsten

1996-01-01

322

Measurement and modelling of the y-direction apparent mass of sitting human body-cushioned seat system  

NASA Astrophysics Data System (ADS)

Laboratory tests were conducted using 13 male subjects seated on a cushioned commercial vehicle driver's seat. The hands gripped a mock-up steering wheel and the subjects were in contact with the lumbar region of the backrest. The accelerations and forces in the y-direction were measured during random lateral whole-body vibration with a frequency range between 0.25 and 30 Hz, vibration magnitudes 0.30, 0.98, and 1.92 m s-2 (unweighted root mean square (rms)). Based on these laboratory measurements, a linear multi-degree-of-freedom (mdof) model of the seated human body and cushioned seat in the lateral direction (y-axis) was developed. Model parameters were identified from averaged measured apparent mass values (modulus and phase) for the three excitation magnitudes mentioned. A preferred model structure was selected from four 3-dof models analysed. The mean subject parameters were identified. In addition, identification of each subject's apparent mass model parameters was performed. The results are compared with previous studies. The developed model structure and the identified parameters can be used for further biodynamical research in seating dynamics.

Stein, George Juraj; Mú?ka, Peter; Hinz, Barbara; Blüthner, Ralph

2009-04-01

323

Twist1 function in endocardial cushion cell proliferation, migration, and differentiation during heart valve development  

PubMed Central

Twist1 is a bHLH transcription factor that regulates cell proliferation, migration, and differentiation in embryonic progenitor cell populations and transformed tumor cells. While much is known about Twist1’s function in a variety of mesenchymal cell types, the role of Twist1 in endocardial cushion cells is unknown. Twist1 gain and loss of function experiments were performed in primary chicken endocardial cushion cells in order to elucidate its role in endocardial cushion development. These studies indicate that Twist1 can induce endocardial cushion cell proliferation as well as promote endocardial cushion cell migration. Furthermore, Twist1 is subject to BMP regulation and can induce expression of cell migration marker genes including Periostin, Cadherin 11, and Mmp2 while repressing markers of valve cell differentiation including Aggrecan. Previously, Tbx20 has been implicated in endocardial cushion cell proliferation and differentiation, and in the current study, Tbx20 also promotes cushion cell migration. Twist1 can induce Tbx20 expression, while Tbx20 does not affect Twist1 expression. Taken together, these data indicate a role for Twist1 upstream of Tbx20 in promoting cell proliferation and migration and repressing differentiation in endocardial cushion cells during embryonic development.

Shelton, Elaine L.; Yutzey, Katherine E.

2008-01-01

324

Optimal control of helicopter seat cushions for the reduction of spinal injuries  

Microsoft Academic Search

The theoretically optimal performance of a helicopter seat cushion for the reduction of spinal injuries during vertical crashes is investigated using a limiting performance analysis. The spinal dynamic response index and the maximum spinal compression load are used as the system performance indices to be minimized. Three types of seat cushions (passive, active, and pre-acting) are studied. A trade-off curve

Z. Q. Cheng; W. D. Pilkey; D. V. Balandin; N. N. Bolotnik; J. R. Crandall; C. G. Shaw

2001-01-01

325

Fuel Cell Vehicle Fleet and Hydrogen Infrastructure at Hickam Air Force Base.  

National Technical Information Service (NTIS)

The US Air Force Advanced Power Technology Office (APTO) at Robins Air Force Base (AFB), Georgia, and the Hawaii Center for Advanced Transportation Technologies (HCATT) formed a partnership in 2001 to establish a National Demonstration Center at Hickam AF...

T. L. Quinn

2009-01-01

326

9 CFR 3.114 - Primary conveyances (motor vehicle, rail, air and marine).  

Code of Federal Regulations, 2013 CFR

...cargo spaces that have a supply of air sufficient for each live animal contained within. Primary transport enclosures must be positioned...will have access to sufficient air. (d) Primary transport enclosures must be...

2013-01-01

327

A complete passive or imaging-based sensor system for unmanned air vehicle taking off and landing operations  

NASA Astrophysics Data System (ADS)

We have successfully developed an innovative, miniaturized, and lightweight PTZ UCAV imager called OmniBird for unmanned air vehicle taking off and landing operations. OmniBird is developed through a SBIR funding from NAVAIR. It is to fit in 8 in3. The designed zoom capability allows it to acquire focused images for targets ranging from 10 to 250 feet. The innovative panning mechanism also allows the system to have a field of view of +/- 100 degrees. Initial test results show that the integrated optics, camera sensor, and mechanics solution allow the OmniBird to stay optically aligned and shock-proof under harsh environments.

Yi, Steven

2008-05-01

328

Suppression of the Variation of Cushion Pressure for SES Using Vertically Moving Nozzles  

NASA Astrophysics Data System (ADS)

In this paper the variation of cushion pressure is investigated theoretically to achieve comfortable riding of SES. A simpler and practical control method is proposed to control cushion pressure changes arising from pumping phenomenon that appears in SES cruising over the waves. Cushion pressure is controlled by varying the discharge height of the vertical nozzle. In this method the nozzle height (hover height) is kept constant according with the motion of the craft. As the result of investigations, cushion pressures are successfully controlled by the proposed method. In addition, it is shown that the pressure variation depends not only hover height but also on rate of change of cushion volume. Therefore it is also necessary to consider phase difference between the motion of models and the vertical displacement of nozzles.

Kanazawa, Koji; Matsuo, Kensuke; Matsuo, Hideo

329

Suppression of Variation in Cushion Pressure for SES Using Vertically Moving Nozzles  

NASA Astrophysics Data System (ADS)

In this paper, variation in cushion pressure is investigated theoretically to achieve SES ride comfort. A simple and practical control method is proposed to control cushion pressure changes caused by pumping that appears in SES cruising over waves. Cushion pressure is controlled by varying the discharge height of the vertical nozzle. In this method, the nozzle height (hover height) is kept constant according to craft motion. As the result of investigations, cushion pressures are controlled successfully by the proposed method. In addition, we show that the pressure variation depends both on hover heights and on the rates of change in cushion volume. Therefore, it is necessary to consider phase differences between craft motion and vertical nozzle displacements.

Kanazawa, Koji; Matsuo, Kensuke; Matsuo, Hideo

330

Ascent performance of an air-breathing horizontal-takeoff launch vehicle  

NASA Astrophysics Data System (ADS)

Simulations are conducted to investigate a proposed NASA launch vehicle that is fully reusable, takes off horizontally, and uses airbreathing propulsion in a single stage. The propulsion model is based on a cycle analysis method, and the vehicle is assumed to be a rigid structure with distributed fuel, operating under a range of atmospheric conditions. The program to optimize simulated trajectories (POST) is modified to include a predictor-corrector guidance capability and then used to generate the trajectories. Significant errors are encountered during the unpowered coast phase due to uncertainty in the atmospheric density profile. The amount of ascent propellant needed is shown to be directly related to the thrust-vector angle and the location of the center of gravity of the vehicle because of the importance of aim-drag losses to total ideal velocity.

Powell, Richard W.; Shaughnessy, John D.; Cruz, Christopher I.; Naftel, J. C.

1991-08-01

331

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

SciTech Connect

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.

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

1989-04-01

332

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

NASA Astrophysics Data System (ADS)

The superior flight characteristics exhibited by birds and insects can be taken as a prototype of the most perfect form of flying machine ever created. The design of Micro Air Vehicles (MAV) which tries mimic the flight of birds and insects has generated a great deal of interest as the MAVs can be utilized for a number of commercial and military operations which is usually not easily accessible by manned motion. The size and speed of operation of a MAV results in low Reynolds number flight, way below the flying conditions of a conventional aircraft. The insensitivity to wind shear and gust is one of the required factors to be considered in the design of airfoil for MAVs. The stability of flight under wind shear is successfully accomplished in the flight of birds and insects, through the flapping motion of their wings. Numerous studies which attempt to model the flapping motion of the birds and insects have neglected the effect of wind gust on the stability of the motion. Also sudden change in flight conditions makes it important to have the ability to have an instantaneous change of the lift force without disturbing the stability of the MAV. In the current study, two dimensional rigid airfoil, undergoing flapping motion is studied numerically using a compressible Navier-Stokes solver discretized using high-order finite difference schemes. The high-order schemes in space and in time are needed to keep the numerical solution economic in terms of computer resources and to prevent vortices from smearing. The numerical grid required for the computations are generated using an inverse panel method for the streamfunction and potential function. This grid generating algorithm allows the creation of single-block orthogonal H-grids with ease of clustering anywhere in the domain and the easy resolution of boundary layers. The developed numerical algorithm has been validated successfully against benchmark problems in computational aeroacoustics (CAA), and unsteady viscous flows. The numerical results for pure-plunge and pure-pitching motion of SD 7003 airfoil are compared with the particle image velocimetry data of Michael Ol by plotting the contours of streamwise velocity and vorticity and also by observing the wake profile of the streamwise velocity. A very good agreement in the location of the vortices was observed between the numerical and experimental results. Also the numerical tracking of streaklines was compared with the dye injection experiments and excellent agreement in the horizontal and vertical locations of the vortex cores was observed. The importance of using the angle of attack to match the wake structures and lift forces of airfoils in pure-pitch and pure-plunge was investigated and it was found that matching the plunging amplitude with the maximum displacement of the leading edge provides a closer match in the observed wake structures and coefficient of lift. Next, the average coefficient of list of an airfoil in pure-pitch was studied and it was found that the pitching about the leading edge produced the maximum value. Two difference methods of enhancements were considered: (i) axis of rotation, and (ii) moving airfoil, as possible ways to enhance the average coefficient of lift for an airfoil pitching about its leading edge. The first case produced two times increase and the second case produced almost four times increase in the average coefficient of lift respectively. Hence these two kinds of motion can be used for lift enhancement to overcome sudden changes in the flight conditions. Finally the effect of a sinusoidal gust on an airfoil in pure-pitch and pure-plunge motion was examined. The pitching motion showed a much lesser drop in the average coefficient of lift compared to the plunging motion, suggesting its effectiveness to overcome disturbances in the freestream. The plunging motion on the other hand can be employed for cases that require the suppression of the oscillation in the lift coefficient.

Gopalan, Harish

333

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

PubMed

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

Zbikowski, Rafa?

2002-02-15

334

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

NASA Astrophysics Data System (ADS)

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.

Pereira, Jason L.

335

The impact of plug-in vehicles on greenhouse gas and criteria pollutants emissions in an urban air shed using a spatially and temporally resolved dispatch model  

Microsoft Academic Search

With the introduction of plug-in vehicles (PEVs) into the light-duty vehicle fleet, the tail-pipe emissions of GHGs and criteria pollutants will be partly transferred to electricity generating units. To study the impact of PEVs on well-to-wheels emissions, the U.S. Western electrical grid serving the South Coast Air Basin (SoCAB) of California is modeled with both spatial and temporal resolution at

Ghazal Razeghi; Tim Brown; G. Scott Samuelsen

2011-01-01

336

Novel operation and control of an electric vehicle aluminum\\/air battery system  

Microsoft Academic Search

The objective of this paper is to create a method to size battery subsystems for an electric vehicle to optimize battery performance. Optimization of performance includes minimizing corrosion by operating at a constant current density. These subsystems will allow for easy mechanical recharging. A proper choice of battery subsystem will allow for longer battery life, greater range and performance. For

Xin Zhang; Shao Hua Yang; Harold Knickle

2004-01-01

337

SensorFlock: an airborne wireless sensor network of micro-air vehicles  

Microsoft Academic Search

An airborne wireless sensor network (WSN) composed of bird-sized micro aerial vehicles (MAVs) enables low cost high granularity atmospheric sensing of toxic plume be- havior and storm dynamics, and provides a unique three- dimensional vantage for monitoring wildlife and ecological systems. This paper describes a complete implementation of our SensorFlock airborne WSN, spanning the development of our MAV airplane, its

Jude Allred; Ahmad Bilal Hasan; Saroch Panichsakul; William Pisano; Peter Gray; Jyh Huang; Richard Han; Dale Lawrence; Kamran Mohseni

2007-01-01

338

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

Microsoft Academic Search

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

B. F. Mettler

2010-01-01

339

Lighter-Than-Air and Pressurized Structures Technology for Unmanned Aerial Vehicles (UAVs).  

National Technical Information Service (NTIS)

Several areas of unmanned aerial vehicle (UAV) performance need to be improved for the next generation of UAVs to be used successfully in expanded future combat roles. This report describes the initial research to improve the performance of UAVs through l...

A. Brown B. Roget H. Edge J. Collins M. Coatney

2010-01-01

340

Design Evolution and Performance Characterization of the GTX Air-Breathing Launch Vehicle Inlet.  

National Technical Information Service (NTIS)

The design and analysis of a second version of the inlet for the GTX rocket-based combine-cycle launch vehicle is discussed. The previous design did not achieve its predicted performance levels due to excessive turning of low-momentum corner flows and loc...

