Science.gov

Sample records for air control valve

  1. Controlled PCV valve

    SciTech Connect

    Zeigler, T.W. Jr.; Romanczuk, C.S.; Betterton, J.T.; Glover, A.H.

    1987-08-18

    A positive crankcase ventilation control device is described for use with an internal combustion engine and, specifically, for controlling the flow of emission laden vaporous fluids from the crankcase thereof, the control device including selective power means for substantially increasing the flow of emission laden air through the device, comprising: a generally hollow housing with an inlet forming portion adapted to be fluidly connected to the interior spaces of an internal combustion engine to receive emission laden air therefrom; the housing having an outlet forming device adapted to be fluidly connected to the air and fuel inletting portion of the internal combustion engine for disposing of the emission laden air from the engine, the inlet and outlet portions being connected within the interior of the housing by a flow control passage of specific flow area; an elongated valve plug member within the housing and having an end portion with a conically tapered configuration adapted to move progressively into the aforesaid flow control passage thereby decreasing the flow area thereof and, consequently, the total flow through the device; yieldable means urging the elongated valve member toward a position ensuring maximum flow through the flow control passage, but being yieldable to allow the valve member to move so that the conically tapered portion progressively extends further into the flow control passage to thereby decrease the flow area.

  2. Pressure control valve. [inflating flexible bladders

    NASA Technical Reports Server (NTRS)

    Lambson, K. H. (Inventor)

    1980-01-01

    A control valve is provided which is adapted to be connected between a pressure source, such as a vacuum pump, and a pressure vessel so as to control the pressure in the vessel. The valve comprises a housing having a longitudinal bore which is connected between the pump and vessel, and a transversely movable valve body which controls the air flow through an air inlet in the housing. The valve body includes cylindrical and conical shaped portions which cooperate with reciprocally shaped portions of the housing to provide flow control. A filter in the air inlet removes foreign matter from the air. The bottom end of the valve body is screwed into the valve housing control knob formed integrally with the valve body and controls translation of the valve body, and the opening and closing of the valve.

  3. Valve for fluid control

    SciTech Connect

    Oborny, Michael C.; Paul, Phillip H.; Hencken, Kenneth R.; Frye-Mason, Gregory C.; Manginell, Ronald P.

    2001-01-01

    A valve for controlling fluid flows. This valve, which includes both an actuation device and a valve body provides: the ability to incorporate both the actuation device and valve into a unitary structure that can be placed onto a microchip, the ability to generate higher actuation pressures and thus control higher fluid pressures than conventional microvalves, and a device that draws only microwatts of power. An electrokinetic pump that converts electric potential to hydraulic force is used to operate, or actuate, the valve.

  4. Overflow control valve

    DOEpatents

    Hundal, Rolv; Kessinger, Boyd A.; Parlak, Edward A.

    1984-07-24

    An overflow control valve for use in a liquid sodium coolant pump tank which valve can be extended to create a seal with the pump tank wall or retracted to break the seal thereby accommodating valve removal. An actuating shaft which controls valve disc position also has cams which bear on roller surfaces to force retraction of a sliding cylinder against spring tension to retract the cylinder from sealing contact with the pump tank.

  5. Intelligent Flow Control Valve

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R (Inventor)

    2015-01-01

    The present invention is an intelligent flow control valve which may be inserted into the flow coming out of a pipe and activated to provide a method to stop, measure, and meter flow coming from the open or possibly broken pipe. The intelligent flow control valve may be used to stop the flow while repairs are made. Once repairs have been made, the valve may be removed or used as a control valve to meter the amount of flow from inside the pipe. With the addition of instrumentation, the valve may also be used as a variable area flow meter and flow controller programmed based upon flowing conditions. With robotic additions, the valve may be configured to crawl into a desired pipe location, anchor itself, and activate flow control or metering remotely.

  6. Well valve control system

    SciTech Connect

    Schwendemann, K.L.; McCracken, O.W.; Mondon, C.G.; Wortham, L.C.

    1987-01-13

    A system is described for controlling well testing through an upper and lower test string with a subsea test tree connected therebetween and latch means to release the upper test string from the subsea test tree comprising: a. first and second selectively programmable microprocessor means; b. means for storing system operating limits in each microprocessor means; c. means for changing the operating limits in response to changes in well conditions; d. means for communicating operating fluid pressure to the subsurface test tree and the latch means; e. solenoid pilot valves controlling the flow of the operating fluid pressure to the subsea test tree and the latch means; f. the first microprocessor means located at a central control console; g. the second microprocessor means located near the solenoid valves; h. means for transmitting signals between the first and second microprocessor means and validating the accuracy of the signals; and i. electronic circuits to control operation of the solenoid valves in response to validated signals.

  7. Pressure compensated flow control valve

    DOEpatents

    Minteer, Daniel J.

    1999-01-01

    The invention is an air flow control valve which is capable of maintaining a constant flow at the outlet despite changes in the inlet or outlet pressure. The device consists of a shell assembly with an inlet chamber and outlet chamber separated by a separation plate. The chambers are connected by an orifice. Also located within the inlet chamber is a port controller assembly. The port controller assembly consists of a differential pressure plate and port cap affixed thereon. The cap is able to slide in and out of the orifice separating the inlet and outlet chambers. When the pressure differential is sufficient, the differential pressure plate rises or falls to maintain a constant air flow. Movement of the port controller assembly does not require the use of seals, diaphragms, tight tolerances, bushings, bearings, hinges, guides, or lubricants.

  8. Self Adaptive Air Turbine for Wave Energy Conversion Using Shutter Valve and OWC Heoght Control System

    SciTech Connect

    Di Bella, Francis A

    2014-09-29

    An oscillating water column (OWC) is one of the most technically viable options for converting wave energy into useful electric power. The OWC system uses the wave energy to “push or pull” air through a high-speed turbine, as illustrated in Figure 1. The turbine is typically a bi-directional turbine, such as a Wells turbine or an advanced Dennis-Auld turbine, as developed by Oceanlinx Ltd. (Oceanlinx), a major developer of OWC systems and a major collaborator with Concepts NREC (CN) in Phase II of this STTR effort. Prior to awarding the STTR to CN, work was underway by CN and Oceanlinx to produce a mechanical linkage mechanism that can be cost-effectively manufactured, and can articulate turbine blades to improve wave energy capture. The articulation is controlled by monitoring the chamber pressure. Funding has been made available from the U.S. Department of Energy (DOE) to CN (DOE DE-FG-08GO18171) to co-share the development of a blade articulation mechanism for the purpose of increasing energy recovery. However, articulating the blades is only one of the many effective design improvements that can be made to the composite subsystems that constitute the turbine generator system.

  9. Air flow through poppet valves

    NASA Technical Reports Server (NTRS)

    Lewis, G W; Nutting, E M

    1920-01-01

    Report discusses the comparative continuous flow characteristics of single and double poppet valves. The experimental data presented affords a direct comparison of valves, single and in pairs of different sizes, tested in a cylinder designed in accordance with current practice in aviation engines.

  10. Supplemental air valve for internal combustion engine

    SciTech Connect

    Pankow, C.W.

    1987-12-29

    A valve for attachment in the PCV system of an internal combustion engine for regulating the admission of supplemental air to the crank case blow-by return, comprising: (a) a valve body defining a bore, the body having an inlet and an outlet connection defining a passageway through the valve for the blow-by return, the body further defining a port for air; (b) a valve member reciprocal within the bore having a piston member dividing at least a portion of the bore into two pressure chambers, the pressure chambers having means for connection of each to a source of engine vacuum; (c) the valve member being shiftable from and open position permitting air to enter through the port to the passageway and having a closed position blocking admission of air through the port to the passageway; and (d) resilient means normally urging the valve body to the closed position, the resilient means being selectively adjustable to provide a predetermined biasing force whereby the piston is shiftable to the open position in response to changes in engine vacuum to admit supplemental air to the engine.

  11. Simulation of a Hydraulic Pump Control Valve

    NASA Technical Reports Server (NTRS)

    Molen, G. Vander; Akers, A.

    1987-01-01

    This paper describes the mode of operation of a control valve assembly that is used with a hydraulic pump. The operating system of the valve is modelled in a simplified form, and an analogy for hydraulic resonance of the pressure sensing system is presented. For the control valve investigated, air entrainment, length and diameter of the resonator neck, and valve mass produced the greatest shift in resonant frequency. Experimental work was conducted on the hydraulic system so that the resonance levels and frequencies could be measured and the accuracy of the theory verified. The results obtained make it possible to evaluate what changes to any of the variables considered would be most effective in driving the second harmonic frequency above the operating range.

  12. 9. BUTTERFLY VALVE CONTROL DIABLO POWERHOUSE. BUTTERFLY VALVES WERE MANUFACTURED ...

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

    9. BUTTERFLY VALVE CONTROL DIABLO POWERHOUSE. BUTTERFLY VALVES WERE MANUFACTURED BY THE PELTON WATER WHEEL COMPANY IN 1931, 1989. - Skagit Power Development, Diablo Powerhouse, On Skagit River, 6.1 miles upstream from Newhalem, Newhalem, Whatcom County, WA

  13. Pressure valve for needle gate valve control. June 13, 1913. ...

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

    Pressure valve for needle gate valve control. June 13, 1913. Photocopy of original drawing. Drawing on file at the Salt River Project Archives. Phoenix, Arizona - Cross Cut Hydro Plant, North Side of Salt River, Tempe, Maricopa County, AZ

  14. Cavitation guide for control valves

    SciTech Connect

    Tullis, J.P.

    1993-04-01

    This guide teaches the basic fundamentals of cavitation to provide the reader with an understanding of what causes cavitation, when it occurs, and the potential problems cavitation can cause to a valve and piping system. The document provides guidelines for understanding how to reduce the cavitation and/or select control valves for a cavitating system. The guide provides a method for predicting the cavitation intensity of control valves, and how the effect of cavitation on a system will vary with valve type, valve function, valve size, operating pressure, duration of operation and details of the piping installation. The guide defines six cavitation limits identifying cavitation intensities ranging from inception to the maximum intensity possible. The intensity of the cavitation at each limit Is described, including a brief discussion of how each level of cavitation influences the valve and system. Examples are included to demonstrate how to apply the method, including making both size and pressure scale effects corrections. Methods of controlling cavitation are discussed providing information on various techniques which can be used to design a new system or modify an existing one so it can operate at a desired level of cavitation.

  15. Ferroelectric Fluid Flow Control Valve

    NASA Technical Reports Server (NTRS)

    Jalink, Antony, Jr. (Inventor); Hellbaum, Richard F. (Inventor); Rohrbach, Wayne W. (Inventor)

    1999-01-01

    An active valve is controlled and driven by external electrical actuation of a ferroelectric actuator to provide for improved passage of the fluid during certain time periods and to provide positive closure of the valve during other time periods. The valve provides improved passage in the direction of flow and positive closure in the direction against the flow. The actuator is a dome shaped internally prestressed ferroelectric actuator having a curvature, said dome shaped actuator having a rim and an apex. and a dome height measured from a plane through said rim said apex that varies with an electric voltage applied between an inside and an outside surface of said dome shaped actuator.

  16. Valve for controlling solids flow

    DOEpatents

    Feldman, David K.

    1980-01-01

    A fluidized solids control valve is disclosed that is particularly well adapted for use with a flow of coal or char that includes both large particles and fines. The particles may or may not be fluidized at various times during the operation. The valve includes a tubular body that terminates in a valve seat covered by a normally closed closure plate. The valve body at the seat and the closure plate is provided with aligned longitudinal slots that receive a pivotally supported key plate. The key plate is positionable by an operator in inserted, intermediate and retracted positions respecting the longitudinal slot in the valve body. The key plate normally closes the slot within the closure plate but is shaped and aligned obliquely to the longitudinal slot within the valve body to provide progressively increasing slot openings between the inserted and retracted positions. Transfer members are provided between the operator, key plate and closure plate to move the closure plate into an open position only when the key plate is retracted from the longitudinal slot within the valve body.

  17. Diaphragms in air-operated valves

    SciTech Connect

    Groeger, J.E.

    1996-12-01

    The author will present current issues related to diaphgrams in air-operated valves. Altran Materials Engineering, Inc., often performs root-cause analyses for nuclear power plant owners. The author will discuss various analyses that have been performed or are currently underway.

  18. 30 CFR 56.14114 - Air valves for pneumatic equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Air valves for pneumatic equipment. 56.14114... Equipment Safety Devices and Maintenance Requirements § 56.14114 Air valves for pneumatic equipment. A manual master quick-close type air valve shall be installed on all pneumatic-powered equipment if...

  19. 30 CFR 56.14114 - Air valves for pneumatic equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Air valves for pneumatic equipment. 56.14114... Equipment Safety Devices and Maintenance Requirements § 56.14114 Air valves for pneumatic equipment. A manual master quick-close type air valve shall be installed on all pneumatic-powered equipment if...

  20. 30 CFR 57.14114 - Air valves for pneumatic equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Air valves for pneumatic equipment. 57.14114... and Equipment Safety Devices and Maintenance Requirements § 57.14114 Air valves for pneumatic equipment. A manual master quick-close type air valve shall be installed on all pneumatic-powered...

  1. 30 CFR 57.14114 - Air valves for pneumatic equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Air valves for pneumatic equipment. 57.14114... and Equipment Safety Devices and Maintenance Requirements § 57.14114 Air valves for pneumatic equipment. A manual master quick-close type air valve shall be installed on all pneumatic-powered...

  2. 25. Typical valves used to control flow into and out ...

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

    25. Typical valves used to control flow into and out of filtration bed. Left valve (painted red) drains the bed, and center valve (painted green) admits water into the bed. The right valve is a cross over valve which is used to admit water into a dry bed from the bottom. This bottom fill excludes entrapped air as the bed is filled. When the water reached to top of the bed, filling is continued from the top of the bed. - Lake Whitney Water Filtration Plant, Filtration Plant, South side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  3. Microprocessor-Based Valved Controller

    NASA Technical Reports Server (NTRS)

    Norman, Arnold M., Jr.

    1987-01-01

    New controller simpler, more precise, and lighter than predecessors. Mass-flow controller compensates for changing supply pressure and temperature such as occurs when gas-supply tank becomes depleted. By periodically updating calculation of mass-flow rate, controller determines correct new position for valve and keeps mass-flow rate nearly constant.

  4. Energy conservation with automatic flow control valves

    SciTech Connect

    Phillips, D.

    1984-12-01

    Automatic flow control valves are offered in a wide range of sizes starting at 1/2 in. with flow rates of 0.5 gpm and up. They are also provided with materials and end connections to meet virtually any fan-coil system requirement. Among these are copper sweat type valves; ductile iron threaded valves; male/female threaded brass valves; and combination flow control/ball valves with union ends.

  5. Novel Active Combustion Control Valve

    NASA Technical Reports Server (NTRS)

    Caspermeyer, Matt

    2014-01-01

    This project presents an innovative solution for active combustion control. Relative to the state of the art, this concept provides frequency modulation (greater than 1,000 Hz) in combination with high-amplitude modulation (in excess of 30 percent flow) and can be adapted to a large range of fuel injector sizes. Existing valves often have low flow modulation strength. To achieve higher flow modulation requires excessively large valves or too much electrical power to be practical. This active combustion control valve (ACCV) has high-frequency and -amplitude modulation, consumes low electrical power, is closely coupled with the fuel injector for modulation strength, and is practical in size and weight. By mitigating combustion instabilities at higher frequencies than have been previously achieved (approximately 1,000 Hz), this new technology enables gas turbines to run at operating points that produce lower emissions and higher performance.

  6. 137. VALVES ON SOUTH WALL OF LIQUID NITROGEN CONTROL ROOM ...

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

    137. VALVES ON SOUTH WALL OF LIQUID NITROGEN CONTROL ROOM (115), LSB (BLDG. 770) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  7. Noise generated by a flight weight, air flow control valve in a vertical takeoff and landing aircraft thrust vectoring system

    NASA Technical Reports Server (NTRS)

    Huff, Ronald G.

    1989-01-01

    Tests were conducted in the NASA Lewis Research Center's Powered Lift Facility to experimentally evaluate the noise generated by a flight weight, 12 in. butterfly valve installed in a proposed vertical takeoff and landing thrust vectoring system. Fluctuating pressure measurements were made in the circular duct upstream and downstream of the valve. This data report presents the results of these tests. The maximum overall sound pressure level is generated in the duct downstream of the valve and reached a value of 180 dB at a valve pressure ratio of 2.8. At the higher valve pressure ratios the spectra downstream of the valve is broad banded with its maximum at 1000 Hz.

  8. Air-cooled overhead-valve engine

    SciTech Connect

    Shirai, T.

    1987-06-16

    This patent describes an air-cooled overhead-valve internal combustion engine. The engine is composed of a crankcase with a crankshaft, a cylinder block with a cylinder head and a combustion chamber mounted in the crankcase. At least a pair of intake and exhaust valves installed in intake and exhaust ports are formed in the cylinder head. A valve drive system mounted adjacent to the cylinder block drives the intake and exhaust valves through cam-driven push rods. An intake pipe is connected at one end of the intake port and at its opposite end to an air cleaner and a carburetor. An exhaust duct is connected at one end of the exhaust port. A flywheel is joined to the crankshaft at the other end of the output side end of the crankshaft and a cooling fan mounted on the flywheel. The improvements are where the cooling fan is housed, together with the crankcase and flywheel, in a fan casing having a pair of inlet and outlet openings bored in opposite walls. The inlet opening is located at the flywheel side of the crankshaft, while the outlet opening is located at the opposite side of the crankshaft from the flywheel. The cam-driven push rods are located in the crankcase on that side of the cylinder block far remote from where the intake pipe is connected to the intake port. The cooling fan is mounted in the fan casing in such a manner that the cooling air from the cooling fan is allowed to flow in a direction substantially parallel with the axis of the crankshaft, along the surface of the cylinder block and cylinder head.

  9. Isolation of persistent air leaks and placement of intrabronchial valves

    PubMed Central

    Mahajan, Amit K.; Doeing, Diana C.; Hogarth, Douglas K.

    2013-01-01

    Objectives Alveolar-pleural fistulas causing persistent air leaks are conditions associated with prolonged hospital courses, high morbidity, and possibly increased mortality. Intrabronchial valves serve as a noninvasive therapeutic option for the closure of alveolar-pleural fistulas. Methods The present review describes a brief history of, and indications for, the placement of intrabronchial valves in patients with persistent air leaks. The essential steps necessary for placement are air leak isolation, airway sizing, and valve deployment. Additionally, the indications and methods for intrabronchial valve removal, along with the potential complications from intrabronchial valve placement, are described. Conclusions The increased use of intrabronchial valves in the treatment of persistent air leaks requires bronchoscopists and clinicians to understand the procedural steps and techniques necessary for intrabronchial valve placement. PMID:23312104

  10. Improved fluid control valve extends diaphragm life

    NASA Technical Reports Server (NTRS)

    Mac Glashan, W. F.

    1965-01-01

    Wear resistance of flexible diaphragms in fluid control valves is increased by incorporating a soft rubber washer at the bottom of the piston, a flexible buffer between the diaphragm and the valve seat, and a fluid feedback arrangement. The stress and wear of components at the valve seat are minimized.

  11. Fuel-air control device

    SciTech Connect

    Norman, J.

    1981-12-15

    The invention concerns a device for controlling the vehicles fuel-air mixture by regulating the air in the ventilation passage leading to the engine air intake from the crankcase. In a vehicle provided with a PCV valve, the device is located in the ventilation passage leading from the crankcase to the engine air intake and the device is downstream of the PCV valve. The device admits outside air to the ventilation passage to lean the gas mixture when the engine creates a vacuum less than 8 psi in the ventilation passage.

  12. Flow characteristics of control valve for different strokes

    NASA Astrophysics Data System (ADS)

    Jablonská, Jana; Kozubková, Milada

    2016-03-01

    The article deals with the determination of flow characteristics and loss coefficients of control valve when the water flows in the interval of operating parameters, including the evaluation of vapour and air cavitation regime. The characteristics of the control valve are measured on the experimental equipment and subsequently loss coefficients are determined. Data from experimental measurements are used for creating of mathematical model with vapour and air cavitation and verification results. This validation will enable the application of methods of numerical modelling for valves of atypical dimensions e.g. for use in nuclear power industry. The correct knowledge of the valve characteristics and fundamental coefficients (e.g. flow coefficient, cavitation coefficient and loss coefficient) is necessarily required primarily for designers of pipe networks.

  13. An air-pressure-free elastomeric valve for integrated nucleic acid analysis by capillary electrophoresis

    NASA Astrophysics Data System (ADS)

    Jung, Wooseok; Barrett, Matthew; Brooks, Carla; Rivera, Andrew; Birdsell, Dawn N.; Wagner, David M.; Zenhausern, Frederic

    2015-12-01

    We present a new elastomeric valve for integrated nucleic acid analysis by capillary electrophoresis. The valve functions include metering to capture a designated volume of biological sample into a polymerase chain reaction (PCR) chamber, sealing to preserve the sample during PCR cycling, and transfer of the PCR-products and on-chip formamide post-processing for the analysis of DNA fragments by capillary gel electrophoresis. This new valve differs from prior art polydimethylsiloxane (PDMS) valves in that the valve is not actuated externally by air-pressure or vacuum so that it simplifies a DNA analysis system by eliminating the need for an air-pressure or vacuum source, and off-cartridge solenoid valves, control circuit boards and software. Instead, the new valve is actuated by a thermal cycling peltier assembly integrated within the hardware instrument that tightly comes in contact with a microfluidic cartridge for thermal activation during PCR, so that it spontaneously closes the valve without an additional actuator system. The valve has bumps in the designated locations so that it has a self-alignment that does not require precise alignment of a valve actuator. Moreover, the thickness of the new valve is around 600 μm with an additional bump height of 400 μm so that it is easy to handle and very feasible to fabricate by injection molding compared to other PDMS valves whose thicknesses are around 30-100 μm. The new valve provided over 95% of metering performance in filling the fixed volume of the PCR chamber, preserved over 97% of the sample volume during PCR, and showed very comparable capillary electrophoresis peak heights to the benchtop assay tube controls with very consistent transfer volume of the PCR-product and on-chip formamide. The new valve can perform a core function for integrated nucleic acid analysis by capillary electrophoresis.

  14. Valve for controlling solids flow

    DOEpatents

    Staiger, M. Daniel

    1985-01-01

    A valve for controlling the flow of solids comprises a vessel having an overflow point, an inlet line for discharging solids into the vessel positioned within the vessel such that the inlet line's discharge point is lower than the vessel's overflow point, and apparatus for introducing a fluidizing fluid into the vessel. The fluidizing fluid fluidizes the solids within the vessel so that they overflow at the vessel's overflow point. For the removal of nuclear waste product the vessel may be placed within a sealed container having a bottom connected transport line for transporting the solids to storage or other sites. The rate of solids flow is controlled by the flow rate of the fluidizing fluid and by V-notch weirs of different sizes spaced about the top of the vessel.

  15. Valve for controlling solids flow

    DOEpatents

    Staiger, M.D.

    1982-09-29

    A valve for controlling the flow of solids comprises a vessel having an overflow point, an inlet line for discharging solids into the vessel positioned within the vessel such that the inlet line's discharge point is lower than the vessel's overflow point, and means for introducing a fluidizing fluid into the vessel. The fluidizing fluid fluidizes the solids within the vessel so that they overflow at the vessel's overflow point. For the removal of nuclear waste product the vessel may be placed within a sealed container having a bottom connected transport line for transporting the solids to storage or other sites. The rate of solids flow is controlled by the flow rate of the fluidizing fluid and by V-notch weirs of different sizes spaced about the top of the vessel.

  16. High precision high flow range control valve

    DOEpatents

    McCray, John A.

    1999-01-01

    A fluid control valve is described having a valve housing having first and second valve housing openings for the ingress and egress of fluid through the control valve. Disposed within a void formed by the control valve is a sleeve having at least one sleeve opening to permit the flow of fluid therethrough. A flow restricter travels within the sleeve to progressively block off the sleeve opening and thereby control flow. A fluid passageway is formed between the first valve housing opening and the outer surface of the sleeve. A second fluid passageway is formed between the inside of the sleeve and the second valve housing opening. Neither fluid passageway contains more than one 90.degree. turn. In the preferred embodiment only one of the two fluid passageways contains a 90.degree. turn. In another embodiment, the control valve housing is bifurcated by a control surface having control surface opening disposed therethrough. A flow restricter is in slidable contact with the control surface to restrict flow of fluid through the control surface openings.

  17. High precision high flow range control valve

    DOEpatents

    McCray, J.A.

    1999-07-13

    A fluid control valve is described having a valve housing having first and second valve housing openings for the ingress and egress of fluid through the control valve. Disposed within a void formed by the control valve is a sleeve having at least one sleeve opening to permit the flow of fluid therethrough. A flow restricter travels within the sleeve to progressively block off the sleeve opening and thereby control flow. A fluid passageway is formed between the first valve housing opening and the outer surface of the sleeve. A second fluid passageway is formed between the inside of the sleeve and the second valve housing opening. Neither fluid passageway contains more than one 90 [degree] turn. In the preferred embodiment only one of the two fluid passageways contains a 90[degree] turn. In another embodiment, the control valve housing is bifurcated by a control surface having control surface opening disposed therethrough. A flow restricter is in slidable contact with the control surface to restrict flow of fluid through the control surface openings. 12 figs.

  18. Hydraulic engine valve actuation system including independent feedback control

    DOEpatents

    Marriott, Craig D

    2013-06-04

    A hydraulic valve actuation assembly may include a housing, a piston, a supply control valve, a closing control valve, and an opening control valve. The housing may define a first fluid chamber, a second fluid chamber, and a third fluid chamber. The piston may be axially secured to an engine valve and located within the first, second and third fluid chambers. The supply control valve may control a hydraulic fluid supply to the piston. The closing control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the second fluid chamber to the supply control valve. The opening control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the supply control valve to the second fluid chamber.

  19. D0 Silicon Upgrade: Control Dewar Valve Calculations

    SciTech Connect

    Rucinski, Russ; /Fermilab

    1995-10-20

    This engineering note documents the calculations that were done to support the valve size selection for the magnet flow control valve, EVMF in the solenoid control dewar. The size selected was a control valve with a Cv = 0.32.

  20. 14 CFR 23.995 - Fuel valves and controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Components § 23.995 Fuel valves and controls. (a) There must be a means to allow appropriate flight crew... valve rapidly after it has been closed. (c) Each valve and fuel system control must be supported so that... lines connected to the valve. (d) Each valve and fuel system control must be installed so that...

  1. 14 CFR 23.995 - Fuel valves and controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Components § 23.995 Fuel valves and controls. (a) There must be a means to allow appropriate flight crew... valve rapidly after it has been closed. (c) Each valve and fuel system control must be supported so that... lines connected to the valve. (d) Each valve and fuel system control must be installed so that...

  2. Adaptive muffler based on controlled flow valves.

    PubMed

    Šteblaj, Peter; Čudina, Mirko; Lipar, Primož; Prezelj, Jurij

    2015-06-01

    An adaptive muffler with a flexible internal structure is considered. Flexibility is achieved using controlled flow valves. The proposed adaptive muffler is able to adapt to changes in engine operating conditions. It consists of a Helmholtz resonator, expansion chamber, and quarter wavelength resonator. Different combinations of the control valves' states at different operating conditions define the main working principle. To control the valve's position, an active noise control approach was used. With the proposed muffler, the transmission loss can be increased by more than 10 dB in the selected frequency range. PMID:26093462

  3. Spool Valve for Switching Air Flows Between Two Beds

    NASA Technical Reports Server (NTRS)

    Dean, W. Clark

    2005-01-01

    U.S. Patent 6,142,151 describes a dual-bed ventilation system for a space suit, with emphasis on a multiport spool valve that switches air flows between two chemical beds that adsorb carbon dioxide and water vapor. The valve is used to alternately make the air flow through one bed while exposing the other bed to the outer-space environment to regenerate that bed through vacuum desorption of CO2 and H2O. Oxygen flowing from a supply tank is routed through a pair of periodically switched solenoid valves to drive the spool valve in a reciprocating motion. The spool valve equalizes the pressures of air in the beds and the volumes of air flowing into and out of the beds during the alternations between the adsorption and desorption phases, in such a manner that the volume of air that must be vented to outer space is half of what it would be in the absence of pressure equalization. Oxygen that has been used to actuate the spool valve in its reciprocating motion is released into the ventilation loop to replenish air lost to vacuum during the previous desorption phase of the operating cycle.

  4. Steam turbine control valve for cyclic duty

    SciTech Connect

    Dawawala, S.K.; La Coste, B.L.

    1987-07-14

    This patent describes a turbine control valve comprising: a body having a cavity with an elongated generally round first opening on one side. The first opening has a circumferential sealing surface adjacent. A generally round second opening with a valve seat disposes on a side opposite the first opening, and a third opening for admitting steam to the cavity; a valve plug which mates with the valve seat to close off the second opening; a bonnet having a generally cylindrical portion with an integral flange on one end of the cylindrical portion, the flange has a circumferential seal surface which mates with the circumferential sealing surface adjacent the first opening; the bonnet has a centrally disposed bore extending with two counter bores inwardly from the end without the flange; the first counter bore is long and terminates with a large fillet radius; the second counter bore is sufficiently deep to receive the plug and also terminates with a fillet radius. The cylindrical portion has a first raised land on the outer surface adjacent the flange and a second raised land on the outer surface and spaced from the first land and the first raised land is larger in diameter than the second raised land. A plug guide is slidably disposed in the hardened sleeve and on the valve stem and affixed to the valve plug so that the sliding motion between the valve stem and the plug guide is small; the valve plug has a centrally disposed port extending which cooperates with the valve stem to provide means for reducing the force required to remove the plug from the seat to form a control valve operable for cyclic duty where large temperature changes occur at the plug.

  5. Flow Characteristics Analysis of Widows' Creek Type Control Valve for Steam Turbine Control

    SciTech Connect

    Yoo, Yong H.; Sohn, Myoung S.; Suh, Kune Y.

    2006-07-01

    The steam turbine converts the kinetic energy of steam to mechanical energy of rotor blades in the power conversion system of fossil and nuclear power plants. The electric output from the generator of which the rotor is coupled with that of the steam turbine depends on the rotation velocity of the steam turbine bucket. The rotation velocity is proportional to the mass flow rate of steam entering the steam turbine through valves and nozzles. Thus, it is very important to control the steam mass flow rate for the load following operation of power plants. Among various valves that control the steam turbine, the control valve is most significant. The steam flow rate is determined by the area formed by the stem disk and the seat of the control valve. While the ideal control valve linearly controls the steam mass flow rate with its stem lift, the real control valve has various flow characteristic curves pursuant to the stem lift type. Thus, flow characteristic curves are needed to precisely design the control valves manufactured for the operating conditions of nuclear power plants. OMEGA (Optimized Multidimensional Experiment Geometric Apparatus) was built to experimentally study the flow characteristics of steam flowing inside the control valve. The Widows' Creek type control valve was selected for reference. Air was selected as the working fluid in the OMEGA loop to exclude the condensation effect in this simplified approach. Flow characteristic curves were plotted by calculating the ratio of the measured mass flow rate versus the theoretical mass flow rate of the air. The flow characteristic curves are expected to be utilized to accurately design and operate the control valve for fossil as well as nuclear plants. (authors)

  6. Management of Prolonged Pulmonary Air Leaks With Endobronchial Valve Placement

    PubMed Central

    Doelken, Peter; Pupovac, Stevan; Ata, Ashar; Fabian, Tom

    2016-01-01

    Background: Prolonged pulmonary air leaks (PALs) are associated with increased morbidity and extended hospital stay. We sought to investigate the role of bronchoscopic placement of 1-way valves in treating this condition. Methods: We queried a prospectively maintained database of patients with PAL lasting more than 7 days at a tertiary medical center. Main outcome measures included duration of chest tube placement and hospital stay before and after valve deployment. Results: Sixteen patients were eligible to be enrolled from September 2012 through December 2014. One patient refused to give consent, and in 4 patients, the source of air leak could not be identified with bronchoscopic balloon occlusion. Eleven patients (9 men; mean age, 65 ± 15 years) underwent bronchoscopic valve deployment. Eight patients had postoperative PAL and 3 had a secondary spontaneous pneumothorax. The mean duration of air leak before valve deployment was 16 ± 12 days, and the mean number of implanted valves was 1.9 (median, 2). Mean duration of hospital stay before and after valve deployment was 18 and 9 days, respectively (P = .03). Patients who had more than a 50% decrease in air leak on digital monitoring had the thoracostomy tube removed within 3–6 days. There were no procedural complications related to deployment or removal of the valves. Conclusions: Bronchoscopic placement of 1-way valves is a safe procedure that could help manage patients with prolonged PAL. A prospective randomized trial with cost-efficiency analysis is necessary to better define the role of this bronchoscopic intervention and demonstrate its effect on air leak duration.

  7. Management of Prolonged Pulmonary Air Leaks With Endobronchial Valve Placement

    PubMed Central

    Doelken, Peter; Pupovac, Stevan; Ata, Ashar; Fabian, Tom

    2016-01-01

    Background: Prolonged pulmonary air leaks (PALs) are associated with increased morbidity and extended hospital stay. We sought to investigate the role of bronchoscopic placement of 1-way valves in treating this condition. Methods: We queried a prospectively maintained database of patients with PAL lasting more than 7 days at a tertiary medical center. Main outcome measures included duration of chest tube placement and hospital stay before and after valve deployment. Results: Sixteen patients were eligible to be enrolled from September 2012 through December 2014. One patient refused to give consent, and in 4 patients, the source of air leak could not be identified with bronchoscopic balloon occlusion. Eleven patients (9 men; mean age, 65 ± 15 years) underwent bronchoscopic valve deployment. Eight patients had postoperative PAL and 3 had a secondary spontaneous pneumothorax. The mean duration of air leak before valve deployment was 16 ± 12 days, and the mean number of implanted valves was 1.9 (median, 2). Mean duration of hospital stay before and after valve deployment was 18 and 9 days, respectively (P = .03). Patients who had more than a 50% decrease in air leak on digital monitoring had the thoracostomy tube removed within 3–6 days. There were no procedural complications related to deployment or removal of the valves. Conclusions: Bronchoscopic placement of 1-way valves is a safe procedure that could help manage patients with prolonged PAL. A prospective randomized trial with cost-efficiency analysis is necessary to better define the role of this bronchoscopic intervention and demonstrate its effect on air leak duration. PMID:27647978

  8. 30. Engine controls and valve gear, looking aft on main ...

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

    30. Engine controls and valve gear, looking aft on main (promenade) deck level. Threaded admission valve lift rods (two at immediate left of chronometer) permit adjustment of valve timing in lower and upper admission valves of cylinder (left rod controls lower valve, right rod upper valve). Valve rods are lifted by jaw-like "wipers" during operation. Exhaust valve lift rods and wipers are located to right of chronometer. Crank at extreme right drives valve wiper shaft when engaged to end of eccentric rod, shown under "Crank Indicator" dial. Pair of handles to immediate left of admission valve rods control condenser water valves; handles to right of exhaust valve rods control feedwater flow to boilers from pumps. Gauges indicate boiler pressure (left) and condenser vacuum (right); "Crank Indicator" on wall aids engineer in keeping engine crank off "dead-center" at stop so that engine may be easily restarted. - Ferry TICONDEROGA, Route 7, Shelburne, Chittenden County, VT

  9. Hydraulic servo control spool valve

    DOEpatents

    Miller, Donald M.

    1983-01-01

    A servo operated spool valve having a fixed sleeve and axially movable spool. The sleeve is machined in two halves to form a long, narrow tapered orifice slot across which a transverse wall of the spool is positioned. The axial position of the spool wall along the slot regulates the open orifice area with extreme precision.

  10. Working characteristics of variable intake valve in compressed air engine.

    PubMed

    Yu, Qihui; Shi, Yan; Cai, Maolin

    2014-01-01

    A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine. PMID:25379536

  11. Working Characteristics of Variable Intake Valve in Compressed Air Engine

    PubMed Central

    Yu, Qihui; Shi, Yan; Cai, Maolin

    2014-01-01

    A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine. PMID:25379536

  12. Xurography actuated valving for centrifugal flow control.

    PubMed

    Kinahan, David J; Early, Philip L; Vembadi, Abhishek; MacNamara, Eoghan; Kilcawley, Niamh A; Glennon, Thomas; Diamond, Dermot; Brabazon, Dermot; Ducrée, Jens

    2016-09-21

    We introduce a novel instrument controlled valving scheme for centrifugal platforms which is based upon xurography. In a first approach, which is akin to previously presented event-triggered flow control, the valves are composed of a pneumatic chamber sealed by a dissolvable film (DF) and by a pierceable membrane. Liquid is initially prevented from wetting the DF by the counter pressure of a trapped gas. Via a channel, this pocket is pneumatically connected to a vent, sealed by the pierceable membrane, located on the top surface of the disc. By scouring the top surface of the disc, along a pre-defined track by a robotic knife-cutter, the trapped gas is released and so the liquid can wet and disintegrate the DF. In order to automate assay protocols without the need to integrate DFs, we extend this xurography-based flow control concept by selective venting of chambers subjected to pneumatic over-pressure or vacuum suction. Unlike most instrument controlled flow-control mechanisms, in this approach to valve actuation can occur during disc rotation. To demonstrate the potential of this flow control approach, we designed a disc architecture to automate the liquid handling as the backbone of a biplex liver assay panel. We demonstrate valve actuation during rotation, using the robotic arm, using this disc with visualisation via dyed water. We then demonstrate the biplex liver assay, using calibration reagent, by stopping the disc and manually piercing the membrane to actuate the same valves. PMID:27523628

  13. Electromechanically Actuated Valve for Controlling Flow Rate

    NASA Technical Reports Server (NTRS)

    Patterson, Paul

    2007-01-01

    A proposed valve for controlling the rate of flow of a fluid would include an electric-motor-driven ball-screw mechanism for adjusting the seating element of the valve to any position between fully closed and fully open. The motor would be of a type that can be electronically controlled to rotate to a specified angular position and to rotate at a specified rate, and the ball screw would enable accurate linear positioning of the seating element as a function of angular position of the motor. Hence, the proposed valve would enable fine electronic control of the rate of flow and the rate of change of flow. The uniqueness of this valve lies in a high degree of integration of the actuation mechanism with the flow-control components into a single, relatively compact unit. A notable feature of this integration is that in addition to being a major part of the actuation mechanism, the ball screw would also be a flow-control component: the ball screw would be hollow so as to contain part of the main flow passage, and one end of the ball screw would be the main seating valve element. The relationships among the components of the valve are best understood by reference to the figure, which presents meridional cross sections of the valve in the fully closed and fully open positions. The motor would be supported by a bracket bolted to the valve body. By means of gears or pulleys and a timing belt, motor drive would be transmitted to a sleeve that would rotate on bearings in the valve body. A ball nut inside the sleeve would be made to rotate with the sleeve by use of a key. The ball screw would pass through and engage the ball nut. A key would prevent rotation of the ball screw in the valve body while allowing the ball screw to translate axially when driven by the ball nut. The outer surface of the ball screw would be threaded only in a mid-length region: the end regions of the outer surface of the ball screw would be polished so that they could act as dynamic sealing surfaces

  14. Emission control valve with gas flow shut-off

    SciTech Connect

    Betterton, J.T.; Glover, A.H.; McKee, T.S.; Romanczuk, C.S.

    1990-03-06

    This patent describes, in an internal combustion engine, a crankcase gas flow control device located between the engine crankcase and the engine fuel-air induction. It comprises: a hollow housing, an apertured member supported at its outer edge by the housing. The apertured member forming an inlet and having an annular seating surface about the inlet aperture which faces the interior of the housing; a rod extending through the housing coaxially with the apertured inlet. The inlet forming member has a central boss portion engaging and supporting an end of the rod; a valve element in the housing and encircling the rod, the valve having a closed end normally seated against the seating surface to block gas flow through the inlet aperture; a coil type spring having one end axially fixed to the rod and another end engaging the valve element for yieldably urging the closed end against the seating surface.

  15. Pressure variable orifice for hydraulic control valve

    NASA Technical Reports Server (NTRS)

    Ammerman, R. L.

    1968-01-01

    Hydraulic valve absorbs impact energy generated in docking or joining of two large bodies by controlling energy release to avoid jarring shock. The area of exit porting presented to the hydraulic control fluid is directly proportional to the pressure acting on the fluid.

  16. THE SNS RESONANCE CONTROL COOLING SYSTEM CONTROL VALVE UPGRADE PERFORMANCE

    SciTech Connect

    Williams, Derrick C; Schubert, James Phillip; Tang, Johnny Y

    2008-01-01

    The normal-conducting linac of the Spallation Neutron Source (SNS) uses 10 separate Resonance Control Cooling System (RCCS) water skids to control the resonance of 6 Drift Tube Linac (DTL) and 4 Coupled Cavity Linac (CCL) accelerating structures. The RCCS water skids use 2 control valves; one to regulate the chilled water flow and the other to bypass water to a chilled water heat exchanger. These valves have hydraulic actuators that provide position and feedback to the control system. Frequency oscillations occur using these hydraulic actuators due to their coarse movement and control of the valves. New pneumatic actuator and control positioners have been installed on the DTL3 RCCS water skid to give finer control and regulation of DTL3 cavity temperature. This paper shows a comparison of resonance control performance for the two valve configurations.

