WorldWideScience

Sample records for subject terms aircraft

  1. Prediction of UHPFRC panels thickness subjected to aircraft engine impact

    OpenAIRE

    Thai, Duc-Kien; Kim, Seung-Eock

    2016-01-01

    In the practical design of nuclear building structures subjected to an aircraft crash, the structures are required to prevent scabbing and perforation. NEI 07-13 provided the formulas to predict the minimum reinforced concrete (RC) wall thickness to prevent the local damage caused by aircraft engine impact. However, these formulas may not be suitable for predicting the thickness of the ultra-high performance fiber reinforced concrete (UHPFRC) wall. In this study, the local damage of a UHPFRC ...

  2. Trajectory Optimization of Electric Aircraft Subject to Subsystem Thermal Constraints

    Science.gov (United States)

    Falck, Robert D.; Chin, Jeffrey C.; Schnulo, Sydney L.; Burt, Jonathan M.; Gray, Justin S.

    2017-01-01

    Electric aircraft pose a unique design challenge in that they lack a simple way to reject waste heat from the power train. While conventional aircraft reject most of their excess heat in the exhaust stream, for electric aircraft this is not an option. To examine the implications of this challenge on electric aircraft design and performance, we developed a model of the electric subsystems for the NASA X-57 electric testbed aircraft. We then coupled this model with a model of simple 2D aircraft dynamics and used a Legendre-Gauss-Lobatto collocation optimal control approach to find optimal trajectories for the aircraft with and without thermal constraints. The results show that the X-57 heat rejection systems are well designed for maximum-range and maximum-efficiency flight, without the need to deviate from an optimal trajectory. Stressing the thermal constraints by reducing the cooling capacity or requiring faster flight has a minimal impact on performance, as the trajectory optimization technique is able to find flight paths which honor the thermal constraints with relatively minor deviations from the nominal optimal trajectory.

  3. Nuclear containment structure subjected to commercial and fighter aircraft crash

    Energy Technology Data Exchange (ETDEWEB)

    Sadique, M.R., E-mail: rehan.sadique@gmail.com; Iqbal, M.A., E-mail: iqbalfce@iitr.ernet.in; Bhargava, P., E-mail: bhpdpfce@iitr.ernet.in

    2013-07-15

    Highlights: • Nuclear containment response has been studied against aircraft crash. • Concrete damaged plasticity and Johnson–Cook elasto-viscoplastic models were employed. • Boeing 747-400 and Boeing 767-400 aircrafts caused global failure of containment. • Airbus A320 and Boeing 707-320 aircrafts caused local damage. • Tension damage of concrete was found more prominent compared to compression damage. -- Abstract: The response of a boiling water reactor (BWR) nuclear containment vessel has been studied against commercial and fighter aircraft crash using a nonlinear finite element code ABAQUS. The aircrafts employed were Boeing 747-400, Boeing 767-400, Airbus A-320, Boeing 707-320 and Phantom F4. The containment was modeled as a three-dimensional deformable reinforced concrete structure while the loading of aircraft was assigned using the respective reaction–time curve. The location of strike was considered near the junction of dome and cylinder, and the angle of incidence, normal to the containment surface. The material behavior of the concrete was incorporated using the damaged plasticity model while that of the reinforcement, the Johnson–Cook elasto-viscoplastic model. The containment could not sustain the impact of Boeing 747-400 and Boeing 767-400 aircrafts and suffered rupture of concrete around the impact region leading to global failure. On the other hand, the maximum local deformation at the point of impact was found to be 0.998 m, 0.099 m, 0.092 m, 0.089 m, and 0.074 m against Boeing 747-400, Phantom F4, Boeing 767, Boeing 707-320 and Airbus A-320 aircrafts respectively. The results of the present study were compared with those of the previous analytical and numerical investigations with respect to the maximum deformation and overall behavior of the containment.

  4. Safety assessment of a nuclear power plant building subjected to an aircraft crash

    Energy Technology Data Exchange (ETDEWEB)

    Thai, Duc-Kien; Kim, Seung-Eock, E-mail: sekim@sejong.ac.kr

    2015-11-15

    Highlights: • Numerical analysis of a nuclear auxiliary building under aircraft crash is conducted. • The analysis result of impact force is verified using the Riera function. • The safety assessment is performed with regard to different impact scenarios. • Discussions and conclusions on safety of the nuclear building are presented. - Abstract: This paper presents a safety assessment of a nuclear building subjected to an aircraft crash using numerical analysis. For impact simulation, the reinforced concrete (RC) Primary Auxiliary Building (PAB) of the Korea Standard Nuclear Power Plant (KSNP) is fully modeled and an aircraft model of a Boeing 767-400 is used. The Riera function is used to verify the analysis result of impact force–time history. The IRIS test is used to verify the structural behavior of the RC wall under impact loading. The safety assessment of the building is performed with regard to different impact scenarios. The safety of the nuclear building under aircraft crash, including (1) global structural safety, (2) local structural safety, and (3) vibration safety are evaluated and discussed. The results show that the global and local structural safety of the PAB is ensured in all impact scenarios. However, the vibration safety of the building is not ensured. In accordance, the regulatory guide of United States Nuclear Regulatory Commission (U.S. NRC), shutdown of the nuclear power plant is required.

  5. Aircraft

    Science.gov (United States)

    Hibbs, B.D.; Lissaman, P.B.S.; Morgan, W.R.; Radkey, R.L.

    1998-09-22

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing`s top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gases for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well. 31 figs.

  6. Safety Analysis of Dual Purpose Metal Cask Subjected to Impulsive Loads due to Aircraft Engine Crash

    Science.gov (United States)

    Shirai, Koji; Namba, Kosuke; Saegusa, Toshiari

    In Japan, the first Interim Storage Facility of spent nuclear fuel away from reactor site is being planned to start its commercial operation around 2010, in use of dual-purpose metal cask in the northern part of Main Japan Island. Business License Examination for safety design approval has started since March, 2007. To demonstrate the more scientific and rational performance of safety regulation activities on each phase for the first license procedure, CREPEI has executed demonstration tests with full scale casks, such as drop tests onto real targets without impact limiters(1) and seismic tests subjected to strong earthquake motions(2). Moreover, it is important to develop the knowledge for the inherent security of metal casks under extreme mechanical-impact conditions, especially for increasing interest since the terrorist attacks from 11th September 2001(3)-(6). This paper presents dynamic mechanical behavior of the metal cask lid closure system caused by direct aircraft engine crash and describes calculated results (especially, leak tightness based on relative dynamic displacements between metallic seals). Firstly, the local penetration damage of the interim storage facility building by a big passenger aircraft engine crash (diameter 2.7m, length 4.3m, weight 4.4ton, impact velocity 90m/s) has been examined. The reduced velocity is calculated by the local damage formula for concrete structure with its thickness of 70cm. The load vs. time function for this reduced velocity (60m/s) is estimated by the impact analysis using Finite Element code LS-DYNA with the full scale engine model onto a hypothetically rigid target. Secondly, as the most critical scenarios for the metal cask, two impact scenarios (horizontal impact hitting the cask and vertical impact onto the lid metallic seal system) are chosen. To consider the geometry of all bolts for two lids, the gasket reaction forces and the inner pressure of the cask cavity, the detailed three dimensional FEM models are

  7. Numerical analysis of nuclear power plant structure subjected to aircraft crash

    National Research Council Canada - National Science Library

    Saberi, Reza; Alinejad, Majid; Mahdavi, Mir Omid; Sepanloo, Kamran

    2017-01-01

    An aircraft crashing into a nuclear containment may induce a series of disasters related to containment capacity, including local penetration and perforation of the containment, intensive vibrations...

  8. Numerical analysis of nuclear power plant structure subjected to aircraft crash

    National Research Council Canada - National Science Library

    Saberi, Reza; Alinejad, Majid; Mahdavi, Mir Omid; Sepanloo, Kamran

    2017-01-01

    ...) has been studied against the direct hit of Airbus A320, Boeing 707-320 and Phantom F4 aircrafts. ABAQUS/explicit finite element code has been used to carry out the three-dimensional numerical simulations...

  9. A Study on External Fire Damage of Structures subjected to Aircraft Impact

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Sang Shup [Hanyang University, Seoul (Korea, Republic of); Hahm, Daegi; Kim, Min Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    A large commercial aircraft consists of various components as fuselage, wings, fuel tank, engine etc. During a collision of the aircraft, the fuel tank with a large amount of jet fuel have a significant effect on the total load of the aircraft as well as causing explosive fire and smoke which affect the safety of the structure and equipment. US Sandia National Laboratories and Finland VTT etc. performed the test and simulation studies to evaluate the dispersion range of the fluid after the crash of liquid filled cylinder missiles. The test condition and results have been referred in this paper. The fluid modeling approach using SPH is applied to evaluate the dispersing range of the fluid, and is compared with the Brown's results. The jet fuel is idealized as particles contained in an aluminum cylinder missile, where those particles can be dispersed to the surrounding area after the missile crashes into a rigid target. The fluid model using the SPH method is briefly verified through comparison with test results, and then the modelling method is applied to a jet fuel model in an aircraft model. The dispersion analysis of jet fuel caused by aircraft impact is performed using an aircraft model for the determination of fire duration and fire affected zone in a nuclear power plant. Finally, the structural integrity of the roof of the structure during a jet fuel fire is evaluated. In this study, the filled jet fuel was modeled by using smooth particle hydrodynamics technique; jet fuel spread area following an aircraft crash was analyzed.

  10. Numerical analysis of nuclear power plant structure subjected to aircraft crash

    Science.gov (United States)

    Saberi, Reza; Alinejad, Majid; Mahdavi, Mir Omid; Sepanloo, Kamran

    2017-12-01

    An aircraft crashing into a nuclear containment may induce a series of disasters related to containment capacity, including local penetration and perforation of the containment, intensive vibrations, and fire ignited after jet fuel leakage. In this study, structural safety of a reinforced concrete containment vessel (RCCV) has been studied against the direct hit of Airbus A320, Boeing 707-320 and Phantom F4 aircrafts. ABAQUS/explicit finite element code has been used to carry out the three-dimensional numerical simulations. The impact locations identified on the nuclear containment structure are mid height of containment, center of the cylindrical portion, junction of dome and cylinder, and over the cylindrical portion close to the foundation level. The loading of the aircraft has been assigned through the corresponding reaction-time response curve. The concrete damaged plasticity model was predicted to simulate the behavior of concrete while the behavior of steel reinforcement was incorporated using elastoplastic material model. Dynamic loading conditions were considered using dynamic increase factor. The mid height of containment and center of cylindrical portion have been found to experience most severe deformation against each aircraft crash. It has also been found that compression damage in concrete is not critical at none of the impact locations.

  11. Numerical analysis of nuclear power plant structure subjected to aircraft crash

    Science.gov (United States)

    Saberi, Reza; Alinejad, Majid; Mahdavi, Mir Omid; Sepanloo, Kamran

    2017-10-01

    An aircraft crashing into a nuclear containment may induce a series of disasters related to containment capacity, including local penetration and perforation of the containment, intensive vibrations, and fire ignited after jet fuel leakage. In this study, structural safety of a reinforced concrete containment vessel (RCCV) has been studied against the direct hit of Airbus A320, Boeing 707-320 and Phantom F4 aircrafts. ABAQUS/explicit finite element code has been used to carry out the three-dimensional numerical simulations. The impact locations identified on the nuclear containment structure are mid height of containment, center of the cylindrical portion, junction of dome and cylinder, and over the cylindrical portion close to the foundation level. The loading of the aircraft has been assigned through the corresponding reaction-time response curve. The concrete damaged plasticity model was predicted to simulate the behavior of concrete while the behavior of steel reinforcement was incorporated using elastoplastic material model. Dynamic loading conditions were considered using dynamic increase factor. The mid height of containment and center of cylindrical portion have been found to experience most severe deformation against each aircraft crash. It has also been found that compression damage in concrete is not critical at none of the impact locations.

  12. Dynamic Response Analysis of Storage Cask Lid Structure Subjected to Lateral Impact Load of Aircraft Engine Crash

    Energy Technology Data Exchange (ETDEWEB)

    Almomania, Belal; Kang, Hyun Gook [KAIST, Daejeon (Korea, Republic of); Lee, Sanghoon [Keimyung Univ., Daegu (Korea, Republic of)

    2015-10-15

    Several numerical methods and tests have been carried out to measure the capability of storage cask to withstand extreme impact loads. Testing methods are often constrained by cost, and difficulty in preparation for several impact conditions with different applied loads, and areas of impact. Instead, analytic method is an acceptable process that can easily apply different impact conditions for the evaluation of cask integrity. The aircraft engine impact is considered as one of the most critical impact accidents on the storage cask that significantly affects onto the lid closure system and may cause a considerable release of radioactive materials. This paper presents a method for evaluating the dynamic responses of one upper metal cask lid closure without impact limiters subjected to lateral impact of an aircraft engine with respect to variation of the impact velocity. An assessment method to predict damage response due to the lateral engine impact onto metal storage cask has been studied by using computer code LS-DYNA. The dynamic behavior of the lid movements was successfully calculated by utilizing a simplified finite element cask model, which showed a good agreement with the previous research. The simulation analyses results showed that no significant plastic deformation for bolts, lid, and the cask body. In this study, the lid opening and sliding displacements are considered as the major factors in initiating the leakage path. This analysis may be useful for evaluating the instantaneous leakage rates in a connection with the sliding and opening displacements between the lid and the flange to ensure that the radiological consequences caused by an aircraft engine crash accident during the storage phase are within the permissible level.

  13. Effect of temperature on composite sandwich structures subjected to low velocity impact. [aircraft construction materials

    Science.gov (United States)

    Sharma, A. V.

    1980-01-01

    The effect of low velocity projectile impact on sandwich-type structural components was investigated. The materials used in the fabrication of the impact surface were graphite-, Kevlar-, and boron-fibers with appropriate epoxy matrices. The testing of the specimens was performed at moderately low- and high-temperatures as well as at room temperature to assess the impact-initiated strength degradation of the laminates. Eleven laminates with different stacking sequences, orientations, and thicknesses were tested. The low energy projectile impact is considered to simulate the damage caused by runway debris, the dropping of the hand tools during servicing, etc., on the secondary aircraft structures fabricated with the composite materials. The results show the preload and the impact energy combinations necessary to cause catastrophic failure in the laminates tested. A set of faired curves indicating the failure thresholds is shown separately for the tension-and compression-loaded laminates. The specific-strengths and -modulii for the various laminates tested are also given.

  14. Long-term airborne black carbon measurements on a Lufthansa passenger aircraft

    Science.gov (United States)

    Ditas, Jeannine; Su, Hang; Scharffe, Dieter; Wang, Siwen; Zhang, Yuxuan; Brenninkmeijer, Carl; Pöschl, Ulrich; Cheng, Yafang

    2016-04-01

    Aerosol particles containing black carbon are the most absorbing component of incoming solar radiation and exert a significant positive radiative forcing thus forming next to CO² the strongest component of current global warming (Bond, 2013). Nevertheless, the role of black carbon particles and especially their complex interaction with clouds needs further research which is hampered by the limited experimental data, especially observations in the free and upper troposphere, and in the UTLS (upper troposphere and lower stratosphere). Many models underestimate the global atmospheric absorption attributable to black carbon by a factor of almost 3 (Bond, 2013). In August 2014, a single particle soot photometer was included in the extensive scientific payload of the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) project. CARIBIC is in operation since 1997 (with an interruption for 2002-2005) and carries out systematic observations at 10-12 km altitude. For this a special air freight container combining different instruments is transported on a monthly basis using a Lufthansa Airbus A340-600 passenger aircraft with destinations from 120°W to 120°E and 10°N to 75°N. The container has equipment for trace gas analyses and sampling and aerosol analyses and sampling and is connected to an inlet system that is part of the aircraft which contains a camera and DOAS remote sensing system. The integration of a single particle soot photometer (SP2) offers the possibility for the first long-term measurement of global distribution of black carbon and so far flights up to November 2015 have been conducted with more than 400 flight hours. So far the SP2 measurements have been analysed for flights over four continents from Munich to San Francisco, Sao Paulo, Tokyo, Beijing, Cape Town, Los Angeles and Hong Kong). The first measurements show promising results of black carbon measurements. Background concentrations in the UTLS

  15. Long-term aircraft noise exposure and body mass index, waist circumference, and type 2 diabetes: a prospective study.

    Science.gov (United States)

    Eriksson, Charlotta; Hilding, Agneta; Pyko, Andrei; Bluhm, Gösta; Pershagen, Göran; Östenson, Claes-Göran

    2014-07-01

    Long-term aircraft noise exposure may increase the risk of cardiovascular disease, but no study has investigated chronic effects on the metabolic system. The aim of this study was to investigate effects of long-term aircraft noise exposure on body mass index (BMI), waist circumference, and type 2 diabetes. Furthermore, we explored the modifying effects of sleep disturbance. This prospective cohort study of residents of Stockholm County, Sweden, followed 5,156 participants with normal baseline oral glucose tolerance tests (OGTT) for up to 10 years. Exposure to aircraft noise was estimated based on residential history. Information on outcomes and confounders was obtained from baseline and follow-up surveys and examinations, and participants who developed prediabetes or type 2 diabetes were identified by self-reported physician diagnosis or OGTT at follow-up. Adjusted associations were assessed by linear, logistic, and random-effects models. The mean (± SD) increases in BMI and waist circumference during follow-up were 1.09 ± 1.97 kg/m2 and 4.39 ± 6.39 cm, respectively. The cumulative incidence of prediabetes and type 2 diabetes was 8% and 3%, respectively. Based on an ordinal noise variable, a 5-dB(A) increase in aircraft noise was associated with a greater increase in waist circumference of 1.51 cm (95% CI: 1.13, 1.89), fully adjusted. This association appeared particularly strong among those who did not change their home address during the study period, which may be a result of lower exposure misclassification. However, no clear associations were found for BMI or type 2 diabetes. Furthermore, sleep disturbances did not appear to modify the associations with aircraft noise. Long-term aircraft noise exposure may be linked to metabolic outcomes, in particular increased waist circumference.