J. R. DeBonis C. J. Steffen T. Rice C. J. Trefny

2002-01-01

341

EFFECTS OF LOW REYNOLDS NUMBERS ON THE AERODYNAMICS OF MICRO AIR VEHICLES  

Microsoft Academic Search

Unmanned aerial vehicles (UAVs) come in various sizes and have several benefits. They are more compact, portable, capable of working in hazardous conditions, and cost effective than larger aircrafts, which often require the control of pilots inside of cockpits. Due to their novelty, there is still much research that must be done in this area. Topics of research include the

Shelly A. Migita

342

ANALYSIS OF MOTOR VEHICLE EMISSIONS IN A HOUSTON TUNNEL DURING THE TEXAS AIR QUALITY STUDY 2000  

EPA Science Inventory

Measurements from a Houston tunnel were used to develop fuel consumption based emission factors for CO, NOx, and Non-Methane Organic Compound (NMOC) for on-road gasoline vehicles. The Houston NOx emission factor was at the low range of emission factors reported in previous (pr...

343

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

Microsoft Academic Search

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

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

1999-01-01

344

9 CFR 3.37 - Primary conveyances (motor vehicle, rail, air, and marine).  

Code of Federal Regulations, 2013 CFR

...space that does not have a supply of air sufficient for normal breathing for each live animal contained therein, and the primary...guinea pig or hamster has access to sufficient air for normal breathing. (d) Primary enclosures shall be positioned in...

2013-01-01

345

BMP-2 Induces Versican and Hyaluronan That Contribute to Post-EMT AV Cushion Cell Migration  

PubMed Central

Distal outgrowth and maturation of mesenchymalized endocardial cushions are critical morphogenetic events during post-EMT atrioventricular (AV) valvuloseptal morphogenesis. We explored the role of BMP-2 in the regulation of valvulogenic extracellular matrix (ECM) components, versican and hyaluronan (HA), and cell migration during post-EMT AV cushion distal outgrowth/expansion. We observed intense staining of versican and HA in AV cushion mesenchyme from the early cushion expansion stage, Hamburger and Hamilton (HH) stage-17 to the cushion maturation stage, HH stage-29 in the chick. Based on this expression pattern we examined the role of BMP-2 in regulating versican and HA using 3D AV cushion mesenchymal cell (CMC) aggregate cultures on hydrated collagen gels. BMP-2 induced versican expression and HA deposition as well as mRNA expression of versican and Has2 by CMCs in a dose dependent manner. Noggin, an antagonist of BMP, abolished BMP-2-induced versican and HA as well as mRNA expression of versican and Has2. We further examined whether BMP-2-promoted cell migration was associated with expression of versican and HA. BMP-2- promoted cell migration was significantly impaired by treatments with versican siRNA and HA oligomer. In conclusion, we provide evidence that BMP-2 induces expression of versican and HA by AV CMCs and that these ECM components contribute to BMP-2-induced CMC migration, indicating critical roles for BMP-2 in distal outgrowth/expansion of mesenchymalized AV cushions.

Inai, Kei; Burnside, Jessica L.; Hoffman, Stanley; Toole, Bryan P.; Sugi, Yukiko

2013-01-01

346

BMP-2 Induces Versican and Hyaluronan That Contribute to Post-EMT AV Cushion Cell Migration.  

PubMed

Distal outgrowth and maturation of mesenchymalized endocardial cushions are critical morphogenetic events during post-EMT atrioventricular (AV) valvuloseptal morphogenesis. We explored the role of BMP-2 in the regulation of valvulogenic extracellular matrix (ECM) components, versican and hyaluronan (HA), and cell migration during post-EMT AV cushion distal outgrowth/expansion. We observed intense staining of versican and HA in AV cushion mesenchyme from the early cushion expansion stage, Hamburger and Hamilton (HH) stage-17 to the cushion maturation stage, HH stage-29 in the chick. Based on this expression pattern we examined the role of BMP-2 in regulating versican and HA using 3D AV cushion mesenchymal cell (CMC) aggregate cultures on hydrated collagen gels. BMP-2 induced versican expression and HA deposition as well as mRNA expression of versican and Has2 by CMCs in a dose dependent manner. Noggin, an antagonist of BMP, abolished BMP-2-induced versican and HA as well as mRNA expression of versican and Has2. We further examined whether BMP-2-promoted cell migration was associated with expression of versican and HA. BMP-2- promoted cell migration was significantly impaired by treatments with versican siRNA and HA oligomer. In conclusion, we provide evidence that BMP-2 induces expression of versican and HA by AV CMCs and that these ECM components contribute to BMP-2-induced CMC migration, indicating critical roles for BMP-2 in distal outgrowth/expansion of mesenchymalized AV cushions. PMID:24147033

Inai, Kei; Burnside, Jessica L; Hoffman, Stanley; Toole, Bryan P; Sugi, Yukiko

2013-10-11

347

The Effect of Mixing and Gravitational Segregation Between Natural Gas and Inert Cushion Gas on the Recovery of Gas from Horizontal Storage Aquifers  

Microsoft Academic Search

It has been proposed in the literature that certain economies might result from the use of an inert cushion gas, such as flue gas, during the storage of natural gas in aquifers. Where cushion gas is used, 2 types of displacement occur: (1) miscible displacement at the natural gas-cushion gas boundary and (2) immiscible displacement at the cushion gas-water interface.

Anil Kumar; Oscar Kimbler

1972-01-01

348

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

Microsoft Academic Search

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)

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

2005-01-01

349

Design and development of effective manual control system for unmanned air vehicle  

Microsoft Academic Search

Unmanned Aerial Vehicles (UAVs) are remotely piloted or self-piloted aircraft that are capable of flight without any on-board operator and can carry cameras, sensors, communications equipment or other payloads. UAVs have been used in a reconnaissance and intelligence-gathering role, including combat and rescue missions. This paper describes development and implementation of remote manual control system for a UAV. The paper

Muhammad Aamir Zafar; Ansar Rauf; Zeeshan Ashraf; Humza Akhtar

2011-01-01

350

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

Microsoft Academic Search

This paper describes a methodology to extract aerial vehicles’ aerodynamic characteristics from visually tracked trajectory\\u000a data. The technique is being developed to study the aerodynamics of centimeter-scale aircraft and develop flight simulation\\u000a models. Centimeter-scale aircraft remains a largely unstudied domain of aerodynamics, for which traditional techniques like\\u000a wind tunnels and computational fluid dynamics have not yet been fully adapted and

B. F. Mettler

2010-01-01

351

76 FR 23879 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Removal of Vehicle...  

Federal Register 2010, 2011, 2012, 2013

...and Floyd Counties 1997 8-Hour Ozone Maintenance Plan. On January 12...nonattainment area for the 1997 8-hour ozone NAAQS, and air quality data are...that the emission could destroy the ozone layer and harm people's health...

2011-04-29

352

Weight and volume estimates for aluminum-air batteries designed for electric vehicle applications  

Microsoft Academic Search

The weights and volumes of reactants, electrolyte, and hardware components are estimated for an aluminum-air battery designed for a 40-kW (peak), 70-kWh aluminum-air battery. Generalized equations are derived which express battery power and energy content as functions of total anode area, aluminum-anode weight, and discharge current density. Equations are also presented which express total battery weight and volume as linear

J. F. Cooper

1980-01-01

353

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

Microsoft Academic Search

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

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

354

Effects of Vehicle Interior Geometry and Anthropometric Variables on Automobile Driving Posture  

Microsoft Academic Search

The effects of vehicle package, seat, and anthropometric variables on posture were studied in a laboratory vehicle mockup. Participants (68 men and women) selected their preferred driving postures in 18 combinations of seat height, fore-aft steering wheel position, and seat cushion angle. Two seats differing in stiffness and seat back contour were used in testing. Driving postures were recorded using

Matthew P. Reed; Miriam A. Manary; Carol A. C. Flannagan; Lawrence W. Schneider

2000-01-01

355

Air  

MedlinePLUS

... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

356

Polymer packaging for arrayed ionic polymer-metal composites and its application to micro air vehicle control surface  

NASA Astrophysics Data System (ADS)

In this study, ionic polymer-metal composite (IPMC) actuators arrayed in horizontal as well as vertical directions were investigated for more effective actuation performance. A very thin polymer packaging structure named 'glove' was designed and fabricated, and the IPMC package, composed of the glove and the arrayed IPMCs, was applied to the multifunctional control surface of a micro air vehicle (MAV). The IPMC package is light and space-saving, and therefore appropriate for the application of a MAV which has a limitation in weight and size. A wind tunnel test was performed to demonstrate the capability of the IPMC package for the control surface of a MAV and it was confirmed that the package generates enough force to maneuver a MAV.

Kim, Seong Jun; Cho, Chahngmin; Hyup Kim, Yong

2009-11-01

357

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

NASA Astrophysics Data System (ADS)

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

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

2010-12-01

358

Safety flier--a parachute-glider air-vehicle with vertical take-off and landing capability  

US Patent & Trademark Office Database

One embodiment of a Vertical Take-off and Landing (VToL) air-vehicle (FIG. 1.) having a horizontal rotor, a. providing lift and propulsion, and communicating at or near its centre to structural elements, or fuselage, b. Upon or within the fuselage structure is attached a platform, to which a payload, or occupant or pilot, d. is secured in such a manner as to permit a movement, or range-of-motion, of the payload, as a means of weight-shifting, or mass-balancing, of the vehicle for stability and control in flight. At least two planar elements, or descent-vanes, c.i & c.ii are connected to a structural element of the fuselage at a location which provides vertical and horizontal separation between the rotor and the descent-vanes, thus creating a tandem, biplane arrangement of two aerodynamically active elements which are aerodynamically balanced to provide stability and controllability in hovering flight, in forward flight, and in un-powered gliding and vertical descents. Other embodiments are described and shown.

2013-04-02

359

Development of Configurations and Combinations of Polyurethane Foam to Produce Maximum Efficiency in Package Cushioning Materials.  

National Technical Information Service (NTIS)

Engineering criteria were obtained through case drops simulating field conditions as closely as possible. Data were obtained at various drop heights on cushions made according to standard construction techniques. Six types of foam were utilized in this st...

M. Palmer

1967-01-01

360

Development of Configurations and Combinations of Polyurethane Foam to Produce Maximum Efficiency in Package Cushioning Materials.  

National Technical Information Service (NTIS)

The study was utilized to determine optimum cushioning techniques for various static loads at different drop heights. In order to secure accuracy, all static and dynamic tests were standardized. Also, physical characteristics were determined for all cushi...

M. Palmer

1967-01-01

361

Alpine cushion plants inhibit the loss of phylogenetic diversity in severe environments.  

PubMed

Biotic interactions can shape phylogenetic community structure (PCS). However, we do not know how the asymmetric effects of foundation species on communities extend to effects on PCS. We assessed PCS of alpine plant communities around the world, both within cushion plant foundation species and adjacent open ground, and compared the effects of foundation species and climate on alpha (within-microsite), beta (between open and cushion) and gamma (open and cushion combined) PCS. In the open, alpha PCS shifted from highly related to distantly related with increasing potential productivity. However, we found no relationship between gamma PCS and climate, due to divergence in phylogenetic composition between cushion and open sub-communities in severe environments, as demonstrated by increasing phylo-beta diversity. Thus, foundation species functioned as micro-refugia by facilitating less stress-tolerant lineages in severe environments, erasing a global productivity - phylogenetic diversity relationship that would go undetected without accounting for this important biotic interaction. PMID:23346919

Butterfield, B J; Cavieres, L A; Callaway, R M; Cook, B J; Kikvidze, Z; Lortie, C J; Michalet, R; Pugnaire, F I; Schöb, C; Xiao, S; Zaitchek, B; Anthelme, F; Björk, R G; Dickinson, K; Gavilán, R; Kanka, R; Maalouf, J-P; Noroozi, J; Parajuli, R; Phoenix, G K; Reid, A; Ridenour, W; Rixen, C; Wipf, S; Zhao, L; Brooker, R W

2013-01-24

362

Vehicle emissions  

NSDL National Science Digital Library

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

Project, Iowa P.

2004-01-01

363

Unusual basal skull fracture in a vehicle equipped with an air bag.  

PubMed

A woman who was the lap/shoulder belt-restrained driver of a car equipped with a full-size air bag was involved in an oblique frontal collision with a tractor-trailer combination. She was extremely out of position, i.e., witnessed to be slumped over the steering wheel before impact. This preimpact positioning led to fatal injuries resulting from the inflating air bag. Postmortem examination showed an unusual partial ring fracture of the base of the skull, which to the authors' knowledge has not previously been reported. PMID:11563734

Bandstra, R A; Carbone, L S

2001-09-01

364

Misuse of booster cushions - an observation study of children's performance during buckling up.  