  17. Exhaust gas bypass valve control for thermoelectric generator

    DOEpatents

    Reynolds, Michael G; Yang, Jihui; Meisner, Greogry P.; Stabler, Francis R.; De Bock, Hendrik Pieter Jacobus; Anderson, Todd Alan

    2012-09-04

    A method of controlling engine exhaust flow through at least one of an exhaust bypass and a thermoelectric device via a bypass valve is provided. The method includes: determining a mass flow of exhaust exiting an engine; determining a desired exhaust pressure based on the mass flow of exhaust; comparing the desired exhaust pressure to a determined exhaust pressure; and determining a bypass valve control value based on the comparing, wherein the bypass valve control value is used to control the bypass valve.

  18. 46 CFR 108.443 - Controls and valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Controls and valves. 108.443 Section 108.443 Shipping... valves. (a) At least one control for operating a CO2 system must be outside the space or spaces that the... system protects. Control valves must not be located in a protected space unless the CO2 cylinders...

  19. 46 CFR 108.443 - Controls and valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Controls and valves. 108.443 Section 108.443 Shipping... valves. (a) At least one control for operating a CO2 system must be outside the space or spaces that the... system protects. Control valves must not be located in a protected space unless the CO2 cylinders...

  20. Jet-controlled freeze valve for use in a glass melter

    DOEpatents

    Routt, Kenneth R.

    1986-09-02

    A drain valve for use in a furnace for the melting of thermoplastic material. The furnace includes a drain cavity formed in its bottom for withdrawing a flow of thermoplastic material. The drain valve includes a flow member which include a flow tube having an inlet and outlet for the material, and coaxially disposed concentric tubular members defining annuli surrounding the flow tube. The tubular members include heating and cooling means for the flow tube. The flow member is adapted to fit in mating relationship in the drain cavity. A freeze valve member is disposed adjacent the outlet of the flow member. The freeze valve member includes heating means and has a plurality of air jets adapted to direct streams of pressurized air at the outlet to control the flow of thermoplastic material through the flow members. The drain valve can also be used in a furnace of glass melting that includes a drain cavity for withdrawing molten glass from the furnace. The drain valve includes a flow tube member having an inlet and outlet, and having heating and cooling means. The tube member is adapted to fit in mating relationship with the drain cavity. A freeze valve member is disposed at the outlet of the flow tube member. The freeze valve member includes heating means and has a plurality of air jets adapted to direct a stream of pressurized air at the outlet to control the flow of glass through the flow tube member.

  1. Jet-controlled freeze valve for use in a glass melter

    DOEpatents

    Routt, Kenneth R.

    1986-01-01

    A drain valve for use in a furnace for the melting of thermoplastic material. The furnace includes a drain cavity formed in its bottom for withdrawing a flow of thermoplastic material. The drain valve includes a flow member which include a flow tube having an inlet and outlet for the material, and coaxially disposed concentric tubular members defining annuli surrounding the flow tube. The tubular members include heating and cooling means for the flow tube. The flow member is adapted to fit in mating relationship in the drain cavity. A freeze valve member is disposed adjacent the outlet of the flow member. The freeze valve member includes heating means and has a plurality of air jets adapted to direct streams of pressurized air at the outlet to control the flow of thermoplastic material through the flow members. The drain valve can also be used in a furnace of glass melting that includes a drain cavity for withdrawing molten glass from the furnace. The drain valve includes a flow tube member having an inlet and outlet, and having heating and cooling means. The tube member is adapted to fit in mating relationship with the drain cavity. A freeze valve member is disposed at the outlet of the flow tube member. The freeze valve member includes heating means and has a plurality of air jets adapted to direct a stream of pressurized air at the outlet to control the flow of glass through the flow tube member.

  2. Feasibility and testing of lighweight, energy efficient, additive manufactured pneumatic control valve

    SciTech Connect

    Love, Lonnie J.; Mell, Ellen

    2015-02-01

    AeroValve s innovative pneumatic valve technology recycles compressed air through the valve body with each cycle of the valve, and was reported to reduce compressed air requirements by an average of 25% 30%.This technology collaboration project between ORNL and Aerovalve confirms the energy efficiency of valve performance. Measuring air consumption per work completed, the AeroValve was as much as 85% better than the commercial Festo valve.

  3. Technology Reinvestment Program/Advanced ``Zero Emission'' Control Valve (Phase II)

    SciTech Connect

    J. Napoleon

    1998-12-01

    The objectives of this effort are to determine, develop and demonstrate the feasibility of significantly reducing the cost and expanding the applications for a family of Advanced Zero Emissions Control Valves that meets the fugitive emissions requirements of the 1990 Amendments to the Clean Air Act. This program is a direct technology spin-off from the valve technology that is critical to the US Navy's Nuclear Powered Fleet. These zero emissions valves will allow the Hydrocarbon and Chemical Processing Industries, etc., to maintain their competitiveness and still meet environmental and safety requirements. Phase 2 is directed at refining the basic technologies developed during Phase 1 so that they can be more readily selected and utilized by the target market. In addition to various necessary certifications, the project will develop a full featured digital controller with ``smart valve'' growth capability, expanding valve sizes/applications and identifying valve materials to permit applications in severe operational environments.

  4. 14 CFR 23.995 - Fuel valves and controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Fuel valves and controls. 23.995 Section 23... Components § 23.995 Fuel valves and controls. (a) There must be a means to allow appropriate flight crew members to rapidly shut off, in flight, the fuel to each engine individually. (b) No shutoff valve may...

  5. 14 CFR 23.995 - Fuel valves and controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel valves and controls. 23.995 Section 23... Components § 23.995 Fuel valves and controls. (a) There must be a means to allow appropriate flight crew members to rapidly shut off, in flight, the fuel to each engine individually. (b) No shutoff valve may...

  6. 14 CFR 23.995 - Fuel valves and controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Components § 23.995 Fuel valves and controls. (a) There must be a means to allow appropriate flight crew members to rapidly shut off, in flight, the fuel to each engine individually. (b) No shutoff valve may be... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Fuel valves and controls. 23.995 Section...

  7. VALVE

    DOEpatents

    Arkelyan, A.M.; Rickard, C.L.

    1962-04-17

    A gate valve for controlling the flow of fluid in separate concentric ducts or channels by means of a single valve is described. In one position, the valve sealing discs engage opposed sets of concentric ducts leading to the concentric pipes defining the flow channels to block flow therethrough. In another position, the discs are withdrawn from engagement with the opposed ducts and at the same time a bridging section is interposed therebetween to define concentric paths coextensive with and connecting the opposed ducts to facilitate flow therebetween. A wedge block arrangement is employed with each sealing disc to enable it to engage the ducts. The wedge block arrangement also facilitates unobstructcd withdrawal of the discs out of the intervening space between the sets of ducts. (AEC)

  8. 17. ROSS POWERHOUSE: BUTTERFLY VALVE CONTROLS FOR UNIT 43. THE ...

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

    17. ROSS POWERHOUSE: BUTTERFLY VALVE CONTROLS FOR UNIT 43. THE BUTTERFLY VALVE LOCK INDICATES THE BUTTERFLY VALVE IS CLOSED AS UNIT 43 WAS SHUT DOWN FOR REPAIRS, 1989. - Skagit Power Development, Ross Powerhouse, On Skagit River, 10.7 miles upstream from Newhalem, Newhalem, Whatcom County, WA

  9. Correlation of Exhaust-Valve Temperatures with Engine Operating Conditions and Valve Design in an Air-Cooled Cylinder

    NASA Technical Reports Server (NTRS)

    Zipkin, M A; Sanders, J C

    1945-01-01

    A semiempirical equation correlating exhaust-valve temperatures with engine operating conditions and exhaust-valve design has been developed. The correlation is based on the theory correlating engine and cooling variables developed in a previous NACA report. In addition to the parameters ordinarily used in the correlating equation, a term is included in the equation that is a measure of the resistance of the complex heat-flow paths between the crown of the exhaust valve and a point on the outside surface of the cylinder head. A means for comparing exhaust valves of different designs with respect to cooling is consequently provided. The necessary empirical constants included in the equation were determined from engine investigations of a large air-cooled cylinder. Tests of several valve designs showed that the calculated and experimentally determined exhaust-valve temperatures were in good agreement.

  10. Combustor air flow control method for fuel cell apparatus

    DOEpatents

    Clingerman, Bruce J.; Mowery, Kenneth D.; Ripley, Eugene V.

    2001-01-01

    A method for controlling the heat output of a combustor in a fuel cell apparatus to a fuel processor where the combustor has dual air inlet streams including atmospheric air and fuel cell cathode effluent containing oxygen depleted air. In all operating modes, an enthalpy balance is provided by regulating the quantity of the air flow stream to the combustor to support fuel cell processor heat requirements. A control provides a quick fast forward change in an air valve orifice cross section in response to a calculated predetermined air flow, the molar constituents of the air stream to the combustor, the pressure drop across the air valve, and a look up table of the orifice cross sectional area and valve steps. A feedback loop fine tunes any error between the measured air flow to the combustor and the predetermined air flow.

  11. Uncertainty Analysis for a Virtual Flow Meter Using an Air-Handling Unit Chilled Water Valve

    SciTech Connect

    Song, Li; Wang, Gang; Brambley, Michael R.

    2013-04-28

    A virtual water flow meter is developed that uses the chilled water control valve on an air-handling unit as a measurement device. The flow rate of water through the valve is calculated using the differential pressure across the valve and its associated coil, the valve command, and an empirically determined valve characteristic curve. Thus, the probability of error in the measurements is significantly greater than for conventionally manufactured flow meters. In this paper, mathematical models are developed and used to conduct uncertainty analysis for the virtual flow meter, and the results from the virtual meter are compared to measurements made with an ultrasonic flow meter. Theoretical uncertainty analysis shows that the total uncertainty in flow rates from the virtual flow meter is 1.46% with 95% confidence; comparison of virtual flow meter results with measurements from an ultrasonic flow meter yielded anuncertainty of 1.46% with 99% confidence. The comparable results from the theoretical uncertainty analysis and empirical comparison with the ultrasonic flow meter corroborate each other, and tend to validate the approach to computationally estimating uncertainty for virtual sensors introduced in this study.

  12. 46 CFR 108.443 - Controls and valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... have a remote control that operates only the stop valve and must have a separate remote control for... not have a stop valve must be operated by a remote control that releases the required amount of CO2 into the space protected by the system. (h) Remote controls to each space must be in an enclosure....

  13. 46 CFR 108.443 - Controls and valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... have a remote control that operates only the stop valve and must have a separate remote control for... not have a stop valve must be operated by a remote control that releases the required amount of CO2 into the space protected by the system. (h) Remote controls to each space must be in an enclosure....

  14. Apparatus for adjustably controlling valve movement and fuel injection

    SciTech Connect

    Miller, C.R.; Shyu, T.P.; Weber, J.R.

    1993-08-24

    Apparatus is described for adjustably controlling valve movement and fuel injection of an engine having at least one fuel injection system, one exhaust valve system, one intake valve system, a microprocessor controller for receiving input signals and delivering engine controlling electrical signals, and a liquid pressure system, comprising: a single piezoelectric motor connectable to the microprocessor controller and the liquid pressure system and being adapted to receive engine controlling electrical signals from the microprocessor and controllably delivering pressurized liquid signals to the liquid pressure system in response to the received signal; and a spool valve having a single spool, the valve having a plurality of inlets and outlets and being connectable to the liquid pressure system for receiving pressurized liquid signals therefrom and controllably moving the single spool of the spool valve and delivering valve and injection controlling signals to the valve systems and injector system and controlling both valve movement and fuel injection responsive to engine controlling electrical signals received by the piezoelectric motor.

  15. Computational Analysis of Cryogenic Flow Through a Control Valve

    NASA Technical Reports Server (NTRS)

    Danes, Russell; Woods, Jody; Sulyma, Peter

    2003-01-01

    The initial efforts to develop the capability to model valves used in rocket engine component testing at Stennis Space Center are documented. An axisymmetric model of a control valve with LN2 as the working fluid was developed. The goal was to predict the effect of change in the plug/sear region of the valve prior to testing. The valve flow coefficient was predicted for a range of plug positions. Verification of the calculations was carried out to quantify the uncertainty in the numerical answer. The modeled results compared well qualitatively to experimental trends. Additionally, insights into the flow processes in the valve were obtained. Benefits from the verification process included the ability to use coarser grids and insight into ways to reduce computational time by using double precision accuracy and non-integer grid ratios. Future valve modeling activities will include shape optimization of the valve/seat region and dynamic grid modeling.

  16. Semitoroidal-diaphragm cavitating valve designed for bipropellant flow control

    NASA Technical Reports Server (NTRS)

    Young, A. L.

    1969-01-01

    Valve controls the flow of bipropellant liquids in rocket engines. Throttling and cavitation of the liquids are controlled by axial deflections of a semitoroidal metal diaphram. The valve is highly resistant to corrosion and leakage, and should be useful in food processing and chemical industries.

  17. 49 CFR 393.49 - Control valves for brakes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Control valves for brakes. 393.49 Section 393.49... NECESSARY FOR SAFE OPERATION Brakes § 393.49 Control valves for brakes. (a) General rule. Except as provided..., which is equipped with power brakes, must have the braking system so arranged that one application...

  18. 49 CFR 393.49 - Control valves for brakes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Control valves for brakes. 393.49 Section 393.49... NECESSARY FOR SAFE OPERATION Brakes § 393.49 Control valves for brakes. (a) General rule. Except as provided..., which is equipped with power brakes, must have the braking system so arranged that one application...

  19. 49 CFR 393.49 - Control valves for brakes.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Control valves for brakes. 393.49 Section 393.49... NECESSARY FOR SAFE OPERATION Brakes § 393.49 Control valves for brakes. (a) General rule. Except as provided..., which is equipped with power brakes, must have the braking system so arranged that one application...

  20. 49 CFR 393.49 - Control valves for brakes.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Control valves for brakes. 393.49 Section 393.49... NECESSARY FOR SAFE OPERATION Brakes § 393.49 Control valves for brakes. (a) General rule. Except as provided..., which is equipped with power brakes, must have the braking system so arranged that one application...

  1. 49 CFR 393.49 - Control valves for brakes.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Control valves for brakes. 393.49 Section 393.49... NECESSARY FOR SAFE OPERATION Brakes § 393.49 Control valves for brakes. (a) General rule. Except as provided..., which is equipped with power brakes, must have the braking system so arranged that one application...

  2. Aerodynamic Shutoff Valve

    NASA Technical Reports Server (NTRS)

    Horstman, Raymond H.

    1992-01-01

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

  3. System and method for controlling engine knock using electro-hydraulic valve actuation

    DOEpatents

    Brennan, Daniel G

    2013-12-10

    A control system for an engine includes a knock control module and a valve control module. The knock control module adjusts a period that one or more of an intake valve and an exhaust valve of a cylinder are open based on engine knock corresponding to the cylinder. The valve control module, based on the adjusted period, controls the one or more of the intake valve and the exhaust valve using one or more hydraulic actuators.

  4. Liquid-fuel valve with precise throttling control

    NASA Technical Reports Server (NTRS)

    Mcdougal, A. R.; Porter, R. N.; Riebling, R. W.

    1971-01-01

    Prototype liquid-fuel valve performs on-off and throttling functions in vacuum without component cold-welding or excessive leakage. Valve design enables simple and rapid disassembly and parts replacement and operates with short working stroke, providing maximum throttling sensitivity commensurate with good control.

  5. Sliding pressure control valve for pneumatic hammer drill

    SciTech Connect

    Polsky, Yarom

    2011-08-30

    A pneumatic device control apparatus and method comprising a ported valve slidably fitted over a feed tube of the pneumatic device, and using a compliant biasing device to constrain motion of the valve to provide asymmetric timing for extended pressurization of a power chamber and reduced pressurization of a return chamber of the pneumatic device. The pneumatic device can be a pneumatic hammer drill.

  6. External stress-corrosion cracking of a 1.22-m-diameter type 316 stainless steel air valve

    NASA Technical Reports Server (NTRS)

    Moore, Thomas J.; Telesman, Jack; Moore, Allan S.; Johnson, Dereck F.; Kuivinen, David E.

    1993-01-01

    An investigation was conducted to determine the cause of the failure of a massive AISI Type 316 stainless steel valve which controlled combustion air to a jet engine test facility. Several through-the-wall cracks were present near welded joints in the valve skirt. The valve had been in outdoor service for 18 years. Samples were taken in the cracked regions for metallographic and chemical analyses. Insulating material and sources of water mist in the vicinity of the failed valve were analyzed for chlorides. A scanning electron microscope was used to determine whether foreign elements were present in a crack. On the basis of the information generated, the failure was characterized as external stress-corrosion cracking. The cracking resulted from a combination of residual tensile stress from welding and the presence of aqueous chlorides. Recommended countermeasures are included.

  7. Secondary air control system in an internal combustion engine

    SciTech Connect

    Takeda, K.

    1981-11-10

    This application discloses a secondary air control system in an internal combustion engine. The system comprises: an exhaust gas purifying device mounted on an exhaust pipe; a secondary air control valve which comprises a diaphragm actuated by vacuum pressure for controlling secondary supply air to said exhaust gas purifying device; a solenoid valve for controlling said vacuum pressure which acts upon said secondary air control valve; a vacuum sensor which detects the vacuum pressure at a small venturi of a carburetor; a thermo-sensor for detecting the intake air temperature; an air flow meter mounted on a secondary air supply pipe; a thermo-sensor for detecting the secondary air temperature mounted on said secondary air supply pipe, and; a computer to which said valuum sensor, said thermo-sensors, and said air flow meter are connected so as to feed input signals thereto, said solenoid valve being connected to the output of said computer so as to control the secondary air quantity in response to said input signals.

  8. AIR POLLUTION CONTROL TECHNOLOGIES

    EPA Science Inventory

    This is a chapter for John Wiley & Son's Mechanical Engineers' Handbook, and covers issues involving air pollution control. Various technologies for controlling sulfur oxides is considered including fuel desulfurization. It also considers control of nitrogen oxides including post...

  9. Wheel slip control of ABS using ER valve pressure modulator

    NASA Astrophysics Data System (ADS)

    Choi, Seung-Bok; Cho, Myung-Soo; Kim, Yong-Il; Choi, Young-Tai; Wereley, Norman M.

    2004-07-01

    This paper presents a wheel slip control via sliding mode controller for a new anti-lock brake system (ABS) of a passenger vehicle using electrorheological (ER) valve pressure modulator. The principal design parameters of the ER valves and hydraulic booster are appropriately determined by considering braking pressure variation during ABS operation. An electrically controllable pressure modulator using the ER valves is then constructed and its governing equations are derived. Subsequently, the pressure control performance of the new pressure modulator is experimentally evaluated. The governing equations of motion for a quarter car wheel model are derived and the sliding mode controller is formulated for wheel slip control. Hardware in the loop simulation (HILS) for braking performance evaluation is undertaken in order to demonstrate the effectiveness of the proposed ABS associated with the ER valve pressure modulator.

  10. Fuel control valve construction, parts therefor and methods

    SciTech Connect

    Kelly, S.T.; Katchka, J.R.

    1990-05-29

    This patent describes a fuel control valve construction. It comprises: a housing means having an inlet means adapted to be interconnected to a main burner means, the housing means having a main valve seat for interconnecting the inlet means with the main outlet means, the housing means having a movable main valve member for opening and closing the main valve seat, the housing means having a movable lever carrying the main valve member and having a manually operable actuator means for controlling the operating positions of the lever, the lever having an intermediate cam follower portion and opposed ends disposed on each side of the cam follower portion with one end of the opposed ends being pivotally mounted to the housing means and with the other end of the opposed ends carrying the main valve member, the housing means having biasing means operatively interconnected to the lever to tend to pivot the lever in one direction that opens the main valve member away from its main valve seat.

  11. Pneumatic jet-control valve for dual circulating fluidized beds

    NASA Astrophysics Data System (ADS)

    Jiang, Haibo; Dong, Pengfei; Zhu, Zhiping; Wang, Kun; Zhang, Yukui; Lu, Qinggang

    2015-11-01

    With the rapid development of circulating fluidized bed (CFB) technology in different fields, the disadvantages of conventional non-mechanical valves are becoming more apparent, and they are not suitable to be used in complex CFB systems. In this paper, a novel non-mechanical valve named the jet-control valve is presented which can avoid the fluidization of solid particles. The feasibility and performance characteristics of the new valve are investigated with a cold-model dual CFB. The results show that compared with the conventional non-mechanical valve, the jet-control valve can transfer solid particles steadily over a larger range, prevent artesian flow, and improve the leakage characteristics. The effects of the operating parameters and structural parameters on the minimum aeration velocity, solid flow rate, and maximum solid flow rate are studied. A two-valve model is proposed to explain the transport capacity of the valve for one jet pipe. A semi-theoretical expression is obtained based on the experimental data with a maximum deviation of 30% providing useful guide for scaling-up the design.

  12. Trends in development of automatically controlled pipeline valves

    SciTech Connect

    Popov, N.P.; Il`in, A.Yu.

    1994-07-01

    One of the directions being taken in the field of modern chemical and petroleum machinery construction is the design of reliable, cost-competitive, electrically and actuated valves for pipelines and automatic control systems (ACS) for such valves. The requirements imposed on reliability and quality in the manufacture of automatically controlled pipeline valves are becoming more and more stringent. In order to determine the factors influencing valve reliability indexes, a study was made of a batch of valves with nominal diameter D = 100 mm and rated pressure p = 1.6 MPa, with metal-to-metal seating. It was found that with a seating force corresponding to the design value, initial leakage was observed after 3270 cycles, and with a 140% increase after 2740 cycles. The probability of trouble-free operation of these valves during the course of the guaranteed life (3300 cycles) decreases from 0.999 under the design conditions to 0.79 when the seating force is increased by 60% above the design value. The main factors contributing to greater seating force in comparison with the nominal (design) value are the rigidity of the valve/drive system (determined by the valve design, the type of seating contact, and the construction of the electric drive), the moment of inertia of the rotating parts in the drive, the accuracy of adjustment of the drive, and the response time of the drive when actuated by the ACS.

  13. System for feedback control of air-fuel ratio in internal combustion engine

    SciTech Connect

    Yoneda, K.; Kunome, Y.

    1984-05-08

    A system for feedback control of the air-fuel ratio in a carburetor for an automotive internal combustion engine. The control system includes an auxiliary air bleed passage in the main air bleed of a fuel passage, an electromagnetic valve to periodically open and close the auxiliary air bleed passage, an exhaust sensor to detect a specific component of the exhaust gas as an indication of actual air-fuel ratio, and a control circuit to control the electromagnetic valve based on the output of the exhaust sensor. A vacuum passage connects the auxiliary air bleed passage at a section upstream of the electromagnetic valve to a venturi of the intake passage. A vacuum-responsive valve in the vacuum passage dilutes air admitted through the auxiliary air bleed passage with the venturi vacuum during higher speed operation of the engine to compensate for a tendency of the air through the auxiliary air bleed passage to be augmented.

  14. 19. WORM AND SPUR GEARS FOR CONTROLLING THE PADDLE VALVE ...

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

    19. WORM AND SPUR GEARS FOR CONTROLLING THE PADDLE VALVE IN ONE OF THE LOCK GATES WHICH SEPARATES UPPER AND LOWER CHAMBERS: 1976 - Pawtucket Canal, Swamp Locks, Pawtucket & Merrimack Canals, Lowell, Middlesex County, MA

  15. 20. WORM AND SPUR GEARS FOR CONTROLLING THE PADDLE VALVE ...

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

    20. WORM AND SPUR GEARS FOR CONTROLLING THE PADDLE VALVE IN ONE OF THE GATES BETWEEN THE UPPER AND LOWER CHAMBERS: 1976 - Pawtucket Canal, Swamp Locks, Pawtucket & Merrimack Canals, Lowell, Middlesex County, MA

  16. 18. WORM AND SPUR GEARS FOR CONTROLLING THE PADDLE VALVE ...

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

    18. WORM AND SPUR GEARS FOR CONTROLLING THE PADDLE VALVE IN ONE OF THE GATES BETWEEN THE UPPER AND LOWER CHAMBERS: 1976 - Pawtucket Canal, Swamp Locks, Pawtucket & Merrimack Canals, Lowell, Middlesex County, MA

  17. 8. DETAIL: GENERATOR FLOOR DIABLO POWERHOUSE SHOWING BUTTERFLY VALVE CONTROL, ...

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

    8. DETAIL: GENERATOR FLOOR DIABLO POWERHOUSE SHOWING BUTTERFLY VALVE CONTROL, MOSAIC TILE FLOOR, AS SEEN FROM VISITORS GALLERY, 1989. - Skagit Power Development, Diablo Powerhouse, On Skagit River, 6.1 miles upstream from Newhalem, Newhalem, Whatcom County, WA

  18. 20. GENERATOR #1 NEEDLE VALVE CONTROL WHEEL, WATERWHEEL GOVERNOR, PENSTOCK ...

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

    20. GENERATOR #1 NEEDLE VALVE CONTROL WHEEL, WATERWHEEL GOVERNOR, PENSTOCK PRESSURE GAUGE, AND GOVERNOR OIL SET. VIEW TO EAST. - Santa Ana River Hydroelectric System, SAR-2 Powerhouse, Redlands, San Bernardino County, CA

  19. Enhanced Component Performance Study: Air-Operated Valves 1998-2014

    SciTech Connect

    Schroeder, John Alton

    2015-11-01

    This report presents a performance evaluation of air-operated valves (AOVs) at U.S. commercial nuclear power plants. The data used in this study are based on the operating experience failure reports from fiscal year 1998 through 2014 for the component reliability as reported in the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The AOV failure modes considered are failure-to-open/close, failure to operate or control, and spurious operation. The component reliability estimates and the reliability data are trended for the most recent 10-year period, while yearly estimates for reliability are provided for the entire active period. One statistically significant trend was observed in the AOV data: The frequency of demands per reactor year for valves recording the fail-to-open or fail-to-close failure modes, for high-demand valves (those with greater than twenty demands per year), was found to be decreasing. The decrease was about three percent over the ten year period trended.

  20. Turbo-generator control with variable valve actuation

    SciTech Connect

    Vuk, Carl T.

    2011-02-22

    An internal combustion engine incorporating a turbo-generator and one or more variably activated exhaust valves. The exhaust valves are adapted to variably release exhaust gases from a combustion cylinder during a combustion cycle to an exhaust system. The turbo-generator is adapted to receive exhaust gases from the exhaust system and rotationally harness energy therefrom to produce electrical power. A controller is adapted to command the exhaust valve to variably open in response to a desired output for the turbo-generator.

  1. Active control of magnetoresistance of organic spin valves using ferroelectricity

    PubMed Central

    Sun, Dali; Fang, Mei; Xu, Xiaoshan; Jiang, Lu; Guo, Hangwen; Wang, Yanmei; Yang, Wenting; Yin, Lifeng; Snijders, Paul C.; Ward, T. Z.; Gai, Zheng; Zhang, X.-G.; Lee, Ho Nyung; Shen, Jian

    2014-01-01

    Organic spintronic devices have been appealing because of the long spin lifetime of the charge carriers in the organic materials and their low cost, flexibility and chemical diversity. In previous studies, the control of resistance of organic spin valves is generally achieved by the alignment of the magnetization directions of the two ferromagnetic electrodes, generating magnetoresistance. Here we employ a new knob to tune the resistance of organic spin valves by adding a thin ferroelectric interfacial layer between the ferromagnetic electrode and the organic spacer: the magnetoresistance of the spin valve depends strongly on the history of the bias voltage, which is correlated with the polarization of the ferroelectric layer; the magnetoresistance even changes sign when the electric polarization of the ferroelectric layer is reversed. These findings enable active control of resistance using both electric and magnetic fields, opening up possibility for multi-state organic spin valves. PMID:25008155

  2. Active control of magnetoresistance of organic spin valves using ferroelectricity.

    PubMed

    Sun, Dali; Fang, Mei; Xu, Xiaoshan; Jiang, Lu; Guo, Hangwen; Wang, Yanmei; Yang, Wenting; Yin, Lifeng; Snijders, Paul C; Ward, T Z; Gai, Zheng; Zhang, X-G; Lee, Ho Nyung; Shen, Jian

    2014-01-01

    Organic spintronic devices have been appealing because of the long spin lifetime of the charge carriers in the organic materials and their low cost, flexibility and chemical diversity. In previous studies, the control of resistance of organic spin valves is generally achieved by the alignment of the magnetization directions of the two ferromagnetic electrodes, generating magnetoresistance. Here we employ a new knob to tune the resistance of organic spin valves by adding a thin ferroelectric interfacial layer between the ferromagnetic electrode and the organic spacer: the magnetoresistance of the spin valve depends strongly on the history of the bias voltage, which is correlated with the polarization of the ferroelectric layer; the magnetoresistance even changes sign when the electric polarization of the ferroelectric layer is reversed. These findings enable active control of resistance using both electric and magnetic fields, opening up possibility for multi-state organic spin valves. PMID:25008155

  3. Active control of magnetoresistance of organic spin valves using ferroelectricity

    NASA Astrophysics Data System (ADS)

    Shen, Jian

    Organic spintronic devices have been appealing because of the long spin lifetime of the charge carriers in the organic materials and their low cost, flexibility and chemical diversity. In previous studies, the control of resistance of organic spin valves is generally achieved by the alignment of the magnetization directions of the two ferromagnetic electrodes, generating magnetoresistance. Here we employ a new knob to tune the resistance of organic spin valves by adding a thin ferroelectric interfacial layer between the ferromagnetic electrode and the organic spacer: the magnetoresistance of the spin valve depends strongly on the history of the bias voltage, which is correlated with the polarization of the ferroelectric layer; the magnetoresistance even changes sign when the electric polarization of the ferroelectric layer is reversed. These findings enable active control of resistance using both electric and magnetic fields, opening up possibility for multi-state organic spin valves.

  4. Injection pump with radially mounted spill control valve

    SciTech Connect

    Djordjevic, I.

    1987-05-26

    This patent describes a rotary fuel injection pump for an internal combustion engine,. The method comprises: a housing, a rotor rotatable in the housing, a charge pump having radially extending plunger bores in the rotor and a plunger pump for each plunger bore having a pumping plunger reciprocable in the bore. The pumping plunger has outward fuel tank strokes and inward fuel delivery strokes for supplying high pressure charges of fuel for fuel injection. A cam ring surrounds the rotor and is engageable with the plunger pumps to reciprocate the plungers as the rotor rotates. A spill control mechanism has spill valve means connected to the charge pump for spill control of the high pressure charge of fuel. The improvement consists of the spill valve means which comprises at least one rotary spill valve having a valve bore in the rotor oriented transversely to the axis of the rotor and connected to the charge pump through pump passage means and a rotary spill valve member rotatably mounted within the valve bore; and the spill control mechanism.

  5. Valving for controlling a fluid-driven reciprocating apparatus

    DOEpatents

    Whitehead, J.C.

    1995-06-27

    A pair of control valve assemblies is described for alternately actuating a pair of fluid-driven free-piston devices by using fluid pressure communication therebetween. Each control valve assembly is switched by a pressure signal depending on the state of its counterpart`s piston. The communication logic is arranged to provide overlap of the forward strokes of the pistons, so that at least one of the pair will always be pressurized. Thus, uninterrupted pumping of liquid is made possible from a pair of free-piston pumps. In addition, the speed and frequency of piston stroking is entirely dependent on the mechanical power load applied. In the case of a pair of pumps, this enables liquid delivery at a substantially constant pressure over the full range of flow rates, from zero to maximum flow. Each of the valve assemblies uses an intake-exhaust valve and a signal valve with the signal valve of one pump being connected to be pressure responsive to the piston of the opposite cylinder or pump. 15 figs.

  6. Engine Cycle Analysis of Air Breathing Microwave Rocket with Reed Valves

    SciTech Connect

    Fukunari, Masafumi; Komatsu, Reiji; Yamaguchi, Toshikazu; Komurasaki, Kimiya; Arakawa, Yoshihiro; Katsurayama, Hiroshi

    2011-11-10

    The Microwave Rocket is a candidate for a low cost launcher system. Pulsed plasma generated by a high power millimeter wave beam drives a blast wave, and a vehicle acquires impulsive thrust by exhausting the blast wave. The thrust generation process of the Microwave Rocket is similar to a pulse detonation engine. In order to enhance the performance of its air refreshment, the air-breathing mechanism using reed valves is under development. Ambient air is taken to the thruster through reed valves. Reed valves are closed while the inside pressure is high enough. After the time when the shock wave exhausts at the open end, an expansion wave is driven and propagates to the thrust-wall. The reed valve is opened by the negative gauge pressure induced by the expansion wave and its reflection wave. In these processes, the pressure oscillation is important parameter. In this paper, the pressure oscillation in the thruster was calculated by CFD combined with the flux through from reed valves, which is estimated analytically. As a result, the air-breathing performance is evaluated using Partial Filling Rate (PFR), the ratio of thruster length to diameter L/D, and ratio of opening area of reed valves to superficial area {alpha}. An engine cycle and predicted thrust was explained.

  7. System for controlling automatic transmission having communication control valve means

    SciTech Connect

    Ogasawara, T.; Arakawa, Y.; Sumiya, K.; Sakaguchi, Y.

    1987-01-06

    A system is described for hydraulically controlling an automatic transmission equipped with a gear mechanism having elements and friction engaging means therefor for attaining a shift ranges by locking and releasing at least one of the elements of the gear mechanism. It is disposed between an input shaft and an output shaft, to and from a case, by bringing the elements into and out of engagement with one of the input shaft, the output shaft, and each other. The system comprises: a first and a second friction engaging means which take part in achieving at least two speed ranges comprising a higher speed range and a lower speed range; the first friction engaging means taking part in achieving a gear train of the higher speed range between the input and output shafts, and the second friction engaging means taking part in achieving a gear train of the lower speed range; a first and a second hydraulic servo means for actuating the first and the second friction engaging means, respectively; a third hydraulic servo means which is disposed to act opposing to the second hydraulic servo means and is communicated with the first hydraulic servo means; a hydraulic pressure source for generating a hydraulic pressure; a regulator valve for regulating the hydraulic pressure from the hydraulic pressure source into a given pressure; and a first signal hydraulic pressure valve for generating a first signal pressure related with the operation conditions of an engine for driving the input shaft, the conditions including at least output of the engine.

  8. Directional control valve with the ability to "dangle"

    NASA Astrophysics Data System (ADS)

    Meller, Michael; Tiwari, Rashi; Garcia, Ephrahim

    2011-04-01

    The majority of double-acting hydraulic cylinders are controlled via a 4/3 spool valve, which allows for the active movement of the cylinder in two directions, as well as holding its current position. These control valves lack the ability to "dangle," or rather, the ability to permit the hydraulic cylinder to freely sway passively in response to external forces. Including the ability to dangle within a control valve is of particular interest for a number of reasons. It allows for much more naturalistic actuation of the hydraulic cylinder, making it further compatible with bio-inspired platforms, such as driving the legs of a prosthetic limb or an exoskeleton for human augmentation. Additionally, dangle offers an opportunity for considerable efficiency gains. This is possible because the momentum of the load, gravity, among other external forces, can be utilized to move the actuator instead of solely relying on an active input. A novel control valve that integrates all of the features of a 4/3 spool valve in addition to dangle is reported herein.

  9. Valve

    DOEpatents

    Cho, Nakwon

    1980-01-01

    A positive acting valve suitable for operation in a corrosive environment is provided. The valve includes a hollow valve body defining an open-ended bore for receiving two, axially aligned, spaced-apart, cylindrical inserts. One insert, designated the seat insert, terminates inside the valve body in an annular face which lies within plane normal to the axis of the two inserts. An elastomeric O-ring seal is disposed in a groove extending about the annular face. The other insert, designated the wedge insert, terminates inside the valve body in at least two surfaces oppositely inclined with respect to each other and with respect to a plane normal to the axis of the two inserts. An elongated reciprocable gate, movable between the two inserts along a path normal to the axis of the two inserts, has a first flat face portion disposed adjacent and parallel to the annular face of the seat insert. The gate has a second face portion opposite to the first face portion provided with at least two oppositely inclined surfaces for mating with respective inclined surfaces of the wedge insert. An opening is provided through the gate which registers with a flow passage through the two inserts when the valve is open. Interaction of the respective inclined surfaces of the gate and wedge insert act to force the first flat face portion of the gate against the O-ring seal in the seat insert at the limits of gate displacement where it reaches its respective fully open and fully closed positions.

  10. 46 CFR 108.443 - Controls and valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Controls and valves. 108.443 Section 108.443 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.443 Controls...

  11. D0 Silicon Upgrade: Cryolab Control Valve Modification Information for D0-EVMF-H

    SciTech Connect

    Rucincki, Russ; /Fermilab

    1995-10-26

    This engineering note documents some information regarding the solenoid magnet flow valve, EVMF. See also EN-437 'Control Dewar valve sizing' also for further information on this valve. This note documents the modification done to the valve to change it to a Cv = 0.32.

  12. System and method for controlling hydraulic pressure in electro-hydraulic valve actuation systems

    DOEpatents

    Brennan, Daniel G; Marriott, Craig D; Cowgill, Joel; Wiles, Matthew A; Patton, Kenneth James

    2014-09-23

    A control system for an engine includes a first lift control module and a second lift control module. The first lift control module increases lift of M valves of the engine to a predetermined valve lift during a period before disabling or re-enabling N valves of the engine. The second lift control module decreases the lift of the M valves to a desired valve lift during a period after enabling or re-enabling the N valves of the engine, wherein N and M are integers greater than or equal to one.

  13. Simulation of dynamics of hydraulic system with proportional control valve

    NASA Astrophysics Data System (ADS)

    Bureček, Adam; Hružík, Lumír; Vašina, Martin

    2016-03-01

    Dynamics of a hydraulic system is influenced by several parameters, in this case mainly by proportional control valve, oil bulk modulus, oil viscosity, mass load etc. This paper will be focused on experimental measurement and mathematical simulation of dynamics of a hydraulic system with proportional control valve, linear hydraulic cylinder and mass load. The measurement is performed on experimental equipment that enables realization of dynamic processes of the hydraulic system. Linear hydraulic cylinder with mass load is equipped with position sensor of piston. The movement control of piston rod is ensured by the proportional control valve. The equipment enables to test an influence of parameter settings of regulator of the proportional control valve on position and pressure system responses. The piston position is recorded by magnetostrictive sensor that is located in drilled piston rod side of the linear hydraulic cylinder. Pressures are measured by piezoresistive sensors on the piston side and the piston rod side of the hydraulic cylinder. The measurement is performed during movement of the piston rod with mass load to the required position. There is realized and verified a mathematical model using Matlab SimHydraulics software for this hydraulic system.

  14. Pressure tracking control of vehicle ABS using piezo valve modulator

    NASA Astrophysics Data System (ADS)

    Jeon, Juncheol; Choi, Seung-Bok

    2011-03-01

    This paper presents a wheel slip control for the ABS(anti-lock brake system) of a passenger vehicle using a controllable piezo valve modulator. The ABS is designed to optimize for braking effectiveness and good steerability. As a first step, the principal design parameters of the piezo valve and pressure modulator are appropriately determined by considering the braking pressure variation during the ABS operation. The proposed piezo valve consists of a flapper, pneumatic circuit and a piezostack actuator. In order to get wide control range of the pressure, the pressure modulator is desired. The modulator consists of a dual-type cylinder filled with different substances (fluid and gas) and a piston rod moving vertical axis to transmit the force. Subsequently, a quarter car wheel slip model is formulated and integrated with the governing equation of the piezo valve modulator. A sliding mode controller to achieve the desired slip rate is then designed and implemented. Braking control performances such as brake pressure and slip rate are evaluated via computer simulations.

  15. Acoustic-Modal Testing of the Ares I Launch Abort System Attitude Control Motor Valve

    NASA Technical Reports Server (NTRS)

    Davis, R. Benjamin; Fischbach, Sean R.

    2010-01-01

    The Attitude Control Motor (ACM) is being developed for use in the Launch Abort System (LAS) of NASA's Ares I launch vehicle. The ACM consists of a small solid rocket motor and eight actuated pintle valves that directionally allocate.thrust_- 1t.has-been- predicted-that significant unsteady. pressure.fluctuations.will.exist. inside the-valves during operation. The dominant frequencies of these oscillations correspond to the lowest several acoustic natural frequencies of the individual valves. An acoustic finite element model of the fluid volume inside the valve has been critical to the prediction of these frequencies and their associated mode shapes. This work describes an effort to experimentally validate the acoustic finite model of the valve with an acoustic modal test. The modal test involved instrumenting a flight-like valve with six microphones and then exciting the enclosed air with a loudspeaker. The loudspeaker was configured to deliver broadband noise at relatively high sound pressure levels. The aquired microphone signals were post-processed and compared to results generated from the acoustic finite element model. Initial comparisons between the test data and the model results revealed that additional model refinement was necessary. Specifically, the model was updated to implement a complex impedance boundary condition at the entrance to the valve supply tube. This boundary condition models the frequency-dependent impedance that an acoustic wave will encounter as it reaches the end of the supply tube. Upon invoking this boundary condition, significantly improved agreement between the test data and the model was realized.

  16. Automatic rotary valve actuator

    SciTech Connect

    Cook, W.E.

    1985-03-28

    This report describes the design, construction, and operation of a microcomputer-controlled valve actuator for operating test valves requiring rotary motion of the valve stem. An AIM 65 microcomputer, using a FORTH language program, controls an air motor and air clutch mounted within an oven to accomplish testing at elevated temperatures. The valve actuator closes the test valve until a preset torque is reached and then opens the valve to its initial starting point. The number of cycles and extremes of rotation are tallied and printed as the test progresses. Provisions are made to accept remote signals to stop the test and to indicate to a remote device when the test has been stopped.