  16. Long-Term Aircraft Noise Exposure and Body Mass Index, Waist Circumference, and Type 2 Diabetes: A Prospective Study

    Science.gov (United States)

    Hilding, Agneta; Pyko, Andrei; Bluhm, Gösta; Pershagen, Göran; Östenson, Claes-Göran

    2014-01-01

    Background: Long-term aircraft noise exposure may increase the risk of cardiovascular disease, but no study has investigated chronic effects on the metabolic system. Objectives: The aim of this study was to investigate effects of long-term aircraft noise exposure on body mass index (BMI), waist circumference, and type 2 diabetes. Furthermore, we explored the modifying effects of sleep disturbance. Methods: This prospective cohort study of residents of Stockholm County, Sweden, followed 5,156 participants with normal baseline oral glucose tolerance tests (OGTT) for up to 10 years. Exposure to aircraft noise was estimated based on residential history. Information on outcomes and confounders was obtained from baseline and follow-up surveys and examinations, and participants who developed prediabetes or type 2 diabetes were identified by self-reported physician diagnosis or OGTT at follow-up. Adjusted associations were assessed by linear, logistic, and random-effects models. Results: The mean (± SD) increases in BMI and waist circumference during follow-up were 1.09 ± 1.97 kg/m2 and 4.39 ± 6.39 cm, respectively. The cumulative incidence of prediabetes and type 2 diabetes was 8% and 3%, respectively. Based on an ordinal noise variable, a 5-dB(A) increase in aircraft noise was associated with a greater increase in waist circumference of 1.51 cm (95% CI: 1.13, 1.89), fully adjusted. This association appeared particularly strong among those who did not change their home address during the study period, which may be a result of lower exposure misclassification. However, no clear associations were found for BMI or type 2 diabetes. Furthermore, sleep disturbances did not appear to modify the associations with aircraft noise. Conclusions: Long-term aircraft noise exposure may be linked to metabolic outcomes, in particular increased waist circumference. Citation: Eriksson C, Hilding A, Pyko A, Bluhm G, Pershagen G, Östenson CG. 2014. Long-term aircraft noise exposure and

  17. The effect of exposure duration on the subjective discomfort of aircraft cabin noise.

    Science.gov (United States)

    Huang, Yu; Jiang, Weikang

    2017-01-01

    The time dependency for subjective responses to noise has been a controversial question over many years. For durations of up to 10 min, the discomfort produced by three levels of noise (ie 60, 70 and 80 dBA) was investigated in this experimental study to determine the relation of discomfort to the time duration of noise. The rate of increase in discomfort with increasing duration was 1.5 dB per doubling of exposure duration, whereas it is currently assumed to be 3 dB per doubling of exposure duration. The sound dose level (SDL) was proposed to predict the discomfort caused by noise of long duration. The combination of SDL and vibration dose value (VDV) provided more consistent estimates of the equivalent comfort contours between noise and vibration over durations from 2 to 32 s than the combination of sound exposure level and VDV or that of sound pressure level and r.m.s. acceleration. Practitioner Summary: The discomfort produced by noise of long duration can be well predicted from a new definition of sound dose level, where the discomfort increases at 1.5 dB per doubling of exposure duration.

  18. 38 CFR 17.258 - Terms and conditions to which awards are subject.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Terms and conditions to which awards are subject. 17.258 Section 17.258 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS MEDICAL Grants for Exchange of Information § 17.258 Terms and conditions to which awards...

  19. Subjectivity

    Directory of Open Access Journals (Sweden)

    Jesús Vega Encabo

    2015-11-01

    Full Text Available In this paper, I claim that subjectivity is a way of being that is constituted through a set of practices in which the self is subject to the dangers of fictionalizing and plotting her life and self-image. I examine some ways of becoming subject through narratives and through theatrical performance before others. Through these practices, a real and active subjectivity is revealed, capable of self-knowledge and self-transformation. 

  20. Products of Ozone-initiated Chemistry during 4-hour Exposures of Human Subjects in a Simulated Aircraft Cabin

    DEFF Research Database (Denmark)

    Weschler, Charles J.; Wisthaler, Armin; Tamás, Gyöngyi

    2006-01-01

    Proton-transfer-reaction mass spectrometry (PTR-MS) was used to examine organic compounds in the air of a simulated aircraft cabin under four conditions: low ozone, low air exchange rate; low ozone, high air exchange rate; high ozone, low air exchange rate; high ozone, high air exchange rate...

  1. Attempting to train a digital human model to reproduce human subject reach capabilities in an ejection seat aircraft

    NARCIS (Netherlands)

    Zehner, G.F.; Hudson, J.A.; Oudenhuijzen, A.

    2006-01-01

    From 1997 through 2002, the Air Force Research Lab and TNO Defence, Security and Safety (Business Unit Human Factors) were involved in a series of tests to quantify the accuracy of five Human Modeling Systems (HMSs) in determining accommodation limits of ejection seat aircraft. The results of these

  2. Correlation between subjective assessments of local thermal discomfort and thermal manikin measurements in a simulated aircraft cabin

    DEFF Research Database (Denmark)

    Zukowska, Daria; Strøm-Tejsen, Peter; Jama, Agnieszka

    2005-01-01

    The thermal environment in a 21-seat simulated section of an aircraft cabin installed in a climate chamber was investigated. Using two thermal manikins and fourteen heated cylin-ders to represent passengers, measurements were carried out at cabin temperatures of 20.6°C, 23.3°C and 26.1°C (69°F, 74...

  3. Dyslipidemia in HIV-1 Infected Subjects with Short Term Usage of ...

    African Journals Online (AJOL)

    Dyslipidemia in HIV-1 Infected Subjects with Short Term Usage of Highly Active Antiretroviral Therapy (HAART) in Benin City, Nigeria. O. G. Igharo, T.L. Olawoye, H.B. Osadolor, F. A. Idomeh, O. J. Osunbor, A. O. Osagie, O.C. Iyamu ...

  4. 37 CFR 1.710 - Patents subject to extension of the patent term.

    Science.gov (United States)

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Patents subject to extension of the patent term. 1.710 Section 1.710 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES Adjustment and Extension...

  5. Unmanned aircraft systems

    Science.gov (United States)

    Unmanned platforms have become increasingly more common in recent years for acquiring remotely sensed data. These aircraft are referred to as Unmanned Airborne Vehicles (UAV), Remotely Piloted Aircraft (RPA), Remotely Piloted Vehicles (RPV), or Unmanned Aircraft Systems (UAS), the official term used...

  6. Leveraging output term co-occurrence frequencies and latent associations in predicting medical subject headings.

    Science.gov (United States)

    Kavuluru, Ramakanth; Lu, Yuan

    2014-11-01

    Trained indexers at the National Library of Medicine (NLM) manually tag each biomedical abstract with the most suitable terms from the Medical Subject Headings (MeSH) terminology to be indexed by their PubMed information system. MeSH has over 26,000 terms and indexers look at each article's full text while assigning the terms. Recent automated attempts focused on using the article title and abstract text to identify MeSH terms for the corresponding article. Most of these approaches used supervised machine learning techniques that use already indexed articles and the corresponding MeSH terms. In this paper, we present a new indexing approach that leverages term co-occurrence frequencies and latent term associations computed using MeSH term sets corresponding to a set of nearly 18 million articles already indexed with MeSH terms by indexers at NLM. The main goal of our study is to gauge the potential of output label co-occurrences, latent associations, and relationships extracted from free text in both unsupervised and supervised indexing approaches. In this paper, using a novel and purely unsupervised approach, we achieve a micro-F-score that is comparable to those obtained using supervised machine learning techniques. By incorporating term co-occurrence and latent association features into a supervised learning framework, we also improve over the best results published on two public datasets.

  7. The Severe Respiratory Insufficiency Questionnaire for Subjects With COPD With Long-Term Oxygen Therapy.

    Science.gov (United States)

    Walterspacher, Stephan; July, Johanna; Kohlhäufl, Martin; Rzehak, Peter; Windisch, Wolfram

    2016-09-01

    Respiratory insufficiency in COPD may present as hypoxic and/or hypercapnic respiratory failure treated with long-term oxygen therapy (LTOT) and/or noninvasive ventilation (NIV) with LTOT. The Severe Respiratory Insufficiency Questionnaire (SRI) is a tool for the assessment of health-related quality of life (HRQOL) in subjects receiving NIV. However, it remains unclear whether the SRI is also capable of assessing and discriminating HRQOL in subjects receiving LTOT. Stable subjects with COPD receiving LTOT or NIV + LTOT (NIV) were prospectively recruited and completed the SRI, lung function tests, and blood gases. Confirmatory factor analysis for construct validity and internal consistency reliability were calculated. One hundred fifty-five subjects were included (113 LTOT, 42 NIV). The Cronbach α coefficient of the 7 subscales ranged between 0.69 and 0.89 (LTOT) and between 0.79 and 0.93 (NIV), respectively. In both groups, confirmatory factor analysis revealed a one-factor model for the SRI summary scale; in 5 subscales, one- or 2-factor models could be established. Group differences in the SRI subsets were all P <.05 (except for physical functioning) with higher scores in subjects receiving NIV. The SRI showed high reliability and validity in subjects with COPD receiving LTOT. Subjects receiving LTOT had lower SRI scores, indicating a poorer HRQOL compared with subjects with established NIV and LTOT. Copyright © 2016 by Daedalus Enterprises.

  8. Subjective memory ability and long-term forgetting in patients referred for neuropsychological assessment

    Directory of Open Access Journals (Sweden)

    Sieberen Pieter Van Der Werf

    2016-05-01

    Full Text Available It has been suggested that the memory complaints of patients who are not impaired on formal memory tests may reflect accelerated forgetting. We examined this hypothesis by comparing the one-week delayed recall and recognition test performance of outpatients who were referred for neuropsychological assessment and who had normal memory performance during standard memory assessment with that of a non-patient control group. Both groups performed equally in verbal learning and delayed recall. However, after one week, the patients performed worse than controls on both recall and recognition tests. Although subjective memory ability predicted short-term memory function in patients, it did not predict long-term delayed forgetting rates in either the patients or controls. Thus, long-term delayed recall and recognition intervals provided no additional value to explain poor subjective memory ability in the absence of objective memory deficits.

  9. Short- versus long-term prediction of dementia among subjects with low and high educational levels.

    Science.gov (United States)

    Chary, Emilie; Amieva, Hélène; Pérès, Karine; Orgogozo, Jean-Marc; Dartigues, Jean-François; Jacqmin-Gadda, Hélène

    2013-09-01

    Using simple measures of cognition and disability in a prospective community-living cohort of normal elderly persons, the main objectives of our study were to distinguish short- and long-term predictors for dementia according to educational level and to propose a tool for early detection of subjects at high risk of dementia. Data derived from the French cohort study Paquid (Personnes Agées QUID), which included 3777 subjects, older than 65 years of age, who were followed for a 20-year period. The risk of dementia at 3 years and 10 years was estimated by logistic regression for repeated measures combining data from all the 3- and 10-year windows throughout the follow-up. Predictors included disability assessed by the number of dependent items among four instrumental activities of daily living (IADLs), four neuropsychological tests, five Mini-Mental State Examination (MMSE) subtests, and four items of subjective memory complaints. Of the 2882 included subjects, the number of IADLs remained a predictor of short- and long-term conversion to dementia for those with low educational level (combined with only one cognitive test) whereas the best predictors for more educated subjects combined subjective memory complaints and memory and executive function tests. The episodic memory subtest was the only predictive MMSE subtest. In the high-education-level group, the areas under the receiver-operating characteristic curve of the selected models were 0.85 for 3-year prediction and 0.78 for 10-year prediction. Early predictors of dementia are different according to educational level. Among subjects reaching the secondary school level, early detection of those at high risk of dementia is possible with good predictive performance, with a few simple objective and subjective cognitive evaluations. Copyright © 2013 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

  10. Subjective Sleep Quality and hormonal modulation in long-term yoga practitioners.

    Science.gov (United States)

    Vera, Francisca M; Manzaneque, Juan M; Maldonado, Enrique F; Carranque, Gabriel A; Rodriguez, Francisco M; Blanca, Maria J; Morell, Miguel

    2009-07-01

    Yoga represents a fascinating mind-body approach, wherein body movements (asana), breathing exercises (pranayama) and meditation are integrated into a single multidimensional practice. Numerous beneficial mental and physical effects have been classically ascribed to this holistic ancient method. The purpose of the present study has been to examine the effects of long-term yoga practice on Subjective Sleep Quality (SSQ) and on several hormonal parameters of the hypothalamus-pituitary-adrenal (HPA) axis. Twenty-six subjects (16 experimental and 10 controls) were recruited to be part of the study. Experimental subjects were regular yoga practitioners with a minimum of 3 years of practice. Blood samples for the quantification of adrenocorticotropic hormone (ACTH), cortisol and dehydroepiandrosterone sulphate (DHEA-S) were drawn from all subjects. Likewise, the Pittsburgh Sleep Quality Index (PSQI) was employed to assess SSQ. As statistical analysis, Mann-Whitney U-test was performed. The yoga group displayed lower PSQI scores and higher blood cortisol levels than control subjects. Therefore, it can be concluded that long-term yoga practice is associated with significant psycho-biological differences, including better sleep quality as well as a modulatory action on the levels of cortisol. These preliminary results suggest interesting clinical implications which should be further researched.

  11. Long-term endurance training increases serum cathepsin S levels in healthy female subjects.

    Science.gov (United States)

    Sponder, M; Minichsdorfer, C; Campean, I-A; Emich, M; Fritzer-Szekeres, M; Litschauer, B; Strametz-Juranek, J

    2017-11-27

    Circulating cathepsin S (CS) has been associated with a lower risk for breast cancer in a large Swedish cohort. Long-term physical activity has been shown to have beneficial effects on the development of various cancer subtypes, in particular breast and colorectal cancers. The aim of this study was to investigate the effect of long-term endurance sport on CS levels in females. Thirty-six of 40 subjects completed the study. Subjects were told to increase their activity pensum for 8 months reaching 150 min/week moderate or 75 min/week intense exercise. Ergometries were performed at the beginning and the end of the study to prove/quantify the performance gain. Blood samples were drawn at baseline and every 2 months. Serum CS levels were measured by ELISA. To analyse the change and the progression of CS, Wilcoxon rank sum and Friedman tests were used. The sportive group (performance gain by > 4.9%) showed a significant increase of CS levels from 3.32/2.73/4.09 to 4.00/3.09/5.04 ng/ml (p = 0.008) corresponding to an increase of 20.5%. We could show a significant increase of circulating CS levels in healthy female subjects induced by long-term physical activity. CS, occurring in the tumour microenvironment, is well-known to promote tumour growth, e.g. by ameliorating angiogenesis. However, the role of circulating CS in cancer growth is not clear. As physical activity is known as preventive intervention, in particular concerning breast and colorectal cancers, and long-term physical activity leads to an increase of CS levels in female subjects, circulating CS might even be involved in this protective effect. Clinical trial registration: NCT02097199.

  12. The study of subjective feelings of loneliness older women in terms of suicide risk

    Directory of Open Access Journals (Sweden)

    Kudryashov E.L.

    2014-12-01

    Full Text Available The results of the study of subjective feeling lonely older women and their actual social status in terms of the propensity to suicidal behavior. Hypothesized that the level of suicide risk in older women reveals a closer connection with the severity of subjective feelings of loneliness than with the degree of objective social isolation. The study involved 52 women aged 55 to 75 years old who do not have mental disorders and debilitating physical illness. The main methods of study was the analysis of medical records, interview and psychological testing formalized. Data used for U-Mann-Whitney test, H-Kruskal-Wallis test, and Pearson criterion 2 Spearman rank correlation method. It is shown that the severity of suicidal risk in the studied sample is really linked to the level of subjective feelings of loneliness (p≤0,05, in respect of the same objective social isolation test found no such relationship.

  13. LONG TERM EFFECT OF CYRIAX PHYSIOTHERPY WITH SUPERVISED EXERCISE PROGRAM IN SUBJECTS WITH TENNIS ELBOW

    Directory of Open Access Journals (Sweden)

    Pallavi Shridhar Thakare

    2014-06-01

    Full Text Available Background: The purpose is to find long term effect of Cyriax physiotherapy with supervised exercise program in the reduction of pain and improvement of functional ability for subjects with tennis elbow. Method: An experimental study design, 30 subjects with Tennis Elbow randomized 15 subjects each into Study and Control group. Control group received Supervised Exercise program while Study group received Cyriax Physiotherapy with Supervised exercises program thrice in a week for 4 weeks and post intervention follow up after 2 weeks. Outcome measurements were measured for pain using Visual analogue Scale (VAS and Patient Rated Tennis Elbow Evaluation (PRTEE for functional ability. Results: There is no statistically significant difference in pre- intervention means of VAS and PRTEE when compared between the groups using independent ‘t’ test as a parametric and Mann Whitney U test as a non-parametric test. When means of post intervention and follow-up measurements were compared there is a statistically significant (p<0.05 difference in VAS and PRTEE scores between the groups. However greater percentage of improvements was obtained in study group than control group. Conclusion: It is concluded that there is significant long term effect with greater percentage of improvement in pain and functional ability up to 2 weeks follow-up following 4 weeks of combined Cyriax physiotherapy with supervised exercise program than only supervised exercise program for subjects with tennis elbow.

  14. Metacognition of visual short-term memory: Dissociation between objective and subjective components of VSTM

    Directory of Open Access Journals (Sweden)

    Silvia eBona

    2013-02-01

    Full Text Available The relationship between the objective accuracy of visual-short term memory (VSTM representations and their subjective conscious experience is unknown. We investigated this issue by assessing how the objective and subjective components of VSTM in a delayed cue-target orientation discrimination task are affected by intervening distracters. On each trial, participants were shown a memory cue (a grating, the orientation of which they were asked to hold in memory. On approximately half of the trials, a distractor grating appeared during the maintenance interval; its orientation was either identical to that of the memory cue, or it differed by 10 or 40 degrees. The distractors were masked and presented briefly, so they were only consciously perceived on a subset of trials. At the end of the delay period, a memory test probe was presented, and participants were asked to indicate whether it was tilted to the left or right relative to the memory cue (VSTM accuracy; objective performance. In order to assess subjective metacognition, participants were asked indicate the vividness of their memory for the original memory cue. Finally, participants were asked rate their awareness of the distracter. Results showed that objective VSTM performance was impaired by distractors only when the distractors were very different from the cue, and that this occurred with both subjectively visible and invisible distractors. Subjective metacognition, however, was impaired by distractors of all orientations, but only when these distractors were subjectively invisible. Our results thus indicate that the objective and subjective components of VSTM are to some extent dissociable.

  15. Short-term interval training alters brain glucose metabolism in subjects with insulin resistance.

    Science.gov (United States)

    Honkala, Sanna M; Johansson, Jarkko; Motiani, Kumail K; Eskelinen, Jari-Joonas; Virtanen, Kirsi A; Löyttyniemi, Eliisa; Knuuti, Juhani; Nuutila, Pirjo; Kalliokoski, Kari K; Hannukainen, Jarna C

    2017-01-01

    Brain insulin-stimulated glucose uptake (GU) is increased in obese and insulin resistant subjects but normalizes after weight loss along with improved whole-body insulin sensitivity. Our aim was to study whether short-term exercise training (moderate intensity continuous training (MICT) or sprint interval training (SIT)) alters substrates for brain energy metabolism in insulin resistance. Sedentary subjects ( n = 21, BMI 23.7-34.3 kg/m2, age 43-55 y) with insulin resistance were randomized into MICT ( n = 11, intensity≥60% of VO2peak) or SIT ( n = 10, all-out) groups for a two-week training intervention. Brain GU during insulin stimulation and fasting brain free fatty acid uptake (FAU) was measured using PET. At baseline, brain GU was positively associated with the fasting insulin level and negatively with the whole-body insulin sensitivity. The whole-body insulin sensitivity improved with both training modes (20%, p = 0.007), while only SIT led to an increase in aerobic capacity (5%, p = 0.03). SIT also reduced insulin-stimulated brain GU both in global cortical grey matter uptake (12%, p = 0.03) and in specific regions ( p Brain FAU remained unchanged after the training in both groups. These findings show that short-term SIT effectively decreases insulin-stimulated brain GU in sedentary subjects with insulin resistance.