PubMed

Booster cushions are effective tools to protect children from injuries in car crashes, but there remains a large amount of misuse. The aim of this study was to assess potential misuse of booster cushions in an observational laboratory study, and to identify whether booster cushion design, age or clothing had any effect. 130 Swedish children from the ages of 4-12 years participated. Each child buckled up on an integrated and on an aftermarket booster cushion in the rear seat. The older children also buckled up with seat belt only. Interviews, observations and body measurements were performed. Time to buckle up and amount of belt slack were registered. Photographs were taken to document misuse. Results showed that 77% failed to perform correct belt routing on the aftermarket cushion, independent of age, although they were familiar with this system. The misuse rate for the integrated cushion was only 4%. No misuse was found for seat belt only. Few children tightened the belt. The belt slack increased when wearing winter jackets. This indicates the importance of adding pretensioners to the rear seat. Sled tests with HIII&TNO 6y dummies were also performed for the most frequent misuse situations found. The main conclusion is that an integrated booster cushion has many advantages compared to an aftermarket cushion regarding both safety and comfort. It is easy and quick to handle, has few possibilities for misuse, has an intuitive design, the buckling up sequence is equal to buckling up with an ordinary seat belt, and younger children can buckle up correctly. PMID:19026222

Osvalder, Anna-Lisa; Bohman, Katarina

2008-10-01

365

eCushion: An eTextile Device for Sitting Posture Monitoring  

Microsoft Academic Search

Sitting posture analysis is critical for daily appli- cations in biomedical, education and healthcare fields. However, it remains unclear how to monitor sitting posture economically and comfortably. To this end, we presented an eTextile device, called eCushion, in this paper, which can analyze the sitting posture of human being accurately and non-invasively. First, we discussed the implementation of eCushion and

Wenyao Xu; Zhinan Li; Ming-Chun Huang; Navid Amini; Majid Sarrafzadeh

2011-01-01

366

An investigation of drag reduction for tractor trailer vehicles with air deflector and boattail. Final report  

SciTech Connect

A wind tunnel investigation was conducted to determine the influence of several physical variables on the aerodynamic drag of a trailer model. The physical variables included: a cab mounted wind deflector, boattail on trailer, flow vanes on trailer front, forced transition on trailer, and decreased gap between tractor and trailer. Tests were conducted at yaw angles (relative wind angles) of 0, 5, 10, 20, and 30 degrees and Reynolds numbers of 3.58 x 10 to the 5th power 6.12 x 10 to the 5th power based upon the equivalent diameter of the vehicles. The wind deflector on top of the cab produced a calculated reduction in fuel consumption of about 5 percent of the aerodynamic portion of the fuel budget for a wind speed of 15.3 km/hr (9.5 mph) over a wind angle range of 0 deg to 180 deg and for a vehicle speed of 88.5 km/hr (55 mph). The boattail produced a calculated 7 percent to 8 percent reduction in fuel consumption under the same conditions. The decrease in gap reduced the calculated fuel consumption by about 5 percent of the aerodynamic portion of the fuel budget.

Muirhead, V.U.

1981-01-01

367

Control system considerations for an aluminum-air battery powered electric vehicle  

NASA Astrophysics Data System (ADS)

Basic motor controller requirements and tradeoffs between 30 cell and 60 cell aluminum air battery systems were established. A sample controller design was evolved and basic characteristics were evaluated. Advantages of a 60 cell battery system over a 30 cell were found in the areas of control system costs, weights, and efficiency.

Cox, L. E.; Hassman, G. V.; Post, S. F.

1980-05-01

368

Control system considerations for an aluminum-air battery powered electric vehicle. Final report  

Microsoft Academic Search

The study established basic motor-controller requirements and trade-offs between 30-cell and 60-cell aluminum-air battery systems. A sample controller design was evolved and basic characteristics were evaluated. Advantages of a 60-cell battery system over a 30-cell were found in the areas of control system costs, weights, and efficiency.

L. E. Cox; G. V. Hassman; S. F. Post

1980-01-01

369

Control system considerations for an aluminum-air battery powered electric vehicle  

Microsoft Academic Search

Basic motor controller requirements and tradeoffs between 30 cell and 60 cell aluminum air battery systems were established. A sample controller design was evolved and basic characteristics were evaluated. Advantages of a 60 cell battery system over a 30 cell were found in the areas of control system costs, weights, and efficiency.

L. E. Cox; G. V. Hassman; S. F. Post

1980-01-01

370

Field Evaluation of Built-In Test Equipment (BITE) for Vehicle Oil and Air Contamination.  

National Technical Information Service (NTIS)

A two-phase, three-year project has been completed to select and evaluate candidate commercially available Built-In Test Equipment (BITE) for monitoring diesel engine crankcase lubricant quality (Oil-BITE) and engine induction system are quality (Air-BITE...

R. A. Alvarez J. D. Tosh J. A. Russell F. M. Newman

1981-01-01

371

Nonlinear air-to-fuel ratio and engine speed control for hybrid vehicles  

Microsoft Academic Search

Internal combustion spark ignition engine management systems regulate the fuel, spark, and idle air subsystems to achieve sufficient engine performance at acceptable fuel economy and tailpipe emission levels. Engine control units also monitor other engine processes, using a suite of sensors, and periodically check the system actuators' operation to satisfy legislated onboard diagnostics. The majority of production engines regulate the

John R. Wagner; Darren M. Dawson; Liu Zeyu

2003-01-01

372

INCORPORATION OF PASSIVE WING FOLDING IN FLAPPING WING MINIATURE AIR VEHICLES  

Microsoft Academic Search

Flapping wing motion produces positive lift in the down stroke and negative lift in the upstroke under zero forward velocity. Large birds frequently exhibit flight behavior where their wings are folded during the upstroke, thus lowering the air resistance as the wing is moved upwards. The result is reduced magnitude of negative lift produced during the upstroke, relative to the

Dominik Mueller; John W. Gerdes; Satyandra K. Gupta

373

Lithium Requirements for Electric Vehicles Using Lithium-Water-Air Batteries.  

National Technical Information Service (NTIS)

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 sub 2 are ...

B. Rubin H. Wiesner I. Y. Borg J. F. Cooper L. G. B. E. O'Connell

1975-01-01

374

Zero methane emission bogs: extreme rhizosphere oxygenation by cushion plants in Patagonia.  

PubMed

• Vascular wetland plants may substantially increase methane emissions by producing root exudates and easily degradable litter, and by providing a low-resistance diffusion pathway via their aerenchyma. However, model studies have indicated that vascular plants can reduce methane emission when soil oxygen demand is exceeded by oxygen released from roots. Here, we tested whether these conditions occur in bogs dominated by cushion plants. • Root-methane interactions were studied by comparing methane emissions, stock and oxygen availability in depth profiles below lawns of either cushion plants or Sphagnum mosses in Patagonia. • Cushion plants, Astelia pumila and Donatia fascicularis, formed extensive root systems up to 120 cm in depth. The cold soil (< 10°C) and highly decomposed peat resulted in low microbial activity and oxygen consumption. In cushion plant lawns, high soil oxygen coincided with high root densities, but methane emissions were absent. In Sphagnum lawns, methane emissions were substantial. High methane concentrations were only found in soils without cushion plant roots. • This first methane study in Patagonian bog vegetation reveals lower emissions than expected. We conclude that cushion plants are capable of reducing methane emission on an ecosystem scale by thorough soil and methane oxidation. PMID:21232058

Fritz, Christian; Pancotto, Veronica A; Elzenga, Josephus T M; Visser, Eric J W; Grootjans, Ab P; Pol, Arjan; Iturraspe, Rodolfo; Roelofs, Jan G M; Smolders, Alfons J P

2011-01-14

375

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

PubMed

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

Chan, Woei-Leong; Hsiao, Fei-Bin

2011-03-28

376

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

PubMed Central

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.

Chan, Woei-Leong; Hsiao, Fei-Bin

2011-01-01

377

Analysis of Motor Vehicle Emissions in a Houston Tunnel during the Texas Air Quality Study 2000  

NASA Astrophysics Data System (ADS)

Measurements collected in a Houston tunnel were used to develop CO, NOx, and Non-Methane Organic Compound (NMOC) emission factors for on-road gasoline vehicles. The Houston NOx emission factor was at the lower range of emission factors reported in previous (primarily pre-1996) tunnel studies while the Houston NMOC emission factor was slightly higher than the emission factors reported in the previous tunnel studies. Comparison of individual hydrocarbon concentration ratios based on the tunnel data to ratios based on data obtained by aircraft flying at low levels over major transportation corridors showed relatively higher ratios of most hydrocarbon concentrations to MTBE and acetylene in the ambient environment than in the tunnel.

McGaughey, G. R.; Desai, N. R.; Allen, D. T.; Seila, R. L.; Lonneman, W. A.; Fraser, M. P.; Harley, R. A.; Ivy, J. M.; Price, J. H.

2002-12-01

378

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

NASA Astrophysics Data System (ADS)

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.

Azrad, Syaril; Kendoul, Farid; Nonami, Kenzo

379

Design and development of an unconventional VTOL micro air vehicle: The Cyclocopter  

NASA Astrophysics Data System (ADS)

This paper discusses the systematic experimental and vehicle design/development studies conducted at the University of Maryland which culminated in the development of the first flying Cyclocopter in the history. Cyclocopter is a novel Vertical Take-Off and Landing (VTOL) aircraft, which utilizes cycloidalrotors (cyclorotors), a revolutionary horizontal axis propulsion concept, that has many advantages such as higher aerodynamic efficiency, maneuverability and high-speed forward flight capability when compared to a conventional helicopter rotor. The experimental studies included a detailed parametric study to understand the effect of rotor geometry and blade kinematics on cyclorotor hover performance. Based on the experimental results, higher blade pitch angles were found to improve thrust and increase the power loading (thrust per unit power) of the cyclorotor. Asymmetric pitching with higher pitch angle at the top than at the bottom produced better power loading. The chordwise optimum pitching axis location was observed to be around 25-35% of the blade chord. Because of the flow curvature effects, the cycloidal rotor performance was a strong function of the chord/radius ratio. The optimum chord/radius ratios were extremely high, around 0.5-0.8, depending on the blade pitching amplitude. A flow field investigation was also conducted using Particle Image Velocimetry (PIV) to unravel the physics behind thrust production of a cyclorotor. PIV studies indicated evidence of a stall delay as well as possible increases in lift on the blades from the presence of a leading edge vortex. The goal of all these studies was to understand and optimize the performance of a micro-scale cyclorotor so that it could be used in a flying vehicle. An optimized cyclorotor was used to develop a 200 gram cyclocopter capable of autonomous stable hover using an onboard feedback controller.

Benedict, Moble; Chopra, Inderjit

2012-05-01

380

AUTOPILOT DEVELOPMENT FOR A MICRO AIR VEHICLE USING VISION-BASED ATTITUDE ESTIMATION  

Microsoft Academic Search

ACKNOWLEDGMENTS I would like to acknowledge AFRL-MN and the management,at Eglin Air Force Base because none of this work would have been possible without their continued nancial,support. I would also like to extend thanks to Dr. Peter Ifju and his students Kyu Ho Lee and Sewoong Jung, along with the entire MAV Lab for the design, development, and fabrication of

JOSEPH JOHN KEHOE

381

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

Microsoft Academic Search

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

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

1975-01-01

382

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

Microsoft Academic Search

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

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

1975-01-01

383

Structural studies of lipid-protein interactions on cushioned bilayers  

NASA Astrophysics Data System (ADS)

Biological membranes are heterogeneous and dynamical organizations of lipids and proteins, which perform functions fundamental to cell survival. Lipid-protein interactions control these functions by influencing folding and stability of integral or peripheral membrane proteins. Further, the incorporation or adsorption of these proteins into the membrane can in turn influence the lipid bilayer properties. In spite of some progress in understanding this process, a detailed structural analysis is lacking. Towards a better understanding of this interaction, we have performed an advanced interface sensitive scattering experiment using synchrotron x-rays. To accurately mimic the biological membranes with their natural thermal fluctuations and in-plane mobility of lipid molecules, polymer cushioned lipid bilayers have been used. This study shows that the adsorption of peripheral membrane proteinspectrindepends on the lipid headgroups, exhibiting different types of binding to phosphatidylcholine (PC) and phosphatidylethanolamie (PE). Further, the interaction of outer membrane protein A (OMP-A), an integral membrane protein is sensitive to the thermodynamic phase of the lipids. A detailed physical modeling of the lipid-protein interactions is under way.

Ghosh, S. K.; Mukhopadhyay, M. K.; Ma, Y.; Lopez, I.; Bera, S.; Lurio, L. B.; Chakrabarti, A.; Kim, J. E.; Sanyal, M. K.; Sinha, S. K.

2013-03-01

384

[Current status of air pollution in Sao Paulo, Brazil: effects and problems associated with the introduction of ethanol-fueled motor vehicles].  

PubMed

Recently suggestions have been advanced that alternative fuels including ethanol, methanol or methane instead of so called "fossil fuels" may help improve the current conditions of air pollution. According to results of general survey in Sao Paulo, since their introduction in 1978, ethanol-fueled cars have increased their share to almost 50% of all light vehicles in 1983. The current status of air pollution in Sao Paulo metropolitan area (SPMA) is described in relation to the use of such alternative fuel. The average concentrations in air of SO2 and lead have been decreasing drastically during the period of 1982-88, whereas non-methane hydrocarbon, NO2 and O3 levels have been increasing to attain the worst levels in the world as indicated in Fig. 2. The use of ethanol-fuel, which contains less sulphate and lead, is thought to have contributed more or less to the above reductions of SO2 and lead in the air. However, the pollutants that have increased may derive mainly from diesel and gasoline exhausts of heavy vehicles. The general state of air pollutions appears not to have been improved, suggesting the difficulty in resolving air pollution issues. On the other hand, a current problem specific to ethanol-fuel is the aldehydes or other carcinogenic components in exhaust. Peak formaldehyde concentration, for example, have been reported to have reached 159 ppb in SPMA, which may be one of the highest levels shown in ambient air.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1720061

Kabuto, M; Tsugane, S; Hamada, G S

1990-05-01

385

Water cooling system for an air-breathing hypersonic test vehicle  

NASA Astrophysics Data System (ADS)

This study provides concepts for hypersonic experimental scramjet test vehicles which have low cost and low risk. Cryogenic hydrogen is used as the fuel and coolant. Secondary water cooling systems were designed. Three concepts are shown: an all hydrogen cooling system, a secondary open loop water cooled system, and a secondary closed loop water cooled system. The open loop concept uses high pressure helium (15,000 psi) to drive water through the cooling system while maintaining the pressure in the water tank. The water flows through the turbine side of the turbopump to pump hydrogen fuel. The water is then allowed to vent. In the closed loop concept high pressure, room temperature, compressed liquid water is circulated. In flight water pressure is limited to 6000 psi by venting some of the water. Water is circulated through cooling channels via an ejector which uses high pressure gas to drive a water jet. The cooling systems are presented along with finite difference steady-state and transient analysis results. The results from this study indicate that water used as a secondary coolant can be designed to increase experimental test time, produce minimum venting of fluid and reduce overall development cost.