  17. Enhanced Component Performance Study: Air-Operated Valves 1998–2013

    SciTech Connect

    Schroeder, John Alton

    2014-10-01

    This report presents a performance evaluation of air-operated valves (AOVs) at U.S. commercial nuclear power plants. The data used in this study are based on the operating experience failure reports from fiscal year 1998 through 2013 for the component reliability as reported in the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The AOV failure modes considered are failure-to-open/close, failure to operate or control, and spurious operation. The component reliability estimates and the reliability data are trended for the most recent 10-year period, while yearly estimates for reliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the AOV failure data.

  18. Control methods and valve arrangement for start-up and shutdown of pressurized combustion and gasification systems integrated with a gas turbine

    DOEpatents

    Provol, Steve J.; Russell, David B.; Isaksson, Matti J.

    1994-01-01

    A power plant having a system for converting coal to power in a gas turbine comprises a coal fed pressurized circulating bed for converting coal to pressurized gases, a gas turbine having a compressor for pressurizing air for the pressurized circulating bed and expander for receiving and expanding hot combustion gases for powering a generator, a first fast acting valve for controlling the pressurized air, a second fast acting valve means for controlling pressurized gas from the compressor to the expander.

  19. OUTLET STRUCTURE AT CROWLEY LAKE, CONTROLS GATE VALVES THAT FORM ...

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

    OUTLET STRUCTURE AT CROWLEY LAKE, CONTROLS GATE VALVES THAT FORM PENSTOCKS AND HEADRACES FOR GORGE POWER PLANTS. WATER AUTHORITY ATTEMPTS TO HAVE AS MUCH WATER AS POSSIBLE PASS THROUGH THE POWER HOUSES - Los Angeles Aqueduct, Crowley Lake Dam, Los Angeles, Los Angeles County, CA

  20. Controlled cyclic stretch bioreactor for tissue-engineered heart valves.

    PubMed

    Syedain, Zeeshan H; Tranquillo, Robert T

    2009-09-01

    A tissue-engineered heart valve (TEHV) represents the ultimate valve replacement, especially for juvenile patients given its growth potential. To date, most TEHV bioreactors have been developed based on pulsed flow of culture medium through the valve lumen to induce strain in the leaflets. Using a strategy for controlled cyclic stretching of tubular constructs reported previously, we developed a controlled cyclic stretch bioreactor for TEHVs that leads to improved tensile and compositional properties. The TEHV is mounted inside a latex tube, which is then cyclically pressurized with culture medium. The root and leaflets stretch commensurately with the latex, the stretching being dictated by the stiffer latex and thus controllable. Medium is also perfused through the lumen at a slow rate in a flow loop to provide nutrient delivery. Fibrin-based TEHVs prepared with human dermal fibroblasts were subjected to three weeks of cyclic stretching with incrementally increasing strain amplitude. The TEHV possessed the tensile stiffness and stiffness anisotropy of leaflets from sheep pulmonary valves and could withstand cyclic pulmonary pressures with similar distension as for a sheep pulmonary artery. PMID:19473698

  1. An Introduction to Controller Performance Assessment in Process Control Class through Stiction in Control Valves

    ERIC Educational Resources Information Center

    Srinivasan, Ranganathan; Rengaswamy, Raghunathan; Harris, Sandra

    2007-01-01

    In this paper, we discuss a simple liquid level experiment that can be used to teach nonlinear phenomena in process control through stiction in control valves. This experiment can be used to introduce the undergraduate students to the area of Controller Performance Assessment (CPA). The experiment is very easy to set-up and demonstrate. While…

  2. Monovalve with integrated fuel injector and port control valve, and engine using same

    DOEpatents

    Milam, David M.

    2001-11-06

    An engine includes an engine casing that defines a hollow piston cavity separated from an exhaust passage and an intake passage by a valve seat. A gas exchange valve member is positioned adjacent the valve seat and is moveable between an open position and a closed position. The gas exchange valve member also defines an opening that opens into the hollow piston cavity. A needle valve member is positioned in the gas exchange valve member adjacent a nozzle outlet and is moveable between an inject position and a blocked position. A port control valve member, which has a hydraulic surface, is mounted around the gas exchange valve member and moveable between an intake position and an exhaust position. A pilot valve is moveable between a first position at which the port control hydraulic surface is exposed to a source of high pressure fluid, and a second position at which the port control hydraulic surface is exposed to a source of low pressure fluid.

  3. Monovalve with integrated fuel injector and port control valve, and engine using same

    DOEpatents

    Milam, David M.

    2002-01-01

    Each cylinder of an internal combustion engine includes a combined gas exchange valve and fuel injector with a port control valve. The port control valve operates to open either an intake passage or an exhaust passage. The operation of the combined device is controlled by a pair of electrical actuators. The device is hydraulically actuated.

  4. Fuel-air ratio controlled carburetion system

    SciTech Connect

    Abbey, H. G.

    1980-02-12

    An automatic control system is disclosed supplying a fuel-air mixture to an internal combustion engine including a variable-venturi carburetor. Air is fed into the input of the venturi, the air passing through the throat thereof whose effective area is adjusted by a mechanism operated by a servo motor. Fuel is fed into the input of the venturi from a fuel reservoir through a main path having a fixed orifice and an auxiliary path formed by a metering valve operated by an auxiliary fuel-control motor. The differential air pressure developed between the inlet of the venturi and the throat thereof is sensed to produce an airvelocity command signal that is applied to a controller adapted to compare the command signal with the servo motor set point to produce an output for governing the servo motor to cause it to seek a null point, thereby defining a closed process control loop. The intake manifold vacuum, which varies in degree as a function of load and speed conditions is sensed to govern the auxiliary fuel-control motor accordingly, is at the same time converted into an auxiliary signal which is applied to the controller in the closed loop to modulate the command signal in a manner establishing an optimum air-fuel ratio under the varying conditions of load and speed.

  5. Metabolite Valves: Dynamic Control of Metabolic Flux for Pathway Engineering

    NASA Astrophysics Data System (ADS)

    Prather, Kristala

    2015-03-01

    Microbial strains have been successfully engineered to produce a wide variety of chemical compounds, several of which have been commercialized. As new products are targeted for biological synthesis, yield is frequently considered a primary driver towards determining feasibility. Theoretical yields can be calculated, establishing an upper limit on the potential conversion of starting substrates to target compounds. Such yields typically ignore loss of substrate to byproducts, with the assumption that competing reactions can be eliminated, usually by deleting the genes encoding the corresponding enzymes. However, when an enzyme encodes an essential gene, especially one involved in primary metabolism, deletion is not a viable option. Reducing gene expression in a static fashion is possible, but this solution ignores the metabolic demand needed for synthesis of the enzymes required for the desired pathway. We have developed Metabolite valves to address this challenge. The valves are designed to allow high flux through the essential enzyme during an initial period where growth is favored. Following an external perturbation, enzyme activity is then reduced, enabling a higher precursor pool to be diverted towards the pathway of interest. We have designed valves with control at both the transcriptional and post-translational levels. In both cases, key enzymes in glucose metabolism are regulated, and two different compounds are targeted for heterologous production. We have measured increased concentrations of intracellular metabolites once the valve is closed, and have demonstrated that these increased pools lead to increased product yields. These metabolite valves should prove broadly useful for dynamic control of metabolic flux, resulting in improvements in product yields.

  6. Rescue therapy using an endobronchial valve and digital air leak monitoring in Invasive Pulmonary Aspergillosis

    PubMed Central

    Tsim, Selina; Paton, Lia; Nicholson, Fiona; Blyth, Kevin G.

    2014-01-01

    In this case report, we describe the utilisation of two recently developed technologies for the successful management of a persistent air leak (PAL) in a critically ill patient in whom cardiothoracic surgical intervention was not possible. We report the case of a young leukaemic woman with a PAL complicating Invasive Pulmonary Aspergillosis (IPA), who was effectively managed using an Endobronchial Valve, supplemented by objective, digital air leak data provided by a Thopaz® device (Medela, Switzerland). PMID:26029572

  7. Design and Implementation of Automatic Air Flow Rate Control System

    NASA Astrophysics Data System (ADS)

    Akbar, A.; Saputra, C.; Munir, M. M.; Khairurrijal

    2016-08-01

    Venturimeter is an apparatus that can be used to measure the air flow rate. In this experiment we designed a venturimeter which equipped with a valve that is used to control the air flow rate. The difference of pressure between the cross sections was measured with the differential pressure sensor GA 100-015WD which can calculate the difference of pressures from 0 to 3737.33 Pa. A 42M048C Z36 stepper motor was used to control the valve. The precision of this motor rotation is about 0.15 °. A Graphical User Interface (GUI) was developed to monitor and set the value of flow rate then an 8-bit microcontroller was used to process the control system In this experiment- the venturimeter has been examined to get the optimal parameter of controller. The results show that the controller can set the stable output air flow rate.

  8. 28. Pump Room interiorMain valve control panel with status indicators ...

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

    28. Pump Room interior-Main valve control panel with status indicators for main flooding/dewatering valves and gates. - Hunters Point Naval Shipyard, Drydock No. 4, East terminus of Palou Avenue, San Francisco, San Francisco County, CA

  9. Engine including hydraulically actuated valvetrain and method of valve overlap control

    DOEpatents

    Cowgill, Joel

    2012-05-08

    An exhaust valve control method may include displacing an exhaust valve in communication with the combustion chamber of an engine to an open position using a hydraulic exhaust valve actuation system and returning the exhaust valve to a closed position using the hydraulic exhaust valve actuation assembly. During closing, the exhaust valve may be displaced for a first duration from the open position to an intermediate closing position at a first velocity by operating the hydraulic exhaust valve actuation assembly in a first mode. The exhaust valve may be displaced for a second duration greater than the first duration from the intermediate closing position to a fully closed position at a second velocity at least eighty percent less than the first velocity by operating the hydraulic exhaust valve actuation assembly in a second mode.

  10. Shuttle Gaseous Hydrogen Venting Risk from Flow Control Valve Failure

    NASA Technical Reports Server (NTRS)

    Drummond, J. Philip; Baurle, Robert A.; Gafney, Richard L.; Norris, Andrew T.; Pellett, Gerald L.; Rock, Kenneth E.

    2009-01-01

    This paper describes a series of studies to assess the potential risk associated with the failure of one of three gaseous hydrogen flow control valves in the orbiter's main propulsion system during the launch of Shuttle Endeavour (STS-126) in November 2008. The studies focused on critical issues associated with the possibility of combustion resulting from release of gaseous hydrogen from the external tank into the atmosphere during assent. The Shuttle Program currently assumes hydrogen venting from the external tank will result in a critical failure. The current effort was conducted to increase understanding of the risk associated with venting hydrogen given the flow control valve failure scenarios being considered in the Integrated In-Flight Anomaly Investigation being conducted by NASA.

  11. Air fuel ratio control apparatus and method for an internal combustion engine with a turbocharger

    SciTech Connect

    Sawamoto, K.; Ikeura, K.; Morita, T.; Yamaguchi, H.

    1984-05-29

    Normally, an air-fuel ratio is controlled in accordance with the engine speed and the intake air quantity of an internal combustion engine with a turbocharger. When the output pressure of the turbocharger increases excessively, an intake relief valve opens to decrease the intake air quantity. In this case, the fuel injection quantity is controlled solely in accordance with the engine speed.

  12. Reduced-impact sliding pressure control valve for pneumatic hammer drill

    DOEpatents

    Polsky, Yarom; Grubelich, Mark C.; Vaughn, Mark R.

    2012-05-15

    A method and means of minimizing the effect of elastic valve recoil in impact applications, such as percussive drilling, where sliding spool valves used inside the percussive device are subject to poor positioning control due to elastic recoil effects experienced when the valve impacts a stroke limiting surface. The improved valve design reduces the reflected velocity of the valve by using either an energy damping material, or a valve assembly with internal damping built-in, to dissipate the compression stress wave produced during impact.

  13. Bronchoscopic treatment of complex persistent air leaks with endobronchial one-way valves.

    PubMed

    Fiorelli, Alfonso; Costanzo, Saveria; Carelli, Emanuele; Di Costanzo, Emilio; Santini, Mario

    2016-04-01

    We reported a case series including 5 patients with persistent air-leaks refractory to standard treatment. All patients were unfit for surgery for the presence of co-morbidities and/or severe respiratory failure due to underlying lung diseases. They were successfully treated with bronchoscopic placement of endobronchial one-way valves. Air-leaks stopped in the first 24 h after the procedure in three patients and 3 and 5 days later, respectively, in the remaining two. No complications were observed and follow-up was uneventful in all patients but one died 25 days after the procedure for systemic sepsis due to peritonis. Patients with important, refractory air leaks having clinical repercussions and unfit for surgery should be early reviewed for bronchoscopic valves treatment.

  14. A study of air-operated valves in U.S. nuclear power plants

    SciTech Connect

    Rothberg, O.; Khericha, S.; Watkins, J.; Holbrook, M.

    2000-02-01

    A study of air-operated valves in nuclear power plant applications was conducted for the NRC Office of Research (the project was initiated by NRC/AEOD). The results of the study were based on visits to seven nuclear power plant sites, literature studies, and examinations of event records in databases available to the NRC. The purpose is to provide information to the NRC staff concerning capabilities and performance of air-operated valves (AOVs). Descriptions of air systems and AOVs were studied along with the support systems and equipment. Systems and equipment that contain AOVs and SOVs were studied to determine their dependencies. Applications of AOVs and SOVs were listed along with current NRC requirements.

  15. Development of Small-sized Fluid Control Valve with Self-holding Function Using Permanent Magnet

    NASA Astrophysics Data System (ADS)

    Akagi, Tetsuya; Dohta, Shujiro; Ueda, Hirofumi

    Recently, force feedback devices in virtual reality and power assisted nursing care systems have received much attention and active research. In such a control system, an actuator and a driving device such as a control valve are mounted on the human body. In this condition, the size and weight of the control valve become serious problems. At the same time, the valve should be operated with lower energy consumption because of using a limited electrical power. The typical electro magnetic solenoid valve drives its spool using a larger solenoid to open the valve. The complex construction of the valve for sealing makes its miniaturization and the fabrication of a low cost valve more difficult. In addition, the solenoid in the valve consumes more electrical power while the valve is kept opening. The purpose of our study is to develop a small-sized, lightweight, lower energy consumption and flexible control valve that can be safe enough to mount on the human body at a lower cost. In our pervious study, we proposed and tested the control valve that can open using a vibration motor. In this study, we propose and test a new type of fluid control valve with a self-holding function. The new valve uses a permanent magnet ball. It has a cylindrical magnet and two solenoids. The self-holding function of the valve is done as follows. When one side of the solenoid is stimulated by the current momentarily, the solenoid gives a repulsive force to the cylindrical magnet. The magnet moves toward the opposite side of the solenoid and is attracted to the iron core. Then, the magnet ball moves toward the cylindrical magnet and opens the orifice. The valve can keep open without electrical energy. As a result, the valve with the extremely lower energy consumption can be developed.

  16. Diaphragm valve for corrosive and high temperature fluid flow control has unique features

    NASA Technical Reports Server (NTRS)

    Ebihara, B. T.; Vary, A.

    1966-01-01

    Monometallic diaphragm valve is used for corrosive and high temperature fluid flow control. The body, diaphragm, and plug of the valve are welded together to form an integral leakproof unit for containing the fluid as it passes through the valve from inlet to outlet.

  17. Fast valve

    DOEpatents

    Van Dyke, William J.

    1992-01-01

    A fast valve is disclosed that can close on the order of 7 milliseconds. It is closed by the force of a compressed air spring with the moving parts of the valve designed to be of very light weight and the valve gate being of wedge shaped with O-ring sealed faces to provide sealing contact without metal to metal contact. The combination of the O-ring seal and an air cushion create a soft final movement of the valve closure to prevent the fast air acting valve from having a harsh closing.

  18. Fast valve

    DOEpatents

    Van Dyke, W.J.

    1992-04-07

    A fast valve is disclosed that can close on the order of 7 milliseconds. It is closed by the force of a compressed air spring with the moving parts of the valve designed to be of very light weight and the valve gate being of wedge shaped with O-ring sealed faces to provide sealing contact without metal to metal contact. The combination of the O-ring seal and an air cushion create a soft final movement of the valve closure to prevent the fast air acting valve from having a harsh closing. 4 figs.

  19. Use of thermocapillary migration in a controllable heat valve

    NASA Technical Reports Server (NTRS)

    Schmid, L. A.

    1982-01-01

    In accordance with the Marangoni effect, immiscible droplets in a host fluid in which a temperature gradient exists move in the direction of increasing temperature. It is proposed that this thermocapillary migration could be used to construct a 'liquid wick' that would return the condensed vapor at the condenser end of a heat pipe back to the evaporator, thus completing the fluid circuit. The droplets would be formed by capillary pressure forcing the condensate through a perforated diaphragm whose temperature would control the droplet flux, and hence the heat flux between the two ends of the heat pipe, thus making it a controllable heat valve.

  20. Electronic control system for air fuel ratio compensation in highlands

    SciTech Connect

    Kimura, J.; Noji, A.

    1981-12-29

    An electronic control system which electronically controls the air fuel ratio of a mixture being supplied to a gasoline engine in highlands is described. An orifice device is provided in a passage through which secondary air is supplied to the venturi section of the engine carburetor. An electronic control unit carries out programmed control of the orifice opening of the orifice device in response to the atmospheric pressure and the engine temperature to create a reference pressure. A further electronic control unit drives a second air control valve provided in the secondary air supply passage along a predetermined operating characteristic pattern in response to the difference between the reference pressure and an actual pressure present in the venturi section of the carburetor. A mixture having an optimum air fuel ratio corresponding to the atmospheric pressure can thus be supplied to the engine from the carburetor.

  1. Controlling Indoor Air Pollution.

    ERIC Educational Resources Information Center

    Nero, Anthony V, Jr.

    1988-01-01

    Discusses the health risks posed by indoor air pollutants, such as airborne combustion products, toxic chemicals, and radioactivity. Questions as to how indoor air might be regulated. Calls for new approaches to environmental protection. (TW)

  2. Self-powered automatic secondary air controllers for woodstoves and small furnaces

    DOEpatents

    Siemer, Darryl D.

    1991-01-01

    A controller for automatically regulating the supply of secondary combustion air to woodstoves and small furnaces. The controller includes a movable air valve for controlling the amount of secondary air admitted into the chamber. A self powered means monitors the concentration of combustible gases and vapors and actuates the movable air valve to increase the supply of secondary air in response to increasing concentrations of the combustible gases and vapors. The self-powered means can be two fluid filled sensor bulbs, one of which has a coating of a combustion catalyst. Alternatively, the self powered means can be two metallic stripes laminated together, one of which is coated with a combustion catalyst, and when heated, causes the air valve to actuate.

  3. 43. VALVEHOUSE FOR NEED VALVE OUTLET WORKS ON GALLERY 2, ...

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

    43. VALVEHOUSE FOR NEED VALVE OUTLET WORKS ON GALLERY 2, SHOWING CONTROL PEDESTAL IN FOREGROUND AND NEEDLE VALVE AIR VENTS IN CENTER. VIEW TO WEST. - Owyhee Dam, Across Owyhee River, Nyssa, Malheur County, OR

  4. Enhanced Component Performance Study: Air-Operated Valves 1998–2012

    SciTech Connect

    T. E. Wierman

    2013-10-01

    This report presents an enhanced performance evaluation of air-operated valves (AOVs) at U.S. commercial nuclear power plants. The data used in this study are based on the operating experience failure reports from fiscal year 1998 through 2012 for the component reliability as reported in the Equipment Performance and Information Exchange (EPIX). Results (beta distributions for failure probabilities upon demand and gamma distributions for rates) are used as inputs to the U.S. Nuclear Regulatory Commission standardized plant analysis risk models of U.S. commercial nuclear power plants. The AOV failure modes considered are failure-to-open/close, failure to operate or control, and spurious operation. The component reliability estimates and the reliability data are trended for the most recent 10-year period while yearly estimates for reliability are provided for the entire active period. No statistically significant increasing trends were identified in the AOV results. Statistically significant decreasing trends were identified in two areas: AOV operation demands less than or equal to 20 demands per year and greater than 20 demands.

  5. Air Pollution Control, Part I.

    ERIC Educational Resources Information Center

    Strauss, Werner, Ed.

    Authoritative reviews in seven areas of current importance in air pollution control are supplied in this volume, the first of a two-part set. Titles contained in this book are: "Dispersion of Pollutants Emitted into the Atmosphere,""The Formation and Control of Oxides of Nitrogen in Air Pollution,""The Control of Sulfur Emissions from Combustion…

  6. Use of duplex stainless steel castings in control valves

    SciTech Connect

    Gossett, J.L.

    1996-07-01

    Duplex stainless steels have enjoyed rapidly increasing popularity in recent years. For numerous reasons the availability of these alloys in the cast form has lagged behind the availability of the wrought form. Commercial demand for control valves in these alloys has driven development of needed information to move into production. A systematic approach was used to develop specifications, suppliers and weld procedures. Corrosion, stress corrosion cracking (SCC), sulfide stress cracking (SSC) and hardness results are also presented for several alloys including; CD3MN (UNS J92205), CD4MCu (UNS J93370) and CD7MCuN (cast UNS S32550).

  7. Air/fuel ratio controller

    SciTech Connect

    Schechter, M.M.; Simko, A.O.

    1980-12-23

    An internal combustion engine has a fuel injection pump and an air/fuel ratio controller. The controller has a lever that is connected to the pump lever. An aneroid moves the controller lever as a function of changes in intake manifold vacuum to maintain a constant air/fuel ratio to the mixture charge. A fuel enrichment linkage is provided that modifies the movement of the fuel flow control lever by the aneroid in response to changes in manifold gas temperature levels and exhaust gas recirculation to maintain the constant air/fuel ratio. A manual override is provided to obtain a richer air/fuel ratio for maximum acceleration.

  8. Optimal Control of the Valve Based on Traveling Wave Method in the Water Hammer Process

    NASA Astrophysics Data System (ADS)

    Cao, H. Z.; Wang, F.; Feng, J. L.; Tan, H. P.

    2011-09-01

    Valve regulation is an effective method for process control during the water hammer. The principle of d'Alembert traveling wave theory was used in this paper to construct the exact analytical solution of the water hammer, and the optimal speed law of the valve that can reduce the water hammer pressure in the maximum extent was obtained. Combining this law with the valve characteristic curve, the principle corresponding to the valve opening changing with time was obtained, which can be used to guide the process of valve closing and to reduce the water hammer pressure in the maximum extent.

  9. A liquid overfeeding military air conditioner with a quench valve

    SciTech Connect

    Mei, V.C.; Chen, F.C.; Bolton, C.W.

    1997-12-31

    A 3.3-ton rated military air-conditioning unit has been studied experimentally for baseline and liquid overfeeding (LOF) operation. The tests before any modification, using the nameplate-specified refrigerant charge, showed the measured cooling capacity to be less than 1% off the rated capacity at 95 F (35 C) ambient temperature. The test results, after modification, indicate that LOF operation outperforms the baseline case over a wide ambient temperature range in terms of cooling capacity, power consumption, and system coefficient of performance (COP). At a 95 F (35 C) test point, LOF operation has a cooling capacity of 51,100 Btu per hour, which is an 18% improvement over the baseline operation capacity of 42,500 Btu per hour. The COP for LOF at 95 F (35 C) is 2.62, which is 29% better than the baseline COP of 2.03. However, an optimal refrigerant charge is essential for LOF to work properly.

  10. Control Performance of Vehicle Abs Featuring ER Valve Pressure Modulator

    NASA Astrophysics Data System (ADS)

    Cho, M. S.; Choi, S. B.; Wereley, N. M.

    In this work, an electrically controllable anti-lock brake system (ABS) for passenger vehicle is developed by utilizing electrorheological (ER) fluid. A pressure modulator which consists of a cylindrical ER valve and the hydraulic booster is constructed in order to achieve sufficient brake pressure variation during ABS operation. The principal design parameters of the modulator are determined by considering ER properties as well as required braking pressure. After investigating pressure controllability of the modulator, a vehicle model which is integrated with the proposed pressure modulator is formulated to design yaw rate controller. A sliding mode controller is designed to obtain desired yaw rate, and the friction forces between roads and wheels are estimated via the estimator. Braking performances of the proposed ABS under various roads are evaluated through the hardware-in-the-loop-simulation (HILS) and the steering stability during braking operation is demonstrated by undertaking split-μ test.

  11. Fluid-driven reciprocating apparatus and valving for controlling same

    DOEpatents

    Whitehead, John C.; Toews, Hans G.

    1993-01-01

    A control valve assembly for alternately actuating a pair of fluid-driven free-piston devices by using fluid pressure communication therebetween. Each control valve is switched by a pressure signal depending on the state of its counterpart's piston. The communication logic is arranged to provide overlap of the forward strokes of the pistons, so that at least one of the pair will always be pressurized. Thus, uninterrupted pumping of liquid is made possible from a pair of free-piston pumps. In addition, the speed and frequency of piston stroking is entirely dependent on the mechanical power load applied. In the case of a pair of pumps, this enables liquid delivery at a substantially constant pressure over the full range of flow rates, from zero to maximum flow. One embodiment of the invention utilized two pairs of fluid-driven free-piston devices whereby a bipropellant liquid propulsion system may be operated, so as to provide continuous flow of both fuel and oxidizer liquids when used in rocket applications, for example.

  12. Development of myoelectric control type speaking valve with low flow resistance

    NASA Astrophysics Data System (ADS)

    Ooe, Katsutoshi; Sakurai, Kohei; Mimaki, Shinya

    2015-12-01

    We aimed to develop welfare devices for patients with phonation disorder. One of these devices is the electrical controltype speaking valve system. The conventional speaking valves have one-way valve architecture, they open when the user breathes in, and they close when user breathes out and produce voices. This type is very simple and tough, but some users feel closeness in case of exhalation without phonation. This problem is caused by its mechanism what can not be controlled by user's will. Therefore, we proposed an electrical control-type speaking valve system to resolve this problem. This valve is controlled by neck myoelectric signal of sternohyoid muscle. From our previous report, it was clarified that this valve had better performance about easy-to-breath. Furthermore, we proposed the compact myoelectric control-type speaking valve system. The new-type speaking valve was enough small to attach the human body, and its opening area is larger than that of conventional one. Additionally, we described the improvement of flow channel shape by using of FEM analysis. According to the result of the analysis, it was clarified that the shape-improved speaking valve gets the low flow resistance channel in case of inspiration. In this report, we tried to make the flow resistance lower by the shape of current plates, in case of both inspiration and exhalation. From the result of FEM analysis, our speaking valve could get better flow channel than older one.

  13. Study on flow-induced vibration of cage type control valve

    NASA Astrophysics Data System (ADS)

    Tu, Shan; Wang, Chao; Tang, Yulin; Dong, De

    2013-07-01

    In cage type control valve, sleeve throttling window is used to set flow characteristic curve, which is widely applied in engineering. The internal structure of the cage-type valve is complicated, so the flow field inside the valve is unsteady complex flow. There are a large number of vortexes in the valve chamber, which are the main excitation source that induced control valve vibration. Through-flow structure of the control valve changes in different openings, which leads to the variation of the jet direction when the fluid flows through the throttling window, and in medium and small opening, the situation is more complicated. In this paper, high-frequency pulsating dynamic pressure of the fluid inside the valve has been measured, in order to monitor the internal flow field of the valve. Meanwhile, threedimensional numerical simulation has been carried out to analyze the internal flow field of the valve, and main causes of different vibrations have been found and several ways to weaken the vibration are proposed, which is significant for vibration reduction research of control valve. For the flow-induced vibration in the complex flow channel, the research has great theoretical significance.

  14. Hydraulic High Pressure Valve Controller Using the In-Situ Pressure Difference

    NASA Technical Reports Server (NTRS)

    Bao, Xiaoqi (Inventor); Sherrit, Stewart (Inventor); Badescu, Mircea (Inventor); Bar-Cohen, Yoseph (Inventor); Hall, Jeffery L. (Inventor)

    2016-01-01

    A hydraulic valve controller that uses an existing pressure differential as some or all of the power source for valve operation. In a high pressure environment, such as downhole in an oil or gas well, the pressure differential between the inside of a pipe and the outside of the pipe may be adequately large to drive a linear slide valve. The valve is operated hydraulically by a piston in a bore. When a higher pressure is applied to one end of the bore and a lower pressure to the other end, the piston moves in response to the pressure differential and drives a valve attached to it. If the pressure differential is too small to drive the piston at a sufficiently high speed, a pump is provided to generate a larger pressure differential to be applied. The apparatus is conveniently constructed using multiport valves, which can be rotary valves.

  15. A piezoelectric micro control valve with integrated capacitive sensing for ambulant blood pressure waveform monitoring

    NASA Astrophysics Data System (ADS)

    Groen, Maarten S.; Wu, Kai; Brookhuis, Robert A.; van Houwelingen, Marc J.; Brouwer, Dannis M.; Lötters, Joost C.; Wiegerink, Remco J.

    2014-12-01

    We have designed and characterized a MEMS microvalve with built-in capacitive displacement sensing and fitted it with a miniature piezoelectric actuator to achieve active valve control. The integrated displacement sensor enables high bandwidth proportional control of the gas flow through the valve. This is an essential requirement for non-invasive blood pressure waveform monitoring based on following the arterial pressure with a counter pressure. Using the capacitive sensor, we demonstrate negligible hysteresis in the valve control characteristics. Fabrication of the valve requires only two mask steps for deep reactive ion etching (DRIE) and one release etch.

  16. Gas flow in plant microfluidic networks controlled by capillary valves.

    PubMed

    Capron, M; Tordjeman, Ph; Charru, F; Badel, E; Cochard, H

    2014-03-01

    The xylem vessels of trees constitute a model natural microfluidic system. In this work, we have studied the mechanism of air flow in the Populus xylem. The vessel microstructure was characterized by optical microscopy, transmission electronic microscopy (TEM), and atomic force microscopy (AFM) at different length scales. The xylem vessels have length ≈15 cm and diameter ≈20μm. Flow from one vessel to the next occurs through ∼102 pits, which are grouped together at the ends of the vessels. The pits contain a thin, porous pit membrane with a thickness of 310 nm. We have measured the Young's moduli of the vessel wall and of the pits (both water-saturated and after drying) by specific nanoindentation and nanoflexion experiments with AFM. We found that both the dried and water-saturated pit membranes have Young's modulus around 0.4 MPa, in agreement with values obtained by micromolding of pits deformed by an applied pressure difference. Air injection experiments reveal that air flows through the xylem vessels when the differential pressure across a sample is larger than a critical value ΔPc=1.8 MPa. In order to model the air flow rate for ΔP⩾ΔPc, we assumed the pit membrane to be a porous medium that is strained by the applied pressure difference. Water menisci in the pit pores play the role of capillary valves, which open at ΔP=ΔPc. From the point of view of the plant physiology, this work presents a basic understanding of the physics of bordered pits. PMID:24730949

  17. Gas flow in plant microfluidic networks controlled by capillary valves.

    PubMed

    Capron, M; Tordjeman, Ph; Charru, F; Badel, E; Cochard, H

    2014-03-01

    The xylem vessels of trees constitute a model natural microfluidic system. In this work, we have studied the mechanism of air flow in the Populus xylem. The vessel microstructure was characterized by optical microscopy, transmission electronic microscopy (TEM), and atomic force microscopy (AFM) at different length scales. The xylem vessels have length ≈15 cm and diameter ≈20μm. Flow from one vessel to the next occurs through ∼102 pits, which are grouped together at the ends of the vessels. The pits contain a thin, porous pit membrane with a thickness of 310 nm. We have measured the Young's moduli of the vessel wall and of the pits (both water-saturated and after drying) by specific nanoindentation and nanoflexion experiments with AFM. We found that both the dried and water-saturated pit membranes have Young's modulus around 0.4 MPa, in agreement with values obtained by micromolding of pits deformed by an applied pressure difference. Air injection experiments reveal that air flows through the xylem vessels when the differential pressure across a sample is larger than a critical value ΔPc=1.8 MPa. In order to model the air flow rate for ΔP⩾ΔPc, we assumed the pit membrane to be a porous medium that is strained by the applied pressure difference. Water menisci in the pit pores play the role of capillary valves, which open at ΔP=ΔPc. From the point of view of the plant physiology, this work presents a basic understanding of the physics of bordered pits.

  18. Development and Characterization Testing of an Air Pulsation Valve for a Pulse Detonation Engine Supersonic Parametric Inlet Test Section

    NASA Technical Reports Server (NTRS)

    Tornabene, Robert

    2005-01-01

    In pulse detonation engines, the potential exists for gas pulses from the combustor to travel upstream and adversely affect the inlet performance of the engine. In order to determine the effect of these high frequency pulses on the inlet performance, an air pulsation valve was developed to provide air pulses downstream of a supersonic parametric inlet test section. The purpose of this report is to document the design and characterization tests that were performed on a pulsation valve that was tested at the NASA Glenn Research Center 1x1 Supersonic Wind Tunnel (SWT) test facility. The high air flow pulsation valve design philosophy and analyses performed are discussed and characterization test results are presented. The pulsation valve model was devised based on the concept of using a free spinning ball valve driven from a variable speed electric motor to generate air flow pulses at preset frequencies. In order to deliver the proper flow rate, the flow port was contoured to maximize flow rate and minimize pressure drop. To obtain sharp pressure spikes the valve flow port was designed to be as narrow as possible to minimize port dwell time.

  19. Broadcast control of air traffic

    NASA Technical Reports Server (NTRS)

    Litchford, G. B.

    1972-01-01

    The development of a system of broadcast control for improved flight safety and air traffic control is discussed. The system provides a balance of equality between improved cockpit guidance and control capability and ground control in order to provide the pilot with a greater degree of participation. The manner in which the system is operated and the equipment required for safe operation are examined.

  20. Electromagnetic valve for controlling the flow of molten, magnetic material

    DOEpatents

    Richter, T.

    1998-06-16

    An electromagnetic valve for controlling the flow of molten, magnetic material is provided, which comprises an induction coil for generating a magnetic field in response to an applied alternating electrical current, a housing, and a refractory composite nozzle. The nozzle is comprised of an inner sleeve composed of an erosion resistant refractory material (e.g., a zirconia ceramic) through which molten, magnetic metal flows, a refractory outer shell, and an intermediate compressible refractory material, e.g., unset, high alumina, thermosetting mortar. The compressible refractory material is sandwiched between the inner sleeve and outer shell, and absorbs differential expansion stresses that develop within the nozzle due to extreme thermal gradients. The sandwiched layer of compressible refractory material prevents destructive cracks from developing in the refractory outer shell. 5 figs.

  1. Electromagnetic valve for controlling the flow of molten, magnetic material

    DOEpatents

    Richter, Tomas

    1998-01-01

    An electromagnetic valve for controlling the flow of molten, magnetic material is provided, which comprises an induction coil for generating a magnetic field in response to an applied alternating electrical current, a housing, and a refractory composite nozzle. The nozzle is comprised of an inner sleeve composed of an erosion resistant refractory material (e.g., a zirconia ceramic) through which molten, magnetic metal flows, a refractory outer shell, and an intermediate compressible refractory material, e.g., unset, high alumina, thermosetting mortar. The compressible refractory material is sandwiched between the inner sleeve and outer shell, and absorbs differential expansion stresses that develop within the nozzle due to extreme thermal gradients. The sandwiched layer of compressible refractory material prevents destructive cracks from developing in the refractory outer shell.

  2. Dual-Use Partnership Addresses Performance Problems with "Y" Pattern Control Valves

    NASA Technical Reports Server (NTRS)

    Bailey, John W.

    2004-01-01

    A Dual-Use Cooperative Agreement between the Propulsion Test Directorate (PTD) at Stennis Space Center (SSC) and Oceaneering Reflange, Inc. of Houston, TX has produced an improved 'Y' pattern split-body control valve for use in the propulsion test facilities at Stennis Space Center. The split-body, or clamped bonnet technology, provides for a 'cleaner' valve design featuring enhanced performance and increased flow capacity with extended life expectancy. Other points addressed by the partnership include size, weight and costs. Overall size and weight of each valve will be reduced by 50% compared to valves currently in use at SSC. An initial procurement of two 10 inch valves will result in an overall cost reduction of 15% or approximately $50,000 per valve.

  3. Tape underlayment rotary-node (TURN) valves for simple on-chip microfluidic flow control

    PubMed Central

    Markov, Dmitry A.; Manuel, Steven; Shor, Leslie M.; Opalenik, Susan R.; Wikswo, John P.; Samson, Philip C.

    2013-01-01

    We describe a simple and reliable fabrication method for producing multiple, manually activated microfluidic control valves in polydimethylsiloxane (PDMS) devices. These screwdriver-actuated valves reside directly on the microfluidic chip and can provide both simple on/off operation as well as graded control of fluid flow. The fabrication procedure can be easily implemented in any soft lithography lab and requires only two specialized tools – a hot-glue gun and a machined brass mold. To facilitate use in multi-valve fluidic systems, the mold is designed to produce a linear tape that contains a series of plastic rotary nodes with small stainless steel machine screws that form individual valves which can be easily separated for applications when only single valves are required. The tape and its valves are placed on the surface of a partially cured thin PDMS microchannel device while the PDMS is still on the soft-lithographic master, with the master providing alignment marks for the tape. The tape is permanently affixed to the microchannel device by pouring an over-layer of PDMS, to form a full-thickness device with the tape as an enclosed underlayment. The advantages of these Tape Underlayment Rotary-Node (TURN) valves include parallel fabrication of multiple valves, low risk of damaging a microfluidic device during valve installation, high torque, elimination of stripped threads, the capabilities of TURN hydraulic actuators, and facile customization of TURN molds. We have utilized these valves to control microfluidic flow, to control the onset of molecular diffusion, and to manipulate channel connectivity. Practical applications of TURN valves include control of loading and chemokine release in chemotaxis assay devices, flow in microfluidic bioreactors, and channel connectivity in microfluidic devices intended to study competition and predator / prey relationships among microbes. PMID:19859812

  4. High-Pressure Valve With Controlled Seating Force

    NASA Technical Reports Server (NTRS)

    Bradley, R. H.

    1987-01-01

    Poppet and seat less likely to be damaged by faulty operation. Improvements in widely-used high-pressure valve increase accuracy of preloading of poppet. Redesigned valve prevents metal shavings and other debris from developing during operation, installation, or removal. New features include secondary seal in cap. Belleville washers create precise value of seating force. If installer attempts to exceed force, torque limiter gives tactile and aural warning and makes further force increases difficult.

  5. A pneumatically controllable flexible and polymeric microfluidic valve fabricated via in situ development

    NASA Astrophysics Data System (ADS)

    Baek, Ju Yeoul; Park, Ji Young; Ju, Jong Il; Lee, Tae Soo; Lee, Sang Hoon

    2005-05-01

    In this paper, we have developed a pneumatically controllable polydimethylsiloxane (PDMS)-based microfluidic valve. This valve regulates 'On/Off' of flow using the thick centered membrane. To integrate the freely moving thick centered membrane, regional bonding of the PDMS layer is required. Here, we integrated such a membrane employing a water soluble mask as a regional bonding method, and the mask was washed out by flowing distilled water. The fabricated valve showed good 'On/Off' operations in accordance with the applied pneumatic pressure source. The flow rate could be regulated by the pressure applied to the inlet (regulated by changes in the height of the water column) and the compression-/vacuum-period ratio (this means the ratio of 'On' and 'Off' periods in each cycle) in the range of a few microliters per minute. For the durability test, ten valves were operated simultaneously one million times, and no failed valves were observed.

  6. Mathematical model of the Space Shuttle Main Engine gaseous oxygen control valve

    NASA Technical Reports Server (NTRS)

    Langer, Susan L.; Tygielski, Philip

    1992-01-01

    A computer program for modeling transient flow behavior of the GOX control valve (GCV) has been developed which makes it possible to model a variety of operating conditions and changes of physical hardware. The SSME GCV controls the flow of GOX that pressurizes the Pogo accumulator. The model simulates the transient flow behavior of the original, tight stacked, and redesigned valve configurations during start and shutdown. The model reads a user-prepared input file that defines the valve configurations and thus provides maximum flexibility.

  7. Microfluidic Automation using elastomeric valves and droplets: reducing reliance on external controllers

    PubMed Central

    Kim, Sung-Jin; Lai, David; Park, Joong Yull; Yokokawa, Ryuji

    2012-01-01

    This paper gives an overview of elastomeric valve- and droplet-based microfluidic systems designed to minimize the need of external pressure to control fluid flow. This concept article introduces the working principle of representative components in these devices along with relevant biochemical applications. This is followed by providing a perspective on the roles of different microfluidic valves and systems through comparison of their similarities and differences with transistors (valves) and systems in microelectronics. Despite some physical limitation of drawing analogies from electronic circuits, automated microfluidic circuit design can gain insights from electronic circuits to minimize external control units, while implementing high complexity and throughput analysis. PMID:22761019

  8. Air control system providing healthful enclosed environment

    SciTech Connect

    Rhodes, J.A.

    1991-08-27

    This patent describes an environmentally controlled building. It comprises an outer wall defining an outer building perimeter and having at least one fenestration therethrough for passage of personnel; a roof supported by and cooperating with the outer wall to define a building exterior and interior; and an environmental control system for controlling the environment within the building interior, the environmental control system including a heating and air conditioning unit, having an air inlet, for controlling the temperature of air drawing into the air control system; a humidity control unit, having an inlet connected to the heating and air conditioning unit, for controlling the humidity of air within the air control system; an air blower for forcing air from the environmental control system into the building interior; and an air filtering system having an inlet connected to the humidity control unit and an outlet connected to the blower.