  16. Moderate alcohol consumption predicts long-term mortality in elderly subjects with chronic heart failure.

    Science.gov (United States)

    Gargiulo, G; Testa, G; Cacciatore, F; Mazzella, F; Galizia, G; Della-Morte, D; Langellotto, A; Pirozzi, G; Ferro, G; Ferrara, N; Rengo, F; Abete, P

    2013-01-01

    Moderate alcohol consumption is related to a reduction of mortality. However, this phenomenon is not well established in the elderly, especially in the presence of chronic heart failure (CHF). The aim of the study was to verify the effect of moderate alcohol consumption on 12-year mortality in elderly community-dwelling with and without CHF. community-dwelling from 5 regions of Italy. A cohort of 1332 subjects aged 65 and older. Mortality after 12-year follow-up in elderly subjects (≥65 years old) with and without CHF was studied. Moderate alcohol consumption was considered ≤250 ml/day (drinkers). In the absence of CHF (n=947), mortality was 42.2% in drinkers vs. 53.7% in non-drinker elderly subjects (p=0.021). In contrast, in the presence of CHF (n=117), mortality was 86.5% in drinkers vs. 69.7% in non-drinker elderly subjects (p=0.004). Accordingly, Cox regression analysis shows that a moderate alcohol consumption is protective of mortality in the absence (HR=0.79; CI 95% 0.66-0.95; pmoderate alcohol consumption is associated with an increased long-term mortality risk in the elderly in the presence of CHF.

  17. Technique for Reducing the Effects of Nonlinear Terms on Electric Field Measurements of Electric Field Sensor Arrays on Aircraft Platforms

    National Research Council Canada - National Science Library

    D M Mach

    2015-01-01

      A generalized technique has been developed that reduces the contributions of nonlinear effects that occur during measurements of natural electric fields around thunderstorms by an array of field mills on an aircraft...

  18. Long-term clearance from small airways in subjects with ciliary dysfunction

    Directory of Open Access Journals (Sweden)

    Hjelte Lena

    2006-05-01

    Full Text Available Abstract The objective of this study was to investigate if long-term clearance from small airways is dependent on normal ciliary function. Six young adults with primary ciliary dyskinesia (PCD inhaled 111 Indium labelled Teflon particles of 4.2 μm geometric and 6.2 μm aerodynamic diameter with an extremely slow inhalation flow, 0.05 L/s. The inhalation method deposits particles mainly in the small conducting airways. Lung retention was measured immediately after inhalation and at four occasions up to 21 days after inhalation. Results were compared with data from ten healthy controls. For additional comparison three of the PCD subjects also inhaled the test particles with normal inhalation flow, 0.5 L/s, providing a more central deposition. The lung retention at 24 h in % of lung deposition (Ret24 was higher (p 24 with slow inhalation flow was 73.9 ± 1.9 % compared to 68.9 ± 7.5 % with normal inhalation flow in the three PCD subjects exposed twice. During day 7–21 the three PCD subjects exposed twice cleared 9 % with normal flow, probably representing predominantly alveolar clearance, compared to 19 % with slow inhalation flow, probably representing mainly small airway clearance. This study shows that despite ciliary dysfunction, clearance continues in the small airways beyond 24 h. There are apparently additional clearance mechanisms present in the small airways.

  19. Long-term wheat germ intake beneficially affects plasma lipids and lipoproteins in hypercholesterolemic human subjects.

    Science.gov (United States)

    Cara, L; Armand, M; Borel, P; Senft, M; Portugal, H; Pauli, A M; Lafont, H; Lairon, D

    1992-02-01

    In previous short-term studies in rats and humans, the ingestion of raw wheat germ lowered plasma triglycerides and cholesterol. Thus, the present study was designed to investigate the possible long-term effects of wheat germ intake. Diet supplementation with raw wheat germ or partially defatted wheat germ was tested in two separate groups of 10 and 9 free-living human subjects, respectively. They all exhibited hypercholesterolemia (6.14-9.67 mmol/L cholesterol) and 11 had hypertriglyceridemia. None was diabetic. Fasting blood samples were taken at the beginning of the study, after 4 wk of 20 g/d wheat germ intake, after 14 additional weeks of 30 g/d wheat germ intake and after 12 wk without any supplementation. Dietary records were kept for seven and three consecutive days, before and during the wheat germ intake periods, respectively. Raw wheat germ intake significantly decreased plasma cholesterol (-8.7%) and tended to reduce VLDL cholesterol (-19.6%) after 4 wk. After 14 additional weeks, plasma cholesterol (-7.2%) and LDL cholesterol (-15.4%) remained lower and plasma triglycerides (-11.3%) tended to be lower. The apo B:apo A1 ratio significantly decreased after both periods. Partially defatted wheat germ transiently decreased plasma triglycerides and cholesterol after a 4-wk intake. The present data indicate that wheat germ reduces cholesterolemia in the long term and could play a beneficial role in the dietary management of type IIa and IIb hyperlipidemia.

  20. Nonparametric Monitoring for Geotechnical Structures Subject to Long-Term Environmental Change

    Directory of Open Access Journals (Sweden)

    Hae-Bum Yun

    2011-01-01

    Full Text Available A nonparametric, data-driven methodology of monitoring for geotechnical structures subject to long-term environmental change is discussed. Avoiding physical assumptions or excessive simplification of the monitored structures, the nonparametric monitoring methodology presented in this paper provides reliable performance-related information particularly when the collection of sensor data is limited. For the validation of the nonparametric methodology, a field case study was performed using a full-scale retaining wall, which had been monitored for three years using three tilt gauges. Using the very limited sensor data, it is demonstrated that important performance-related information, such as drainage performance and sensor damage, could be disentangled from significant daily, seasonal and multiyear environmental variations. Extensive literature review on recent developments of parametric and nonparametric data processing techniques for geotechnical applications is also presented.

  1. Relevance of a subjective quality of life questionnaire for long-term homeless persons with schizophrenia.

    Science.gov (United States)

    Girard, V; Tinland, A; Bonin, J P; Olive, F; Poule, J; Lancon, C; Apostolidis, T; Rowe, M; Greacen, T; Simeoni, M C

    2017-02-17

    Increasing numbers of programs are addressing the specific needs of homeless people with schizophrenia in terms of access to housing, healthcare, basic human rights and other domains. Although quality of life scales are being used to evaluate such programs, few instruments have been validated for people with schizophrenia and none for people with schizophrenia who experience major social problems such as homelessness. The aim of the present study was to validate the French version of the S-QoL a self-administered, subjective quality of life questionnaire specific to schizophrenia for people with schizophrenia who are homeless. In a two-step process, the S-QoL was first administered to two independent convenience samples of long-term homeless people with schizophrenia in Marseille, France. The objective of the first step was to analyse the psychometric properties of the S-QoL. The objective of the second step was to examine, through qualitative interviews with members of the population in question, the relevance and acceptability of the principle quality of life indicators used in the S-QoL instrument. Although the psychometric characteristics of the S-QoL were found to be globally satisfactory, from the point of view of the people being interviewed, acceptability was poor. Respondents frequently interrupted participation complaining that questionnaire items did not take into account the specific context of life on the streets. Less intrusive questions, more readily understandable vocabulary and greater relevance to subjects' living conditions are needed to improve the S-QoL questionnaire for this population. A modular questionnaire with context specific sections or specific quality of life instruments for socially excluded populations may well be the way forward.

  2. Inverse modeling of the 137Cs source term of the Fukushima Dai-ichi Nuclear Power Plant accident constrained by a deposition map monitored by aircraft.

    Science.gov (United States)

    Yumimoto, Keiya; Morino, Yu; Ohara, Toshimasa; Oura, Yasuji; Ebihara, Mitsuru; Tsuruta, Haruo; Nakajima, Teruyuki

    2016-11-01

    The amount of 137Cs released by the Fukushima Dai-ichi Nuclear Power Plant accident of 11 March 2011 was inversely estimated by integrating an atmospheric dispersion model, an a priori source term, and map of deposition recorded by aircraft. An a posteriori source term refined finer (hourly) variations comparing with the a priori term, and estimated 137Cs released 11 March to 2 April to be 8.12 PBq. Although time series of the a posteriori source term was generally similar to those of the a priori source term, notable modifications were found in the periods when the a posteriori source term was well-constrained by the observations. Spatial pattern of 137Cs deposition with the a posteriori source term showed better agreement with the 137Cs deposition monitored by aircraft. The a posteriori source term increased 137Cs deposition in the Naka-dori region (the central part of Fukushima Prefecture) by 32.9%, and considerably improved the underestimated a priori 137Cs deposition. Observed values of deposition measured at 16 stations and surface atmospheric concentrations collected on a filter tape of suspended particulate matter were used for validation of the a posteriori results. A great improvement was found in surface atmospheric concentration on 15 March; the a posteriori source term reduced root mean square error, normalized mean error, and normalized mean bias by 13.4, 22.3, and 92.0% for the hourly values, respectively. However, limited improvements were observed in some periods and areas due to the difficulty in simulating accurate wind fields and the lack of the observational constraints. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Controlled Terms or Free Terms? A JavaScript Library to Utilize Subject Headings and Thesauri on the Web

    Directory of Open Access Journals (Sweden)

    Shun Nagaya

    2011-10-01

    Full Text Available There are two types of keywords used as metadata: controlled terms and free terms. Free terms have the advantage that metadata creators can freely select keywords, but there also exists a disadvantage that the information retrieval recall ratio might be reduced. The recall ratio can be improved by using controlled terms. But creating and maintaining controlled vocabularies has an enormous cost. In addition, many existing controlled vocabularies are published in formats less suitable for programming. We introduce a JavaScript library called “covo.js” that enables us to make use of controlled vocabularies as metadata for the organization of web pages.

  4. Negative emotion enhances mnemonic precision and subjective feelings of remembering in visual long-term memory.

    Science.gov (United States)

    Xie, Weizhen; Zhang, Weiwei

    2017-09-01

    Negative emotion sometimes enhances memory (higher accuracy and/or vividness, e.g., flashbulb memories). The present study investigates whether it is the qualitative (precision) or quantitative (the probability of successful retrieval) aspect of memory that drives these effects. In a visual long-term memory task, observers memorized colors (Experiment 1a) or orientations (Experiment 1b) of sequentially presented everyday objects under negative, neutral, or positive emotions induced with International Affective Picture System images. In a subsequent test phase, observers reconstructed objects' colors or orientations using the method of adjustment. We found that mnemonic precision was enhanced under the negative condition relative to the neutral and positive conditions. In contrast, the probability of successful retrieval was comparable across the emotion conditions. Furthermore, the boost in memory precision was associated with elevated subjective feelings of remembering (vividness and confidence) and metacognitive sensitivity in Experiment 2. Altogether, these findings suggest a novel precision-based account for emotional memories. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Short and long-term effects of sham-controlled prefrontal EEG-neurofeedback training in healthy subjects

    NARCIS (Netherlands)

    Engelbregt, H.J.; Keeser, D.; van Eijk, L.; Suiker, E.M.; Eichhorn, D.; Karch, S.; Deijen, J.B.; Pogarell, O.

    2016-01-01

    Objective: In this study we evaluated long-term effects of frontal beta EEG-neurofeedback training (E-NFT) on healthy subjects. We hypothesized that E-NFT can change frontal beta activity in the long-term and that changes in frontal beta EEG activity are accompanied by altered cognitive performance.

  6. Short term effects of kinesiotaping on acromiohumeral distance in asymptomatic subjects: a randomised controlled trial.

    Science.gov (United States)

    Luque-Suarez, A; Navarro-Ledesma, S; Petocz, P; Hancock, M J; Hush, J

    2013-12-01

    The first aim of this study was to investigate whether kinesiotaping (KT) can increase the acromiohumeral distance (AHD) in asymptomatic subjects in the short term. The second aim was to investigate whether the direction of kinesiotaping application influences AHD. In recent years, the use of KT has become increasingly popular for a range of musculoskeletal conditions and for sport injuries. To date, we are unaware of any research investigating the effect of kinesiotaping on AHD. Moreover, it is unknown whether the direction of kinesiotaping application for the shoulder is important. Forty nine participants were randomly assigned to one of three groups: kinesiotaping group 1 (KT1), kinesiotaping group 2 (KT2) and sham kinesiotaping (KT3). AHD ultrasound measurements at 0° and 60° of shoulder elevation were collected at baseline and immediately after kinesiotape application. The results showed significant improvements in AHD after kinesiotaping, compared with sham taping. The mean difference in AHD between KT1 and KT3 groups was 1.28 mm (95% CI: 0.55, 2.03), and between KT2 and KT3 was 0.98 mm (95% CI: 0.23, 1.74). Comparison of KT1 and KT2 groups, which was performed to identify whether the direction of taping influences the AHD, indicated there were no significant differences. KT increases AHD in healthy individuals immediately following application, compared with sham kinesiotape. No differences were found with respect to the direction in which KT was applied. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Musculoskeletal Pain in High-G Aircraft Training Programs: A Survey of Student and Instructor Pilots

    Science.gov (United States)

    2016-06-01

    not addressed early, due to stigmas of reporting and lack of availability of effective therapies, are resulting in chronic long-term disabilities ...symptoms in pilots flying high-G aircraft, impacting mission readiness with concerns for chronic disability . We hypothesized similar prevalence of MS...will result in chronic disabilities . 15. SUBJECT TERMS Musculoskeletal pain, student pilots, instructor pilots, high-G aircraft, OMT, DNIF 16

  8. Development of a Flammability Test Method for Aircraft Blankets

    Science.gov (United States)

    1996-03-01

    Flammability testing of aircraft blankets was conducted in order to develop a fire performance test method and performance criteria for blankets supplied to commercial aircraft operators. Aircraft blankets were subjected to vertical Bunsen burner tes...

  9. Aircraft systems design methodology and dispatch reliability prediction

    OpenAIRE

    Bineid, Mansour

    2005-01-01

    Aircraft despatch reliability was the main subject of this research in the wider content of aircraft reliability. The factors effecting dispatch reliability, aircraft delay, causes of aircraft delays, and aircraft delay costs and magnitudes were examined. Delay cost elements and aircraft delay scenarios were also studied. It concluded that aircraft dispatch reliability is affected by technical and non-technical factors, and that the former are under the designer's control. It showed that ...

  10. Short-Term Effects of Electroconvulsive Therapy on Subjective and Actigraphy-Assessed Sleep Parameters in Severely Depressed Inpatients

    Directory of Open Access Journals (Sweden)

    Alexander Hoogerhoud

    2015-01-01

    Full Text Available Background. Sleep disturbances are a key feature of major depression. Electroconvulsive treatment (ECT may improve polysomnography-assessed sleep characteristics, but its short-term effects on actigraphy-assessed and subjective sleep characteristics are unknown. We therefore aimed to assess the effects of ECT on subjective and objective sleep parameters in a proof-of-principle study. Methods. We assessed subjective and objective sleep parameters in 12 severely depressed patients up to 5 consecutive days during their ECT course, corresponding to a total of 43 nights (including 19 ECT sessions. The 12 patients were 83% female and on average 62 (standard deviation (SD 14 years old and had an average MADRS score of 40 at baseline (SD 21. Results. Subjective and objective sleep parameters were not directly affected by ECT. The subjective sleep efficiency parameter was similar on the day after ECT and other days. ECT did not affect the number of errors in the Sustained Attention to Response Task. Patients subjectively underestimated their total sleep time by 1.4 hours (P<0.001 compared to actigraphy-assessed sleep duration. Conclusion. ECT did not affect subjective and actigraphy-assessed sleep in the short term. Depressed patients profoundly underestimated their sleep duration.

  11. Acute, subacute and long-term subjective effects of psilocybin in healthy humans: a pooled analysis of experimental studies.

    Science.gov (United States)

    Studerus, Erich; Kometer, Michael; Hasler, Felix; Vollenweider, Franz X

    2011-11-01

    Psilocybin and related hallucinogenic compounds are increasingly used in human research. However, due to limited information about potential subjective side effects, the controlled medical use of these compounds has remained controversial. We therefore analysed acute, short- and long-term subjective effects of psilocybin in healthy humans by pooling raw data from eight double-blind placebo-controlled experimental studies conducted between 1999 and 2008. The analysis included 110 healthy subjects who had received 1-4 oral doses of psilocybin (45-315 µg/kg body weight). Although psilocybin dose-dependently induced profound changes in mood, perception, thought and self-experience, most subjects described the experience as pleasurable, enriching and non-threatening. Acute adverse drug reactions, characterized by strong dysphoria and/or anxiety/panic, occurred only in the two highest dose conditions in a relatively small proportion of subjects. All acute adverse drug reactions were successfully managed by providing interpersonal support and did not need psychopharmacological intervention. Follow-up questionnaires indicated no subsequent drug abuse, persisting perception disorders, prolonged psychosis or other long-term impairment of functioning in any of our subjects. The results suggest that the administration of moderate doses of psilocybin to healthy, high-functioning and well-prepared subjects in the context of a carefully monitored research environment is associated with an acceptable level of risk.

  12. Runway Detection From Map, Video and Aircraft Navigational Data

    Science.gov (United States)

    2016-03-01

    are corrected using image-processing techniques, such as the Hough transform for linear features. 14. SUBJECT TERMS runway, map, aircraft...video, detection, rotation matrix, Hough transform. 15. NUMBER OF PAGES 87 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT Unclassified 18...as the Hough transform for linear features. vi THIS PAGE INTENTIONALLY LEFT BLANK vii TABLE OF CONTENTS I. INTRODUCTION

  13. Subject-Verb Agreement and Verbal Short-Term Memory: A Perspective from Greek Children with Specific Language Impairment

    Science.gov (United States)

    Lalioti, Marina; Stavrakaki, Stavroula; Manouilidou, Christina; Talli, Ioanna

    2016-01-01

    This study investigated the performance of school age Greek-speaking children with SLI on verbal short-term memory (VSTM) and Subject-Verb (S-V) agreement in comparison to chronological age controls and younger typically developing children. VSTM abilities were assessed by means of a non-word repetition task (NRT) and an elicited production task,…

  14. The long-term effects of chronic recreational ketamine use on cognition and subjective experiences

    OpenAIRE

    Grayer, J. P.

    2007-01-01

    Rationale: A review of the chronic recreational ketamine research is needed because of (i) increases in recreational ketamine use in the past five years, and (ii) its application to the N-Methyl-D-Aspartate-Receptor ('NMDA-R') hypofunction model of psychosis.;Method: PsychInfo and Pubmed databases were searched using the following terms: 'ketamine', 'frequent', 'regular*, 'repeated', 'chronic', and 'long-term'. The search was limited to human populations and English language journals. Relevan...