Petley, Dennis H.; Dziedzic, William M.

1993-06-01

386

VisNAV 100: a robust, compact imaging sensor for enabling autonomous air-to-air refueling of aircraft and unmanned aerial vehicles  

NASA Astrophysics Data System (ADS)

To enable autonomous air-to-refueling of manned and unmanned vehicles a robust high speed relative navigation sensor capable of proving high accuracy 3DOF information in diverse operating conditions is required. To help address this problem, StarVision Technologies Inc. has been developing a compact, high update rate (100Hz), wide field-of-view (90deg) direction and range estimation imaging sensor called VisNAV 100. The sensor is fully autonomous requiring no communication from the tanker aircraft and contains high reliability embedded avionics to provide range, azimuth, elevation (3 degrees of freedom solution 3DOF) and closing speed relative to the tanker aircraft. The sensor is capable of providing 3DOF with an error of 1% in range and 0.1deg in azimuth/elevation up to a range of 30m and 1 deg error in direction for ranges up to 200m at 100Hz update rates. In this paper we will discuss the algorithms that were developed in-house to enable robust beacon pattern detection, outlier rejection and 3DOF estimation in adverse conditions and present the results of several outdoor tests. Results from the long range single beacon detection tests will also be discussed.

Katake, Anup; Choi, Heeyoul

2010-02-01

387

BATMAV: a biologically inspired micro air vehicle for flapping flight: kinematic modeling  

NASA Astrophysics Data System (ADS)

The overall objective of the BATMAV project is the development of a biologically inspired bat-like Micro-Aerial Vehicle (MAV) with flexible and foldable wings, capable of flapping flight. This first phase of the project focuses particularly on the kinematical analysis of the wing motion in order to build an artificial-muscle-driven actuation system in the future. While flapping flight in MAV has been previously studied and a number of models were realized using light-weight nature-inspired rigid wings, this paper presents a first model for a platform that features bat-inspired wings with a number of flexible joints which allows mimicking the kinematics of the real flyer. The bat was chosen after an extensive analysis of the flight physics of small birds, bats and large insects characterized by superior gust rejection and obstacle avoidance. Typical engineering parameters such as wing loading, wing beat frequency etc. were studied and it was concluded that bats are a suitable platform that can be actuated efficiently using artificial muscles. Also, due to their wing camber variation, they can operate effectively at a large range of speeds and allow remarkably maneuverable flight. In order to understand how to implement the artificial muscles on a bat-like platform, the analysis was followed by a study of bat flight kinematics. Due to their obvious complexity, only a limited number of degrees of freedom (DOF) were selected to characterize the flexible wing's stroke pattern. An extended analysis of flight styles in bats based on the data collected by Norberg and the engineering theory of robotic manipulators resulted in a 2 and 4-DOF models which managed to mimic the wingbeat cycle of the natural flyer. The results of the kinematical model can be used to optimize the lengths and the attachment locations of the wires such that enough lift, thrust and wing stroke are obtained.

Bunget, Gheorghe; Seelecke, Stefan

2008-05-01

388

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

PubMed

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

Saracoglu, Sibel; Soylak, Mustafa; Elçi, Latif

389

Aerodynamics of low aspect ratio wings at low Reynolds numbers with applications to micro air vehicle design  

NASA Astrophysics Data System (ADS)

The recent interest in the development of small UAVs and micro air vehicles has revealed a need for a more thorough understanding of the aerodynamics of small airplanes flying at low speeds. In response to this need, the present work presents a study of the lift, drag, and pitching moment characteristics of wings of low aspect ratio operating at low Reynolds numbers. Wind tunnel tests of wings with aspect ratios between 0.5 and 2.0, four distinct planforms, thickness-to-chord ratios of ?2%, and 5-to-1 elliptical leading edges have been conducted as part of this research. The Reynolds numbers considered were in the range of 70,000 to 200,000. Analysis of the data includes comparison of lift-curve slope, induced-drag coefficient, and maximum lift coefficient with theory, discussion of aerodynamic center, and the effects of Reynolds number, camber, and leading-edge shape. As an example of an application of this wind tunnel data, the experimental results are implemented within an aircraft performance prediction procedure. This procedure is incorporated into a genetic algorithm optimization program that identifies near-optimum MAV configurations given certain requirements and constraints. Results obtained by use of this optimization procedure have revealed that useful design tools can be developed based on the experimental database.

Torres, Gabriel Eduardo

2002-09-01

390

Aerodynamic Characteristics of 4% Cambered-Plate and NACA0012 Airfoil at the Reynolds Numbers Region for Micro Air Vehicles  

NASA Astrophysics Data System (ADS)

In the Reynolds number region lower than approximately 1.0 × 105, which corresponds to the Reynolds number region of a Micro Air Vehicle, thinner and sharper leading edge airfoil performs better than thicker and blunter one. This research focuses on the difference in flowfields which are clarified by means of streamline calculation and surface pressure distribution measurement. Numerical studies were performed to the blunt type NACA0012 airfoil and both numerical and experimental studies were performed to the thinner type 4% cambered-plate airfoil. The performance of the NACA0012 airfoil is deteriorated with decreasing Reynolds number, whereas that of the 4% circular arc cambered-plate airfoil is not affected. The deterioration of the NACA0012 airfoil performance is mainly due to the laminar boundary layer separation near the trailing edge; such phenomena are not essential to the performance in the cambered-plate airfoil results. This paper also demonstrates that the flow separation at the trailing edge can be estimated from the temporal amplification factor of the oscillatory mode which is calculated by the global linear stability analysis.

??, ??; ??, ??; ??, ??

391

Models and algorithms for solving combined vehicle and crew scheduling problems with rest constraints : an application to road feeder service planning in air cargo transportation  

Microsoft Academic Search

We present a mathematical model and two algorithms for solving a complex combined vehicle and crew scheduling problem. The\\u000a problem arises in the area of road feeder service (RFS) for air cargo transportation where cargo airlines engage specifically\\u000a equipped RFS-carriers to serve so-called lines, i.e. regular weekly patterns of trips starting and ending at the central hub,\\u000a respectively. The complexity

P. Bartodziej; U. Derigs; D. Malcherek; U. Vogel

2009-01-01

392

MEKK3 initiates TGF?2-dependent EMT during endocardial cushion morphogenesis  

PubMed Central

Congenital heart defects (CHDs) occur at a rate of five percent and are the most prevalent birth defects. A better understanding of the complex signaling networks regulating heart development is necessary to improve repair strategies for CHDs. The MAP3 kinase, MEKK3, is important to early embryogenesis, but developmental processes affected by MEKK3 during heart morphogenesis have not been fully examined. We identify MEKK3 as a critical signaling molecule during endocardial cushion development. We report the detection of MEKK3 transcripts to embryonic hearts prior, during and after cardiac cushion cells have executed epithelial to mesenchymal transformation (EMT). MEKK3 is observed to endocardial cells of the cardiac cushions with a diminishing gradient of expression into the cushions. These observations suggest that MEKK3 may function during production of cushion mesenchyme as required for valvular development and septation of the heart. We used a kinase inactive form of MEKK3 (MEKK3KI) in an in vitro assay that recapitulates in vivo EMT, and show that MEKK3KI attenuates mesenchyme formation. Conversely, constitutively active MEKK3 (ca-MEKK3) triggers mesenchyme production in ventricular endocardium, a tissue that does not normally undergo EMT. MEKK3-driven mesenchyme production is further substantiated by increased expression of EMT-relevant genes including TGF?2, Has2, and periostin. Furthermore, we show that MEKK3 stimulates EMT via a TGF?2-dependent mechanism. Thus, the activity of MEKK3 is sufficient for developmental EMT in the heart. This knowledge provides a basis to understand how MEKK3 integrates signaling cascades activating endocardial cushion EMT.

Stevens, Mark V.; Broka, Derrick M.; Parker, Patti; Rogowitz, Elisa; Vaillancourt, Richard R.; Camenisch, Todd D.

2009-01-01

393

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

Microsoft Academic Search

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

Hamid Kh. Beheshti

2004-01-01

394

Patient safety during assistant propelled wheelchair transfers – The effect of the seat cushion on risk of falling  

Microsoft Academic Search

This paper is a report of a study of the effect of the seat cushion on risk of falling from a wheelchair. Two laboratory studies and simulated assistant propelled wheelchair transfers were conducted with four healthy female participants. For the laboratory studies there were three independent variables – trunk posture (upright\\/flexed forward), seat cushion (flat polyurethane\\/propad low profile), and feet

Olanrewaju O. Okunribido

2012-01-01

395

Biomechanical response to systematic changes in impact interface cushioning properties while performing a tennis-specific movement  

Microsoft Academic Search

It is currently not known whether human responses across typical sports surfaces are dependent on cushioning or frictional properties of the interface. The present study assessed systematic changes in surface cushioning (baseline acrylic, rubber, thin foam, and thick foam) as participants performed tennis running forehand foot plants wearing a basic neutral shoe (plimsolls). It was hypothesized that systematic decreases in

Victoria Stiles; Sharon Dixon

2007-01-01

396

Effect of seat cushion on dynamic stability in sitting during a reaching task in wheelchair users with paraplegia  

Microsoft Academic Search

Aissaoui R, Boucher C, Bourbonnais D, Lacoste M, Dansereau J. Effect of seat cushion on dynamic stability in sitting during a reaching task in wheelchair users with paraplegia. Arch Phys Med Rehabil 2001;82:274-81. Objectives: To examine the effects of seat cushions on dynamic stability in sitting during a controlled reaching task by wheelchair users with paraplegia. Design: A randomized, controlled

Rachid Aissaoui; Chantal Boucher; Daniel Bourbonnais; Michèle Lacoste; Jean Dansereau

2001-01-01

397

A COMPARISON OF THE CUSHIONING EFFECT OF THREE TOP RATED RUNNING SHOES AND A SHOE USING A NEW SPRING TECHNOLOGY  

Microsoft Academic Search

The purpose of this study was to compare the cushioning effect of three top rated running shoes and a new spring shoe technology. Shoes were mechanically dropped onto an AMTI force platform. The average in peak forces and the time to peak force were calculated to compare cushioning effect over multiple trials. The Nike and the Spira were found to

Mike Flores; Darla R. Smith

2004-01-01

398

A new weir surface repair layer with shock absorbing cushion design  

NASA Astrophysics Data System (ADS)

A shock absorbing cushion has never been introduced into any traditional weir surface repair layer design. However, shocks induced by high discharge with heavy sediment can easily produce brittle fracture and peeling over a weir surface repair layer as it is impacted by floods accompanied by particles of different sizes. In this study, transcending traditional designs, the authors developed a composite unit designed with a shock absorbing cushion that has performed well during field tests, proving that the weir body can be effectively protected even if the composite units are directly laid on a severely uneven weir surface repair layer.

Hsu, Tse-Shan; Hsieh, Yi-Lang

2013-09-01

399

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

SciTech Connect

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.

J. W. Schneider

2009-10-01

400

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

NASA Astrophysics Data System (ADS)

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.

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

401

Air toxics exposure from vehicle emissions at a U.S. border crossing: Buffalo Peace Bridge Study.  

