RF driven sulfur lamp having driving electrodes arranged to cool the lamp

DOEpatents

Gabor, G.; Orr, T.R.; Greene, C.M.; Crawford, D.G.; Berman, S.M.

1998-10-20

A high intensity discharge lamp without mercury is disclosed radiating a selected spectrum of which can be almost entirely in the visible range from an envelope that contains a sulfur containing substance. The lamp utilizes a signal source that generates an excitation signal that is externally coupled to the exterior surface of the envelope to excite the enclosed sulfur containing substance. Various embodiments of the lamp use electrodes adjacent the envelope to couple the excitation signal thereto with the face of the electrodes shaped to complement the shape of the exterior surface of the envelope. Two shapes discussed are spherical and cylindrical. To minimize filamentary discharges each envelope may include an elongated stem affixed to the exterior thereof whereby a rotational subsystem spins the envelope. In yet another embodiment the envelope has a Dewar configuration with two electrodes, one positioned near the external curved side surface of the body, and a second to the inner surface of the hole through the envelope. Further, the envelope may contain a backfill of a selected inert gas to assist in the excitation of lamp with that backfill at a pressure of less than 1 atmosphere, wherein the backfill pressure is directly related to the increase or decrease of peak output and inversely related to the increase and decrease of the emitted spectrum from the envelope. The emitting fill can be less than 6 mg/cc, or at least 2 mg/cc of the envelope of a sulfur containing substance. 17 figs.

RF driven sulfur lamp having driving electrodes which face each other

DOEpatents

Gabor, G.; Orr, T.R.; Greene, C.M.; Crawford, D.G.; Berman, S.M.

1999-06-22

A high intensity discharge lamp without mercury is disclosed radiating a selected spectrum of which can be almost entirely in the visible range from an envelope that contains a sulfur containing substance. The lamp utilizes a signal source that generates an excitation signal that is externally coupled to the exterior surface of the envelope to excite the enclosed sulfur containing substance. Various embodiments of the lamp use electrodes adjacent the envelope to couple the excitation signal thereto with the face of the electrodes shaped to complement the shape of the exterior surface of the envelope. Two shapes discussed are spherical and cylindrical. To minimize filamentary discharges each envelope may include an elongated stem affixed to the exterior thereof whereby a rotational subsystem spins the envelope. In yet another embodiment the envelope has a Dewar configuration with two electrodes, one positioned near the external curved side surface of the body, and a second to the inner surface of the hole through the envelope. Further, the envelope may contain a backfill of a selected inert gas to assist in the excitation of lamp with that backfill at a pressure of less than 1 atmosphere, wherein the backfill pressure is directly related to the increase or decrease of peak output and inversely related to the increase and decrease of the emitted spectrum from the envelope. The emitting fill can be less than 6 mg/cc, or at least 2 mg/cc of the envelope of a sulfur containing substance. 17 figs.

RF driven sulfur lamp having driving electrodes which face each other

DOEpatents

Gabor, George; Orr, Thomas Robert; Greene, Charles Maurice; Crawford, Douglas Gordon; Berman, Samuel Maurice

1999-01-01

A high intensity discharge lamp without mercury is disclosed radiating a selected spectrum of which can be almost entirely in the visible range from an envelope that contains a sulfur containing substance. The lamp utilizes a signal source that generates an excitation signal that is externally coupled to the exterior surface of the envelope to excite the enclosed sulfur containing substance. Various embodiments of the lamp use electrodes adjacent the envelope to couple the excitation signal thereto with the face of the electrodes shaped to complement the shape of the exterior surface of the envelope. Two shapes discussed are spherical and cylindrical. To minimize filamentary discharges each envelope may include an elongated stem affixed to the exterior thereof whereby a rotational subsystem spins the envelope. In yet another embodiment the envelope has a Dewar configuration with two electrodes, one positioned near the external curved side surface of the body, and a second to the inner surface of the hole through the envelope. Further, the envelope may contain a backfill of a selected inert gas to assist in the excitation of lamp with that backfill at a pressure of less than 1 atmosphere, wherein the backfill pressure is directly related to the increase or decrease of peak output and inversely related to the increase and decrease of the emitted spectrum from the envelope. The emitting fill can be less than 6 mg/cc, or at least 2 mg/cc of the envelope of a sulfur containing substance.

Method and apparatus for controlling carrier envelope phase

DOEpatents

Chang, Zenghu [Manhattan, KS; Li, Chengquan [Sunnyvale, CA; Moon, Eric [Manhattan, KS

2011-12-06

A chirped pulse amplification laser system. The system generally comprises a laser source, a pulse modification apparatus including first and second pulse modification elements separated by a separation distance, a positioning element, a measurement device, and a feedback controller. The laser source is operable to generate a laser pulse and the pulse modification apparatus operable to modify at least a portion of the laser pulse. The positioning element is operable to reposition at least a portion of the pulse modification apparatus to vary the separation distance. The measurement device is operable to measure the carrier envelope phase of the generated laser pulse and the feedback controller is operable to control the positioning element based on the measured carrier envelope phase to vary the separation distance of the pulse modification elements and control the carrier envelope phase of laser pulses generated by the laser source.

14 CFR 121.423 - Pilot: Extended Envelope Training.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Pilot: Extended Envelope Training. 121.423... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Training Program § 121.423 Pilot: Extended Envelope Training. (a) Each certificate holder must include in its approved training program, the extended envelope...

Method of bonding

DOEpatents

Saller, deceased, Henry A.; Hodge, Edwin S.; Paprocki, Stanley J.; Dayton, Russell W.

1987-12-01

1. A method of making a fuel-containing structure for nuclear reactors, comprising providing an assembly comprising a plurality of fuel units; each fuel unit consisting of a core plate containing thermal-neutron-fissionable material, sheets of cladding metal on its bottom and top surfaces, said cladding sheets being of greater width and length than said core plates whereby recesses are formed at the ends and sides of said core plate, and end pieces and first side pieces of cladding metal of the same thickness as the core plate positioned in said recesses, the assembly further comprising a plurality of second side pieces of cladding metal engaging the cladding sheets so as to space the fuel units from one another, and a plurality of filler plates of an acid-dissolvable nonresilient material whose melting point is above 2000.degree. F., each filler plate being arranged between a pair of said second side pieces and the cladding plates of two adjacent fuel units, the filler plates having the same thickness as the second side pieces; the method further comprising enclosing the entire assembly in an envelope; evacuating the interior of the entire assembly through said envelope; applying inert gas under a pressure of about 10,000 psi to the outside of said envelope while at the same time heating the assembly to a temperature above the flow point of the cladding metal but below the melting point of any material of the assembly, whereby the envelope is pressed against the assembly and integral bonds are formed between plates, sheets, first side pieces, and end pieces and between the sheets and the second side pieces; slowly cooling the assembly to room temperature; removing the envelope; and dissolving the filler plates without attacking the cladding metal.

Studies of hydrodynamic events in stellar evolution. 3: Ejection of planetary nebulae

NASA Technical Reports Server (NTRS)

Sparks, W. M.; Kutter, G. S.

1973-01-01

The dynamic behavior of the H-rich envelope (0.101 solar mass) of an evolved star (1.1 solar mass) as the luminosity rises to 19000 solar luminosity during the second ascent of the red giant branch. For luminosities in the range 3100 L 19000 solar luminosity the H-rich envelope pulsates like a long-period variable (LPV) with periods of the order of a year. As L reaches 19000 solar luminosity, the entire H-rich envelope is ejected as a shell with speeds of a few 10 km/s. The ejection occurs on a timescale of a few LPV pulsation periods. This ejection is associated with the formation of a planetary nebula. The computations are based on an implicit hydrodynamic computer code. T- and RHO-dependent opacities and excitation and ionization energies are included. As the H-rich envelope is accelerated off the stellar core, the gap between envelope and core is approximated by a vacuum, filled with radiation. Across the vacuum, the luminosity is conserved and the anisotropy of the radiation is considered as well as the solid angle subtended by the remnant star at the inner surface of the H-rich envelope. Spherical symmetry and the diffusion approximation are assumed.

Flight Test Results on the Stability and Control of the F-15 Quiet Spike(TradeMark) Aircraft

NASA Technical Reports Server (NTRS)

Moua, Cheng M.; McWherter, Shaun C.; Cox, Timothy H.; Gera, Joe

2012-01-01

The Quiet Spike F-15B flight research program investigated supersonic shock reduction using a 24-ft sub-scale telescoping nose boom on an F-15B airplane. The program primary flight test objective was to collect flight data for aerodynamic and structural models validation up to 1.8 Mach. Other objectives were to validate the mechanical feasibility of a morphing fuselage at the operational conditions and determine the near-field shock wave characterization. The stability and controls objectives were to assess the effect of the spike on the stability, controllability, and handling qualities of the aircraft and to ensure adequate stability margins across the entire research flight envelop. The two main stability and controls issues were the effects of the telescoping nose boom influenced aerodynamics on the F-15B aircraft flight dynamics and air data and angle of attack sensors. This paper reports on the stability and controls flight envelope clearance methods and flight test analysis of the F-15B Quiet Spike. Brief pilot commentary on typical piloting tasks, approach and landing, refueling task, and air data sensitivity to the flight control system are also discussed in this report.

40 CFR 426.125 - Standards of performance for new sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Incandescent Lamp Envelope... manufacturing plant which produces incandescent lamp envelopes shall meet the following limitations with regard... incandescent lamp envelopes shall meet the following limitations with regard to the finishing operations...

MASS SEPARATORS

DOEpatents

Oppenheimer, F.; Bell, J.W.

1959-02-17

An improvement in the mounting arrangement for the ion source within the vacuum tank of a calutron is presented. The entire source is supported by the vacuum envelope through the medium of a bracket secured to a removable face plate. The bracket forms a supporting platform that is generally transverse to the magnetic field. The ion generator is mounted on a pedestal-type insulator supported on the bracket, and the hot leads are brought into the vacuum envelope through a tubular elbow connected to the vacuum envelope, having the axis of its outer opening aligned with the magnetic field at which point a bushing-type insulator is employed. With this arrangement thc ion source is maintained at a positive potential with respect to the vacuum tank and the problem of electron bombardment of the insulator is considerably reduced.

Definition and means of maintaining the criticality detectors and alarms portion of the PFP safety envelope

DOE Office of Scientific and Technical Information (OSTI.GOV)

White, W.F.

The purpose of this document is to provide the definition and means of maintaining the Safety Envelope (SE) related to the Criticality Alarm System (CAS). This document provides amplification of the Limiting Condition for Operation (LCO) described in the Plutonium Finishing Plant (PFP) Operational Safety Requirements (OSR), WHC-SD-CP-OSR-010, Rev. 0, 1994, Section 3.1.2, Criticality Detectors and Alarms. This document, with its appendices, provides the following: (1) System functional requirements for determining system operability (Section 3); (2) A list of annotated system block diagrams which indicate the safety envelope boundaries (Appendix C); (3) A list of the Safety Class 1 andmore » 2 Safety Envelope (SC-1/2 SE) equipment for input into the Master Component Index (Appendix B); (4) Functional requirements for individual SC-1/2 SE components, including appropriate setpoints and process parameters (Section 6 and Appendix A); (5) A list of the operational, maintenance and surveillance procedures necessary to operate and maintain the SC-1/2 SE components as required by the LCO (Section 6 and Appendix A).« less

Validation of High-Fidelity Reactor Physics Models for Support of the KJRR Experimental Campaign in the Advanced Test Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nigg, David W.; Nielsen, Joseph W.; Norman, Daren R.

The Korea Atomic Energy Research Institute is currently in the process of qualifying a Low-Enriched Uranium fuel element design for the new Ki-Jang Research Reactor (KJRR). As part of this effort, a prototype KJRR fuel element was irradiated for several operating cycles in the Northeast Flux Trap of the Advanced Test Reactor (ATR) at the Idaho National Laboratory. The KJRR fuel element contained a very large quantity of fissile material (618g 235U) in comparison with historical ATR experiment standards (<1g 235U), and its presence in the ATR flux trap was expected to create a neutronic configuration that would be wellmore » outside of the approved validation envelope for the reactor physics analysis methods used to support ATR operations. Accordingly it was necessary, prior to high-power irradiation of the KJRR fuel element in the ATR, to conduct an extensive set of new low-power physics measurements with the KJRR fuel element installed in the ATR Critical Facility (ATRC), a companion facility to the ATR that is located in an immediately adjacent building, sharing the same fuel handling and storage canal. The new measurements had the objective of expanding the validation envelope for the computational reactor physics tools used to support ATR operations and safety analysis to include the planned KJRR irradiation in the ATR and similar experiments that are anticipated in the future. The computational and experimental results demonstrated that the neutronic behavior of the KJRR fuel element in the ATRC is well-understood, both in terms of its general effects on core excess reactivity and fission power distributions, its effects on the calibration of the core lobe power measurement system, as well as in terms of its own internal fission rate distribution and total fission power per unit ATRC core power. Taken as a whole, these results have significantly extended the ATR physics validation envelope, thereby enabling an entire new class of irradiation experiments.« less

Discriminating Simulated Vocal Tremor Source Using Amplitude Modulation Spectra

PubMed Central

Carbonell, Kathy M.; Lester, Rosemary A.; Story, Brad H.; Lotto, Andrew J.

2014-01-01

Objectives/Hypothesis Sources of vocal tremor are difficult to categorize perceptually and acoustically. This paper describes a preliminary attempt to discriminate vocal tremor sources through the use of spectral measures of the amplitude envelope. The hypothesis is that different vocal tremor sources are associated with distinct patterns of acoustic amplitude modulations. Study Design Statistical categorization methods (discriminant function analysis) were used to discriminate signals from simulated vocal tremor with different sources using only acoustic measures derived from the amplitude envelopes. Methods Simulations of vocal tremor were created by modulating parameters of a vocal fold model corresponding to oscillations of respiratory driving pressure (respiratory tremor), degree of vocal fold adduction (adductory tremor) and fundamental frequency of vocal fold vibration (F0 tremor). The acoustic measures were based on spectral analyses of the amplitude envelope computed across the entire signal and within select frequency bands. Results The signals could be categorized (with accuracy well above chance) in terms of the simulated tremor source using only measures of the amplitude envelope spectrum even when multiple sources of tremor were included. Conclusions These results supply initial support for an amplitude-envelope based approach to identify the source of vocal tremor and provide further evidence for the rich information about talker characteristics present in the temporal structure of the amplitude envelope. PMID:25532813

On Fock-space representations of quantized enveloping algebras related to noncommutative differential geometry

NASA Astrophysics Data System (ADS)

Jurčo, B.; Schlieker, M.

1995-07-01

In this paper explicitly natural (from the geometrical point of view) Fock-space representations (contragradient Verma modules) of the quantized enveloping algebras are constructed. In order to do so, one starts from the Gauss decomposition of the quantum group and introduces the differential operators on the corresponding q-deformed flag manifold (assumed as a left comodule for the quantum group) by a projection to it of the right action of the quantized enveloping algebra on the quantum group. Finally, the representatives of the elements of the quantized enveloping algebra corresponding to the left-invariant vector fields on the quantum group are expressed as first-order differential operators on the q-deformed flag manifold.

Envelope contributions to the representation of interaural time difference in the forebrain of barn owls.

PubMed

Tellers, Philipp; Lehmann, Jessica; Führ, Hartmut; Wagner, Hermann

2017-09-01

Birds and mammals use the interaural time difference (ITD) for azimuthal sound localization. While barn owls can use the ITD of the stimulus carrier frequency over nearly their entire hearing range, mammals have to utilize the ITD of the stimulus envelope to extend the upper frequency limit of ITD-based sound localization. ITD is computed and processed in a dedicated neural circuit that consists of two pathways. In the barn owl, ITD representation is more complex in the forebrain than in the midbrain pathway because of the combination of two inputs that represent different ITDs. We speculated that one of the two inputs includes an envelope contribution. To estimate the envelope contribution, we recorded ITD response functions for correlated and anticorrelated noise stimuli in the barn owl's auditory arcopallium. Our findings indicate that barn owls, like mammals, represent both carrier and envelope ITDs of overlapping frequency ranges, supporting the hypothesis that carrier and envelope ITD-based localization are complementary beyond a mere extension of the upper frequency limit. NEW & NOTEWORTHY The results presented in this study show for the first time that the barn owl is able to extract and represent the interaural time difference (ITD) information conveyed by the envelope of a broadband acoustic signal. Like mammals, the barn owl extracts the ITD of the envelope and the carrier of a signal from the same frequency range. These results are of general interest, since they reinforce a trend found in neural signal processing across different species. Copyright © 2017 the American Physiological Society.

Computing the Envelope for Stepwise Constant Resource Allocations

NASA Technical Reports Server (NTRS)

Muscettola, Nicola; Clancy, Daniel (Technical Monitor)

2001-01-01

Estimating tight resource level is a fundamental problem in the construction of flexible plans with resource utilization. In this paper we describe an efficient algorithm that builds a resource envelope, the tightest possible such bound. The algorithm is based on transforming the temporal network of resource consuming and producing events into a flow network with noises equal to the events and edges equal to the necessary predecessor links between events. The incremental solution of a staged maximum flow problem on the network is then used to compute the time of occurrence and the height of each step of the resource envelope profile. The staged algorithm has the same computational complexity of solving a maximum flow problem on the entire flow network. This makes this method computationally feasible for use in the inner loop of search-based scheduling algorithms.

Computing the Envelope for Stepwise-Constant Resource Allocations

NASA Technical Reports Server (NTRS)

Muscettola, Nicola; Clancy, Daniel (Technical Monitor)

2002-01-01

Computing tight resource-level bounds is a fundamental problem in the construction of flexible plans with resource utilization. In this paper we describe an efficient algorithm that builds a resource envelope, the tightest possible such bound. The algorithm is based on transforming the temporal network of resource consuming and producing events into a flow network with nodes equal to the events and edges equal to the necessary predecessor links between events. A staged maximum flow problem on the network is then used to compute the time of occurrence and the height of each step of the resource envelope profile. Each stage has the same computational complexity of solving a maximum flow problem on the entire flow network. This makes this method computationally feasible and promising for use in the inner loop of flexible-time scheduling algorithms.

Energy Management in Schools.

ERIC Educational Resources Information Center

Canadian School Trustees Association, Ottawa (Ontario).

This booklet provides the basic information for starting an energy conservation program. Guidelines for involving all school personnel and promoting energy conservation throughout the entire Canadian education system are provided. Outlined in the booklet are methods for climate proofing the building envelope and making the system air tight,…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murguia-Berthier, Ariadna; Ramirez-Ruiz, Enrico; Antoni, Andrea

During a common envelope (CE) episode in a binary system, the engulfed companion spirals to tighter orbital separations under the influence of drag from the surrounding envelope material. As this object sweeps through material with a steep radial gradient of density, net angular momentum is introduced into the flow, potentially leading to the formation of an accretion disk. The presence of a disk would have dramatic consequences for the outcome of the interaction because accretion might be accompanied by strong, polar outflows with enough energy to unbind the entire envelope. Without a detailed understanding of the necessary conditions for diskmore » formation during CE, therefore, it is difficult to accurately predict the population of merging compact binaries. This paper examines the conditions for disk formation around objects embedded within CEs using the “wind tunnel” formalism developed by MacLeod et al. We find that the formation of disks is highly dependent on the compressibility of the envelope material. Disks form only in the most compressible of stellar envelope gas, found in envelopes’ outer layers in zones of partial ionization. These zones are largest in low-mass stellar envelopes, but comprise small portions of the envelope mass and radius in all cases. We conclude that disk formation and associated accretion feedback in CE is rare, and if it occurs, transitory. The implication for LIGO black hole binary assembly is that by avoiding strong accretion feedback, CE interactions should still result in the substantial orbital tightening needed to produce merging binaries.« less

Lean, premixed, prevaporized fuel combustor conceptual design study

NASA Technical Reports Server (NTRS)

Fiorentino, A. J.; Greene, W.; Kim, J.

1979-01-01

Four combustor concepts, designed for the energy efficient engine, utilize variable geometry or other flow modulation techniques to control the equivalence ratio of the initial burning zone. Lean conditions are maintained at high power to control oxides of nitrogen while near stoichometric conditions are maintained at low power for low CO and THC emissions. Each concept was analyzed and ranked for its potential in meeting the goals of the program. Although the primary goal of the program is a low level of nitric oxide emissions at stratospheric cruise conditions, both the ground level EPA emission standards and combustor performance and operational requirements typical of advanced subsonic aircraft engines are retained as goals as well. Based on the analytical projections made, two of the concepts offer the potential of achieving the emission goals; however, the projected operational characteristics and reliability of any concept to perform satisfactorily over an entire aircraft flight envelope would require extensive experimental substantiation before engine adaptation can be considered.

Aircraft Flight Envelope Determination using Upset Detection and Physical Modeling Methods

NASA Technical Reports Server (NTRS)

Keller, Jeffrey D.; McKillip, Robert M. Jr.; Kim, Singwan

2009-01-01

The development of flight control systems to enhance aircraft safety during periods of vehicle impairment or degraded operations has been the focus of extensive work in recent years. Conditions adversely affecting aircraft flight operations and safety may result from a number of causes, including environmental disturbances, degraded flight operations, and aerodynamic upsets. To enhance the effectiveness of adaptive and envelope limiting controls systems, it is desirable to examine methods for identifying the occurrence of anomalous conditions and for assessing the impact of these conditions on the aircraft operational limits. This paper describes initial work performed toward this end, examining the use of fault detection methods applied to the aircraft for aerodynamic performance degradation identification and model-based methods for envelope prediction. Results are presented in which a model-based fault detection filter is applied to the identification of aircraft control surface and stall departure failures/upsets. This application is supported by a distributed loading aerodynamics formulation for the flight dynamics system reference model. Extensions for estimating the flight envelope due to generalized aerodynamic performance degradation are also described.

14 CFR 29.1517 - Limiting height-speed envelope.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limiting height-speed envelope. 29.1517... Operating Limitations § 29.1517 Limiting height-speed envelope. For Category A rotorcraft, if a range of heights exists at any speed, including zero, within which it is not possible to make a safe landing...

14 CFR 29.1517 - Limiting height-speed envelope.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Limiting height-speed envelope. 29.1517... Operating Limitations § 29.1517 Limiting height-speed envelope. For Category A rotorcraft, if a range of heights exists at any speed, including zero, within which it is not possible to make a safe landing...

Organic Molecules in Oxygen-Rich Circumstellar Envelopes: Methanol and Hydrocarbons

NASA Technical Reports Server (NTRS)

Charnley, S. B.; Tielens, A. G. G. M.; Kress, M. E.

1995-01-01

The existence of anomalously high abundances of gaseous CH4 has been invoked to explain the unexpectedly high abundances of the carbon-bearing molecules HCN and H2CO in the outflows from O-rich red giants. We have modelled the chemistry that proceeds in the outer envelope when CH4 is injected from the inner envelope. We find that photolysis by the interstellar radiation field drives an ion-neutral chemistry which produces several organic molecules. The calculated abundances of CH3OH, C2H and C2 can be comparable to those calculated for H2CO and HCN. Species such as C2H4, C2H2 and CH3CN can also be abundant. A search for CH3OH and C2H in several O-rich outflows known to exhibit strong HCN emission is needed. As it derives entirely from the CH4 photochain, is insensitive to the envelope temperature distribution, and has accessible transitions at millimetre wavelengths, the detection of the C2H radical would provide further indirect support for the presence of the hypothesized methane.

Potential of Aerostats for the Recovery of Disabled Main Battle Tanks and Other Heavy Military Vehicles and Equipment

DTIC Science & Technology

2007-08-01

designs and operates numerous passenger airships. The envelope structure consists of a laminated fabric envelope. This envelope is a large bag...Layered Aerostat Fabric This multi-layered laminate is designed to withstand the sun’s UV rays, acid rain and other environmental concerns. It is...a tough laminate , which inhibits gas loss while providing a high strength-to-weight ratio. The CL75 envelope used a laminate material woven with

Compact cyclone filter train for radiological and hazardous environments

DOEpatents

Bench, Thomas R.

1998-01-01

A compact cyclone filter train for the removal of hazardous and radiologi particles from a gaseous fluid medium which permits a small cyclone separator to be used in a very small space envelope due to the arrangement of the filter housing adjacent to the separator with the cyclone separator and the filters mounted on a plate. The entire unit will have a hoist connection at the center of gravity so that the entire unit including the separator, the filters, and the base can be lifted and repositioned as desired.

Dynamic Structural Fault Detection and Identification

NASA Technical Reports Server (NTRS)

Smith, Timothy; Reichenbach, Eric; Urnes, James M.

2009-01-01

Aircraft structures are designed to guarantee safety of flight in some required operational envelope. When the aircraft becomes structurally impaired, safety of flight may not be guaranteed within that previously safe operational envelope. In this case the safe operational envelope must be redefined in-flight and a means to prevent excursion from this new envelope must be implemented. A specific structural failure mode that may result in a reduced safe operating envelope, the exceedance of which could lead to catastrophic structural failure of the aircraft, will be addressed. The goal of the DFEAP program is the detection of this failure mode coupled with flight controls adaptation to limit critical loads in the damaged aircraft structure. The DFEAP program is working with an F/A-18 aircraft model. The composite wing skins are bonded to metallic spars in the wing substructure. Over time, it is possible that this bonding can deteriorate due to fatigue. In this case, the ability of the wing spar to transfer loading between the wing skins is reduced. This failure mode can translate to a reduced allowable compressive strain on the wing skin and could lead to catastrophic wing buckling if load limiting of the wing structure is not applied. The DFEAP program will make use of a simplified wing strain model for the healthy aircraft. The outputs of this model will be compared in real-time to onboard strain measurements at several locations on the aircraft wing. A damage condition is declared at a given location when the strain measurements differ sufficiently from the strain model. Parameter identification of the damaged structure wing strain parameters will be employed to provide load limiting control adaptation for the aircraft. This paper will discuss the simplified strain models used in the implementation and their interaction with the strain sensor measurements. Also discussed will be the damage detection and identification schemes employed and the means by which the damaged aircraft parameters will be used to provide load limiting that keeps the aircraft within the safe operational envelope.

Data Envelopment Analysis (DEA) Model in Operation Management

NASA Astrophysics Data System (ADS)

Malik, Meilisa; Efendi, Syahril; Zarlis, Muhammad

2018-01-01

Quality management is an effective system in operation management to develops, maintains, and improves quality from groups of companies that allow marketing, production, and service at the most economycal level as well as ensuring customer satisfication. Many companies are practicing quality management to improve their bussiness performance. One of performance measurement is through measurement of efficiency. One of the tools can be used to assess efficiency of companies performance is Data Envelopment Analysis (DEA). The aim of this paper is using Data Envelopment Analysis (DEA) model to assess efficiency of quality management. In this paper will be explained CCR, BCC, and SBM models to assess efficiency of quality management.

Double core evolution. 7: The infall of a neutron star through the envelope of its massive star companion

NASA Technical Reports Server (NTRS)

Terman, James L.; Taam, Ronald E.; Hernquist, Lars

1995-01-01

Binary systems with properties similar to those of high-mass X-ray binaries are evolved through the common envelope phase. Three-dimensional simulations show that the timescale of the infall phase of the neutron star depends upon the evolutionary state of its massive companion. We find that tidal torques more effectively accelerate common envelope evolution for companions in their late core helium-burning stage and that the infall phase is rapid (approximately several initial orbital periods). For less evolved companions the decay of the orbit is longer; however, once the neutron star is deeply embedded within the companion's envelope the timescale for orbital decay decreases rapidly. As the neutron star encounters the high-density region surrounding the helium core of its massive companion, the rate of energy loss from the orbit increases dramatically leading to either partial or nearly total envelope ejection. The outcome of the common envelope phase depends upon the structure of the evolved companion. In particular, it is found that the entire common envelope can be ejected by the interaction of the neutron star with a red supergiant companion in binaries with orbital periods similar to those of long-period Be X-ray binaries. For orbital periods greater than or approximately equal to 0.8-2 yr (for companions of mass 12-24 solar mass) it is likely that a binary will survive the common envelope phase. For these systems, the structure of the progenitor star is characterized by a steep density gradient above the helium core, and the common envelope phase ends with a spin up of the envelope to within 50%-60% of corotation and with a slow mass outflow. The efficiency of mass ejection is found to be approximately 30%-40%. For less evolved companions, there is insufficient energy in the orbit to unbind the common envelope and only a fraction of it is ejected. Since the timescale for orbital decay is always shorter than the mass-loss timescale from the common envelope, the two cores will likely merge to form a Thorne-Zytkow object. Implications for the origin of Cyg X-3, an X-ray source consisting of a Wolf-Rayet star and a compact companion, and for the fate of the remnant binary consisting of a helium star and a neutron star are briefly discussed.

Definition and Means of Maintaining the Emergency Notification and Evacuation System Portion of the Plutonium Finishing Plant (PFP) Safety Envelope

DOE Office of Scientific and Technical Information (OSTI.GOV)

WHITE, W.F.

2000-04-04

The purpose of this document is to provide the definition and means of maintaining the safety envelope (SE) for the Emergency Notification and Evacuation System (ENES). Together with the appendices, it provides: (1) The system requirements for determining system operability (Section 3.0); (2) Evaluations of equipment to determine the safety boundary for the system (Section 4.0); (3) List of system drawings that are annotated to show the SE boundaries (Appendix A); (4) Identification of the SE equipment by reference to systems and drawings (Appendix B); (5) Requirements for the individual SE equipment (Section 4.0); and (6) A list of themore » operational and surveillance procedures necessary to operate and maintain the system equipment within the SE (Sections 5.0 and 6.0). The Private Automatic Exchange (PAX) phones and PAX switchers are outside the safety envelope defined in WHC-SD-CP-OSR-010, Section 5.4.10, ''Safety Communication and Alarm Systems,'' Section 5.4.1 0.1, ''Major Components and Operating Characteristics,'' and Section 5.4.10.1.12, ''PAX System.'' The PAX override microphone system maintains the safety envelope, and functions as a backup to the evacuation sirens during an emergency.« less

Equilibrium of Global Amphibian Species Distributions with Climate

PubMed Central

Munguía, Mariana; Rahbek, Carsten; Rangel, Thiago F.; Diniz-Filho, Jose Alexandre F.; Araújo, Miguel B.

2012-01-01

A common assumption in bioclimatic envelope modeling is that species distributions are in equilibrium with contemporary climate. A number of studies have measured departures from equilibrium in species distributions in particular regions, but such investigations were never carried out for a complete lineage across its entire distribution. We measure departures of equilibrium with contemporary climate for the distributions of the world amphibian species. Specifically, we fitted bioclimatic envelopes for 5544 species using three presence-only models. We then measured the proportion of the modeled envelope that is currently occupied by the species, as a metric of equilibrium of species distributions with climate. The assumption was that the greater the difference between modeled bioclimatic envelope and the occupied distribution, the greater the likelihood that species distribution would not be at equilibrium with contemporary climate. On average, amphibians occupied 30% to 57% of their potential distributions. Although patterns differed across regions, there were no significant differences among lineages. Species in the Neotropic, Afrotropics, Indo-Malay, and Palaearctic occupied a smaller proportion of their potential distributions than species in the Nearctic, Madagascar, and Australasia. We acknowledge that our models underestimate non equilibrium, and discuss potential reasons for the observed patterns. From a modeling perspective our results support the view that at global scale bioclimatic envelope models might perform similarly across lineages but differently across regions. PMID:22511938

Compact cyclone filter train for radiological and hazardous environments

DOEpatents

Bench, T.R.

1998-04-28

A compact cyclone filter train is disclosed for the removal of hazardous and radiological particles from a gaseous fluid medium. This filter train permits a small cyclone separator to be used in a very small space envelope due to the arrangement of the filter housing adjacent to the separator with the cyclone separator and the filters mounted on a plate. The entire unit will have a hoist connection at the center of gravity so that the entire unit including the separator, the filters, and the base can be lifted and repositioned as desired. 3 figs.

Performance (Off-Design) Cycle Analysis for a Turbofan Engine With Interstage Turbine Burner

NASA Technical Reports Server (NTRS)

Liew, K. H.; Urip, E.; Yang, S. L.; Mattingly, J. D.; Marek, C. J.

2005-01-01

This report presents the performance of a steady-state, dual-spool, separate-exhaust turbofan engine, with an interstage turbine burner (ITB) serving as a secondary combustor. The ITB, which is located in the transition duct between the high- and the low-pressure turbines, is a relatively new concept for increasing specific thrust and lowering pollutant emissions in modern jet-engine propulsion. A detailed off-design performance analysis of ITB engines is written in Microsoft(Registered Trademark) Excel (Redmond, Washington) macrocode with Visual Basic Application to calculate engine performances over the entire operating envelope. Several design-point engine cases are pre-selected using a parametric cycle-analysis code developed previously in Microsoft(Registered Trademark) Excel, for off-design analysis. The off-design code calculates engine performances (i.e. thrust and thrust-specific-fuel-consumption) at various flight conditions and throttle settings.

Envelope Responses in Single-Trial EEG Indicate Attended Speaker in a Cocktail Party

DTIC Science & Technology

2013-06-20

users to modulate their brain activity, such as motor rhythms, in order to signal intent [13], but these often require considerable training . Other...BCIs forgo training and instead have subjects make choices by attending to one of multiple visual and/or auditory stimuli. By presenting each stimulus...modulated). An envelope-based BCI could operate on more naturalistic auditory stimuli, such as speech or music . For example, an envelope-based BCI

Envelope: interactive software for modeling and fitting complex isotope distributions.

PubMed

Sykes, Michael T; Williamson, James R

2008-10-20

An important aspect of proteomic mass spectrometry involves quantifying and interpreting the isotope distributions arising from mixtures of macromolecules with different isotope labeling patterns. These patterns can be quite complex, in particular with in vivo metabolic labeling experiments producing fractional atomic labeling or fractional residue labeling of peptides or other macromolecules. In general, it can be difficult to distinguish the contributions of species with different labeling patterns to an experimental spectrum and difficult to calculate a theoretical isotope distribution to fit such data. There is a need for interactive and user-friendly software that can calculate and fit the entire isotope distribution of a complex mixture while comparing these calculations with experimental data and extracting the contributions from the differently labeled species. Envelope has been developed to be user-friendly while still being as flexible and powerful as possible. Envelope can simultaneously calculate the isotope distributions for any number of different labeling patterns for a given peptide or oligonucleotide, while automatically summing these into a single overall isotope distribution. Envelope can handle fractional or complete atom or residue-based labeling, and the contribution from each different user-defined labeling pattern is clearly illustrated in the interactive display and is individually adjustable. At present, Envelope supports labeling with 2H, 13C, and 15N, and supports adjustments for baseline correction, an instrument accuracy offset in the m/z domain, and peak width. Furthermore, Envelope can display experimental data superimposed on calculated isotope distributions, and calculate a least-squares goodness of fit between the two. All of this information is displayed on the screen in a single graphical user interface. Envelope supports high-quality output of experimental and calculated distributions in PNG or PDF format. Beyond simply comparing calculated distributions to experimental data, Envelope is useful for planning or designing metabolic labeling experiments, by visualizing hypothetical isotope distributions in order to evaluate the feasibility of a labeling strategy. Envelope is also useful as a teaching tool, with its real-time display capabilities providing a straightforward way to illustrate the key variable factors that contribute to an observed isotope distribution. Envelope is a powerful tool for the interactive calculation and visualization of complex isotope distributions for comparison to experimental data. It is available under the GNU General Public License from http://williamson.scripps.edu/envelope/.

Adaptive envelope protection methods for aircraft

NASA Astrophysics Data System (ADS)

Unnikrishnan, Suraj

Carefree handling refers to the ability of a pilot to operate an aircraft without the need to continuously monitor aircraft operating limits. At the heart of all carefree handling or maneuvering systems, also referred to as envelope protection systems, are algorithms and methods for predicting future limit violations. Recently, envelope protection methods that have gained more acceptance, translate limit proximity information to its equivalent in the control channel. Envelope protection algorithms either use very small prediction horizon or are static methods with no capability to adapt to changes in system configurations. Adaptive approaches maximizing prediction horizon such as dynamic trim, are only applicable to steady-state-response critical limit parameters. In this thesis, a new adaptive envelope protection method is developed that is applicable to steady-state and transient response critical limit parameters. The approach is based upon devising the most aggressive optimal control profile to the limit boundary and using it to compute control limits. Pilot-in-the-loop evaluations of the proposed approach are conducted at the Georgia Tech Carefree Maneuver lab for transient longitudinal hub moment limit protection. Carefree maneuvering is the dual of carefree handling in the realm of autonomous Uninhabited Aerial Vehicles (UAVs). Designing a flight control system to fully and effectively utilize the operational flight envelope is very difficult. With the increasing role and demands for extreme maneuverability there is a need for developing envelope protection methods for autonomous UAVs. In this thesis, a full-authority automatic envelope protection method is proposed for limit protection in UAVs. The approach uses adaptive estimate of limit parameter dynamics and finite-time horizon predictions to detect impending limit boundary violations. Limit violations are prevented by treating the limit boundary as an obstacle and by correcting nominal control/command inputs to track a limit parameter safe-response profile near the limit boundary. The method is evaluated using software-in-the-loop and flight evaluations on the Georgia Tech unmanned rotorcraft platform---GTMax. The thesis also develops and evaluates an extension for calculating control margins based on restricting limit parameter response aggressiveness near the limit boundary.

A Joint Method of Envelope Inversion Combined with Hybrid-domain Full Waveform Inversion

NASA Astrophysics Data System (ADS)

CUI, C.; Hou, W.

2017-12-01

Full waveform inversion (FWI) aims to construct high-precision subsurface models by fully using the information in seismic records, including amplitude, travel time, phase and so on. However, high non-linearity and the absence of low frequency information in seismic data lead to the well-known cycle skipping problem and make inversion easily fall into local minima. In addition, those 3D inversion methods that are based on acoustic approximation ignore the elastic effects in real seismic field, and make inversion harder. As a result, the accuracy of final inversion results highly relies on the quality of initial model. In order to improve stability and quality of inversion results, multi-scale inversion that reconstructs subsurface model from low to high frequency are applied. But, the absence of very low frequencies (< 3Hz) in field data is still bottleneck in the FWI. By extracting ultra low-frequency data from field data, envelope inversion is able to recover low wavenumber model with a demodulation operator (envelope operator), though the low frequency data does not really exist in field data. To improve the efficiency and viability of the inversion, in this study, we proposed a joint method of envelope inversion combined with hybrid-domain FWI. First, we developed 3D elastic envelope inversion, and the misfit function and the corresponding gradient operator were derived. Then we performed hybrid-domain FWI with envelope inversion result as initial model which provides low wavenumber component of model. Here, forward modeling is implemented in the time domain and inversion in the frequency domain. To accelerate the inversion, we adopt CPU/GPU heterogeneous computing techniques. There were two levels of parallelism. In the first level, the inversion tasks are decomposed and assigned to each computation node by shot number. In the second level, GPU multithreaded programming is used for the computation tasks in each node, including forward modeling, envelope extraction, DFT (discrete Fourier transform) calculation and gradients calculation. Numerical tests demonstrated that the combined envelope inversion + hybrid-domain FWI could obtain much faithful and accurate result than conventional hybrid-domain FWI. The CPU/GPU heterogeneous parallel computation could improve the performance speed.

Efficient common-envelope ejection through dust-driven winds

NASA Astrophysics Data System (ADS)

Glanz, Hila; Perets, Hagai B.

2018-04-01

Common-envelope evolution (CEE) is the short-lived phase in the life of an interacting binary-system during which two stars orbit inside a single shared envelope. Such evolution is thought to lead to the inspiral of the binary, the ejection of the extended envelope and the formation of a remnant short-period binary. However, detailed hydrodynamical models of CEE encounter major difficulties. They show that following the inspiral most of the envelope is not ejected; though it expands to larger separations, it remains bound to the binary. Here we propose that dust-driven winds can be produced following the CEE. These can evaporate the envelope following similar processes operating in the ejection of the envelopes of AGB stars. Pulsations in an AGB-star drives the expansion of its envelope, allowing the material to cool down to low temperatures thus enabling dust condensation. Radiation pressure on the dust accelerates it, and through its coupling to the gas it drives winds which eventually completely erode the envelope. We show that the inspiral phase in CE-binaries can effectively replace the role of stellar pulsation and drive the CE expansion to scales comparable with those of AGB stars, and give rise to efficient mass-loss through dust-driven winds.

Reality Check Algorithm for Complex Sources in Early Warning

NASA Astrophysics Data System (ADS)

Karakus, G.; Heaton, T. H.

2013-12-01

In almost all currently operating earthquake early warning (EEW) systems, presently available seismic data are used to predict future shaking. In most cases, location and magnitude are estimated. We are developing an algorithm to test the goodness of that prediction in real time. We monitor envelopes of acceleration, velocity, and displacement; if they deviate significantly from the envelope predicted by Cua's envelope gmpe's then we declare an overfit (perhaps false alarm) or an underfit (possibly a larger event has just occurred). This algorithm is designed to provide a robust measure and to work as quickly as possible in real-time. We monitor the logarithm of the ratio between the envelopes of the ongoing observed event and the envelopes derived from the predicted envelopes of channels of ground motion of the Virtual Seismologist (VS) (Cua, G. and Heaton, T.). Then, we recursively filter this result with a simple running median (de-spiking operator) to minimize the effect of one single high value. Depending on the result of the filtered value we make a decision such as if this value is large enough (e.g., >1), then we would declare, 'that a larger event is in progress', or similarly if this value is small enough (e.g., <-1), then we would declare a false alarm. We design the algorithm to work at a wide range of amplitude scales; that is, it should work for both small and large events.

Evolution of Space Shuttle Range Safety Ascent Flight Envelope Design

NASA Technical Reports Server (NTRS)

Brewer, Joan; Davis, Jerel; Glenn, Christopher

2011-01-01

For every space vehicle launch from the Eastern Range in Florida, the range user must provide specific Range Safety (RS) data products to the Air Force's 45th Space Wing in order to obtain flight plan approval. One of these data products is a set of RS ascent flight envelope trajectories that define the normal operating region of the vehicle during powered flight. With the Shuttle Program launching 135 manned missions over a 30-year period, 135 envelope sets were delivered to the range. During this time, the envelope methodology and design process evolved to support mission changes, maintain high data quality, and reduce costs. The purpose of this document is to outline the shuttle envelope design evolution and capture the lessons learned that could apply to future spaceflight endeavors.

On the possibility of enrichment and differentiation in gas giants during birth by disk instability

NASA Astrophysics Data System (ADS)

Boley, Aaron C.; Durisen, Richard H.

2011-11-01

We investigate the coupling between solids and gas during the formation of gas giant planets by disk fragmentation in the outer regions of massive disks. We find that fragments can become differentiated at birth. Even if an entire clump does not survive, differentiation could create solids cores that survive to accrete gaseous envelopes later.

Robustness Analysis and Reliable Flight Regime Estimation of an Integrated Resilent Control System for a Transport Aircraft

NASA Technical Reports Server (NTRS)

Shin, Jong-Yeob; Belcastro, Christine

2008-01-01

Formal robustness analysis of aircraft control upset prevention and recovery systems could play an important role in their validation and ultimate certification. As a part of the validation process, this paper describes an analysis method for determining a reliable flight regime in the flight envelope within which an integrated resilent control system can achieve the desired performance of tracking command signals and detecting additive faults in the presence of parameter uncertainty and unmodeled dynamics. To calculate a reliable flight regime, a structured singular value analysis method is applied to analyze the closed-loop system over the entire flight envelope. To use the structured singular value analysis method, a linear fractional transform (LFT) model of a transport aircraft longitudinal dynamics is developed over the flight envelope by using a preliminary LFT modeling software tool developed at the NASA Langley Research Center, which utilizes a matrix-based computational approach. The developed LFT model can capture original nonlinear dynamics over the flight envelope with the ! block which contains key varying parameters: angle of attack and velocity, and real parameter uncertainty: aerodynamic coefficient uncertainty and moment of inertia uncertainty. Using the developed LFT model and a formal robustness analysis method, a reliable flight regime is calculated for a transport aircraft closed-loop system.

Sound envelope processing in the developing human brain: A MEG study.

PubMed

Tang, Huizhen; Brock, Jon; Johnson, Blake W

2016-02-01

This study investigated auditory cortical processing of linguistically-relevant temporal modulations in the developing brains of young children. Auditory envelope following responses to white noise amplitude modulated at rates of 1-80 Hz in healthy children (aged 3-5 years) and adults were recorded using a paediatric magnetoencephalography (MEG) system and a conventional MEG system, respectively. For children, there were envelope following responses to slow modulations but no significant responses to rates higher than about 25 Hz, whereas adults showed significant envelope following responses to almost the entire range of stimulus rates. Our results show that the auditory cortex of preschool-aged children has a sharply limited capacity to process rapid amplitude modulations in sounds, as compared to the auditory cortex of adults. These neurophysiological results are consistent with previous psychophysical evidence for a protracted maturational time course for auditory temporal processing. The findings are also in good agreement with current linguistic theories that posit a perceptual bias for low frequency temporal information in speech during language acquisition. These insights also have clinical relevance for our understanding of language disorders that are associated with difficulties in processing temporal information in speech. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Assembly of viral particles in Xenopus oocytes: pre-surface-antigens regulate secretion of the hepatitis B viral surface envelope particle.

PubMed Central

Standring, D N; Ou, J H; Rutter, W J

1986-01-01

Infection with hepatitis B virus (HBV) is associated with the production of a viral envelope particle that contains membrane lipids, surface antigen (S), and two presurface-antigens (pre-S) comprised of the entire S moiety with approximately 55 (pre-S2) and 174 (pre-S1) additional NH2-terminal amino acids. We show here that Xenopus oocytes injected with synthetic S mRNA assemble and secrete characteristic 22-nm viral envelope particles. In contrast, pre-S1 and pre-S2 antigens are synthesized but not secreted. By coinjecting mRNAs, we found that synthesis of high levels of pre-S proteins specifically inhibits S antigen secretion. On the other hand, high levels of S synthesis can drive the secretion of small amounts of either pre-S antigen. These observations are consistent with a model for viral envelope assembly in which both S and pre-S proteins are incorporated into a multimeric particle, presumably via interactions between the S protein domains, while the pre-S amino-terminal moieties regulate the secretion of this structure. Our results indicate that Xenopus oocytes will provide a powerful system for studying the morphogenesis of simple structures of viral or cellular origin. Images PMID:3467308

Remodeling of the Nuclear Envelope and Lamina during Bovine Preimplantation Development and Its Functional Implications

PubMed Central

Popken, Jens; Graf, Alexander; Krebs, Stefan; Blum, Helmut; Schmid, Volker J.; Strauss, Axel; Guengoer, Tuna; Zakhartchenko, Valeri; Wolf, Eckhard; Cremer, Thomas

2015-01-01

The present study demonstrates a major remodeling of the nuclear envelope and its underlying lamina during bovine preimplantation development. Up to the onset of major embryonic genome activation (MGA) at the 8-cell stage nuclei showed a non-uniform distribution of nuclear pore complexes (NPCs). NPCs were exclusively present at sites where DNA contacted the nuclear lamina. Extended regions of the lamina, which were not contacted by DNA, lacked NPCs. In post-MGA nuclei the whole lamina was contacted rather uniformly by DNA. Accordingly, NPCs became uniformly distributed throughout the entire nuclear envelope. These findings shed new light on the conditions which control the integration of NPCs into the nuclear envelope. The switch from maternal to embryonic production of mRNAs was accompanied by multiple invaginations covered with NPCs, which may serve the increased demands of mRNA export and protein import. Other invaginations, as well as interior nuclear segments and vesicles without contact to the nuclear envelope, were exclusively positive for lamin B. Since the abundance of these invaginations and vesicles increased in concert with a massive nuclear volume reduction, we suggest that they reflect a mechanism for fitting the nuclear envelope and its lamina to a shrinking nuclear size during bovine preimplantation development. In addition, a deposit of extranuclear clusters of NUP153 (a marker for NPCs) without associated lamin B was frequently observed from the zygote stage up to MGA. Corresponding RNA-Seq data revealed deposits of spliced, maternally provided NUP153 mRNA and little unspliced, newly synthesized RNA prior to MGA, which increased strongly at the initiation of embryonic expression of NUP153 at MGA. PMID:25932910

Remodeling of the Nuclear Envelope and Lamina during Bovine Preimplantation Development and Its Functional Implications.

PubMed

Popken, Jens; Graf, Alexander; Krebs, Stefan; Blum, Helmut; Schmid, Volker J; Strauss, Axel; Guengoer, Tuna; Zakhartchenko, Valeri; Wolf, Eckhard; Cremer, Thomas

2015-01-01

The present study demonstrates a major remodeling of the nuclear envelope and its underlying lamina during bovine preimplantation development. Up to the onset of major embryonic genome activation (MGA) at the 8-cell stage nuclei showed a non-uniform distribution of nuclear pore complexes (NPCs). NPCs were exclusively present at sites where DNA contacted the nuclear lamina. Extended regions of the lamina, which were not contacted by DNA, lacked NPCs. In post-MGA nuclei the whole lamina was contacted rather uniformly by DNA. Accordingly, NPCs became uniformly distributed throughout the entire nuclear envelope. These findings shed new light on the conditions which control the integration of NPCs into the nuclear envelope. The switch from maternal to embryonic production of mRNAs was accompanied by multiple invaginations covered with NPCs, which may serve the increased demands of mRNA export and protein import. Other invaginations, as well as interior nuclear segments and vesicles without contact to the nuclear envelope, were exclusively positive for lamin B. Since the abundance of these invaginations and vesicles increased in concert with a massive nuclear volume reduction, we suggest that they reflect a mechanism for fitting the nuclear envelope and its lamina to a shrinking nuclear size during bovine preimplantation development. In addition, a deposit of extranuclear clusters of NUP153 (a marker for NPCs) without associated lamin B was frequently observed from the zygote stage up to MGA. Corresponding RNA-Seq data revealed deposits of spliced, maternally provided NUP153 mRNA and little unspliced, newly synthesized RNA prior to MGA, which increased strongly at the initiation of embryonic expression of NUP153 at MGA.

Full-Waveform Envelope Templates for Low Magnitude Discrimination and Yield Estimation at Local and Regional Distances with Application to the North Korean Nuclear Tests

NASA Astrophysics Data System (ADS)

Yoo, S. H.

2017-12-01

Monitoring seismologists have successfully used seismic coda for event discrimination and yield estimation for over a decade. In practice seismologists typically analyze long-duration, S-coda signals with high signal-to-noise ratios (SNR) at regional and teleseismic distances, since the single back-scattering model reasonably predicts decay of the late coda. However, seismic monitoring requirements are shifting towards smaller, locally recorded events that exhibit low SNR and short signal lengths. To be successful at characterizing events recorded at local distances, we must utilize the direct-phase arrivals, as well as the earlier part of the coda, which is dominated by multiple forward scattering. To remedy this problem, we have developed a new hybrid method known as full-waveform envelope template matching to improve predicted envelope fits over the entire waveform and account for direct-wave and early coda complexity. We accomplish this by including a multiple forward-scattering approximation in the envelope modeling of the early coda. The new hybrid envelope templates are designed to fit local and regional full waveforms and produce low-variance amplitude estimates, which will improve yield estimation and discrimination between earthquakes and explosions. To demonstrate the new technique, we applied our full-waveform envelope template-matching method to the six known North Korean (DPRK) underground nuclear tests and four aftershock events following the September 2017 test. We successfully discriminated the event types and estimated the yield for all six nuclear tests. We also applied the same technique to the 2015 Tianjin explosions in China, and another suspected low-yield explosion at the DPRK test site on May 12, 2010. Our results show that the new full-waveform envelope template-matching method significantly improves upon longstanding single-scattering coda prediction techniques. More importantly, the new method allows monitoring seismologists to extend coda-based techniques to lower magnitude thresholds and low-yield local explosions.

Tone signal generator for producing multioperator tone signals using an operator circuit including a waveform generator, a selector and an enveloper

DOEpatents

Dong, Qiujie; Jenkins, Michael V.; Bernadas, Salvador R.

1997-01-01

A frequency modulation (FM) tone signal generator for generating a FM tone signal is disclosed. The tone signal generator includes a waveform generator having a plurality of wave tables, a selector and an enveloper. The waveform generator furnishes a waveform signal in response to a phase angle address signal. Each wave table stores a different waveform. The selector selects one of the wave tables in response to a plurality of selection signals such that the selected wave table largely provides the waveform signal upon being addressed largely by the phase angle address signal. Selection of the selected wave table varies with each selection signal. The enveloper impresses an envelope signal on the waveform signal. The envelope signal is used as a carrier or modulator for generating the FM tone signal.

Modeling study of seated reach envelopes based on spherical harmonics with consideration of the difficulty ratings.

PubMed

Yu, Xiaozhi; Ren, Jindong; Zhang, Qian; Liu, Qun; Liu, Honghao

2017-04-01

Reach envelopes are very useful for the design and layout of controls. In building reach envelopes, one of the key problems is to represent the reach limits accurately and conveniently. Spherical harmonics are proved to be accurate and convenient method for fitting of the reach capability envelopes. However, extensive study are required on what components of spherical harmonics are needed in fitting the envelope surfaces. For applications in the vehicle industry, an inevitable issue is to construct reach limit surfaces with consideration of the seating positions of the drivers, and it is desirable to use population envelopes rather than individual envelopes. However, it is relatively inconvenient to acquire reach envelopes via a test considering the seating positions of the drivers. In addition, the acquired envelopes are usually unsuitable for use with other vehicle models because they are dependent on the current cab packaging parameters. Therefore, it is of great significance to construct reach envelopes for real vehicle conditions based on individual capability data considering seating positions. Moreover, traditional reach envelopes provide little information regarding the assessment of reach difficulty. The application of reach envelopes will improve design quality by providing difficulty-rating information about reach operations. In this paper, using the laboratory data of seated reach with consideration of the subjective difficulty ratings, the method of modeling reach envelopes is studied based on spherical harmonics. The surface fitting using spherical harmonics is conducted for circumstances both with and without seat adjustments. For use with adjustable seat, the seating position model is introduced to re-locate the test data. The surface fitting is conducted for both population and individual reach envelopes, as well as for boundary envelopes. Comparison of the envelopes of adjustable seat and the SAE J287 control reach envelope shows that the latter is nearly at the middle difficulty level. It is also found that the abilities of reach envelope models in expressing the shape of the reach limits based on spherical harmonics depends both on the terms in the model expression and on the data used to fit the envelope surfaces. Copyright © 2016 Elsevier Ltd. All rights reserved.

Thermal Insulating Concrete Wall Panel Design for Sustainable Built Environment

PubMed Central

Zhou, Ao; Wong, Kwun-Wah

2014-01-01

Air-conditioning system plays a significant role in providing users a thermally comfortable indoor environment, which is a necessity in modern buildings. In order to save the vast energy consumed by air-conditioning system, the building envelopes in envelope-load dominated buildings should be well designed such that the unwanted heat gain and loss with environment can be minimized. In this paper, a new design of concrete wall panel that enhances thermal insulation of buildings by adding a gypsum layer inside concrete is presented. Experiments have been conducted for monitoring the temperature variation in both proposed sandwich wall panel and conventional concrete wall panel under a heat radiation source. For further understanding the thermal effect of such sandwich wall panel design from building scale, two three-story building models adopting different wall panel designs are constructed for evaluating the temperature distribution of entire buildings using finite element method. Both the experimental and simulation results have shown that the gypsum layer improves the thermal insulation performance by retarding the heat transfer across the building envelopes. PMID:25177718

Thermal insulating concrete wall panel design for sustainable built environment.

PubMed

Zhou, Ao; Wong, Kwun-Wah; Lau, Denvid

2014-01-01

Air-conditioning system plays a significant role in providing users a thermally comfortable indoor environment, which is a necessity in modern buildings. In order to save the vast energy consumed by air-conditioning system, the building envelopes in envelope-load dominated buildings should be well designed such that the unwanted heat gain and loss with environment can be minimized. In this paper, a new design of concrete wall panel that enhances thermal insulation of buildings by adding a gypsum layer inside concrete is presented. Experiments have been conducted for monitoring the temperature variation in both proposed sandwich wall panel and conventional concrete wall panel under a heat radiation source. For further understanding the thermal effect of such sandwich wall panel design from building scale, two three-story building models adopting different wall panel designs are constructed for evaluating the temperature distribution of entire buildings using finite element method. Both the experimental and simulation results have shown that the gypsum layer improves the thermal insulation performance by retarding the heat transfer across the building envelopes.

Technical- and environmental-efficiency analysis of irrigated cotton-cropping systems in Punjab, Pakistan using data envelopment analysis.

PubMed

Ullah, Asmat; Perret, Sylvain R

2014-08-01

Cotton cropping in Pakistan uses substantial quantities of resources and adversely affects the environment with pollutants from the inputs, particularly pesticides. A question remains regarding to what extent the reduction of such environmental impact is possible without compromising the farmers' income. This paper investigates the environmental, technical, and economic performances of selected irrigated cotton-cropping systems in Punjab to quantify the sustainability of cotton farming and reveal options for improvement. Using mostly primary data, our study quantifies the technical, cost, and environmental efficiencies of different farm sizes. A set of indicators has been computed to reflect these three domains of efficiency using the data envelopment analysis technique. The results indicate that farmers are broadly environmentally inefficient; which primarily results from poor technical inefficiency. Based on an improved input mix, the average potential environmental impact reduction for small, medium, and large farms is 9, 13, and 11 %, respectively, without compromising the economic return. Moreover, the differences in technical, cost, and environmental efficiencies between small and medium and small and large farm sizes were statistically significant. The second-stage regression analysis identifies that the entire farm size significantly affects the efficiencies, whereas exposure to extension and training has positive effects, and the sowing methods significantly affect the technical and environmental efficiencies. Paradoxically, the formal education level is determined to affect the efficiencies negatively. This paper discusses policy interventions that can improve the technical efficiency to ultimately increase the environmental efficiency and reduce the farmers' operating costs.

Tone signal generator for producing multioperator tone signals using an operator circuit including a waveform generator, a selector and an enveloper

DOEpatents

Dong, Q.; Jenkins, M.V.; Bernadas, S.R.

1997-09-09

A frequency modulation (FM) tone signal generator for generating a FM tone signal is disclosed. The tone signal generator includes a waveform generator having a plurality of wave tables, a selector and an enveloper. The waveform generator furnishes a waveform signal in response to a phase angle address signal. Each wave table stores a different waveform. The selector selects one of the wave tables in response to a plurality of selection signals such that the selected wave table largely provides the waveform signal upon being addressed largely by the phase angle address signal. Selection of the selected wave table varies with each selection signal. The enveloper impresses an envelope signal on the waveform signal. The envelope signal is used as a carrier or modulator for generating the FM tone signal. 17 figs.

Genetic control of T cell responsiveness to the Friend murine leukemia virus envelope antigen. Identification of class II loci of the H-2 as immune response genes

PubMed Central

1988-01-01

T cells primed specifically for the envelope glycoprotein of Friend murine leukemia helper virus (F-MuLV) were prepared by immunizing mice with a recombinant vaccinia virus that expressed the entire env gene of F-MuLV. Significant proliferative responses of F-MuLV envelope- specific, H-2a/b T cells were observed when the T cells were stimulated with antigen-pulsed peritoneal exudate cells (PEC) having the b allele at the K, A beta, A alpha, and E beta loci of the H-2. On the other hand, PEC having only the kappa allele at these loci did not induce the envelope-specific T cell proliferation, even when the PEC had the b allele at the E alpha, S, or D loci. F-MuLV envelope-specific proliferation of H-2a/b T cells under the stimulation of antigen- pulsed, H-2a/b PEC was specifically blocked with anti-I-Ab and anti-I- Ek mAbs but not with anti-Kb, anti-Kk, or anti-I-Ak mAbs. Moreover, (B10.MBR x A/WySn)F1 mice that have the b allele only at the K locus but not in I-A subregion were nonresponders to the envelope glycoprotein, and the bm12 mutation at the A beta locus completely abolished the T cell responsiveness to this antigen. These results indicate that proliferative T cells recognize a limited number of epitopes on F-MuLV envelope protein in the context of I-Ab, hybrid I- Ak/b, and/or hybrid I-Ek/b class II MHC molecules but fail to recognize the same envelope protein in the context of I-Ak or I-Ek molecules. This influence of the H-2I region on T cell recognition of the envelope glycoprotein appeared to control in vivo induction of protective immunity against Friend virus complex after immunization with the vaccinia-F-MuLV env vaccine. Thus, these results provide, for the first time, direct evidence for Ir gene-controlled responder/nonresponder phenotypes influencing the immune response to a pathogenic virus of mice. PMID:3141552

Anticipatory control: A software retrofit for current plant controllers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parthasarathy, S.; Parlos, A.G.; Atiya, A.F.

1993-01-01

The design and simulated testing of an artificial neural network (ANN)-based self-adapting controller for complex process systems are presented in this paper. The proposed controller employs concepts based on anticipatory systems, which have been widely used in the petroleum and chemical industries, and they are slowly finding their way into the power industry. In particular, model predictive control (MPC) is used for the systematic adaptation of the controller parameters to achieve desirable plant performance over the entire operating envelope. The versatile anticipatory control algorithm developed in this study is projected to enhance plant performance and lend robustness to drifts inmore » plant parameters and to modeling uncertainties. This novel technique of integrating recurrent ANNs with a conventional controller structure appears capable of controlling complex, nonlinear, and nonminimum phase process systems. The direct, on-line adaptive control algorithm presented in this paper considers the plant response over a finite time horizon, diminishing the need for manual control or process interruption for controller gain tuning.« less

3D multifunctional integumentary membranes for spatiotemporal cardiac measurements and stimulation across the entire epicardium

NASA Astrophysics Data System (ADS)

Xu, Lizhi; Gutbrod, Sarah R.; Bonifas, Andrew P.; Su, Yewang; Sulkin, Matthew S.; Lu, Nanshu; Chung, Hyun-Joong; Jang, Kyung-In; Liu, Zhuangjian; Ying, Ming; Lu, Chi; Webb, R. Chad; Kim, Jong-Seon; Laughner, Jacob I.; Cheng, Huanyu; Liu, Yuhao; Ameen, Abid; Jeong, Jae-Woong; Kim, Gwang-Tae; Huang, Yonggang; Efimov, Igor R.; Rogers, John A.

2014-02-01

Means for high-density multiparametric physiological mapping and stimulation are critically important in both basic and clinical cardiology. Current conformal electronic systems are essentially 2D sheets, which cannot cover the full epicardial surface or maintain reliable contact for chronic use without sutures or adhesives. Here we create 3D elastic membranes shaped precisely to match the epicardium of the heart via the use of 3D printing, as a platform for deformable arrays of multifunctional sensors, electronic and optoelectronic components. Such integumentary devices completely envelop the heart, in a form-fitting manner, and possess inherent elasticity, providing a mechanically stable biotic/abiotic interface during normal cardiac cycles. Component examples range from actuators for electrical, thermal and optical stimulation, to sensors for pH, temperature and mechanical strain. The semiconductor materials include silicon, gallium arsenide and gallium nitride, co-integrated with metals, metal oxides and polymers, to provide these and other operational capabilities. Ex vivo physiological experiments demonstrate various functions and methodological possibilities for cardiac research and therapy.

Low-Altitude Exploration of the Venus Atmosphere by Balloon

NASA Technical Reports Server (NTRS)

Landis, Geoffrey A.

2010-01-01

The planet Venus represents an exciting target for future exploration by spacecraft. One target of scientific interest is the lower atmosphere, which represents an environment of high temperature and moderate to high atmospheric pressure. This represents a considerable challenge to the technical art of ballooning, but one which may be amenable to solution. Several possible designs for low-altitude balloons are discussed. Conceptual design for three mission examples are analyzed: a conventional balloon operating below the cloud level at an altitude of 25 kilometers, a large rigid-envelope balloon operating near the surface at an altitude of 5 kilometers, and a small, technology demonstrator rigid-envelope balloon operating at 5 kilometers.

An Experimental Study of Cavitation Detection in a Centrifugal Pump Using Envelope Analysis

NASA Astrophysics Data System (ADS)

Tan, Chek Zin; Leong, M. Salman

Cavitation represents one of the most common faults in pumps and could potentially lead to a series of failure in mechanical seal, impeller, bearing, shaft, motor, etc. In this work, an experimental rig was setup to investigate cavitation detection using vibration envelope analysis method, and measured parameters included sound, pressure and flow rate for feasibility of cavitation detection. The experiment testing included 3 operating points of the centrifugal pump (B.E.P, 90% of B.E.P and 80% of B.E.P). Suction pressure of the centrifugal pump was decreased gradually until the inception point of cavitation. Vibration measurements were undertaken at various locations including casing, bearing, suction and discharge flange of the centrifugal pump. Comparisons of envelope spectrums under cavitating and non-cavitating conditions were presented. Envelope analysis was proven useful in detecting cavitation over the 3 testing conditions. During the normal operating condition, vibration peak synchronous to rotational speed was more pronounced. It was however during cavitation condition, the half order sub-harmonic vibration component was clearly evident in the envelope spectrums undertaken at all measurement locations except at the pump bearing. The possible explanation of the strong sub-harmonic (½ of BPF) during cavitation existence in the centrifugal pump was due to insufficient time for the bubbles to collapse completely before the end of the single cycle.

Stability and Controls Analysis and Flight Test Results of a 24-Foot Telescoping Nose Boom on an F-15B Airplane

NASA Technical Reports Server (NTRS)

Moua, Cheng M.; Cox, Timothy H.; McWherter, Shaun C.

2008-01-01

The Quiet Spike(TradeMark) F-15B flight research program investigated supersonic shock reduction using a 24-ft telescoping nose boom on an F-15B airplane. The program goal was to collect flight data for model validation up to 1.8 Mach. In the area of stability and controls, the primary concerns were to assess the potential destabilizing effect of the oversized nose boom on the stability, controllability, and handling qualities of the airplane and to ensure adequate stability margins across the entire research flight envelope. This paper reports on the stability and control analytical methods, flight envelope clearance approach, and flight test results of the F-15B telescoping nose boom configuration. Also discussed are brief pilot commentary on typical piloting tasks and refueling tasks.

