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Sample records for aeronautical frequencies leakage

  1. Component external leakage and rupture frequency estimates

    SciTech Connect

    Eide, S.A.; Khericha, S.T.; Calley, M.B.; Johnson, D.A.; Marteeny, M.L.

    1991-11-01

    In order to perform detailed internal flooding risk analyses of nuclear power plants, external leakage and rupture frequencies are needed for various types of components - piping, valves, pumps, flanges, and others. However, there appears to be no up-to-date, comprehensive source for such frequency estimates. This report attempts to fill that void. Based on a comprehensive search of Licensee Event Reports (LERs) contained in Nuclear Power Experience (NPE), and estimates of component populations and exposure times, component external leakage and rupture frequencies were generated. The remainder of this report covers the specifies of the NPE search for external leakage and rupture events, analysis of the data, a comparison with frequency estimates from other sources, and a discussion of the results.

  2. 47 CFR 76.1804 - Aeronautical frequencies: leakage monitoring (CLI).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... carrier or other signal component with an average power level across a 25 kHz bandwidth in any 160... average powers measured over a 2.5 kHz bandwidth as described in the introductory paragraph to this rule..., shall be personally signed either electronically or manually by the operator; by one of the partners,...

  3. 47 CFR 76.1804 - Aeronautical frequencies: leakage monitoring (CLI).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... shall in that event separately set forth the reasons why the FCC Form 321 was not signed by the operator... attorney's knowledge), the attorney shall separately set forth the reasons for believing that...

  4. 47 CFR 76.1804 - Aeronautical frequencies: leakage monitoring (CLI).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... shall in that event separately set forth the reasons why the FCC Form 321 was not signed by the operator... attorney's knowledge), the attorney shall separately set forth the reasons for believing that...

  5. Radio frequency leakage current from unipolar laparoscopic electrocoagulators.

    PubMed

    DiNovo, J A

    1983-09-01

    Radio frequency (RF) leakage current has been suspected of causing accidental tissue burns associated with laparoscopic electrocoagulation used for tubal sterilization. A study was done to determine the levels of capacitively coupled RF leakage current from six unipolar laparoscopes manufactured by five companies. Leakage current values ranging from less than 100 mA to over 550 mA were measured at electrosurgical unit power settings of up to 150 w into 1,000 ohms. These levels represent 24-62% of the total electrosurgical current generated by the electrosurgical units. Using a criterion for tissue injury of 100 mA/sq cm applied for ten seconds, leakage current levels exceeding 400 mA are capable of producing burns either at the abdominal wall or to internal organs that accidentally come into contact with the body of the laparoscope. One of the six devices tested had leakage current levels higher than 400 mA at power settings lower than 100 w. Capacitance measurements between the unipolar laparoscope body and the forceps ranged from 53 to 140 picofarads. PMID:6226780

  6. 47 CFR 76.616 - Operation near certain aeronautical and marine emergency radio frequencies.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Operation near certain aeronautical and marine emergency radio frequencies. 76.616 Section 76.616 Telecommunication FEDERAL COMMUNICATIONS COMMISSION....616 Operation near certain aeronautical and marine emergency radio frequencies. (a) The...

  7. 47 CFR 76.616 - Operation near certain aeronautical and marine emergency radio frequencies.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... emergency radio frequencies. 76.616 Section 76.616 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical Standards § 76.616 Operation near certain aeronautical and marine emergency radio frequencies. (a) The...

  8. 47 CFR 76.616 - Operation near certain aeronautical and marine emergency radio frequencies.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... emergency radio frequencies. 76.616 Section 76.616 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical Standards § 76.616 Operation near certain aeronautical and marine emergency radio frequencies. (a) The...

  9. 47 CFR 76.616 - Operation near certain aeronautical and marine emergency radio frequencies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... emergency radio frequencies. 76.616 Section 76.616 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical Standards § 76.616 Operation near certain aeronautical and marine emergency radio frequencies. (a) The...

  10. 47 CFR 76.616 - Operation near certain aeronautical and marine emergency radio frequencies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... emergency radio frequencies. 76.616 Section 76.616 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical Standards § 76.616 Operation near certain aeronautical and marine emergency radio frequencies. (a) The...

  11. Monetizing Leakage Risk of Geologic CO2 Storage using Wellbore Permeability Frequency Distributions

    NASA Astrophysics Data System (ADS)

    Bielicki, Jeffrey; Fitts, Jeffrey; Peters, Catherine; Wilson, Elizabeth

    2013-04-01

    Carbon dioxide (CO2) may be captured from large point sources (e.g., coal-fired power plants, oil refineries, cement manufacturers) and injected into deep sedimentary basins for storage, or sequestration, from the atmosphere. This technology—CO2 Capture and Storage (CCS)—may be a significant component of the portfolio of technologies deployed to mitigate climate change. But injected CO2, or the brine it displaces, may leak from the storage reservoir through a variety of natural and manmade pathways, including existing wells and wellbores. Such leakage will incur costs to a variety of stakeholders, which may affect the desirability of potential CO2 injection locations as well as the feasibility of the CCS approach writ large. Consequently, analyzing and monetizing leakage risk is necessary to develop CCS as a viable technological option to mitigate climate change. Risk is the product of the probability of an outcome and the impact of that outcome. Assessment of leakage risk from geologic CO2 storage reservoirs requires an analysis of the probabilities and magnitudes of leakage, identification of the outcomes that may result from leakage, and an assessment of the expected economic costs of those outcomes. One critical uncertainty regarding the rate and magnitude of leakage is determined by the leakiness of the well leakage pathway. This leakiness is characterized by a leakage permeability for the pathway, and recent work has sought to determine frequency distributions for the leakage permeabilities of wells and wellbores. We conduct a probabilistic analysis of leakage and monetized leakage risk for CO2 injection locations in the Michigan Sedimentary Basin (USA) using empirically derived frequency distributions for wellbore leakage permeabilities. To conduct this probabilistic risk analysis, we apply the RISCS (Risk Interference of Subsurface CO2 Storage) model (Bielicki et al, 2013a, 2012b) to injection into the Mt. Simon Sandstone. RISCS monetizes leakage risk

  12. A frequency-domain channel model and emulator for aeronautical communications

    NASA Astrophysics Data System (ADS)

    Yang, Xiaopeng; Liang, Jun; Yao, Kun; Shi, Haoshan

    2005-11-01

    In this paper, we propose a frequency domain simulation structure for aeronautical wideband frequency-selective channel, which features ground-air and air-air wireless links. With appropriate channel parameters, the emulator can model the parking, taxi and en-route scenarios. The wideband frequency-selective channel consists of some parallel sub-channels in frequency domain, which are assumed to be independent to each other and have Rayleigh-distributed envelopes. The sub-channel models and emulators are based on a simple structure and characterized by flat fading. Through such decomposition approach, a frequency domain frequency-selective channel model can be achieved, which is suitable for an implementation of orthogonal frequency-division multiplexing (OFDM) or multi-carrier code-division multi-access (MC-CDMA) channel emulator on computer. Some appropriate emulator parameters have been proposed through channel sounding data collected for different scenarios. Particularly, in order to emulate the time-varying fading model well, the parameter sets are generated from time to time before the simulation with the same statistics.

  13. Modeling and damping of high-frequency leakage currents in PWM inverter-fed AC motor drive systems

    SciTech Connect

    Ogasawara, Satoshi; Akagi, Hirofumi

    1995-12-31

    This paper presents an equivalent circuit for high-frequency leakage currents in PWM inverter-fed ac motors, which forms a series resonant circuit. The analysis based on the equivalent circuit leads to such a conclusion that the connection of a conventional common-mode choke or reactor in series between the ac terminals of a PWM inverter and those of an ac motor is not effective to reduce the rms and average values of the leakage current, but effective to reduce the peak value. Furthermore, this paper proposes a common-mode transformer which is different in damping principle from the conventional common-mode choke. It is shown theoretically and experimentally that the common-mode transformer is able to reduce the rms value of the leakage current to 25%, where the core used in the common-mode transformer is smaller than that of the conventional common-mode choke.

  14. Reduced leakage in epitaxial BiFeO{sub 3} films following oxygen radio frequency plasma treatment

    SciTech Connect

    Kothari, Deepti; UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452 017 ; Upadhyay, Sanjay K.; Raghavendra Reddy, V.; Jariwala, C.; Raole, P. M.

    2013-06-07

    Epitaxial BiFeO{sub 3} (BFO) films were deposited using pulsed laser deposition method. The prepared films were characterized using x-ray diffraction, x-ray reflectivity, ferroelectric loop tracer, and leakage current measurements before and after oxygen plasma treatment. The leakage current of the films, a crucial parameter in device applications, is observed to be reduced by two orders of magnitude with oxygen plasma treatment at room temperature. P-E hysteresis loops were observed in oxygen plasma treated BFO films. The observed results indicate the usefulness of oxygen radio frequency plasma treatment (RF 13.56 MHz), which is an effective and low temperature processing technique, in such lossy ferroelectric thin films.

  15. Methods for rapid frequency-domain characterization of leakage currents in silicon nanowire-based field-effect transistors.

    PubMed

    Roinila, Tomi; Yu, Xiao; Verho, Jarmo; Li, Tie; Kallio, Pasi; Vilkko, Matti; Gao, Anran; Wang, Yuelin

    2014-01-01

    Silicon nanowire-based field-effect transistors (SiNW FETs) have demonstrated the ability of ultrasensitive detection of a wide range of biological and chemical targets. The detection is based on the variation of the conductance of a nanowire channel, which is caused by the target substance. This is seen in the voltage-current behavior between the drain and source. Some current, known as leakage current, flows between the gate and drain, and affects the current between the drain and source. Studies have shown that leakage current is frequency dependent. Measurements of such frequency characteristics can provide valuable tools in validating the functionality of the used transistor. The measurements can also be an advantage in developing new detection technologies utilizing SiNW FETs. The frequency-domain responses can be measured by using a commercial sine-sweep-based network analyzer. However, because the analyzer takes a long time, it effectively prevents the development of most practical applications. Another problem with the method is that in order to produce sinusoids the signal generator has to cope with a large number of signal levels. This may become challenging in developing low-cost applications. This paper presents fast, cost-effective frequency-domain methods with which to obtain the responses within seconds. The inverse-repeat binary sequence (IRS) is applied and the admittance spectroscopy between the drain and source is computed through Fourier methods. The methods is verified by experimental measurements from an n-type SiNW FET. PMID:25161832

  16. Leakage tests reduce the frequency of biliary fistulas following hydatid liver cyst surgery

    PubMed Central

    Kayaalp, Cuneyt; Aydin, Cemalettin; Olmez, Aydemir; Isik, Sevil; Yilmaz, Sezai

    2011-01-01

    BACKGROUND AND AIM: Biliary fistulas are the most common morbidity (8.2-26%) following hydatid liver surgery. The aim of our study was to reduce the incidence of postoperative biliary fistulas after the suturing of cystobiliary communications by applying a bile leakage test. PATIENTS AND METHODS: A total of 133 hydatid liver cysts from 93 patients were divided into two groups, according to whether the test was performed. Tests were performed on 56 cysts from 34 patients, and the remaining 77 cysts from 59 patients were treated without the test. In both groups, all visible biliary orifices in the cysts were suture ligated, and drains were placed in all cysts. The visibility of the biliary orifices and postoperative biliary drainage through the drains were recorded. Patients in both groups were also compared with respect to the number of days living with the drains, the length of the hospital stay, and secondary interventions related to biliary complications. RESULTS: Biliary orifices were more visible in the tested cysts (13% vs. 48%; P <0.001). Fewer biliary complications occurred in the tested patients (8.8% vs. 27.7%, P = 0.033). The mean drain removal time (4.1±3.3 days vs. 6.8±8.9 days, P<0.05) and the length of the hospital stay (6.7±2.7 days vs. 9.7±6.3 days, P<0.01) were shorter for the tested patients. None of the patients in the test group required postoperative Endoscopic retrograde cholangiopancreaticography (ERCP) or nasobiliary drainage (0.0% vs. 8.4%, P  =  0.09). There were no long-term biliary complications for either group after three years of follow-up. CONCLUSIONS: Identification of biliary orifices with a bile leakage test and the suturing of cystobiliary communications significantly reduced postoperative biliary complications following hydatid liver surgery. PMID:21552666

  17. NASA aeronautics

    NASA Technical Reports Server (NTRS)

    Anderton, D. A.

    1982-01-01

    Aeronautical research programs are discussed in relation to research methods and the status of the programs. The energy efficient aircraft, STOL aircraft and general aviation aircraft are considered. Aerodynamic concepts, rotary wing aircraft, aircraft safety, noise reduction, and aircraft configurations are among the topics included.

  18. [Exploring Aeronautics

    NASA Technical Reports Server (NTRS)

    Robinson, Brandi

    2004-01-01

    This summer I have been working with the N.A.S.A. Project at Cuyahoga Community College (Tri-C) under the title of Exploring Aeronautics Project Leader. The class that I have worked with is comprised of students that will enter the eighth grade in the fall of 2004. The program primarily focuses upon math proficiency and individualized class projects. My duties have encompassed both realms. During the first 2-3 weeks of my internship, I worked at NASA Glenn Research Center (GRC) researching, organizing, and compiling information for weekly Scholastic Challenges and the Super Scholastic Challenge. I was able to complete an overview of Scholastic Challenge and staff responsibilities regarding the competition; a proposal for an interactive learning system, Quizdom; a schedule for challenge equipment, as well as a schedule listing submission deadlines for the staff. Also included in my tasks, during these first 2-3 weeks, were assisting Tammy Allen and Candice Thomas with the student application review and interview processes for student applicants. For the student and parent orientation, I was assigned publications and other varying tasks to complete before the start of the program. Upon the commencement of the program, I changed location from NASA GRC to Tri-C Metro Campus, where student classes for the Cleveland site are held. During the duration of the program, I work with the instructor for the Exploring Aeronautics class, kkkk, assisting in classroom management, daily attendance, curriculum, project building, and other tasks as needed. These tasks include the conducting of the weekly competition, known as Scholastic Challenge. As a Project Leader, I am also responsible for one subject area of the Scholastic Challenge aspect of the N.A.S.A. Project curriculum. Each week I have to prepare a mission that the participants will take home the following Monday and at least 10 questions that will be included in the pool of questions used for the Scholastic Challenge

  19. Proposal of Detection Method of Leakage Current between Electrodes of a Contaminated and Wetted Cord Plug by Superimposed High Frequency Signal

    NASA Astrophysics Data System (ADS)

    Yagi, Masahiro; Mizuno, Yukio; Nakagawa, Toshiyuki

    Tracking of a cord plug caused by leakage current flowing between its electrodes, which is observed under contaminated and wetted conditions, is attributed to one of the causes of fire accidents. Demands of society for establishment of countermeasures against this type of tracking have become stronger since the number of fire accidents by the tracking has been increased in the recent ten years. However, it seems rather difficult to detect the leakage current because its magnitude is much smaller than that of a typical load current of a household appliance. In this paper, a novel method to detect the existence of the leakage current is proposed, where a high frequency signal superimposed on a load current is detected instead of detecting the leakage current itself. It was confirmed by laboratory experiments that the signal could be detected only when wetted dust was in the space between a cord plug and an outlet. The proposed method seems promising to detect of tracking of a cord plug with high frequency signal.

  20. ACTS broadband aeronautical experiment

    NASA Technical Reports Server (NTRS)

    Abbe, Brian S.; Jedrey, Thomas C.; Estabrook, Polly; Agan, Martin J.

    1993-01-01

    In the last decade, the demand for reliable data, voice, and video satellite communication links between aircraft and ground to improve air traffic control, airline management, and to meet the growing demand for passenger communications has increased significantly. It is expected that in the near future, the spectrum required for aeronautical communication services will grow significantly beyond that currently available at L-band. In anticipation of this, JPL is developing an experimental broadband aeronautical satellite communications system that will utilize NASA's Advanced Communications Technology Satellite (ACTS) as a satellite of opportunity and the technology developed under JPL's ACTS Mobile Terminal (AMT) Task to evaluate the feasibility of using K/Ka-band for these applications. The application of K/Ka-band for aeronautical satellite communications at cruise altitudes is particularly promising for several reasons: (1) the minimal amount of signal attenuation due to rain; (2) the reduced drag due to the smaller K/Ka-band antennas (as compared to the current L-band systems); and (3) the large amount of available bandwidth. The increased bandwidth available at these frequencies is expected to lead to significantly improved passenger communications - including full-duplex compressed video and multiple channel voice. A description of the proposed broadband experimental system will be presented including: (1) applications of K/Ka-band aeronautical satellite technology to U.S. industry; (2) the experiment objectives; (3) the experiment set-up; (4) experimental equipment description; and (5) industrial participation in the experiment and the benefits.

  1. Fundamental Aeronautics Program

    NASA Technical Reports Server (NTRS)

    Misra, Ajay

    2009-01-01

    The Overarching Mission of NASA's Aeronautics Research Mission Directorate (ARMD) is: To advance U.S. technological leadership in aeronautics in partnership with industry, academia, and other government agencies that conduct aeronautics-related research. ARMD supports the Agency's goal of developing a balanced overall program of science, exploration, and aeronautics, and ARMD's research plans also directly support the National Aeronautics R&D Policy and accompanying Executive Order 131419.

  2. Achieving Aeronautics Leadership: Aeronautics Strategic Enterprise Plan

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Today, more than ever, aggressive leadership is required to ensure that our national investments in aeronautical research, technology, and facilities are shaped into a coordinated, and high-impact, strategy. Under the auspices of the National Science and Technology Council, and in conjunction with the domestic industry, universities, the Department of Defense, and the Federal Aviation Administration - our partners in aeronautics - we propose to provide that leadership, and this document is our plan.

  3. Western Aeronautical Test Range

    NASA Technical Reports Server (NTRS)

    Sakahara, Robert D.

    2008-01-01

    This viewgraph presentation reviews the work of the Western Aeronautical Test Range (WATR). NASA's Western Aeronautical Test Range is a network of facilities used to support aeronautical research, science missions, exploration system concepts, and space operations. The WATR resides at NASA's Dryden Flight Research Center located at Edwards Air Force Base, California. The WATR is a part of NASA's Corporate Management of Aeronautical Facilities and funded by the Strategic Capability Asset Program (SCAP). Maps show the general location of the WATR area that is used for aeronautical testing and evaluation. The products, services and facilities of WATR are discussed,

  4. Mathematical analysis of marine pipeline leakage monitoring system based on coherent OTDR with improved sensor length and sampling frequency

    NASA Astrophysics Data System (ADS)

    Pnev, A. B.; Zhirnov, A. A.; Stepanov, K. V.; Nesterov, E. T.; Shelestov, D. A.; Karasik, V. E.

    2015-01-01

    A system based on coherent optical time domain reflectometry (OTDR) for subsea pipeline monitoring is described. The fiber sensor length is increased using erbium-doped fiber amplifier (EDFA) cascades. The sampling frequency is increased by dividing the fiber sensor into separate sensitive areas, with parallel scanning. The calculation of the erbium amplifier cascade spontaneous noise influence on the signal-to-noise ratio (SNR) is carried out.

  5. Nomenclature for Aeronautics

    NASA Technical Reports Server (NTRS)

    1927-01-01

    This nomenclature for aeronautics was prepared by a Special Conference on Aeronautical Nomenclature by the executive committee of the National Advisory Committee for Aeronautics at a meeting held on August 19, 1924, at which meeting Dr. Joseph S. Ames was appointed chairman of the conference. The conference was composed of representatives of the National Advisory Committee for Aeronautics and specially appointed representatives officially designated by the Army Air Service, the Bureau of Aeronautics of the Navy Department, the Bureau of Standards, the American Society of Mechanical Engineers, the Society of Automotive Engineers, and the Aeronautical Chamber of Commerce. The purpose of the committee in the preparation and publication of this report is to secure uniformity in the official documents of the government and, as far as possible, in technical and other commercial publications

  6. Nomenclature for Aeronautics

    NASA Technical Reports Server (NTRS)

    1924-01-01

    This nomenclature for aeronautics was prepared by a special conference on aeronautical nomenclature by the Executive Committee of the National Advisory Committee for Aeronautics at a meeting held August 11, 1933. This publication supersedes all previous publications of the committee on this subject. The purpose of the committee in the preparation and publication of this report is to secure uniformity in the official documents of the government and, as far as possible, in technical and other commercial publications.

  7. Nomenclature for Aeronautics

    NASA Technical Reports Server (NTRS)

    1923-01-01

    This nomenclature for aeronautics was prepared by a special conference on aeronautical nomenclature, composed of representatives of the Army and Navy Air Services, the Air Mail Service, the Bureau of Standards, the National Advisory Committee for Aeronautics, and private life. This report supersedes all previous publications of the committee on this subject. It is published with the intention of securing greater uniformity and accuracy in official documents of the government, and, as far as possible, in technical and other commercial publications. (author)

  8. NASA thesaurus aeronautics vocabulary

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The controlled vocabulary used by the NASA Scientific and Technical Information effort to index documents in the area of aeronautics is presented. The terms comprise a subset of the 1988 edition of the NASA Thesaurus and its supplements issued through the end of 1990. The Aeronautics Vocabulary contains over 4700 terms presented in a hierarchical display format. In addition to aeronautics per se, the vocabulary covers supporting terminology from areas such as fluid dynamics, propulsion engineering, and test facilities and instrumentation.

  9. Exceptional paternal inheritance of plastids in Arabidopsis suggests that low-frequency leakage of plastids via pollen may be universal in plants.

    PubMed

    Azhagiri, Arun K; Maliga, Pal

    2007-12-01

    Plastid DNA is absent in pollen or sperm cells of Arabidopsis thaliana. Accordingly, plastids and mitochondria, in a standard genetic cross, are transmitted to the seed progeny by the maternal parent only. Our objective was to test whether paternal plastids are transmitted by pollen as an exception. The maternal parent in our cross was a nuclear male sterile (ms1-1/ms1-1), spectinomycin-sensitive Ler plant. It was fertilized with pollen of a male fertile RLD-Spc1 plant carrying a plastid-encoded spectinomycin resistance mutation. Seedlings with paternal plastids were selected by spectinomycin resistance encoded in the paternal plastid DNA. Our data, in general, support maternal inheritance of plastids in A. thaliana. However, we report that paternal plastids are transmitted to the seed progeny in Arabidopsis at a low (3.9 x 10(-5)) frequency. This observation extends previous reports in Antirrhinum majus, Epilobium hirsutum, Nicotiana tabacum, Petunia hybrida, and the cereal crop Setaria italica to a cruciferous species suggesting that low-frequency paternal leakage of plastids via pollen may be universal in plants previously thought to exhibit strict maternal plastid inheritance. The genetic tools employed here will facilitate testing the effect of Arabidopsis nuclear mutations on plastid inheritance and allow for the design of mutant screens to identify nuclear genes controlling plastid inheritance. PMID:17931353

  10. Nomenclature for aeronautics

    NASA Technical Reports Server (NTRS)

    1920-01-01

    Report defines the principal terms which have come into use in the development of aeronautics. It was prepared in cooperation with a committee engaged upon a similar undertaking in Great Britain. As a result this nomenclature is in substantial agreement with the one which has been adopted by the aeronautical authorities of Great Britain.

  11. Bibliography of Aeronautics: 1926

    NASA Technical Reports Server (NTRS)

    Brockett, Paul

    1928-01-01

    This Bibliography of Aeronautics for 1926 covers the aeronautical literature published from January 1 to December 31, 1926. The first Bibliography of Aeronautics was published by the Smithsonian Institution as volume 55 of the Smithsonian Miscellaneous Collections and covered the material published prior to June 30, 1909. Supplementary volumes of the Bibliography of Aeronautics for the subsequent years have been published by the National Advisory Committee for Aeronautics. The last preceding volume was for the calendar year 1925. As in the previous volumes, citations of the publications of all nations are included in the languages in which these publications originally appeared. The arrangement is dictionary form with author find subject entry, and one alphabetical arrangement. Detail in the matter of subject reference has been omitted on aCC01.mt of the cost of presentation, but an attempt has been made to give sufficient cross reference for research in special lines.

  12. Bibliography of Aeronautics: 1928

    NASA Technical Reports Server (NTRS)

    Brockett, Paul

    1928-01-01

    This Bibliography of Aeronautics for 1928 covers the aeronautical literature published from January 1 to December 31, 1928. The first Bibliography of Aeronautics was published by the Smithsonian Institution as volume 55 of the Smithsonian Miscellaneous Collections and covered the material published prior to June 30, 1909. Supplementary volumes of the Bibliography of Aeronautics for the subsequent years have been published by the National Advisory Committee for Aeronautics. The last preceding volume was for the calendar year 1927. As in the previous volumes, citations of the publications of all nations are included in the languages in which these publications originally appeared. The arrangement is in dictionary form with author and subject entry, and one alphabetical arrangement. Detail in the matter of subject reference has been omitted on account of the cost of presentation, but an attempt has been made to give sufficient cross reference for research in special lines.

  13. Bibliography of Aeronautics: 1932

    NASA Technical Reports Server (NTRS)

    1935-01-01

    This Bibliography of Aeronautics for 1932 covers the aeronautical literature published from January 1 to December 31, 1932. The first Bibliography of Aeronautics was published by the Smithsonian Institution as volume 55 of the Smithsonian Miscellaneous Collections and covered the material published prior to June 30, 1909. Supplementary volumes of the Bibliography of Aeronautics for the subsequent years have been published by the National Advisory Committee for Aeronautics. The last preceding volume was for the calendar year 1931. As in the previous volumes, citations of the publications of all nations are included in the languages in which these publications originally appeared. The arrangement is in dictionary form with author and subject entry and one alphabetical arrangement. Detail in the matter of subject reference has been omitted on account of the cost of presentation, but an attempt has been made to give sufficient cross-reference for research in special lines.

  14. Bibliography of Aeronautics, 1929

    NASA Technical Reports Server (NTRS)

    Brockett, Paul

    1930-01-01

    This Bibliography of Aeronautics for 1929 covers the aeronautical literature published from January 1 to December 31, 1929. The first Bibliography of Aeronautics was published by the Smithsonian Institution as Volume 55 of the Smithsonian Miscellaneous Collections and covered the material published prior to June 30, 1909. Supplementary volumes of the Bibliography of Aeronautics for the subsequent years have been published by the National Advisory Committee for Aeronautics. The last preceding volume was for the calendar year 1928. As in the previous volumes, citations of the pUblications of all nations are included in th.e languages in which. these publications originally appeared. The arrangement is in dictionary form with author and subject entry, and one alphabetical arrangement. Detail in the matter of subject reference has been omitted on account of the cost of presentation, but an attempt has been made to give sufficient cross reference for research in special lines.

  15. Nomenclature for Aeronautics

    NASA Technical Reports Server (NTRS)

    1939-01-01

    The nomenclature for aeronautics presented in this Report No. 474 is a revision of the last previous report on this subject (i.e., Report no. 240.) This report is published for the purpose of encouraging greater uniformity and precision in the use of terms relating to aeronautics, both in official documents of the Government and in commercial publications. Terms in general use in other branches of engineering have been included only where they have some special significance in aeronautics, or form an integral part of its terminology.

  16. Curriculum for modern aeronautics

    NASA Technical Reports Server (NTRS)

    Roberts, L.

    1975-01-01

    Methods for improving the university training of aeronautical engineering students are discussed. Specific topics considered are: (1) the kind of students which should be developed through aeronautical engineering education, (2) to what extent should aerospace engineering be prepared for diversity and change, (3) to what extent should theory be emphasized as compared with practical engineering and design, and (4) a suggestion for NASA/Industry/University collaboration.

  17. Western Aeronautical Test Range

    NASA Technical Reports Server (NTRS)

    Sakahara, Robert D.

    2008-01-01

    NASA's Western Aeronautical Test Range (WATR) is a network of facilities used to support aeronautical research, science missions, exploration system concepts, and space operations. The WATR resides at NASA's Dryden Flight Research Center located at Edwards Air Force Base, California. The WATR is a part of NASA's Corporate Management of Aeronautical Facilities and funded by the Strategic Capability Asset Program (SCAP). It is managed by the Aeronautics Test Program (ATP) of the Aeronautics Research Mission Directorate (ARMD) to provide the right facility at the right time. NASA is a tenant on Edwards Air Force Base and has an agreement with the Air Force Flight Test Center to use the land and airspace controlled by the Department of Defense (DoD). The topics include: 1) The WATR supports a variety of vehicles; 2) Dryden shares airspace with the AFFTC; 3) Restricted airspace, corridors, and special use areas are available for experimental aircraft; 4) WATR Products and Services; 5) WATR Support Configuration; 6) Telemetry Tracking; 7) Time Space Positioning; 8) Video; 9) Voice Communication; 10) Mobile Operations Facilities; 11) Data Processing; 12) Mission Control Center; 13) Real-Time Data Analysis; and 14) Range Safety.

  18. Diaphragms for Aeronautic Instruments

    NASA Technical Reports Server (NTRS)

    Hersey, M D

    1924-01-01

    This investigation was carried out at the request of the National Advisory Committee for Aeronautics and comprises an outline of historical developments and theoretical principles, together with a discussion of expedients for making the most effective use of existing diaphragms actuated by the hydrostatic pressure form an essential element of a great variety instruments for aeronautic and other technical purposes. The various physical data needed as a foundation for rational methods of diaphragm design have not, however, been available hitherto except in the most fragmentary form.

  19. Advanced Civilian Aeronautical Concepts

    NASA Technical Reports Server (NTRS)

    Bushnell, Dennis M.

    1996-01-01

    Paper discusses alternatives to currently deployed systems which could provide revolutionary improvements in metrics applicable to civilian aeronautics. Specific missions addressed include subsonic transports, supersonic transports and personal aircraft. These alternative systems and concepts are enabled by recent and envisaged advancements in electronics, communications, computing and Designer Fluid Mechanics in conjunction with a design approach employing extensive synergistic interactions between propulsion, aerodynamics and structures.

  20. Aeronautical facilities assessment

    NASA Technical Reports Server (NTRS)

    Penaranda, F. E. (Compiler)

    1985-01-01

    A survey of the free world's aeronautical facilities was undertaken and an evaluation made on where the relative strengths and weaknesses exist. Special emphasis is given to NASA's own capabilities and needs. The types of facilities surveyed are: Wind Tunnels; Airbreathing Propulsion Facilities; and Flight Simulators

  1. ARMD Fundamental Aeronautics Program

    NASA Technical Reports Server (NTRS)

    Dryer, Jay; DelRosario, Ruben

    2010-01-01

    This slide presentation focuses work of the Aeronautics Research Mission Directorate (ARMD) with particular interest on the work being done to address the environmental and energy efficiency challenges. Particular interest is on the Subsonic Fixed Wing (SFW) project, though there is discussion of the rotorcraft and the supersonics environmental challenges.

  2. Reduction of Transverse Surface Acoustic Wave Leakage in Resonator on Al/42° YX-LiTaO3 Substrate for High-Frequency Applications

    NASA Astrophysics Data System (ADS)

    Komatsu, Tomoya; Nakamura, Hiroyuki; Nakanishi, Hidekazu; Turunari, Tetsuya; Fujiwara, Joji

    2013-07-01

    In this paper, we propose a new structure for reducing the extent of transverse surface acoustic wave (SAW) leakage for the SAW resonator on a 42° YX-LiTaO3 substrate. Such leakage occurs from the interdigital region toward the busbar region in the SAW resonators. The new structure has a Ta2O5 film outside the interdigital region. This structure can make the SAW velocity in the busbar region lower than the velocity in the interdigital region. Therefore, the new structure could reduce the extent of leakage, and contribute to confine the SAW energy in the interdigital region. This structure was applied in SAW resonators and ladder-type SAW filters fabricated on a 42° YX-LiTaO3 substrate. The insertion loss could be improved by suppressing transverse SAW leakage. This technique could be applied to the fabrication of the filters and duplexers using leaky SAW on a 42° YX-LiTaO3 substrate, and the SAW devices could exhibit excellent performance.

  3. Reshaping NASA's Aeronautics Program

    NASA Technical Reports Server (NTRS)

    Liang, Anita D.

    2007-01-01

    We will dedicate ourselves to the mastery and intellectual stewardship of the core competencies of Aeronautics for the Nation in all flight regimes. We will focus our research in areas that are appropriate to NASA's unique capabilities. we will directly address the R&D needs of the Next Generation Air Transportation System (NGATS) in partnership with the member agencies of the Joint Planning and development Office (JPDO).

  4. Aeronautical audio broadcasting via satellite

    NASA Astrophysics Data System (ADS)

    Tzeng, Forrest F.

    A system design for aeronautical audio broadcasting, with C-band uplink and L-band downlink, via Inmarsat space segments is presented. Near-transparent-quality compression of 5-kHz bandwidth audio at 20.5 kbit/s is achieved based on a hybrid technique employing linear predictive modeling and transform-domain residual quantization. Concatenated Reed-Solomon/convolutional codes with quadrature phase shift keying are selected for bandwidth and power efficiency. RF bandwidth at 25 kHz per channel, and a decoded bit error rate at 10(exp -6) with E(sub b)/N(sub o) at 3.75 dB are obtained. An interleaver, scrambler, modem synchronization, and frame format were designed, and frequency-division multiple access was selected over code-division multiple access. A link budget computation based on a worst-case scenario indicates sufficient system power margins. Transponder occupancy analysis for 72 audio channels demonstrates ample remaining capacity to accommodate emerging aeronautical services.

  5. Aeronautical audio broadcasting via satellite

    NASA Technical Reports Server (NTRS)

    Tzeng, Forrest F.

    1993-01-01

    A system design for aeronautical audio broadcasting, with C-band uplink and L-band downlink, via Inmarsat space segments is presented. Near-transparent-quality compression of 5-kHz bandwidth audio at 20.5 kbit/s is achieved based on a hybrid technique employing linear predictive modeling and transform-domain residual quantization. Concatenated Reed-Solomon/convolutional codes with quadrature phase shift keying are selected for bandwidth and power efficiency. RF bandwidth at 25 kHz per channel, and a decoded bit error rate at 10(exp -6) with E(sub b)/N(sub o) at 3.75 dB are obtained. An interleaver, scrambler, modem synchronization, and frame format were designed, and frequency-division multiple access was selected over code-division multiple access. A link budget computation based on a worst-case scenario indicates sufficient system power margins. Transponder occupancy analysis for 72 audio channels demonstrates ample remaining capacity to accommodate emerging aeronautical services.

  6. NASA's Role in Aeronautics: A Workshop. Volume VI - Aeronautical Research.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Assembly of Engineering.

    The central task of a 1980 workshop on the role of the National Aeronautics and Space Administration (NASA) in aeronautics was to examine the relationship of NASA's research capabilities to the state of U.S. aviation and to make recommendations about NASA's future role in aeronautics. Following a brief introduction, the Overview Panel on…

  7. Dimensioning of Aeronautical Satellite Services

    NASA Astrophysics Data System (ADS)

    Holzbock, M.; Jahn, A.; Werner, M.

    2002-01-01

    This paper will provide a generalised baseline for a systematic AirCom design process and address in particular the dimensioning of satellite systems for aeronautical services. These services will roll out soon in medium- and long-haul aircraft. The offered services will range from low rate telephony, internet access, and streaming applications for video and audio. The aggregate bit rates on up- and downlink will certainly be statistically time-dependent and asymmetric in forward and backward direction. A tool will be described that is able to model this traffic. Furthermore the dimensioning of satellite constellations can be done. Due to the stochastic nature of the traffic, multi-service models for the traffic generation of different services will be described. Furthermore, the traffic will be affected by the available bit rate and shaping or blocking will equalize the peak loads. If fleets with many aircraft are considered, aeronautical traffic models must be based on actual aircraft routes, flight schedules, location and time of day, as well as seats per aircraft and type of aircraft (charter, business etc.). The regionally distributed traffic has to be served by several satellites and appropriate sharing of the serving satellites may spread the traffic in hot zones and yield a better load distribution. When aeronautical services will spread out, the capacity demand will grow quickly and the capacity of existing Ku-band GEO satellites will soon be exceeded. Changing to higher frequency bands will provide large spectrum portions and smaller spotbeams will allow better frequency reuse. Even constellations with non-geostationary satellites could be re-advent to serve better the higher latitude regions. Then, another mobility component for the fast changing satellite topology need to be addressed, and routing issues of the traffic must be considered. The paper will describe solutions for the mapping of satellites and traffic demand as well as routing algorithms

  8. Aeronautical Science Course of Study.

    ERIC Educational Resources Information Center

    Southbay Union High School District, Redondo Beach, CA.