  15. Global Judgments of Subjective Well-Being: Situational Variability and Long-Term Stability

    Science.gov (United States)

    Eid, Michael; Diener, Ed

    2004-01-01

    Subjective well-being (SWB) is an important indicator of quality of life. SWB can be conceptualized as a momentary state (e.g., mood) as well as a relatively stable trait (e.g., life satisfaction). The validity of self-reported trait aspects of SWB has been questioned by experimental studies showing that SWB judgments seem to be strongly context…

  16. Dyslipidemia in HIV-1 Infected Subjects with Short Term Usage of ...

    African Journals Online (AJOL)

    Michaelis

    ultimately leads to gluconeogenesis, hyperinsulinaemia, insulin resistance, increased fat synthesis as well as, fatty liver development and weight gain are biochemical abnormalities that can directly alter liver enzymes and lipid profiles in HAART using. HIV subjects. Occurrence of mitochondrial dysfunction is listed as part of ...

  17. The difference in subjective and objective complexity in the visual short-term memory

    DEFF Research Database (Denmark)

    Dall, Jonas Olsen; Sørensen, Thomas Alrik

    Several studies discuss the influence of complexity on the visual short term memory; some have demonstrated that short-term memory is surprisingly stable regardless of content (e.g. Luck & Vogel, 1997) where others have shown that memory can be influenced by the complexity of stimulus (e.g. Alvarez...... of expertise (e.g. Dall, et al., 2016). We will present a paradigm testing the proposed distinction using specific isolation of attentional components (see Bundesen, 1990; Sørensen, Vangkilde, & Bundesen, 2015). We propose that objective complexity can be manipulated through the number of strokes in Chinese...

  18. Important prognostic factors for the long-term survival of lung cancer subjects in Taiwan

    Directory of Open Access Journals (Sweden)

    Ko Albert

    2008-11-01

    Full Text Available Abstract Background This study used a large-scale cancer database in determination of prognostic factors for the survival of lung cancer subjects in Taiwan. Methods Total of 24,910 subjects diagnosed with lung cancer was analysed. Survival estimates by Kaplan-Meier methods. Cox proportional-hazards model estimated the death risk (hazard ratio (HR for various prognostic factors. Results The prognostic indicators associated with a higher risk of lung cancer deaths are male gender (males versus females; HR = 1.07, 95% confidence intervals (CI: 1.03–1.11, males diagnosed in later periods (shown in 1991–1994 versus 1987–1990; HR = 1.13, older age at diagnosis, large cell carcinoma (LCC/small cell carcinoma (SCC, and supportive care therapy over chemotherapy. The overall 5-year survival rate for lung cancer death was significantly poorer for males (21.3% than females (23.6%. Subjects with squamous cell carcinoma (SQCC and treatment by surgical resection alone had better prognosis. We find surgical resections to markedly increase 5-year survival rate from LCC, decreased risk of death from LCC, and no improved survival from SCC. Conclusion Gender and clinical characteristics (i.e. diagnostic period, diagnostic age, histological type and treatment modality play important roles in determining lung cancer survival.

  19. The salivary microbiome is consistent between subjects and resistant to impacts of short-term hospitalization.

    Science.gov (United States)

    Cabral, Damien J; Wurster, Jenna I; Flokas, Myrto E; Alevizakos, Michail; Zabat, Michelle; Korry, Benjamin J; Rowan, Aislinn D; Sano, William H; Andreatos, Nikolaos; Ducharme, R Bobby; Chan, Philip A; Mylonakis, Eleftherios; Fuchs, Beth Burgwyn; Belenky, Peter

    2017-09-08

    In recent years, a growing amount of research has begun to focus on the oral microbiome due to its links with health and systemic disease. The oral microbiome has numerous advantages that make it particularly useful for clinical studies, including non-invasive collection, temporal stability, and lower complexity relative to other niches, such as the gut. Despite recent discoveries made in this area, it is unknown how the oral microbiome responds to short-term hospitalization. Previous studies have demonstrated that the gut microbiome is extremely sensitive to short-term hospitalization and that these changes are associated with significant morbidity and mortality. Here, we present a comprehensive pipeline for reliable bedside collection, sequencing, and analysis of the human salivary microbiome. We also develop a novel oral-specific mock community for pipeline validation. Using our methodology, we analyzed the salivary microbiomes of patients before and during hospitalization or azithromycin treatment to profile impacts on this community. Our findings indicate that azithromycin alters the diversity and taxonomic composition of the salivary microbiome; however, we also found that short-term hospitalization does not impact the richness or structure of this community, suggesting that the oral cavity may be less susceptible to dysbiosis during short-term hospitalization.

  20. A short-term high fat diet increases exposure to midazolam and omeprazole in healthy subjects

    NARCIS (Netherlands)

    Achterbergh, Roos; Lammers, Laureen A.; van Nierop, Samuel; Klümpen, Heinz-Josef; Soeters, Maarten R.; Mathôt, Ron A. A.; Romijn, Johannes A.

    2016-01-01

    Knowledge of factors contributing to variation in drug metabolism is of vital importance to optimize drug treatment. This study assesses the effects of a short-term hypercaloric high fat diet on metabolism of five oral drugs, which are each specific for a single P450 isoform: midazolam (CYP3A4),

  1. Recent onmiddellijk geheugenonderzoek bij zwakzinnigen [Investigation of short term memory in mentally retarded subjects

    NARCIS (Netherlands)

    Bunt, A.A.

    1975-01-01

    The aim of this literature review is to get a preliminary answer to the problem of the type of information processing deficit of undifferentiated retardates (with an IQ of about 70). Taking the topic of verbal short-term memory as a framework, it appears that children or adults of a subnormal

  2. Development of a Probabilistic Safety Assessment Framework for an Interim Dry Storage Facility Subjected to an Aircraft Crash Using Best-Estimate Structural Analysis

    Directory of Open Access Journals (Sweden)

    Belal Almomani

    2017-03-01

    Full Text Available Using a probabilistic safety assessment, a risk evaluation framework for an aircraft crash into an interim spent fuel storage facility is presented. Damage evaluation of a detailed generic cask model in a simplified building structure under an aircraft impact is discussed through a numerical structural analysis and an analytical fragility assessment. Sequences of the impact scenario are shown in a developed event tree, with uncertainties considered in the impact analysis and failure probabilities calculated. To evaluate the influence of parameters relevant to design safety, risks are estimated for three specification levels of cask and storage facility structures. The proposed assessment procedure includes the determination of the loading parameters, reference impact scenario, structural response analyses of facility walls, cask containment, and fuel assemblies, and a radiological consequence analysis with dose–risk estimation. The risk results for the proposed scenario in this study are expected to be small relative to those of design basis accidents for best-estimated conservative values. The importance of this framework is seen in its flexibility to evaluate the capability of the facility to withstand an aircraft impact and in its ability to anticipate potential realistic risks; the framework also provides insight into epistemic uncertainty in the available data and into the sensitivity of the design parameters for future research.

  3. Long-term effectiveness of unboosted atazanavir plus abacavir/lamivudine in subjects with virological suppression

    DEFF Research Database (Denmark)

    Llibre, Josep M; Cozzi-Lepri, Alessandro; Pedersen, Court

    2016-01-01

    VL), performing a time to loss of virological response (TLOVR Virological failure (VF) was defined as confirmed pVL >50 copies/mL.We included 285 subjects, 67% male, with median baseline CD4 530 cells, and 44 months with pVL ≤50 copies/mL. The third...... drug in the previous regimen was ritonavir-boosted atazanavir (ATV/r) in 79 (28%), and another ritonavir-boosted protease inhibitor (PI/r) in 29 (10%). Ninety (32%) had previously failed with a PI. Proportions of people with virological success at 48/96/144 weeks were 90%/87%/88% (TLOVR) and 74...

  4. Interaction between mode of learning and subjective experience: translation effects in long-term memory.

    Science.gov (United States)

    Rackie, James M; Brandt, Karen R; Eysenck, Michael W

    2015-01-01

    It has been suggested that writing auditorily presented words at encoding involves distinctive translation processes between visual and auditory domains, leading to the formation of distinctive memory traces at retrieval. This translation effect leads to higher levels of recognition than the writing of visually presented words, a non-translation effect. The present research investigated whether writing and the other translation effect of vocalisation (vocalising visually presented words) would be present in tests of recall, recognition memory and whether these effects are based on the subjective experience of remembering or knowing. Experiment 1 found a translation effect in the auditory domain in recall, as the translation effect of writing yielded higher recall than both non-translation effects of vocalisation and silently hearing. Experiment 2 found a translation effect in the visual domain in recognition, as the translation effect of vocalisation yielded higher recognition than both non-translation effects of writing and silently reading. This translation effect was attributable to the subjective experience of remembering rather than knowing. The present research therefore demonstrates the beneficial effect of translation in both recall and recognition, with the effect of vocalisation in recognition being based on rich episodic remembering.

  5. Effects of pregabalin on subjective sleep disturbance symptoms during withdrawal from long-term benzodiazepine use.

    Science.gov (United States)

    Rubio, Gabriel; Bobes, Julio; Cervera, Gaspar; Terán, Antonio; Pérez, María; López-Gómez, Vanessa; Rejas, Javier

    2011-01-01

    To evaluate the effectiveness of pregabalin as a tapering therapy on the subjective sleep quality of patients who underwent a benzodiazepine withdrawal program in routine medical practice. Secondary analysis of a 12-week prospective, open noncontrolled study carried out in patients who met DSM-IV-TR criteria for benzodiazepine dependence. Sleep was evaluated with the Medical Outcomes Study Sleep Scale (MOS Sleep Scale). 282 patients were included in the analysis. Mean (±SD) pregabalin dose was 315 ± 166 mg/day at the end of the trial. We observed a significant and clinically relevant improvement in sleep outcomes at the endpoint, with a total score reduction from 55.8 ± 18.9 to 25.1 ± 18.0 at week 12 (i.e. a 55% reduction). Similar findings were apparent using the six dimensions of the MOS Sleep Scale. Moderate correlations were observed between the MOS Sleep summary index and sleep domains, and there were improvements in anxiety symptoms and disease severity. These findings suggest that pregabalin may improve subjective sleep quality in patients who underwent a benzodiazepine withdrawal program. This effect appears to be partly independent of improvements in symptoms of anxiety or withdrawal. However, controlled studies are needed to establish the magnitude of the effect of pregabalin. Copyright © 2011 S. Karger AG, Basel.

  6. Redox proteomics and physiological responses in Cistus albidus shrubs subjected to long-term summer drought followed by recovery

    OpenAIRE

    Brossa, Ricard; Pint?-Marijuan, Marta; Francisco, Rita; L?pez-Carbonell, Marta; Chaves, Maria Manuela; Alegre, Leonor

    2014-01-01

    Main conclusion The interaction between enzymatic and non-enzymatic antioxidants, endogenous levels of ABA and ABA-GE, the rapid recuperation of photosynthetic proteins under re-watering as well the high level of antioxidant proteins in previously drought-stressed plants under re-watering conditions, will contribute to drought resistance in plants subjected to a long-term drought stress under Mediterranean field conditions. This work provides an overview of the mechanisms of Cistus albidus ac...

  7. Gut microbiome response to short-term dietary interventions in reactive hypoglycemia subjects.

    Science.gov (United States)

    Quercia, Sara; Turroni, Silvia; Fiori, Jessica; Soverini, Matteo; Rampelli, Simone; Biagi, Elena; Castagnetti, Andrea; Consolandi, Clarissa; Severgnini, Marco; Pianesi, Mario; Fallucca, Francesco; Pozzilli, Paolo; Brigidi, Patrizia; Candela, Marco

    2017-11-01

    Reactive hypoglycemia is a metabolic disorder that provokes severe hypoglycemic episodes after meals. Over recent years, the gut microbiota has been recognized as potential target for the control of metabolic diseases, and the possibility to correct gut microbiota dysbioses through diet, favouring the recovery of metabolic homeostasis, has been considered. We investigate the impact of 2 short-term (3-day) nutritional interventions, based on the macrobiotic Ma-Pi 2 diet and a control Mediterranean diet, on the structure and functionality of the gut microbiota in 12 patients affected by reactive hypoglycemia. The gut microbiota composition was characterized by next-generation sequencing of the V3 to V4 region of the 16S rRNA gene, and the ecosystem functionality was addressed by measuring the faecal concentration of short-chain fatty acids (SCFAs). In order to measure the short-term physiological gut microbiota fluctuation, the microbiomes of 7 healthy people were characterized before and after 3 days of constant diet. While no convergence of the gut microbiota compositional profiles was observed, a significant increase in SCFA faecal levels was induced only in the Ma-Pi 2 diet group, suggesting the potential of this diet to support a short-term functional convergence of the gut microbiota, regardless of the individual compositional layout. The Ma-Pi 2 diet, with its high fibre load, was effective in increasing the production of SCFAs by the gut microbiota. Because these metabolites are known for their ability to counterbalance the metabolic deregulation in persons with glucose impairment disorders, their increased bioavailability could be of some relevance in reactive hypoglycemia. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Long-term Denitrification Processes and Kinetics in a Crystalline Aquifer subject to Pumping from 1991

    Science.gov (United States)

    Roques, Clement; Aquilina, Luc; Vergnaud-Ayraud, Virginie; Boisson, Alexandre; Labasque, Thierry; Longuevergne, Laurent; Ben Maamar, Sarah; Dufresne, Alexis; Bour, Olivier

    2017-04-01

    The kinetic of denitrification associated to long-term mixing processes in heterogeneous aquifers is particularly challenging to constrain. Specifically, chemical evolutions related to groundwater exploitation are cases that are poorly known. It remains particularly unclear if long-term pumping whether enhances or slows-down the nitrate reducing processes and what is the source of electron donor sustaining the reaction. The aim of this study is to investigate the dynamic of denitrification processes induced by long-term pumping in the Ploemeur aquifer (Britany, France) which has been operated for water supply since 1991. Several batch experiments have been carried out in order to fully characterize the kinetics of the denitrification reaction involved. Batches consisted in crushed rock: more or less weathered granite and schists, and water sampled from the site. Denitrification always developed except in sterilized batchs. Denitrification rate was independent on the rock type but more on the state of the bacterial community. Inorganic dissolved carbon only showed moderate variations while organic carbon remained at low concentrations. Both observations make heterotrophic denitrification unlikely. A silicate dissolution was observed and detailed analysis of the cations quantified a main biotite contribution. The iron produced by biotite dissolution accounts for the denitrification processes observed. Long term time-series analysis of the conservative elements recorded at the pumped well were used to determine mixing fractions from different compartments of the aquifer based on a Principal Component Analysis approach coupled with an end-member mixing analysis. Discharge fractions were then used to quantify the denitrification kinetic linked to pumping. With increasing concentration of Nitrate entering in the groundwater system since the beginning of the operations, computations confirm that i) autotrophic denitrification processes are dominant and ii) biotite plays a

  9. A short-term high fat diet increases exposure to midazolam and omeprazole in healthy subjects.

    Science.gov (United States)

    Achterbergh, Roos; Lammers, Laureen A; van Nierop, Samuel; Klümpen, Heinz-Josef; Soeters, Maarten R; Mathôt, Ron A A; Romijn, Johannes A

    2016-07-01

    Knowledge of factors contributing to variation in drug metabolism is of vital importance to optimize drug treatment. This study assesses the effects of a short-term hypercaloric high fat diet on metabolism of five oral drugs, which are each specific for a single P450 isoform: midazolam (CYP3A4), omeprazole (CYP2C19), metoprolol (CYP2D6), S-warfarin (CYP2C9) and caffeine (CYP1A2). In 9 healthy volunteers, pharmacokinetics of the five drugs were assessed after an overnight fast at two separate occasions: after a regular diet and after 3 days of a hypercaloric high fat diet (i.e. regular diet supplemented with 500 mL cream [1715 kcal, 35% fat]). Pharmacokinetic parameters (mean [SEM]) were estimated by non-compartmental analysis. The high fat diet increased exposure to midazolam by 19% from 24.7 (2.6) to 29.5 (3.6) ng ml-1h-1 (p=0.04) and exposure to omeprazole by 31% from 726 (104) to 951 (168) ng ml-1h-1 (p=0.05). Exposure to metoprolol, caffeine and S-warfarin was not affected by the high fat diet. A short-term hypercaloric high fat diet increases exposure to midazolam and omeprazole, possibly reflecting modulation of CYP3A4 and CYP2C19.

  10. CARIBIC passenger aircraft measurements in the UT/LMS: Long-term analysis of the correlation between acetone and carbon monoxide

    Science.gov (United States)

    Fischbeck, Garlich; Neumaier, Marco; Ferreira de Brito, Joel; Slemr, Franz; Brenninkmeijer, Carl A. M.; Zahn, Andreas

    2013-04-01

    Since May 2005 the CARIBIC flying laboratory is regularly deployed in the cargo bay of a Lufthansa passenger aircraft (Airbus A340-600) measuring ~100 trace gases and aerosol components in the upper troposphere / lowermost stratosphere UT/LMS on four flights per month. Acetone is measured using a PTR-MS (proton-transfer-reaction mass spectrometer) and carbon monoxide (CO) is detected using a fast-response vacuum UV resonance fluorescence instrument. Over the years a comprehensive dataset of accurate and high-resolution acetone and carbon monoxide concentrations has been composed. Acetone is directly emitted both from anthropogenic and biogenic sources or can be produced by the oxidation of hydrocarbons (e.g. propane). CO is produced by incomplete combustion of hydrocarbons (e.g. methane or petrol) and is considered to be a reliable tracer for anthropogenic air pollution and biomass burning. Furthermore it is often co-emitted with hydrocarbons that are important precursors of acetone (i.e. propane). A strong linear correlation between acetone and CO was found during research aircraft campaigns (Reus et. al. 2003). However the available dataset from research aircraft is very limited. We present a data analysis based on CARIBIC in-situ data of acetone and CO collected over ~6 years. Ozone data were used to distinguish between tropospheric and stratospheric air masses. Due to possibly large differences between the sampled latitude and the origin of the sampled air masses 5-day back-trajectories from the ECMWF model were utilized for data interpretation. Overall, the variability in the acetone-CO correlation slope is considerable, which indicates that a representative long-term dataset as collected during CARIBIC is required to obtain representative mean slopes. In winter substantially lower acetone-CO correlation slopes were observed as during summer times. Slopes grouped according to the 5-day back trajectories showed an increase with latitude from (summer / winter

  11. Change in hydraulic traits of Mediterranean Quercus ilex subjected to long-term throughfall exclusion.

    Science.gov (United States)

    Limousin, Jean-Marc; Longepierre, Damien; Huc, Roland; Rambal, Serge

    2010-08-01

    Mediterranean tree species experience unpredictable climate environments and severe summer droughts and they may be impaired by the trend of decline in precipitation projected as a consequence of global climate change. The response of Quercus ilex to drought was studied by measuring hydraulic traits of trees growing in a mature forest subjected to partial throughfall exclusion for 6 years. We measured hydraulic conductivity, xylem vulnerability to embolism, and anatomical features in branches and roots. Xylem vulnerability to embolism was higher in the dry treatment than in the control treatment, P₅₀ of branches was on average -3.88 +/- 0.80 MPa for the control treatment compared with -3.41 +/- 0.80 MPa for the dry treatment, but the difference was not statistically significant. A similar difference between treatments was observed for roots, which exhibited lower P₅₀ values. This change of xylem vulnerability to embolism was not linked to modification of the hydraulic conductivity or vessel anatomy, which remained unaffected by the throughfall exclusion treatment. The xylem density of branches was lower in the dry treatment. The hydraulic conductivity was correlated with the mean vessel diameter of xylem, but the P₅₀ was not. The main response of trees from the dry treatment to reduced water availability appeared to be a reduction in the transpiring leaf area, which resulted in significantly increased leaf-specific conductivity.