Refinement of Optimal Work Envelope for Extra-Vehicular Activity (EVA) Suit Operations

NASA Technical Reports Server (NTRS)

Jaramillo, Marcos A.; Angermiller, Bonnie L.; Morency, Richard M.; Rajululu, Sudhakar L.

2008-01-01

The purpose of the Extravehicular Mobility Unit (EMU) Work Envelope study is to determine and revise the work envelope defined in NSTS 07700 "System Description and Design Data - Extravehicular Activities" [1], arising from an action item as a result of the Shoulder Injury Tiger Team findings. The aim of this study is to determine a common work envelope that will encompass a majority of the crew population while minimizing the possibility of shoulder and upper arm injuries. There will be approximately two phases of testing: arm sweep analysis to be performed in the Anthropometry and Biomechanics Facility (ABF), and torso lean testing to be performed on the Precision Air Bearing Facility (PABF). NSTS 07700 defines the preferred work envelope arm reach in terms of maximum reach, and defines the preferred work envelope torso flexibility of a crewmember to be a net 45 degree backwards lean [1]. This test served two functions: to investigate the validity of the standard discussed in NSTS 07700, and to provide recommendations to update this standard if necessary.

Purging means and method for Xenon arc lamps

NASA Technical Reports Server (NTRS)

Miller, C. G. (Inventor)

1973-01-01

High pressure Xenon short-arc lamp with two reservoirs which are selectively connectable to the lamp's envelope is described. One reservoir contains an absorbent which will absorb both Xenon and contaminant gases such as CO2 and O2. The absorbent temperature is controlled to evacuate the envelope of both the Xenon and the contaminant gases. The temperature of the absorbent is then raised to desorb only clean Xenon while retaining the contaminant gases, thereby clearing the envelope of the contaminant gases. The second reservoir contains a gas whose specific purpose is, to remove the objectional metal film which deposits gradually on the interior surface of the lamp envelope during normal arc operation. The origin of the film is metal transferred from the cathode of the arc lamp by sputtering or other gas transfer processes.

Influence of two different flap designs on the sequelae of mandibular third molar surgery.

PubMed

Erdogan, Ozgür; Tatlı, Ufuk; Ustün, Yakup; Damlar, Ibrahim

2011-09-01

The aim of this study was to compare the influence of triangular and envelope flaps on trismus, pain, and facial swelling after mandibular third molar surgery. Twenty healthy patients with bilateral, symmetrically impacted mandibular third molars were included in this double-blinded, prospective, cross-over, randomized study. The patients were operated with envelope flap on one side and triangular flap on the other side. Trismus was determined by measuring maximum interincisal opening, and facial swelling was evaluated using a tape measuring method. Pain was determined using visual analog scale (VAS) and recording the number of pain pills taken. The facial swelling measurements and VAS scores were lower in the envelope flap group compared to the triangular flap group. There was no significant difference between the two flap designs in operation time, maximum interincisal opening, and the number of analgesics taken. Envelope flap yields to less facial swelling and reduced VAS scores in comparison to triangular flap. There is no clinical difference in trismus between the two flap designs. Despite the higher VAS scores with triangular flap, no additional doses of analgesics were required in triangular flap.

Investigating TiC as the carrier of the 21-micron feature: HD 56126

NASA Astrophysics Data System (ADS)

Zalucha, A.; Meixner, M.; Fong, D.; Justtanont, K.; Ueta, T.

2003-12-01

A sub-class of proto-planetary nebulae (PPNs) are characterized by an unidentified infrared feature at 21 microns and have been dubbed the 21-micron PPNs. HD 56126 (a.k.a. IRAS 07134+1005) is one of the best studied 21-micron PPNs. Von Helden et al. have proposed nanocrystals of titanium carbide (TiC) to be the carrier of the 21-micron feature. However in order to create TiC, high densities are required in the circumstellar environment, meaning high mass loss rates on the order of 10-3 Msun yr-1. This value suggests that the entire circumstellar envelope was created in a singular catastrophic mass loss event. Here a detailed analysis is presented of the molecular envelope using BIMA data and of the dust envelope using the 2-Dust radiative transfer code to model dust images and the spectral energy distribution. Qualitative results from the BIMA channel maps reveal a molecular envelope expanding away from the star at 10 km s-1. The observations resolve a depression at the center of the envelope in the channels 67, 69, and 71 km s-1. The structure observed in the 67 km s-1 channel map bears a resemblance to the optical and mid-infrared images of HD 56126. However, the outer radius of the CO emission, 10'', is significantly larger than the mid-IR and optical emission. Assuming a distance of 3 kpc, this outer radius corresponds to a distance of 4.5 x 1017 cm and a time scale of 1.4 x 104 years. The size of this CO shell contradicts the catastrophic mass loss event required by von Helden et al.

Integrated gas turbine engine-nacelle

NASA Technical Reports Server (NTRS)

Adamson, A. P.; Sargisson, D. F.; Stotler, C. L., Jr. (Inventor)

1979-01-01

A nacelle for use with a gas turbine engine is provided with an integral webbed structure resembling a spoked wheel for rigidly interconnecting the nacelle and engine. The nacelle is entirely supported in its spacial relationship with the engine by means of the webbed structure. The inner surface of the nacelle defines the outer limits of the engine motive fluid flow annulus, while the outer surface of the nacelle defines a streamlined envelope for the engine.

Identifying On-Orbit Test Targets for Space Fence Operational Testing

NASA Astrophysics Data System (ADS)

Pechkis, D.; Pacheco, N.; Botting, T.

2014-09-01

Space Fence will be an integrated system of two ground-based, S-band (2 to 4 GHz) phased-array radars located in Kwajalein and perhaps Western Australia [1]. Space Fence will cooperate with other Space Surveillance Network sensors to provide space object tracking and radar characterization data to support U.S. Strategic Command space object catalog maintenance and other space situational awareness needs. We present a rigorous statistical test design intended to test Space Fence to the letter of the program requirements as well as to characterize the system performance across the entire operational envelope. The design uses altitude, size, and inclination as independent factors in statistical tests of dependent variables (e.g., observation accuracy) linked to requirements. The analysis derives the type and number of necessary test targets. Comparing the resulting sample sizes with the number of currently known targets, we identify those areas where modelling and simulation methods are needed. Assuming hypothetical Kwajalein radar coverage and a conservative number of radar passes per object per day, we conclude that tests involving real-world space objects should take no more than 25 days to evaluate all operational requirements; almost 60 percent of the requirements can be tested in a single day and nearly 90 percent can be tested in one week or less. Reference: [1] L. Haines and P. Phu, Space Fence PDR Concept Development Phase, 2011 AMOS Conference Technical Papers.

Envelope Protein Palmitoylations Are Crucial for Murine Coronavirus Assembly▿

PubMed Central

Boscarino, Joseph A.; Logan, Hillary L.; Lacny, Jason J.; Gallagher, Thomas M.

2008-01-01

The coronavirus assembly process encloses a ribonucleoprotein genome into vesicles containing the lipid-embedded proteins S (spike), E (envelope), and M (membrane). This process depends on interactions with membranes that may involve palmitoylation, a common posttranslational lipidation of cysteine residues. To determine whether specific palmitoylations influence coronavirus assembly, we introduced plasmid DNAs encoding mouse hepatitis coronavirus (MHV) S, E, M, and N (nucleocapsid) into 293T cells and found that virus-like particles (VLPs) were robustly assembled and secreted into culture medium. Palmitate adducts predicted on cysteines 40, 44, and 47 of the 83-residue E protein were then evaluated by constructing mutant cDNAs with alanine or glycine codon substitutions at one or more of these positions. Triple-substituted proteins (E.Ts) lacked palmitate adducts. Both native E and E.T proteins localized at identical perinuclear locations, and both copurified with M proteins, but E.T was entirely incompetent for VLP production. In the presence of the E.T proteins, the M protein subunits accumulated into detergent-insoluble complexes that failed to secrete from cells, while native E proteins mobilized M into detergent-soluble secreted forms. Many of these observations were corroborated in the context of natural MHV infections, with native E, but not E.T, complementing debilitated recombinant MHVs lacking E. Our findings suggest that palmitoylations are essential for E to act as a vesicle morphogenetic protein and further argue that palmitoylated E proteins operate by allowing the primary coronavirus assembly subunits to assume configurations that can mobilize into secreted lipid vesicles and virions. PMID:18184706

Evolution of Space Shuttle Range Safety (RS) Ascent Flight Envelope Design

NASA Technical Reports Server (NTRS)

Brewer, Joan D.

2011-01-01

Ascent flight envelopes are trajectories that define the normal operating region of a space vehicle s position from liftoff until the end of powered flight. They fulfill part of the RS data requirements imposed by the Air Force s 45th Space Wing (45SW) on space vehicles launching from the Eastern Range (ER) in Florida. The 45SW is chartered to protect the public by minimizing risks associated with the inherent hazards of launching a vehicle into space. NASA s Space Shuttle program has launched 130+ manned missions over a 30 year period from the ER. Ascent envelopes were delivered for each of those missions. The 45SW envelope requirements have remained largely unchanged during this time. However, the methodology and design processes used to generate the envelopes have evolved over the years to support mission changes, maintain high data quality, and reduce costs. The evolution of the Shuttle envelope design has yielded lessons learned that can be applied to future endevours. There have been numerous Shuttle ascent design enhancements over the years that have caused the envelope methodology to evolve. One of these Shuttle improvements was the introduction of onboard flight software changes implemented to improve launch probability. This change impacted the preflight nominal ascent trajectory, which is a key element in the RS envelope design. While the early Shuttle nominal trajectories were designed preflight using a representative monthly mean wind, the new software changes involved designing a nominal ascent trajectory on launch day using real-time winds. Because the actual nominal trajectory position was not known until launch day, the envelope analysis had to be customized to account for this nominal trajectory variation in addition to the other envelope components.

Kid-mediated chromosome compaction ensures proper nuclear envelope formation.

PubMed

Ohsugi, Miho; Adachi, Kenjiro; Horai, Reiko; Kakuta, Shigeru; Sudo, Katsuko; Kotaki, Hayato; Tokai-Nishizumi, Noriko; Sagara, Hiroshi; Iwakura, Yoichiro; Yamamoto, Tadashi

2008-03-07

Toward the end of mitosis, neighboring chromosomes gather closely to form a compact cluster. This is important for reassembling the nuclear envelope around the entire chromosome mass but not individual chromosomes. By analyzing mice and cultured cells lacking the expression of chromokinesin Kid/kinesin-10, we show that Kid localizes to the boundaries of anaphase and telophase chromosomes and contributes to the shortening of the anaphase chromosome mass along the spindle axis. Loss of Kid-mediated anaphase chromosome compaction often causes the formation of multinucleated cells, specifically at oocyte meiosis II and the first couple of mitoses leading to embryonic death. In contrast, neither male meiosis nor somatic mitosis after the morula-stage is affected by Kid deficiency. These data suggest that Kid-mediated anaphase/telophase chromosome compaction prevents formation of multinucleated cells. This protection is especially important during the very early stages of development, when the embryonic cells are rich in ooplasm.

An indirect method for numerical optimization using the Kreisselmeir-Steinhauser function

NASA Technical Reports Server (NTRS)

Wrenn, Gregory A.

1989-01-01

A technique is described for converting a constrained optimization problem into an unconstrained problem. The technique transforms one of more objective functions into reduced objective functions, which are analogous to goal constraints used in the goal programming method. These reduced objective functions are appended to the set of constraints and an envelope of the entire function set is computed using the Kreisselmeir-Steinhauser function. This envelope function is then searched for an unconstrained minimum. The technique may be categorized as a SUMT algorithm. Advantages of this approach are the use of unconstrained optimization methods to find a constrained minimum without the draw down factor typical of penalty function methods, and that the technique may be started from the feasible or infeasible design space. In multiobjective applications, the approach has the advantage of locating a compromise minimum design without the need to optimize for each individual objective function separately.

A Study of Mechanisms Producing Astrophysical Jets.

DTIC Science & Technology

1988-03-01

REPORT NUMBER(S) IS0001f A FAL- T R-88-007 6a. NAME OF PERFORMING ORGANIZATION 6b. OFFICE SYMBOL 7a. NAME OF MONITORING ORGANIZATION (if applicable...entire rest energy by some , ,, . , , , - , . , . ,4 . ,... .- t . mechanism or other. If matter is in-falling in this fashion, conservation of angular...they are still enveloped in the dense gas and dust from which they are condensing. Associated with a class of these stars, the T Tauri stars, are

International Standard Payload Rack volume

NASA Technical Reports Server (NTRS)

2001-01-01

Outer dimensions of the International Standard Payload Rack (ISPR) that will be used on the International Space Station (ISS) sets the envelope for scientists designing hardware for experiments in biological and physical sciences aboard ISS. The ISPR includes attachments to ISS utilities (electrical power, heating and cooling, data, fluids, vacuum, etc.) through standoffs that hold the racks in place in the lab modules. Usage will range from facilities that take entire racks to specialized drawers occupying a portion of a rack.

Duck egg-drop syndrome caused by BYD virus, a new Tembusu-related flavivirus.

PubMed

Su, Jingliang; Li, Shuang; Hu, Xudong; Yu, Xiuling; Wang, Yongyue; Liu, Peipei; Lu, Xishan; Zhang, Guozhong; Hu, Xueying; Liu, Di; Li, Xiaoxia; Su, Wenliang; Lu, Hao; Mok, Ngai Shing; Wang, Peiyi; Wang, Ming; Tian, Kegong; Gao, George F

2011-03-24

Since April 2010, a severe outbreak of duck viral infection, with egg drop, feed uptake decline and ovary-oviduct disease, has spread around the major duck-producing regions in China. A new virus, named BYD virus, was isolated in different areas, and a similar disease was reproduced in healthy egg-producing ducks, infecting with the isolated virus. The virus was re-isolated from the affected ducks and replicated well in primary duck embryo fibroblasts and Vero cells, causing the cytopathic effect. The virus was identified as an enveloped positive-stranded RNA virus with a size of approximately 55 nm in diameter. Genomic sequencing of the isolated virus revealed that it is closely related to Tembusu virus (a mosquito-borne Ntaya group flavivirus), with 87-91% nucleotide identity of the partial E (envelope) proteins to that of Tembusu virus and 72% of the entire genome coding sequence with Bagaza virus, the most closely related flavivirus with an entirely sequenced genome. Collectively our systematic studies fulfill Koch's postulates, and therefore, the causative agent of the duck egg drop syndrome occurring in China is a new flavivirus. Flavivirus is an emerging and re-emerging zoonotic pathogen and BYD virus that causes severe egg-drop, could be disastrous for the duck industry. More importantly its public health concerns should also be evaluated, and its epidemiology should be closely watched due to the zoonotic nature of flaviviruses.

Precise and long-term stabilization of the carrier-envelope phase of femtosecond laser pulses using an enhanced direct locking technique.

PubMed

Yu, Tae Jun; Hong, Kyung-Han; Choi, Hyun-Gyug; Sung, Jae Hee; Choi, Il Woo; Ko, Do-Kyeong; Lee, Jongmin; Kim, Junwon; Kim, Dong Eon; Nam, Chang Hee

2007-06-25

We demonstrate a long-term operation with reduced phase noise in the carrier-envelope-phase (CEP) stabilization process by employing a double feedback loop and an improved signal detection in the direct locking technique [Opt. Express 13, 2969 (2005)]. A homodyne balanced detection method is employed for efficiently suppressing the dc noise in the f-2f beat signal, which is converted into the CEP noise in the direct locking loop working at around zero carrier-envelope offset frequency (f(ceo)). In order to enhance the long-term stability, we have used the double feedback scheme that modulates both the oscillator pump power for a fast control and the intracavity-prism insertion depth for a slow and high-dynamic-range control. As a result, the in-loop phase jitter is reduced from 50 mrad of the previous result to 29 mrad, corresponding to 13 as in time scale, and the long-term stable operation is achieved for more than 12 hours.

Increasing Slew Performance of Reaction Wheel Attitude Control Systems

DTIC Science & Technology

2013-09-01

vectors in any arbitrary direction creates the momentum envelope (Chapter IV). The shape of the reaction wheel momentum envelope is a polyhedron [15...performance. This procedural limitation further reduces the operable reaction wheel momentum space polyhedron to the largest inscribed sphere, which...respective plane. These minima are also the global minima, each marked in magenta. The four-wheel polyhedron is again shown in three orthogonal views in

Evaluation of the Fretting Resistance of the High Voltage Insulation on the ITER Magnet Feeder Busbars

NASA Astrophysics Data System (ADS)

Clayton, N.; Crouchen, M.; Evans, D.; Gung, C.-Y.; Su, M.; Devred, A.; Piccin, R.

2017-12-01

The high voltage (HV) insulation on the ITER magnet feeder superconducting busbars and current leads will be prepared from S-glass fabric, pre-impregnated with an epoxy resin, which is interleaved with polyimide film and wrapped onto the components and cured during feeder manufacture. The insulation architecture consists of nine half-lapped layers of glass/Kapton, which is then enveloped in a ground-screen, and two further half-lapped layers of glass pre-preg for mechanical protection. The integrity of the HV insulation is critical in order to inhibit electrical arcs within the feeders. The insulation over the entire length of the HV components (bus bar, current leads and joints) must provide a level of voltage isolation of 30 kV. In operation, the insulation on ITER busbars will be subjected to high mechanical loads, arising from Lorentz forces, and in addition will be subjected to fretting erosion against stainless steel clamps, as the pulsed nature of some magnets results in longitudinal movement of the busbar. This work was aimed at assessing the wear on, and the changes in, the electrical properties of the insulation when subjected to typical ITER operating conditions. High voltage tests demonstrated that the electrical isolation of the insulation was intact after the fretting test.

Initial Evaluations of LoC Prediction Algorithms Using the NASA Vertical Motion Simulator

NASA Technical Reports Server (NTRS)

Krishnakumar, Kalmanje; Stepanyan, Vahram; Barlow, Jonathan; Hardy, Gordon; Dorais, Greg; Poolla, Chaitanya; Reardon, Scott; Soloway, Donald

2014-01-01

Flying near the edge of the safe operating envelope is an inherently unsafe proposition. Edge of the envelope here implies that small changes or disturbances in system state or system dynamics can take the system out of the safe envelope in a short time and could result in loss-of-control events. This study evaluated approaches to predicting loss-of-control safety margins as the aircraft gets closer to the edge of the safe operating envelope. The goal of the approach is to provide the pilot aural, visual, and tactile cues focused on maintaining the pilot's control action within predicted loss-of-control boundaries. Our predictive architecture combines quantitative loss-of-control boundaries, an adaptive prediction method to estimate in real-time Markov model parameters and associated stability margins, and a real-time data-based predictive control margins estimation algorithm. The combined architecture is applied to a nonlinear transport class aircraft. Evaluations of various feedback cues using both test and commercial pilots in the NASA Ames Vertical Motion-base Simulator (VMS) were conducted in the summer of 2013. The paper presents results of this evaluation focused on effectiveness of these approaches and the cues in preventing the pilots from entering a loss-of-control event.

Control Design for an Advanced Geared Turbofan Engine

NASA Technical Reports Server (NTRS)

Chapman, Jeffryes W.; Litt, Jonathan S.

2017-01-01

This paper describes the design process for the control system of an advanced geared turbofan engine. This process is applied to a simulation that is representative of a 30,000 lbf thrust class concept engine with two main spools, ultra-high bypass ratio, and a variable area fan nozzle. Control system requirements constrain the non-linear engine model as it operates throughout its flight envelope of sea level to 40,000 ft and from 0 to 0.8 Mach. The control architecture selected for this project was developed from literature and reflects a configuration that utilizes a proportional integral controller integrated with sets of limiters that enable the engine to operate safely throughout its flight envelope. Simulation results show the overall system meets performance requirements without exceeding system operational limits.

Measuring the Capacity Utilization of Public District Hospitals in Tunisia: Using Dual Data Envelopment Analysis Approach

PubMed Central

Arfa, Chokri; Leleu, Hervé; Goaïed, Mohamed; van Mosseveld, Cornelis

2017-01-01

Background: Public district hospitals (PDHs) in Tunisia are not operating at full plant capacity and underutilize their operating budget. Methods: Individual PDHs capacity utilization (CU) is measured for 2000 and 2010 using dual data envelopment analysis (DEA) approach with shadow prices input and output restrictions. The CU is estimated for 101 of 105 PDH in 2000 and 94 of 105 PDH in 2010. Results: In average, unused capacity is estimated at 18% in 2010 vs. 13% in 2000. Of PDHs 26% underutilize their operating budget in 2010 vs. 21% in 2000. Conclusion: Inadequate supply, health quality and the lack of operating budget should be tackled to reduce unmet user’s needs and the bypassing of the PDHs and, thus to increase their CU. Social health insurance should be turned into a direct purchaser of curative and preventive care for the PDHs. PMID:28005538

Neural network based automatic limit prediction and avoidance system and method

NASA Technical Reports Server (NTRS)

Calise, Anthony J. (Inventor); Prasad, Jonnalagadda V. R. (Inventor); Horn, Joseph F. (Inventor)

2001-01-01

A method for performance envelope boundary cueing for a vehicle control system comprises the steps of formulating a prediction system for a neural network and training the neural network to predict values of limited parameters as a function of current control positions and current vehicle operating conditions. The method further comprises the steps of applying the neural network to the control system of the vehicle, where the vehicle has capability for measuring current control positions and current vehicle operating conditions. The neural network generates a map of current control positions and vehicle operating conditions versus the limited parameters in a pre-determined vehicle operating condition. The method estimates critical control deflections from the current control positions required to drive the vehicle to a performance envelope boundary. Finally, the method comprises the steps of communicating the critical control deflection to the vehicle control system; and driving the vehicle control system to provide a tactile cue to an operator of the vehicle as the control positions approach the critical control deflections.

Object Classification Based on Analysis of Spectral Characteristics of Seismic Signal Envelopes

NASA Astrophysics Data System (ADS)

Morozov, Yu. V.; Spektor, A. A.

2017-11-01

A method for classifying moving objects having a seismic effect on the ground surface is proposed which is based on statistical analysis of the envelopes of received signals. The values of the components of the amplitude spectrum of the envelopes obtained applying Hilbert and Fourier transforms are used as classification criteria. Examples illustrating the statistical properties of spectra and the operation of the seismic classifier are given for an ensemble of objects of four classes (person, group of people, large animal, vehicle). It is shown that the computational procedures for processing seismic signals are quite simple and can therefore be used in real-time systems with modest requirements for computational resources.

Binaries discovered by the SPY survey. VI. Discovery of a low mass companion to the hot subluminous planetary nebula central star EGB 5 - a recently ejected common envelope?

NASA Astrophysics Data System (ADS)

Geier, S.; Napiwotzki, R.; Heber, U.; Nelemans, G.

2011-04-01

Hot subdwarf B stars (sdBs) in close binary systems are assumed to be formed via common envelope ejection. According to theoretical models, the amount of energy and angular momentum deposited in the common envelope scales with the mass of the companion. That low mass companions near or below the core hydrogen-burning limit are able to trigger the ejection of this envelope is well known. The currently known systems have very short periods ≃0.1-0.3 d. Here we report the discovery of a low mass companion (M2 > 0.14 M⊙) orbiting the sdB star and central star of a planetary nebula EGB 5 with an orbital period of 16.5 d at a minimum separation of 23 R⊙. Its long period is only just consistent with the energy balance prescription of the common envelope. The marked difference between the short and long period systems will provide strong constraints on the common envelope phase, in particular if the masses of the sdB stars can be measured accurately. Due to selection effects, the fraction of sdBs with low mass companions and similar or longer periods may be quite high. Low mass stellar and substellar companions may therefore play a significant role for the still unclear formation of hot subdwarf stars. Furthermore, the nebula around EGB 5 may be the remnant of the ejected common envelope making this binary a unique system to study this short und poorly understood phase of binary evolution. Based on observations at the Paranal Observatory of the European Southern Observatory for programmes No. 167.H-0407(A) and 71.D-0383(A). Based on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Max-Planck Institut für Astronomie and the Instituto de Astrofísica de Andalucía (CSIC). Some of the data used in this work were obtained at the William Herschel Telescope (WHT) operated by the Isaac Newton Group of Telescopes (ING).

tirant, a newly discovered active endogenous retrovirus in Drosophila simulans.

PubMed

Akkouche, Abdou; Rebollo, Rita; Burlet, Nelly; Esnault, Caroline; Martinez, Sonia; Viginier, Barbara; Terzian, Christophe; Vieira, Cristina; Fablet, Marie

2012-04-01

Endogenous retroviruses have the ability to become permanently integrated into the genomes of their host, and they are generally transmitted vertically from parent to progeny. With the exception of gypsy, few endogenous retroviruses have been identified in insects. In this study, we describe the tirant endogenous retrovirus in a subset of Drosophila simulans natural populations. By focusing on the envelope gene, we show that the entire retroviral cycle (transcription, translation, and retrotransposition) can be completed for tirant within one population of this species.

Multi-Fault Detection of Rolling Element Bearings under Harsh Working Condition Using IMF-Based Adaptive Envelope Order Analysis

PubMed Central

Zhao, Ming; Lin, Jing; Xu, Xiaoqiang; Li, Xuejun

2014-01-01

When operating under harsh condition (e.g., time-varying speed and load, large shocks), the vibration signals of rolling element bearings are always manifested as low signal noise ratio, non-stationary statistical parameters, which cause difficulties for current diagnostic methods. As such, an IMF-based adaptive envelope order analysis (IMF-AEOA) is proposed for bearing fault detection under such conditions. This approach is established through combining the ensemble empirical mode decomposition (EEMD), envelope order tracking and fault sensitive analysis. In this scheme, EEMD provides an effective way to adaptively decompose the raw vibration signal into IMFs with different frequency bands. The envelope order tracking is further employed to transform the envelope of each IMF to angular domain to eliminate the spectral smearing induced by speed variation, which makes the bearing characteristic frequencies more clear and discernible in the envelope order spectrum. Finally, a fault sensitive matrix is established to select the optimal IMF containing the richest diagnostic information for final decision making. The effectiveness of IMF-AEOA is validated by simulated signal and experimental data from locomotive bearings. The result shows that IMF-AEOA could accurately identify both single and multiple faults of bearing even under time-varying rotating speed and large extraneous shocks. PMID:25353982

Stress path dependent hydromechanical behaviour of heterogeneous carbonate rock

NASA Astrophysics Data System (ADS)

Gland, N.; Dautriat, J.; Dimanov, A.; Raphanel, J.

2010-06-01

The influence of stress paths, representative of reservoir conditions, on the hydromechanical behavior of a moderately heterogeneous carbonate has been investigated. Multiscale structural heterogeneities, common for instance in carbonate rocks, can strongly alter the mechanical response and significantly influence the evolution of flow properties with stress. Using a triaxial cell, the permeability evolutions during compression and the effects of brittle (fracture) and plastic (pore collapse) deformations at yield, were measured. A strong scattering was observed on the mechanical response both in term of compressibility and failure threshold. Using the porosity scaling predicted by an adapted effective medium theory (based on crack growth under Hertzian contact), we have rescaled the critical pressures by the normalized porosity deviation. This procedure reduces efficiently the scattering, revealing in the framework of proportional stress path loading, a linear relation between the critical pressures and the stress path parameter through all the deformation regimes. It leads to a new formulation for the critical state envelope in the 'mean stress, deviatoric stress' diagram. The attractive feature of this new yield envelope formulation relies on the fact that only the two most common different mechanical tests 'Uniaxial Compression' and 'Hydrostatic Compression', are needed to define entirely the yield envelope. Volumic strains and normalized permeabilities are finally mapped in the stresses diagram and correlated.

Closed-Loop Evaluation of an Integrated Failure Identification and Fault Tolerant Control System for a Transport Aircraft

NASA Technical Reports Server (NTRS)

Shin, Jong-Yeob; Belcastro, Christine; Khong, thuan

2006-01-01

Formal robustness analysis of aircraft control upset prevention and recovery systems could play an important role in their validation and ultimate certification. Such systems developed for failure detection, identification, and reconfiguration, as well as upset recovery, need to be evaluated over broad regions of the flight envelope or under extreme flight conditions, and should include various sources of uncertainty. To apply formal robustness analysis, formulation of linear fractional transformation (LFT) models of complex parameter-dependent systems is required, which represent system uncertainty due to parameter uncertainty and actuator faults. This paper describes a detailed LFT model formulation procedure from the nonlinear model of a transport aircraft by using a preliminary LFT modeling software tool developed at the NASA Langley Research Center, which utilizes a matrix-based computational approach. The closed-loop system is evaluated over the entire flight envelope based on the generated LFT model which can cover nonlinear dynamics. The robustness analysis results of the closed-loop fault tolerant control system of a transport aircraft are presented. A reliable flight envelope (safe flight regime) is also calculated from the robust performance analysis results, over which the closed-loop system can achieve the desired performance of command tracking and failure detection.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geier, S.; Schaffenroth, V.; Drechsel, H.

Hot subdwarf B stars (sdBs) are extreme horizontal branch stars believed to originate from close binary evolution. Indeed about half of the known sdB stars are found in close binaries with periods ranging from a few hours to a few days. The enormous mass loss required to remove the hydrogen envelope of the red-giant progenitor almost entirely can be explained by common envelope ejection. A rare subclass of these binaries are the eclipsing HW Vir binaries where the sdB is orbited by a dwarf M star. Here, we report the discovery of an HW Vir system in the course ofmore » the MUCHFUSS project. A most likely substellar object ({approx_equal}0.068 M{sub sun}) was found to orbit the hot subdwarf J08205+0008 with a period of 0.096 days. Since the eclipses are total, the system parameters are very well constrained. J08205+0008 has the lowest unambiguously measured companion mass yet found in a subdwarf B binary. This implies that the most likely substellar companion has not only survived the engulfment by the red-giant envelope, but also triggered its ejection and enabled the sdB star to form. The system provides evidence that brown dwarfs may indeed be able to significantly affect late stellar evolution.« less

Flight-Test Evaluation of Flutter-Prediction Methods

NASA Technical Reports Server (NTRS)

Lind, RIck; Brenner, Marty

2003-01-01

The flight-test community routinely spends considerable time and money to determine a range of flight conditions, called a flight envelope, within which an aircraft is safe to fly. The cost of determining a flight envelope could be greatly reduced if there were a method of safely and accurately predicting the speed associated with the onset of an instability called flutter. Several methods have been developed with the goal of predicting flutter speeds to improve the efficiency of flight testing. These methods include (1) data-based methods, in which one relies entirely on information obtained from the flight tests and (2) model-based approaches, in which one relies on a combination of flight data and theoretical models. The data-driven methods include one based on extrapolation of damping trends, one that involves an envelope function, one that involves the Zimmerman-Weissenburger flutter margin, and one that involves a discrete-time auto-regressive model. An example of a model-based approach is that of the flutterometer. These methods have all been shown to be theoretically valid and have been demonstrated on simple test cases; however, until now, they have not been thoroughly evaluated in flight tests. An experimental apparatus called the Aerostructures Test Wing (ATW) was developed to test these prediction methods.

3D multifunctional integumentary membranes for spatiotemporal cardiac measurements and stimulation across the entire epicardium

PubMed Central

Xu, Lizhi; Gutbrod, Sarah R.; Bonifas, Andrew P.; Su, Yewang; Sulkin, Matthew S.; Lu, Nanshu; Chung, Hyun-Joong; Jang, Kyung-In; Liu, Zhuangjian; Ying, Ming; Lu, Chi; Webb, R. Chad; Kim, Jong-Seon; Laughner, Jacob I.; Cheng, Huanyu; Liu, Yuhao; Ameen, Abid; Jeong, Jae-Woong; Kim, Gwang-Tae; Huang, Yonggang; Efimov, Igor R.; Rogers, John A.

2015-01-01

Means for high-density multiparametric physiological mapping and stimulation are critically important in both basic and clinical cardiology. Current conformal electronic systems are essentially 2D sheets, which cannot cover the full epicardial surface or maintain reliable contact for chronic use without sutures or adhesives. Here we create 3D elastic membranes shaped precisely to match the epicardium of the heart via the use of 3D printing, as a platform for deformable arrays of multifunctional sensors, electronic and optoelectronic components. Such integumentary devices completely envelop the heart, in a form-fitting manner, and possess inherent elasticity, providing a mechanically stable bioti-/abiotic interface during normal cardiac cycles. Component examples range from actuators for electrical, thermal and optical stimulation, to sensors for pH, temperature and mechanical strain. The semiconductor materials include silicon, gallium arsenide and gallium nitride, co-integrated with metals, metal oxides and polymers, to provide these and other operational capabilities. Ex vivo physiological experiments demonstrate various functions and methodological possibilities for cardiac research and therapy. PMID:24569383

Delivering better power: the role of simulation in reducing the environmental impact of aircraft engines.

PubMed

Menzies, Kevin

2014-08-13

The growth in simulation capability over the past 20 years has led to remarkable changes in the design process for gas turbines. The availability of relatively cheap computational power coupled to improvements in numerical methods and physical modelling in simulation codes have enabled the development of aircraft propulsion systems that are more powerful and yet more efficient than ever before. However, the design challenges are correspondingly greater, especially to reduce environmental impact. The simulation requirements to achieve a reduced environmental impact are described along with the implications of continued growth in available computational power. It is concluded that achieving the environmental goals will demand large-scale multi-disciplinary simulations requiring significantly increased computational power, to enable optimization of the airframe and propulsion system over the entire operational envelope. However even with massive parallelization, the limits imposed by communications latency will constrain the time required to achieve a solution, and therefore the position of such large-scale calculations in the industrial design process. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

CNO isotopes in red giant stars

NASA Technical Reports Server (NTRS)

Wannier, P. G.

1985-01-01

The production and distribution of the CNO nuclides is discussed in light of observed abundance ratios in red giants and in the interstellar medium. Isotope abundances have been measured in the atmospheres and in the recent ejecta of cool giants, including carbon stars, S-type stars and red supergiants as well as in oxygen-rich giants making their first ascent of the giant branch. Several of the observations suggest revision of currently accepted nuclear cross-sections and of the mixing processes operating in giant envelopes. By comparing red giant abundances with high-quality observations of the interstellar medium, conclusions are reached about the contribution of intermediate-mass stars to galactic nuclear evolution. The three oxygen isotopes, O-16, -17 and -18, are particularly valuable for such comparison because they reflect three different stages of stellar nucleosynthesis. One remarkable result comes from observations of O-17/O-18 in several classes of red giant stars. The observed range of values for red giants excludes the entire range of values seen in interstellar molecular clouds. Furthermore, both the observations of stars and interstellar clouds exclude the isotopic ratio found in the solar system.

Heavy Gas Conversion of the NASA Langley Transonic Dynamics Tunnel

NASA Technical Reports Server (NTRS)

Corliss, James M.; Cole, Stanley, R.

1998-01-01

The heavy gas test medium has recently been changed in the Transonic Dynamics Tunnel (TDT) at the NASA Langley Research Center. A NASA Construction of Facilities project has converted the TDT heavy gas from dichlorodifluoromethane (R12) to 1,1,1,2 tetrafluoroethane (R134a). The facility s heavy gas processing system was extensively modified to implement the conversion to R134a. Additional system modifications have improved operator interfaces, hardware reliability, and quality of the research data. The facility modifications included improvements to the heavy gas compressor and piping, the cryogenic heavy gas reclamation system, and the heavy gas control room. A series of wind tunnel characterization and calibration tests are underway. Results of the flow characterization tests show the TDT operating envelope in R134a to be very similar to the previous operating envelope in R12.

An evolutionary insight into the hatching strategies of pipefish and seahorse embryos.

PubMed

Kawaguchi, Mari; Nakano, Yuko; Kawahara-Miki, Ryouka; Inokuchi, Mayu; Yorifuji, Makiko; Okubo, Ryohei; Nagasawa, Tatsuki; Hiroi, Junya; Kono, Tomohiro; Kaneko, Toyoji

2016-03-01

Syngnathiform fishes carry their eggs in a brood structure found in males. The brood structure differs from species to species: seahorses carry eggs within enclosed brood pouch, messmate pipefish carry eggs in the semi-brood pouch, and alligator pipefish carry eggs in the egg compartment on abdomen. These egg protection strategies were established during syngnathiform evolution. In the present study, we compared the hatching mode of protected embryos of three species. Electron microscopic observations revealed that alligator pipefish and messmate pipefish egg envelopes were thicker than those of seahorses, suggesting that the seahorse produces a weaker envelope. Furthermore, molecular genetic analysis revealed that these two pipefishes possessed the egg envelope-digesting enzymes, high choriolytic enzyme (HCE), and low choriolytic enzyme (LCE), as do many euteleosts. In seahorses, however, only HCE gene expression was detected. When searching the entire seahorse genome by high-throughput DNA sequencing, we did not find a functional LCE gene and only a trace of the LCE gene exon was found, confirming that the seahorse LCE gene was pseudogenized during evolution. Finally, we estimated the size and number of hatching gland cells expressing hatching enzyme genes by whole-mount in situ hybridization. The seahorse cells were the smallest of the three species, while they had the greatest number. These results suggest that the isolation of eggs from the external environment by paternal bearing might bring the egg envelope thin, and then, the hatching enzyme genes became pseudogenized. J. Exp. Zool. (Mol. Dev. Evol.) 9999B:XX-XX, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Differential induction of anti-V3 crown antibodies with cradle- and ladle-binding modes in response to HIV-1 envelope vaccination.

PubMed

Balasubramanian, Preetha; Kumar, Rajnish; Williams, Constance; Itri, Vincenza; Wang, Shixia; Lu, Shan; Hessell, Ann J; Haigwood, Nancy L; Sinangil, Faruk; Higgins, Keith W; Liu, Lily; Li, Liuzhe; Nyambi, Phillipe; Gorny, Miroslaw K; Totrov, Maxim; Nadas, Arthur; Kong, Xiang-Peng; Zolla-Pazner, Susan; Hioe, Catarina E

2017-03-07

The V3 loop in the HIV envelope gp120 is one of the immunogenic sites targeted by Abs. The V3 crown in particular has conserved structural elements recognized by cross-reactive neutralizing Abs, indicating its potential contribution in protection against HIV. Crystallographic analyses of anti-V3 crown mAbs in complex with the V3 peptides have revealed that these mAbs recognize the conserved sites on the V3 crown via two distinct strategies: a cradle-binding mode (V3C) and a ladle-binding (V3L) mode. However, almost all of the anti-V3 crown mAbs studied in the past were isolated from chronically HIV-infected individuals. The extents to which the two types of anti-V3 crown Abs are generated by vaccination are unknown. This study analyzed the prevalence of V3C-type and V3L-type Ab responses in HIV-infected individuals and in HIV envelope-immunized humans and animals using peptide mimotopes that distinguish the two Ab types. The results show that both V3L-type and V3C-type Abs were generated by the vast majority of chronically HIV-infected humans, although the V3L-type were more prevalent. In contrast, only one of the two V3 Ab types was elicited in vaccinated humans or animal models, irrespective of HIV-1 envelope clades, envelope constructs (oligomeric or monomeric), and protocols (DNA plus protein or protein alone) used for vaccinations. The V3C-type Abs were produced by vaccinated humans, macaques, and rabbits, whereas the V3L-type Abs were made by mice. The V3C-type and V3L-type Abs generated by the vaccinations were able to mediate virus neutralization. These data indicate the restricted repertoires and the species-specific differences in the functional V3-specific Ab responses induced by the HIV envelope vaccines. The study implies the need for improving immunogen designs and vaccination strategies to broaden the diversity of Abs in order to target the different conserved epitopes in the V3 loop and, by extension, in the entire HIV envelope. Published by Elsevier Ltd.

Extending the Operational Envelope of a Turbofan Engine Simulation into the Sub-Idle Region

NASA Technical Reports Server (NTRS)

Chapman, Jeffryes W.; Hamley, Andrew J.; Guo, Ten-Huei; Litt, Jonathan S.

2016-01-01

In many non-linear gas turbine simulations, operation in the sub-idle region can lead to model instability. This paper lays out a method for extending the operational envelope of a map based gas turbine simulation to include the sub-idle region. This method develops a multi-simulation solution where the baseline component maps are extrapolated below the idle level and an alternate model is developed to serve as a safety net when the baseline model becomes unstable or unreliable. Sub-idle model development takes place in two distinct operational areas, windmilling/shutdown and purge/cranking/ startup. These models are based on derived steady state operating points with transient values extrapolated between initial (known) and final (assumed) states. Model transitioning logic is developed to predict baseline model sub-idle instability, and transition smoothly and stably to the backup sub-idle model. Results from the simulation show a realistic approximation of sub-idle behavior as compared to generic sub-idle engine performance that allows the engine to operate continuously and stably from shutdown to full power.

Extending the Operational Envelope of a Turbofan Engine Simulation into the Sub-Idle Region

NASA Technical Reports Server (NTRS)

Chapman, Jeffryes Walter; Hamley, Andrew J.; Guo, Ten-Huei; Litt, Jonathan S.

2016-01-01

In many non-linear gas turbine simulations, operation in the sub-idle region can lead to model instability. This paper lays out a method for extending the operational envelope of a map based gas turbine simulation to include the sub-idle region. This method develops a multi-simulation solution where the baseline component maps are extrapolated below the idle level and an alternate model is developed to serve as a safety net when the baseline model becomes unstable or unreliable. Sub-idle model development takes place in two distinct operational areas, windmilling/shutdown and purge/cranking/startup. These models are based on derived steady state operating points with transient values extrapolated between initial (known) and final (assumed) states. Model transitioning logic is developed to predict baseline model sub-idle instability, and transition smoothly and stably to the backup sub-idle model. Results from the simulation show a realistic approximation of sub-idle behavior as compared to generic sub-idle engine performance that allows the engine to operate continuously and stably from shutdown to full power.

Integration of frequency modulated constant envelope technique with ADO-OFDM to impede PAPR in VLC

NASA Astrophysics Data System (ADS)

Singh, Vinay Kumar; Dalal, U. D.

2018-07-01

A novel technique of combating the effects of high peak to average power ratio (PAPR) arising due to the non-linearity of the LED in a typical optical-OFDM (O-OFDM) for visible light communication (VLC) systems used in optical wireless channel (OWC) is proposed in this research work. The concept of constant envelope (CE) using frequency modulation (FM) for a composite O-OFDM system formed by uniting Asymmetrically Clipped Optical OFDM (ACO-OFDM) and Direct Current biased Optical OFDM (DCO-OFDM) termed as ADO-OFDM is mathematically presented with its numerical simulation results. The proposed system FM-CE-ADO-OFDM shows improvement in the PAPR with narrowing down to the least possible 0 dB theoretically. The analysis is extended to be compared with the phase modulation (PM) technique of CE-OFDM. The magnitude of phase discontinuity in the two systems is evaluated in the form of metrics yielding favorable results for the proposed system. This system is as spectrally efficient as the DCO-OFDM and as power efficient as the ACO-OFDM with the added advantage of major reduction in the effects due to PAPR arising as a result of the nonlinearity of the LED . The so formed FM-CE-ADO-OFDM is fed to the LED biased in the linear most region of its operation for simulation purpose. We also evaluate the depth of modulation required to obtain least bit error rate (BER). The frequency modulation at 30% depth has been observed to give suitable performance. The entire system is evaluated for an OWC length of 2m resembling the indoor illumination scenario. The receiver sensitivity shows an improvement of 1.2 dB at the FEC threshold for the proposed system.

SENSITIVITY OF THE HOUSE PRESSURE TEST FOR DUCT LEAKAGE TO VARIATIONS IN THE DISTRIBUTION OF AIR LEAKAGE IN THE HOUSE ENVELOPE

DOE Office of Scientific and Technical Information (OSTI.GOV)

ANDREWS,J.W.

1998-12-01

The house pressure test for air leakage in ducts calculates the signed difference between the supply and return leakage from the response of the air pressure in the house to operation of the system fan. The currently accepted version of this calculation was based on particular assumptions about how the house envelope leakage is distributed between the walls, ceiling, and floor. This report generalizes the equation to account for an arbitrary distribution of envelope leakage. It concludes that the currently accepted equation is usually accurate to within {+-}5%, but in a small proportion of cases the results may diverge bymore » 50% or more.« less

Flight testing a V/STOL aircraft to identify a full-envelope aerodynamic model

NASA Technical Reports Server (NTRS)

Mcnally, B. David; Bach, Ralph E., Jr.

1988-01-01

Flight-test techniques are being used to generate a data base for identification of a full-envelope aerodynamic model of a V/STOL fighter aircraft, the YAV-8B Harrier. The flight envelope to be modeled includes hover, transition to conventional flight and back to hover, STOL operation, and normal cruise. Standard V/STOL procedures such as vertical takeoff and landings, and short takeoff and landings are used to gather data in the powered-lift flight regime. Long (3 to 5 min) maneuvers which include a variety of input types are used to obtain large-amplitude control and response excitations. The aircraft is under continuous radar tracking; a laser tracker is used for V/STOL operations near the ground. Tracking data are used with state-estimation techniques to check data consistency and to derive unmeasured variables, for example, angular accelerations. A propulsion model of the YAV-8B's engine and reaction control system is used to isolate aerodynamic forces and moments for model identification. Representative V/STOL flight data are presented. The processing of a typical short takeoff and slow landing maneuver is illustrated.

Intermediate Temperature Fluids Life Tests - Experiments

NASA Technical Reports Server (NTRS)

Anderson, William G.; Bonner, Richard W.; Dussinger, Peter M.; Hartenstine, John R.; Sarraf, David B.; Locci, Ivan E.

2007-01-01

There are a number of different applications that could use heat pipes or loop heat pipes (LHPs) in the intermediate temperature range of 450 to 725 K (170 to 450 C), including space nuclear power system radiators, fuel cells, and high temperature electronics cooling. Historically, water has been used in heat pipes at temperatures up to about 425 K (150 C). Recent life tests, updated below, demonstrate that titanium/water and Monel/water heat pipes can be used at temperatures up to 550 K (277 C), due to water's favorable transport properties. At temperatures above roughly 570 K (300 C), water is no longer a suitable fluid, due to high vapor pressure and low surface tension as the critical point is approached. At higher temperatures, another working fluid/envelope combination is required, either an organic or halide working fluid. An electromotive force method was used to predict the compatibility of halide working fluids with envelope materials. This procedure was used to reject aluminum and aluminum alloys as envelope materials, due to their high decomposition potential. Titanium and three corrosion resistant superalloys were chosen as envelope materials. Life tests were conducted with these envelopes and six different working fluids: AlBr3, GaCl3, SnCl4, TiCl4, TiBr4, and eutectic diphenyl/diphenyl oxide (Therminol VP-1/Dowtherm A). All of the life tests except for the GaCl3 are ongoing; the GaCl3 was incompatible. As the temperature approaches 725 K (450 C), cesium is a potential heat pipe working fluid. Life tests results are also presented for cesium/Monel 400 and cesium/70-30 copper/nickel heat pipes operating near 750 K (477 C). These materials are not suitable for long term operation, due to copper transport from the condenser to the evaporator.

Adaptive Neuro-Fuzzy Modeling of UH-60A Pilot Vibration

NASA Technical Reports Server (NTRS)

Kottapalli, Sesi; Malki, Heidar A.; Langari, Reza

2003-01-01

Adaptive neuro-fuzzy relationships have been developed to model the UH-60A Black Hawk pilot floor vertical vibration. A 200 point database that approximates the entire UH-60A helicopter flight envelope is used for training and testing purposes. The NASA/Army Airloads Program flight test database was the source of the 200 point database. The present study is conducted in two parts. The first part involves level flight conditions and the second part involves the entire (200 point) database including maneuver conditions. The results show that a neuro-fuzzy model can successfully predict the pilot vibration. Also, it is found that the training phase of this neuro-fuzzy model takes only two or three iterations to converge for most cases. Thus, the proposed approach produces a potentially viable model for real-time implementation.

Operating envelope charts for the Langley 0.3-meter transonic cryogenic wind tunnel

NASA Technical Reports Server (NTRS)

Rallo, R. A.; Dress, D. A.; Siegle, H. J. A.

1986-01-01

To take full advantage of the unique Reynolds number capabilities of the 0.3-meter Transonic Cryogenic Tunnel (0.3-m TCT) at the NASA Langley Research Center, it was designed to accommodate test sections other than the original, octagonal, three-dimensional test section. A 20- by 60-cm two-dimensional test section was installed in 1976 and was extensively used, primarily for airfoil testing, through the fall of 1984. The tunnel was inactive during 1985 so that a new test section and improved high speed diffuser could be installed in the tunnel circuit. The new test section has solid adaptive top and bottom walls to reduce or eliminate wall interference for two-dimensional testing. The test section is 33- by 33-cm in cross section at the entrance and is 142 cm long. In the planning and running of past airfoil tests in the 0.3-m TCT, the use of operating envelope charts have proven very useful. These charts give the variation of total temperature and pressure with Mach number and Reynolds number. The operating total temperature range of the 0.3-m TCT is from about 78 K to 327 K with total pressures ranging from about 17.5 psia to 88 psia. This report presents the operating envelope charts for the 0.3-m TCT with the adaptive wall tes t section installed. They were all generated based on a 1-foot chord model. The Mach numbers vary from 0.1 to 0.95.

36 CFR 51.45 - Will a concessioner that has operated for less than the entire term of a concession contract be...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Will a concessioner that has operated for less than the entire term of a concession contract be considered a satisfactory operator? 51... for less than the entire term of a concession contract be considered a satisfactory operator? The...

Control Design for an Advanced Geared Turbofan Engine

NASA Technical Reports Server (NTRS)

Chapman, Jeffryes W.; Litt, Jonathan S.

2017-01-01

This paper describes the design process for the control system of an advanced geared turbofan engine. This process is applied to a simulation that is representative of a 30,000 pound-force thrust class concept engine with two main spools, ultra-high bypass ratio, and a variable area fan nozzle. Control system requirements constrain the non-linear engine model as it operates throughout its flight envelope of sea level to 40,000 feet and from 0 to 0.8 Mach. The purpose of this paper is to review the engine control design process for an advanced turbofan engine configuration. The control architecture selected for this project was developed from literature and reflects a configuration that utilizes a proportional integral controller with sets of limiters that enable the engine to operate safely throughout its flight envelope. Simulation results show the overall system meets performance requirements without exceeding operational limits.

Directional Slack-Based Measure for the Inverse Data Envelopment Analysis

PubMed Central

Abu Bakar, Mohd Rizam; Lee, Lai Soon; Jaafar, Azmi B.; Heydar, Maryam

2014-01-01

A novel technique has been introduced in this research which lends its basis to the Directional Slack-Based Measure for the inverse Data Envelopment Analysis. In practice, the current research endeavors to elucidate the inverse directional slack-based measure model within a new production possibility set. On one occasion, there is a modification imposed on the output (input) quantities of an efficient decision making unit. In detail, the efficient decision making unit in this method was omitted from the present production possibility set but substituted by the considered efficient decision making unit while its input and output quantities were subsequently modified. The efficiency score of the entire DMUs will be retained in this approach. Also, there would be an improvement in the efficiency score. The proposed approach was investigated in this study with reference to a resource allocation problem. It is possible to simultaneously consider any upsurges (declines) of certain outputs associated with the efficient decision making unit. The significance of the represented model is accentuated by presenting numerical examples. PMID:24883350

Flight Test Results on the Stability and Control of the F-15B Quiet Spike Aircraft

NASA Technical Reports Server (NTRS)

Moua, Cheng; McWherter, Shaun H.; Cox, Timothy H.; Gera, Joseph

2007-01-01

The Quiet Spike (QS) flight research program was an aerodynamic and structural proof-of-concept of a telescoping sonic-boom suppressing nose boom on an F-15 B aircraft. The program goal was to collect flight data for model validation up to 1.8 Mach. The primary test philosophy was maintaining safety of flight. In the area of stability and controls the primary concerns were to assess the potential destabilizing effect of the spike on the stability, controllability, and handling qualities of the aircraft and to ensure adequate stability margins across the entire QS flight envelop. This paper reports on the stability and control methods used for flight envelope clearance and flight test results of the F-15B Quiet Spike. Also discussed are the flight test approach, the criteria to proceed to the next flight condition, brief pilot commentary on typical piloting tasks, approach and landing, and refueling task, and air data sensitivity to the flight control system.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clausen, Drew; Wade, Richard A.; Kopparapu, Ravi Kumar

Binaries that contain a hot subdwarf (sdB) star and a main-sequence companion may have interacted in the past. This binary population has historically helped determine our understanding of binary stellar evolution. We have computed a grid of binary population synthesis models using different assumptions about the minimum core mass for helium ignition, the envelope binding energy, the common-envelope ejection efficiency, the amount of mass and angular momentum lost during stable mass transfer, and the criteria for stable mass transfer on the red giant branch and in the Hertzsprung gap. These parameters separately and together can significantly change the entire predictedmore » population of sdBs. Nonetheless, several different parameter sets can reproduce the observed subpopulation of sdB + white dwarf and sdB + M dwarf binaries, which has been used to constrain these parameters in previous studies. The period distribution of sdB + early F dwarf binaries offers a better test of different mass transfer scenarios for stars that fill their Roche lobes on the red giant branch.« less

Hydrodynamic models for novae with ejecta rich in oxygen, neon and magnesium

NASA Technical Reports Server (NTRS)

Starrfield, S.; Sparks, W. M.; Truran, J. W.

1985-01-01

The characteristics of a new class of novae are identified and explained. This class consists of those objects that have been observed to eject material rich in oxygen, neon, magnesium, and aluminum at high velocities. We propose that for this class of novae the outburst is occurring not on a carbon-oxygen white dwarf but on an oxygen-neon-magnesium white dwarf which has evolved from a star which had a main sequence mass of approx. 8 solar masses to approx. 12 solar masses. An outburst was simulated by evolving 1.25 solar mass white dwarfs accreting hydrogen rich material at various rates. The effective enrichment of the envelope by ONeMg material from the core is simulated by enhancing oxygen in the accreted layers. The resulting evolutionary sequences can eject the entire accreted envelope plus core material at high velocities. They can also become super-Eddington at maximum bolometric luminosity. The expected frequency of such events (approx. 1/4) is in good agreement with the observed numbers of these novae.

Analogies between respiration and a light-driven proton pump as sources of energy for active glutamate transport in Halobacterium halobium

NASA Technical Reports Server (NTRS)

Belliveau, J. W.; Lanyi, J. K.

1977-01-01

Halobacterium halobium is known to contain sheets of bacteriorhodopsin, a pigment which upon exposure to light undergoes cyclic protonation and deprotonation, resulting in net H(+) translocation. In this paper, experiments were conducted to test H. halobium cell envelope vesicles for respiration-induced glutamate uptake. It is shown that glutamate transport in H. halobium cell envelope vesicles can occur as a result of respiration, as well as light acting on bacteriorhodopsin. Glutamate transport can be energized by the oxidation of dimethyl phenylenediamine, and the properties of the transport system are entirely analogous to those observed with illumination as the source of energy. In the case of respiration-dependent glutamate transport, the transportation is also driven by a Na(+) gradient, thereby confirming the existence of a single glutamate transport system independent of the source of energy. The analogy observed is indirect evidence that the cytochrome oxidase of H. halobium functions as a H(+) pump.

Time reversal of arbitrary photonic temporal modes via nonlinear optical frequency conversion

NASA Astrophysics Data System (ADS)

Raymer, Michael G.; Reddy, Dileep V.; van Enk, Steven J.; McKinstrie, Colin J.

2018-05-01

Single-photon wave packets can carry quantum information between nodes of a quantum network. An important general operation in photon-based quantum information systems is ‘blind’ reversal of a photon’s temporal wave packet envelope, that is, the ability to reverse an envelope without knowing the temporal state of the photon. We present an all-optical means for doing so, using nonlinear-optical frequency conversion driven by a short pump pulse. The process used may be sum-frequency generation or four-wave Bragg scattering. This scheme allows for quantum operations such as a temporal-mode parity sorter. We also verify that the scheme works for arbitrary states (not only single-photon ones) of an unknown wave packet.

Circumstellar radio molecular lines

NASA Technical Reports Server (NTRS)

NGUYEN-QUANG-RIEU

1987-01-01

Radio molecular lines appear to be useful probes into the stellar environment. Silicon oxide masers provide information on the physical conditions in the immediate vicinity of the stellar photosphere. Valuable information on the physics operating in the envelope of IRC + 10216 was recently obtained by high sensitivity observations and detailed theoretical analyses. Infrared speckle interferometry in the molecular lines and in the continuum is helpful in the investigation of the inner region of the envelope. These techniques are discussed in terms of late-type star mass loss.

An Adaptive Nonlinear Aircraft Maneuvering Envelope Estimation Approach for Online Applications

NASA Technical Reports Server (NTRS)

Schuet, Stefan R.; Lombaerts, Thomas Jan; Acosta, Diana; Wheeler, Kevin; Kaneshige, John

2014-01-01

A nonlinear aircraft model is presented and used to develop an overall unified robust and adaptive approach to passive trim and maneuverability envelope estimation with uncertainty quantification. The concept of time scale separation makes this method suitable for the online characterization of altered safe maneuvering limitations after impairment. The results can be used to provide pilot feedback and/or be combined with flight planning, trajectory generation, and guidance algorithms to help maintain safe aircraft operations in both nominal and off-nominal scenarios.

Preserving the Helmholtz dispersion relation: One-way acoustic wave propagation using matrix square roots

NASA Astrophysics Data System (ADS)

Keefe, Laurence

2016-11-01

Parabolized acoustic propagation in transversely inhomogeneous media is described by the operator update equation U (x , y , z + Δz) =eik0 (- 1 +√{ 1 + Z }) U (x , y , z) for evolution of the envelope of a wavetrain solution to the original Helmholtz equation. Here the operator, Z =∇T2 + (n2 - 1) , involves the transverse Laplacian and the refractive index distribution. Standard expansion techniques (on the assumption Z << 1)) produce pdes that approximate, to greater or lesser extent, the full dispersion relation of the original Helmholtz equation, except that none of them describe evanescent/damped waves without special modifications to the expansion coefficients. Alternatively, a discretization of both the envelope and the operator converts the operator update equation into a matrix multiply, and existing theorems on matrix functions demonstrate that the complete (discrete) Helmholtz dispersion relation, including evanescent/damped waves, is preserved by this discretization. Propagation-constant/damping-rates contour comparisons for the operator equation and various approximations demonstrate this point, and how poorly the lowest-order, textbook, parabolized equation describes propagation in lined ducts.

Design and testing of a model CELSS chamber robot

NASA Astrophysics Data System (ADS)

Davis, Mark; Dezego, Shawn; Jones, Kinzy; Kewley, Christopher; Langlais, Mike; McCarthy, John; Penny, Damon; Bonner, Tom; Funderburke, C. Ashley; Hailey, Ruth

1994-08-01

A robot system for use in an enclosed environment was designed and tested. The conceptual design will be used to assist in research performed by the Controlled Ecological Life Support System (CELSS) project. Design specifications include maximum load capacity, operation at specified environmental conditions, low maintenance, and safety. The robot system must not be hazardous to the sealed environment, and be capable of stowing and deploying within a minimum area of the CELSS chamber facility. This design consists of a telescoping robot arm that slides vertically on a shaft positioned in the center of the CELSS chamber. The telescoping robot arm consists of a series of links which can be fully extended to a length equal to the radius of the working envelope of the CELSS chamber. The vertical motion of the robot arm is achieved through the use of a combination ball screw/ball spline actuator system. The robot arm rotates cylindrically about the vertical axis through use of a turntable bearing attached to a central mounting structure fitted to the actuator shaft. The shaft is installed in an overhead rail system allowing the entire structure to be stowed and deployed within the CELSS chamber. The overhead rail system is located above the chamber's upper lamps and extends to the center of the CELSS chamber. The mounting interface of the actuator shaft and rail system allows the entire actuator shaft to be detached and removed from the CELSS chamber. When the actuator shaft is deployed, it is held fixed at the bottom of the chamber by placing a square knob on the bottom of the shaft into a recessed square fitting in the bottom of the chamber floor. A support boot ensures the rigidity of the shaft. Three student teams combined into one group designed a model of the CELSS chamber robot that they could build. They investigated materials, availability, and strength in their design. After the model arm and stand were built, the class performed pre-tests on the entire system. A stability pre-test was used to determine whether the model robot arm would tip over on the stand when it was fully extended. Results showed the stand tipped when 50 Newtons were applied horizontally to the top of the vertical shaft while the arm was fully extended.

Design and testing of a model CELSS chamber robot

NASA Technical Reports Server (NTRS)

Davis, Mark; Dezego, Shawn; Jones, Kinzy; Kewley, Christopher; Langlais, Mike; Mccarthy, John; Penny, Damon; Bonner, Tom; Funderburke, C. Ashley; Hailey, Ruth

1994-01-01

A robot system for use in an enclosed environment was designed and tested. The conceptual design will be used to assist in research performed by the Controlled Ecological Life Support System (CELSS) project. Design specifications include maximum load capacity, operation at specified environmental conditions, low maintenance, and safety. The robot system must not be hazardous to the sealed environment, and be capable of stowing and deploying within a minimum area of the CELSS chamber facility. This design consists of a telescoping robot arm that slides vertically on a shaft positioned in the center of the CELSS chamber. The telescoping robot arm consists of a series of links which can be fully extended to a length equal to the radius of the working envelope of the CELSS chamber. The vertical motion of the robot arm is achieved through the use of a combination ball screw/ball spline actuator system. The robot arm rotates cylindrically about the vertical axis through use of a turntable bearing attached to a central mounting structure fitted to the actuator shaft. The shaft is installed in an overhead rail system allowing the entire structure to be stowed and deployed within the CELSS chamber. The overhead rail system is located above the chamber's upper lamps and extends to the center of the CELSS chamber. The mounting interface of the actuator shaft and rail system allows the entire actuator shaft to be detached and removed from the CELSS chamber. When the actuator shaft is deployed, it is held fixed at the bottom of the chamber by placing a square knob on the bottom of the shaft into a recessed square fitting in the bottom of the chamber floor. A support boot ensures the rigidity of the shaft. Three student teams combined into one group designed a model of the CELSS chamber robot that they could build. They investigated materials, availability, and strength in their design. After the model arm and stand were built, the class performed pre-tests on the entire system. A stability pre-test was used to determine whether the model robot arm would tip over on the stand when it was fully extended. Results showed the stand tipped when 50 Newtons were applied horizontally to the top of the vertical shaft while the arm was fully extended. This proved that it was stable. Another pre-test was the actuator slip test used to determine if there is an adequate coefficient of friction between the actuator drive wheels and drive cable to enable the actuator to fully extend and retract the arm. This pre-test revealed that the coefficient of friction was not large enough to prevent slippage. Sandpaper was glued to the drive wheel and this eliminated the slippage problem. The class preformed a fit test in the CELSS chamber to ensure that the completed robot arm is capable of reaching the entire working envelope. The robot was centered in the chamber and the arm was fully extended to the sides of the chamber. The arm was also able to retract to clear the drain pipes separating the upper and lower plant trays.

Toward practical terahertz time-domain spectroscopy

NASA Astrophysics Data System (ADS)

Brigada, David J.

Terahertz time-domain spectroscopy is a promising technology for the identification of explosive and pharmaceutical substances in adverse conditions. It interacts strongly with intermolecular vibrational and rotational modes. Terahertz also passes through many common dielectric covering materials, allowing for the identification of substances in envelopes, wrapped in opaque plastic, or otherwise hidden. However, there are several challenges preventing the adoption of terahertz spectroscopy outside the laboratory. This dissertation examines the problems preventing widespread adoption of terahertz technology and attempts to resolve them. In order to use terahertz spectroscopy to identify substances, a spectrum measured of the target sample must be compared to the spectra of various known standard samples. This dissertation examines various methods that can be employed throughout the entire process of acquiring and transforming terahertz waveforms to improve the accuracy of these comparisons. The concepts developed in this dissertation directly apply to terahertz spectroscopy, but also carry implications for other spectroscopy methods, from Raman to mass spectrometry. For example, these techniques could help to lower the rate of false positives at airport security checkpoints. This dissertation also examines the implementation of several of these methods as a way to realize a fully self-contained, handheld, battery-operated terahertz spectrometer. This device also employs techniques to allow minimally-trained operators use terahertz to detect different substances of interest. It functions as a proof-of-concept of the true benefits of the improvements that have been developed in this dissertation.

Millimeter Wave Radar for Atmospheric Turbulence Characterization and Wind Profiling for Improved Naval Operations

DTIC Science & Technology

2016-12-29

airflows surrounding ships can be used to determine operational envelopes, more efficiently space incoming aircraft, and can be used in conjunction with...aircraft, and can be used in conjunction with simulations to inform and influence ship design. Another application is for high-energy laser propagation

An Analytical Investigation of the Heat Losses from a U.S. Navy K-Type Airship

NASA Technical Reports Server (NTRS)

Hillendahl, Wesley H.; George, Ralph E.

1946-01-01

The heat losses from the envelope surface of a U.S. Navy K-type airship are evaluated to determine if the use of heat is a feasible means of preventing ice and snow accumulations on lighter-than-air craft during flight and when moored uncovered. Consideration is given to heat losses in clear air (no liquid water present in the atmosphere) and in probable conditions of icing and snow. The results of the analysis indicate that the amount of heat required in flight to raise the surface temperature of the entire envelope to the extent considered adequate for ice protection, based on experience with tests of heavier-than-air craft, is very large. Existing types of heating equipment which could be used to supply this quantity of heat would probably be too bulky and heavy to provide a practical flight installation. The heat requirements to provide protection for the nose and stern regions in assumed mild to moderate icing conditions appear to be within the range of the capacity of current types of heating equipment suitable for flight use. The amount of heat necessary to prevent snow accumulations on the upper surface of the airship envelope when moored uncovered under all conditions appear to be excessive for the heating equipment presently available for flight use, but could possibly be achieved with auxiliary ground heating equipment.