    This revision of "Aeronautical Science Course of Study for California High Schools," first issued in 1967, is designed by and for the use of teachers of high school aeronautical courses. It differs from other aeronautical instructional materials in its emphasis on inquiry, exploration, and open-ended experimentation. The eleven units may be used…

  9. Aeronautics in the American Society

    NASA Technical Reports Server (NTRS)

    Fletcher, J. C.

    1975-01-01

    The trends in aeronautics and aeronautical education are discussed with respect to the roles of industry, government, and the universities. The importance of the aviation industry to the economy of the country is examined. The impact of reduced enrollment of aeronautical engineering students in the universities on the future of the aeronautical industry is stressed. It is stated that the role of the government should be to sponsor and conduct basic research and advanced technology programs for civil and military aviation, and the specification, development, procurement, and operation of military aircraft. Recommendations are made for approaches which may be taken to influence more qualified students to enter the field of aeronautics.

  10. Aeronautical tubes and pipes

    NASA Astrophysics Data System (ADS)

    Beauclair, N.

    1984-12-01

    The main and subcomponent French suppliers of aircraft tubes and pipes are discussed, and the state of the industry is analyzed. Quality control is essential for tubes with regard to their i.d. and metallurgical compositions. French regulations do not allow welded seam tubes in hydraulic circuits unless no other form is available, and then rustproofed steel must be installed. The actual low level of orders for any run of tubes dictates that the product is only one of several among the manufacturers' line. Automation, both in NDT and quality control, assures that the tubes meet specifications. A total of 10 French companies participate in the industry, serving both civil and military needs, with some companies specializing only in titanium, steel, or aluminum materials. Concerns wishing to enter the market must upgrade their equipment to meet the higher aeronautical specifications and be prepared to furnish tubes and pipes that serve both functional and structural purposes simultaneously. Additionally, pipe-bending machines must also perform to tight specifications. Pipes can range from 0.2 mm exterior diameter to 40 mm, with wall thicknesses from 0.02 mm to 3 mm. A chart containing a list of manufacturers and their respective specifications and characteristics is presented, and a downtrend in production with reduction of personnel is noted.

  11. Aeronautical Engineering: 1983 cumulative index

    NASA Technical Reports Server (NTRS)

    1984-01-01

    This bibliography is a cumulative index to the abstracts contained in NASA SP-7037 (158) through NASA SP-7037 (169) of Aeronautical Engineering: A Continuing Bibliography. NASA SP-7037 and its supplements have been compiled through the cooperative efforts of the American Institute of Aeronautics and Astronautics (AIAA) and the National Aeronautics and Space Administration (NASA). This cumulative index includes subject, personal author, corporate source, contract, report number, and accession number indexes.

  12. Aeronautics in NACA and NASA

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Initiated in 1915, the National Advisory Committee for Aeronautics/National Aeronautics and Space Administration (NACA/NASA) aeronautical programs have been the keystone of a sustained U.S. Government, industry, and university research effort which has been a primary factor in the development of our remarkable air transportation systems, the country's largest positive trade balance component, and the world's finest military Air Force. This overview summarizes the flow of events, and the major trends, that have led from the NACA origins to the present NASA Aeronautics program, and indicates some important directions for the years ahead.

  13. Aeronautical concerns and National Aeronautics and Space Administration atmospheric electricity projects

    NASA Technical Reports Server (NTRS)

    Vaughan, W. W.

    1980-01-01

    The phenomenology of lightning and lightning measurement techniques are briefly examined with a particular reference to aeronautics. Developments made in airborne and satellite detection methods are reported. NASA research efforts are outlined which cover topics including in-situ measurements, design factors and protection, remote optical and radio frequency measurements, and space vehicle design.

  14. Aeronautical Engineering: A continuing bibliography

    NASA Technical Reports Server (NTRS)

    1982-01-01

    This bibliography lists 347 reports, articles and other documents introduced into the scientific and technical information system. Documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated compounds, equipment, and systems are included. Research and development in aerodynamics, aeronautics and ground support equipment for aeronautical vehicles are also included.

  15. Fifty Years of Aeronautical Research.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    This booklet contains a detailed review of the aeronautical research conducted at Langley Research Center during the 50 years after its construction in 1917 as the first research laboratory for the National Advisory Committee for Aeronautics. The research is discussed in five parts, by decades: 1917-27, 1928-37, 1938-47, 1948-57, 1958-67.…

  16. Land-use Leakage

    SciTech Connect

    Calvin, Katherine V.; Edmonds, James A.; Clarke, Leon E.; Bond-Lamberty, Benjamin; Kim, Son H.; Wise, Marshall A.; Thomson, Allison M.; Kyle, G. Page

    2009-12-01

    Leakage occurs whenever actions to mitigate greenhouse gas emissions in one part of the world unleash countervailing forces elsewhere in the world so that reductions in global emissions are less than emissions mitigation in the mitigating region. While many researchers have examined the concept of industrial leakage, land-use policies can also result in leakage. We show that land-use leakage is potentially as large as or larger than industrial leakage. We identify two potential land-use leakage drivers, land-use policies and bioenergy. We distinguish between these two pathways and run numerical experiments for each. We also show that the land-use policy environment exerts a powerful influence on leakage and that under some policy designs leakage can be negative. International “offsets” are a potential mechanism to communicate emissions mitigation beyond the borders of emissions mitigating regions, but in a stabilization regime designed to limit radiative forcing to 3.7 2/m2, this also implies greater emissions mitigation commitments on the part of mitigating regions.

  17. Predicting Leakage in Labyrinth Seals

    NASA Technical Reports Server (NTRS)

    Morrison, G. L.; Rhode, D. L.; Cogan, K. C.; Chi, D.; Demko, J.

    1985-01-01

    Analytical and empirical methods evaluated. 264-page report presents comprehensive information on leakage in labyrinth seals. Summarizes previous analyses of leakage, reviews leakage tests conducted by authors and evaluates various analytical and experimental methods of determining leakage and discusses leakage prediction techniques.

  18. NASA Aeronautics Research: An Assessment

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The U.S. air transportation system is vital to the economic well-being and security of the United States. To support continued U.S. leadership in aviation, Congress and NASA requested that the National Research Council undertake a decadal survey of civil aeronautics research and technology (R&T) priorities that would help NASA fulfill its responsibility to preserve U.S. leadership in aeronautics technology. In 2006, the National Research Council published the Decadal Survey of Civil Aeronautics. That report presented a set of six strategic objectives for the next decade of aeronautics R&T, and it described 51 high-priority R&T challenges--characterized by five common themes--for both NASA and non-NASA researchers. The National Research Council produced the present report, which assesses NASA's Aeronautics Research Program, in response to the National Aeronautics and Space Administration Authorization Act of 2005 (Public Law 109-155). This report focuses on three sets of questions: 1. How well does NASA's research portfolio implement appropriate recommendations and address relevant high-priority research and technology challenges identified in the Decadal Survey of Civil Aeronautics? If gaps are found, what steps should be taken by the federal government to eliminate them? 2. How well does NASA's aeronautics research portfolio address the aeronautics research requirements of NASA, particularly for robotic and human space exploration? How well does NASA's aeronautics research portfolio address other federal government department/agency non-civil aeronautics research needs? If gaps are found, what steps should be taken by NASA and/or other parts of the federal government to eliminate them? 3. Will the nation have a skilled research workforce and research facilities commensurate with the requirements in (1) and (2) above? What critical improvements in workforce expertise and research facilities, if any, should NASA and the nation make to achieve the goals of NASA

  19. NASA's Role in Aeronautics: A Workshop. Volume 6: Aeronautical research

    NASA Technical Reports Server (NTRS)

    1981-01-01

    While each aspect of its aeronautical technology program is important to the current preeminence of the United States in aeronautics, the most essential contributions of NASA derive from its research. Successes and challenges in NASA's efforts to improve civil and military aviation are discussed for the following areas: turbulence, noise, supercritical aerodynamics, computational aerodynamics, fuels, high temperature materials, composite materials, single crystal components, powder metallurgy, and flight controls. Spin offs to engineering and other sciences explored include NASTRAN, lubricants, and composites.

  20. Effect of heat and radio frequency electric field treatments on membrane damage and intracellular leakage of UV-substances of Escherichia coli K-12 in apple juice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The need for a nonthermal intervention technology that can achieve microbial safety without altering nutritional quality of liquid foods led to the development of the radio frequency electric fields (RFEF) process. Previously, we documented formation of surface blebs on Escherichia coli cells treate...

  1. Shroud leakage flow discouragers

    DOEpatents

    Bailey, Jeremy Clyde; Bunker, Ronald Scott

    2002-01-01

    A turbine assembly includes a plurality of rotor blades comprising a root portion, an airfoil having a pressure sidewall and a suction sidewall, and a top portion having a cap. An outer shroud is concentrically disposed about said rotor blades, said shroud in combination with said tip portions defining a clearance gap. At least one circumferential shroud leakage discourager is disposed within the shroud. The leakage discourager(s) increase the flow resistance and thus reduce the flow of hot gas flow leakage for a given pressure differential across the clearance gap to improve overall turbine efficiency.

  2. 14 CFR 77.35 - Aeronautical studies.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aeronautical studies. 77.35 Section 77.35 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRSPACE OBJECTS AFFECTING NAVIGABLE AIRSPACE Aeronautical Studies of Effect of Proposed Construction on Navigable Airspace § 77.35 Aeronautical studies....

  3. Compressibility Effects in Aeronautical Engineering

    NASA Technical Reports Server (NTRS)

    Stack, John

    1941-01-01

    Compressible-flow research, while a relatively new field in aeronautics, is very old, dating back almost to the development of the first firearm. Over the last hundred years, researches have been conducted in the ballistics field, but these results have been of practically no use in aeronautical engineering because the phenomena that have been studied have been the more or less steady supersonic condition of flow. Some work that has been done in connection with steam turbines, particularly nozzle studies, has been of value, In general, however, understanding of compressible-flow phenomena has been very incomplete and permitted no real basis for the solution of aeronautical engineering problems in which.the flow is likely to be unsteady because regions of both subsonic and supersonic speeds may occur. In the early phases of the development of the airplane, speeds were so low that the effects of compressibility could be justifiably ignored. During the last war and immediately after, however, propellers exhibited losses in efficiency as the tip speeds approached the speed of sound, and the first experiments of an aeronautical nature were therefore conducted with propellers. Results of these experiments indicated serious losses of efficiency, but aeronautical engineers were not seriously concerned at the time became it was generally possible. to design propellers with quite low tip. speeds. With the development of new engines having increased power and rotational speeds, however, the problems became of increasing importance.

  4. National Advisory Committee for Aeronautics

    NASA Technical Reports Server (NTRS)

    1938-01-01

    NASA was created from the National Advisory Committee on Aeronautics in 1958. This is a photo of the members of the advisory board of NACA in 1938. NACA was the governmental organization charged with the supervision and conduct of scientific laboratory research in aeronautics. Its laboratories located at Langley Field, Virginia, provide new knowledge underlying the continuous improvement in the performance, efficiency, and safety of American aircraft. At this meeting Dr. Joesph S. Ames, President Emeritus of John Hopkins University, was re-elected Chairman, and Dr. Vannevar Bush, President- elect of the Carnegie Institution of Washington, was elected Vice Chairman. Dr. Ames' re-election as chairman was a recognition of his outstanding contributions to the science of aeronautics. He has been the leading scientific member of the Committee for over twenty-three years and chairman for eleven years. Under his visionary leadership the great laboratories of the N.A.C.A. at Langley Field have been developed. Left to Right: Hon. C. M. Hester, Administrator, Civil Aeronautics Authority Captain S. M. Kraus, U.S.N. Brig. General A. W. Robins, Chief, Materiel Division, Army Air Corps. Dr. L.J. Biggs, Director, National Bureau of Standards Dr. E.P. Warner Dr. Orville Wright Dr. Joesph S. Ames, Chairman Dr. C.J. Abbot, Secretary, Smithsonian Institution J.F. Victory, Secretary Rear Adm. A.B. Cook, U.S.N., Chief, Bureau Aeronautics Authority Dr. Vannevar Bush Dr. J.C. Hunsaker Dr. G.W. Lewis, Director of Aeronautical Research. Absent: Col. Charles A. Lindbergh and Maj. Gen. H. 'Hap' Arnold, Chief, Army Air Corps. One Vacany: U.S. Weather Bureau.

  5. Zero leakage sealings

    NASA Astrophysics Data System (ADS)

    Kotesovec, Bernhard; Steinrück, Herbert

    2010-11-01

    The piston rod of a reciprocating compressor is sealed with elastic cylindrical sealing elements. Across the sealings the pressure drops from the operating pressure to the ambient pressure. The lubrication gap between the elastic sealing and reciprocating piston rod is studied with the aim to find conditions of a leakage free sealing. The flow in the lubrication gap and the elastic deformation of the sealing are determined simultaneously. The net-flow during one cycle of the reciprocating piston rod is calculated. It turns out that maintaining zero leakage is very sensible. Indeed the outbound flow during out-stroke has to be equal the inbound flow during the in-stroke. By prescribing a special shape of the undeformed sealing zero leakage can be attained - at least theoretically for certain operating conditions. It turns out that temperature dependent material data and a model for cavitation is necessary. The model, its numerical implementation and results will be discussed.

  6. Job Prospects for Aeronautical Engineers.

    ERIC Educational Resources Information Center

    Basta, Nicholas

    1985-01-01

    Huge defense budgets and a commercial aircraft comeback are contributing to high demands for aeronautical engineers. Job offers are plentiful and are expected to rise by 41 percent from 1982 to 1995. Federal space programs will provide additional employment opportunities. (DH)

  7. NASA's role in aeronautical research

    NASA Technical Reports Server (NTRS)

    Parker, M.

    1983-01-01

    Past and current research in the aeronautical field conducted by NASA is reviewed. The first national center for aeronautical research, the Langley Memorial Aeronautical Laboratory, was established in 1917 by the then formed National Advisory Committee for Aeronautics (NACA). Two other research centers established later by NACA (Lewis and Ames) were staffed with research cadres from Langley. These three research centers formed the nucleus of NASA when it was established in 1958. Studies conducted today by NASA's research centers include: a concept for commuter-style aircraft, turbofan engines for military supersonic fighter aircraft, strength and durability of man-made fiber materials, and maneuverability problems in high speed aircraft. In addition, at Ames, research is being conducted on short-haul aviation, and short and vertical takeoff while at Lewis studies concentrate on propulsion system and engines. At Langley the emphasis is on basic research, stressing aircraft structure improvements, stall avoidance and noise abatement. Finally, the importance of NASA's educational program is discussed.

  8. 1997 NASA Academy in Aeronautics

    NASA Technical Reports Server (NTRS)

    Andrisani, Dominick, II

    1998-01-01

    The NASA Academy in Aeronautics at the Dryden Flight Research Center (DFRC) was a ten-week summer leadership training program conducted for the first time in the summer of 1997. Funding was provided by a contract between DFRC and Purdue University. Mr. Lee Duke of DFRC was the contract monitor, and Professor Dominick Andrisani was the principal investigator. Five student research associates participated in the program. Biographies of the research associates are given in Appendix 1. Dominick Andrisani served as Dean of the NASA Academy in Aeronautics. NASA Academy in Aeronautics is a unique summer institute of higher learning that endeavors to provide insight into all of the elements that make NASA aeronautical research possible. At the same time the Academy assigns the research associate to be mentored by one of NASA!s best researchers so that they can contribute towards an active flight research program. Aeronautical research and development are an investment in the future, and NASA Academy is an investment in aeronautical leaders of the future. The Academy was run by the Indiana Space Grant Consortium at Purdue in strategic partnership with the National Space Grant College and Fellowship Program. Research associates at the Academy were selected with help from the Space Grant Consortium that sponsored the research associate. Research associate stipend and travel to DFRC were paid by the students' Space Grant Consortium. All other student expenses were paid by the Academy. Since the Academy at DFRC had only five students the opportunity for individual growth and attention was unique in the country. About 30% of the working time and most of the social time of the students were be spent as a "group" or "team." This time was devoted to exchange of ideas, on forays into the highest levels of decision making, and in executing aeronautical research. This was done by interviewing leaders throughout the aerospace industry, seminars, working dinners, and informal

  9. Estimation of leakage rates through flexible membrane liners

    SciTech Connect

    Murray, G.B.; McBean, E.A.; Sykes, J.F.

    1995-12-31

    Leakage rate calculations for both low-permeability soil liners and composite liners using flexible membrane liners (FMLs) overlying low-permeability soil are developed. Latin-Hypercube simulations with uncertainty assigned to the soil liner hydraulic conductivity value and the spatial frequency of FML holes are used to examine the variability in the liner leakage rats. The low-permeability soil hydraulic conductivity is the parameter with the greatest effect on landfill liner leakages rates. Composite liners have a significant impact on reducing leakage rates through the landfill liner.

  10. A Hybrid Satellite-Terrestrial Approach to Aeronautical Communication Networks

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Chomos, Gerald J.; Griner, James H.; Mainger, Steven W.; Martzaklis, Konstantinos S.; Kachmar, Brian A.

    2000-01-01

    Rapid growth in air travel has been projected to continue for the foreseeable future. To maintain a safe and efficient national and global aviation system, significant advances in communications systems supporting aviation are required. Satellites will increasingly play a critical role in the aeronautical communications network. At the same time, current ground-based communications links, primarily very high frequency (VHF), will continue to be employed due to cost advantages and legacy issues. Hence a hybrid satellite-terrestrial network, or group of networks, will emerge. The increased complexity of future aeronautical communications networks dictates that system-level modeling be employed to obtain an optimal system fulfilling a majority of user needs. The NASA Glenn Research Center is investigating the current and potential future state of aeronautical communications, and is developing a simulation and modeling program to research future communications architectures for national and global aeronautical needs. This paper describes the primary requirements, the current infrastructure, and emerging trends of aeronautical communications, including a growing role for satellite communications. The need for a hybrid communications system architecture approach including both satellite and ground-based communications links is explained. Future aeronautical communication network topologies and key issues in simulation and modeling of future aeronautical communications systems are described.

  11. 14 CFR 61.185 - Aeronautical knowledge.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aeronautical knowledge. 61.185 Section 61... Flight Instructors With a Sport Pilot Rating § 61.185 Aeronautical knowledge. (a) A person who is... aeronautical knowledge areas for a recreational, private, and commercial pilot certificate applicable to...

  12. 14 CFR 61.125 - Aeronautical knowledge.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aeronautical knowledge. 61.125 Section 61... Aeronautical knowledge. (a) General. A person who applies for a commercial pilot certificate must receive and... aeronautical knowledge areas of paragraph (b) of this section that apply to the aircraft category and...

  13. 14 CFR 61.105 - Aeronautical knowledge.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aeronautical knowledge. 61.105 Section 61.105 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Private Pilots § 61.105 Aeronautical knowledge. (a) General. A person who...

  14. 14 CFR 61.125 - Aeronautical knowledge.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aeronautical knowledge. 61.125 Section 61.125 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Commercial Pilots § 61.125 Aeronautical knowledge. (a) General. A person...

  15. 14 CFR 61.97 - Aeronautical knowledge.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aeronautical knowledge. 61.97 Section 61.97 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Recreational Pilots § 61.97 Aeronautical knowledge. (a) General. A person...

  16. Aeronautics. America in Space: The First Decade.

    ERIC Educational Resources Information Center

    Anderton, David A.

    The major research and developments in aeronautics during the late 1950's and 1960's are reviewed descriptively with a minimum of technical content. Topics covered include aeronautical research, aeronautics in NASA, The National Advisory Committee for Aeronautics, the X-15 Research Airplane, variable-sweep wing design, the Supersonic Transport…

  17. 14 CFR 61.97 - Aeronautical knowledge.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Aeronautical knowledge. 61.97 Section 61.97 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Recreational Pilots § 61.97 Aeronautical knowledge. (a) General. A person...

  18. 14 CFR 61.125 - Aeronautical knowledge.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Aeronautical knowledge. 61.125 Section 61.125 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Commercial Pilots § 61.125 Aeronautical knowledge. (a) General. A person...

  19. 14 CFR 61.185 - Aeronautical knowledge.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Aeronautical knowledge. 61.185 Section 61... Flight Instructors With a Sport Pilot Rating § 61.185 Aeronautical knowledge. (a) A person who is... aeronautical knowledge areas for a recreational, private, and commercial pilot certificate applicable to...

  20. 14 CFR 61.185 - Aeronautical knowledge.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Aeronautical knowledge. 61.185 Section 61... Flight Instructors With a Sport Pilot Rating § 61.185 Aeronautical knowledge. (a) A person who is... aeronautical knowledge areas for a recreational, private, and commercial pilot certificate applicable to...

  1. 14 CFR 61.185 - Aeronautical knowledge.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Aeronautical knowledge. 61.185 Section 61... Flight Instructors With a Sport Pilot Rating § 61.185 Aeronautical knowledge. (a) A person who is... aeronautical knowledge areas for a recreational, private, and commercial pilot certificate applicable to...

  2. 14 CFR 61.185 - Aeronautical knowledge.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aeronautical knowledge. 61.185 Section 61... Flight Instructors With a Sport Pilot Rating § 61.185 Aeronautical knowledge. (a) A person who is... aeronautical knowledge areas for a recreational, private, and commercial pilot certificate applicable to...

  3. NASA/University Conference on Aeronautics

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The proceedings of a conference on the future of aeronautics are presented. The subjects discussed include the following: (1) aeronautics and the education of the engineer, (2) technical trends in aeronautics, and (3) the role of the university in aeronautics. The technical trends in aeronautics are concerned with aircraft noise control, the effect of the aircraft on the environment, airborne electronics for automated flight, and trends in aircraft design.

  4. Progress Toward National Aeronautics Goals

    NASA Technical Reports Server (NTRS)

    Russo, Carlo J.; Sehra, Arun K.

    1999-01-01

    NASA has made definitive progress towards achieving several bold U.S. goals in aeronautics related to air breathing engines. The advanced technologies developed towards these goals span applications from general aviation to large subsonic and supersonic aircraft. The proof of successful technology development is demonstrated through successful technology transfer to U.S. industry and projected fleet impact. Specific examples of progress are discussed that quantifies the achievement towards these goals. In addition, a more detailed vision for NASA aeronautics is defined and key strategic issues are explored which invite international and national debate and involvement especially in reduced environmental impact for subsonic and supersonic aircraft, dramatic new capabilities in general aviation engines, and reduced development cycle time and costs.

  5. Canadian aeronautical mobile data trials

    NASA Technical Reports Server (NTRS)

    Pedersen, Allister; Pearson, Andrea

    1993-01-01

    This paper describes a series of aeronautical mobile data trials conducted on small aircraft (helicopters and fixed wing) utilizing a low-speed store-and-forward mobile data service. The paper outlines the user requirements for aeronautical mobile satellite communications. 'Flight following' and improved wide-area dispatch communications were identified as high priority requirements. A 'proof-of-concept' trial in a Cessna Skymaster aircraft is described. This trial identified certain development work as essential to the introduction of commercial service including antenna development, power supply modifications and doppler software modifications. Other improvements were also proposed. The initial aeronautical mobile data service available for pre-operational (Beta) trials is outlined. Pre-operational field trials commenced in October 1992 and consisted of installations on a Gralen Communications Inc. Cessna 177 and an Aerospatiale Astar 350 series light single engine helicopter. The paper concludes with a discussion of desirable near term mobile data service developments, commercial benefits, current safety benefits and potential future applications for improved safety.

  6. Flows with tip leakage

    NASA Astrophysics Data System (ADS)

    Moore, John

    The flow development within the tip gap and the flow tip leakage, applying Navier-Stokes codes, are discussed. The loss production, the turbine inefficiency and the heat transfer to the blade tip, are considered. The measurements and calculations used demonstrate features of the flow, such as separation and reattachment on the blade tip, shock formation in the tip gap, and formation and dissipation of tip gap secondary kinetic energy. A procedure for calculating turbine blade tip temperatures is included. The results for a centrifugal compressor show the interaction of the tip leakage and passage flows. The radial blackflow near the shroud wall at low off-design flow rates is considered. The calculations demonstrate the potential use of a computational fluid dynamics code for predicting a centrifugal compressor map.

  7. An aeronautical mobile satellite experiment

    NASA Technical Reports Server (NTRS)

    Jedrey, T. C.; Dessouky, K. I.; Lay, N. E.

    1990-01-01

    The various activities and findings of a NASA/FAA/COMSAT/INMARSAT collaborative aeronautical mobile satellite experiment are detailed. The primary objective of the experiment was to demonstrate and evaluate an advanced digital mobile satellite terminal developed at the Jet Propulsion Laboratory under the NASA Mobile Satellite Program. The experiment was a significant milestone for NASA/JPL, since it was the first test of the mobile terminal in a true mobile satellite environment. The results were also of interest to the general mobile satellite community because of the advanced nature of the technologies employed in the terminal.

  8. Program of Research in Aeronautics

    NASA Technical Reports Server (NTRS)

    1981-01-01

    A prospectus of the educational and research opportunities available at the Joint Institute for Advancement of Flight Sciences, operated at NASA Langley Research Center in conjunction with George Washington University's School of Engineering and Applied Sciences is presented. Requirements of admission to various degree programs are given as well as the course offerings in the areas of acoustics, aeronautics, environmental modelling, materials science, and structures and dynamics. Research facilities for each field of study are described. Presentations and publications (including dissertations and theses) generated by each program are listed as well as faculty members visting scientists and engineers.

  9. Aeronautical record : no. 1 (to June, 1923)

    NASA Technical Reports Server (NTRS)

    1923-01-01

    "...considerations have prompted us to pay special attention to the development of aeronautical industries and aerial navigation as a commercial enterprise and to publish an analytical review of events in the aeronautical world and of the attendant problems."

  10. 14 CFR 61.105 - Aeronautical knowledge.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....105 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED.... (b) Aeronautical knowledge areas. (1) Applicable Federal Aviation Regulations of this chapter that...) Recognition of critical weather situations from the ground and in flight, windshear avoidance, and...

  11. 14 CFR 61.97 - Aeronautical knowledge.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN.... (b) Aeronautical knowledge areas. (1) Applicable Federal Aviation Regulations of this chapter that... using pilotage with the aid of a magnetic compass; (5) Recognition of critical weather situations...

  12. 14 CFR 61.105 - Aeronautical knowledge.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....105 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED.... (b) Aeronautical knowledge areas. (1) Applicable Federal Aviation Regulations of this chapter that...) Recognition of critical weather situations from the ground and in flight, windshear avoidance, and...

  13. 14 CFR 61.125 - Aeronautical knowledge.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....125 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... rating sought. (b) Aeronautical knowledge areas. (1) Applicable Federal Aviation Regulations of this... principles of flight; (4) Meteorology to include recognition of critical weather situations,...

  14. 14 CFR 61.125 - Aeronautical knowledge.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....125 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... rating sought. (b) Aeronautical knowledge areas. (1) Applicable Federal Aviation Regulations of this... principles of flight; (4) Meteorology to include recognition of critical weather situations,...

  15. 76 FR 40753 - NASA Advisory Council; Aeronautics Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-11

    ... SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Meeting AGENCY: National Aeronautics... Committee Act, Public Law 92-463, as amended, the National Aeronautics and Space Administration announces a..., Executive Secretary for the Aeronautics Committee, National Aeronautics and Space......

  16. Electrical leakage detection circuit

    DOEpatents

    Wild, Arthur

    2006-09-05

    A method is provided for detecting electrical leakage between a power supply and a frame of a vehicle or machine. The disclosed method includes coupling a first capacitor between a frame and a first terminal of a power supply for a predetermined period of time. The current flowing between the frame and the first capacitor is limited to a predetermined current limit. It is determined whether the voltage across the first capacitor exceeds a threshold voltage. A first output signal is provided when the voltage across the capacitor exceeds the threshold voltage.

  17. 14 CFR 61.105 - Aeronautical knowledge.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aeronautical knowledge. 61.105 Section 61... Aeronautical knowledge. (a) General. A person who is applying for a private pilot certificate must receive and... knowledge areas of paragraph (b) of this section that apply to the aircraft category and class rating...

  18. NASA's aeronautics research and technology base

    NASA Technical Reports Server (NTRS)

    1979-01-01

    NASA's research technology base in aeronautics is assessed in terms of: (1) US aeronautical technology needs and requirements in the future; (2) objectives of the aeronautics program; (3) magnitude and scope of the program; and (4) research and technology performed by NASA and other research organizations.

  19. Questions & Answers about Aeronautics and Space.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    Answers to 27 questions about aeronautics, space, and the National Aeronautics and Space Administration (NASA) are provided in this pamphlet. Among the topics dealt with in these questions are: costs of the space program; NASA's role in aeronautics; benefits received from the space program; why the United States hasn't developed means of rescuing…

  20. The concept of leakage in threat assessment.

    PubMed

    Meloy, J Reid; O'Toole, Mary Ellen

    2011-01-01

    Leakage in the context of threat assessment is the communication to a third party of an intent to do harm to a target. Third parties are usually other people, but the means of communication vary, and include letters, diaries, journals, blogs, videos on the internet, emails, voice mails, and other social media forms of transmission. Leakage is a type of warning behavior that typically infers a preoccupation with the target, and may signal the research, planning, and implementation of an attack. Nomothetic data suggest that leakage occurs in a majority of cases of attacks on and assassinations of public figures, adult mass murders, adolescent mass murders, and school or campus shootings: very low-frequency, but catastrophic acts of intended and targeted violence. Idiographic or case data illustrate the various permutations of leakage. We discuss the operational importance of the concept, place it in the context of other warning behaviors, emphasize the need for further research, and outline risk management strategies for the mitigation of such acts of violence in both law enforcement and clinical mental health settings. PMID:21710573

  1. Modulation and Synchronization for Aeronautical Telemetry

    NASA Astrophysics Data System (ADS)

    Shaw, Christopher G.

    Aeronautical telemetry systems have historically been implemented with constant envelope modulations like CPM. Shifts in system constraints including reduced available bandwidth and increased throughput demands have caused many in the field to reevaluate traditional methods and design practices. This work examines the costs and benefits of using APSK for aeronautical telemetry instead of CPM. Variable rate turbo codes are used to improve the power efficiency of 16- and 32-APSK. Spectral regrowth in nonlinear power amplifiers when driven by non-constant envelope modulation is also considered. Simulation results show the improved spectral efficiency of this modulation scheme over those currently defined in telemetry standards. Additionally, the impact of transitioning from continuous transmission to burst-mode is considered. Synchronization loops are ineffective in burst-mode communication. Data-aided feedforward algorithms can be used to estimate offsets in carrier phase, frequency, and symbol timing between the transmitter and the receiver. If a data-aided algorithm is used, a portion of the transmitted signal is devoted to a known sequence of pilot symbols. Optimum pilot sequences for the three synchronization parameters are obtained analytically and numerically for different system constraints. The alternating sequence is shown to be optimal given a peak power constraint. Alternatively, synchronization can be accomplished using blind algorithms that do not rely on a priori knowledge of a pilot sequence. If blind algorithms are used, the observation interval can be longer than for data-aided algorithms. There are combinations of pilot sequence length and packet length where data-aided algorithms perform better than blind algorithms and vice versa. The conclusion is that a sequential arrangement of blind algorithms operating over an entire burst performs better than a CRB-achieving data-aided algorithm operating over a short pilot sequence.

  2. Aeronautical Engineering: A Continuing Bibliography. Supplement 421

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP#2000-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles.

  3. Mobile-ip Aeronautical Network Simulation Study

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.; Tran, Diepchi T.

    2001-01-01

    NASA is interested in applying mobile Internet protocol (mobile-ip) technologies to its space and aeronautics programs. In particular, mobile-ip will play a major role in the Advanced Aeronautic Transportation Technology (AATT), the Weather Information Communication (WINCOMM), and the Small Aircraft Transportation System (SATS) aeronautics programs. This report presents the results of a simulation study of mobile-ip for an aeronautical network. The study was performed to determine the performance of the transmission control protocol (TCP) in a mobile-ip environment and to gain an understanding of how long delays, handoffs, and noisy channels affect mobile-ip performance.

  4. Reynolds number influences in aeronautics

    NASA Technical Reports Server (NTRS)

    Bushnell, Dennis M.; Yip, Long P.; Yao, Chung-Sheng; Lin, John C.; Lawing, Pierce L.; Batina, John T.; Hardin, Jay C.; Horvath, Thomas J.; Fenbert, James W.; Domack, Christopher S.

    1993-01-01

    Reynolds number, a measure of the ratio of inertia to viscous forces, is a fundamental similarity parameter for fluid flows and therefore, would be expected to have a major influence in aerodynamics and aeronautics. Reynolds number influences are generally large, but monatomic, for attached laminar (continuum) flow; however, laminar flows are easily separated, inducing even stronger, non-monatomic, Reynolds number sensitivities. Probably the strongest Reynolds number influences occur in connection with transitional flow behavior. Transition can take place over a tremendous Reynolds number range, from the order of 20 x 10(exp 3) for 2-D free shear layers up to the order of 100 x 10(exp 6) for hypersonic boundary layers. This variability in transition behavior is especially important for complex configurations where various vehicle and flow field elements can undergo transition at various Reynolds numbers, causing often surprising changes in aerodynamics characteristics over wide ranges in Reynolds number. This is further compounded by the vast parameterization associated with transition, in that any parameter which influences mean viscous flow development (e.g., pressure gradient, flow curvature, wall temperature, Mach number, sweep, roughness, flow chemistry, shock interactions, etc.), and incident disturbance fields (acoustics, vorticity, particulates, temperature spottiness, even electro static discharges) can alter transition locations to first order. The usual method of dealing with the transition problem is to trip the flow in the generally lower Reynolds number wind tunnel to simulate the flight turbulent behavior. However, this is not wholly satisfactory as it results in incorrectly scaled viscous region thicknesses and cannot be utilized at all for applications such as turbine blades and helicopter rotors, nacelles, leading edge and nose regions, and High Altitude Long Endurance and hypersonic airbreathers where the transitional flow is an innately critical

  5. Duct Leakage Repeatability Testing

    SciTech Connect

    Walker, Iain; Sherman, Max

    2014-01-01

    Duct leakage often needs to be measured to demonstrate compliance with requirements or to determine energy or Indoor Air Quality (IAQ) impacts. Testing is often done using standards such as ASTM E1554 (ASTM 2013) or California Title 24 (California Energy Commission 2013 & 2013b), but there are several choices of methods available within the accepted standards. Determining which method to use or not use requires an evaluation of those methods in the context of the particular needs. Three factors that are important considerations are the cost of the measurement, the accuracy of the measurement and the repeatability of the measurement. The purpose of this report is to evaluate the repeatability of the three most significant measurement techniques using data from the literature and recently obtained field data. We will also briefly discuss the first two factors. The main question to be answered by this study is to determine if differences in the repeatability of these tests methods is sufficient to indicate that any of these methods is so poor that it should be excluded from consideration as an allowed procedure in codes and standards.

  6. Duct Leakage Repeatability Testing

    SciTech Connect

    Walker, Iain; Sherman, Max

    2014-08-01

    The purpose of this report is to evaluate the repeatability of the three most significant measurement techniques for duct leakage using data from the literature and recently obtained field data. We will also briefly discuss the first two factors. The main question to be answered by this study is to determine if differences in the repeatability of these tests methods is sufficient to indicate that any of these methods is so poor that it should be excluded from consideration as an allowed procedure in codes and standards. The three duct leak measurement methods assessed in this report are the two duct pressurization methods that are commonly used by many practitioners and the DeltaQ technique. These are methods B, C and A, respectively of the ASTM E1554 standard. Although it would be useful to evaluate other duct leak test methods, this study focused on those test methods that are commonly used and are required in various test standards, such as BPI (2010), RESNET (2014), ASHRAE 62.2 (2013), California Title 24 (CEC 2012), DOE Weatherization and many other energy efficiency programs.