PubMed

The Peace Bridge in Buffalo, New York, which spans the Niagara River at the east end of Lake Erie, is one of the busiest U.S. border crossings. The Peace Bridge plaza on the U.S. side is a complex of roads, customs inspection areas, passport control areas, and duty-free shops. On average 5000 heavy-duty diesel trucks and 20,000 passenger cars traverse the border daily, making the plaza area a potential "hot spot" for emissions from mobile sources. In a series of winter and summer field campaigns, we measured air pollutants, including many compounds considered by the U.S. Environmental Protection Agency (EPA*) as mobile-source air toxics (MSATs), at three fixed sampling sites: on the shore of Lake Erie, approximately 500 m upwind (under predominant wind conditions) of the Peace Bridge plaza; immediately downwind of (adjacent to) the plaza; and 500 m farther downwind, into the community of west Buffalo. Pollutants sampled were particulate matter (PM) < or = 10 microm (PM10) and < or = 2.5 microm (PM2.5) in aerodynamic diameter, elemental carbon (EC), 28 elements, 25 volatile organic compounds (VOCs) including 3 carbonyls, 52 polycyclic aromatic hydrocarbons (PAHs), and 29 nitrogenated polycyclic aromatic hydrocarbons (NPAHs). Spatial patterns of counts of ultrafine particles (UFPs, particles < 0.1 microm in aerodynamic diameter) and of particle-bound PAH (pPAH) concentrations were assessed by mobile monitoring in the neighborhood adjacent to the Peace Bridge plaza using portable instruments and Global Positioning System (GPS) tracking. The study was designed to assess differences in upwind and downwind concentrations of MSATs, in areas near the Peace Bridge plaza on the U.S. side of the border. The Buffalo Peace Bridge Study featured good access to monitoring locations proximate to the plaza and in the community, which are downwind with the dominant winds from the direction of Lake Erie and southern Ontario. Samples from the lakeside Great Lakes Center (GLC), which is upwind of the plaza with dominant winds, were used to characterize contaminants in regional air masses. On-site meteorologic measurements and hourly truck and car counts were used to assess the role of traffic on UFP counts and pPAH concentrations. The array of parallel and perpendicular residential streets adjacent to the plaza provided a grid on which to plot the spatial patterns of UFP counts and pPAH concentrations to determine the extent to which traffic emissions from the Peace Bridge plaza might extend into the neighboring community. For lake-wind conditions (southwest to northwest) 12-hour integrated daytime samples showed clear evidence that vehicle-related emissions at the Peace Bridge plaza were responsible for elevated downwind concentrations of PM2.5, EC, and benzene, toluene, ethylbenzene, and xylenes (BTEX), as well as 1,3-butadiene and styrene. The chlorinated VOCs and aldehydes were not differentially higher at the downwind site. Several metals (aluminum, calcium, iron, copper, and antimony) were two times higher at the site adjacent to the plaza as they were at the upwind GLC site on lake-wind sampling days. Other metals (beryllium, sodium, magnesium, potassium, titanium, manganese, cobalt, strontium, tin, cesium, and lanthanum) showed significant increases downwind as well. Sulfur, arsenic, selenium, and a few other elements appeared to be markers for regional transport as their upwind and downwind concentrations were correlated, with ratios near unity. Using positive matrix factorization (PMF), we identified the sources for PAHs at the three fixed sampling sites as regional, diesel, general vehicle, and asphalt volatilization. Diesel exhaust at the Peace Bridge plaza accounted for approximately 30% of the PAHs. The NPAH sources were identified as nitrate (NO3) radical reactions, diesel, and mixed sources. Diesel exhaust at the Peace Bridge plaza accounted for 18% of the NPAHs. Further evidence for the impact of the Peace Bridge plaza on local air quality was found when the differences in 10-minute average UFP counts and

Spengler, John; Lwebuga-Mukasa, Jamson; Vallarino, Jose; Melly, Steve; Chillrud, Steve; Baker, Joel; Minegishi, Taeko

2011-07-01

402

A VIBRATIONAL MODEL OF OPEN CELLED POLYURETHANE FOAM AUTOMOTIVE SEAT CUSHIONS  

Microsoft Academic Search

A mechanistic model of a seat cushion is developed. The work relates the kinematic motion of the seat to the geometric and constitutive properties of the cellular foam used in the seat. The model includes the influence of pneumatic damping caused by friction between the gas within the open-celled foam and matrix polymer. A continuous shape function is introduced to

W. N. Patten; S. Sha; C. Mo

1998-01-01

403

Whole-body vibration during manual wheelchair propulsion with selected seat cushions and back supports  

Microsoft Academic Search

Although the exposure to whole-body vibrations (WBV) has been shown to be detrimental to seated humans, the effects of wheelchairs and seating systems on the transmission of vibration to an individual have not been thoroughly examined. The purpose of this study was to determine if the selected wheelchair seat cushions and back supports minimize the transmission of vibrations. Thirty-two wheelchair

Carmen P. DiGiovine; Rory A. Cooper; Shirley G. Fitzgerald; Michael L. Boninger; Erik J. Wolf; Songfeng Guo

2003-01-01

404

A simplified test methodology for crashworthiness evaluation of aircraft seat cushions  

Microsoft Academic Search

The main subsystems of an aircraft involved in crashworthiness are the seat cushion, which is part of the seat structure, as well as the restraints, fuselage, and landing gear. A crashworthy structure is designed so that in the event of a crash, it will absorb impact energy in a controlled manner. All energy absorption materials such as honeycombs, polyurethane foams,

H KH Beheshti; H. M. Lankarani

2006-01-01

405

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

Code of Federal Regulations, 2013 CFR

...of Textiles; (iv) ASTM D3574-91âStandard Test Methods for Flexible Cellular MaterialsâSlab, Bonded, and Molded Urethane Foams; (v) ASTM D3676-78âStandard Specification for Rubber Cellular Cushion Used for Carpet or Rug...

2013-04-01

406

7 CFR 1785.70 - Application of RETRF cushion of credit payments.  

Code of Federal Regulations, 2013 CFR

...maintained an advance payment account with RUS...prior to using any balance remaining in its advance payment account to pay...borrower may reduce the balance of its cushion of credit...used to make scheduled payments on loans made or...

2013-01-01

407

Evaluation of Polyimide Foam as a Fire Barrier for Spacecraft Cushion Materials  

Microsoft Academic Search

Polyimide foam is an intrinsically flame resistant foam material. This study uses the NASA upward flame propagation test and the cone calorimeter test to evaluate the application of polyimide foam as a fire barrier for spacecraft cushion materials. The flame propagation test results demonstrate that a thin-layer of polyimide foam (3-mm thick) could totally stop the flame spread on the

F.-Y. Hshieh; D. Hirsch; H. Beeson

2003-01-01

408

Temperature Sensitive Dynamic Cushioning Function Development and Validation for BLOCKSOM Rubberized Hair.  

National Technical Information Service (NTIS)

After acquisition of drop test data on the cushioning performance of Type V Rubberized Hair, an Analysis of Variance (ANOVA) was conducted which was based upon the split-split plot experimental design to establish the statistical significance of the tempe...

R. M. Wyskida M. R. Wilhelm J. D. Bynum

1975-01-01

409

Clean Cities ozone air quality attainment and maintenance strategies that employ alternative fuel vehicles, with special emphasis on natural gas and propane  

SciTech Connect

Air quality administrators across the nation are coming under greater pressure to find new strategies for further reducing automotive generated non-methane hydrocarbon (NMHC) and nitrogen oxide (NOx) emissions. The US Environmental Protection Agency (EPA) has established stringent emission reduction requirements for ozone non-attainment areas that have driven the vehicle industry to engineer vehicles meeting dramatically tightened standards. This paper describes an interim method for including alternative-fueled vehicles (AFVs) in the mix of strategies to achieve local and regional improvements in ozone air quality. This method could be used until EPA can develop the Mobile series of emissions estimation models to include AFVs and until such time that detailed work on AFV emissions totals by air quality planners and emissions inventory builders is warranted. The paper first describes the challenges confronting almost every effort to include AFVs in targeted emissions reduction programs, but points out that within these challenges resides an opportunity. Next, it discusses some basic relationships in the formation of ambient ozone from precursor emissions. It then describes several of the salient provisions of EPA`s new voluntary emissions initiative, which is called the Voluntary Mobile Source Emissions Reduction Program (VMEP). Recent emissions test data comparing gaseous-fuel light-duty AFVs with their gasoline-fueled counterparts is examined to estimate percent emissions reductions achievable with CNG and LPG vehicles. Examples of calculated MOBILE5b emission rates that would be used for summer ozone season planning purposes by an individual Air Quality Control Region (AQCR) are provided. A method is suggested for employing these data to compute appropriate voluntary emission reduction credits where such (lighter) AFVs would be acquired. It also points out, but does not quantify, the substantial reduction credits potentially achievable by substituting gaseous-fueled for gasoline-fueled heavy-duty vehicles. Finally, it raises and expands on the relevance of AFVs and their deployment to some other provisions embedded in EPA`s current guidance for implementing 1-hour NAAQS--standards which currently remain in effect--as tools to provide immediate reductions in ozone, without waiting for promised future clean technologies.

Santini, D.J.; Saricks, C.L.

1998-08-04

410

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

PubMed

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

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

2002-10-01

411

Assessing air quality inside vehicles and at filling stations by monitoring benzene, toluene, ethylbenzene and xylenes with the use of semipermeable devices.  

PubMed

BTEX (benzene, toluene, ethylbenzene, and xylenes) were used as target molecules to evaluate the quality of air inside motor vehicles and near filling stations, using semipermeable membrane devices (SPMDs) as low-cost passive sampling devices. A direct, fast, simple methodology based on the use of headspace-gas chromatography-mass spectrometry detection (HS-GC-MS) was developed for BTEX determinations, without any sample pre-treatment. SPMDs (25.4 cm2 surface, filled with 100 microL triolein) were employed as static samplers. After the selected deployment time, the SPMDs were heated inside a HS vial at 150 degrees C for 20 min and BTEX compounds were determined by GC-MS in selected ion monitoring (SIM) mode in less than 12 min. The proposed method provides limits of detection of less than 1 ng SPMD(-1) for all compounds studied; which is equivalent to 0.3-8 ng m(-3) in air for a deployment time of 24 h, and to 9-200 microg m(-3) for 10 min time, as a function of the compound considered. Using sampling times of around 24 h, concentrations from 0.2 to 145 microg m(-3) were measured inside motor vehicles. For exposure times from 2 to 40 min, concentrations of BTEX ranging from 0.03 to 79 mg m(-3) were measured at filling stations, especially during refueling of vehicles with gasoline. PMID:17531831

Esteve-Turrillas, Francesc A; Pastor, Agustín; de la Guardia, Miguel

2007-05-03

412

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...

413

Maglev Vehicles and Superconductor Technology: Integration of High-Speed Ground Transportation into the Air Travel System.  

National Technical Information Service (NTIS)

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 resea...

L. R. Johnson D. M. Rote J. R. Hull H. T. Coffey J. G. Daley

1989-01-01

414

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

Microsoft Academic Search

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

R. Poola; K. Stork

1998-01-01

415

Demonstration of zinc/air fuel battery to enhance the range and mission of fleet electric vehicles: Preliminary results in the refueling of a multicell module  

SciTech Connect

We report progress in an effort to develop and demonstrate a refuelable zinc/air battery for fleet electric vehicle applications. A refuelable module consisting of twelve bipolar cells with internal flow system has been refueled at rates of nearly 4 cells per minute refueling time of 10 minutes for a 15 kW, 55 kWh battery. The module is refueled by entrainment of 0.5-mm particles in rapidly flowing electrolyte, which delivers the particles into hoppers above each cell in a parallel-flow hydraulic circuit. The concept of user-recovery is presented as an alternative to centralized service infrastructure during market entry.

Cooper, J.F.; Fleming, D.; Keene, L.; Maimoni, A.; Peterman, K.; Koopman, R.

1994-08-08

416

Membrane-Based Air Composition Control for Light-Duty Diesel Vehicles: A Benefit and Cost Assessment  

SciTech Connect

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 (PM{sub 2.5}). 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.

K. Stork; R. Poola

1998-10-01

417

Influence of entrapped air pockets on hydraulic transients in water pipelines  

Microsoft Academic Search

The pressure variations associated with a filling undulating pipeline containing an entrapped air pocket are investigated both experimentally and numerically. The influence of entrapped air on abnormal transient pressures is often ambiguous since the compressibility of the air pocket permits the liquid flow to accelerate but also partly cushions the system, with the balance of these tendencies being associated with

Ling Zhou; Deyou Liu; Byran W. Karney

2011-01-01

418

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

PubMed Central

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.

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

2012-01-01

419

MULTI-AXIS VIBRATION MITIGATION PROPERTIES OF SEAT CUSHIONS DURING MILITARY PROPELLER AIRCRAFT OPERATIONAL EXPOSURES  

Microsoft Academic Search

There have been increasing complaints of annoyance, fatigue, and musculoskeletal pain during prolonged exposures to propulsion-generated vibration in military propeller aircraft. The objective of this study was to evaluate the effects of seat cushions on mitigating the higher frequency (>10 Hz) multi-axis vibration associated with Navy E-2C Hawkeye operations. An E- 2C crew seat was used in the laboratory during

S. D. Smith; J. A. Smith

420

An investigation in crashworthiness evaluation of aircraft seat cushions at extreme ranges of temperature  

Microsoft Academic Search

This paper obtains a Mathematical Dynamic Model (MADYMO) for occupant lumbar load evaluation under CFR Part 23 and 25 at extreme\\u000a ranges of temperature. The validation of results is performed by full scale sled test results. Aircraft industries are using\\u000a viscoelastic polyurethane foams as seat cushion. Visco-elastic foams bring not only more comfort to the passengers in long\\u000a term sitting

Hamid Khademhosseini Beheshti; Hamid Lankarani

2010-01-01

421

Running in new and worn shoes: a comparison of three types of cushioning footwear  

Microsoft Academic Search

Objectives:In this study, the effect of shoe degradation on running biomechanics by comparing the kinetics and kinematics of running in new and worn shoes was investigated. Three types of footwear using different cushioning technologies were compared.Design:Longitudinal study.Setting:Pre- and post-tests on overground running at 4.5 m s?1 on a 20-m laboratory runway; performance measured using a force platform and a motion

P W Kong; N G Candelaria; D R Smith

2009-01-01

422

Effect of shoe cushioning on the development of reticulocytosis in distance runners  

Microsoft Academic Search

We studied erythropoietic activity in relation to the rearfoot cushioning of shoes worn by 14 male runners before, during, and the morning after a 17-day period of increased training mileage. The percentage of retic ulocytes in the red blood cell count (normal, <0.8%) served as the marker for erythropoietic activity. Each runner was assigned to either a firm-sole group (7)

Rudolph H. Dressendorfer; Charles E. Wade; Edward C. Frederick

1992-01-01

423

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

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.