Circumplanetary disc or circumplanetary envelope?

NASA Astrophysics Data System (ADS)

Szulágyi, J.; Masset, F.; Lega, E.; Crida, A.; Morbidelli, A.; Guillot, T.

2016-08-01

We present three-dimensional simulations with nested meshes of the dynamics of the gas around a Jupiter mass planet with the JUPITER and FARGOCA codes. We implemented a radiative transfer module into the JUPITER code to account for realistic heating and cooling of the gas. We focus on the circumplanetary gas flow, determining its characteristics at very high resolution (80 per cent of Jupiter's diameter). In our nominal simulation where the temperature evolves freely by the radiative module and reaches 13000 K at the planet, a circumplanetary envelope was formed filling the entire Roche lobe. Because of our equation of state is simplified and probably overestimates the temperature, we also performed simulations with limited maximal temperatures in the planet region (1000, 1500, and 2000 K). In these fixed temperature cases circumplanetary discs (CPDs) were formed. This suggests that the capability to form a CPD is not simply linked to the mass of the planet and its ability to open a gap. Instead, the gas temperature at the planet's location, which depends on its accretion history, plays also fundamental role. The CPDs in the simulations are hot and cooling very slowly, they have very steep temperature and density profiles, and are strongly sub-Keplerian. Moreover, the CPDs are fed by a strong vertical influx, which shocks on the CPD surfaces creating a hot and luminous shock-front. In contrast, the pressure supported circumplanetary envelope is characterized by internal convection and almost stalled rotation.

3D Analysis of HCMV Induced-Nuclear Membrane Structures by FIB/SEM Tomography: Insight into an Unprecedented Membrane Morphology

PubMed Central

Villinger, Clarissa; Neusser, Gregor; Kranz, Christine; Walther, Paul; Mertens, Thomas

2015-01-01

We show that focused ion beam/scanning electron microscopy (FIB/SEM) tomography is an excellent method to analyze the three-dimensional structure of a fibroblast nucleus infected with human cytomegalovirus (HCMV). We found that the previously described infoldings of the inner nuclear membrane, which are unique among its kind, form an extremely complex network of membrane structures not predictable by previous two-dimensional studies. In all cases they contained further invaginations (2nd and 3rd order infoldings). Quantification revealed 5498 HCMV capsids within two nuclear segments, allowing an estimate of 15,000 to 30,000 capsids in the entire nucleus five days post infection. Only 0.8% proved to be enveloped capsids which were exclusively detected in 1st order infoldings (perinuclear space). Distribution of the capsids between 1st, 2nd and 3rd order infoldings is in complete agreement with the envelopment/de-envelopment model for egress of HCMV capsids from the nucleus and we confirm that capsid budding does occur at the large infoldings. Based on our results we propose the pushing membrane model: HCMV infection induces local disruption of the nuclear lamina and synthesis of new membrane material which is pushed into the nucleoplasm, forming complex membrane infoldings in a highly abundant manner, which then may be also used by nucleocapsids for budding. PMID:26556360

Expanding the Envelope of UAS Certification: What it Takes to Type Certify a UAS for Precision Agricultural Spraying

NASA Technical Reports Server (NTRS)

Maddalon, J. M.; Hayhurst, K. J.; Neogi, N. A.; Verstynen, H. A.; Clothier, R. A.

2016-01-01

One of the key challenges to the development of a commercial Unmanned Air-craft System (UAS) market is the lack of explicit consideration of UAS in the current regulatory framework. Despite recent progress, additional steps are needed to enable broad UAS types and operational models. This paper discusses recent research that examines how a risk-based approach for safety might change the process and substance of airworthiness requirements for UAS. The project proposed risk-centric airworthiness requirements for a midsize un-manned rotorcraft used for agricultural spraying and also identified factors that may contribute to distinguishing safety risk among different UAS types and operational concepts. Lessons learned regarding how a risk-based approach can expand the envelope of UAS certification are discussed.

User manual for NASA Lewis 10 by 10 foot supersonic wind tunnel. Revised

NASA Technical Reports Server (NTRS)

Soeder, Ronald H.

1995-01-01

This manual describes the 10- by 10-Foot Supersonic Wind Tunnel at the NASA Lewis Research Center and provides information for users who wish to conduct experiments in this facility. Tunnel performance operating envelopes of altitude, dynamic pressure, Reynolds number, total pressure, and total temperature as a function of test section Mach number are presented. Operating envelopes are shown for both the aerodynamic (closed) cycle and the propulsion (open) cycle. The tunnel test section Mach number range is 2.0 to 3.5. General support systems, such as air systems, hydraulic system, hydrogen system, fuel system, and Schlieren system, are described. Instrumentation and data processing and acquisition systems are also described. Pretest meeting formats and schedules are outlined. Tunnel user responsibility and personnel safety are also discussed.

A model for the sustainable selection of building envelope assemblies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huedo, Patricia, E-mail: huedo@uji.es; Mulet, Elena, E-mail: emulet@uji.es; López-Mesa, Belinda, E-mail: belinda@unizar.es

2016-02-15

The aim of this article is to define an evaluation model for the environmental impacts of building envelopes to support planners in the early phases of materials selection. The model is intended to estimate environmental impacts for different combinations of building envelope assemblies based on scientifically recognised sustainability indicators. These indicators will increase the amount of information that existing catalogues show to support planners in the selection of building assemblies. To define the model, first the environmental indicators were selected based on the specific aims of the intended sustainability assessment. Then, a simplified LCA methodology was developed to estimate themore » impacts applicable to three types of dwellings considering different envelope assemblies, building orientations and climate zones. This methodology takes into account the manufacturing, installation, maintenance and use phases of the building. Finally, the model was validated and a matrix in Excel was created as implementation of the model. - Highlights: • Method to assess the envelope impacts based on a simplified LCA • To be used at an earlier phase than the existing methods in a simple way. • It assigns a score by means of known sustainability indicators. • It estimates data about the embodied and operating environmental impacts. • It compares the investment costs with the costs of the consumed energy.« less

Piloted Simulation Assessment of a High-Speed Civil Transport Configuration. [conducted with the Langley six-degree-of-freedom Visual Motion Simulator

NASA Technical Reports Server (NTRS)

Jackson, E. Bruce; Raney, David L.; Glaab, Louis J.; Derry, Stephen D.

2002-01-01

An assessment of a proposed configuration of a high-speed civil transport was conducted by using NASA and industry research pilots. The assessment was conducted to evaluate operational aspects of the configuration from a pilot's perspective, with the primary goal being to identify potential deficiencies in the configuration. The configuration was evaluated within and at the limits of the design operating envelope to determine the suitability of the configuration to maneuver in a typical mission as well as in emergency or envelope-limit conditions. The Cooper-Harper rating scale was used to evaluate the flying qualities of the configuration. A summary flying qualities metric was also calculated. The assessment was performed in the Langley six-degree-of-freedom Visual Motion Simulator. The effect of a restricted cockpit field-of-view due to obstruction by the vehicle nose was not included in this study. Tasks include landings, takeoffs, climbs, descents, overspeeds, coordinated turns, and recoveries from envelope limit excursions. Emergencies included engine failures, loss of stability augmentation, engine inlet unstarts, and emergency descents. Minimum control speeds and takeoff decision, rotation, and safety speeds were also determined.

Operating and Maintaining Energy Smart Schools Action Plan Template - All Action Plans

DOE Office of Scientific and Technical Information (OSTI.GOV)

none,

2009-07-01

EnergySmart Schools action plan templates for benchmarking, lighting, HVAC, water heating, building envelope, transformer, plug loads, kitchen equipment, swimming pool, building automation system, other.

Assessing Canadian Bank Branch Operating Efficiency Using Data Envelopment Analysis

NASA Astrophysics Data System (ADS)

Yang, Zijiang

2009-10-01

In today's economy and society, performance analyses in the services industries attract more and more attention. This paper presents an evaluation of 240 branches of one big Canadian bank in Greater Toronto Area using Data Envelopment Analysis (DEA). Special emphasis was placed on how to present the DEA results to management so as to provide more guidance to them on what to manage and how to accomplish the changes. Finally the potential management uses of the DEA results were presented. All the findings are discussed in the context of the Canadian banking market.

Measuring the performance of Internet companies using a two-stage data envelopment analysis model

NASA Astrophysics Data System (ADS)

Cao, Xiongfei; Yang, Feng

2011-05-01

In exploring the business operation of Internet companies, few researchers have used data envelopment analysis (DEA) to evaluate their performance. Since the Internet companies have a two-stage production process: marketability and profitability, this study employs a relational two-stage DEA model to assess the efficiency of the 40 dot com firms. The results show that our model performs better in measuring efficiency, and is able to discriminate the causes of inefficiency, thus helping business management to be more effective through providing more guidance to business performance improvement.

Treatment envelope evaluation in transcranial magnetic resonance-guided focused ultrasound utilizing 3D MR thermometry

PubMed Central

2014-01-01

Background Current clinical targets for transcranial magnetic resonance-guided focused ultrasound (tcMRgFUS) are all located close to the geometric center of the skull convexity, which minimizes challenges related to focusing the ultrasound through the skull bone. Non-central targets will have to be reached to treat a wider variety of neurological disorders and solid tumors. Treatment envelope studies utilizing two-dimensional (2D) magnetic resonance (MR) thermometry have previously been performed to determine the regions in which therapeutic levels of FUS can currently be delivered. Since 2D MR thermometry was used, very limited information about unintended heating in near-field tissue/bone interfaces could be deduced. Methods In this paper, we present a proof-of-concept treatment envelope study with three-dimensional (3D) MR thermometry monitoring of FUS heatings performed in a phantom and a lamb model. While the moderate-sized transducer used was not designed for transcranial geometries, the 3D temperature maps enable monitoring of the entire sonication field of view, including both the focal spot and near-field tissue/bone interfaces, for full characterization of all heating that may occur. 3D MR thermometry is achieved by a combination of k-space subsampling and a previously described temporally constrained reconstruction method. Results We present two different types of treatment envelopes. The first is based only on the focal spot heating—the type that can be derived from 2D MR thermometry. The second type is based on the relative near-field heating and is calculated as the ratio between the focal spot heating and the near-field heating. This utilizes the full 3D MR thermometry data achieved in this study. Conclusions It is shown that 3D MR thermometry can be used to improve the safety assessment in treatment envelope evaluations. Using a non-optimal transducer, it is shown that some regions where therapeutic levels of FUS can be delivered, as suggested by the first type of envelope, are not necessarily safely treated due to the amount of unintended near-field heating occurring. The results presented in this study highlight the need for 3D MR thermometry in tcMRgFUS. PMID:25343028

Mass Vertical Envelopment (Airborne) Operations: A Critical Capability in the Army After Next?

DTIC Science & Technology

2002-06-01

purpose of this thesis is to review the viability of mass airborne operations in the context of today’s modern war environment, specifically in a Major...context of today’s modern war environment, specifically in a Major Regional Contingency (MRC) scenario as outlined in the most current Quadrennial...8 1. World War II........................................................................................8 a. Invasion of Sicily (Operation Husky

Nanoparticles Suitable for BCAA Isolation Can Serve for Use in Magnetic Lipoplex-Based Delivery System for L, I, V, or R-rich Antimicrobial Peptides.

PubMed

Vesely, Radek; Jelinkova, Pavlina; Hegerova, Dagmar; Cernei, Natalia; Kopel, Pavel; Moulick, Amitava; Richtera, Lukas; Heger, Zbynek; Adam, Vojtech; Zitka, Ondrej

2016-03-31

This paper investigates the synthesis of paramagnetic nanoparticles, which are able to bind branched chain amino acids (BCAAs)-leucine, valine, and isoleucine and, thus, serve as a tool for their isolation. Further, by this, we present an approach for encapsulation of nanoparticles into a liposome cavity resulting in a delivery system. Analyses of valine and leucine in entire complex show that 31.3% and 32.6% recoveries are reached for those amino acids. Evaluation of results shows that the success rate of delivery in Escherichia coli ( E. coli ) is higher in the case of BCAAs on nanoparticles entrapped in liposomes (28.7% and 34.7% for valine and leucine, respectively) when compared to nanoparticles with no liposomal envelope (18.3% and 13.7% for valine and leucine, respectively). The nanoparticles with no liposomal envelope exhibit the negative zeta potential (-9.1 ± 0.3 mV); however, their encapsulation results in a shift into positive values (range of 28.9 ± 0.4 to 33.1 ± 0.5 mV). Thus, electrostatic interactions with negatively-charged cell membranes (approx. -50 mV in the case of E. coli ) leads to a better uptake of cargo. Our delivery system was finally tested with the leucine-rich antimicrobial peptide (FALALKALKKALKKLKKALKKAL) and it is shown that hemocompatibility (7.5%) and antimicrobial activity of the entire complex against E. coli , Staphylococcus aureus ( S. aureus ), and methicilin-resistant S. aureus (MRSA) is comparable or better than conventional penicillin antibiotics.

The AVIRIS Low Altitude Option-An Approach to Increase Geometric Resolution and Improve Operational Flexibility Simultaneously

NASA Technical Reports Server (NTRS)

Sarture, Charles M.; Chovit, Christopher J.; Chrien, Thomas G.; Eastwood, Michael L.; Green, Robert O.; Kurzwell, Charles G.

1998-01-01

From 1987 through 1997 the Airborne Visible-InfraRed Imaging Spectrometer has matured into a remote sensing instrument capable of producing prodigious amounts of high quality data. Using the NASA/Ames ER-2 high altitude aircraft platform, flight operations have become very reliable as well. Being exclusively dependent on the ER-2, however, has limitations: the ER-2 has a narrow cruise envelope which fixes the AVIRIS ground pixel at 20 meters; it requires a significant support infrastructure; and it has a very limited number of bases it can operate from. In the coming years, the ER-2 will also become less available for AVIRIS flights as NASA Earth Observing System satellite underflights increase. Adapting AVIRIS to lower altitude, less specialized aircraft will create a much broader envelope for data acquisition, i.e., higher ground geometric resolution while maintaining nearly the ideal spatial sampling. This approach will also greatly enhance flexibility while decreasing the overall cost of flight operations and field support. Successful adaptation is expected to culminate with a one-month period of demonstration flights.

Delving into sensible measures to enhance the environmental performance of biohydrogen: A quantitative approach based on process simulation, life cycle assessment and data envelopment analysis.

PubMed

Martín-Gamboa, Mario; Iribarren, Diego; Susmozas, Ana; Dufour, Javier

2016-08-01

A novel approach is developed to evaluate quantitatively the influence of operational inefficiency in biomass production on the life-cycle performance of hydrogen from biomass gasification. Vine-growers and process simulation are used as key sources of inventory data. The life cycle assessment of biohydrogen according to current agricultural practices for biomass production is performed, as well as that of target biohydrogen according to agricultural practices optimised through data envelopment analysis. Only 20% of the vineyards assessed operate efficiently, and the benchmarked reduction percentages of operational inputs range from 45% to 73% in the average vineyard. The fulfilment of operational benchmarks avoiding irregular agricultural practices is concluded to improve significantly the environmental profile of biohydrogen (e.g., impact reductions above 40% for eco-toxicity and global warming). Finally, it is shown that this type of bioenergy system can be an excellent replacement for conventional hydrogen in terms of global warming and non-renewable energy demand. Copyright © 2016 Elsevier Ltd. All rights reserved.

Recertification of the air and methane storage vessels at the Langley 8-foot high-temperature structures tunnel

NASA Technical Reports Server (NTRS)

Hudson, C. M.; Girouard, R. L.; Young, C. P., Jr.; Petley, D. H.; Hudson, J. L., Jr.; Hudgins, J. L.

1977-01-01

This center operates a number of sophisticated wind tunnels in order to fulfill the needs of its researchers. Compressed air, which is kept in steel storage vessels, is used to power many of these tunnels. Some of these vessels have been in use for many years, and Langley is currently recertifying these vessels to insure their continued structural integrity. One of the first facilities to be recertified under this program was the Langley 8-foot high-temperature structures tunnel. This recertification involved (1) modification, hydrotesting, and inspection of the vessels; (2) repair of all relevant defects; (3) comparison of the original design of the vessel with the current design criteria of Section 8, Division 2, of the 1974 ASME Boiler and Pressure Vessel Code; (4) fracture-mechanics, thermal, and wind-induced vibration analyses of the vessels; and (5) development of operating envelopes and a future inspection plan for the vessels. Following these modifications, analyses, and tests, the vessels were recertified for operation at full design pressure (41.4 MPa (6000 psi)) within the operating envelope developed.

14 CFR 23.907 - Propeller vibration and fatigue.

Code of Federal Regulations, 2010 CFR

2010-01-01

... stresses or loads, including any stress peaks and resonant conditions, throughout the operational envelope of the airplane by either: (1) Measurement of stresses or loads through direct testing or analysis...

14 CFR 23.907 - Propeller vibration and fatigue.

Code of Federal Regulations, 2012 CFR

2012-01-01

... stresses or loads, including any stress peaks and resonant conditions, throughout the operational envelope of the airplane by either: (1) Measurement of stresses or loads through direct testing or analysis...

14 CFR 23.907 - Propeller vibration and fatigue.

Code of Federal Regulations, 2011 CFR

2011-01-01

... stresses or loads, including any stress peaks and resonant conditions, throughout the operational envelope of the airplane by either: (1) Measurement of stresses or loads through direct testing or analysis...

Authorization basis supporting documentation for plutonium finishing plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

King, J.P., Fluor Daniel Hanford

1997-03-05

The identification and definition of the authorization basis for the Plutonium Finishing Plant (PFP) facility and operations are essential for compliance to DOE Order 5480.21, Unreviewed Safety Questions. The authorization basis, as defined in the Order, consists of those aspects of the facility design basis, i.e., the structures, systems and components (SSCS) and the operational requirements that are considered to be important to the safety of operations and are relied upon by DOE to authorize operation of the facility. These facility design features and their function in various accident scenarios are described in WHC-SD-CP-SAR-021, Plutonium Finishing Plant Final Safety Analysismore » Report (FSAR), Chapter 9, `Accident Analysis.` Figure 1 depicts the relationship of the Authorization Basis to its components and other information contained in safety documentation supporting the Authorization Basis. The PFP SSCs that are important to safety, collectively referred to as the `Safety Envelope` are discussed in various chapters of the FSAR and in WHC-SD-CP-OSR-010, Plutonium Finishing Plant Operational Safety Requirements. Other documents such as Criticality Safety Evaluation Reports (CSERS) address and support some portions of the Authorization Basis and Safety Envelope.« less

The Centrifuge Facility Life Sciences Glovebox configuration study

NASA Technical Reports Server (NTRS)

Sun, Sidney C.; Goulart, Carla V.

1992-01-01

Crew operations associated with nonhuman life sciences research on Space Station Freedom will be conducted in the Life Sciences Glovebox, whose enclosed work volume must accommodate numerous life science procedures. Two candidate Glovebox work volume concepts have been developed: one in which two operators work side-by-side, and another that conforms to the reach envelope of a single operator. Six test volunteers tested the concepts according to preestablished operational criteria. The wrap-around, single-operator concept has been judged the superior system.

Compact Modules for Wireless Communication Systems in the E-Band (71-76 GHz)

NASA Astrophysics Data System (ADS)

Montero-de-Paz, Javier; Oprea, Ion; Rymanov, Vitaly; Babiel, Sebastian; García-Muñoz, Luis Enrique; Lisauskas, Alvydas; Hoefle, Matthias; Jimenez, Álvaro; Cojocari, Oleg; Segovia-Vargas, Daniel; Palandöken, Merih; Tekin, Tolga; Stöhr, Andreas; Carpintero, Guillermo

2013-04-01

The millimeter-wave spectrum above 70 GHz provides a cost-effective solution to increase the wireless communications data rates by increasing the carrier wave frequencies. We report on the development of two key components of a wireless transmission system, a high-speed photodiode (HS-PD) and a Schottky Barrier Diode (SBD). Both components operate uncooled, a key issue in the development of compact modules. On the transmitter side, an improved design of the HS-PD allows it to deliver an output RF power exceeding 0 dBm (1 mW). On the receiver side, we present the design process and achieved results on the development of a compact direct envelope detection receiver based on a quasi-optical SDB module. Different resonant (meander dipole) and broadband (Log-Spiral and Log-Periodic) planar antenna solutions are designed, matching the antenna and Schottky diode impedances at high frequency. Impedance matching at baseband is also provided by means of an impedance transition to a 50 Ohm output. From this comparison, we demonstrate the excellent performance of the broadband antennas over the entire E-band by setting up a short-range wireless link transmitting a 1 Gbps data signal.

14 CFR 60.7 - Sponsor qualification requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... as described in paragraphs (b)(5) or (b)(6) of this section. (3) The person has a quality management... FSTD's performance and handling qualities, within the normal operating envelope, represent the aircraft...

Toward 2D Seismic Wavefield Monitoring: Seismic Gradiometry for Long-Period Seismogram and Short-Period Seismogram Envelope applied to the Hi-net Array

NASA Astrophysics Data System (ADS)

Maeda, T.; Nishida, K.; Takagi, R.; Obara, K.

2015-12-01

The high-sensitive seismograph network Japan (Hi-net) operated by National Research Institute for Earth Science and Disaster Prevention (NIED) has about 800 stations with average separation of 20 km. We can observe long-period seismic wave propagation as a 2D wavefield with station separations shorter than wavelength. In contrast, short-period waves are quite incoherent at stations, however, their envelope shapes resemble at neighbor stations. Therefore, we may be able to extract seismic wave energy propagation by seismogram envelope analysis. We attempted to characterize seismic waveform at long-period and its envelope at short-period as 2D wavefield by applying seismic gradiometry. We applied the seismic gradiometry to a synthetic long-period (20-50s) dataset prepared by numerical simulation in realistic 3D medium at the Hi-net station layout. Wave amplitude and its spatial derivatives are estimated by using data at nearby stations. The slowness vector, the radiation pattern and the geometrical spreading are extracted from estimated velocity, displacement and its spatial derivatives. For short-periods at shorter than 1 s, seismogram envelope shows temporal and spatial broadening through scattering by medium heterogeneity. It is expected that envelope shape may be coherent among nearby stations. Based on this idea, we applied the same method to the time-integration of seismogram envelope to estimate its spatial derivatives. Together with seismogram envelope, we succeeded in estimating the slowness vector from the seismogram envelope as well as long-period waveforms by synthetic test, without using phase information. Our preliminarily results show that the seismic gradiometry suits the Hi-net to extract wave propagation characteristics both at long and short periods. This method is appealing that it can estimate waves at homogeneous grid to monitor seismic wave as a wavefield. It is promising to obtain phase velocity variation from direct waves, and to grasp wave packets originating from scattering from coda, by applying the seismic gradiometry to the Hi-net.

KEPLER PLANETS: A TALE OF EVAPORATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Owen, James E.; Wu, Yanqin, E-mail: jowen@cita.utoronto.ca, E-mail: wu@astro.utoronto.ca

2013-10-01

Inspired by the Kepler mission's planet discoveries, we consider the thermal contraction of planets close to their parent star, under the influence of evaporation. The mass-loss rates are based on hydrodynamic models of evaporation that include both X-ray and EUV irradiation. We find that only low mass planets with hydrogen envelopes are significantly affected by evaporation, with evaporation being able to remove massive hydrogen envelopes inward of ∼0.1 AU for Neptune-mass objects, while evaporation is negligible for Jupiter-mass objects. Moreover, most of the evaporation occurs in the first 100 Myr of stars' lives when they are more chromospherically active. Wemore » construct a theoretical population of planets with varying core masses, envelope masses, orbital separations, and stellar spectral types, and compare this population with the sizes and densities measured for low-mass planets, both in the Kepler mission and from radial velocity surveys. This exercise leads us to conclude that evaporation is the driving force of evolution for close-in Kepler planets. In fact, some 50% of the Kepler planet candidates may have been significantly eroded. Evaporation explains two striking correlations observed in these objects: a lack of large radius/low density planets close to the stars and a possible bimodal distribution in planet sizes with a deficit of planets around 2 R{sub ⊕}. Planets that have experienced high X-ray exposures are generally smaller than this size, and those with lower X-ray exposures are typically larger. A bimodal planet size distribution is naturally predicted by the evaporation model, where, depending on their X-ray exposure, close-in planets can either hold on to hydrogen envelopes ∼0.5%-1% in mass or be stripped entirely. To quantitatively reproduce the observed features, we argue that not only do low-mass Kepler planets need to be made of rocky cores surrounded with hydrogen envelopes, but few of them should have initial masses above 20 M{sub ⊕} and the majority of them should have core masses of a few Earth masses.« less

Laboratory Evaluation of Energy Recovery Ventilators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kosar, D.

Over the years, building scientists have characterized the relationship between building airtightness, exhaust-only appliances airflows, and building depressurization. Now, as the use of deep retrofit measures and new construction practices is growing to realize lower infiltration levels in increasingly tighter envelopes, performance issues can arise with the operation of exhaust-only appliances in a depressurized home. As the depressurization levels climb in tighter homes, many of these exhaust-only appliances see their rated airflows reduced and other related performance issues arise as a result. If sufficiently depressurized, atmospherically vented combustion appliances that may be present in the home can backdraft as well.more » Furthermore, when exhaust-only appliances operate and the tight home becomes depressurized, water vapor intrusion from outdoors can raise additional issues of mold in the building envelope in more humid climates.« less

Robust network data envelopment analysis approach to evaluate the efficiency of regional electricity power networks under uncertainty.

PubMed

Fathollah Bayati, Mohsen; Sadjadi, Seyed Jafar

2017-01-01

In this paper, new Network Data Envelopment Analysis (NDEA) models are developed to evaluate the efficiency of regional electricity power networks. The primary objective of this paper is to consider perturbation in data and develop new NDEA models based on the adaptation of robust optimization methodology. Furthermore, in this paper, the efficiency of the entire networks of electricity power, involving generation, transmission and distribution stages is measured. While DEA has been widely used to evaluate the efficiency of the components of electricity power networks during the past two decades, there is no study to evaluate the efficiency of the electricity power networks as a whole. The proposed models are applied to evaluate the efficiency of 16 regional electricity power networks in Iran and the effect of data uncertainty is also investigated. The results are compared with the traditional network DEA and parametric SFA methods. Validity and verification of the proposed models are also investigated. The preliminary results indicate that the proposed models were more reliable than the traditional Network DEA model.

Robust network data envelopment analysis approach to evaluate the efficiency of regional electricity power networks under uncertainty

PubMed Central

Sadjadi, Seyed Jafar

2017-01-01

In this paper, new Network Data Envelopment Analysis (NDEA) models are developed to evaluate the efficiency of regional electricity power networks. The primary objective of this paper is to consider perturbation in data and develop new NDEA models based on the adaptation of robust optimization methodology. Furthermore, in this paper, the efficiency of the entire networks of electricity power, involving generation, transmission and distribution stages is measured. While DEA has been widely used to evaluate the efficiency of the components of electricity power networks during the past two decades, there is no study to evaluate the efficiency of the electricity power networks as a whole. The proposed models are applied to evaluate the efficiency of 16 regional electricity power networks in Iran and the effect of data uncertainty is also investigated. The results are compared with the traditional network DEA and parametric SFA methods. Validity and verification of the proposed models are also investigated. The preliminary results indicate that the proposed models were more reliable than the traditional Network DEA model. PMID:28953900

High Resolution Aerospace Applications using the NASA Columbia Supercomputer

NASA Technical Reports Server (NTRS)

Mavriplis, Dimitri J.; Aftosmis, Michael J.; Berger, Marsha

2005-01-01

This paper focuses on the parallel performance of two high-performance aerodynamic simulation packages on the newly installed NASA Columbia supercomputer. These packages include both a high-fidelity, unstructured, Reynolds-averaged Navier-Stokes solver, and a fully-automated inviscid flow package for cut-cell Cartesian grids. The complementary combination of these two simulation codes enables high-fidelity characterization of aerospace vehicle design performance over the entire flight envelope through extensive parametric analysis and detailed simulation of critical regions of the flight envelope. Both packages. are industrial-level codes designed for complex geometry and incorpor.ats. CuStomized multigrid solution algorithms. The performance of these codes on Columbia is examined using both MPI and OpenMP and using both the NUMAlink and InfiniBand interconnect fabrics. Numerical results demonstrate good scalability on up to 2016 CPUs using the NUMAIink4 interconnect, with measured computational rates in the vicinity of 3 TFLOP/s, while InfiniBand showed some performance degradation at high CPU counts, particularly with multigrid. Nonetheless, the results are encouraging enough to indicate that larger test cases using combined MPI/OpenMP communication should scale well on even more processors.

Adiabatic Mass Loss Model in Binary Stars

NASA Astrophysics Data System (ADS)

Ge, H. W.

2012-07-01

Rapid mass transfer process in the interacting binary systems is very complicated. It relates to two basic problems in the binary star evolution, i.e., the dynamically unstable Roche-lobe overflow and the common envelope evolution. Both of the problems are very important and difficult to be modeled. In this PhD thesis, we focus on the rapid mass loss process of the donor in interacting binary systems. The application to the criterion of dynamically unstable mass transfer and the common envelope evolution are also included. Our results based on the adiabatic mass loss model could be used to improve the binary evolution theory, the binary population synthetic method, and other related aspects. We build up the adiabatic mass loss model. In this model, two approximations are included. The first one is that the energy generation and heat flow through the stellar interior can be neglected, hence the restructuring is adiabatic. The second one is that he stellar interior remains in hydrostatic equilibrium. We model this response by constructing model sequences, beginning with a donor star filling its Roche lobe at an arbitrary point in its evolution, holding its specific entropy and composition profiles fixed. These approximations are validated by the comparison with the time-dependent binary mass transfer calculations and the polytropic model for low mass zero-age main-sequence stars. In the dynamical time scale mass transfer, the adiabatic response of the donor star drives it to expand beyond its Roche lobe, leading to runaway mass transfer and the formation of a common envelope with its companion star. For donor stars with surface convection zones of any significant depth, this runaway condition is encountered early in mass transfer, if at all; but for main sequence stars with radiative envelopes, it may be encountered after a prolonged phase of thermal time scale mass transfer, so-called delayed dynamical instability. We identify the critical binary mass ratio for the onset of dynamical time scale mass transfer; if the ratio of donor to accretor masses exceeds this critical value, the dynamical time scale mass transfer ensues. The grid of criterion for all stars can be used to be the basic input as the binary population synthetic method, which will be improved absolutely. In common envelope evolution, the dissipation of orbital energy of the binary provides the energy to eject the common envelope; the energy budget for this process essentially consists of the initial orbital energy of the binary and the initial binding energies of the binary components. We emphasize that, because stellar core and envelope contribute mutually to each other's gravitational potential energy, proper evaluation of the total energy of a star requires integration over the entire stellar interior, not the ejected envelope alone as commonly assumed. We show that the change in total energy of the donor star, as a function of its remaining mass along an adiabatic mass-loss sequence, can be calculated. This change in total energy of the donor star, combined with the requirement that both remnant donor and its companion star fit within their respective Roche lobes, then circumscribes energetically possible survivors of common envelope evolution. It is the first time that we can calculate the accurate total energy of the donor star in common envelope evolution, while the results with the old method are inconsistent with observations.

On the prediction of far field computational aeroacoustics of advanced propellers

NASA Technical Reports Server (NTRS)

Jaeger, Stephen M.; Korkan, Kenneth D.

1990-01-01

A numerical method for determining the acoustic far field generated by a high-speed subsonic aircraft propeller was developed. The approach used in this method was to generate the entire three-dimensional pressure field about the propeller (using an Euler flowfield solver) and then to apply a solution of the wave equation on a cylindrical surface enveloping the propeller. The method is applied to generate the three-dimensional flowfield between two blades of an advanced propeller. The results are compared with experimental data obtained in a wind-tunnel test at a Mach number of 0.6.

Propfan Test Assessment (PTA): Flight test report

NASA Technical Reports Server (NTRS)

Little, B. H.; Bartel, H. W.; Reddy, N. N.; Swift, G.; Withers, C. C.; Brown, P. C.

1989-01-01

The Propfan Test Assessment (PTA) aircraft was flown to obtain glade stress and noise data for a 2.74m (9 ft.) diameter single rotation propfan. Tests were performed at Mach numbers to 0.85 and altitudes to 12,192m (40,000 ft.). The propfan was well-behaved structurally over the entire flight envelope, demonstrating that the blade design technology was completely adequate. Noise data were characterized by strong signals at blade passage frequency and up to 10 harmonics. Cabin noise was not so high as to preclude attainment of comfortable levels with suitable wall treatment. Community noise was not excessive.

Generalized Courant-Snyder Theory and Kapchinskij-Vladimirskij Distribution For High-intensity Beams In A Coupled Transverse Focusing Lattice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong QIn, Ronald Davidson

2011-07-18

The Courant-Snyder (CS) theory and the Kapchinskij-Vladimirskij (KV) distribution for high-intensity beams in a uncoupled focusing lattice are generalized to the case of coupled transverse dynamics. The envelope function is generalized to an envelope matrix, and the envelope equation becomes a matrix envelope equation with matrix operations that are non-commutative. In an uncoupled lattice, the KV distribution function, first analyzed in 1959, is the only known exact solution of the nonlinear Vlasov-Maxwell equations for high-intensity beams including self-fields in a self-consistent manner. The KV solution is generalized to high-intensity beams in a coupled transverse lattice using the generalized CS invariant.more » This solution projects to a rotating, pulsating elliptical beam in transverse configuration space. The fully self-consistent solution reduces the nonlinear Vlasov-Maxwell equations to a nonlinear matrix ordinary differential equation for the envelope matrix, which determines the geometry of the pulsating and rotating beam ellipse. These results provide us with a new theoretical tool to investigate the dynamics of high-intensity beams in a coupled transverse lattice. A strongly coupled lattice, a so-called N-rolling lattice, is studied as an example. It is found that strong coupling does not deteriorate the beam quality. Instead, the coupling induces beam rotation, and reduces beam pulsation.« less

Generalized Courant-Snyder theory and Kapchinskij-Vladimirskij distribution for high-intensity beams in a coupled transverse focusing lattice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qin Hong; Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026; Davidson, Ronald C.

2011-05-15

The Courant-Snyder (CS) theory and the Kapchinskij-Vladimirskij (KV) distribution for high-intensity beams in an uncoupled focusing lattice are generalized to the case of coupled transverse dynamics. The envelope function is generalized to an envelope matrix, and the envelope equation becomes a matrix envelope equation with matrix operations that are noncommutative. In an uncoupled lattice, the KV distribution function, first analyzed in 1959, is the only known exact solution of the nonlinear Vlasov-Maxwell equations for high-intensity beams including self-fields in a self-consistent manner. The KV solution is generalized to high-intensity beams in a coupled transverse lattice using the generalized CS invariant.more » This solution projects to a rotating, pulsating elliptical beam in transverse configuration space. The fully self-consistent solution reduces the nonlinear Vlasov-Maxwell equations to a nonlinear matrix ordinary differential equation for the envelope matrix, which determines the geometry of the pulsating and rotating beam ellipse. These results provide us with a new theoretical tool to investigate the dynamics of high-intensity beams in a coupled transverse lattice. A strongly coupled lattice, a so-called N-rolling lattice, is studied as an example. It is found that strong coupling does not deteriorate the beam quality. Instead, the coupling induces beam rotation and reduces beam pulsation.« less

Limitations on the applicability of FODO lattices for electron cooling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bertsche, K.J.

1997-09-01

Assuming a KV beam distribution (a uniform distribution over an elliptical region of transverse phase space), the beam envelop equations are shown, where X and Y are the transverse beam sizes, {kappa} is the lens strength, K is the generalized beam perveance, and {epsilon} is the beam emittance. If we further assume operation in a space-charge dominated regime, the right most term can be ignored in each equation. In this case, particle flow will be laminar, and the above equations not only describe the envelope of the beam, but also the trajectory of the outermost particles.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fernando, Sudarshan; Günaydin, Murat

We study the minimal unitary representation (minrep) of SO(5, 2), obtained by quantization of its geometric quasiconformal action, its deformations and supersymmetric extensions. The minrep of SO(5, 2) describes a massless conformal scalar field in five dimensions and admits a unique “deformation” which describes a massless conformal spinor. Scalar and spinor minreps of SO(5, 2) are the 5d analogs of Dirac’s singletons of SO(3, 2). We then construct the minimal unitary representation of the unique 5d supercon-formal algebra F(4) with the even subalgebra SO(5, 2) ×SU(2). The minrep of F(4) describes a massless conformal supermultiplet consisting of two scalar andmore » one spinor fields. We then extend our results to the construction of higher spin AdS 6/CFT 5 (super)-algebras. The Joseph ideal of the minrep of SO(5, 2) vanishes identically as operators and hence its enveloping algebra yields the AdS 6/CFT 5 bosonic higher spin algebra directly. The enveloping algebra of the spinor minrep defines a “deformed” higher spin algebra for which a deformed Joseph ideal vanishes identically as operators. These results are then extended to the construction of the unique higher spin AdS 6/CFT 5 superalgebra as the enveloping algebra of the minimal unitary realization of F(4) obtained by the quasiconformal methods.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eilert, P.L.; Hoeschele, M.

This paper discussed a market-transformation program to reduce energy use in modular school classrooms, a large part of new construction activities in California's schools. Today's modular classrooms cost more to operate than is necessary to provide effective, comfortable learning conditions for students and teachers. Although past resource acquisition programs have created a demand for efficient products and services, modular classrooms remain poorly differentiated in this respect. The cost-effectiveness of a range of potential energy efficiency measures (EEM's) were evaluated including lighting, alternative HVAC options, and improved envelope features. Viable EEM's were combined in two separate packages. The first includes measuresmore » that can easily be implemented and are projected to reduce operating costs by 30%. The second implements a daylighting system, a two-stage evaporative cooler, and radiant heating, resulting in projected annual energy cost savings over 60%. Transforming the market for modular classrooms is accomplished using natural market forces, rather than financial incentives directed at an entire industry. Proactive efforts are focused on the manufacturing industry's change leaders to commercialize energy-efficient products. Lost market share and peer pressure do the heavy lifting of convincing market followers to upgrade their products. Demand for efficient classrooms is increased by educating schools about the new products' financial advantages, comfort enhancements, and environmental benefits. As new products become established in the marketplace, support will be gradually withdrawn. The relevance of this work extends beyond California, given other States' programs to reduce class size, and the Presidents initiative to reduce class size nationally.« less

A new therapeutic strategy for lengthening severe short nose.

PubMed

Rikimaru, Hideaki; Kiyokawa, Kensuke; Watanabe, Koichi; Koga, Noriyuki; Nishi, Yukiko

2010-03-01

Correction of severe short nose is a distressing problem for plastic surgeons. It is difficult to simultaneously lengthen the 3 components of the nose, which are the outer skin envelope, the framework, and the mucosal lining. We developed a new method to lengthen the nose more than 10 mm definitively and safely, which was performed using the technique of distraction osteogenesis. The procedure involves a 2-stage operation. At the first stage, boat-shaped iliac bone is grafted on the dorsum. More than 6 months later, the second-stage operation is performed. The grafted bone is cut horizontally in the center, and the distraction device is applied to it. Distraction osteogenesis is started after a latency period of 14 days and performed at a rate of 0.6 mm once daily. The distraction device is replaced by a special attachment (Ribbond; Ribbond Inc) during the 3-month consolidation period. Our method was applied for 2 patients with congenitally and posttraumatic severe short nose, respectively. The total amount of distraction osteogenesis was 12.6 and 13.8 mm, respectively. The profiles of both of the patients improved, and they were satisfied with the results. The method we developed is an entirely new approach to the correction of severe short nose. Furthermore, it was determined that nonvascularized grafted iliac bone could be lengthened by distraction osteogenesis. Our new method was a very effective and definitive technique and could become a mainstream procedure for the correction of severe short nose.

The Evolution of the Multiplicity of Embedded Protostars. II. Binary Separation Distribution and Analysis

NASA Astrophysics Data System (ADS)

Connelley, Michael S.; Reipurth, Bo; Tokunaga, Alan T.

2008-06-01

We present the Class I protostellar binary separation distribution based on the data tabulated in a companion paper. We verify the excess of Class I binary stars over solar-type main-sequence stars in the separation range from 500 AU to 4500 AU. Although our sources are in nearby star-forming regions distributed across the entire sky (including Orion), none of our objects are in a high stellar density environment. A log-normal function, used by previous authors to fit the main-sequence and T Tauri binary separation distributions, poorly fits our data, and we determine that a log-uniform function is a better fit. Our observations show that the binary separation distribution changes significantly during the Class I phase, and that the binary frequency at separations greater than 1000 AU declines steadily with respect to spectral index. Despite these changes, the binary frequency remains constant until the end of the Class I phase, when it drops sharply. We propose a scenario to account for the changes in the Class I binary separation distribution. This scenario postulates that a large number of companions with a separation greater than ~1000 AU were ejected during the Class 0 phase, but remain gravitationally bound due to the significant mass of the Class I envelope. As the envelope dissipates, these companions become unbound and the binary frequency at wide separations declines. Circumstellar and circumbinary disks are expected to play an important role in the orbital evolution at closer separations. This scenario predicts that a large number of Class 0 objects should be non-hierarchical multiple systems, and that many Class I young stellar objects (YSOs) with a widely separated companion should also have a very close companion. We also find that Class I protostars are not dynamically pristine, but have experienced dynamical evolution before they are visible as Class I objects. Our analysis shows that the Class I binary frequency and the binary separation distribution strongly depend on the star-forming environment. The Infrared Telescope Facility is operated by the University of Hawaii under Cooperative Agreement no. NCC 5-538 with the National Aeronautics and Space Administration, Science Mission Directorate, Planetary Astronomy Program. The United Kingdom Infrared Telescope is operated by the Joint Astronomy Centre on behalf of the Science and Technology Facilities Council of the U.K. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.

BUILDING ENVELOPE OPTIMIZATION USING EMERGY ANALYSIS

EPA Science Inventory

Energy analysis is an integral component of sustainable building practices. Energy analysis coupled with optimization techniques may offer solutions for greater energy efficiency over the lifetime of the building. However, all such computationsemploy the energy used for operation...

Introduction to Flight Test Engineering (Introduction aux techniques des essais en vol)

DTIC Science & Technology

2005-07-01

or aircraft parameters • Calculations in the frequency domain ( Fast Fourier Transform) • Data analysis with dedicated software for: • Signal...density Fast Fourier Transform Transfer function analysis Frequency response analysis Etc. PRESENTATION Color/black & white Display screen...envelope by operating the airplane at increasing ranges - representing increasing risk - of engine operation, airspeeds both fast and slow, altitude

Measuring the Capacity Utilization of Public District Hospitals in Tunisia: Using Dual Data Envelopment Analysis Approach.

PubMed

Arfa, Chokri; Leleu, Hervé; Goaïed, Mohamed; van Mosseveld, Cornelis

2016-06-06

Public district hospitals (PDHs) in Tunisia are not operating at full plant capacity and underutilize their operating budget. Individual PDHs capacity utilization (CU) is measured for 2000 and 2010 using dual data envelopment analysis (DEA) approach with shadow prices input and output restrictions. The CU is estimated for 101 of 105 PDH in 2000 and 94 of 105 PDH in 2010. In average, unused capacity is estimated at 18% in 2010 vs. 13% in 2000. Of PDHs 26% underutilize their operating budget in 2010 vs. 21% in 2000. Inadequate supply, health quality and the lack of operating budget should be tackled to reduce unmet user's needs and the bypassing of the PDHs and, thus to increase their CU. Social health insurance should be turned into a direct purchaser of curative and preventive care for the PDHs. © 2017 The Author(s); Published by Kerman University of Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Mixing in classical novae: a 2-D sensitivity study

NASA Astrophysics Data System (ADS)

Casanova, J.; José, J.; García-Berro, E.; Calder, A.; Shore, S. N.

2011-03-01

Context. Classical novae are explosive phenomena that take place in stellar binary systems. They are powered by mass transfer from a low-mass, main sequence star onto a white dwarf. The material piles up under degenerate conditions and a thermonuclear runaway ensues. The energy released by the suite of nuclear processes operating at the envelope heats the material up to peak temperatures of ~(1-4) × 108 K. During these events, about 10-4-10-5M⊙, enriched in CNO and other intermediate-mass elements, are ejected into the interstellar medium. To account for the gross observational properties of classical novae (in particular, a metallicity enhancement in the ejecta above solar values), numerical models assume mixing between the (solar-like) material transferred from the companion and the outermost layers (CO- or ONe-rich) of the underlying white dwarf. Aims: The nature of the mixing mechanism that operates at the core-envelope interface has puzzled stellar modelers for about 40 years. Here we investigate the role of Kelvin-Helmholtz instabilities as a natural mechanism for self-enrichment of the accreted envelope with core material. Methods: The feasibility of this mechanism is studied by means of the multidimensional code FLASH. Here, we present a series of 9 numerical simulations perfomed in two dimensions aimed at testing the possible influence of the initial perturbation (duration, strength, location, and size), the resolution adopted, or the size of the computational domain on the results. Results: We show that results do not depend substantially on the specific choice of these parameters, demonstrating that Kelvin-Helmholtz instabilities can naturally lead to self-enrichment of the accreted envelope with core material, at levels that agree with observations. Movie is only available in electronic form at http://www.aanda.org

The application of DEA (Data Envelopment Analysis) window analysis in the assessment of influence on operational efficiencies after the establishment of branched hospitals.

PubMed

Jia, Tongying; Yuan, Huiyun

2017-04-12

Many large-scaled public hospitals have established branched hospitals in China. This study is to provide evidence for strategy making on the management and development of multi-branched hospitals by evaluating and comparing the operational efficiencies of different hospitals before and after their establishment of branched hospitals. DEA (Data Envelopment Analysis) window analysis was performed on a 7-year data pool from five public hospitals provided by health authorities and institutional surveys. The operational efficiencies of sample hospitals measured in this study (including technical efficiency, pure technical efficiency and scale efficiency) had overall trends towards increase during this 7-year period of time, however, a temporary downturn occurred shortly after the establishment of branched hospitals; pure technical efficiency contributed more to the improvement of technical efficiency compared to scale efficiency. The establishment of branched-hospitals did not lead to a long-term negative effect on hospital operational efficiencies. Our data indicated the importance of improving scale efficiency via the optimization of organizational management, as well as the advantage of a different form of branch-establishment, merging and reorganization. This study brought an insight into the practical application of DEA window analysis on the assessment of hospital operational efficiencies.

Habitat classification modeling with incomplete data: Pushing the habitat envelope

USGS Publications Warehouse

Zarnetske, P.L.; Edwards, T.C.; Moisen, Gretchen G.

2007-01-01

Habitat classification models (HCMs) are invaluable tools for species conservation, land-use planning, reserve design, and metapopulation assessments, particularly at broad spatial scales. However, species occurrence data are often lacking and typically limited to presence points at broad scales. This lack of absence data precludes the use of many statistical techniques for HCMs. One option is to generate pseudo-absence points so that the many available statistical modeling tools can be used. Traditional techniques generate pseudoabsence points at random across broadly defined species ranges, often failing to include biological knowledge concerning the species-habitat relationship. We incorporated biological knowledge of the species-habitat relationship into pseudo-absence points by creating habitat envelopes that constrain the region from which points were randomly selected. We define a habitat envelope as an ecological representation of a species, or species feature's (e.g., nest) observed distribution (i.e., realized niche) based on a single attribute, or the spatial intersection of multiple attributes. We created HCMs for Northern Goshawk (Accipiter gentilis atricapillus) nest habitat during the breeding season across Utah forests with extant nest presence points and ecologically based pseudo-absence points using logistic regression. Predictor variables were derived from 30-m USDA Landfire and 250-m Forest Inventory and Analysis (FIA) map products. These habitat-envelope-based models were then compared to null envelope models which use traditional practices for generating pseudo-absences. Models were assessed for fit and predictive capability using metrics such as kappa, thresholdindependent receiver operating characteristic (ROC) plots, adjusted deviance (Dadj2), and cross-validation, and were also assessed for ecological relevance. For all cases, habitat envelope-based models outperformed null envelope models and were more ecologically relevant, suggesting that incorporating biological knowledge into pseudo-absence point generation is a powerful tool for species habitat assessments. Furthermore, given some a priori knowledge of the species-habitat relationship, ecologically based pseudo-absence points can be applied to any species, ecosystem, data resolution, and spatial extent. ?? 2007 by the Ecological Society of America.

Polyvalent Envelope Glycoprotein Vaccine Elicits a Broader Neutralizing Antibody Response but Is Unable To Provide Sterilizing Protection against Heterologous Simian/Human Immunodeficiency Virus Infection in Pigtailed Macaques

PubMed Central

Cho, Michael W.; Kim, Young B.; Lee, Myung K.; Gupta, Kailash C.; Ross, Will; Plishka, Ron; Buckler-White, Alicia; Igarashi, Tatsuhiko; Theodore, Ted; Byrum, Russ; Kemp, Chris; Montefiori, David C.; Martin, Malcolm A.

2001-01-01

The great difficulty in eliciting broadly cross-reactive neutralizing antibodies (NAbs) against human immunodeficiency virus type 1 (HIV-1) isolates has been attributed to several intrinsic properties of their viral envelope glycoprotein, including its complex quaternary structure, extensive glycosylation, and marked genetic variability. Most previously evaluated vaccine candidates have utilized envelope glycoprotein from a single virus isolate. Here we compare the breadth of NAb and protective immune response following vaccination of pigtailed macaques with envelope protein(s) derived from either single or multiple viral isolates. Animals were challenged with Simian/human immunodeficiency virus strain DH12 (SHIVDH12) following priming with recombinant vaccinia virus(es) expressing gp160(s) and boosting with gp120 protein(s) from (i) LAI, RF, 89.6, AD8, and Bal (Polyvalent); (ii) LAI, RF, 89.6, AD8, Bal, and DH12 (Polyvalent-DH12); (iii) 89.6 (Monovalent-89.6); and (iv) DH12 (Monovalent-DH12). Animals in the two polyvalent vaccine groups developed NAbs against more HIV-1 isolates than those in the two monovalent vaccine groups (P = 0.0054). However, the increased breadth of response was directed almost entirely against the vaccine strains. Resistance to SHIVDH12 strongly correlated with the level of NAbs directed against the virus on the day of challenge (P = 0.0008). Accordingly, the animals in the Monovalent-DH12 and Polyvalent-DH12 vaccine groups were more resistant to the SHIVDH12 challenge than the macaques immunized with preparations lacking a DH12 component (viz. Polyvalent and Monovalent-89.6) (P = 0.039). Despite the absence of any detectable NAb, animals in the Polyvalent vaccine group, but not those immunized with Monovalent-89.6, exhibited markedly lower levels of plasma virus than those in the control group, suggesting a superior cell-mediated immune response induced by the polyvalent vaccine. PMID:11160726

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fernando, Sudarshan; Gunaydin, Murat

Here, we extend our earlier work on the minimal unitary representation of SO(d, 2)and its deformations for d=4, 5and 6to arbitrary dimensions d. We show that there is a one-to-one correspondence between the minrep of SO(d, 2)and its deformations and massless conformal fields in Minkowskian spacetimes in ddimensions. The minrep describes a massless conformal scalar field, and its deformations describe massless conformal fields of higher spin. The generators of Joseph ideal vanish identically as operators for the quasiconformal realization of the minrep, and its enveloping algebra yields directly the standard bosonic AdS (d+1)/CFT d higher spin algebra. For deformed minrepsmore » the generators of certain deformations of Joseph ideal vanish as operators and their enveloping algebras lead to deformations of the standard bosonic higher spin algebra. In odd dimensions there is a unique deformation of the higher spin algebra corresponding to the spinor singleton. In even dimensions one finds infinitely many deformations of the higher spin algebra labelled by the eigenvalues of Casimir operator of the little group SO(d–2)for massless representations.« less

Neural coding of sound envelope in reverberant environments.

PubMed

Slama, Michaël C C; Delgutte, Bertrand

2015-03-11

Speech reception depends critically on temporal modulations in the amplitude envelope of the speech signal. Reverberation encountered in everyday environments can substantially attenuate these modulations. To assess the effect of reverberation on the neural coding of amplitude envelope, we recorded from single units in the inferior colliculus (IC) of unanesthetized rabbit using sinusoidally amplitude modulated (AM) broadband noise stimuli presented in simulated anechoic and reverberant environments. Although reverberation degraded both rate and temporal coding of AM in IC neurons, in most neurons, the degradation in temporal coding was smaller than the AM attenuation in the stimulus. This compensation could largely be accounted for by the compressive shape of the modulation input-output function (MIOF), which describes the nonlinear transformation of modulation depth from acoustic stimuli into neural responses. Additionally, in a subset of neurons, the temporal coding of AM was better for reverberant stimuli than for anechoic stimuli having the same modulation depth at the ear. Using hybrid anechoic stimuli that selectively possess certain properties of reverberant sounds, we show that this reverberant advantage is not caused by envelope distortion, static interaural decorrelation, or spectral coloration. Overall, our results suggest that the auditory system may possess dual mechanisms that make the coding of amplitude envelope relatively robust in reverberation: one general mechanism operating for all stimuli with small modulation depths, and another mechanism dependent on very specific properties of reverberant stimuli, possibly the periodic fluctuations in interaural correlation at the modulation frequency. Copyright © 2015 the authors 0270-6474/15/354452-17$15.00/0.

Developpement d'une plateforme de simulation et d'un pilote automatique - Application aux Cessna Citation X et Hawker 800XP

NASA Astrophysics Data System (ADS)

Ghazi, Georges

This report presents several methodologies for the design of tools intended to the analysis of the stability and the control of a business aircraft. At first, a generic flight dynamic model was developed to predict the behavior of the aircraft further to a movement on the control surfaces or further to any disturbance. For that purpose, different categories of winds were considered in the module of simulation to generate various scenarios and conclude about the efficiency of the autopilot. Besides being realistic, the flight model takes into account the variation of the mass parameters according to fuel consumption. A comparison with a simulator of the company CAE Inc. and certified level D allowed to validate this first stage with an acceptable success rate. Once the dynamics is validated, the next stage deals with the stability around a flight condition. For that purpose, a first static analysis is established to find the trim conditions inside the flight envelop. Then, two algorithms of linearization generate the state space models which approximate the decoupled dynamics (longitudinal and lateral) of the aircraft. Then to test the viability of the linear models, 1,500 comparisons with the nonlinear dynamics have been done with a 100% rate of success. The study of stability allowed to highlight the need of control systems to improve first the performances of the plane, then to control its different axes. A methodology based on a coupling between a modern control technique (LQR) and a genetic algorithm is presented. This methodology allowed to find optimal and successful controllers which satisfy a large number of specifications. Besides being successful, they have to be robust to uncertainties owed to the variation of mass. Thus, an analysis of robustness using the theory of the guardian maps was applied to uncertain dynamics. However, because of a too sensitive region of the flight envelop, some analyses are biased. Nevertheless, a validation with the nonlinear dynamics allowed to prove the robustness of the controllers over the entire flight envelope. Finally, the last stage of this project concerned the control laws for the autopilot. Once again, the proposed methodology, bases itself on the association of flight mechanic equations, control theory and a metaheuristic optimization method. Afterward, four detailed test scenarios are presented to illustrate the efficiency and the robustness of the entire autopilot.

Derated ion thruster design issues

NASA Technical Reports Server (NTRS)

Patterson, Michael J.; Rawlin, Vincent K.

1991-01-01

Preliminary activities to develop and refine a lightweight 30 cm engineering model ion thruster are discussed. The approach is to develop a 'derated' ion thruster capable of performing both auxiliary and primary propulsion roles over an input power range of at least 0.5 to 5.0 kilo-W. Design modifications to a baseline thruster to reduce mass and volume are discussed. Performance data over an order of magnitude input power range are presented, with emphasis on the performance impact of engine throttling. Thruster design modifications to optimize performance over specific power envelopes are discussed. Additionally, lifetime estimates based on wear test measurements are made for the operation envelope of the engine.

A 10-MWe solar-thermal central-receiver pilot plant: Solar facilities design integration. Plant operating/training manual (RADL-Item 2-36)

NASA Astrophysics Data System (ADS)

1982-07-01

Plant and system level operating instructions are provided for the Barstow Solar Pilot Plant. Individual status instructions are given that identify plant conditions, process controller responsibilities, process conditions and control accuracies, operating envelopes, and operator cautions appropriate to the operating condition. Transition operating instructions identify the sequence of activities to be carried out to accomplish the indicated transition. Most transitions involve the startup or shutdown of an individual flowpath. Background information is provided on collector field operations, and the heliostat groupings and specific commands used in support receiver startup are defined.

Aircraft loss-of-control prevention and recovery: A hybrid control strategy

NASA Astrophysics Data System (ADS)

Dongmo, Jean-Etienne Temgoua

The Complexity of modern commercial and military aircrafts has necessitated better protection and recovery systems. With the tremendous advances in computer technology, control theory and better mathematical models, a number of issues (Prevention, Reconfiguration, Recovery, Operation near critical points, ... etc) moderately addressed in the past have regained interest in the aeronautical industry. Flight envelope is essential in all flying aerospace vehicles. Typically, flying the vehicle means remaining within the flight envelope at all times. Operation outside the normal flight regime is usually subject to failure of components (Actuators, Engines, Deflection Surfaces) , pilots's mistakes, maneuverability near critical points and environmental conditions (crosswinds...) and in general characterized as Loss-Of-Control (LOC) because the aircraft no longer responds to pilot's inputs as expected. For the purpose of this work, (LOC) in aircraft is defined as the departure from the safe set (controlled flight) recognized as the maximum controllable (reachable) set in the initial flight envelope. The LOC can be reached either through failure, unintended maneuvers, evolution near irregular points and disturbances. A coordinated strategy is investigated and designed to ensure that the aircraft can maneuver safely in their constraint domain and can also recover from abnormal regime. The procedure involves the computation of the largest controllable (reachable) set (Safe set) contained in the initial prescribed envelope. The problem is posed as a reachability problem using Hamilton-Jacobi Partial Differential Equation (HJ-PDE) where a cost function is set to he minimized along trajectory departing from the given set. Prevention is then obtained by computing the controller which would allow the flight vehicle to remain in the maximum controlled set in a multi-objective set up. Then the recovery procedure is illustrated with a two-point boundary value problem. Once illustrate, a set of control strategies is designed for recovery purpose ranging from nonlinear smooth regulators with Hamilton Jacobi-Hellman (HJB) formulation to the switching controllers with High Order Sliding Mode Controllers (HOSMC). A coordinated strategy known as a high level supervisor is then implemented using the multi-models concept where models operate in specified safe regions of the state space.

Operative air temperature data for different measures applied on a building envelope in warm climate.

PubMed

Baglivo, Cristina; Congedo, Paolo Maria

2018-04-01

Several technical combinations have been evaluated in order to design high energy performance buildings for the warm climate. The analysis has been developed in several steps, avoiding the use of HVAC systems. The methodological approach of this study is based on a sequential search technique and it is shown on the paper entitled "Envelope Design Optimization by Thermal Modeling of a Building in a Warm Climate" [1]. The Operative Air Temperature trends (TOP), for each combination, have been plotted through a dynamic simulation performed using the software TRNSYS 17 (a transient system simulation program, University of Wisconsin, Solar Energy Laboratory, USA, 2010). Starting from the simplest building configuration consisting of 9 rooms (equal-sized modules of 5 × 5 m 2 ), the different building components are sequentially evaluated until the envelope design is optimized. The aim of this study is to perform a step-by-step simulation, simplifying as much as possible the model without making additional variables that can modify their performances. Walls, slab-on-ground floor, roof, shading and windows are among the simulated building components. The results are shown for each combination and evaluated for Brindisi, a city in southern Italy having 1083 degrees day, belonging to the national climatic zone C. The data show the trends of the TOP for each measure applied in the case study for a total of 17 combinations divided into eight steps.

Resonant beam behavior studies in the Proton Storage Ring

NASA Astrophysics Data System (ADS)

Cousineau, S.; Holmes, J.; Galambos, J.; Fedotov, A.; Wei, J.; Macek, R.

2003-07-01

We present studies of space-charge-induced beam profile broadening at high intensities in the Proton Storage Ring (PSR) at Los Alamos National Laboratory. We investigate the profile broadening through detailed particle-in-cell simulations of several experiments and obtain results in good agreement with the measurements. We interpret these results within the framework of coherent resonance theory. With increasing intensity, our simulations show strong evidence for the presence of a quadrupole-mode resonance of the beam envelope with the lattice in the vertical plane. Specifically, we observe incoherent tunes crossing integer values, and large amplitude, nearly periodic envelope oscillations. At the highest operating intensities, we observe a continuing relaxation of the beam through space charge forces leading to emittance growth. The increase of emittance commences when the beam parameters encounter an envelope stop band. Once the stop band is reached, the emittance growth balances the intensity increase to maintain the beam near the stop band edge. Additionally, we investigate the potential benefit of a stop band correction to the high intensity PSR beam.

A Performance Map for Ideal Air Breathing Pulse Detonation Engines

NASA Technical Reports Server (NTRS)

Paxson, Daniel E.

2001-01-01

The performance of an ideal, air breathing Pulse Detonation Engine is described in a manner that is useful for application studies (e.g., as a stand-alone, propulsion system, in combined cycles, or in hybrid turbomachinery cycles). It is shown that the Pulse Detonation Engine may be characterized by an averaged total pressure ratio, which is a unique function of the inlet temperature, the fraction of the inlet flow containing a reacting mixture, and the stoichiometry of the mixture. The inlet temperature and stoichiometry (equivalence ratio) may in turn be combined to form a nondimensional heat addition parameter. For each value of this parameter, the average total enthalpy ratio and total pressure ratio across the device are functions of only the reactant fill fraction. Performance over the entire operating envelope can thus be presented on a single plot of total pressure ratio versus total enthalpy ratio for families of the heat addition parameter. Total pressure ratios are derived from thrust calculations obtained from an experimentally validated, reactive Euler code capable of computing complete Pulse Detonation Engine limit cycles. Results are presented which demonstrate the utility of the described method for assessing performance of the Pulse Detonation Engine in several potential applications. Limitations and assumptions of the analysis are discussed. Details of the particular detonative cycle used for the computations are described.

Sound representation in higher language areas during language generation

PubMed Central

Magrassi, Lorenzo; Aromataris, Giuseppe; Cabrini, Alessandro; Annovazzi-Lodi, Valerio; Moro, Andrea

2015-01-01

How language is encoded by neural activity in the higher-level language areas of humans is still largely unknown. We investigated whether the electrophysiological activity of Broca’s area correlates with the sound of the utterances produced. During speech perception, the electric cortical activity of the auditory areas correlates with the sound envelope of the utterances. In our experiment, we compared the electrocorticogram recorded during awake neurosurgical operations in Broca’s area and in the dominant temporal lobe with the sound envelope of single words versus sentences read aloud or mentally by the patients. Our results indicate that the electrocorticogram correlates with the sound envelope of the utterances, starting before any sound is produced and even in the absence of speech, when the patient is reading mentally. No correlations were found when the electrocorticogram was recorded in the superior parietal gyrus, an area not directly involved in language generation, or in Broca’s area when the participants were executing a repetitive motor task, which did not include any linguistic content, with their dominant hand. The distribution of suprathreshold correlations across frequencies of cortical activities varied whether the sound envelope derived from words or sentences. Our results suggest the activity of language areas is organized by sound when language is generated before any utterance is produced or heard. PMID:25624479

Linearized Poststall Aerodynamic and Control Law Models of the X-31A Aircraft and Comparison with Flight Data

NASA Technical Reports Server (NTRS)

Stoliker, Patrick C.; Bosworth, John T.; Georgie, Jennifer

1997-01-01

The X-31A aircraft has a unique configuration that uses thrust-vector vanes and aerodynamic control effectors to provide an operating envelope to a maximum 70 deg angle of attack, an inherently nonlinear portion of the flight envelope. This report presents linearized versions of the X-31A longitudinal and lateral-directional control systems, with aerodynamic models sufficient to evaluate characteristics in the poststall envelope at 30 deg, 45 deg, and 60 deg angle of attack. The models are presented with detail sufficient to allow the reader to reproduce the linear results or perform independent control studies. Comparisons between the responses of the linear models and flight data are presented in the time and frequency domains to demonstrate the strengths and weaknesses of the ability to predict high-angle-of-attack flight dynamics using linear models. The X-31A six-degree-of-freedom simulation contains a program that calculates linear perturbation models throughout the X-31A flight envelope. The models include aerodynamics and flight control system dynamics that are used for stability, controllability, and handling qualities analysis. The models presented in this report demonstrate the ability to provide reasonable linear representations in the poststall flight regime.

Processing of high-precision ceramic balls with a spiral V-groove plate

NASA Astrophysics Data System (ADS)

Feng, Ming; Wu, Yongbo; Yuan, Julong; Ping, Zhao

2017-03-01

As the demand for high-performance bearings gradually increases, ceramic balls with excellent properties, such as high accuracy, high reliability, and high chemical durability used, are extensively used for highperformance bearings. In this study, a spiral V-groove plate method is employed in processing high-precision ceramic balls. After the kinematic analysis of the ball-spin angle and enveloped lapping trajectories, an experimental rig is constructed and experiments are conducted to confirm the feasibility of this method. Kinematic analysis results indicate that the method not only allows for the control of the ball-spin angle but also uniformly distributes the enveloped lapping trajectories over the entire ball surface. Experimental results demonstrate that the novel spiral Vgroove plate method performs better than the conventional concentric V-groove plate method in terms of roundness, surface roughness, diameter difference, and diameter decrease rate. Ceramic balls with a G3-level accuracy are achieved, and their typical roundness, minimum surface roughness, and diameter difference are 0.05, 0.0045, and 0.105 μm, respectively. These findings confirm that the proposed method can be applied to high-accuracy and high-consistency ceramic ball processing.