  9. Variable-pulse switching circuit accurately controls solenoid-valve actuations

    NASA Technical Reports Server (NTRS)

    Gillett, J. D.

    1967-01-01

    Solid state circuit generating adjustable square wave pulses of sufficient power operates a 28 volt dc solenoid valve at precise time intervals. This circuit is used for precise time control of fluid flow in combustion experiments.

  10. Air Pollution Control, Part II.

    ERIC Educational Resources Information Center

    Strauss, Werner, Ed.

    This book contains five major articles in areas of current importance in air pollution control. They are written by authors who are actively participating in the areas on which they report. It is the aim of each article to completely cover theory, experimentation, and practice in the field discussed. The contents are as follows: Emissions,…

  11. Automatic air flow control in air conditioning ducts

    NASA Technical Reports Server (NTRS)

    Obler, H. D.

    1972-01-01

    Device is designed which automatically selects air flow coming from either of two directions and which can be adjusted to desired air volume on either side. Device uses one movable and two fixed scoops which control air flow and air volume.

  12. Air-leakage control manual

    SciTech Connect

    Maloney, J.

    1991-05-01

    This manual is for builders and designers who are interested in building energy-efficient homes. The purpose of the manual is to provide the ``how and why`` of controlling air leakage by means of a system called the ``Simple Caulk and Seal`` (SIMPLE{center_dot}CS) system. This manual provides an overview of the purpose and contents of the manual; It discusses the forces that affect air leakage in homes and the benefits of controlling air leakage. Also discussed are two earlier approaches for controlling air leakage and the problems with these approaches. It describes the SIMPLE-{center_dot}CS system. It outlines the standard components of the building envelope that require sealing and provides guidelines for sealing them. It outlines a step-by-step procedure for analyzing and planning the sealing effort. The procedure includes (1) identifying areas to be sealed, (2) determining the most effective and convenient stage of construction in which to do the sealing, and (3) designating the appropriate crew member or trade to be responsible for the sealing.

  13. Air-Leakage Control Manual.

    SciTech Connect

    Maloney, Jim; Washington State Energy Office; United States. Bonneville Power Administration.

    1991-05-01

    This manual is for builders and designers who are interested in building energy-efficient homes. The purpose of the manual is to provide the how and why'' of controlling air leakage by means of a system called the Simple Caulk and Seal'' (SIMPLE{center dot}CS) system. This manual provides an overview of the purpose and contents of the manual; It discusses the forces that affect air leakage in homes and the benefits of controlling air leakage. Also discussed are two earlier approaches for controlling air leakage and the problems with these approaches. It describes the SIMPLE-{center dot}CS system. It outlines the standard components of the building envelope that require sealing and provides guidelines for sealing them. It outlines a step-by-step procedure for analyzing and planning the sealing effort. The procedure includes (1) identifying areas to be sealed, (2) determining the most effective and convenient stage of construction in which to do the sealing, and (3) designating the appropriate crew member or trade to be responsible for the sealing.

  14. Rankine cycle condenser pressure control using an energy conversion device bypass valve

    DOEpatents

    Ernst, Timothy C; Nelson, Christopher R; Zigan, James A

    2014-04-01

    The disclosure provides a waste heat recovery system and method in which pressure in a Rankine cycle (RC) system of the WHR system is regulated by diverting working fluid from entering an inlet of an energy conversion device of the RC system. In the system, an inlet of a controllable bypass valve is fluidly coupled to a working fluid path upstream of an energy conversion device of the RC system, and an outlet of the bypass valve is fluidly coupled to the working fluid path upstream of the condenser of the RC system such that working fluid passing through the bypass valve bypasses the energy conversion device and increases the pressure in a condenser. A controller determines the temperature and pressure of the working fluid and controls the bypass valve to regulate pressure in the condenser.

  15. Improve relief valve reliability

    SciTech Connect

    Nelson, W.E.

    1993-01-01

    This paper reports on careful evaluation of safety relief valves and their service conditions which can improve reliability and permit more time between testing. Some factors that aid in getting long-run results are: Use of valves suitable for service, Attention to design of the relieving system (including use of block valves) and Close attention to repair procedures. Use these procedures for each installation, applying good engineering practices. The Clean Air Act of 1990 and other legislation limiting allowable fugitive emissions in a hydrocarbon processing plant will greatly impact safety relief valve installations. Normal leakage rate from a relief valve will require that it be connected to a closed vent system connected to a recovery or control device. Tying the outlet of an existing valve into a header system can cause accelerated corrosion and operating difficulties. Reliability of many existing safety relief valves may be compromised when they are connected to an outlet header without following good engineering practices. The law has been enacted but all the rules have not been promulgated.

  16. Pulse-modulated control of switching valves for an electro-hydraulic servo actuator

    NASA Astrophysics Data System (ADS)

    Tersteegen, Johannes

    1992-02-01

    The consequent step in using digital technology in servohydraulics leads to the use of fast switching electrohydraulic control valves. By changing the pulse duty ratio between opening and closing (pulse width modulation) a quasi-continuous control of the fluid flow can be achieved. The essential design criteria of a valve controlled actuator including the pulse modulated closed loop position control are described. Those computer programs which are dealt with in detail include the digital control circuit with its pulse modulated control as well as fault detection and fault elimination.

  17. Shuttle Primary Reaction Control Subsystem Thruster Fuel Valve Pilot Seal Extrusion: A Failure Correlation

    NASA Technical Reports Server (NTRS)

    Waller, Jess; Saulsberry, Regor L.

    2003-01-01

    Pilot operated valves (POVs) are used to control the flow of hypergolic propellants monomethylhydrazine (fuel) and nitrogen tetroxide (oxidizer) to the Shuttle orbiter Primary Reaction Control Subsystem (PRCS) thrusters. The POV incorporates a two-stage design: a solenoid-actuated pilot stage, which in turn controls a pressure-actuated main stage. Isolation of propellant supply from the thruster chamber is accomplished in part by a captive polytetrafluoroethylene (PTFE) pilot seal retained inside a Custom 455.1 stainless steel cavity. Extrusion of the pilot seal restricts the flow of fuel around the pilot poppet, thus impeding or preventing the main valve stage from opening. It can also prevent the main stage from staying open with adequate force margin, particularly if there is gas in the main stage actuation cavity. During thruster operation on-orbit, fuel valve pilot seal extrusion is commonly indicated by low or erratic chamber pressure or failure of the thruster to fire upon command (Fail-Off). During ground turnaround, pilot seal extrusion is commonly indicated by slow gaseous nitrogen (GN2) main valve opening times (greater than 38 ms) or slow water main valve opening response times (greater than 33 ms). Poppet lift tests and visual inspection can also detect pilot seal extrusion during ground servicing; however, direct metrology on the pilot seat assembly provides the most quantitative and accurate means of identifying extrusion. Minimizing PRCS fuel valve pilot seal extrusion has become an important issue in the effort to improve PRCS reliability and reduce associated life cycle costs.

  18. Analysis of the STS-126 Flow Control Valve Structural-Acoustic Coupling Failure

    NASA Technical Reports Server (NTRS)

    Jones, Trevor M.; Larko, Jeffrey M.; McNelis, Mark E.

    2010-01-01

    During the Space Transportation System mission STS-126, one of the main engine's flow control valves incurred an unexpected failure. A section of the valve broke off during liftoff. It is theorized that an acoustic mode of the flowing fuel, coupled with a structural mode of the valve, causing a high cycle fatigue failure. This report documents the analysis efforts conducted in an attempt to verify this theory. Hand calculations, computational fluid dynamics, and finite element methods are all implemented and analyses are performed using steady-state methods in addition to transient analysis methods. The conclusion of the analyses is that there is a critical acoustic mode that aligns with a structural mode of the valve

  19. The development of a microprocessor-controlled linearly-actuated valve assembly

    NASA Technical Reports Server (NTRS)

    Wall, R. H.

    1984-01-01

    The development of a proportional fluid control valve assembly is presented. This electromechanical system is needed for space applications to replace the current proportional flow controllers. The flow is controlled by a microprocessor system that monitors the control parameters of upstream pressure and requested volumetric flow rate. The microprocessor achieves the proper valve stem displacement by means of a digital linear actuator. A linear displacement sensor is used to measure the valve stem position. This displacement is monitored by the microprocessor system as a feedback signal to close the control loop. With an upstream pressure between 15 and 47 psig, the developed system operates between 779 standard CU cm/sec (SCCS) and 1543 SCCS.

  20. Colorado Air Quality Control Regulations and Ambient Air Quality Standards.

    ERIC Educational Resources Information Center

    Colorado State Dept. of Health, Denver. Div. of Air Pollution Control.

    Regulations and standards relative to air quality control in Colorado are defined in this publication. Presented first are definitions of terms, a statement of intent, and general provisions applicable to all emission control regulations adopted by the Colorado Air Pollution Control Commission. Following this, three regulations are enumerated: (1)…

  1. "Non-Reflective" Boundary Design via Remote Sensing and PID Control Valve

    SciTech Connect

    Zhang, Qin Fen; Karney, Professor Byran W.; Pejovic, Dr. Stanislav

    2011-01-01

    This paper develops the concept of a nonreflective (or semireflective) boundary condition using the combination of a remote sensor and a control system to modulate a relief valve. The essential idea is to sense the pressure change at a remote location and then to use the measured data to adjust the opening of an active control valve at the end of the line to eliminate or attenuate the wave reflections at the valve, thus controlling system transient pressures. This novel idea is shown here through numerical simulation to have considerable potential for transient protection. Using this model, wave reflections and resonance can be effectively eliminated for frictionless pipelines or initial no-flow conditions and can be better controlled in more realistic pipelines for a range of transient disturbances. In addition, the features of even-order harmonics and nonreflective boundary conditions during steady oscillation, obtained through time domain transient analysis, are verified by hydraulic impedance analysis in the frequency domain.

  2. Product Guide/1972 [Air Pollution Control Association].

    ERIC Educational Resources Information Center

    Journal of the Air Pollution Control Association, 1971

    1971-01-01

    Reprinted in this pamphlet is the fifth annual directory of air pollution control products as compiled in the "Journal of the Air Pollution Control Association" for December, 1971. The 16-page guide lists manufacturers of emission control equipment and air pollution instrumentation under product classifications as derived from McGraw-Hill's "Air…

  3. Performance characteristics of a turbo expander substituted for expansion valve on air-conditioner

    SciTech Connect

    Cho, Soo-Yong; Cho, Chong-Hyun; Kim, Chaesil

    2008-09-15

    An experimental study is conducted on a small turbo expander which could be applied to the expansion process in place of expansion valves in refrigerator or air-conditioner to improve the cycle efficiency by recovering energy from the throttling process. The operating gas is HFC134a and the maximum cooling capacity of experiment apparatus is 32.7 kW. Four different turbo expanders are tested to find the performance characteristics of the turbo expander when they operate at a low partial admission rate. The partial admission rate is 1.70% or 2.37, and expanders are operated in the supersonic flow. In the experiment, pressure and temperature are measured at 10 different locations in the experimental apparatus. In addition to these measurements, output power at the turbo expander is measured through a generator installed on a rotor shaft with the rotational speed. Performance data of the turbo expander are obtained at many part load operations by adjusting the output power of the generator. A maximum of 15.8% total-to-static efficiency is obtained when the pressure ratio and the partial admission ratio are 2.37 and 1.70%, respectively. Experimental results show that the optimal velocity ratio decreases when the pressure ratio is decreased, and peak efficiencies, which are obtained at locally maximized efficiency depending on the operating condition, vary linearly against the subcooling temperature or the pressure ratio. (author)

  4. Controlled transport of superparamagnetic beads with spin-valves

    NASA Astrophysics Data System (ADS)

    Altman, Wendy R.; Moreland, John; Russek, Stephen E.; Han, Bruce W.; Bright, Victor M.

    2011-10-01

    Trapping, release, and transport of individual, or ensembles of, 2.8 μm superparamagnetic beads (SPB) functionalized with streptavidin were demonstrated with an addressable array of spin-valve (SV) traps integrated into a microfluidic channel. The linear array consists of two staggered lines of 1 μm × 8 μm SVs toggled "on" or "off" with 10 ms and 150 mA or -100 mA current pulses, respectively. The SPB is trapped when the SV is "on" and released or ignored when the SV is "off". This "switchable permanent magnet" offers a low power alternative to other precision microfluidic transport devices.

  5. The controller, aviation medicine and air safety.

    PubMed

    Watkin, B L

    1983-03-01

    Aviation medicine has researched many important facts on pilots, but little on direct relationships between controllers, aviation medicine and air safety. The unsuspecting flying public accepts a 'blind faith' in aircraft and pilots, unaware that aircraft are controlled within 'suspect' ATC systems. The deceptive simplicity of controlling air traffic in apparently limitless skies belies the complexity of man-machine ATC systems operated in ever-crowded airspace, sometimes with antiquated equipment and indifferent communications. The indivisible operational controller/pilot team strives to meet similar ICAO medical standards and operate within the limitations of non-standardised recorded air traffic. Despite controllers' intensive stress at air disasters and 'almost' air disasters, air traffic must continually be controlled for air safety; but, countless human lives (and insurance dollars) saved are possibly camouflaged within the smoke screen of ATC. In New Zealand aviation, the Accident Compensation Corporation is statutorily responsible for air-safety, but accident investigators need controllers' expertise. Has a climate of complacency evolved towards air safety such that New Zealand's Erebus and other air disasters could have been avoided? Controllers are that crucial link in aviation with personal medical fitness vital to the air safety of the unsuspecting flying public. Controllers' dedicated aim for complete air safety in ATC shall benefit from greater understanding within aviation medicine and in-depth medical research.

  6. Application of control valves and balancing valves in a variable-flow hydronic system

    SciTech Connect

    Hegberg, R.A.

    1998-10-01

    In a hydronic system design for an HVAC system with load terminals for providing heating or cooling to a building, it is desirable to provide a variable water flow under command of the space temperature/humidity control at each load terminal. This paper discusses the design of a variable-speed pumping system with proportional control.

  7. Magnetic timing valves for fluid control in paper-based microfluidics.

    PubMed

    Li, Xiao; Zwanenburg, Philip; Liu, Xinyu

    2013-07-01

    Multi-step analytical tests, such as an enzyme-linked immunosorbent assay (ELISA), require delivery of multiple fluids into a reaction zone and counting the incubation time at different steps. This paper presents a new type of paper-based magnetic valves that can count the time and turn on or off a fluidic flow accordingly, enabling timed fluid control in paper-based microfluidics. The timing capability of these valves is realized using a paper timing channel with an ionic resistor, which can detect the event of a solution flowing through the resistor and trigger an electromagnet (through a simple circuit) to open or close a paper cantilever valve. Based on this principle, we developed normally-open and normally-closed valves with a timing period up to 30.3 ± 2.1 min (sufficient for an ELISA on paper-based platforms). Using the normally-open valve, we performed an enzyme-based colorimetric reaction commonly used for signal readout of ELISAs, which requires a timed delivery of an enzyme substrate to a reaction zone. This design adds a new fluid-control component to the tool set for developing paper-based microfluidic devices, and has the potential to improve the user-friendliness of these devices.

  8. Control performances of a piezoactuator direct drive valve system at high temperatures with thermal insulation

    NASA Astrophysics Data System (ADS)

    Han, Yung-Min; Han, Chulhee; Kim, Wan Ho; Seong, Ho Yong; Choi, Seung-Bok

    2016-09-01

    This technical note presents control performances of a piezoactuator direct drive valve (PDDV) operated at high temperature environment. After briefly discussing operating principle and mechanical dimensions of the proposed PDDV, an appropriate size of the PDDV is manufactured. As a first step, the temperature effect on the valve performance is experimentally investigated by measuring the spool displacement at various temperatures. Subsequently, the PDDV is thermally insulated using aerogel and installed in a large-size heat chamber in which the pneumatic-hydraulic cylinders and sensors are equipped. A proportional-integral-derivative feedback controller is then designed and implemented to control the spool displacement of the valve system. In this work, the spool displacement is chosen as a control variable since it is directly related to the flow rate of the valve system. Three different sinusoidal displacements with different frequencies of 1, 10 and 50 Hz are used as reference spool displacement and tracking controls are undertaken up to 150 °C. It is shown that the proposed PDDV with the thermal insulation can provide favorable control responses without significant tracking errors at high temperatures.

  9. The effectiveness of a double-stem injection valve in controlling combustion in a compression-ignition engine

    NASA Technical Reports Server (NTRS)

    Spanogle, J A; Whitney, E G

    1931-01-01

    An investigation was made to determine to what extent the rates of combustion in a compression-ignition engine can be controlled by varying the rates of fuel injection. The tests showed that the double-stem valve operated satisfactorily under all normal injection conditions; the rate of injection has a definite effect on the rate of combustion; the engine performance with the double-stem valve was inferior to that obtained with a single-stem valve; and the control of injection rates permitted by an injection valve of two stages of discharge is not sufficient to effect the desired rates of combustion.

  10. AIR POLLUTION CONTROL TECHNOLOGIES (CHAPTER 65)

    EPA Science Inventory

    The chapter discusses the use of technologies for reducing air pollution emissions from stationary sources, with emphasis on the control of combustion gen-erated air pollution. Major stationary sources include utility power boilers, industrial boilers and heaters, metal smelting ...

  11. Performance Evaluation of a High Bandwidth Liquid Fuel Modulation Valve for Active Combustion Control

    NASA Technical Reports Server (NTRS)

    Saus, Joseph R.; DeLaat, John C.; Chang, Clarence T.; Vrnak, Daniel R.

    2012-01-01

    At the NASA Glenn Research Center, a characterization rig was designed and constructed for the purpose of evaluating high bandwidth liquid fuel modulation devices to determine their suitability for active combustion control research. Incorporated into the rig s design are features that approximate conditions similar to those that would be encountered by a candidate device if it were installed on an actual combustion research rig. The characterized dynamic performance measures obtained through testing in the rig are planned to be accurate indicators of expected performance in an actual combustion testing environment. To evaluate how well the characterization rig predicts fuel modulator dynamic performance, characterization rig data was compared with performance data for a fuel modulator candidate when the candidate was in operation during combustion testing. Specifically, the nominal and off-nominal performance data for a magnetostrictive-actuated proportional fuel modulation valve is described. Valve performance data were collected with the characterization rig configured to emulate two different combustion rig fuel feed systems. Fuel mass flows and pressures, fuel feed line lengths, and fuel injector orifice size was approximated in the characterization rig. Valve performance data were also collected with the valve modulating the fuel into the two combustor rigs. Comparison of the predicted and actual valve performance data show that when the valve is operated near its design condition the characterization rig can appropriately predict the installed performance of the valve. Improvements to the characterization rig and accompanying modeling activities are underway to more accurately predict performance, especially for the devices under development to modulate fuel into the much smaller fuel injectors anticipated in future lean-burning low-emissions aircraft engine combustors.

  12. Investigation of effect of reduction of valve friction in a power control system by use of a vibrator

    NASA Technical Reports Server (NTRS)

    Phillips, William H

    1955-01-01

    Brief ground tests were made to determine the effect of reduction of valve friction in a power control system of a fighter airplane by use of a vibrator. The vibrator was found to be an effective means of overcoming adverse effects of valve friction on the control characteristics.

  13. Internal crankcase ventilation system with easily accessible PCV valve

    SciTech Connect

    Balsley, R.L.

    1986-07-29

    A crankcase ventilation system is described having a flow limiting PCV valve and means defining and internal passage between a crankcase and a cylinder charge induction means of an engine, the system comprising an engine valve cover forming a part of the internal passage defining means and having an exterior wall, a cavity in the cover wall and forming a portion of the internal passage, the wall further including valve mounting means surrounding the passage and receiving the valve and a valve body seal in position to control flow through the mounting means and passage and an opening through the wall to the housing exterior and generally opposite the mounting means for removing and replacing a valve on the mounting means, and closure means normally closing the opening and preventing air leakage therethrough into the induction system, the closure means engaging the valve to maintain its installed position within the wall cavity and being openable to permit removal of the PCV valve.

  14. Air Pollution and Control Legislation in India

    NASA Astrophysics Data System (ADS)

    P Bhave, Prashant; Kulkarni, Nikhil

    2015-09-01

    Air pollution in urban areas arises from multiple sources, which may vary with location and developmental activities. Anthropogenic activities as rampant industrialization, exploitation and over consumption of natural resources, ever growing population size are major contributors of air pollution. The presented review is an effort to discuss various aspects of air pollution and control legislation in India emphasizing on the history, present scenario, international treaties, gaps and drawbacks. The review also presents legislative controls with judicial response to certain landmark judgments related to air pollution. The down sides related to enforcement mechanism for the effective implementation of environmental laws for air pollution control have been highlighted.

  15. Pneumatic shutoff and time-delay valve operates at controlled rate

    NASA Technical Reports Server (NTRS)

    Horning, J. L.; Tomlinson, L. E.

    1966-01-01

    Shutoff and time delay valve, which incorporates a metering spool that moves at constant velocity under pneumatic pressure and spring compression, increases fluid-flow area at a uniform rate. Diaphragm areas, control cavity volume, and bleed-orifice size may be varied to give any desired combination of time delay and spool travel time.

  16. Butterfly valve with metal seals controls flow of hydrogen from cryogenic through high temperatures

    NASA Technical Reports Server (NTRS)

    Johnson, L. D.

    1967-01-01

    Butterfly valve with metal seals operates over a temperature range of minus 423 degrees to plus 440 degrees F with hydrogen as a medium and in a radiation environment. Media flow is controlled by an internal butterfly disk which is rotated by an actuation shaft.

  17. Low cost forged Y-pattern valves control hot corrosive/erosive gases

    SciTech Connect

    Gaines, A.

    1987-06-01

    The Morgantown Energy Technology Center in Morgantown, West Virginia is a research facility of the US Department of Energy (DOE) that does research on fossil fuels utilization and conversion to provide improved and environmentally acceptable energy sources. One area of investigation in the Morgantown facility is the use of gaseous fuels derived from coal from fluidized-bed and fixed-bed gasification technologies. The corrosive and slightly erosive gases and vapors at about 1000F and from 100 to 300 psi are treated in an experimental desulfurization unit to produce fuel gas with greatly enhanced environmental characteristics. The valves in use were constructed of Type 347 stainless steel, a stabilized version of 316 SS, and cost about $6000 for the 2'' size and about $4000 for the 1'' size. Despite the high cost, the valve sometimes became difficult or impossible to operate due to metal failures. The Technology Center had a number of new Class 1500 Y-pattern (angle-style) globe valves in inventory. The control valve body and bonnet are forged chrome moly steel (ASTM-H182-F22), the stem assembly is a 13% chrome alloy with an erosion resistant hard faced disc, and the seat ring is a cobalt-base alloy fused in place as an integral part of the body. Stem packing as an either wire inserted molded asbestos or Grafoil flexible graphite. The Y-pattern globe valves in 1 and 2'' sizes, which were judged potentially suitable and on hand, were installed in the experimental desulfization unit as well as in the connecting hot gas piping system to a new coal gasification process. The Class 1500 Y-pattern valves have provided reliable control of the hot corrosive and erosive gas streams with very little maintenance.

  18. Innovative, High-Pressure, Cryogenic Control Valve: Short Face-to-Face, Reduced Cost

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A control valve that can throttle high-pressure cryogenic fluid embodies several design features that distinguish it over conventional valves designed for similar applications. Field and design engineers worked together to create a valve that would simplify installation, trim changes, and maintenance, thus reducing overall cost. The seals and plug stem packing were designed to perform optimally in cryogenic temperature ranges. Unlike conventional high-pressure cryogenic valves, the trim size can be changed independent of the body. The design feature that provides flexibility for changing the trim is a split body. The body is divided into an upper and a lower section with the seat ring sandwiched in between. In order to maintain the plug stem packing at an acceptable sealing temperature during cryogenic service, heat-exchanging fins were added to the upper body section. The body is made of stainless steel. The seat ring is made of a nickel-based alloy having a coefficient of thermal expansion less than that of the body material. Consequently, when the interior of the valve is cooled cryogenically, the body surrounding the seat ring contracts more than the seat ring. This feature prevents external leakage at the body-seat joint. The seat ring has been machined to have small, raised-face sealing surfaces on both sides of the seal groove. These sealing surfaces concentrate the body bolt load over a small area, thereby preventing external leakage. The design of the body bolt circle is different from that of conventional highpressure control valves. Half of the bolts clamp the split body together from the top, and half from the bottom side. This bolt-circle design allows a short, clean flow path, which minimizes frictional flow losses. This bolt-circle design also makes it possible to shorten the face-toface length of the valve, which is 25.5 in. (65 cm). In contrast, a conventional, high-pressure control valve face-to-face dimension may be greater than 40 in. (>1 m

  19. Mechanotransduction, PROX1, and FOXC2 cooperate to control connexin37 and calcineurin during lymphatic-valve formation.

    PubMed

    Sabine, Amélie; Agalarov, Yan; Maby-El Hajjami, Hélène; Jaquet, Muriel; Hägerling, René; Pollmann, Cathrin; Bebber, Damien; Pfenniger, Anna; Miura, Naoyuki; Dormond, Olivier; Calmes, Jean-Marie; Adams, Ralf H; Mäkinen, Taija; Kiefer, Friedemann; Kwak, Brenda R; Petrova, Tatiana V

    2012-02-14

    Lymphatic valves are essential for efficient lymphatic transport, but the mechanisms of early lymphatic-valve morphogenesis and the role of biomechanical forces are not well understood. We found that the transcription factors PROX1 and FOXC2, highly expressed from the onset of valve formation, mediate segregation of lymphatic-valve-forming cells and cell mechanosensory responses to shear stress in vitro. Mechanistically, PROX1, FOXC2, and flow coordinately control expression of the gap junction protein connexin37 and activation of calcineurin/NFAT signaling. Connexin37 and calcineurin are required for the assembly and delimitation of lymphatic valve territory during development and for its postnatal maintenance. We propose a model in which regionally increased levels/activation states of transcription factors cooperate with mechanotransduction to induce a discrete cell-signaling pattern and morphogenetic event, such as formation of lymphatic valves. Our results also provide molecular insights into the role of endothelial cell identity in the regulation of vascular mechanotransduction.

  20. Scissor thrust valve actuator

    DOEpatents

    DeWall, Kevin G.; Watkins, John C; Nitzel, Michael E.

    2006-08-29

    Apparatus for actuating a valve includes a support frame and at least one valve driving linkage arm, one end of which is rotatably connected to a valve stem of the valve and the other end of which is rotatably connected to a screw block. A motor connected to the frame is operatively connected to a motor driven shaft which is in threaded screw driving relationship with the screw block. The motor rotates the motor driven shaft which drives translational movement of the screw block which drives rotatable movement of the valve driving linkage arm which drives translational movement of the valve stem. The valve actuator may further include a sensory control element disposed in operative relationship with the valve stem, the sensory control element being adapted to provide control over the position of the valve stem by at least sensing the travel and/or position of the valve stem.

  1. Air gun wounding and current UK laws controlling air weapons.

    PubMed

    Bruce-Chwatt, Robert Michael

    2010-04-01

    Air weapons whether rifles or pistols are, potentially, lethal weapons. The UK legislation is complex and yet little known to the public. Hunting with air weapons and the laws controlling those animals that are permitted to be shot with air weapons is even more labyrinthine due to the legal power limitations on the possession of air weapons. Still relatively freely available by mail order or on the Internet, an increasing number of deaths have been reported from the misuse of air weapons or accidental discharges. Ammunition for air weapons has become increasingly sophisticated, effective and therefore increasingly dangerous if misused, though freely available being a mere projectile without a concomitant cartridge containing a propellant and an initiator.

  2. Thermostatic Valves Containing Silicone-Oil Actuators

    NASA Technical Reports Server (NTRS)

    Bhandari, Pradeep; Birur, Gajanana C.; Bame, David P.; Karlmann, Paul B.; Prina, Mauro; Young, William; Fisher, Richard

    2009-01-01

    Flow-splitting and flow-mixing thermally actuated spool valves have been developed for controlling flows of a heat-transfer fluid in a temperature-regulation system aboard the Mars Science Laboratory (MSL) rover. Valves like these could also be useful in terrestrial temperature-regulation systems, including automobile air-conditioning systems and general refrigeration systems. These valves are required to provide smoother actuation over a wider temperature range than the flow-splitting, thermally actuated spool valves used in the Mars Explorer Rover (MER). Also, whereas the MER valves are unstable (tending to oscillate) in certain transition temperature ranges, these valves are required not to oscillate. The MER valves are actuated by thermal expansion of a wax against spring-loaded piston rods (as in common automotive thermostats). The MSL valves contain similar actuators that utilize thermal expansion of a silicone oil, because silicone-oil actuators were found to afford greater and more nearly linear displacements, needed for smoother actuation, over the required wider temperature range. The MSL valves also feature improved spool designs that reflect greater understanding of fluid dynamics, consideration of pressure drops in valves, and a requirement for balancing of pressures in different flow branches.

  3. Control valves and cascades for the first stages of turbines with ultrasupercritical steam parameters

    NASA Astrophysics Data System (ADS)

    Zaryankin, A. E.; Rogalev, N. D.; Rogalev, A. N.; Garanin, I. V.; Osipov, S. K.; Grigoriev, E. Yu.

    2016-06-01

    This paper considers the problems that will unavoidably be encountered in the creation of new-generation turbines operated at ultrasupercritical initial steam parameters, namely, the development of new control and shutoff valves, the reduction of end energy losses in blade cascades and steam leaks in high-pressure cylinders (HPCs), the elimination of effect produced by regenerative steam bleedoffs on the afterextraction stage, the cooling of a blade cascade, etc. Some possible solutions are given for the two first of the listed problems. The conclusion about the need for the transition to new-generation control valves in the development of new advanced steam turbines with ultrasupercritical initial steam parameters has been made. From the viewpoint of their design, the considered new-generation valves differ from the known contemporary constructions by a shaped axially symmetric confusor channel and perforated zones on the streamlined spool surface and the inlet diffuser saddle part. The analysis of the vibration behavior of new-generation valves has demonstrated a decrease in the dynamic loads acting on their stems. To reduce the end energy losses in nozzle or blade cascades with small aspect ratios, it is proposed to use finned shrouds in the interblade channels. The cross section of fins has a triangular profile, and their height must be comparable with the thickness of the boundary layer in the outlet cross section of a cascade and, provisionally, be smaller than 8% of the cascade chord.

  4. Controls on ostracod valve geochemistry: Part 2. Carbon and oxygen isotope compositions

    NASA Astrophysics Data System (ADS)

    Decrouy, Laurent; Vennemann, Torsten Walter; Ariztegui, Daniel

    2011-11-01

    The stable carbon and oxygen isotope compositions of fossil ostracods are powerful tools to estimate past environmental and climatic conditions. The basis for such interpretations is that the calcite of the valves reflects the isotopic composition of water and its temperature of formation. However, calcite of ostracods is known not to form in isotopic equilibrium with water and different species may have different offsets from inorganic precipitates of calcite formed under the same conditions. To estimate the fractionation during ostracod valve calcification, the oxygen and carbon isotope compositions of 15 species living in Lake Geneva were related to their autoecology and the environmental parameters measured during their growth. The results indicate that: (1) Oxygen isotope fractionation is similar for all species of Candoninae with an enrichment in 18O of more than 3‰ relative to equilibrium values for inorganic calcite. Oxygen isotope fractionation for Cytheroidea is less discriminative relative to the heavy oxygen, with enrichments in 18O for these species of 1.7 to 2.3‰. Oxygen isotope fractionations for Cyprididae are in-between those of Candoninae and Cytheroidea. The difference in oxygen isotope fractionation between ostracods and inorganic calcite has been interpreted as resulting from a vital effect. (2) Comparison with previous work suggests that oxygen isotope fractionation may depend on the total and relative ion content of water. (3) Carbon isotope compositions of ostracod valves are generally in equilibrium with DIC. The specimens' δ 13C values are mainly controlled by seasonal variations in δ 13C DIC of bottom water or variation thereof in sediment pore water. (4) Incomplete valve calcification has an effect on carbon and oxygen isotope compositions of ostracod valves. Preferential incorporation of CO32- at the beginning of valve calcification may explain this effect. (5) Results presented here as well as results from synthetic carbonate

  5. Dual stage check valve

    NASA Technical Reports Server (NTRS)

    Whitten, D. E. (Inventor)

    1973-01-01

    A dual stage seat valve head arrangement is described which consists of a primary sealing point located between a fixed orifice seat and a valve poppet, and a secondary sealing point between an orifice poppet and a valve poppet. Upstream of the valve orifice is a flexible, convoluted metal diaphragm attached to the orifice poppet. Downstream of the valve orifice, a finger spring exerts a force against the valve poppet, tending to keep the valve in a closed position. The series arrangement of a double seat and poppet is able to tolerate small particle contamination while minimizing chatter by controlling throttling or metering across the secondary seat, thus preserving the primary sealing surface.

  6. Turbocharger control system

    SciTech Connect

    Yogo, K.; Nomura, I.

    1987-04-21

    A turbocharger control system is described utilizing a carburetor system. This system includes a carburetor having an air-fuel induction passage, a fuel supply passage for supplying fuel to the air-fuel induction passage, and a turbocharger compressor impeller disposed upstream of a throttle valve and compressing an air-fuel mixture flow delivered to an engine intake manifold. The turbocharger control system comprises: a surge tank provided in the intake manifold; an air control valve including means for controlling an air bleeding amount supplied to the air induction passage in response to changes in pressure of the surge tank. The air control valve further comprises a valve housing having an end wall and including a first, second and third chamber formed therein. A diaphragm has a valve member for controlling communication between the second chamber and the third chamber in response to a pressure existing in the first chamber, a spring biasing the diaphragm in a direction such that the valve member is maintained in a closed position against the pressure in the first chamber. A valve seat plate is in contact with the valve member. The first chamber is connected with the surge tank and the second chamber is connected with the fuel supply passage, and the third chamber is connected with atmosphere. The first chamber is defined by a valve housing of the air control valve, the end wall and the diaphragm and the valve member has a tapered form.

  7. Air Pollution and Its Control, Second Edition.

    ERIC Educational Resources Information Center

    Sproull, Wayne T.

    A concise appraisal of our contemporary status and future prospects with regard to air pollution and its control are offered in this text for concerned laymen. What air pollution is, how it endangers health, the cost of controlling it, what is being done about it now, and what should be done are some of the basic questions considered. Topics cover…

  8. Topics in Air Pollution Control (SI: 428).

    ERIC Educational Resources Information Center

    Rampacek, Anne; Chaput, Linda

    This course provides information about air pollution control efforts since the passage of the Clean Air Act and places in perspective various issues that have arisen since passage of the act--significant deterioration, maintenance of standards, indirect source review, and transportation controls. Court decisions affecting these issues are cited…

  9. Career Guide for Air Pollution Control

    ERIC Educational Resources Information Center

    Baldwin, Lionel V.

    1975-01-01

    This guide to career opportunities in air pollution control includes resource information in this area and provides a listing of colleges and universities offering environmental science programs. The guide was prepared by the S-11 Education and Training Committee of the Air Pollution Control Association. (Author/BT)

  10. Automatic speech recognition in air traffic control

    NASA Technical Reports Server (NTRS)

    Karlsson, Joakim

    1990-01-01

    Automatic Speech Recognition (ASR) technology and its application to the Air Traffic Control system are described. The advantages of applying ASR to Air Traffic Control, as well as criteria for choosing a suitable ASR system are presented. Results from previous research and directions for future work at the Flight Transportation Laboratory are outlined.

  11. Control performance of an electrorheological valve based vehicle anti-lock brake system, considering the braking force distribution

    NASA Astrophysics Data System (ADS)

    Choi, S. B.; Lee, T. H.; Lee, Y. S.; Han, M. S.

    2005-12-01

    This paper presents the braking control performance of a vehicle anti-lock brake system featuring an electrorheological (ER) fluid. As a first step, a cylindrical type of ER valve is devised and its pressure controllability is experimentally confirmed. Then, a hydraulic booster for amplifying the field-dependent pressure drop obtained from the ER valve is constructed and its pressure amplification is demonstrated by presenting the pressure tracking control performance. Subsequently, the governing equation of the rear wheel model is derived by considering the braking force distribution, and a sliding mode controller for achieving the desired slip rate is designed. The controller is then realized through the hardware-in-the-loop simulation method and controlled responses are presented in the time domain. In addition, computer animations for the braking performance under unladen and laden conditions are presented, and a comparison of the proportioning valve and the proposed ER valve pressure modulator is made.

  12. Fast acting check valve

    NASA Technical Reports Server (NTRS)

    Perkins, Gerald S. (Inventor)

    1979-01-01

    A check valve which closes more rapidly to prevent wearing of the valve seat and of the valve member that seals thereagainst, including a solenoid or other actuator that aids the normal spring to quickly close the valve at approximately the time when downpath fluid flow would stop, the actuator then being deenergized. The control circuit that operates the actuator can include a pair of pressure sensors sensing pressure both upstream and downstream from the valve seat. Where the valve is utilized to control flow to or from a piston pump, energization of the actuator can be controlled by sensing when the pump piston reaches its extreme of travel.

  13. Static Flow Characteristics of a Mass Flow Injecting Valve

    NASA Technical Reports Server (NTRS)

    Mattern, Duane; Paxson, Dan

    1995-01-01

    A sleeve valve is under development for ground-based forced response testing of air compression systems. This valve will be used to inject air and to impart momentum to the flow inside the first stage of a multi-stage compressor. The valve was designed to deliver a maximum mass flow of 0.22 lbm/s (0.1 kg/s) with a maximum valve throat area of 0.12 sq. in (80 sq. mm), a 100 psid (689 KPA) pressure difference across the valve and a 68 F, (20 C) air supply. It was assumed that the valve mass flow rate would be proportional to the valve orifice area. A static flow calibration revealed a nonlinear valve orifice area to mass flow relationship which limits the maximum flow rate that the valve can deliver. This nonlinearity was found to be caused by multiple choking points in the flow path. A simple model was used to explain this nonlinearity and the model was compared to the static flow calibration data. Only steady flow data is presented here. In this report, the static flow characteristics of a proportionally controlled sleeve valve are modelled and validated against experimental data.

  14. 42. VALVEHOUSE FOR NEEDLE VALVE OUTLET WORKS ON GALLERY 2, ...

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

    42. VALVEHOUSE FOR NEEDLE VALVE OUTLET WORKS ON GALLERY 2, SHOWING OVERHEAD SERVICE CRANE AT CENTER. NOTE NEEDLE VALVE AIR VENTS AND GAUGES AT RIGHT, NEXT TO CONTROL PEDESTAL. VIEW TO EAST. - Owyhee Dam, Across Owyhee River, Nyssa, Malheur County, OR

  15. Space Shuttle Main Propulsion System Gaseous Hydrogen Flow Control Valve Poppet Failure

    NASA Technical Reports Server (NTRS)

    Zeitler, Rick

    2010-01-01

    The presentation provides background information pertinent to the MPS GH2 Flow Control Valve Poppet failure which occurred on the Space Shuttle Endeavour during STS-126 flight. The presentation provides general MPS system operating information which is pertinent to understanding the failure causes and affects. The presentation provides additional background information on the operating environment in which the FCV functions and basic design history of the flow control valve. The presentation provides an overview of the possible flight failure modes and a brief summary of the flight rationale which was developed for this failure event. This presentation is an introductory presentation to 3 other speakers at the conference who will be speaking on M&P aspects of the investigation, non destructive inspection techniques development, and particle impact testing.

  16. Remote manual operator for space station intermodule ventilation valve

    NASA Technical Reports Server (NTRS)

    Guyaux, James R.

    1996-01-01

    The Remote Manual Operator (RMO) is a mechanism used for manual operation of the Space Station Intermodule Ventilation (IMV) valve and for visual indication of valve position. The IMV is a butterfly-type valve, located in the ventilation or air circulation ducts of the Space Station, and is used to interconnect or isolate the various compartments. The IMV valve is normally operated by an electric motor-driven actuator under computer or astronaut control, but it can also be operated manually with the RMO. The IMV valve RMO consists of a handle with a deployment linkage, a gear-driven flexible shaft, and a linkage to disengage the electric motor actuator during manual operation. It also provides visual indication of valve position. The IMV valve RMO is currently being prepared for qualification testing.

  17. A hybrid disturbance rejection control solution for variable valve timing system of gasoline engines.

    PubMed

    Xie, Hui; Song, Kang; He, Yu

    2014-07-01

    A novel solution for electro-hydraulic variable valve timing (VVT) system of gasoline engines is proposed, based on the concept of active disturbance rejection control (ADRC). Disturbances, such as oil pressure and engine speed variations, are all estimated and mitigated in real-time. A feed-forward controller was added to enhance the performance of the system based on a simple and static first principle model, forming a hybrid disturbance rejection control (HDRC) strategy. HDRC was validated by experimentation and compared with an existing manually tuned proportional-integral (PI) controller. The results show that HDRC provided a faster response and better tolerance of engine speed and oil pressure variations.

  18. Electrical servo actuator bracket. [fuel control valves on jet engines

    NASA Technical Reports Server (NTRS)

    Sawyer, R. V. (Inventor)

    1981-01-01

    An electrical servo actuator is mounted on a support arm which is allowed to pivot on a bolt through a fixed mounting bracket. The actuator is pivotally connected to the end of the support arm by a bolt which has an extension allowed to pass through a slot in the fixed mounting bracket. An actuator rod extends from the servo actuator to a crank arm which turns a control shaft. A short linear thrust of the rod pivots the crank arm through about 90 for full-on control with the rod contracted into the servo actuator, and full-off control when the rod is extended from the actuator. A spring moves the servo actuator and actuator rod toward the control crank arm once the actuator rod is fully extended in the full-off position. This assures the turning of the control shaft to a full-off position. A stop bolt and slot are provided to limit pivot motion. Once fully extended, the spring pivots the motion.