  7. Multifamily Envelope Leakage Model

    SciTech Connect

    Faakye, Omari; Griffiths, Dianne

    2015-05-08

    “The cost for blower testing is high, because it is labor intensive, and it may disrupt occupants in multiple units. This high cost and disruption deter program participants, and dissuade them from pursuing energy improvements that would trigger air leakage testing, such as improvements to the building envelope.” This statement found in a 2012 report by Heschong Mahone Group for several California interests emphasizes the importance of reducing the cost and complexity of blower testing in multifamily buildings. Energy efficiency opportunities are being bypassed. The cost of single blower testing is on the order of $300. The cost for guarded blower door testing—the more appropriate test for assessing energy savings opportunities—could easily be six times that, and that’s only if you have the equipment and simultaneous access to multiple apartments. Thus, the proper test is simply not performed. This research seeks to provide an algorithm for predicting the guarded blower door test result based upon a single, total blower door test.

  8. 77 FR 61432 - NASA Advisory Council; Aeronautics Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-09

    ... SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Meeting AGENCY: National Aeronautics... Committee Act, Public Law 92-463, as amended, the National Aeronautics and Space Administration announces a... Committee Management Officer, National Aeronautics and Space Administration. BILLING......

  9. 75 FR 41240 - NASA Advisory Council; Aeronautics Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-15

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Meeting AGENCY: National Aeronautics... Committee Act, Public Law 92-463, as amended, the National Aeronautics and Space Administration announces...

  10. 75 FR 50782 - NASA Advisory Council; Aeronautics Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-17

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Meeting AGENCY: National Aeronautics... Committee Act, Public Law 92-463, as amended, the National Aeronautics and Space Administration announces...

  11. 77 FR 38091 - NASA Advisory Council; Aeronautics Committee; Meeting.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-26

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Meeting. AGENCY: National Aeronautics... Committee Act, Public Law 92-463, as amended, the National Aeronautics and Space Administration announces...

  12. 47 CFR 87.279 - Frequencies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 87.279 Section 87.279... Aeronautical Enroute and Aeronautical Fixed Stations Aeronautical Fixed Stations § 87.279 Frequencies. (a) United States (except Alaska). The applicant must request specific frequencies in accordance with §...

  13. 47 CFR 87.279 - Frequencies.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Frequencies. 87.279 Section 87.279... Aeronautical Enroute and Aeronautical Fixed Stations Aeronautical Fixed Stations § 87.279 Frequencies. (a) United States (except Alaska). The applicant must request specific frequencies in accordance with §...

  14. 47 CFR 87.279 - Frequencies.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequencies. 87.279 Section 87.279... Aeronautical Enroute and Aeronautical Fixed Stations Aeronautical Fixed Stations § 87.279 Frequencies. (a) United States (except Alaska). The applicant must request specific frequencies in accordance with §...

  15. 47 CFR 87.279 - Frequencies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Frequencies. 87.279 Section 87.279... Aeronautical Enroute and Aeronautical Fixed Stations Aeronautical Fixed Stations § 87.279 Frequencies. (a) United States (except Alaska). The applicant must request specific frequencies in accordance with §...

  16. Neutrino Leakage and Supernova Explosion

    NASA Astrophysics Data System (ADS)

    Liao, Dao-Bing; Zhang, Miao-Jing; Li, Yan; Pan, Jiang-Hong; Chen, Xiu

    2015-04-01

    In the process of supernova explosion the leakage of neutrinos is very important. Adopting an one-dimensional spherically symmetrical model, and under the different neutrino leakage modes, the explosion processes of type II supernovae with masses of 12 M⊙, 14 M⊙, and 15 M⊙ are simulated numerically. The results indicate that all these different neutrino leakage modes have influences on the supernova collapse, shock propagation, and supernova explosion. The best values of the related parameters which are propitious for the type II supernova explosion are given. In addition, the impacts of the equation of state and the compression modulus on the simulated results are discussed.

  17. 14 CFR 61.97 - Aeronautical knowledge.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aeronautical knowledge. 61.97 Section 61.97... knowledge. (a) General. A person who applies for a recreational pilot certificate must receive and log... knowledge areas of paragraph (b) of this section that apply to the aircraft category and class rating...

  18. Economic analysis of aeronautical research and technology

    NASA Technical Reports Server (NTRS)

    Gellman, A. J.

    1982-01-01

    The appropriateness of government intervention in the civilian market for aeronautics research and technology (R&T) is examined. The economic rationale for government intervention is examined. The conclusion is that the institutional role played by NASA in civilian aeronautics R&T markets is economically justified.

  19. 14 CFR 77.35 - Aeronautical studies.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... physical and electromagnetic radiation effect the proposal may have on the operation of an air navigation... OBJECTS AFFECTING NAVIGABLE AIRSPACE (Eff. until 1-18-11) Aeronautical Studies of Effect of Proposed..., conducts the aeronautical study of the effect of the proposal upon the operation of air...

  20. University/government/industry relations in aeronautics

    NASA Technical Reports Server (NTRS)

    Schairer, G. S.

    1975-01-01

    Methods for improving the relationships between universities, the aircraft industry, and the Government are proposed. The author submits nine specific recommendations aimed at more effective aeronautical engineering education and employment of graduate engineers. The need for improved communication between the organizations which influence the advancement of aeronautical sciences is stressed.

  1. Review of Aeronautical Wind Tunnel Facilities

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The nation's aeronautical wind tunnel facilities constitute a valuable technological resource and make a significant contribution to the global supremacy of U.S. aircraft, both civil and military. At the request of NASA, the National Research Council's Aeronautics and Space Engineering Board organized a commitee to review the state of repair, adequacy, and future needs of major aeronautical wind tunnel facilities in meeting national goals. The comittee identified three main areas where actions are needed to sustain the capability of NASA's aeronautical wind tunnel facilities to support the national aeronautical research and development activities: tunnel maintenance and upgrading, productivity enhancement, and accommodation of new requirements (particularly in hypersonics). Each of these areas are addressed and the committee recommendations for appropriate actions presented.

  2. Time reversal technique for gas leakage detection.

    PubMed

    Maksimov, A O; Polovinka, Yu A

    2015-04-01

    The acoustic remote sensing of subsea gas leakage traditionally uses sonars as active acoustic sensors and hydrophones picking up the sound generated by a leak as passive sensors. When gas leaks occur underwater, bubbles are produced and emit sound at frequencies intimately related to their sizes. The experimental implementation of an acoustic time-reversal mirror (TRM) is now well established in underwater acoustics. In the basic TRM experiment, a probe source emits a pulse that is received on an array of sensors, time reversed, and re-emitted. After time reversal, the resulting field focuses back at the probe position. In this study, a method for enhancing operation of the passive receiving system has been proposed by using it in the regime of TRM. Two factors, the local character of the acoustic emission signal caused by the leakage and a resonant nature of the bubble radiation at their birth, make particularly effective scattering with the conjugate wave (CW). Analytical calculations are performed for the scattering of CW wave on a single bubble when CW is formed by bubble birthing wail received on an array, time reversed, and re-emitted. The quality of leakage detection depends on the spatio-temporal distribution of ambient noise. PMID:25920866

  3. A geostationary satellite system for mobile multimedia applications using portable, aeronautical and mobile terminals

    NASA Technical Reports Server (NTRS)

    Losquadro, G.; Luglio, M.; Vatalaro, F.

    1997-01-01

    A geostationary satellite system for mobile multimedia services via portable, aeronautical and mobile terminals was developed within the framework of the Advanced Communications Technology Service (ACTS) programs. The architecture of the system developed under the 'satellite extremely high frequency communications for multimedia mobile services (SECOMS)/ACTS broadband aeronautical terminal experiment' (ABATE) project is presented. The system will be composed of a Ka band system component, and an extremely high frequency band component. The major characteristics of the space segment, the ground control station and the portable, aeronautical and mobile user terminals are outlined.

  4. TWO NEW DUCT LEAKAGE TESTS

    SciTech Connect

    ANDREWS,J.W.

    1998-12-01

    Two variations on the tests for duct leakage currently embodied in ASHRAE Standard 152P (Method of Test for Determining the Design and Seasonal Efficiencies of Residential Thermal Distribution Systems) are presented. Procedures are derived for calculating supply and return duct leakage to/from outside using these new variations. Results of these tests are compared with the original ones in Standard 152P on the basis of data collected in three New York State homes.

  5. Two New Duct Leakage Tests

    SciTech Connect

    Andrews, J.W.

    1998-12-01

    Two variations on the tests for duct leakage currently embodied in ASHRAE Standard 152P (Method of Test for Determining the Design and Seasonal Efficiencies of Residential Thermal Distribution Systems) are presented. Procedures are derived for calculating supply and return duct leakage to/from outside using these new variations. Results of these tests are compared with the original ones in Standard 152P on the basis of data collected in three New York State homes.

  6. Aeronautical Engineering: A Continuing Bibliography. Supplment 385

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-1998-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract.

  7. 14 CFR 61.155 - Aeronautical knowledge.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....155 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... knowledge areas. (1) Applicable Federal Aviation Regulations of this chapter that relate to airline... aircraft's flight characteristics and performance in normal and abnormal flight regimes; (11) Human...

  8. 14 CFR 61.155 - Aeronautical knowledge.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....155 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... knowledge areas. (1) Applicable Federal Aviation Regulations of this chapter that relate to airline... aircraft's flight characteristics and performance in normal and abnormal flight regimes; (11) Human...

  9. 14 CFR 61.155 - Aeronautical knowledge.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....155 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... knowledge areas. (1) Applicable Federal Aviation Regulations of this chapter that relate to airline... aircraft's flight characteristics and performance in normal and abnormal flight regimes; (11) Human...

  10. 14 CFR 61.155 - Aeronautical knowledge.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....155 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... knowledge areas. (1) Applicable Federal Aviation Regulations of this chapter that relate to airline... aircraft's flight characteristics and performance in normal and abnormal flight regimes; (11) Human...

  11. NASA Aeronautics Showcased at Balloon Fiesta

    NASA Video Gallery

    Visitors at the 2010 International Balloon Fiesta in Albuquerque, N.M., got visual stimulation from hundreds of colorful hot-air balloons soaring skyward, but also learned about NASA's aeronautics ...

  12. NASA Aeronautics: A New Strategic Vision

    NASA Video Gallery

    The aviation landscape is shifting. Emerging global trends are creating challenges that are changing the face of aviation for the next 20-40 years. How is NASA Aeronautics responding? With a new st...

  13. Astronautics and aeronautics, 1977: A chronology

    NASA Technical Reports Server (NTRS)

    Ritchie, E. H.

    1986-01-01

    This publication is a chronology of events during the year 1977 in the fields of aeronautical and space research, development, activity, and policy. It includes appendixes, an index, and illustrations. Chronological entries list sources for further inquiry.

  14. Center for Aeronautics and Space Information Sciences

    NASA Technical Reports Server (NTRS)

    Flynn, Michael J.

    1992-01-01

    This report summarizes the research done during 1991/92 under the Center for Aeronautics and Space Information Science (CASIS) program. The topics covered are computer architecture, networking, and neural nets.

  15. Costs and Benefits of Advanced Aeronautical Technology

    NASA Technical Reports Server (NTRS)

    Bobick, J. C.; Denny, R. E.

    1983-01-01

    Programs available from COSMIC used to evaluate economic feasibility of applying advanced aeronautical technology to civil aircraft of future. Programs are composed of three major models: Fleet Accounting Module, Airframe manufacturer Module, and Air Carrier Module.

  16. Aeronautics and space report of the President

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This report describes the activities and accomplishments of all agencies of the United States in the fields of aeronautics and space science during FY 1994. Activity summaries are presented for the following areas: space launch activities, space science, space flight and space technology, space communications, aeronuatics, and studies of the planet Earth. Several appendices providing data on U.S. launch activities, the Federal budget for space and aeronautics, remote sensing capabilities, and space policy are included.

  17. Aeronautical Engineering: A Continuing Bibliography with Indexes

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This bibliography lists 193 reports, journal articles, and other documents introduced in the NASA scientific and technical system in Aug. 1995. Subject coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles

  18. Understanding instrumental Stokes leakage in Murchison Widefield Array polarimetry

    NASA Astrophysics Data System (ADS)

    Sutinjo, A.; O'Sullivan, J.; Lenc, E.; Wayth, R. B.; Padhi, S.; Hall, P.; Tingay, S. J.

    2015-01-01

    This paper offers an electromagnetic, more specifically array theory, perspective on understanding strong instrumental polarization effects for planar low-frequency "aperture arrays" with the Murchison Widefield Array (MWA) as an example. A long-standing issue that has been seen here is significant instrumental Stokes leakage after calibration, particularly in Stokes Q at high frequencies. A simple model that accounts for interelement mutual coupling is presented which explains the prominence of Q leakage seen when the array is scanned away from zenith in the principal planes. On these planes, the model predicts current imbalance in the X (E-W) and Y (N-S) dipoles and hence the Q leakage. Although helpful in concept, we find that this model is inadequate to explain the full details of the observation data. This finding motivates further experimentation with more rigorous models that account for both mutual coupling and embedded element patterns. Two more rigorous models are discussed: the "full" and "average" embedded element patterns. The viability of the full model is demonstrated by simulating current MWA practice of using a Hertzian dipole model as a Jones matrix estimate. We find that these results replicate the observed Q leakage to approximately 2 to 5%. Finally, we offer more direct indication for the level of improvement expected from upgrading the Jones matrix estimate with more rigorous models. Using the average embedded pattern as an estimate for the full model, we find that Q leakage of a few percent is achievable.

  19. Civilian Aeronautical Futures - The Responsibly Imaginable

    NASA Technical Reports Server (NTRS)

    Bushnell, Dennis M.

    2006-01-01

    Since 1940 Aeronautics has had an immense impact upon Global Human lifestyles and affairs - in both the Civilian and Military arenas. During this period Long distance Train and Ship passenger transport were largely supplanted by Air Travel and Aviation assumed a dominant role in warfare. The early 1940 s to the mid 1970 s was a particularly productive period in terms of Aeronautical Technology. What is interesting is that, since the mid 1970 s, the rate of Aeronautical Technological Progress has been far slower, the basic technology in nearly all of our current Aero Systems dates from the mid 70 s or earlier. This is especially true in terms of Configuration Aerodynamics, Aeronautics appears to have "settled" on the 707, double delta and rotary wing as the approach of choice for Subsonic long haul, supersonic cruise and VTOL respectively. Obviously there have been variants and some niche digression from this/these but in the main Aeronautics, particularly civilian Aeronautics, has become a self-professed "mature", Increasingly "Commodity", Industry. The Industry is far along an existing/deployed technology curve and focused, now for decades, on incremental/evolutionary change - largely Appliers vs. developers of technology. This is, of course, in sharp contrast to the situation in the early-to-later 20th century where Aeronautics was viewed as A Major Technological Engine, much the way IT/Bio/Nano/Energetics/Quantum Technologies are viewed today. A search for Visionary Aeronautical "Futures" papers/projections indicates a decided dearth thereof over the last 20 plus years compared to the previous quarter Century. Aeronautics is part of Aerospace and Aerospace [including Aeronautics] has seen major cutbacks over the last decades. Some numbers for the U.S. Aerospace Industry serve as examples. Order of 600,000 jobs lost, with some 180,000 more on the block over the next 10 years. Approximately 25% of the Aerospace workforce is eligible to retire and the average

  20. Robust characterization of leakage errors

    NASA Astrophysics Data System (ADS)

    Wallman, Joel J.; Barnhill, Marie; Emerson, Joseph

    2016-04-01

    Leakage errors arise when the quantum state leaks out of some subspace of interest, for example, the two-level subspace of a multi-level system defining a computational ‘qubit’, the logical code space of a quantum error-correcting code, or a decoherence-free subspace. Leakage errors pose a distinct challenge to quantum control relative to the more well-studied decoherence errors and can be a limiting factor to achieving fault-tolerant quantum computation. Here we present a scalable and robust randomized benchmarking protocol for quickly estimating the leakage rate due to an arbitrary Markovian noise process on a larger system. We illustrate the reliability of the protocol through numerical simulations.

  1. Leakage currents in SOI MOSFETS

    SciTech Connect

    Annamala, N.K.; Biwer, M.C.

    1988-12-01

    Total dose response of both NMOS and PMOS FETs fabricated on SOI substrates was studied. Two types of back-channel leakage currents were identified. A back-channel leakage due to MOSFET action uses the substrate bias as the gate bias. The other component is due to soft reverse characteristics of the body-drain junction. The back-channel leakage due to MOSFET action varies with the substrate bias and hence varies with irradiation due to threshold voltage shift. The soft reverse characteristics are a function of drain-body voltage and hence vary with substrate bias and irradiation. I-V characteristics and subthreshold currents of both front and back channels as a function of total dose were obtained.

  2. 47 CFR 87.263 - Frequencies.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequencies. 87.263 Section 87.263 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AVIATION SERVICES Aeronautical Enroute and Aeronautical Fixed Stations Aeronautical Enroute Stations § 87.263 Frequencies. (a) Domestic VHF service. (1)...

  3. Air-leakage control manual

    SciTech Connect

    Maloney, J.

    1991-05-01

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

  4. Air-Leakage Control Manual.

    SciTech Connect

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

    1991-05-01

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

  5. Emerging Options and Opportunities in Civilian Aeronautics

    NASA Technical Reports Server (NTRS)

    Bushnell, Dennis M.

    2012-01-01

    This paper addresses the major problems/issues with civilian aeronautics going forward, the contextual ongoing technology revolutions, the several emerging civilian aeronautical "Big Ideas" and associated enabling technological approaches. The ongoing IT Revolution is increasingly providing, as 5 senses virtual presence/reality becomes available, along with Nano/Molecular Manufacturing, virtual alternatives to Physical transportation for both people and goods. Paper examines the potential options available to aeronautics to maintain and perhaps grow "market share" in the context of this evolving competition. Many of these concepts are not new, but the emerging technology landscape is enhancing their viability and marketability. The concepts vary from the "interesting" to the truly revolutionary and all require considerable research. Paper considers the speed range from personal/general aviation to supersonic transports and technologies from energetics to fabrication.

  6. Aeronautical Engineering: A Continuing Bibliography with Indexes

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This supplemental issue of Aeronautical Engineering: A Continuing Bibliography with Indexes lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes-subject and author are included after the abstract section.

  7. Aeronautical Engineering: A Continuing Bibliography with Indexes

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-1999-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes-subject and author are included after the abstract section.

  8. Aeronautics and space report of the President: 1981 activities

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Achievements in the aeronautics and space program by function are summarized. Activities in communications, Earth's resources and environment, space science, space transportation, international activities, and aeronautics are included.

  9. Wireless Sensor Applications in Extreme Aeronautical Environments

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2013-01-01

    NASA aeronautical programs require rigorous ground and flight testing. Many of the testing environments can be extremely harsh. These environments include cryogenic temperatures and high temperatures (greater than 1500 C). Temperature, pressure, vibration, ionizing radiation, and chemical exposure may all be part of the harsh environment found in testing. This paper presents a survey of research opportunities for universities and industry to develop new wireless sensors that address anticipated structural health monitoring (SHM) and testing needs for aeronautical vehicles. Potential applications of passive wireless sensors for ground testing and high altitude aircraft operations are presented. Some of the challenges and issues of the technology are also presented.

  10. Langley aeronautics and space test highlights, 1984

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The role of the Langley Research Center is to perform basic and applied research necessary for the advancement of aeronautics and space flight, to generate new and advanced concepts for the accomplishment of related national goals, and to provide research advice, technological support, and assistance to other NASA installations, other government agencies, and industry. Some of the significant tests which were performed during calendar year 1984 in Langley test facilities are highlighted. The broad range of the research and technology activities at the Langley Research Center and the contributions of this work toward maintaining United States leadership in aeronautics and space research are illustrated.

  11. Inmarsat aeronautical mobile satellite system: Internetworking issues

    NASA Technical Reports Server (NTRS)

    Sengupta, Jay R.

    1990-01-01

    The Inmarsat Aeronautical Mobile Satellite System (AMSS) provides air-ground and air-air communications services to aero-mobile users on a global basis. Communicating parties may be connected either directly, or more commonly, via interconnecting networks to the Inmarsat AMSS, in order to construct end-to-end communications circuits. The aircraft earth station (AES) and the aeronautical ground earth station (GES) are the points of interconnection of the Inmarsat AMSS to users, as well as to interconnecting networks. This paper reviews the internetworking aspects of the Inmarsat AMSS, by introducing the Inmarsat AMSS network architecture and services concepts and then discussing the internetwork address/numbering and routing techniques.

  12. 49 CFR 229.59 - Leakage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) Leakage from the main air reservoir and related piping may not exceed an average of 3 pounds per square... shall remain applied at least 5 minutes. (d) Leakage from control air reservoir, related piping,...

  13. 49 CFR 229.59 - Leakage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Leakage from the main air reservoir and related piping may not exceed an average of 3 pounds per square... shall remain applied at least 5 minutes. (d) Leakage from control air reservoir, related piping,...

  14. 47 CFR 87.349 - Frequencies.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Frequencies. 87.349 Section 87.349... Aeronautical Utility Mobile Stations § 87.349 Frequencies. (a) The frequency assigned to an aeronautical... frequency used by the control tower for ground traffic control or by the flight service station...

  15. 47 CFR 87.351 - Frequency changes.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequency changes. 87.351 Section 87.351... Aeronautical Utility Mobile Stations § 87.351 Frequency changes. When the aeronautical utility frequency is... control of unicom frequency) the licensee must submit an application for modification to specify the...

  16. 47 CFR 87.351 - Frequency changes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Frequency changes. 87.351 Section 87.351... Aeronautical Utility Mobile Stations § 87.351 Frequency changes. When the aeronautical utility frequency is... control of unicom frequency) the licensee must submit an application for modification to specify the...

  17. 47 CFR 87.351 - Frequency changes.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Frequency changes. 87.351 Section 87.351... Aeronautical Utility Mobile Stations § 87.351 Frequency changes. When the aeronautical utility frequency is... control of unicom frequency) the licensee must submit an application for modification to specify the...

  18. 47 CFR 87.349 - Frequencies.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequencies. 87.349 Section 87.349... Aeronautical Utility Mobile Stations § 87.349 Frequencies. (a) The frequency assigned to an aeronautical... frequency used by the control tower for ground traffic control or by the flight service station...

  19. 47 CFR 87.349 - Frequencies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 87.349 Section 87.349... Aeronautical Utility Mobile Stations § 87.349 Frequencies. (a) The frequency assigned to an aeronautical... frequency used by the control tower for ground traffic control or by the flight service station...

  20. 47 CFR 87.351 - Frequency changes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequency changes. 87.351 Section 87.351... Aeronautical Utility Mobile Stations § 87.351 Frequency changes. When the aeronautical utility frequency is... control of unicom frequency) the licensee must submit an application for modification to specify the...

  1. 47 CFR 87.349 - Frequencies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Frequencies. 87.349 Section 87.349... Aeronautical Utility Mobile Stations § 87.349 Frequencies. (a) The frequency assigned to an aeronautical... frequency used by the control tower for ground traffic control or by the flight service station...

  2. 47 CFR 87.351 - Frequency changes.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Frequency changes. 87.351 Section 87.351... Aeronautical Utility Mobile Stations § 87.351 Frequency changes. When the aeronautical utility frequency is... control of unicom frequency) the licensee must submit an application for modification to specify the...

  3. Bibliography of Aeronautics, 1920-1921

    NASA Technical Reports Server (NTRS)

    Brockett, Paul

    1925-01-01

    This work covers the literatme published from January 1, 1920, to December 31, 1921, and continues the work of the Smithsonian Institution issued as Volume 55 of the Smithsonian Miscellaneous Collections, which covered the material published prior to June 30, 1909, and the work of Lhe National Advisory Committee for Aeronautics as published in the Bibliography of Aeronautics for the years 1909 to 1916 and 1917 to 1919. As in the Smithsonian volume and in the Bibliography of Aeronautics for the years 1909 to 1916 and 1917 to 1919, citations of the publications of all nations have been included in the languages in which these publications originally appeared. The arrangement is in dictionary form with author and subject entry and one alphabetical arrangement. Detail in the matter of subject reference has been omitted on account of the cost of presentation, but an attempt has been made to give sufficient cross reference for research in special lines. The National Advisory Committee for Aeronautics will next present a bibliography for the year 1922.

  4. Developing a global aeronautical satellite system

    NASA Technical Reports Server (NTRS)

    Dement, Donald K.

    1988-01-01

    Arinc, an airline industry-owned and operated company in the United States, has taken steps toward establishing a global aeronautical satellite communications system. Plans call for initiation of a thin-route data operation in 1989, upgrading to establish voice communications via shared spot-beam transponders carried on other satellites, and deploying a worldwide network using dedicated satellites by 1994.

  5. The history of aeronautical medicine in Venezuela

    NASA Technical Reports Server (NTRS)

    Iriarte, D. R.

    1986-01-01

    The Aerial Medical Service of the Ministry of Transportation and Communications of Venezuela was created on June 1949, and later became the Department of Aeronautical Medicine. Its functions include the medical examinations of future pilots, navigators and flight engineers. The importance of good mental and physical health in all flight and ground personnel to ensure the safety of air travel is discussed.

  6. 14 CFR 61.97 - Aeronautical knowledge.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... using pilotage with the aid of a magnetic compass; (5) Recognition of critical weather situations from... recognition and avoidance of wake turbulence; (7) Effects of density altitude on takeoff and climb performance... airplane single-engine rating; (11) Aeronautical decision making and judgment; and (12) Preflight...

  7. Astronautics and aeronautics, 1985: A chronology

    NASA Technical Reports Server (NTRS)

    Janson, Bette R.

    1988-01-01

    This book is part of a series of annual chronologies of significant events in the fields of astronautics and aeronautics. Events covered are international as well as national, in political as well as scientific and technical areas. This series is an important reference work used by historians, NASA personnel, government agencies, and congressional staffs, as well as the media.

  8. Aeronautical Engineering: A Continuing Bibliography with indexes

    NASA Technical Reports Server (NTRS)

    1984-01-01

    This bibliography lists 426 reports, articles and other documents introduced into the NASA scientific and technical information system in August 1984. Reports are cited in the area of Aeronautical Engineering. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing operation and performance of aircraft (including aircraft engines) and associated components, equipment and systems.

  9. Experiment In Aeronautical-Mobile/Satellite Communication

    NASA Technical Reports Server (NTRS)

    Jedrey, Thomas C.; Lay, Norman E.; Dessouky, Khaled

    1992-01-01

    Report describes study of performance of digital mobile/satellite communication terminals of advanced design intended for use in ground stations and airplanes in aeronautical-mobile service. Study was collaboration of NASA, Federal Aviation Administration (FAA), Communications Satellite Corp. (COMSAT), and International Maritime Satellite System (INMARSAT).

  10. Astronautics and aeronautics, 1974: A chronology

    NASA Technical Reports Server (NTRS)

    Brun, N. L.

    1977-01-01

    The 14th volume in the NASA series of day-by-day records of aeronautical and space events has somewhat narrowed its scope and selectivity in its brief accounts from immediately available, open sources. This year the emphasis is even more directly focused on concrete air and space activities. The text continues to reflect some events in other agencies and countries.

  11. Aeronautical engineering. A continuing bibliography with indexes

    NASA Technical Reports Server (NTRS)

    1982-01-01

    This bibliography lists 326 reports, articles, and other documents introduced into the NASA scientific and technical information system in January 1982. Topics on aeronautical engineering and aerodynamics such as flight control systems, avionics, computer programs, computational fluid dynamics and composite structures are covered.

  12. Astronautics and aeronautics, 1976. A chronology

    NASA Technical Reports Server (NTRS)

    Ritchie, E. H.

    1984-01-01

    A chronology of events concerning astronautics and aeronautics for the year 1976 is presented. Some of the many and varied topics include the aerospace industry, planetary exploration, space transportation system, defense department programs, politics, and aerospace medicine. The entries are organized by the month and presented in a news release format.

  13. Astronautics and aeronautics, 1978: A chronology

    NASA Technical Reports Server (NTRS)

    Janson, Bette R.

    1986-01-01

    This is the 18th in a series of annual chronologies of significant events in the fields of astronautics and aeronautics. Events covered are international as well as national and political as well as scientific and technical. This series is a reference work for historians, NASA personnel, government agencies, congressional staffs, and the media.

  14. Ensuring US National Aeronautics Test Capabilities

    NASA Technical Reports Server (NTRS)

    Marshall, Timothy J.

    2010-01-01

    U.S. leadership in aeronautics depends on ready access to technologically advanced, efficient, and affordable aeronautics test capabilities. These systems include major wind tunnels and propulsion test facilities and flight test capabilities. The federal government owns the majority of the major aeronautics test capabilities in the United States, primarily through the National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD). However, changes in the Aerospace landscape, primarily the decrease in demand for testing over the last 20 years required an overarching strategy for management of these national assets. Therefore, NASA established the Aeronautics Test Program (ATP) as a two-pronged strategic initiative to: (1) retain and invest in NASA aeronautics test capabilities considered strategically important to the agency and the nation, and (2) establish a strong, high level partnership with the DoD. Test facility utilization is a critical factor for ATP because it relies on user occupancy fees to recover a substantial part of the operations costs for its facilities. Decreasing utilization is an indicator of excess capacity and in some cases low-risk redundancy (i.e., several facilities with basically the same capability and overall low utilization). However, low utilization does not necessarily translate to lack of strategic importance. Some facilities with relatively low utilization are nonetheless vitally important because of the unique nature of the capability and the foreseeable aeronautics testing needs. Unfortunately, since its inception, the customer base for ATP has continued to shrink. Utilization of ATP wind tunnels has declined by more than 50% from the FY 2006 levels. This significant decrease in customer usage is attributable to several factors, including the overall decline in new programs and projects in the aerospace sector; the impact of computational fluid dynamics (CFD) on the design, development, and research

  15. Conversion of the Aeronautics Interactive Workstation

    NASA Technical Reports Server (NTRS)

    Riveras, Nykkita L.

    2004-01-01

    This summer I am working in the Educational Programs Office. My task is to convert the Aeronautics Interactive Workstation from a Macintosh (Mac) platform to a Personal Computer (PC) platform. The Aeronautics Interactive Workstation is a workstation in the Aerospace Educational Laboratory (AEL), which is one of the three components of the Science, Engineering, Mathematics, and Aerospace Academy (SEMAA). The AEL is a state-of-the-art, electronically enhanced, computerized classroom that puts cutting-edge technology at the fingertips of participating students. It provides a unique learning experience regarding aerospace technology that features activities equipped with aerospace hardware and software that model real-world challenges. The Aeronautics Interactive Workstation, in particular, offers a variety of activities pertaining to the history of aeronautics. When the Aeronautics Interactive Workstation was first implemented into the AEL it was designed with Macromedia Director 4 for a Mac. Today it is being converted to Macromedia DirectorMX2004 for a PC. Macromedia Director is the proven multimedia tool for building rich content and applications for CDs, DVDs, kiosks, and the Internet. It handles the widest variety of media and offers powerful features for building rich content that delivers red results, integrating interactive audio, video, bitmaps, vectors, text, fonts, and more. Macromedia Director currently offers two programmingkripting languages: Lingo, which is Director's own programmingkripting language and JavaScript. In the workstation, Lingo is used in the programming/scripting since it was the only language in use when the workstation was created. Since the workstation was created with an older version of Macromedia Director it hosted significantly different programming/scripting protocols. In order to successfully accomplish my task, the final product required correction of Xtra and programming/scripting errors. I also had to convert the Mac platform

  16. "Geyser" leakage on fluorescein angiography.

    PubMed

    Levy, Jaime; Fagan, Xavier J; Lifshitz, Tova; Schneck, Marina

    2013-01-01

    An 82-year-old patient with diabetes was followed up due to moderate nonproliferative diabetic retinopathy with macular edema in the right eye. Visual acuity was 6/36. Focal macular laser was conducted (A). Three years later, the patient presented with blurry vision in the right eye. Visual acuity was 3/60. Vitreous hemorrhage was observed (B), and neovascularization of the disc was suspected (C). Fluorescein angiography (D, mid venous phase; E-F, recirculation phase) confirmed neovascularization of the disc and depicted a striking vertical leakage. Panretinal photocoagulation was started. Possible explanations for the "geyser" leakage may be either a partial posterior vitreous detachment allowing the fluorescein to track upwards but not elsewhere or a pocket of syneretic vitreous allowing the fluorescein passage in which to diffuse, much like the passage the blood would have taken. PMID:24548789

  17. 78 FR 69885 - NASA Advisory Council; Aeronautics Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-21

    ... SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Meeting AGENCY: National Aeronautics... meeting of the Aeronautics Committee of the NASA Advisory Council. This Committee reports to the NAC. The... for the Aeronautics Committee, NASA Headquarters, Washington, DC 20546, (202) 358-0566, or...

  18. 14 CFR 63.37 - Aeronautical experience requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Aeronautical experience requirements. 63.37 Section 63.37 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: FLIGHT CREWMEMBERS OTHER THAN PILOTS Flight Engineers § 63.37 Aeronautical experience requirements. (a) Except...

  19. NASA's Role in Aeronautics: A Workshop. Volume I--Summary.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Assembly of Engineering.

    The central task of the workshop summarized in this report was to examine the relationship of the National Aeronautics and Space Administration's (NASA's) aeronautical research capabilities to the state of U.S. aviation and to make recommendations about NASA's future roles in aeronautics. Topics include NASA's role in: (1) aeronautics research and…

  20. Future Aeronautical Communication Infrastructure Technology Investigation

    NASA Technical Reports Server (NTRS)

    Gilbert, Tricia; Jin, Jenny; Bergerm Jason; Henriksen, Steven

    2008-01-01

    This National Aeronautics and Space Administration (NASA) Contractor Report summarizes and documents the work performed to investigate technologies that could support long-term aeronautical mobile communications operating concepts for air traffic management (ATM) in the timeframe of 2020 and beyond, and includes the associated findings and recommendations made by ITT Corporation and NASA Glenn Research Center to the Federal Aviation Administration (FAA). The work was completed as the final phase of a multiyear NASA contract in support of the Future Communication Study (FCS), a cooperative research and development program of the United States FAA, NASA, and EUROCONTROL. This final report focuses on an assessment of final five candidate technologies, and also provides an overview of the entire technology assessment process, including final recommendations.

  1. Langley aeronautics and space test highlights, 1983

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The role of the Langley Research Center is to perform basic and applied research necessary for the advancement of aeronautics and space flight, to generate new and advanced concepts for the accomplishment of related national goals, and to provide research advice, technological support, and assistance to other NASA installations, other government agencies, and industry. Some of the significant tests which were performed during calendar year 1983 in Langley test facilities, a number of which are unique in the world are highlighted. Both the broad range of the research and technology activities at the Langley Research Center and the contributions of this work toward maintaining United States leadership in aeronautics and space research are illustrated.

  2. Aeronautic Instruments. Section II : Altitude Instruments

    NASA Technical Reports Server (NTRS)

    Mears, A H; Henrickson, H B; Brombacher, W G

    1923-01-01

    This report is Section two of a series of reports on aeronautic instruments (Technical Report nos. 125 to 132, inclusive). This section discusses briefly barometric altitude determinations, and describes in detail the principal types of altimeters and barographs used in aeronautics during the recent war. This is followed by a discussion of performance requirements for such instruments and an account of the methods of testing developed by the Bureau of Standards. The report concludes with a brief account of the results of recent investigations. For accurate measurements of altitude, reference must also be made to thermometer readings of atmospheric temperature, since the altitude is not fixed by atmospheric pressure alone. This matter is discussed in connection with barometric altitude determination.

  3. World-wide aeronautical satellite communications

    NASA Technical Reports Server (NTRS)

    Wood, Peter; Smith, Keith

    1988-01-01

    INMARSAT decided to expand the spectrum covered by its new generation of satellites, INMARSAT-2, to include 1 MHz (subsequently increased to 3 MHz) of the spectrum designed for aeronautical use. It began a design study that led to the specifications for the system that is now being implemented. Subsequently, INMARSAT awarded contracts for the design of avionics and high gain antennas to a number of manufactures, while several of the signatories that provide ground equipment for communicating with the INMARSAT satellites are modifying their earth stations to work with the avionic equipment. As a resullt of these activities, a world-wide aeronautical satellite system supporting both voice and data will become operational in 1989.