Hot subdwarfs in (eclipsing) binaries with brown dwarf or low-mass main-sequence companions

NASA Astrophysics Data System (ADS)

Schaffenroth, Veronika; Geier, Stephan; Heber, Uli

2014-09-01

The formation of hot subdwarf stars (sdBs), which are core helium-burning stars located on the extended horizontal branch, is not yet understood. Many of the known hot subdwarf stars reside in close binary systems with short orbital periods of between a few hours and a few days, with either M-star or white-dwarf companions. Common-envelope ejection is the most probable formation channel. Among these, eclipsing systems are of special importance because it is possible to constrain the parameters of both components tightly by combining spectroscopic and light-curve analyses. They are called HW Virginis systems. Soker (1998) proposed that planetary or brown-dwarf companions could cause the mass loss necessary to form an sdB. Substellar objects with masses greater than >10 M_J were predicted to survive the common-envelope phase and end up in a close orbit around the stellar remnant, while planets with lower masses would entirely evaporate. This raises the question if planets can affect stellar evolution. Here we report on newly discovered eclipsing or not eclipsing hot subdwarf binaries with brown-dwarf or low-mass main-sequence companions and their spectral and photometric analysis to determine the fundamental parameters of both components.

A Tyrosine-Based Trafficking Motif of the Tegument Protein pUL71 Is Crucial for Human Cytomegalovirus Secondary Envelopment.

PubMed

Dietz, Andrea N; Villinger, Clarissa; Becker, Stefan; Frick, Manfred; von Einem, Jens

2018-01-01

The human cytomegalovirus (HCMV) tegument protein pUL71 is required for efficient secondary envelopment and accumulates at the Golgi compartment-derived viral assembly complex (vAC) during infection. Analysis of various C-terminally truncated pUL71 proteins fused to enhanced green fluorescent protein (eGFP) identified amino acids 23 to 34 as important determinants for its Golgi complex localization. Sequence analysis and mutational verification revealed the presence of an N-terminal tyrosine-based trafficking motif (YXXΦ) in pUL71. This led us to hypothesize a requirement of the YXXΦ motif for the function of pUL71 in infection. Mutation of both the tyrosine residue and the entire YXXΦ motif resulted in an altered distribution of mutant pUL71 at the plasma membrane and in the cytoplasm during infection. Both YXXΦ mutant viruses exhibited similarly decreased focal growth and reduced virus yields in supernatants. Ultrastructurally, mutant-virus-infected cells exhibited impaired secondary envelopment manifested by accumulations of capsids undergoing an envelopment process. Additionally, clusters of capsid accumulations surrounding the vAC were observed, similar to the ultrastructural phenotype of a UL71-deficient mutant. The importance of endocytosis and thus the YXXΦ motif for targeting pUL71 to the Golgi complex was further demonstrated when clathrin-mediated endocytosis was inhibited either by coexpression of the C-terminal part of cellular AP180 (AP180-C) or by treatment with methyl-β-cyclodextrin. Both conditions resulted in a plasma membrane accumulation of pUL71. Altogether, these data reveal the presence of a functional N-terminal endocytosis motif that is an important determinant for intracellular localization of pUL71 and that is furthermore required for the function of pUL71 during secondary envelopment of HCMV capsids at the vAC. IMPORTANCE Human cytomegalovirus (HCMV) is the leading cause of birth defects among congenital virus infections and can lead to life-threatening infections in immunocompromised hosts. Current antiviral treatments target viral genome replication and are increasingly overcome by viral mutations. Therefore, identifying new targets for antiviral therapy is important for future development of novel treatment options. A detailed molecular understanding of the complex virus morphogenesis will identify potential viral as well as cellular targets for antiviral intervention. Secondary envelopment is an important viral process through which infectious virus particles are generated and which involves the action of several viral proteins, such as tegument protein pUL71. Targeting of pUL71 to the site of secondary envelopment appears to be crucial for its function during this process and is regulated by utilizing host trafficking mechanisms that are commonly exploited by viral glycoproteins. Thus, intracellular trafficking, if targeted, might present a novel target for antiviral therapy. Copyright © 2017 American Society for Microbiology.

Dredge-up and Envelope Burning in Intermediate-Mass Giants of Very Low Metallicity

NASA Astrophysics Data System (ADS)

Herwig, Falk

2004-04-01

The evolution of intermediate-mass stars at very low metallicity during their final thermal pulse asymptotic giant branch (AGB) phase is studied in detail. As representative examples, models with initial masses of 4 and 5Msolar and with a metallicity of Z=0.0001 ([Fe/H]~-2.3) are discussed. The one-dimensional stellar structure and evolution model includes time- and depth-dependent overshooting motivated by hydrodynamic simulations, as well as a full nuclear network and time-dependent mixing. Particular attention is given to high time and space resolution to avoid numerical artifacts related to third dredge-up and hot bottom burning predictions. The model calculations predict very efficient third dredge-up that mixes the envelope with the entire intershell layer or a large fraction thereof and in some cases penetrates into the C/O core below the He shell. In all cases primary oxygen is mixed into the envelope. The models predict efficient envelope burning during the interpulse phase. Depending on the envelope-burning temperature, oxygen is destroyed to varying degrees. The combined effect of dredge-up and envelope burning does not lead to any significant oxygen depletion in any of the cases considered in this study. The large dredge-up efficiency in our model is closely related to the particular properties of the H shell during the dredge-up phase in low-metallicity very metal-poor stars, which is followed here over many thermal pulses. During the dredge-up phase, the temperature just below the convective boundary is large enough for protons to burn vigorously when they are brought into the C-rich environment below the convection boundary by the time- and depth-dependent overshooting. H-burning luminosities of 105 to ~2×106Lsolar are generated. C, and to lesser degree O, is transformed into N in this dredge-up overshooting layer and enters the envelope. The global effect on the CNO abundance is similar to that of hot bottom burning. If the overshoot efficiency is larger, then dredge-up H burning causes a further increase in the dredge-up efficiency. After some thermal pulses, the dredge-up proceeds through the He shell and into the CO core beneath. Then neutrons may not be released from 13C in radiative conditions during the interpulse phase because of the scarcity of α-particles for the 13C(α,n)16O reactions. Conditions for the s-process are discussed qualitatively. The abundance evolution of H, He, C, N, O, and Na is described. Finally, the model predictions for sodium and oxygen are compared with observed abundances. The notion that massive AGB stars are the origin of the O-Na abundance anticorrelation in globular cluster giants is not consistent with the model predictions of this study. The abundance of the C-rich extremely metal-poor binaries LP 625-44, CS 29497-030, and HE 0024-2523 is discussed.

Efficiency assessment of wastewater treatment plants: A data envelopment analysis approach integrating technical, economic, and environmental issues.

PubMed

Castellet, Lledó; Molinos-Senante, María

2016-02-01

The assessment of the efficiency of wastewater treatment plants (WWTPs) is essential to compare their performance and consequently to identify the best operational practices that can contribute to the reduction of operational costs. Previous studies have evaluated the efficiency of WWTPs using conventional data envelopment analysis (DEA) models. Most of these studies have considered the operational costs of the WWTPs as inputs, while the pollutants removed from wastewater are treated as outputs. However, they have ignored the fact that each pollutant removed by a WWTP involves a different environmental impact. To overcome this limitation, this paper evaluates for the first time the efficiency of a sample of WWTPs by applying the weighted slacks-based measure model. It is a non-radial DEA model which allows assigning weights to the inputs and outputs according their importance. Thus, the assessment carried out integrates environmental issues with the traditional "techno-economic" efficiency assessment of WWTPs. Moreover, the potential economic savings for each cost item have been quantified at a plant level. It is illustrated that the WWTPs analyzed have significant room to save staff and energy costs. Several managerial implications to help WWTPs' operators make informed decisions were drawn from the methodology and empirical application carried out. Copyright © 2015 Elsevier Ltd. All rights reserved.

Studies of inactivation mechanism of non-enveloped icosahedral virus by a visible ultrashort pulsed laser

PubMed Central

2014-01-01

Background Low-power ultrashort pulsed (USP) lasers operating at wavelengths of 425 nm and near infrared region have been shown to effectively inactivate viruses such as human immunodeficiency virus (HIV), M13 bacteriophage, and murine cytomegalovirus (MCMV). It was shown previously that non-enveloped, helical viruses such as M13 bacteriophage, were inactivated by a USP laser through an impulsive stimulated Raman scattering (ISRS) process. Recently, enveloped virus like MCMV has been shown to be inactivated by a USP laser via protein aggregation induced by an ISRS process. However, the inactivation mechanism for a clinically important class of viruses – non-enveloped, icosahedral viruses remains unknown. Results and discussions We have ruled out the following four possible inactivation mechanisms for non-enveloped, icosahedral viruses, namely, (1) inactivation due to ultraviolet C (UVC) photons produced by non-linear optical process of the intense, fundamental laser beam at 425 nm; (2) inactivation caused by thermal heating generated by the direct laser absorption/heating of the virion; (3) inactivation resulting from a one-photon absorption process via chromophores such as porphyrin molecules, or indicator dyes, potentially producing reactive oxygen or other species; (4) inactivation by the USP lasers in which the extremely intense laser pulse produces shock wave-like vibrations upon impact with the viral particle. We present data which support that the inactivation mechanism for non-enveloped, icosahedral viruses is the impulsive stimulated Raman scattering process. Real-time PCR experiments show that, within the amplicon size of 273 bp tested, there is no damage on the genome of MNV-1 caused by the USP laser irradiation. Conclusion We conclude that our model non-enveloped virus, MNV-1, is inactivated by the ISRS process. These studies provide fundamental knowledge on photon-virus interactions on femtosecond time scales. From the analysis of the transmission electron microscope (TEM) images of viral particles before and after USP laser irradiation, the locations of weak structural links on the capsid of MNV-1 were revealed. This important information will greatly aid our understanding of the structure of non-enveloped, icosahedral viruses. We envision that this non-invasive, efficient viral eradication method will find applications in the disinfection of pharmaceuticals, biologicals and blood products in the near future. PMID:24495489

Exergy Analysis and Operational Efficiency of a Horizontal Ground Source Heat Pump System Operated in a Low-Energy Test House under Simulated Occupancy Conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ally, Moonis Raza; Baxter, Van D; Munk, Jeffrey D

2012-01-01

This paper presents data, analyses, measures of performance, and conclusions for a ground-source heat pump (GSHP) providing space conditioning to a 345m2 house whose envelope is made of structural insulated panels (SIP). The entire thermal load of this SIP house with RSI-3.7 (RUS-21) walls, triple pane windows with a U-factor of 1.64 W/m2 K (0.29 Btu/h ft2 oF) and solar heat gain coefficient (SHGC) of 0.25, a roof assembly with overall thermal resistance of about RSI-8.8 (RUS-50) and low leakage rates of 0.74 ACH at 50Pa was satisfied with a 2.16-Ton (7.56 kW) GSHP unit consuming negligible (9.83kWh) auxiliary heatmore » during peak winter season. The highest and lowest heating COP achieved was 4.90 (October) and 3.44 (February), respectively. The highest and lowest cooling COP achieved was 6.09 (April) and 3.88 (August). These COPs are calculated on the basis of the total power input (including duct, ground loop, and control power losses ). The second Law (Exergy) analysis provides deep insight into how systemic inefficiencies are distributed among the various GSHP components. Opportunities for design and further performance improvements are identified. Through Exergy analysis we provide a true measure of how closely actual performance approaches the ideal, and it unequivocally identifies, better than energy analysis does, the sources and causes of lost work, the root cause of system inefficiencies.« less

Rolling element bearing defect diagnosis under variable speed operation through angle synchronous averaging of wavelet de-noised estimate

NASA Astrophysics Data System (ADS)

Mishra, C.; Samantaray, A. K.; Chakraborty, G.

2016-05-01

Rolling element bearings are widely used in rotating machines and their faults can lead to excessive vibration levels and/or complete seizure of the machine. Under special operating conditions such as non-uniform or low speed shaft rotation, the available fault diagnosis methods cannot be applied for bearing fault diagnosis with full confidence. Fault symptoms in such operating conditions cannot be easily extracted through usual measurement and signal processing techniques. A typical example is a bearing in heavy rolling mill with variable load and disturbance from other sources. In extremely slow speed operation, variation in speed due to speed controller transients or external disturbances (e.g., varying load) can be relatively high. To account for speed variation, instantaneous angular position instead of time is used as the base variable of signals for signal processing purposes. Even with time synchronous averaging (TSA) and well-established methods like envelope order analysis, rolling element faults in rolling element bearings cannot be easily identified during such operating conditions. In this article we propose to use order tracking on the envelope of the wavelet de-noised estimate of the short-duration angle synchronous averaged signal to diagnose faults in rolling element bearing operating under the stated special conditions. The proposed four-stage sequential signal processing method eliminates uncorrelated content, avoids signal smearing and exposes only the fault frequencies and its harmonics in the spectrum. We use experimental data1

Performance and loads data from an outdoor hover test of a Lynx tail rotor

NASA Technical Reports Server (NTRS)

Signor, David B.; Yamauchi, Gloria K.; Smith, Charles A.; Hagen, Martin J.

1989-01-01

A Lynx tail rotor was tested in hover at the Outdoor Aerodynamic Research Facility at NASA Ames Research Center. The test objectives were to measure the isolated rotor performance to provide a baseline for subsequent testing, and to operate the rotor throughout the speed and collective envelope before testing in the NFAC 40- by 80-Foot Wind Tunnel. Rotor forces and blade bending moments were measured at ambient wind conditions from zero to 6.23 m/sec. The test envelope was limited to rotor speeds of 1550 to 1850 rpm and minus 13 deg to plus 20 deg of blade collective pitch. The isolated rotor performance and blade loads data are presented.

Determination of densified biomass mass properties using 3D laser scanning and image analysis

USDA-ARS?s Scientific Manuscript database

Biomass densification is viewed as the indispensable feedstock preprocessing operation for efficient transport, storage, material flow through machines, and handling activities. Accurate mass properties of densified biomass such as surface area, volume, and envelope density form fundamental data for...

On-Line Mu Method for Robust Flutter Prediction in Expanding a Safe Flight Envelope for an Aircraft Model Under Flight Test

NASA Technical Reports Server (NTRS)

Lind, Richard C. (Inventor); Brenner, Martin J.

2001-01-01

A structured singular value (mu) analysis method of computing flutter margins has robust stability of a linear aeroelastic model with uncertainty operators (Delta). Flight data is used to update the uncertainty operators to accurately account for errors in the computed model and the observed range of aircraft dynamics of the aircraft under test caused by time-varying aircraft parameters, nonlinearities, and flight anomalies, such as test nonrepeatability. This mu-based approach computes predict flutter margins that are worst case with respect to the modeling uncertainty for use in determining when the aircraft is approaching a flutter condition and defining an expanded safe flight envelope for the aircraft that is accepted with more confidence than traditional methods that do not update the analysis algorithm with flight data by introducing mu as a flutter margin parameter that presents several advantages over tracking damping trends as a measure of a tendency to instability from available flight data.

Evaluation of operating room suite efficiency in the Veterans Health Administration system by using data-envelopment analysis.

PubMed

Basson, Marc D; Butler, Timothy

2006-11-01

Operating room (OR) activity transcends single ratios such as cases/room, but weighting multiple inputs and outputs may be arbitrary. Data-envelopment analysis (DEA) is a novel technique by which each facility is analyzed by the weightings that optimize its score. We performed DEA analysis of 23 Veterans Health Administration annual OR activity; 87,180 cases were performed, 24 publications generated, and 560 trainee-years of education delivered, in 168 ORs over 166,377 hours by 1,384 full-time equivalents of surgical and anesthesia providers and 523 nonproviders. Varying analyzed parameters produced similar efficiency rankings, with individual differences suggesting possible inefficiencies. We characterized returns to scale for efficient sites, suggesting whether patient flow might be efficiently further increased through these sites. We matched inefficient sites to similar efficient sites for comparison and suggested resource alterations to increase efficiency. Broader DEA application might characterize OR efficiency more informatively than conventional single-ratio rank ordering.

Applications of rigged Hilbert spaces in quantum mechanics and signal processing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Celeghini, E., E-mail: celeghini@fi.infn.it; Departamento de Física Teórica, Atómica y Óptica and IMUVA, Universidad de Valladolid, Paseo Belén 7, 47011 Valladolid; Gadella, M., E-mail: manuelgadella1@gmail.com

Simultaneous use of discrete and continuous bases in quantum systems is not possible in the context of Hilbert spaces, but only in the more general structure of rigged Hilbert spaces (RHS). In addition, the relevant operators in RHS (but not in Hilbert space) are a realization of elements of a Lie enveloping algebra and support representations of semigroups. We explicitly construct here basis dependent RHS of the line and half-line and relate them to the universal enveloping algebras of the Weyl-Heisenberg algebra and su(1, 1), respectively. The complete sub-structure of both RHS and of the operators acting on them ismore » obtained from their algebraic structures or from the related fractional Fourier transforms. This allows us to describe both quantum and signal processing states and their dynamics. Two relevant improvements are introduced: (i) new kinds of filters related to restrictions to subspaces and/or the elimination of high frequency fluctuations and (ii) an operatorial structure that, starting from fix objects, describes their time evolution.« less

Complete analog control of the carrier-envelope-phase of a high-power laser amplifier.

PubMed

Feng, C; Hergott, J-F; Paul, P-M; Chen, X; Tcherbakoff, O; Comte, M; Gobert, O; Reduzzi, M; Calegari, F; Manzoni, C; Nisoli, M; Sansone, G

2013-10-21

In this work we demonstrate the development of a complete analog feedback loop for the control of the carrier-envelope phase (CEP) of a high-average power (20 W) laser operating at 10 kHz repetition rate. The proposed method combines a detection scheme working on a single-shot basis at the full-repetition-rate of the laser system with a fast actuator based either on an acousto-optic or on an electro-optic crystal. The feedback loop is used to correct the CEP fluctuations introduced by the amplification process demonstrating a CEP residual noise of 320 mrad measured on a single-shot basis. The comparison with a feedback loop operating at a lower sampling rate indicates an improvement up to 45% in the residual noise. The measurement of the CEP drift for different integration times clearly evidences the importance of the single-shot characterization of the residual CEP drift. The demonstrated scheme could be efficiently applied for systems approaching the 100 kHz repetition rate regime.

Massless conformal fields, AdS (d+1)/CFT d higher spin algebras and their deformations

DOE PAGES

Fernando, Sudarshan; Gunaydin, Murat

2016-02-04

Here, we extend our earlier work on the minimal unitary representation of SO(d, 2)and its deformations for d=4, 5and 6to arbitrary dimensions d. We show that there is a one-to-one correspondence between the minrep of SO(d, 2)and its deformations and massless conformal fields in Minkowskian spacetimes in ddimensions. The minrep describes a massless conformal scalar field, and its deformations describe massless conformal fields of higher spin. The generators of Joseph ideal vanish identically as operators for the quasiconformal realization of the minrep, and its enveloping algebra yields directly the standard bosonic AdS (d+1)/CFT d higher spin algebra. For deformed minrepsmore » the generators of certain deformations of Joseph ideal vanish as operators and their enveloping algebras lead to deformations of the standard bosonic higher spin algebra. In odd dimensions there is a unique deformation of the higher spin algebra corresponding to the spinor singleton. In even dimensions one finds infinitely many deformations of the higher spin algebra labelled by the eigenvalues of Casimir operator of the little group SO(d–2)for massless representations.« less

Variable camber rotor study

NASA Technical Reports Server (NTRS)

Dadone, L.; Cowan, J.; Mchugh, F. J.

1982-01-01

Deployment of variable camber concepts on helicopter rotors was analytically assessed. It was determined that variable camber extended the operating range of helicopters provided that the correct compromise can be obtained between performance/loads gains and mechanical complexity. A number of variable camber concepts were reviewed on a two dimensional basis to determine the usefulness of leading edge, trailing edge and overall camber variation schemes. The most powerful method to vary camber was through the trailing edge flaps undergoing relatively small motions (-5 deg to +15 deg). The aerodynamic characteristics of the NASA/Ames A-1 airfoil with 35% and 50% plain trailing edge flaps were determined by means of current subcritical and transonic airfoil design methods and used by rotor performance and loads analysis codes. The most promising variable camber schedule reviewed was a configuration with a 35% plain flap deployment in an on/off mode near the tip of a blade. Preliminary results show approximately 11% reduction in power is possible at 192 knots and a rotor thrust coefficient of 0.09. The potential demonstrated indicates a significant potential for expanding the operating envelope of the helicopter. Further investigation into improving the power saving and defining the improvement in the operational envelope of the helicopter is recommended.

Simulating Operation of a Large Turbofan Engine

NASA Technical Reports Server (NTRS)

Litt, Jonathan S.; Frederick, Dean K.; DeCastro, Jonathan

2008-01-01

The Commercial Modular Aero- Propulsion System Simulation (C-MAPSS) is a computer program for simulating transient operation of a commercial turbofan engine that can generate as much as 90,000 lb (.0.4 MN) of thrust. It includes a power-management system that enables simulation of open- or closed-loop engine operation over a wide range of thrust levels throughout the full range of flight conditions. C-MAPSS provides the user with a set of tools for performing open- and closed-loop transient simulations and comparison of linear and non-linear models throughout its operating envelope, in an easy-to-use graphical environment.

Phase-locked tracking loops for LORAN-C

NASA Technical Reports Server (NTRS)

Burhans, R. W.

1978-01-01

Portable battery operated LORAN-C receivers were fabricated to evaluate simple envelope detector methods with hybrid analog to digital phase locked loop sensor processors. The receivers are used to evaluate LORAN-C in general aviation applications. Complete circuit details are given for the experimental sensor and readout system.

14 CFR 25.907 - Propeller vibration and fatigue.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) The applicant must determine the magnitude of the propeller vibration stresses or loads, including any stress peaks and resonant conditions, throughout the operational envelope of the airplane by either: (1) Measurement of stresses or loads through direct testing or analysis based on direct testing of the propeller...

14 CFR 25.907 - Propeller vibration and fatigue.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) The applicant must determine the magnitude of the propeller vibration stresses or loads, including any stress peaks and resonant conditions, throughout the operational envelope of the airplane by either: (1) Measurement of stresses or loads through direct testing or analysis based on direct testing of the propeller...

77 FR 15183 - Agency Information Collection Activities; Extension of a Currently-Approved Information...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-14

... forwarders, property brokers, and certain Mexico-domiciled motor carriers to register their operations with... we received your comments, please include a self-addressed, stamped envelope or postcard, or print..., freight forwarders, brokers, and certain Mexico-domiciled. Estimated Number of Respondents: 37,239...

14 CFR 25.907 - Propeller vibration and fatigue.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) The applicant must determine the magnitude of the propeller vibration stresses or loads, including any stress peaks and resonant conditions, throughout the operational envelope of the airplane by either: (1) Measurement of stresses or loads through direct testing or analysis based on direct testing of the propeller...

47 CFR 97.317 - Standards for certification of external RF power amplifiers.

Code of Federal Regulations, 2010 CFR

2010-10-01

... amplifier is operated at the lesser of 1.5 kW PEP or its full output power and when the amplifier is placed... peak envelope power or mean power. (3) Exhibit no amplification (0 dB gain) between 26 MHz and 28 MHz...

47 CFR 97.317 - Standards for certification of external RF power amplifiers.

Code of Federal Regulations, 2012 CFR

2012-10-01

... amplifier is operated at the lesser of 1.5 kW PEP or its full output power and when the amplifier is placed... peak envelope power or mean power. (3) Exhibit no amplification (0 dB gain) between 26 MHz and 28 MHz...

47 CFR 97.317 - Standards for certification of external RF power amplifiers.

Code of Federal Regulations, 2014 CFR

2014-10-01

... amplifier is operated at the lesser of 1.5 kW PEP or its full output power and when the amplifier is placed... peak envelope power or mean power. (3) Exhibit no amplification (0 dB gain) between 26 MHz and 28 MHz...

47 CFR 97.317 - Standards for certification of external RF power amplifiers.

Code of Federal Regulations, 2011 CFR

2011-10-01

... amplifier is operated at the lesser of 1.5 kW PEP or its full output power and when the amplifier is placed... peak envelope power or mean power. (3) Exhibit no amplification (0 dB gain) between 26 MHz and 28 MHz...

47 CFR 97.317 - Standards for certification of external RF power amplifiers.

Code of Federal Regulations, 2013 CFR

2013-10-01

... amplifier is operated at the lesser of 1.5 kW PEP or its full output power and when the amplifier is placed... peak envelope power or mean power. (3) Exhibit no amplification (0 dB gain) between 26 MHz and 28 MHz...

Manned-Unmanned Teaming: Expanding the Envelope of UAS Operational Employment (Reprint)

DTIC Science & Technology

2014-11-01

Orders will be expedited if placed through the librarian or other person designated to request documents from DTIC. Change of Address Organizations...within the domain of the aeromedical community. There are many lines of scientifi c inves- tigation among multiple consortia of research entities

Mass return to the interstellar medium from highly-evolved carbon stars

NASA Technical Reports Server (NTRS)

Latter, W. B.; Thronson, H. A., Jr.; Hacking, P.; Bally, J.; Black, J.

1986-01-01

Data produced by the Infrared Astronomy Satellite (IRAS) was surveyed at the mid- and far-infrared wavelengths. Visually-identified carbon stars in the 12/25/60 micron color-color diagram were plotted, along with the location of a number of mass-losing stars that lie near the location of the carbon stars, but are not carbon rich. The final sample consisted of 619 objects, which were estimated to be contaminated by 7 % noncarbon-rich objects. The mass return rate was estimated for all evolved circumstellar envelopes. The IRAS Point Source Catalog (PSC) was also searched for the entire class of stars with excess emission. Mass-loss rates, lifetimes, and birthrates for evolved stars were also estimated.

Energy Education: The Quantitative Voice

NASA Astrophysics Data System (ADS)

Wolfson, Richard

2010-02-01

A serious study of energy use and its consequences has to be quantitative. It makes little sense to push your favorite renewable energy source if it can't provide enough energy to make a dent in humankind's prodigious energy consumption. Conversely, it makes no sense to dismiss alternatives---solar in particular---that supply Earth with energy at some 10,000 times our human energy consumption rate. But being quantitative---especially with nonscience students or the general public---is a delicate business. This talk draws on the speaker's experience presenting energy issues to diverse audiences through single lectures, entire courses, and a textbook. The emphasis is on developing a quick, ``back-of-the-envelope'' approach to quantitative understanding of energy issues. )

Statistical analysis of general aviation VG-VGH data

NASA Technical Reports Server (NTRS)

Clay, L. E.; Dickey, R. L.; Moran, M. S.; Payauys, K. W.; Severyn, T. P.

1974-01-01

To represent the loads spectra of general aviation aircraft operating in the Continental United States, VG and VGH data collected since 1963 in eight operational categories were processed and analyzed. Adequacy of data sample and current operational categories, and parameter distributions required for valid data extrapolation were studied along with envelopes of equal probability of exceeding the normal load factor (n sub z) versus airspeed for gust and maneuver loads and the probability of exceeding current design maneuver, gust, and landing impact n sub z limits. The significant findings are included.

Complex analysis of energy efficiency in operated high-rise residential building: Case study

NASA Astrophysics Data System (ADS)

Korniyenko, Sergey

2018-03-01

Energy conservation and human thermal comfort enhancement in buildings is a topical issue of modern architecture and construction. The innovative solution of this problem makes it possible to enhance building ecological and maintenance safety, to reduce hydrocarbon fuel consumption, and to improve life standard of people. The requirements to increase of energy efficiency in buildings should be provided at all the stages of building's life cycle that is at the stage of design, construction and maintenance of buildings. The research purpose is complex analysis of energy efficiency in operated high-rise residential building. Many actions for building energy efficiency are realized according to the project; mainly it is the effective building envelope and engineering systems. Based on results of measurements the energy indicators of the building during annual period have been calculated. The main reason of increase in heat losses consists in the raised infiltration of external air in the building through a building envelope owing to the increased air permeability of windows and balcony doors (construction defects). Thermorenovation of the building based on ventilating and infiltration heat losses reduction through a building envelope allows reducing annual energy consumption. Energy efficiency assessment based on the total annual energy consumption of building, including energy indices for heating and a ventilation, hot water supply and electricity supply, in comparison with heating is more complete. The account of various components in building energy balance completely corresponds to modern direction of researches on energy conservation and thermal comfort enhancement in buildings.

An analog RF gap voltage regulation system for the Advanced Photon Source storage ring.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Horan, D.

1999-04-13

An analog rf gap voltage regulation system has been designed and built at Argonne National Laboratory to maintain constant total storage ring rf gap voltage, independent of beam loading and cavity tuning effects. The design uses feedback control of the klystron mod-anode voltage to vary the amount of rf power fed to the storage ring cavities. The system consists of two independent feedback loops, each regulating the combined rf gap voltages of eight storage ring cavities by varying the output power of either one or two rf stations, depending on the mode of operation. It provides full operator control andmore » permissive logic to permit feedback control of the rf system output power only if proper conditions are met. The feedback system uses envelope-detected cavity field probe outputs as the feedback signal. Two different methods of combining the individual field probe signals were used to generate a relative DC level representing one-half of the total storage ring rf voltage, an envelope-detected vector sum of the field probe rf signals, and the DC sum of individual field probe envelope detector outputs. The merits of both methods are discussed. The klystron high-voltage power supply (HVPS) units are fitted with an analog interface for external control of the mod-anode voltage level, using a four-quadrant analog multiplier to modulate the HVPS mod-anode voltage regulator set-point in response to feedback system commands.« less

Minimal unitary representation of 5d superconformal algebra F(4) and AdS 6/CFT 5 higher spin (super)-algebras

DOE PAGES

Fernando, Sudarshan; Günaydin, Murat

2014-11-28

We study the minimal unitary representation (minrep) of SO(5, 2), obtained by quantization of its geometric quasiconformal action, its deformations and supersymmetric extensions. The minrep of SO(5, 2) describes a massless conformal scalar field in five dimensions and admits a unique “deformation” which describes a massless conformal spinor. Scalar and spinor minreps of SO(5, 2) are the 5d analogs of Dirac’s singletons of SO(3, 2). We then construct the minimal unitary representation of the unique 5d supercon-formal algebra F(4) with the even subalgebra SO(5, 2) ×SU(2). The minrep of F(4) describes a massless conformal supermultiplet consisting of two scalar andmore » one spinor fields. We then extend our results to the construction of higher spin AdS 6/CFT 5 (super)-algebras. The Joseph ideal of the minrep of SO(5, 2) vanishes identically as operators and hence its enveloping algebra yields the AdS 6/CFT 5 bosonic higher spin algebra directly. The enveloping algebra of the spinor minrep defines a “deformed” higher spin algebra for which a deformed Joseph ideal vanishes identically as operators. These results are then extended to the construction of the unique higher spin AdS 6/CFT 5 superalgebra as the enveloping algebra of the minimal unitary realization of F(4) obtained by the quasiconformal methods.« less

Hierarchical Fragmentation in the Perseus Molecular Cloud: From the Cloud Scale to Protostellar Objects

NASA Astrophysics Data System (ADS)

Pokhrel, Riwaj; Myers, Philip C.; Dunham, Michael M.; Stephens, Ian W.; Sadavoy, Sarah I.; Zhang, Qizhou; Bourke, Tyler L.; Tobin, John J.; Lee, Katherine I.; Gutermuth, Robert A.; Offner, Stella S. R.

2018-01-01

We present a study of hierarchical structure in the Perseus molecular cloud, from the scale of the entire cloud (≳ 10 pc) to smaller clumps (∼1 pc), cores (∼0.05–0.1 pc), envelopes (∼300–3000 au), and protostellar objects (∼15 au). We use new observations from the Submillimeter Array (SMA) large project “Mass Assembly of Stellar Systems and their Evolution with the SMA (MASSES)” to probe the envelopes, and recent single-dish and interferometric observations from the literature for the remaining scales. This is the first study to analyze hierarchical structure over five scales in the same cloud complex. We compare the number of fragments with the number of Jeans masses in each scale to calculate the Jeans efficiency, or the ratio of observed to expected number of fragments. The velocity dispersion is assumed to arise either from purely thermal motions or from combined thermal and non-thermal motions inferred from observed spectral line widths. For each scale, thermal Jeans fragmentation predicts more fragments than observed, corresponding to inefficient thermal Jeans fragmentation. For the smallest scale, thermal plus non-thermal Jeans fragmentation also predicts too many protostellar objects. However, at each of the larger scales thermal plus non-thermal Jeans fragmentation predicts fewer than one fragment, corresponding to no fragmentation into envelopes, cores, and clumps. Over all scales, the results are inconsistent with complete Jeans fragmentation based on either thermal or thermal plus non-thermal motions. They are more nearly consistent with inefficient thermal Jeans fragmentation, where the thermal Jeans efficiency increases from the largest to the smallest scale.

Nano-decoration of the Hemagglutinating Virus of Japan envelope (HVJ-E) using a layer-by-layer assembly technique.

PubMed

Okada, Takaharu; Uto, Koichiro; Sasai, Masao; Lee, Chun Man; Ebara, Mitsuhiro; Aoyagi, Takao

2013-06-18

In this study, we created a nanoscale layer of hyaluronic acid (HA) on the inactivated Hemagglutinating Virus of Japan envelope (HVJ-E) via a layer-by-layer (LbL) assembly technique for CD-44 targeted delivery. HVJ-E was selected as the template virus because it has shown a tumor-suppressing ability by eliciting inflammatory cytokine production in dendritic cells. Although it has been required to increase the tumor-targeting ability and reduce nonspecific binding because HVJ-E fuses with virtually all cells and induces hemagglutination in the bloodstream, complete modifications of single-envelope-type viruses with HA have been difficult. Therefore, we studied the surface ζ potential of HVJ-E at different pH values and carefully examined the deposition conditions for the first layer using three cationic polymers: poly-L-lysine (PLL), chitosan (CH), and glycol chitosan (GC). GC-coated HVJ-E particles showed the highest disperse ability under physiological pH and salt conditions without aggregation. An HA layer was then prepared via alternating deposition of HA and GC. The successive decoration of multilayers on HVJ-E has been confirmed by dynamic light scattering (DLS), ζ potentials, and transmission electron microscopy (TEM). An enzymatic degradation assay revealed that only the outermost HA layer was selectively degraded by hyaluronidase. However, entire layers were destabilized at lower pH. Therefore, the HA/GC-coated HVJ-E describe here can be thought of as a potential bomb for cancer immunotherapy because of the ability of targeting CD44 as well as the explosion of nanodecorated HA/GC layers at endosomal pH while preventing nonspecific binding at physiological pH and salt conditions such as in the bloodstream or normal tissues.

SOFIA: Flying the Telescope

NASA Technical Reports Server (NTRS)

Asher, Troy A.; Cumming, Stephen B.

2012-01-01

The primary focus of this paper is how the flight test team for the Stratospheric Observatory For Infrared Astronomy (SOFIA) re-cast an extensive developmental test program to meet key milestones while simultaneously ensuring safe certification of the airframe and delivery of an operationally relevant platform, ultimately saving the overall program from financial demise. Following a brief introduction to the observatory and what it is designed to do, SOFIAs planned developmental test program is summarized, including analysis and design philosophy, envelope expansion, model validation and airframe certification. How NASA used lessons learned from other aircraft that employed open cavities in flight is explained as well as how and why the chosen design was selected. The approach to aerodynamic analysis, including bare airframe testing, wind tunnel testing, computational fluid dynamics and finite element modeling proved absolutely critical. Despite a solid analytical foundation, many unknowns remained. History provides several examples of disastrous effects on both systems and flight safety if cavity design is not approached properly. For these reasons, an extensive test plan was developed to ensure a safe and thorough build-up for envelope expansion, airframe certification and early science missions. Unfortunately, as is often the case, because of chronic delays in overall program execution, severe schedule and funding pressures were present. If critical milestones were not met, domestic as well as international funding was in serious jeopardy, and the demise of the entire program loomed large. Concentrating on rigorous model validation, the test team challenged certification requirements, increased test efficiency and streamlined engineering analysis. This resulted in the safe reduction of test point count by 72%, meeting all program milestones and a platform that soundly satisfied all operational science requirements. Results from early science missions are shown and a proof of concept mission for which SOFIA was opportunely positioned is showcased. Success on this time-critical mission to observe a rare astronomical event proved the usefulness of an airborne observatory and the value in waiting for the capability provided by SOFIA. Finally, lessons learned in the test program are presented with emphasis on how lessons from previous aircraft and successful test programs were applied to SOFIA. Effective application of these lessons was crucial to the success of the SOFIA flight test program. SOFIA is an international cooperative program between NASA and the German Space Agency, DLR. It is a 2.5 meter (100-inch) telescope mounted in a Boeing 747SP aircraft used for astronomical observations at altitudes above 35,000 feet. SOFIA will accommodate a host of scientific instruments from the international science community and has a planned operational lifespan of more than 20 years.

WASTE TREATMENT PLANT (WTP) LIQUID EFFLUENT TREATABILITY EVALUATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

LUECK, K.J.

2004-10-18

A forecast of the radioactive, dangerous liquid effluents expected to be produced by the Waste Treatment Plant (WTP) was provided by Bechtel National, Inc. (BNI 2004). The forecast represents the liquid effluents generated from the processing of Tank Farm waste through the end-of-mission for the WTP. The WTP forecast is provided in the Appendices. The WTP liquid effluents will be stored, treated, and disposed of in the Liquid Effluent Retention Facility (LERF) and the Effluent Treatment Facility (ETF). Both facilities are located in the 200 East Area and are operated by Fluor Hanford, Inc. (FH) for the US. Department ofmore » Energy (DOE). The treatability of the WTP liquid effluents in the LERF/ETF was evaluated. The evaluation was conducted by comparing the forecast to the LERF/ETF treatability envelope (Aromi 1997), which provides information on the items which determine if a liquid effluent is acceptable for receipt and treatment at the LERF/ETF. The format of the evaluation corresponds directly to the outline of the treatability envelope document. Except where noted, the maximum annual average concentrations over the range of the 27 year forecast was evaluated against the treatability envelope. This is an acceptable approach because the volume capacity in the LERF Basin will equalize the minimum and maximum peaks. Background information on the LERF/ETF design basis is provided in the treatability envelope document.« less

Big data, big knowledge: big data for personalized healthcare.

PubMed

Viceconti, Marco; Hunter, Peter; Hose, Rod

2015-07-01

The idea that the purely phenomenological knowledge that we can extract by analyzing large amounts of data can be useful in healthcare seems to contradict the desire of VPH researchers to build detailed mechanistic models for individual patients. But in practice no model is ever entirely phenomenological or entirely mechanistic. We propose in this position paper that big data analytics can be successfully combined with VPH technologies to produce robust and effective in silico medicine solutions. In order to do this, big data technologies must be further developed to cope with some specific requirements that emerge from this application. Such requirements are: working with sensitive data; analytics of complex and heterogeneous data spaces, including nontextual information; distributed data management under security and performance constraints; specialized analytics to integrate bioinformatics and systems biology information with clinical observations at tissue, organ and organisms scales; and specialized analytics to define the "physiological envelope" during the daily life of each patient. These domain-specific requirements suggest a need for targeted funding, in which big data technologies for in silico medicine becomes the research priority.

76 FR 37309 - Parts and Accessories Necessary for Safe Operation; Application for Exemption From the Natural...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-27

... self-addressed, stamped envelope or postcard or print the acknowledgement page that appears after... vehicle fuel systems using compressed natural gas, and applies to passenger cars, multipurpose passenger... vehicle fuel containers, and applies to each passenger car, multipurpose passenger vehicle, truck, and bus...

Operating envelopes of particle sizing instrumentation used for icing research

NASA Technical Reports Server (NTRS)

Hovenac, Edward A.

1987-01-01

The Forward Scattering Spectrometer Probe and the Optical Array Probe are analyzed in terms of their ability to make accurate determinations of water droplet size distributions. Sources of counting and sizing errors are explained. The paper describes ways of identifying these errors and how they can affect measurement.

21 CFR 1040.30 - High-intensity mercury vapor discharge lamps.

Code of Federal Regulations, 2010 CFR

2010-04-01

... vapor lamp, incorporating a high-pressure arc discharge tube that has a fill consisting primarily of... use. (4) Outer envelope means the lamp element, usually glass, surrounding a high-pressure arc... operating time means the sum of the times during which electric current passes through the high-pressure arc...

77 FR 35897 - Drawbridge Operation Regulation; Lafourche Bayou, LA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-15

... additional comments concerning its Notice of Proposed Rulemaking to change the regulation governing the six.... All comments received will be posted, without change to http://www.regulations.gov and will include... envelope. We will consider all comments and material received during the comment period and may change the...

77 FR 539 - Qualification of Drivers; Exemption Applications; Vision

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-05

..., please include a self-addressed, stamped envelope or postcard or print the acknowledgment page that..., Rene Amaya has sufficient vision to perform the driving tasks required to operate a commercial vehicle.'' Mr. Amaya reported that he has driven straight trucks for 2 years, accumulating 78,000 miles and...

Jet Engines as High-Capacity Vacuum Pumps

NASA Technical Reports Server (NTRS)

Wojciechowski, C. J.

1983-01-01

Large diffuser operations envelope and long run times possible. Jet engine driven ejector/diffuser system combines two turbojet engines and variable-area-ratio ejector in two stages. Applications in such industrial proesses as handling corrosive fumes, evaporation of milk and fruit juices, petroleum distillation, and dehydration of blood plasma and penicillin.

Comparative study of air-conditioning energy use of four office buildings in China and USA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Xin; Yan, Da; An, Jingjing

Energy use in buildings has great variability. In order to design and operate low energy buildings as well as to establish building energy codes and standards and effective energy policy, it is crucial to understand and quantify key factors influencing building energy performance. Here, this study investigates air-conditioning (AC) energy use of four office buildings in four locations: Beijing, Taiwan, Hong Kong, and Berkeley. Building simulation was employed to quantify the influences of key factors, including climate, building envelope and occupant behavior. Through simulation of various combinations of the three influencing elements, it is found that climate can lead tomore » AC cooling consumption differences by almost two times, while occupant behavior resulted in the greatest differences (of up to three times) in AC cooling consumption. The influence of occupant behavior on AC energy consumption is not homogeneous. Under similar climates, when the occupant behavior in the building differed, the optimized building envelope design also differed. In conclusion, the optimal building envelope should be determined according to the climate as well as the occupants who use the building.« less

Comparative study of air-conditioning energy use of four office buildings in China and USA

DOE PAGES

Zhou, Xin; Yan, Da; An, Jingjing; ...

2018-04-05

Energy use in buildings has great variability. In order to design and operate low energy buildings as well as to establish building energy codes and standards and effective energy policy, it is crucial to understand and quantify key factors influencing building energy performance. Here, this study investigates air-conditioning (AC) energy use of four office buildings in four locations: Beijing, Taiwan, Hong Kong, and Berkeley. Building simulation was employed to quantify the influences of key factors, including climate, building envelope and occupant behavior. Through simulation of various combinations of the three influencing elements, it is found that climate can lead tomore » AC cooling consumption differences by almost two times, while occupant behavior resulted in the greatest differences (of up to three times) in AC cooling consumption. The influence of occupant behavior on AC energy consumption is not homogeneous. Under similar climates, when the occupant behavior in the building differed, the optimized building envelope design also differed. In conclusion, the optimal building envelope should be determined according to the climate as well as the occupants who use the building.« less

Structural response and gas dynamics of an airship exposed to a nuclear detonation. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gilstad, D.A.; Weeber, C.G.; Kviljord, A.

1960-04-25

Four Model ZSG-3 airships, U. S. Navy Bureau of Aeronautics Nos. 40, 46, 77, and 92, participated during Operation Plumbbob to determine the response characteristics of the Model ZSG-3 airship when subjected to a nuclear detonation in order to establish criteria for safe escape distances for airship delivery of antisubmarine warfare special weapons. Restrained response data for 0.40-psi overpressure input were obtained during Shot Franklin with the ZSG-3 No. 77 moored tail to the blast. Unrestrained response data for 0.75-psi overpressure input were obtained during Shot Stokes with the ZSG-3 No. 40 free ballooned, tail to the blast, 300 feetmore » aboveground. The first airship exposed to overpressure experienced a structural failure of the nose cone when it was rammed into the mooring mast, together with a tear of the forward ballonet which necessitated deflation of the envelope. The second airship broke in half and crashed following a circumferential failure of the envelope originating at the bottom of the envelope, forward of the car.« less

Sentinel-3 for Science

NASA Astrophysics Data System (ADS)

Benveniste, J.; Regner, P.; Desnos, Y. L.

2015-12-01

The Scientific Exploitation of Operational Mission (SEOM) programme element (http://seom.esa.int/) is part of the ESA's Fourth Earth Observation Envelope Programme (2013-2017). The prime objective is to federate, support and expand the international research community that the ERS, ENVISAT and the Envelope programmes have built up over the last 25 years. It aims to further strengthen the leadership of the European Earth Observation research community by enabling them to extensively exploit future European operational EO missions. SEOM is enabling the science community to address new scientific research that are opened by free and open access to data from operational EO missions. The Programme is based on community-wide recommendations for actions on key research issues, gathered through a series of international thematic workshops and scientific user consultation meetings such as the Sentinel-3 for Science Workshop held last June in Venice, Italy (see http://seom.esa.int/S3forScience2015). The 2015 SEOM work plan includes the launch of new R&D studies for scientific exploitation of the Sentinels, the development of open-source multi-mission scientific toolboxes, the organization of advanced international training courses, summer schools and educational materials, as well as activities for promoting the scientific use of EO data, also via the organization of Workshops. This paper will report the recommendations from the International Scientific Community concerning the Sentinel-3 Scientific Exploitation, as expressed in Venice, keeping in mind that Sentinel-3 is an operational mission to provide operational services (see http://www.copernicus.eu).

Environmental performance evaluation of large-scale municipal solid waste incinerators using data envelopment analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, H.-W.; Chang, N.-B., E-mail: nchang@mail.ucf.ed; Chen, J.-C.

2010-07-15

Limited to insufficient land resources, incinerators are considered in many countries such as Japan and Germany as the major technology for a waste management scheme capable of dealing with the increasing demand for municipal and industrial solid waste treatment in urban regions. The evaluation of these municipal incinerators in terms of secondary pollution potential, cost-effectiveness, and operational efficiency has become a new focus in the highly interdisciplinary area of production economics, systems analysis, and waste management. This paper aims to demonstrate the application of data envelopment analysis (DEA) - a production economics tool - to evaluate performance-based efficiencies of 19more » large-scale municipal incinerators in Taiwan with different operational conditions. A 4-year operational data set from 2002 to 2005 was collected in support of DEA modeling using Monte Carlo simulation to outline the possibility distributions of operational efficiency of these incinerators. Uncertainty analysis using the Monte Carlo simulation provides a balance between simplifications of our analysis and the soundness of capturing the essential random features that complicate solid waste management systems. To cope with future challenges, efforts in the DEA modeling, systems analysis, and prediction of the performance of large-scale municipal solid waste incinerators under normal operation and special conditions were directed toward generating a compromised assessment procedure. Our research findings will eventually lead to the identification of the optimal management strategies for promoting the quality of solid waste incineration, not only in Taiwan, but also elsewhere in the world.« less

Features of a Self-Mixing Laser Diode Operating Near Relaxation Oscillation.

PubMed

Liu, Bin; Yu, Yanguang; Xi, Jiangtao; Fan, Yuanlong; Guo, Qinghua; Tong, Jun; Lewis, Roger A

2016-09-21

When a fraction of the light reflected by an external cavity re-enters the laser cavity, both the amplitude and the frequency of the lasing field can be modulated. This phenomenon is called the self-mixing effect (SME). A self-mixing laser diode (SM-LD) is a sensor using the SME. Usually, such LDs operate below the stability boundary where no relaxation oscillation happens. The boundary is determined by the operation condition including the injection current, optical feedback strength and external cavity length. This paper discovers the features of an SM-LD where the LD operates beyond the stability boundary, that is, near the relaxation oscillation (RO) status. We call the signals from such a SM-LD as RO-SM signals to differentiate them from the conventional SM signals reported in the literature. Firstly, simulations are made based on the well-known Lang and Kobayashi (L-K) equations. Then the experiments are conducted on different LDs to verify the simulation results. It shows that a RO-SM signal exhibits high frequency oscillation with its amplitude modulated by a slow time varying envelop which corresponds to the movement of the external target. The envelope has same fringe structure (half-wavelength displacement resolution) with the conventional SM signals. However, the amplitudes of the RO-SM signals are much higher compared to conventional SM signals. The results presented reveal that an SM-LD operating near the RO has potential for achieving sensing with improved sensitivity.

Features of a Self-Mixing Laser Diode Operating Near Relaxation Oscillation

PubMed Central

Liu, Bin; Yu, Yanguang; Xi, Jiangtao; Fan, Yuanlong; Guo, Qinghua; Tong, Jun; Lewis, Roger A.

2016-01-01

When a fraction of the light reflected by an external cavity re-enters the laser cavity, both the amplitude and the frequency of the lasing field can be modulated. This phenomenon is called the self-mixing effect (SME). A self-mixing laser diode (SM-LD) is a sensor using the SME. Usually, such LDs operate below the stability boundary where no relaxation oscillation happens. The boundary is determined by the operation condition including the injection current, optical feedback strength and external cavity length. This paper discovers the features of an SM-LD where the LD operates beyond the stability boundary, that is, near the relaxation oscillation (RO) status. We call the signals from such a SM-LD as RO-SM signals to differentiate them from the conventional SM signals reported in the literature. Firstly, simulations are made based on the well-known Lang and Kobayashi (L-K) equations. Then the experiments are conducted on different LDs to verify the simulation results. It shows that a RO-SM signal exhibits high frequency oscillation with its amplitude modulated by a slow time varying envelop which corresponds to the movement of the external target. The envelope has same fringe structure (half-wavelength displacement resolution) with the conventional SM signals. However, the amplitudes of the RO-SM signals are much higher compared to conventional SM signals. The results presented reveal that an SM-LD operating near the RO has potential for achieving sensing with improved sensitivity. PMID:27657077

Conservation of proteo-lipid nuclear membrane fusion machinery during early embryogenesis.

PubMed

Byrne, Richard D; Veeriah, Selvaraju; Applebee, Christopher J; Larijani, Banafshé

2014-01-01

The fusogenic lipid diacylglycerol is essential for remodeling gamete and zygote nuclear envelopes (NE) during early embryogenesis. It is unclear whether upstream signaling molecules are likewise conserved. Here we demonstrate PLCγ and its activator SFK1, which co-operate during male pronuclear envelope formation, also promote the subsequent male and female pronuclear fusion. PLCγ and SFK1 interact directly at the fusion site leading to PLCγ activation. This is accompanied by a spatially restricted reduction of PtdIns(4,5)P2. Consequently, pronuclear fusion is blocked by PLCγ or SFK1 inhibition. These findings identify new regulators of events in the early embryo and suggest a conserved "toolkit" of fusion machinery drives successive NE fusion events during embryogenesis.

IUE observations of symbiotic stars

NASA Technical Reports Server (NTRS)

Hack, M.

1982-01-01

The main photometric and spectroscopic characteristics in the ultraviolet and visual range of the most extensively studied symbiotic stars are reviewed. The main data obtained with IUE concern: (1) the determination of the shape of the UV continuum, which, in some cases, proves without doubt the presence of a hot companion; and the determination of the interstellar extinction by means of the lambda 2200 feature; (2) the measurement of emission lines, which enables us to derive the electron temperature and density of the circumstellar envelope, and, taken together with those lines observed in the visual, give more complete information on which spectroscopic mechanisms operate in the envelope; (3) the observation of absorption lines in the UV, which are present in just a few cases.

Carrier-envelope frequency stabilization of a Ti:sapphire oscillator using different pump lasers.

PubMed

Vernaleken, Andreas; Schmidt, Bernhard; Wolferstetter, Martin; Hänsch, Theodor W; Holzwarth, Ronald; Hommelhoff, Peter

2012-07-30

We investigate the suitability of various commercially available pump lasers for operation with a carrier-envelope offset frequency stabilized Ti:sapphire oscillator. Although the tested pump lasers differ in their setup and properties (e.g., single vs. multi-mode), we find that they are all well-suited for the purpose. The residual rms phase noise (integrated between 20 Hz and 5 MHz) of the stabilized oscillator is found to be below 160 mrad with each pump laser, corresponding to less than 1/40 of an optical cycle. Differences in performance vary slightly. In particular, our results indicate that the latest generation of multi-mode pump lasers can be used for applications where precise phase control of the oscillator is strictly required.

Corrosion in MDEA sour gas treating plants: Correlation between laboratory testing and field experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bich, N.N.; Vacha, F.; Schubert, R.

1996-08-01

Corrosion in MDEA sour gas treating systems operating in severely loaded conditions is investigated using both laboratory data and actual gas plant experience. Effects of acid gas loading, flow turbulence, solution quality, temperature, etc. on corrosion are being studied. Preliminary results indicated severe corrosion of several mm/y would occur if acid gas loading, circulation rate and level of suspended solids are all high. A mitigation strategy based on operating envelopes is formulated.

Operation of the intensity monitors in beam transport lines at Fermilab during Run II¹

DOE PAGES

Crisp, J.; Fellenz, B.; Fitzgerald, J.; ...

2011-10-06

The intensity of charged particle beams at Fermilab must be kept within pre-determined safety and operational envelopes in part by assuring all beam within a few percent has been transported from any source to destination. Beam instensity monitors with toroidial pickups provide such beam intensity measurements in the transport lines between accelerators at FNAL. With Run II, much effort was made to continually improve the resolution and accuracy of the system.

Sea level static calibration of a compact multimission aircraft propulsion simulator with inlet flow distortion

NASA Technical Reports Server (NTRS)

Won, Mark J.

1990-01-01

Wind tunnel tests of propulsion-integrated aircraft models have identified inlet flow distortion as a major source of compressor airflow measurement error in turbine-powered propulsion simulators. Consequently, two Compact Multimission Aircraft Propulsion Simulator (CMAPS) units were statically tested at sea level ambient conditions to establish simulator operating performance characteristics and to calibrate the compressor airflow against an accurate bellmouth flowmeter in the presence of inlet flow distortions. The distortions were generated using various-shaped wire mesh screens placed upstream of the compressor. CMAPS operating maps and performance envelopes were obtained for inlet total pressure distortions (ratio of the difference between the maximum and minimum total pressures to the average total pressure) up to 35 percent, and were compared to baseline simulator operating characteristics for a uniform inlet. Deviations from CMAPS baseline performance were attributed to the coupled variation of both compressor inlet-flow distortion and Reynolds number index throughout the simulator operating envelope for each screen configuration. Four independent methods were used to determine CMAPS compressor airflow; direct compressor inlet and discharge measurements, an entering/exiting flow-balance relationships, and a correlation between the mixer pressure and the corrected compressor airflow. Of the four methods, the last yielded the least scatter in the compressor flow coefficient, approximately + or - 3 percent over the range of flow distortions.

Vaginal challenge with an SIV-based dual reporter system reveals that infection can occur throughout the upper and lower female reproductive tract.

PubMed

Stieh, Daniel J; Maric, Danijela; Kelley, Z L; Anderson, Meegan R; Hattaway, Holly Z; Beilfuss, Beth A; Rothwangl, Katharina B; Veazey, Ronald S; Hope, Thomas J

2014-10-01

The majority of new HIV infections occur in women as a result of heterosexual intercourse, overcoming multiple innate barriers to infection within the mucosa. However, the avenues through which infection is established, and the nature of bottlenecks to transmission, have been the source of considerable investigation and contention. Using a high dose of a single round non-replicating SIV-based vector containing a novel dual reporter system, we determined the sites of infection by the inoculum using the rhesus macaque vaginal transmission model. Here we show that the entire female reproductive tract (FRT), including the vagina, ecto- and endocervix, along with ovaries and local draining lymph nodes can contain transduced cells only 48 hours after inoculation. The distribution of infection shows that virions quickly disseminate after exposure and can access target cells throughout the FRT, with an apparent preference for infection in squamous vaginal and ectocervical mucosa. JRFL enveloped virions infect diverse CD4 expressing cell types, with T cells resident throughout the FRT representing the primary target. These findings establish a new perspective that the entire FRT is susceptible and virus can reach as far as the ovary and local draining lymph nodes. Based on these findings, it is essential that protective mechanisms for prevention of HIV acquisition must be present at protective levels throughout the entire FRT to provide complete protection.

A methodology for the efficient integration of transient constraints in the design of aircraft dynamic systems

NASA Astrophysics Data System (ADS)

Phan, Leon L.

The motivation behind this thesis mainly stems from previous work performed at Hispano-Suiza (Safran Group) in the context of the European research project "Power Optimised Aircraft". Extensive testing on the COPPER Bird RTM, a test rig designed to characterize aircraft electrical networks, demonstrated the relevance of transient regimes in the design and development of dynamic systems. Transient regimes experienced by dynamic systems may have severe impacts on the operation of the aircraft. For example, the switching on of a high electrical load might cause a network voltage drop inducing a loss of power available to critical aircraft systems. These transient behaviors are thus often regulated by dynamic constraints, requiring the dynamic signals to remain within bounds whose values vary with time. The verification of these peculiar types of constraints, which generally requires high-fidelity time-domain simulation, intervenes late in the system development process, thus potentially causing costly design iterations. The research objective of this thesis is to develop a methodology that integrates the verification of dynamic constraints in the early specification of dynamic systems. In order to circumvent the inefficiencies of time-domain simulation, multivariate dynamic surrogate models of the original time-domain simulation models are generated, building on a nonlinear system identification technique using wavelet neural networks (or wavenets), which allow the multiscale nature of transient signals to be captured. However, training multivariate wavenets can become computationally prohibitive as the number of design variables increases. Therefore, an alternate approach is formulated, in which dynamic surrogate models using sigmoid-based neural networks are used to emulate the transient behavior of the envelopes of the time-domain response. Thus, in order to train the neural network, the envelopes are extracted by first separating the scales of the dynamic response, using a multiresolution analysis (MRA) based on the discrete wavelet transform. The MRA separates the dynamic response into a trend and a noise signal (ripple). The envelope of the noise is then computed with a windowing method, and recombined with the trend in order to reconstruct the global envelope of the dynamic response. The run-time efficiency of the resulting dynamic surrogate models enable the implementation of a data farming approach, in which a Monte-Carlo simulation generates time-domain behaviors of transient responses for a vast set of design and operation scenarios spanning the design and operation space. An interactive visualization environment, enabling what-if analyses, will be developed; the user can thereby instantaneously comprehend the transient response of the system (or its envelope) and its sensitivities to design and operation variables, as well as filter the design space to have it exhibit only the design scenarios verifying the dynamic constraints. The proposed methodology, along with its foundational hypotheses, are tested on the design and optimization of a 350VDC network, where a generator and its control system are concurrently designed in order to minimize the electrical losses, while ensuring that the transient undervoltage induced by peak demands in the consumption of a motor does not violate transient power quality constraints.

Properties of Ferrite Garnet (Bi, Lu, Y)3(Fe, Ga)5O12 Thin Film Materials Prepared by RF Magnetron Sputtering

PubMed Central

Nur-E-Alam, Mohammad; Belotelov, Vladimir; Alameh, Kamal

2018-01-01

This work is devoted to physical vapor deposition synthesis, and characterisation of bismuth and lutetium-substituted ferrite-garnet thin-film materials for magneto-optic (MO) applications. The properties of garnet thin films sputtered using a target of nominal composition type Bi0.9Lu1.85Y0.25Fe4.0Ga1O12 are studied. By measuring the optical transmission spectra at room temperature, the optical constants and the accurate film thicknesses can be evaluated using Swanepoel’s envelope method. The refractive index data are found to be matching very closely to these derived from Cauchy’s dispersion formula for the entire spectral range between 300 and 2500 nm. The optical absorption coefficient and the extinction coefficient data are studied for both the as-deposited and annealed garnet thin-film samples. A new approach is applied to accurately derive the optical constants data simultaneously with the physical layer thickness, using a combination approach employing custom-built spectrum-fitting software in conjunction with Swanepoel’s envelope method. MO properties, such as specific Faraday rotation, MO figure of merit and MO swing factor are also investigated for several annealed garnet-phase films. PMID:29789463

Pabon Lasso and Data Envelopment Analysis: A Complementary Approach to Hospital Performance Measurement

PubMed Central

Mehrtak, Mohammad; Yusefzadeh, Hasan; Jaafaripooyan, Ebrahim

2014-01-01

Background: Performance measurement is essential to the management of health care organizations to which efficiency is per se a vital indicator. Present study accordingly aims to measure the efficiency of hospitals employing two distinct methods. Methods: Data Envelopment Analysis and Pabon Lasso Model were jointly applied to calculate the efficiency of all general hospitals located in Iranian Eastern Azerbijan Province. Data was collected using hospitals’ monthly performance forms and analyzed and displayed by MS Visio and DEAP software. Results: In accord with Pabon Lasso model, 44.5% of the hospitals were entirely efficient, whilst DEA revealed 61% to be efficient. As such, 39% of the hospitals, by the Pabon Lasso, were wholly inefficient; based on DEA though; the relevant figure was only 22.2%. Finally, 16.5% of hospitals as calculated by Pabon Lasso and 16.7% by DEA were relatively efficient. DEA appeared to show more hospitals as efficient as opposed to the Pabon Lasso model. Conclusion: Simultaneous use of two models rendered complementary and corroborative results as both evidently reveal efficient hospitals. However, their results should be compared with prudence. Whilst the Pabon Lasso inefficient zone is fully clear, DEA does not provide such a crystal clear limit for inefficiency. PMID:24999147

Motion-compensated optical coherence tomography using envelope-based surface detection and Kalman-based prediction

NASA Astrophysics Data System (ADS)

Irsch, Kristina; Lee, Soohyun; Bose, Sanjukta N.; Kang, Jin U.

2018-02-01

We present an optical coherence tomography (OCT) imaging system that effectively compensates unwanted axial motion with micron-scale accuracy. The OCT system is based on a swept-source (SS) engine (1060-nm center wavelength, 100-nm full-width sweeping bandwidth, and 100-kHz repetition rate), with axial and lateral resolutions of about 4.5 and 8.5 microns respectively. The SS-OCT system incorporates a distance sensing method utilizing an envelope-based surface detection algorithm. The algorithm locates the target surface from the B-scans, taking into account not just the first or highest peak but the entire signature of sequential A-scans. Subsequently, a Kalman filter is applied as predictor to make up for system latencies, before sending the calculated position information to control a linear motor, adjusting and maintaining a fixed system-target distance. To test system performance, the motioncorrection algorithm was compared to earlier, more basic peak-based surface detection methods and to performing no motion compensation. Results demonstrate increased robustness and reproducibility, particularly noticeable in multilayered tissues, while utilizing the novel technique. Implementing such motion compensation into clinical OCT systems may thus improve the reliability of objective and quantitative information that can be extracted from OCT measurements.

A physiologically based model for temporal envelope encoding in human primary auditory cortex.

PubMed

Dugué, Pierre; Le Bouquin-Jeannès, Régine; Edeline, Jean-Marc; Faucon, Gérard

2010-09-01

Communication sounds exhibit temporal envelope fluctuations in the low frequency range (<70 Hz) and human speech has prominent 2-16 Hz modulations with a maximum at 3-4 Hz. Here, we propose a new phenomenological model of the human auditory pathway (from cochlea to primary auditory cortex) to simulate responses to amplitude-modulated white noise. To validate the model, performance was estimated by quantifying temporal modulation transfer functions (TMTFs). Previous models considered either the lower stages of the auditory system (up to the inferior colliculus) or only the thalamocortical loop. The present model, divided in two stages, is based on anatomical and physiological findings and includes the entire auditory pathway. The first stage, from the outer ear to the colliculus, incorporates inhibitory interneurons in the cochlear nucleus to increase performance at high stimuli levels. The second stage takes into account the anatomical connections of the thalamocortical system and includes the fast and slow excitatory and inhibitory currents. After optimizing the parameters of the model to reproduce the diversity of TMTFs obtained from human subjects, a patient-specific model was derived and the parameters were optimized to effectively reproduce both spontaneous activity and the oscillatory part of the evoked response. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Performance of a Low-Power Cylindrical Hall Thruster

NASA Technical Reports Server (NTRS)

Polzin, Kurt A.; Markusic, Thomas E.; Stanojev, Boris J.; Dehoyos, Amado; Raitses, Yevgeny; Smirnov, Artem; Fisch, Nathaniel J.

2007-01-01

Recent mission studies have shown that a Hall thruster which operates at relatively constant thrust efficiency (45-55%) over a broad power range (300W - 3kW) is enabling for deep space science missions when compared with slate-of-the-art ion thrusters. While conventional (annular) Hall thrusters can operate at high thrust efficiency at kW power levels, it is difficult to construct one that operates over a broad power envelope down to 0 (100 W) while maintaining relatively high efficiency. In this note we report the measured performance (I(sub sp), thrust and efficiency) of a cylindrical Hall thruster operating at 0 (100 W) input power.

Symbiotic nova V1016 Cygni: Evolution of the dust envelope and the gaseous nebula

NASA Astrophysics Data System (ADS)

Arkhipova, V. P.; Taranova, O. G.; Ikonnikova, N. P.; Esipov, V. F.; Komissarova, G. V.; Shenavrin, V. I.