  12. Short-term triglyceride lowering with fenofibrate improves vasodilator function in subjects with hypertriglyceridemia.

    Science.gov (United States)

    Capell, Warren H; DeSouza, Christopher A; Poirier, Paul; Bell, Melanie L; Stauffer, Brian L; Weil, Kathleen M; Hernandez, Teri L; Eckel, Robert H

    2003-02-01

    The objective of this study was to investigate the effects of lowering plasma triglycerides (TGs) on endothelial function and gain insight into the role played by free fatty acids (FFAs) in hypertriglyceridemia-associated vascular dysfunction. Eleven hypertriglyceridemic subjects without coronary artery disease, diabetes, elevated low-density lipoprotein cholesterol, tobacco use, or hypertension were studied using a randomized, double-blinded, crossover design (fenofibrate and placebo, 14 days). After each regimen, forearm blood flow was assessed by plethysmography in response to arterial acetylcholine, nitroprusside, and verapamil infusion. Hourly plasma TGs, FFA, glucose, and insulin were measured during a 24-hour feeding cycle to characterize the metabolic environment. Changes in plasma FFA after intravenous heparin were used to estimate typical FFA accumulation in the luminal endothelial microenvironment. Fenofibrate lowered plasma TG (P<0.001), total cholesterol (P<0.01), and apolipoprotein B (P<0.01) without altering high-density lipoprotein or low-density lipoprotein cholesterol concentrations. Forearm blood flow in response to acetylcholine (P<0.0001), nitroprusside (P<0.001), and verapamil (P<0.0001) improved after fenofibrate. Fenofibrate lowered 24-hour (P<0.0001) and post-heparin (P<0.001) TG and tended to lower 24-hour (P=0.054) and post-heparin (P=0.028) FFA. Vascular smooth muscle function significantly improves after lowering plasma TG without changes in confounding lipoproteins or insulin resistance. The data raise additional questions regarding the role of FFA in hypertriglyceridemia-associated vascular dysfunction.

  13. Short-Term Effect of Gabapentin on Subjective Tinnitus in Acoustic Trauma Patients

    Directory of Open Access Journals (Sweden)

    Ali Goljanian Tabrizi

    2017-03-01

    Full Text Available Introduction:Although several treatment approaches have been proposed for tinnitus, there are currently no Food and Drug Administration (FDA-approved agents available to treat this condition. In this study, we evaluated the effect of gabapentin on the sensation of subjective tinnitus in patients with acoustic trauma referring to the ear, nose and throat (ENT clinic of Taleghani Hospital during 2014. Materials and Methods:In this double-blind, randomized clinical trial, 103 patients with tinnitus due to acoustic trauma who were referred to the ENT clinic of Taleghani Hospital during 2014 were randomized to the gabapentin (300 mg bid, n=55 or control (n=48 groups. The two groups were then compared before and after 6 weeks of treatment using a visual analog scale (VAS. At least a 30% reduction in VAS was considered a response to treatment. Results:Differences between the two groups regarding sex, age, duration of disease, and audiometry results was not significant (P>0.05. After 6 weeks’ treatment, the VAS significantly decreased in both groups (P

  14. Subjective socioeconomic status as a predictor of long-term care staff burnout and positive caregiving experiences.

    Science.gov (United States)

    Ayalon, Liat

    2008-06-01

    The potentially negative consequences associated with providing care to older adults are well documented. Recently, there has been an increasing interest in the positive aspects associated with caregiving. Both aspects are believed to represent a continuum of caregiving experiences. Long-term care (LTC) staff members often report high levels of burnout associated with their work. Whereas several job characteristics and objective indicators of socioeconomic status have been identified as potential predictors of LTC staff caregiving experiences, the role of subjective socioeconomic status (i.e. one's view of one's place in society) has not yet been evaluated. A cross-sectional design of 122 LTC staff members. LTC staff completed the Maslach Burnout Inventory and the Positive Aspects of Caregiving questionnaire. They also completed questions about job characteristics (i.e. staff-to-resident ratio, number of hours worked per day, and years of experience working with older adults), objective sociodemographic variables (i.e. level of education, professional affiliation), and subjective socioeconomic indicator (i.e. MacArthur Scale of Subjective Social Status). Hierarchical regression analyses were conducted to identify the unique contribution of job characteristics, objective socioeconomic status, and subjective socioeconomic status to LTC staff caregiving experiences. Subjective socioeconomic status remained a significant predictor of LTC staff experience even once job characteristics and objective indicators of socioeconomic status were entered into the model. Those who placed themselves higher on the subjective social ladder reported higher levels of positive caregiving experiences and lower levels of burnout. Building a sense of community identity and improving one's status within the community might result in lower levels of burnout and better caregiving experiences among LTC staff.

  15. Long-term effect of bariatric surgery on liver enzymes in the Swedish Obese Subjects (SOS study.

    Directory of Open Access Journals (Sweden)

    Maria Antonella Burza

    Full Text Available BACKGROUND AND AIM: Obesity is associated with elevated serum transaminase levels and non-alcoholic fatty liver disease and weight loss is a recommended therapeutic strategy. Bariatric surgery is effective in obtaining and maintaining weight loss. Aim of the present study was to examine the long-term effects of bariatric surgery on transaminase levels in obese individuals. METHODS: The Swedish Obese Subjects (SOS study is a prospective controlled intervention study designed to compare the long-term effects of bariatric surgery and usual care in obese subjects. A total of 3,570 obese participants with no excess of alcohol consumption at baseline (1,795 and 1,775 in the control and surgery group, respectively were included in the analyses. Changes in transaminase levels during follow-up were compared in the surgery and control groups. RESULTS: Compared to usual care, bariatric surgery was associated with lower serum ALT and AST levels at 2- and 10- year follow up. The reduction in ALT levels was proportional to the degree of weight loss. Both the incidence of and the remission from high transaminase levels were more favorable in the surgery group compared to the control group. Similarly, the prevalence of ALT/AST ratio <1 was lower in the surgery compared to the control group at both 2- and 10-year follow up. CONCLUSIONS: Bariatric surgery results in a sustained reduction in transaminase levels and a long-term benefit in obese individuals.

  16. SHORT TERM EFFECT OF ACUPUNCTURE-TENS ON LUNG FUNCTIONS AND DYSPNEA FOR SUBJECTS WITH MODERATE COPD

    Directory of Open Access Journals (Sweden)

    Vinod Babu. K

    2015-10-01

    Full Text Available Background: Acupuncture TENS is used to improve pain instead of invasive acupuncture. Acupuncture shown to improve dyspnoea and lung functions in COPD (Chronic Obstructive Pulmonary Disease patients. The purpose of the study is to determine Short term effectiveness of Acupuncture-TENS in reducing dyspnea and improving lung functions for subjects with moderate COPD. Method: An experimental study design, selected 30 geriatric subjects with COPD randomized 15 subjects into each Study and Control group. Study group received Acu-TENS for 45 minutes for total 5 sessions, while control group received placebo TENS. Outcome measurements such as breathlessness using Modified Borg Scale (MBS, Lung functions using Pulmonary Function Test (PFT was measured before and after intervention. Results: Analysis from pre-intervention to post-intervention within study group found that there is statistically significant change in means of MBS, FEV1, FEV1/FVC ratio and within control group there is a statistically significant change in means of MBS, but there is no statistically significant change in means of FEV1, FVC and FEV1/FVC ratio. When post-intervention means were compared between the groups there is no statistically significant difference in means of MBS and FEV1, FVC and FEV1/FVC ratio. Conclusion: It is concluded that one week of Acu-TENS on EXL1 point found no significant effect on improving dyspnea and lung functions in subjects with moderate COPD in geriatric populations.

  17. Moderate- to long-term periodontal outcomes of subjects failing to complete a course of periodontal therapy.

    Science.gov (United States)

    Goh, V; Hackmack, P P; Corbet, E F; Leung, W K

    2017-06-01

    The current retrospective cross-sectional study investigated 5-18-year treatment outcomes in subjects who did not complete a recommended course of periodontal therapy. Sixty-five subjects who voluntarily discontinued therapy were recalled. The subjects' demographic data and dental history since discontinuation of periodontal treatment were collected via questionnaires. The subjects' periodontal condition, radiographic data and individual tooth-based prognosis at pre-discontinuation and recall were compared. A total of 229 teeth had been lost over time, mainly due to periodontal reasons. Upper and lower molars were most frequently lost. Rate of tooth loss (0.38/patient per year) was comparable to untreated patients. Deterioration in periodontal health in terms of increased percentage of sites with bleeding on probing (BOP) and sites with probing pocket depths (PPD) of 6 mm or more at re-examination was observed. Positive correlations were found between tooth loss and: (i) years since therapy discontinued; (ii) percentage of sites with PPD of 6 mm or more at pre-discontinuation; and (iii) at re-examination. Percentage of sites with PPD of 6 mm or more at recall was positively correlated with periodontal tooth loss and negatively correlated with percentage of sites without BOP. Patients not completing a course of periodontal therapy are at risk of further tooth loss and deterioration in periodontal conditions over time. © 2016 Australian Dental Association.

  18. Impaired basal glucose effectiveness but unaltered fasting glucose release and gluconeogenesis during short-term hypercortisolemia in healthy subjects

    DEFF Research Database (Denmark)

    Nielsen, Michael F; Caumo, Andrea; Chandramouli, Visvanathan

    2004-01-01

    Excess cortisol has been demonstrated to impair hepatic and extrahepatic insulin action. To determine whether glucose effectiveness and, in terms of endogenous glucose release (EGR), gluconeogenesis, also are altered by hypercortisolemia, eight healthy subjects were studied after overnight infusion...... contribution of gluconeogenesis to EGR (P = 0.33) did not differ on the two study days. During the prandial glucose infusion, the integrated glycemic response above baseline was higher in the presence of hydrocortisone than during saline infusion (P .... In conclusion, short-term hypercortisolemia in healthy individuals with normal beta-cell function decreases insulin action but does not alter rates of EGR and gluconeogenesis. In addition, cortisol impairs the ability of glucose to suppress its own production, which due to accumulation of glucose in the glucose...

  19. Aircraft adaptive learning control

    Science.gov (United States)

    Lee, P. S. T.; Vanlandingham, H. F.

    1979-01-01

    The optimal control theory of stochastic linear systems is discussed in terms of the advantages of distributed-control systems, and the control of randomly-sampled systems. An optimal solution to longitudinal control is derived and applied to the F-8 DFBW aircraft. A randomly-sampled linear process model with additive process and noise is developed.

  20. Aircraft Disinsection

    Science.gov (United States)

    Some countries may require aircraft coming from countries where certain insects or insect-borne diseases are present, such as malaria and Zika virus, to be treated with insecticide. Find out about regulation of pesticides for this treatment.

  1. Amphibious Aircraft

    Data.gov (United States)

    National Aeronautics and Space Administration — A brief self composed research article on Amphibious Aircrafts discussing their use, origin and modern day applications along with their advantages and disadvantages...

  2. Assessing the Impact of Operational Constraints on the Near-Term Unmanned Aircraft System Traffic Management Supported Market

    Science.gov (United States)

    Vascik, Parker D.; Jung, Jaewoo

    2016-01-01

    An economic impact market analysis was conducted for 16 leading sectors of commercial Unmanned Aerial System (UAS) applications predicted to be enabled by 2020 through the NASA UAS Traffic Management (UTM) program. Subject matter experts from seven industries were interviewed to validate concept of operations (ConOps) and market adoption assumptions for each sector. The market analysis was used to estimate direct economic impacts for each sector including serviceable addressable market, capital investment, revenue recovery potential, and operations cost savings. The resultant economic picture distinguishes the agricultural, pipeline and railroad inspection, construction, and maritime sectors of the nascent commercial UAS industry as providing the highest potential economic value in the United States. Sensitivity studies characterized the variability of select UAS sectors economic value to key regulatory or UTM ConOps requirements such as weight, altitude, and flight over populated area constraints. Takeaways from the analysis inform the validation of UTM requirements, technologies and timetables from a commercial market need and value viewpoint. This work concluded in August 2015 and reflects the state of the UAS industry and market projections at that time.

  3. Effects of long-term soft contact lens wear on the corneal thickness and corneal epithelial thickness of myopic subjects.

    Science.gov (United States)

    Lei, Yulin; Zheng, Xiuyun; Hou, Jie; Xu, Baozeng; Mu, Guoying

    2015-03-01

    To perform safe and successful corneal refractive surgery on myopic patients, corneal thickness (CT) and corneal epithelial thickness (CET) must be accurately measured. Numerous individuals with myopia wear soft contact lenses (SCLs) for the correction of visual acuity but may subsequently undergo corneal refractive surgery. The aim of the present study was therefore to investigate the effects of long-term SCL wear on the CT and the CET of myopic subjects in order to guarantee the safety and accuracy of subsequent corneal refractive surgeries. Fifty-six subjects prepared to receive refractive surgery at Jinan Mingshui Eye Hospital (Zhangqiu, China) from April to July 2013 were included in the study. CT and CET were measured in subjects immediately following discontinued SCL wear (group I, 56 eyes), and subsequently following >two weeks of discontinued SCL wear (group II, 56 eyes). Ninety-four subjects with no history of corneal contact lens wear were enrolled as a control group. The CT and CET were measured at positions with a radius of 0.0‑1.0, 1.0-2.5 (divided into eight quadrants) and 2.5-3.0 mm (divided into eight quadrants) away from the corneal center using the RTVue-100 Fourier-domain anterior segment optical coherence tomography system. A significant decrease in the CT of the subjects in group II was observed, compared with that of group I and the control group (P<0.05). A significant decrease was observed in the CET of groups I and II compared with that of the control group (P<0.05). Following discontinuation of SCL wear, CET increased. However, the increased CET was unable to reach the normal range exhibited by the control group. Edema and thinning of the corneal stroma, as well as thinning of the corneal epithelium were observed in groups I and II. In conclusion, it was proposed that in clinical practice, for myopic patients following long-term SCL wear, CT and CET should be determined ≥ two weeks following discontinuation of SCL wear, once a stable

  4. Short- and long-term subjective medical treatment outcome of trauma surgery patients: the importance of physician empathy

    Directory of Open Access Journals (Sweden)

    Steinhausen S

    2014-09-01

    Full Text Available Simone Steinhausen,1 Oliver Ommen,2 Sunya-Lee Antoine,1 Thorsten Koehler,3 Holger Pfaff,4 Edmund Neugebauer11Institute for Research in Operative Medicine (IFOM, Witten/Herdecke University, Campus Cologne-Merheim, Germany; 2Federal Centre for Health Education (BZgA, Cologne, Germany; 3Institute for Applied Social Sciences (infas, Bonn, Germany; 4Institute for Medical Sociology, Health Services Research and Rehabilitation Science (IMVR, Faculty of Human Science and Faculty of Medicine, University of Cologne, Germany Purpose: To investigate accident casualties’ long-term subjective evaluation of treatment outcome 6 weeks and 12 months after discharge and its relation to the experienced surgeon’s empathy during hospital treatment after trauma in consideration of patient-, injury-, and health-related factors. The long-term results are compared to the 6-week follow-up outcomes.Patients and methods: Two hundred and seventeen surgery patients were surveyed at 6 weeks, and 206 patients at 12 months after discharge from the trauma surgical general ward. The subjective evaluation of medical treatment outcome was measured 6 weeks and 12 months after discharge with the respective scale from the Cologne Patient Questionnaire. Physician Empathy was assessed with the Consultation and Relational Empathy Measure. The correlation between physician empathy and control variables with the subjective evaluation of medical treatment outcome 12 months after discharge was identified by means of logistic regression analysis under control of sociodemographic and injury-related factors.Results: One hundred and thirty-six patients were included within the logistic regression analysis at the 12-month follow-up. Compared to the 6-week follow-up, the level of subjective evaluation of medical treatment outcome was slightly lower and the association with physician empathy was weaker. Compared to patients who rated the empathy of their surgeon lower than 31 points, patients

  5. HIGHER EDUCATIONAL INSTITUTION AS A SUBJECT OF ADAPTATION OF RURAL STUDENTS TO THE TERMS OF THE CITY

    Directory of Open Access Journals (Sweden)

    Alyona Aleksandrovna Antipova

    2014-11-01

    Full Text Available The article is devoted to the difficulties of adaptation of rural students to the various spheres of life of the modern city. These difficulties are considered as a field of activity of higher educational institution, acting as the subject of adaptation of students coming to study from rural areas to the terms of the city. The authors ' point of view on this issue is substantiated by the analysis of data of several sociological surveys conducted in various regions of theRussian Federation. Also the experience of assistance in adaptation of the Mordovia state University named after N. P. Ogarev of the city ofSaransk, which is the largest in the Republic of Mordovia University and which accommodates a large number of rural youth. The relevance and scientific novelty of research consists in allocation of areas of adaptation support of students from rural areas by the higher educational institution.

  6. Redox proteomics and physiological responses in Cistus albidus shrubs subjected to long-term summer drought followed by recovery.

    Science.gov (United States)

    Brossa, Ricard; Pintó-Marijuan, Marta; Francisco, Rita; López-Carbonell, Marta; Chaves, Maria Manuela; Alegre, Leonor

    2015-04-01

    The interaction between enzymatic and non-enzymatic antioxidants, endogenous levels of ABA and ABA-GE, the rapid recuperation of photosynthetic proteins under re-watering as well the high level of antioxidant proteins in previously drought-stressed plants under re-watering conditions, will contribute to drought resistance in plants subjected to a long-term drought stress under Mediterranean field conditions. This work provides an overview of the mechanisms of Cistus albidus acclimation to long-term summer drought followed by re-watering in Mediterranean field conditions. To better understand the molecular mechanisms of drought resistance in these plants, a proteomic study using 2-DE and MALDI-TOF/TOF MS/MS was performed on leaves from these shrubs. The analysis identified 57 differentially expressed proteins in water-stressed plants when contrasted to well watered. Water-stressed plants showed an increase, both qualitatively and quantitatively, in HSPs, and downregulation of photosynthesis and carbon metabolism enzymes. Under drought conditions, there was considerable upregulation of enzymes related to redox homeostasis, DHA reductase, Glyoxalase, SOD and isoflavone reductase. However, upregulation of catalase was not observed until after re-watering was carried out. Drought treatment caused an enhancement in antioxidant defense responses that can be modulated by ABA, and its catabolites, ABA-GE, as well as JA. Furthermore, quantification of protein carbonylation was shown to be a useful marker of the relationship between water and oxidative stress, and showed that there was only moderate oxidative stress in C. albidus plants subjected to water stress. After re-watering plants recovered although the levels of ABA-GE and antioxidant enzymes still remain higher than in well-watered plants. We expect that our results will provide new data on summer acclimation to drought stress in Mediterranean shrubs.

  7. Life satisfaction in subjects with long-term musculoskeletal pain in relation to pain intensity, pain distribution and coping.