  4. Aeronautics and Space Report of the President

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The years 1989 to 1990 activities are reported including human space flight, unmanned expendable launch vehicles, space science and applications, space communications operations, space research and technology, and aeronautics research and technology. Contributions made by the 14 participating government organizations are outline. Each organization's aeronautics and/or space activities for the year are presented. The organizations involved include: (1) NASA; (2) Dept. of Defense; (3) Dept. of Commerce; (4) Dept. of Energy; (5) Dept. of the Interior; (6) Dept. of Agriculture; (7) Federal Communications Commission; (8) Dept. of Transportation; (9) Environmental Protection Agency; (10) National Science Foundation; (11) Smithsonian Institution; (12) Dept. of State; (13) Arms Control and Disarmament; and (14) United States Information Agency.

  5. Aeronautics and Space Report of the President

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Nineteen eighty-eight marked the United States' return to space flight with two successful space shuttle launches in September and December, as well as six successful expendable rocket launches. Meanwhile, many other less spectacular but important contributions were made in aeronautics and space by the 14 participating government organizations. Each organization's aeronautics and/or space activities for the year are presented. The organizations involved include: (1) NASA; (2) Department of Defense; (3) Department of Commerce; (4) Department of Energy; (5) Department of the Interior; (6) Department of Agriculture; (7) Federal Communications Commission; (8) Department of Transportation; (9) Environmental Protection Agency; (10) National Science Foundation; (11) Smithsonian Institution; (12) Department of State; (13) Arms Control and Disarmament Agency; and (14) United States Information Agency.

  6. Future directions in aeronautical research and technology

    NASA Technical Reports Server (NTRS)

    Bower, R. E.

    1978-01-01

    The aeronautical R & D effort in NASA is discussed with emphasis on those areas where major needs and opportunities exist. In aerodynamics, areas selected for discussion include computational aerodynamics, transonic test techniques, high Reynolds number research, skin friction drag reduction, and propulsive lift. In propulsion, consideration is given to the areas of fuel-efficient subsonic propulsion, variable-flow engines, hypersonic propulsion, alternate fuels, and aircraft noise reduction. Consideration is also given to the utilization of advanced composites and integrated avionic systems.

  7. Smart Aeronautical Chart Management System Design

    NASA Astrophysics Data System (ADS)

    Pakdil, M. E.; Celik, R. N.; Kaya, Ö.; Konak, Y. C.; Guney, C.

    2015-10-01

    Civil aviation is developing rapidly, and the number of domestic and international operations is increasing exponentially every year than the previous one. Airline companies with increased air traffic and the number of passengers increase the demand of new aircrafts. An aircraft needs not only fuel but also pilot and aeronautical information (charts, digital navigation information, flight plan, and etc.) to perform flight operation. One of the most important components in aeronautical information is the terminal chart. Authorized institution in every state is responsible to publish their terminal charts for certain periods. Although these charts are produced in accordance with ICAO's Annex 4 and Annex 15, cartographic representation and page layout differs in each state's publication. This situation makes difficult to read them by pilots. In this paper, standard instrument departure (SID) charts are analysed to produce by use of cutting-edge and competitive technologies instead of classical computer-aided drawing and vector based graphic applications that are currently used by main chart producers. The goal is to design efficient and commercial chart management system that is able to produce aeronautical charts with same cartographic representation for all states.

  8. Interference Analysis for an Aeronautical Mobile Airport Communications System

    NASA Technical Reports Server (NTRS)

    Wilson, Jeffrey D.; Kerczewski, Robert J.

    2011-01-01

    The next generation of aeronautical communications for airport surface applications has been identified through a NASA research program and an international collaborative future communications study. The result, endorsed by both the United States and European regulatory agencies is called AeroMACS (Aeronautical Mobile Airport Communications System) and is based upon the IEEE 802.16e mobile wireless standard. Coordinated efforts to develop appropriate aviation standards for the AeroMACS system are now underway within RTCA (United States) and Eurocae (Europe). AeroMACS will be implemented in a recently allocated frequency band, 5091-5150 MHz. As this band is also occupied by fixed satellite service uplinks, AeroMACS must be designed to avoid interference with this incumbent service. The aspects of AeroMACS operation that present potential interference to the fixed satellite service are under analysis in order to enable the definition of standards that assure that such interference will be avoided. The NASA Glenn Research Center has been involved in this analysis, and the first results of modeling and simulation efforts directed at this analysis are the subject of this presentation.

  9. Interference Analysis for an Aeronautical Mobile Airport Communications System

    NASA Technical Reports Server (NTRS)

    Wilson, Jeffrey D.; Kercewski, Robert J.

    2010-01-01

    The next generation of aeronautical communications for airport surface applications has been identified through a NASA research program and an international collaborative future communications study. The result, endorsed by both the United States and European regulatory agencies is called AeroMACS (Aeronautical Mobile Airport Communications System) and is based upon the IEEE 802.16e mobile wireless standard. Coordinated efforts to develop appropriate aviation standards for the AeroMACS system are now underway within RTCA (United States) and Eurocae (Europe). AeroMACS will be implemented in a recently allocated frequency band, 5091- 5150 MHz. As this band is also occupied by fixed satellite service uplinks, AeroMACS must be designed to avoid interference with this incumbent service. The aspects of AeroMACS operation that present potential interference to the fixed satellite service are under analysis in order to enable the definition of standards that assure that such interference will be avoided. The NASA Glenn Research Center has been involved in this analysis, and the first results of modeling and simulation efforts directed at this analysis are the subject of this paper.12

  10. Can paternal leakage maintain sexually antagonistic polymorphism in the cytoplasm?

    PubMed Central

    Kuijper, B; Lane, N; Pomiankowski, A

    2015-01-01

    A growing number of studies in multicellular organisms highlight low or moderate frequencies of paternal transmission of cytoplasmic organelles, including both mitochondria and chloroplasts. It is well established that strict maternal inheritance is selectively blind to cytoplasmic elements that are deleterious to males – ’mother's curse’. But it is not known how sensitive this conclusion is to slight levels of paternal cytoplasmic leakage. We assess the scope for polymorphism when individuals bear multiple cytoplasmic alleles in the presence of paternal leakage, bottlenecks and recurrent mutation. When fitness interactions among cytoplasmic elements within an individual are additive, we find that sexually antagonistic polymorphism is restricted to cases of strong selection on males. However, when fitness interactions among cytoplasmic elements are nonlinear, much more extensive polymorphism can be supported in the cytoplasm. In particular, mitochondrial mutants that have strong beneficial fitness effects in males and weak deleterious fitness effects in females when rare (i.e. ’reverse dominance’) are strongly favoured under paternal leakage. We discuss how such epistasis could arise through preferential segregation of mitochondria in sex-specific somatic tissues. Our analysis shows how paternal leakage can dampen the evolution of deleterious male effects associated with predominant maternal inheritance of cytoplasm, potentially explaining why ’mother's curse’ is less pervasive than predicted by earlier work. PMID:25653025

  11. Lidar technologies application to leakage detection in oil product pipelines

    NASA Astrophysics Data System (ADS)

    Petoukhov, Valery M.; Petoukhova, Zaytuna K.; Akhtiamov, Rishad A.; Il'in, German I.; Morozov, Oleg G.; Pol'ski, Yuri E.

    1999-02-01

    Most of oil product pipelines have a design life from 20 till 25 years. The first attributes of their destruction are leakage of oil products. In our paper we try to discuss advantages and disadvantages of one of the main nondestructive techniques to oil product pipelines testing-- lidar technologies and its application to leakage detection. We consider applications of two basical lidars--IR-cw--LFM lidar (DIAL-system) for methane determining and pulsed lidar based on YAG:Nd3+ laser for registration of liquid oil products fluoristation. Set-ups for both lidars were made in Tupolev Kazan State Technical University and were used on the area of Sredne-Volgsk TransNefteProduct oil company for pipelines testing. Theoretical considerations and experimental results are presented. Some technical problems of specified lidars and their decisions are discussed. Particularly we present two frequency technique for He-Ne-DIAL-system and peculiarities of pumping source with high repetition range for pulsed laser. Its allow to improve characteristics of lidars. Possibilities of computerized leak detection system based on two specified lidars are discussed. It is shown that system can analyze leakage of different oil products, can determine leakage location (the second function of lidars-laser locator), can evaluate degree of damages. The structure of system and its peculiarities are shown.

  12. Graduate engineering research participation in aeronautics

    NASA Technical Reports Server (NTRS)

    Roberts, A. S., Jr.

    1986-01-01

    The Aeronautics Graduate Research Program commenced in 1971, with the primary goal of engaging students who qualified for regular admission to the Graduate School of Engineering at Old Dominion University in a graduate engineering research and study program in collaboration with NASA Langley Research Center, Hampton, Virginia. The format and purposes of this program are discussed. Student selection and program statistics are summarized. Abstracts are presented in the folowing areas: aircraft design, aerodynamics, lift/drag characteristics; avionics; fluid mechanics; solid mechanics; instrumentation and measurement techniques; thermophysical properties experiments; large space structures; earth orbital dynamics; and environmental engineering.

  13. The K-8 Aeronautics Internet Textbook

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Efforts were focused on web site migration, from UC (University of California) Davis to the National Business Aviation Association's (NBAA) web site. K8AIT (K-8 Aeronautics Internet Textbook), which has remained an unadvertised web site, receives almost two million hits per month. Project continuation funding with the National Business Aviation Association is being pursued. A Memorandum of Understanding (MOU) between NASA Ames LTP (Learning Technologies Project) and Cislunar has been drafted and approved by NASA's legal department. Additional web content on space flight and the Wright brothers has been added in English and Spanish.

  14. NASA Aeronautics: Research and Technology Program Highlights

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This report contains numerous color illustrations to describe the NASA programs in aeronautics. The basic ideas involved are explained in brief paragraphs. The seven chapters deal with Subsonic aircraft, High-speed transport, High-performance military aircraft, Hypersonic/Transatmospheric vehicles, Critical disciplines, National facilities and Organizations & installations. Some individual aircraft discussed are : the SR-71 aircraft, aerospace planes, the high-speed civil transport (HSCT), the X-29 forward-swept wing research aircraft, and the X-31 aircraft. Critical disciplines discussed are numerical aerodynamic simulation, computational fluid dynamics, computational structural dynamics and new experimental testing techniques.

  15. Solar energy and the aeronautics industry. Thesis

    NASA Technical Reports Server (NTRS)

    Benedek, L.

    1985-01-01

    An introduction to the physical aspects of solar energy, incidental energy and variations in solar flux is presented, along with an explanation of the physical principles of obtaining solar energy. The history of the application of solar energy to aeronautics, including the Gossamer Penguin and the Solar Challenger is given. Finally, an analysis of the possibilities of using a reaction motor with hybrid propulsion combining solar energy with traditional fuels as well as calculations of the proposed cycle and its mode of operation are given.

  16. MSAT aeronautical mobile satellite communications terminal development

    NASA Technical Reports Server (NTRS)

    Sutherland, C. A.; Sydor, J. T.

    1995-01-01

    CAL has undertaken the development of a new aeronautical mobile terminal for the North American MSAT market. The terminal is to meet the MSAT standard and is aimed in particular at the 300,000 general aviation and business aircraft in North America. The terminals are therefore relatively low cost and small in size when compared to those currently being produced for larger airline aircraft. The terminal incorporates a top mounted mechanical steered antenna and a unique antenna steering subsystem. An overview of the terminal design is presented.

  17. Graduate engineering research participation in aeronautics

    NASA Technical Reports Server (NTRS)

    Roberts, A. S., Jr.

    1984-01-01

    Graduate student engineering research in aeronautics at Old Dominion University is surveyed. Student participation was facilitated through a NASA sponsored university program which enabled the students to complete degrees. Research summaries are provided and plans for the termination of the grant program are outlined. Project topics include: Failure modes for mechanically fastened joints in composite materials; The dynamic stability of an earth orbiting satellite deploying hinged appendages; The analysis of the Losipescu shear test for composite materials; and the effect of boundary layer structure on wing tip vortex formation and decay.

  18. Zero leakage separable and semipermanent ducting joints

    NASA Technical Reports Server (NTRS)

    Mischel, H. T.

    1973-01-01

    A study program has been conducted to explore new methods of achieving zero leakage, separable and semipermanent, ducting joints for space flight vehicles. The study consisted of a search of literature of existing zero leakage methods, the generation of concepts of new methods of achieving the desired zero leakage criteria and the development of detailed analysis and design of a selected concept. Other techniques of leak detection were explored with a view toward improving this area.

  19. Emerging Definition of Next-Generation of Aeronautical Communications

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.

    2006-01-01

    Aviation continues to experience rapid growth. In regions such as the United States and Europe air traffic congestion is constraining operations, leading to major new efforts to develop methodologies and infrastructures to enable continued aviation growth through transformational air traffic management systems. Such a transformation requires better communications linking airborne and ground-based elements. Technologies for next-generation communications, the required capacities, frequency spectrum of operation, network interconnectivity, and global interoperability are now receiving increased attention. A number of major planning and development efforts have taken place or are in process now to define the transformed airspace of the future. These activities include government and industry led efforts in the United States and Europe, and by international organizations. This paper will review the features, approaches, and activities of several representative planning and development efforts, and identify the emerging global consensus on requirements of next generation aeronautical communications systems for air traffic control.

  20. Aeronautical Mobile Airport Communications System (AeroMACS)

    NASA Technical Reports Server (NTRS)

    Budinger, James M.; Hall, Edward

    2011-01-01

    To help increase the capacity and efficiency of the nation s airports, a secure wideband wireless communications system is proposed for use on the airport surface. This paper provides an overview of the research and development process for the Aeronautical Mobile Airport Communications System (AeroMACS). AeroMACS is based on a specific commercial profile of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard known as Wireless Worldwide Interoperability for Microwave Access or WiMAX (WiMax Forum). The paper includes background on the need for global interoperability in air/ground data communications, describes potential AeroMACS applications, addresses allocated frequency spectrum constraints, summarizes the international standardization process, and provides findings and recommendations from the world s first AeroMACS prototype implemented in Cleveland, Ohio, USA.

  1. Improving stopping construction to minimize leakage

    PubMed Central

    Grau, Roy H.; Mazzella, Andrew L.; Martikainen, Anu L.

    2015-01-01

    The proper sealing of stoppings is an important step in reducing leakage from the intake to the return airways. Leakage and the subsequent loss of ventilation resulting from improperly sealed stoppings can lead to unhealthy and unsafe working conditions. The research presented in this paper investigates the total leakage of a stopping, including air leakage through the stopping, at the stopping perimeter, and through the coalbed. The study also examines sealing considerations for stoppings that are constructed under roof control screen, the effects that wooden wedges had on inhibiting efficient application of polyurethane foam sealant, and airflow leakage through the surrounding coal. The work involved building a stopping in a dead end room of the NIOSH Safety Research Coal Mine and then pressurising the room using compressed air. Stopping leakage was evaluated by measuring air pressure loss in the enclosed room due to the air leakage. Part of the research utilises a diluted soap solution that was applied to the stopping and the surrounding coal to detect air leakage signified by bubble formations. The results show that stopping leakage can be minimised with proper sealing PMID:26379366

  2. Leakage-current properties of encapsulants

    NASA Technical Reports Server (NTRS)

    Wen, L. C.

    1986-01-01

    A theoretical modeling of leakage current in ethylene vinyl acetate (EVA) and polyvinyl butyral (PVB) modules is being developed and is described. The modeling effort derives mathematical relationships for the bulk and surface conductivites of EVA and PVB, the surface conductivities of glass and polymeric films, and the EVA and PVB pottants, all as functions of environmental parameters. Results from the modeling indicate that for glass/EVA, the glass surface controls the interfacial conductivity, although EVA bulk conductivity controls total leakage current. For PVB/glass, the interface conductivity controls leakage currents for relative humidity (RH) less than 40 to 50%, but PVB bulk conductivity controls leakage current above 50% RH.

  3. Preoperative Nutritional Therapy Reduces the Risk of Anastomotic Leakage in Patients with Crohn's Disease Requiring Resections

    PubMed Central

    Guo, Zhen; Guo, Dong; Gong, Jianfeng; Zhu, Weiming; Zuo, Lugen; Sun, Jing; Li, Ning; Li, Jieshou

    2016-01-01

    Background. The rate of anastomotic leakage is high in surgeries for Crohn's disease, and therefore a temporary diverting stoma is often needed. We conducted this study to investigate whether preoperative nutritional therapy could reduce the risk of anastomotic leakage while decreasing the frequency of temporary stoma formation. Methods. This was a retrospective study. Patients requiring bowel resections due to Crohn's disease were reviewed. The rate of anastomotic leakage and temporary diverting stoma was compared between patients who received preoperative nutritional therapy and those on a normal diet before surgery. Possible predictive factors for anastomotic leakage were also analyzed. Results. One hundred and fourteen patients undergoing 123 surgeries were included. Patients in nutritional therapy (NT) group had a significantly lower level of C-reactive protein on the day before surgery. Patients in NT group suffered less anastomotic leakage (2.3% versus 17.9%, P = 0.023) and less temporary diverting stoma (22.8% versus 40.9%, P = 0.036). Serum albumin of the day before surgery ≤35 g/L and preoperative nutritional therapy were identified as factors which independently affected the rate of anastomotic leakage. Conclusion. Preoperative nutritional therapy reduced the risk of anastomotic leakage and the frequency of temporary diverting stoma formation in patients with Crohn's disease requiring resections. PMID:26858749

  4. Aeronautical Satellite Comunications at T1 Data Rates

    NASA Technical Reports Server (NTRS)

    Agan, M. J.; Densmore, A. C.

    1996-01-01

    The Advanced Communications Technology Satellite (ACTS) Broadband Aeronautical Terminal was developed by NASA's Jet Propulsion Laboratory together with various industry/government partners to investigate high data rate aeronautical applications of ACTS technologies.

  5. A CCIR aeronautical mobile satellite report

    NASA Astrophysics Data System (ADS)

    Davarian, Faramaz; Bishop, Dennis; Rogers, David; Smith, Ernest K.

    1989-08-01

    Propagation effects in the aeronautical mobile-satellite service differ from those in the fixed-satellite service and other mobile-satellite services because: small antennas are used on aircraft, and the aircraft body may affect the performance of the antenna; high aircraft speeds cause large Doppler spreads; aircraft terminals must accommodate a large dynamic range in transmission and reception; and due to their high speeds, banking maneuvers, and three-dimensional operation, aircraft routinely require exceptionally high integrity of communications, making even short-term propagation effects very important. Data and models specifically required to characterize the path impairments are discussed, which include: tropospheric effects, including gaseous attenuation, cloud and rain attenuation, fog attenuation, refraction and scintillation; surface reflection (multipath) effects; ionospheric effects such as scintillation; and environmental effects (aircraft motion, sea state, land surface type). Aeronautical mobile-satellite systems may operate on a worldwide basis, including propagation paths at low elevation angles. Several measurements of multipath parameters over land and sea were conducted. In some cases, laboratory simulations are used to compare measured data and verify model parameters. The received signals is considered in terms of its possible components: a direct wave subject to atmospheric effects, and a reflected wave, which generally contains mostly a diffuse component.

  6. National Advisory Committee for Aeronautics Meeting

    NASA Technical Reports Server (NTRS)

    1921-01-01

    The National Advisory Committee for Aeronautics in session at Washington to discuss plans to place America foremost in the development of avaition. A report was heard from Dr. Ames, chairman of the executive committee, on research work to develop the new heavy oil fuel injection aircraft engine which does away with carburetor and spark plugs, and will lesson the fire hazard. Dr. S.W. Stratton, secretary of the committee and director of the Bureau of Standards, is shown seated at the extreme left. Around the table, left to right, are: Prof. Charles F. Marvin, chief of the weather bureau; Dr. John F. Hayford (Northwestern Univ.); Orville Wright; Major Thurman H. Bane (chief Engineer Div. Army); Paul Henderson, (Second Ass. Postmaster Gen.); Rear Adm. W.A. Moffet, Chief Bureau Aeronautics, Navy; Dr. Michael I. Pupin, (Columbia Univ.); Rear Adm. D.W. Taylor, U.S.N. (Chief Bureau Construction and repair); Dr. Charles D. Walcott, chairman, (Chief Air Service) and Dr. Joesph S. Ames, chairman executive committee (John Hopkins Univ.)

  7. A CCIR aeronautical mobile satellite report

    NASA Technical Reports Server (NTRS)

    Davarian, Faramaz; Bishop, Dennis; Rogers, David; Smith, Ernest K.

    1989-01-01

    Propagation effects in the aeronautical mobile-satellite service differ from those in the fixed-satellite service and other mobile-satellite services because: small antennas are used on aircraft, and the aircraft body may affect the performance of the antenna; high aircraft speeds cause large Doppler spreads; aircraft terminals must accommodate a large dynamic range in transmission and reception; and due to their high speeds, banking maneuvers, and three-dimensional operation, aircraft routinely require exceptionally high integrity of communications, making even short-term propagation effects very important. Data and models specifically required to characterize the path impairments are discussed, which include: tropospheric effects, including gaseous attenuation, cloud and rain attenuation, fog attenuation, refraction and scintillation; surface reflection (multipath) effects; ionospheric effects such as scintillation; and environmental effects (aircraft motion, sea state, land surface type). Aeronautical mobile-satellite systems may operate on a worldwide basis, including propagation paths at low elevation angles. Several measurements of multipath parameters over land and sea were conducted. In some cases, laboratory simulations are used to compare measured data and verify model parameters. The received signals is considered in terms of its possible components: a direct wave subject to atmospheric effects, and a reflected wave, which generally contains mostly a diffuse component.

  8. Robust Timing Synchronization in Aeronautical Mobile Communication Systems

    NASA Technical Reports Server (NTRS)

    Xiong, Fu-Qin; Pinchak, Stanley

    2004-01-01

    This work details a study of robust synchronization schemes suitable for satellite to mobile aeronautical applications. A new scheme, the Modified Sliding Window Synchronizer (MSWS), is devised and compared with existing schemes, including the traditional Early-Late Gate Synchronizer (ELGS), the Gardner Zero-Crossing Detector (GZCD), and the Sliding Window Synchronizer (SWS). Performance of the synchronization schemes is evaluated by a set of metrics that indicate performance in digital communications systems. The metrics are convergence time, mean square phase error (or root mean-square phase error), lowest SNR for locking, initial frequency offset performance, midstream frequency offset performance, and system complexity. The performance of the synchronizers is evaluated by means of Matlab simulation models. A simulation platform is devised to model the satellite to mobile aeronautical channel, consisting of a Quadrature Phase Shift Keying modulator, an additive white Gaussian noise channel, and a demodulator front end. Simulation results show that the MSWS provides the most robust performance at the cost of system complexity. The GZCD provides a good tradeoff between robustness and system complexity for communication systems that require high symbol rates or low overall system costs. The ELGS has a high system complexity despite its average performance. Overall, the SWS, originally designed for multi-carrier systems, performs very poorly in single-carrier communications systems. Table 5.1 in Section 5 provides a ranking of each of the synchronization schemes in terms of the metrics set forth in Section 4.1. Details of comparison are given in Section 5. Based on the results presented in Table 5, it is safe to say that the most robust synchronization scheme examined in this work is the high-sample-rate Modified Sliding Window Synchronizer. A close second is its low-sample-rate cousin. The tradeoff between complexity and lowest mean-square phase error determines

  9. Distributed temperature monitoring for liquid sodium leakage detection using OFDR-based Rayleigh backscattering

    NASA Astrophysics Data System (ADS)

    Boldyreva, E.; Cotillard, R.; Laffont, G.; Ferdinand, P.; Cambet, D.; Jeannot, J.-P.; Charvet, P.; Albaladéjo, S.; Rodriguez, G.

    2014-05-01

    For the first time, a gold coated single mode optical fiber has been used to detect a liquid sodium leakage on a pipe of secondary circuit pipe mock-up of nuclear fast reactor (Gen IV) by means of Optical Frequency Domain Reflectometry-based on Rayleigh backscattering. During 150 min of the experiment we were able to detect and monitor the evolution of a liquid sodium leakage on the surface of the pipe.

  10. 78 FR 41114 - NASA Advisory Council; Aeronautics Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-09

    ... SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Meeting AGENCY: National Aeronautics... meeting of the Aeronautics Committee of the NASA Advisory Council. This Committee reports to the NAC. The.... to 5:00 p.m.; Local Time. ADDRESSES: NASA Headquarters, Room 6E40, 300 E Street SW., Washington,...

  11. 76 FR 58843 - NASA Advisory Council; Aeronautics Committee; Meeting

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    ... SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Meeting AGENCY: National Aeronautics... meeting of the Aeronautics Committee of the NASA Advisory Council. The meeting will be held for the...) 358-0566, or susan.l.minor@nasa.gov . SUPPLEMENTARY INFORMATION: The meeting will be open to...

  12. 75 FR 17166 - NASA Advisory Council; Aeronautics Committee; Meeting

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  13. 78 FR 10640 - NASA Advisory Council; Aeronautics Committee; Meeting

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    ... SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Meeting AGENCY: National Aeronautics... meeting of the Aeronautics Committee of the NASA Advisory Council. The meeting will be held for the... Administration Headquarters, Washington, DC 20546, (202) 358-0566, or susan.l.minor@nasa.gov ....

  14. NASA's Role in Aeronautics: A Workshop. Volume III - Transport Aircraft.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Assembly of Engineering.

    The central task of a 1980 workshop on the role of the National Aeronautics and Space Administration (NASA) in aeronautics was to examine the relationship of NASA's research capabilities to the state of U.S. aviation and to make recommendations about NASA's future role in aeronautics. The specific task of the Panel on Transport Aircraft was to…

  15. Aeronautics and Space Report of the President: 1975 Activities.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    This report, submitted to the Congress by President Ford in accordance with the National Aeronautics and Space Act of 1958, summarizes the United States' space and aeronautics activities for the year 1975. Detailed summaries of the activities of the following governmental departments or agencies are provided: National Aeronautics and Space…

  16. 78 FR 52230 - Government/Industry Aeronautical Charting Forum Meeting

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    2013-08-22

    ... Federal Aviation Administration Government/Industry Aeronautical Charting Forum Meeting AGENCY: Federal...-annual meeting of the Federal Aviation Administration (FAA) Aeronautical Charting Forum (ACF) to discuss...), notice is hereby given of a meeting of the FAA Aeronautical Charting Forum to be held from October...

  17. 76 FR 53530 - Government/Industry Aeronautical Charting Forum Meeting

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    2011-08-26

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  18. 76 FR 12211 - Government/Industry Aeronautical Charting Forum Meeting

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    2011-03-04

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  19. 75 FR 11225 - Government/Industry Aeronautical Charting Forum Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-10

    ... Federal Aviation Administration Government/Industry Aeronautical Charting Forum Meeting AGENCY: Federal... Forum (ACF 10-01) to discuss informational content and design of aeronautical charts and related.... App. II), notice is hereby given of a meeting of the FAA Aeronautical Charting Forum to be held...

  20. 77 FR 50759 - Government/Industry Aeronautical Charting Forum Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-22

    ... TRANSPORTATION Federal Aviation Administration Government/Industry Aeronautical Charting Forum Meeting AGENCY... announces the bi-annual meeting of the Federal Aviation Administration (FAA) Aeronautical Charting Forum... hereby given of a meeting of the FAA Aeronautical Charting Forum to be held from October 23...

  1. 78 FR 12415 - Government/Industry Aeronautical Charting Forum Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-22

    ... Federal Aviation Administration Government/Industry Aeronautical Charting Forum Meeting AGENCY: Federal...-annual meeting of the Federal Aviation Administration (FAA) Aeronautical Charting Forum (ACF) to discuss...), notice is hereby given of a meeting of the FAA Aeronautical Charting Forum to be held from April...

  2. 75 FR 54221 - Government/Industry Aeronautical Charting Forum Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-03

    ... Federal Aviation Administration Government/Industry Aeronautical Charting Forum Meeting AGENCY: Federal...-annual meeting of the Federal Aviation Administration (FAA) Aeronautical Charting Forum (ACF) to discuss... is hereby given of a meeting of the FAA Aeronautical Charting Forum to be held from October...

  3. NASA's Role in Aeronautics: A Workshop. Volume II - Military Aviation.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Assembly of Engineering.

    The central task of a 1980 workshop on the role of the National Aeronautics and Space Administration (NASA) in aeronautics was to examine the relationship of NASA's research capabilities to the state of U.S. aviation and to make recommendations about NASA's future role in aeronautics. The findings and recommendations of the Panel on Military…

  4. 14 CFR 61.159 - Aeronautical experience: Airplane category rating.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aeronautical experience: Airplane category... Transport Pilots § 61.159 Aeronautical experience: Airplane category rating. (a) Except as provided in... certificate with an airplane category and class rating must have at least 1,500 hours of total time as a...

  5. 76 FR 183 - NASA Advisory Council; Aeronautics Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-03

    ... SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Meeting AGENCY: National Aeronautics... meeting of the Aeronautics Committee of the NASA Advisory Council. The meeting will be held for the... Administration Headquarters, Washington, DC 20546, (202) 358-0566, or susan.l.minor@nasa.gov ....

  6. NASA's Role in Aeronautics: A Workshop. Volume IV - General Aviation.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Assembly of Engineering.

    The central task of a 1980 workshop on the role of the National Aeronautics and Space Administration (NASA) in aeronautics was to examine the relationship of NASA's research capabilities to the state of U.S. aviation and to make recommendations about NASA's future role in aeronautics. The findings and recommendations of the Panel on General…

  7. 16 CFR 1507.5 - Pyrotechnic leakage.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Pyrotechnic leakage. 1507.5 Section 1507.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS FIREWORKS DEVICES § 1507.5 Pyrotechnic leakage. The pyrotechnic chamber in fireworks devices shall be...

  8. 16 CFR 1507.5 - Pyrotechnic leakage.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Pyrotechnic leakage. 1507.5 Section 1507.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS FIREWORKS DEVICES § 1507.5 Pyrotechnic leakage. The pyrotechnic chamber in fireworks devices shall be...

  9. 16 CFR 1507.5 - Pyrotechnic leakage.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Pyrotechnic leakage. 1507.5 Section 1507.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS FIREWORKS DEVICES § 1507.5 Pyrotechnic leakage. The pyrotechnic chamber in fireworks devices shall be...

  10. 16 CFR 1507.5 - Pyrotechnic leakage.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Pyrotechnic leakage. 1507.5 Section 1507.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS FIREWORKS DEVICES § 1507.5 Pyrotechnic leakage. The pyrotechnic chamber in fireworks devices shall be...

  11. 16 CFR 1507.5 - Pyrotechnic leakage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Pyrotechnic leakage. 1507.5 Section 1507.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS FIREWORKS DEVICES § 1507.5 Pyrotechnic leakage. The pyrotechnic chamber in fireworks devices shall be...

  12. 49 CFR 236.735 - Current, leakage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Current, leakage. 236.735 Section 236.735 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Current, leakage. A stray electric current of relatively small value which flows through or across...

  13. 49 CFR 236.735 - Current, leakage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Current, leakage. 236.735 Section 236.735 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Current, leakage. A stray electric current of relatively small value which flows through or across...

  14. 49 CFR 236.735 - Current, leakage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Current, leakage. 236.735 Section 236.735 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Current, leakage. A stray electric current of relatively small value which flows through or across...

  15. 49 CFR 236.735 - Current, leakage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Current, leakage. 236.735 Section 236.735 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Current, leakage. A stray electric current of relatively small value which flows through or across...

  16. 49 CFR 236.735 - Current, leakage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Current, leakage. 236.735 Section 236.735 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Current, leakage. A stray electric current of relatively small value which flows through or across...

  17. Predicting Envelope Leakage in Attached Dwellings

    SciTech Connect

    Faakye, O.; Arena, L.; Griffiths, D.

    2013-07-01

    The most common method for measuring air leakage is to use a single blower door to pressurize and/or depressurize the test unit. In detached housing, the test unit is the entire home and the single blower door measures air leakage to the outside. In attached housing, this 'single unit', 'total', or 'solo' test method measures both the air leakage between adjacent units through common surfaces as well air leakage to the outside. Measuring and minimizing this total leakage is recommended to avoid indoor air quality issues between units, reduce energy losses to the outside, reduce pressure differentials between units, and control stack effect. However, two significant limitations of the total leakage measurement in attached housing are: for retrofit work, if total leakage is assumed to be all to the outside, the energy benefits of air sealing can be significantly over predicted; for new construction, the total leakage values may result in failing to meet an energy-based house tightness program criterion. The scope of this research is to investigate an approach for developing a viable simplified algorithm that can be used by contractors to assess energy efficiency program qualification and/or compliance based upon solo test results.

  18. Bag Test Measures Leakage From Insulated Pipe

    NASA Technical Reports Server (NTRS)

    Schock, Kent D.; Easter, Barry P.

    1994-01-01

    Test quantifies leakage of gas from pipe even though pipe covered with insulation. Involves use of helium analyzer to measure concentration of helium in impermeable bag around pipe. Test administered after standard soap-solution bubble test indicates presence and general class of leakage.

  19. 49 CFR 230.78 - Leakage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Brake and Signal Equipment § 230.78 Leakage. (a) Main reservoirs and related piping. Leakage from main reservoir and related piping shall be tested at every 92 service day inspection and shall not exceed an...

  20. 49 CFR 230.78 - Leakage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Brake and Signal Equipment § 230.78 Leakage. (a) Main reservoirs and related piping. Leakage from main reservoir and related piping shall be tested at every 92 service day inspection and shall not exceed an...

  1. New ac microammeter for leakage current measurement of biomedical equipment

    NASA Astrophysics Data System (ADS)

    Branca, F. P.; Del Prete, Z.; Marinozzi, F.

    1993-11-01

    A new inexpensive current probe for on-line leakage current measurement of biomedical devices in hospital environment is described. The prototype is designed to detect and measure leakage currents on the ground wire of the device's power cord so that its integrity can be monitored in real time. Realized with a sensing coil specially matched to a low-noise op amp, this probe adds only negligible impedance on the monitored ground lines. From this preliminary study about the device's metrological performances, a sensitivity of 10 nArms for a current range 1-500 μArms has emerged, together with a mean linearity error of 0.03% and a frequency response flat within 1% of gain from 50 to 2000 Hz.

  2. Application of Mobile-ip to Space and Aeronautical Networks

    NASA Technical Reports Server (NTRS)

    Leung, Kent; Shell, Dan; Ivancic, William D.; Stewart, David H.; Bell, Terry L.; Kachmar, Brian A.

    2001-01-01

    The National Aeronautics and Space Administration (NASA) is interested in applying mobile Internet protocol (mobile-ip) technologies to its space and aeronautics programs. In particular, mobile-ip will play a major role in the Advanced Aeronautic Transportation Technology (AAT-F), the Weather Information Communication (WINCOMM), and the Small Aircraft Transportation System (SATS) aeronautics programs. This paper describes mobile-ip and mobile routers--in particular, the features, capabilities, and initial performance of the mobile router are presented. The application of mobile-router technology to NASA's space and aeronautics programs is also discussed.

  3. Future developments in aeronautical satellite communications

    NASA Technical Reports Server (NTRS)

    Wood, Peter

    1990-01-01

    Very shortly aeronautical satellite communications will be introduced on a world wide basis. By the end of the year, voice communications (both to the cabin and cockpit) and packet data communications will be available to both airlines and executive aircraft. During the decade following the introduction of the system, there will be many enhancements and developments which will increase the range of applications, expand the potential number of users, and reduce costs. A number of ways in which the system is expected to evolve over this period are presented. Among the issues which are covered are the impact of spot beam satellites, spectrum and power conservation techniques, and the expanding range of user services.

  4. Adaptive multisatellite systems for aeronautical services.

    NASA Technical Reports Server (NTRS)

    Bisaga, J. J.; Redisch, W. N.

    1971-01-01

    The use of satellite systems to provide operational communications and ATC services to aircraft flying the oceanic routes has been the subject of considerable interest recently. Since most of the link factors are functions of geometry and the aircraft traffic density varies with time, the satellite power needed to meet the communication demand varies considerably in an oceanic area as a function of both location and time. An adaptive system that tailors the use of system resources to the needs of the user can result in an additional system capacity improvement by a factor of between two and three. Results of studies conducted to date indicate that simple implementation of adaptive techniques in aeronautical satellite systems is feasible. Study is continuing in this area and on the application of satellite multibeam techniques to gain even further increase in capacity.