2012-01-01

424

Wax beads as cushioning agents during the compression of coated diltiazem pellets.  

PubMed

Placebo particles were mixed with film-coated diltiazem pellets to evaluate them as cushioning agents during tabletting in order to protect the film coat from damage. The cushioning properties of alpha-lactose monohydrate granules, microcrystalline cellulose pellets and wax/starch beads were evaluated by comparing the dissolution profile of the coated pellets before and after compression (compression force 10 kN). Only the tablet formulations containing wax/starch beads provided protection to the film coat. However, the dissolution rate of tablets formulated with waxy maltodextrin/paraffinic wax placebo beads was too slow as the tablets did not disintegrate. Adding 50% (w/w) drum-dried corn starch/Explotab/paraffinic wax beads to the formulation was the optimal amount of cushioning beads to provide sufficient protection for the film coat and yield disintegrating tablets. Using a compression simulator, the effect of precompression force and compression time on the dissolution rate was found to be insignificant. The diametral crushing strength of tablets containing 50% (w/w) drum-dried corn starch/Explotab/paraffinic wax beads was about 25.0 N (+/-0.3 N), with a friability of 0.4% (+/-0.04%). This study demonstrates that adding deformable wax pellets minimizes the damage to film-coated pellets during compression. PMID:12393142

Vergote, G J; Kiekens, F; Vervaet, C; Remon, J P

2002-11-01

425

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

SciTech Connect

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.

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

1994-05-01

426

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

SciTech Connect

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.

None

2009-12-21

427

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

NASA Astrophysics Data System (ADS)

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 absorbing the energy during the impact. All the seats and seat cushions have to pass regulations defined by Federal Aviation Administration (FAA). In fact, all airplane companies are required to certify the subcomponents of aircrafts before installing them on the main structure, fuselage. Current Federal Aviation Administration Regulations require a dynamic sled test of the entire seat system for certifying the seat cushions. This dynamic testing is required also for replacing the deteriorated cushions with new cushions. This involves a costly and time-consuming certification process. AGATE group has suggested a procedure based on quasi-static testing in order to certify new seat cushions without conducting full-scale dynamic sled testing. AGATE subcomponent methodology involves static tests of the energy-absorbing foam cushions and design validation by conducting a full-scale dynamic seat test. Microscopic and macroscopic studies are necessary to provide a complete understanding about performance of foams during the crash. Much investigation has been done by different sources to obtain the reliable modeling in terms of demonstration of mechanical behavior of foams. However, rate sensitivity of foams needs more attention. A mathematical hybrid dynamic model for the cushion underneath of the human body will be taken into consideration in this research. Analytical and finite element codes such as MADYMO and LS-DYNA codes have the potential to greatly speed up the crashworthy design process, to help certify seats and aircraft to dynamic crash loads, to predict seat and occupant response to impact with the probability of injury, and to evaluate numerous crash scenarios not economically feasible with full-scale crash testing. Therefore, these codes are being used to find the accurate response of spinal load during the impact of model including human body, seat cushion and seat under different acceleration pulses. (Abstract shortened by UMI.)

Kh. Beheshti, Hamid

428

[Role of human olfaction in detection of space vehicle air contamination by gases emitted during thermal destruction of polymers].  

PubMed

The paper deals with the ability of human olfaction to identify odours associated with thermal destruction of polymers. The investigations confirmed the ability of early detection of equipment overheating and subjective odour evaluation using the 5-point intensity scale and calculating the relation of odour intensity to the maximum admissible concentration of volatile chemical contaminants aboard piloted space vehicles. Emission of gases by polymers in electrical equipment starts with heating temperature rise to 100 degrees C. A new odour smelled by only some of humans due to individual perception signifies typically that emitted gases are below MAC for space vehicle. Odour sensed by everyone though not irritating signifies, as a rule, of chemical contamination above MAC but not contingency. Symptoms of irritation by products of thermal destruction of polymers signify contingency and require the use of personal protection equipment. PMID:17405279

Solomin, G I; Mukhamedieva, L N; Nikitin, E I; Barantseva, M Iu

429

Transportation by Air-On the Ground  

NASA Astrophysics Data System (ADS)

A Rolair air flotation system is a spinoff of NASA/General Motors technology developed for the Apollo Program. It allows heavy loads to be moved easily by separating the load from the ground by a thin air cushion, virtually eliminating surface friction. Rolair Systems, Inc. was formed by former General Motors engineers and has successfully employed the system for both aerospace and nonaerospace industries.

1985-01-01

430

Computer Simulation of the Transient Response of a 4 Cylinder Stirling Engine with Burner and Air Preheater in a Vehicle.  

National Technical Information Service (NTIS)

A series of computer programs are presented with full documentation which simulate the transient behavior of a modern 4 cylinder Siemens arrangement Stirling engine with burner and air preheater. Cold start, cranking, idling, acceleration through 3 gear c...

W. R. Martini

1981-01-01

431

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)

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.

Orlowski, Christopher T.

432

Tracked-Vehicle Transportability.  

National Technical Information Service (NTIS)

This document describes the procedures for evaluating the transportability characteristics of tracked vehicles moving under their own power, or moved by carrier over highway, off-road terrain, rail, water, or by air. Keywords: Crane, Dynamometer, Lifting ...

1987-01-01

433

Crystallization Behavior of M97 Series Silicone Cushions  

SciTech Connect

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.

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

2000-09-07

434

H.R. 476: A Bill to amend the Clean Air Act to repeal certain emissions standards for motor vehicles which have not yet taken effect. Introduced in the House of Representatives, One Hundred Fourth Congress, First session  

SciTech Connect

This document contains H.R. 476, A Bill to amend the Clean Air Act to repeal certain emissions standards for motor vehicles which have not yet taken effect. This Bill was introduced in the House of Representatives, 104th Congress, First Session, January 11, 1995.

NONE

1995-12-31

435

Suggested Methods for Implementation of Life Cycle Costing Techniques in the Procurement of Air Force General Purpose Commercial Vehicles.  

National Technical Information Service (NTIS)

With decreasing Department of Defense budgets it is becoming more important to cut procurement cost and at the same time receive more for the money spent. One procurement method with this capability is Life Cycle Costing (LCC). Since vast sums of Air Forc...

E. R. Karsten L. T. McDaniel

1974-01-01

436

Analytical characterization of some components used in cellular silicon cushions: round-robin results  

SciTech Connect

The analytical characterization of a polysiloxane gum, General Electric's SE-54, has been completed in a round-robin fashion between Lawrence Livermore National Laboratory and Bendix Corporation (Kansas City Division). Three lots of gum were analyzed for the following chemical and physical properties: volatiles, molecular weight, weight percent vinyl and weight percent phenyl. The net result was specifications and procedures to be used for material acceptance at Bendix. In addition, a preliminary characterization has been completed of the silica filler used in conjunction with the polysiloxane gum to make cellular silicone cushions.

Catalano, E.; Clarkson, J.E.; Cupps, J.

1983-01-01

437

Evaluation of Ikon-12 (trade name) refrigerant for motor vehicle air conditioning. Report for October 1995-June 1996  

SciTech Connect

The paper gives results of an evaluation of a proprietary refrigerant, Ikon-12, as an alternative to hydrofluorocarbon (HFC)-134a for automotive air conditioning. In preliminary tests, Ikon-12 was found to be compatible with a polyolester lubricant and engineering materials. Refrigeration capacity and efficiency for Ikon-12 compared favorably to those for HFC-134a. In a preliminary durability test, Ikon-12 refrigerant showed no significant chemical breakdown after extended operation with an elevated compresssor discharge temperature.

Jetter, J.J.; Smith, N.D.; Ratanaphruks, K.; Ng, M.S.; Tufts, M.W.

1997-09-01

438

Computer modeling studies of the impact of vehicle exhaust emission controls on photochemical air pollution formation in the United Kingdom  

SciTech Connect

Numerical simulation techniques are applied to the formation of photochemical air pollutants in the London region for numerous emissions. A realistic simulation is achieved for the production of ozone, peroxyacetyl nitrate, peroxyproprionyl nitrate, and sulfate aerosol during photochemical episodes. Hydrocarbon control appears to have greater potential than nitrogen oxide control in reducing secondary pollution formation in the London region. The results of this study require further investigation over a larger geographical area in England. (1 graph, 50 references, 5 tables)

Derwent, R.G.; Hov, O.

1980-11-01

439

Evaluation of Ikon-12 (trade name) refrigerant for motor vehicle air conditioning. Report for October 1995June 1996  

Microsoft Academic Search

The paper gives results of an evaluation of a proprietary refrigerant, Ikon-12, as an alternative to hydrofluorocarbon (HFC)-134a for automotive air conditioning. In preliminary tests, Ikon-12 was found to be compatible with a polyolester lubricant and engineering materials. Refrigeration capacity and efficiency for Ikon-12 compared favorably to those for HFC-134a. In a preliminary durability test, Ikon-12 refrigerant showed no significant

J. J. Jetter; N. D. Smith; K. Ratanaphruks; M. S. Ng; M. W. Tufts

1997-01-01

440

Kinematics and shoulder belt position of child rear seat passengers during vehicle maneuvers.  

PubMed

Head impact to the seat back has been identified as one important injury causation scenario for seat belt restrained, head-injured children and previous research highlighted vehicle maneuvers prior to impact as possible contributing factors. The aim was to quantify kinematics of child occupants during swerving maneuvers focusing on the child's lateral movement and seat belt position relative to the child's shoulder. A study was conducted on a closed-circuit test track with 16 children aged 4-12, restrained in the rear seat of a modern passenger vehicle. A professional driving instructor drove at 50 km/h making sharp turns in a repeatable fashion, resulting in inboard motion of the children. The children were exposed to two turns in each of two restraint systems. Shorter children were on a booster or highback booster cushion. The taller children were seated on a booster cushion or with only a lap and shoulder seat belt. Four film cameras were fixed in the vehicle monitoring the child. Vehicle data were also collected. The seat belt slipped off the shoulder in 1 of 5 turns, varying by age and restraint type. Among shorter children, the belt slipped off in a majority of turns when seated on a booster cushion while the belt remained on the shoulder when seated on the highback booster cushion. Among taller children, the shoulder belt moved far laterally on the shoulder in half of the turns. This data provides valuable knowledge on possible pre-impact postures of children as a result of vehicle swerving maneuvers for a variety of restraint systems. PMID:22105379

Bohman, Katarina; Stockman, Isabelle; Jakobsson, Lotta; Osvalder, Anna-Lisa; Bostrom, Ola; Arbogast, Kristy B

2011-01-01

441

Exposure to acid anhydrides in three resin and one cushioned flooring manufacturing plants.  

PubMed

Acid anhydrides are reactive organic chemicals of low molecular weight which cause occupational asthma. No previous research on the relationship between exposure to these chemicals and respiratory sensitization and development of occupational asthma has been reported. A retrospective cohort study was carried out in four factories (three alkyd resin factories and one cushioned flooring factory) to investigate the nature of exposure-response relationships for sensitization to phthalic anhydride (PA), trimellitic anhydride (TMA) and maleic anhydride (MA). This paper describes the results of full-shift and task-specific exposure measurements. Exposure to PA was low in relation to the Occupational Exposure Standard (OES). The highest full-shift PA exposures occurred among resin operators in the resin factory that used solid PA as compared to other resin factories where liquid PA was used. Arithmetic mean exposure levels to TMA and MA in the resin factories were well below their respective OESs. Short-term high exposures occurred during loading of acid anhydrides into the reactors and sampling and testing of the resin. Relatively high full-shift exposure to TMA occurred in the cushioned flooring factory, although no high peak exposures were detected. PMID:8526391

van Tongeren, M J; Barker, R D; Gardiner, K; Harris, J M; Venables, K M; Taylor, A J; Harrington, J M

1995-10-01

442

The effect of cushioning insoles on back and lower extremity pain in an industrial setting.  

PubMed

The purpose of this study was to examine the relationship between low back pain and lower extremity pain in a group of factory workers and determine the effect of cushioning insoles on low back pain and lower extremity pain. Data were gathered via questionnaire from 306 employees of an aircraft engine assembly factory. A subset of 40 workers who had reported significant levels of back or lower extremity pain were sampled for four consecutive 12-hour shifts wearing their normal footwear and then a week later for four consecutive shifts wearing cushioning insoles. High levels of low back pain and lower extremity pain were reported by workers on the plant floor, but low back pain was poorly correlated to lower extremity pain (r = 0.371). The effect of insoles on the subset of 40 workers was to lower low back pain by 38%, foot pain by 37%, and knee pain by 38% (p < .001). The reduction in low back pain, however, was not correlated to the reduction in lower extremity pain; workers reporting a decrease in low back pain differed from those reporting less lower extremity pain. [Workplace Health Saf 2013;61(10):451-457.]. PMID:24053218

Jefferson, John R

2013-09-23

443

[Grading of the functional sport shoe parameter "cushioning" and "forefoot flexibility" on running shoes].  