    Science.gov (United States)

    Anke, Audny; Damsgård, Elin; Røe, Cecilie

    2013-03-01

    To investigate levels of life satisfaction in subjects with long-term musculoskeletal pain in relation to pain characteristics and coping. Cross-sectional study. A total of 232 (42%) respondents answered self--report questionnaires regarding life satisfaction, self-efficacy, sense of coherence, pain distribution and pain intensity at rest and during activity. Levels of life satisfaction and scores for sense of coherence were low. Pain intensity at rest was negatively correlated with global life satisfaction. This result was also obtained in multiple regression analyses together with the coping factors. The life satisfaction domains activities of daily living/contacts were negatively correlated with pain intensity during activity, and the domains work/economy were negatively correlated with pain distribution. Pain was not associated with satisfaction with family life, partner relationship or sexual life. Younger age, being married/cohabitant and being female were protective for some domains. Clinically meaningful subgroups with regard to adaptation were identified by cluster analysis, and the highest level of coping was found in the adaptive cluster with high life satisfaction/low pain intensity at rest. Long-term pain is related to low levels of life satisfaction, and pain intensity and distribution influence satisfaction in different domains. Pain intensity is negatively associated with coping. The results support efforts to reduce pain, together with strengthening active coping processes and addressing individual needs.

  8. Alternate Fuels for Use in Commercial Aircraft

    Science.gov (United States)

    Daggett, David L.; Hendricks, Robert C.; Walther, Rainer; Corporan, Edwin

    2008-01-01

    The engine and aircraft Research and Development (R&D) communities have been investigating alternative fueling in near-term, midterm, and far-term aircraft. A drop in jet fuel replacement, consisting of a kerosene (Jet-A) and synthetic fuel blend, will be possible for use in existing and near-term aircraft. Future midterm aircraft may use a biojet and synthetic fuel blend in ultra-efficient airplane designs. Future far-term engines and aircraft in 50-plus years may be specifically designed to use a low- or zero-carbon fuel. Synthetic jet fuels from coal, natural gas, or other hydrocarbon feedstocks are very similar in performance to conventional jet fuel, yet the additional CO2 produced during the manufacturing needs to be permanently sequestered. Biojet fuels need to be developed specifically for jet aircraft without displacing food production. Envisioned as midterm aircraft fuel, if the performance and cost liabilities can be overcome, biofuel blends with synthetic jet or Jet-A fuels have near-term potential in terms of global climatic concerns. Long-term solutions address dramatic emissions reductions through use of alternate aircraft fuels such as liquid hydrogen or liquid methane. Either of these new aircraft fuels will require an enormous change in infrastructure and thus engine and airplane design. Life-cycle environmental questions need to be addressed.

  9. Variation of aircraft noise annoyance

    Science.gov (United States)

    Dempsey, T. K.

    1980-01-01

    Laboratory and field studies were conducted to determine the basis for increased sensitivity of people to noise during aircraft noise studies. This change in sensitivity could be attributed to either a physiological time-of-day effect (i.e., a circadian rhythm) or simply to the total number of aircraft noise events experienced during a laboratory test period. In order to investigate the time-of-day factor, noise sensitivity measures were obtained from subjects at home with cassette tape recorders/headsets over a 24 hour period. The effect of number of aircraft noise events on noise sensitivity was investigated within a laboratory. In these tests, measures of sensitivity to noise were obtained from subjects before and after their exposure to varying numbers of aircraft noise events. The 24 hour data showed no evidence that noise sensitivity is physiologically cyclical. Consequently, these data can not explain annoyance response variation to aircraft noise tests conducted during the daytime. However, the number of aircraft noise events did influence the subject's noise sensitivity. This effect completely accounts for the systematic increase in noise sensitivity during a laboratory test period.

  10. Aircraft noise effects on sleep: Mechanisms, mitigation and research needs

    Directory of Open Access Journals (Sweden)

    Mathias Basner

    2010-01-01

    Full Text Available There is an ample number of laboratory and field studies which provide sufficient evidence that aircraft noise disturbs sleep and, depending on traffic volume and noise levels, may impair behavior and well-being during the day. Although clinical sleep disorders have been shown to be associated with increased risk of cardiovascular diseases, only little is known about the long-term effects of aircraft noise disturbed sleep on health. National and international laws and guidelines try to limit aircraft noise exposure facilitating active and passive noise control to prevent relevant sleep disturbances and its consequences. Adopting the harmonized indicator of the European Union Directive 2002/49/EC, the WHO Night Noise Guideline for Europe (NNG defines four Lnight , outside ranges associated with different risk levels of sleep disturbance and other health effects ( 55 dBA. Although traffic patterns differing in number and noise levels of events that lead to varying degrees of sleep disturbance may result in the same Lnight , simulations of nights with up to 200 aircraft noise events per night nicely corroborate expert opinion guidelines formulated in WHO′s NNG. In the future, large scale field studies on the effects of nocturnal (aircraft noise on sleep are needed. They should involve representative samples of the population including vulnerable groups like children and chronically ill subjects. Optimally, these studies are prospective in nature and examine the long-term consequences of noise-induced sleep disturbances. Furthermore, epidemiological case-control studies on the association of nocturnal (aircraft noise exposure and cardiovascular disease are needed. Despite the existing gaps in knowledge on long-term health effects, sufficient data are available for defining limit values, guidelines and protection concepts, which should be updated with the availability of new data.

  11. Brief Report: Conveying Subjective Experience in Conversation: Production of Mental State Terms and Personal Narratives in Individuals with High Functioning Autism

    Science.gov (United States)

    Bang, Janet; Burns, Jesse; Nadig, Aparna

    2013-01-01

    Mental state terms and personal narratives are conversational devices used to communicate subjective experience in conversation. Pre-adolescents with high-functioning autism (HFA, n = 20) were compared with language-matched typically-developing peers (TYP, n = 17) on production of mental state terms (i.e., perception, physiology, desire, emotion,…

  12. Cadmium concentrations in the testes, sperm, and spermatids of mice subjected to long-term cadmium chloride exposure.

    Science.gov (United States)

    Bench, G; Corzett, M H; Martinelli, R; Balhorn, R

    1999-01-01

    Exposures to cadmium have been reported to reduce male fertility and there are several hypotheses that suggest how reduced male fertility may result from incorporation of cadmium into sperm chromatin. The purpose of this study was to determine whether mice subjected to long-term intraperitoneal cadmium exposure incorporated cadmium into their sperm chromatin. Male mice were exposed to 0.1 mg/kg body weight cadmium in the form of CdCl2 via intraperitoneal injection once per week for 4, 10, 26, and 52 weeks and then sacrificed. The cadmium contents of the liver, testes, pooled sperm, and pooled spermatids from dosed and control animals were determined by atomic absorption spectroscopy. Cadmium and zinc contents in individual sperm and spermatid heads were determined by particle-induced x-ray emission. Atomic absorption spectroscopy revealed that although cadmium accumulated in the liver and testes, cadmium was not detected in pooled sperm or spermatid samples down to minimum detectable limits of 0.02 microg/g dry weight. Particle-induced x-ray emission analyses did not show the presence of cadmium in any sperm or spermatid head down to minimum detectable limits of 15 microg/g dry weight. Particle-induced x-ray emission analyses also demonstrated that phosphorus, sulfur, and zinc concentrations in individual sperm and spermatid heads were not altered by exposure to CdCl2. Because cadmium was not incorporated into sperm chromatin at levels above 0.02 microg/g dry weight, the data cast doubt on hypotheses that suggest that reduced male fertility may result from incorporation of cadmium into sperm chromatin.

  13. Long-term subjective benefit with a bone conduction implant sound processor in 44 patients with single-sided deafness.

    Science.gov (United States)

    Desmet, Jolien; Wouters, Kristien; De Bodt, Marc; Van de Heyning, Paul

    2014-07-01

    Studies that investigate the subjective benefit from a bone conduction implant (BCI) sound processor in patients with single-sided sensorineural deafness (SSD) have been limited to examining short- and mid-term benefit. In the current study, we performed a survey among 44 SSD BCI users with a median follow-up time of 50 months. Forty-four experienced SSD BCI users participated in the survey, which consisted of the Abbreviated Profile of Hearing Aid Benefit, the Single-Sided Deafness Questionnaire, the Short Hearing Handicap Inventory for Adults, and a self-made user questionnaire. For patients with tinnitus, the Tinnitus Questionnaire was also completed. The results of the survey were correlated with contralateral hearing loss, age at implantation, duration of the hearing loss at the time of implantation, duration of BCI use, and the presence and burden of tinnitus. In total, 86% of the patients still used their sound processor. The Abbreviated Profile of Hearing Aid Benefit and the Short Hearing Handicap Inventory for Adults show a statistically significant overall improvement with the BCI. The Single-Sided Deafness Questionnaire and the user questionnaire showed that almost 40% of the patients reported daily use of the sound processor. However, the survey of daily use reveals benefit only in certain circumstances. Speech understanding in noisy situations is rated rather low, and 58% of all patients reported that their BCI benefit was less than expected. The majority of the patients reported an overall improvement from using their BCI. However, the number of users decreases during a longer follow-up time and patients get less enthusiastic about the device after an extended period of use, especially in noisy situations. However, diminished satisfaction because of time-related reductions in processor function could not be ruled out.

  14. Importance to include the term superficial musculoaponeurotic system in medical subject headings and in the international anatomical nomenclature.

    Science.gov (United States)

    Ferreira, Lydia Massako; Locali, Rafael Fagionato; Lapin, Guilherme Abbud Franco; Hochman, Bernardo

    2011-06-01

    To investigate the relevance of the term superficial musculoaponeurotic system (SMAS) and demonstrate that this term is important enough to be added to the MeSH database and listed in International Anatomical Nomenclature. Terms related to SMAS were selected from original articles retrieved from the ISI Web of Science and MEDLINE (PubMed) databases. Groups of terms were created to define a search strategy with high-sensitivity and restricted to scientific periodicals devoted to plastic surgery. This study included articles between January 1996 and May 2009, whose titles, abstracts, and keywords were searched for SMAS-related terms and all occurrences were recorded. A total of 126 original articles were retrieved from the main periodicals related to plastic surgery in the referred databases. Of these articles, 51.6% had SMAS-related terms in the abstract only, and 25.4% had SMAS-related terms in both the title and abstract. The term 'superficial musculoaponeurotic system' was present as a keyword in 19.8% of the articles. The most frequent terms were 'SMAS' (71.4%) and superficial musculoaponeurotic system (62.7%). The term SMAS refers to a structure relevant enough to start a discussion about indexing it as a keyword and as an official term in Terminologia Anatomica: International Anatomical Terminology.

  15. 10 CFR 70.14 - Foreign military aircraft.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Foreign military aircraft. 70.14 Section 70.14 Energy....14 Foreign military aircraft. The regulations in this part do not apply to persons who carry special nuclear material (other than plutonium) in aircraft of the armed forces of foreign nations subject to 49 U...

  16. 77 FR 22187 - Technical Amendment; Airworthiness Standards-Aircraft Engines

    Science.gov (United States)

    2012-04-13

    ... Federal Aviation Administration 14 CFR Part 33 Technical Amendment; Airworthiness Standards--Aircraft.... SUMMARY: This amendment corrects a number of errors in the airworthiness standards for aircraft engine... additional burden on any person. List of Subjects 14 CFR Part 33 Air transportation, Aircraft, Aviation...

  17. Short Term Effects of Neurodynamic Stretching and Static Stretching Techniques on Hamstring Muscle Flexibility in Healthy Male Subjects

    OpenAIRE

    Adel Rashad Ahmed; Ahmed Fathy Samhan

    2016-01-01

    Flexibility is a key component of rehabilitation and inadequate muscle extensibility remains a commonly accepted factor for musculoskeletal disorders. Studies on the most optimal technique for improving muscle flexibility are a widely debated. The aim of the study was to compare the effectiveness of neurodynamic and static stretching techniques on hamstring flexibility in healthy male subjects. This study was a randomized experimental trial; forty healthy male subjects with hamstr...

  18. A randomized lifestyle intervention with 5-year follow-up in subjects with impaired glucose tolerance: pronounced short-term impact but long-term adherence problems

    DEFF Research Database (Denmark)

    Lindahl, Bernt; Nilssön, Torbjörn K; Borch-Johnsen, Knut

    2009-01-01

    between 1995 and 2000, in 168 individuals with impaired glucose tolerance (IGT) and body mass index above 27 at start. The intensive intervention group (n = 83) was subjected to a 1-month residential lifestyle programme. The usual care group (n = 85) participated in a health examination ending...

  19. Transcending Library Catalogs: A Comparative Study of Controlled Terms in Library of Congress Subject Headings and User-Generated Tags in LibraryThing for Transgender Books

    Science.gov (United States)

    Adler, Melissa

    2009-01-01

    Perhaps the greatest power of folksonomies, especially when set against controlled vocabularies like the Library of Congress Subject Headings, lies in their capacity to empower user communities to name their own resources in their own terms. This article analyzes the potential and limitations of both folksonomies and controlled vocabularies for…

  20. Fluid-Structure Interaction in a Fluid-Filled Composite Structure Subjected to Low Velocity Impact

    Science.gov (United States)

    2016-06-01

    this study of impact force, deflection, and strain were measured in a carbon fiber reinforced polymer (CFRP) composite cylinder subjected to low...Sanchez, J. Lopez-Puente, and D. Varas, “On the influence of filling level in CFRP aircraft fuel tank subjected to high velocity impacts,” Composite ...and back sides. The baffle provided the greatest strain reduction at the high fill levels. 14. SUBJECT TERMS glass fiber composite , fluid structure

  1. Improved work ability and return to work following vocational multidisciplinary rehabilitation of subjects on long-term sick leave

    OpenAIRE

    Braathen, Tore; Veiersted, Kaj Bo; Heggenes, Jan

    2007-01-01

    Objective: To evaluate a vocational multidisciplinary rehabilitation programme for patients on long-term sick leave with respect to their work ability and return to work. Methods: A multidisciplinary rehabilitation programme was administered to an intervention group of 183 patients on long-term sick leave (mean 12.2 months). Effects of the treatment were compared with a control group (n = 96) recruited from the national sickness insurance record of patients on sick leave of 6??2 month...

  2. Model of aircraft noise adaptation

    Science.gov (United States)

    Dempsey, T. K.; Coates, G. D.; Cawthorn, J. M.

    1977-01-01

    Development of an aircraft noise adaptation model, which would account for much of the variability in the responses of subjects participating in human response to noise experiments, was studied. A description of the model development is presented. The principal concept of the model, was the determination of an aircraft adaptation level which represents an annoyance calibration for each individual. Results showed a direct correlation between noise level of the stimuli and annoyance reactions. Attitude-personality variables were found to account for varying annoyance judgements.

  3. Experimental Testing of Monopiles in Sand Subjected to One-Way Long-Term Cyclic Lateral Loading

    DEFF Research Database (Denmark)

    Roesen, Hanne Ravn; Ibsen, Lars Bo; Andersen, Lars Vabbersgaard

    2013-01-01

    In the offshore wind turbine industry the most widely used foundation type is the monopile. Due to the wave and wind forces the monopile is subjected to a strong cyclic loading with varying amplitude, maximum loading level, and varying loading period. In this paper the soil–pile interaction...

  4. Do subjects with whiplash-associated disorders respond differently in the short-term to manual therapy and exercise than those with mechanical neck pain?

    DEFF Research Database (Denmark)

    Castaldo, Matteo; Catena, Antonella; Chiarotto, Alessandro

    2017-01-01

    OBJECTIVE : To compare the short-term effects of manual therapy and exercise on pain, related disability, range of motion, and pressure pain thresholds between subjects with mechanical neck pain and whiplash-associated disorders. METHODS : Twenty-two subjects with mechanical neck pain and 28...... with whiplash-associated disorders participated. Clinical and physical outcomes including neck pain intensity, neck-related disability, and pain area, as well as cervical range of motion and pressure pain thresholds over the upper trapezius and tibialis anterior muscles, were obtained at baseline and after...... the intervention by a blinded assessor. Each subject received six sessions of manual therapy and specific neck exercises. Mixed-model repeated measures analyses of covariance (ANCOVAs) were used for the analyses. RESULTS : Subjects with whiplash-associated disorders exhibited higher neck-related disability (P = 0...

  5. Title Epidemic Model of a Concept within the Subject Classes of Patents: A Case Study on the Term RFID

    Directory of Open Access Journals (Sweden)

    Mohammad Tavakolizade Ravari

    2016-12-01

    Full Text Available The current research aims at studying the epidemic model of the term RFID within the classes of patents. Methodology: The research is descriptive and has been conducted based on the mathematical models of diseases. Research population consists of 35,627 granted patents from the USPTO database those which the terms RFID or Radio Frequency Identification occur in their titles or abstracts. Data analysis was performed through software like Excel, SPSS, and Ravar-Matrix. Findings show that the cumulative growth of sub-classes with the term RFID follows an S-logistic model. This is an evidence of natural growth rate for assigning the term RFID to the USPTO sub-classes over the years.  Other finding reveals that the term RFID has been entered into and exited from the sub-classes of patents like the SIS epidemic model of diseases. As a final conclusion, the most technical fields those that are susceptible for RFID technology, have been met this technology. On the base of SIS model, the epidemic of RFID technology has been reached a balance.

  6. THE SHORT-TERM EFFECT OF A HOME-BASED PROGRAM TO CORRECT FORWARD HEAD POSTURE IN ASYMPTOMATIC SUBJECTS

    Directory of Open Access Journals (Sweden)

    Ahmed Omar Abdelnaeem

    2015-08-01

    Full Text Available Background: Neck pain and dysfunction may be the consequence of adopting sustained non-neutral spinal postures. Such postures are associated with increased activation of the neck-shoulder stabilizer muscles, which eventually increase the loading of cervical spine. Forward head posture is a common postural dysfunction that has been associated with many musculoskeletal disorders. The purpose of the study was to investigate the effects of deep cervical flexor muscles training on the severity of forward head posture in asymptomatic subjects. Methods: Forty-one asymptomatic subjects volunteered in this study. Participants were randomly assigned into an intervention group (n= 20that received a home-based training of deep cervical flexor muscles for 6-weeks, and a control group(n= 21 that received only the assessment procedure. Subjects were assessed at baseline and 6weeks later with regards to the severity of forward head as indicated by the cranio-vertebral angle. Also, the strength and endurance of the deep flexor muscles were assessed. Results: After six weeks, participants in the intervention group showed significant improvement in all measured variables compared to the control group. Furthermore, participants in the intervention group showed significant difference in all measured variables after 6-weeks of training compared to baseline, whereas those in the control group remained the same. Conclusion: Six-weeks of deep cervical training improves forward head posture and deep flexors strength and endurance in asymptomatic subjects. Thus, this exercise could be used as a preventive measure against the development of neck dysfunction in at risk population even before the onset of any symptoms.