  5. Performance of a Regional Aeronautical Telecommunications Network

    NASA Technical Reports Server (NTRS)

    Bretmersky, Steven C.; Ripamonti, Claudio; Konangi, Vijay K.; Kerczewski, Robert J.

    2001-01-01

    This paper reports the findings of the simulation of the ATN (Aeronautical Telecommunications Network) for three typical average-sized U.S. airports and their associated air traffic patterns. The models of the protocols were designed to achieve the same functionality and meet the ATN specifications. The focus of this project is on the subnetwork and routing aspects of the simulation. To maintain continuous communication between the aircrafts and the ground facilities, a model based on mobile IP is used. The results indicate that continuous communication is indeed possible. The network can support two applications of significance in the immediate future FTP and HTTP traffic. Results from this simulation prove the feasibility of development of the ATN concept for AC/ATM (Advanced Communications for Air Traffic Management).

  6. A fuel level sensor for aeronautical applications

    NASA Astrophysics Data System (ADS)

    Petrazzuoli, L.; Persichetti, G.; Onorato, G.; Grimaldi, I. A.; Testa, G.; Bernini, R.

    2015-03-01

    A novel fuel level sensor for aeronautical applications is developed. The sensor is based on an array of total internal reflection (TIR) point sensors. Respect to conventional TIR sensors the new design permits to be sensitive to common jet fuels (JetA, JP4,JP7) but also to operate with new alternative fuels. The sensor doesn't require aircraft calibration, temperature compensation and furthermore is able to operate correctly when partially or totally exposed to presence of condensed water on its surface. The point sensors are multiplexed on a single fiber by optical couplers and interrogated simultaneously by Optical Time Domain Reflectometry (OTDR) at a wavelength of 1550nm. Experimental results show a resolution of +/-1.5mm could be achieved. The sensors is also able to measure the free water level in the fuel.

  7. Health monitoring of aeronautical structures based on vibrations measurements

    NASA Astrophysics Data System (ADS)

    Bovio, Igor; Lecce, Leonardo

    2006-03-01

    Purpose of the paper is to present an innovative application inside the Non Destructive Testing field based on vibrations measurements, developed by the authors during the last three years, and already tested for analysing damage of many structural elements. The proposed new method is based on the acquisition and comparison of Frequency Response Functions (FRFs) of the monitored structure before and after an occurred damage. Structural damage modify the dynamical behaviour of the structure such as mass, stiffened and damping, and consequently the FRFs of the damaged structure in comparison with the FRFs of the sound structure, making possible to identify, to localize and quantify a structural damage. The activities, presented in the paper, mostly focused on a new FRFs processing technique based on the determining of a representative "Damage Index" for identifying and analysing damage both on real scale aeronautical structural components, like large-scale fuselage reinforced panels, and on aeronautical composite panels. Besides it has been carried out a dedicated neural network algorithm aiming at obtaining a "recognition-based learning"; this kind of learning methodology permits to train the neural network in order to let it recognises only "positive" examples discarding as a consequence the "negative" ones. Within the structural NDT a "positive" example means "healthy" state of the analysed structural component and, obviously, a "negative" one means a "damaged" or perturbed state. From an architectural point of view piezoceramic patches have been tested as actuators and sensors. Besides it has been used a laser-scanning vibrometer system to validate the behaviour of the piezoceramic patches.

  8. Air leakage of newly instaled residential windows

    SciTech Connect

    Weidt, J.; Weidt, J.

    1980-06-01

    The air-leakage characteristics of five major window designs were measured in a field survey conducted in Twin Cities, Minnesota. A total of 192 windows (16 manufacturers) were tested at 58 sites representing a cross-section of single-family homes, townhouses, low- and high-rise apartments, and condominiums. Air-leakage measurements of the installed windows were compared with the current standard used by industry and government of 0.50 ft/sup 3//min/linear ft of crack. Other parameters studied were: effect of sash and frame material, effect of leakage between window frame and wall, differences among the product lines of a single manufacturer and between manufacturers, effect of installation practices, effect of cold weather on performance, change in performance over time for older windows, and performance of fixed glazing. Based on industry and government standards, 40% of all windows tested showed air-leakage characteristics higher than the 0.50 cfm/lfc standard, and 60% exceeded manufacturers' specifications for performance which in some cases were lower than the general industry standard. Analysis of the impact of various parameters on air-leakage performance showed that the operational design of the window was the most critical determinant although the ranking changes if performance is expressed in cfm/unit area or cfm/opening area. Air leakage was measured using a portable pressurization chamber. Smoke pencils, thermographic techniques and extensive photographic documentation provided additional data as to the location and cause of air leakage problems.

  9. The revolutionary impact of evolving aeronautical technologies

    NASA Technical Reports Server (NTRS)

    Kayten, G. G.; Driver, C.; Maglieri, D. J.

    1984-01-01

    Recent advances in aeronautical technologies which could produce revolutionary changes in transport aircraft if fully implemented are delineated. Laminar flow control offers a L/D improvement from the current 18 to 22 if used with a 767 configuration. Higher aspect and thickness/chord ratios could yield more efficient structural designs and further drag reduction. High-strength, fiber-reinforced composite structures can reduce structural weight by 10-30 percent. Improved engine cooling methods, higher stage loadings and exhaust temperatures can lower the SFC by 15 percent, engine weight by 15 percent, and the parts count by 50 percent. Aft-mounted counterrotating propellers can potentially decrease the SFC an additional 15-20 percent. Supersonic transport aircraft with L/D ratios of 18 and 70 seat miles/gal fuel efficiency can now be built that weigh half as much as the Concorde and carry the same load. The new SST would have superplastic-molded Al alloy structures.

  10. Life prediction technologies for aeronautical propulsion systems

    NASA Technical Reports Server (NTRS)

    Mcgaw, Michael A.

    1990-01-01

    Fatigue and fracture problems continue to occur in aeronautical gas turbine engines. Components whose useful life is limited by these failure modes include turbine hot-section blades, vanes, and disks. Safety considerations dictate that catastrophic failures be avoided, while economic considerations dictate that catastrophic failures be avoided, while economic considerations dictate that noncatastrophic failures occur as infrequently as possible. Therefore, the decision in design is making the tradeoff between engine performance and durability. LeRC has contributed to the aeropropulsion industry in the area of life prediction technology for over 30 years, developing creep and fatigue life prediction methodologies for hot-section materials. At the present time, emphasis is being placed on the development of methods capable of handling both thermal and mechanical fatigue under severe environments. Recent accomplishments include the development of more accurate creep-fatigue life prediction methods such as the total strain version of LeRC's strain-range partitioning (SRP) and the HOST-developed cyclic damage accumulation (CDA) model. Other examples include the development of a more accurate cumulative fatigue damage rule - the double damage curve approach (DDCA), which provides greatly improved accuracy in comparison with usual cumulative fatigue design rules. Other accomplishments in the area of high-temperature fatigue crack growth may also be mentioned. Finally, we are looking to the future and are beginning to do research on the advanced methods which will be required for development of advanced materials and propulsion systems over the next 10-20 years.

  11. Leakage current and commutation losses reduction in electric drives for Hybrid Electric Vehicle

    NASA Astrophysics Data System (ADS)

    Miliani, El Hadj

    2014-06-01

    Nowadays, leakage current and inverter losses, produced by adjustable-speed AC drive systems become one of the main interested subject for researchers on Electric Vehicle (EV) and Hybrid Electric Vehicle (HEV) technology. The continuous advancements in solid state device engineering have considerably minimized the switching transients for power switches but the high dv/dt and high switching frequency have caused many adverse effects such as shaft voltage, bearing current, leakage current and electromagnetic interference (EMI). The major objective of this paper is to investigate and suppress of the adverse effects of a PWM inverter feeding AC motor in EV and HEV. A technique to simultaneously reduce the leakage current and the switching losses is presented in this paper. Based on a discontinuous space vector pulse width modulation (DSVPWM) and a modular switches gate resistance, inverter losses and leakage current are reduced. Algorithms are presented and implemented on a DSP controller and experimental results are presented.

  12. Power Beaming Leakage Radiation as a SETI Observable

    NASA Astrophysics Data System (ADS)

    Benford, James N.; Benford, Dominic J.

    2016-07-01

    The most observable leakage radiation from an advanced civilization may well be from the use of power beaming to transfer energy and accelerate spacecraft. Applications suggested for power beaming involve launching spacecraft to orbit, raising satellites to a higher orbit, and interplanetary concepts involving space-to-space transfers of cargo or passengers. We also quantify beam-driven launch to the outer solar system, interstellar precursors, and ultimately starships. We estimate the principal observable parameters of power beaming leakage. Extraterrestrial civilizations would know their power beams could be observed, and so could put a message on the power beam and broadcast it for our receipt at little additional energy or cost. By observing leakage from power beams we may find a message embedded on the beam. Recent observations of the anomalous star KIC 8462852 by the Allen Telescope Array (ATA) set some limits on extraterrestrial power beaming in that system. We show that most power beaming applications commensurate with those suggested for our solar system would be detectable if using the frequency range monitored by the ATA, and so the lack of detection is a meaningful, if modest, constraint on extraterrestrial power beaming in that system. Until more extensive observations are made, the limited observation time and frequency coverage are not sufficiently broad in frequency and duration to produce firm conclusions. Such beams would be visible over large interstellar distances. This implies a new approach to the SETI search: instead of focusing on narrowband beacon transmissions generated by another civilization, look for more powerful beams with much wider bandwidth. This requires a new approach for their discovery by telescopes on Earth. Further studies of power beaming applications should be performed, potentially broadening the parameter space of the observable features that we have discussed here.

  13. A cumulative index to a continuing bibliography on aeronautical engineering

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This bibliography is a cumulative index to the abstracts contained in NASA-SP-7037(184) through NASA-SP-7037(195) of Aeronautical Engineering: A Continuing Bibliography. NASA SP-7037 and its supplements have been compiled through the cooperative efforts of the American Institute of Aeronautics and Astronautics (AIAA) and the National Aeronautics and Space Administration (NASA). This cumulative index includes subject, personal author, corporate source, foreign technology, contract, report number, and accession number indexes.

  14. Aeronautical engineering: A cumulative index to a continuing bibliography

    NASA Technical Reports Server (NTRS)

    1988-01-01

    This bibliography is a cumulative index to the abstracts contained in NASA SP-7037(210) through NASA SP-7037(221) of Aeronautical Engineering: A Continuing Bibliography. NASA SP-7037 and its supplements have been compiled through the cooperative efforts of the American Institute of Aeronautics and Astronautics (AIAA) and the National Aeronautics and Space Administration (NASA). This cumulative index includes subject, personal author, corporate source, foreign technology, contract number, report number, and accession number indexes.

  15. Aeronautical Engineering: A continuing bibliography, 1982 cumulative index

    NASA Technical Reports Server (NTRS)

    1983-01-01

    This bibliography is a cumulative index to the abstracts contained in NASA SP-7037 (145) through NASA SP-7037 (156) of Aeronautical Engineering: A Continuing Bibliography. NASA SP-7037 and its supplements have been compiled through the cooperative efforts of the American Institute of Aeronautics and Astronautics (AIAA) and the National Aeronautics and Space Administration (NASA). This cumulative index includes subject, personal author, corporate source, contract, and report number indexes.

  16. Cyber Technology for Materials and Structures in Aeronautics and Aerospace

    NASA Technical Reports Server (NTRS)

    Pipes, R. Byron

    2002-01-01

    The evolution of composites applications in aeronautics from 1970 to the present is discussed. The barriers and challenges to economic application and to certification are presented and recommendations for accelerated development are outlined. The potential benefits of emerging technologies to aeronautics and their foundation in composite materials are described and the resulting benefits in vehicle take off gross weight are quantified. Finally, a 21st century vision for aeronautics in which human mobility is increased by an order of magnitude is articulated.

  17. A cumulative index to Aeronautical Engineering: A continuing bibliography

    NASA Technical Reports Server (NTRS)

    1982-01-01

    This bibliography is a cumulated index to the abstracts contained in NASA SP-7037(132) through NASA SP-7037(143) of Aeronautical Engineering: A continuing bibliography. NASA SP-7037 and its supplements have been compiled through the cooperative efforts of the American Institute of Aeronautics and Astronautics (AIAA) and the National Aeronautics and Space Administration (NASA). This cumulative index includes subject, personal author, corporate source, contract, and report number indexes.

  18. Aeronautical engineering: A cumulative index to a continuing bibliography

    NASA Technical Reports Server (NTRS)

    1987-01-01

    This bibliography is a cumulative index to the abstracts contained in NASA SP-7037 (197) through NASA SP-7037 (208) of Aeronautical Engineering: A Continuing Bibliography. NASA SP-7037 and its supplements have been compiled through the cooperative efforts of the American Institute of Aeronautics and Astronautics (AIAA) and the National Aeronautics and Space Administration (NASA). This cumulative index includes subject, personal author, corporate source, foreign technology, contract, report number, and accession number indexes.

  19. Early Alzheimer's Linked to Brain 'Leakage'

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_159116.html Early Alzheimer's Linked to Brain 'Leakage' Normally, blood-brain barrier ... HealthDay News) -- People in the early stages of Alzheimer's disease may have more "leaks" in the barrier ...

  20. Composite seal reduces alkaline battery leakage

    NASA Technical Reports Server (NTRS)

    Clatterbuck, C. H.; Plitt, K. F.

    1965-01-01

    Composite seal consisting of rubber or plastic washers and a metal washer reduces alkaline battery leakage. Adhesive is applied to each washer interface, and the washers are held together mechanically.

  1. Early Alzheimer's Linked to Brain 'Leakage'

    MedlinePlus

    ... news/fullstory_159116.html Early Alzheimer's Linked to Brain 'Leakage' Normally, blood-brain barrier prevents this from happening To use the ... more "leaks" in the barrier that separates the brain from the bloodstream, a small study suggests. Known ...

  2. Apparatus for detecting leakage of liquid sodium

    DOEpatents

    Himeno, Yoshiaki

    1978-01-01

    An apparatus for detecting the leakage of liquid sodium includes a cable-like sensor adapted to be secured to a wall of piping or other equipment having sodium on the opposite side of the wall, and the sensor includes a core wire electrically connected to the wall through a leak current detector and a power source. An accidental leakage of the liquid sodium causes the corrosion of a metallic layer and an insulative layer of the sensor by products resulted from a reaction of sodium with water or oxygen in the atmospheric air so as to decrease the resistance between the core wire and the wall. Thus, the leakage is detected as an increase in the leaking electrical current. The apparatus is especially adapted for use in detecting the leakage of liquid sodium from sodium-conveying pipes or equipment in a fast breeder reactor.

  3. Measuring Heat-Exchanger Water Leakage

    NASA Technical Reports Server (NTRS)

    Zampiceni, J.

    1986-01-01

    Water leakage in heat exchanger measured directly with help of electroytic hygrometer. In new technique, flow of nitrogen gas set up in one loop of heat exchanger. Other loop filled with water under pressure. Water concentration produced by leakage of water into nitrogen flow measured by hygrometer. New measurement method determines water concentrations up to 2,000 parts per million with accuracy of +/- 5 percent.

  4. Technology evaluation for space station atmospheric leakage

    SciTech Connect

    Lemon, D.K.; Friesel, M.A.; Griffin, J.W.; Skorpik, J.R.; Shepard, C.L.; Antoniak, Z.I.; Kurtz, R.J.

    1990-02-01

    A concern in operation of a space station is leakage of atmosphere through seal points and through the walls as a result of damage from particle (space debris and micrometeoroid) impacts. This report describes a concept for a monitoring system to detect atmosphere leakage and locate the leak point. The concept is based on analysis and testing of two basic methods selected from an initial technology survey of potential approaches. 18 refs., 58 figs., 5 tabs.

  5. Aeronautics and Space Report of the President

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Fiscal Year (FY) 2002 brought advances on many fronts in support of NASA's new vision, announced by Administrator Sean O Keefe on April 12, "to improve life here, to extend life to there, to find life beyond." NASA successfully carried out four Space Shuttle missions, including three to the International Space Station (ISS) and one servicing mission to the Hubble Space Telescope (HST). By the end of the fiscal year, humans had occupied the ISS continuously for 2 years. NASA also managed five expendable launch vehicle (ELV) missions and participated in eight international cooperative ELV launches. In the area of space science, two of the Great Observatories, the Hubble Space Telescope and the Chandra X-Ray Observatory, continued to make spectacular observations. The Mars Global Surveyor and Mars Odyssey carried out their mapping missions of the red planet in unprecedented detail. Among other achievements, the Near Earth Asteroid Rendezvous (NEAR) Shoemaker spacecraft made the first soft landing on an asteroid, and the Solar and Heliospheric Observatory (SOHO) monitored a variety of solar activity, including the largest sunspot observed in 10 years. The education and public outreach program stemming from NASA's space science missions continues to grow. In the area of Earth science, attention focused on completing the first Earth Observing Satellite series. Four spacecraft were successfully launched. The goal is to understand our home planet as a system, as well as how the global environment responds to change. In aerospace technology, NASA conducted studies to improve aviation safety and environmental friendliness, progressed with its Space Launch Initiative Program, and explored a variety of pioneering technologies, including nanotechnology, for their application to aeronautics and aerospace. NASA remained broadly engaged in the international arena and concluded over 60 international cooperative and reimbursable international agreements during FY 2002.

  6. Leakage Suppression in the Toric Code

    NASA Astrophysics Data System (ADS)

    Suchara, Martin; Cross, Andrew; Gambetta, Jay

    2015-03-01

    Quantum codes excel at correcting local noise but fail to correct leakage faults that excite qubits to states outside the computational space. Aliferis and Terhal have shown that an accuracy threshold exists for leakage faults using gadgets called leakage reduction units (LRUs). However, these gadgets reduce the threshold and increase experimental complexity, and the costs have not been thoroughly understood. We explore a variety of techniques for leakage resilience in topological codes. Our contributions are threefold. First, we develop a leakage model that differs in critical details from earlier models. Second, we use Monte-Carlo simulations to survey several syndrome extraction circuits. Third, given the capability to perform 3-outcome measurements, we present a dramatically improved syndrome processing algorithm. Our simulations show that simple circuits with one extra CNOT per qubit reduce the accuracy threshold by less than a factor of 4 when leakage and depolarizing noise rates are comparable. This becomes a factor of 2 when the decoder uses 3-outcome measurements. Finally, when the physical error rate is less than 2 ×10-4 , placing LRUs after every gate may achieve the lowest logical error rate. We expect that the ideas may generalize to other topological codes.

  7. Advancing Aeronautics: A Decision Framework for Selecting Research Agendas

    NASA Technical Reports Server (NTRS)

    Anton, Philip S.; Ecola, Liisa; Kallimani, James G.; Light, Thomas; Ohlandt, Chad J. R.; Osburg, Jan; Raman, Raj; Grammich, Clifford A.

    2011-01-01

    Publicly funded research has long played a role in the development of aeronautics, ranging from foundational research on airfoils to development of the air-traffic control system. Yet more than a century after the research and development of successful controlled, sustained, heavier-than-air flight vehicles, there are questions over the future of aeronautics research. The field of aeronautics is relatively mature, technological developments within it have become more evolutionary, and funding decisions are sometimes motivated by the continued pursuit of these evolutionary research tracks rather than by larger factors. These developments raise questions over whether public funding of aeronautics research continues to be appropriate or necessary and at what levels. Tightened federal budgets and increasing calls to address other public demands make these questions sharper still. To help it address the questions of appropriate directions for publicly funded aeronautics research, the National Aeronautics and Space Administration's (NASA's) Aeronautics Research Mission Directorate (ARMD) asked the RAND Corporation to assess the elements required to develop a strategic view of aeronautics research opportunities; identify candidate aeronautic grand challenges, paradigms, and concepts; outline a framework for evaluating them; and exercise the framework as an example of how to use it. Accordingly, this research seeks to address these questions: What aeronautics research should be supported by the U.S. government? What compelling and desirable benefits drive government-supported research? How should the government--especially NASA--make decisions about which research to support? Advancing aeronautics involves broad policy and decisionmaking challenges. Decisions involve tradeoffs among competing perspectives, uncertainties, and informed judgment.

  8. NASA aeronautics. [fact sheet on NASA programs for aeronautical research and aircraft development

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A fact sheet depicting the NASA programs involving aircraft development and aeronautics is presented. The fact sheet consists of artist concepts of the various aircraft which represent specific programs. Among the subjects discussed in the concise explanatory notes are: (1) the YF-12 aircraft, (2) hypersonic drag tests in wind tunnels, (3) augmentor wing concepts, (4) rotary wing development, (5) fly-by-wire aircraft control, (6) supercritical wings, (7) the quiet engine program for noise and emission abatement, (8) flight capabilities of lifting bodies, (9) tilt rotor concepts for improved helicopter performance, and (10) flight safety improvements for general aviation aircraft.

  9. 47 CFR 87.375 - Frequencies.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Frequencies. 87.375 Section 87.375... Aeronautical Search and Rescue Stations § 87.375 Frequencies. (a) The frequency 123.100 MHz is available for... rescue station must be equipped to operate on this frequency. (b) The frequency 122.900 MHz is...

  10. 47 CFR 87.375 - Frequencies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Frequencies. 87.375 Section 87.375... Aeronautical Search and Rescue Stations § 87.375 Frequencies. (a) The frequency 123.100 MHz is available for... rescue station must be equipped to operate on this frequency. (b) The frequency 122.900 MHz is...

  11. 47 CFR 87.375 - Frequencies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 87.375 Section 87.375... Aeronautical Search and Rescue Stations § 87.375 Frequencies. (a) The frequency 123.100 MHz is available for... rescue station must be equipped to operate on this frequency. (b) The frequency 122.900 MHz is...

  12. 47 CFR 87.375 - Frequencies.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Frequencies. 87.375 Section 87.375... Aeronautical Search and Rescue Stations § 87.375 Frequencies. (a) The frequency 123.100 MHz is available for... rescue station must be equipped to operate on this frequency. (b) The frequency 122.900 MHz is...

  13. 47 CFR 87.375 - Frequencies.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequencies. 87.375 Section 87.375... Aeronautical Search and Rescue Stations § 87.375 Frequencies. (a) The frequency 123.100 MHz is available for... rescue station must be equipped to operate on this frequency. (b) The frequency 122.900 MHz is...

  14. Identification of Technologies for Provision of Future Aeronautical Communications

    NASA Technical Reports Server (NTRS)

    Gilbert, Tricia; Dyer, Glen; Henriksen, Steve; Berger, Jason; Jin, Jenny; Boci, Tony

    2006-01-01

    This report describes the process, findings, and recommendations of the second of three phases of the Future Communications Study (FCS) technology investigation conducted by NASA Glenn Research Center and ITT Advanced Engineering & Sciences Division for the Federal Aviation Administration (FAA). The FCS is a collaborative research effort between the FAA and Eurocontrol to address frequency congestion and spectrum depletion for safety critical airground communications. The goal of the technology investigation is to identify technologies that can support the longterm aeronautical mobile communication operating concept. A derived set of evaluation criteria traceable to the operating concept document is presented. An adaptation of the analytical hierarchy process is described and recommended for selecting candidates for detailed evaluation. Evaluations of a subset of technologies brought forward from the prescreening process are provided. Five of those are identified as candidates with the highest potential for continental airspace solutions in L-band (P-34, W-CDMA, LDL, B-VHF, and E-TDMA). Additional technologies are identified as best performers in the unique environments of remote/oceanic airspace in the satellite bands (Inmarsat SBB and a custom satellite solution) and the airport flight domain in C-band (802.16e). Details of the evaluation criteria, channel models, and the technology evaluations are provided in appendixes.

  15. REVIEW ARTICLE: Recent developments in smart structures with aeronautical applications

    NASA Astrophysics Data System (ADS)

    Loewy, Robert G.

    1997-10-01

    The original version of this paper was presented and distributed as part of the 37th Israel Annual Conference on Aerospace Sciences Proceedings. Without attempting a thorough review of the burgeoning literature, the results of a representative sampling of recent papers dealing with smart materials and structures as actuators in aeronautical systems are summarized here. Their potential for improving performance, handling qualities in a stall, and increasing fatigue life is discussed briefly as requiring relatively slow-acting shape and shape-distribution changes. A similar review is made of applications for improving aeroelastic divergence, flutter instabilities, and tail buffeting on fixed-wing aircraft; and reducing vibrations, improving external acoustics, and providing flight controls for rotating-wing aircraft - all of which require a high-frequency response. The status of some of the most promising developments is noted and the remaining problems are touched on. Two approaches, which have not been given substantial attention elsewhere, are reviewed; these are: developing concentrated, namely nondistributed, piezoelectric actuators in helicoidal configurations, on the one hand, as a way to improve force - deflection output; and using control surfaces purposefully designed to be marginally unstable and stabilized by smart structures, on the other hand, as a means of reducing the force - deflection combinations required of smart-structure actuators.

  16. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 405

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This report lists reports, articles and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles.

  17. Aeronautical engineering: A continuing bibliography with indexes (supplement 313)

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This bibliography lists 179 reports, articles, and other documents introduced into the NASA scientific and technical information system in Jan. 1995. Subject coverage includes: engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles.

  18. Aeronautical engineering: A continuing bibliography with indexes (supplement 284)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This bibliography lists 974 reports, articles, and other documents introduced into the NASA scientific and technical information system in Oct. 1992. The coverage includes documents on design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles.

  19. The Western Aeronautical Test Range of NASA Ames Research Center

    NASA Technical Reports Server (NTRS)

    Moore, A. L.

    1984-01-01

    An overview of the Western Aeronautical Test Range (WATR) of NASA Ames Research Center (ARC) is presented in this paper. The three WATR facilities are discussed, and three WATR elements - mission control centerns, communications systems, real-time processing and display systems, and tracking systems -are reviewed. The relationships within the NASA WATR, with respect to the NASA aeronautics program, are also discussed.

  20. A cumulative index to Aeronautical Engineering: A special bibliography

    NASA Technical Reports Server (NTRS)

    1978-01-01

    This publication is a cumulative index to the abstracts contained in NASA SP-7037 (80) through NASA SP-7037 (91) of Aeronautical Engineering: A Special Bibliography. NASA SP-7037 and its supplements have been compiled through the cooperative efforts of the American Institute of Aeronautics (AIAA) and Space Administration (NASA). This cumulative index includes subject, personal author, corporate source, contract, and report number indexes.

  1. Aeronautical Engineering: A Continuing Bibliography With Indexes. Supplement 392

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This report lists reports, articles and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles.

  2. NASA's Role in Aeronautics: A Workshop. Volume VII - Background Papers.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Assembly of Engineering.

    Sixteen background papers presented to a plenary session at a 1980 workshop on the role of the National Aeronautics and Space Administration (NASA) in aeronautics are presented. The central task of the workshop was to examine the relationship of NASA's research capabilities to the state of U.S. aviation and to make recommendations about NASA's…

  3. Aeronautical engineering: A continuing bibliography with indexes (supplement 310)

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This bibliography lists 29 reports, articles, and other documents introduced into the NASA scientific and technical information system in Nov. 1994. Subject coverage includes: engineering and theoretical aspects of design, construction,evaluation testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles.

  4. 14 CFR 61.159 - Aeronautical experience: Airplane category rating.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... rating. 61.159 Section 61.159 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Transport Pilots § 61.159 Aeronautical experience: Airplane category rating. (a) Except as provided in... certificate with an airplane category and class rating must have at least 1,500 hours of total time as a...

  5. 14 CFR 61.159 - Aeronautical experience: Airplane category rating.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... rating. 61.159 Section 61.159 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Transport Pilots § 61.159 Aeronautical experience: Airplane category rating. (a) Except as provided in... certificate with an airplane category and class rating must have at least 1,500 hours of total time as a...

  6. 14 CFR 61.159 - Aeronautical experience: Airplane category rating.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... rating. 61.159 Section 61.159 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Transport Pilots § 61.159 Aeronautical experience: Airplane category rating. (a) Except as provided in... certificate with an airplane category and class rating must have at least 1,500 hours of total time as a...

  7. 14 CFR 61.159 - Aeronautical experience: Airplane category rating.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... rating. 61.159 Section 61.159 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Transport Pilots § 61.159 Aeronautical experience: Airplane category rating. (a) Except as provided in... certificate with an airplane category and class rating must have at least 1,500 hours of total time as a...

  8. Aeronautical engineering: A continuing bibliography with indexes (supplement 324)

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This bibliography lists 149 reports, articles, and other documents introduced into the NASA scientific and technical information system in December 1995. Subject coverage includes engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles.

  9. Aeronautical Engineering: A Continuing Bibliography with Indexes. SUPPL-422

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This report lists reports, articles and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles.

  10. Aeronautical engineering: A continuing bibliography with indexes (supplement 319)

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This report lists 349 reports, articles and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles.

  11. Aeronautics and Space Report of the President: 1977 Activities.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    The national programs in aeronautics and space made steady progress in 1977 toward their long-term objectives. In aeronautics the goals were improved performance, energy efficiency, and safety in aircraft. In space the goals were: (1) better remote sensing systems to generate more sophisticated information about the Earth's environment; (2)…

  12. 49 CFR 192.723 - Distribution systems: Leakage surveys.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Distribution systems: Leakage surveys. 192.723... Distribution systems: Leakage surveys. (a) Each operator of a distribution system shall conduct periodic leakage surveys in accordance with this section. (b) The type and scope of the leakage control...

  13. 49 CFR 192.723 - Distribution systems: Leakage surveys.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Distribution systems: Leakage surveys. 192.723... Distribution systems: Leakage surveys. (a) Each operator of a distribution system shall conduct periodic leakage surveys in accordance with this section. (b) The type and scope of the leakage control...

  14. 49 CFR 192.723 - Distribution systems: Leakage surveys.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Distribution systems: Leakage surveys. 192.723... Distribution systems: Leakage surveys. (a) Each operator of a distribution system shall conduct periodic leakage surveys in accordance with this section. (b) The type and scope of the leakage control...

  15. 49 CFR 192.723 - Distribution systems: Leakage surveys.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Distribution systems: Leakage surveys. 192.723... Distribution systems: Leakage surveys. (a) Each operator of a distribution system shall conduct periodic leakage surveys in accordance with this section. (b) The type and scope of the leakage control...

  16. 21 CFR 870.2640 - Portable leakage current alarm.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Portable leakage current alarm. 870.2640 Section... leakage current alarm. (a) Identification. A portable leakage current alarm is a device used to measure the electrical leakage current between any two points of an electrical system and to sound an alarm...

  17. 21 CFR 870.2640 - Portable leakage current alarm.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Portable leakage current alarm. 870.2640 Section... leakage current alarm. (a) Identification. A portable leakage current alarm is a device used to measure the electrical leakage current between any two points of an electrical system and to sound an alarm...

  18. 21 CFR 870.2640 - Portable leakage current alarm.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Portable leakage current alarm. 870.2640 Section... leakage current alarm. (a) Identification. A portable leakage current alarm is a device used to measure the electrical leakage current between any two points of an electrical system and to sound an alarm...

  19. 21 CFR 870.2640 - Portable leakage current alarm.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Portable leakage current alarm. 870.2640 Section... leakage current alarm. (a) Identification. A portable leakage current alarm is a device used to measure the electrical leakage current between any two points of an electrical system and to sound an alarm...

  20. 21 CFR 870.2640 - Portable leakage current alarm.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Portable leakage current alarm. 870.2640 Section... leakage current alarm. (a) Identification. A portable leakage current alarm is a device used to measure the electrical leakage current between any two points of an electrical system and to sound an alarm...

  1. Aeronautical engineering: A continuing bibliography with indexes (supplement 294)

    NASA Technical Reports Server (NTRS)

    1993-01-01

    This issue of Aeronautical Engineering - A Continuing Bibliography with Indexes lists 590 reports, journal articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspect of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. The bibliographic series is compiled through the cooperative efforts of the American Institute of Aeronautics and Astronautics (AIAA) and the National Aeronautics and Space Administration (NASA). Seven indexes are included: subject, personal author, corporate source, foreign technology, contract number, report number, and accession number.

  2. Determination of leakage areas in nuclear piping

    SciTech Connect

    Keim, E.

    1997-04-01

    For the design and operation of nuclear power plants the Leak-Before-Break (LBB) behavior of a piping component has to be shown. This means that the length of a crack resulting in a leak is smaller than the critical crack length and that the leak is safely detectable by a suitable monitoring system. The LBB-concept of Siemens/KWU is based on computer codes for the evaluation of critical crack lengths, crack openings, leakage areas and leakage rates, developed by Siemens/KWU. In the experience with the leak rate program is described while this paper deals with the computation of crack openings and leakage areas of longitudinal and circumferential cracks by means of fracture mechanics. The leakage areas are determined by the integration of the crack openings along the crack front, considering plasticity and geometrical effects. They are evaluated with respect to minimum values for the design of leak detection systems, and maximum values for controlling jet and reaction forces. By means of fracture mechanics LBB for subcritical cracks has to be shown and the calculation of leakage areas is the basis for quantitatively determining the discharge rate of leaking subcritical through-wall cracks. The analytical approach and its validation will be presented for two examples of complex structures. The first one is a pipe branch containing a circumferential crack and the second one is a pipe bend with a longitudinal crack.

  3. Extensive paternal mtDNA leakage in natural populations of Drosophila melanogaster

    PubMed Central

    Nunes, Maria D S; Dolezal, Marlies; Schlötterer, Christian

    2013-01-01

    Strict maternal inheritance is considered a hallmark of animal mtDNA. Although recent reports suggest that paternal leakage occurs in a broad range of species, it is still considered an exceptionally rare event. To evaluate the impact of paternal leakage on the evolution of mtDNA, it is essential to reliably estimate the frequency of paternal leakage in natural populations. Using allele-specific real-time quantitative PCR (RT-qPCR), we show that heteroplasmy is common in natural populations with at least 14% of the individuals carrying multiple mitochondrial haplotypes. However, the average frequency of the minor mtDNA haplotype is low (0.8%), which suggests that this pervasive heteroplasmy has not been noticed before due to a lack of power in sequencing surveys. Based on the distribution of mtDNA haplotypes in the offspring of heteroplasmic mothers, we found no evidence for strong selection against one of the haplotypes. We estimated that the rate of paternal leakage is 6% and that at least 100 generations are required for complete sorting of mtDNA haplotypes. Despite the high proportion of heteroplasmic individuals in natural populations, we found no evidence for recombination between mtDNA molecules, suggesting that either recombination is rare or recombinant haplotypes are counter-selected. Our results indicate that evolutionary studies using mtDNA as a marker might be biased by paternal leakage in this species. PMID:23452233

  4. Air leakage in residential solar heating systems

    NASA Astrophysics Data System (ADS)

    Shingleton, J. G.; Cassel, D. E.; Overton, R. L.

    1981-02-01

    A series of computer simulations was performed to evaluate the effects of component air leakage on system thermal performance for a typical residential solar heating system, located in Madison, Wisconsin. Auxiliary energy required to supplement solar energy for space heating was determined using the TRNSYS computer program, for a range of air leakage rates at the solar collector and pebble bed storage unit. The effects of heat transfer and mass transfer between the solar equipment room and the heated building were investigated. The effect of reduced air infiltration into the building due to pressurized by the solar air heating system were determined. A simple method of estimating the effect of collector array air leakage on system thermal performance was evaluated, using the f CHART method.