PubMed

On nearly every running event a heterogeneous structure of participants regarding body height and body weight can be observed. This study should figure out whether the running shoe manufacturers will consider this anthropometric variability. Moreover it should be investigated the runners needs based on different anthropometrics regarding preferred cushioning and forefoot flexibility properties. In order to check whether the running shoe manufacturers will apply a grading pattern, a dynamic material study with conventional running shoes in different sizes was conducted. In a second step a field study in Middle Europe and North America with 244 female and 227 male runners was organized. Every subject had to run and evaluate 7 different shoe modifications. Based on the material study it is to state, that the running shoe manufacturers currently do not consider a systematic grading of cushioning and forefoot flexibility properties. In contrast to this, the field study reveals the necessity to grade these properties. A shoe size dependent and a geographic grading concept are suggested. It is supposed, that the application of these grading concepts do not only provide a comfort improvement, but they also contribute to a reduction of joint loads of the lower extremities and consequently to a prevention of overuse injuries. PMID:16544212

Kleindienst, F I; Krabbe, B; Walther, M; Brüggemann, G-P

2006-03-01

444

Hybrid options for light-duty vehicles  

Microsoft Academic Search

Hybrid electric vehicles (HEVs) offer great promise in improving fuel economy. In this paper, we analyze why, how, and by how much vehicle hybridization can reduce energy consumption and improve fuel economy. Our analysis focuses on efficiency gains associated solely with vehicle hybridization. We do not consider such other measures as vehicle weight reduction or air- and tire-resistance reduction, because

F. An; F. Stodolsky; D. Santini

1999-01-01

445

A probabilistic and multi-objective conceptual design methodology for the evaluation of thermal management systems on air-breathing hypersonic vehicles  

NASA Astrophysics Data System (ADS)

This thesis addresses the challenges associated with thermal management systems (TMS) evaluation and selection in the conceptual design of hypersonic, air-breathing vehicles with sustained cruise. The proposed methodology identifies analysis tools and techniques which allow the proper investigation of the design space for various thermal management technologies. The design space exploration environment and alternative multi-objective decision making technique defined as Pareto-based Joint Probability Decision Making (PJPDM) is based on the approximation of 3-D Pareto frontiers and probabilistic technology effectiveness maps. These are generated through the evaluation of a Pareto Fitness function and Monte Carlo analysis. In contrast to Joint Probability Decision Making (JPDM), the proposed PJPDM technique does not require preemptive knowledge of weighting factors for competing objectives or goal constraints which can introduce bias into the final solution. Preemptive bias in a complex problem can degrade the overall capabilities of the final design. The implementation of PJPDM in this thesis eliminates the need for the numerical optimizer which is required with JPDM in order to improve upon a solution. In addition, a physics-based formulation is presented for the quantification of TMS safety effectiveness corresponding to debris impact/damage and how it can be applied towards risk mitigation. Lastly, a formulation loosely based on non-preemptive Goal Programming with equal weighted deviations is provided for the resolution of the inverse design space. This key step helps link vehicle capabilities to TMS technology subsystems in a top-down design approach. The methodology provides the designer more knowledge up front to help make proper engineering decisions and assumptions in the conceptual design phase regarding which technologies show greatest promise, and how to guide future technology research.

Ordaz, Irian

446

Magnitude and value of electric vehicle emissions reductions for six driving cycles in four US cities with varying air quality problems  

SciTech Connect

The emissions of logically competing mid-1990 gasoline vehicles (GVs) and electric vehicles (EVs) are estimated as if the vehicles were driven in the same pattern of driving. Six different driving cycles are evaluated, ranging in speed from 7 to 49 miles per hour (mph). These steps are repeated using specifics of fuel composition, electric power mix, and environmental conditions applicable to Chicago, Denver, Los Angeles, and New York in the month of July. The year 2000 emissions differences for each of four regulated pollutants - HC, CO, NO[sub x,] SO[sub x] - are estimated. CO[sub 2] emissions are also estimated. With use of EVs, HC and CO emissions are consistently lowered by 98% or more. CO[sub 2] emissions reductions are uniformly large at low speed, but variable at high speed. It is found that initially introduced EVs could achieve 100% emission reductions in Chicago by using off-peak power from nuclear power plants for EV electricity generation. Emissions reductions occur for all combinations in Los Angeles, and for most combinations in New York, excepting SO[sub x]. NO[sub x] emissions are reduced in all four cities. An avoided cost'' value for each regulated pollutant is estimated for each of the cities. The values for each city depend on severity of air quality violations. It is estimated that the emissions reduction value of EVs driven an average of one and one half hours per day in Los Angeles ranges from $1050 to $3,900; $590 to $2100 in New York; $270 to $1200 in Chicago, and $330 to $1250 in Denver (1989$). Assuming a range of about 100 miles in congested conditions with speeds of 10 mph or less, the estimates range from $3600 to $13300 for Los Angeles; $2004 to $7200 for New York; $930 to $2930 for Chicago; and $1120 to $4290 for Denver. Low estimates are obtained using EPA's draft Mobile5 model for GV emissions, high values by using California's EMFAC7EP-SCF1 model. The dollar value benefit estimates include no economic value.

Wang, Q. (California Univ., Davis, CA (United States)); Santini, D.L. (Argonne National Lab., IL (United States))

1992-01-01

447

Magnitude and value of electric vehicle emissions reductions for six driving cycles in four US cities with varying air quality problems  

SciTech Connect

The emissions of logically competing mid-1990 gasoline vehicles (GVs) and electric vehicles (EVs) are estimated as if the vehicles were driven in the same pattern of driving. Six different driving cycles are evaluated, ranging in speed from 7 to 49 miles per hour (mph). These steps are repeated using specifics of fuel composition, electric power mix, and environmental conditions applicable to Chicago, Denver, Los Angeles, and New York in the month of July. The year 2000 emissions differences for each of four regulated pollutants - HC, CO, NO{sub x,} SO{sub x} - are estimated. CO{sub 2} emissions are also estimated. With use of EVs, HC and CO emissions are consistently lowered by 98% or more. CO{sub 2} emissions reductions are uniformly large at low speed, but variable at high speed. It is found that initially introduced EVs could achieve 100% emission reductions in Chicago by using off-peak power from nuclear power plants for EV electricity generation. Emissions reductions occur for all combinations in Los Angeles, and for most combinations in New York, excepting SO{sub x}. NO{sub x} emissions are reduced in all four cities. An ``avoided cost`` value for each regulated pollutant is estimated for each of the cities. The values for each city depend on severity of air quality violations. It is estimated that the emissions reduction value of EVs driven an average of one and one half hours per day in Los Angeles ranges from $1050 to $3,900; $590 to $2100 in New York; $270 to $1200 in Chicago, and $330 to $1250 in Denver (1989$). Assuming a range of about 100 miles in congested conditions with speeds of 10 mph or less, the estimates range from $3600 to $13300 for Los Angeles; $2004 to $7200 for New York; $930 to $2930 for Chicago; and $1120 to $4290 for Denver. Low estimates are obtained using EPA`s draft Mobile5 model for GV emissions, high values by using California`s EMFAC7EP-SCF1 model. The dollar value benefit estimates include no economic value.

Wang, Q. [California Univ., Davis, CA (United States); Santini, D.L. [Argonne National Lab., IL (United States)

1992-12-31

448

Intake fractions of primary conserved air pollutants emitted from on-road vehicles in the United States  

NASA Astrophysics Data System (ADS)

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.

Lobscheid, Agnes B.; Nazaroff, William W.; Spears, Michael; Horvath, Arpad; McKone, Thomas E.

2012-12-01

449

Magnitude and value of electric vehicle emissions reductions for six driving cycles in four US cities with varying air quality problems.  

National Technical Information Service (NTIS)

The emissions of logically competing mid-1990 gasoline vehicles (GVs) and electric vehicles (EVs) are estimated as if the vehicles were driven in the same pattern of driving. Six different driving cycles are evaluated, ranging in speed from 7 to 49 miles ...

Q. Wang D. L. Santini

1992-01-01

450

5-Star Safety Ratings: 2011-Newer Vehicles  

MedlinePLUS

5-Star Safety Ratings 2011-Newer Vehicles 1990-2010 Vehicles Air Bags Child Safety at Parents Central Resources Rollover ... to the most frequently asked questions about 5-Star Safety Ratings. During the government shutdown, NHTSA's 5- ...

451

Effects of Die Shapes and Additives on the Physical and Mechanical Properties, and Cellular Structure of Biodegradable Cushioning Extruded Foams  

Microsoft Academic Search

Efforts are focused on the effects of operating parameters, i.e., die shapes (DS), PVA ratio (PR), and additives (AT), on the physical and mechanical properties of corn-PVA extrudates in this study. The cellular structure of biodegradable extruded foams are studied and the extrudates are evaluated as cushioning materials. The process variables are the operating conditions, DS (O, ?, &Dgr;, and

Wai-Bun Lui; Jinchyau Peng

2005-01-01

452

Metal-air battery assessment  

Microsoft Academic Search

The objective of this report is to evaluate the present technical status of the zinc-air, aluminum\\/air and iron\\/air batteries and assess their potential for use in an electric vehicle. In addition, this report will outline proposed research and development priorities for the successful development of metal-air batteries for electric vehicle application.

R. K. Sen; S. L. Vanvoorhees; T. Ferrel

1988-01-01

453

Metal-air battery assessment  

NASA Astrophysics Data System (ADS)

The objective of this report is to evaluate the present technical status of the zinc-air, aluminum/air and iron/air batteries and assess their potential for use in an electric vehicle. In addition, this report will outline proposed research and development priorities for the successful development of metal-air batteries for electric vehicle application.

Sen, R. K.; Vanvoorhees, S. L.; Ferrel, T.

1988-05-01

454

Comparison of cotton and acrylic socks using a generic cushion sole design for runners.  

PubMed

A longitudinal single-blind study was conducted to test the friction blister prevention properties of synthetic acrylic socks in a generic construction. This study serves as a comparison with the authors' previous work comparing acrylic and cotton socks in a patented padded construction. Twenty-seven long-distance runners provided data regarding dampness, temperature, friction blister incidence, severity, and size. Two different socks were tested; each was identical in every aspect of construction except the fiber content. One test sock was composed of 100% synthetic acrylic fibers, and the other was composed of 100% natural cotton fibers. These results were unsuccessful at demonstrating any superiority of cotton or acrylic fibers when knitting produced a generic "cushion sole" sock. The superiority of acrylic fibers has thus far been demonstrated only when sock knitting provides adequate anatomical padding [corrected]. PMID:8289142

Herring, K M; Richie, D H

1993-09-01

455

Case for electric vehicles  

SciTech Connect

Cars that rely on electricity, not burning fuel, for motive power may offer the only workable solution to the joint predicaments of a global greenhouse effect and severe air pollution in cities. Much of the technology needed for building effective electric vehicles exists now or is under development. The emergence of electric vehicles has important economic implications. Whoever pioneers the commercialization of cost-competitive electric vehicle technologies will find inviting export markets around the world. Electric vehicles will be attractive where pollution is severe and intractable, peak vehicle performance is less highly valued than reliability and low maintenance, cheap electricity is available off-peak, and investments in oil distribution are small. Indeed, if the U.S. and other major industrial nations do not act, it is quite possible that the next generation of corporate automotive giants may arise in developing countries, where cars are relatively scarce today. This paper discusses the issues involved.

Sperling, D. [Univ. of California, Davis, CA (United States)

1996-11-01

456

Design, modelling, implementation, and intelligent fuzzy control of a hovercraft  

Microsoft Academic Search

A Hovercraft is an amphibious vehicle that hovers just above the ground or water by air cushion. The concept of air cushion vehicle can be traced back to 1719. However, the practical form of hovercraft nowadays is traced back to 1955. The objective of the paper is to design, simulate and implement an autonomous model of a small hovercraft equipped

M. M. El-Khatib; W. M. Hussein

2011-01-01

457

Highways and Air Quality.  

National Technical Information Service (NTIS)

Recognizing the significant contribution of motor vehicles to air pollution in a number of urban areas, the Congress enacted the Clean Air Amendments of 1970 (84 Stat. 1676) that require substantial reductions in carbon monoxide and hydrocarbon emissions ...

1973-01-01

458

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)

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).

Collins, Gaemus E.; Vegdahl, Philip S.; Riehl, James R.

2007-05-01

459

Aluminum-Air Battery for Automotive Propulsion.  

National Technical Information Service (NTIS)

Research on the development of aluminum-air batteries which will be used in energy efficient, economical electric vehicles is reviewed with information on the research strategy, performance characteristics of aluminum-air cells, vehicle design, and the ne...

J. F. Cooper E. Behrin

1980-01-01

460

Air Vehicle Integration and Technology Research (AVIATR). Task Order 0023: Predictive Capability for Hypersonic Structural Response and Life Prediction: Phase 2 - Detailed Design of Hypersonic Cruise Vehicle Hot- Structure.  

National Technical Information Service (NTIS)

Four panels from a representative Mach 7 hypersonic cruise vehicle were designed and analyzed with state-of-the-art standard methods and tools to verify structural response and life predictive capabilities. Several modifications were made to the Technolog...

G. Tzong J. Embler R. Jacobs R. Quiroz S. Liguore

2012-01-01

461

Method of Determining Watertight Integrity in Hovercraft.  

National Technical Information Service (NTIS)

The patent application relates to a method of determining the watertight integrity of the floatation hull of air cushion vehicles, ground effect machines, and hovercraft by measuring the differential air pressure between the air pressure in the hull or in...

B. Sharrow K. C. Hoerman J. W. Cauanaugh

1974-01-01

462

Testing the stress-gradient hypothesis at the roof of the world: effects of the cushion plant Thylacospermum caespitosum on species assemblages.  