2015-11-01

As a result of the next cycle of our long-term monitoring, we present our UBV JHKLM photometry for the symbiotic nova V1016 Cyg in 2008-2014. The star continued to systematically fade and redden in UBV: over this period, the brightness declined by 0 ṃ1 in V and by 0 ṃ2 in B and U, the B-V color index increased by 0 ṃ1, and U-B barely changed. On the color-color ( U-B, B-V) diagram, the star moved approximately horizontally rightward with a slight bluing in U-B starting from 2000. Our JHKLM photometry has shown a decline in the mean infrared (IR) brightness and a rise in the mean IR color indices after 2004 due to an increase in the optical depth of the dust envelope. The brightness decline and reddening of the Mira in the near infrared reached their extreme values over the entire period of the system's observations by the end of 2014. The pulsation period of the Mira is determined with confidence: P = 465 ± 5 days. The distance to the Mira, D = 2.92 ± 0.16 kpc, and its parameters, the radius R * = (470 ± 50) R ⊙ and luminosity L * = (9200 ± 1900) L ⊙, have been estimated from the observations of V1016 Cyg at its maximum J brightness and at its minimum J-H color index. The temperature of the star during its pulsations varied within the range T * = 2100-2700 K.We have estimated the parameters of the dust envelope near its maximum (in 2004) and minimum (in 2012-2014) IR brightness. The mass of the dust envelope almost doubled in ten years, with the rate of dust supply being Δ M d ˜ 10-7 M ⊙ yr-1. Using a low-resolution spectrograph, we performed absolute spectrophotometry for V1016 Cyg in 1995-2013 in the range λ4340-7130 Å. We have shown that almost all absolute fluxes in lines and in continuum at λ4400 Å decrease monotonically after 2000, while the relative intensities of [O III], [Fe VII], and [Ca VII] lines increase after the minimum that probably occurred in the 1990s. The significant (approximately by a factor of 10 from 1995 to 2013) decrease of the flux in the Raman O VI λ6825 line reflects a change of conditions in the formation zone of this line due to the absorption of some O VI λ1032 photons in the newly forming dust envelope of the cool component.

Bootstrapping data envelopment analysis of efficiency and productivity of county public hospitals in Eastern, Central, and Western China after the public hospital reform.

PubMed

Wang, Man-Li; Fang, Hai-Qing; Tao, Hong-Bing; Cheng, Zhao-Hui; Lin, Xiao-Jun; Cai, Miao; Xu, Chang; Jiang, Shuai

2017-10-01

China implemented the public hospital reform in 2012. This study utilized bootstrapping data envelopment analysis (DEA) to evaluate the technical efficiency (TE) and productivity of county public hospitals in Eastern, Central, and Western China after the 2012 public hospital reform. Data from 127 county public hospitals (39, 45, and 43 in Eastern, Central, and Western China, respectively) were collected during 2012-2015. Changes of TE and productivity over time were estimated by bootstrapping DEA and bootstrapping Malmquist. The disparities in TE and productivity among public hospitals in the three regions of China were compared by Kruskal-Wallis H test and Mann-Whitney U test. The average bias-corrected TE values for the four-year period were 0.6442, 0.5785, 0.6099, and 0.6094 in Eastern, Central, and Western China, and the entire country respectively, with average non-technical efficiency, low pure technical efficiency (PTE), and high scale efficiency found. Productivity increased by 8.12%, 0.25%, 12.11%, and 11.58% in China and its three regions during 2012-2015, and such increase in productivity resulted from progressive technological changes by 16.42%, 6.32%, 21.08%, and 21.42%, respectively. The TE and PTE of the county hospitals significantly differed among the three regions of China. Eastern and Western China showed significantly higher TE and PTE than Central China. More than 60% of county public hospitals in China and its three areas operated at decreasing return scales. There was a considerable space for TE improvement in county hospitals in China and its three regions. During 2012-2015, the hospitals experienced progressive productivity; however, the PTE changed adversely. Moreover, Central China continuously achieved a significantly lower efficiency score than Eastern and Western China. Decision makers and administrators in China should identify the causes of the observed inefficiencies and take appropriate measures to increase the efficiency of county public hospitals in the three areas of China, especially in Central China.

Technologies developed by CNES balloon team

NASA Astrophysics Data System (ADS)

Sosa-Sesma, Sergio; Charbonnier, Jean-Marc; Deramecourt, Arnaud

CNES balloon team develops and operates all the components of this kind of vehicle: it means envelope and gondola. This abstract will point out only developments done for envelope. Nowadays CNES offers to scientists four types of envelops that cover a large range of mission demands. These envelops are: 1. Zero pressure balloons: Size going from 3,000m3 to 600,000m3, this kind of envelop is ideal for short duration flights (a few hours) but if we use an intelligent management of ballast consumption and if we chose the best launch site, it is possible to perform medium duration flights (10/20 days depending on the ballast on board). Flight train mass starts at 50kg for small balloons and reach 1000kg for larger ones. Zero pressure balloons are inflated with helium gas. 2. Super pressure balloons: Diameter going from 2.5m to 12m, this kind of envelop is ideal for long duration flights (1 to 6 months). Flight train is inside the envelop for small balloons, it means 2.5 diameter meters which is usually called BPCL (Super pressure balloon for Earth boundary layer) and it is about 3kg of mass. Larger ones could lift external flight trains about 50kg of mass. Super pressure balloons are inflated with helium gas. 3. MIR balloons: Size going from 36,000m3 to 46,000m3. Ceiling is reach with helium gas but after three days helium is no longer present inside and lift force is produced by difference of temperature between air inside and air of atmosphere. Flight trains must not be over 50kg. 4. Aero Clipper balloons: A concept to correlate measurements done in oceans and in nearest layers of atmosphere simultaneously. Flight train is made by a "fish" that drags inside water and an atmospheric gondola few meters above "fish", both pushed by a balloon which profits of the wind force. Materials used for construction and assembling depend on balloon type; they are usually made of polyester or polyethylene. Thickness varies from 12 micrometers to 120 micrometers. Balloon assembling is made at ZODIAC site (near Toulouse) by Zodiac teams although all mechanical machines belong to CNES. These machines had been developed by CNES to cut, to weld and to thermo-joint the different parts of the balloon.

76 FR 80829 - Special Conditions: XtremeAir GmbH, XA42; Acrobatic Category Aerodynamic Stability

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-27

... at the highest level of aerobatic competition. To be competitive, the aircraft was designed with... envelope to accommodate the increased fuel load designed for cross-country operations. The FAA does recognize that fuel exhaustion is one of the top accident causes associated with this class of aircraft. For...

14 CFR 31.85 - Required basic equipment.

Code of Federal Regulations, 2010 CFR

2010-01-01

... calibrated in appropriate units or in percent of fuel cell capacity. (2) An envelope temperature indicator. (c) For captive gas balloons, a compass. [Amdt. 31-2, 30 FR 3377, Mar. 13, 1965, as amended by Amdt... equipment. In addition to any equipment required by this subchapter for a specific kind of operation, the...

Center for the Built Environment: Research on Building Envelope Systems

Science.gov Websites

Studies Facade and Perimeter Zone Field Study Facades and Thermal Comfort Facade Symposium Mixed-Mode Research Adaptive Comfort Model Mixed-Mode Case Studies Operable Windows and Thermal Comfort Occupant thermal preferences in naturally ventilated as sealed buildings? Case Study Research of Mixed-Mode Office

Addendum to NuMI shielding assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vaziri, Kamran; /Fermilab

2007-10-01

The original safety assessment and the Safety Envelope for the NuMI beam line corresponds to 400 kW of beam power. The Main Injector is currently capable of and approved for producing 500 kW of beam power2. However, operation of the NuMI beam line at 400 kW of power brings up the possibility of an occasional excursion above 400 kW due to better than usual tuning in one of the machines upstream of the NuMI beam line. An excursion above the DOE approved Safety Envelope will constitute a safety violation. The purpose of this addendum is to evaluate the radiological issuesmore » and modifications required to operate the NuMI beam line at 500 kW. This upgrade will allow 400 kW operations with a reasonable safety margin. Configuration of the NuMI beam line, boundaries, safety system and the methodologies used for the calculations are as described in the original NuMI SAD. While most of the calculations presented in the original shielding assessment were based on Monte Carlo simulations, which were based on the design geometries, most of the results presented in this addendum are based on the measurements conducted by the AD ES&H radiation safety group.« less

Characterization of a 50kW Inductively Coupled Plasma Torch for Testing of Ablative Thermal Protection Materials

NASA Technical Reports Server (NTRS)

Greene, Benton R.; Clemens, Noel T.; Varghese, Philip L.; Bouslog, Stanley A.; Del Papa, Steven V.

2017-01-01

With the development of new manned spaceflight capabilities including NASA's Orion capsule and the Space-X Dragon capsule, there is a renewed importance of understanding the dynamics of ablative thermal protection systems. To this end, a new inductively coupled plasma torch facility is being developed at UT-Austin. The torch operates on argon and/or air at plasma powers up to 50 kW. In the present configuration the flow issues from a low-speed subsonic nozzle and the hot plume is characterized using slug calorimetry and emission spectroscopy. Preliminary measurements using emission spectroscopy have indicated that the torch is capable of producing an air plasma with a temperature between 6,000 K and 8,000 K depending on the power and flow settings and an argon plasma with a temperature of approximately 12,000 K. The operation envelope was measured, and heat flux measured for every point within the envelope using both a slug calorimeter and a Gardon gauge heat flux sensor. The torch was found to induce a stagnation point heat flux of between 90 and 225 W/sq cm.

The balloon and the airship technological heritage

NASA Technical Reports Server (NTRS)

Mayer, N. J.

1981-01-01

The balloon and the airship are discussed with emphasis on the identification of commonalities and distinctions. The aerostat technology behind the shape and structure of the vehicles is reviewed, including a discussion of structural weight, internal pressure, buckling, and the development of a stable tethered balloon system. Proper materials for the envelope are considered, taking elongation and stress into account, and flight operation and future developments are reviewed. Airships and tethered balloons which are designed to carry high operating pressure with low gas loss characteristics are found to share similar problems in low speed flight operations, while possessing interchangeable technologies.

Combustion performance and heat transfer characterization of LOX/hydrocarbon type propellants. Task 3: Data dump

NASA Technical Reports Server (NTRS)

Hart, S. W.

1982-01-01

A preliminary characterization of Orbital Maneuvering System (OMS) and Reaction Control System (RCS) engine point designs over a range of thrust and chamber pressure for several hydrocarbon fuels is reported. OMS and RCS engine point designs were established in two phases comprising baseline and parametric designs. Interface pressures, performance and operating parameters, combustion chamber cooling and turboprop requirements, component weights and envelopes, and propellant conditioning requirements for liquid to vapor phase engine operation are defined.

Operational Principles. The Operational Art of Erwin Rommel and Bernard Montgomery

DTIC Science & Technology

1985-01-01

greatly reduced. Flanking and enveloping attacks threaten the enemy, attack , his will , and cause him to pause. The pause creates further opportunity to...undisciplined, inattentive to school- * work , and did not live up to his parents’ expectations. There was no siwnificant military tradition in his family . He...philosophy as follows: You will notice that I use the word "normal" a great deal. I am a great believer in giving people a "normal" to work on. My

High efficiency RF amplifier development over wide dynamic range for accelerator application

NASA Astrophysics Data System (ADS)

Mishra, Jitendra Kumar; Ramarao, B. V.; Pande, Manjiri M.; Joshi, Gopal; Sharma, Archana; Singh, Pitamber

2017-10-01

Superconducting (SC) cavities in an accelerating section are designed to have the same geometrical velocity factor (βg). For these cavities, Radio Frequency (RF) power needed to accelerate charged particles varies with the particle velocity factor (β). RF power requirement from one cavity to other can vary by 2-5 dB within the accelerating section depending on the energy gain in the cavity and beam current. In this paper, we have presented an idea to improve operating efficiency of the SC RF accelerators using envelope tracking technique. A study on envelope tracking technique without feedback is carried out on a 1 kW, 325 MHz, class B (conduction angle of 180 degrees) tuned load power amplifier (PA). We have derived expressions for the efficiency and power output for tuned load amplifier operating on the envelope tracking technique. From the derived expressions, it is observed that under constant load resistance to the device (MOSFET), optimum amplifier efficiency is invariant whereas output power varies with the square of drain bias voltage. Experimental results on 1 kW PA module show that its optimum efficiency is always greater than 62% with variation less than 5% from mean value over 7 dB dynamic range. Low power amplifier modules are the basic building block for the high power amplifiers. Therefore, results for 1 kW PA modules remain valid for the high power solid state amplifiers built using these PA modules. The SC RF accelerators using these constant efficiency power amplifiers can improve overall accelerator efficiency.

Condensins exert force on chromatin-nuclear envelope tethers to mediate nucleoplasmic reticulum formation in Drosophila melanogaster.

PubMed

Bozler, Julianna; Nguyen, Huy Q; Rogers, Gregory C; Bosco, Giovanni

2014-12-30

Although the nuclear envelope is known primarily for its role as a boundary between the nucleus and cytoplasm in eukaryotes, it plays a vital and dynamic role in many cellular processes. Studies of nuclear structure have revealed tissue-specific changes in nuclear envelope architecture, suggesting that its three-dimensional structure contributes to its functionality. Despite the importance of the nuclear envelope, the factors that regulate and maintain nuclear envelope shape remain largely unexplored. The nuclear envelope makes extensive and dynamic interactions with the underlying chromatin. Given this inexorable link between chromatin and the nuclear envelope, it is possible that local and global chromatin organization reciprocally impact nuclear envelope form and function. In this study, we use Drosophila salivary glands to show that the three-dimensional structure of the nuclear envelope can be altered with condensin II-mediated chromatin condensation. Both naturally occurring and engineered chromatin-envelope interactions are sufficient to allow chromatin compaction forces to drive distortions of the nuclear envelope. Weakening of the nuclear lamina further enhanced envelope remodeling, suggesting that envelope structure is capable of counterbalancing chromatin compaction forces. Our experiments reveal that the nucleoplasmic reticulum is born of the nuclear envelope and remains dynamic in that they can be reabsorbed into the nuclear envelope. We propose a model where inner nuclear envelope-chromatin tethers allow interphase chromosome movements to change nuclear envelope morphology. Therefore, interphase chromatin compaction may be a normal mechanism that reorganizes nuclear architecture, while under pathological conditions, such as laminopathies, compaction forces may contribute to defects in nuclear morphology. Copyright © 2015 Bozler et al.

Condensins Exert Force on Chromatin-Nuclear Envelope Tethers to Mediate Nucleoplasmic Reticulum Formation in Drosophila melanogaster

PubMed Central

Bozler, Julianna; Nguyen, Huy Q.; Rogers, Gregory C.; Bosco, Giovanni

2014-01-01

Although the nuclear envelope is known primarily for its role as a boundary between the nucleus and cytoplasm in eukaryotes, it plays a vital and dynamic role in many cellular processes. Studies of nuclear structure have revealed tissue-specific changes in nuclear envelope architecture, suggesting that its three-dimensional structure contributes to its functionality. Despite the importance of the nuclear envelope, the factors that regulate and maintain nuclear envelope shape remain largely unexplored. The nuclear envelope makes extensive and dynamic interactions with the underlying chromatin. Given this inexorable link between chromatin and the nuclear envelope, it is possible that local and global chromatin organization reciprocally impact nuclear envelope form and function. In this study, we use Drosophila salivary glands to show that the three-dimensional structure of the nuclear envelope can be altered with condensin II-mediated chromatin condensation. Both naturally occurring and engineered chromatin-envelope interactions are sufficient to allow chromatin compaction forces to drive distortions of the nuclear envelope. Weakening of the nuclear lamina further enhanced envelope remodeling, suggesting that envelope structure is capable of counterbalancing chromatin compaction forces. Our experiments reveal that the nucleoplasmic reticulum is born of the nuclear envelope and remains dynamic in that they can be reabsorbed into the nuclear envelope. We propose a model where inner nuclear envelope-chromatin tethers allow interphase chromosome movements to change nuclear envelope morphology. Therefore, interphase chromatin compaction may be a normal mechanism that reorganizes nuclear architecture, while under pathological conditions, such as laminopathies, compaction forces may contribute to defects in nuclear morphology. PMID:25552604

Optimum Design of Hypersonic Airbreathing Propulsion

NASA Astrophysics Data System (ADS)

Kobayashi, Hiroaki; Sato, Tetsuya; Tanatsugu, Nobuhiro

The flight of Spaceplane is always under accelarating in the assent way and always under decelarating in the desent way and yet cruising in the return way. Besides, its flight envelope is considerably wider than that of airplane. Thus the integrated design method is required to build the best transportation system optimized taking into account the propulsion system and the airframe under the entire flight conditions. In this paper it is shown an optimization method on TSTO spaceplane system. Genetic algorithm (GA) was applied to optimize design parameters of engine, airframe, and trajectory simultaneously. Several types of engine were quantitatively compared using payload ratio as an evaluating function. It was concluded that precooled turbojets is the most promising engine for TSTO among Turbine Based Combined Cycle (TBCC) engines.

A distinctive type of ascending prominence - 'Fountain'

NASA Technical Reports Server (NTRS)

Tandberg-Hanssen, E.; Hansen, R. T.; Riddle, A. C.

1975-01-01

Cinematographic observations of solar prominences made at Mauna Loa, Hawaii, during the past few years suggest that there is a well-defined subclass of ascending prominences characterized by closed-system transference of chromospheric material along an arch or loop (up one leg and down the other). While this occurs, the entire prominence envelope steadily rises upward and expands through the corona. These prominences are denoted as 'fountains'. Several examples are described. Fountains appear to be well contained by coronal magnetic fields. Their total kinetic energy is of the order of 10 to the 30th power erg, but dissipation is typically quite slow (over time periods of 100 min or so), so that the correlative disturbances (radio bursts, coronal transients, chromospheric brightenings) are generally not spectacular or nonexistent.

Modeling the High Speed Research Cycle 2B Longitudinal Aerodynamic Database Using Multivariate Orthogonal Functions

NASA Technical Reports Server (NTRS)

Morelli, E. A.; Proffitt, M. S.

1999-01-01

The data for longitudinal non-dimensional, aerodynamic coefficients in the High Speed Research Cycle 2B aerodynamic database were modeled using polynomial expressions identified with an orthogonal function modeling technique. The discrepancy between the tabular aerodynamic data and the polynomial models was tested and shown to be less than 15 percent for drag, lift, and pitching moment coefficients over the entire flight envelope. Most of this discrepancy was traced to smoothing local measurement noise and to the omission of mass case 5 data in the modeling process. A simulation check case showed that the polynomial models provided a compact and accurate representation of the nonlinear aerodynamic dependencies contained in the HSR Cycle 2B tabular aerodynamic database.

State-Of High Brightness RF Photo-Injector Design

NASA Astrophysics Data System (ADS)

Ferrario, Massimo; Clendenin, Jym; Palmer, Dennis; Rosenzweig, James; Serafini, Luca

2000-04-01

The art of designing optimized high brightness electron RF Photo-Injectors has moved in the last decade from a cut and try procedure, guided by experimental experience and time consuming particle tracking simulations, up to a fast parameter space scanning, guided by recent analytical results and a fast running semi-analytical code, so to reach the optimum operating point which corresponds to maximum beam brightness. Scaling laws and the theory of invariant envelope provide to the designers excellent tools for a first parameters choice and the code HOMDYN, based on a multi-slice envelope description of the beam dynamics, is tailored to describe the space charge dominated dynamics of laminar beams in presence of time dependent space charge forces, giving rise to a very fast modeling capability for photo-injectors design. We report in this talk the results of a recent beam dynamics study, motivated by the need to redesign the LCLS photoinjector. During this work a new effective working point for a split RF photoinjector has been discovered by means of the previous mentioned approach. By a proper choice of rf gun and solenoid parameters, the emittance evolution shows a double minimum behavior in the drifting region. If the booster is located where the relative emittance maximum and the envelope waist occur, the second emittance minimum can be shifted at the booster exit and frozen at a very low level (0.3 mm-mrad for a 1 nC flat top bunch), to the extent that the invariant envelope matching conditions are satisfied.

CS2 analysis in presence of non-Gaussian background noise - Effect on traditional estimators and resilience of log-envelope indicators

NASA Astrophysics Data System (ADS)

Borghesani, P.; Antoni, J.

2017-06-01

Second-order cyclostationary (CS2) analysis has become popular in the field of machine diagnostics and a series of digital signal processing techniques have been developed to extract CS2 components from the background noise. Among those techniques, squared envelope spectrum (SES) and cyclic modulation spectrum (CMS) have gained popularity thanks to their high computational efficiency and simple implementation. The effectiveness of CMS and SES has been previously quantified based on the hypothesis of Gaussian background noise and has led to statistical tests for the presence of CS2 peaks in squared envelope spectra and cyclic modulation spectra. However a recently established link of CMS with SES and of SES with kurtosis has exposed a potential weakness of those indicators in the case of highly leptokurtic background noise. This case is often present in practice when the machine is subjected to highly impulsive phenomena, either due to harsh operating conditions or to electric noise generated by power electronics and captured by the sensor. This study investigates and quantifies for the first time the effect of leptokurtic noise on the capabilities of SES and CMS, by analysing three progressively harsh situations: high kurtosis, infinite kurtosis and alpha-stable background noise (for which even first and second-order moments are not defined). Then the resilience of a recently proposed family of CS2 indicators, based on the log-envelope, is verified analytically, numerically and experimentally in the case of highly leptokurtic noise.

Neural correlates of behavioral amplitude modulation sensitivity in the budgerigar midbrain

PubMed Central

Neilans, Erikson G.; Abrams, Kristina S.; Idrobo, Fabio; Carney, Laurel H.

2016-01-01

Amplitude modulation (AM) is a crucial feature of many communication signals, including speech. Whereas average discharge rates in the auditory midbrain correlate with behavioral AM sensitivity in rabbits, the neural bases of AM sensitivity in species with human-like behavioral acuity are unexplored. Here, we used parallel behavioral and neurophysiological experiments to explore the neural (midbrain) bases of AM perception in an avian speech mimic, the budgerigar (Melopsittacus undulatus). Behavioral AM sensitivity was quantified using operant conditioning procedures. Neural AM sensitivity was studied using chronically implanted microelectrodes in awake, unrestrained birds. Average discharge rates of multiunit recording sites in the budgerigar midbrain were insufficient to explain behavioral sensitivity to modulation frequencies <100 Hz for both tone- and noise-carrier stimuli, even with optimal pooling of information across recording sites. Neural envelope synchrony, in contrast, could explain behavioral performance for both carrier types across the full range of modulation frequencies studied (16–512 Hz). The results suggest that envelope synchrony in the budgerigar midbrain may underlie behavioral sensitivity to AM. Behavioral AM sensitivity based on synchrony in the budgerigar, which contrasts with rate-correlated behavioral performance in rabbits, raises the possibility that envelope synchrony, rather than average discharge rate, might also underlie AM perception in other species with sensitive AM detection abilities, including humans. These results highlight the importance of synchrony coding of envelope structure in the inferior colliculus. Furthermore, they underscore potential benefits of devices (e.g., midbrain implants) that evoke robust neural synchrony. PMID:26843608

Effect of core cooling on the radius of sub-Neptune planets

NASA Astrophysics Data System (ADS)

Vazan, A.; Ormel, C. W.; Dominik, C.

2018-02-01

Sub-Neptune planets are very common in our Galaxy and show a large diversity in their mass-radius relation. In sub-Neptunes most of the planet mass is in the rocky part (hereafter, core), which is surrounded by a modest hydrogen-helium envelope. As a result, the total initial heat content of such a planet is dominated by that of the core. Nonetheless, most studies contend that the core cooling only has a minor effect on the radius evolution of the gaseous envelope because the cooling of the core is in sync with the envelope; that is most of the initial heat is released early on timescales of 10-100 Myr. In this Letter we examined the importance of the core cooling rate for the thermal evolution of the envelope. Thus, we relaxed the early core cooling assumption and present a model in which the core is characterized by two parameters: the initial temperature and the cooling time. We find that core cooling can significantly enhance the radius of the planet when it operates on a timescale similar to the observed age, i.e. Gyr. Consequently, the interpretation of the mass-radius observations of sub-Neptunes depends on the assumed core thermal properties and the uncertainty therein. The degeneracy of composition and core thermal properties can be reduced by obtaining better estimates of the planet ages (in addition to their radii and masses) as envisioned by future observations.

Measurement of reach envelopes with a four-camera Selective Spot Recognition (SELSPOT) system

NASA Technical Reports Server (NTRS)

Stramler, J. H., Jr.; Woolford, B. J.

1983-01-01

The basic Selective Spot Recognition (SELSPOT) system is essentially a system which uses infrared LEDs and a 'camera' with an infrared-sensitive photodetector, a focusing lens, and some A/D electronics to produce a digital output representing an X and Y coordinate for each LED for each camera. When the data are synthesized across all cameras with appropriate calibrations, an XYZ set of coordinates is obtained for each LED at a given point in time. Attention is given to the operating modes, a system checkout, and reach envelopes and software. The Video Recording Adapter (VRA) represents the main addition to the basic SELSPOT system. The VRA contains a microprocessor and other electronics which permit user selection of several options and some interaction with the system.

Measuring routine nursing service efficiency: a comparison of cost per patient day and data envelopment analysis models.

PubMed Central

Nunamaker, T R

1983-01-01

This article provides an illustrative application of Data Envelopment Analysis (DEA) methodology to the measurement of routine nursing service efficiency at a group of Wisconsin hospitals. The DEA efficiency ratings and cost savings estimates are then compared to those resulting from application of Medicare's routine cost limitation to the sample data. DEA is also used to determine if any changes in the potential for efficient operations occurred during the 1978-1979 period. Empirical results were representative of the fundamental differences existing between the DEA and cost per patient day approaches. No evidence was found to support the notion that the overall potential for efficient delivery of routine services by the sample institutions was greater in one year than another. PMID:6874357

Office worker response to an automated venetian blind and electric lighting system: A pilot study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vine, E.; Lee, E.; Clear, R.

1998-03-01

A prototype integrated, dynamic building envelope and lighting system designed to optimize daylight admission and solar heat gain rejection on a real-time basis in a commercial office building is evaluated. Office worker response to the system and occupant-based modifications to the control system are investigated to determine if the design and operation of the prototype system can be improved. Key findings from the study are: (1) the prototype integrated envelope and lighting system is ready for field testing, (2) most office workers (N=14) were satisfied with the system, and (3) there were few complaints. Additional studies are needed to explainmore » how illuminance distribution, lighting quality, and room design can affect workplans illuminance preferences.« less

25 CFR 90.43 - Canvass of election returns.

Code of Federal Regulations, 2010 CFR

2010-04-01

... the inner envelope, the voter fails to sign the statement appearing on the outer envelope, and for failure to seal the inner envelope or enclose the inner envelope in the outer envelope. Votes cast for... all other ballots have been counted, the sealed inner envelopes containing the absentee ballots shall...

Processing of spectral and amplitude envelope of animal vocalizations in the human auditory cortex.

PubMed

Altmann, Christian F; Gomes de Oliveira Júnior, Cícero; Heinemann, Linda; Kaiser, Jochen

2010-08-01

In daily life, we usually identify sounds effortlessly and efficiently. Two properties are particularly salient and of importance for sound identification: the sound's overall spectral envelope and its temporal amplitude envelope. In this study, we aimed at investigating the representation of these two features in the human auditory cortex by using a functional magnetic resonance imaging adaptation paradigm. We presented pairs of sound stimuli derived from animal vocalizations that preserved the time-averaged frequency spectrum of the animal vocalizations and the amplitude envelope. We presented the pairs in four different conditions: (a) pairs with the same amplitude envelope and mean spectral envelope, (b) same amplitude envelope, but different mean spectral envelope, (c) different amplitude envelope, but same mean spectral envelope and (d) both different amplitude envelope and mean spectral envelope. We found fMRI adaptation effects for both the mean spectral envelope and the amplitude envelope of animal vocalizations in overlapping cortical areas in the bilateral superior temporal gyrus posterior to Heschl's gyrus. Areas sensitive to the amplitude envelope extended further anteriorly along the lateral superior temporal gyrus in the left hemisphere, while areas sensitive to the spectral envelope extended further anteriorly along the right lateral superior temporal gyrus. Posterior tonotopic areas within the left superior temporal lobe displayed sensitivity for the mean spectrum. Our findings suggest involvement of primary auditory areas in the representation of spectral cues and encoding of general spectro-temporal features of natural sounds in non-primary posterior and lateral superior temporal cortex. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Environmental performance evaluation of large-scale municipal solid waste incinerators using data envelopment analysis.

PubMed

Chen, Ho-Wen; Chang, Ni-Bin; Chen, Jeng-Chung; Tsai, Shu-Ju

2010-07-01

Limited to insufficient land resources, incinerators are considered in many countries such as Japan and Germany as the major technology for a waste management scheme capable of dealing with the increasing demand for municipal and industrial solid waste treatment in urban regions. The evaluation of these municipal incinerators in terms of secondary pollution potential, cost-effectiveness, and operational efficiency has become a new focus in the highly interdisciplinary area of production economics, systems analysis, and waste management. This paper aims to demonstrate the application of data envelopment analysis (DEA)--a production economics tool--to evaluate performance-based efficiencies of 19 large-scale municipal incinerators in Taiwan with different operational conditions. A 4-year operational data set from 2002 to 2005 was collected in support of DEA modeling using Monte Carlo simulation to outline the possibility distributions of operational efficiency of these incinerators. Uncertainty analysis using the Monte Carlo simulation provides a balance between simplifications of our analysis and the soundness of capturing the essential random features that complicate solid waste management systems. To cope with future challenges, efforts in the DEA modeling, systems analysis, and prediction of the performance of large-scale municipal solid waste incinerators under normal operation and special conditions were directed toward generating a compromised assessment procedure. Our research findings will eventually lead to the identification of the optimal management strategies for promoting the quality of solid waste incineration, not only in Taiwan, but also elsewhere in the world. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

High-Volume Airborne Fluids Handling Technologies to Fight Wildfires

NASA Technical Reports Server (NTRS)

Dickerson, Mark; Cox, Timothy; Hale, Cliff; Hatton, Rick

2010-01-01

NASA recently partnered with the U.S. Forest Service (USFS) on a project to examine mission suitability and recommend policies and procedures for the use of very large aerial firefighting aircraft such as the Boeing 747 and DC-10 aerial retardant delivery aircraft. The aircraft under study included a 10Tanker DC-10 and an Evergreen B-747. NASA's Dryden Flight Research Center and Ames Research Center worked with the USFS to help determine the safe flight envelope for these Very Large Air Tanker (VLAT) aircraft for the USFS and the Department of the Interior (DOI). This new generation of supertankers includes aircraft like these that have as much as four times the delivery capacity of the previous generation of aerial firefighting aircraft. Dryden performed operational test and evaluation assessments and reported findings and recommendations on these aircraft in cooperation with Ames. The team developed, implemented, and directed an evaluation test plan for use in flight test and in simulation. Ames provided support using pilot-in-the-loop simulations and coordinated simulator models, flight profiles, and data analysis with Dryden. The test plan was designed to evaluate the suitability of VLAT aircraft as a function of mission environment. Based on this analysis, NASA generated interim flight envelope limitations to enhance safety and operational utility in the fire-retardant delivery mission. These recommended flight limitations were adopted by the USFS. The 10Tanker DC-10 has been in use for several years with the California Department of Forestry and Fire Protection(Cal-Fire), but until NASA took on the challenge of reviewing VLAT capabilities and limitations, the USFS was hesitant to add them to the federal wildfire arsenal. The DC-10 delivery system is based on an externally mounted set of tanks and a bomb-bay style set of clamshell doors that are opened in precisely calibrated ways to deliver the amounts and concentrations of retardant called for by the specific wildfire situation. The system was manufactured by Jordan Air of Central Point, OR, and was installed by Victorville Aerospace in Victorville, CA. It can deliver 12,000 gallons (45.4 kL) of retardant in as little as eight seconds. The aircraft can deliver a partial load of retardant and make multiple drops on the same flight, or the entire load can be rapidly delivered in one pass if required for maximum coverage. The Evergreen 747 uses internal tankage and a pressurized delivery system to enable volume and coverage levels that also meet USFS requirements, but enables computer control of flow for desired precision. This system was designed and built by Adaptive Aerospace of Tehachapi, CA and can deliver about 20,000 gallons (75.7 kL) of retardant in approximately ten seconds. The 747 can also make multiple independent drops, or deliver the entire load at once. NASA found that both of these VLAT aircraft are compatible with the wildfire suppression mission when used to supplement other aerial retardant delivery platforms. The major recommendations for deployment that resulted from this study relate to terrain clearance, the type of terrain in the drop area, availability of qualified lead planes to guide the VLAT approach to the drop area, and low-altitude maneuvering limitations. NASA s analysis suggests that with the appropriate flight procedures, these aircraft will provide a powerful set of tools to fight wildfires.

Computing Bounds on Resource Levels for Flexible Plans

NASA Technical Reports Server (NTRS)

Muscvettola, Nicola; Rijsman, David

2009-01-01

A new algorithm efficiently computes the tightest exact bound on the levels of resources induced by a flexible activity plan (see figure). Tightness of bounds is extremely important for computations involved in planning because tight bounds can save potentially exponential amounts of search (through early backtracking and detection of solutions), relative to looser bounds. The bound computed by the new algorithm, denoted the resource-level envelope, constitutes the measure of maximum and minimum consumption of resources at any time for all fixed-time schedules in the flexible plan. At each time, the envelope guarantees that there are two fixed-time instantiations one that produces the minimum level and one that produces the maximum level. Therefore, the resource-level envelope is the tightest possible resource-level bound for a flexible plan because any tighter bound would exclude the contribution of at least one fixed-time schedule. If the resource- level envelope can be computed efficiently, one could substitute looser bounds that are currently used in the inner cores of constraint-posting scheduling algorithms, with the potential for great improvements in performance. What is needed to reduce the cost of computation is an algorithm, the measure of complexity of which is no greater than a low-degree polynomial in N (where N is the number of activities). The new algorithm satisfies this need. In this algorithm, the computation of resource-level envelopes is based on a novel combination of (1) the theory of shortest paths in the temporal-constraint network for the flexible plan and (2) the theory of maximum flows for a flow network derived from the temporal and resource constraints. The measure of asymptotic complexity of the algorithm is O(N O(maxflow(N)), where O(x) denotes an amount of computing time or a number of arithmetic operations proportional to a number of the order of x and O(maxflow(N)) is the measure of complexity (and thus of cost) of a maximumflow algorithm applied to an auxiliary flow network of 2N nodes. The algorithm is believed to be efficient in practice; experimental analysis shows the practical cost of maxflow to be as low as O(N1.5). The algorithm could be enhanced following at least two approaches. In the first approach, incremental subalgorithms for the computation of the envelope could be developed. By use of temporal scanning of the events in the temporal network, it may be possible to significantly reduce the size of the networks on which it is necessary to run the maximum-flow subalgorithm, thereby significantly reducing the time required for envelope calculation. In the second approach, the practical effectiveness of resource envelopes in the inner loops of search algorithms could be tested for multi-capacity resource scheduling. This testing would include inner-loop backtracking and termination tests and variable and value-ordering heuristics that exploit the properties of resource envelopes more directly.

Spectrum auto-correlation analysis and its application to fault diagnosis of rolling element bearings

NASA Astrophysics Data System (ADS)

Ming, A. B.; Qin, Z. Y.; Zhang, W.; Chu, F. L.

2013-12-01

Bearing failure is one of the most common reasons of machine breakdowns and accidents. Therefore, the fault diagnosis of rolling element bearings is of great significance to the safe and efficient operation of machines owing to its fault indication and accident prevention capability in engineering applications. Based on the orthogonal projection theory, a novel method is proposed to extract the fault characteristic frequency for the incipient fault diagnosis of rolling element bearings in this paper. With the capability of exposing the oscillation frequency of the signal energy, the proposed method is a generalized form of the squared envelope analysis and named as spectral auto-correlation analysis (SACA). Meanwhile, the SACA is a simplified form of the cyclostationary analysis as well and can be iteratively carried out in applications. Simulations and experiments are used to evaluate the efficiency of the proposed method. Comparing the results of SACA, the traditional envelope analysis and the squared envelope analysis, it is found that the result of SACA is more legible due to the more prominent harmonic amplitudes of the fault characteristic frequency and that the SACA with the proper iteration will further enhance the fault features.

Integrated helmet mounted display concepts for air combat

NASA Technical Reports Server (NTRS)

Clark, Joseph W.

1995-01-01

A piloted simulation study was conducted in a dome simulator to evaluate several Helmet Mounted Display (HMD) formats developed as part of the NASA High Alpha Technology Program (HATP). The display formats conveyed energy management, spatial orientation, and weapons management information. The HMD format was compared to a generic Heads Up Display (HUD) typical of current operational fighter aircraft. Pilots were tasked to spend as much time in a weapon solution as possible, to have the correct weapon selected for the envelope they were in, and to avoid the adversary's weapon envelope as much as possible. Several different displays were tested individually and simultaneously to see how separate display concepts coexisted. Objective results showed that the ability for the pilot to select the correct weapon for the envelope he was in increased by 50% in a moderate workload condition and 90% in a high workload condition with the HMD format. In the post-test comments pilots generally favored the helmet display formats over the HUD formats with a few instances where pilots preferred a simple numeric readout of the parameter. Short term exposure effects of the HMD on visual acuity were also measured and showed no advers results.

Envelope analysis of rotating machine vibrations in variable speed conditions: A comprehensive treatment

NASA Astrophysics Data System (ADS)

Abboud, D.; Antoni, J.; Sieg-Zieba, S.; Eltabach, M.

2017-02-01

Nowadays, the vibration analysis of rotating machine signals is a well-established methodology, rooted on powerful tools offered, in particular, by the theory of cyclostationary (CS) processes. Among them, the squared envelope spectrum (SES) is probably the most popular to detect random CS components which are typical symptoms, for instance, of rolling element bearing faults. Recent researches are shifted towards the extension of existing CS tools - originally devised in constant speed conditions - to the case of variable speed conditions. Many of these works combine the SES with computed order tracking after some preprocessing steps. The principal object of this paper is to organize these dispersed researches into a structured comprehensive framework. Three original features are furnished. First, a model of rotating machine signals is introduced which sheds light on the various components to be expected in the SES. Second, a critical comparison is made of three sophisticated methods, namely, the improved synchronous average, the cepstrum prewhitening, and the generalized synchronous average, used for suppressing the deterministic part. Also, a general envelope enhancement methodology which combines the latter two techniques with a time-domain filtering operation is revisited. All theoretical findings are experimentally validated on simulated and real-world vibration signals.

Develop security architecture for both in-house healthcare information systems and electronic patient record

NASA Astrophysics Data System (ADS)

Zhang, Jianguo; Chen, Xiaomeng; Zhuang, Jun; Jiang, Jianrong; Zhang, Xiaoyan; Wu, Dongqing; Huang, H. K.

2003-05-01

In this paper, we presented a new security approach to provide security measures and features in both healthcare information systems (PACS, RIS/HIS), and electronic patient record (EPR). We introduced two security components, certificate authoring (CA) system and patient record digital signature management (DSPR) system, as well as electronic envelope technology, into the current hospital healthcare information infrastructure to provide security measures and functions such as confidential or privacy, authenticity, integrity, reliability, non-repudiation, and authentication for in-house healthcare information systems daily operating, and EPR exchanging among the hospitals or healthcare administration levels, and the DSPR component manages the all the digital signatures of patient medical records signed through using an-symmetry key encryption technologies. The electronic envelopes used for EPR exchanging are created based on the information of signers, digital signatures, and identifications of patient records stored in CAS and DSMS, as well as the destinations and the remote users. The CAS and DSMS were developed and integrated into a RIS-integrated PACS, and the integration of these new security components is seamless and painless. The electronic envelopes designed for EPR were used successfully in multimedia data transmission.

Algebraic special functions and SO(3,2)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Celeghini, E., E-mail: celeghini@fi.infn.it; Olmo, M.A. del, E-mail: olmo@fta.uva.es

2013-06-15

A ladder structure of operators is presented for the associated Legendre polynomials and the sphericas harmonics. In both cases these operators belong to the irreducible representation of the Lie algebra so(3,2) with quadratic Casimir equals to −5/4. As both are also bases of square-integrable functions, the universal enveloping algebra of so(3,2) is thus shown to be homomorphic to the space of linear operators acting on the L{sup 2} functions defined on (−1,1)×Z and on the sphere S{sup 2}, respectively. The presence of a ladder structure is suggested to be the general condition to obtain a Lie algebra representation defining inmore » this way the “algebraic special functions” that are proposed to be the connection between Lie algebras and square-integrable functions so that the space of linear operators on the L{sup 2} functions is homomorphic to the universal enveloping algebra. The passage to the group, by means of the exponential map, shows that the associated Legendre polynomials and the spherical harmonics support the corresponding unitary irreducible representation of the group SO(3,2). -- Highlights: •The algebraic ladder structure is constructed for the associated Legendre polynomials (ALP). •ALP and spherical harmonics support a unitary irreducible SO(3,2)-representation. •A ladder structure is the condition to get a Lie group representation defining “algebraic special functions”. •The “algebraic special functions” connect Lie algebras and L{sup 2} functions.« less

77 FR 69573 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Electronic Flight Control System...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-20

... airplane will have a novel or unusual design feature(s) associated with an electronic flight control system... empennage and control surfaces. The Model EMB-550 airplane is designed for 8 passengers, with a maximum of... flight control design feature within the normal operational envelope in which sidestick deflection in the...

47 CFR 25.218 - Off-axis EIRP envelopes for FSS earth station operations.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Analog video earth station applications, and (3) Applications for feeder-link earth stations in the 17/24...BW/4 kHz For 9.2° 18 dBW/4 kHz For 48° 18 dBW/4 kHz For 48° <θ ≤85° −8 dBW/4 k...

Entirely passive heat pipe apparatus capable of operating against gravity

DOEpatents

Koenig, Daniel R.

1982-01-01

The disclosure is directed to an entirely passive heat pipe apparatus capable of operating against gravity for vertical distances in the order of 3 to 7 meters and more. A return conduit into which an inert gas is introduced is used to lower the specific density of the working fluid so that it may be returned a greater vertical distance from condenser to evaporator.

Entirely passive heat-pipe apparatus capable of operating against gravity

DOEpatents

Koenig, D.R.

1981-02-11

The disclosure is directed to an entirely passive heat pipe apparatus capable of operating against gravity for vertical distances in the order of 3 to 7 and more. A return conduit into which an inert gas is introduced is used to lower the specific density of the working fluid so that it may be returned a greater vertical distance from condenser to evaporator.

Radiological considerations in the operation of the low-energy undulator test line (LEUTL).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moe, H.J.

1998-11-11

The Low-Energy Undulator Test Line (LEUTL) is a facility that uses the existing APS linac to accelerate electrons up to an energy of 700 MeV. These electrons are transported through the Pm into a portion of the booster synchrotrons and on into the LEUTL main enclosure (MIL 97). Figure 1 shows the layout of the LEUTL building, which consists of an earth-benned concrete enclosure and an end-station building. The concrete enclosure houses the electron beamline, test undulator, and beam dump. This facility is about 51 m long and 3.66 m wide. Technical components and diagnostics for characterizing the undulator lightmore » are found in the end station. This building has about 111 m{sup 2} of floor space. This note deals with the radiological considerations of operations using electrons up to 700 MeV and at power levels up to the safety envelope of 1 kW. Previous radiological considerations for electron and positron operations in the linac, PAR, and synchrotrons have been addressed else-where (MOE 93a, 93b, and 93c). Much of the methodology discussed in the previous writeups, as well as in MOE 94, has been used in the computations in this note. The radiological aspects that are addressed include the following: prompt secondary radiation (bremsstrahlung, giant resonance neutrons, medium- and high-energy neutrons) produced by electrons interacting in a beam stop or in component structures; skyshine radiation, which produces a radiation field in nearby areas and at the nearest off-site location; radioactive gases produced by neutron irradiation of air in the vicinity of a particle loss site; noxious gases (ozone and others) produced in air by the escaping bremsstrahlung radiation that results from absorbing particles in the components; activation of the LEUTL components that results in a residual radiation field in the vicinity of these materials following shutdown; potential activation of water used for cooling the magnets and other purposes in the tunnel; and evaluation of the radiation fields due to escaping gas bremsstrahlung. Estimated dose rates have been computed or scaled (in the case of 400 MeV electrons) outside of the bermed tunnel, in Building 412, and in the Klystron Gallery for several modes of operation, including potential safety envelope beam power, normal beam power and MCI (maximum credible incident) conditions. Radiological aspects of shielding changes to the synchrotrons and their effect upon operations are addressed in MOE 97. No change in the safety envelope for synchrotrons operation was warranted.« less

IRC +10 216 in 3D: morphology of a TP-AGB star envelope

NASA Astrophysics Data System (ADS)

Guélin, M.; Patel, N. A.; Bremer, M.; Cernicharo, J.; Castro-Carrizo, A.; Pety, J.; Fonfría, J. P.; Agúndez, M.; Santander-García, M.; Quintana-Lacaci, G.; Velilla Prieto, L.; Blundell, R.; Thaddeus, P.

2018-02-01

During their late pulsating phase, AGB stars expel most of their mass in the form of massive dusty envelopes, an event that largely controls the composition of interstellar matter. The envelopes, however, are distant and opaque to visible and NIR radiation: their structure remains poorly known and the mass-loss process poorly understood. Millimeter-wave interferometry, which combines the advantages of longer wavelength, high angular resolution and very high spectral resolution is the optimal investigative tool for this purpose. Mm waves pass through dust with almost no attenuation. Their spectrum is rich in molecular lines and hosts the fundamental lines of the ubiquitous CO molecule, allowing a tomographic reconstruction of the envelope structure. The circumstellar envelope IRC +10 216 and its central star, the C-rich TP-AGB star closest to the Sun, are the best objects for such an investigation. Two years ago, we reported the first detailed study of the CO(2-1) line emission in that envelope, made with the IRAM 30-m telescope. It revealed a series of dense gas shells, expanding at a uniform radial velocity. The limited resolution of the telescope (HPBW 11″) did not allow us to resolve the shell structure. We now report much higher angular resolution observations of CO(2-1), CO(1-0), CN(2-1) and C4H(24-23) made with the SMA, PdB and ALMA interferometers (with synthesized half-power beamwidths of 3″, 1″ and 0.3″, respectively). Although the envelope appears much more intricate at high resolution than with an 11″ beam, its prevailing structure remains a pattern of thin, nearly concentric shells. The average separation between the brightest CO shells is 16″ in the outer envelope, where it appears remarkably constant. Closer to the star (<40″), the shell pattern is denser and less regular, showing intermediary arcs. Outside the small (r< 0.3'') dust formation zone, the gas appears to expand radially at a constant velocity, 14.5 km s-1, with small turbulent motions. Based on that property, we have reconstructed the 3D structure of the outer envelope and have derived the gas temperature and density radial profiles in the inner (r< 25'') envelope. The shell-intershell density contrast is found to be typically 3. The over-dense shells have spherical or slightly oblate shapes and typically extend over a few steradians, implying isotropic mass loss. The regular spacing of shells in the outer envelope supports the model of a binary star system with a period of 700 yr and a near face-on elliptical orbit. The companion fly-by triggers enhanced episodes of mass loss near periastron. The densification of the shell pattern observed in the central part of the envelope suggests a more complex scenario for the last few thousand years. This work was based on observations carried out with the IRAM, SMA and ALMA telescopes. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). The Submillimeter Array is a joint project between the Smithsonian Astrophysical Observatory (USA) and the Academia Sinica Institute of Astronomy and Astrophysics (Taiwan) and is funded by the Smithsonian Institution and the Academia Sinica. This paper makes use of the ALMA data: ADS/JAO.ALMA#2013.1.01215.S & ADS/JAO.ALMA#2013.1.00432.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), NSC and ASIAA (Taiwan) and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ.

Materials and construction techniques for cryogenic wind tunnel facilities for instruction/research use

NASA Technical Reports Server (NTRS)

Morse, S. F.; Roper, A. T.

1975-01-01

The results of the cryogenic wind tunnel program conducted at NASA Langley Research Center are presented to provide a starting point for the design of an instructional/research wind tunnel facility. The advantages of the cryogenic concept are discussed, and operating envelopes for a representative facility are presented to indicate the range and mode of operation. Special attention is given to the design, construction and materials problems peculiar to cryogenic wind tunnels. The control system for operation of a cryogenic tunnel is considered, and a portion of a linearized mathematical model is developed for determining the tunnel dynamic characteristics.

Quantification of knee vibroarthrographic signal irregularity associated with patellofemoral joint cartilage pathology based on entropy and envelope amplitude measures.

PubMed

Wu, Yunfeng; Chen, Pinnan; Luo, Xin; Huang, Hui; Liao, Lifang; Yao, Yuchen; Wu, Meihong; Rangayyan, Rangaraj M

2016-07-01

Injury of knee joint cartilage may result in pathological vibrations between the articular surfaces during extension and flexion motions. The aim of this paper is to analyze and quantify vibroarthrographic (VAG) signal irregularity associated with articular cartilage degeneration and injury in the patellofemoral joint. The symbolic entropy (SyEn), approximate entropy (ApEn), fuzzy entropy (FuzzyEn), and the mean, standard deviation, and root-mean-squared (RMS) values of the envelope amplitude, were utilized to quantify the signal fluctuations associated with articular cartilage pathology of the patellofemoral joint. The quadratic discriminant analysis (QDA), generalized logistic regression analysis (GLRA), and support vector machine (SVM) methods were used to perform signal pattern classifications. The experimental results showed that the patients with cartilage pathology (CP) possess larger SyEn and ApEn, but smaller FuzzyEn, over the statistical significance level of the Wilcoxon rank-sum test (p<0.01), than the healthy subjects (HS). The mean, standard deviation, and RMS values computed from the amplitude difference between the upper and lower signal envelopes are also consistently and significantly larger (p<0.01) for the group of CP patients than for the HS group. The SVM based on the entropy and envelope amplitude features can provide superior classification performance as compared with QDA and GLRA, with an overall accuracy of 0.8356, sensitivity of 0.9444, specificity of 0.8, Matthews correlation coefficient of 0.6599, and an area of 0.9212 under the receiver operating characteristic curve. The SyEn, ApEn, and FuzzyEn features can provide useful information about pathological VAG signal irregularity based on different entropy metrics. The statistical parameters of signal envelope amplitude can be used to characterize the temporal fluctuations related to the cartilage pathology. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

An Overview of Long Duration Sodium Heat Pipe Tests

NASA Astrophysics Data System (ADS)

Rosenfeld, John H.; Ernst, Donald M.; Lindemuth, James E.; Sanzi, James L.; Geng, Steven M.; Zuo, Jon

2004-02-01

High temperature heat pipes are being evaluated for use in energy conversion applications such as fuel cells, gas turbine re-combustors, and Stirling cycle heat sources; with the resurgence of space nuclear power, additional applications include reactor heat removal elements and radiator elements. Long operating life and reliable performance are critical requirements for these applications. Accordingly long-term materials compatibility is being evaluated through the use of high temperature life test heat pipes. Thermacore, Inc. has carried out several sodium heat pipe life tests to establish long term operating reliability. Four sodium heat pipes have recently demonstrated favorable materials compatibility and heat transport characteristics at high operating temperatures in air over long time periods. A 316L stainless steel heat pipe with a sintered porous nickel wick structure and an integral brazed cartridge heater has successfully operated at 650C to 700C for over 115,000 hours without signs of failure. A second 316L stainless steel heat pipe with a specially-designed Inconel 601 rupture disk and a sintered nickel powder wick has demonstrated over 83,000 hours at 600C to 650C with similar success. A representative one-tenth segment Stirling Space Power Converter heat pipe with an Inconel 718 envelope and a stainless steel screen wick has operated for over 41,000 hours at nearly 700C. A hybrid (i.e. gas-fired and solar) heat pipe with a Haynes 230 envelope and a sintered porous nickel wick structure was operated for about 20,000 hours at nearly 700C without signs of degradation. These life test results collectively have demonstrated the potential for high temperature heat pipes to serve as reliable energy conversion system components for power applications that require long operating lifetime with high reliability. Detailed design specifications, operating history, and test results are described for each of these sodium heat pipes. Lessons learned and future life test plans are also discussed.

An Overview of Long Duration Sodium Heat Pipe Tests

NASA Technical Reports Server (NTRS)

Rosenfeld, John H.; Ernst, Donald M.; Lindemuth, James E.; Sanzi, James L.; Geng, Steven M.; Zuo, Jon

2004-01-01

High temperature heat pipes are being evaluated for use in energy conversion applications such as fuel cells, gas turbine re-combustors, and Stirling cycle heat sources; with the resurgence of space nuclear power, additional applications include reactor heat removal elements and radiator elements. Long operating life and reliable performance are critical requirements for these applications. Accordingly long-term materials compatibility is being evaluated through the use of high temperature life test heat pipes. Thermacore International, Inc., has carried out several sodium heat pipe life tests to establish long term operating reliability. Four sodium heat pipes have recently demonstrated favorable materials compatibility and heat transport characteristics at high operating temperatures in air over long time periods. A 3l6L stainless steel heat pipe with a sintered porous nickel wick structure and an integral brazed cartridge heater has successfully operated at 650 to 700 C for over 115,000 hours without signs of failure. A second 3l6L stainless steel heat pipe with a specially-designed Inconel 60 I rupture disk and a sintered nickel powder wick has demonstrated over 83,000 hours at 600 to 650 C with similar success. A representative one-tenth segment Stirling Space Power Converter heat pipe with an Inconel 718 envelope and a stainless steel screen wick has operated for over 41 ,000 hours at nearly 700 0c. A hybrid (i.e. gas-fired and solar) heat pipe with a Haynes 230 envelope and a sintered porous nickel wick structure was operated for about 20,000 hours at nearly 700 C without signs of degradation. These life test results collectively have demonstrated the potential for high temperature heat pipes to serve as reliable energy conversion system components for power applications that require long operating lifetime with high reliability, Detailed design specifications, operating hi story, and test results are described for each of these sodium heat pipes. Lessons learned and future life test plans are also discussed.

Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert

Science.gov Websites

several years. Golden Eagle will convert all fleet vehicles to CNG in their six branch operations Entire Fleet to CNG Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG to someone by E-mail Share Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert Entire Fleet

Analysis and determination the efficiency of the European health systems.

PubMed

Del Rocío Moreno-Enguix, María; Gómez-Gallego, Juan Cándido; Gómez Gallego, María

2018-01-01

The current economic crisis has increased the interest in analyzing the efficiency of health care systems, as their funding is a very important part of the budgets for different countries. In this work determines the efficiency in the health services in European countries applying data envelopment analysis. In addition, the combined application of data envelopment analysis methods and ACP can provide an evaluation of the efficiency with respect to differently oriented productive health systems in the different countries. The results show that models with a lower level of efficiency are those whose input is beds, followed by the models whose input is physicians. Finally, we apply the AD to select a few simple indicators that facilitate control of the level of operational efficiency of a health system. Copyright © 2017 John Wiley & Sons, Ltd.

Short pulse generation from a passively mode-locked fiber optical parametric oscillator with optical time-stretch.

PubMed

Qiu, Yi; Wei, Xiaoming; Du, Shuxin; Wong, Kenneth K Y; Tsia, Kevin K; Xu, Yiqing

2018-04-16

We propose a passively mode-locked fiber optical parametric oscillator assisted with optical time-stretch. Thanks to the lately developed optical time-stretch technique, the onset oscillating spectral components can be temporally dispersed across the pump envelope and further compete for the parametric gain with the other parts of onset oscillating sidebands within the pump envelope. By matching the amount of dispersion in optical time-stretch with the pulse width of the quasi-CW pump and oscillating one of the parametric sidebands inside the fiber cavity, we numerically show that the fiber parametric oscillator can be operated in a single pulse regime. By varying the amount of the intracavity dispersion, we further verify that the origin of this single pulse mode-locking regime is due to the optical pulse stretching and compression.

The abundance of 28Si32S, 29Si32S, 28Si34S, and 30Si32S in the inner layers of the envelope of IRC+10216

PubMed Central

Fonfría, J. P.; Cernicharo, J.; Richter, M. J.; Fernández-López, M.; Prieto, L. Velilla; Lacy, J. H.

2016-01-01

We present high spectral resolution mid-IR observations of SiS towards the C-rich AGB star IRC+10216 carried out with the Texas Echelon-cross-Echelle Spectrograph mounted on the NASA Infrared Telescope Facility. We have identified 204 ro-vibrational lines of 28Si32S, 26 of 29Si32S, 20 of 28Si34S, and 15 of 30Si32S in the frequency range 720 – 790 cm−1. These lines belong to bands v = 1 – 0, 2 – 1, 3 – 2, 4–3, and 5–4, and involve rotational levels with Jlow ≲ 90. About 30 per cent of these lines are unblended or weakly blended and can be partially or entirely fitted with a code developed to model the mid-IR emission of a spherically symmetric circumstellar envelope composed of expanding gas and dust. The observed lines trace the envelope at distances to the star ≲ 35R⋆(≃ 0″.7). The fits are compatible with an expansion velocity of 1+2.5(r/R⋆ −1) km s−1 between 1 and 5R⋆, 11 km s−1 between 5 and 20R⋆, and 14.5 km s−1 outwards. The derived abundance profile of 28Si32S with respect to H2 is 4.9 × 10−6 between the stellar photosphere and 5R⋆, decreasing linearly down to 1.6 × 10−6 at 20R⋆ and to 1.3 × 10−6 at 50R⋆. 28Si32S seems to be rotationally under LTE in the region of the envelope probed with our observations and vibrationally out of LTE in most of it. There is a red-shifted emission excess in the 28Si32S lines of band v = 1 – 0 that cannot be found in the lines of bands v = 2 – 1, 3 – 2, 4 – 3, and 5 – 4. This excess could be explained by an enhancement of the vibrational temperature around 20R⋆ behind the star. The derived isotopic ratios 28Si/29Si, and 32S/34S are 17 and 14, compatible with previous estimates. PMID:26997679

The abundance of 28Si32S, 29Si32S, 28Si34S, and 30Si32S in the inner layers of the envelope of IRC+10216.

PubMed

Fonfría, J P; Cernicharo, J; Richter, M J; Fernández-López, M; Prieto, L Velilla; Lacy, J H

2015-08-13

We present high spectral resolution mid-IR observations of SiS towards the C-rich AGB star IRC+10216 carried out with the Texas Echelon-cross-Echelle Spectrograph mounted on the NASA Infrared Telescope Facility. We have identified 204 ro-vibrational lines of 28 Si 32 S, 26 of 29 Si 32 S, 20 of 28 Si 34 S, and 15 of 30 Si 32 S in the frequency range 720 - 790 cm -1 . These lines belong to bands v = 1 - 0, 2 - 1, 3 - 2, 4-3, and 5-4, and involve rotational levels with J low ≲ 90. About 30 per cent of these lines are unblended or weakly blended and can be partially or entirely fitted with a code developed to model the mid-IR emission of a spherically symmetric circumstellar envelope composed of expanding gas and dust. The observed lines trace the envelope at distances to the star ≲ 35 R ⋆ (≃ 0″.7). The fits are compatible with an expansion velocity of 1+2.5( r / R ⋆ -1) km s -1 between 1 and 5 R ⋆ , 11 km s -1 between 5 and 20 R ⋆ , and 14.5 km s -1 outwards. The derived abundance profile of 28 Si 32 S with respect to H 2 is 4.9 × 10 -6 between the stellar photosphere and 5 R ⋆ , decreasing linearly down to 1.6 × 10 -6 at 20 R ⋆ and to 1.3 × 10 -6 at 50 R ⋆ . 28 Si 32 S seems to be rotationally under LTE in the region of the envelope probed with our observations and vibrationally out of LTE in most of it. There is a red-shifted emission excess in the 28 Si 32 S lines of band v = 1 - 0 that cannot be found in the lines of bands v = 2 - 1, 3 - 2, 4 - 3, and 5 - 4. This excess could be explained by an enhancement of the vibrational temperature around 20 R ⋆ behind the star. The derived isotopic ratios 28 Si/ 29 Si, and 32 S/ 34 S are 17 and 14, compatible with previous estimates.

Next Generation Nuclear Plant Methods Research and Development Technical Program Plan -- PLN-2498

DOE Office of Scientific and Technical Information (OSTI.GOV)

Richard R. Schultz; Abderrafi M. Ougouag; David W. Nigg

2008-09-01

One of the great challenges of designing and licensing the Very High Temperature Reactor (VHTR) is to confirm that the intended VHTR analysis tools can be used confidently to make decisions and to assure all that the reactor systems are safe and meet the performance objectives of the Generation IV Program. The research and development (R&D) projects defined in the Next Generation Nuclear Plant (NGNP) Design Methods Development and Validation Program will ensure that the tools used to perform the required calculations and analyses can be trusted. The Methods R&D tasks are designed to ensure that the calculational envelope ofmore » the tools used to analyze the VHTR reactor systems encompasses, or is larger than, the operational and transient envelope of the VHTR itself. The Methods R&D focuses on the development of tools to assess the neutronic and thermal fluid behavior of the plant. The fuel behavior and fission product transport models are discussed in the Advanced Gas Reactor (AGR) program plan. Various stress analysis and mechanical design tools will also need to be developed and validated and will ultimately also be included in the Methods R&D Program Plan. The calculational envelope of the neutronics and thermal-fluids software tools intended to be used on the NGNP is defined by the scenarios and phenomena that these tools can calculate with confidence. The software tools can only be used confidently when the results they produce have been shown to be in reasonable agreement with first-principle results, thought-problems, and data that describe the “highly ranked” phenomena inherent in all operational conditions and important accident scenarios for the VHTR.« less

Next Generation Nuclear Plant Methods Technical Program Plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Richard R. Schultz; Abderrafi M. Ougouag; David W. Nigg

2010-12-01

One of the great challenges of designing and licensing the Very High Temperature Reactor (VHTR) is to confirm that the intended VHTR analysis tools can be used confidently to make decisions and to assure all that the reactor systems are safe and meet the performance objectives of the Generation IV Program. The research and development (R&D) projects defined in the Next Generation Nuclear Plant (NGNP) Design Methods Development and Validation Program will ensure that the tools used to perform the required calculations and analyses can be trusted. The Methods R&D tasks are designed to ensure that the calculational envelope ofmore » the tools used to analyze the VHTR reactor systems encompasses, or is larger than, the operational and transient envelope of the VHTR itself. The Methods R&D focuses on the development of tools to assess the neutronic and thermal fluid behavior of the plant. The fuel behavior and fission product transport models are discussed in the Advanced Gas Reactor (AGR) program plan. Various stress analysis and mechanical design tools will also need to be developed and validated and will ultimately also be included in the Methods R&D Program Plan. The calculational envelope of the neutronics and thermal-fluids software tools intended to be used on the NGNP is defined by the scenarios and phenomena that these tools can calculate with confidence. The software tools can only be used confidently when the results they produce have been shown to be in reasonable agreement with first-principle results, thought-problems, and data that describe the “highly ranked” phenomena inherent in all operational conditions and important accident scenarios for the VHTR.« less

Next Generation Nuclear Plant Methods Technical Program Plan -- PLN-2498

DOE Office of Scientific and Technical Information (OSTI.GOV)

Richard R. Schultz; Abderrafi M. Ougouag; David W. Nigg

2010-09-01

One of the great challenges of designing and licensing the Very High Temperature Reactor (VHTR) is to confirm that the intended VHTR analysis tools can be used confidently to make decisions and to assure all that the reactor systems are safe and meet the performance objectives of the Generation IV Program. The research and development (R&D) projects defined in the Next Generation Nuclear Plant (NGNP) Design Methods Development and Validation Program will ensure that the tools used to perform the required calculations and analyses can be trusted. The Methods R&D tasks are designed to ensure that the calculational envelope ofmore » the tools used to analyze the VHTR reactor systems encompasses, or is larger than, the operational and transient envelope of the VHTR itself. The Methods R&D focuses on the development of tools to assess the neutronic and thermal fluid behavior of the plant. The fuel behavior and fission product transport models are discussed in the Advanced Gas Reactor (AGR) program plan. Various stress analysis and mechanical design tools will also need to be developed and validated and will ultimately also be included in the Methods R&D Program Plan. The calculational envelope of the neutronics and thermal-fluids software tools intended to be used on the NGNP is defined by the scenarios and phenomena that these tools can calculate with confidence. The software tools can only be used confidently when the results they produce have been shown to be in reasonable agreement with first-principle results, thought-problems, and data that describe the “highly ranked” phenomena inherent in all operational conditions and important accident scenarios for the VHTR.« less

Morphology-based three-dimensional segmentation of coronary artery tree from CTA scans

NASA Astrophysics Data System (ADS)

Banh, Diem Phuc T.; Kyprianou, Iacovos S.; Paquerault, Sophie; Myers, Kyle J.

2007-03-01

We developed an algorithm based on a rule-based threshold framework to segment the coronary arteries from angiographic computed tomography (CTA) data. Computerized segmentation of the coronary arteries is a challenging procedure due to the presence of diverse anatomical structures surrounding the heart on cardiac CTA data. The proposed algorithm incorporates various levels of image processing and organ information including region, connectivity and morphology operations. It consists of three successive stages. The first stage involves the extraction of the three-dimensional scaffold of the heart envelope. This stage is semiautomatic requiring a reader to review the CTA scans and manually select points along the heart envelope in slices. These points are further processed using a surface spline-fitting technique to automatically generate the heart envelope. The second stage consists of segmenting the left heart chambers and coronary arteries using grayscale threshold, size and connectivity criteria. This is followed by applying morphology operations to further detach the left and right coronary arteries from the aorta. In the final stage, the 3D vessel tree is reconstructed and labeled using an Isolated Connected Threshold technique. The algorithm was developed and tested on a patient coronary artery CTA that was graciously shared by the Department of Radiology of the Massachusetts General Hospital. The test showed that our method constantly segmented the vessels above 79% of the maximum gray-level and automatically extracted 55 of the 58 coronary segments that can be seen on the CTA scan by a reader. These results are an encouraging step toward our objective of generating high resolution models of the male and female heart that will be subsequently used as phantoms for medical imaging system optimization studies.