  5. Leakage Sign for Primary Intracerebral Hemorrhage

    PubMed Central

    Hirohata, Masaru; Nakamura, Yukihiko; Takeshige, Nobuyuki; Aoki, Takachika; Hattori, Gousuke; Sakata, Kiyohiko; Abe, Toshi; Uchiyama, Yuusuke; Sakamoto, Teruo; Morioka, Motohiro

    2016-01-01

    Background and Purpose— Recent studies of intracerebral hemorrhage treatments have highlighted the need to identify reliable predictors of hematoma expansion. Several studies have suggested that the spot sign on computed tomographic angiography (CTA) is a sensitive radiological predictor of hematoma expansion in the acute phase. However, the spot sign has low sensitivity for hematoma expansion. In this study, we evaluated the usefulness of a novel predictive method, called the leakage sign. Methods— We performed CTA for 80 consecutive patients presenting with spontaneous intracerebral hemorrhage. Two scans were completed: CTA phase and delayed phase (5 minutes after the CTA phase). By comparing the CTA phase images, we set a region of interest with a 10-mm diameter and calculated the Hounsfield units. We defined a positive leakage sign as a >10% increase in Hounsfield units in the region of interest. Additionally, hematoma expansion was determined on plain computed tomography at 24 hours in patients who did not undergo emergent surgery. Results— Positive spot signs and leakage signs were present in 18 (22%) patients and 35 (43%) patients, respectively. The leakage sign had higher sensitivity (93.3%) and specificity (88.9%) for hematoma expansion than the spot sign. The leakage sign, but not the spot sign, was significantly related with poor outcomes (severely disabled, vegetative state, and death) in all of the patients (P=0.03) and in patients with a hemorrhage in the putamen (P=0.0016). Conclusions— The results indicate that the leakage sign is a useful and sensitive method to predict hematoma expansion. PMID:26931155

  6. Inward leakage in tight-fitting PAPRs.

    PubMed

    Koh, Frank C; Johnson, Arthur T; Rehak, Timothy E

    2011-01-01

    A combination of local flow measurement techniques and fog flow visualization was used to determine the inward leakage for two tight-fitting powered air-purifying respirators (PAPRs), the 3M Breathe-Easy PAPR and the SE 400 breathing demand PAPR. The PAPRs were mounted on a breathing machine head form, and flows were measured from the blower and into the breathing machine. Both respirators leaked a little at the beginning of inhalation, probably through their exhalation valves. In both cases, the leakage was not enough for fog to appear at the mouth of the head form. PMID:21647352

  7. Inward Leakage in Tight-Fitting PAPRs

    PubMed Central

    Koh, Frank C.; Johnson, Arthur T.; Rehak, Timothy E.

    2011-01-01

    A combination of local flow measurement techniques and fog flow visualization was used to determine the inward leakage for two tight-fitting powered air-purifying respirators (PAPRs), the 3M Breathe-Easy PAPR and the SE 400 breathing demand PAPR. The PAPRs were mounted on a breathing machine head form, and flows were measured from the blower and into the breathing machine. Both respirators leaked a little at the beginning of inhalation, probably through their exhalation valves. In both cases, the leakage was not enough for fog to appear at the mouth of the head form. PMID:21647352

  8. An Overview of the NASA Aeronautics Test Program Strategic Plan

    NASA Technical Reports Server (NTRS)

    Marshall, Timothy J.

    2010-01-01

    U.S. leadership in aeronautics depends on ready access to technologically advanced, efficient, and affordable aeronautics test capabilities. These systems include major wind tunnels and propulsion test facilities and flight test capabilities. The federal government owns the majority of the major aeronautics test capabilities in the United States, primarily through the National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD), however an overarching strategy for management of these national assets was needed. Therefore, in Fiscal Year (FY) 2006 NASA established the Aeronautics Test Program (ATP) as a two-pronged strategic initiative to: (1) retain and invest in NASA aeronautics test capabilities considered strategically important to the agency and the nation, and (2) establish a strong, high level partnership with the DoD Test Resources Management Center (TRMC), stewards of the DoD test and evaluation infrastructure. Since then, approximately seventy percent of the ATP budget has been directed to underpin fixed and variable costs of facility operations within its portfolio and the balance towards strategic investments in its test facilities, including maintenance and capability upgrades. Also, a strong guiding coalition was established through the National Partnership for Aeronautics Testing (NPAT), with governance by the senior leadership of NASA s Aeronautics Research Mission Directorate (ARMD) and the DoD's TRMC. As part of its strategic planning, ATP has performed or participated in many studies and analyses, including assessments of major NASA and DoD aeronautics test capabilities, test facility condition evaluations and market research. The ATP strategy has also benefitted from unpublished RAND research and analysis by Ant n et al. (2009). Together, these various studies, reports and assessments serve as a foundation for a new, five year strategic plan that will guide ATP through FY 2014. Our vision for the future is a balanced

  9. Astronautics and Aeronautics, 1991-1995: A Chronology

    NASA Technical Reports Server (NTRS)

    Gawdiak, Ihor Y. (Compiler); Shetland, Charles (Compiler)

    2000-01-01

    This chronology of events in aeronautics, aviation, space science, and space exploration was prepared by the Federal Research Division of the Library of Congress and RSIS for the History Division of the National Aeronautics and Space Administration (NASA). It covers the years 1991-1995 and continues the series of annual chronologies published by NASA. The present volume uses the format of the previous edition of this series, Astronautics and Aeronautics, 1986-1990: A Chronology. It also integrates, in the appendices, information presented in previous publication

  10. NASA's Role in Aeronautics: A Workshop. Volume 7: Background papers

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The nature and implications of the current state of U.S. aviation in a world setting are examined as well as their significance for NASA's role in the nation's aeronautical future. The outlook for the 1980's is examined from the point of view of legislation, economics and finance; petroleum; manpower, metallic materials, general aviation; military aviation; transport aircraft developments; and helicopters. Possible NASA assistance to DOD and the FAA is examined and the evolution of NACA and NASA in aeronautics and of NASA's aeronautics capabilities are described.

  11. Aeronautical Engineering: A Continuing Bibliography With Indexes. Supplement 404

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-1999-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. Two indexes-subject and author are included after the abstract section.

  12. Aeronautics and space report of the president, 1974 activities

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The U.S. Government activities for 1974 in aeronautics and space are presented. Significant contributions toward the fulfillment of the nation's goals in space and aeronautics are covered, including application of space systems and technology to beneficial uses on earth, exploration of space and increase of scientific knowledge, development of improved space systems and technology, international cooperation, and advancement of civil and military aeronautics. Also in 1974, space activities in the private sector expanded to provide additional services to the public. The accomplishments are summarized.

  13. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 386

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-1998-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract.

  14. Aeronautical Engineering: A Continuing Bibliography With Indexes. Supplement 418

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-2000-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. Two indexes-subject and author are included after the abstract section.

  15. Aeronautical Engineering: A Continuing Bibliography With Indexes. Supplement 406

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-1999-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. Two indexes-subject and author are included after the abstract section.

  16. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 389

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-1998-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract.

  17. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 391

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-1999-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract.

  18. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 396

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-1999-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. Two indexes-subject and author are included after the abstract section.

  19. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 413

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-2000-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. Two indexes-subject and author are included after the abstract section.

  20. Astronautics and Aeronautics, 1986-1990: A Chronology

    NASA Technical Reports Server (NTRS)

    Gawdiak, Ihor Y.; Miro, Ramon J.; Stueland, Sam

    1997-01-01

    This chronology of events in aeronautics, aviation, space science, and space exploration was prepared by the Federal Research Division of the LibrarY of Congress for the History Division of the National Aeronautics and Space Administration (NASA). It covers the years 1996-1990 and continues the series of annual chronologies published by NASA. The present volume returns to the format used in the Astronautics and Aeronautics, 1979-1984: A Chronology volume. It also integrates in a single table the information presented in two or three previous publications.

  1. Aeronautical Engineering: A Continuing Bibliography With Indexes. Supplement 398

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This supplemental issue of Aeronautical Engineering lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes - subject and author are included after the abstract section.

  2. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 419

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-2000-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. Two indexes-subject and author are included after the abstract section.

  3. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 420

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-2000-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. Two indexes-subject and author are included after the abstract section.

  4. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 387

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-1998-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract.

  5. A harmonic pulse testing method for leakage detection in deep subsurface storage formations

    NASA Astrophysics Data System (ADS)

    Sun, Alexander Y.; Lu, Jiemin; Hovorka, Susan

    2015-06-01

    Detection of leakage in deep geologic storage formations (e.g., carbon sequestration sites) is a challenging problem. This study investigates an easy-to-implement frequency domain leakage detection technology based on harmonic pulse testing (HPT). Unlike conventional constant-rate pressure interference tests, HPT stimulates a reservoir using periodic injection rates. The fundamental principle underlying HPT-based leakage detection is that leakage modifies a storage system's frequency response function, thus providing clues of system malfunction. During operations, routine HPTs can be conducted at multiple pulsing frequencies to obtain experimental frequency response functions, using which the possible time-lapse changes are examined. In this work, a set of analytical frequency response solutions is derived for predicting system responses with and without leaks for single-phase flow systems. Sensitivity studies show that HPT can effectively reveal the presence of leaks. A search procedure is then prescribed for locating the actual leaks using amplitude and phase information obtained from HPT, and the resulting optimization problem is solved using the genetic algorithm. For multiphase flows, the applicability of HPT-based leakage detection procedure is exemplified numerically using a carbon sequestration problem. Results show that the detection procedure is applicable if the average reservoir conditions in the testing zone stay relatively constant during the tests, which is a working assumption under many other interpretation methods for pressure interference tests. HPT is a cost-effective tool that only requires periodic modification of the nominal injection rate. Thus it can be incorporated into existing monitoring plans with little additional investment.

  6. [Diagnosis of cerebrospinal fluid leakages by gamma-cisternography].

    PubMed

    Oberson, R

    1976-01-01

    Cerebrospinal fluid (CSF) leakages either secondary (traumatic) or spontaneous (non-traumatic) are first considered in their frequency and origin. The exact topography of the various meningeal and cranial lesions involved are difficult to assess particularly in the most important groups of persistant traumatic CSF rhinorrhea and recurrent meningitis. Among the various diagnostic approaches, direct observation is always necessary, but of limited value. Standard X-rays must be followed by multidirectionnal tomography (Polytome) and, whenever available, computed tomodensitography of the base of the skull. Brain pneumography provides a thorough setting fourth of the congenital or acquired cerebral lesions as well as the new cranio-meningeal conditions. Difficulties encountered with the techniques of subdurography and Pantopaque injection are underlined. Three radioisotope techniques are considered. 1) The earlier technique of cotton-pledgets only shows the external orifice. 2) The recent proposal of nuclide cranial subdurography is criticized for ignoring the leptomeningeal bag. 3) Radioisotope cisternography (RIC) or gamma-cisternography is described more precisely. It remains the most complete and appropriate method for observing the natural behaviour of the leakage. RIC with fistulography is performed through suboccipital injection of 99mTc-DTPA. RIC provides essential clues on the relative importance of associated dynamic disturbances of the third circulation and morphological changes of its anatomical bed (stenoses and widenings of the ependymal and leptomeningeal spaces). If present, the leakage may be directly shown on the RIC pictures. If rhinorrhea is abundant, there is no difficulty in assessing side and site of the fistula. If rhinorrhea is occult, dubious or intermittent, diagnosis is often difficult. There are also indirect signs of rhinorrhea: leptomeningeal dilatation near a frontal or ethmoidal fracture, contamination of the rhinopharynx, examination of

  7. NASA Aeronautics and Space Database for bibliometric analysis

    NASA Technical Reports Server (NTRS)

    Powers, R.; Rudman, R.

    2004-01-01

    The authors use the NASA Aeronautics and Space Database to perform bibliometric analysis of citations. This paper explains their research methodology and gives some sample results showing collaboration trends between NASA Centers and other institutions.

  8. The Aeronautical Laboratory of the Stockholm Technical Institute

    NASA Technical Reports Server (NTRS)

    Malmer, Ivar

    1935-01-01

    This report presents a detailed analysis and history of the construction and operation of the aeronautical laboratory of the Stockholm Technical Institute. Engines and balances are discussed and experimental results are also given.

  9. 77 FR 13683 - Government/Industry Aeronautical Charting Forum Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-07

    ... Charting Group, contact Valerie S. Watson, FAA, National Aeronautical Navigation Products (AeroNav Products... permits. Issued in Washington, DC, on February 28, 2012. Valerie S. Watson, Co-Chair,...

  10. National Aeronautics and Space Administration technology application team program

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Contracts are reported between the RTI TATeam and the National Aeronautics and Space Administration (NASA), the Environmental Protection Agency (EPA), and other governmental, educational, and industrial organizations participating in NASA's Technology Utilization Program.

  11. Bureau of Aeronautics, June 5, 1945, Photograph 519. ASERIAL OF ...

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

    Bureau of Aeronautics, June 5, 1945, Photograph 51-9. ASERIAL OF ROOSEVELT BASE, DIRECT OVERHEAD, SHOWING PIERS AND MOLE UNDER CONSTRUCTION - Roosevelt Base, Bounded by Ocean Boulevard, Pennsylvania Avenue, Richardson Avenue, & Idaho Street, Long Beach, Los Angeles County, CA

  12. Bureau of Aeronautics, October 16, 1943, Photograph #4875. AERIAL OF ...

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

    Bureau of Aeronautics, October 16, 1943, Photograph #4875. AERIAL OF ROOSEVELT BASE LOOKING EAST - Roosevelt Base, Bounded by Ocean Boulevard, Pennsylvania Avenue, Richardson Avenue, & Idaho Street, Long Beach, Los Angeles County, CA

  13. Aeronautical Engineering: A continuing bibliography with indexes (supplement 175)

    NASA Technical Reports Server (NTRS)

    1984-01-01

    This bibliography lists 467 reports, articles and other documents introduced into the NASA scientific and technical information system in May 1984. Topics cover varied aspects of aeronautical engineering, geoscience, physics, astronomy, computer science, and support facilities.

  14. Astronautics and Aeronautics, 1979-1984: A chronology

    NASA Technical Reports Server (NTRS)

    Janson, Bette R.; Ritchie, Eleanor H.

    1989-01-01

    This volume of the Astronautics and Aeronautics series covers 1979 through 1984. The series provides a chronological presentation of all significant events and developments in space exploration and the administration of the space program during the period covered.

  15. NASA's Role in Aeronautics: A Workshop. Volume 1: Summary

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The state of the U.S. aeronautic industry and progressive changes in national priorities as reflected in federal unified budget outlays are reviewed as well as the contribution of NACA and the character and substance of U.S. aeronautical research under NASA. Eight possible roles for the future defined by NASA are examined and the extent to which the agency should carry out these activities is considered. The roles include: (1) national facilities expertise; (2) flight sciences research; (3) generic technology evolution; (4) vehicle class evolution; (5) technology demonstration; (6) prototype development; (7) technology validation; and (8) operations feasibility; How NASA's roles varies in the areas of military aviation, general aviation, transport aircraft aeronautics, rotorcraft aeronautics, engineering education, information dissemination, and cooperation with other organizations and agencies is discussed with regard to research in aerodynamics; structures and materials; propulsion; electronics and avionics; vehicle operations; and human engineering.

  16. Vacuum test fixture improves leakage rate measurements

    NASA Technical Reports Server (NTRS)

    Maier, H.; Marx, H.

    1966-01-01

    Cylindrical chamber, consisting of two matching halves, forms a vacuum test fixture for measuring leakage rates of individual connections, brazed joints, and entrance ports used in closed fluid flow line systems. Once the chamber has been sufficiently evacuated, atmospheric pressure holds the two halves together.

  17. Imaging inflammatory plasma leakage in vivo.

    PubMed

    Kenne, E; Lindbom, L

    2011-05-01

    Increased vascular permeability and consequent plasma leakage from postcapillary venules is a cardinal sign of inflammation. Although the movement of plasma constituents from the vasculature to the affected tissue aids in clearing the inflammatory stimulus, excessive plasma extravasation can lead to hospitalisation or death in cases such as influenza-induced pneumonia, burns or brain injury. The use of intravital imaging has significantly contributed to the understanding of the mechanisms controlling the vascular permeability alterations that occur during inflammation. Today, intravital imaging can be performed using optical and non-optical techniques. Optical techniques, which are generally used in experimental settings, include traditional intravital fluorescence microscopy and near-infrared fluorescence imaging. Magnetic resonance (MRI) and radioisotopic imaging are used mainly in the clinical setting, but are increasingly used in experimental work, and can detect plasma leakage without optics. Although these methods are all able to visualise inflammatory plasma leakage in vivo, the spatial and temporal resolution differs between the techniques. In addition, they vary with regards to invasiveness and availability. This overview discusses the use of imaging techniques in the visualisation of inflammatory plasma leakage. PMID:21437352

  18. Measurements of the atmospheric neutron leakage rate

    NASA Technical Reports Server (NTRS)

    Lockwood, J. A.; Ifedili, S. O.; Jenkins, R. W.

    1973-01-01

    The atmospheric neutron leakage rate in the energy range from 0.01 to 10,000,000 eV has been measured as a function of latitude, altitude, and time with a neutron detector on board the Ogo 6 satellite. The latitude dependence of the neutron leakage is in reasonable agreement with that predicted by Lingenfelter (1963) and Light et al. (1973) if the neutron energy spectrum has the shape calculated by Newkirk (1963). The change in the neutron latitude dependence with the cosmic ray modulation agrees with the predictions of Lingenfelter and Light et al. For several solar proton events enhancements were observed in the neutron counting rates at lambda greater than or equal to 70 deg. Such events, however, provide an insignificant injection of protons at E less than or equal to 20 MeV into the radiation belts. An isotropic angular distribution of the neutron leakage in the energy range from 0.1 keV to 10 MeV best fits the observed altitude dependence of the neutron leakage flux.

  19. 49 CFR 230.78 - Leakage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of 3 psi per minute in a test of 3 minutes duration that is made after the pressure has been reduced to 60 percent of the maximum operating pressure. (b) Brake cylinders. Leakage from brake cylinders... pipe pressure, and with communication to the brake cylinders closed, the brakes on the steam...

  20. 49 CFR 230.78 - Leakage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of 3 psi per minute in a test of 3 minutes duration that is made after the pressure has been reduced to 60 percent of the maximum operating pressure. (b) Brake cylinders. Leakage from brake cylinders... pipe pressure, and with communication to the brake cylinders closed, the brakes on the steam...

  1. Control of Air Leakage in Buildings.

    ERIC Educational Resources Information Center

    Wilson, A. Grant

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

  2. Aeronautical Engineering, a special bibliography with indexes, supplement 15

    NASA Technical Reports Server (NTRS)

    1972-01-01

    This special bibliography lists 363 reports, articles, and other documents introduced into the NASA scientific and technical information system in January 1972. Emphasis is placed on engineering and theoretical aspects for design, construction, evaluation, testing, operation and performance of aircraft (including aircraft engines) and associated components, equipment and systems. Also included are entries on research and development in aeronautics and aerodynamics and research and ground support for aeronautical vehicles.

  3. First Semiannual Report of the National Aeronautics and Space Administration

    NASA Technical Reports Server (NTRS)

    Glennan, T. Keith

    1959-01-01

    The First Semiannual Report of the National Aeronautics and Space Administration (NASA) is submitted to Congress pursuant to section 206 (a) of the National Aeronautics and Space Act of 1958 (Public Law 85-568) to provide for research into problems of flight within and outside the Earth's atmosphere, which states: The Administration shall submit to the President for transmittal to Congress, semiannually and at such other times as it deems desirable, a report on its activities and accomplishments.

  4. Aeronautical engineering: A continuing bibliography with indexes (supplement 282)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This bibliography lists 623 reports, articles, and other documents introduced into the NASA scientific and technical information system in Aug. 1992. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles.

  5. A Vision in Aeronautics: The K-12 Wind Tunnel Project

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A Vision in Aeronautics, a project within the NASA Lewis Research Center's Information Infrastructure Technologies and Applications (IITA) K-12 Program, employs small-scale, subsonic wind tunnels to inspire students to explore the world of aeronautics and computers. Recently, two educational K-12 wind tunnels were built in the Cleveland area. During the 1995-1996 school year, preliminary testing occurred in both tunnels.

  6. Aeronautical engineering: A continuing bibliography with indexes (supplement 119)

    NASA Technical Reports Server (NTRS)

    1980-01-01

    This bibliography lists 341 reports, articles, and other documents introduced into the NASA scientific and technical information system in January 1980. Abstracts on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems are presented. Research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles are also presented.

  7. Aeronautical Engineering: A special bibliography with indexes, supplement 13

    NASA Technical Reports Server (NTRS)

    1972-01-01

    This special bibliography lists 283 reports, articles, and other documents introduced into the NASA scientific and technical information system in December, 1971. Emphasis is placed on engineering and theoretical aspects for design, construction, evaluation, testing, operation and performance of aircraft (including aircraft engines), and associated components, equipment and systems. Also included are entries on research and development in aeronautics and aerodynamics and research and ground support for aeronautical vehicles.

  8. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 397

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This report lists reports, articles and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract.

  9. Kennedy Educate to Innovate (KETI) Aeronautics PowerPoint Presentation

    NASA Technical Reports Server (NTRS)

    Davila, Dina

    2010-01-01

    This slide presentation reviews some fundamental features of aeronautics. It is designed to introduce students to aeronautics and to engage them in Science Technology Education and Mathematics (STEM). It reviews the history of airflight, the aircraft components and their interaction with the forces that make flight possible (i.e. lift, weight drag and thrust), and the interaction of the components that create aircraft movements (roll, pitch and yaw)

  10. NASA Ames and Future of Space Exploration, Science, and Aeronautics

    NASA Technical Reports Server (NTRS)

    Cohen, Jacob

    2015-01-01

    Pushing the frontiers of aeronautics and space exploration presents multiple challenges. NASA Ames Research Center is at the forefront of tackling these issues, conducting cutting edge research in the fields of air traffic management, entry systems, advanced information technology, intelligent human and robotic systems, astrobiology, aeronautics, space, earth and life sciences and small satellites. Knowledge gained from this research helps ensure the success of NASA's missions, leading us closer to a world that was only imagined as science fiction just decades ago.

  11. 47 CFR 87.217 - Frequencies.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Frequencies. 87.217 Section 87.217... Aeronautical Advisory Stations (Unicoms) § 87.217 Frequencies. (a) Only one unicom frequency will be assigned at any one airport. Applicants must request a particular frequency, which will be taken...

  12. 47 CFR 87.217 - Frequencies.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Frequencies. 87.217 Section 87.217... Aeronautical Advisory Stations (Unicoms) § 87.217 Frequencies. (a) Only one unicom frequency will be assigned at any one airport. Applicants must request a particular frequency, which will be taken...

  13. 47 CFR 87.217 - Frequencies.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequencies. 87.217 Section 87.217... Aeronautical Advisory Stations (Unicoms) § 87.217 Frequencies. (a) Only one unicom frequency will be assigned at any one airport. Applicants must request a particular frequency, which will be taken...

  14. 47 CFR 87.217 - Frequencies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 87.217 Section 87.217... Aeronautical Advisory Stations (Unicoms) § 87.217 Frequencies. (a) Only one unicom frequency will be assigned at any one airport. Applicants must request a particular frequency, which will be taken...

  15. 47 CFR 87.217 - Frequencies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Frequencies. 87.217 Section 87.217... Aeronautical Advisory Stations (Unicoms) § 87.217 Frequencies. (a) Only one unicom frequency will be assigned at any one airport. Applicants must request a particular frequency, which will be taken...

  16. Pipeline leakage detection using distributed fibre optical temperature sensing

    NASA Astrophysics Data System (ADS)

    Grosswig, S.; Hurtig, E.; Luebbecke, S.; Vogel, B.

    2005-05-01

    The leakage detection system based on the distributed fibre optical temperature measurement method is an analysing method for continuous detection and localization of leakages at pipelines in the steady and unsteady operation states according to the German rules for pipelines TRbF 301/TRFL which is valid in Germany since April 2003. The leakage detection system is useable under the precondition that there is a sufficient large temperature gradient between the leakage area and the unaffected environment. This can be caused by the medium itself or through a physical effect due to the leakage, e.g. gas expansion, evaporation. It's a very sensitive method, so also creeping leakages can be detected.

  17. 78 FR 36013 - Public Notice for Waiver of Aeronautical Land-Use Assurance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-14

    ... Federal Aviation Administration Public Notice for Waiver of Aeronautical Land-Use Assurance AGENCY....03-acre portion of Parcel AA of airport land from aeronautical use to non- aeronautical use (for... surfaces and compatible land use. The change from aeronautical to non-aeronautical use would allow...

  18. Dynamic SVL and body bias for low leakage power and high performance in CMOS digital circuits

    NASA Astrophysics Data System (ADS)

    Deshmukh, Jyoti; Khare, Kavita

    2012-12-01

    In this article, a new complementary metal oxide semiconductor design scheme called dynamic self-controllable voltage level (DSVL) is proposed. In the proposed scheme, leakage power is controlled by dynamically disconnecting supply to inactive blocks and adjusting body bias to further limit leakage and to maintain performance. Leakage power measurements at 1.8 V, 75°C demonstrate power reduction by 59.4% in case of 1 bit full adder and by 43.0% in case of a chain of four inverters using SVL circuit as a power switch. Furthermore, we achieve leakage power reduction by 94.7% in case of 1 bit full adder and by 91.8% in case of a chain of four inverters using dynamic body bias. The forward body bias of 0.45 V applied in active mode improves the maximum operating frequency by 16% in case of 1 bit full adder and 5.55% in case of a chain of inverters. Analysis shows that additional benefits of using the DSVL and body bias include high performance, low leakage power consumption in sleep mode, single threshold implementation and state retention even in standby mode.

  19. Investigation of Turbulent Tip Leakage Vortex in an Axial Water Jet Pump with Large Eddy Simulation

    NASA Technical Reports Server (NTRS)

    Hah, Chunill; Katz, Joseph

    2012-01-01

    Detailed steady and unsteady numerical studies were performed to investigate tip clearance flow in an axial water jet pump. The primary objective is to understand physics of unsteady tip clearance flow, unsteady tip leakage vortex, and cavitation inception in an axial water jet pump. Steady pressure field and resulting steady tip leakage vortex from a steady flow analysis do not seem to explain measured cavitation inception correctly. The measured flow field near the tip is unsteady and measured cavitation inception is highly transient. Flow visualization with cavitation bubbles shows that the leakage vortex is oscillating significantly and many intermittent vortex ropes are present between the suction side of the blade and the tip leakage core vortex. Although the flow field is highly transient, the overall flow structure is stable and a characteristic frequency seems to exist. To capture relevant flow physics as much as possible, a Reynolds-averaged Navier-Stokes (RANS) calculation and a Large Eddy Simulation (LES) were applied for the current investigation. The present study reveals that several vortices from the tip leakage vortex system cross the tip gap of the adjacent blade periodically. Sudden changes in local pressure field inside tip gap due to these vortices create vortex ropes. The instantaneous pressure filed inside the tip gap is drastically different from that of the steady flow simulation. Unsteady flow simulation which can calculate unsteady vortex motion is necessary to calculate cavitation inception accurately even at design flow condition in such a water jet pump.

  20. 40 CFR 91.324 - Analyzer leakage check.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Analyzer leakage check. (a) Vacuum side leak check. (1) Check any location within the analysis system where a vacuum leak could affect the test results. (2) The maximum allowable leakage rate on the...

  1. 40 CFR 91.324 - Analyzer leakage check.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Analyzer leakage check. (a) Vacuum side leak check. (1) Check any location within the analysis system where a vacuum leak could affect the test results. (2) The maximum allowable leakage rate on the...

  2. 40 CFR 91.324 - Analyzer leakage check.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Analyzer leakage check. (a) Vacuum side leak check. (1) Check any location within the analysis system where a vacuum leak could affect the test results. (2) The maximum allowable leakage rate on the...

  3. 40 CFR 91.324 - Analyzer leakage check.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Analyzer leakage check. (a) Vacuum side leak check. (1) Check any location within the analysis system where a vacuum leak could affect the test results. (2) The maximum allowable leakage rate on the...

  4. 40 CFR 91.324 - Analyzer leakage check.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Analyzer leakage check. (a) Vacuum side leak check. (1) Check any location within the analysis system where a vacuum leak could affect the test results. (2) The maximum allowable leakage rate on the...

  5. Trending of Overboard Leakage of ISS Cabin Atmosphere

    NASA Technical Reports Server (NTRS)

    Schaezler, Ryan N.; Cook, Anthony J.; Leonard, Daniel J.; Ghariani, Ahmed

    2011-01-01

    The International Space Station (ISS) overboard leakage of cabin atmosphere is continually tracked to identify new or aggravated leaks and to provide information for planning of nitrogen supply to the ISS. The overboard leakage is difficult to trend with various atmosphere constituents being added and removed. Changes to nitrogen partial pressure is the nominal means of trending the overboard leakage. This paper summarizes the method of the overboard leakage trending and presents findings from the trending.

  6. Radiation induced inter-device leakage degradation

    NASA Astrophysics Data System (ADS)

    Hu, Zhi-Yuan; Liu, Zhang-Li; Shao, Hua; Zhang, Zheng-Xuan; Ning, Bing-Xu; Chen, Ming; Bi, Da-Wei; Zou, Shi-Chang

    2011-08-01

    The evolution of inter-device leakage current with total ionizing dose in transistors in 180 nm generation technologies is studied with an N-type poly-gate field device (PFD) that uses the shallow trench isolation as an effective gate oxide. The overall radiation response of these structures is determined by the trapped charge in the oxide. The impacts of different bias conditions during irradiation on the inter-device leakage current are studied for the first time in this work, which demonstrates that the worst condition is the same as traditional NMOS transistors. Moreover, the two-dimensional technology computer-aided design simulation is used to understand the bias dependence.

  7. 42 CFR 84.92 - Exhalation valve leakage test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Exhalation valve leakage test. 84.92 Section 84.92... Breathing Apparatus § 84.92 Exhalation valve leakage test. (a) Dry exhalation valves and valve seats will be...) Leakage between the valve and the valve seat shall not exceed 30 milliliters per minute....

  8. 42 CFR 84.92 - Exhalation valve leakage test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Exhalation valve leakage test. 84.92 Section 84.92... Breathing Apparatus § 84.92 Exhalation valve leakage test. (a) Dry exhalation valves and valve seats will be...) Leakage between the valve and the valve seat shall not exceed 30 milliliters per minute....

  9. 42 CFR 84.92 - Exhalation valve leakage test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Exhalation valve leakage test. 84.92 Section 84.92... Breathing Apparatus § 84.92 Exhalation valve leakage test. (a) Dry exhalation valves and valve seats will be...) Leakage between the valve and the valve seat shall not exceed 30 milliliters per minute....

  10. 42 CFR 84.92 - Exhalation valve leakage test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Exhalation valve leakage test. 84.92 Section 84.92... Breathing Apparatus § 84.92 Exhalation valve leakage test. (a) Dry exhalation valves and valve seats will be...) Leakage between the valve and the valve seat shall not exceed 30 milliliters per minute....

  11. 42 CFR 84.92 - Exhalation valve leakage test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Exhalation valve leakage test. 84.92 Section 84.92... Breathing Apparatus § 84.92 Exhalation valve leakage test. (a) Dry exhalation valves and valve seats will be...) Leakage between the valve and the valve seat shall not exceed 30 milliliters per minute....

  12. 49 CFR 192.706 - Transmission lines: Leakage surveys.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Transmission lines: Leakage surveys. 192.706... Transmission lines: Leakage surveys. Leakage surveys of a transmission line must be conducted at intervals not exceeding 15 months, but at least once each calendar year. However, in the case of a transmission line...

  13. 49 CFR 192.706 - Transmission lines: Leakage surveys.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Transmission lines: Leakage surveys. 192.706... Transmission lines: Leakage surveys. Leakage surveys of a transmission line must be conducted at intervals not exceeding 15 months, but at least once each calendar year. However, in the case of a transmission line...

  14. 49 CFR 192.706 - Transmission lines: Leakage surveys.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Leakage surveys. 192.706... Transmission lines: Leakage surveys. Leakage surveys of a transmission line must be conducted at intervals not exceeding 15 months, but at least once each calendar year. However, in the case of a transmission line...

  15. 49 CFR 192.706 - Transmission lines: Leakage surveys.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Transmission lines: Leakage surveys. 192.706... Transmission lines: Leakage surveys. Leakage surveys of a transmission line must be conducted at intervals not exceeding 15 months, but at least once each calendar year. However, in the case of a transmission line...

  16. 49 CFR 192.706 - Transmission lines: Leakage surveys.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Transmission lines: Leakage surveys. 192.706... Transmission lines: Leakage surveys. Leakage surveys of a transmission line must be conducted at intervals not exceeding 15 months, but at least once each calendar year. However, in the case of a transmission line...

  17. 78 FR 13383 - Public Availability of the National Aeronautics and Space Administration FY 2012 Service Contract...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-27

    ... SPACE ADMINISTRATION Public Availability of the National Aeronautics and Space Administration FY 2012 Service Contract Inventory (SCI) AGENCY: Office of Procurement, National Aeronautics and Space... National Aeronautics and Space Administration (NASA) is publishing this notice to advise the public of...

  18. 78 FR 22024 - Twenty First Meeting: RTCA Special Committee 216, Aeronautical Systems Security (Joint Meeting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-12

    ... Federal Aviation Administration Twenty First Meeting: RTCA Special Committee 216, Aeronautical Systems... of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 216, Aeronautical Systems... of the twenty first meeting of RTCA Special Committee 216, Aeronautical Systems Security...

  19. 78 FR 5242 - 32nd Meeting: RTCA Special Committee 206, Aeronautical Information and Meteorological Data Link...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-24

    ... Federal Aviation Administration 32nd Meeting: RTCA Special Committee 206, Aeronautical Information and... Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 206, Aeronautical Information and...-second meeting of the RTCA Special Committee 206, Aeronautical Information and Meteorological Data...

  20. 78 FR 8684 - Fifteenth Meeting: RTCA Special Committee 217-Aeronautical Databases Joint with EUROCAE WG-44...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-06

    ... Federal Aviation Administration Fifteenth Meeting: RTCA Special Committee 217--Aeronautical Databases Joint with EUROCAE WG-44--Aeronautical Databases AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 217--Aeronautical...

  1. 78 FR 25134 - Sixteenth Meeting: RTCA Special Committee 217-Aeronautical Databases Joint With EUROCAE WG-44...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-29

    ... Federal Aviation Administration Sixteenth Meeting: RTCA Special Committee 217--Aeronautical Databases Joint With EUROCAE WG-44--Aeronautical Databases AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 217--Aeronautical...

  2. 78 FR 51809 - Seventeenth Meeting: RTCA Special Committee 217-Aeronautical Databases Joint With EUROCAE WG-44...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-21

    ... Federal Aviation Administration Seventeenth Meeting: RTCA Special Committee 217--Aeronautical Databases Joint With EUROCAE WG-44--Aeronautical Databases AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 217--Aeronautical...

  3. 78 FR 66418 - Eighteenth Meeting: RTCA Special Committee 217-Aeronautical Databases Joint With EUROCAE WG-44...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-05

    ... Federal Aviation Administration Eighteenth Meeting: RTCA Special Committee 217--Aeronautical Databases Joint With EUROCAE WG-44--Aeronautical Databases AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 217--Aeronautical...

  4. 78 FR 7816 - NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems Subcommittee Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems... Aeronautics and Space Administration announces a meeting of the Unmanned Aircraft Systems (UAS)...

  5. 78 FR 25100 - NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems Subcommittee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-29

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems... Aeronautics and Space Administration announces a meeting of the Unmanned Aircraft Systems (UAS)...

  6. 77 FR 59020 - NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems Subcommittee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-25

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems... Aeronautics and Space Administration announces a meeting of the Unmanned Aircraft Systems (UAS)...

  7. 76 FR 75565 - NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems (UAS) Subcommittee Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-02

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems (UAS) Subcommittee Meeting AGENCY: National Aeronautics and Space Administration. ACTION: Notice of Meeting....

  8. 3DHZETRN: Neutron leakage in finite objects

    NASA Astrophysics Data System (ADS)

    Wilson, John W.; Slaba, Tony C.; Badavi, Francis F.; Reddell, Brandon D.; Bahadori, Amir A.