  19. Variance Design and Air Pollution Control

    ERIC Educational Resources Information Center

    Ferrar, Terry A.; Brownstein, Alan B.

    1975-01-01

    Air pollution control authorities were forced to relax air quality standards during the winter of 1972 by granting variances. This paper examines the institutional characteristics of these variance policies from an economic incentive standpoint, sets up desirable structural criteria for institutional design and arrives at policy guidelines for…

  20. Collegiate Aviation and FAA Air Traffic Control.

    ERIC Educational Resources Information Center

    Ruiz, Jose R.; Ruiz, Lorelei E.

    2003-01-01

    Based on a literature review this article describes the Air Traffic-Collegiate Training Initiative (AT-CTI) program, including objectives, the process by which postsecondary institutes become affiliated, advantages of affiliation, and the recruitment and employment of air traffic control graduates by the Federal Aviation Administration. (Contains…

  1. Expanding Robust HCCI Operation with Advanced Valve and Fuel Control Technologies

    SciTech Connect

    Szybist, J. P.; Confer, K.

    2012-09-11

    Delphi Automotive Systems and ORNL established this CRADA to advance the commercialization potential of the homogeneous charge compression ignition (HCCI) advanced combustion strategy for gasoline engine platforms. HCCI combustion has been shown by others to produce high diesel-like efficiency on a gasoline engine platform while simultaneously producing low NOX and particulate matter emissions. However, the commercialization barriers that face HCCI combustion are significant, with requirements for a more active engine control system, likely with next-cycle closed-loop feedback control, and with advanced valve train technologies to enable negative valve overlap conditions. In the partnership between Delphi and ORNL, each organization brought a unique and complementary set of skills to the project. Delphi has made a number of breakthroughs with production-intent valve train technologies and controls in recent years to make a part time production-intent HCCI engine plausible. ORNL has extensive knowledge and expertise with HCCI combustion, and also has a versatile research engine with hydraulic valve actuation (HVA) that is useful for guiding production of a cam-based HCCI system. Partnering these knowledge bases and capabilities was essential towards making progress to better understand HCCI combustion and the commercialization barriers that it faces. ORNL and Delphi maintained strong collaboration throughout the project. Meetings were held regularly, with additional reports, presentations, and meetings as necessary to maintain progress. Delphi provided guidance to ORNL regarding operational strategies to investigate on their single-cylinder research engine with HVA and data from their experimental multi-cylinder engine for modeling. ORNL provided single-cylinder engine data and modeling results.

  2. Controlling Indoor Air Pollution from Moxibustion

    PubMed Central

    Lu, Chung-Yen; Kang, Sy-Yuan; Liu, Shu-Hui; Mai, Cheng-Wei; Tseng, Chao-Heng

    2016-01-01

    Indoor air quality (IAQ) control of hospitals plays a critical role in protecting both hospital staffs and patients, particularly those who are highly susceptible to the adverse effects of indoor noxious hazards. However, moxibustion in outpatient departments (OPDs) of traditional Chinese medicine (TCM) may be a source of indoor air pollution in hospitals. Some studies have investigated indoor air pollution during moxibustion in Chinese medicine clinics (CMCs) and moxibustion rooms, demonstrating elevated air pollutants that pose a threat to the health of medical staff and patients. Our study investigated the indoor air pollutants of indoor carbon dioxide (CO2), carbon monoxide (CO), formaldehyde (HCHO), total volatile organic compounds (TVOCs), airborne particulate matter with a diameter of ≤10 µm (PM10) and ≤2.5 µm (PM2.5) during moxibustion in an acupuncture and moxibustion room of the OPD in a hospital in Taipei. To evaluate the different control strategies for indoor air pollution from moxibution, a comparison of air pollutants during moxibution among the methods of using alternative old moxa wools, local exhaust ventilation and an air cleaner was conducted. In this study, burning alternative old moxa wools for moxibustion obviously reduced all gaseous pollutants except for aerosols comparing burning fresh moxa wools. Using local exhaust ventilation reduced most of the aerosols after burning moxa. We also found that using an air cleaner was inefficient for controlling indoor air pollutants, particularly gaseous pollutants. Therefore, combining replacing alternative old moxa wools and local exhaust ventilation could be a suitable design for controlling indoor air pollution during moxibustion therapy. PMID:27331817

  3. Evaluation of a fracture failure mode in the Space Shuttle hydrogen pressurization system flow control valves

    NASA Astrophysics Data System (ADS)

    Hauver, S. E.; Sueme, D. R.

    1992-07-01

    During acceptance testing of the Space Shuttle Endeavor hydrogen flow control valves, which are used in the Orbiter's fuel tank pressurization system, two of the valves experienced fracture of the poppet flange. The poppets are made of 440 C, a high strength, wear-resistant, low ductility, martensitic stainless steel. The investigation which was initiated to determine the cause of these failures is traced. All aspects of the poppet processing that may have introduced a defect were assessed. This included machining, heat treating, passivation, assembly, and test. In addition, several potential failure modes were investigated. The extensive investigation revealed no obvious cause of the failures, but did result in a recommendation for a different material application.

  4. Development and marketing of a prosthetic urinary control valve system

    NASA Technical Reports Server (NTRS)

    Tenney, J. B., Jr.; Rabinowitz, R.; Rogers, D. W.; Harrison, H. N.

    1983-01-01

    An implantable prosthetic for the control of urinary incontinence was developed and marketed. Three phases are presented: bench development studies, animal trials, and human clinical trials. This work was performed under the direction of a Research Team at Rochester General Hospital (RGH). Bench trials were completed on prototype hardware and provided early verification of the device's ability to withstand repeated cyclic testing. Configurational variants were evaluated and a preferred design concept was established. Silicone rubber (medical grade) was selected as the preferred material for the prosthesis.

  5. Controllable 0-π Josephson junctions containing a ferromagnetic spin valve

    NASA Astrophysics Data System (ADS)

    Gingrich, E. C.; Niedzielski, Bethany M.; Glick, Joseph A.; Wang, Yixing; Miller, D. L.; Loloee, Reza; Pratt, W. P., Jr.; Birge, Norman O.

    2016-06-01

    Superconductivity and ferromagnetism are antagonistic forms of order, and rarely coexist. Many interesting new phenomena occur, however, in hybrid superconducting/ferromagnetic systems. For example, a Josephson junction containing a ferromagnetic material can exhibit an intrinsic phase shift of π in its ground state for certain thicknesses of the material. Such `π-junctions' were first realized experimentally in 2001 (refs ,), and have been proposed as circuit elements for both high-speed classical superconducting computing and for quantum computing. Here we demonstrate experimentally that the phase state of a Josephson junction containing two ferromagnetic layers can be toggled between 0 and π by changing the relative orientation of the two magnetizations. These controllable 0-π junctions have immediate applications in cryogenic memory, where they serve as a necessary component to an ultralow power superconducting computer. Such a fully superconducting computer is estimated to be orders of magnitude more energy-efficient than current semiconductor-based supercomputers. Phase-controllable junctions also open up new possibilities for superconducting circuit elements such as superconducting `programmable logic', where they could function in superconducting analogues to field-programmable gate arrays.

  6. Control Techniques for Particulate Air Pollutants.

    ERIC Educational Resources Information Center

    National Air Pollution Control Administration (DHEW), Washington, DC.

    Included is a comprehensive review of the approaches commonly recommended for controlling the sources of particulate air pollution. Not all possible combinations of control techniques that might bring about more stringent control of each individual source are reviewed. The many agricultural, commercial, domestic, industrial, and municipal…

  7. Analysis of Controller Communication in En Route Air Traffic Control.

    ERIC Educational Resources Information Center

    Seamster, Thomas L.; And Others

    To contribute to an understanding of the elements of good air traffic controller communication with the objective of providing recommendations to improve controller communication training, two studies analyzed team communication, ground-air communication, and ground-line communication. The simulated and live traffic analyses examined established…

  8. High-Compression-Ratio; Atkinson-Cycle Engine Using Low-Pressure Direct Injection and Pneumatic-Electronic Valve Actuation Enabled by Ionization Current and Foward-Backward Mass Air Flow Sensor Feedback

    SciTech Connect

    Harold Schock; Farhad Jaberi; Ahmed Naguib; Guoming Zhu; David Hung

    2007-12-31

    This report describes the work completed over a two and one half year effort sponsored by the US Department of Energy. The goal was to demonstrate the technology needed to produce a highly efficient engine enabled by several technologies which were to be developed in the course of the work. The technologies included: (1) A low-pressure direct injection system; (2) A mass air flow sensor which would measure the net airflow into the engine on a per cycle basis; (3) A feedback control system enabled by measuring ionization current signals from the spark plug gap; and (4) An infinitely variable cam actuation system based on a pneumatic-hydraulic valve actuation These developments were supplemented by the use of advanced large eddy simulations as well as evaluations of fuel air mixing using the KIVA and WAVE models. The simulations were accompanied by experimental verification when possible. In this effort a solid base has been established for continued development of the advanced engine concepts originally proposed. Due to problems with the valve actuation system a complete demonstration of the engine concept originally proposed was not possible. Some of the highlights that were accomplished during this effort are: (1) A forward-backward mass air flow sensor has been developed and a patent application for the device has been submitted. We are optimistic that this technology will have a particular application in variable valve timing direct injection systems for IC engines. (2) The biggest effort on this project has involved the development of the pneumatic-hydraulic valve actuation system. This system was originally purchased from Cargine, a Swedish supplier and is in the development stage. To date we have not been able to use the actuators to control the exhaust valves, although the actuators have been successfully employed to control the intake valves. The reason for this is the additional complication associated with variable back pressure on the exhaust valves when

  9. Standing valve

    SciTech Connect

    Coleman, S.B.

    1990-08-28

    This patent discusses an apparatus for removing fluids from a wellbore. It comprises a valve housing fixedly secured to a wellbore tubing string, the housing having perforations and a valve seating surface; a valve stem alignment guide secured to the valve housing; a valve stem adapted for movement in the valve stem alignment guide; and a valve seating device attached to the valve stem and capable of contacting the valve seating surface, thereby preventing fluid flow through the valve housing and past the valve seating surface when the seating device and valve seating surface are in contact.

  10. Variable Valve Actuation

    SciTech Connect

    Jeffrey Gutterman; A. J. Lasley

    2008-08-31

    Many approaches exist to enable advanced mode, low temperature combustion systems for diesel engines - such as premixed charge compression ignition (PCCI), Homogeneous Charge Compression Ignition (HCCI) or other HCCI-like combustion modes. The fuel properties and the quantity, distribution and temperature profile of air, fuel and residual fraction in the cylinder can have a marked effect on the heat release rate and combustion phasing. Figure 1 shows that a systems approach is required for HCCI-like combustion. While the exact requirements remain unclear (and will vary depending on fuel, engine size and application), some form of substantially variable valve actuation is a likely element in such a system. Variable valve actuation, for both intake and exhaust valve events, is a potent tool for controlling the parameters that are critical to HCCI-like combustion and expanding its operational range. Additionally, VVA can be used to optimize the combustion process as well as exhaust temperatures and impact the after treatment system requirements and its associated cost. Delphi Corporation has major manufacturing and product development and applied R&D expertise in the valve train area. Historical R&D experience includes the development of fully variable electro-hydraulic valve train on research engines as well as several generations of mechanical VVA for gasoline systems. This experience has enabled us to evaluate various implementations and determine the strengths and weaknesses of each. While a fully variable electro-hydraulic valve train system might be the 'ideal' solution technically for maximum flexibility in the timing and control of the valve events, its complexity, associated costs, and high power consumption make its implementation on low cost high volume applications unlikely. Conversely, a simple mechanical system might be a low cost solution but not deliver the flexibility required for HCCI operation. After modeling more than 200 variations of the

  11. Smart sensors enable smart air conditioning control.

    PubMed

    Cheng, Chin-Chi; Lee, Dasheng

    2014-01-01

    In this study, mobile phones, wearable devices, temperature and human motion detectors are integrated as smart sensors for enabling smart air conditioning control. Smart sensors obtain feedback, especially occupants' information, from mobile phones and wearable devices placed on human body. The information can be used to adjust air conditioners in advance according to humans' intentions, in so-called intention causing control. Experimental results show that the indoor temperature can be controlled accurately with errors of less than ±0.1 °C. Rapid cool down can be achieved within 2 min to the optimized indoor capacity after occupants enter a room. It's also noted that within two-hour operation the total compressor output of the smart air conditioner is 48.4% less than that of the one using On-Off control. The smart air conditioner with wearable devices could detect the human temperature and activity during sleep to determine the sleeping state and adjusting the sleeping function flexibly. The sleeping function optimized by the smart air conditioner with wearable devices could reduce the energy consumption up to 46.9% and keep the human health. The presented smart air conditioner could provide a comfortable environment and achieve the goals of energy conservation and environmental protection. PMID:24961213

  12. Smart sensors enable smart air conditioning control.

    PubMed

    Cheng, Chin-Chi; Lee, Dasheng

    2014-06-24

    In this study, mobile phones, wearable devices, temperature and human motion detectors are integrated as smart sensors for enabling smart air conditioning control. Smart sensors obtain feedback, especially occupants' information, from mobile phones and wearable devices placed on human body. The information can be used to adjust air conditioners in advance according to humans' intentions, in so-called intention causing control. Experimental results show that the indoor temperature can be controlled accurately with errors of less than ±0.1 °C. Rapid cool down can be achieved within 2 min to the optimized indoor capacity after occupants enter a room. It's also noted that within two-hour operation the total compressor output of the smart air conditioner is 48.4% less than that of the one using On-Off control. The smart air conditioner with wearable devices could detect the human temperature and activity during sleep to determine the sleeping state and adjusting the sleeping function flexibly. The sleeping function optimized by the smart air conditioner with wearable devices could reduce the energy consumption up to 46.9% and keep the human health. The presented smart air conditioner could provide a comfortable environment and achieve the goals of energy conservation and environmental protection.

  13. Smart Sensors Enable Smart Air Conditioning Control

    PubMed Central

    Cheng, Chin-Chi; Lee, Dasheng

    2014-01-01

    In this study, mobile phones, wearable devices, temperature and human motion detectors are integrated as smart sensors for enabling smart air conditioning control. Smart sensors obtain feedback, especially occupants' information, from mobile phones and wearable devices placed on human body. The information can be used to adjust air conditioners in advance according to humans' intentions, in so-called intention causing control. Experimental results show that the indoor temperature can be controlled accurately with errors of less than ±0.1 °C. Rapid cool down can be achieved within 2 min to the optimized indoor capacity after occupants enter a room. It's also noted that within two-hour operation the total compressor output of the smart air conditioner is 48.4% less than that of the one using On-Off control. The smart air conditioner with wearable devices could detect the human temperature and activity during sleep to determine the sleeping state and adjusting the sleeping function flexibly. The sleeping function optimized by the smart air conditioner with wearable devices could reduce the energy consumption up to 46.9% and keep the human health. The presented smart air conditioner could provide a comfortable environment and achieve the goals of energy conservation and environmental protection. PMID:24961213

  14. Research review: Indoor air quality control techniques

    SciTech Connect

    Fisk, W.J.

    1986-10-01

    Techniques for controlling the concentration of radon, formaldehyde, and combustion products in the indoor air are reviewed. The most effective techniques, which are generally based on limiting or reducing indoor pollutant source strengths, can decrease indoor pollutant concentrations by a factor of 3 to 10. Unless the initial ventilation rate is unusually low, it is difficult to reduce indoor pollutant concentrations more than approximately 50% by increasing the ventilation rate of an entire building. However, the efficiency of indoor pollutant control by ventilation can be enhanced through the use of local exhaust ventilation near concentrated sources of pollutants, by minimizing short circuiting of air from supply to exhaust when pollutant sources are dispersed and, in some situations, by promoting a displacement flow of air and pollutants toward the exhaust. Active air cleaning is also examined briefly. Filtration and electrostatic air cleaning for removal of particles from the indoor air are the most practical and effective currently available techniques of air cleaning. 49 refs., 7 figs.

  15. A hybrid approach to modeling and control of vehicle height for electronically controlled air suspension

    NASA Astrophysics Data System (ADS)

    Sun, Xiaoqiang; Cai, Yingfeng; Wang, Shaohua; Liu, Yanling; Chen, Long

    2016-01-01

    The control problems associated with vehicle height adjustment of electronically controlled air suspension (ECAS) still pose theoretical challenges for researchers, which manifest themselves in the publications on this subject over the last years. This paper deals with modeling and control of a vehicle height adjustment system for ECAS, which is an example of a hybrid dynamical system due to the coexistence and coupling of continuous variables and discrete events. A mixed logical dynamical (MLD) modeling approach is chosen for capturing enough details of the vehicle height adjustment process. The hybrid dynamic model is constructed on the basis of some assumptions and piecewise linear approximation for components nonlinearities. Then, the on-off statuses of solenoid valves and the piecewise approximation process are described by propositional logic, and the hybrid system is transformed into the set of linear mixed-integer equalities and inequalities, denoted as MLD model, automatically by HYSDEL. Using this model, a hybrid model predictive controller (HMPC) is tuned based on online mixed-integer quadratic optimization (MIQP). Two different scenarios are considered in the simulation, whose results verify the height adjustment effectiveness of the proposed approach. Explicit solutions of the controller are computed to control the vehicle height adjustment system in realtime using an offline multi-parametric programming technology (MPT), thus convert the controller into an equivalent explicit piecewise affine form. Finally, bench experiments for vehicle height lifting, holding and lowering procedures are conducted, which demonstrate that the HMPC can adjust the vehicle height by controlling the on-off statuses of solenoid valves directly. This research proposes a new modeling and control method for vehicle height adjustment of ECAS, which leads to a closed-loop system with favorable dynamical properties.

  16. Controlled-Temperature Hot-Air Gun

    NASA Technical Reports Server (NTRS)

    Munoz, M. C.

    1986-01-01

    Materials that find applications in wind tunnels first tested in laboratory. Hot-Air Gun differs from commercial units in that flow rate and temperature monitored and controlled. With typical compressed-airsupply pressure of 25 to 38 psi (170 to 260 kPa), flow rate and maximum temperature are 34 stdft3/min (0.96 stdm3/min) and 1,090 degrees F (590 degrees C), respectively. Resembling elaborate but carefully regulated hot-air gun, setup used to apply blasts of air temperatures above 1,500 degrees F (815 degrees C) to test specimens.

  17. Air-fuel ratio control system for an internal combustion engine with a three way catalytic converter

    SciTech Connect

    Fujimura, A.; Sato, Y.

    1986-04-29

    An air-fuel ratio control system is described for an internal combustion engine having at least one of a main fuel passage and a slow fuel passage in a fuel supply system thereof, the air-fuel ratio control system being adapted for performing a feedback control of air-fuel ratio according to a detected oxygen concentration of an exhaust gas of the engine, and comprising: an auxiliary fuel supply means for supplying an auxiliary fuel to the engine through a fuel nozzle opening at a venturi part of a carburetor of the engine; an intake air temperature sensing means for sensing temperature of intake air introduced to the engine; and a control means for operating/stopping the feedback control of air-fuel ratio in accordance with the temperature of intake air sensed by the intake air temperature sensing means, the control means comprising a single control valve being adapted to stop the feedback control of air-fuel ratio and activate the auxiliary fuel supply means and to stop a supply of air into at least one of the main fuel passage and slow fuel passage, for enriching the air-fuel ratio when the temperature of intake air is below a predetermined level.

  18. Safety valve

    DOEpatents

    Bergman, Ulf C.

    1984-01-01

    The safety valve contains a resilient gland to be held between a valve seat and a valve member and is secured to the valve member by a sleeve surrounding the end of the valve member adjacent to the valve seat. The sleeve is movable relative to the valve member through a limited axial distance and a gap exists between said valve member and said sleeve.

  19. Controlled air incinerator conceptual design study

    SciTech Connect

    Not Available

    1982-01-01

    This report presents a conceptual design study for a controlled air incinerator facility for incineration of low level combustible waste at Three Mile Island Unit 2 (TMI-2). The facility design is based on the use of a Helix Process Systems controlled air incinerator. Cost estimates and associated engineering, procurement, and construction schedules are also provided. The cost estimates and schedules are presented for two incinerator facility designs, one with provisions for waste ash solidification, the other with provisions for packaging the waste ash for transport to an undefined location.

  20. Breakdowns in Coordination Between Air Traffic Controllers

    NASA Technical Reports Server (NTRS)

    Bearman, Chris; Orasanu, Judith; Miller, Ronald C.

    2011-01-01

    This talk outlines the complexity of coordination in air traffic control, introduces the NextGen technologies, identifies common causes for coordination breakdowns in air traffic control and examines whether these causes are likely to be reduced with the introduction of NextGen technologies. While some of the common causes of breakdowns will be reduced in a NextGen environment this conclusion should be drawn carefully given the current stage of development of the technologies and the observation that new technologies often shift problems rather than reduce them.

  1. Numerical simulation of the actuation system for the ALDF's propulsion control valve. [Aircraft Landing Dynamics Facility

    NASA Technical Reports Server (NTRS)

    Korte, John J.

    1990-01-01

    A numerical simulation of the actuation system for the propulsion control valve (PCV) of the NASA Langley Aircraft Landing Dynamics Facility was developed during the preliminary design of the PCV and used throughout the entire project. The simulation is based on a predictive model of the PCV which is used to evaluate and design the actuation system. The PCV controls a 1.7 million-pound thrust water jet used in propelling a 108,000-pound test carriage. The PCV can open and close in 0.300 second and deliver over 9,000 gallons of water per sec at pressures up to 3150 psi. The numerical simulation results are used to predict transient performance and valve opening characteristics, specify the hydraulic control system, define transient loadings on components, and evaluate failure modes. The mathematical model used for numerically simulating the mechanical fluid power system is described, and numerical results are demonstrated for a typical opening and closing cycle of the PCV. A summary is then given on how the model is used in the design process.

  2. Loop Heat Pipe with Thermal Control Valve as a Variable Thermal Link

    NASA Technical Reports Server (NTRS)

    Hartenstine, John; Anderson, William G.; Walker, Kara; Dussinger, Pete

    2012-01-01

    Future lunar landers and rovers will require variable thermal links that allow for heat rejection during the lunar daytime and passively prevent heat rejection during the lunar night. During the lunar day, the thermal management system must reject the waste heat from the electronics and batteries to maintain them below the maximum acceptable temperature. During the lunar night, the heat rejection system must either be shut down or significant amounts of guard heat must be added to keep the electronics and batteries above the minimum acceptable temperature. Since guard heater power is unfavorable because it adds to system size and complexity, a variable thermal link is preferred to limit heat removal from the electronics and batteries during the long lunar night. Conventional loop heat pipes (LHPs) can provide the required variable thermal conductance, but they still consume electrical power to shut down the heat transfer. This innovation adds a thermal control valve (TCV) and a bypass line to a conventional LHP that proportionally allows vapor to flow back into the compensation chamber of the LHP. The addition of this valve can achieve completely passive thermal control of the LHP, eliminating the need for guard heaters and complex controls.

  3. 42 CFR 84.137 - Inhalation and exhalation valves; check valves; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Inhalation and exhalation valves; check valves... PROTECTIVE DEVICES Supplied-Air Respirators § 84.137 Inhalation and exhalation valves; check valves; minimum requirements. (a) Inhalation and exhalation valves shall be provided where necessary and protected...

  4. 42 CFR 84.137 - Inhalation and exhalation valves; check valves; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Inhalation and exhalation valves; check valves... PROTECTIVE DEVICES Supplied-Air Respirators § 84.137 Inhalation and exhalation valves; check valves; minimum requirements. (a) Inhalation and exhalation valves shall be provided where necessary and protected...

  5. CATS-based Air Traffic Controller Agents

    NASA Technical Reports Server (NTRS)

    Callantine, Todd J.

    2002-01-01

    This report describes intelligent agents that function as air traffic controllers. Each agent controls traffic in a single sector in real time; agents controlling traffic in adjoining sectors can coordinate to manage an arrival flow across a given meter fix. The purpose of this research is threefold. First, it seeks to study the design of agents for controlling complex systems. In particular, it investigates agent planning and reactive control functionality in a dynamic environment in which a variety perceptual and decision making skills play a central role. It examines how heuristic rules can be applied to model planning and decision making skills, rather than attempting to apply optimization methods. Thus, the research attempts to develop intelligent agents that provide an approximation of human air traffic controller behavior that, while not based on an explicit cognitive model, does produce task performance consistent with the way human air traffic controllers operate. Second, this research sought to extend previous research on using the Crew Activity Tracking System (CATS) as the basis for intelligent agents. The agents use a high-level model of air traffic controller activities to structure the control task. To execute an activity in the CATS model, according to the current task context, the agents reference a 'skill library' and 'control rules' that in turn execute the pattern recognition, planning, and decision-making required to perform the activity. Applying the skills enables the agents to modify their representation of the current control situation (i.e., the 'flick' or 'picture'). The updated representation supports the next activity in a cycle of action that, taken as a whole, simulates air traffic controller behavior. A third, practical motivation for this research is to use intelligent agents to support evaluation of new air traffic control (ATC) methods to support new Air Traffic Management (ATM) concepts. Current approaches that use large, human

  6. Modeling and Control Systems Design by Model Predictive Control for Air-path System of Diesel Engine

    NASA Astrophysics Data System (ADS)

    Iwadare, Mitsuhiro; Ueno, Masaki; Hattori, Yasuharu; Adachi, Shuichi

    Research has been conducted on a variety of combustion technologies in order to reduce diesel engine emissions. These technologies should precisely control the state of in-cylinder gas (EGR mass flow, air mass flow, and so on). However, because the controlled object is a multi-input, multi-output (MIMO) system and a coupled system, the use of control systems based on the conventional methods that employ PID controllers represents a challenge. Model predictive control (MPC) is well known as an MIMO algorithm. An intake control system that could be applied to the intake system of a diesel engine was constructed by supplementing MPC with a feedback function using a disturbance observer and compensator for the nonlinear characteristic of the actuators. Performance tests using an actual vehicle verified that, when applied to a two-input (throttle valve and EGR valve), two-output (air mass flow and intake chamber pressure) system, the proposed MPC is able to rapidly control each output independently to the target value.

  7. Vct system having closed loop control employing spool valve actuated by a stepper motor

    SciTech Connect

    Quin, S.B. Jr.; Siemon, E.C.

    1993-06-15

    An internal combustion engine is described comprising: a crankshaft, the crankshaft being rotable about an axis; a cam shaft, the cam shaft being rotatable about a second axis, the second axis being parallel to the axis, the cam shaft being subject to torque reversals during the rotation thereof; a vane, the vane having at least one lobe, the vane being attached to the cam shaft, being rotatable with the cam shaft and being non-oscillatable with respect to the cam shaft; a housing, the housing being rotatable with the cam shaft and being oscillatable with respect to the cam shaft, the housing having at least one recess, the recess receiving the lobe, the lobe being oscillatable within the recess; rotary movement transmitting means for transmitting rotary movement from the crankshaft to the housing; actuating means for varying the position of the housing relative to the cam shaft in reaction to torque reversals in the cam shaft, the actuating means comprising a stepper motor, a lead screw and a proportional spool valve, the position of the spool valve being controlled by the position of the lead screw driven by the stepper motor, the actuating means also delivering hydraulic fluid to the vane; and processing means for controlling the position of the actuating means.

  8. Magnetorheological valve based actuator for improvement of passively controlled turbocharger system

    NASA Astrophysics Data System (ADS)

    Bahiuddin, I.; Mazlan, S. A.; Imaduddin, F.; Ubaidillah, Ichwan, B.

    2016-03-01

    Variable geometry turbochargers have been widely researched to fulfil the current engine stringent regulations. The passively controlled turbocharger (PCT) concept has been proposed to reduce energy consumption by utilizing the emission energy to move the actuator. However, it only covered a small range operating condition. Therefore, a magnetorheological(MR) Valve device, as typical smart material devices to enhance a passive device, is proposed to improve the PCT. Even though the benefits have been considered for the compactness and easiness to connect to an electrical system, the number of publications regarding the MR application within engine system is hard to be found. Therefore, this paper introduces a design of an MR Valve in a turbocharger. The main challenge is to make sure its capability to produce a sufficient total pressure drop. To overcome the challenge, its material properties, shape and pressure drop calculation has been analyzed to fulfil the requirement. Finally, to get a more understanding of actuator performance, the actuator response was simulated by treating the exhaust gas pressure as an input. It shows that the new MR actuator has a potential dynamic to improve the PCT controllability.

  9. HANDBOOK: CONTROL TECHNIQUES FOR HAZARDOUS AIR POLLUTANTS

    EPA Science Inventory

    This manual is a revision of the first (1986) edition of the Handbook: Control Technologies for Hazardous Air Pollutants, which incorporated information from numerous sources into a single, self-contained reference source focusing on the design and cost of VOC and partic...

  10. Air Traffic Control: Economics of Flight

    NASA Technical Reports Server (NTRS)

    Murphy, James R.

    2004-01-01

    Contents include the following: 1. Commercial flight is a partnership. Airlines. Pilots. Air traffic control. 2. Airline schedules and weather problems can cause delays at the airport. Delays are inevitable in de-regulated industry due to simple economics. 3.Delays can be mitigated. Build more runways/technology. Increase airspace supply. 4. Cost/benefit analysis determine justification.

  11. Combustion, Control, and Fuel Effects in a Spark Assisted HCCI Engine Equipped with Variable Valve Timing

    SciTech Connect

    Bunting, Bruce G

    2006-01-01

    Widespread implementation of homogeneous charge compression ignition (HCCI) engines is presently hindered by stability, control, and load range issues. Although the operable HCCI speed/load range is expanding, it is likely that the initial HCCI engines will rely on conventional combustion for part of the operating cycle. In the present study, we have investigated the role of fuel properties and chemistry on the operation of a spark-assisted gasoline HCCI engine. The engine employed is a single cylinder, 500 cc, port fuel injected research engine, operating near lambda = 1.0 and equipped with hydraulic variable valve actuation. HCCI is initiated by early exhaust valve closing to retain exhaust in the cylinder, thereby increasing the cylinder gas temperature. This is also referred to as a 'negative overlap' strategy. A total of 10 custom blended gasolines and three different batches of indolene from two suppliers were run at 5 speed-load combinations and performance was characterized by timing sweeps. Within the quality of the data set, we can say the all fuels provided equivalent combustion and performance characteristics when compared at the same combustion phasing. The fuels did, however, require different degrees of retained exhaust as measured by exhaust valve closing angle to achieve the same combustion phasing. Fuels with higher octane sensitivity were found to ignite more easily or more quickly and to burn more quickly than fuels with lower octane sensitivity. This is an expected result since the engine is naturally aspirated and operates with high compression temperatures due to the high retained exhaust fraction and recompression.

  12. Experimental Investigation of a Reed Valve on the Performance of a Pulse Detonation Engine

    NASA Astrophysics Data System (ADS)

    Ma, Hu; Wu, Xiao-song; Wang, Dong; Cai, Wen-xiang; Chen, Jie; Diao, Ji-yang; Chen-xi, Pei

    2013-12-01

    Valve system is an important part of pulse detonation engine (PDE). The purpose of this research was to demonstrate the feasibility of utilizing a reed valve to inject fuel/air mixture into the combustion chamber of a Pulsed Detonation Engine (PDE). Using air as oxidizer and liquid C8H18 as fuel, a series of multi-cycle detonation experiments were investigated. The experimental results indicated that the reed valve was able to realize supply control of single-tube PDE effectively, and achieved stable operation about 3 minutes at 12.5 Hz for 0.15 mm valve sheet and 30° limit baffle plate. The response time and total pressure recovery coefficient of the reed valve were influenced by valve sheet thickness and air mass flow rate. For 0.1 mm valve sheet and 45° limit baffle plate, the service life of valve sheet strikingly shortened. Some factors such as the valve sheet thickness, air mass flow rate and the limit baffle plate's angle, should be comprehensively considered to design a reed valve.

  13. Air-Powered Projectile Launcher

    NASA Technical Reports Server (NTRS)

    Andrews, T.; Bjorklund, R. A.; Elliott, D. G.; Jones, L. K.

    1987-01-01

    Air-powered launcher fires plastic projectiles without using explosive propellants. Does not generate high temperatures. Launcher developed for combat training for U.S. Army. With reservoir pressurized, air launcher ready to fire. When pilot valve opened, sleeve (main valve) moves to rear. Projectile rapidly propelled through barrel, pushed by air from reservoir. Potential applications in seismic measurements, avalanche control, and testing impact resistance of windshields on vehicles.

  14. Situational Leadership in Air Traffic Control

    NASA Technical Reports Server (NTRS)

    Arvidsson, Marcus; Johansson, Curt R.; Ek, Asa; Akselsson, Roland

    2007-01-01

    In high-risk environments such as air traffic control, leadership on different levels plays a certain role in establishing, promoting, and maintaining a good safety culture. The current study aimed to investigate how leadership styles, leadership style adaptability, and over and under task leadership behavior differed across situations, operative conditions, leadership structures, and working tasks in an air traffic control setting. Study locations were two air traffic control centers in Sweden with different operational conditions and leadership structures, and an administrative air traffic management unit. Leadership was measured with a questionnaire based on Leader Effectiveness and Adaptability Description (LEAD; Blanchard, Zigarmi & Zigarmi, 2003; Hersey & Blanchard, 1988). The results showed that the situation had strong impact on the leadership in which the leadership behavior was more relationship oriented in Success and Group situations than in Hardship and Individual situations. The leadership adaptability was further superior in Success and Individual situations compared with Hardship and Group situations. Operational conditions, leadership structures and working tasks were, on the other hand, not associated with leadership behavior.

  15. Stiffness and Adhesivity Control Aortic Valve Interstitial Cell Behavior within Hyaluronic Acid Based Hydrogels

    PubMed Central

    Duan, Bin; Hockaday, Laura A.; Kapetanovic, Edi; Kang, Kevin H.; Butcher, Jonathan T.

    2013-01-01

    Bioactive and biodegradable hydrogels that mimic the extracellular matrix and regulate valve interstitial cells (VIC) behavior are of great interest as three dimensional (3D) model systems for understanding mechanisms of valvular heart disease pathogenesis in vitro and the basis for regenerative templates for tissue engineering. However, the role of stiffness and adhesivity of hydrogels in VIC behavior remains poorly understood. This study reports synthesis of oxidized and methacrylated hyaluronic acid (Me-HA and MOHA) and subsequent development of hybrid hydrogels based on modified HA and methacrylated gelatin (Me-Gel) for VIC encapsulation. The mechanical stiffness and swelling ratio of the hydrogels were tunable with molecular weight of HA and concentration/composition of precursor solution. The encapsulated VIC in pure HA hydrogels with lower mechanical stiffness showed more spreading morphology comparing to stiffer counterparts and dramatically upregulated alpha smooth muscle actin expression indicating more activated myofibroblast properties. The addition of Me-Gel in Me-HA facilitated cell spreading, proliferation and VIC migration from encapsulated spheroids and better maintained VIC fibroblastic phenotype. The VIC phenotype transition during migration from encapsulated spheroids in both Me-HA and Me-HA/Me-Gel hydrogel matrix was also observed. These findings are important for the rational design of hydrogels for controlling VIC morphology, and for regulating VIC phenotype and function. The Me-HA/Me-Gel hybrid hydrogels accommodated with VIC are promising as valve tissue engineering scaffolds and 3D model for understanding valvular pathobiology. PMID:23648571

  16. Mesofluidic two stage digital valve

    DOEpatents

    Jansen, John F; Love, Lonnie J; Lind, Randall F; Richardson, Bradley S

    2013-12-31

    A mesofluidic scale digital valve system includes a first mesofluidic scale valve having a valve body including a bore, wherein the valve body is configured to cooperate with a solenoid disposed substantially adjacent to the valve body to translate a poppet carried within the bore. The mesofluidic scale digital valve system also includes a second mesofluidic scale valve disposed substantially perpendicular to the first mesofluidic scale valve. The mesofluidic scale digital valve system further includes a control element in communication with the solenoid, wherein the control element is configured to maintain the solenoid in an energized state for a fixed period of time to provide a desired flow rate through an orifice of the second mesofluidic valve.

  17. 30 CFR 780.15 - Air pollution control plan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Air pollution control plan. 780.15 Section 780....15 Air pollution control plan. (a) For all surface mining activities with projected production rates... application shall contain an air pollution control plan which includes the following: (1) An air...

  18. 30 CFR 780.15 - Air pollution control plan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Air pollution control plan. 780.15 Section 780....15 Air pollution control plan. (a) For all surface mining activities with projected production rates... application shall contain an air pollution control plan which includes the following: (1) An air...

  19. 30 CFR 780.15 - Air pollution control plan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Air pollution control plan. 780.15 Section 780....15 Air pollution control plan. (a) For all surface mining activities with projected production rates... application shall contain an air pollution control plan which includes the following: (1) An air...

  20. 30 CFR 780.15 - Air pollution control plan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Air pollution control plan. 780.15 Section 780....15 Air pollution control plan. (a) For all surface mining activities with projected production rates... application shall contain an air pollution control plan which includes the following: (1) An air...

  1. 30 CFR 780.15 - Air pollution control plan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Air pollution control plan. 780.15 Section 780....15 Air pollution control plan. (a) For all surface mining activities with projected production rates... application shall contain an air pollution control plan which includes the following: (1) An air...

  2. Modeling study of the ABS relay valve

    NASA Astrophysics Data System (ADS)

    Lei, Ming; Lin, Min; Guo, Bin; Luo, Zai; Xu, Weidong

    2011-05-01

    The ABS (anti-lock braking system) relay valve is the key component of anti-lock braking system in most commercial vehicles such as trucks, tractor-trailers, etc. In this paper, structure of ABS relay valve and its work theory were analyzed. Then a mathematical model of ABS relay valve, which was investigated by dividing into electronic part, magnetic part, pneumatic part and mechanical part, was set up. The displacement of spools and the response of pressure increasing, holding, releasing of ABS relay valve were simulated and analyzed under conditions of control pressure 500 KPa, braking pressure 600 KPa, atmospheric pressure 100 KPa and air temperature 310 K. Thisarticle provides reliable theory for improving the performance and efficiency of anti-lock braking system of vehicles.

  3. Modeling study of the ABS relay valve

    NASA Astrophysics Data System (ADS)

    Lei, Ming; Lin, Min; Guo, Bin; Luo, Zai; Xu, Weidong

    2010-12-01

    The ABS (anti-lock braking system) relay valve is the key component of anti-lock braking system in most commercial vehicles such as trucks, tractor-trailers, etc. In this paper, structure of ABS relay valve and its work theory were analyzed. Then a mathematical model of ABS relay valve, which was investigated by dividing into electronic part, magnetic part, pneumatic part and mechanical part, was set up. The displacement of spools and the response of pressure increasing, holding, releasing of ABS relay valve were simulated and analyzed under conditions of control pressure 500 KPa, braking pressure 600 KPa, atmospheric pressure 100 KPa and air temperature 310 K. Thisarticle provides reliable theory for improving the performance and efficiency of anti-lock braking system of vehicles.

  4. Combined air and water pollution control system

    NASA Technical Reports Server (NTRS)

    Wolverton, Billy C. (Inventor); Jarrell, Lamont (Inventor)

    1990-01-01

    A bioaquatic air pollution control system for controlling both water and atmospheric pollution is disclosed. The pollution control system includes an exhaust for directing polluted gases out of a furnace and a fluid circulating system which circulates fluid, such as waste water, from a source, past the furnace where the fluid flow entrains the pollutants from the furnace. The combined fluid and pollutants are then directed through a rock/plant/microbial filtering system. A suction pump pumps the treated waste water from the filter system past the exhaust to again entrain more pollutants from the furnace where they are combined with the fluid (waste water) and directed to the filter system.

  5. Building pressurization control with rooftop air conditioners

    SciTech Connect

    Winter, S.

    1982-10-01

    The modulated exhaust fan appears to be the most cost effective positive means to maintain close building pressure control with rooftop air conditioning, but because building construction and applications vary, every building's pressure control needs must be analyzed. Requirements will vary from no relief to barometric dampers to return fans to modulated exhaust fans. As heating and cooling costs continue to rise and tighter building codes prevail, proper selection of building pressure control is one area that must be monitored more carefully by the HVAC system designer.

  6. Automated Conflict Resolution For Air Traffic Control

    NASA Technical Reports Server (NTRS)

    Erzberger, Heinz

    2005-01-01

    The ability to detect and resolve conflicts automatically is considered to be an essential requirement for the next generation air traffic control system. While systems for automated conflict detection have been used operationally by controllers for more than 20 years, automated resolution systems have so far not reached the level of maturity required for operational deployment. Analytical models and algorithms for automated resolution have been traffic conditions to demonstrate that they can handle the complete spectrum of conflict situations encountered in actual operations. The resolution algorithm described in this paper was formulated to meet the performance requirements of the Automated Airspace Concept (AAC). The AAC, which was described in a recent paper [1], is a candidate for the next generation air traffic control system. The AAC's performance objectives are to increase safety and airspace capacity and to accommodate user preferences in flight operations to the greatest extent possible. In the AAC, resolution trajectories are generated by an automation system on the ground and sent to the aircraft autonomously via data link .The algorithm generating the trajectories must take into account the performance characteristics of the aircraft, the route structure of the airway system, and be capable of resolving all types of conflicts for properly equipped aircraft without requiring supervision and approval by a controller. Furthermore, the resolution trajectories should be compatible with the clearances, vectors and flight plan amendments that controllers customarily issue to pilots in resolving conflicts. The algorithm described herein, although formulated specifically to meet the needs of the AAC, provides a generic engine for resolving conflicts. Thus, it can be incorporated into any operational concept that requires a method for automated resolution, including concepts for autonomous air to air resolution.