Measuring Efficiency of Knowledge Production in Health Research Centers Using Data Envelopment Analysis (DEA): A Case Study in Iran.

PubMed

Amiri, Mohammad Meskarpour; Nasiri, Taha; Saadat, Seyed Hassan; Anabad, Hosein Amini; Ardakan, Payman Mahboobi

2016-11-01

Efficiency analysis is necessary in order to avoid waste of materials, energy, effort, money, and time during scientific research. Therefore, analyzing efficiency of knowledge production in health areas is necessary, especially for developing and in-transition countries. As the first step in this field, the aim of this study was the analysis of selected health research center efficiency using data envelopment analysis (DEA). This retrospective and applied study was conducted in 2015 using input and output data of 16 health research centers affiliated with a health sciences university in Iran during 2010-2014. The technical efficiency of health research centers was evaluated based on three basic data envelopment analysis (DEA) models: input-oriented, output-oriented, and hyperbolic-oriented. The input and output data of each health research center for years 2010-2014 were collected from the Iran Ministry of Health and Medical Education (MOHE) profile and analyzed by R software. The mean efficiency score in input-oriented, output-oriented, and hyperbolic-oriented models was 0.781, 0.671, and 0.798, respectively. Based on results of the study, half of the health research centers are operating below full efficiency, and about one-third of them are operating under the average efficiency level. There is also a large gap between health research center efficiency relative to each other. It is necessary for health research centers to improve their efficiency in knowledge production through better management of available resources. The higher level of efficiency in a significant number of health research centers is achievable through more efficient management of human resources and capital. Further research is needed to measure and follow the efficiency of knowledge production by health research centers around the world and over a period of time.

Remote monitoring of sub ppb levels of vinyl chloride, dichloroethylene and trichloroethylene via modem operated automated GC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Linenberg, A.; Lander, N.J.

1994-12-31

The need for remote monitoring of certain compounds in a sparsely populated area with limited user assistance led to the development and manufacture of a self contained, portable gas chromatography with the appropriate software. Part per billion levels of vinyl chloride, cis 1,2 dichloroethylene and trichloroethylene were detected in air using a trap for preconcentration of the compounds. The units were continuously calibrated with certified standards from Scott Specialty Gases, which in one case was 1 part per billion of the aforementioned compounds. The entire operation of the units, including monitoring instrument responses, changing operating parameters, data transfer, data reviewmore » and data reporting was done entirely on a remote basis from approximately 600 miles away using a remote computer with a modem and remote operating software. The entire system concept promises the availability of highly sensitive remote monitoring in sparsely populated areas for long periods of time.« less

Construction of protocellular structures under simulated primitive earth conditions

NASA Astrophysics Data System (ADS)

Yanagawa, Hiroshi; Ogawa, Yoko; Kojima, Kiyotsugu; Ito, Masahiko

1988-09-01

We have developed experimental approaches for the construction of protocellular structures under simulated primitive earth conditions and studied their formation and characteristics. Three types of envelopes; protein envelopes, lipid envelopes, and lipid-protein envelopes are considered as candidates for protocellular structures. Simple protein envelopes and lipid envelopes are presumed to have originated at an early stage of chemical evolution, interaction mutually and then evolved into more complex envelopes composed of both lipids and proteins. Three kinds of protein envelopes were constructedin situ from amino acids under simulated primitive earth conditions such as a fresh water tide pool, a warm sea, and a submarine hydrothermal vent. One protein envelope was formed from a mixture of amino acid amides at 80 °C using multiple hydration-dehydration cycles. Marigranules, protein envelope structures, were produced from mixtures of glycine and acidic, basic and aromatic amino acids at 105 °C in a modified sea medium enriched with essential transition elements. Thermostable microspheres were also formed from a mixture of glycine, alanine, valine, and aspartic acid at 250 °C and above. The microspheres did not form at lower temperatures and consist of silicates and peptide-like polymers containing imide bonds and amino acid residues enriched in valine. Amphiphilic proteins with molecular weights of 2000 were necessary for the formation of the protein envelopes. Stable lipid envelopes were formed from different dialkyl phospholipids and fatty acids. Large, stable, lipid-protein envelopes were formed from egg lecithin and the solubilized marigranules. Polycations such as polylysine and polyhistidine, or basic proteins such as lysozyme and cytochromec also stabilized lipid-protein envelopes.

Process envelopes for stabilisation/solidification of contaminated soil using lime-slag blend.

PubMed

Kogbara, Reginald B; Yi, Yaolin; Al-Tabbaa, Abir

2011-09-01

Stabilisation/solidification (S/S) has emerged as an efficient and cost-effective technology for the treatment of contaminated soils. However, the performance of S/S-treated soils is governed by several intercorrelated variables, which complicates the optimisation of the treatment process design. Therefore, it is desirable to develop process envelopes, which define the range of operating variables that result in acceptable performance. In this work, process envelopes were developed for S/S treatment of contaminated soil with a blend of hydrated lime (hlime) and ground granulated blast furnace slag (GGBS) as the binder (hlime/GGBS = 1:4). A sand contaminated with a mixture of heavy metals and petroleum hydrocarbons was treated with 5%, 10% and 20% binder dosages, at different water contents. The effectiveness of the treatment was assessed using unconfined compressive strength (UCS), permeability, acid neutralisation capacity and contaminant leachability with pH, at set periods. The UCS values obtained after 28 days of treatment were up to ∼800 kPa, which is quite low, and permeability was ∼10(-8) m/s, which is higher than might be required. However, these values might be acceptable in some scenarios. The binder significantly reduced the leachability of cadmium and nickel. With the 20% dosage, both metals met the waste acceptance criteria for inert waste landfill and relevant environmental quality standards. The results show that greater than 20% dosage would be required to achieve a balance of acceptable mechanical and leaching properties. Overall, the process envelopes for different performance criteria depend on the end-use of the treated material.

Compensating Atmospheric Turbulence Effects at High Zenith Angles with Adaptive Optics Using Advanced Phase Reconstructors

NASA Astrophysics Data System (ADS)

Roggemann, M.; Soehnel, G.; Archer, G.

Atmospheric turbulence degrades the resolution of images of space objects far beyond that predicted by diffraction alone. Adaptive optics telescopes have been widely used for compensating these effects, but as users seek to extend the envelopes of operation of adaptive optics telescopes to more demanding conditions, such as daylight operation, and operation at low elevation angles, the level of compensation provided will degrade. We have been investigating the use of advanced wave front reconstructors and post detection image reconstruction to overcome the effects of turbulence on imaging systems in these more demanding scenarios. In this paper we show results comparing the optical performance of the exponential reconstructor, the least squares reconstructor, and two versions of a reconstructor based on the stochastic parallel gradient descent algorithm in a closed loop adaptive optics system using a conventional continuous facesheet deformable mirror and a Hartmann sensor. The performance of these reconstructors has been evaluated under a range of source visual magnitudes and zenith angles ranging up to 70 degrees. We have also simulated satellite images, and applied speckle imaging, multi-frame blind deconvolution algorithms, and deconvolution algorithms that presume the average point spread function is known to compute object estimates. Our work thus far indicates that the combination of adaptive optics and post detection image processing will extend the useful envelope of the current generation of adaptive optics telescopes.

Application of an Optimal Tuner Selection Approach for On-Board Self-Tuning Engine Models

NASA Technical Reports Server (NTRS)

Simon, Donald L.; Armstrong, Jeffrey B.; Garg, Sanjay

2012-01-01

An enhanced design methodology for minimizing the error in on-line Kalman filter-based aircraft engine performance estimation applications is presented in this paper. It specific-ally addresses the under-determined estimation problem, in which there are more unknown parameters than available sensor measurements. This work builds upon an existing technique for systematically selecting a model tuning parameter vector of appropriate dimension to enable estimation by a Kalman filter, while minimizing the estimation error in the parameters of interest. While the existing technique was optimized for open-loop engine operation at a fixed design point, in this paper an alternative formulation is presented that enables the technique to be optimized for an engine operating under closed-loop control throughout the flight envelope. The theoretical Kalman filter mean squared estimation error at a steady-state closed-loop operating point is derived, and the tuner selection approach applied to minimize this error is discussed. A technique for constructing a globally optimal tuning parameter vector, which enables full-envelope application of the technology, is also presented, along with design steps for adjusting the dynamic response of the Kalman filter state estimates. Results from the application of the technique to linear and nonlinear aircraft engine simulations are presented and compared to the conventional approach of tuner selection. The new methodology is shown to yield a significant improvement in on-line Kalman filter estimation accuracy.

The structure of common-envelope remnants

NASA Astrophysics Data System (ADS)

Hall, Philip D.

2015-05-01

We investigate the structure and evolution of the remnants of common-envelope evolution in binary star systems. In a common-envelope phase, two stars become engulfed in a gaseous envelope and, under the influence of drag forces, spiral to smaller separations. They may merge to form a single star or the envelope may be ejected to leave the stars in a shorter period orbit. This process explains the short orbital periods of many observed binary systems, such as cataclysmic variables and low-mass X-ray binary systems. Despite the importance of these systems, and of common-envelope evolution to their formation, it remains poorly understood. Specifically, we are unable to confidently predict the outcome of a common-envelope phase from the properties at its onset. After presenting a review of work on stellar evolution, binary systems, common-envelope evolution and the computer programs used, we describe the results of three computational projects on common-envelope evolution. Our work specifically relates to the methods and prescriptions which are used for predicting the outcome. We use the Cambridge stellar-evolution code STARS to produce detailed models of the structure and evolution of remnants of common-envelope evolution. We compare different assumptions about the uncertain end-of-common envelope structure and envelope mass of remnants which successfully eject their common envelopes. In the first project, we use detailed remnant models to investigate whether planetary nebulae are predicted after common-envelope phases initiated by low-mass red giants. We focus on the requirement that a remnant evolves rapidly enough to photoionize the nebula and compare the predictions for different ideas about the structure at the end of a common-envelope phase. We find that planetary nebulae are possible for some prescriptions for the end-of-common envelope structure. In our second contribution, we compute a large set of single-star models and fit new formulae to the core radii of evolved stars. These formulae can be used to better compute the outcome of common-envelope evolution with rapid evolution codes. We find that the new formulae are necessary for accurate predictions of the properties of post-common envelope systems. Finally, we use detailed remnant models of massive stars to investigate whether hydrogen may be retained after a common-envelope phase to the point of core-collapse and so be observable in supernovae. We find that this is possible and thus common-envelope evolution may contribute to the formation of Type IIb supernovae.

CPLOAS_2 user manual

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sallaberry, Cedric Jean-Marie.; Helton, Jon Craig

2012-10-01

Weak link (WL)/strong link (SL) systems are important parts of the overall operational design of high-consequence systems. In such designs, the SL system is very robust and is intended to permit operation of the entire system under, and only under, intended conditions. In contrast, the WL system is intended to fail in a predictable and irreversible manner under accident conditions and render the entire system inoperable before an accidental operation of the SL system. The likelihood that the WL system will fail to deactivate the entire system before the SL system fails (i.e., degrades into a configuration that could allowmore » an accidental operation of the entire system) is referred to as probability of loss of assured safety (PLOAS). This report describes the Fortran 90 program CPLOAS_2 that implements the following representations for PLOAS for situations in which both link physical properties and link failure properties are time-dependent: (i) failure of all SLs before failure of any WL, (ii) failure of any SL before failure of any WL, (iii) failure of all SLs before failure of all WLs, and (iv) failure of any SL before failure of all WLs. The effects of aleatory uncertainty and epistemic uncertainty in the definition and numerical evaluation of PLOAS can be included in the calculations performed by CPLOAS_2.« less

Feasibility Study of Endo- and Exo-skeletal Framed Structures with Envelopes for LTA Platforms

DTIC Science & Technology

2011-02-15

pathway for design and fabrication of Endo- and Exoskeleton framed elliptical envelopes was demonstrated. Envelope sizes of 2 ft x 0.5 ft and 5 ft x...Lighter than air, Endoskeleton, Exoskeleton , Helium filled envelope, Design, Fabrication Robert Sadler and Raghu Panduranga ARIS Inc 115-C, South...Structures with Envelopes for LTA Platforms Report Title ABSTRACT A pathway for design and fabrication of Endo- and Exoskeleton framed elliptical envelopes

Cortical processing of dynamic sound envelope transitions.

PubMed

Zhou, Yi; Wang, Xiaoqin

2010-12-08

Slow envelope fluctuations in the range of 2-20 Hz provide important segmental cues for processing communication sounds. For a successful segmentation, a neural processor must capture envelope features associated with the rise and fall of signal energy, a process that is often challenged by the interference of background noise. This study investigated the neural representations of slowly varying envelopes in quiet and in background noise in the primary auditory cortex (A1) of awake marmoset monkeys. We characterized envelope features based on the local average and rate of change of sound level in envelope waveforms and identified envelope features to which neurons were selective by reverse correlation. Our results showed that envelope feature selectivity of A1 neurons was correlated with the degree of nonmonotonicity in their static rate-level functions. Nonmonotonic neurons exhibited greater feature selectivity than monotonic neurons in quiet and in background noise. The diverse envelope feature selectivity decreased spike-timing correlation among A1 neurons in response to the same envelope waveforms. As a result, the variability, but not the average, of the ensemble responses of A1 neurons represented more faithfully the dynamic transitions in low-frequency sound envelopes both in quiet and in background noise.

Estimation of the Scatterer Distribution of the Cirrhotic Liver using Ultrasonic Image

NASA Astrophysics Data System (ADS)

Yamaguchi, Tadashi; Hachiya, Hiroyuki

1998-05-01

In the B-mode image of the liver obtained by an ultrasonic imaging system, the speckled pattern changes with the progression of the disease such as liver cirrhosis.In this paper we present the statistical characteristics of the echo envelope of the liver, and the technique to extract information of the scatterer distribution from the normal and cirrhotic liver images using constant false alarm rate (CFAR) processing.We analyze the relationship between the extracted scatterer distribution and the stage of liver cirrhosis. The ratio of the area in which the amplitude of the processing signal is more than the threshold to the entire processed image area is related quantitatively to the stage of liver cirrhosis.It is found that the proposed technique is valid for the quantitative diagnosis of liver cirrhosis.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dyson, Anna

Intelligent Facades for High Performance Green Buildings: Previous research and development of intelligent facades systems has been limited in their contribution towards national goals for achieving on-site net zero buildings, because this R&D has failed to couple the many qualitative requirements of building envelopes such as the provision of daylighting, access to exterior views, satisfying aesthetic and cultural characteristics, with the quantitative metrics of energy harvesting, storage and redistribution. To achieve energy self-sufficiency from on-site solar resources, building envelopes can and must address this gamut of concerns simultaneously. With this project, we have undertaken a high-performance building- integrated combined-heat andmore » power concentrating photovoltaic system with high temperature thermal capture, storage and transport towards multiple applications (BICPV/T). The critical contribution we are offering with the Integrated Concentrating Solar Façade (ICSF) is conceived to improve daylighting quality for improved health of occupants and mitigate solar heat gain while maximally capturing and transferring on- site solar energy. The ICSF accomplishes this multi-functionality by intercepting only the direct-normal component of solar energy (which is responsible for elevated cooling loads) thereby transforming a previously problematic source of energy into a high- quality resource that can be applied to building demands such as heating, cooling, dehumidification, domestic hot water, and possible further augmentation of electrical generation through organic Rankine cycles. With the ICSF technology, our team is addressing the global challenge in transitioning commercial and residential building stock towards on-site clean energy self-sufficiency, by fully integrating innovative environmental control systems strategies within an intelligent and responsively dynamic building envelope. The advantage of being able to use the entire solar spectrum for active and passive benefits, along with the potential savings of avoiding transmission losses through direct current (DC) transfer to all buildings systems directly from the site of solar conversion, gives the system a compounded economic viability within the commercial and institutional building markets.« less

GIANT IMPACT: AN EFFICIENT MECHANISM FOR THE DEVOLATILIZATION OF SUPER-EARTHS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Shang-Fei; Hori, Yasunori; Lin, D. N. C.

Mini-Neptunes and volatile-poor super-Earths coexist on adjacent orbits in proximity to host stars such as Kepler-36 and Kepler-11. Several post-formation processes have been proposed for explaining the origin of the compositional diversity between neighboring planets: mass loss via stellar XUV irradiation, degassing of accreted material, and in situ accumulation of the disk gas. Close-in planets are also likely to experience giant impacts during the advanced stage of planet formation. This study examines the possibility of transforming volatile-rich super-Earths/mini-Neptunes into volatile-depleted super-Earths through giant impacts. We present the results of three-dimensional hydrodynamic simulations of giant impacts in the accretionary and disruptivemore » regimes. Target planets are modeled with a three-layered structure composed of an iron core, silicate mantle, and hydrogen/helium envelope. In the disruptive case, the giant impact can remove most of the H/He atmosphere immediately and homogenize the refractory material in the planetary interior. In the accretionary case, the planet is able to retain more than half of the original gaseous envelope, while a compositional gradient suppresses efficient heat transfer as the planetary interior undergoes double-diffusive convection. After the giant impact, a hot and inflated planet cools and contracts slowly. The extended atmosphere enhances the mass loss via both a Parker wind induced by thermal pressure and hydrodynamic escape driven by the stellar XUV irradiation. As a result, the entire gaseous envelope is expected to be lost due to the combination of those processes in both cases. Based on our results, we propose that Kepler-36b may have been significantly devolatilized by giant impacts, while a substantial fraction of Kepler-36c’s atmosphere may remain intact. Furthermore, the stochastic nature of giant impacts may account for the observed large dispersion in the mass–radius relationship of close-in super-Earths and mini-Neptunes (at least to some extent)« less

A Monte Carlo Analysis of the Thrust Imbalance for the RSRMV Booster During Both the Ignition Transient and Steady State Operation

NASA Technical Reports Server (NTRS)

Foster, Winfred A., Jr.; Crowder, Winston; Steadman, Todd E.

2014-01-01

This paper presents the results of statistical analyses performed to predict the thrust imbalance between two solid rocket motor boosters to be used on the Space Launch System (SLS) vehicle. Two legacy internal ballistics codes developed for the Space Shuttle program were coupled with a Monte Carlo analysis code to determine a thrust imbalance envelope for the SLS vehicle based on the performance of 1000 motor pairs. Thirty three variables which could impact the performance of the motors during the ignition transient and thirty eight variables which could impact the performance of the motors during steady state operation of the motor were identified and treated as statistical variables for the analyses. The effects of motor to motor variation as well as variations between motors of a single pair were included in the analyses. The statistical variations of the variables were defined based on data provided by NASA's Marshall Space Flight Center for the upgraded five segment booster and from the Space Shuttle booster when appropriate. The results obtained for the statistical envelope are compared with the design specification thrust imbalance limits for the SLS launch vehicle

A Monte Carlo Analysis of the Thrust Imbalance for the Space Launch System Booster During Both the Ignition Transient and Steady State Operation

NASA Technical Reports Server (NTRS)

Foster, Winfred A., Jr.; Crowder, Winston; Steadman, Todd E.

2014-01-01

This paper presents the results of statistical analyses performed to predict the thrust imbalance between two solid rocket motor boosters to be used on the Space Launch System (SLS) vehicle. Two legacy internal ballistics codes developed for the Space Shuttle program were coupled with a Monte Carlo analysis code to determine a thrust imbalance envelope for the SLS vehicle based on the performance of 1000 motor pairs. Thirty three variables which could impact the performance of the motors during the ignition transient and thirty eight variables which could impact the performance of the motors during steady state operation of the motor were identified and treated as statistical variables for the analyses. The effects of motor to motor variation as well as variations between motors of a single pair were included in the analyses. The statistical variations of the variables were defined based on data provided by NASA's Marshall Space Flight Center for the upgraded five segment booster and from the Space Shuttle booster when appropriate. The results obtained for the statistical envelope are compared with the design specification thrust imbalance limits for the SLS launch vehicle.

Low-Power Ion Thruster Development Status

NASA Technical Reports Server (NTRS)

Patterson, Michael J.

1999-01-01

An effort is on-going to examine scaling relationships and design criteria for ion propulsion systems, and to address the need for a light weight, low power, high specific impulse propulsion option for small spacecraft. An element of this activity is the development of a low-power (sub-0.5 kW) ion thruster. This development effort has led to the fabrication and preliminary performance assessment of an 8 cm prototype xenon ion thruster operating over an input power envelope of 0.1-0.3 kW. Efficiencies for the thruster vary from 0.31 at 1750 seconds specific impulse at 0.1 kW, to about 0.48 at 2700 seconds specific impulse and 0.3 kW input power. Discharge losses for the thruster over this power range varied from about 320-380 W/A down to about 220-250 W/A. Ion optics performance compare favorably to that obtained with 30 cm ion optics, when scaled for the difference in beam area. The neutralizer, fabricated using 3 mm hollow cathode technology, operated at keeper currents of about 0.2-0.3 A, at a xenon flow rate of about 0.06 mg/s, over the 0.1-0.3 kW thruster input power envelope.

Personnel occupied woven envelope robot

NASA Technical Reports Server (NTRS)

Wessling, Francis; Teoh, William; Ziemke, M. Carl

1988-01-01

The Personnel Occupied Woven Envelope Robot (POWER) provides an alternative to extravehicular activity (EVA) of space suited astronauts and/or use of long slender manipulator arms such as are used in the Shuttle Remote Manipulator System. POWER provides the capability for a shirt sleeved astronaut to perform such work by entering a control pod through air locks at both ends of an inflated flexible bellows (access tunnel). The exoskeleton of the tunnel is a series of six degrees of freedom (Six-DOF) articulated links compressible to 1/6 of their fully extended length. The operator can maneuver the control pod to almost any location within about 50 m of the base attachment to the space station. POWER can be envisioned as a series of hollow Six-DOF manipulator segments or arms wherein each arm grasps the shoulder of the next arm. Inside the hollow arms ia a bellow-type access tunnel. The control pod is the fist of the series of linked hollow arms. The fingers of the fist are conventional manipulator arms under direct visual control of the nearby operator in the pod. The applications and progress to date of the POWER system is given.

Real-time Terrain Relative Navigation Test Results from a Relevant Environment for Mars Landing

NASA Technical Reports Server (NTRS)

Johnson, Andrew E.; Cheng, Yang; Montgomery, James; Trawny, Nikolas; Tweddle, Brent; Zheng, Jason

2015-01-01

Terrain Relative Navigation (TRN) is an on-board GN&C function that generates a position estimate of a spacecraft relative to a map of a planetary surface. When coupled with a divert, the position estimate enables access to more challenging landing sites through pin-point landing or large hazard avoidance. The Lander Vision System (LVS) is a smart sensor system that performs terrain relative navigation by matching descent camera imagery to a map of the landing site and then fusing this with inertial measurements to obtain high rate map relative position, velocity and attitude estimates. A prototype of the LVS was recently tested in a helicopter field test over Mars analog terrain at altitudes representative of Mars Entry Descent and Landing conditions. TRN ran in real-time on the LVS during the flights without human intervention or tuning. The system was able to compute estimates accurate to 40m (3 sigma) in 10 seconds on a flight like processing system. This paper describes the Mars operational test space definition, how the field test was designed to cover that operational envelope, the resulting TRN performance across the envelope and an assessment of test space coverage.

Extraction of stability and control derivatives from orbiter flight data

NASA Technical Reports Server (NTRS)

Iliff, Kenneth W.; Shafer, Mary F.

1993-01-01

The Space Shuttle Orbiter has provided unique and important information on aircraft flight dynamics. This information has provided the opportunity to assess the flight-derived stability and control derivatives for maneuvering flight in the hypersonic regime. In the case of the Space Shuttle Orbiter, these derivatives are required to determine if certain configuration placards (limitations on the flight envelope) can be modified. These placards were determined on the basis of preflight predictions and the associated uncertainties. As flight-determined derivatives are obtained, the placards are reassessed, and some of them are removed or modified. Extraction of the stability and control derivatives was justified by operational considerations and not by research considerations. Using flight results to update the predicted database of the orbiter is one of the most completely documented processes for a flight vehicle. This process followed from the requirement for analysis of flight data for control system updates and for expansion of the operational flight envelope. These results show significant changes in many important stability and control derivatives from the preflight database. This paper presents some of the stability and control derivative results obtained from Space Shuttle flights. Some of the limitations of this information are also examined.

Origin, differentiation and functional ultrastructure of egg envelopes in the cestode Echinococcus multilocularis Leuckart, 1863 (Cyclophyllidea: Taeniidae).

PubMed

Świderski, Zdzisław; Miquel, Jordi; Azzouz-Maache, Samira; Pétavy, Anne-Françoise

2017-07-01

The origin, differentiation and functional ultrastructure of oncospheral or egg envelopes in Echinococcus multilocularis Leuckart, 1863 were studied by transmission electron microscopy (TEM) and cytochemistry. The purpose of our study is to describe the formation of the four primary embryonic envelopes, namely vitelline capsule, outer envelope, inner envelope and oncospheral membrane, and their transformation into the oncospheral or egg envelopes surrounding the mature hexacanth. This transformation takes place in the preoncospheral phase of embryonic development. The vitelline capsule and oncospheral membrane are thin membranes, while the outer and inner envelopes are thick cytoplasmic layers formed by two specific types of blastomeres: the outer envelope by cytoplasmic fusion of two macromeres and the inner envelope by cytoplasmic fusion of three mesomeres. Both outer and inner envelopes are therefore cellular in origin and syncytial in nature. During the advanced phase of embryonic development, the outer and inner envelopes undergo great modifications. The outer envelope remains as a metabolically active layer involved in the storage of glycogen and lipids for the final stages of egg development and survival. The inner envelope is the most important protective layer because of its thick layer of embryophoric blocks that assures oncospheral protection and survival. This embryophore is the principal layer of mature eggs, affording physical and physiological protection for the differentiated embryo or oncosphere, since the outer envelope is stripped from the egg before it is liberated. The embryophore is very thick and impermeable, consisting of polygonal blocks of an inert keratin-like protein held together by a cementing substance. The embryophore therefore assures extreme resistance of eggs, enabling them to withstand a wide range of environmental temperatures and physicochemical conditions.

Nonstationary envelope process and first excursion probability

NASA Technical Reports Server (NTRS)

Yang, J.

1972-01-01

A definition of the envelope of nonstationary random processes is proposed. The establishment of the envelope definition makes it possible to simulate the nonstationary random envelope directly. Envelope statistics, such as the density function, joint density function, moment function, and level crossing rate, which are relevent to analyses of catastrophic failure, fatigue, and crack propagation in structures, are derived. Applications of the envelope statistics to the prediction of structural reliability under random loadings are discussed in detail.

Multi-scale signed envelope inversion

NASA Astrophysics Data System (ADS)

Chen, Guo-Xin; Wu, Ru-Shan; Wang, Yu-Qing; Chen, Sheng-Chang

2018-06-01

Envelope inversion based on modulation signal mode was proposed to reconstruct large-scale structures of underground media. In order to solve the shortcomings of conventional envelope inversion, multi-scale envelope inversion was proposed using new envelope Fréchet derivative and multi-scale inversion strategy to invert strong contrast models. In multi-scale envelope inversion, amplitude demodulation was used to extract the low frequency information from envelope data. However, only to use amplitude demodulation method will cause the loss of wavefield polarity information, thus increasing the possibility of inversion to obtain multiple solutions. In this paper we proposed a new demodulation method which can contain both the amplitude and polarity information of the envelope data. Then we introduced this demodulation method into multi-scale envelope inversion, and proposed a new misfit functional: multi-scale signed envelope inversion. In the numerical tests, we applied the new inversion method to the salt layer model and SEG/EAGE 2-D Salt model using low-cut source (frequency components below 4 Hz were truncated). The results of numerical test demonstrated the effectiveness of this method.

Discharge lamp with reflective jacket

DOEpatents

MacLennan, Donald A.; Turner, Brian P.; Kipling, Kent

2001-01-01

A discharge lamp includes an envelope, a fill which emits light when excited disposed in the envelope, a source of excitation power coupled to the fill to excite the fill and cause the fill to emit light, and a reflector disposed around the envelope and defining an opening, the reflector being configured to reflect some of the light emitted by the fill back into the fill while allowing some light to exit through the opening. The reflector may be made from a material having a similar thermal index of expansion as compared to the envelope and which is closely spaced to the envelope. The envelope material may be quartz and the reflector material may be either silica or alumina. The reflector may be formed as a jacket having a rigid structure which does not adhere to the envelope. The lamp may further include an optical clement spaced from the envelope and configured to reflect an unwanted component of light which exited the envelope back into the envelope through the opening in the reflector. Light which can be beneficially recaptured includes selected wavelength regions, a selected polarization, and selected angular components.

Simulating a binary system that experiences the grazing envelope evolution

NASA Astrophysics Data System (ADS)

Shiber, Sagiv; Soker, Noam

2018-06-01

We conduct three-dimensional hydrodynamical simulations, and show that when a secondary star launches jets while performing spiral-in motion into the envelope of a giant star, the envelope is inflated, some mass is ejected by the jets, and the common envelope phase is postponed. We simulate this grazing envelope evolution (GEE) under the assumption that the secondary star accretes mass from the envelope of the asymptotic giant branch (AGB) star and launches jets. In these simulations we do not yet include the gravitational energy that is released by the spiraling-in binary system. Neither do we include the spinning of the envelope. Considering these omissions, we conclude that our results support the idea that jets might play a crucial role in the common envelope evolution or in preventing it.

Life Test Results for Water Heat Pipes Operating at 200 °C to 300 °C

NASA Astrophysics Data System (ADS)

Rosenfeld, John H.; Gernert, Nelson J.

2008-01-01

For lunar or planetary bases to be viable, a robust electric generating system will be required for powering the habitat. Water heat pipes offer an attractive solution for lunar base heat rejection, and would serve as a qualification for them on other long duration missions. Successful operation near the upper end of water operating range is a requirement for the application. Results are reported for life tests on water heat pipes that were operated at various temperatures between 200 °C and 300 °C. Tests were conducted on twenty three gravity-assisted water heat pipes. Eleven titanium/water heat pipes and ten Monel/water heat pipes were tested at temperatures above 200 °C. Two cupronickel heat pipes were also assembled and tested. Titanium alloys tested included CP-2 titanium, as well as two beta-titanium alloys, namely 15-3 and Nitinol alloys. Some of the titanium alloy life tests used wicks fabricated from CP-2 titanium screen or porous felt. Monel alloys tested included 400 and K-500 alloys. Some of the Monel heat pipes contained copper/nickel wicks that were fabricated by brazing nickel-plated copper felt metal wicks. Although most of the envelope/material combinations exhibit favorable results at 200 °C, some of the combinations failed at higher temperatures. Causes of failure included stress-creep of envelopes and corrosion at axial or end cap welds. This information represents a significant advance in selection of materials for 200 °C to 300 °C water heat pipes. Life testing work is being continued.

76 FR 47564 - Procurement List; Additions

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-05

...-117-9886--Envelope, Bubble Padded, 14\\1/2\\'' x 20''. NSN: 8105-00-290-0340--Envelope, Macerated Paper Padded, 6'' x 10''. NSN: 8105-00-290-0343--Envelope, Macerated Paper Padded, 8\\1/2\\'' x 12''. NSN: 8105-00-281-1168--Envelope, Macerated Paper Padded, 9\\1/2\\'' x 14\\1/2\\''. NSN: 8105-00-281-1436--Envelope...

2D magnetotelluric inversion using reflection seismic images as constraints and application in the COSC project

NASA Astrophysics Data System (ADS)

Kalscheuer, Thomas; Yan, Ping; Hedin, Peter; Garcia Juanatey, Maria d. l. A.

2017-04-01

We introduce a new constrained 2D magnetotelluric (MT) inversion scheme, in which the local weights of the regularization operator with smoothness constraints are based directly on the envelope attribute of a reflection seismic image. The weights resemble those of a previously published seismic modification of the minimum gradient support method introducing a global stabilization parameter. We measure the directional gradients of the seismic envelope to modify the horizontal and vertical smoothness constraints separately. An appropriate choice of the new stabilization parameter is based on a simple trial-and-error procedure. Our proposed constrained inversion scheme was easily implemented in an existing Gauss-Newton inversion package. From a theoretical perspective, we compare our new constrained inversion to similar constrained inversion methods, which are based on image theory and seismic attributes. Successful application of the proposed inversion scheme to the MT field data of the Collisional Orogeny in the Scandinavian Caledonides (COSC) project using constraints from the envelope attribute of the COSC reflection seismic profile (CSP) helped to reduce the uncertainty of the interpretation of the main décollement. Thus, the new model gave support to the proposed location of a future borehole COSC-2 which is supposed to penetrate the main décollement and the underlying Precambrian basement.

Optimal nonimaging integrated evacuated solar collector

NASA Astrophysics Data System (ADS)

Garrison, John D.; Duff, W. S.; O'Gallagher, Joseph J.; Winston, Roland

1993-11-01

A non imaging integrated evacuated solar collector for solar thermal energy collection is discussed which has the lower portion of the tubular glass vacuum enveloped shaped and inside surface mirrored to optimally concentrate sunlight onto an absorber tube in the vacuum. This design uses vacuum to eliminate heat loss from the absorber surface by conduction and convection of air, soda lime glass for the vacuum envelope material to lower cost, optimal non imaging concentration integrated with the glass vacuum envelope to lower cost and improve solar energy collection, and a selective absorber for the absorbing surface which has high absorptance and low emittance to lower heat loss by radiation and improve energy collection efficiency. This leads to a very low heat loss collector with high optical collection efficiency, which can operate at temperatures up to the order of 250 degree(s)C with good efficiency while being lower in cost than current evacuated solar collectors. Cost estimates are presented which indicate a cost for this solar collector system which can be competitive with the cost of fossil fuel heat energy sources when the collector system is produced in sufficient volume. Non imaging concentration, which reduces cost while improving performance, and which allows efficient solar energy collection without tracking the sun, is a key element in this solar collector design.

LPV Modeling of a Flexible Wing Aircraft Using Modal Alignment and Adaptive Gridding Methods

NASA Technical Reports Server (NTRS)

Al-Jiboory, Ali Khudhair; Zhu, Guoming; Swei, Sean Shan-Min; Su, Weihua; Nguyen, Nhan T.

2017-01-01

One of the earliest approaches in gain-scheduling control is the gridding based approach, in which a set of local linear time-invariant models are obtained at various gridded points corresponding to the varying parameters within the flight envelop. In order to ensure smooth and effective Linear Parameter-Varying control, aligning all the flexible modes within each local model and maintaining small number of representative local models over the gridded parameter space are crucial. In addition, since the flexible structural models tend to have large dimensions, a tractable model reduction process is necessary. In this paper, the notion of s-shifted H2- and H Infinity-norm are introduced and used as a metric to measure the model mismatch. A new modal alignment algorithm is developed which utilizes the defined metric for aligning all the local models over the entire gridded parameter space. Furthermore, an Adaptive Grid Step Size Determination algorithm is developed to minimize the number of local models required to represent the gridded parameter space. For model reduction, we propose to utilize the concept of Composite Modal Cost Analysis, through which the collective contribution of each flexible mode is computed and ranked. Therefore, a reduced-order model is constructed by retaining only those modes with significant contribution. The NASA Generic Transport Model operating at various flight speeds is studied for verification purpose, and the analysis and simulation results demonstrate the effectiveness of the proposed modeling approach.

Optimizing Aesthetic Outcomes in Delayed Breast Reconstruction

PubMed Central

2017-01-01

Background: The need to restore both the missing breast volume and breast surface area makes achieving excellent aesthetic outcomes in delayed breast reconstruction especially challenging. Autologous breast reconstruction can be used to achieve both goals. The aim of this study was to identify surgical maneuvers that can optimize aesthetic outcomes in delayed breast reconstruction. Methods: This is a retrospective review of operative and clinical records of all patients who underwent unilateral or bilateral delayed breast reconstruction with autologous tissue between April 2014 and January 2017. Three groups of delayed breast reconstruction patients were identified based on patient characteristics. Results: A total of 26 flaps were successfully performed in 17 patients. Key surgical maneuvers for achieving aesthetically optimal results were identified. A statistically significant difference for volume requirements was identified in cases where a delayed breast reconstruction and a contralateral immediate breast reconstruction were performed simultaneously. Conclusions: Optimal aesthetic results can be achieved with: (1) restoration of breast skin envelope with tissue expansion when possible, (2) optimal positioning of a small skin paddle to be later incorporated entirely into a nipple areola reconstruction when adequate breast skin surface area is present, (3) limiting the reconstructed breast mound to 2 skin tones when large area skin resurfacing is required, (4) increasing breast volume by deepithelializing, not discarding, the inferior mastectomy flap skin, (5) eccentric division of abdominal flaps when an immediate and delayed bilateral breast reconstructions are performed simultaneously; and (6) performing second-stage breast reconstruction revisions and fat grafting. PMID:28894666

Entire radial solutions of elliptic systems and inequalities of the mean curvature type

NASA Astrophysics Data System (ADS)

Filippucci, Roberta

2007-10-01

In this paper we study first nonexistence of radial entire solutions of elliptic systems of the mean curvature type with a singular or degenerate diffusion depending on the solution u. In particular we extend a previous result given in [R. Filippucci, Nonexistence of radial entire solutions of elliptic systems, J. Differential Equations 188 (2003) 353-389]. Moreover, in the scalar case we obtain nonexistence of all entire solutions, radial or not, of differential inequalities involving again operators of the mean curvature type and a diffusion term. We prove that in the scalar case, nonexistence of entire solutions is due to the explosion of the derivative of every nonglobal radial solution in the right extremum of the maximal interval of existence, while in that point the solution is bounded. This behavior is qualitatively different with respect to what happens for the m-Laplacian operator, studied in [R. Filippucci, Nonexistence of radial entire solutions of elliptic systems, J. Differential Equations 188 (2003) 353-389], where nonexistence of entire solutions is due, even in the vectorial case, to the explosion in norm of the solution at a finite point. Our nonexistence theorems for inequalities extend previous results given by Naito and Usami in [YE Naito, H. Usami, Entire solutions of the inequality div(A(=u)=u)[greater-or-equal, slanted]f(u), Math. Z. 225 (1997) 167-175] and Ghergu and Radulescu in [M. Ghergu, V. Radulescu, Existence and nonexistence of entire solutions to the logistic differential equation, Abstr. Appl. Anal. 17 (2003) 995-1003].

Envelope lipid-packing as a critical factor for the biological activity and stability of alphavirus particles isolated from mammalian and mosquito cells.

PubMed

Sousa, Ivanildo P; Carvalho, Carlos A M; Ferreira, Davis F; Weissmüller, Gilberto; Rocha, Gustavo M; Silva, Jerson L; Gomes, Andre M O

2011-01-21

Alphaviruses are enveloped arboviruses. The viral envelope is derived from the host cell and is positioned between two icosahedral protein shells (T = 4). Because the viral envelope contains glycoproteins involved in cell recognition and entry, the integrity of the envelope is critical for the success of the early events of infection. Differing levels of cholesterol in different hosts leads to the production of alphaviruses with distinct levels of this sterol loaded in the envelope. Using Mayaro virus, a New World alphavirus, we investigated the role of cholesterol on the envelope of alphavirus particles assembled in either mammalian or mosquito cells. Our results show that although quite different in their cholesterol content, Mayaro virus particles obtained from both cells share a similar high level of lateral organization in their envelopes. This organization, as well as viral stability and infectivity, is severely compromised when cholesterol is depleted from the envelope of virus particles isolated from mammalian cells, but virus particles isolated from mosquito cells are relatively unaffected by cholesterol depletion. We suggest that it is not cholesterol itself, but rather the organization of the viral envelope, that is critical for the biological activity of alphaviruses.

Energizing the last phase of common-envelope removal

NASA Astrophysics Data System (ADS)

Soker, Noam

2017-11-01

We propose a scenario where a companion that is about to exit a common-envelope evolution (CEE) with a giant star accretes mass from the remaining envelope outside its deep orbit and launches jets that facilitate the removal of the remaining envelope. The jets that the accretion disc launches collide with the envelope and form hot bubbles that energize the envelope. Due to gravitational interaction with the envelope, which might reside in a circumbinary disc, the companion migrates farther in, but the inner boundary of the circumbinary disc continues to feed the accretion disc. While near the equatorial plane mass leaves the system at a very low velocity, along the polar directions velocities are very high. When the primary is an asymptotic giant branch star, this type of flow forms a bipolar nebula with very narrow waists. We compare this envelope-removal process with four other last-phase common-envelope-removal processes. We also note that the accreted gas from the envelope outside the orbit in the last phase of the CEE might carry with it angular momentum that is anti-aligned to the orbital angular momentum. We discuss the implications to the possibly anti-aligned spins of the merging black hole event GW170104.

Comparison of Egg Envelope Thickness in Teleosts and its Relationship to the Sites of ZP Protein Synthesis.

PubMed

Sano, Kaori; Kawaguchi, Mari; Katano, Keita; Tomita, Kenji; Inokuchi, Mayu; Nagasawa, Tatsuki; Hiroi, Junya; Kaneko, Toyoji; Kitagawa, Takashi; Fujimoto, Takafumi; Arai, Katsutoshi; Tanaka, Masaru; Yasumasu, Shigeki

2017-05-01

Teleost egg envelope generally consists of a thin outer layer and a thick inner layer. The inner layer of the Pacific herring egg envelope is further divided into distinct inner layers I and II. In our previous study, we cloned four zona pellucida (ZP) proteins (HgZPBa, HgZPBb, HgZPCa, and HgZPCb) from Pacific herring, two of which (HgZPBa and HgZPCa) were synthesized in the liver and two (HgZPBb and HgZPCb) in the ovary. In this study, we raised antibodies against these four proteins to identify their locations using immunohistochemistry. Our results suggest that inner layer I is constructed primarily of HgZPBa and Ca, whereas inner layer II consists primarily of HgZPBa. HgZPBb and Cb were minor components of the envelope. Therefore, the egg envelope of Pacific herring is primarily composed of liver-synthesized ZP proteins. A comparison of the thickness of the fertilized egg envelopes of 55 species suggested that egg envelopes derived from liver-synthesized ZP proteins tended to be thicker in demersal eggs than those in pelagic eggs, whereas egg envelopes derived from ovarian-synthesized ZP proteins had no such tendency. Our comparison suggests that the prehatching period of an egg with a thick egg envelope is longer than that of an egg with a thin egg envelope. We hypothesized that acquisition of liver-synthesized ZP proteins during evolution conferred the ability to develop a thick egg envelope, which allowed species with demersal eggs to adapt to mechanical stress in the prehatching environment by thickening the egg envelope, while pelagic egg envelopes have remained thin. © 2017 Wiley Periodicals, Inc.

CCR5 Signal Transduction in Macrophages by Human Immunodeficiency Virus and Simian Immunodeficiency Virus Envelopes

PubMed Central

Arthos, James; Rubbert, Andrea; Rabin, Ronald L.; Cicala, Claudia; Machado, Elizabeth; Wildt, Kathryne; Hanbach, Meredith; Steenbeke, Tavis D.; Swofford, Ruth; Farber, Joshua M.; Fauci, Anthony S.

2000-01-01

The capacity of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) envelopes to transduce signals through chemokine coreceptors on macrophages was examined by measuring the ability of recombinant envelope proteins to mobilize intracellular calcium stores. Both HIV and SIV envelopes mobilized calcium via interactions with CCR5. The kinetics of these responses were similar to those observed when macrophages were treated with MIP-1β. Distinct differences in the capacity of envelopes to mediate calcium mobilization were observed. Envelopes derived from viruses capable of replicating in macrophages mobilized relatively high levels of calcium, while envelopes derived from viruses incapable of replicating in macrophages mobilized relatively low levels of calcium. The failure to efficiently mobilize calcium was not restricted to envelopes derived from CXCR4-utilizing isolates but also included envelopes derived from CCR5-utilizing isolates that fail to replicate in macrophages. We characterized one CCR5-utilizing isolate, 92MW959, which entered macrophages but failed to replicate. A recombinant envelope derived from this virus mobilized low levels of calcium. When macrophages were inoculated with 92MW959 in the presence of MIP-1α, viral replication was observed, indicating that a CC chemokine-mediated signal provided the necessary stimulus to allow the virus to complete its replication cycle. Although the role that envelope-CCR5 signal transduction plays in viral replication is not yet understood, it has been suggested that envelope-mediated signals facilitate early postfusion events in viral replication. The data presented here are consistent with this hypothesis and suggest that the differential capacity of viral envelopes to signal through CCR5 may influence their ability to replicate in macrophages. PMID:10864653

CCR5 signal transduction in macrophages by human immunodeficiency virus and simian immunodeficiency virus envelopes.

PubMed

Arthos, J; Rubbert, A; Rabin, R L; Cicala, C; Machado, E; Wildt, K; Hanbach, M; Steenbeke, T D; Swofford, R; Farber, J M; Fauci, A S

2000-07-01

The capacity of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) envelopes to transduce signals through chemokine coreceptors on macrophages was examined by measuring the ability of recombinant envelope proteins to mobilize intracellular calcium stores. Both HIV and SIV envelopes mobilized calcium via interactions with CCR5. The kinetics of these responses were similar to those observed when macrophages were treated with MIP-1beta. Distinct differences in the capacity of envelopes to mediate calcium mobilization were observed. Envelopes derived from viruses capable of replicating in macrophages mobilized relatively high levels of calcium, while envelopes derived from viruses incapable of replicating in macrophages mobilized relatively low levels of calcium. The failure to efficiently mobilize calcium was not restricted to envelopes derived from CXCR4-utilizing isolates but also included envelopes derived from CCR5-utilizing isolates that fail to replicate in macrophages. We characterized one CCR5-utilizing isolate, 92MW959, which entered macrophages but failed to replicate. A recombinant envelope derived from this virus mobilized low levels of calcium. When macrophages were inoculated with 92MW959 in the presence of MIP-1alpha, viral replication was observed, indicating that a CC chemokine-mediated signal provided the necessary stimulus to allow the virus to complete its replication cycle. Although the role that envelope-CCR5 signal transduction plays in viral replication is not yet understood, it has been suggested that envelope-mediated signals facilitate early postfusion events in viral replication. The data presented here are consistent with this hypothesis and suggest that the differential capacity of viral envelopes to signal through CCR5 may influence their ability to replicate in macrophages.

4H-SiC JFET Multilayer Integrated Circuit Technologies Tested Up to 1000 K

NASA Technical Reports Server (NTRS)

Spry, D. J.; Neudeck, P. G.; Chen, L.; Chang, C. W.; Lukco, D.; Beheim, G. M.

2015-01-01

Testing of semiconductor electronics at temperatures above their designed operating envelope is recognized as vital to qualification and lifetime prediction of circuits. This work describes the high temperature electrical testing of prototype 4H silicon carbide (SiC) junction field effect transistor (JFET) integrated circuits (ICs) technology implemented with multilayer interconnects; these ICs are intended for prolonged operation at temperatures up to 773K (500 C). A 50 mm diameter sapphire wafer was used in place of the standard NASA packaging for this experiment. Testing was carried out between 300K (27 C) and 1150K (877 C) with successful electrical operation of all devices observed up to 1000K (727 C).

Tentative civil airworthiness flight criteria for powered-lift transports

NASA Technical Reports Server (NTRS)

Hynes, C. S.; Scott, B. C.

1976-01-01

Representatives of the U.S., British, French, and Canadian airworthiness authorities participated in a NASA/FAA program to formulate tentative civil airworthiness flight criteria for powered-lift transports. The ultimate limits of the flight envelope are defined by boundaries in the airspeed/path-angle plane. Angle of attack and airspeed margins applied to these ultimate limits provide protection against both atmospheric disturbances and disturbances resulting from pilot actions or system variability, but do not ensure maneuvering capability directly, as the 30% speed margin does for conventional transports. Separate criteria provide for direct demonstration of adequate capability for approach path control, flare and landing, and for go-around. Demonstration maneuvers are proposed, and appropriate abuses and failures are suggested. Taken together, these criteria should permit selection of appropriate operating points within the flight envelopes for the approach, landing, and go-around flight phases which are likely to be most critical for powered-lift aircraft.

Scale, mergers and efficiency: the case of Dutch housing corporations.

PubMed

Veenstra, Jacob; Koolma, Hendrik M; Allers, Maarten A

2017-01-01

The efficiency of social housing providers is a contentious issue. In the Netherlands, there is a widespread belief that housing corporations have substantial potential for efficiency improvements. A related question is whether scale influences efficiency, since recent decades have shown a trend of mergers among corporations. This paper offers a framework to assess the effects of scale and mergers on the efficiency of Dutch housing corporations by using both a data envelopment analysis and a stochastic frontier analysis, using panel data for 2001-2012. The results indicate that most housing corporations operate under diseconomies of scale, implying that merging would be undesirable in most cases. However, merging may have beneficial effects on pure technical efficiency as it forces organizations to reconsider existing practices. A data envelopment analysis indeed confirms this hypothesis, but these results cannot be replicated by a stochastic frontier analysis, meaning that the evidence for this effect is not robust.

Advanced underwater lift device

NASA Technical Reports Server (NTRS)

Flanagan, David T.; Hopkins, Robert C.

1993-01-01

Flexible underwater lift devices ('lift bags') are used in underwater operations to provide buoyancy to submerged objects. Commercially available designs are heavy, bulky, and awkward to handle, and thus are limited in size and useful lifting capacity. An underwater lift device having less than 20 percent of the bulk and less than 10 percent of the weight of commercially available models was developed. The design features a dual membrane envelope, a nearly homogeneous envelope membrane stress distribution, and a minimum surface-to-volume ratio. A proof-of-concept model of 50 kg capacity was built and tested. Originally designed to provide buoyancy to mock-ups submerged in NASA's weightlessness simulators, the device may have application to water-landed spacecraft which must deploy flotation upon impact, and where launch weight and volume penalties are significant. The device may also be useful for the automated recovery of ocean floor probes or in marine salvage applications.

The Implications of Encoder/Modulator/ Phased Array Designs for Future Broadband LEO Communications

NASA Technical Reports Server (NTRS)

Vanderaar, Mark; Jensen, Chris A.; Terry, John D.

1997-01-01

In this paper we summarize the effects of modulation and channel coding on the design of wide angle scan, broadband, phased army antennas. In the paper we perform several trade studies. First, we investigate the amplifier back-off requirement as a function of variability of modulation envelope. Specifically, we contrast constant and non-constant envelope modulations, as well as single and multiple carrier schemes. Additionally, we address the issues an(f concerns of using pulse shaping filters with the above modulation types. Second, we quantify the effects of beam steering on the quality of data, recovery using selected modulation techniques. In particular, we show that the frequency response of the array introduces intersymbol interference for broadband signals and that the mode of operation for the beam steering controller may introduce additional burst or random errors. Finally, we show that the encoder/modulator design must be performed in conjunction with the phased array antenna design.

A stabilized optical frequency comb based on an Er-doped fiber femtosecond laser

NASA Astrophysics Data System (ADS)

Xia, Chuanqing; Wu, Tengfei; Zhao, Chunbo; Xing, Shuai

2018-03-01

An optical frequency comb based on a 250 MHz home-made Er-doped fiber femtosecond laser is presented in this paper. The Er-doped fiber laser has a ring cavity and operates mode-locked in femtosecond regime with the technique of nonlinear polarization rotation. The pulse duration is 118 fs and the spectral width is 30 nm. A part of the femtosecond laser is amplified in Er-doped fiber amplifier before propagating through a piece of highly nonlinear fiber for expanding the spectrum. The carrier-envelope offset frequency of the comb which has a signal-to-noise ratio more than 35 dB is extracted by means of f-2f beating. It demonstrates that both carrier-envelope offset frequency and repetition frequency keep phase locked to a Rubidium atomic clock simultaneously for 2 hours. The frequency stabilized fiber combs will be increasingly applied in optical metrology, attosecond pulse generation, and absolute distance measurement.

Methods for understanding super-efficient data envelopment analysis results with an application to hospital inpatient surgery.

PubMed

O'Neill, Liam; Dexter, Franklin

2005-11-01

We compare two techniques for increasing the transparency and face validity of Data Envelopment Analysis (DEA) results for managers at a single decision-making unit: multifactor efficiency (MFE) and non-radial super-efficiency (NRSE). Both methods incorporate the slack values from the super-efficient DEA model to provide a more robust performance measure than radial super-efficiency scores. MFE and NRSE are equivalent for unique optimal solutions and a single output. MFE incorporates the slack values from multiple output variables, whereas NRSE does not. MFE can be more transparent to managers since it involves no additional optimization steps beyond the DEA, whereas NRSE requires several. We compare results for operating room managers at an Iowa hospital evaluating its growth potential for multiple surgical specialties. In addition, we address the problem of upward bias of the slack values of the super-efficient DEA model.

Temperature feedback control for long-term carrier-envelope phase locking

DOEpatents

Chang, Zenghu [Manhattan, KS; Yun, Chenxia [Manhattan, KS; Chen, Shouyuan [Manhattan, KS; Wang, He [Manhattan, KS; Chini, Michael [Manhattan, KS

2012-07-24

A feedback control module for stabilizing a carrier-envelope phase of an output of a laser oscillator system comprises a first photodetector, a second photodetector, a phase stabilizer, an optical modulator, and a thermal control element. The first photodetector may generate a first feedback signal corresponding to a first portion of a laser beam from an oscillator. The second photodetector may generate a second feedback signal corresponding to a second portion of the laser beam filtered by a low-pass filter. The phase stabilizer may divide the frequency of the first feedback signal by a factor and generate an error signal corresponding to the difference between the frequency-divided first feedback signal and the second feedback signal. The optical modulator may modulate the laser beam within the oscillator corresponding to the error signal. The thermal control unit may change the temperature of the oscillator corresponding to a signal operable to control the optical modulator.

Flight evaluation results for a digital electronic engine control in an F-15 airplane

NASA Technical Reports Server (NTRS)

Burcham, F. W., Jr.; Myers, L. P.; Walsh, K. R.

1983-01-01

A digital electronic engine control (DEEC) system on an F100 engine in an F-15 airplane was evaluated in flight. Thirty flights were flown in a four-phase program from June 1981 to February 1983. Significant improvements in the operability and performance of the F100 engine were developed as a result of the flight evaluation: the augmentor envelope was increased by 15,000 ft, the airstart envelope was improved by 75 knots, and the need to periodically trim the engine was eliminated. The hydromechanical backup control performance was evaluated and was found to be satisfactory. Two system failures were encountered in the test program; both were detected and accommodated successfully. No transfers to the backup control system were required, and no automatic transfers occurred. As a result of the successful DEEC flight evaluation, the DEEC system has entered the full-scale development phase.

Advanced high pressure engine study for mixed-mode vehicle applications

NASA Technical Reports Server (NTRS)

Luscher, W. P.; Mellish, J. A.

1977-01-01

High pressure liquid rocket engine design, performance, weight, envelope, and operational characteristics were evaluated for a variety of candidate engines for use in mixed-mode, single-stage-to-orbit applications. Propellant property and performance data were obtained for candidate Mode 1 fuels which included: RP-1, RJ-5, hydrazine, monomethyl-hydrazine, and methane. The common oxidizer was liquid oxygen. Oxygen, the candidate Mode 1 fuels, and hydrogen were evaluated as thrust chamber coolants. Oxygen, methane, and hydrogen were found to be the most viable cooling candidates. Water, lithium, and sodium-potassium were also evaluated as auxiliary coolant systems. Water proved to be the best of these, but the system was heavier than those systems which cooled with the engine propellants. Engine weight and envelope parametric data were established for candidate Mode 1, Mode 2, and dual-fuel engines. Delivered engine performance data were also calculated for all candidate Mode 1 and dual-fuel engines.

Probability of loss of assured safety in systems with multiple time-dependent failure modes.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Helton, Jon Craig; Pilch, Martin.; Sallaberry, Cedric Jean-Marie.

2012-09-01

Weak link (WL)/strong link (SL) systems are important parts of the overall operational design of high-consequence systems. In such designs, the SL system is very robust and is intended to permit operation of the entire system under, and only under, intended conditions. In contrast, the WL system is intended to fail in a predictable and irreversible manner under accident conditions and render the entire system inoperable before an accidental operation of the SL system. The likelihood that the WL system will fail to deactivate the entire system before the SL system fails (i.e., degrades into a configuration that could allowmore » an accidental operation of the entire system) is referred to as probability of loss of assured safety (PLOAS). Representations for PLOAS for situations in which both link physical properties and link failure properties are time-dependent are derived and numerically evaluated for a variety of WL/SL configurations, including PLOAS defined by (i) failure of all SLs before failure of any WL, (ii) failure of any SL before failure of any WL, (iii) failure of all SLs before failure of all WLs, and (iv) failure of any SL before failure of all WLs. The effects of aleatory uncertainty and epistemic uncertainty in the definition and numerical evaluation of PLOAS are considered.« less

Envelopes in eclipsing binary stars

NASA Technical Reports Server (NTRS)

Huang, S.

1972-01-01

Theoretical research on eclipsing binaries is presented. The specific areas of investigation are the following: (1) the relevance of envelopes to the study of the light curves of eclipsing binaries, (2) the disk envelope, and (3) the spherical envelope.

Nonlinear Wave Propagation

DTIC Science & Technology

2009-02-12

describes the mode- locking and dynamics of solitons . A characteristic of short pulse lasers is the carrier-envelope phase (CEP) slip which is the change in...and evolution of pulses in mode- locked lasers that are operating in the soliton regime. To describe our research in more detail, we fix typical...solutions with mode- locking evolution. Otherwise the solitons are found to be unstable; either dispersing to radiation or evolving into nonlocalized

FY2016 Update on ILAW Glass Testing for Disposal at IDF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, E. E.; Swanberg, D. J.; Muller, Isabelle S.

2017-04-12

This status report provides a FY2016 update on work performed to collect information on the corrosion behavior of LAW glasses to support the IDF PA. In addition to the development of the baseline operating envelope for the WTP, since 2003, VSL has developed a wide range of LAW formulations that achieve considerably higher waste loadings than the WTP baseline formulations.

Natural vacuum electronics

NASA Technical Reports Server (NTRS)

Leggett, Nickolaus

1990-01-01

The ambient natural vacuum of space is proposed as a basis for electron valves. Each valve is an electron controlling structure similiar to a vacuum tube that is operated without a vacuum sustaining envelope. The natural vacuum electron valves discussed offer a viable substitute for solid state devices. The natural vacuum valve is highly resistant to ionizing radiation, system generated electromagnetic pulse, current transients, and direct exposure to space conditions.

Company Level Logistics on the Future Battlefield.

DTIC Science & Technology

1993-12-17

also expands the terrain envelope in which responsive logistics can be provided. Self diagnostic equipment is currently imbedded in many of our new ...satellite systems, improved sensors, better communications, and long range weapons systems. The combined effect of these systems creates a new ...battlefield. To support combat operations in light of these changes, logistics units must adapt to the new environment. In the past American logistics units

Inlet Distortion Generation for a Transonic Compressor

DTIC Science & Technology

2004-09-01

9 Figure 6. Compressor pumping characteristic measured at 90% design speed and degradation assumed for distortion design ...INTENTIONALLY LEFT BLANK 1 I. INTRODUCTION Engines for military fighter aircraft must be designed to operate stably over a required flight envelope. An...adequate “stall margin” is usually an engine design requirement. Since distortion of the flow into the fan or compressor is known to reduce the

Development of models simulating operation of elements of radio devices, for solving problems of ensuring electromagnetic compatibility of radio electronic means

NASA Astrophysics Data System (ADS)

Glotov, V. V.; Ostroumov, I. V.; Romashchenko, M. A.

2018-05-01

To study the effect of phase-shift signals parameters on EMC of REM, a generalized signal generation model in a radio transmitter was developed which allows obtaining digital representations of phase-shift signals, which are a continuous pulse in the time domain and on the frequency axis with different signal element envelope shapes.

Measuring Academic Library Efficiency and Alignment with Institutional Resource Utilization Priorities Using Data Envelopment Analysis: An Analysis of Institutions of Higher Education in Texas and Their Libraries

ERIC Educational Resources Information Center

Shupala, Christine M.

2012-01-01

Academic and library administrators are increasingly required to demonstrate efficiency in programs, services, and operations as well as effectiveness. An important component of efficiency measurement is identification of a relevant peer group against which to compare the administrative unit to determine relative efficiency. The two-fold purpose…

Comparison of closed and open methods of pneumoperitonium in laparoscopic cholecystectomy.

PubMed

Akbar, Mohammad; Khan, Ishtiaq Ali; Naveed, Danish; Khattak, Irfanuddin; Zafar, Arshad; Wazir, Muhammad Salim; Khan, Asif Nawaz; Zia-ur-Rehman

2008-01-01

Pneumoperitonium is the first step in laparoscopic surgery including cholecystectomy. Two commonly used methods to create pneumoperitonium are closed and open technique. Both have advantages and disadvantages. The current study was designed to compare these two techniques in terms of safety and time required to complete the procedure. This was a randomized controlled prospective study conducted at Department of Surgery, Ayub Hospital Complex Abbottabad, from 1st June 2007 to 31st May 2008. Randomization was done into two groups randomly using sealed envelopes containing the questionnaire. Seventy envelopes were kept in the cupboard, containing 35 proformas for group A and 35 for group B. An envelope was randomly fetched and opened upon selection of the patient after taking the informed consent. Pneumoperitonium was created by closed technique in group A, and by open technique in group B. Time required for successful pneumoperitonium was calculated in each group. Failure to induce pneumoperitonium was determined for each technique. Time required to close the wounds at completion, total operating time and injuries sustained during induction of pneumoperitonium were compared in both techniques. Out of the total 70 patients included in study, 35 were in group A and 35 in group B. Mean time required for successful pneumoperitonium was 9.17 minutes in group A and 8.11 minutes in group B. Total operating time ranged from 55 minutes to 130 minutes in group A and from 45 minutes to 110 minutes in group B. Mean of total operating time was 78.34 and 67 minutes in group A and B respectively. Mean time needed to close the wound was 9.88 minutes in group A and 4.97 minutes in group B. Failure of technique was noted in three patients in group A while no failure was experienced in group B. In two cases in group A minor complications during creation of pneumoperitonium were observed while in group B no complication occurred. No patient died in the study. We concluded from this study that open technique of pneumoperitonium was, less time consuming and safer than the closed technique.

Abatement of PAPR for ACO-OFDM deployed in VLC systems by frequency modulation of the baseband signal forming a constant envelope

NASA Astrophysics Data System (ADS)

Kumar Singh, Vinay; Dalal, U. D.

2017-06-01

To inhibit the effect of non-linearity of the LEDs leading to a significant increase in the peak to average power ratio (PAPR) of the OFDM signals in the Visible light communication (VLC) we propose a frequency modulated constant envelope OFDM (FM CE-OFDM) technique. The abrupt amplitude variations in the OFDM signal are frequency modulated before being applied to the LED for electro-optical conversion resulting in a constant envelope signal. The LED is maintained in the linear region of operation by this constant envelope signal at sufficient DC bias. The proposed technique reduces the PAPR to the least possible value ≈0 dB. We theoretically analyze and perform numerical simulations to assess the enhancement of the proposed system. The optimal modulation index is found to be 0.3. The metrics pertaining to the evaluation of the phase discontinuity is derived and is found to be lesser for the FM CE-OFDM as compared to the phase modulated (PM) CE-OFDM. The receiver sensitivity is improved by 1.6 dB for a transmission distance of 2 m for the FM CE-OFDM as compared to the PM CE-OFDM at the FEC threshold. We compare the BER performance of the ideal OFDM (without the non linearity of LED), power back-off OFDM, PM CE-OFDM and FM CE-OFDM in an optical wireless channel (OWC) scenario. The FM CE-OFDM has an improvement of 2.1 dB SNR at the FEC threshold as compared to the PM CE-OFDM. It also shows an improvement of 11 dB when compared with the power back-off technique used in the VLC systems for 10 dB power back-off.

Three-dimensional simulations of turbulent convective mixing in ONe and CO classical nova explosions

DOE PAGES

Casanova, Jordi; José, Jordi; García-Berro, Enrique; ...

2016-10-25

Classical novae are thermonuclear explosions that take place in the envelopes of accreting white dwarfs in binary systems. The material piles up under degenerate conditions, driving a thermonuclear runaway. The energy released by the suite of nuclear processes operating at the envelope heats the material up to peak temperatures of ~(1-4) × 10 8 K. During these events, about 10 -3-10 -7 M ⊙, enriched in CNO and, sometimes, other intermediate-mass elements (e.g., Ne, Na, Mg, Al) are ejected into the interstellar medium. To account for the gross observational properties of classical novae (in particular, the high concentrations of metalsmore » spectroscopically inferred in the ejecta), models require mixing between the (solar-like) material transferred from the secondary and the outermost layers (CO- or ONe-rich) of the underlying white dwarf. Recent multidimensional simulations have demonstrated that Kelvin-Helmholtz instabilities can naturally produce self-enrichment of the accreted envelope with material from the underlying white dwarf at levels that agree with observations. However, the feasibility of this mechanism has been explored in the framework of CO white dwarfs, while mixing with different substrates still needs to be properly addressed. We performed three-dimensional simulations of mixing at the core-envelope interface during nova outbursts with the multidimensional code FLASH, for two types of substrates: CO- and ONe-rich. We also show that the presence of an ONe-rich substrate, as in “neon novae”, yields higher metallicity enhancements in the ejecta than CO-rich substrates (i.e., non-neon novae). Finally, a number of requirements and constraints for such 3D simulations (e.g., minimum resolution, size of the computational domain) are also outlined.« less

Effects of lesions of the dorsal noradrenergic bundle on conditioned suppression to a CS and to a contextual background stimulus.