    2015-11-01

    The 3DHZETRN formalism was recently developed as an extension to HZETRN with an emphasis on 3D corrections for neutrons and light ions. Comparisons to Monte Carlo (MC) simulations were used to verify the 3DHZETRN methodology in slab and spherical geometry, and it was shown that 3DHZETRN agrees with MC codes to the degree that various MC codes agree among themselves. One limitation of such comparisons is that all of the codes (3DHZETRN and three MC codes) utilize different nuclear models/databases; additionally, using a common nuclear model is impractical due to the complexity of the software. It is therefore difficult to ascertain if observed discrepancies are caused by transport code approximations or nuclear model differences. In particular, an important simplification in the 3DHZETRN formalism assumes that neutron production cross sections can be represented as the sum of forward and isotropic components, where the forward component is subsequently solved within the straight-ahead approximation. In the present report, previous transport model results in specific geometries are combined with additional results in related geometries to study neutron leakage using the Webber 1956 solar particle event as a source boundary condition. A ratio is defined to quantify the fractional neutron leakage at a point in a finite object relative to a semi-infinite slab geometry. Using the leakage ratio removes some of the dependence on the magnitude of the neutron production and clarifies the effects of angular scattering and absorption with regard to differences between the models. Discussion is given regarding observed differences between the MC codes and conclusions drawn about the need for further code development. Although the current version of 3DHZETRN is reasonably accurate compared to MC simulations, this study shows that improved leakage estimates can be obtained by replacing the isotropic/straight-ahead approximation with more detailed descriptions.

  9. 3DHZETRN: Neutron leakage in finite objects.

    PubMed

    Wilson, John W; Slaba, Tony C; Badavi, Francis F; Reddell, Brandon D; Bahadori, Amir A

    2015-11-01

    The 3DHZETRN formalism was recently developed as an extension to HZETRN with an emphasis on 3D corrections for neutrons and light ions. Comparisons to Monte Carlo (MC) simulations were used to verify the 3DHZETRN methodology in slab and spherical geometry, and it was shown that 3DHZETRN agrees with MC codes to the degree that various MC codes agree among themselves. One limitation of such comparisons is that all of the codes (3DHZETRN and three MC codes) utilize different nuclear models/databases; additionally, using a common nuclear model is impractical due to the complexity of the software. It is therefore difficult to ascertain if observed discrepancies are caused by transport code approximations or nuclear model differences. In particular, an important simplification in the 3DHZETRN formalism assumes that neutron production cross sections can be represented as the sum of forward and isotropic components, where the forward component is subsequently solved within the straight-ahead approximation. In the present report, previous transport model results in specific geometries are combined with additional results in related geometries to study neutron leakage using the Webber 1956 solar particle event as a source boundary condition. A ratio is defined to quantify the fractional neutron leakage at a point in a finite object relative to a semi-infinite slab geometry. Using the leakage ratio removes some of the dependence on the magnitude of the neutron production and clarifies the effects of angular scattering and absorption with regard to differences between the models. Discussion is given regarding observed differences between the MC codes and conclusions drawn about the need for further code development. Although the current version of 3DHZETRN is reasonably accurate compared to MC simulations, this study shows that improved leakage estimates can be obtained by replacing the isotropic/straight-ahead approximation with more detailed descriptions. PMID:26553635

  10. Remote Sensing And Surface Hydrocarbon Leakage

    NASA Astrophysics Data System (ADS)

    Matthews, M. D.; Jones, V. T.; Richers, D. M.

    1984-08-01

    The Geosat oil and gas test site program stimulated interest in the interaction between surface hydrocarbon concentrations and interpretation of remote sensing data. The test case results suggested that lineaments correspond to avenues of preferential hydrocarbon seepage and that this seepage affects vegetation health and populations at Patrick Draw field in Wyoming and potentially at Lost River field, West Virginia. These two areas were selected for additional surface hydrocarbon surveys in order to test these hypotheses. The Patrick Draw study shows that a zone of stressed vegetation, visible on thematic mapper data, definitely coincides with an area of marked leakage of hydrocarbons and that the composition of these gases would predict an intermediate type oil and gas reservoir such as exists in the area. The study further indicates that the leakage is in large part controlled by the presence of fractures/faults recognized as lineaments on the remote sensing images. The Lost River study specifically investigated the possible existence of hydrocarbon leakage causing anomalous populations of maple trees in a climax oak forest. These maples were first recognized by study of thematic mapper simulator data. The soil gas hydrocarbon concentrations are above average in several of the maple anomalies over the field. This supports the inference that the maples are present because they are more tolerant of soil conditions where hydrocarbon seepage is active. The crest of the field has low soil gas magnitudes, but high values occur to the updip eastern edge of the field along a fault/fracture that was detected in the seismic data. The conclusion that preferential pathways of hydrocarbon leakage are recognized in spectral and textural analysis of remote sensing data is supported by other studies and integrated into a suggested exploration/hydrocarbon migration model.

  11. Atomic Oxygen Effects on Seal Leakage

    NASA Technical Reports Server (NTRS)

    Christensen, John R.; Underwood, Steve D.; Kamenetzky, Rachel R.; Vaughn, Jason A.

    1999-01-01

    Common Berthing Mechanism (CBM provides the structural interface between separate International Space Station (ISS) elements, such as the Laboratory and Node modules. The CBM consists of an active and a passive half that join together with structural bolts. The seal at this interface is the CBM-to-CBM molded seal. The CBM-to-CBM interface is assembled on orbit, thus the seals can be exposed to the space environment for up to 65 hours. Atomic Oxygen/Vacuum Ultraviolet radiation (AO/VUV) in space is a potential hazard to the seals. Testing was conducted to determine the effect on leakage of the CBM-to-CBM seal material exposed to AO/VUV. The sealing materials were S383 silicone and V835 fluorocarbon material. Control samples, which were not exposed to the AO/VUV environment, were used to ensure that ff any changes in leakage occurred, they could be attributed to the AO/VUV exposure. After exposure to the AO/VUV environment the leakage increase was dramatic for the fluorocarbon. This testing was a major contributing factor in selecting silicone as the CBM-to-CBM seal material.

  12. Gaseous hydrogen leakage optical fibre detection system

    NASA Astrophysics Data System (ADS)

    Trouillet, Alain; Veillas, Colette; Sigronde, E.; Gagnaire, Henri; Clement, Michel

    2004-06-01

    Liquid hydrogen has been intensively used in aerospace applications during the past forty years and is of great interest for fuel cells technologies and future automotive applications. Following upon major explosive risks due to the use of hydrogen in air, previous studies were carried out in our laboratory in order to develop optical fiber sensors for the detection of hydrogen leakage. This communication is aimed towards a prototype optical fiber system designed for the detection of gaseous hydrogen leakage near the conecting flanges of the liquid hydrogen pipes on the test bench of the engine Vulcain of the rocket ARIANE V. Depending on the configuration, the prototype sensor provides a two-level alarm signal and the detection of gaseous hydrogen leakage is possible for concentrations lower than the lower explosive limit in air (between 0.1 and 4%) with alarm response times lower than 10 seconds in a wide range of temperatures between -35°C and 300°C. The sensing principle based on palladium-hydrogen interaction is presented as well as the detection system composed of an optical fiber probe and an optoelectronic device.

  13. Atomic Oxygen Effects on Seal Leakage

    NASA Technical Reports Server (NTRS)

    Christensen, John R.; Underwood, Steve D.; Kamenetzky, Rachel R.; Vaughn, Jason A.

    1998-01-01

    Common Berthing Mechanism (CBM) provides the structural interface between separate International Space Station (ISS) elements, such as the Laboratory and Node modules. The CBM consists of an active and a passive half that join together with structural bolts. The seal at this interface is the CBM-to-CBM molded seal. The CBM-to-CBM interface is assembled on orbit, thus the seals can be exposed to the space environment for up to 65 hours. Atomic Oxygen/Vacuum Ultraviolet radiation (AO/VUV) in space is a potential hazard to the seals. Testing was conducted to determine the effect on leakage of the CBM-to-CBM seal material exposed to AO/VUV. The sealing materials were S383 silicone and V835 fluorocarbon material. Control samples, which were not exposed to the AO/VUV environment, were used to ensure that if any changes in leakage occurred, they could be attributed to the AO/VUV exposure. After exposure to the AO/VUV environment the leakage increase was dramatic for the fluorocarbon. This testing was a major contributing factor in selecting silicone as the CBM-to-CBM seal material.

  14. An improved suppression method of the transverse-electromagnetic mode leakage with two reflectors in the triaxial klystron amplifier

    SciTech Connect

    Qi, Zumin; Zhang, Jun; Zhong, Huihuang; Zhang, Qiang; Zhu, Danni

    2014-07-15

    Suppression of the transverse-electromagnetic (TEM) mode leakage is crucial in the design of a triaxial klystron amplifier with high gain, because a small microwave leakage from the buncher or the output cavity could overwhelm the input signal with low power. In this paper, a specially designed reflector is proposed to suppress the TEM mode leakage, whose axial electric field is approximately zero at the beam radial position. Theoretical analysis indicates that the reflector introduces little influence on the normal modulation of the beam while keeping a high reflection coefficient. By using two such reflectors with different eigen frequencies located in front of the buncher cavity and the output cavity, respectively, an improved triaxial klystron amplifier is presented. The simulation results show that the reflectors substantially decrease the TEM mode leakage power and achieve very good isolation among the cavities. The improved triaxial klystron amplifier can operate normally with 10's kW microwave injection without self-oscillations.

  15. An improved suppression method of the transverse-electromagnetic mode leakage with two reflectors in the triaxial klystron amplifier

    NASA Astrophysics Data System (ADS)

    Qi, Zumin; Zhang, Jun; Zhong, Huihuang; Zhang, Qiang; Zhu, Danni

    2014-07-01

    Suppression of the transverse-electromagnetic (TEM) mode leakage is crucial in the design of a triaxial klystron amplifier with high gain, because a small microwave leakage from the buncher or the output cavity could overwhelm the input signal with low power. In this paper, a specially designed reflector is proposed to suppress the TEM mode leakage, whose axial electric field is approximately zero at the beam radial position. Theoretical analysis indicates that the reflector introduces little influence on the normal modulation of the beam while keeping a high reflection coefficient. By using two such reflectors with different eigen frequencies located in front of the buncher cavity and the output cavity, respectively, an improved triaxial klystron amplifier is presented. The simulation results show that the reflectors substantially decrease the TEM mode leakage power and achieve very good isolation among the cavities. The improved triaxial klystron amplifier can operate normally with 10's kW microwave injection without self-oscillations.

  16. Aeronautical engineering, a special bibliography, September 1971 (supplement 10)

    NASA Technical Reports Server (NTRS)

    1971-01-01

    This supplement to Aeronautical Engineering-A Special Bibliography (NASA SP-7037) lists 413 reports, journal articles, and other documents originally announced in September 1971 in Scientific and Technical Aerospace Reports (STAR) or in International Aerospace Abstracts (IAA). The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the bibliography consists of a standard bibliographic citation accompanied by an abstract. The listing of the entries is arranged in two major sections, IAA Entries and STAR Entries in that order. The citations and abstracts are reproduced exactly as they appeared originally in IAA or STAR, including the original accession numbers from the respective announcement journals.

  17. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 411

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-2000-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes- subject and author are included after the abstract section.

  18. NASA's Role in Aeronautics: A Workshop. Volume 2: Military aviation

    NASA Technical Reports Server (NTRS)

    1981-01-01

    While the National Aeronautics and Space Act of 1958 makes DOD primarily responsible for military aeronautics, it stipulates a role for NASA in providing direct and indirect support for national defense. The existing role of NASA in support of military aeronautics is working well and is well coordinated. The role needs only to be kept effective and then improved by increasing its responsiveness to changing military requirements and by the selective application of additional people. Funding resources should also be made available to NASA for research. Specific roles that NASA could or should play were examined. It was determined that the most important areas for this support are in basic research, generic technology evolution, and facility support in the fields of aerodynamics, structures and materials, and propulsion.

  19. The Aeronautics Education, Research, and Industry Alliance (AERIAL) 2002 Report

    NASA Technical Reports Server (NTRS)

    Bowen, Brent D.; Box, Richard C.; Fink, Mary; Gogos, George; Lehrer, Henry R.; Narayanan, Ram M.; Nickerson, Jocelyn S.; Tarry, Scott E.; Vlasek, Karisa D.; O'Neil, Patrick D.

    2002-01-01

    The NASA Nebraska Space Grant Consortium (NSGC) & EPSCoR programs at the University of Nebraska at Omaha are involved in a variety of innovative research activities. Such research is supported through the Aeronautics Education, Research, and Industry Alliance (AERIAL) and collaborative seed funds. AERIAL is a comprehensive, multi-faceted, five year NASA EPSCoR initiative that contributes substantially to the strategic research and technology priorities of NASA while intensifying Nebraska s rapidly growing aeronautics research and development endeavors. AERIAL includes three major collaborative research teams (CRTs) whose nexus is a common focus in aeronautics research. Each CRT - Small Aircraft Transportation System (SATS), Airborne Remote Sensing for Agricultural Research and Commercialization Applications (ARS), and Numerical Simulation of the Combustion of Fuel Droplets: Finite Rate Kinetics and Flame Zone Grid Adaptation (CEFD) -has a distinct research agenda. This program provides the template for funding of new and innovative research that emphasizes aerospace technology.

  20. Application of the Iridium Satellite System to Aeronautical Communications

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Meza, Mike; Gupta, Om

    2008-01-01

    The next generation air transportation system will require greater air-ground communications capacity to accommodate more air traffic with increased safety and efficiency. Communications will remain primarily terrestrially based, but satellite communications will have an increased role. Inmarsat s aeronautical services have been approved and are in use for aeronautical safety communications provided by geostationary satellites. More recently the approval process for the Iridium low earth orbit constellation is nearing completion. The current Iridium system will be able to provide basic air traffic services communications suitable for oceanic, remote and polar regions. The planned second generation of the Iridium system, called Iridium NEXT, will provide enhanced capabilities and enable a greater role in the future of aeronautical communications. This paper will review the potential role of satellite communications in the future of air transportation, the Iridium approval process and relevant system testing, and the potential role of Iridium NEXT.

  1. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplment 394

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-1999-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes-subject and author are included after the abstract section.

  2. Aeronautics Technology Possibilities for 2000: Report of a workshop

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The potential of aeronautical research and technology (R&T) development, which could provide the basis for facility planning and long range guidance of R&T programs and could establish justification for support of aeronautical research and technology was studied. The projections served specific purposes: (1) to provide a base for research and future facilities needed to support the projected technologies, and development advanced vehicles; (2) to provide insight on the possible state of the art in aeronautical technology by the year 2000 for civil and military planners of air vehicles and systems. Topics discussed include: aerodynamics; propulsion; structures; materials; guidance, navigation and control; computer and information technology; human factors; and systems integration.

  3. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 408

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This supplemental issue of Aeronautical Engineering, a Continuing Bibliography with Indexes (NASA/SP#1999-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes#subject and author are included after the abstract section.

  4. Aeronautical Engineering: A Continuing Bibliography With Indexes. Supplement 407

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-1999-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes-subject and author are included after the abstract section.

  5. Aeronautical Engineering: A Continuing Bibliography with Indexes. Supplement 415

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This supplemental issue of Aeronautical Engineering, A Continuing Bibliography with Indexes (NASA/SP-2000-7037) lists reports, articles, and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes-subject and author are included after the abstract section.

  6. Choice of FDMA/SCPC access technique for aeronautical satellite voice system

    NASA Technical Reports Server (NTRS)

    Smith, G. K.

    1989-01-01

    A worldwide aeronautical mobile satellite system is about to become operational. The system architecture and access methods have been debated extensively, resulting in the selection of Time Division Multiplexing/Time Division Multiple Access (TDM/TDMA) access for packet data, and Single Channel Per Carrier (SCPC) for voice. These have become standards for airline use, and also satisfy the known requirements of ICAO for safety related communications. Voice communications are expected to absorb a high proportion of satellite bandwidth and power in the future. Here, it is explained why INMARSAT selected Frequency Division Multiple Access/SCPC satellite access for this application.

  7. Rotordynamic and leakage characteristics of a 4-stage brush seal

    NASA Astrophysics Data System (ADS)

    Conner, K. J.; Childs, D. W.

    1992-12-01

    Experimental results are presented for the direct and cross-coupled stiffness and damping coefficients as well as the leakage performance for a 4-stage brush seal. Variable test parameters include the inlet pressure, pressure ratio, shaft speed, fluid prerotation, and seal spacing. Direct damping is shown to increase with running speed; otherwise, the rotordynamic coefficients are relatively insensitive to changes in the test parameters. Cross-coupled stiffness is generally unchanged by increasing the inlet tangential velocity to the seals, suggesting that the brush seal is not affected by inlet swirl. Direct stiffness is shown to increase with frequency; however, the magnitudes of direct stiffness are always positive. Cross-coupled stiffness increases slightly with frequency; yet not as drastically as direct stiffness. Comparisons of test results for the 4-stage brush seal with an 8-cavity labyrinth showed superior rotordynamics performance for the brush seal; viz., large values for direct stiffness and lower values for the (destabilizing) cross-coupled stiffness coefficient. The damping for brush seals is smaller, but comparable to labyrinth seals. The whirl-frequency ratio is always smaller for the brush seal.

  8. A Digital Library for the National Advisory Committee for Aeronautics

    NASA Technical Reports Server (NTRS)

    Nelson, Michael L.

    1999-01-01

    We describe the digital library (DL) for the National Advisory Committee for Aeronautics (NACA), the NACA Technical Report Server (NACATRS). The predecessor organization for the National Aeronautics and Space Administration (NASA), NACA existed from 1915 until 1958. The primary manifestation of NACA's research was the NACA report series. We describe the process of converting this collection of reports to digital format and making it available on the World Wide Web (WWW) and is a node in the NASA Technical Report Server (NTRS). We describe the current state of the project, the resulting DL technology developed from the project, and the future plans for NACATRS.

  9. The application of artificial intelligence technology to aeronautical system design

    NASA Technical Reports Server (NTRS)

    Bouchard, E. E.; Kidwell, G. H.; Rogan, J. E.

    1988-01-01

    This paper describes the automation of one class of aeronautical design activity using artificial intelligence and advanced software techniques. Its purpose is to suggest concepts, terminology, and approaches that may be useful in enhancing design automation. By understanding the basic concepts and tasks in design, and the technologies that are available, it will be possible to produce, in the future, systems whose capabilities far exceed those of today's methods. Some of the tasks that will be discussed have already been automated and are in production use, resulting in significant productivity benefits. The concepts and techniques discussed are applicable to all design activity, though aeronautical applications are specifically presented.

  10. Aeronautical Engineering: A Continuing Bibliography With Indexes. Supplement 414

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This report lists reports, articles and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes-subject and author are included after the abstract section.

  11. Astronautics and Aeronautics: A Chronology, 2001-2005

    NASA Technical Reports Server (NTRS)

    Ivey, William Noel; Lewis, Marieke

    2010-01-01

    This report is a chronological compilation of narrative summaries of news reports and government documents highlighting significant events and developments in U.S. and foreign aeronautics and astronautics. It covers the years 2001 through 2005. These summaries provide a day-by-day recounting of major activities, such as administrative developments, awards, launches, scientific discoveries, corporate and government research results, and other events in countries with aeronautics and astronautics programs. Researchers used the archives and files housed in the NASA History Division, as well as reports and databases on the NASA Web site.

  12. Astronautics and Aeronautics: A Chronology, 1996-2000

    NASA Technical Reports Server (NTRS)

    Lewis, Marieke; Swanson, Ryan

    2009-01-01

    This report is a chronological compilation of narrative summaries of news reports and government documents highlighting significant events and developments in United States and foreign aeronautics and astronautics. It covers the years 1996 through 2000. These summaries provide a day-by-day recounting of major activities, such as administrative developments, awards, launches, scientific discoveries, corporate and government research results, and other events in countries with aeronautics and astronautics programs. Researchers used the archives and files housed in the NASA History Division, as well as reports and databases on the NASA Web site.

  13. Aeronautics and space report of the President, 1982 activities

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Achievements of the space program are summerized in the area of communication, Earth resources, environment, space sciences, transportation, aeronautics, and space energy. Space program activities of the various deprtments and agencies of the Federal Government are discussed in relation to the agencies' goals and policies. Records of U.S. and world spacecraft launchings, successful U.S. launches for 1982, U.S. launched applications and scientific satellites and space probes since 1975, U.S. and Soviet manned spaceflights since 1961, data on U.S. space launch vehicles, and budget summaries are provided. The national space policy and the aeronautical research and technology policy statements are included.

  14. Aeronautical technologies for the twenty-first century

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This study gives an overview of the future technologies in aeronautics. This collaborative effort relies upon the input of numerous experts from around the country. Specific issues covered include subsonic transport aircraft, high-speed civil transport aircraft short-haul aircraft, environmental issues, operational issues, aerodynamics, propulsion, materials and structures, avionics and control, and cognitive engineering. The appendices include bibliography, abbreviations and acronyms, and NASA fiscal year 1992 aeronautics funding (table) and participants. The forward states that over the last decade, foreign aircraft manufacturers have made significant inroads into the global aircraft market, to the detriment of U.S. interests. Recommendations are made to counter that trend.

  15. Reserves in Context: Planning for Leakage from Protected Areas

    PubMed Central

    Renwick, Anna R.; Bode, Michael; Venter, Oscar

    2015-01-01

    When protected areas reduce threats within their boundaries, they often displace a portion of these threats into adjacent areas through a process known as ‘leakage’, undermining conservation objectives. Using theoretical models and a case study of terrestrial mammals in Indonesia, we develop the first theoretical explanation of how leakage impacts conservation actions, and highlight conservation strategies that mitigate these impacts. Although leakage is a socio-economic process, we demonstrate that its negative impacts are also affected by the distribution of species, with leakage having larger impacts in landscapes with homogeneous distribution of species richness. Moreover, leakage has a greater negative effect when conservation strategies are implemented opportunistically, even creating the potential for perversely negative consequences from protected area establishment. Leakage thereby increases the relative benefits of systematic conservation planning over opportunism, especially in areas with high leakage and heterogeneously distributed species. Although leakage has the potential to undermine conservation actions, conservation planning can minimize this risk. PMID:26053163

  16. FELERION: a new approach for leakage power reduction

    NASA Astrophysics Data System (ADS)

    R, Anjana; Somkuwar, Ajay

    2014-12-01

    The circuit proposed in this paper simultaneously reduces the sub threshold leakage power and saves the state of art aspect of the logic circuits. Sleep transistors and PMOS-only logic are used to further reduce the leakage power. Sleep transistors are used as the keepers to reduce the sub threshold leakage current providing the low resistance path to the output. PMOS-only logic is used between the pull up and pull down devices to mitigate the leakage power further. Our proposed fast efficient leakage reduction circuit not only reduces the leakage current but also reduces the power dissipation. Power and delay are analyzed at the 32 nm BSIM4 model for a chain of four inverters, NAND, NOR and ISCAS-85 c17 benchmark circuits using DSCH3 and the Microwind tool. The simulation results reveal that our proposed approach mitigates leakage power by 90%-94% as compared to the conventional approach.

  17. A ray tracing study of shock leakage in a model supersonic jet

    NASA Astrophysics Data System (ADS)

    Shariff, Karim; Manning, Ted A.

    2013-07-01

    Recent work has described screech noise from a supersonic jet as being due to leakage of a wave that is otherwise trapped in the jet's interior. In that work, the simplest of many techniques used is ray tracing for a single shear-layer modeled as a row of Stuart vortices. In the present work, a lower row of vortices is added to form a plane jet. Instead of plotting ray paths, a technique of visualization analogous to streaklines is used that better corresponds to instantaneous density fields as observed, for instance, by the Schlieren method. This produces striking images that show leakage of waves at each internal reflection resulting in a row of acoustic sources as envisioned since the 1950s. However, the sources are not isotropic and each has a zone of silence in the downstream direction. Leakage creates a fold in the wave pattern internal to the jet which leads to fine scale features. Reported experiments have also observed fine scale features (described as splitting) in the shock-cell pattern; they may be related to those observed here. Internally reflected rays also undergo a diffusive process as they propagate down the jet. In particular, each successive internal reflection at an unsteady shear-layer scatters rays along a wider range of wave angle and makes them more susceptible to leakage at the next reflection. It also causes more downstream directivity for the more downstream sources. An important result is that as the Mach number Mj is varied, maxima in leakage rate and mean acoustic amplitude occur at (near) resonances between the Mach-wave and shear-layer periods. Maxima in sound pressure level versus Mj have also been reported for laboratory round jets. Finally, as the shear-layer thickness is increased, a minimum in the rate of leakage (correlated with a minimum in radiation amplitude) occurs due to the competing effects of increased shear-layer penetration versus reduced eddy passage frequency.

  18. Hydrogeology from 10,000 ft below: lessons learned in applying pulse testing for leakage detection in a carbon sequestration formation

    NASA Astrophysics Data System (ADS)

    Sun, A. Y.; Lu, J.; Hovorka, S. D.; Freifeld, B. M.; Islam, A.

    2015-12-01

    Monitoring techniques capable of deep subsurface detection are desirable for early warning and leakage pathway identification in geologic carbon storage formations. This work investigates the feasibility of a leakage detection technique based on pulse testing, which is a traditional hydrogeological characterization tool. In pulse testing, the monitoring reservoir is stimulated at a fixed frequency and the acquired pressure perturbation signals are analyzed in the frequency domain to detect potential deviations in the reservoir's frequency domain response function. Unlike traditional time-domain analyses, the frequency-domain analysis aims to minimize the interference of reservoir noise by imposing coded injection patterns such that the reservoir responses to injection can be uniquely determined. We have established the theoretical basis of the approach in previous work. Recently, field validation of this pressure-based, leakage detection technique was conducted at a CO2-EOR site located in Mississippi, USA. During the demonstration, two sets of experiments were performed using 90-min and 150-min pulsing periods, for both with and without leak scenarios. Because of the lack of pre-existing leakage pathways, artificial leakage CO2 was simulated by rate-controlled venting from one of the monitoring wells. Our results show that leakage events caused a significant deviation in the amplitude of the frequency response function, indicating that pulse testing may be used as a cost-effective monitoring technique with a strong potential for automation.

  19. 47 CFR 87.279 - Frequencies.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Frequencies. 87.279 Section 87.279... Aeronautical Fixed Stations § 87.279 Frequencies. (a) United States (except Alaska). The applicant must request specific frequencies in accordance with § 2.106 of this chapter. The Commission will determine...

  20. National Aeronautics and Space Administration (NASA) Education 1993-2009

    ERIC Educational Resources Information Center

    Ivie, Christine M.

    2009-01-01

    The National Aeronautics and Space Administration was established in 1958 and began operating a formal education program in 1993. The purpose of this study was to analyze the education program from 1993-2009 by examining strategic plan documents produced by the NASA education office and interviewing NASA education officials who served during that…

  1. Aeronautics Study Takes Off! Glider Design for Beginners

    ERIC Educational Resources Information Center

    Lazaros, Edward J.; Carlson, Katie

    2008-01-01

    Study of aeronautics is an interesting and motivating subject for students and educators alike. The activity described in this article--appropriate for upper elementary or middle school students--provides an excellent introduction to airplane design and the science of aerodynamics. It also gives students good experience applying knowledge from a…

  2. National Aeronautics and Space Administration Scientific and Technical Information Programs.

    ERIC Educational Resources Information Center

    Pinelli, Thomas E., Ed.

    1990-01-01

    Eleven articles discuss informational and educational programs of the National Aeronautics and Space Administration (NASA). Some of the areas discussed include scientific and technical information management, the new Space and Earth Science Information Systems, transfer of technology to other industries, intellectual property issues, and the…

  3. Aeronautics research and technology program and specific objectives

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Aeronautics research and technology program objectives in fluid and thermal physics, materials and structures, controls and guidance, human factors, multidisciplinary activities, computer science and applications, propulsion, rotorcraft, high speed aircraft, subsonic aircraft, and rotorcraft and high speed aircraft systems technology are addressed.

  4. Aeronautical Envineering at Technion - Israel Institute of Technology.

    ERIC Educational Resources Information Center

    Mathieu, Richard D.

    The shortage of engineers in Israel and the role that the Technion - Israel Institute of Technology plays in the education of engineers is discussed. Emphasis is placed on the academic program, research, and related activities in the Department of Aeronautical Engineering. A brief description of the development of the institute and its…

  5. Aeronautical engineering: A special bibliography with indexes, supplement 49

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The bibliography contains 368 abstract citations of reports, journal articles, and other documents concerned with the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. Research and development in aerodynamics, aeronautics, and ground support equipment are also treated. Subject, personal, and contract number indexes are included for ease of access.

  6. Aeronautical Engineering: A cumulative index to the 1980 issue

    NASA Technical Reports Server (NTRS)

    1981-01-01

    This bibliography is a cumulative index to reports, articles, and other documents introduced into the NASA scientific and technical information system. Abstracts for the entries cited appeared in issues 119 through 130 of Aeronautical Engineering: A Continuing Bibliography (NASA SP-7037). Subject, personal author, corporate author, contract number, and report/accession number indexes are provided.

  7. Astronautics and aeronautics, 1972. [a chronology of events

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Important events of the U. S. space program during 1972 are recorded in a chronology which encompasses all NASA, NASA related, and international cooperative efforts in aeronautics and astronautics. Personnel and budget concerns are documented, along with the major developments in aircraft research, manned space flight, and interplanetary exploration.

  8. 77 FR 71089 - Pilot Loading of Aeronautical Database Updates

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-29

    ... FAA issued regulations (61 FR 19498) categorizing pilot-performed updates of navigation databases as... regulations in the NPRM (76 FR 64859, October 19, 2011), by removing the task of updating databases used in... Federal Aviation Administration 14 CFR Part 43 RIN 2120-AJ91 Pilot Loading of Aeronautical...

  9. Challenges in aeronautical research for the 1990's

    NASA Technical Reports Server (NTRS)

    Holmes, Bruce

    1991-01-01

    Three areas of the specific NASA aeronautical research are discussed: (1) advanced subsonic transport airplanes; (2) next generation high speed civil transport aircraft (SST's); and (3) next century hypersonic vehicles. The research planning reflects an awareness of and sensitivity to modern, stringent environmental constraints, changing marketplace demands, and advanced technology driven opportunities. The technical foundations of those future systems are described.

  10. Aeronautical Engineering: A continuing bibliography with indexes, supplement 185

    NASA Technical Reports Server (NTRS)

    1985-01-01

    This bibliography lists 462 reports, articles and other documents introduced into the NASA scientific and technical information system in February 1985. Aerodynamics, aeronautical engineering, aircraft design, aircraft stability and control, geophysics, social sciences, and space sciences are some of the areas covered.

  11. The role of computational fluid dynamics in aeronautical engineering

    NASA Astrophysics Data System (ADS)

    Kishimoto, Takuji; Uchida, Takashi

    1988-12-01

    Numerical analyses by solving Euler/Navier-Stokes Equations has been used in practical aeronautical engineerings. Here, the results of two dimensional Navier-Stokes analyses of a multiple slotted flap, and a three dimensional wing design problem using Euler analyses are shown.

  12. FY 1978 aeronautics and space technology program summary

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Highlights of the aeronautics program include research on aircraft energy efficiency, supersonic cruise aircraft, vertical takeoff and landing aircraft, short haul/short takeoff and landing aircraft, and general aviation aircraft. The space technology program includes work on space structures, propulsion systems, power systems, materials, and electronics.

  13. Vortex-Lattice Utilization. [in aeronautical engineering and aircraft design

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The many novel, innovative, and unique implementations and applications of the vortex-lattice method to aerodynamic design and analysis which have been performed by Industry, Government, and Universities were presented. Although this analytical tool is not new, it continues to be utilized and refined in the aeronautical community.

  14. A Case Study of Peer Learning in Higher Aeronautical Education

    ERIC Educational Resources Information Center

    Borglund, Dan

    2007-01-01

    In order to improve student learning in an advanced course in aeronautics, lectures are replaced with more student-centred sessions based on peer learning. The course is organised in student teams, with the main task of delivering lecture requests for full class discussions. For the same reason, the written theory exam is replaced by a peer review…

  15. Aeronautical mobile satellite service: Air traffic control applications

    NASA Technical Reports Server (NTRS)

    Sim, Dave

    1990-01-01

    Canada's history both in aviation and in satellite communications development spans several decades. The introduction of aeronautical mobile satellite communications will serve our requirements for airspace management in areas not served by line-of-sight radio and radar facilities. The ensuing improvements in air safety and operating efficiency are eagerly awaited by the aviation community.

  16. Aeronautical engineering: A continuing bibliography with indexes (supplement 316)

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This bibliography lists 413 reports, articles, and other documents introduced into the NASA scientific and technical information system in April 1995. Subject coverage includes: aeronautics; mathematical and computer sciences; chemistry and material sciences; geosciences; design, construction and testing of aircraft and aircraft engines; aircraft components, equipment, and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics.

  17. Quality Program Provisions for Aeronautical and Space System Contractors

    NASA Technical Reports Server (NTRS)

    1969-01-01

    This publication sets forth quality program requirements for NASA aeronautical and space programs, systems, subsystems, and related services. These requirements provide for the effective operation of a quality program which ensures that quality criteria and requirements are recognized, definitized, and performed satisfactorily.

  18. EVA Suit Microbial Leakage Investigation Project

    NASA Technical Reports Server (NTRS)

    Falker, Jay; Baker, Christopher; Clayton, Ronald; Rucker, Michelle

    2016-01-01

    The objective of this project is to collect microbial samples from various EVA suits to determine how much microbial contamination is typically released during simulated planetary exploration activities. Data will be released to the planetary protection and science communities, and advanced EVA system designers. In the best case scenario, we will discover that very little microbial contamination leaks from our current or prototype suit designs, in the worst case scenario, we will identify leak paths, learn more about what affects leakage--and we'll have a new, flight-certified swab tool for our EVA toolbox.

  19. SETI via Leakage from Light Sails in Exoplanetary Systems

    NASA Astrophysics Data System (ADS)

    Guillochon, James; Loeb, Abraham

    2015-10-01

    The primary challenge of rocket propulsion is the burden of needing to accelerate the spacecraft’s own fuel, resulting in only a logarithmic gain in maximum speed as propellant is added to the spacecraft. Light sails offer an attractive alternative in which fuel is not carried by the spacecraft, with acceleration being provided by an external source of light. By artificially illuminating the spacecraft with beamed radiation, speeds are only limited by the area of the sail, heat resistance of its material, and power use of the accelerating apparatus. In this paper, we show that leakage from a light sail propulsion apparatus in operation around a solar system analogue would be detectable. To demonstrate this, we model the launch and arrival of a microwave beam-driven light sail constructed for transit between planets in orbit around a single star, and find an optimal beam frequency on the order of tens of GHz. Leakage from these beams yields transients with flux densities of Jy and durations of tens of seconds at 100 pc. Because most travel within a planetary system would be conducted between the habitable worlds within that system, multiply transiting exoplanetary systems offer the greatest chance of detection, especially when the planets are in projected conjunction as viewed from Earth. If interplanetary travel via beam-driven light sails is commonly employed in our galaxy, this activity could be revealed by radio follow-up of nearby transiting exoplanetary systems. The expected signal properties define a new strategy in the search for extraterrestrial intelligence (SETI).

  20. Predicting Envelope Leakage in Attached Dwellings (Fact Sheet)

    SciTech Connect

    Not Available

    2013-11-01

    The most common method of measuring air leakage is to perform single (or solo) blower door pressurization and/or depressurization test. In detached housing, the single blower door test measures leakage to the outside. In attached housing, however, this "solo" test method measures both air leakage to the outside and air leakage between adjacent units through common surfaces. Although minimizing leakage to neighboring units is highly recommended to avoid indoor air quality issues between units, reduce pressure differentials between units, and control stack effect, the energy benefits of air sealing can be significantly overpredicted if the solo air leakage number is used in the energy analysis. Guarded blower door testing is more appropriate for isolating and measuring leakage to the outside in attached housing. This method uses multiple blower doors to depressurize adjacent spaces to the same level as the unit being tested. Maintaining a neutral pressure across common walls, ceilings, and floors acts as a "guard" against air leakage between units. The resulting measured air leakage in the test unit is only air leakage to the outside. Although preferred for assessing energy impacts, the challenges of performing guarded testing can be daunting.

  1. Geologic Carbon Sequestration: Leakage Potential and Policy Implications

    NASA Astrophysics Data System (ADS)

    Bielicki, J. M.; Peters, C. A.; Fitts, J. P.; Wilson, E. J.