  7. A hierarchical framework for air traffic control

    NASA Astrophysics Data System (ADS)

    Roy, Kaushik

    Air travel in recent years has been plagued by record delays, with over $8 billion in direct operating costs being attributed to 100 million flight delay minutes in 2007. Major contributing factors to delay include weather, congestion, and aging infrastructure; the Next Generation Air Transportation System (NextGen) aims to alleviate these delays through an upgrade of the air traffic control system. Changes to large-scale networked systems such as air traffic control are complicated by the need for coordinated solutions over disparate temporal and spatial scales. Individual air traffic controllers must ensure aircraft maintain safe separation locally with a time horizon of seconds to minutes, whereas regional plans are formulated to efficiently route flows of aircraft around weather and congestion on the order of every hour. More efficient control algorithms that provide a coordinated solution are required to safely handle a larger number of aircraft in a fixed amount of airspace. Improved estimation algorithms are also needed to provide accurate aircraft state information and situational awareness for human controllers. A hierarchical framework is developed to simultaneously solve the sometimes conflicting goals of regional efficiency and local safety. Careful attention is given in defining the interactions between the layers of this hierarchy. In this way, solutions to individual air traffic problems can be targeted and implemented as needed. First, the regional traffic flow management problem is posed as an optimization problem and shown to be NP-Hard. Approximation methods based on aggregate flow models are developed to enable real-time implementation of algorithms that reduce the impact of congestion and adverse weather. Second, the local trajectory design problem is solved using a novel slot-based sector model. This model is used to analyze sector capacity under varying traffic patterns, providing a more comprehensive understanding of how increased automation

  8. Internal combustion engine and method for control

    SciTech Connect

    Brennan, Daniel G

    2013-05-21

    In one exemplary embodiment of the invention an internal combustion engine includes a piston disposed in a cylinder, a valve configured to control flow of air into the cylinder and an actuator coupled to the valve to control a position of the valve. The internal combustion engine also includes a controller coupled to the actuator, wherein the controller is configured to close the valve when an uncontrolled condition for the internal engine is determined.

  9. CAM operated fuel valve

    SciTech Connect

    Kelly, S.T.; Katchka, J.R.

    1991-09-03

    This patent describes improvement in a fuel control valve construction comprising a housing means having an inlet means adapted to be interconnected to a fuel source and a main outlet means adapted to be interconnected to a main burner means, the housing means having a main valve seat for interconnecting the inlet means with the main outlet means, the housing means having a movable main valve member for opening and closing the main valve seat, the housing means having a movable lever operatively associated with the main valve member and having a manually operable actuator means for controlling the operating positions of the lever, the lever having an intermediate cam follower portion and opposed ends disposed on each side of the cam follower portion with one end of the opposed ends being pivotally mounted to the housing means and with the other end of the opposed ends for operating the main valve member, the housing means having biasing means operatively interconnected to the lever to tend to pivot the lever in one direction that opens the main valve member away from its the main valve seat. The improvement comprises; the housing means has a thermostatically controlled means that is operatively associated with the lever and is adapted to engage and hold the lever in a position wherein the main valve member is in a closed condition against its the main valve seat when the thermostatically controlled means is in one operating condition thereof and the actuator means is in the on condition thereof.

  10. Air Traffic Control Improvement Using Prioritized CSMA

    NASA Technical Reports Server (NTRS)

    Robinson, Daryl C.

    2001-01-01

    Version 7 simulations of the industry-standard network simulation software "OPNET" are presented of two applications of the Aeronautical Telecommunications Network (ATN), Controller Pilot Data Link Communications (CPDLC) and Automatic Dependent Surveillance-Broadcast mode (ADS-B), over VHF Data Link mode 2 (VDL-2). Communication is modeled for air traffic between just three cities. All aircraft are assumed to have the same equipage. The simulation involves Air Traffic Control (ATC) ground stations and 105 aircraft taking off, flying realistic free-flight trajectories, and landing in a 24-hr period. All communication is modeled as unreliable. Collision-less, prioritized carrier sense multiple access (CSMA) is successfully tested. The statistics presented include latency, queue length, and packet loss. This research may show that a communications system simpler than the currently accepted standard envisioned may not only suffice, but also surpass performance of the standard at a lower cost of deployment.

  11. Main Oxidizer Valve Design

    NASA Technical Reports Server (NTRS)

    Addona, Brad; Eddleman, David

    2015-01-01

    A developmental Main Oxidizer Valve (MOV) was designed by NASA-MSFC using additive manufacturing processes. The MOV is a pneumatically actuated poppet valve to control the flow of liquid oxygen to an engine's injector. A compression spring is used to return the valve to the closed state when pneumatic pressure is removed from the valve. The valve internal parts are cylindrical in shape, which lends itself to traditional lathe and milling operations. However, the valve body represents a complicated shape and contains the majority of the mass of the valve. Additive manufacturing techniques were used to produce a part that optimized mass and allowed for design features not practical with traditional machining processes.

  12. Shutoff and throttling valve

    NASA Technical Reports Server (NTRS)

    Hays, L. G.

    1974-01-01

    Leaktight shutoff, precise flow control, and very low pressure drop are incorporated in all-metal valve designed for operation under extreme temperatures. Valve constructed with refractory metal is intended for control of high-temperature liquid cesium, but has applications related to control of high- and low-temperature liquids and gases.

  13. Fuel control valve construction, parts therefor and methods of making the same

    SciTech Connect

    Kelly, S.T.; Katchka, J.R.

    1988-11-29

    This patent describes the combination comprising a supporting means, electrically operated coil means carried by the supporting means, two movable plunger means carried by the supporting means in generally a side-by-side spaced apart parallel relation and being operatively associated with the coil means to be moved to certain positions thereof when the coil means is energized, and two separate valve means carried by the supporting means and respectively being operatively associated with the plunger means to be controlled thereby, the improvement wherein the coil means comprises a single coil having a portion of one of the plunger means disposed therein, the other of the plunger means being entirely external to the coil while being adapted to be operated by the coil substantially in unison with the one plunger means.

  14. Failure Analysis of Fractured Poppet from Space Shuttle Orbiter Flow Control Valve

    NASA Technical Reports Server (NTRS)

    Russell, Richard

    2010-01-01

    This slide presentation reviews the failure analysis of a fractured poppet from a flow control valve (FCV) used on the space shuttle. This presentation has focused on the laboratory analysis of the failed hardware. The use of Scanning electron fractography during the investigation led to the conclusion that the poppet failed due to fatigue cracking that, most likely, occurred under changing loading conditions. The initial investigation led to a more thorough test of poppets that had been retired, this testing led to the conclusion that the thumbnail cracks in the flight hardware had existed for the life of the shuttle program. This led to a program to develop an eddy current technique that was capable of detecting small very tight cracks.

  15. Polypropylene vs silicone Ahmed valve with adjunctive mitomycin C in paediatric age group: a prospective controlled study

    PubMed Central

    El Sayed, Y; Awadein, A

    2013-01-01

    Purpose To compare the results of silicone and polypropylene Ahmed glaucoma valves (AGV) implanted during the first 10 years of life. Methods A prospective study was performed on 50 eyes of 33 patients with paediatric glaucoma. Eyes were matched to either polypropylene or silicone AGV. In eyes with bilateral glaucoma, one eye was implanted with polypropylene and the other eye was implanted with silicone AGV. Results Fifty eyes of 33 children were reviewed. Twenty five eyes received a polypropylene valve, and 25 eyes received a silicone valve. Eyes implanted with silicone valves achieved a significantly lower intraocular pressure (IOP) compared with the polypropylene group at 6 months, 1 year, and 2 years postoperatively. The average survival time was significantly longer (P=0.001 by the log-rank test) for the silicone group than for the polypropylene group and the cumulative probability of survival by the log-rank test at the end of the second year was 80% (SE: 8.0, 95% confidence interval (CI): 64–96%) in the silicone group and 56% (SE: 9.8, 95% CI: 40–90%) in the polypropylene group. The difference in the number of postoperative interventions and complications between both groups was statistically insignificant. Conclusion Silicone AGVs can achieve better IOP control, and longer survival with less antiglaucoma drops compared with polypropylene valves in children younger than 10 years. PMID:23579403

  16. Controlled generation of double emulsions in air.

    PubMed

    Liu, Dingsheng; Hakimi, Bejan; Volny, Michael; Rolfs, Joelle; Chen, Xudong; Turecek, Frantisek; Chiu, Daniel T

    2013-07-01

    This Letter describes the controlled generation of double emulsions in the gas phase, which was carried out using an integrated emitter in a poly(dimethylsiloxane) (PDMS) microfluidic chip. The integrated emitter was formed using a molding approach, in which metal wires with desirable diameters were used as emitter molds. The generation of double emulsions in air was achieved with electrohydrodynamics actuation, which offers controllable force exerting on the double emulsions. We developed this capability for future integration of droplet microfluidics with mass spectrometry (MS), where each aqueous droplet in the microchannel is introduced into the gas phase as a double emulsion for subsequent ionization and MS analysis. PMID:23767768

  17. Pressure model of a four-way spool valve for simulating electrohydraulic control systems

    NASA Technical Reports Server (NTRS)

    Gebben, V. D.

    1976-01-01

    An equation that relates the pressure flow characteristics of hydraulic spool valves was developed. The dependent variable is valve output pressure, and the independent variables are spool position and flow. This causal form of equation is preferred in applications that simulate the effects of hydraulic line dynamics. Results from this equation are compared with those from the conventional valve equation, whose dependent variable is flow. A computer program of the valve equations includes spool stops, leakage spool clearances, and dead-zone characteristics of overlap spools.

  18. Preliminary design for hot dirty-gas control-valve test facility. Final report

    SciTech Connect

    Not Available

    1980-01-01

    This report presents the results of a preliminary design and cost estimating effort for a facility for the testing of control valves in Hot Dirty Gas (HDGCV) service. This design was performed by Mittelhauser Corporation for the United States Department of Energy's Morgantown Energy Technology Center (METC). The objective of this effort was to provide METC with a feasible preliminary design for a test facility which could be used to evaluate valve designs under simulated service conditions and provide a technology data base for DOE and industry. In addition to the actual preliminary design of the test facility, final design/construction/operating schedules and a facility cost estimate were prepared to provide METC sufficient information with which to evaluate this design. The bases, assumptions, and limitations of this study effort are given. The tasks carried out were as follows: METC Facility Review, Environmental Control Study, Gas Generation Study, Metallurgy Review, Safety Review, Facility Process Design, Facility Conceptual Layout, Instrumentation Design, Cost Estimates, and Schedules. The report provides information regarding the methods of approach used in the various tasks involved in the completion of this study. Section 5.0 of this report presents the results of the study effort. The results obtained from the above-defined tasks are described briefly. The turnkey cost of the test facility is estimated to be $9,774,700 in fourth quarter 1979 dollars, and the annual operating cost is estimated to be $960,000 plus utilities costs which are not included because unit costs per utility were not available from METC.

  19. 75 FR 18061 - Approval and Promulgation of Air Quality Implementation Plans; Texas; Control of Air Pollution...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-09

    ... Air Pollution From Motor Vehicles AGENCY: Environmental Protection Agency (EPA). ACTION: Direct final... amend 30 TAC Chapter 114, Control of Air Pollution from Motor Vehicles. These revisions consist of the... to develop air pollution regulations and control strategies to ensure that air quality meets...

  20. A risk assessment and control model for the failing Björk-Shiley convexo-concave heart valve.

    PubMed

    Koornneef, F; van Gaalen, G L; de Mol, B A

    1996-01-01

    For risk assessment and control of the failing Björk-Shiley convexo-concave heart valve, we present a life cycle-based complex system model and a risk intensity assessment model, allowing consistent analysis of this complex medical problem and identification of all pertinent aspects of product-related risks to patients.

  1. 14 CFR 23.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Carburetor air temperature controls. 23... Powerplant Powerplant Controls and Accessories § 23.1157 Carburetor air temperature controls. There must be a separate carburetor air temperature control for each engine....

  2. 14 CFR 23.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Carburetor air temperature controls. 23... Powerplant Powerplant Controls and Accessories § 23.1157 Carburetor air temperature controls. There must be a separate carburetor air temperature control for each engine....

  3. 14 CFR 23.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Carburetor air temperature controls. 23... Powerplant Powerplant Controls and Accessories § 23.1157 Carburetor air temperature controls. There must be a separate carburetor air temperature control for each engine....

  4. 14 CFR 23.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Carburetor air temperature controls. 23... Powerplant Powerplant Controls and Accessories § 23.1157 Carburetor air temperature controls. There must be a separate carburetor air temperature control for each engine....

  5. 14 CFR 23.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Carburetor air temperature controls. 23... Powerplant Powerplant Controls and Accessories § 23.1157 Carburetor air temperature controls. There must be a separate carburetor air temperature control for each engine....

  6. VAPOR VALVE

    DOEpatents

    Wouters, L.F.

    1959-08-25

    Electromagnetically operated vapor valves are described for apparatus employed in the separation of isotopes or elements to control the flow of gaseous vapors between a vaporizing charge chamber and an ionizing chamber, The charge chamber and ionizing chamber are positioned in a magnetic field, and the flow of vapors through an orifice connecting the chambers is regulated by regulating the flow of current through a resilient metal strip rigidly mounted at one end and positioned in the magnetic field adjacent to the orifice.

  7. Ground Simulator Studies of the Effects of Valve Friction, Stick Friction, Flexibility, and Backwash on Power Control System Quality

    NASA Technical Reports Server (NTRS)

    Brown, B Porter

    1958-01-01

    Report presents results of tests made on a power control system by means of a ground simulator to determine the effects of various combinations of valve friction and stick friction on the ability of the pilot to control the system. Various friction conditions were simulated with a rigid control system, a flexible system, and a rigid system having some backlash. For the tests, the period and damping of the simulated airplane were held constant.

  8. Lessons Learned from the Space Shuttle Engine Hydrogen Flow Control Valve Poppet Breakage

    NASA Technical Reports Server (NTRS)

    Martinez, Hugo E.; Damico, Stephen; Brewer, John

    2011-01-01

    The Main Propulsion System (MPS) uses three Flow Control Valves (FCV) to modulate the flow of pressurant hydrogen gas from the Space Shuttle Main Engines (SSME) to the hydrogen External Tank (ET). This maintains pressure in the ullage volume as the liquid level drops, preserving ET structural integrity and assuring the engines receive a sufficient amount of head pressure. On Space Transportation System (STS)-126 (2009), with only a handful of International Space Station (ISS) assembly flights from the end of the Shuttle program, a portion of a single FCV?s poppet head broke off at about a minute and a half after liftoff. The risk of the poppet head failure is that the increased flow area through the FCV could result in excessive gaseous hydrogen flow back to the external tank, which could result in overboard venting of hydrogen ullage pressure. If the hydrogen venting were to occur in first stage (i.e., lower atmosphere), a flammability hazard exists that could lead to catastrophic loss of crew and vehicle. Other failure risks included particle impact damage to MPS downstream hardware. Although the FCV design had been plagued by contamination-related sluggish valve response problems prior to a redesign at STS-80 (1996), contamination was ruled out as the cause of the STS-126 failure. Employing a combination of enhanced hardware inspection and a better understanding of the consequences of a poppet failure, safe flight rationale for subsequent flights (STS-119 and later) was achieved. This paper deals with the technical lessons learned during the investigation and mitigation of this problem at a time when assembly flights were each in the critical path to Space Station success.

  9. A Novel Implantable Glaucoma Valve Using Ferrofluid

    PubMed Central

    Paschalis, Eleftherios I.; Chodosh, James; Sperling, Ralph A.; Salvador-Culla, Borja; Dohlman, Claes

    2013-01-01

    Purpose To present a novel design of an implantable glaucoma valve based on ferrofluidic nanoparticles and to compare it with a well-established FDA approved valve. Setting Massachusetts Eye & Ear Infirmary, Boston, USA. Methods A glaucoma valve was designed using soft lithography techniques utilizing a water-immiscible magnetic fluid (ferrofluid) as a pressure-sensitive barrier to aqueous flow. Two rare earth micro magnets were used to calibrate the opening and closing pressure. In-vitro flow measurements were performed to characterize the valve and to compare it to Ahmed™ glaucoma valve. The reliability and predictability of the new valve was verified by pressure/flow measurements over a period of three months and X-ray diffraction (XRD) analysis over a period of eight weeks. In vivo assessment was performed in three rabbits. Results In the in vitro experiments, the opening and closing pressures of the valve were 10 and 7 mmHg, respectively. The measured flow/pressure response was linearly proportional and reproducible over a period of three months (1.8 µl/min at 12 mmHg; 4.3 µl/min at 16 mmHg; 7.6 µl/min at 21 mmHg). X-ray diffraction analysis did not show oxidization of the ferrofluid when exposed to water or air. Preliminary in vivo results suggest that the valve is biocompatible and can control the intraocular pressure in rabbits. Conclusions The proposed valve utilizes ferrofluid as passive, tunable constriction element to provide highly predictable opening and closing pressures while maintaining ocular tone. The ferrofluid maintained its magnetic properties in the aqueous environment and provided linear flow to pressure response. Our in-vitro tests showed reliable and reproducible results over a study period of three months. Preliminary in-vivo results were very promising and currently more thorough investigation of this device is underway. PMID:23840691

  10. Controls on ostracod valve geochemistry, Part 1: Variations of environmental parameters in ostracod (micro-)habitats

    NASA Astrophysics Data System (ADS)

    Decrouy, Laurent; Vennemann, Torsten Walter; Ariztegui, Daniel

    2011-11-01

    The variations of environmental conditions ( T°, pH, δ 13C DIC, [DIC], δ 18O, Mg/Ca, and Sr/Ca) of ostracod habitats were examined to determine the controls of environmental parameters on the chemical and isotopic composition of ostracod valves. Results of a one-year monitoring of environmental parameters at five sites, with depths of between 2 and 70 m, in Lake Geneva indicate that in littoral to sub-littoral zones (2, 5, and 13 m), the chemical composition of bottom water varies seasonally in concert with changes in temperature and photosynthetic activity. An increase of temperature and photosynthetic activity leads to an increase in δ 13C values of DIC and to precipitation of authigenic calcite, which results in a concomitant increase of Mg/Ca and Sr/Ca ratios of water. In deeper sites (33 and 70 m), the composition of bottom water remains constant throughout the year and isotopic values and trace element contents are similar to those of deep water within the lake. The chemical composition of interstitial pore water also does not reflect seasonal variations but is controlled by calcite dissolution, aerobic respiration, anaerobic respiration with reduction of sulphate and/or nitrate, and methanogenesis that may occur in the sediment pores. Relative influence of each of these factors on the pore water geochemistry depends on sediment thickness and texture, oxygen content in bottom as well as pore water. Variations of chemical compositions of the ostracod valves of this study vary according to the specific ecology of the ostracod species analysed, that is its life-cycle and its (micro-)habitat. Littoral species have compositions that are related to the seasonal variations of temperature, δ 13C values of DIC, and of Mg/Ca and Sr/Ca ratios of water. In contrast, the compositions of profundal species are largely controlled by variations of pore fluids along sediment depth profiles according to the specific depth preference of the species. The control on the

  11. Prediction Models are Basis for Rational Air Quality Control

    ERIC Educational Resources Information Center

    Daniels, Anders; Bach, Wilfrid

    1973-01-01

    An air quality control scheme employing meteorological diffusion, time averaging and frequency, and cost-benefit models is discussed. The methods outlined provide a constant feedback system for air quality control. Flow charts and maps are included. (BL)

  12. Passive ventilation for residential air quality control

    SciTech Connect

    Axley, J.

    1999-07-01

    Infiltration has long served the residential ventilation needs in North America. In Northern Europe it has been augmented by purpose-provided natural ventilation systems--so-called passive ventilation systems--to better control moisture problems in dwellings smaller than their North American counterparts and in a generally wetter climate. The growing concern for energy consumption, and the environmental impacts associated with it, has however led to tighter residential construction standards on both continents and as a result problems associated with insufficient background ventilation have surfaced. Can European passive ventilation systems be adapted for use in North American dwellings to provide general background ventilation for air quality control? This paper attempts to answer this question. The configuration, specifications and performance of the preferred European passive ventilation system--the passive stack ventilation (PSV) system--will be reviewed; innovative components and system design strategies recently developed to improve the traditional PSV system performance will be outlined; and alternative system configurations will be presented that may better serve the climatic extremes and more urban contexts of North America. While these innovative and alternative passive ventilation systems hold great promise for the future, a rational method to size the components of these systems to achieve the control and precision needed to meet the conflicting constraints of new ventilation and air tightness standards has not been forthcoming. Such a method will be introduced in this paper and an application of this method will be presented.

  13. ELECTROSTRICTION VALVE

    DOEpatents

    Kippenhan, D.O.

    1962-09-25

    An accurately controlled, pulse gas valve is designed capable of delivering output pulses which vary in length from one-tenth millisecond to one second or more, repeated at intervals of a few milliseconds or- more. The pulsed gas valve comprises a column formed of barium titanate discs mounted in stacked relation and electrically connected in parallel, with means for applying voltage across the discs to cause them to expand and effect a mechanical elongation axially of the column. The column is mounted within an enclosure having an inlet port and an outlet port with an internal seat in communication with the outlet port, such that a plug secured to the end of the column will engage the seat of the outlet port to close the outlet port in response to the application of voltage is regulated by a conventional electronic timing circuit connected to the column. (AEC)

  14. Automatic venting valve for gas storage tank

    SciTech Connect

    Johnson, H.

    1986-12-02

    A control valve is described for blocking atmospheric venting of gas fumes contained within a gasoline storage tank during tanker refill operations. The gasoline tank includes a venting tube coupled to open space within the top of the tank to provide air intake for pressure equalization as gasoline is gradually removed from the tank, the control valve comprising: a. a rigid, tubular valve casing having a top opening, a bottom opening and a flow channel therebetween; b. means for attaching the bottom end of the casing to an upper end of the venting tube such that the valve flow channel forms a continuation venting path for the venting tube; c. first and second valve seats and an intermediate seating member coupled to the casing and at least partially contained within the flow channel. The seating member is configured in shape and size to form restricted air space between the seating member and a surrounding wall of the flow channel to be reversibly displaceable in response to fume exhaust expelled during refill operations.

  15. The Electronic Valve Instrument (EVI), an electronic musical wind controller for playing synthesizers

    NASA Astrophysics Data System (ADS)

    Steiner, Nyle A.

    2001-05-01

    The Electronic Valve Instrument (EVI) is an electronic musical wind instrument with playing techniques similar to that of a trumpet. Invented by Nyle Steiner in the early 1970's, it was designed to give the performer control of dynamics from breath pressure and the ability to make a humanly generated vibrato. Other musical paramaters can be controlled as well. It has a playing range of seven octaves (similar to that of a piano). When musical lines are played using this instrument (controller) connected to an electronic music synthesizer, the sound is much more natural sounding and expressive than when a normal musical keyboard is used. The evolution of this instrument from the pre-Midi era to it latest Midi configuration, principles of operation, synthesizer programming, and its wide use in movie and TV scoring will be discussed. The EVI has played featured musical lines in many major movie soundtracks and TV shows such as Apocalypse Now, Witness, Dead Poets Society, Fatal Attraction, No Way Out, Gorillas in the Mist, and many others. The EVI design has also been adapted as an Electronic Woodwind Instrument (EWI) by Nyle Steiner and has been manufactured and sold worldwide by the AKAI Co. in Japan.

  16. 30 CFR 784.26 - Air pollution control plan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Air pollution control plan. 784.26 Section 784... § 784.26 Air pollution control plan. For all surface operations associated with underground mining activities, the application shall contain an air pollution control plan which includes the following: (a)...

  17. 30 CFR 784.26 - Air pollution control plan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Air pollution control plan. 784.26 Section 784... § 784.26 Air pollution control plan. For all surface operations associated with underground mining activities, the application shall contain an air pollution control plan which includes the following: (a)...

  18. 30 CFR 784.26 - Air pollution control plan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Air pollution control plan. 784.26 Section 784... § 784.26 Air pollution control plan. For all surface operations associated with underground mining activities, the application shall contain an air pollution control plan which includes the following: (a)...

  19. 30 CFR 784.26 - Air pollution control plan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Air pollution control plan. 784.26 Section 784... § 784.26 Air pollution control plan. For all surface operations associated with underground mining activities, the application shall contain an air pollution control plan which includes the following: (a)...

  20. 30 CFR 784.26 - Air pollution control plan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Air pollution control plan. 784.26 Section 784... § 784.26 Air pollution control plan. For all surface operations associated with underground mining activities, the application shall contain an air pollution control plan which includes the following: (a)...

  1. Electrolytic Valving Isolation for Cell Co-Culture Microenvironment with Controlled Cell Pairing Ratios

    PubMed Central

    Chen, Yu-Chih; Ingram, Patrick; Yoon, Euisik

    2016-01-01

    Cancer-stromal interaction is a critical process in tumorigenesis. Conventional dish-based co-culture assays simply mix two cell types in the same dish; thus, they are deficient in controlling cell locations and precisely tracking single cell behavior from heterogeneous cell populations. Microfluidic technology can provide a good spatial temporal control of microenvironments, but the control has been typically realized by using external pumps, making long-term cultures cumbersome and bulky. In this work, we present a cell-cell interaction microfluidic platform that can accurately control co-culture microenvironment by using a novel electrolytic cell isolation scheme without using any valves or pneumatic pumps. The proposed microfluidic platform can also precisely control the number of interacting cells and pairing ratios to emulate cancer niches. More than 80% of the chambers captured the desired number of cells. The duration of cell isolation can be adjusted by electrolytic bubble generation and removal. We verified that electrolytic process has a negligible effect on cell viability and proliferation in our platform. To the best of our knowledge, this work is the first attempt to incorporate electrolytic bubble generation as a cell isolation method in microfluidics. For proof of feasibility, we performed cell-cell interaction assays between prostate cancer (PC3) cells and myoblast (C2C12) cells. The preliminary results demonstrated the potential of using electrolysis for micro-environmental control during cell culture. Also, the ratio controlled cell-cell interaction assays was successfully performed showing that the cell pairing ratios of PC3 to C2C12 affected the proliferation rate of myoblast cells due to increased secretion of growth factors from prostate cancer cells. PMID:25118341

  2. Air quality and pollution control in Taiwan

    NASA Astrophysics Data System (ADS)

    Fang, Shu-Hwei; Chen, Hsiung-Wen

    Due to limited land and great emphasis on economic growth in the past, Taiwan has an extremely heavy environmental burden. Population density, factory density, as well as densities of motor vehicles are several times higher than those in the United States and Japan. According to the statistics of 1991, the Pollutant Standards Index (PSI) fell mostly in the "moderate" category, i.e., in the range of 50-100. There were 16.25% of the monitored days with PSI above 100, and 0.51% with PSI beyond 200. Suspended particulates were the major pollutant responsible for PSI above 100, followed by carbon monoxide, ozone, and sulfur dioxide. The measures adopted to control air pollution can be divided into four categories, namely law and regulations, control measures on stationary sources, mobile sources and construction projects. The latest amended Air Pollution Control Act was promulgated on 1 February 1992. Several major revisions were introduced to make the amended Act much more stringent than the 1982 amendment, especially on the offenses likely to endanger public health and welfare. In regard to stationary sources, a permit system was enacted to regulate the establishment and alteration of stationary sources. Designated stationary sources are required to be equipped with automatic monitoring facilities. An inspection and enforcement program have expanded to cover more than 10,000 factories. Major control measures for motor vehicles include introducing stringent emission standards for gasoline-fueled vehicles and diesel cars, setting up ratification and approval program for new vehicle model, promoting the inspection/maintenance program on in-used motorcycles and encouraging the use of unleaded and low sulfur fuels. In order to control the pollution caused by construction work, constructors are required to use low-pollution machinery and engineering methods and incorporate pollution prevention into the construction budget.

  3. Plug valve

    DOEpatents

    Wordin, John J.

    1989-01-01

    An improved plug valve wherein a novel shape for the valve plug and valve chamber provide mating surfaces for improved wear characteristics. The novel shape of the valve plug is a frustum of a body of revolution of a curved known as a tractrix, a solid shape otherwise known as a peudosphere.

  4. [Air quality control systems: heating, ventilating, and air conditioning (HVAC)].

    PubMed

    Bellucci Sessa, R; Riccio, G

    2004-01-01

    After a brief illustration of the principal layout schemes of Heating, Ventilating, and Air Conditioning (HVAC), the first part of this paper summarizes the standards, both voluntary and compulsory, regulating HVAC facilities design and installation with regard to the question of Indoor Air Quality (IAQ). The paper then examines the problem of ventilation systems maintenance and the essential hygienistic requirements in whose absence HVAC facilities may become a risk factor for people working or living in the building. Lastly, the paper deals with HVAC design strategies and methods, which aim not only to satisfy comfort and air quality requirements, but also to ensure easy and effective maintenance procedures.

  5. Electric controlled air incinerator for radioactive wastes

    DOEpatents

    Warren, Jeffery H.; Hootman, Harry E.

    1981-01-01

    A two-stage incinerator is provided which includes a primary combustion chamber and an afterburner chamber for off-gases. The latter is formed by a plurality of vertical tubes in combination with associated manifolds which connect the tubes together to form a continuous tortuous path. Electrically-controlled heaters surround the tubes while electrically-controlled plate heaters heat the manifolds. A gravity-type ash removal system is located at the bottom of the first afterburner tube while an air mixer is disposed in that same tube just above the outlet from the primary chamber. A ram injector in combination with rotary magazine feeds waste to a horizontal tube forming the primary combustion chamber.

  6. Jet-controlled freeze valve for use in a glass melter

    DOEpatents

    Routt, K.R.

    1985-07-29

    A drain valve for use in furnace for the melting of thermoplastic material is disclosed. The furnace includes a drain cavity formed in its bottom for withdrawing a flow of thermoplastic material. The drain valve includes a flow member which include a flow tube having an inlet and outlet for the material, and coaxially disposed concentric tubular members defining annuli surrounding the flow tube. The tubular members include heating and cooling means for the flow tube. The drain valve can also be used in a furnace of glass melting that includes a drain cavity for withdrawing molten glass from the furnace.

  7. Solid handling valve

    DOEpatents

    Williams, William R.

    1979-01-01

    The present invention is directed to a solids handling valve for use in combination with lock hoppers utilized for conveying pulverized coal to a coal gasifier. The valve comprises a fluid-actuated flow control piston disposed within a housing and provided with a tapered primary seal having a recessed seat on the housing and a radially expandable fluid-actuated secondary seal. The valve seals are highly resistive to corrosion, erosion and abrasion by the solids, liquids, and gases associated with the gasification process so as to minimize valve failure.

  8. Heimlich valve and pneumothorax

    PubMed Central

    Gogakos, Apostolos; Barbetakis, Nikolaos; Lazaridis, George; Papaiwannou, Antonis; Karavergou, Anastasia; Lampaki, Sofia; Baka, Sofia; Mpoukovinas, Ioannis; Karavasilis, Vasilis; Kioumis, Ioannis; Pitsiou, Georgia; Katsikogiannis, Nikolaos; Tsakiridis, Kosmas; Rapti, Aggeliki; Trakada, Georgia; Zissimopoulos, Athanasios; Tsirgogianni, Katerina; Zarogoulidis, Konstantinos

    2015-01-01

    The Heimlich valve is a small one-way valve used for chest drainage that empties into a flexible collection device and prevents return of gases or fluids into the pleural space. The Heimlich valve is less than 13 cm (5 inches) long and facilitates patient ambulation. Currently there are several systems in the market. It can be used in many patients instead of a traditional water seal drainage system. The Heimlich chest drainage valve was developed so that the process of draining the pleural cavity could be accomplished in a safe, relatively simple, and efficient manner. This valve system has replaced the cumbersome underwater drainage bottle system. Moreover; the Heimlich valve system connects to chest tubing and allows fluid and air to pass in one direction only. This system functions in any position, and it does not ever need to be clamped, a regulated suction can be attached to it if necessary. The valve drains into a plastic bag that can be held at any level, allowing the patient undergoing chest drainage to be ambulatory simply by carrying the bag. In the current mini review we will present the Heimlich valve system and method of insertion. PMID:25861609

  9. 75 FR 18142 - Approval and Promulgation of Air Quality Implementation Plans; Texas; Control of Air Pollution...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-09

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Texas; Control of Air Pollution From Motor Vehicles AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule... Title 30 of the Texas Administrative Code (TAC), Chapter 114, Control of Air Pollution from...

  10. 78 FR 58460 - Revision of Air Quality Implementation Plan; California; Placer County Air Pollution Control...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-24

    ... Pollution Control District and Feather River Air Quality Management District; Stationary Source Permits... California as a revision to the Placer County Air Pollution Control District (PCAPCD) and Feather River Air Quality Management District (FRAQMD) portion of the California State Implementation Plan (SIP)....

  11. 49 CFR 179.400-19 - Valves and gages.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... liquid flow rates. All valves must be made from approved materials compatible with the lading and having... 49 Transportation 2 2010-10-01 2010-10-01 false Valves and gages. 179.400-19 Section 179.400-19...-19 Valves and gages. (a) Valves. Manually operated shut-off valves and control valves must...

  12. Controlling Urban Air Pollution: A Benefit-Cost Assessment.

    ERIC Educational Resources Information Center

    Krupnick, Alan J.; Portney, Paul R.

    1991-01-01

    The pros and cons of air pollution control efforts are discussed. Both national and regional air pollution control plans are described. Topics of discussion include benefit-cost analysis, air quality regulation, reducing ozone in the urban areas, the Los Angeles plan, uncertainties, and policy implications. (KR)

  13. 5 CFR 842.207 - Air traffic controllers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Air traffic controllers. 842.207 Section... (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-BASIC ANNUITY Eligibility § 842.207 Air traffic controllers... misconduct, is entitled to an annuity— (1) After completing 25 years of service as an air traffic...

  14. 5 CFR 842.207 - Air traffic controllers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Air traffic controllers. 842.207 Section... (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-BASIC ANNUITY Eligibility § 842.207 Air traffic controllers... misconduct, is entitled to an annuity— (1) After completing 25 years of service as an air traffic...

  15. 5 CFR 842.207 - Air traffic controllers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Air traffic controllers. 842.207 Section... (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-BASIC ANNUITY Eligibility § 842.207 Air traffic controllers... misconduct, is entitled to an annuity— (1) After completing 25 years of service as an air traffic...

  16. 14 CFR 25.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Carburetor air temperature controls. 25.1157 Section 25.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 25.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  17. 14 CFR 25.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Carburetor air temperature controls. 25.1157 Section 25.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 25.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  18. 14 CFR 25.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Carburetor air temperature controls. 25.1157 Section 25.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 25.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  19. 14 CFR 25.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Carburetor air temperature controls. 25.1157 Section 25.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 25.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  20. 14 CFR 29.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Carburetor air temperature controls. 29.1157 Section 29.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 29.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  1. 14 CFR 29.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Carburetor air temperature controls. 29.1157 Section 29.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 29.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  2. 14 CFR 25.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Carburetor air temperature controls. 25.1157 Section 25.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 25.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  3. 14 CFR 29.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Carburetor air temperature controls. 29.1157 Section 29.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 29.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  4. 14 CFR 29.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Carburetor air temperature controls. 29.1157 Section 29.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 29.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  5. 14 CFR 29.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Carburetor air temperature controls. 29.1157 Section 29.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 29.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  6. 5 CFR 842.207 - Air traffic controllers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Air traffic controllers. 842.207 Section... (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-BASIC ANNUITY Eligibility § 842.207 Air traffic controllers... misconduct, is entitled to an annuity— (1) After completing 25 years of service as an air traffic...

  7. Simple, Internally Adjustable Valve

    NASA Technical Reports Server (NTRS)

    Burley, Richard K.

    1990-01-01

    Valve containing simple in-line, adjustable, flow-control orifice made from ordinary plumbing fitting and two allen setscrews. Construction of valve requires only simple drilling, tapping, and grinding. Orifice installed in existing fitting, avoiding changes in rest of plumbing.

  8. Valve for abrasive material

    DOEpatents

    Gardner, Harold S.

    1982-01-01

    A ball valve assembly for controlling the flow of abrasive particulates including an enlarged section at the bore inlet and an enlarged section at the bore outlet. A refractory ceramic annular deflector is positioned in each of the enlarged sections, substantially extending the useful life of the valve.

  9. Check valve

    DOEpatents

    Upton, Hubert Allen; Garcia, Pablo

    1999-08-24

    A check valve for use in a GDCS of a nuclear reactor and having a motor driven disk including a rotatable armature for rotating the check valve disk over its entire range of motion is described. In one embodiment, the check valve includes a valve body having a coolant flow channel extending therethrough. The coolant flow channel includes an inlet end and an outlet end. A valve body seat is located on an inner surface of the valve body. The check valve further includes a disk assembly, sometimes referred to as the motor driven disc, having a counterweight and a disk shaped valve. The disk valve includes a disk base having a seat for seating with the valve body seat. The disk assembly further includes a first hinge pin member which extends at least partially through the disk assembly and is engaged to the disk. The disk valve is rotatable relative to the first hinge pin member. The check valve also includes a motor having a stator frame with a stator bore therein. An armature is rotatably positioned within the stator bore and the armature is coupled to the disk valve to cause the disk valve to rotate about its full range of motion.

  10. Check valve

    DOEpatents

    Upton, H.A.; Garcia, P.

    1999-08-24

    A check valve for use in a GDCS of a nuclear reactor and having a motor driven disk including a rotatable armature for rotating the check valve disk over its entire range of motion is described. In one embodiment, the check valve includes a valve body having a coolant flow channel extending therethrough. The coolant flow channel includes an inlet end and an outlet end. A valve body seat is located on an inner surface of the valve body. The check valve further includes a disk assembly, sometimes referred to as the motor driven disc, having a counterweight and a disk shaped valve. The disk valve includes a disk base having a seat for seating with the valve body seat. The disk assembly further includes a first hinge pin member which extends at least partially through the disk assembly and is engaged to the disk. The disk valve is rotatable relative to the first hinge pin member. The check valve also includes a motor having a stator frame with a stator bore therein. An armature is rotatably positioned within the stator bore and the armature is coupled to the disk valve to cause the disk valve to rotate about its full range of motion. 5 figs.

  11. Controlling air toxics through advanced coal preparation

    SciTech Connect

    Straszheim, W.E.; Buttermore, W.H.; Pollard, J.L.

    1995-11-01

    This project involves the assessment of advanced coal preparation methods for removing trace elements from coal to reduce the potential for air toxic emissions upon combustion. Scanning electron microscopy-based automated image analysis (SEM-AIA) and advanced washability analyses are being applied with state-of-the-art analytical procedures to predict the removal of elements of concern by advanced column flotation and to confirm the effectiveness of preparation on the quality of quantity of clean coal produced. Specific objectives are to maintain an acceptable recovery of combustible product, while improving the rejection of mineral-associated trace elements. Current work has focused on determining conditions for controlling column flotation system across its operating range and on selection and analysis of samples for determining trace element cleanability.

  12. DETAIL, CONTROL BOOTH, RP1 TANK FARM Edwards Air Force ...

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

    DETAIL, CONTROL BOOTH, RP1 TANK FARM - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Combined Fuel Storage Tank Farm, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  13. Lightweight Valve Closes Duct Quickly

    NASA Technical Reports Server (NTRS)

    Fournier, Walter L.; Burgy, N. Frank

    1991-01-01

    Expanding balloon serves as lightweight emergency valve to close wide duct. Uninflated balloon stored in housing of duct. Pad resting on burst diaphragm protects balloon from hot gases in duct. Once control system triggers valve, balloon inflates rapidly to block duct. Weighs much less than does conventional butterfly, hot-gas, or poppet valve capable of closing duct of equal diameter.

  14. Simulation and experimental control of a 3-RPR parallel robot using optimal fuzzy controller and fast on/off solenoid valves based on the PWM wave.

    PubMed

    Moezi, Seyed Alireza; Rafeeyan, Mansour; Zakeri, Ehsan; Zare, Amin

    2016-03-01

    In this paper, a robust optimal fuzzy controller based on the Pulse Width Modulation (PWM) technique is proposed to control a laboratory parallel robot using inexpensive on/off solenoid valves. The controller coefficients are determined using Modified Cuckoo Optimization Algorithm. The objective function of this method is considered such that the results show the position tracking by the robot with less force and more efficiency. Regarding the results of experimental tests, the control strategy with on/off valves indicates good performance such that the maximum value of RMS of error for a circular path with increasing force on the system is 3.1mm. Furthermore, the results show the superiority of the optimal fuzzy controller compared with optimal PID controller in tracking paths with different conditions and uncertainties. PMID:26794489

  15. Automatic monitoring of valve status

    SciTech Connect

    Prinz, F.B.; Chern, J.H.

    1989-06-01

    Authors propose establishing the relationship between valve leaking and thermal gradient to allow detection of valve leakage by observing the piping system`s temperature profile and using an expert system to infer the valve condition. They describe their work toward this and their January 1988 report thereon. The authors also suggest designing modem power plants to accommodate a remotely controlled or autonomous vehicle which would carry a device for thermal-gradient leak detection to examine valves in situ.