PubMed

Tsaltas, E; Schugens, M M; Gray, J A

1989-01-01

The aim of the experiment was to determine whether the dorsal noradrenergic bundle (DB) plays a role in conditioning to context. Rats received either bilateral lesions of the DB by local injection of 6-hydroxydopamine, vehicle injections only, or sham operations. All animals were then trained to barpress for food on a variable interval (VI) schedule. Two 5-min intrusion periods were superimposed on the VI baseline during each session. An 'envelope' stimulus (flashing light) was on throughout each intrusion period. In addition, embedded in the two intrusion periods of each session, there occurred 8 presentations of a 'punctate' conditioned stimulus (CS) (a 15-s clicker), and 8 presentations of a 0.5-s footshock. Within each surgical condition rats were randomly allocated to one of three conditioning groups, receiving 100%, 50% or 0% temporal association between CS and shock. Conditioning to the punctate CS and to the context provided by the envelope stimulus was assessed by the degree of suppression of the barpress response relative to the VI baseline. Responding was most suppressed in the punctate CS in the 100 and 50% conditions, and most suppressed in the envelope stimulus in the 0% condition. DB lesions released response suppression to the punctate CS, had no effect on suppression to the envelope stimulus, and reduced sensitivity to CS-shock probability as measured by response suppression during the punctate CS. These results confirm previous reports that DB lesions alleviate response suppression to shock-associated cues, identify some of the parameters that affect this phenomenon, but fail to support a role for the DB in contextual conditioning.

Studies on the System Regulating Proton Movement across the Chloroplast Envelope 1

PubMed Central

Peters, Jeanne S.; Berkowitz, Gerald A.

1991-01-01

Studies were undertaken to further characterize the spinach (Spinacea oleracea) chloroplast envelope system, which facilitates H+ movement into and out of the stroma, and, hence, modulates photosynthetic activity by regulating stromal pH. It was demonstrated that high envelope-bound Mg2+ causes stromal acidification and photosynthetic inhibition. High envelope-bound Mg2+ was also found to necessitate the activity of a digitoxinand oligomycin-sensitive ATPase for the maintenance of high stromal pH and photosynthesis in the illuminated chloroplast. In chloroplasts that had high envelope Mg2+ and inhibited envelope ATPase activity, 2-(diethylamino)-N-(2,6-dimethylphenyl)acetamide was found to raise stromal pH and stimulate photosynthesis. 2-(Diethylamino)-N-(2,6-dimethylphenyl)acetamide is an amine anesthetic that is known to act as a monovalent cation channel blocker in mammalian systems. We postulate that the system regulating cation and H+ fluxes across the plastid envelope includes a monovalent cation channel in the envelope, some degree of (envelope-bound Mg2+ modulated) H+ flux linked to monovalent cation antiport, and ATPase-dependent H+ efflux. PMID:16668116

Safe operating conditions for NSLS-II Storage Ring Frontends commissioning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seletskiy, S.; Amundsen, C.; Ha, K.

2015-04-02

The NSLS-II Storage Ring Frontends are designed to safely accept the synchrotron radiation fan produced by respective insertion device when the electron beam orbit through the ID is locked inside the predefined Active Interlock Envelope. The Active Interlock is getting enabled at a particular beam current known as AI safe current limit. Below such current the beam orbit can be anywhere within the limits of the SR beam acceptance. During the FE commissioning the beam orbit is getting intentionally disturbed in the particular ID. In this paper we explore safe operating conditions for the Frontends commissioning.

Human Factors Vehicle Displacement Analysis: Engineering In Motion

NASA Technical Reports Server (NTRS)

Atencio, Laura Ashley; Reynolds, David; Robertson, Clay

2010-01-01

While positioned on the launch pad at the Kennedy Space Center, tall stacked launch vehicles are exposed to the natural environment. Varying directional winds and vortex shedding causes the vehicle to sway in an oscillating motion. The Human Factors team recognizes that vehicle sway may hinder ground crew operation, impact the ground system designs, and ultimately affect launch availability . The objective of this study is to physically simulate predicted oscillation envelopes identified by analysis. and conduct a Human Factors Analysis to assess the ability to carry out essential Upper Stage (US) ground operator tasks based on predicted vehicle motion.

The test of VLSI circuits

NASA Astrophysics Data System (ADS)

Baviere, Ph.

Tests which have proven effective for evaluating VLSI circuits for space applications are described. It is recommended that circuits be examined after each manfacturing step to gain fast feedback on inadequacies in the production system. Data from failure modes which occur during operational lifetimes of circuits also permit redefinition of the manufacturing and quality control process to eliminate the defects identified. Other tests include determination of the operational envelope of the circuits, examination of the circuit response to controlled inputs, and the performance and functional speeds of ROM and RAM memories. Finally, it is desirable that all new circuits be designed with testing in mind.

Carrier-envelope phase dynamics and noise analysis in octave-spanning Ti:sapphire lasers.

PubMed

Matos, Lia; Mücke, Oliver D; Chen, Jian; Kärtner, Franz X

2006-03-20

We investigate the carrier-envelope phase dynamics of octave-spanning Ti:sapphire lasers and perform a complete noise analysis of the carrier-envelope phase stabilization. We model the effect of the laser dynamics on the residual carrier-envelope phase noise by deriving a transfer function representation of the octave-spanning frequency comb. The modelled phase noise and the experimental results show excellent agreement. This greatly enhances our capability of predicting the dependence of the residual carrier-envelope phase noise on the feedback loop filter, the carrier-envelope frequency control mechanism and the pump laser used.

Identification of an Envelope Protein from the FRD Family of Human Endogenous Retroviruses (HERV-FRD) Conferring Infectivity and Functional Conservation among Simians

PubMed Central

Blaise, Sandra; Ruggieri, Alessia; Dewannieux, Marie; Cosset, François-Loic; Heidmann, Thierry

2004-01-01

A member of the HERV-W family of human endogenous retroviruses (HERV) had previously been demonstrated to encode a functional envelope which can form pseudotypes with human immunodeficiency virus type 1 virions and confer infectivity on the resulting retrovirus particles. Here we show that a second envelope protein sorted out by a systematic search for fusogenic proteins that we made among all the HERV coding envelope genes and belonging to the HERV-FRD family can also make pseudotypes and confer infectivity. We further show that the orthologous envelope genes that were isolated from simians—from New World monkeys to humans—are also functional in the infectivity assay, with one singular exception for the gibbon HERV-FRD gene, which is found to be fusogenic in a cell-cell fusion assay, as observed for the other simian envelopes, but which is not infectious. Sequence comparison of the FRD envelopes revealed a limited number of mutations among simians, and one point mutation—located in the TM subunit—was shown to be responsible for the loss of infectivity of the gibbon envelope. The functional characterization of the identified envelopes is strongly indicative of an ancestral retrovirus infection and endogenization, with some of the envelope functions subsequently retained in evolution. PMID:14694139

Identification of an envelope protein from the FRD family of human endogenous retroviruses (HERV-FRD) conferring infectivity and functional conservation among simians.

PubMed

Blaise, Sandra; Ruggieri, Alessia; Dewannieux, Marie; Cosset, François-Loic; Heidmann, Thierry

2004-01-01

A member of the HERV-W family of human endogenous retroviruses (HERV) had previously been demonstrated to encode a functional envelope which can form pseudotypes with human immunodeficiency virus type 1 virions and confer infectivity on the resulting retrovirus particles. Here we show that a second envelope protein sorted out by a systematic search for fusogenic proteins that we made among all the HERV coding envelope genes and belonging to the HERV-FRD family can also make pseudotypes and confer infectivity. We further show that the orthologous envelope genes that were isolated from simians-from New World monkeys to humans-are also functional in the infectivity assay, with one singular exception for the gibbon HERV-FRD gene, which is found to be fusogenic in a cell-cell fusion assay, as observed for the other simian envelopes, but which is not infectious. Sequence comparison of the FRD envelopes revealed a limited number of mutations among simians, and one point mutation-located in the TM subunit-was shown to be responsible for the loss of infectivity of the gibbon envelope. The functional characterization of the identified envelopes is strongly indicative of an ancestral retrovirus infection and endogenization, with some of the envelope functions subsequently retained in evolution.

Estimation of fan pressure ratio requirements and operating performance for the National Transonic Facility

NASA Technical Reports Server (NTRS)

Gloss, B. B.; Nystrom, D.

1981-01-01

The National Transonic Facility (NTF), a fan-driven, transonic, pressurized, cryogenic wind tunnel, will operate over the Mach number range of 0.10 to 1.20 with stagnation pressures varying from 1.00 to about 8.8 atm and stagnation temperatures varying from 77 to 340 K. The NTF is cooled to cryogenic temperatures by the injection of liquid nitrogen into the tunnel stream with gaseous nitrogen as the test gas. The NTF can also operate at ambient temperatures using a conventional chilled water heat exchanger with air on nitrogen as the test gas. The methods used in estimating the fan pressure ratio requirements are described. The estimated NTF operating envelopes at Mach numbers from 0.10 to 1.20 are presented.

On-Line Safe Flight Envelope Determination for Impaired Aircraft

NASA Technical Reports Server (NTRS)

Lombaerts, Thomas; Schuet, Stefan; Acosta, Diana; Kaneshige, John

2015-01-01

The design and simulation of an on-line algorithm which estimates the safe maneuvering envelope of aircraft is discussed in this paper. The trim envelope is estimated using probabilistic methods and efficient high-fidelity model based computations of attainable equilibrium sets. From this trim envelope, a robust reachability analysis provides the maneuverability limitations of the aircraft through an optimal control formulation. Both envelope limits are presented to the flight crew on the primary flight display. In the results section, scenarios are considered where this adaptive algorithm is capable of computing online changes to the maneuvering envelope due to impairment. Furthermore, corresponding updates to display features on the primary flight display are provided to potentially inform the flight crew of safety critical envelope alterations caused by the impairment.

Stationary light pulse in solids with long-lived spin coherence

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang Xiaojun; Wang Haihua; Wang Lei

We present a detailed analysis of stationary light pulses (SLP's) for the case of inhomogeneous broadening in both optical and spin transitions, which is normally found in solid materials with long-lived spin coherence. By solving the Langevin equations of motion for the density matrix elements under the integral over the entire range of the inhomogeneous broadenings, the necessary conditions for creating the SLP in a solid are obtained. Then the decay and diffusion processes that the SLP undergoes are analyzed. The characteristics of such processes are studied based on the analytic solution of the SLP with a slowly varying envelope.more » The dependence of SLP lifetime on inhomogeneous broadenings of spin and optical transitions, which can be regarded as the laser linewidth in the repump scheme, has been discussed.« less

Coreceptor use in nonhuman primate models of HIV infection.

PubMed

Sina, Silvana Tasca; Ren, Wuze; Cheng-Mayer, Cecilia

2011-01-27

SIV or SHIV infection of nonhuman primates (NHP) has been used to investigate the impact of coreceptor usage on the composition and dynamics of the CD4+ T cell compartment, mechanisms of disease induction and development of clinical syndrome. As the entire course of infection can be followed, with frequent access to tissue compartments, infection of rhesus macaques with CCR5-tropic SHIVs further allows for study of HIV-1 coreceptor switch after intravenous and mucosal inoculation, with longitudinal and systemic analysis to determine the timing, anatomical sites and cause for the change in envelope glycoprotein and coreceptor preference. Here, we review our current understanding of coreceptor use in NHPs and their impact on the pathobiological characteristics of the infection, and discuss recent advances in NHP studies to uncover the underlying selective pressures for the change in coreceptor preference in vivo.

Robust Gain-Scheduled Fault Tolerant Control for a Transport Aircraft

NASA Technical Reports Server (NTRS)

Shin, Jong-Yeob; Gregory, Irene

2007-01-01

This paper presents an application of robust gain-scheduled control concepts using a linear parameter-varying (LPV) control synthesis method to design fault tolerant controllers for a civil transport aircraft. To apply the robust LPV control synthesis method, the nonlinear dynamics must be represented by an LPV model, which is developed using the function substitution method over the entire flight envelope. The developed LPV model associated with the aerodynamic coefficient uncertainties represents nonlinear dynamics including those outside the equilibrium manifold. Passive and active fault tolerant controllers (FTC) are designed for the longitudinal dynamics of the Boeing 747-100/200 aircraft in the presence of elevator failure. Both FTC laws are evaluated in the full nonlinear aircraft simulation in the presence of the elevator fault and the results are compared to show pros and cons of each control law.

Infection control in digital intraoral radiography: evaluation of microbiological contamination of photostimulable phosphor plates in barrier envelopes.

PubMed

MacDonald, David S; Waterfield, J Douglas

2011-01-01

The detectors (both solid-state sensors and photostimulable phosphor [PSP] plates) used for digital intraoral radiography cannot be autoclaved, and barriers are typically used to prevent the spread of infection. The aim of this study was to determine the effectiveness of a barrier envelope system for PSP plates. Disinfected PSP plates were aseptically inserted into barrier envelopes and placed in a periapical location. One PSP plate was placed in each of 28 patients, and 12 plates in each of 2 volunteers (D.S.M., J.D.W.). After retrieval, each PSP plate was removed from its barrier envelope, immersed in trypticase soy broth and aliquots were plated on trypticase soy agar. Bacterial colonies were counted 2 days later. Fifty-two PSP plates in barrier envelopes were evaluated for contamination. Quality assurance of the PSP plates before clinical placement revealed defects in the integrity of 4 barrier envelopes, caused by forceps-related damage or failure to achieve a uniform seal. These defects allowed substantial contamination. Contamination also occurred as a result of failure to extract the PSP plate from the barrier envelope cleanly. Of the 44 barriers with no obvious defects that were placed by either final-year dental students or a radiologist, only 3 allowed bacterial contamination of the PSP plate. Detectors contained in barrier envelopes remain a potential source of contamination. PSP plates must be disinfected between removal from a contaminated barrier envelope and placement in a new barrier envelope. In addition, placement into the barrier envelope should ideally be carried out under aseptic conditions. Finally, the integrity of each sealed barrier envelope must be verified visually before release to the clinic.

A baculovirus polyhedron envelope protein: immunogold localization in infected cells and mature polyhedra.

PubMed

Russell, R L; Rohrmann, G F

1990-01-01

A polyclonal antiserum against a trpE fusion protein containing the complete open reading frame of the polyhedron envelope (PE) protein from the nuclear polyhedrosis virus of Orgyia pseudotsugata (OpMNPV) was used for immunogold staining and electron microscopic examination of polyhedra, isolated polyhedron envelopes, and infected insect cells at selected times postinfection. The antiserum specifically stained the peripheral envelope of mature polyhedra and also stained the envelope structure which remained after polyhedra were dissolved in dilute alkaline solutions. In OpMNPV-infected Lymantria dispar cells, the PE protein was detected by 48 hr postinfection (hr p.i.) but specific localization and staining of developing polyhedra were not evident. However, by 72 hr p.i. substantial and preferential staining of the periphery of developing polyhedra was evident even though a distinct polyhedron envelope was not yet observed. In addition, the periphery of fibrillar structures was stained by the PE antiserum. By 96 hr p.i., mature envelopes surrounded polyhedra and these polyhedron envelopes were stained with the PE antibody. The progression of PE protein staining during polyhedron morphogenesis indicates that the PE protein accumulates and becomes associated with developing polyhedra in the nucleus between 48 and 72 hr p.i. Very late in infection the mature polyhedron envelope forms on the polyhedron surface. The apparent affinity of the PE protein for the surface of maturing polyhedra suggests that it may be a major component of the polyhedron envelope or may form the matrix for the deposition of other components which contribute to the mature envelope. Immunogold staining and protease digestion experiments indicate that protein is an essential component of the polyhedron envelope.

Conservation of the egg envelope digestion mechanism of hatching enzyme in euteleostean fishes.

PubMed

Kawaguchi, Mari; Yasumasu, Shigeki; Shimizu, Akio; Sano, Kaori; Iuchi, Ichiro; Nishida, Mutsumi

2010-12-01

We purified two hatching enzymes, namely high choriolytic enzyme (HCE; EC 3.4.24.67) and low choriolytic enzyme (LCE; EC 3.4.24.66), from the hatching liquid of Fundulus heteroclitus, which were named Fundulus HCE (FHCE) and Fundulus LCE (FLCE). FHCE swelled the inner layer of egg envelope, and FLCE completely digested the FHCE-swollen envelope. In addition, we cloned three Fundulus cDNAs orthologous to cDNAs for the medaka precursors of egg envelope subunit proteins (i.e. choriogenins H, H minor and L) from the female liver. Cleavage sites of FHCE and FLCE on egg envelope subunit proteins were determined by comparing the N-terminal amino acid sequences of digests with the sequences deduced from the cDNAs for egg envelope subunit proteins. FHCE and FLCE cleaved different sites of the subunit proteins. FHCE efficiently cleaved the Pro-X-Y repeat regions into tripeptides to dodecapeptides to swell the envelope, whereas FLCE cleaved the inside of the zona pellucida domain, the core structure of egg envelope subunit protein, to completely digest the FHCE-swollen envelope. A comparison showed that the positions of hatching enzyme cleavage sites on egg envelope subunit proteins were strictly conserved between Fundulus and medaka. Finally, we extended such a comparison to three other euteleosts (i.e. three-spined stickleback, spotted halibut and rainbow trout) and found that the egg envelope digestion mechanism was well conserved among them. During evolution, the egg envelope digestion by HCE and LCE orthologs was established in the lineage of euteleosts, and the mechanism is suggested to be conserved. © 2010 The Authors Journal compilation © 2010 FEBS.

40 CFR 426.120 - Applicability; description of the incandescent lamp envelope manufacturing subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... incandescent lamp envelope manufacturing subcategory. 426.120 Section 426.120 Protection of Environment... POINT SOURCE CATEGORY Incandescent Lamp Envelope Manufacturing Subcategory § 426.120 Applicability; description of the incandescent lamp envelope manufacturing subcategory. The provisions of this subpart are...

40 CFR 426.120 - Applicability; description of the incandescent lamp envelope manufacturing subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... incandescent lamp envelope manufacturing subcategory. 426.120 Section 426.120 Protection of Environment... POINT SOURCE CATEGORY Incandescent Lamp Envelope Manufacturing Subcategory § 426.120 Applicability; description of the incandescent lamp envelope manufacturing subcategory. The provisions of this subpart are...

40 CFR 426.120 - Applicability; description of the incandescent lamp envelope manufacturing subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... incandescent lamp envelope manufacturing subcategory. 426.120 Section 426.120 Protection of Environment... POINT SOURCE CATEGORY Incandescent Lamp Envelope Manufacturing Subcategory § 426.120 Applicability; description of the incandescent lamp envelope manufacturing subcategory. The provisions of this subpart are...

40 CFR 426.120 - Applicability; description of the incandescent lamp envelope manufacturing subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... incandescent lamp envelope manufacturing subcategory. 426.120 Section 426.120 Protection of Environment... CATEGORY Incandescent Lamp Envelope Manufacturing Subcategory § 426.120 Applicability; description of the incandescent lamp envelope manufacturing subcategory. The provisions of this subpart are applicable to...

40 CFR 426.120 - Applicability; description of the incandescent lamp envelope manufacturing subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... incandescent lamp envelope manufacturing subcategory. 426.120 Section 426.120 Protection of Environment... CATEGORY Incandescent Lamp Envelope Manufacturing Subcategory § 426.120 Applicability; description of the incandescent lamp envelope manufacturing subcategory. The provisions of this subpart are applicable to...

Multidisciplinary aeroelastic analysis of a generic hypersonic vehicle

NASA Technical Reports Server (NTRS)

Gupta, K. K.; Petersen, K. L.

1993-01-01

This paper presents details of a flutter and stability analysis of aerospace structures such as hypersonic vehicles. Both structural and aerodynamic domains are discretized by the common finite element technique. A vibration analysis is first performed by the STARS code employing a block Lanczos solution scheme. This is followed by the generation of a linear aerodynamic grid for subsequent linear flutter analysis within subsonic and supersonic regimes of the flight envelope; the doublet lattice and constant pressure techniques are employed to generate the unsteady aerodynamic forces. Flutter analysis is then performed for several representative flight points. The nonlinear flutter solution is effected by first implementing a CFD solution of the entire vehicle. Thus, a 3-D unstructured grid for the entire flow domain is generated by a moving front technique. A finite element Euler solution is then implemented employing a quasi-implicit as well as an explicit solution scheme. A novel multidisciplinary analysis is next effected that employs modal and aerodynamic data to yield aerodynamic damping characteristics. Such analyses are performed for a number of flight points to yield a large set of pertinent data that define flight flutter characteristics of the vehicle. This paper outlines the finite-element-based integrated analysis procedures in detail, which is followed by the results of numerical analyses of flight flutter simulation.

Integral Field Spectroscopy of Supernova Remnant 1E0102–7219 Reveals Fast-moving Hydrogen and Sulfur-rich Ejecta

NASA Astrophysics Data System (ADS)

Seitenzahl, Ivo R.; Vogt, Frédéric P. A.; Terry, Jason P.; Ghavamian, Parviz; Dopita, Michael A.; Ruiter, Ashley J.; Sukhbold, Tuguldur

2018-02-01

We study the optical emission from heavy element ejecta in the oxygen-rich young supernova remnant 1E 0102.2–7219 (1E 0102) in the Small Magellanic Cloud. We have used the Multi-Unit Spectroscopic Explorer optical integral field spectrograph at the Very Large Telescope on Cerro Paranal and the wide field spectrograph (WiFeS) at the ANU 2.3 m telescope at Siding Spring Observatory to obtain deep observations of 1E 0102. Our observations cover the entire extent of the remnant from below 3500 Å to 9350 Å. Our observations unambiguously reveal the presence of fast-moving ejecta emitting in [S II], [S III], [Ar III], and [Cl II]. The sulfur-rich ejecta appear more asymmetrically distributed compared to oxygen or neon, a product of carbon burning. In addition to the forbidden line emission from products of oxygen burning (S, Ar, Cl), we have also discovered Hα and Hβ emission from several knots of low surface brightness, fast-moving ejecta. The presence of fast-moving hydrogen points toward a progenitor that had not entirely shed its hydrogen envelope prior to the supernova. The explosion that gave rise to 1E 0102 is therefore commensurate with a Type IIb supernova.

The use of specific antibodies to mediate fusion between Sendai virus envelopes and living cells.

PubMed

Loyter, A; Tomasi, M; Gitman, A G; Etinger, L; Nussbaum, O

1984-01-01

Incubation of Sendai virus particles with non-ionic detergents such as Triton X-100 completely solubilizes the viral envelopes. Removal of the detergent from the supernatant (which contains the two main viral glycoproteins) leads to the formation of fusogenic, reconstituted viral envelopes. Soluble macromolecules such as DNA or proteins can be enclosed within the reconstituted vesicles, while membrane components can be inserted into the viral envelopes. Fusion of such loaded or 'hybrid' reconstituted envelopes with living cells in culture results in either microinjection or transfer of the viral components to the recipient cells. Thus such reconstituted envelopes can serve as efficient carriers for the introduction of macromolecules of biological interest into living cells in culture. A more specific vehicle has been constructed by chemically coupling anti-cell membrane antibodies (anti-human erythrocyte antibody) to the viral envelope. Such antibody-bearing intact virus particles or reconstituted envelopes bound to and fused with virus receptor-depleted cells. In addition, anti-Sendai virus antibodies were coupled to neuraminidase-treated human erythrocytes. Such antibodies mediated the binding and fusion of intact Sendai virus particles and their reconstituted envelopes to virus receptor-depleted cells.

14 CFR 29.87 - Height-velocity envelope.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Category A engine isolation requirements, the height-velocity envelope for complete power failure must be... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Height-velocity envelope. 29.87 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Performance § 29.87 Height-velocity envelope. (a...

Russian Apartment Building Thermal Response Models for Retrofit Selection and Verification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Armstrong, Peter R.; Dirks, James A.; Reilly, Raymond W.

2000-08-21

The Enterprise Housing Divestiture Project (EHDP) aims to identify cost-effective energy efficiency and conservation measures for Russian apartment buildings and to implement these measures in the entire stock of buildings undergoing divestiture in six cities. Short-term measurements of infiltration and exterior wall heat-loss coefficient were made in the cities of Cheropovets, Orenburg, Petrozavodsk, Ryazan, and Vladimir. Long-term monitoring equipment was installed in six or more buildings in the aforementioned and in the city of Volxhov. The results of these measurements will be used to calibrate models used to select optimal retrofit packages and to verify energy savings. The retrofit categoriesmore » representing the largest technical potential in these buildings are envelope, heat recovery, and heating/hot water system improvements. This paper describes efforts to establish a useful thermal model calibration process. The model structures and analytical methods for obtaining building parameters from time series weather, energy use, and thermal response data are developed. Our experience applying these methods to two, nominally identical 5-story apartment buildings in the city of Ryazan is presented. Building envelope UA?s inferred from measured whole-building thermal response data are compared with UA?s based on window and wall U-values (the latter obtained by ASTM in-situ measurements of 20 wall sections in various Ryazan panel buildings) as well. The UA's obtained by these completely independent measurements differ by less than 10%.« less

Mass ejection in failed supernovae: variation with stellar progenitor

NASA Astrophysics Data System (ADS)

Fernández, Rodrigo; Quataert, Eliot; Kashiyama, Kazumi; Coughlin, Eric R.

2018-05-01

We study the ejection of mass during stellar core-collapse when the stalled shock does not revive and a black hole forms. Neutrino emission during the protoneutron star phase causes a decrease in the gravitational mass of the core, resulting in an outward going sound pulse that steepens into a shock as it travels out through the star. We explore the properties of this mass ejection mechanism over a range of stellar progenitors using spherically symmetric, time-dependent hydrodynamic simulations that treat neutrino mass-loss parametrically and follow the shock propagation over the entire star. We find that all types of stellar progenitor can eject mass through this mechanism. The ejected mass is a decreasing function of the surface gravity of the star, ranging from several M⊙ for red supergiants to ˜0.1 M⊙ for blue supergiants and ˜10-3 M⊙ for Wolf-Rayet stars. We find that the final shock energy at the surface is a decreasing function of the core-compactness, and is ≲ 1047-1048 erg in all cases. In progenitors with a sufficiently large envelope, high core-compactness, or a combination of both, the sound pulse fails to unbind mass. Successful mass ejection is accompanied by significant fallback accretion that can last from hours to years. We predict the properties of shock breakout and thermal plateau emission produced by the ejection of the outer envelope of blue supergiant and Wolf-Rayet progenitors in otherwise failed supernovae.

The evaluation of the OSGLR algorithm for restructurable controls

NASA Technical Reports Server (NTRS)

Bonnice, W. F.; Wagner, E.; Hall, S. R.; Motyka, P.

1986-01-01

The detection and isolation of commercial aircraft control surface and actuator failures using the orthogonal series generalized likelihood ratio (OSGLR) test was evaluated. The OSGLR algorithm was chosen as the most promising algorithm based on a preliminary evaluation of three failure detection and isolation (FDI) algorithms (the detection filter, the generalized likelihood ratio test, and the OSGLR test) and a survey of the literature. One difficulty of analytic FDI techniques and the OSGLR algorithm in particular is their sensitivity to modeling errors. Therefore, methods of improving the robustness of the algorithm were examined with the incorporation of age-weighting into the algorithm being the most effective approach, significantly reducing the sensitivity of the algorithm to modeling errors. The steady-state implementation of the algorithm based on a single cruise linear model was evaluated using a nonlinear simulation of a C-130 aircraft. A number of off-nominal no-failure flight conditions including maneuvers, nonzero flap deflections, different turbulence levels and steady winds were tested. Based on the no-failure decision functions produced by off-nominal flight conditions, the failure detection performance at the nominal flight condition was determined. The extension of the algorithm to a wider flight envelope by scheduling the linear models used by the algorithm on dynamic pressure and flap deflection was also considered. Since simply scheduling the linear models over the entire flight envelope is unlikely to be adequate, scheduling of the steady-state implentation of the algorithm was briefly investigated.

Efficiency Evaluations of U.S. Public Higher Education and Effects of State Funding and Pell Grants: Panel Data Estimates Using Two Stage Data Envelopment Analysis, 2004-2013 Academic Years

ERIC Educational Resources Information Center

Sav, G. Thomas

2017-01-01

The Great Recession induced by the financial crisis accelerated the decades of declining state funding support for U.S. public higher education, while simultaneously bringing increased political pressures for demonstrating improvements in the operating efficiencies among all universities and colleges. The purpose of this paper is twofold. First,…

Stability and control flight test results of the space transportation system's orbiter

NASA Technical Reports Server (NTRS)

Culp, M. A.; Cooke, D. R.

1982-01-01

Flight testing of the Space Shuttle Orbiter is in progress and current results of the post-flight aerodynamic analyses are discussed. The purpose of these analyses is to reduce the pre-flight aerodynamic uncertainties, thereby leading to operational certification of the Orbiter flight envelope relative to the integrated airframe and flight control system. Primary data reduction is accomplished with a well documented maximum likelihood system identification techniques.

Data Envelopment Analysis to Assess Productivity in the United States Air Force Medical Supply Chain

DTIC Science & Technology

2011-06-01

represented as the numerator in the following formula, rendering a “utilization” percentage ( Heizer & Render , 2008): Actual Output...when “it” is needed. ( Heizer & Render , 2008). While operating costs are certainly a deciding factor, the overarching importance of these decisions...designed to do at its maximum and what it actually does encouraged further review of this SLEF ( Heizer & Bender, 2008). The difference between

Operationally Responsive Space: Creating Responsive Space for America

DTIC Science & Technology

2008-06-20

programs. Items identified for improvement include: 1 ) Fractured management and accounting , 2 ) Satellite availability, 3) Facilities (Processing...enveloped by our three output tiers. The three tiers: • Tier 1 is an immediate response taking minutes to days. • Tier 2 is a mid term response taking...needs to improve. 2 . Develop a philosophy. 3. Set a direction with specific goals (Fuchs 1 -7). The Department of Space should follow these

Impact of the Local Public Hospital Reform on the Efficiency of Medium-Sized Hospitals in Japan: An Improved Slacks-Based Measure Data Envelopment Analysis Approach.

PubMed

Zhang, Xing; Tone, Kaoru; Lu, Yingzhe

2018-04-01

To assess the change in efficiency and total factor productivity (TFP) of the local public hospitals in Japan after the local public hospital reform launched in late 2007, which was aimed at improving the financial capability and operational efficiency of hospitals. Secondary data were collected from the Ministry of Internal Affairs and Communications on 213 eligible medium-sized hospitals, each operating 100-400 beds from FY2006 to FY2011. The improved slacks-based measure nonoriented data envelopment analysis models (Quasi-Max SBM nonoriented DEA models) were used to estimate dynamic efficiency score and Malmquist Index. The dynamic efficiency measure indicated an efficiency gain in the first several years of the reform and then was followed by a decrease. Malmquist Index analysis showed a significant decline in the TFP between 2006 and 2011. The financial improvement of medium-sized hospitals was not associated with enhancement of efficiency. Hospital efficiency was not significantly different among ownership structure and law-application system groups, but it was significantly affected by hospital location. The results indicate a need for region-tailored health care policies and for a more comprehensive reform to overcome the systemic constraints that might contribute to the decline of the TFP. © Health Research and Educational Trust.

Expanded envelope concepts for aircraft control-element failure detection and identification

NASA Technical Reports Server (NTRS)

Weiss, Jerold L.; Hsu, John Y.

1988-01-01

The purpose of this effort was to develop and demonstrate concepts for expanding the envelope of failure detection and isolation (FDI) algorithms for aircraft-path failures. An algorithm which uses analytic-redundancy in the form of aerodynamic force and moment balance equations was used. Because aircraft-path FDI uses analytical models, there is a tradeoff between accuracy and the ability to detect and isolate failures. For single flight condition operation, design and analysis methods are developed to deal with this robustness problem. When the departure from the single flight condition is significant, algorithm adaptation is necessary. Adaptation requirements for the residual generation portion of the FDI algorithm are interpreted as the need for accurate, large-motion aero-models, over a broad range of velocity and altitude conditions. For the decision-making part of the algorithm, adaptation may require modifications to filtering operations, thresholds, and projection vectors that define the various hypothesis tests performed in the decision mechanism. Methods of obtaining and evaluating adequate residual generation and decision-making designs have been developed. The application of the residual generation ideas to a high-performance fighter is demonstrated by developing adaptive residuals for the AFTI-F-16 and simulating their behavior under a variety of maneuvers using the results of a NASA F-16 simulation.

Review of life-cycle approaches coupled with data envelopment analysis: launching the CFP + DEA method for energy policy making.

PubMed

Vázquez-Rowe, Ian; Iribarren, Diego

2015-01-01

Life-cycle (LC) approaches play a significant role in energy policy making to determine the environmental impacts associated with the choice of energy source. Data envelopment analysis (DEA) can be combined with LC approaches to provide quantitative benchmarks that orientate the performance of energy systems towards environmental sustainability, with different implications depending on the selected LC + DEA method. The present paper examines currently available LC + DEA methods and develops a novel method combining carbon footprinting (CFP) and DEA. Thus, the CFP + DEA method is proposed, a five-step structure including data collection for multiple homogenous entities, calculation of target operating points, evaluation of current and target carbon footprints, and result interpretation. As the current context for energy policy implies an anthropocentric perspective with focus on the global warming impact of energy systems, the CFP + DEA method is foreseen to be the most consistent LC + DEA approach to provide benchmarks for energy policy making. The fact that this method relies on the definition of operating points with optimised resource intensity helps to moderate the concerns about the omission of other environmental impacts. Moreover, the CFP + DEA method benefits from CFP specifications in terms of flexibility, understanding, and reporting.

Review of Life-Cycle Approaches Coupled with Data Envelopment Analysis: Launching the CFP + DEA Method for Energy Policy Making

PubMed Central

Vázquez-Rowe, Ian

2015-01-01

Life-cycle (LC) approaches play a significant role in energy policy making to determine the environmental impacts associated with the choice of energy source. Data envelopment analysis (DEA) can be combined with LC approaches to provide quantitative benchmarks that orientate the performance of energy systems towards environmental sustainability, with different implications depending on the selected LC + DEA method. The present paper examines currently available LC + DEA methods and develops a novel method combining carbon footprinting (CFP) and DEA. Thus, the CFP + DEA method is proposed, a five-step structure including data collection for multiple homogenous entities, calculation of target operating points, evaluation of current and target carbon footprints, and result interpretation. As the current context for energy policy implies an anthropocentric perspective with focus on the global warming impact of energy systems, the CFP + DEA method is foreseen to be the most consistent LC + DEA approach to provide benchmarks for energy policy making. The fact that this method relies on the definition of operating points with optimised resource intensity helps to moderate the concerns about the omission of other environmental impacts. Moreover, the CFP + DEA method benefits from CFP specifications in terms of flexibility, understanding, and reporting. PMID:25654136

A systematic methodology for the robust quantification of energy efficiency at wastewater treatment plants featuring Data Envelopment Analysis.

PubMed

Longo, S; Hospido, A; Lema, J M; Mauricio-Iglesias, M

2018-05-10

This article examines the potential benefits of using Data Envelopment Analysis (DEA) for conducting energy-efficiency assessment of wastewater treatment plants (WWTPs). WWTPs are characteristically heterogeneous (in size, technology, climate, function …) which limits the correct application of DEA. This paper proposes and describes the Robust Energy Efficiency DEA (REED) in its various stages, a systematic state-of-the-art methodology aimed at including exogenous variables in nonparametric frontier models and especially designed for WWTP operation. In particular, the methodology systematizes the modelling process by presenting an integrated framework for selecting the correct variables and appropriate models, possibly tackling the effect of exogenous factors. As a result, the application of REED improves the quality of the efficiency estimates and hence the significance of benchmarking. For the reader's convenience, this article is presented as a step-by-step guideline to guide the user in the determination of WWTPs energy efficiency from beginning to end. The application and benefits of the developed methodology are demonstrated by a case study related to the comparison of the energy efficiency of a set of 399 WWTPs operating in different countries and under heterogeneous environmental conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.

General aviation accidents related to exceedance of airplane weight/center of gravity limits.

PubMed

Boyd, Douglas D

2016-06-01

Obesity, affects a third of the US population and its corollary occupant weight adversely impacts safe flight operations. Increased aircraft weight results in longer takeoff/landing distances, degraded climb gradients and airframe failure may occur in turbulence. In this study, the rate, temporal changes, and lethality of accidents in piston-powered, general aviation aircraft related to exceeding the maximum aircraft weight/center of gravity (CG) limits were determined. Nation-wide person body mass were from the National Health and Nutrition Examination Survey. The NTSB database was used to identify accidents related to operation of aircraft outside of their weight/CG envelope. Statistical analyses employed T-tests, proportion tests and a Poisson distribution. While the average body mass climbed steadily (p<0.001) between 1999 and 2014 the rate of accidents related to exceedance of the weight/CG limits did not change (p=0.072). However, 57% were fatal, higher (p<0.001) than the 21% for mishaps attributed to other causes/factors. The majority (77%) of accidents were due to an overloaded aircraft operating within its CG limits. As to the phase of flight, accidents during takeoff and those occurring enroute carried the lowest (50%) and highest (85%) proportion of fatal accidents respectively. While the rate of general aviation accidents related to operating an aircraft outside of its weight/CG envelope has not increased over the past 15 years, these types of accidents carry a high risk of fatality. Airmen should be educated as to such risks and to dispel the notion held by some that flights may be safely conducted with an overloaded aircraft within its CG limits. Copyright © 2016 Elsevier Ltd. All rights reserved.

CPLOAS_2 User Manual.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sallaberry, Cedric Jean-Marie; Helton, Jon C.

2015-05-01

Weak link (WL)/strong link (SL) systems are important parts of the overall operational design of high - consequence systems. In such designs, the SL system is very robust and is intended to permit operation of the entire system under, and only under, intended conditions. In contrast, the WL system is intended to fail in a predictable and irreversible manner under accident conditions and render the entire system inoperable before an accidental operation of the SL system. The likelihood that the WL system will fail to d eactivate the entire system before the SL system fails (i.e., degrades into a configurationmore » that could allow an accidental operation of the entire system) is referred to as probability of loss of assured safety (PLOAS). This report describes the Fortran 90 program CPLOAS_2 that implements the following representations for PLOAS for situations in which both link physical properties and link failure properties are time - dependent: (i) failure of all SLs before failure of any WL, (ii) failure of any SL before f ailure of any WL, (iii) failure of all SLs before failure of all WLs, and (iv) failure of any SL before failure of all WLs. The effects of aleatory uncertainty and epistemic uncertainty in the definition and numerical evaluation of PLOAS can be included in the calculations performed by CPLOAS_2. Keywords: Aleatory uncertainty, CPLOAS_2, Epistemic uncertainty, Probability of loss of assured safety, Strong link, Uncertainty analysis, Weak link« less

Nonstationary envelope process and first excursion probability.

NASA Technical Reports Server (NTRS)

Yang, J.-N.

1972-01-01

The definition of stationary random envelope proposed by Cramer and Leadbetter, is extended to the envelope of nonstationary random process possessing evolutionary power spectral densities. The density function, the joint density function, the moment function, and the crossing rate of a level of the nonstationary envelope process are derived. Based on the envelope statistics, approximate solutions to the first excursion probability of nonstationary random processes are obtained. In particular, applications of the first excursion probability to the earthquake engineering problems are demonstrated in detail.

National Counterdrug Center (NCC) Simulation System Operational Requirements Document (ORD) Version 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holter, Gregory M

2001-01-26

This Operational Requirements Document (ORD) describes the capabilities that need to be incorporated in the NCC interactive simulation system being developed under the auspices of the NCC development program. The ORD addresses the necessary capabilities (i.e. what the system needs to be able to do); it defines the envelope of situations and circumstances that the NCC system must be able to represent and operate within. The NCC system will be developed in modules over a period of several years. This ORD, Version 2, supersedes the previous version. Future updates of this ORD are anticipated to be issued as needed tomore » guide the development of later versions of the NCC system.« less

Low thrust rocket test facility

NASA Technical Reports Server (NTRS)

Arrington, Lynn A.; Schneider, Steven J.

1990-01-01

A low thrust chemical rocket test facility has recently become operational at the NASA-Lewis. The new facility is used to conduct both long duration and performance tests at altitude over a thruster's operating envelope using hydrogen and oxygen gas for propellants. The facility provides experimental support for a broad range of objectives, including fundamental modeling of fluids and combustion phenomena, the evaluation of thruster components, and life testing of full rocket designs. The major mechanical and electrical systems are described along with aspects of the various optical diagnostics available in the test cell. The electrical and mechanical systems are designed for low down time between tests and low staffing requirements for test operations. Initial results are also presented which illustrate the various capabilities of the cell.

Dynamics of core accretion

DOE PAGES

Nelson, Andrew F.; Ruffert, Maximilian

2012-12-21

In this paper, we perform three-dimensional hydrodynamic simulations of gas flowing around a planetary core of mass M pl = 10M ⊕ embedded in a near Keplerian background flow, using a modified shearing box approximation. We assume an ideal gas behaviour following an equation of state with a fixed ratio of the specific heats, γ = 1.42, consistent with the conditions of a moderate-temperature background disc with solar composition. No radiative heating or cooling is included in the models. We employ a nested grid hydrodynamic code implementing the ‘Piecewise Parabolic Method’ with as many as six fixed nested grids, providingmore » spatial resolution on the finest grid comparable to the present-day diameters of Neptune and Uranus. We find that a strongly dynamically active flow develops such that no static envelope can form. The activity is not sensitive to plausible variations in the rotation curve of the underlying disc. It is sensitive to the thermodynamic treatment of the gas, as modelled by prescribed equations of state (either ‘locally isothermal’ or ‘locally isentropic’) and the temperature of the background disc material. The activity is also sensitive to the shape and depth of the core's gravitational potential, through its mass and gravitational softening coefficient. Each of these factors influences the magnitude and character of hydrodynamic feedback of the small-scale flow on the background, and we conclude that accurate modelling of such feedback is critical to a complete understanding of the core accretion process. The varying flow pattern gives rise to large, irregular eruptions of matter from the region around the core which return matter to the background flow: mass in the envelope at one time may not be found in the envelope at any later time. No net mass accretion into the envelope is observed over the course of the simulation and none is expected, due to our neglect of cooling. Except in cases of very rapid cooling however, as defined by locally isothermal or isentropic treatments, any cooling that does affect the envelope material will have limited consequences for the dynamics, since the flow quickly carries cooled material out of the core's environment entirely. The angular momentum of material in the envelope, relative to the core, varies both in magnitude and in sign on time-scales of days to months near the core and on time-scales a few years at distances comparable to the Hill radius. The dynamical activity contrasts with the largely static behaviour typically assumed within the framework of the core accretion model for Jovian planet formation. We show that material entering the dynamically active environment may suffer intense heating and cooling events the durations of which are as short as a few hours to a few days. Shorter durations are not observable in our work due to the limits of our resolution. Peak temperatures in these events range from T ~ 1000 K to as high as T ~ 3–4000 K, with densities ρ ~ 10 -9 to 10 -8 gcm -3. These time-scales, densities and temperatures span a range consistent with those required for chondrule formation in the nebular shock model. Finally, we therefore propose that dynamical activity in the Jovian planet formation environment could be responsible for the production of chondrules and other annealed silicates in the solar nebula.« less

Dynamics of core accretion

NASA Astrophysics Data System (ADS)

Nelson, Andrew F.; Ruffert, Maximilian

2013-02-01

We perform three-dimensional hydrodynamic simulations of gas flowing around a planetary core of mass Mpl = 10M⊕ embedded in a near Keplerian background flow, using a modified shearing box approximation. We assume an ideal gas behaviour following an equation of state with a fixed ratio of the specific heats, γ = 1.42, consistent with the conditions of a moderate-temperature background disc with solar composition. No radiative heating or cooling is included in the models. We employ a nested grid hydrodynamic code implementing the `Piecewise Parabolic Method' with as many as six fixed nested grids, providing spatial resolution on the finest grid comparable to the present-day diameters of Neptune and Uranus. We find that a strongly dynamically active flow develops such that no static envelope can form. The activity is not sensitive to plausible variations in the rotation curve of the underlying disc. It is sensitive to the thermodynamic treatment of the gas, as modelled by prescribed equations of state (either `locally isothermal' or `locally isentropic') and the temperature of the background disc material. The activity is also sensitive to the shape and depth of the core's gravitational potential, through its mass and gravitational softening coefficient. Each of these factors influences the magnitude and character of hydrodynamic feedback of the small-scale flow on the background, and we conclude that accurate modelling of such feedback is critical to a complete understanding of the core accretion process. The varying flow pattern gives rise to large, irregular eruptions of matter from the region around the core which return matter to the background flow: mass in the envelope at one time may not be found in the envelope at any later time. No net mass accretion into the envelope is observed over the course of the simulation and none is expected, due to our neglect of cooling. Except in cases of very rapid cooling however, as defined by locally isothermal or isentropic treatments, any cooling that does affect the envelope material will have limited consequences for the dynamics, since the flow quickly carries cooled material out of the core's environment entirely. The angular momentum of material in the envelope, relative to the core, varies both in magnitude and in sign on time-scales of days to months near the core and on time-scales a few years at distances comparable to the Hill radius. The dynamical activity contrasts with the largely static behaviour typically assumed within the framework of the core accretion model for Jovian planet formation. We show that material entering the dynamically active environment may suffer intense heating and cooling events the durations of which are as short as a few hours to a few days. Shorter durations are not observable in our work due to the limits of our resolution. Peak temperatures in these events range from T ˜ 1000 K to as high as T ˜ 3-4000 K, with densities ρ ˜ 10-9 to 10-8 g cm-3. These time-scales, densities and temperatures span a range consistent with those required for chondrule formation in the nebular shock model. We therefore propose that dynamical activity in the Jovian planet formation environment could be responsible for the production of chondrules and other annealed silicates in the solar nebula.

Differential Rotation in Sun-like Stars from Surface Variability and Asteroseismology

NASA Astrophysics Data System (ADS)

Nielsen, Martin Bo

2017-03-01

The Sun and other stars are known to oscillate. Through the study of small perturbations to the frequencies of these oscillations the rotation of the deep interior can be inferred. However, thus far the internal rotation of other Sun-like stars is unknown. The NASA Kepler mission has observed a multitude of Sun-like stars over a period of four years. This has provided high-quality photometric data that can be used to study the rotation of stars with two different techniques: asteroseismology and surface activity. Asteroseismology provides a means of measuring rotation in the stellar interior, while photometric variability from magnetically active regions are sensitive to rotation at the stellar surface. The combination of these two methods can be used to constrain the radial differential rotation in Sun-like stars. First, we developed an automated method for measuring the rotation of stars using surface variability. This method was initially applied to the entire Kepler catalog, out of which we detected signatures of rotation in 12,000 stars across the main sequence, providing robust estimates of the surface rotation rates and the associated errors. Second, we performed an asteroseismic analysis of six Sun-like stars, where we were able to measure the rotational splitting as a function of frequency in the p-mode envelope. This was done by dividing the oscillation spectrum into individual segments, and fitting a model independently to each segment. We found that the measured splittings were all consistent with a constant value, indicating little differential rotation. Third, we compared the asteroseismic rotation rates of five Sun-like stars to their surface rotation rates. We found that the values were in good agreement, again indicating little differential rotation between the regions where the two methods are most sensitive. Finally, we discuss how the surface rotation rates may be used as a prior on the seismic envelope rotation rate in a double-zone model, consisting of an independently-rotating radiative interior and convective envelope. Using such a prior we find that the rotation rates of the radiative interior and convective envelope likely do not differ by more than 50%. This further supports the idea that Sun-like stars likely show a rotation pattern similar to that of the Sun. Results from the analysis presented herein provide physical limits on the internal differential rotation of Sun-like stars, and show that this method may be easily applied to a wider variety of stars.

Low power arcjet performance

NASA Technical Reports Server (NTRS)

Curran, Francis M.; Sarmiento, Charles J.

1990-01-01

An experimental investigation was performed to evaluate arc jet operation at low power. A standard, 1 kW, constricted arc jet was run using nozzles with three different constrictor diameters. Each nozzle was run over a range of current and mass flow rates to explore stability and performance in the low power engine. A standard pulse-width modulated power processor was modified to accommodate the high operating voltages required under certain conditions. Stable, reliable operation at power levels below 0.5 kW was obtained at efficiencies between 30 and 40 percent. The operating range was found to be somewhat dependent on constrictor geometry at low mass flow rates. Quasi-periodic voltage fluctuations were observed at the low power end of the operating envelope, The nozzle insert geometry was found to have little effect on the performance of the device. The observed performance levels show that specific impulse levels above 350 seconds can be obtained at the 0.5 kW power level.

Low power arcjet performance

NASA Technical Reports Server (NTRS)

Curran, Francis M.; Sarmiento, Charles J.

1990-01-01

An experimental investigation was performed to evaluate arcjet operation at low power. A standard, 1 kW, constricted arcjet was run using nozzles with three different constrictor diameters. Each nozzle was run over a range of current and mass flow rates to explore stability and performance in the low power regime. A standard pulse-width modulated power processor was modified to accommodate the high operating voltages required under certain conditions. Stable, reliable operation at power levels below 0.5 kW was obtained at efficiencies between 30 and 40 percent. The operating range was found to be somewhat dependent on constrictor geometry at low mass flow rates. Quasi-periodic voltage fluctuations were observed at the low power end of the operating envelope. The nozzle insert geometry was found to have little effect on the performance of the device. The observed performance levels show that specific impulse levels above 350 seconds can be obtained at the 0.5 kW power level.

Hydrogen-Oxygen PEM Regenerative Fuel Cell Development at the NASA Glenn Research Center

NASA Technical Reports Server (NTRS)

Bents, David J.; Scullin, Vincent J.; Chang, Bei-Jiann; Johnson, Donald W.; Garcia, Christoher P.; Jakupca, Ian J.

2005-01-01

The closed-cycle hydrogen-oxygen PEM regenerative fuel cell (RFC) at the NASA Glenn Research Center has successfully demonstrated closed cycle operation at rated power for multiple charge-discharge cycles. During charge cycle the RFC has absorbed input electrical power simulating a solar day cycle ranging from zero to 15 kWe peak, and delivered steady 5 kWe output power for periods exceeding 8 hr. Orderly transitions from charge to discharge mode, and return to charging after full discharge, have been accomplished without incident. Continuing test operations focus on: (1) Increasing the number of contiguous uninterrupted charge discharge cycles; (2) Increasing the performance envelope boundaries; (3) Operating the RFC as an energy storage device on a regular basis; (4) Gaining operational experience leading to development of fully automated operation; and (5) Developing instrumentation and in situ fluid sampling strategies to monitor health and anticipate breakdowns.

Inability of keratinocytes lacking their specific transglutaminase to form cross-linked envelopes: absence of envelopes as a simple diagnostic test for lamellar ichthyosis.

PubMed

Jeon, S; Djian, P; Green, H

1998-01-20

Epidermal keratinocytes, late in their terminal differentiation, form cross-linked envelopes resistant to ionic detergent and reducing agent. Because the cross-linking process is catalyzed by the keratinocyte transglutaminase, the absence of active transglutaminase should result in failure of the keratinocyte to form a cross-linked envelope. Three keratinocyte strains bearing mutations in the keratinocyte transglutaminase were examined: two contained no detectable transglutaminase mRNA and none contained active enzyme. All three were unable to form cross-linked envelopes, either spontaneously in stratified cultures or upon induction with Ca2+. Although stratum corneum of normal humans and scales from patients with different ichthyotic diseases contain cross-linked envelopes, those from patients with transglutaminase-negative lamellar ichthyosis do not. Therefore, the disease due to the absence of transglutaminase may be readily distinguished from other ichthyotic disease by a simple test for cross-linked envelopes.

The influence of grain growth in circumstellar dust envelopes on observed colors and polarization of some eruptive stars

NASA Technical Reports Server (NTRS)

Efimov, Yu. S.

1989-01-01

R CrB stars are classical examples of stars where dust envelope formation takes place. Dust envelope formation was detected around the Kuwano-Honda object (PU Vul) in 1980 to 1981 when the star's brightness fell to 8(sup m). Such envelopes are also formed at nova outbursts. The process of dust envelope formation leads to appreciable variations in optical characteristics, which are seen in specific color and polarization variations in the course of light fading and the appearance of IR radiation. It is shown that the model of a circumstellar dust envelope with aligned particles of changing size can be successfully applied to explain most phenomena observed at the time of light minima for a number of eruptive stars. The polarization may arise in a nonspherical dust envelope or be produced by alignment of nonspherical particles.

Application of the Envelope Difference Index to Spectrally Sparse Speech

ERIC Educational Resources Information Center

Souza, Pamela; Hoover, Eric; Gallun, Frederick

2012-01-01

Purpose: Amplitude compression is a common hearing aid processing strategy that can improve speech audibility and loudness comfort but also has the potential to alter important cues carried by the speech envelope. In previous work, a measure of envelope change, the Envelope Difference Index (EDI; Fortune, Woodruff, & Preves, 1994), was moderately…

Enveloping Aerodynamic Decelerator

NASA Technical Reports Server (NTRS)

Nock, Kerry T. (Inventor); Aaron, Kim M. (Inventor); McRonald, Angus D. (Inventor); Gates, Kristin L. (Inventor)

2018-01-01

An inflatable aerodynamic deceleration method and system is provided for use with an atmospheric entry payload. The inflatable aerodynamic decelerator includes an inflatable envelope and an inflatant, wherein the inflatant is configured to fill the inflatable envelope to an inflated state such that the inflatable envelope surrounds the atmospheric entry payload, causing aerodynamic forces to decelerate the atmospheric entry payload.

Propolis envelope in Apis mellifera colonies supports honey bees against the pathogen, Paenibacillus larvae.

PubMed

Borba, Renata S; Spivak, Marla

2017-09-12

Honey bees have immune defenses both as individuals and as a colony (e.g., individual and social immunity). One form of honey bee social immunity is the collection of antimicrobial plant resins and the deposition of the resins as a propolis envelope within the nest. In this study, we tested the effects of the propolis envelope as a natural defense against Paenibacillus larvae, the causative agent of American foulbrood (AFB) disease. Using colonies with and without a propolis envelope, we quantified: 1) the antimicrobial activity of larval food fed to 1-2 day old larvae; and 2) clinical signs of AFB. Our results show that the antimicrobial activity of larval food was significantly higher when challenged colonies had a propolis envelope compared to colonies without the envelope. In addition, colonies with a propolis envelope had significantly reduced levels of AFB clinical signs two months following challenge. Our results indicate that the propolis envelope serves as an antimicrobial layer around the colony that helps protect the brood from bacterial pathogen infection, resulting in a lower colony-level infection load.

Nuclear envelope breakdown induced by herpes simplex virus type 1 involves the activity of viral fusion proteins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maric, Martina; Haugo, Alison C.; Dauer, William

2014-07-15

Herpesvirus infection reorganizes components of the nuclear lamina usually without loss of integrity of the nuclear membranes. We report that wild-type HSV infection can cause dissolution of the nuclear envelope in transformed mouse embryonic fibroblasts that do not express torsinA. Nuclear envelope breakdown is accompanied by an eight-fold inhibition of virus replication. Breakdown of the membrane is much more limited during infection with viruses that lack the gB and gH genes, suggesting that breakdown involves factors that promote fusion at the nuclear membrane. Nuclear envelope breakdown is also inhibited during infection with virus that does not express UL34, but ismore » enhanced when the US3 gene is deleted, suggesting that envelope breakdown may be enhanced by nuclear lamina disruption. Nuclear envelope breakdown cannot compensate for deletion of the UL34 gene suggesting that mixing of nuclear and cytoplasmic contents is insufficient to bypass loss of the normal nuclear egress pathway. - Highlights: • We show that wild-type HSV can induce breakdown of the nuclear envelope in a specific cell system. • The viral fusion proteins gB and gH are required for induction of nuclear envelope breakdown. • Nuclear envelope breakdown cannot compensate for deletion of the HSV UL34 gene.« less

Measuring Efficiency of Knowledge Production in Health Research Centers Using Data Envelopment Analysis (DEA): A Case Study in Iran

PubMed Central

Amiri, Mohammad Meskarpour; Nasiri, Taha; Saadat, Seyed Hassan; Anabad, Hosein Amini; Ardakan, Payman Mahboobi

2016-01-01

Introduction Efficiency analysis is necessary in order to avoid waste of materials, energy, effort, money, and time during scientific research. Therefore, analyzing efficiency of knowledge production in health areas is necessary, especially for developing and in-transition countries. As the first step in this field, the aim of this study was the analysis of selected health research center efficiency using data envelopment analysis (DEA). Methods This retrospective and applied study was conducted in 2015 using input and output data of 16 health research centers affiliated with a health sciences university in Iran during 2010–2014. The technical efficiency of health research centers was evaluated based on three basic data envelopment analysis (DEA) models: input-oriented, output-oriented, and hyperbolic-oriented. The input and output data of each health research center for years 2010–2014 were collected from the Iran Ministry of Health and Medical Education (MOHE) profile and analyzed by R software. Results The mean efficiency score in input-oriented, output-oriented, and hyperbolic-oriented models was 0.781, 0.671, and 0.798, respectively. Based on results of the study, half of the health research centers are operating below full efficiency, and about one-third of them are operating under the average efficiency level. There is also a large gap between health research center efficiency relative to each other. Conclusion It is necessary for health research centers to improve their efficiency in knowledge production through better management of available resources. The higher level of efficiency in a significant number of health research centers is achievable through more efficient management of human resources and capital. Further research is needed to measure and follow the efficiency of knowledge production by health research centers around the world and over a period of time. PMID:28344756

Comprehensive analysis of transport aircraft flight performance

NASA Astrophysics Data System (ADS)

Filippone, Antonio

2008-04-01

This paper reviews the state-of-the art in comprehensive performance codes for fixed-wing aircraft. The importance of system analysis in flight performance is discussed. The paper highlights the role of aerodynamics, propulsion, flight mechanics, aeroacoustics, flight operation, numerical optimisation, stochastic methods and numerical analysis. The latter discipline is used to investigate the sensitivities of the sub-systems to uncertainties in critical state parameters or functional parameters. The paper discusses critically the data used for performance analysis, and the areas where progress is required. Comprehensive analysis codes can be used for mission fuel planning, envelope exploration, competition analysis, a wide variety of environmental studies, marketing analysis, aircraft certification and conceptual aircraft design. A comprehensive program that uses the multi-disciplinary approach for transport aircraft is presented. The model includes a geometry deck, a separate engine input deck with the main parameters, a database of engine performance from an independent simulation, and an operational deck. The comprehensive code has modules for deriving the geometry from bitmap files, an aerodynamics model for all flight conditions, a flight mechanics model for flight envelopes and mission analysis, an aircraft noise model and engine emissions. The model is validated at different levels. Validation of the aerodynamic model is done against the scale models DLR-F4 and F6. A general model analysis and flight envelope exploration are shown for the Boeing B-777-300 with GE-90 turbofan engines with intermediate passenger capacity (394 passengers in 2 classes). Validation of the flight model is done by sensitivity analysis on the wetted area (or profile drag), on the specific air range, the brake-release gross weight and the aircraft noise. A variety of results is shown, including specific air range charts, take-off weight-altitude charts, payload-range performance, atmospheric effects, economic Mach number and noise trajectories at F.A.R. landing points.

Aerostructural optimization of a morphing wing for airborne wind energy applications

NASA Astrophysics Data System (ADS)

Fasel, U.; Keidel, D.; Molinari, G.; Ermanni, P.

2017-09-01

Airborne wind energy (AWE) vehicles maximize energy production by constantly operating at extreme wing loading, permitted by high flight speeds. Additionally, the wide range of wind speeds and the presence of flow inhomogeneities and gusts create a complex and demanding flight environment for AWE systems. Adaptation to different flow conditions is normally achieved by conventional wing control surfaces and, in case of ground generator-based systems, by varying the reel-out speed. These control degrees of freedom enable to remain within the operational envelope, but cause significant penalties in terms of energy output. A significantly greater adaptability is offered by shape-morphing wings, which have the potential to achieve optimal performance at different flight conditions by tailoring their airfoil shape and lift distribution at different levels along the wingspan. Hence, the application of compliant structures for AWE wings is very promising. Furthermore, active gust load alleviation can be achieved through morphing, which leads to a lower weight and an expanded flight envelope, thus increasing the power production of the AWE system. This work presents a procedure to concurrently optimize the aerodynamic shape, compliant structure, and composite layup of a morphing wing for AWE applications. The morphing concept is based on distributed compliance ribs, actuated by electromechanical linear actuators, guiding the deformation of the flexible—yet load-carrying—composite skin. The goal of the aerostructural optimization is formulated as a high-level requirement, namely to maximize the average annual power production per wing area of an AWE system by tailoring the shape of the wing, and to extend the flight envelope of the wing by actively alleviating gust loads. The results of the concurrent multidisciplinary optimization show a 50.7% increase of extracted power with respect to a sequentially optimized design, highlighting the benefits of morphing and the potential of the proposed approach.

Testing the Definition of the ESC Envelope

NASA Technical Reports Server (NTRS)

Vincent, Mark A.

2017-01-01

The previous effort, including a successful Change Control Request, addressed shrinking the size of the Earth Science Constellations' (ESC) Envelope by reducing the Margin. Fundamental to the purpose of the Envelope is the case where the argument of perigee of the secondary object circulates from 90 degrees to 270 degrees. This ("outside of the envelope, always outside the envelope") case was tested both numerically in a spreadsheet and analytically. Results showed how it is important to include the fact that a secondary with a different semi-major axis has a different frozen eccentricity value.

Circumstellar chemistry

NASA Technical Reports Server (NTRS)

Glassgold, Alfred E.; Huggins, Patrick J.

1987-01-01

The study of the outer envelopes of cool evolved stars has become an active area of research. The physical properties of CS envelopes are presented. Observations of many wavelengths bands are relevant. A summary of observations and a discussion of theoretical considerations concerning the chemistry are summarized. Recent theoretical considerations show that the thermal equilibrium model is of limited use for understanding the chemistry of the outer CS envelopes. The theoretical modeling of the chemistry of CS envelopes provides a quantitive test of chemical concepts which have a broader interest than the envelopes themselves.

Few-cycle carrier envelope phase-dependent stereo detection of electrons.

PubMed

Verhoef, Aart J; Fernández, Alma; Lezius, Matthias; O'Keeffe, Kevin; Uiberacker, Matthias; Krausz, Ferenc

2006-12-01

The spatial distribution of electrons emitted from atoms by few-cycle optical fields is known to be dependent on the carrier envelope phase, i.e., the phase of the field with respect to the pulse envelope. With respect to Paulus et al. [Phys. Rev. Lett.91, 253004 (2003)] we propose a greatly simplified device to measure and control the carrier envelope phase of few-cycle pulses with an accuracy of better than pi/10 based on this principle. We compared different schemes to control the carrier envelope phase of our pulses.

Performance documentation of the engineering model 30-cm diameter thruster

NASA Technical Reports Server (NTRS)

Bechtel, R. T.; Rawlin, V. K.

1976-01-01

The results of extensive testing of two 30-cm ion thrusters which are virtually identical to the 900 series Engineering Model Thruster in an ongoing 15,000-hour life test are presented. Performance data for the nominal fullpower (2650 W) operating point; performance sensitivities to discharge voltage, discharge losses, accelerator voltage, and magnetic baffle current; and several power throttling techniques (maximum Isp, maximum thrust/power ratio, and two cases in between are included). Criteria for throttling are specified in terms of the screen power supply envelope, thruster operating limits, and control stability. In addition, reduced requirements for successful high voltage recycles are presented.

Optics and materials research for controlled radiant energy transfer in buildings

NASA Astrophysics Data System (ADS)

Goldner, R. B.

1983-11-01

The overall objective of the Tufts research program was to identify and attempt to solve some of the key materials problems associated with practical approaches for achieving controlled radiant energy transfer (CRET) through building windows and envelopes, so as to decrease heating and cooling loads in buildings. Major accomplishments included: the identification of electrochromic (EC)-based structures as the preferred structures for achieving CRET; the identification of modulated reflectivity as the preferred mode of operation for EC-based structures; demonstration of the feasibility of operating EC-materials in a modulated R(lambda) mode; and demonstration of the applicability of free electron model to colored polycrystalline WO3 films.

Surgical treatment of intra-articular calcaneal fractures.

PubMed

Stapleton, John J; Zgonis, Thomas

2014-10-01

Most intra-articular calcaneal fractures are a result of high-energy trauma. The operative management of calcaneal fractures has been based on achieving anatomic reduction and minimizing complications of the compromised soft tissue envelope. The traditional extensile lateral approach offers advantages of achieving adequate fracture reduction with the risk of wound-healing complications and infection. Limited open reduction and internal fixation techniques with or without using external fixation focuses on achieving fracture reduction with less risk of wound complications but higher risk of malunion. This article discusses key points of operative management for various intra-articular calcaneal fracture patterns and clinical presentations. Copyright © 2014 Elsevier Inc. All rights reserved.

Shuttle vehicle and mission simulation requirements report, volume 1

NASA Technical Reports Server (NTRS)

Burke, J. F.

1972-01-01

The requirements for the space shuttle vehicle and mission simulation are developed to analyze the systems, mission, operations, and interfaces. The requirements are developed according to the following subject areas: (1) mission envelope, (2) orbit flight dynamics, (3) shuttle vehicle systems, (4) external interfaces, (5) crew procedures, (6) crew station, (7) visual cues, and (8) aural cues. Line drawings and diagrams of the space shuttle are included to explain the various systems and components.

Tactical Reconnaissance: UAVS Versus Manned Aircraft

DTIC Science & Technology

1997-03-01

level missions under the missile and radar detection envelope. It flew 1651 missions with a return rate of 87.2%. 3 The development of newer and more... level . The organizational structure of manned aircraft squadrons is therefore time tested and clearly defined. 12 By contrast UAV operations have had a ... a high level of information and sensor technology is available today it has been integrated to only a fraction of its combat potential following the

Recent Enhancements to the National Transonic Facility

NASA Technical Reports Server (NTRS)

Kilgore, W. A.; Balakrishna, S.; Bobbitt, C. W.; Underwood, P.