PubMed

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

Dvorský, Miroslav; Doležal, Ji?í; Kopecký, Martin; Chlumská, Zuzana; Janatková, Kate?ina; Altman, Jan; de Bello, Francesco; ?eháková, Klára

2013-01-10

463

Compensatory adjustments in lower extremity kinematics in response to a reduced cushioning of the impact interface in heel–toe running  

Microsoft Academic Search

The response of heel-toe runners to changes in cushioning of the impact interface was investigated. Ground reaction force\\u000a and sagittal plane kinematic data were collected for six heel-toe runners performing barefoot running trials on a conventional\\u000a asphalt surface and an asphalt surface with additional cushioning. Statistical analysis indicated that similar peak impact\\u000a force values were maintained when running on the

S. J. Dixon; A. C. Collop; M. E. Batt

2005-01-01

464

Design and preliminary evaluation of an air-alternating wheelchair seating system for pressure ulcer prevention  

Microsoft Academic Search

Despite the diversity of wheelchair cushions currently used and reported, pressure on bony prominences continues to be a major problem for wheelchair-bound patients, and the incidence of pressure ulcers remains high. This paper introduces a novel air-alternating wheelchair seating (AWS) system for pressure ulcer prevention. The AWS system is composed of 9 separate air chambers, an air pressure sensor MPX2202

Yuxiang Yang; Jian Wang; Zonghai Gao; Yi Zhou

2010-01-01

465

Measurement and modelling of x-direction apparent mass of the seated human body–cushioned seat system  

Microsoft Academic Search

For modelling purposes and for evaluation of driver's seat performance in the vertical direction various mechano-mathematical models of the seated human body have been developed and standardized by the ISO. No such models exist hitherto for human body sitting in an upright position in a cushioned seat upper part, used in industrial environment, where the fore-and-aft vibrations play an important

George Juraj Stein; Peter Mú?ka; Rudolf Chmúrny; Barbara Hinz; Ralph Blüthner

2007-01-01

466

Loss of muscleblind-like 1 promotes invasive mesenchyme formation in endocardial cushions by stimulating autocrine TGF?3  

PubMed Central

Background Valvulogenesis and septation in the developing heart depend on the formation and remodeling of endocardial cushions in the atrioventricular canal (AVC) and outflow tract (OFT). These cushions are invaded by a subpopulation of endocardial cells that undergo an epithelial-mesenchymal transition in response to paracrine and autocrine transforming growth factor ? (TGF?) signals. We previously demonstrated that the RNA binding protein muscleblind-like 1 (MBNL1) is expressed specifically in the cushion endocardium, and knockdown of MBNL1 in stage 14 embryonic chicken AVC explants enhances TGF?-dependent endocardial cell invasion. Results In this study, we demonstrate that the effect of MBNL1 knockdown on invasion remains dependent on TGF?3 after it is no longer required to induce basal levels of invasion. TGF?3, but not TGF?2, levels are elevated in medium conditioned by MBNL1-depleted AVC explants. TGF?3 is elevated even when the myocardium is removed, indicating that MBNL1 modulates autocrine TGF?3 production in the endocardium. More TGF?3-positive cells are observed in the endocardial monolayer following MBNL1 knockdown. Addition of exogenous TGF?3 to AVC explants recapitulates the effects of MBNL1 knockdown. Time course experiments demonstrate that knockdown of MBNL1 induces precocious TGF?3 secretion, and early exposure to excess TGF?3 induces precocious invasion. MBNL1 expression precedes TGF?3 in the AVC endocardium, consistent with a role in preventing precocious autocrine TGF?3 signaling. The stimulatory effects of MBNL1 knockdown on invasion are lost in stage 16 AVC explants. Knockdown of MBNL1 in OFT explants similarly enhances cell invasion, but not activation. TGF? is necessary and sufficient to mediate this effect. Conclusions Taken together, these data support a model in which MBNL1 negatively regulates cell invasion in the endocardial cushions by restricting the magnitude and timing of endocardial-derived TGF?3 production.

2012-01-01

467

A two-dimensional zeolitic imidazolate framework with a cushion-shaped cavity for CO2 adsorption.  

PubMed

A new two-dimensional zeolitic imidazolate framework (named as ZIF-L) was synthesized in zinc salt and 2-methylimidazole (Hmim) aqueous solution at room temperature. ZIF-L (Zn(mim)2·(Hmim)1/2·(H2O)3/2 or C10H16N5O3/2Zn) has unique cushion-shaped cavities and leaf-like crystal morphology, and exhibits excellent CO2 adsorption properties. PMID:24018656

Chen, Rizhi; Yao, Jianfeng; Gu, Qinfen; Smeets, Stef; Baerlocher, Christian; Gu, Haoxue; Zhu, Dunru; Morris, William; Yaghi, Omar M; Wang, Huanting

2013-10-21

468

Aerodynamics for Revolutionary Air Vehicles.  

National Technical Information Service (NTIS)

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. Bre...

W. L. Sellers B. A. Singer L. D. Leavitt

2003-01-01

469

Sulfate Emissions from Vehicles on the Road  

Microsoft Academic Search

Experiments have been conducted to measure vehicle sulfate emissions, by vehicle type, at two tunnels on the Pennsylvania Turnpike. A satisfactory balance between estimated fuel sulfur consumption and observed emissions of sulfur compounds corrected for ambient-air contributions was obtained. This work started in 1974 before the introduction of catalyst-equipped automobiles and continued into 1976. The sulfate contributed by vehicles even

W. R. Pierson; W. W. Brachaczek; R. H. Hammerle; D. E. McKee; J. W. Butler

1978-01-01

470

Air Quality Management in Mexico  

Microsoft Academic Search

Several significant program and policy measures have been implemented in Mexico over the past 15 yr to improve air quality. This article provides an overview of air quality management strategies in Mexico, including (1) policy initiatives such as vehicle use restrictions, air quality standards, vehicle emissions, and fuel quality standards, and (2) supporting programs including establishment of a national emission

Adrián Fernández-Bremauntz

2008-01-01

471

The use of inert gas as cushion gas in underground storage  

SciTech Connect

In early 1989 there were 395 underground natural gas storage fields in the United States operated by both transmission and distribution companies as an integral part of the gas industry`s delivery system. Base (cushion) gas is required to maintain storage reservoir volume and pressure to ensure adequate deliverability. Base gas is a major investment cost for new storage field development. An inert gas, such as nitrogen, that is less expensive than natural gas can be used to fill all or part of the base gas requirement and yield significant savings in the cost of storage field development. Inert base gas use, tested originally in France, should not dilute the pipeline quality of natural gas withdrawn from storage. The key technical issue is the degree to which natural and inert gases mix in the storage reservoir. The nature of the rock pore spaces that comprise storage fields inhibits the mixing process. A systematic planning approach has been developed to ensure that there are no long-term operating problems with storage fields containing inert base gas. The first field test of inert base gas technology in the US is being planned. The use of inert base gas is a promising technique with the potential to significantly reduce storage investment costs.

Randolph, P.L.; Foh, S.E.

1992-12-31

472

Endothelial SUR-8 Acts in an ERK-Independent Pathway During Atrioventricular Cushion Development  

PubMed Central

SUR-8, a conserved leucine-rich repeats protein, was first identified as a positive regulator of Ras pathway in Caenorhabditis elegans. Biochemical studies indicated that SUR-8 interacts with Ras and Raf, leading to the elevated ERK activity. However, the physiological role of SUR-8 during mammalian development remains unclear. Here we found that germline deletion of SUR-8 in mice resulted in early embryonic lethality. Inactivated SUR-8 specifically in mouse endothelial cells (ECs) revealed that SUR-8 is essential for embryonic heart development. SUR-8 deficiency in ECs resulted in late embryonic lethality, and the mutant mice displayed multiple cardiac defects. The reduced endothelial-mesenchymal transformation (EMT) and the reduced mesenchyme proliferation phase were observed in the atrioventricular canal (AVC) within the mutant hearts, leading to the formation of hypoplastic endocardial cushions. However, ERK activation did not appear to be affected in mutant ECs, suggesting that SUR-8 may act in an ERK-independent pathway to regulate AVC development. Developmental Dynamics 239:2005–2013, 2010 © 2010 Wiley-Liss, Inc.

Yi, Jing; Chen, Muyun; Wu, Xiaohui; Yang, Xiao; Xu, Tian; Zhuang, Yuan; Han, Min; Xu, Rener

2010-01-01

473

Emission control cost-effectiveness of alternative-fuel vehicles  

SciTech Connect

Although various legislation and regulations have been adopted to promote the use of alternative-fuel vehicles for curbing urban air pollution problems, there is a lack of systematic comparisons of emission control cost-effectiveness among various alternative-fuel vehicle types. In this paper, life-cycle emission reductions and life-cycle costs were estimated for passenger cars fueled with methanol, ethanol, liquefied petroleum gas, compressed natural gas, and electricity. Vehicle emission estimates included both exhaust and evaporative emissions for air pollutants of hydrocarbon, carbon monoxide, nitrogen oxides, and air-toxic pollutants of benzene, formaldehyde, 1,3-butadiene, and acetaldehyde. Vehicle life-cycle cost estimates accounted for vehicle purchase prices, vehicle life, fuel costs, and vehicle maintenance costs. Emission control cost-effectiveness presented in dollars per ton of emission reduction was calculated for each alternative-fuel vehicle types from the estimated vehicle life-cycle emission reductions and costs. Among various alternative-fuel vehicle types, compressed natural gas vehicles are the most cost-effective vehicle type in controlling vehicle emissions. Dedicated methanol vehicles are the next most cost-effective vehicle type. The cost-effectiveness of electric vehicles depends on improvements in electric vehicle battery technology. With low-cost, high-performance batteries, electric vehicles are more cost-effective than methanol, ethanol, and liquified petroleum gas vehicles.

Wang, Q. [Argonne National Lab., IL (United States); Sperling, D.; Olmstead, J. [California Univ., Davis, CA (United States). Inst. of Transportation Studies

1993-06-14

474

Lameness in dairy cattle: A debilitating disease or a disease of debilitated cattle? A cross-sectional study of lameness prevalence and thickness of the digital cushion.  

PubMed

Lameness is the most significant challenge for the dairy industry to overcome, given its obvious disruption of animal welfare and severe economic losses. Sole ulcers and white line abscesses are ubiquitous chronic diseases with the highest associated economic losses among all foot lesions. Their underlying causes are still not fully understood. An observational cross-sectional study was carried out to investigate the association between claw horn lesions and the thickness of the digital cushion.The thickness of the digital cushion was evaluated by ultrasonographic examination of the sole at the typical ulcer site. A total of 501 lactating Holstein dairy cows were enrolled in the study. The prevalence of sole ulcers was 4.2 and 27.8% for parity 1 and parity >1, respectively.The prevalence of white line disease was 1.0 and 6.5% for parity 1 and >1, respectively. The prevalence of lameness (visual locomotion score > or = 3) was 19.8 and 48.2% for parity 1 and >1, respectively. The prevalence of sole ulcers and white line diseases was significantly associated with thickness of the digital cushion; cows in the upper quartile of digital cushion thickness had an adjusted prevalence of lameness 15 percentage points lower than the lower quartile. Body condition scores were positively associated with digital cushion thickness.The mean gray value of the sonographic image of the digital cushion had a negative linear association with digital cushion thickness (R2 = 0.14), indicating that the composition of the digital cushion may have changed with its thickness. Furthermore, digital cushion thickness decreased steadily from the first month of lactation and reached a nadir 120 d after parturition.These results support the concept that sole ulcers and white line abscesses are related to contusions within the claw horn capsule and such contusions are a consequence of the lesser capacity of the digital cushion to dampen the pressure exerted by the third phalanx on the soft tissue beneath. PMID:19757545

Bicalho, R C; Machado, V S; Caixeta, L S

2009-07-01

475

40 CFR 88.104-94 - Clean-fuel vehicle tailpipe emission standards for light-duty vehicles and light-duty trucks.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Clean-fuel vehicle tailpipe emission standards for light-duty vehicles and light-duty trucks. 88.104-94...AIR PROGRAMS (CONTINUED) CLEAN-FUEL VEHICLES Emission Standards for Clean-Fuel...

2013-07-01

476

Vehicle Utilization.  

National Technical Information Service (NTIS)

In September 1966, a decision was made to go on a plant-wide pooling basis with no vehicles assigned to individuals. After investigation, it was decided that some of the vehicles formerly used as pools should be classified as functional. Pool vehicles are...

J. E. Harding

1976-01-01

477

Vehicle emissions and consumer information in car advertisements  

Microsoft Academic Search

BACKGROUND: The advertising of vehicles has been studied from a safety perspective but not in terms of vehicle air pollutants. We aimed to examine the content and trends of greenhouse gas emissions and air pollution-related information, in light passenger vehicle advertisements. METHODS: Content analysis of the two most popular current affairs magazines in New Zealand for the five year period

Nick Wilson; Anthony Maher; George Thomson; Michael Keall

2008-01-01

478

NC consumer views and market potential of electric vehicles  

Microsoft Academic Search

Electric vehicles offer the potential to reduce air pollution and lower petroleum use, if people will buy them. A random sample of 260 North Carolina households is asked about present vehicle ownership and use, opinions about electric vehicles, and likelihoo