  7. Short Term Effects of Neurodynamic Stretching and Static Stretching Techniques on Hamstring Muscle Flexibility in Healthy Male Subjects

    Directory of Open Access Journals (Sweden)

    Adel Rashad Ahmed

    2016-05-01

    Full Text Available Flexibility is a key component of rehabilitation and inadequate muscle extensibility remains a commonly accepted factor for musculoskeletal disorders. Studies on the most optimal technique for improving muscle flexibility are a widely debated. The aim of the study was to compare the effectiveness of neurodynamic and static stretching techniques on hamstring flexibility in healthy male subjects. This study was a randomized experimental trial; forty healthy male subjects with hamstring tightness were randomly divided into two equal groups: The neurodynamic group and the static stretching group. Treatment was given for 5 consecutive days and the outcomes were measured using Active knee Extension Test and Straight Leg Raising. There was a significant improvement in hamstring flexibility following application of both neurodynamic and static stretching but the improvement in the neurodynamic group (p<0.001 was better than that of the static group (p<0.02. Results suggest that a neurodynamic stretching could increase hamstring flexibility to a greater extent than static stretching in healthy male subjects with a tight hamstring.

  8. Comparison of Subjective Sleep Quality of Long-Term Residents at Low and High Altitudes: SARAHA Study.

    Science.gov (United States)

    Gupta, Ravi; Ulfberg, Jan; Allen, Richard P; Goel, Deepak

    2018-01-15

    To study the effect of altitude on subjective sleep quality in populations living at high and low altitudes after excluding cases of restless legs syndrome (RLS). This population-based study was conducted at three different altitudes (400 m, 1,900-2,000 m, and 3,200 m above sea level). All consenting subjects available from random stratified sampling in the Himalayan and sub-Himalayan regions of India were included in the study (ages 18 to 84 years). Sleep quality and RLS status were assessed using validated translations of Pittsburgh Sleep Quality Index (PSQI) and Cambridge Hopkins RLS diagnostic questionnaire. Recent medical records were screened to gather data for medical morbidities. In the total sample of 1,689 participants included, 55.2% were women and average age of included subjects was 35.2 (± 10.9) years. In this sample, overall 18.4% reported poor quality of sleep (PSQI ≥ 5). Poor quality of sleep was reported more commonly at high altitude compared to low altitude (odds ratio [OR] = 2.65; 95% CI = 1.9-3.7; P quality of sleep were male sex, smoking, chronic obstructive pulmonary disease (COPD), and varicose veins. Binary logistic regression indicated that COPD (OR = 1.97; 95% CI = 1.36-2.86; P quality of sleep. This study showed that poor quality of sleep was approximately twice as prevalent at high altitudes compared to low altitudes even after removing the potential confounders such as RLS and COPD.

  9. Increased Serum PAI-1 Levels in Subjects with Metabolic Syndrome and Long-Term Adverse Mental Symptoms: A Population-Based Study

    Directory of Open Access Journals (Sweden)

    Anne Huotari

    2010-01-01

    Full Text Available Depression is an independent risk factor for cardiovascular diseases and is associated with metabolic syndrome (MetS. Levels of plasminogen activator inhibitor-1 (PAI-1, an inhibitor of tissue-type and urokinase-type plasminogen activators, are associated with MetS. To clarify the role of PAI-1 in subjects with long-term adverse mental symptomatology (LMS; including depression and MetS, we measured circulating PAI-1 levels in controls (n=111, in subjects with MetS and free of mental symptoms (n=42, and in subjects with both MetS and long-term mental symptoms (n=70. PAI-1 increased linearly across the three groups in men. In logistic regression analysis, men with PAI-1 levels above the median had a 3.4-fold increased likelihood of suffering from the comorbidity of long-term adverse mental symptoms and MetS, while no such associations were detected in women. In conclusion, our results suggest that in men high PAI-1 levels are independently associated with long-term mental symptomatology.

  10. Psychomotor and Memory Effects of Haloperidol, Olanzapine, and Paroxetine in Healthy Subjects After Short-Term Administration

    NARCIS (Netherlands)

    Morrens, M.; Wezenberg, E.; Verkes, R.J.; Hulstijn, W.; Ruigt, G.S.F.; Sabbe, B.G.C.

    2007-01-01

    Rationale: Impaired psychomotor function has been shown to be associated with clinical and functional outcome in schizophrenia. However, few studies have investigated the short-term effects of antipsychotics on the cognitive and psychomotor functions of this patient group. Because many confounding

  11. Psychomotor and memory effects of haloperidol, olanzapine, and paroxetine in healthy subjects after short-term administration.

    NARCIS (Netherlands)

    Morrens, M.; Wezenberg, E.; Verkes, R.J.; Hulstijn, W.; Ruigt, G.S.F.; Sabbe, B.G.C.

    2007-01-01

    RATIONALE: Impaired psychomotor function has been shown to be associated with clinical and functional outcome in schizophrenia. However, few studies have investigated the short-term effects of antipsychotics on the cognitive and psychomotor functions of this patient group. Because many confounding

  12. Short- and Long-Term Effectiveness of a Subject's Specific Novel Brain and Vestibular Rehabilitation Treatment Modality in Combat Veterans Suffering from PTSD.

    Science.gov (United States)

    Carrick, Frederick Robert; Pagnacco, Guido; McLellan, Kate; Solis, Ross; Shores, Jacob; Fredieu, Andre; Brock, Joel Brandon; Randall, Cagan; Wright, Cameron; Oggero, Elena

    2015-01-01

    Treatment for post-traumatic stress disorder (PTSD) in combat veterans that have a long-term positive clinical effect has the potential to modify the treatment of PTSD. This outcome may result in changed and saved lives of our service personnel and their families. In a previous before-after-intervention study, we demonstrated high statistical and substantively significant short-term changes in the Clinician Administered DSM-IV PTSD Scale (CAPS) scores after a 2-week trial of a subject's particular novel brain and vestibular rehabilitation (VR) program. The long-term maintenance of PTSD severity reduction was the subject of this study. We studied the short- and long-term effectiveness of a subject's particular novel brain and VR treatment of PTSD in subjects who had suffered combat-related traumatic brain injuries in terms of PTSD symptom reduction. The trial was registered as ClinicalTrials.gov Identifier: NCT02003352. We analyzed the difference in the CAPS scores pre- and post-treatment (1 week and 3 months) using our subjects as their matched controls. The generalized least squares (GLS) technique demonstrated that with our 26 subjects in the 3 timed groups the R (2) within groups was 0.000, R (2) between groups was 0.000, and overall the R (2) was 0.000. The GLS regression was strongly statistically significant z = 21.29, p < 0.001, 95% CI [58.7, 70.63]. The linear predictive margins over time demonstrated strong statistical and substantive significance of decreasing PTSD severity scores for all timed CAPS tests. Our investigation has the promise of the development of superior outcomes of treatments in this area that will benefit a global society. The length of the treatment intervention involved (2 weeks) is less that other currently available treatments and has profound implications for cost, duration of disability, and outcomes in the treatment of PTSD in combat veterans.

  13. Short and long term effectiveness of a subject's specific novel brain and vestibular rehabilitation treatment modality in combat veterans suffering from PTSD

    Directory of Open Access Journals (Sweden)

    Frederick Robert Carrick

    2015-06-01

    Full Text Available AbstractIntroduction: Treatment for post-traumatic stress disorder (PTSD in combat veterans that have a long-term positive clinical effect has the potential to modify the treatment of PTSD. This outcome may result in changed and saved lives of our service personnel and their families. In a previous before-after-intervention study we demonstrated high statistical and substantively significant short-term changes in the Clinician Administered DSM-IV PTSD Scale (CAPS scores after a two week trial of a subject's particular novel brain and vestibular rehabilitation (VR program. The long-term maintenance of PTSD severity reduction was the subject of this study.Material and Methods:We studied the short and long term effectiveness of a subject's particular novel brain and VR treatment of PTSD in subjects who had suffered combat-related traumatic brain injuries in terms of PTSD symptom reduction. The trial was registered as ClinicalTrials.gov Identifier: NCT02003352. We analyzed the difference in the CAPS scores pre and post treatment (one week and three months using our subjects as their matched controls. Results:The generalized least squares (GLS technique demonstrated that with our 26 subjects in the 3 timed groups the R2 within groups was 0.000, R2 between groups was 0.000 and overall the R2 was 0.000. The GLS regression was strongly statistically significant z = 21.29, p < 0.001, 95% CI [58.7, 70.63]. The linear predictive margins over time demonstrated strong statistical and substantive significance of decreasing PTSD severity scores for all timed CAPS tests.Discussion:Our investigation has the promise of the development of superior outcomes of treatments in this area that will benefit a global society. The length of the treatment intervention involved (two weeks is less that other currently available treatments and has profound implications for cost, duration of disability and outcomes in the treatment of PTSD in combat veterans.

  14. The effects of a nucleotide supplement on the immune and metabolic response to short term, high intensity exercise performance in trained male subjects.

    Science.gov (United States)

    Mc Naughton, L; Bentley, D; Koeppel, P

    2007-03-01

    The aim of this work was to determine the ergogenic effects of a nucleotide supplement on the metabolic and immune responses to short term high intensity exercise in volunteer, trained, male subjects. Thirty moderately trained male subjects were randomly divided into 3 equal sized groups, control (C), placebo (P) or experimental (E). Each subject undertook a 2 min maximal exercise test prior to, and after 60 days, on either a nucleotide (E) or placebo supplement. Prior to exercise testing unstimulated saliva samples and blood samples were taken. Saliva was analysed for cortisol and IgA, while blood was analysed for lactate, lactate dehydrogenase and creatine kinase. The postexercise C value was significantly higher than the pre-exercise concentration (Pchanges in blood lactate, lactate dehydrogenase, or creatine kinase concentrations post supplementation. We concluded that a chronically ingested nucleotide supplement blunts the response of the hormones associated with physiological stress.

  15. A short-term, comprehensive, yoga-based lifestyle intervention is efficacious in reducing anxiety, improving subjective well-being and personality

    Science.gov (United States)

    Yadav, Raj Kumar; Magan, Dipti; Mehta, Manju; Mehta, Nalin; Mahapatra, Sushil Chandra

    2012-01-01

    Objective: To assess the efficacy of a short-term comprehensive yoga-based lifestyle intervention in reducing anxiety, improving subjective well-being and personality. Materials and Methods: The study is a part of an ongoing larger study at a tertiary care hospital. Participants (n=90) included patients with chronic diseases attending a 10-day, yoga-based lifestyle intervention program for prevention and management of chronic diseases, and healthy controls (n=45) not attending any such intervention. Primary Outcome Measures: Change in state and trait anxiety questionnaire (STAI-Y; 40 items), subjective well-being inventory (SUBI; 40 items), and neuroticism extraversion openness to experience five factor personality inventory revised (NEO-FF PI-R; 60 items) at the end of intervention. Results: Following intervention, the STAI-Y scores reduced significantly (Panxiety and improve subjective well-being and personality in patients with chronic diseases. PMID:22869998

  16. Aircraft en route noise annoyance

    Science.gov (United States)

    Mccurdy, David A.

    1990-01-01

    Results are reported from a laboratory experiment conducted in order to quantify the annoyance experienced by people on the ground in response to en route noise (ERN) generated by aircraft at cruise conditions. Objectives included the comparison of annoyance responses to ERN with the annoyance responses to takeoff and landing noise; the comparison of the annoyance responses to advanced turboprop aircraft ERN with those of the turbofan ERN; and also the ability of aircraft noise measurement procedures and corrections to predict annoyance to ERN. Tests were conducted at the Langley Acoustics Research Laboratory on 32 human subjects selected at random. Subjects judged the annoyance level of 24 Propfan Test Assessment advanced turboprop ERN stimuli, 18 conventional turbofan ERN stimuli, and 60 conventional turboprop and turbofan takeoff and landing noise stimuli. Analysis of resulting data compared annoyance responses to different aircraft types and operations, examined the ability of current noise measurement and correction procedures to predict annoyance ERN, and calculated optimum duration correction magnitudes for ERN.

  17. The effect of duration of exercise at the ventilation threshold on subjective appetite and short-term food intake in 9 to 14 year old boys and girls

    Directory of Open Access Journals (Sweden)

    Pencharz Paul B

    2009-10-01

    Full Text Available Abstract Background The effect of exercise on subjective appetite and short-term food intake has received little investigation in children. Despite a lack of reported evaluation of short-duration activity programs, they are currently being implemented in schools as a means to benefit energy balance. The purpose of this study was to determine the effect of duration of exercise at the ventilation threshold (VeT on subjective appetite and short-term food intake in normal weight boys and girls aged 9 to 14 years. Methods On 4 separate mornings and in random order, boys (n = 14 and girls (n = 15 completed 2 rest or 2 exercise treatments for 15 (short-duration; SD or 45 min (long-duration; LD at their previously measured VeT, 2 h after a standardized breakfast. Subjective appetite was measured at regular intervals during the study sessions and food intake from a pizza meal was measured 30 min after rest or exercise. Results An increase in average appetite, desire to eat, and hunger (p Conclusion Neither SD nor LD exercise at the VeT increased short-term food intake and SD exercise attenuated increases in appetite. Thus, SD exercise programs in schools may be an effective strategy for maintaining healthier body weights in children.

  18. METHOD IMPROVEMENT FOR DETERMINING THE TECHNICAL LEVEL OF CIVIL AIRCRAFT

    Directory of Open Access Journals (Sweden)

    2016-01-01

    Full Text Available Aircraft are high-tech engineering products which are characterized by a wide range of properties including the two most important groups that respectively characterize the efficiency and technical level.Improving the aircraft efficiency is an essential factor for air transport development, but the efficiency can not be fully describe the technical system, especially in forecasting and new technology requirements development. Aircraft de- signer must evaluate the prospects of a technical solution, but it’s not always possible to calculate the efficiency accuratelyat the design stage. The operator should be able to choose the most technically-advanced aircraft available in the market inorder not to let it grow obsolete quickly. This determines the need for non-economic evaluation of technical systems that can be done by assessment of their technical level.The technical level is a general index that includes a set of technical perfection indicators. Technical perfection is reflected in terms of material and energy intensity, in terms of ergonomics, safety, etc. and is achieved as a result of origi- nal design solutions, the use of new high-strength low-density materials, the introduction of advanced technological pro-cesses, calculation methods, verification, testing, etc.There is a tight connection between the product properties and its weight, because weight is the material reflection of these properties. Therefore, improvement of the product properties usually leads to an intense increase of its weight. To deal with this phenomenon is only possible with widely using scientific and technical progress results. In accordance with this, the technical perfection can be interpreted as a major component of quality that is created without the weight increase. This approach requires investment in research and testing new technical solutions.The method was developed to determine the technical level of civil long-haul aircraft which has been modified to

  19. Propulsion controlled aircraft computer

    Science.gov (United States)

    Cogan, Bruce R. (Inventor)

    2010-01-01

    A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.

  20. GRAPHICAL MODELS OF THE AIRCRAFT MAINTENANCE PROCESS

    Directory of Open Access Journals (Sweden)

    Stanislav Vladimirovich Daletskiy

    2017-01-01

    Full Text Available The aircraft maintenance is realized by a rapid sequence of maintenance organizational and technical states, its re- search and analysis are carried out by statistical methods. The maintenance process concludes aircraft technical states con- nected with the objective patterns of technical qualities changes of the aircraft as a maintenance object and organizational states which determine the subjective organization and planning process of aircraft using. The objective maintenance pro- cess is realized in Maintenance and Repair System which does not include maintenance organization and planning and is a set of related elements: aircraft, Maintenance and Repair measures, executors and documentation that sets rules of their interaction for maintaining of the aircraft reliability and readiness for flight. The aircraft organizational and technical states are considered, their characteristics and heuristic estimates of connection in knots and arcs of graphs and of aircraft organi- zational states during regular maintenance and at technical state failure are given. It is shown that in real conditions of air- craft maintenance, planned aircraft technical state control and maintenance control through it, is only defined by Mainte- nance and Repair conditions at a given Maintenance and Repair type and form structures, and correspondingly by setting principles of Maintenance and Repair work types to the execution, due to maintenance, by aircraft and all its units mainte- nance and reconstruction strategies. The realization of planned Maintenance and Repair process determines the one of the constant maintenance component. The proposed graphical models allow to reveal quantitative correlations between graph knots to improve maintenance processes by statistical research methods, what reduces manning, timetable and expenses for providing safe civil aviation aircraft maintenance.

  1. The contribution of aircraft emissions to the atmospheric sulfur budget

    Energy Technology Data Exchange (ETDEWEB)

    Kjellstroem, E. [Stockholm Univ. (Sweden). Dept. of Meteorology; Feichter, J. [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); Sausen, R.; Hein, R. [Deutsches Zentrum fuer Luft- und Raumfahrt (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1998-01-01

    An atmospheric general circulation model including the atmospheric sulfur cycle has been used to investigate the impact of aircraft sulfur emissions on the global sulfur budget of the atmosphere. The relative contribution from aircraft sulfur to the atmospheric sulfate burden is larger than the ratio between aircraft emissions and surface emissions due to the calculated long turn-over time of aircraft sulfate (about 12 days). However, in terms of the sulfate mass balance, aircraft emissions are small, contributing about 1% of the total sulfate mass north of 40 deg C where the aircraft emissions are largest. Despite this small contribution to sulfate mass, the aircraft emissions could potentially significantly enhance the background number concentration of aerosol particles. Based on the model calculations the increased stratospheric background aerosol mass observed during the last decades can not be explained by increased aircraft sulfur emissions 50 refs, 9 figs, 4 tabs

  2. Characterization of an anaerobic baffled reactor treating dilute aircraft de-icing fluid and long term effects of operation on granular biomass.

    Science.gov (United States)

    Marin, Juan; Kennedy, Kevin J; Eskicioglu, Cigdem

    2010-04-01

    Successful treatment of dilute ethylene glycol based-aircraft de-icing fluid (ADF) was achieved using a four compartment, anaerobic baffled reactor (ABR). Three ADF concentrations (0.04, 0.07, and 0.13%v/v) were continuously fed at different hydrological retention times (HRTs; 24, 12, 6 and 3h) with concomitant organic loading rates (OLRs) varying between 0.3 and 6 kg chemical oxygen demand (COD)/m(3)/d. ABR achieved over 75% soluble COD removal and an average methane production potential of 0.30+/-0.05LCH(4)/gCOD(removed) at 33 degrees C for the experimental conditions evaluated. The different experimental conditions tested and a four-month summer shut-down simulation had no significant effect on reactor performance or on the settling characteristics of the granular biomass, which remained almost constant during the study. Biomass specific acetoclastic activity however, changed through the study; increasing two fold for the last three compartments and decreasing almost the same magnitude for the first compartment compared to inoculum, suggesting that a new distribution of microbial consortia was established in each compartment of the reactor by the end of the study. Copyright 2009 Elsevier Ltd. All rights reserved.

  3. Short-term objective and subjective evaluation of small-diameter implants used to support and retain mandibular prosthesis.