2003-01-01

The National Transonic Facility continues to make enhancements to provide quality data in a safe, efficient and cost effective method for aerodynamic ground testing. Recent enhancements discussed in this paper include the restoration of reliability and improved performance of the heat exchanger systems resulting in the expansion of the NTF air operations envelope. Additionally, results are presented from a continued effort to reduce model dynamics through the use of a new stiffer balance and sting

47 CFR 25.218 - Off-axis EIRP envelopes for FSS earth station operations.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) ESV and VMES applications, (2) Analog video earth station applications, (3) Applications for feeder... ≤ 7° 0 dBW/4 kHz For 7° 18 dBW/4 kHz For 48° 18 dBW/4 kHz For 48° < θ ≤ 85° −8 dBW/4 kHz For 85° < θ ≤ 180° where θ is defined in...

47 CFR 25.218 - Off-axis EIRP envelopes for FSS earth station operations.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) ESV and VMES applications, (2) Analog video earth station applications, (3) Applications for feeder... ≤ 7° 0 dBW/4 kHz For 7° 18 dBW/4 kHz For 48° 18 dBW/4 kHz For 48° < θ ≤ 85° −8 dBW/4 kHz For 85° < θ ≤ 180° where θ is defined in...

47 CFR 25.218 - Off-axis EIRP envelopes for FSS earth station operations.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) ESV and VMES applications, (2) Analog video earth station applications, (3) Applications for feeder... ≤ 7° 0 dBW/4 kHz For 7° 18 dBW/4 kHz For 48° 18 dBW/4 kHz For 48° < θ ≤ 85° −8 dBW/4 kHz For 85° < θ ≤ 180° where θ is defined in...

Mechanism of Dissolution of Envelopes of the Extreme Halophile Halobacterium cutirubrum1

PubMed Central

Onishi, H.; Kushner, D. J.

1966-01-01

Onishi, H. (National Research Council, Ottawa, Ontario, Canada), and D. J. Kushner. Mechanism of dissolution of envelopes of the extreme halophile Halobacterium cutirubrum. J. Bacteriol. 91:646–652. 1966.—Envelopes of Halobacterium cutirubrum dissolved rapidly in media of low ionic strength. Heating partially inhibited breakdown, probably because of nonspecific protein coagulation rather than inactivation of a lytic enzyme(s). Dissolution of envelopes in water did not involve splitting of peptide bonds or protein-lipid bonds, or any extensive breakdown of carbohydrate polymers. Dissolution was increased by alcohols and urea, even at high salt concentrations, but was not affected by metabolic inhibitors. Thus, no evidence was found for a dilution-activated lytic enzyme that contributes to envelope breakdown. Cells of H. cutirubrum were stable in 2 m NaCl, but lysis occurred in 2 m KCl or NH4Cl. This lysis did not involve an extensive breakdown of the envelope. No evidence for different sites of Na+, K+, and NH4+ action was obtained from the pattern of release of envelope constituents in different concentrations of these salts. Ultracentrifugation studies showed that adding salts to envelopes that had been dissolved in water led to a nonspecific reaggregation of envelope material. No difference was seen between the effects of KCl and NaCl, except at 3 to 4 m concentrations where KCl caused more aggregation. The preferential effect of Na+ on intact cells is probably due to its ability specifically to prevent leakage rather than to an overall effect on envelope integrity. Images PMID:5883109

Reduced gas accretion on super-Earths and ice giants

NASA Astrophysics Data System (ADS)

Lambrechts, M.; Lega, E.

2017-10-01

A large fraction of giant planets have gaseous envelopes that are limited to about 10% of their total mass budget. Such planets are present in the solar system (Uranus, Neptune) and are frequently observed in short periods around other stars (the so-called super-Earths). In contrast to these observations, theoretical calculations based on the evolution of hydrostatic envelopes argue that such low-mass envelopes cannot be maintained around cores exceeding five Earth masses. Instead, under nominal disk conditions, these planets would acquire massive envelopes through runaway gas accretion within the lifetime of the protoplanetary disk. In this work we show that planetary envelopes are not in hydrostatic balance, which slows down envelope growth. A series of 3D global, radiative hydrodynamical simulations reveal a steady-state gas flow, which enters through the poles and exits in the disk midplane. Gas is pushed through the outer envelope in about ten orbital timescales. In regions of the disk that are not significantly dust-depleted, envelope accretion onto cores of about five Earth masses can get stalled as the gas flow enters the deep interior. Accreted solids sublimate deep in the convective interior, but small opacity-providing grains are trapped in the flow and do not settle, which further prevents rapid envelope accretion. The transition to runaway gas accretion can however be reached when cores grow larger than typical super-Earths, beyond 15 Earth masses, and preferably when disk opacities are below κ = 1 cm2/g. These findings offer an explanation for the typical low-mass envelopes around the cores of super-Earths.

Removal of envelope protein-free retroviral vectors by anion-exchange chromatography to improve product quality.

PubMed

Rodrigues, Teresa; Alves, Ana; Lopes, António; Carrondo, Manuel J T; Alves, Paula M; Cruz, Pedro E

2008-10-01

We have investigated the role of the retroviral lipid bilayer and envelope proteins in the adsorption of retroviral vectors (RVs) to a Fractogel DEAE matrix. Intact RVs and their degradation components (envelope protein-free vectors and solubilized vector components) were adsorbed to this matrix and eluted using a linear gradient. Envelope protein-free RVs (Env(-)) and soluble envelope proteins (gp70) eluted in a significantly lower range of conductivities than intact RVs (Env(+)) (13.7-30 mS/cm for Env(-) and gp70 proteins vs. 47-80 mS/cm for Env(+)). The zeta (zeta)-potential of Env(+) and Env(-) vectors was evaluated showing that envelope proteins define the pI of the viral particles (pI (Env(+)) < 2 versus 3 < pI (Env(-)) < 4) and that Env(+) and Env(-) vectors have similar zeta-potentials within pH 5 and 8. The results presented herein indicate that the adsorption of retroviral particles occurs through multi-point interaction of the envelope proteins with the cationic groups on the chromatographic matrix. The strength of this adsorption is thus dependent on the amount of envelope protein present in the viral lipid bilayer. In conclusion, AEXc enables the separation of gp70 proteins as well as envelope protein-free vectors constituting a significant improvement to the quality of retroviral preparations for gene therapy applications.

Defective plastic infection-control barriers and faulty technique may cause PSP plate contamination used in digital intraoral radiography.

PubMed

Kuperstein, Arthur S

2012-09-01

Fifty-two disinfected photostimulable phosphor (PSP) plates in plastic barrier envelopes were evaluated for contamination following placement in 30 study participants. Forty-four plates were acceptable for use in the study. The risk factor was the abundant oropharyngeal microbial flora and its ability to breach infection-control barrier sheaths. The presence of bacterial colonies on an agar plate was used to determine bacterial contamination and the presence of any growth indicated failure of the barrier envelope. Before clinical placement of the plates, quality review of the PSP plates revealed defects in the integrity of 4 barrier envelopes most likely caused by forceps-related damage or failure to achieve a uniform seal during manufacturing. These defects allowed substantial contamination. Contamination also occurred as a result of failure to extract the PSP plate from the barrier envelope cleanly. Of the 44 barriers with no obvious signs of a defect, 3 produced bacterial growth following culture. The authors concluded that digital sensor sheathed in barrier envelopes remain a potential source of contamination. PSP plates must be disinfected between removal from a contaminated barrier envelope (used in a patient) and placement in a new barrier envelope. In addition, placement into the barrier envelope should ideally be carried out under aseptic conditions. Finally, the integrity of each sealed barrier envelope must be verified visually. Copyright © 2012. Published by Mosby, Inc. All rights reserved.

Targeting of loaded Sendai virus envelopes by covalently attached insulin molecules to virus receptor-depleted cells: fusion-mediated microinjection of ricin A and simian virus 40 DNA.

PubMed

Gitman, A G; Graessmann, A; Loyter, A

1985-11-01

Insulin molecules were covalently attached to detergent-solubilized Sendai virus envelope glycoproteins (HN and F polypeptides) by the use of the crosslinking reagent succinimidyl 4-(p-maleimidophenyl)butyrate (SMPB). Reconstitution of modified viral glycoproteins (carrying covalently attached insulin) together with unmodified viral glycoproteins resulted in the formation of "fusogenic" viral envelopes bearing insulin molecules. Reconstitution of such fusogenic viral envelopes in the presence of ricin A or simian virus 40 (SV40) DNA resulted in the formation of viral envelopes bearing insulin molecules and loaded with ricin A or SV40 DNA. Such viral envelopes were able to bind to hepatoma tissue culture cells (HTCC) from which Sendai virus receptors were removed by treatment with neuraminidase. Incubation of viral envelopes loaded with ricin A with virus receptor-depleted HTCC resulted in fusion-mediated injection of the toxin, as inferred from inhibition of protein synthesis and decrease in cell viability of the microinjected cells. Fusion-mediated injection of SV40 DNA was inferred from the appearance of SV40 tumor antigen in microinjected cells. Binding and fusion of the loaded viral envelopes to neuraminidase-treated HTCC was mediated solely by the virus-associated insulin molecules. Addition of free insulin molecules inhibited binding of the viral envelopes and, consequently, the microinjection of ricin A and SV40 DNA.

Targeting of loaded Sendai virus envelopes by covalently attached insulin molecules to virus receptor-depleted cells: fusion-mediated microinjection of ricin A and simian virus 40 DNA.

PubMed Central

Gitman, A G; Graessmann, A; Loyter, A

1985-01-01

Insulin molecules were covalently attached to detergent-solubilized Sendai virus envelope glycoproteins (HN and F polypeptides) by the use of the crosslinking reagent succinimidyl 4-(p-maleimidophenyl)butyrate (SMPB). Reconstitution of modified viral glycoproteins (carrying covalently attached insulin) together with unmodified viral glycoproteins resulted in the formation of "fusogenic" viral envelopes bearing insulin molecules. Reconstitution of such fusogenic viral envelopes in the presence of ricin A or simian virus 40 (SV40) DNA resulted in the formation of viral envelopes bearing insulin molecules and loaded with ricin A or SV40 DNA. Such viral envelopes were able to bind to hepatoma tissue culture cells (HTCC) from which Sendai virus receptors were removed by treatment with neuraminidase. Incubation of viral envelopes loaded with ricin A with virus receptor-depleted HTCC resulted in fusion-mediated injection of the toxin, as inferred from inhibition of protein synthesis and decrease in cell viability of the microinjected cells. Fusion-mediated injection of SV40 DNA was inferred from the appearance of SV40 tumor antigen in microinjected cells. Binding and fusion of the loaded viral envelopes to neuraminidase-treated HTCC was mediated solely by the virus-associated insulin molecules. Addition of free insulin molecules inhibited binding of the viral envelopes and, consequently, the microinjection of ricin A and SV40 DNA. PMID:2997783

Transduction of Human Primitive Repopulating Hematopoietic Cells With Lentiviral Vectors Pseudotyped With Various Envelope Proteins

PubMed Central

Kim, Yoon-Sang; Wielgosz, Matthew M; Hargrove, Phillip; Kepes, Steven; Gray, John; Persons, Derek A; Nienhuis, Arthur W

2010-01-01

Lentiviral vectors are useful for transducing primitive hematopoietic cells. We examined four envelope proteins for their ability to mediate lentiviral transduction of mobilized human CD34+ peripheral blood cells. Lentiviral particles encoding green fluorescent protein (GFP) were pseudotyped with the vesicular stomatitis virus envelope glycoprotein (VSV-G), the amphotropic (AMPHO) murine leukemia virus envelope protein, the endogenous feline leukemia viral envelope protein or the feline leukemia virus type C envelope protein. Because the relative amount of genome RNA per ml was similar for each pseudotype, we transduced CD34+ cells with a fixed volume of each vector preparation. Following an overnight transduction, CD34+ cells were transplanted into immunodeficient mice which were sacrificed 12 weeks later. The average percentages of engrafted human CD45+ cells in total bone marrow were comparable to that of the control, mock-transduced group (37–45%). Lenti-particles pseudotyped with the VSV-G envelope protein transduced engrafting cells two- to tenfold better than particles pseudotyped with any of the γ-retroviral envelope proteins. There was no correlation between receptor mRNA levels for the γ-retroviral vectors and transduction efficiency of primitive hematopoietic cells. These results support the use of the VSV-G envelope protein for the development of lentiviral producer cell lines for manufacture of clinical-grade vector. PMID:20372106

The Role of Amplitude Envelope in Lexical Tone Perception: Evidence from Cantonese Lexical Tone Discrimination in Adults with Normal Hearing

ERIC Educational Resources Information Center

Zhou, Yining Victor

2012-01-01

Previously published studies on the role of amplitude envelope in lexical tone perception focused on Mandarin only. Amplitude envelope was found to co-vary with fundamental frequency in Mandarin lexical tones, and amplitude envelope alone could cue tone perception in Mandarin which uses primarily tone contour for phonemic tonal contrasts. The…

Gravitational Waves from Accreting Neutron Stars Undergoing Common-envelope Inspiral

NASA Astrophysics Data System (ADS)

Holgado, A. Miguel; Ricker, Paul M.; Huerta, E. A.

2018-04-01

The common-envelope phase is a likely formation channel for close binary systems containing compact objects. Neutron stars in common envelopes accrete at a fraction of the Bondi–Hoyle–Lyttleton accretion rate, since the stellar envelope is inhomogeneous, but they may still be able to accrete at hypercritical rates (though not enough to become black holes). We show that common-envelope systems consisting of a neutron star with a massive primary may be gravitational-wave (GW) sources detectable in the Advanced LIGO band as far away as the Magellanic Clouds. To characterize their evolution, we perform orbital integrations using 1D models of 12 M ⊙ and 20 M ⊙ primaries, considering the effects of density gradient on the accretion onto the NS and spin evolution. From the range of possible accretion rates relevant to common-envelope evolution, we find that these systems may be louder GW sources than low-mass X-ray binaries like Sco X-1, which are currently the target of directed searches for continuous GWs. We also find that their strain amplitude signal may allow for novel constraints on the orbital separation and inspiral timescale in common envelopes when combined with pre-common-envelope electromagnetic observations.

A common pathway for p10 and calyx proteins in progressive stages of polyhedron envelope assembly in AcMNPV-infected Spodoptera frugiperda larvae.

PubMed

Lee, S Y; Poloumienko, A; Belfry, S; Qu, X; Chen, W; MacAfee, N; Morin, B; Lucarotti, C; Krause, M

1996-01-01

The assembly of the polyhedron envelope in baculovirus-infected cells has been the subject of several studies, yet it is still poorly understood. We have used immunogold-labelled antibodies to two baculovirus proteins, p10 and calyx (also referred to as polyhedron envelope protein or PEP), to follow envelope assembly in AcMNPV-infected tissues of Spodoptera frugiperda larvae. We show that, in wild type virus, both proteins colocalize in fibrillar structures and associated electron-dense spacers which progress to encircle the polyhedra, as well as in completed polyhedron envelopes. In cells infected with polyhedrin-negative (PH-) viruses, an unusual proliferation of these spacers was observed suggesting a deregulatory event in the envelope assembly process. Results of Northern and Western blot analysis revealed that synthesis of P10 and calyx mRNA and proteins in PH- AcMNPV is unaffected as compared to wild type virus. Taken together, the observed physical and compositional connection between fibrillar structures, spacers and polyhedron envelopes, as well as the abnormal appearance of the spacers in PH- mutants, provide further evidence in support of a cooperative role of these structures in the assembly of the polyhedron envelope.

26 CFR 1.103-11 - Bonds held by substantial users.

Code of Federal Regulations, 2010 CFR

2010-04-01

... subleases space to a restaurant operator at an annual rental of $25,000 for the operation of a canteen and... by the restaurant operator are more than 5 percent of the respective amounts with respect to the entire facility. Both X and the restaurant operator are substantial users. However, absent special...

Inability of keratinocytes lacking their specific transglutaminase to form cross-linked envelopes: Absence of envelopes as a simple diagnostic test for lamellar ichthyosis

PubMed Central

Jeon, Saewha; Djian, Philippe; Green, Howard

1998-01-01

Epidermal keratinocytes, late in their terminal differentiation, form cross-linked envelopes resistant to ionic detergent and reducing agent. Because the cross-linking process is catalyzed by the keratinocyte transglutaminase, the absence of active transglutaminase should result in failure of the keratinocyte to form a cross-linked envelope. Three keratinocyte strains bearing mutations in the keratinocyte transglutaminase were examined: two contained no detectable transglutaminase mRNA and none contained active enzyme. All three were unable to form cross-linked envelopes, either spontaneously in stratified cultures or upon induction with Ca2+. Although stratum corneum of normal humans and scales from patients with different ichthyotic diseases contain cross-linked envelopes, those from patients with transglutaminase-negative lamellar ichthyosis do not. Therefore, the disease due to the absence of transglutaminase may be readily distinguished from other ichthyotic diseases by a simple test for cross-linked envelopes. PMID:9435253

Structure and Chemical Composition of Prospheroplast Envelopes of Saccharomyces cerevisiae and Hansenula anomala

PubMed Central

Darling, Sven; Theilade, Jørgen; Birch-Andersen, Aksel

1972-01-01

Cells of Saccharomyces cerevisiae and Hansenula anomala were digested with snail enzyme under conditions yielding prospheroplasts. Surrounding envelopes were isolated after lysis of prospheroplasts in distilled water. The envelope material was embedded and sectioned for electron microscopy, and thin, hollow structures still retaining the elongated form of the original cells were seen. The envelopes were of low electron density in sections stained with uranyl magnesium acetate and lead citrate, but were more electron-dense when stained with phosphotungstic acid. Shadowed preparations of prospheroplast envelopes revealed structures resembling ghosts. These “ghosts” were similar to the original cells in form and size but seemed to be very thin. Varying numbers of anular structures (bud scars) were found on them. Chemical analyses of the envelope indicated that an alkali-soluble glucan was a major constituent. The results show that the prospheroplast envelope is part of the original cell wall of the yeast and is located in close apposition to the cytoplasmic membrane. Images PMID:4552997

Synthesis and transfer of galactolipids in the chloroplast envelope membranes of Arabidopsis thaliana.

PubMed

Kelly, Amélie A; Kalisch, Barbara; Hölzl, Georg; Schulze, Sandra; Thiele, Juliane; Melzer, Michael; Roston, Rebecca L; Benning, Christoph; Dörmann, Peter

2016-09-20

Galactolipids [monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG)] are the hallmark lipids of photosynthetic membranes. The galactolipid synthases MGD1 and DGD1 catalyze consecutive galactosyltransfer reactions but localize to the inner and outer chloroplast envelopes, respectively, necessitating intermembrane lipid transfer. Here we show that the N-terminal sequence of DGD1 (NDGD1) is required for galactolipid transfer between the envelopes. Different diglycosyllipid synthases (DGD1, DGD2, and Chloroflexus glucosyltransferase) were introduced into the dgd1-1 mutant of Arabidopsis in fusion with N-terminal extensions (NDGD1 and NDGD2) targeting to the outer envelope. Reconstruction of DGDG synthesis in the outer envelope membrane was observed only with diglycosyllipid synthase fusion proteins carrying NDGD1, indicating that NDGD1 enables galactolipid translocation between envelopes. NDGD1 binds to phosphatidic acid (PA) in membranes and mediates PA-dependent membrane fusion in vitro. These findings provide a mechanism for the sorting and selective channeling of lipid precursors between the galactolipid pools of the two envelope membranes.

Single-round selection yields a unique retroviral envelope utilizing GPR172A as its host receptor.

PubMed

Mazari, Peter M; Linder-Basso, Daniela; Sarangi, Anindita; Chang, Yehchung; Roth, Monica J

2009-04-07

The recognition by a viral envelope of its cognate host-cell receptor is the initial critical step in defining the viral host-range and tissue specificity. This study combines a single-round of selection of a random envelope library with a parallel cDNA screen for receptor function to identify a distinct retroviral envelope/receptor pair. The 11-aa targeting domain of the modified feline leukemia virus envelope consists of a constrained peptide. Critical to the binding of the constrained peptide envelope to its cellular receptor are a pair of internal cysteines and an essential Trp required for maintenance of titers >10(5) lacZ staining units per milliliter. The receptor used for viral entry is the human GPR172A protein, a G-protein-coupled receptor isolated from osteosarcoma cells. The ability to generate unique envelopes capable of using tissue- or disease-specific receptors marks an advance in the development of efficient gene-therapy vectors.

Dynamic push-pull characteristics at three hand-reach envelopes: applications for the workplace.

PubMed

Calé-Benzoor, Maya; Dickstein, Ruth; Arnon, Michal; Ayalon, Moshe

2016-01-01

Pushing and pulling are common tasks in the workplace. Overexertion injuries related to manual pushing and pulling are often observed, and therefore the understanding of work capacity is important for efficient and safe workstation design. The purpose of the present study was to describe workloads obtained during different reach envelopes during a seated push-pull task. Forty-five women performed an isokinetic push-pull sequence at two velocities. Strength, work and agonist/antagonist muscle ratio were calculated for the full range of motion (ROM). We then divided the ROM into three reach envelopes - neutral, medium, and maximum reach. The work capacity for each direction was determined and the reach envelope work data were compared. Push capability was best at medium reach envelope and pulling was best at maximum reach envelope. Push/pull strength ratio was approximately 1. A recommendation was made to avoid strenuous push-pull tasks at neutral reach envelopes. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Management of Lower Extremity Long-bone Fractures in Spinal Cord Injury Patients.

PubMed

Schulte, Leah M; Scully, Ryan D; Kappa, Jason E

2017-09-01

The AO classification system, used as a guide for modern fracture care and fixation, follows a basic philosophy of care that emphasizes early mobility and return to function. Lower extremity long-bone fractures in patients with spinal cord injury often are pathologic injuries that present unique challenges, to which the AO principles may not be entirely applicable. Optimal treatment achieves healing without affecting the functional level of the patient. These injuries often result from low-energy mechanisms in nonambulatory patients with osteopenic bone and a thin, insensate soft-tissue envelope. The complication rate can be high, and the outcomes can be catastrophic without proper care. Satisfactory results can be obtained through various methods of immobilization. Less frequently, internal fixation is applied. In certain cases, after discussion with the patient, amputation may be suitable. Prevention strategies aim to minimize bone loss and muscle atrophy.

Numerical Solution of the Kzk Equation for Pulsed Finite Amplitude Sound Beams in Thermoviscous Fluids

NASA Astrophysics Data System (ADS)

Lee, Yang-Sub

A time-domain numerical algorithm for solving the KZK (Khokhlov-Zabolotskaya-Kuznetsov) nonlinear parabolic wave equation is developed for pulsed, axisymmetric, finite amplitude sound beams in thermoviscous fluids. The KZK equation accounts for the combined effects of diffraction, absorption, and nonlinearity at the same order of approximation. The accuracy of the algorithm is established via comparison with analytical solutions for several limiting cases, and with numerical results obtained from a widely used algorithm for solving the KZK equation in the frequency domain. The time domain algorithm is used to investigate waveform distortion and shock formation in directive sound beams radiated by pulsed circular piston sources. New results include predictions for the entire process of self-demodulation, and for the effect of frequency modulation on pulse envelope distortion. Numerical results are compared with measurements, and focused sources are investigated briefly.

Nonlinear dynamics near the stability margin in rotating pipe flow

NASA Technical Reports Server (NTRS)

Yang, Z.; Leibovich, S.

1991-01-01

The nonlinear evolution of marginally unstable wave packets in rotating pipe flow is studied. These flows depend on two control parameters, which may be taken to be the axial Reynolds number R and a Rossby number, q. Marginal stability is realized on a curve in the (R, q)-plane, and the entire marginal stability boundary is explored. As the flow passes through any point on the marginal stability curve, it undergoes a supercritical Hopf bifurcation and the steady base flow is replaced by a traveling wave. The envelope of the wave system is governed by a complex Ginzburg-Landau equation. The Ginzburg-Landau equation admits Stokes waves, which correspond to standing modulations of the linear traveling wavetrain, as well as traveling wave modulations of the linear wavetrain. Bands of wavenumbers are identified in which the nonlinear modulated waves are subject to a sideband instability.

Soft X-Ray Tomography Reveals Gradual Chromatin Compaction and Reorganization during Neurogenesis In Vivo

DOE PAGES

Le Gros, Mark A.; Clowney, E. Josephine; Magklara, Angeliki; ...

2016-11-15

The realization that nuclear distribution of DNA, RNA, and proteins differs between cell types and developmental stages suggests that nuclear organization serves regulatory functions. Understanding the logic of nuclear architecture and how it contributes to differentiation and cell fate commitment remains challenging. Here, we use soft X-ray tomography (SXT) to image chromatin organization, distribution, and biophysical properties during neurogenesis in vivo. Our analyses reveal that chromatin with similar biophysical properties forms an elaborate connected network throughout the entire nucleus. Although this interconnectivity is present in every developmental stage, differentiation proceeds with concomitant increase in chromatin compaction and re-distribution of condensed chromatinmore » toward the nuclear core. HP1β, but not nucleosome spacing or phasing, regulates chromatin rearrangements because it governs both the compaction of chromatin and its interactions with the nuclear envelope. Our experiments introduce SXT as a powerful imaging technology for nuclear architecture.« less

Autophagy in adipose tissue biology.

PubMed

Zhang, Yong; Zeng, Xiangang; Jin, Shengkan

2012-12-01

Obesity, which predisposes individuals to type II diabetes and cardiovascular diseases, results from accumulation of white adipose tissue (WAT). WAT comprises mainly white adipocytes that have a unique cellular structure in which almost the entire intracellular space is occupied by one single lipid droplet. The cytoplasm envelopes this lipid droplet and occupies negligible space. Differentiation of WAT, or adipogenesis, requires dramatic cytoplasmic reorganization, including a dynamic change in mitochondrial mass. Autophagy is a major cytoplasmic degradation pathway and a primary pathway for mitochondrial degradation. Recent studies indicate that autophagy is implicated in adipogenesis. In this review, we summarize our current knowledge on autophagy in adipose tissue biology, with the emphasis on its role in mitochondrial degradation. Adipose tissue is a central component for whole-body energy homeostasis regulation. Advancement in this research area may provide novel venues for the intervention of obesity and obesity related diseases. Copyright © 2012 Elsevier Ltd. All rights reserved.

0.5-keV Soft X-ray attosecond continua

PubMed Central

Teichmann, S. M.; Silva, F.; Cousin, S. L.; Hemmer, M.; Biegert, J.

2016-01-01

Attosecond light pulses in the extreme ultraviolet have drawn a great deal of attention due to their ability to interrogate electronic dynamics in real time. Nevertheless, to follow charge dynamics and excitations in materials, element selectivity is a prerequisite, which demands such pulses in the soft X-ray region, above 200 eV, to simultaneously cover several fundamental absorption edges of the constituents of the materials. Here, we experimentally demonstrate the exploitation of a transient phase matching regime to generate carrier envelope controlled soft X-ray supercontinua with pulse energies up to 2.9±0.1 pJ and a flux of (7.3±0.1) × 107 photons per second across the entire water window and attosecond pulses with 13 as transform limit. Our results herald attosecond science at the fundamental absorption edges of matter by bridging the gap between ultrafast temporal resolution and element specific probing. PMID:27167525

Convective instabilities in SN 1987A

NASA Technical Reports Server (NTRS)

Benz, Willy; Thielemann, Friedrich-Karl

1990-01-01

Following Bandiera (1984), it is shown that the relevant criterion to determine the stability of a blast wave, propagating through the layers of a massive star in a supernova explosion, is the Schwarzschild (or Ledoux) criterion rather than the Rayleigh-Taylor criterion. Both criteria coincide only in the incompressible limit. Results of a linear stability analysis are presented for a one-dimensional (spherical) explosion in a realistic model for the progenitor of SN 1987A. When applying the Schwarzschild criterion, unstable regions get extended considerably. Convection is found to develop behind the shock, with a characteristic growth rate corresponding to a time scale much smaller than the shock traversal time. This ensures that efficient mixing will take place. Since the entire ejected mass is found to be convectively unstable, Ni can be transported outward, even into the hydrogen envelope, while hydrogen can be mixed deep into the helium core.

Preliminary research on overmoded high-power millimeter-wave Cerenkov generator with dual-cavity reflector in low guiding magnetic field

NASA Astrophysics Data System (ADS)

Ye, Hu; Chen, Changhua; Ning, Hui; Tan, Weibing; Teng, Yan; Shi, Yanchao; Wu, Ping; Song, Zhimin; Cao, Yibing; Du, Zhaoyu

2015-12-01

This paper presents preliminary research on a V-band overmoded Cerenkov generator with dual-cavity reflector operating in a low guiding magnetic field. It is found that the fluctuation of the electron envelope in the low guiding magnetic field can be predicted using an equivalent coaxial model of a foilless diode, and a dual-cavity reflector based on the model matching method can provide strong reflection at the front end of the overmoded structures so that any microwave power that leaks into the diode region can be effectively suppressed. Numerical simulations indicate that the control of the beam envelope and the use of the dual-cavity reflector ease generator operation in the low guiding magnetic field. In the experimental research, the fluctuation of the annular electron beam with the outer radius of 7.5 mm measures approximately 0.7 mm, which is in good agreement with the theoretical results. The disturbance caused by power leaking from the overmoded slow wave structure is eliminated by the dual-cavity reflector. With accurate fabrication and assembly processes, an operating frequency of 61.6 GHz is attained by the fifth harmonic heterodyne method, and the output power is measured to be approximately 123 MW by the far-field measurement method at a diode voltage of 445 kV, a beam current of 4.45 kA, and under a guiding magnetic field of 1.45 T. The output mode is measured using an array of neon flash bulbs, and the pulse shortening phenomenon is both observed and analyzed.

On Helium-Dominated Stellar Evolution: The Mysterious Role of the O(He)-Type Stars

NASA Technical Reports Server (NTRS)

Reindl, N.; Rauch, T.; Werner, K.; Kruk, J. W.; Todt, H.

2014-01-01

Context. About a quarter of all post-asymptotic giant branch (AGB) stars are hydrogen-deficient. Stellar evolutionary models explain the carbon-dominated H-deficient stars by a (very) late thermal pulse scenario where the hydrogen-rich envelope is mixed with the helium-rich intershell layer. Depending on the particular time at which the final flash occurs, the entire hydrogen envelope may be burned. In contrast, helium-dominated post-AGB stars and their evolution are not yet understood. Aims. A small group of very hot, helium-dominated stars is formed by O(He)-type stars. A precise analysis of their photospheric abundances will establish constraints to their evolution. Methods. We performed a detailed spectral analysis of ultraviolet and optical spectra of four O(He) stars by means of state-of-the-art non-LTE model-atmosphere techniques. Results. We determined effective temperatures, surface gravities, and the abundances of H, He, C, N, O, F, Ne, Si, P, S, Ar, and Fe. By deriving upper limits for the mass-loss rates of the O(He) stars, we found that they do not exhibit enhanced mass-loss. The comparison with evolutionary models shows that the status of the O(He) stars remains uncertain. Their abundances match predictions of a double helium white dwarf (WD) merger scenario, suggesting that they might be the progeny of the compact and of the luminous helium-rich sdO-type stars. The existence of planetary nebulae that do not show helium enrichment around every other O(He) star precludes a merger origin for these stars. These stars must have formed in a different way, for instance via enhanced mass-loss during their post-AGB evolution or a merger within a common-envelope (CE) of a CO-WD and a red giant or AGB star. Conclusions. A helium-dominated stellar evolutionary sequence exists that may be fed by different types of mergers or CE scenarios. It appears likely that all these pass through the O(He) phase just before they become WDs.

Comment on Sub-15 nm Hard X-Ray Focusing with a New Total-Reflection Zone Plate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Specht, Eliot D

2011-01-01

Takano et al. report the focusing of 10-keV X-rays to a size of 14.4 nm using a total-reflection zone plate (TRZP). This focal size is at the diffraction limit for the optic's aperture. This would be a noteworthy result, since the TRZP was fabricated using conventional lithography techniques. Alternative nanofocusing optics require more demanding fabrication methods. However, as I will discuss in this Comment, the intensity distribution presented by Takano et al. (Fig. 4 of ref. 1) is more consistent with the random speckle pattern produced by the scattering of a coherent incident beam by a distorted optic than withmore » a diffraction-limited focus. When interpreted in this manner, the true focal spot size is {approx}70 nm: 5 times the diffraction limit. When a coherent photon beam illuminates an optic containing randomly distributed regions which introduce different phase shifts, the scattered diffraction pattern consists of a speckle pattern. Each speckle will be diffraction-limited: the peak width of a single speckle depends entirely on the source coherence and gives no information about the optic. The envelope of the speckle distribution corresponds to the focal spot which would be observed using incoherent illumination. The width of this envelope is due to the finite size of the coherently-diffracting domains produced by slope and position errors in the optic. The focal intensity distribution in Fig. 4 of ref. 1 indeed contains a diffraction-limited peak, but this peak contains only a fraction of the power in the focused, and forms part of a distribution of sharp peaks with an envelope {approx}70 nm in width, just as expected for a speckle pattern. At the 4mm focal distance, the 70 nm width corresponds to a slope error of 18 {micro}rad. To reach the 14 nm diffraction limit, the slope error must be reduced to 3 {micro}rad. Takano et al. have identified a likely source of this error: warping due to stress as a result of zone deposition. It will be interesting to see whether the use of a more rigid substrate gives improved results.« less

Modeling technical efficiency of inshore fishery using data envelopment analysis

NASA Astrophysics Data System (ADS)

Rahman, Rahayu; Zahid, Zalina; Khairi, Siti Shaliza Mohd; Hussin, Siti Aida Sheikh

2016-10-01

Fishery industry contributes significantly to the economy of Malaysia. This study utilized Data Envelopment Analysis application in estimating the technical efficiency of fishery in Terengganu, a state on the eastern coast of Peninsular Malaysia, based on multiple output, i.e. total fish landing and income of fishermen with six inputs, i.e. engine power, vessel size, number of trips, number of workers, cost and operation distance. The data were collected by survey conducted between November and December 2014. The decision making units (DMUs) involved 100 fishermen from 10 fishery areas. The result showed that the technical efficiency in Season I (dry season) and Season II (rainy season) were 90.2% and 66.7% respectively. About 27% of the fishermen were rated to be efficient during Season I, meanwhile only 13% of the fishermen achieved full efficiency 100% during Season II. The results also found out that there was a significance difference in the efficiency performance between the fishery areas.

Measuring the efficiency of zakat collection process using data envelopment analysis

NASA Astrophysics Data System (ADS)

Hamzah, Ahmad Aizuddin; Krishnan, Anath Rau

2016-10-01

It is really necessary for each zakat institution in the nation to timely measure and understand their efficiency in collecting zakat for the sake of continuous betterment. Pusat Zakat Sabah, Malaysia which has kicked off its operation in early of 2007, is not excused from this obligation as well. However, measuring the collection efficiency is not a very easy task as it usually incorporates the consideration of multiple inputs or/and outputs. This paper sequentially employed three data envelopment analysis models, namely Charnes-Cooper-Rhodes (CCR) primal model, CCR dual model, and slack based model to quantitatively evaluate the efficiency of zakat collection in Sabah across the year of 2007 up to 2015 by treating each year as a decision making unit. The three models were developed based on two inputs (i.e. number of zakat branches and number of staff) and one output (i.e. total collection). The causes for not achieving efficiency and the suggestions on how the efficiency in each year could have been improved were disclosed.

Correlation-based discrimination between cardiac tissue and blood for segmentation of 3D echocardiographic images

NASA Astrophysics Data System (ADS)

Saris, Anne E. C. M.; Nillesen, Maartje M.; Lopata, Richard G. P.; de Korte, Chris L.

2013-03-01

Automated segmentation of 3D echocardiographic images in patients with congenital heart disease is challenging, because the boundary between blood and cardiac tissue is poorly defined in some regions. Cardiologists mentally incorporate movement of the heart, using temporal coherence of structures to resolve ambiguities. Therefore, we investigated the merit of temporal cross-correlation for automated segmentation over the entire cardiac cycle. Optimal settings for maximum cross-correlation (MCC) calculation, based on a 3D cross-correlation based displacement estimation algorithm, were determined to obtain the best contrast between blood and myocardial tissue over the entire cardiac cycle. Resulting envelope-based as well as RF-based MCC values were used as additional external force in a deformable model approach, to segment the left-ventricular cavity in entire systolic phase. MCC values were tested against, and combined with, adaptive filtered, demodulated RF-data. Segmentation results were compared with manually segmented volumes using a 3D Dice Similarity Index (3DSI). Results in 3D pediatric echocardiographic images sequences (n = 4) demonstrate that incorporation of temporal information improves segmentation. The use of MCC values, either alone or in combination with adaptive filtered, demodulated RF-data, resulted in an increase of the 3DSI in 75% of the cases (average 3DSI increase: 0.71 to 0.82). Results might be further improved by optimizing MCC-contrast locally, in regions with low blood-tissue contrast. Reducing underestimation of the endocardial volume due to MCC processing scheme (choice of window size) and consequential border-misalignment, could also lead to more accurate segmentations. Furthermore, increasing the frame rate will also increase MCC-contrast and thus improve segmentation.

N1N8-bis(gamma-glutamyl)spermidine cross-linking in epidermal-cell envelopes. Comparison of cross-link levels in normal and psoriatic cell envelopes.

PubMed Central

Martinet, N; Beninati, S; Nigra, T P; Folk, J E

1990-01-01

N1N8-Bis(gamma-glutamyl)spermidine was found in exhaustive proteolytic digests of isolated cell envelopes from human epidermis at levels comparable with those of epsilon-(gamma-glutamyl)lysine. Significantly higher than normal amounts of these compounds, particularly the bis(gamma-glutamyl)polyamine, were observed in envelopes from afflicted areas (scales) of psoriatic patients. These findings support the notions that N1N8-bis(gamma-glutamyl)spermidine, like epsilon-(gamma-glutamyl)lysine, functions in cell envelopes as an enzyme-generated protein cross-link and stabilizing force and that individuals with the chronic, recurrent skin disease, psoriasis, exhibit in involved epidermis abnormal cell-envelope-protein cross-linking. PMID:2241917

A Spectral Algorithm for Envelope Reduction of Sparse Matrices

NASA Technical Reports Server (NTRS)

Barnard, Stephen T.; Pothen, Alex; Simon, Horst D.

1993-01-01

The problem of reordering a sparse symmetric matrix to reduce its envelope size is considered. A new spectral algorithm for computing an envelope-reducing reordering is obtained by associating a Laplacian matrix with the given matrix and then sorting the components of a specified eigenvector of the Laplacian. This Laplacian eigenvector solves a continuous relaxation of a discrete problem related to envelope minimization called the minimum 2-sum problem. The permutation vector computed by the spectral algorithm is a closest permutation vector to the specified Laplacian eigenvector. Numerical results show that the new reordering algorithm usually computes smaller envelope sizes than those obtained from the current standard algorithms such as Gibbs-Poole-Stockmeyer (GPS) or SPARSPAK reverse Cuthill-McKee (RCM), in some cases reducing the envelope by more than a factor of two.

Broadband midinfrared frequency comb with tooth scanning

NASA Astrophysics Data System (ADS)

Lee, Kevin F.; Masłowski, P.; Mills, A.; Mohr, C.; Jiang, Jie; Schunemann, Peter G.; Fermann, M. E.

2015-03-01

Frequency combs are a massively parallel source of extremely accurate optical frequencies. Frequency combs generally operate at the visible or near-infrared wavelengths, but fundamental molecular vibrations occur at midinfrared wavelengths. We demonstrate an optically-referenced, broadband midinfrared frequency comb based on a doublyresonant optical parametric oscillator (OPO). By tuning the wavelength of the reference laser, the comb line frequencies are tuned as well. By scanning the reference wavelength, any frequency can be accessed, not just the frequencies of the base comb. Combined with our comb-resolving Fourier transform spectrometer, we can measure 200 wavenumber wide broadband absorption spectra with 200 kHz linewidth comb teeth. Our OPO is pumped by an amplified Tm fiber frequency comb, with phase-locked carrier envelope offset frequency, and repetition rate fixed by phase-locking a frequency comb line to a narrow linewidth diode laser at a telecom channel. The frequency comb is referenced to GPS by long-term stabilization of the repetition rate to a selected value using the temperature of the reference laser as the control. The resulting pump comb is about 3W of 100 fs pulses at 418 MHz repetition rate at 1950 nm. Part of the comb is used for supercontinuum generation for frequency stabilization, and the rest pumps an orientation-patterned gallium arsenide (OP-GaAs) crystal in a doubly-resonant optical parametric oscillator cavity, yielding collinear signal and idler beams from about 3 to 5.5 μm. We verify comb scanning by resolving the 200 MHz wide absorption lines of the entire fundamental CO vibrational manifold at 11 Torr pressure.

Integrated vehicle control and guidance systems in unmanned ground vehicles for commercial applications

NASA Astrophysics Data System (ADS)

Kenyon, Chase H.

1995-01-01

While there is a lot of recent development in the entire IVHS field, very few have had the opportunity to combine the many areas of development into a single integrated `intelligent' unmanned vehicle. One of our systems was developed specifically to serve a major automobile manufacturer's need for an automated vehicle chassis durability test facility. Due to the severity of the road surface human drivers could not be used. A totally automated robotic vehicle driver and guidance system was necessary. In order to deliver fixed price commercial projects now, it was apparent system and component costs were of paramount importance. Cyplex has developed a robust, cost effective single wire guidance system. This system has inherent advantages in system simplicity. Multi-signal (per vehicle lane) systems complicate path planning and layout when multiple lanes and lane changes are required, as on actual highways. The system has demonstrated high enough immunity to rain and light snow cover that normal safety reductions in speed are adequate to stay within the required system performance envelope. This system and it's antenna interface have shown the ability to guide the vehicle at slow speeds (10 MPH) with a tracking repeatability of plus or minus 1/8 of an inch. The basic guide and antenna system has been tested at speeds up to 80 mph. The system has inherently superior abilities for lane changes and precision vehicle placement. The operation of this system will be described and the impact of a system that is commercially viable now for highway and off road use will be discussed.

Project CHECO Southeast Asia Report. BUFFALO HUNTER 1970 - 1972

DTIC Science & Technology

1973-07-24

era, however, the drone’s use was no longer a secret. This report examines the entire BUFFALO HUNTER operation -- management , targeting, drone capabilities, mission planning and execution, and operational results.

Diclofenac Transdermal Patch

MedlinePlus

... will be applying the patch. Cut open the envelope containing the patches, cutting on the dotted line ... it. Pull apart the zipper seal on the envelope and remove one patch. Reseal the envelope by ...

Behaviour of the vitelline envelope in Bufo arenarum oocytes matured in vitro in blockade to polyspermy.

PubMed

Oterino, J; Sánchez Toranzo, G; Zelarayán, L; Ajmat, M T; Bonilla, F; Bühler, M I

2006-05-01

During activation of amphibian eggs, cortical granule exocytosis causes elaborate ultrastructural changes in the vitelline envelope. These changes involve modifications in the structure of the vitelline envelope and formation of a fertilization envelope (FE) that can no longer be penetrated by sperm. In Bufo arenarum, as the egg traverses the oviduct, the vitelline envelope is altered by a trypsin-like protease secreted by the oviduct, which induces an increased susceptibility of the vitelline envelope to sperm lysins. Full-grown oocytes of B. arenarum, matured in vitro by progesterone, are polyspermic, although cortical granule exocytosis seems to occur within a normal chronological sequence. These oocytes can be fertilized with or without trypsin treatment, suggesting that the vitelline envelope is totally sperm-permeable. Vitelline envelopes without trypsin treatment cannot retain either gp90 or gp96. This suggests that these glycoproteins are involved in the block to polyspermy and that trypsin treatment of matured in vitro oocytes before insemination is necessary to enable vitelline envelopes to block polyspermy. The loss of the binding capacity in vitelline envelopes isolated from B. arenarum oocytes matured in vitro with trypsin treatment and activated by electric shock suggests that previous trypsin treatment is a necessary step for sperm block to occur. When in vitro matured oocytes were incubated with the product of cortical granules obtained from in vitro matured oocytes (vCGP), vitelline envelopes with trypsin treatment were able to block sperm entry. These oocytes exhibited the characteristic signs of activation. These results support the idea that B. arenarum oocytes can be activated by external stimuli and suggest the presence of unknown oocyte surface receptors linked to the activation machinery in response to fertilization. Electrophoretic profiles obtained by SDS-PAGE of solubilized vitelline envelopes from oocytes matured in vitro revealed the conversion of gp40 (in vitro matured oocytes, without trypsin treatment) to gp38 (ascribable to trypsin activity or cortical granule product activity, CGP) and the conversion of gp70 to gp68 (ascribable to trypsin activity plus CGP activity). Taking into account that only the vitelline envelopes of in vitro matured oocytes with trypsin treatment and activated can block sperm entry, we may suggest that the conversion of gp70 to gp68 is related to the changes associated with sperm binding.

Do postage stamps versus pre-paid envelopes increase responses to patient mail surveys? A randomised controlled trial.

PubMed

Lavelle, Katrina; Todd, Chris; Campbell, Malcolm

2008-05-28

Studies largely from the market research field suggest that the inclusion of a stamped addressed envelope, rather than a pre-paid business reply, increases the response rate to mail surveys. The evidence that this is also the case regarding patient mail surveys is limited. The aim of this study is to investigate whether stamped addressed envelopes increase response rates to patient mail surveys compared to pre-paid business reply envelopes and compare the relative costs. A sample of 477 initial non-responders to a mail survey of patients attending breast clinics in Greater Manchester between 1/10/2002 - 31/7/2003 were entered into the trial: 239 were randomly allocated to receive a stamped envelope and 238 to receive a pre-paid envelope in with their reminder surveys. Overall cost and per item returned were calculated. The response to the stamped envelope group was 31.8% (95% CI: 25.9% - 37.7%) compared to 26.9% (21.3% - 32.5%) for the pre-paid group. The difference (4.9% 95% CI: -3.3% - 13.1%) is not significant at alpha = 0.05 (chi2 = 1.39; 2 tailed test, d.f. = 1; P = 0.239). The stamped envelopes were cheaper in terms of cost per returned item (1.20 pounds) than the pre-paid envelopes (1.67 pounds). However if the set up cost for the licence to use the pre-paid service is excluded, the cost of the stamped envelopes is more expensive than pre-paid returns (1.20 pounds versus 0.73 pounds). Compared with pre-paid business replies, stamped envelopes did not produce a statistically significant increase in response rate to this patient survey. However, the response gain of the stamped strategy (4.9%) is similar to that demonstrated in a Cochrane review (5.3%) of strategies to increase response to general mail surveys. Further studies and meta analyses of patient responses to mail surveys via stamped versus pre-paid envelopes are needed with sufficient power to detect response gains of this magnitude in a patient population.

The coolest extremely low-mass white dwarfs

NASA Astrophysics Data System (ADS)

Calcaferro, Leila M.; Althaus, Leandro G.; Córsico, Alejandro H.

2018-06-01

Context. Extremely low-mass white dwarf (ELM WD; M⋆ ≲ 0.18-0.20 M⊙) stars are thought to be formed in binary systems via stable or unstable mass transfer. Although stable mass transfer predicts the formation of ELM WDs with thick hydrogen (H) envelopes that are characterized by dominant residual nuclear burning along the cooling branch, the formation of ELM WDs with thinner H envelopes from unstable mass loss cannot be discarded. Aims: We compute new evolutionary sequences for helium (He) core WD stars with thin H envelopes with the main aim of assessing the lowest Teff that could be reached by this type of stars. Methods: We generate a new grid of evolutionary sequences of He-core WD stars with thin H envelopes in the mass range from 0.1554 to 0.2025 M⊙, and assess the changes in both the cooling times and surface gravity induced by a reduction of the H envelope. We also determine, taking into account the predictions of progenitor evolution, the lowest Teff reached by the resulting ELM WDs. Results: We find that a slight reduction in the H envelope yields a significant increase in the cooling rate of ELM WDs. Because of this, ELM WDs with thin H envelopes could cool down to 2500 K, in contrast to their canonical counterparts that cool down to 7000 K. In addition, we find that a reduction of the thickness of the H envelope markedly increases the surface gravity (g) of these stars. Conclusions: If ELM WDs are formed with thin H envelopes, they could be detected at very low Teff. The detection of such cool ELM WDs would be indicative that they were formed with thin H envelopes, thus opening the possibility of placing constraints on the possible mechanisms of formation of this type of star. Last but not least, the increase in g due to the reduction of the H envelope leads to consequences in the spectroscopic determinations of these stars.

Characterization of the radiation environment at the UNLV accelerator facility during operation of the Varian M6 linac

NASA Astrophysics Data System (ADS)

Hodges, M.; Barzilov, A.; Chen, Y.; Lowe, D.

2016-10-01

The bremsstrahlung photon flux from the UNLV particle accelerator (Varian M6 model) was determined using MCNP5 code for 3 MeV and 6 MeV incident electrons. Human biological equivalent dose rates due to accelerator operation were evaluated using the photon flux with the flux-to-dose conversion factors. Dose rates were computed for the accelerator facility for M6 linac use under different operating conditions. The results showed that the use of collimators and linac internal shielding significantly reduced the dose rates throughout the facility. It was shown that the walls of the facility, in addition to the earthen berm enveloping the building, provide equivalent shielding to reduce dose rates outside to below the 2 mrem/h limit.

40 CFR 190.10 - Standards for normal operations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Standards for the Uranium Fuel Cycle § 190.10 Standards for normal operations. Operations covered by this... radioactive materials, radon and its daughters excepted, to the general environment from uranium fuel cycle... the general environment from the entire uranium fuel cycle, per gigawatt-year of electrical energy...

40 CFR 426.121 - Specialized definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Incandescent Lamp Envelope... portion of the “furnace pull” associated with the fraction of finished incandescent lamp envelopes which... finished incandescent lamp envelopes which is frosted. ...

40 CFR 426.121 - Specialized definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Incandescent Lamp Envelope... portion of the “furnace pull” associated with the fraction of finished incandescent lamp envelopes which... finished incandescent lamp envelopes which is frosted. ...

40 CFR 426.121 - Specialized definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Incandescent Lamp Envelope... portion of the “furnace pull” associated with the fraction of finished incandescent lamp envelopes which... finished incandescent lamp envelopes which is frosted. ...

Full waveform inversion using envelope-based global correlation norm

NASA Astrophysics Data System (ADS)

Oh, Ju-Won; Alkhalifah, Tariq

2018-05-01

To increase the feasibility of full waveform inversion on real data, we suggest a new objective function, which is defined as the global correlation of the envelopes of modelled and observed data. The envelope-based global correlation norm has the advantage of the envelope inversion that generates artificial low-frequency information, which provides the possibility to recover long-wavelength structure in an early stage. In addition, the envelope-based global correlation norm maintains the advantage of the global correlation norm, which reduces the sensitivity of the misfit to amplitude errors so that the performance of inversion on real data can be enhanced when the exact source wavelet is not available and more complex physics are ignored. Through the synthetic example for 2-D SEG/EAGE overthrust model with inaccurate source wavelet, we compare the performance of four different approaches, which are the least-squares waveform inversion, least-squares envelope inversion, global correlation norm and envelope-based global correlation norm. Finally, we apply the envelope-based global correlation norm on the 3-D Ocean Bottom Cable (OBC) data from the North Sea. The envelope-based global correlation norm captures the strong reflections from the high-velocity caprock and generates artificial low-frequency reflection energy that helps us recover long-wavelength structure of the model domain in the early stages. From this long-wavelength model, the conventional global correlation norm is sequentially applied to invert for higher-resolution features of the model.

Envelope statistics of self-motion signals experienced by human subjects during everyday activities: Implications for vestibular processing.

PubMed

Carriot, Jérome; Jamali, Mohsen; Cullen, Kathleen E; Chacron, Maurice J

2017-01-01

There is accumulating evidence that the brain's neural coding strategies are constrained by natural stimulus statistics. Here we investigated the statistics of the time varying envelope (i.e. a second-order stimulus attribute that is related to variance) of rotational and translational self-motion signals experienced by human subjects during everyday activities. We found that envelopes can reach large values across all six motion dimensions (~450 deg/s for rotations and ~4 G for translations). Unlike results obtained in other sensory modalities, the spectral power of envelope signals decreased slowly for low (< 2 Hz) and more sharply for high (>2 Hz) temporal frequencies and thus was not well-fit by a power law. We next compared the spectral properties of envelope signals resulting from active and passive self-motion, as well as those resulting from signals obtained when the subject is absent (i.e. external stimuli). Our data suggest that different mechanisms underlie deviation from scale invariance in rotational and translational self-motion envelopes. Specifically, active self-motion and filtering by the human body cause deviation from scale invariance primarily for translational and rotational envelope signals, respectively. Finally, we used well-established models in order to predict the responses of peripheral vestibular afferents to natural envelope stimuli. We found that irregular afferents responded more strongly to envelopes than their regular counterparts. Our findings have important consequences for understanding the coding strategies used by the vestibular system to process natural second-order self-motion signals.

10 CFR 36.67 - Entering and leaving the radiation room.

Code of Federal Regulations, 2011 CFR

2011-01-01

... radiation room of a panoramic irradiator after an irradiation, the irradiator operator shall use a survey... irradiation, the irradiator operator shall: (1) Visually inspect the entire radiation room to verify that no...

10 CFR 36.67 - Entering and leaving the radiation room.

Code of Federal Regulations, 2010 CFR

2010-01-01

... radiation room of a panoramic irradiator after an irradiation, the irradiator operator shall use a survey... irradiation, the irradiator operator shall: (1) Visually inspect the entire radiation room to verify that no...

10 CFR 36.67 - Entering and leaving the radiation room.

Code of Federal Regulations, 2014 CFR

2014-01-01

... radiation room of a panoramic irradiator after an irradiation, the irradiator operator shall use a survey... irradiation, the irradiator operator shall: (1) Visually inspect the entire radiation room to verify that no...

10 CFR 36.67 - Entering and leaving the radiation room.

Code of Federal Regulations, 2012 CFR

2012-01-01

... radiation room of a panoramic irradiator after an irradiation, the irradiator operator shall use a survey... irradiation, the irradiator operator shall: (1) Visually inspect the entire radiation room to verify that no...

10 CFR 36.67 - Entering and leaving the radiation room.

Code of Federal Regulations, 2013 CFR

2013-01-01

... radiation room of a panoramic irradiator after an irradiation, the irradiator operator shall use a survey... irradiation, the irradiator operator shall: (1) Visually inspect the entire radiation room to verify that no...

Nuclear envelope: positioning nuclei and organizing synapses

PubMed Central

Razafsky, David; Hodzic, Didier

2015-01-01

The nuclear envelope plays an essential role in nuclear positioning within cells and tissues. This review highlights advances in understanding the mechanisms of nuclear positioning during skeletal muscle and central nervous system development. New findings, particularly about Atype lamins and Nesprin1, may link nuclear envelope integrity to synaptic integrity. Thus synaptic defects, rather than nuclear mispositioning, may underlie human pathologies associated with mutations of nuclear envelope proteins. PMID:26079712

Planetary nebula progenitors that swallow binary systems

NASA Astrophysics Data System (ADS)

Soker, Noam

2016-01-01

I propose that some irregular messy planetary nebulae (PNe) owe their morphologies to triple-stellar evolution where tight binary systems evolve inside and/or on the outskirts of the envelope of asymptotic giant branch (AGB) stars. In some cases, the tight binary system can survive, in others, it is destroyed. The tight binary system might break up with one star leaving the system. In an alternative evolution, one of the stars of the broken-up tight binary system falls towards the AGB envelope with low specific angular momentum, and drowns in the envelope. In a different type of destruction process, the drag inside the AGB envelope causes the tight binary system to merge. This releases gravitational energy within the AGB envelope, leading to a very asymmetrical envelope ejection, with an irregular and messy PN as a descendant. The evolution of the triple-stellar system can be in a full common envelope evolution or in a grazing envelope evolution. Both before and after destruction (if destruction takes place), the system might launch pairs of opposite jets. One pronounced signature of triple-stellar evolution might be a large departure from axisymmetrical morphology of the descendant PN. I estimate that about one in eight non-spherical PNe is shaped by one of these triple-stellar evolutionary routes.

A method to enhance the use of interaural time differences for cochlear implants in reverberant environments

PubMed Central

Monaghan, Jessica J. M.; Seeber, Bernhard U.

2017-01-01

The ability of normal-hearing (NH) listeners to exploit interaural time difference (ITD) cues conveyed in the modulated envelopes of high-frequency sounds is poor compared to ITD cues transmitted in the temporal fine structure at low frequencies. Sensitivity to envelope ITDs is further degraded when envelopes become less steep, when modulation depth is reduced, and when envelopes become less similar between the ears, common factors when listening in reverberant environments. The vulnerability of envelope ITDs is particularly problematic for cochlear implant (CI) users, as they rely on information conveyed by slowly varying amplitude envelopes. Here, an approach to improve access to envelope ITDs for CIs is described in which, rather than attempting to reduce reverberation, the perceptual saliency of cues relating to the source is increased by selectively sharpening peaks in the amplitude envelope judged to contain reliable ITDs. Performance of the algorithm with room reverberation was assessed through simulating listening with bilateral CIs in headphone experiments with NH listeners. Relative to simulated standard CI processing, stimuli processed with the algorithm generated lower ITD discrimination thresholds and increased extents of laterality. Depending on parameterization, intelligibility was unchanged or somewhat reduced. The algorithm has the potential to improve spatial listening with CIs. PMID:27586742

A novel intermediate in processing of murine leukemia virus envelope glycoproteins. Proteolytic cleavage in the late Golgi region.

PubMed

Bedgood, R M; Stallcup, M R

1992-04-05

The intracellular processing of the murine leukemia virus envelope glycoprotein precursor Pr85 to the mature products gp70 and p15e was analyzed in the mouse T-lymphoma cell line W7MG1. Kinetic (pulse-chase) analysis of synthesis and processing, coupled with endoglycosidase (endo H) and neuraminidase digestions revealed the existence of a novel high molecular weight processing intermediate, gp95, containing endo H-resistant terminally glycosylated oligosaccharide chains. In contrast to previously published conclusions, our data indicate that proteolytic cleavage of the envelope precursor occurs after the acquisition of endo H-resistant chains and terminal glycosylation and thus after the mannosidase II step. In the same W7MG1 cell line, the type and order of murine leukemia virus envelope protein processing events was identical to that for the mouse mammary tumor virus envelope protein. Interestingly, complete mouse mammary tumor virus envelope protein processing requires the addition of glucocorticoid hormone, whereas murine leukemia virus envelope protein processing occurs constitutively in these W7MG1 cells. We propose that all retroviral envelope proteins share a common processing pathway in which proteolytic processing is a late event that follows acquisition of endo H resistance and terminal glycosylation.

Mutations altering the gammaretrovirus endoproteolytic motif affect glycosylation of the envelope glycoprotein and early events of the virus life cycle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Argaw, Takele; Wilson, Carolyn A., E-mail: carolyn.wilson@fda.hhs.gov

Previously, we found that mutation of glutamine to proline in the endoproteolytic cleavage signal of the PERV-C envelope (RQKK to RPKK) resulted in non-infectious vectors. Here, we show that RPKK results in a non-infectious vector when placed in not only a PERV envelope, but also the envelope of a related gammaretrovirus, FeLV-B. The amino acid substitutions do not prevent envelope precursor cleavage, viral core and genome assembly, or receptor binding. Rather, the mutations result in the formation of hyperglycosylated glycoprotein and a reduction in the reverse transcribed minus strand synthesis and undetectable 2-LTR circular DNA in cells exposed to vectorsmore » with these mutated envelopes. Our findings suggest novel functions associated with the cleavage signal sequence that may affect trafficking through the glycosylation machinery of the cell. Further, the glycosylation status of the envelope appears to impact post-binding events of the viral life cycle, either membrane fusion, internalization, or reverse transcription. - Highlights: • Env cleavage signal impacts infectivity of gammaretroviruses. • Non-infectious mutants have hyper-glycosylated envelope that bind target cells. • Non-infectious mutants have defects in the formation of the double-stranded DNA. • Env cleavage motif has functions beyond cleavage of the env precursor.« less

Numerical simulation of dark envelope soliton in plasma

NASA Astrophysics Data System (ADS)

Wang, Fang-Ping; Han, Juan-fang; Zhang, Jie; Gao, Dong-Ning; Li, Zhong-Zheng; Duan, Wen-Shan; Zhang, Heng

2018-03-01

One-dimensional (1-D) particle-in-cell simulation is used to study the propagation of dark envelop solitons described by the nonlinear Schrödinger equation (NLSE) in electron-ion plasmas. The rational solution of the NLSE is presented, which is proposed as an effective tool for studying the dark envelope soliton in plasma. It is demonstrated by our numerical simulation that there is dark envelope soliton in electron-ion plasmas. The numerical results are in good agreements with the analytical ones from the NLSE which is obtained from the reductive perturbation method. The limitation of the amplitude of dark envelop solitons in plasma is noticed.

Envelope Protection for In-Flight Ice Contamination

NASA Technical Reports Server (NTRS)

Gingras, David R.; Barnhart, Billy P.; Ranaudo, Richard J.; Ratvasky, Thomas P.; Morelli, Eugene A.

2010-01-01

Fatal loss-of-control (LOC) accidents have been directly related to in-flight airframe icing. The prototype system presented in this paper directly addresses the need for real-time onboard envelope protection in icing conditions. The combinations of a-priori information and realtime aerodynamic estimations are shown to provide sufficient input for determining safe limits of the flight envelope during in-flight icing encounters. The Icing Contamination Envelope Protection (ICEPro) system has been designed and implemented to identify degradations in airplane performance and flying qualities resulting from ice contamination and provide safe flight-envelope cues to the pilot. Components of ICEPro are described and results from preliminary tests are presented.

Mechanism of protein import across the chloroplast envelope.

PubMed

Chen, K; Chen, X; Schnell, D J

2000-01-01

The development and maintenance of chloroplasts relies on the contribution of protein subunits from both plastid and nuclear genomes. Most chloroplast proteins are encoded by nuclear genes and are post-translationally imported into the organelle across the double membrane of the chloroplast envelope. Protein import into the chloroplast consists of two essential elements: the specific recognition of the targeting signals (transit sequences) of cytoplasmic preproteins by receptors at the outer envelope membrane and the subsequent translocation of preproteins simultaneously across the double membrane of the envelope. These processes are mediated via the co-ordinate action of protein translocon complexes in the outer (Toc apparatus) and inner (Tic apparatus) envelope membranes.

Further Validation of Simulated Dynamic Interface Testing Techniques as a Tool in the Forecasting of Air Vehicle Deck Limits

DTIC Science & Technology

2010-01-01

UAV Autonomy program which includes intelligent reasoning for autonomy, technologies to enhance see and avoid capabilities, object identification ...along the ship’s base recovery course (BRC). The pilot then flies toward the stern of the ship, aligning his approach path with the ship’s lineup line...quiescent point identification . CONCLUSIONS The primary goal for conducting dynamic interface analysis is to expand existing operating envelopes and

The design, development and qualification of a lightweight antenna pointing mechanism

NASA Technical Reports Server (NTRS)

Shmulevitz, M.; Halsband, A.

1996-01-01

This paper describes the design, development, and qualification of a new lightweight and compact Antenna Pointing Mechanism (APM). The APM was specially designed to meet the stringent mass, envelope, and environmental requirements of OFFEQ experimental satellite. During the development phase, some problems were encountered with the brushless DC motors, slip ring contact resistance, and bearing drag torque. All of these problems were resolved, and two APM units have been operating successfully in orbit since April, 1995.

Final analysis and design of a thermal protection system for 8-foot HTST combustor

NASA Technical Reports Server (NTRS)

Moskowitz, S.

1973-01-01

The cylindrical shell combustor with T-bar supports in the 8-foot HTST at the NASA-Langley Research Center encountered vibratory fatigue cracking over a period of 50-250 tunnel tests within a limited range of the required operating envelope. A preliminary design study provided several suitable thermal protection system designs for the combustor, one of which was a two-pass regenerative type air-cooled omega-shaped segment liner. A final design layout of the omega segment liner was prepared and analyzed for steady-state and transient conditions. The design of a support system for the fuel spray bar assembly was also included. Detail drawings suitable for fabrication purposes were also prepared. Liner design problems defined during the preliminary study included (1) the ingress of gas into the attachment bulb section of the omega segment, (2) the large thermal gradient along the leg of the omega bulb attachment section and, (3) the local peak metal temperature at the radius between the liner ID and the leg of the bulb attachment. These were resolved during the final design task. Analyses of the final design of the omega segment liner indicated that all design goals were met and the design provided the capability of operating over the required test envelope with a life expectancy substantially above the goal of 1500 cycles.

Robust Multivariable Optimization and Performance Simulation for ASIC Design

NASA Technical Reports Server (NTRS)

DuMonthier, Jeffrey; Suarez, George

2013-01-01

Application-specific-integrated-circuit (ASIC) design for space applications involves multiple challenges of maximizing performance, minimizing power, and ensuring reliable operation in extreme environments. This is a complex multidimensional optimization problem, which must be solved early in the development cycle of a system due to the time required for testing and qualification severely limiting opportunities to modify and iterate. Manual design techniques, which generally involve simulation at one or a small number of corners with a very limited set of simultaneously variable parameters in order to make the problem tractable, are inefficient and not guaranteed to achieve the best possible results within the performance envelope defined by the process and environmental requirements. What is required is a means to automate design parameter variation, allow the designer to specify operational constraints and performance goals, and to analyze the results in a way that facilitates identifying the tradeoffs defining the performance envelope over the full set of process and environmental corner cases. The system developed by the Mixed Signal ASIC Group (MSAG) at the Goddard Space Flight Center is implemented as a framework of software modules, templates, and function libraries. It integrates CAD tools and a mathematical computing environment, and can be customized for new circuit designs with only a modest amount of effort as most common tasks are already encapsulated. Customization is required for simulation test benches to determine performance metrics and for cost function computation.