    2014-12-01

    The geologic reservoirs that could be used for long-term sequestration of carbon dioxide (CO2) may have natural or manmade pathways that allow injected CO2, or the brine it displaces, to leak into overlying formations. Using a basin-scale leakage estimation model, we investigated the geophysical parameters that govern this leakage, and the resulting accumulations of leaked fluids in overlying formations. The results are discussed in the context of two polices aimed at governing long-term sequestration and protecting groundwater: the U.S. DOE guideline for storage permanence and the U.S. EPA UIC Program Class VI Rule. For a case study of CO2 injection into the Mt. Simon sandstone in the Michigan sedimentary basin, we showed that (1) the U.S. DOE guideline would allow for more leakage from larger injection projects than for smaller ones; (2) leakage amounts are determined mostly by well leakage permeability rather than by variation in formation permeabilities; (3) numerous leaking wells with anomalously high leakage permeabilities are necessary in order to achieve substantial leakage rates; (4) leakage can reach potable groundwater but intervening stratigraphic traps reduce the amount to be multiple orders of magnitude less than the leakage out of the reservoir, and (5) this leakage can reduce the Area of Review that is defined by the U.S. EPA as the area within which leakage can threaten groundwater. In summary, leakage that exceeds the U.S. DOE storage permanence goal would occur only under extreme conditions, the amount that reaches shallow potable groundwater may be inconsequential from a pollution standpoint, and leakage may be beneficial. Future federal policies should be harmonized to achieve the dual goals of protecting groundwater while allowing for adaptive management that incorporates uncertainties and imperfections inherent in geologic reservoirs.

  2. Aeronautics: An Educator's Guide with Activities in Science, Mathematics, and Technology Education.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    This educator's guide, developed for students in grades 2-4, discusses the field of aeronautics. It begins with education standards and skill matrices for the classroom activities, a description of the National Aeronautics and Space Administration (NASA) aeronautics mission, and a brief history of aeronautics. Activities are written for the…

  3. 77 FR 47913 - Public Notice for Waiver of Aeronautical Land-Use Assurance; Southern Illinois Airport...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-10

    ... Federal Aviation Administration Public Notice for Waiver of Aeronautical Land-Use Assurance; Southern... to change a portion of airport land from aeronautical use to non-aeronautical use at the Southern... before modifying the land-use assurance that requires the property to be used for an aeronautical...

  4. EM information leakage from display unit and visual inspection for its leakage source

    NASA Astrophysics Data System (ADS)

    Watanabe, Takashi; Sako, Hiroshi

    2013-05-01

    Display unit emits a small amount of electromagnetic wave. Although it is weak enough to prevent interference with human body, information leaks through it. This paper presents an experiment on exploring the leakage source by visually inspecting the screen images reconstructed from captured electromagnetic waves. Additionally, some countermeasures are investigated to avoid the problem.

  5. Apical leakage of four endodontic sealers.

    PubMed

    Pommel, Ludovic; About, Imad; Pashley, David; Camps, Jean

    2003-03-01

    The purpose of this study was to evaluate the sealing properties of four root canal sealers. Forty-eight maxillary central incisors were instrumented with Profile rotary instruments. They were randomly divided into four groups (n = 12) and filled using lateral condensation with one of the four sealers: Sealapex, Pulp Canal Sealer, AH 26, and Ketac-Endo. The apical leakage was measured with a fluid filtration method and expressed as L s(-1) KPa(-1). The teeth filled with Sealapex displayed a higher apical leakage (8.42 +/- 4.2 10(-11) L s(-1) KPa(-1)) than those filled with AH 26 (2.10 +/- 1.39 10(-11) L s(-1) KPa(-1)), Pulp Canal Sealer (0.17 +/- 0.09 10(-11) L s(-1) KPa(-1)) or Ketac-Endo (0.32 +/- 0.24 10(-1) L s(-1) KPa(-1)) (p < 0.01). No statistically significant difference was found among AH 26, Pulp Canal Sealer, and Ketac-Endo. No correlation was found between the sealing efficiency of the four sealers and their adhesive properties recorded in a previous study. PMID:12669883

  6. Comparing Natural Gas Leakage Detection Technologies Using an Open-Source "Virtual Gas Field" Simulator.

    PubMed

    Kemp, Chandler E; Ravikumar, Arvind P; Brandt, Adam R

    2016-04-19

    We present a tool for modeling the performance of methane leak detection and repair programs that can be used to evaluate the effectiveness of detection technologies and proposed mitigation policies. The tool uses a two-state Markov model to simulate the evolution of methane leakage from an artificial natural gas field. Leaks are created stochastically, drawing from the current understanding of the frequency and size distributions at production facilities. Various leak detection and repair programs can be simulated to determine the rate at which each would identify and repair leaks. Integrating the methane leakage over time enables a meaningful comparison between technologies, using both economic and environmental metrics. We simulate four existing or proposed detection technologies: flame ionization detection, manual infrared camera, automated infrared drone, and distributed detectors. Comparing these four technologies, we found that over 80% of simulated leakage could be mitigated with a positive net present value, although the maximum benefit is realized by selectively targeting larger leaks. Our results show that low-cost leak detection programs can rely on high-cost technology, as long as it is applied in a way that allows for rapid detection of large leaks. Any strategy to reduce leakage should require a careful consideration of the differences between low-cost technologies and low-cost programs. PMID:27007771

  7. Summary of Jimsphere wind profiles: Programs, data, comments, part 1. [for use in aeronautical vehicle design and engineering

    NASA Technical Reports Server (NTRS)

    Willett, J. A.

    1979-01-01

    Jimsphere wind profiles are documented for the following ranges and installations: Eastern Test Range, Cape Kennedy, Florida; Western Test Range; Point Mugu, California; White Sands Missile Range, New Mexico; Wallops Island, Virginia; Green River, Utah; and Vandenberg Air Force Base, California. Profile information for 1964-1977 includes data summaries, computer formats, frequency distributions, composite listings, etc., for use in establishing and interpreting natural environment criteria for aeronautical vehicle design and engineering operations.

  8. Optical imaging to map blood-brain barrier leakage

    NASA Astrophysics Data System (ADS)

    Jaffer, Hayder; Adjei, Isaac M.; Labhasetwar, Vinod

    2013-11-01

    Vascular leakage in the brain is a major complication associated with brain injuries and certain pathological conditions due to disruption of the blood-brain barrier (BBB). We have developed an optical imaging method, based on excitation and emission spectra of Evans Blue dye, that is >1000-fold more sensitive than conventional ultraviolet spectrophotometry. We used a rat thromboembolic stroke model to validate the usefulness of our method for vascular leakage. Optical imaging data show that vascular leakage varies in different areas of the post-stroke brain and that administering tissue plasminogen activator causes further leakage. The new method is quantitative, simple to use, requires no tissue processing, and can map the degree of vascular leakage in different brain locations. The high sensitivity of our method could potentially provide new opportunities to study BBB leakage in different pathological conditions and to test the efficacy of various therapeutic strategies to protect the BBB.

  9. Residential Forced Air System Cabinet Leakage and Blower Performance

    SciTech Connect

    Walker, Iain S.; Dickerhoff, Darryl J.; Delp, William W.

    2010-03-01

    This project evaluated the air leakage and electric power consumption of Residential HVAC components, with a particular focus on air leakage of furnace cabinets. Laboratory testing of HVAC components indicated that air leakage can be significant and highly variable from unit to unit ? indicating the need for a standard test method and specifying maximum allowable air leakage in California State energy codes. To further this effort, this project provided technical assistance for the development of a national standard for Residential HVAC equipment air leakage. This standard is being developed by ASHRAE and is called"ASHRAE Standard 193P - Method of test for Determining the Air Leakage Rate of HVAC Equipment". The final part of this project evaluated techniques for measurement of furnace blower power consumption. A draft test procedure for power consumption was developed in collaboration with the Canadian General Standards Board: CSA 823"Performance Standard for air handlers in residential space conditioning systems".

  10. Underwater gas pipeline leakage source localization by distributed fiber-optic sensing based on particle swarm optimization tuning of the support vector machine.

    PubMed

    Huang, Yue; Wang, Qiang; Shi, Lilian; Yang, Qihua

    2016-01-10

    Accurate underwater gas pipeline leak localization requires particular attention due to the sensitivity of environmental conditions. Experiments were performed to analyze the localization performance of a distributed optical fiber sensing system based on the hybrid Sagnac and Mach-Zehnder interferometer. The traditional null frequency location method does not easily allow accurate location of the leakage points. To improve the positioning accuracy, the particle swarm optimization algorithm (PSO) tuning of the support vector machine (SVM) was used to predict the leakage points based on gathered leakage data. The PSO is able to optimize the SVM parameters. For the 10 km range chosen, the results show the PSO-SVM average absolute error of the leakage points predicted is 66 m. The prediction accuracy of leakage points is 98.25% by PSO tuning of the SVM processing. For 20 leakage test data points, the average absolute error of leakage point location is 124.8 m. The leakage position predicted by the PSO algorithm after optimization of the parameters is more accurate. PMID:26835758

  11. The Effects of Safety Information on Aeronautical Decision Making

    NASA Technical Reports Server (NTRS)

    Lee, Jang R.; Fanjoy, Richard O.; Dillman, Brian G.

    2005-01-01

    The importance of aeronautical decision making (ADM) has been considered one of the most critical issues of flight education for future professional pilots. Researchers have suggested that a safety information system based on information from incidents and near misses is an important tool to improve the intelligence and readiness of pilots. This paper describes a study that examines the effect of safety information on aeronautical decision making for students in a collegiate flight program. Data was collected from study participants who were exposed to periodic information about local aircraft malfunctions. Participants were then evaluated using a flight simulator profile and a pen and pencil test of situational judgment. Findings suggest that regular access to the described safety information program significantly improves decision making of student pilots.

  12. NASA's Role in Aeronautics: A Workshop. Volume 4: General aviation

    NASA Technical Reports Server (NTRS)

    1981-01-01

    A substantially improved flow of new technology is imperative if the general aviation industry is to maintain a strong world position. Although NASA is the most eminently suited entity available to carry out the necessary research and technology development effort because of its facilities, expertise, and endorsement by the aircraft industry, less than 3% of its aeronautical R&T budget is devoted to general aviation aeronautics. It is recommended that (1) a technology program, particularly one that focuses on improving fuel efficienty and safety, be aggressively pursued by NASA; (2) NASA be assigned the role of leading basic research technology effort in general aviation up through technology demonstration; (3) a strategic plan be developed by NASA, in cooperation with the industry, and implemented in time for the 1982 budget cycle; and (4) a NASA R&T budget be allocated for general aviation adequate to support the proposed plan.

  13. National Aeronautics and Space Administration FY 2001 Accountability Report

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The National Aeronautics and Space Administration (NASA) is an independent Agency established to plan and manage the future of the Nation's civil aeronautics and space program. This Accountability Report covers Federal Fiscal Year (FY) 2001 (October 1, 2000, through September 30, 2001), with discussion of some subsequent events The Report contains an overview addressing the Agency's critical programs and financial performance and includes highlights of performance organized by goals and objectives of the Enterprises and Crosscutting Processes. The Report also summarizes NASA's stewardship over budget and financial resources, including audited financial statements and footnotes. The financial statements reflect an overall position of offices and activities, including assets and liabilities, as well as results of operations, pursuant to requirements of Federal law (31 U.S.C. 3515(b)). The auditor's opinions on NASA's financial statements, reports on internal controls, and compliance with laws and regulations are included in this Report.

  14. Chemical Gas Sensors for Aeronautic and Space Applications 2

    NASA Technical Reports Server (NTRS)

    Hunter, Gary W.; Chen, Liong-Yu; Neudeck, Phil G.; Knight, Dale; Liu, C. C.; Wu, Q. H.; Zhou, H. J.; Makel, Darby; Liu, M.; Rauch, W. A.

    1998-01-01

    Aeronautic and space applications require the development of chemical sensors with capabilities beyond those of commercially available sensors. Areas of interest include launch vehicle safety monitoring, emission monitoring, and fire detection. This paper discusses the needs of aeronautic and space applications and the point-contact sensor technology being developed to address these needs. The development of these sensors is based on progress in two types of technology: 1) Micromachining and microfabrication technology to fabricate miniaturized sensors. 2) The development of high temperature semiconductors, especially silicon carbide. Sensor development for each application involves its own challenges in the fields of materials science and fabrication technology. The number of dual-use commercial applications of this microfabricated gas sensor technology make this area of sensor development a field of significant interest.

  15. Chemical Gas Sensors for Aeronautic and Space Applications 2

    NASA Technical Reports Server (NTRS)

    Hunter, G. W.; Chen, L. Y.; Neudeck, P. G.; Knight, D.; Liu, C. C.; Wu, Q. H.; Zhou, H. J.; Makel, D.; Liu, M.; Rauch, W. A.

    1998-01-01

    Aeronautic and Space applications require the development of chemical sensors with capabilities beyond those of commercially available sensors. Areas of most interest include launch vehicle safety monitoring emission monitoring and fire detection. This paper discusses the needs of aeronautic and space applications and the point-contact sensor technology being developed to address these needs. The development of these sensor is based on progress two types of technology: 1) Micro-machining and micro-fabrication technology to fabricate miniaturized sensors. 2) The development of high temperature semiconductors, especially silicon carbide. Sensor development for each application involves its own challenges in the fields of materials science and fabrication technology. The number of dual-use commercial applications of this micro-fabricated gas sensor technology make this area of sensor development a field of significant interest.

  16. Chemical Gas Sensors for Aeronautic and Space Applications

    NASA Technical Reports Server (NTRS)

    Hunter, Gary W.; Chen, Liang-Yu; Neudeck, Philip G.; Knight, Dak; Liu, Chung-Chiun; Wu, Quing-Hai; Zhou, Huan-Jun

    1997-01-01

    Aeronautic and space applications require the development of chemical sensors with capabilities beyond those of commercially available sensors. Two areas of particular interest are safety monitoring and emission monitoring. In safety monitoring, detection of low concentrations of hydrogen at potentially low temperatures is important while for emission monitoring the detection of nitrogen oxides, hydrogen, hydrocarbons and oxygen is of interest. This paper discusses the needs of aeronautic and space applications and the point-contact sensor technology being developed to address these needs. The development of these sensors is based on progress in two types of technology: (1) Micromachining and microfabrication technology to fabricate miniaturized sensors. (2) The development of high temperature semiconductors, especially silicon carbide. The detection of each type of gas involves its own challenges in the fields of materials science and fabrication technology. The number of dual-use commercial applications of this microfabricated gas sensor technology make this general area of sensor development a field of significant interest.

  17. Chemical Gas Sensors for Aeronautics and Space Applications III

    NASA Technical Reports Server (NTRS)

    Hunter, G. W.; Neudeck, P. G.; Chen, L. Y.; Liu, C. C.; Wu, Q. H.; Sawayda, M. S.; Jin, Z.; Hammond, J.; Makel, D.; Liu, M.; Rauch, W. A.; Hall, G.

    1999-01-01

    Aeronautic and space applications require the development of chemical sensors with capabilities beyond those of commercially available sensors. Areas of interest include launch vehicle safety monitoring, emission monitoring, and fire detection. This paper discusses the needs of aeronautic and space applications and the point-contact sensor technology being developed to address these needs. The development of these sensors is based on progress in two types of technology: 1) Micromachining and microfabrication technology to fabricate miniaturized sensors. 2) The development of high temperature semiconductors, especially silicon carbide. Sensor development for each application involves its own challenges in the fields of materials science and fabrication technology. The number of dual-use commercial applications of this microfabricated gas sensor technology make this area of sensor development a field of significant interest.

  18. National Aeronautics and Space Administration Fiscal Year 2001 Accountability Report

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The National Aeronautics and Space Administration (NASA) is an independent Agency established to plan and manage the future of the Nation's civil aeronautics and space program. This Accountability Report covers Federal Fiscal Year (FY) 2001 (October 1, 2000, through September 30, 2001), with discussion of some subsequent events. The Report contains an overview addressing the Agency's critical programs and financial performance and includes highlights of performance organized by goals and objectives of the Enterprises and Crosscutting Processes. The Report also summarizes NASA's stewardship over budget and financial resources, including audited financial statements and footnotes. The financial statements reflect an overall position of offices and activities, including assets and liabilities, as well as results of operations, pursuant to requirements of Federal law (31 U.S.C. 3515(b)). The auditor's opinions on NASA's financial statements, reports on internal controls, and compliance with laws and regulations are included in this report.

  19. Tribology needs for future space and aeronautical systems

    NASA Technical Reports Server (NTRS)

    Fusaro, Robert L.

    1991-01-01

    Future aeronautical and space missions will push tribology technology beyond its current capability. The objective is to discuss the current state of the art of tribology as it is applied to advanced aircraft and spacecraft. Areas of discussion include materials lubrication mechanisms, factors affecting lubrication, current and future tribological problem areas, potential new lubrication techniques, and perceived technology requirements that need to be met in order to solve these tribology problems.

  20. NASA's Role in Aeronautics: A Workshop. Volume 3: Transport aircraft

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Segments of the spectrum of research and development activities that clearly must be within the purview of NASA in order for U.S. transport aircraft manufacturing and operating industries to succeed and to continue to make important contributions to the nation's wellbeing were examined. National facilities and expertise; basic research, and the evolution of generic and vehicle class technologies were determined to be the areas in which NASA has an essential role in transport aircraft aeronautics.

  1. The Aeronautics Education, Research, and Industry Alliance (AERIAL) 2002 Report

    NASA Technical Reports Server (NTRS)

    Bowen, Brent D.; Fink, Mary M.; Nickerson, Jocelyn S.

    2002-01-01

    This report presents and overview of the Aeronautics Education, Research, and Industry Alliance (AERIAL). It covers the University of Nebraska's areas of research, and its outreach to students at Native American schools as part of AERIAL. The report contains three papers: "Airborne Remote Sensing (ARS) for Agricultural Research and Commercialization Application" (White Paper), "Validated Numerical Models for the Convective Extinction of Fuel Droplets (CEFD)", and "The Small Aircraft Transportation System (SATS): Research Collaborations with the NASA Langley Research Center".

  2. Experimental Investigation of Elastomer Docking Seal Compression Set, Adhesion, and Leakage

    NASA Technical Reports Server (NTRS)

    Daniels, Christopher C.; Oswald, Jay J.; Bastrzyk, Marta B.; Smith, Ian; Dunlap, Patrick H., Jr.; Steinetz, Bruce M.

    2008-01-01

    A universal docking and berthing system is being developed by the National Aeronautics and Space Administration (NASA) to support all future space exploration missions to low-Earth orbit (LEO), to the Moon, and to Mars. An investigation of the compression set of two seals mated in a seal-on-seal configuration and the force required to separate the two seals after periods of mating was conducted. The leakage rates of seals made from two silicone elastomer compounds, S0383-70 and S0899-50, configured in seal-on-seal mating were quantified. The test specimens were sub-scale seals with representative cross-sections and a 12 inch outside diameter. The leakage rate of the seals manufactured from S0899-50 was higher than that of the seals made from S0383-70 by a factor of 1.8. Similarly, the adhesion of the 50 durometer elastomer was significantly higher than that of the 70 durometer compound. However, the compression set values of the S0899-50 material were observed to be significantly lower than those for the S0383-70.

  3. Postoperative Cerebrospinal Fluid Leakage Associated With Total En Bloc Spondylectomy.

    PubMed

    Yokogawa, Noriaki; Murakami, Hideki; Demura, Satoru; Kato, Satoshi; Yoshioka, Katsuhito; Hayashi, Hiroyuki; Ishii, Takayoshi; Igarashi, Takashi; Fang, Xiang; Tsuchiya, Hiroyuki

    2015-07-01

    Cerebrospinal fluid (CSF) leakage is a serious postoperative complication associated with total en bloc spondylectomy. The authors examined the risk factors for CSF leakage after this procedure. A total of 72 patients underwent total en bloc spondylectomy at the authors' institution between May 2010 and April 2013. Postoperative CSF leakage was observed in 17 of the 72 patients (23.6%). The results of univariate analysis suggested that age 54 years or older, preoperative surgical site irradiation, resection of 3 or more vertebral bodies, and dural injury were significant risk factors for postoperative CSF leakage after total en bloc spondylectomy. Multivariate analysis showed that preoperative surgical site irradiation was the only significant risk factor for postoperative CSF leakage (adjusted odds ratio, 5.22; 95% confidence interval, 1.03-26.45, P=.046). The authors also assessed the course of treatment for postoperative CSF leakage in each patient. Of 17 patients with postoperative CSF leakage, 13 recovered without further complications, but 4 required reoperation (2 for wound dehiscence, 1 for surgical site infection, and 1 for severe intracranial hypotension). All 4 patients who required reoperation had a history of surgical site irradiation. Thus, this study suggests that careful consideration should be given to postoperative CSF leakage in patients with a history of surgical site irradiation. These findings may contribute to the management of postoperative CSF leakage associated with total en bloc spondylectomy and supplement the information given to the patient in the process of obtaining informed consent. PMID:26186316

  4. Aeronautical technology 2000: A projection of advanced vehicle concepts

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The Aeronautics and Space Engineering Board (ASEB) of the National Research Council conducted a Workshop on Aeronautical Technology: a Projection to the Year 2000 (Aerotech 2000 Workshop). The panels were asked to project advances in aeronautical technologies that could be available by the year 2000. As the workshop was drawing to a close, it became evident that a more comprehensive investigation of advanced air vehicle concepts than was possible in the limited time available at the workshop would be valuable. Thus, a special panel on vehicle applications was organized. In the course of two meetings, the panel identified and described representative types of aircraft judged possible with the workshop's technology projections. These representative aircraft types include: military aircraft; transport aircraft; rotorcraft; extremely high altitude aircraft; and transatmospheric aircraft. Improvements in performance, efficiency, and operational characteristics possible through the application of the workshop's year 2000 technology projections were discussed. The subgroups also identified the technologies considered essential and enhancing or supporting to achieve the projected aircraft improvements.

  5. From Aeronautics to Space: Lessons in Human Automation

    NASA Technical Reports Server (NTRS)

    Connors, Mary M.; Rosekind, Mark R. (Technical Monitor)

    1996-01-01

    Civilian air flight continues on a growth curve, as more and more people utilize air travel to meet business and personal travel needs: This consumer-driven demand has resulted in the adoption of new methods to increase air system capacity and to make the air transportation system increasingly more efficient. As a consequence, civilian aviation, as an industry, has assumed a leading role in the use of automated systems, and, by implication, in the understanding of how human openers interact with these systems. Aeronautical automation systems serve a variety of roles. These include controlling aircraft and aiding, advising and monitoring numerous functions in the aircraft/airspace system. Experiences in the use of human/automation systems gathered from aviation are, in many cases, generalizable to other industries having similar requirements for human and non-human intelligent system interaction. However, the human/automation lessons learned from aviation have special relevance to the space application, where many of the same operational demands prevail. The application of aeronautical lessons of human-automated interaction to spaceflight is the subject of this paper. The discussion will address: the progress that has been made through aeronautically-based research and experience in understanding human/automation interaction, ways that this understanding can be applied to the needs of space, and the limits of our present understanding of human/automations systems. Suggestions will be offered related to human-automation research generally, and to the particular needs of the space endeavor.

  6. Estimating sewer leakage from continuous tracer experiments.

    PubMed

    Rieckermann, Jörg; Bares, Vojtech; Kracht, Oliver; Braun, Daniel; Gujer, Willi

    2007-05-01

    Direct measurements of sewer leakage with continuous dosing of tracers are often considered too imprecise for practical applications. However, no mathematical framework for data analysis is reported in literature. In this paper, we present an improved experimental design and data analysis procedure together with a comprehensive framework for uncertainty assessment. Test runs in a 700 m-long watertight sewer showed no significant bias and a very high precision of the methodology. The standard error in the results was assessed to 2.6% of the labeled flow with a simplified model. It could be reduced to 1.2% when a dynamic data analysis procedure was applied. The major error contribution was caused by transient transport phenomena, which suggests that careful choosing of the experimental time is more important than the choice of a very specific tracer substance. Although the method is not intended to replace traditional CCTV inspections, it can provide complementary information for rational rehabilitation planning. PMID:17363025

  7. Torque Transmission Device at Zero Leakage

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.; Mullen, R. L.

    2005-01-01

    In a few critical applications, mechanical transmission of power by rotation at low speed is required without leakage at an interface. Herein we examine a device that enables torque to be transmitted across a sealed environmental barrier. The barrier represents the restraint membrane through which the torque is transmitted. The power is transferred through elastic deformation of a circular tube into an elliptical cross-section. Rotation of the principle axis of the ellipse at one end results in a commensurate rotation of an elliptical cross section at the other end of the tube. This transfer requires no rigid body rotation of the tube allowing a membrane to seal one end from the other. Both computational and experimental models of the device are presented.

  8. Fluid leakage near the percolation threshold

    PubMed Central

    Dapp, Wolf B.; Müser, Martin H.

    2016-01-01

    Percolation is a concept widely used in many fields of research and refers to the propagation of substances through porous media (e.g., coffee filtering), or the behaviour of complex networks (e.g., spreading of diseases). Percolation theory asserts that most percolative processes are universal, that is, the emergent powerlaws only depend on the general, statistical features of the macroscopic system, but not on specific details of the random realisation. In contrast, our computer simulations of the leakage through a seal—applying common assumptions of elasticity, contact mechanics, and fluid dynamics—show that the critical behaviour (how the flow ceases near the sealing point) solely depends on the microscopic details of the last constriction. It appears fundamentally impossible to accurately predict from statistical properties of the surfaces alone how strongly we have to tighten a water tap to make it stop dripping and also how it starts dripping once we loosen it again. PMID:26839261

  9. Fluid leakage near the percolation threshold

    NASA Astrophysics Data System (ADS)

    Dapp, Wolf B.; Müser, Martin H.

    2016-02-01

    Percolation is a concept widely used in many fields of research and refers to the propagation of substances through porous media (e.g., coffee filtering), or the behaviour of complex networks (e.g., spreading of diseases). Percolation theory asserts that most percolative processes are universal, that is, the emergent powerlaws only depend on the general, statistical features of the macroscopic system, but not on specific details of the random realisation. In contrast, our computer simulations of the leakage through a seal—applying common assumptions of elasticity, contact mechanics, and fluid dynamics—show that the critical behaviour (how the flow ceases near the sealing point) solely depends on the microscopic details of the last constriction. It appears fundamentally impossible to accurately predict from statistical properties of the surfaces alone how strongly we have to tighten a water tap to make it stop dripping and also how it starts dripping once we loosen it again.

  10. Information Leakage Analysis by Abstract Interpretation

    NASA Astrophysics Data System (ADS)

    Zanioli, Matteo; Cortesi, Agostino

    Protecting the confidentiality of information stored in a computer system or transmitted over a public network is a relevant problem in computer security. The approach of information flow analysis involves performing a static analysis of the program with the aim of proving that there will not be leaks of sensitive information. In this paper we propose a new domain that combines variable dependency analysis, based on propositional formulas, and variables' value analysis, based on polyhedra. The resulting analysis is strictly more accurate than the state of the art abstract interpretation based analyses for information leakage detection. Its modular construction allows to deal with the tradeoff between efficiency and accuracy by tuning the granularity of the abstraction and the complexity of the abstract operators.

  11. Fluid leakage near the percolation threshold.

    PubMed

    Dapp, Wolf B; Müser, Martin H

    2016-01-01

    Percolation is a concept widely used in many fields of research and refers to the propagation of substances through porous media (e.g., coffee filtering), or the behaviour of complex networks (e.g., spreading of diseases). Percolation theory asserts that most percolative processes are universal, that is, the emergent powerlaws only depend on the general, statistical features of the macroscopic system, but not on specific details of the random realisation. In contrast, our computer simulations of the leakage through a seal--applying common assumptions of elasticity, contact mechanics, and fluid dynamics--show that the critical behaviour (how the flow ceases near the sealing point) solely depends on the microscopic details of the last constriction. It appears fundamentally impossible to accurately predict from statistical properties of the surfaces alone how strongly we have to tighten a water tap to make it stop dripping and also how it starts dripping once we loosen it again. PMID:26839261

  12. Aeronautics and Aviation Science: Careers and Opportunities Project

    NASA Technical Reports Server (NTRS)

    Texter, P. Cardie

    1998-01-01

    The National Aeronautics and Space Administration funded project, Aeronautics and Aviation Science: Careers and Opportunities has been in operation since July, 1995. This project operated as a collaboration with Massachusetts Corporation for Educational Telecommunications, the Federal Aviation Administration, Bridgewater State College and four targeted "core sites" in the greater Boston area. In its first and second years, a video series on aeronautics and aviation science was developed and broadcast via "live, interactive" satellite feed. Accompanying teacher and student supplementary instructional materials for grades 6-9 were produced and disseminated by the Massachusetts Corporation for Educational Telecommunications (MCET). In the MCET grant application it states that project Take Off! in its initial phase would recruit and train teachers at "core" sites in the greater Boston area, as well as opening participation to other on-line users of MCET's satellite feeds. "Core site" classrooms would become equipped so that teachers and students might become engaged in an interactive format which aimed at not only involving the students during the "live" broadcast of the instructional video series, but which would encourage participation in electronic information gathering and sharing among participants. As a Take Off! project goal, four schools with a higher than average proportion of minority and underrepresented youth were invited to become involved with the project to give these students the opportunity to consider career exploration and development in the field of science aviation and aeronautics. The four sites chosen to participate in this project were: East Boston High School, Dorchester High School, Randolph Junior-Senior High School and Malden High School. In year 3 Dorchester was unable to continue to fully participate and exited out. Danvers was added to the "core site" list in year 3. In consideration of Goals 2000, the National Science Foundation

  13. Aeronautical fuel conservation possibilities for advanced subsonic transports. [application of aeronautical technology for drag and weight reduction

    NASA Technical Reports Server (NTRS)

    Braslow, A. L.; Whitehead, A. H., Jr.

    1973-01-01

    The anticipated growth of air transportation is in danger of being constrained by increased prices and insecure sources of petroleum-based fuel. Fuel-conservation possibilities attainable through the application of advances in aeronautical technology to aircraft design are identified with the intent of stimulating NASA R and T and systems-study activities in the various disciplinary areas. The material includes drag reduction; weight reduction; increased efficiency of main and auxiliary power systems; unconventional air transport of cargo; and operational changes.

  14. Centrifugal acceleration modes for incompressible fluid in the leakage annulus between a shrouded pump impeller and its housing

    NASA Technical Reports Server (NTRS)

    Childs, D. W.

    1991-01-01

    An algorithm is developed for calculating complex eigenvalues and eigenvectors associated with the fluid resonances and is used to analyze the perturbed flow in the leakage path between a shrouded-pump impeller and its housing. The eigenvalues obtained are consistent with the forced-response curves. First- and second-natural-frequency eigensolutions are presented for mode shapes corresponding to lateral excitations, and first-natural-frequency eigensolutions are presented for mode shapes corresponding to axial excitation.

  15. 49 CFR 178.345-13 - Pressure and leakage tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... adjacent cargo tanks empty and at atmospheric pressure. Each closure, except pressure relief devices and... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure and leakage tests. 178.345-13 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.345-13 Pressure and leakage tests. (a)...

  16. 49 CFR 178.345-13 - Pressure and leakage tests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... adjacent cargo tanks empty and at atmospheric pressure. Each closure, except pressure relief devices and... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure and leakage tests. 178.345-13 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.345-13 Pressure and leakage tests. (a)...

  17. 49 CFR 178.345-13 - Pressure and leakage tests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... adjacent cargo tanks empty and at atmospheric pressure. Each closure, except pressure relief devices and... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure and leakage tests. 178.345-13 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.345-13 Pressure and leakage tests. (a)...

  18. 49 CFR 178.345-13 - Pressure and leakage tests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... adjacent cargo tanks empty and at atmospheric pressure. Each closure, except pressure relief devices and... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure and leakage tests. 178.345-13 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.345-13 Pressure and leakage tests. (a)...

  19. A CONCEPTUAL UNDERSTANDING OF LEAKAGE DURING SOIL-GAS SAMPLING

    EPA Science Inventory

    A heuristic model is developed to develop a conceptual understanding of leakage during soil-gas sampling. Leakage is shown to be simply a function of the permeability contrast between the formation and borehole and geometric factors. As the ratio of formation to borehole permea...

  20. 49 CFR 178.348-5 - Pressure and leakage test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure and leakage test. 178.348-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  1. 49 CFR 178.347-5 - Pressure and leakage test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure and leakage test. 178.347-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.347-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  2. 49 CFR 178.347-5 - Pressure and leakage test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure and leakage test. 178.347-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.347-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  3. 49 CFR 178.348-5 - Pressure and leakage test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure and leakage test. 178.348-5 Section 178... PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b)...

  4. 49 CFR 178.346-5 - Pressure and leakage tests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... is equipped with vapor recovery equipment may be leakage tested in accordance with 40 CFR 63.425(e). To satisfy the leakage test requirements of this paragraph, the test specified in 40 CFR 63.425(e)(1) must be conducted using air. The hydrostatic test alternative permitted under Appendix A to 40 CFR...

  5. 49 CFR 178.346-5 - Pressure and leakage tests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... is equipped with vapor recovery equipment may be leakage tested in accordance with 40 CFR 63.425(e). To satisfy the leakage test requirements of this paragraph, the test specified in 40 CFR 63.425(e)(1) must be conducted using air. The hydrostatic test alternative permitted under Appendix A to 40 CFR...

  6. 49 CFR 178.347-5 - Pressure and leakage test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure and leakage test. 178.347-5 Section 178... PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.347-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b)...

  7. 49 CFR 178.347-5 - Pressure and leakage test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure and leakage test. 178.347-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.347-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  8. 49 CFR 178.346-5 - Pressure and leakage tests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... is equipped with vapor recovery equipment may be leakage tested in accordance with 40 CFR 63.425(e). To satisfy the leakage test requirements of this paragraph, the test specified in 40 CFR 63.425(e)(1) must be conducted using air. The hydrostatic test alternative permitted under Appendix A to 40 CFR...

  9. 49 CFR 178.348-5 - Pressure and leakage test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure and leakage test. 178.348-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  10. 49 CFR 178.346-5 - Pressure and leakage tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... is equipped with vapor recovery equipment may be leakage tested in accordance with 40 CFR 63.425(e). To satisfy the leakage test requirements of this paragraph, the test specified in 40 CFR 63.425(e)(1) must be conducted using air. The hydrostatic test alternative permitted under Appendix A to 40 CFR...

  11. 49 CFR 178.348-5 - Pressure and leakage test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure and leakage test. 178.348-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  12. 49 CFR 178.348-5 - Pressure and leakage test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure and leakage test. 178.348-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  13. 49 CFR 178.347-5 - Pressure and leakage test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure and leakage test. 178.347-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.347-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  14. 40 CFR 264.252 - Action leakage rate.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Action leakage rate. 264.252 Section 264.252 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Waste Piles § 264.252 Action leakage rate. (a)...

  15. 40 CFR 264.222 - Action leakage rate.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Action leakage rate. 264.222 Section 264.222 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Surface Impoundments § 264.222 Action leakage...

  16. 40 CFR 265.222 - Action leakage rate.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Surface Impoundments § 265.222 Action leakage rate. (a) The owner or operator of surface...) The Regional Administrator shall approve an action leakage rate for surface impoundment units...

  17. 40 CFR 265.222 - Action leakage rate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Surface Impoundments § 265.222 Action leakage rate. (a) The owner or operator of surface...) The Regional Administrator shall approve an action leakage rate for surface impoundment units...

  18. 42 CFR 84.158 - Exhalation valve leakage test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Exhalation valve leakage test. 84.158 Section 84... Respirators § 84.158 Exhalation valve leakage test. (a) Dry exhalation valves and valve seats will be... between the valve and valve seat shall not exceed 30 milliliters per minute....

  19. 42 CFR 84.158 - Exhalation valve leakage test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Exhalation valve leakage test. 84.158 Section 84... Respirators § 84.158 Exhalation valve leakage test. (a) Dry exhalation valves and valve seats will be... between the valve and valve seat shall not exceed 30 milliliters per minute....

  20. 42 CFR 84.158 - Exhalation valve leakage test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Exhalation valve leakage test. 84.158 Section 84... Respirators § 84.158 Exhalation valve leakage test. (a) Dry exhalation valves and valve seats will be... between the valve and valve seat shall not exceed 30 milliliters per minute....