  16. Theoretical analysis of a pressure setting and control system with PWM direction control valve

    NASA Astrophysics Data System (ADS)

    Avram, M.; Duminică, D.; Cartal, L. A.

    2016-08-01

    The paper tackles theoretical aspects concerning an original automated system that sets and controls the pressure inside a tank chamber of fixed volume. The structure of the system integrates an original device developed and designed by the authors. The device digitally controls the one way flow of the working fluid using pulse width modulation, allowing the free flow in the other way. The purpose of this research stage was the theoretical establishing of the variation law of the pressure inside the controlled chamber.

  17. Space Vehicle Valve System

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R. (Inventor); Lindner, Jeffrey L. (Inventor)

    2014-01-01

    The present invention is a space vehicle valve system which controls the internal pressure of a space vehicle and the flow rate of purged gases at a given internal pressure and aperture site. A plurality of quasi-unique variable dimension peaked valve structures cover the purge apertures on a space vehicle. Interchangeable sheet guards configured to cover valve apertures on the peaked valve structure contain a pressure-activated surface on the inner surface. Sheet guards move outwardly from the peaked valve structure when in structural contact with a purge gas stream flowing through the apertures on the space vehicle. Changing the properties of the sheet guards changes the response of the sheet guards at a given internal pressure, providing control of the flow rate at a given aperture site.

  18. Apparatus and method for non-invasive diagnosis and control of motor operated valve condition

    DOEpatents

    Lyon, Richard H.; Chai, Jangbom; Lang, Jeffrey H.; Hagman, Wayne H.; Umans, Stephen D.; Saarela, Olli J.

    1997-01-01

    An apparatus compares the torque from an MOV motor with the valve displacement, and from the comparison assesses MOV operating condition. A transducer measures the vibration of the housing of an MOV. The vibrations are due to the motions of the rotating elements within the housing, which motions are directly related to the motion of the valve relative to its seat. Signal processing apparatus analyzes the vibrations to recover the rotations of the rotating elements and thus the motion of the valve plug. Lost motion can also be determined (if a lost motion connection exists) by demodulating the vibration signal and thus taking into account also the lost motion. Simultaneously, the forces applied to the valve are estimated by estimating the torque between the stator and the rotor of the motor. Such torque can be estimated from measuring the input current and voltage alone, using a forgetting factor and a correction for the forgetting factor. A signature derived from relating the torque to the valve position can be used to assess the condition of the MOV, by comparing the signature to signatures for MOVs of known conditions. The vibration analysis components generate signals that relate to the position of elements in the operator. Similarly, the torque estimator estimates the torque output by any type of electric motor, whether or not part of an MOV analysis unit.

  19. Apparatus and method for non-invasive diagnosis and control of motor operated valve condition

    DOEpatents

    Lyon, R.H.; Chai, J.; Lang, J.H.; Hagman, W.H.; Umans, S.D.; Saarela, O.J.

    1997-01-14

    An apparatus compares the torque from an MOV motor with the valve displacement, and from the comparison assesses MOV operating condition. A transducer measures the vibration of the housing of an MOV. The vibrations are due to the motions of the rotating elements within the housing, which motions are directly related to the motion of the valve relative to its seat. Signal processing apparatus analyzes the vibrations to recover the rotations of the rotating elements and thus the motion of the valve plug. Lost motion can also be determined (if a lost motion connection exists) by demodulating the vibration signal and thus taking into account also the lost motion. Simultaneously, the forces applied to the valve are estimated by estimating the torque between the stator and the rotor of the motor. Such torque can be estimated from measuring the input current and voltage alone, using a forgetting factor and a correction for the forgetting factor. A signature derived from relating the torque to the valve position can be used to assess the condition of the MOV, by comparing the signature to signatures for MOVs of known conditions. The vibration analysis components generate signals that relate to the position of elements in the operator. Similarly, the torque estimator estimates the torque output by any type of electric motor, whether or not part of an MOV analysis unit. 28 figs.

  20. Valve Disease

    MedlinePlus

    ... the need for heart valve surgery. Percutaneous Interventions Balloon valvuloplasty is a procedure that may be used ... procedure works on valves in the same way balloon angioplasty does on the arteries. Like angioplasty, it ...

  1. Internal combustion engine control system

    SciTech Connect

    Lambert, J.E.

    1989-12-12

    This patent describes an internal combustion engine control system apparatus. It comprises: carburetor venturi means flowing basic combustion air and having a induced fuel flow in the basic combustion air; carburetor by pass throttle valve means having a biased open position and causing and trimming the flow of supplementary combustion air parallel to and then into the basic combustion air for mixing; engine throttle valve means regulating the flow of a mixture of the supplementary combustion air and the basic combustion air with induced fuel flow for engine combustion; Separate electrical step motor means connected to the carburetor by-pass throttle valve means and to the engine throttle valve means; and pre-programmed microprocessor means connected to each of the electrical stepmotor means. The microprocessor means controlling one of the electrical stepmotor means and the trim positioning of the carburetor by-pass throttle valve means in response to sensed engine speed and sensed engine manifold pressure or throttle position conditions.

  2. Multi-port valve

    DOEpatents

    Lewin, Keith F.

    1997-04-15

    A multi-port valve for regulating, as a function of ambient air having varying wind velocity and wind direction in an open-field control area, the distribution of a fluid, particularly carbon dioxide (CO.sub.2) gas, in a fluid distribution system so that the control area remains generally at an elevated fluid concentration or level of said fluid. The multi-port valve generally includes a multi-port housing having a plurality of outlets therethrough disposed in a first pattern of outlets and at least one second pattern of outlets, and a movable plate having a plurality of apertures extending therethrough disposed in a first pattern of apertures and at least one second pattern of apertures. The first pattern of apertures being alignable with the first pattern of outlets and the at least one second pattern of apertures being alignable with the second pattern of outlets. The first pattern of apertures has a predetermined orientation with the at least one second pattern of apertures. For an open-field control area subject to ambient wind having a low velocity from any direction, the movable plate is positioned to equally distribute the supply of fluid in a fluid distribution system to the open-field control area. For an open-field control area subject to ambient wind having a high velocity from a given direction, the movable plate is positioned to generally distribute a supply of fluid in a fluid distribution system to that portion of the open-field control area located upwind.

  3. Multi-port valve

    DOEpatents

    Lewin, K.F.

    1997-04-15

    A multi-port valve is described for regulating, as a function of ambient air having varying wind velocity and wind direction in an open-field control area, the distribution of a fluid, particularly carbon dioxide (CO{sub 2}) gas, in a fluid distribution system so that the control area remains generally at an elevated fluid concentration or level of said fluid. The multi-port valve generally includes a multi-port housing having a plurality of outlets there through disposed in a first pattern of outlets and at least one second pattern of outlets, and a movable plate having a plurality of apertures extending there through disposed in a first pattern of apertures and at least one second pattern of apertures. The first pattern of apertures being alignable with the first pattern of outlets and the at least one second pattern of apertures being alignable with the second pattern of outlets. The first pattern of apertures has a predetermined orientation with the at least one second pattern of apertures. For an open-field control area subject to ambient wind having a low velocity from any direction, the movable plate is positioned to equally distribute the supply of fluid in a fluid distribution system to the open-field control area. For an open-field control area subject to ambient wind having a high velocity from a given direction, the movable plate is positioned to generally distribute a supply of fluid in a fluid distribution system to that portion of the open-field control area located upwind. 7 figs.

  4. Bypass valve and coolant flow controls for optimum temperatures in waste heat recovery systems

    DOEpatents

    Meisner, Gregory P

    2013-10-08

    Implementing an optimized waste heat recovery system includes calculating a temperature and a rate of change in temperature of a heat exchanger of a waste heat recovery system, and predicting a temperature and a rate of change in temperature of a material flowing through a channel of the waste heat recovery system. Upon determining the rate of change in the temperature of the material is predicted to be higher than the rate of change in the temperature of the heat exchanger, the optimized waste heat recovery system calculates a valve position and timing for the channel that is configurable for achieving a rate of material flow that is determined to produce and maintain a defined threshold temperature of the heat exchanger, and actuates the valve according to the calculated valve position and calculated timing.

  5. APEX (Air Pollution Exercise) Volume 3: Air Pollution Control Officer's Manual.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Research Triangle Park, NC. Office of Manpower Development.

    The Air Pollution Control Officer's (APCO) Manual is part of a set of 21 manuals (AA 001 009-001 029) used in APEX (Air Pollution Exercise) a computerized college and professional level "real world" game simulation of a community with urban and rural problems, industrial activities, and air pollution difficulties, The first two sections, which are…

  6. APEX (Air Pollution Exercise) Volume 21: Legal References: Air Pollution Control Regulations.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Research Triangle Park, NC. Office of Manpower Development.

    The Legal References: Air Pollution Control Regulations Manual is the last in a set of 21 manuals (AA 001 009-001 029) used in APEX (Air Pollution Exercise), a computerized college and professional level "real world" game simulation of a community with urban and rural problems, industrial activities, and air pollution difficulties. The manual…

  7. Atlanta Air Route Traffic Control Center's involvement in aviation weather

    NASA Technical Reports Server (NTRS)

    Wood, W. D.

    1979-01-01

    The distribution of weather information throughout the Air Traffic Control System is discussed along with the development of meteorological radar, and the modifications to the Air Route Traffic Control Center radars for locating and determining the severity of storms' cells. The planned improvements in the availability of weather data to the control centers are listed.

  8. Valve selection in aortic valve endocarditis

    PubMed Central

    Zubrytska, Yana

    2016-01-01

    Aortic prosthetic valve endocarditis (PVE) is a potentially life-threatening disease. Mortality and incidence of infective endocarditis have been reduced in the past 30 years. Medical treatment of aortic PVE may be successful in patients who have a prompt response after antibiotic treatment and who do not have prosthetic dysfunction. In advanced stages, antibiotic therapy alone is insufficient to control the disease, and surgical intervention is necessary. Surgical treatment may be lifesaving, but it is still associated with considerable morbidity and mortality. The aim of surgery is to perform a radical excision of all infected and necrotic tissue, reconstruction of the left ventricle outflow tract, and replacement of the aortic valve. There is no unanimous consensus on which is the optimal prosthesis to implant in this context, and several surgical techniques have been suggested. We aim to analyze the efficacy of the surgical treatment and discuss the issue of valve selection in patients with aortic valve endocarditis. PMID:27785132

  9. Passive control of VOCs using valved well heads: FY1994 report

    SciTech Connect

    Rossabi, J.; Riha, B.D.

    1994-10-27

    The data described in this report were collected as part of a project to explore the viability of passive soil vapor extraction techniques for removal of volatile organic contaminants from the subsurface. The principal objectives of this project are to determine the mechanism and physical dynamics of the relationship between surface atmospheric pressure and subsurface flow and contaminant transport, and to use this information to design cost effective and efficient remediation systems. This work is funded under the Volatile Organic Compounds - Arid Integrated Demonstration (VOC - Arid ID). The purpose of the VOC - Arid ID is to identify, develop, and demonstrate technologies that may be used to characterize, remediate, and/or monitor and or semiarid sites containing VOC (e.g., carbon tetrachloride and trichloroethylene [TCE]) with or without associated metal and radionuclide contamination. The results from this project are applicable at arid, semi-arid, and non-arid sites. This report documents the methods and findings from the Savannah River Site barometric pumping study. The results in this report include: (1) Surface and subsurface pressure measurements and analysis results from the Savannah River Integrated Demonstration Site (SRIDS). (2) Barometric pumping flow data measured and/or estimated from several wells. (3) Continuous concentration and flow data from one well. (4) development of two computer models that can predict either subsurface pressure or the effective cumulative permeability of the formation in the vertical direction from surface atmospheric pressure data. (5) The derivation of the analytical computer models, the executable code on disk, and written documentation for using the models including examples. The optimization of barometric removal rates using an innovative control valve and the implications of this data for passive extraction systems are discussed.

  10. 100. INTERIOR OF SKID 9A: VENT VALVE AND RELIEF VALVE ...

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

    100. INTERIOR OF SKID 9A: VENT VALVE AND RELIEF VALVE FOR RAPID-LOAD LIQUID OXYGEN TANK - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  11. Heart valve surgery

    MedlinePlus

    Valve replacement; Valve repair; Heart valve prosthesis; Mechanical valves, Prosthetic valves ... place. The main types of new valves are: Mechanical -- made of man-made materials, such as metal ( ...

  12. Controlling Air Pollution; A Primer on Stationary Source Control Techniques.

    ERIC Educational Resources Information Center

    Corman, Rena

    This companion document to "Air Pollution Primer" is written for the nonexpert in air pollution; however, it does assume a familiarity with air pollution problems. This work is oriented toward providing the reader with knowledge about current and proposed air quality legislation and knowledge about available technology to meet these standards for…

  13. Development of a new combined test setup for accelerated dynamic pH-controlled in vitro calcification of porcine heart valves.

    PubMed

    Kriegs, Martin; Kanellopoulou, Dimitra; Koutsoukos, Petros G; Mavrilas, Dimosthenis; Glasmacher, Birgit

    2009-11-01

    Fifty years after their first implantation, bioprosthetic heart valves still suffer from tissue rupture and calcification. Since new bioprostheses exhibit a lower risk of calcification, fast and reliable in vitro methods need to be evaluated for testing the application of new anti-calcification techniques. This report describes a modification of the well-known in vitro dynamic calcification test method (Glasmacher et al, Leibniz University Hannover (LUH)), combined with the pH-controlled, constant solution supersaturation (CSS) method (University of Patras (UP)). The CSS method is based on monitoring the pH of the solution and the addition of calcium and phosphate ion solutions through the implementation of two syringe pumps. The pH and the activities of all ions in the solutions are thus kept constant, resulting in higher calcification rates compared to conventional in vitro methods in which solution supersaturation is allowed to decrease without any further control. To verify this hypothesis, five glutaraldehyde preserved porcine aortic valves were tested. Three of the valves were tested according to a free-drift methodology: the valves were immersed in a supersaturated calcification solution, with an initial total calcium times total phosphate product of (CaxP)=10.5 (mmol/L)2, renewed weekly. Two valves were tested by the new pH-controlled loop system, implementing the CSS methodology. All valves were tested for a 4-week period, loaded at 300 cycles per minute, resulting in a total of 12 million cycles at the end of the testing period. The degree of calcification was determined weekly by means of mux-ray, and by conventional, clinical and micro-computer tomography (CT, muCT). The results showed that the valves mineralizing at constant solution supersaturation in vitro yielded higher rates of calcification compared to the valves tested at conditions of decreasing solution supersaturation without any control, indicating the development of a new, accelerated

  14. Integrating bio-prosthetic valves in the Fontan operation - Novel treatment to control retrograde flow in caval veins

    NASA Astrophysics Data System (ADS)

    Vukicevic, Marija; Conover, Timothy; Zhou, Jian; Hsia, Tain-Yen; Figliola, Richard

    2012-11-01

    For a child born with only one functional heart ventricle, the sequence of palliative surgeries typically culminates in the Fontan operation. This procedure is usually successful initially, but leads to later complications, for reasons not fully understood. Examples are respiratory-dependent retrograde flows in the caval and hepatic veins, and increased pulmonary vascular resistance (PVR), hypothesized to be responsible for elevated pressure in the liver and disease of the liver and intestines. Here we study the parameters responsible for retrograde flows in the inferior vena cava (IVC) and hepatic vein (HV), and investigate two novel interventions to control retrograde flow: implanting either a Medtronic Contegra valved conduit or an Edwards lifescience pericardial aortic valve in the IVC or HV. We performed the experiments in a multi-scale, patient specific mock circuit, with normal and elevated PVR, towards the optimization of the Fontan circulation. The results show that both valves can significantly reduce retrograde flows in the veins, suggesting potential advantages in the treatment of the patients with congenital heart diseases. Fondation Leducq

  15. Valve Repair or Replacement

    MedlinePlus

    ... valve surgery can be done using a robot. Robotic surgery does not require a large incision in ... The Texas Heart Institute has a robot. With robotic surgery, the surgeon has a control console, a ...

  16. THERMALLY OPERATED VAPOR VALVE

    DOEpatents

    Dorward, J.G. Jr.

    1959-02-10

    A valve is presented for use in a calutron to supply and control the vapor to be ionized. The invention provides a means readily operable from the exterior of the vacuum tank of the apparatuss without mechanical transmission of forces for the quick and accurate control of the ionizing arc by a corresponding control of gas flow theretos thereby producing an effective way of carefully regulating the operation of the calutron. The invention consists essentially of a tube member extending into the charge bottle of a calutron devices having a poppet type valve closing the lower end of the tube. An electrical heating means is provided in the valve stem to thermally vary the length of the stem to regulate the valve opening to control the flow of material from the charge bottle.

  17. 14 CFR 125.133 - Fuel valves.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Fuel valves. 125.133 Section 125.133 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS....133 Fuel valves. Each fuel valve must— (a) Comply with § 125.155; (b) Have positive stops or...

  18. 14 CFR 125.133 - Fuel valves.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Fuel valves. 125.133 Section 125.133 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS....133 Fuel valves. Each fuel valve must— (a) Comply with § 125.155; (b) Have positive stops or...

  19. 14 CFR 125.133 - Fuel valves.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Fuel valves. 125.133 Section 125.133 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS....133 Fuel valves. Each fuel valve must— (a) Comply with § 125.155; (b) Have positive stops or...

  20. Valve for fuel pin loading system

    DOEpatents

    Christiansen, D.W.

    1984-01-01

    A cyclone valve surrounds a wall opening through which cladding is projected. An axial valve inlet surrounds the cladding. Air is drawn through the inlet by a cyclone stream within the valve. An inflatable seal is included to physically engage a fuel pin subassembly during loading of fuel pellets.

  1. Internal combustion engine with rotary valve assembly having variable intake valve timing

    DOEpatents

    Hansen, Craig N.; Cross, Paul C.

    1995-01-01

    An internal combustion engine has rotary valves associated with movable shutters operable to vary the closing of intake air/fuel port sections to obtain peak volumetric efficiency over the entire range of speed of the engine. The shutters are moved automatically by a control mechanism that is responsive to the RPM of the engine. A foot-operated lever associated with the control mechanism is also used to move the shutters between their open and closed positions.

  2. Air stripping of contaminated water sources - air emissions and controls. Final report

    SciTech Connect

    Vancit, M.A.; Howle, R.H.; Herndon, D.J.; Shareef, S.A.

    1987-08-01

    Air-stripping towers are being used to remove low concentrations of organic contaminants from water. The report describes the technology and methods used to control air pollution resulting from this procedure. The cost of the controls is presented along with other positive and negative impacts of the technology.

  3. In vitro comparison tests of three LV vent valves.

    PubMed

    Lewis, G S; Czaplicka, C

    1990-01-01

    Many surgical teams employ a sump pump to vent the left ventricle (LV). The problems associated with this technique are related to safety and convenience. If the flow is accidentally reversed in the LV vent line, air embolism accidents and subsequent litigation may be the result. If the cannula is occluded, it is inconvenient to juggle pump speed to prevent the line from collapsing while maintaining gentle but adequate suction. In this study we in vitro tested three commercially available LV vent valves (RLV-2100 "B," VRV-200 B, H-130) (GLV did not wish to send samples for comparison at the time of this study). Each valve was designed to: regulate suction in the LV vent line; prevent the flow of air towards the heart; and vent downstream pressure to the atmosphere. Each valve was tested for suction at various flow rates, pressure heads, and for the presence of air leakage during reversed flow conditions. The results of pressure and suction tests during normal flow and occluded line conditions have been tabulated. We found the RLV-2100 "B" offers the safest combination of suction control and pressure relief. The most astonishing fact learned was the RLV-2100 "B" was the only valve which prevented the flow of air towards the heart during reversed flow. As a result, we elected to use only this valve in our clinical practice.

  4. Air-fuel mixture ratio control using electrostatic force

    SciTech Connect

    Maruoka, H.

    1981-07-28

    Electrostatically charged liquid fuel is introduced into a venturi to be atomized therein and is then applied to the combustion chamber of an engine under the control of electrostatic force for properly controlling the air-fuel mixture ratio.

  5. Air-fuel mixture ratio control using electrostatic force

    SciTech Connect

    Maruoka, H.

    1980-01-15

    Electrostatically charged liquid fuel is introduced into a venturi to be atomized therein and is then applied to the combustion chambers of an engine under the control of electrostatic force for properly controlling the air-fuel mixture ratio.

  6. CONTROL BUILDING, WEST FRONT SHOWING ENTRANCE Edwards Air Force ...

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

    CONTROL BUILDING, WEST FRONT SHOWING ENTRANCE - Edwards Air Force Base, X-15 Engine Test Complex, Firing Control Building, Rogers Dry Lake, east of runway between North Base & South Base, Boron, Kern County, CA

  7. Efficient Conversation: The Talk between Pilots and Air Traffic Controllers.

    ERIC Educational Resources Information Center

    Simmons, James L.

    Two-way radio communications between air traffic controllers using radar on the ground to give airplane pilots instructions are of interest within the developing framework of the sociology of language. The main purpose of air traffic control language is efficient communication to promote flight safety. This study describes the standardized format…

  8. Combustion engine. [for air pollution control

    NASA Technical Reports Server (NTRS)

    Houseman, J. (Inventor)

    1977-01-01

    An arrangement for an internal combustion engine is provided in which one or more of the cylinders of the engine are used for generating hydrogen rich gases from hydrocarbon fuels, which gases are then mixed with air and injected into the remaining cylinders to be used as fuel. When heavy load conditions are encountered, hydrocarbon fuel may be mixed with the hydrogen rich gases and air and the mixture is then injected into the remaining cylinders as fuel.

  9. Depressurization valve

    DOEpatents

    Skoda, G.I.

    1989-03-28

    A depressurization valve for use in relieving completely the pressure in a simplified boiling water reactor is disclosed. The normally closed and sealed valve is provided with a valve body defining a conduit from an outlet of a manifold from the reactor through a valve seat. A closing valve disk is configured for fitting to the valve seat to normally close the valve. The seat below the disk is provided with a radially extending annulus extending a short distance into the aperture defined by the seat. The disk is correspondingly provided with a longitudinally extending annulus that extends downwardly through the aperture defined by the seat towards the high pressure side of the valve body. A ring shaped membrane is endlessly welded to the seat annulus and to the disk annulus. The membrane is conformed over the confronted surface of the seat and disk in a C-sectioned configuration to seal the depressurization valve against the possibility of weeping. The disk is held to the closed position by an elongate stem extending away from the high pressure side of the valve body. The stem has a flange configured integrally to the stem for bias by two springs. The first spring acts from a portion of the housing overlying the disk on the stem flange adjacent the disk. This spring urges the stem and attached disk away from the seat and thus will cause the valve to open at any pressure. A second spring-preferably of the Belleville variety-acts on a latch plate surrounding and freely moving relative to the end of the stem. This second spring overcomes the bias of the first spring and any pressure acting upon the disk. This Belleville spring maintains through its spring force the valve in the closed position. At the same time, the latch plate with its freedom of movement relative to the stem allows the stem to thermally expand during valve temperature excursion.

  10. Multi-port valve assembly

    DOEpatents

    Guggenheim, S. Frederic

    1986-01-01

    A multi-port fluid valve apparatus is used to control the flow of fluids through a plurality of valves and includes a web, which preferably is a stainless steel endless belt. The belt has an aperture therethrough and is progressed, under motor drive and control, so that its aperture is moved from one valve mechanism to another. Each of the valve mechanisms comprises a pair of valve blocks which are held in fluid-tight relationship against the belt. Each valve block consists of a block having a bore through which the fluid flows, a first seal surrounding the bore and a second seal surrounding the first seal, with the distance between the first and second seals being greater than the size of the belt aperture. In order to open a valve, the motor progresses the belt aperture to where it is aligned with the two bores of a pair of valve blocks, such alignment permitting a flow of the fluid through the valve. The valve is closed by movement of the belt aperture and its replacement, within the pair of valve blocks, by a solid portion of the belt.

  11. Intraocular pressure control after the implantation of a second Ahmed glaucoma valve.

    PubMed

    Jiménez-Román, Jesús; Gil-Carrasco, Félix; Costa, Vital Paulino; Schimiti, Rui Barroso; Lerner, Fabián; Santana, Priscila Rezende; Vascocellos, Jose Paulo Cabral; Castillejos-Chévez, Armando; Turati, Mauricio; Fabre-Miranda, Karina

    2016-06-01

    The objective of this study is to evaluate the efficacy and safety of a second Ahmed glaucoma valve (AGV) in eyes with refractory glaucoma that had undergone prior Ahmed device implantation. This multicenter, retrospective study evaluated 58 eyes (58 patients) that underwent a second AGV (model S2-n = 50, model FP7-n = 8) due to uncontrolled IOP under maximal medical therapy. Outcome measures included IOP, visual acuity, number of glaucoma medications, and postoperative complications. Success was defined as IOP <21 mmHg (criterion 1) or 30 % reduction of IOP (criterion 2) with or without hypotensive medications. Persistent hypotony (IOP <5 mmHg after 3 months of follow-up), loss of light perception, and reintervention for IOP control were defined as failure. Mean preoperative IOP and mean IOPs at 12 and 30 months were 27.55 ± 1.16 mmHg (n = 58), 14.45 ± 0.83 mmHg (n = 42), and 14.81 ± 0.87 mmHg (n = 16), respectively. The mean numbers of glaucoma medications preoperatively at 12 and 30 months were 3.17 ± 0.16 (n = 58), 1.81 ± 0.2 (n = 42), and 1.83 ± 0.35 (n = 18), respectively. The reductions in mean IOP and number of medications were statistically significant at all time intervals (P < 0.001). According to criterion 1, Kaplan-Meier survival curves disclosed success rates of 62.9 % at 12 months and 56.6 % at 30 months. According to criterion 2, Kaplan-Meier survival curves disclosed success rates of 43.9 % at 12 months and 32.9 % at 30 months. The most frequent early complication was hypertensive phase (10.3 %) and the most frequent late complication was corneal edema (17.2 %). Second AGV implantation may effectively reduce IOP in eyes with uncontrolled glaucoma, and is associated with relatively few complications.

  12. Check valve with poppet damping mechanism

    NASA Technical Reports Server (NTRS)

    Morris, Brian G. (Inventor)

    1993-01-01

    An inline check valve for a flow line is presented where the valve element is guided for inline travel forward and rearward of a valve sealing member and is spring biased to a closed sealing condition. One of the guides for the valve element includes a dashpot bore and plunger member to control the rate of travel of the valve element in either direction as well as provided a guiding function. The dashpot is not anchored to the valve body so that the valve can be functional even if the plunger member becomes jammed in the dashpot.

  13. Quartz ball valve

    NASA Technical Reports Server (NTRS)

    Goetz, C.; Ingle, W. M. (Inventor)

    1980-01-01

    A ball valve particularly suited for use in the handling of highly corrosive fluids is described. It is characterized by a valve housing formed of communicating segments of quartz tubing, a pair of communicating sockets disposed in coaxial alignment with selected segments of tubing for establishing a pair of inlet ports communicating with a common outlet port, a ball formed of quartz material supported for displacement between the sockets and configured to be received alternately thereby, and a valve actuator including a rod attached to the ball for selectively displacing the ball relative to each of the sockets for controlling fluid flow through the inlet ports.

  14. 47 CFR 87.395 - Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... and Air Navigation Aids (Short Title: SCATANA). 87.395 Section 87.395 Telecommunication FEDERAL... Communications § 87.395 Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA). (a) The Plan for the Security Control of Air Traffic and Air Navigation Aids (SCATANA)...

  15. 47 CFR 87.395 - Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... and Air Navigation Aids (Short Title: SCATANA). 87.395 Section 87.395 Telecommunication FEDERAL... Communications § 87.395 Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA). (a) The Plan for the Security Control of Air Traffic and Air Navigation Aids (SCATANA)...

  16. 47 CFR 87.395 - Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... and Air Navigation Aids (Short Title: SCATANA). 87.395 Section 87.395 Telecommunication FEDERAL... Communications § 87.395 Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA). (a) The Plan for the Security Control of Air Traffic and Air Navigation Aids (SCATANA)...

  17. 47 CFR 87.395 - Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... and Air Navigation Aids (Short Title: SCATANA). 87.395 Section 87.395 Telecommunication FEDERAL... Communications § 87.395 Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA). (a) The Plan for the Security Control of Air Traffic and Air Navigation Aids (SCATANA)...

  18. 47 CFR 87.395 - Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... and Air Navigation Aids (Short Title: SCATANA). 87.395 Section 87.395 Telecommunication FEDERAL... Communications § 87.395 Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA). (a) The Plan for the Security Control of Air Traffic and Air Navigation Aids (SCATANA)...

  19. Essential role of Sox9 in the pathway that controls formation of cardiac valves and septa

    PubMed Central

    Akiyama, Haruhiko; Chaboissier, Marie-Christine; Behringer, Richard R.; Rowitch, David H.; Schedl, Andreas; Epstein, Jonathan A.; de Crombrugghe, Benoit

    2004-01-01

    Epithelial–mesenchymal transformation is a critical developmental process reiterated in multiple organs throughout embryogenesis. Formation of endocardial cushions, primordia of valves and septa, is a classic example of epithelial–mesenchymal transformation. Several gene mutations are known to affect cardiac valve formation. Sox9 is activated when endocardial endothelial cells undergo mesenchymal transformation and migrate into an extracellular matrix, called cardiac jelly, to form endocardial cushions. In Sox9-null mutants, endocardial cushions are markedly hypoplastic. In these mutants, Nfatc1 is ectopically expressed and no longer restricted to endothelial cells. Further, Sox9-deficient endocardial mesenchymal cells fail to express ErbB3, which is required for endocardial cushion cell differentiation and proliferation. Our results reveal a succession of molecular steps in the pathway of endocardial cushion development. We propose that loss of Sox9 inhibits epithelial–mesenchymal transformation after delamination and initial migration, but before definitive mesenchymal transformation. PMID:15096597

  20. Dual Check Valve and Method of Controlling Flow Through the Same

    NASA Technical Reports Server (NTRS)

    Corallo, Roger (Inventor)

    2016-01-01

    A dual check valve includes, a housing having a cavity fluidically connecting three ports, a movable member movably engaged within the cavity from at least a first position occluding a first port of the three ports, a second position occluding a second port of the three ports, and a third position allowing flow between both the first port, the second port and a third port of the three ports.

  1. Achieving indoor air quality through contaminant control

    SciTech Connect

    Katzel, J.

    1995-07-10

    Federal laws outlining industry`s responsibilities in creating a healthy, hazard-free workspace are well known. OSHA`s laws on interior air pollution establish threshold limit values (TLVs) and permissible exposure limits (PELs) for more than 500 potentially hazardous substances found in manufacturing operations. Until now, OSHA has promulgated regulations only for the manufacturing environment. However, its recently-proposed indoor air quality (IAQ) ruling, if implemented, will apply to all workspaces. It regulates IAQ, including environmental tobacco smoke, and requires employers to write and implement IAQ compliance plans.

  2. Fast closing valve

    DOEpatents

    Hanson, Clark L.

    1984-01-10

    A valve is provided for protecting the high vacuum of a particle accelera in the event of air leakage, wherein the valve provides an axially symmetrical passage to avoid disturbance of the partical beam during normal operation, and yet enables very rapid and tight closure of the beam-carrying pipe in the event of air leakage. The valve includes a ball member (30) which can rotate between a first position wherein a bore (32) in the member is aligned with the beam pipe, and a second position out of line with the pipe. A seal member (38) is flexibly sealed to the pipe, and has a seal end which can move tightly against the ball member after the bore has rotated out of line with the pipe, to thereby assure that the seal member does not retard rapid rotation of the ball valve member. The ball valve member can be rapidly rotated by a conductive arm (40) fixed to it and which is rotated by the discharge of a capacitor bank through coils (44, 45) located adjacent to the arm.

  3. AIR DISTRIBUTION NOISE CONTROL IN CRITICAL AUDITORIUMS.

    ERIC Educational Resources Information Center

    HOOVER, R.M.

    THE ACHIEVEMENT OF EXTREMELY LOW AIR-CONDITIONING NOISE LEVELS REQUIRED FOR MODERN AUDITORIUMS ARE THE RESULT OF CAREFUL PLANNING AND THOROUGH DETAILING. PROBLEMS FACED AND TECHNIQUES USED IN ARRIVING AT LEVELS AS LOW AS NC-15 FOR A SINGLE SYSTEM SERVING A HALL ARE DESCRIBED. SIX CASE HISTORIES ARE EXAMINED AND THE FOLLOWING OBSERVATIONS ARE…

  4. Control of Air Leakage in Buildings.

    ERIC Educational Resources Information Center

    Wilson, A. Grant

    This discussion of air leakage emphasizes cause and provides suggestions for elimination of undesirable effects. Cause parameters described are--(1) pressure differential, (2) building shape, (3) temperature differential, (4) opening sizes, (5) mechanical system pressures, and (6) climatic factors. Effects discussed are--(1) increased mechanical…

  5. Terminal area air traffic control simulation

    NASA Technical Reports Server (NTRS)

    1977-01-01

    To study the impact of advanced aeronautical technologies on operations to and from terminal airports, a computer model of air traffic movements was developed. The advantages of fast-time simulation are discussed, and the arrival scheduling and flight simulation are described. A New York area study, user's guide, and programmer's guide are included.

  6. 49 CFR 179.400-19 - Valves and gages.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Valves and gages. 179.400-19 Section 179.400-19... Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.400-19 Valves and gages. (a) Valves. Manually operated shut-off valves and control valves must be provided wherever needed...

  7. Acoustic monitoring of power-plant valves

    NASA Astrophysics Data System (ADS)

    Allen, J. W.; Hartman, W. F.; Robinson, J. C.

    1982-06-01

    Advanced surveillance diagnostics were applied to key nuclear power plant valves to improve the availability of the power plant. Two types of valves were monitored: BWR three-stage, pilot-operated safety/relief valves and PWR feedwater control valves. Excessive leakage across the pilot-disc seat in BWR safety/relief valves can cause the second-stage pressure to reach the critical value that activates the valve, even though the set pressure was not exceeded. Acoustic emissions created by the leak noise were monitored and calibrated to indicate incipient activation of the safety/relief valve. Hydrodynamic, vibration, control and process signals from PWR feedwater control valves were monitored by a mini-computer based surveillance system. On-line analysis of these signals coupled with earlier analytic modelling identified: (1) cavitation, (2) changes in steam packaging tightness, (3) valve stem torquing, (4) transducer oscillations, and (5) peak vibration levels during power transients.

  8. Effect of Mach number, valve angle and length to diameter ratio on thermal performance in flow of air through Ranque Hilsch vortex tube

    NASA Astrophysics Data System (ADS)

    Devade, Kiran D.; Pise, Ashok T.

    2016-04-01

    Ranque Hilsch vortex tube is a device that can produce cold and hot air streams simultaneously from pressurized air. Performance of vortex tube is influenced by a number of geometrical and operational parameters. In this study parametric analysis of vortex tube is carried out. Air is used as the working fluid and geometrical parameters like length to diameter ratio (15, 16, 17, 18), exit valve angles (30°-90°), orifice diameters (5, 6 and 7 mm), 2 entry nozzles and tube divergence angle 4° is used for experimentation. Operational parameters like pressure (200-600 kPa), cold mass fraction (0-1) is varied and effect of Mach number at the inlet of the tube is investigated. The vortex tube is tested at sub sonic (0 < Ma < 1), sonic (Ma = 1) and supersonic (1 < Ma < 2) Mach number, and its effect on thermal performance is analysed. As a result it is observed that, higher COP and low cold end temperature is obtained at subsonic Ma. As CMF increases, COP rises and cold and temperature drops. Optimum performance of the tube is observed for CMF up to 0.5. Experimental correlations are proposed for optimum COP. Parametric correlation is developed for geometrical and operational parameters.

  9. Design of a cyclic pressure bioreactor for the ex vivo study of aortic heart valves.

    PubMed

    Schipke, Kimberly J; To, S D Filip; Warnock, James N

    2011-01-01

    air into the system at the appropriate rate. The system mimicked the dynamic transvalvular pressure levels associated with the aortic valve; a saw tooth wave produced a gradual increase in pressure, typical of the transvalvular pressure gradient that is present across the valve during diastole, followed by a sharp pressure drop depicting valve opening in systole. The LabVIEW program allowed users to control the magnitude and frequency of cyclic pressure. The system was able to subject tissue samples to physiological and pathological pressure conditions. This device can be used to increase our understanding of how heart valves respond to changes in the local mechanical environment. PMID:21876532

  10. Piston reciprocating compressed air engine

    SciTech Connect

    Cestero, L.G.

    1987-03-24

    A compressed air engine is described comprising: (a). a reservoir of compressed air, (b). two power cylinders each containing a reciprocating piston connected to a crankshaft and flywheel, (c). a transfer cylinder which communicates with each power cylinder and the reservoir, and contains a reciprocating piston connected to the crankshaft, (d). valve means controlled by rotation of the crankshaft for supplying compressed air from the reservoir to each power cylinder and for exhausting compressed air from each power cylinder to the transfer cylinder, (e). valve means controlled by rotation of the crankshaft for supplying from the transfer cylinder to the reservoir compressed air supplied to the transfer cylinder on the exhaust strokes of the pistons of the power cylinders, and (f). an externally powered fan for assisting the exhaust of compressed air from each power cylinder to the transfer cylinder and from there to the compressed air reservoir.

  11. Realization of the Atkinson-Miller cycle in spark-ignition engine by means of the fully variable inlet valve control system

    NASA Astrophysics Data System (ADS)

    Żmudka, Zbigniew; Postrzednik, Stefan; Przybyła, Grzegorz

    2014-09-01

    The theoretical analysis of the charge exchange process in a spark ignition engine has been presented. This process has significant impact on the effectiveness of engine operation because it is related to the necessity of overcoming the flow resistance, followed by the necessity of doing a work, so-called the charge exchange work. The flow resistance caused by the throttling valve is especially high during the part load operation. The open Atkinson-Miller cycle has been assumed as a model of processes taking place in the engine. Using fully variable inlet valve timing the A-M cycle can be realized according to two systems: system with late inlet valve closing and system with early inlet valve closing. The systems have been analysed individually and comparatively with the open Seiliger-Sabathe cycle which is a theoretical cycle for the classical throttle governing of the engine load. Benefits resulting from application of the systems with independent inlet valve control have been assessed on the basis of the selected parameters: fuel dose, cycle work, charge exchange work and a cycle efficiency. The use of the analysed systems to governing of the SI engine load will enable to eliminate a throttling valve from the system inlet and reduce the charge exchange work, especially within the range of part load operation.

  12. Two stroke engine with deflector valve

    SciTech Connect

    Weiland, C.

    1987-06-09

    The patent describes two stroke internal combustion engine comprising cylinder with cylinder head closure at one end, piston with crankshaft driven means for reciprocating within the cylinder to compress a fuel air mixture during its compression stroke and to deliver power upon ignition during its power stroke; a plurality of circumferentially spaced exhaust ports in the wall of the cylinder uncovered by the piston near the end of its power stroke, port means in the cylinder head closure with valve means for controlling port communication with the cylinder, compressor means for delivering supercharged air to one of the port means.

  13. Innovative Air Conditioning and Climate Control

    NASA Technical Reports Server (NTRS)

    Graf, John

    2015-01-01

    NASA needed to develop a desiccant wheel based humidity removal system to enable the long term testing of the Orion CO2 scrubber on the International Space Station. In the course of developing that system, we learned three things that are relevant to energy efficient air conditioning of office towers. NASA developed a conceptual design for a humidity removal system for an office tower environment. We are looking for interested partners to prototype and field test this concept.

  14. Vehicle height and posture control of the electronic air suspension system using the hybrid system approach

    NASA Astrophysics Data System (ADS)

    Sun, Xiaoqiang; Cai, Yingfeng; Chen, Long; Liu, Yanling; Wang, Shaohua

    2016-03-01

    The electronic air suspension (EAS) system can improve ride comfort, fuel economy and handling safety of vehicles by adjusting vehicle height. This paper describes the development of a novel controller using the hybrid system approach to adjust the vehicle height (height control) and to regulate the roll and pitch angles of the vehicle body during the height adjustment process (posture control). The vehicle height adjustment system of EAS poses challenging hybrid control problems, since it features different discrete modes of operation, where each mode has an associated linear continuous-time dynamic. In this paper, we propose a novel approach to the modelling and controller design problem for the vehicle height adjustment system of EAS. The system model is described firstly in the hybrid system description language (HYSDEL) to obtain a mixed logical dynamical (MLD) hybrid model. For the resulting model, a hybrid model predictive controller is tuned to improve the vehicle height and posture tracking accuracy and to achieve the on-off statuses direct control of solenoid valves. The effectiveness and performance of the proposed approach are demonstrated by simulations and actual vehicle tests.

  15. Giant tunneling electroresistance effect driven by an electrically controlled spin valve at a complex oxide interface.

    PubMed

    Burton, J D; Tsymbal, E Y

    2011-04-15

    A giant tunneling electroresistance effect may be achieved in a ferroelectric tunnel junction by exploiting the magnetoelectric effect at the interface between the ferroelectric barrier and a magnetic La(1-x)Sr(x)MnO3 electrode. Using first-principles density-functional theory we demonstrate that a few magnetic monolayers of La(1-x)Sr(x)MnO3 near the interface act, in response to ferroelectric polarization reversal, as an atomic-scale spin valve by filtering spin-dependent current. This produces more than an order of magnitude change in conductance, and thus constitutes a giant resistive switching effect. PMID:21568608

  16. Dedicated EGR engine with dynamic load control

    DOEpatents

    Hayman, Alan W.; McAlpine, Robert S.; Keating, Edward J.

    2016-09-06

    An internal combustion engine comprises a first engine bank and a second engine bank. A first intake valve is disposed in an intake port of a cylinder of the first engine bank, and is configured for metering the first flow of combustion air by periodically opening and closing according to a first intake valve lift and duration characteristic. A variable valve train control mechanism is configured for affecting the first intake valve lift and duration characteristic. Either a lift or duration of the first intake valve is modulated so as to satisfy an EGR control criterion.

  17. Power plant air pollutant control 'Mega' symposium

    SciTech Connect

    2008-07-01

    Topics covered carbon management technologies, mercury (FGD-based controls, sorbents, TOXECON, additives and SO{sub 3} countermeasures 0, NOx (combined controls, SCR), SO{sub 2}, SO{sub 3}, multi-pollutant controls, particulates, and coal combustion products. The poster papers are also included.

  18. VERIFICATION TESTING OF AIR POLLUTION CONTROL TECHNOLOGY QUALITY MANAGEMENT PLAN

    EPA Science Inventory

    This document is the basis for quality assurance for the Air Pollution Control Technology Verification Center (APCT Center) operated under the U.S. Environmental Protection Agency (EPA). It describes the policies, organizational structure, responsibilities, procedures, and qualit...

  19. 24. DETAIL ELEVATION OF SECOND FLOOR AIR TRAFFIC CONTROL CENTER ...

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

    24. DETAIL ELEVATION OF SECOND FLOOR AIR TRAFFIC CONTROL CEN-TER DOOR. - Newark International Airport, Administration Building, Brewster Road between Route 21 & New Jersey Turnpike Exchange No. 14, Newark, Essex County, NJ

  20. 7. Northeast view interior, air traffic control and landing system ...

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

    7. Northeast view interior, air traffic control and landing system room 25 - Selfridge Field, Building No. 1050, Northwest corner of Doolittle Avenue & D Street; Harrison Township, Mount Clemens, Macomb County, MI

  1. 76 FR 39357 - Revisions to the California State Implementation Plan, Imperial County Air Pollution Control...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-06

    ... Pollution Control District, Kern County Air Pollution Control District, and Ventura County Air Pollution... proposing to approve revisions to the Imperial County Air Pollution Control District (ICAPCD), Kern County Air Pollution Control District (KCAPCD), and Ventura County Air Pollution Control District...

  2. Quantification and control of the spatiotemporal gradients of air speed and air temperature in an incubator.

    PubMed

    Van Brecht, A; Aerts, J M; Degraeve, P; Berckmans, D

    2003-11-01

    Around the optimal incubator air temperature only small spatiotemporal deviations are allowed. However, air speed and air temperature are not uniformly distributed in the total volume of the incubator due to obstruction of the eggs and egg trays. The objectives of this research were (1) to quantify the spatiotemporal gradients in temperature and velocity and (2) to develop and validate a control algorithm to increase the uniformity in temperature during the entire incubation process. To improve the uniformity of air temperature, the airflow pattern and the air quality need to be controlled more optimally. These data show that the air temperature between the eggs at a certain position in a large incubator is the result of (1) the mean air temperature of the incubator; (2) the exchange of heat between the egg and its micro-environment, which is affected by the air speed at that certain position; (3) the time-variable heat production of the embryo; and (4) the heat influx or efflux as a result from the movement of hot or cold air in the incubator toward that position, which is affected by the airflow pattern. This implies that the airflow pattern needs to be controlled in a more optimal way. To maximize the uniformity of air temperature, an active and adaptive control of the three-dimensional (3-D) airflow pattern has been developed and tested. It was found to improve the spatiotemporal temperature distribution. The chance of having a temperature reading in the interval from 37.5 to 38.1 degrees C increased by 3% compared to normal operating conditions.

  3. Depressurization valve

    DOEpatents

    Skoda, George I.

    1989-01-01

    A depressurization valve for use in relieving completely the pressure in a simplified boiling water reactor is disclosed. The normally closed and sealed valve is provided with a valve body defining a conduit from an outlet of a manifold from the reactor through a valve seat. A closing valve disk is configured for fitting to the valve seat to normally close the valve. The seat below the disk is provided with a radially extending annulus extending a short distance into the aperture defined by the seat. The disk is correspondingly provided with a longitudinally extending annulus that extends downwardly through the aperture defined by the seat towards the high pressure side of the valve body. A ring shaped membrane is endlessly welded to the seat annulus and to the disk annulus. The membrane is conformed over the confronted surface of the seat and disk in a C-sectioned configuration to seal the depressurization valve against the possibility of weeping. The disk is held to the closed position by an elongate stem extending away from the high pressure side of the valve body. The stem has a flange configured integrally to the stem for bias by two springs. The first spring acts from a portion of the housing overlying the disk on the stem flange adjacent the disk. This spring urges the stem and attached disk away from the seat and thus will cause the valve to open at any pressure. A second spring--preferably of the Belleville variety--acts on a latch plate surrounding and freely moving relative to the end of the stem. This second spring overcomes the bias of the first spring and any pressure acting upon the disk. This Belleville spring maintains through its spring force the valve in the closed position. At the same time, the latch plate with its freedom of movement relative to the stem allows the stem to thermally expand during valve temperature excursion. The latch plate in surrounding the stem is limited in its outward movement by a boss attached to the stem at the end of

  4. Speed control with end cushion for high speed air cylinder

    DOEpatents

    Stevens, Wayne W.; Solbrig, Charles W.

    1991-01-01

    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.

  5. Safety Testing of Left Ventricular Vent Valves.

    PubMed

    Gavin, Caroline; Coblentz, John; Acsell, Jeffrey R; Shackelford, Anthony G; Sistino, Joseph J

    2015-03-01

    Vent vacuum relief valves (VRVs) are used to limit the negative pressure at the ventricular vent catheter tip as well as prevent reversal of blood flow and prevention of air embolism. The purpose of this study was to evaluate the performance of three commercially available ventricular vent valves. The negative pressure at which the vent valve opened was measured at the valve inlet using high-fidelity pressure transducers. Also, the flow rate at which air entrainment occurred due to valve opening was recorded. Using a 51.5 cm column of saline, the resistance for each valve was calculated. The mean ± SD opening negative pressures were -231.3 ± 35.2 mmHg for the Quest Medical valve, -219.8 mmHg ± 17.2 for the Sorin valve, and -329.6 · 38.0 mmHg for the Terumo valve. The red Quest Medical valve opened at a lower flow (1.44 ± .03 L/min) than the dark blue Sorin valve (2.93 ± .01 L/min) and light blue LH130 Terumo valve (2.36 ± .02 L/min). The Sorin valve had the least resistance of 34.1 dyn-s/cm, followed by the Terumo LH130 valve resistance of 58.1 dyn·s/cm5, and the Quest Medical VRV-II valve with a resistance of 66.5 dyn·s/cm. We found that the valves are significantly different in the negative pressure generated. Understanding the limitations of these devices is important to reduce the occurrence of adverse events associated with venting and to select the best device for a specific clinical application.

  6. Control of asthma triggers in indoor air with air cleaners: a modeling analysis

    PubMed Central

    Myatt, Theodore A; Minegishi, Taeko; Allen, Joseph G; MacIntosh, David L

    2008-01-01

    Background Reducing exposure to environmental agents indoors shown to increase asthma symptoms or lead to asthma exacerbations is an important component of a strategy to manage asthma for individuals. Numerous investigations have demonstrated that portable air cleaning devices can reduce concentrations of asthma triggers in indoor air; however, their benefits for breathing problems have not always been reproducible. The potential exposure benefits of whole house high efficiency in-duct air cleaners for sensitive subpopulations have yet to be evaluated. Methods We used an indoor air quality modeling system (CONTAM) developed by NIST to examine peak and time-integrated concentrations of common asthma triggers present in indoor air over a year as a function of natural ventilation, portable air cleaners, and forced air ventilation equipped with conventional and high efficiency filtration systems. Emission rates for asthma triggers were based on experimental studies published in the scientific literature. Results Forced air systems with high efficiency filtration were found to provide the best control of asthma triggers: 30–55% lower cat allergen levels, 90–99% lower risk of respiratory infection through the inhalation route of exposure, 90–98% lower environmental tobacco smoke (ETS) levels, and 50–75% lower fungal spore levels than the other ventilation/filtration systems considered. These results indicate that the use of high efficiency in-duct air cleaners provide an effective means of controlling allergen levels not only in a single room, like a portable air cleaner, but the whole house. Conclusion These findings are useful for evaluating potential benefits of high efficiency in-duct filtration systems for controlling exposure to asthma triggers indoors and for the design of trials of environmental interventions intended to evaluate their utility in practice. PMID:18684328

  7. Packing developments improve valve availability

    SciTech Connect

    Aikin, J.

    1994-01-01

    Regulatory environment and clean air legislation demand improvements in valve stuffing box performance. In normally inaccessible or hazardous areas, the cost of valve maintenance and repair in terms of safety, radiation, and toxic gas exposure is very high. AECL Research`s Mechanical Equipment Development (MED) branch at Chalk River Laboratories (Chalk River, Ont.) has researched stem packing leakage problems since the early 1970s. Early research and development (R and D) significantly improved the understanding of operational characteristics of asbestos-based valve packing. Of note was the development of live loading, a stem packing method that reduces valve leakage to near zero under most operating conditions, and significantly prolongs packing life. This article describes how stem packing developments, including live loading techniques, are reducing valve fugitive emissions and leakage.

  8. Large scale steam valve test: Performance testing of large butterfly valves and full scale high flowrate steam testing

    SciTech Connect

    Meadows, J.B.; Robbins, G.E.; Roselius, D.G.

    1995-05-01

    This report presents the results of the design testing of large (36-inch diameter) butterfly valves under high flow conditions. The two butterfly valves were pneumatically operated air-open, air-shut valves (termed valves 1 and 2). These butterfly valves were redesigned to improve their ability to function under high flow conditions. Concern was raised regarding the ability of the butterfly valves to function as required with high flow-induced torque imposed on the valve discs during high steam flow conditions. High flow testing was required to address the flow-induced torque concerns. The valve testing was done using a heavily instrumented piping system. This test program was called the Large Scale Steam Valve Test (LSSVT). The LSSVT program demonstrated that the redesigned valves operated satisfactorily under high flow conditions.

  9. Valve assembly

    SciTech Connect

    Marshala, D.L.

    1986-12-16

    This patent describes a subsurface pump actuated by a reciprocatable sucker rod for producing well liquids from a subsurface reservoir involving a piston adapted to reciprocate within a cylinder immersed in the reservoir, the piston being provided with a traveling valve. The improvement described here comprises valve means connected to the sucker tod for lifting a body of fluid during upstrokes of the sucker rod, the valve means comprising: a barrel assembly having an internal bore and comprising: a lower barrel member; and an upper barrel assembly connected to the lower barrel and having a beveled seating surface with at least one fluid port therethrough.

  10. Nuclear radiation actuated valve

    DOEpatents

    Christiansen, David W.; Schively, Dixon P.

    1985-01-01

    A nuclear radiation actuated valve for a nuclear reactor. The valve has a valve first part (such as a valve rod with piston) and a valve second part (such as a valve tube surrounding the valve rod, with the valve tube having side slots surrounding the piston). Both valve parts have known nuclear radiation swelling characteristics. The valve's first part is positioned to receive nuclear radiation from the nuclear reactor's fuel region. The valve's second part is positioned so that its nuclear radiation induced swelling is different from that of the valve's first part. The valve's second part also is positioned so that the valve's first and second parts create a valve orifice which changes in size due to the different nuclear radiation caused swelling of the valve's first part compared to the valve's second part. The valve may be used in a nuclear reactor's core coolant system.

  11. 75 FR 56889 - Revisions to the California State Implementation Plan, San Diego County Air Pollution Control...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-17

    ...: EPA is taking direct final action to approve revisions to the San Diego County Air Pollution Control... Environmental protection, Air pollution control, Incorporation by reference, Intergovernmental relations.... * * * * * (c) * * * (379) * * * (i) * * * (B) San Diego County Air Pollution Control District. (1) Rule...

  12. 40 CFR 81.77 - Puerto Rico Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 18 2012-07-01 2012-07-01 false Puerto Rico Air Quality Control Region... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.77 Puerto Rico Air Quality Control Region. The Puerto Rico Air Quality Control...

  13. 40 CFR 81.77 - Puerto Rico Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Puerto Rico Air Quality Control Region... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.77 Puerto Rico Air Quality Control Region. The Puerto Rico Air Quality Control...

  14. 40 CFR 81.77 - Puerto Rico Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 18 2013-07-01 2013-07-01 false Puerto Rico Air Quality Control Region... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.77 Puerto Rico Air Quality Control Region. The Puerto Rico Air Quality Control...

  15. 76 FR 39303 - Revisions to the California State Implementation Plan, Imperial County Air Pollution Control...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-06

    ... Pollution Control District, Kern County Air Pollution Control District, and Ventura County Air Pollution... taking direct final action to approve revisions to the Imperial County Air Pollution Control District (ICAPCD), Kern County Air Pollution Control District (KCAPCD), and Ventura County Air Pollution...

  16. Control of indoor air contaminants. Progress report

    SciTech Connect

    Ayer, H.E.

    1988-01-01

    Efforts were made to determine the probability of air contaminants within 1 meter reaching the nose from either a point-source thermal generation of an aerosol or from generations of vapor by evaporation. The study also attempted to define the objective criteria for evaluation of mixing (K) factors between 1 and 10 meters of individual contaminant spaces or in an entire room. Small, thermally generated plumes were able to move with little dilution through spaces of 1 meter and more. Concentrations of acrolein and formaldehyde in side-stream cigarette smoke were tens to hundreds of times the acceptable limits. Between one and two thirds of these concentrations were associated with the particulate phase of the smoke, suggesting that aldehydes may be deposited in the respiratory system rather than absorbed in the nose and trachea, perhaps providing a pathway for bronchial cancer. Concentrations of irritants in contaminant streams sufficient to cause eye or nose/throat irritation may be measured by sampling close enough to the source to trap the entire contaminant stream.

  17. Training augmentation device for the Air Force satellite Control Network

    NASA Technical Reports Server (NTRS)

    Shoates, Keith B.

    1993-01-01

    From the 1960's and into the early 1980's satellite operations and control were conducted by Air Force Systems Command (AFSC), now Air Force Materiel Command (AFMC), out of the Satellite Control Facility at Onizuka AFB, CA. AFSC was responsible for acquiring satellite command and control systems and conducting routine satellite operations. The daily operations, consisting of satellite health and status contacts and station keeping activities, were performed for AFSC by a Mission Control Team (MCT) staffed by civilian contractors who were responsible for providing their own technically 'qualified' personnel as satellite operators. An MCT consists of five positions: mission planner, ground controller, planner analyst, orbit analyst, and ranger controller. Most of the training consisted of On-the-Job-Training (OJT) with junior personnel apprenticed to senior personnel until they could demonstrate job proficiency. With most of the satellite operators having 15 to 25 years of experience, there was minimal risk to the mission. In the mid 1980's Air Force Space Command (AFSPACOM) assumed operational responsibility for a newly established control node at Falcon AFB (FAFB) in CO. The satellites and ground system program offices (SPO's) are organized under AFSC's Space and Missiles Systems Center (SMC) to function as a systems engineering and acquisition agency for AFSPACECOM. The collection of the satellite control nodes, ground tracking stations, computer processing equipment, and connecting communications links is referred to as the Air Force Satellite Control Network (AFSCN).

  18. Acoustic monitoring of power plant valves

    NASA Astrophysics Data System (ADS)

    Allen, J. W.; Hartman, W. F.; Robinson, J. C.

    1982-06-01

    Advanced surveillance diagnostics were applied to key nuclear power plant valves to improve the availability of the power plant. Two types of valves were monitored: boiling water reactor (BWR) three-stage, pilot-operated safety/relief valves and pressurized water reactor (PWR) feedwater control valves. Excessive leakage across the pilot-disc seat in BWR safety/relief valves can cause the second-stage pressure to reach the critical value that activates the valve, even though the set pressure was not exceeded. Acoustic emission created by the leak noise were monitored and calibrated to indicate incipient activation of the safety/relief valve. Hydrodynamic, vibration, control and process signals frm PWR feedwater control valves were monitored by a mini-computer based surveillance system.

  19. Josephson magnetic rotary valve

    SciTech Connect

    Soloviev, I. I.; Klenov, N. V.; Bakurskiy, S. V.; Bol'ginov, V. V.; Ryazanov, V. V.; Kupriyanov, M. Yu.; Golubov, A. A.

    2014-12-15

    We propose a control element for a Josephson spin valve. It is a complex Josephson device containing ferromagnetic (F) layer in the weak-link area consisting of two regions, representing 0 and π Josephson junctions, respectively. The valve's state is defined by mutual orientations of the F-layer magnetization vector and boundary line between 0 and π sections of the device. We consider possible implementation of the control element by introduction of a thin normal metal layer in a part of the device area. By means of theoretical simulations, we study properties of the valve's structure as well as its operation, revealing such advantages as simplicity of control, high characteristic frequency, and good legibility of the basic states.

  20. Voice data entry in air traffic control

    NASA Technical Reports Server (NTRS)

    Connolly, Donald W.

    1977-01-01

    Several of the keyboard data languages were tabulated and analyzed. The key language chosen as a test vehicle was that used by the nonradar or flight data controllers. This application was undertaken to minimize effort in a cost efficient way and with less research and development.

  1. Implications of Using Different Methods to Characterise Anticoagulant Control in Patients with Second Generation Mechanical Heart Valve Prostheses

    PubMed Central

    Fiorentino, Francesca; Rogers, Chris A.; Bryan, Alan J.; Angelini, Gianni D.; Reeves, Barnaby C.

    2014-01-01

    Objective Characterisation of anticoagulant control is fundamental to investigations of its association with clinical outcome. Anticoagulant control depends on several factors. This paper aims to illustrate the implications of different methods for measuring and analysing anticoagulant control in patients with second generation mechanical heart valve prostheses. Methods International normalised ratio (INR) data collected during the 10-year follow-up of a randomised controlled trial were analysed. We considered the influence of: 3 different target INR ranges; anticoagulant control expressed as the proportion of INR readings (PoR) vs. anticoagulant control follow-up time (PoT); 3 ways of describing the profile of anticoagulant control over time. Results Different target INR ranges dramatically influenced derived measures of anticoagulant control; the PoT within the target range varied from 88% for the widest to 28% for narrowest range. Overall distributions of PoR and PoT observations were similar but differed by up to ±20% for individuals; PoT exceeded PoR when control was good but was less than PoR when control was poor. Classifying PoT outside the target range showed that widely varying combinations of PoT too high and too low are possible across individuals. Conclusions Researchers' choices about methods for measuring and quantifying anticoagulant control markedly influence the values derived from INR readings. The use of different methods across studies makes it difficult or impossible to compare findings and to establish an evidence base for clinical practice. Methods for quantifying anticoagulant control should be standardised. PMID:24988447

  2. Spin valves based on Mn{sub 75}Ir{sub 25} antiferromagnet with controllable functional parameters

    SciTech Connect

    Milyaev, M. A. Naumova, L. I.; Kamenskii, I. Yu.; Ustinov, V. V.

    2015-12-15

    Using the example of spin valves of the Ta(50 Å)/Ni{sub 80}Fe{sub 20}(30 Å)/Co{sub 90}Fe{sub 10}(15 Å)/Cu(28 Å)/Co{sub 90}Fe{sub 10}(20 Å)/Mn{sub 75}Ir{sub 25}(50 Å)/Ta(20 Å) composition, factors controlling the hysteresis properties are studied for the case of macro- and microscopic sizes of an experimental sample. It is shown that a linear change in the magnetoresistance with small hysteresis while retaining the giant magnetoresistance effect at a level of 8% can be obtained in a micro-object (meander) using thermomagnetic treatment.

  3. Cognitive Task Analysis of Prioritization in Air Traffic Control.

    ERIC Educational Resources Information Center

    Redding, Richard E.; And Others

    A cognitive task analysis was performed to analyze the key cognitive components of the en route air traffic controllers' jobs. The goals were to ascertain expert mental models and decision-making strategies and to identify important differences in controller knowledge, skills, and mental models as a function of expertise. Four groups of…

  4. Design and analysis of a gyroscopically controlled micro air vehicle

    NASA Astrophysics Data System (ADS)

    Thorne, Christopher Everett

    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.

  5. Anxiety, locus of control and appraisal of air pollution

    SciTech Connect

    Navarro, P.L.; Simpson-Housley, P.; de Man, A.F.

    1987-06-01

    100 residents of Santiago de Chile took part in a study of the relationship among locus of control, trait-anxiety, and perception of air pollution. Concern over the problem of atmospheric pollution and number of antipollution measures taken was related to trait-anxiety. Locus of control was associated with variation in awareness of pollution hazard.

  6. Process Heater Ultra-low Excess Air Control

    SciTech Connect

    David V. Thompson

    2006-06-30

    The objective of this project was to demonstrate automatic control of combustion within process heaters using flue gas carbon monoxide (CO) instead of flue gas oxygen (excess air) as the control point for the burner registers to continually achieve near stoichiometric conditions without operator adjustments.

  7. Development of an effective valve packing program

    SciTech Connect

    Hart, K.A.

    1996-12-01

    Current data now shows that graphite valve packing installed within the guidance of a controlled program produces not only reliable stem sealing but predictable running loads. By utilizing recent technological developments in valve performance monitoring for both MOV`s and AOV`s, valve packing performance can be enhanced while reducing maintenance costs. Once known, values are established for acceptable valve packing loads, the measurement of actual valve running loads via the current MOV/AOV diagnostic techniques can provide indication of future valve stem sealing problems, improper valve packing installation or identify the opportunity for valve packing program improvements. At times the full benefit of these advances in material and predictive technology remain under utilized due to simple past misconceptions associated with valve packing. This paper will explore the basis for these misconceptions, provide general insight into the current understanding of valve packing and demonstrate how with this new understanding and current valve diagnostic equipment the key aspects required to develop an effective, quality valve packing program fit together. The cost and operational benefits provided by this approach can be significant impact by the: elimination of periodic valve repacking, reduction of maintenance costs, benefits of leak-free valve operation, justification for reduced Post Maintenance Test Requirements, reduced radiation exposure, improved plant appearance.

  8. 21. Interior view of citric acid air pollution control room ...

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

    21. Interior view of citric acid air pollution control room (also known as scrubber room) in Components Test Laboratory (T-27), looking southeast. Photograph shows upgraded instrumentation, piping, tanks, and technological modifications installed in 1997-99 to accommodate component testing requirements for the Atlas V missile. - Air Force Plant PJKS, Systems Integration Laboratory, Components Test Laboratory, Waterton Canyon Road & Colorado Highway 121, Lakewood, Jefferson County, CO

  9. A vacuum-driven peristaltic micropump with valved actuation chambers

    NASA Astrophysics Data System (ADS)

    Cui, Jianguo; Pan, Tingrui

    2011-06-01

    This paper presents a simple peristaltic micropump design incorporated with valved actuation chambers and propelled by a pulsed vacuum source. The vacuum-driven peristaltic micropump offers high pumping rates, low backflow, appreciable tolerance to air bubbles, and minimal destruction to fluid contents. The pumping device, fabricated by laser micromachining and plasma bonding of three polydimethylsiloxane (PDMS) layers, includes a pneumatic network, actuation membranes, and microfluidic channels. As the key to peristaltic motion, the sequential deflection of the elastic membranes is achieved by periodic pressure waveforms (negative) traveling through the pneumatic network, provided by a vacuum source regulated by an electromagnetic valve. This configuration eliminates the complicated control logic typically required in peristaltic motion. Importantly, the valved actuation chambers substantially reduce backflow and improve the pumping rates. In addition, the pneumatic network with negative pressure provides a means to effectively remove air bubbles present in the microflow through the gas-permeable PDMS membrane, which can be highly desired in handling complex fluidic samples. Experimental characterization of the micropump performance has been conducted by controlling the resistance of the pneumatic network, the number of normally closed valves, the vacuum pressure, and the frequency of pressure pulses. A maximal flow rate of 600 µL min-1 has been optimized at the pulsed vacuum frequency of 30 Hz with a vacuum pressure of 50 kPa, which is comparable to that of compressed air-actuated peristaltic micropumps.

  10. Air conditioning system and component therefore distributing air flow from opposite directions

    NASA Technical Reports Server (NTRS)

    Obler, H. D.; Bauer, H. B. (Inventor)

    1974-01-01

    The air conditioning system comprises a plurality of separate air conditioning units coupled to a common supply duct such that air may be introduced into the supply duct in two opposite flow directions. A plurality of outlets such as registers or auxiliary or branch ducts communicate with the supply duct and valve means are disposed in the supply duct at at least some of the outlets for automatically channelling a controllable amount of air from the supply duct to the associated outlet regardless of the direction of air flow within the supply duct. The valve means comprises an automatic air volume control apparatus for distribution within the air supply duct into which air may be introduced from two opposite directions. The apparatus incorporates a freely swinging movable vane in the supply duct to automatically channel into the associated outlet only the deflected air flow which has the higher relative pressure.

  11. 40 CFR 81.88 - Billings Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air...: Region II. 481.169Helena Intrastate Air Quality Control Region: Region IV. 481.170Miles City...

  12. 40 CFR 81.88 - Billings Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air...: Region II. 481.169Helena Intrastate Air Quality Control Region: Region IV. 481.170Miles City...

  13. Combination throttle and shutoff valve

    NASA Technical Reports Server (NTRS)

    Carriker, J. W.

    1972-01-01

    Combination of translating sleeve throttle valve and conventional poppet valve provides capability of shutting off flow completely by poppet and sleeve control of the rate of flow. Integration of the two concepts can be accomplished without difficulty and in a manner that requires a minimum of development.

  14. Variable gas leak rate valve

    DOEpatents

    Eernisse, Errol P.; Peterson, Gary D.

    1976-01-01

    A variable gas leak rate valve which utilizes a poled piezoelectric element to control opening and closing of the valve. The gas flow may be around a cylindrical rod with a tubular piezoelectric member encircling the rod for seating thereagainst to block passage of gas and for reopening thereof upon application of suitable electrical fields.

  15. Idling control device for internal combustion engine with turbocharger

    SciTech Connect

    Ando, H.; Kondo, T.

    1986-09-23

    An idling control device is described for an internal combustion engine with a turbocharger, comprising: an air intake pipe having an inlet at an upstream end thereof adapted to accept air which is to be supplied through the air intake pipe to the internal combustion engine a turbocharger having a housing incorporated in the air intake pipe between the inlet and the outlet, a throttle valve incorporated in the air intake pipe between the turbocharger and the outlet, a surge tank incorporated in the air intake pipe between the throttle valve and the outlet; a bypass air passage means provided in parallel with the air intake pipe between upstream of the turbocharger and downstream of the throttle valve; a flow-control valve incorporated in the bypass air passage means; an actuator operatively associated with the flow-control valve, a computer operatively associated with the actuator and arranged to receive signals relating to operating conditions of the engine; a check valve incorporated in the bypass air passage means downstream of the flow-control valve.

  16. 40 CFR 81.59 - Cumberland-Keyser Interstate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.59 Cumberland-Keyser Interstate Air Quality Control Region. The Cumberland-Keyser Interstate Air Quality Control Region (Maryland-West Virginia) has been revised to...

  17. 40 CFR 81.16 - Metropolitan Denver Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.16 Metropolitan Denver Intrastate Air Quality Control Region. The Metropolitan Denver Intrastate Air Quality Control Region (Colorado) consists of the territorial...

  18. 40 CFR 81.43 - Metropolitan Toledo Interstate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.43 Metropolitan Toledo Interstate Air Quality Control Region. The Metropolitan Toledo Interstate Air Quality Control Region (Ohio-Michigan) consists of the territorial...

  19. 40 CFR 81.49 - Southeast Florida Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.49 Southeast Florida Intrastate Air Quality Control Region. The Southeast Florida Intrastate Air Quality Control Region is redesignated to consist of the territorial...

  20. 40 CFR 81.62 - Northeast Mississippi Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.62 Northeast Mississippi Intrastate Air Quality Control Region. The Alabama-Mississippi-Tennessee Interstate Air Quality Control Region has been renamed the...

  1. 40 CFR 81.24 - Niagara Frontier Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.24 Niagara Frontier Intrastate Air Quality Control Region. The Niagara Frontier Intrastate Air Quality Control Region (New York) consists of the territorial...

  2. 40 CFR 81.28 - Metropolitan Baltimore Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.28 Metropolitan Baltimore Intrastate Air Quality Control Region. The Metropolitan Baltimore Intrastate Air Quality Control Region (Maryland) consists of the territorial...

  3. 40 CFR 81.34 - Metropolitan Dayton Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.34 Metropolitan Dayton Intrastate Air Quality Control Region. The Metropolitan Dayton Intrastate Air Quality Control Region consists of the territorial area encompassed by...

  4. 40 CFR 81.47 - Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.47 Central Oklahoma Intrastate Air Quality Control Region. The Metropolitan Oklahoma Intrastate Air Quality Control Region has been renamed the Central Oklahoma...

  5. 40 CFR 81.14 - Metropolitan Chicago Interstate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.14 Metropolitan Chicago Interstate Air Quality Control Region. The Metropolitan Chicago Interstate Air Quality Control Region (Illinois-Indiana) is revised to consist of...

  6. 40 CFR 81.19 - Metropolitan Boston Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.19 Metropolitan Boston Intrastate Air Quality Control Region. The Metropolitan Boston Intrastate Air Quality Control Region (Massachusetts) consists of the territorial...

  7. 40 CFR 81.59 - Cumberland-Keyser Interstate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.59 Cumberland-Keyser Interstate Air Quality Control Region. The Cumberland-Keyser Interstate Air Quality Control Region (Maryland-West Virginia) has been revised to...

  8. 40 CFR 81.75 - Metropolitan Charlotte Interstate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.75 Metropolitan Charlotte Interstate Air Quality Control Region. The Metropolitan Charlotte Interstate Air Quality Control Region (North Carolina-South Carolina) has been...

  9. 40 CFR 81.44 - Metropolitan Memphis Interstate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.44 Metropolitan Memphis Interstate Air Quality Control Region. The Metropolitan Memphis Interstate Air Quality Control Region (Arkansas-Mississippi-Tennessee) consists of...

  10. 40 CFR 81.31 - Metropolitan Providence Interstate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.31 Metropolitan Providence Interstate Air Quality Control Region. The Metropolitan Providence Interstate Air Quality Control Region (Rhode Island-Massachusetts) consists of...

  11. 40 CFR 81.14 - Metropolitan Chicago Interstate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.14 Metropolitan Chicago Interstate Air Quality Control Region. The Metropolitan Chicago Interstate Air Quality Control Region (Illinois-Indiana) is revised to consist of...

  12. 40 CFR 81.30 - Southeastern Wisconsin Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.30 Southeastern Wisconsin Intrastate Air Quality Control Region. The Metropolitan Milwaukee Intrastate Air Quality Control Region (Wisconsin) has been renamed the...

  13. 40 CFR 81.75 - Metropolitan Charlotte Interstate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.75 Metropolitan Charlotte Interstate Air Quality Control Region. The Metropolitan Charlotte Interstate Air Quality Control Region (North Carolina-South Carolina) has been...

  14. 40 CFR 81.24 - Niagara Frontier Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.24 Niagara Frontier Intrastate Air Quality Control Region. The Niagara Frontier Intrastate Air Quality Control Region (New York) consists of the territorial...

  15. 40 CFR 81.34 - Metropolitan Dayton Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.34 Metropolitan Dayton Intrastate Air Quality Control Region. The Metropolitan Dayton Intrastate Air Quality Control Region consists of the territorial area encompassed by...

  16. 40 CFR 81.59 - Cumberland-Keyser Interstate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.59 Cumberland-Keyser Interstate Air Quality Control Region. The Cumberland-Keyser Interstate Air Quality Control Region (Maryland-West Virginia) has been revised to...

  17. 40 CFR 81.62 - Northeast Mississippi Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.62 Northeast Mississippi Intrastate Air Quality Control Region. The Alabama-Mississippi-Tennessee Interstate Air Quality Control Region has been renamed the...

  18. 40 CFR 81.30 - Southeastern Wisconsin Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.30 Southeastern Wisconsin Intrastate Air Quality Control Region. The Metropolitan Milwaukee Intrastate Air Quality Control Region (Wisconsin) has been renamed the...

  19. 40 CFR 81.19 - Metropolitan Boston Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.19 Metropolitan Boston Intrastate Air Quality Control Region. The Metropolitan Boston Intrastate Air Quality Control Region (Massachusetts) consists of the territorial...

  20. 40 CFR 81.76 - State of Hawaii Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false State of Hawaii Air Quality Control... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.76 State of Hawaii Air Quality Control Region. The State of Hawaii Air...

  1. 40 CFR 81.76 - State of Hawaii Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 18 2013-07-01 2013-07-01 false State of Hawaii Air Quality Control... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.76 State of Hawaii Air Quality Control Region. The State of Hawaii Air...

  2. 40 CFR 81.31 - Metropolitan Providence Interstate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.31 Metropolitan Providence Interstate Air Quality Control Region. The Metropolitan Providence Interstate Air Quality Control Region (Rhode Island-Massachusetts) consists of...

  3. 40 CFR 81.34 - Metropolitan Dayton Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.34 Metropolitan Dayton Intrastate Air Quality Control Region. The Metropolitan Dayton Intrastate Air Quality Control Region consists of the territorial area encompassed by...

  4. 40 CFR 81.44 - Metropolitan Memphis Interstate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.44 Metropolitan Memphis Interstate Air Quality Control Region. The Metropolitan Memphis Interstate Air Quality Control Region (Arkansas-Mississippi-Tennessee) consists of...

  5. 40 CFR 81.14 - Metropolitan Chicago Interstate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.14 Metropolitan Chicago Interstate Air Quality Control Region. The Metropolitan Chicago Interstate Air Quality Control Region (Illinois-Indiana) is revised to consist of...

  6. 40 CFR 81.19 - Metropolitan Boston Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.19 Metropolitan Boston Intrastate Air Quality Control Region. The Metropolitan Boston Intrastate Air Quality Control Region (Massachusetts) consists of the territorial...

  7. 40 CFR 81.28 - Metropolitan Baltimore Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.28 Metropolitan Baltimore Intrastate Air Quality Control Region. The Metropolitan Baltimore Intrastate Air Quality Control Region (Maryland) consists of the territorial...

  8. 40 CFR 81.23 - Southwest Pennsylvania Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.23 Southwest Pennsylvania Intrastate Air Quality Control Region. The Southwest Pennsylvania Intrastate Air Quality Control Region is redesignated to consist of the...

  9. 40 CFR 81.62 - Northeast Mississippi Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.62 Northeast Mississippi Intrastate Air Quality Control Region. The Alabama-Mississippi-Tennessee Interstate Air Quality Control Region has been renamed the...

  10. 40 CFR 81.16 - Metropolitan Denver Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.16 Metropolitan Denver Intrastate Air Quality Control Region. The Metropolitan Denver Intrastate Air Quality Control Region (Colorado) consists of the territorial...

  11. 40 CFR 81.20 - Metropolitan Cincinnati Interstate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.20 Metropolitan Cincinnati Interstate Air Quality Control Region. The Metropolitan Cincinnati Interstate Air Quality Control Region (Ohio-Kentucky-Indiana) is revised to consist...

  12. 40 CFR 81.47 - Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.47 Central Oklahoma Intrastate Air Quality Control Region. The Metropolitan Oklahoma Intrastate Air Quality Control Region has been renamed the Central Oklahoma...

  13. 40 CFR 81.43 - Metropolitan Toledo Interstate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.43 Metropolitan Toledo Interstate Air Quality Control Region. The Metropolitan Toledo Interstate Air Quality Control Region (Ohio-Michigan) consists of the territorial...

  14. 40 CFR 81.49 - Southeast Florida Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.49 Southeast Florida Intrastate Air Quality Control Region. The Southeast Florida Intrastate Air Quality Control Region is redesignated to consist of the territorial...

  15. 40 CFR 81.16 - Metropolitan Denver Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.16 Metropolitan Denver Intrastate Air Quality Control Region. The Metropolitan Denver Intrastate Air Quality Control Region (Colorado) consists of the territorial...

  16. 40 CFR 81.47 - Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.47 Central Oklahoma Intrastate Air Quality Control Region. The Metropolitan Oklahoma Intrastate Air Quality Control Region has been renamed the Central Oklahoma...

  17. 40 CFR 81.31 - Metropolitan Providence Interstate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.31 Metropolitan Providence Interstate Air Quality Control Region. The Metropolitan Providence Interstate Air Quality Control Region (Rhode Island-Massachusetts) consists of...

  18. 40 CFR 81.23 - Southwest Pennsylvania Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.23 Southwest Pennsylvania Intrastate Air Quality Control Region. The Southwest Pennsylvania Intrastate Air Quality Control Region is redesignated to consist of the...

  19. 40 CFR 81.75 - Metropolitan Charlotte Interstate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.75 Metropolitan Charlotte Interstate Air Quality Control Region. The Metropolitan Charlotte Interstate Air Quality Control Region (North Carolina-South Carolina) has been...

  20. 40 CFR 81.23 - Southwest Pennsylvania Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.23 Southwest Pennsylvania Intrastate Air Quality Control Region. The Southwest Pennsylvania Intrastate Air Quality Control Region is redesignated to consist of the...

  1. 40 CFR 81.34 - Metropolitan Dayton Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.34 Metropolitan Dayton Intrastate Air Quality Control Region. The Metropolitan Dayton Intrastate Air Quality Control Region consists of the territorial area encompassed by...

  2. 40 CFR 81.76 - State of Hawaii Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 18 2012-07-01 2012-07-01 false State of Hawaii Air Quality Control... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.76 State of Hawaii Air Quality Control Region. The State of Hawaii Air...

  3. 40 CFR 81.20 - Metropolitan Cincinnati Interstate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.20 Metropolitan Cincinnati Interstate Air Quality Control Region. The Metropolitan Cincinnati Interstate Air Quality Control Region (Ohio-Kentucky-Indiana) is revised to consist...

  4. 40 CFR 81.44 - Metropolitan Memphis Interstate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.44 Metropolitan Memphis Interstate Air Quality Control Region. The Metropolitan Memphis Interstate Air Quality Control Region (Arkansas-Mississippi-Tennessee) consists of...

  5. 40 CFR 81.47 - Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.47 Central Oklahoma Intrastate Air Quality Control Region. The Metropolitan Oklahoma Intrastate Air Quality Control Region has been renamed the Central Oklahoma...

  6. 40 CFR 81.23 - Southwest Pennsylvania Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.23 Southwest Pennsylvania Intrastate Air Quality Control Region. The Southwest Pennsylvania Intrastate Air Quality Control Region is redesignated to consist of the...

  7. 40 CFR 81.49 - Southeast Florida Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.49 Southeast Florida Intrastate Air Quality Control Region. The Southeast Florida Intrastate Air Quality Control Region is redesignated to consist of the territorial...

  8. 40 CFR 81.59 - Cumberland-Keyser Interstate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.59 Cumberland-Keyser Interstate Air Quality Control Region. The Cumberland-Keyser Interstate Air Quality Control Region (Maryland-West Virginia) has been revised to...

  9. 40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of...

  10. 40 CFR 81.31 - Metropolitan Providence Interstate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.31 Metropolitan Providence Interstate Air Quality Control Region. The Metropolitan Providence Interstate Air Quality Control Region (Rhode Island-Massachusetts) consists of...

  11. 40 CFR 81.19 - Metropolitan Boston Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.19 Metropolitan Boston Intrastate Air Quality Control Region. The Metropolitan Boston Intrastate Air Quality Control Region (Massachusetts) consists of the territorial...

  12. 40 CFR 81.41 - Metropolitan Birmingham Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.41 Metropolitan Birmingham Intrastate Air Quality Control Region. The Metropolitan Birmingham Intrastate Air Quality Control Region (Alabama) has been revised to consist of...

  13. 40 CFR 81.41 - Metropolitan Birmingham Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.41 Metropolitan Birmingham Intrastate Air Quality Control Region. The Metropolitan Birmingham Intrastate Air Quality Control Region (Alabama) has been revised to consist of...

  14. 40 CFR 81.16 - Metropolitan Denver Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.16 Metropolitan Denver Intrastate Air Quality Control Region. The Metropolitan Denver Intrastate Air Quality Control Region (Colorado) consists of the territorial...

  15. 40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of...

  16. 40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of...

  17. 40 CFR 81.20 - Metropolitan Cincinnati Interstate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.20 Metropolitan Cincinnati Interstate Air Quality Control Region. The Metropolitan Cincinnati Interstate Air Quality Control Region (Ohio-Kentucky-Indiana) is revised to consist...

  18. 40 CFR 81.44 - Metropolitan Memphis Interstate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.44 Metropolitan Memphis Interstate Air Quality Control Region. The Metropolitan Memphis Interstate Air Quality Control Region (Arkansas-Mississippi-Tennessee) consists of...

  19. 40 CFR 81.41 - Metropolitan Birmingham Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.41 Metropolitan Birmingham Intrastate Air Quality Control Region. The Metropolitan Birmingham Intrastate Air Quality Control Region (Alabama) has been revised to consist of...

  20. 40 CFR 81.41 - Metropolitan Birmingham Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.41 Metropolitan Birmingham Intrastate Air Quality Control Region. The Metropolitan Birmingham Intrastate Air Quality Control Region (Alabama) has been revised to consist of...