    Science.gov (United States)

    Brandt, Robert; Hollis, Scott; Ahuja, Swati; Adatrow, Pradeep; Balanoff, William

    2012-01-01

    The introduction of small-diameter implants has provided dentists the means of providing edentulous and partially edentulous patients with immediate functioning transitional prostheses while definitive restorations are being fabricated. The successful use of these small-diameter implants for temporary stabilization of prostheses has led many clinicians to explore the option of using them as a definitive alternative, especially as the technique requires minimal time and also is economical for the patients. To date, there has been no study with multiple patients looking at both the subjective and objective outcomes of these small-diameter implants. Twenty-seven edentulous patients were enrolled in this study, seven of them were smokers. One-hundred and eight small-diameter (2.0 mm, MDL) implants were surgically placed in 24 edentulous mandibles. All implants were immediately loaded. The patients filled out a screening questionnaire and four subsequent questionnaires to test their satisfaction with the altered prosthesis at 6, 12, 18 and 24 months. The survival of the implants was also noted. Smokers had an implant survival of 79%. Non-smokers had an implant survival of 100%. The results of the questionnaire indicated an overall satisfaction with the implant-supported prosthesis.

  4. Homebuilt aircraft crashes.

    Science.gov (United States)

    Hasselquist, A; Baker, S P

    1999-06-01

    While the number of general aviation crashes has decreased over the 5 yr prior to 1993, the total number of homebuilt aircraft crashes has increased by nearly 25%. Research was undertaken to analyze these crashes and identify causal factors or unique problems associated with homebuilt aircraft. Some 200 National Transportation Safety Board computer records and two-page descriptive briefs were analyzed for homebuilt aircraft crashes during 1993. Using descriptive epidemiology, variables were looked at in detail and comparisons were made with general aviation crashes during the-same year. Despite accounting for only 3% of all hours flown in general aviation certified aircraft for 1993, homebuilt aircraft accounted for 10% of the crashes and experienced a higher fatal crash rate. Crashes due to mechanical failure and crashes on takeoff and climb were more common in homebuilt aircraft as compared with general aviation. Other significant causal factors for homebuilt aircraft crashes included: minimal flight time in type specific aircraft, improper maintenance and improper design or assembly. Greater emphasis needs to be placed on educating homebuilt aircraft owners in the importance of following Federal Aviation Administration guidelines for certification and air worthiness testing. Understanding the aircraft's specifications and design limitations prior to the initial flight and properly maintaining the aircraft should also help to reverse the trend in the number of these crashes and subsequent lives lost. A system for assuring that all home-built aircraft are certified and more accurate reporting of flight hours are needed for accurate tracking of homebuilt aircraft crash rates.

  5. Effects of short-term very low-calorie diet on intramyocellular lipid and insulin sensitivity in nondiabetic and type 2 diabetic subjects.

    Science.gov (United States)

    Lara-Castro, Cristina; Newcomer, Bradley R; Rowell, Jennifer; Wallace, Penny; Shaughnessy, Sara M; Munoz, A Julian; Shiflett, Alanna M; Rigsby, Dana Y; Lawrence, Jeannine C; Bohning, Daryl E; Buchthal, Steven; Garvey, W Timothy

    2008-01-01

    The study aimed to analyze the effects of a short-term very low-calorie diet (VLCD) on intramyocellular lipid (IMCL), total body fat, and insulin sensitivity in a group of obese nondiabetic and type 2 diabetic subjects. Seven untreated type 2 diabetic and 5 obese nondiabetic individuals were studied before and after a 6-day VLCD using proton magnetic resonance spectroscopy to quantify IMCL, dual-energy x-ray absorptiometry to assess body fat, and hyperinsulinemic-euglycemic clamps to measure peripheral insulin sensitivity. In both groups, decrements in total body fat mass and body mass index were small but statistically significant. In contrast, the diet resulted in a pronounced reduction in IMCL compared with baseline values in nondiabetic subjects (56% decrease) and type 2 diabetic subjects (40% decrease) (P increase in maximally stimulated glucose disposal rate (P lipid was significantly correlated with insulin sensitivity (r = -0.69, P insulin sensitivity was related to measures of general adiposity such as body mass index, percentage of body fat, or total body fat (P = not significant). In conclusion, short-term VLCD is accompanied by small decrements in general adiposity, marked decrease in IMCL, and an increase in insulin sensitivity in nondiabetic and type 2 diabetic subjects. Therefore, rapid amelioration of insulin resistance by VLCD can be partially explained by loss of IMCL both in nondiabetic and type 2 diabetic subjects in the absence of substantial changes in total body fat. These observations are consistent with the idea that insulin resistance is more directly related to IMCL rather than to body fat per se.

  6. Long-term adherence to antimuscarinic drugs when treating overactive bladder in the older: Subjective reason and objective factors

    Directory of Open Access Journals (Sweden)

    Kirill Vladimirovich Kosilov

    2017-03-01

    Full Text Available Purpose: Comparison of subjective reasons for the refusal of antimuscarinic treatment and the state of objective economic, social, psychological and health status markers in the elderly with overactive bladder. Materials and Methods: One thousand seven hundred thirty-six (1,736 patients participated in the experiment: 1,036 or 59.7% of women, and 700 or 40.3% of men aged over 60 years (average age, 68.1 years who took antimuscarinic (AM drugs during the year. The control of objective parameters was carried out by studying patients’ medical records, the use of overactive bladder questionnaire short form and Medical Outcomes Study 36-item Shor-Form Health Survey, voiding diaries, uroflowmetry, as well as income certificates from the Tax Inspectorate, support documentation for expenses on drugs. Results: Fifty-two point six percent (52.6% of patients preserved adherence to treatment during the first 6 months, 30.1% – during the follow-up period. The average time of reaching a 30-day break in the AM drugs administration was 174 days. In 36.5% of cases of the refusal of treatment, patients referred to medical reasons for the refusal, in 31.6% of cases disturbance was established in objective health status markers (differences were significant in 30% of the follow-up time. The percentage of refusals of treatment for social and psychological reasons (13.2% was significantly lower (p≤0.05, than the percentage of individuals with statuses altered objectively (21.9%. Conclusions: A significant share of elderly patients taking AM drugs when treating overactive bladder is inclined to overestimate the importance of health factors influencing their decisions and to underestimate the importance of social and psychological factors, and an urologist should take it into account for the efficacy evaluation.

  7. Long-term adherence to antimuscarinic drugs when treating overactive bladder in the older: Subjective reason and objective factors.

    Science.gov (United States)

    Kosilov, Kirill Vladimirovich; Loparev, Sergay Alexandrovich; Kuzina, Irina Gennadyevna; Geltser, Boris Izrailevich; Shakirova, Olga Viktorovna; Zhuravskaya, Natalya Sergeevna; Lobodenko, Alexandra

    2017-03-01

    Comparison of subjective reasons for the refusal of antimuscarinic treatment and the state of objective economic, social, psychological and health status markers in the elderly with overactive bladder. One thousand seven hundred thirty-six (1,736) patients participated in the experiment: 1,036 or 59.7% of women, and 700 or 40.3% of men aged over 60 years (average age, 68.1 years) who took antimuscarinic (AM) drugs during the year. The control of objective parameters was carried out by studying patients' medical records, the use of overactive bladder questionnaire short form and Medical Outcomes Study 36-item Shor-Form Health Survey, voiding diaries, uroflowmetry, as well as income certificates from the Tax Inspectorate, support documentation for expenses on drugs. Fifty-two point six percent (52.6%) of patients preserved adherence to treatment during the first 6 months, 30.1% - during the follow-up period. The average time of reaching a 30-day break in the AM drugs administration was 174 days. In 36.5% of cases of the refusal of treatment, patients referred to medical reasons for the refusal, in 31.6% of cases disturbance was established in objective health status markers (differences were significant in 30% of the follow-up time). The percentage of refusals of treatment for social and psychological reasons (13.2%) was significantly lower (p≤0.05), than the percentage of individuals with statuses altered objectively (21.9%). A significant share of elderly patients taking AM drugs when treating overactive bladder is inclined to overestimate the importance of health factors influencing their decisions and to underestimate the importance of social and psychological factors, and an urologist should take it into account for the efficacy evaluation.

  8. Proficiency in Positive versus Negative Emotion Identification and Subjective Well-being among Long-term Married Elderly Couples

    Directory of Open Access Journals (Sweden)

    Raluca ePetrican

    2014-04-01

    Full Text Available Evidence is accruing that positive emotions play a crucial role in shaping a healthy interpersonal climate. Inspired by this research, the current investigation sought to shed light on the link between proficiency in identifying positive versus negative emotions and a close partner’s well-being. To this end, we conducted two studies with neurologically intact elderly married couples (Study 1 and an age-matched clinical sample, comprising married couples in which one spouse had been diagnosed with Parkinson’s Disease (Study 2, which tends to hinder emotional expressivity. To assess proficiency in identifying emotions from whole body postures, we had participants in both studies complete a pointlight walker task, featuring four actors (two male, two female expressing one positive (i.e., happiness and three negative (i.e., sadness, anger, fear basic emotions. Participants also filled out measures of subjective well-being. Among Study 1’s neurologically intact spouses, greater expertise in identifying positive (but not negative emotions was linked to greater partner life satisfaction (but not hedonic balance. Spouses of PD patients exhibited increased proficiency in identifying positive emotions relative to controls, possibly reflective of compensatory mechanisms. Complementarily, relative to controls, spouses of PD patients exhibited reduced proficiency in identifying negative emotions and a tendency to underestimate their intensity. Importantly, all of these effects attenuated with longer years from PD onset. Finally, there was evidence that it was increased partner expertise in identifying negative (rather than positive emotional states that predicted greater life satisfaction levels among the PD patients and their spouses. Our results thus suggest that positive versus negative emotions may play distinct roles in close relationship dynamics as a function of neurological status and disability trajectory.

  9. Proficiency in positive vs. negative emotion identification and subjective well-being among long-term married elderly couples.

    Science.gov (United States)

    Petrican, Raluca; Moscovitch, Morris; Grady, Cheryl

    2014-01-01

    Evidence is accruing that positive emotions play a crucial role in shaping a healthy interpersonal climate. Inspired by this research, the current investigation sought to shed light on the link between proficiency in identifying positive vs. negative emotions and a close partner's well-being. To this end, we conducted two studies with neurologically intact elderly married couples (Study 1) and an age-matched clinical sample, comprising married couples in which one spouse had been diagnosed with Parkinson's Disease (Study 2), which tends to hinder emotional expressivity. To assess proficiency in identifying emotions from whole body postures, we had participants in both studies complete a pointlight walker task, featuring four actors (two male, two female) expressing one positive (i.e., happiness) and three negative (i.e., sadness, anger, fear) basic emotions. Participants also filled out measures of subjective well-being. Among Study 1's neurologically intact spouses, greater expertise in identifying positive (but not negative) emotions was linked to greater partner life satisfaction (but not hedonic balance). Spouses of PD patients exhibited increased proficiency in identifying positive emotions relative to controls, possibly reflective of compensatory mechanisms. Complementarily, relative to controls, spouses of PD patients exhibited reduced proficiency in identifying negative emotions and a tendency to underestimate their intensity. Importantly, all of these effects attenuated with longer years from PD onset. Finally, there was evidence that it was increased partner expertise in identifying negative (rather than positive) emotional states that predicted greater life satisfaction levels among the PD patients and their spouses. Our results thus suggest that positive vs. negative emotions may play distinct roles in close relationship dynamics as a function of neurological status and disability trajectory.

  10. Beneficial Effects of Long-Term CPAP Treatment on Sleep Quality and Blood Pressure in Adherent Subjects With Obstructive Sleep Apnea.

    Science.gov (United States)

    Yang, Mei-Chen; Huang, Yi-Chih; Lan, Chou-Chin; Wu, Yao-Kuang; Huang, Kuo-Feng

    2015-12-01

    Obstructive sleep apnea (OSA) is associated with increased risk of cardiovascular diseases. Although CPAP is the first treatment choice for moderate-to-severe OSA, acceptance of and adherence to CPAP remain problematic. High CPAP adherence is generally defined as ≥4 h of use/night for ≥70% of the nights monitored. We investigated the long-term beneficial effects of CPAP on sleep quality and blood pressure in subjects with moderate-to-severe OSA according to high or low CPAP adherence. We retrospectively analyzed 121 subjects with moderate-to-severe OSA from August 2008 to July 2012. These subjects were divided into 3 groups: (1) no CPAP treatment (n = 29), (2) low CPAP adherence (n = 28), and (3) high CPAP adherence (n = 64). All subjects were followed up for at least 1 y. The 3 groups were compared regarding anthropometric and polysomnographic variables, presence of cardiovascular comorbidities, and blood pressure at baseline and at the last follow-up. The no-treatment group showed significant increases in oxygen desaturation index and blood pressure. The high-adherence group showed significant improvement in daytime sleepiness, apnea-hypopnea index (AHI), oxygen desaturation index, and blood pressure. Although the AHI was also significantly decreased after CPAP treatment in the low-adherence group, blood pressure remained unchanged. CPAP treatment had beneficial effects on both sleep quality and blood pressure only in subjects with OSA and high CPAP adherence who used CPAP for ≥4 h/night for ≥70% of nights monitored. Subjects with low CPAP adherence received beneficial effects on AHI, but not blood pressure. Copyright © 2015 by Daedalus Enterprises.

  11. Changes in total energy intake and macronutrient composition after bariatric surgery predict long-term weight outcome: findings from the Swedish Obese Subjects (SOS) study.

    Science.gov (United States)

    Kanerva, Noora; Larsson, Ingrid; Peltonen, Markku; Lindroos, Anna-Karin; Carlsson, Lena M

    2017-07-01

    Background: Approximately 20-30% of obese patients do not achieve successful weight outcomes after bariatric surgery.Objective: We examined whether short-term changes (≤0.5 y postsurgery) in energy intake and macronutrient composition after bariatric surgery could predict 10-y weight change.Design: Participants were recruited from the Swedish Obese Subjects (SOS) study, which was a matched (nonrandomized) prospective trial that compared bariatric surgery with usual care for obese patients. A total of 2010 patients who underwent bariatric surgery were included in the study. Physical examinations (e.g., weight) and questionnaires (e.g., dietary questionnaire) were completed before and 0.5, 1, 2, 3, 4, 6, 8, and 10 y after surgery. For the main analytic strategy, a linear mixed model was implemented, which included repeated measures with a random intercept and an unstructured covariance matrix.Results: Short-term changes in energy intake (P bariatric surgery. At the 10-y follow-up, men and women with the largest reductions in energy intake had lost 7.3% and 3.9% more weight, respectively, compared with that of subjects with the smallest intake reductions (P bariatric surgery predicts long-term weight loss. Weight loss is also associated with a changing dietary macronutrient composition. This trial was registered at clinicaltrials.gov as NCT01479452. © 2017 American Society for Nutrition.

  12. Comparison of Dietary Macro and Micro Nutrient Intake between Iranian Patients with Long-term Complications of Sulphur Mustard Poisoning and Healthy Subjects.

    Science.gov (United States)

    -Mood, Mahdi Balali; Zilaee, Marzie; -Mobarhan, Majid Ghayour; Sheikh-Andalibi, Mohammad Sobhan; Mohades-Ardabili, Hossein; Dehghani, Hamideh; Ferns, Gordon

    2014-01-01

    Patients with long-term complications of sulfur mustard (SM) poisoning are often less able to undertake optimum levels of physical activity and adequately control their dietary intake. The aim of present study was to investigate the dietary intake of patients with SM poisoning in comparison to a control group Methods: The study was undertaken on 55 Iranian male veterans, who had > 25% disabilities due to long-term complications of SM poisoning and 55 men age-matched healthy subjects. A previously validated food frequency questionnaire (FFQ) was used for measuring dietary macro/micro nutrient intake for both groups; and the results were analysed using Dietplan6 software. Analysis of macro/micro nutrients in dietary intakes of the patients versus the controls showed a significantly lower intake of several nutrients including selenium and carbohydrate. On the other hand, the dietary intake of trans-fatty acids and iodine were significantly higher in these patients. Long-term complications of SM poisoning in the Iranian veterans induce both chemical and physical disabilities. Macro/micro nutrient intake in these patients was significantly different in comparison with matched, healthy subjects. Dietary advice for these patients should be strongly recommended to these patients in order to prevent other chronic diseases.

  13. Reproducibility and seasonal variation of ambulatory short-term heart rate variability in healthy subjects during a self-selected rest period and during sleep.

    Science.gov (United States)

    Kristiansen, Jesper; Olsen, Annemarie; Skotte, Jørgen H; Garde, Anne Helene

    2009-01-01

    Although ambulatory measurements of heart rate variability (HRV) are widely used, the reproducibility and seasonal variation of ambulatory sampled short-term HRV measurements in healthy participants has not been investigated before. In the present study we collected ambulatory ECGs from 19 healthy participants monthly for 12 months, and for a sub-group of 12 participants weekly for one month. Frequency-domain HRV-metrics were calculated for 5 min ECG segments during (i) a 15-min self-selected rest period (awake period), and (ii) a 30-min sleep period starting 45 min after estimated sleep onset. Total, within- and between-subject coefficient of variation (CV) and seasonal variation were estimated for ln (TP), ln (LFP), ln (HFP), ln (LF/HF), LFnu, HFnu, the mean heart period and the ECG derived respiratory frequency.The within- and between-subject CV varied considerably between different variables, from 100% for ln (LF/HF). Within- and between-subject CV of ln (HFP), LFnu and HFnu were 10-40%. A weak, but significant, seasonal variation was found for ln (TP) (p = 0.05), ln (LFP) (p<0.05) and the respiratory frequency (p<0.01), but the seasonal variation did not affect the within-subject CV. Furthermore, sample size calculations demonstrated that the reproducibility was sufficient for ambulatory HRV measurements to be used to study autonomic cardiac regulation in healthy populations.

  14. Achievement emotions in elementary, middle, and high school: how do students feel about specific contexts in terms of settings and subject-domains?

    Science.gov (United States)

    Raccanello, Daniela; Brondino, Margherita; De Bernardi, Bianca

    2013-12-01

    The present work investigates students' representation of achievement emotions, focusing in context-specific situations in terms of settings and subject-domains, as a function of grade level. We involved 527 fourth-, seventh-, and eleventh-graders, who evaluated ten discrete emotions through questionnaires, with reference to verbal language and mathematics, and different settings (class, homework, tests). Confirmatory multitrait-multimethod analyses indicated higher salience of subject-domains rather than settings for all the emotions; however, complexity of reality was best explained when also settings were accounted for. Analyses of variance revealed higher intensity of positive emotions for younger students, and the opposite pattern for older students; significant differences for most of the emotions based on the evaluative nature of settings, moderated by class levels; more intense positive emotions for mathematics and more intense negative emotions for Italian. Results are discussed considering their theoretical and applied relevance, corroborating previous literature on domain-specificity. © 2013 The Scandinavian Psychological Associations.

  15. [Contribution of the study of singing in tune in musically non-expert subjects: importance of short term memory of the pitch (19 to 28 year-old subjects)].

    Science.gov (United States)

    Belin, S; Peuvergne, A; Sarfati, J

    2005-01-01

    In the singing, which requires precise knowledge of the relevant musical code in use, accuracy of intonation plays a central role. Singing in tune requires to perceive pitch precisely and to memorize it before planning and executing the accurate vocal motion, which allows the exact emission of the correct pitch. Our work investigated the role of short term memory of pitch on singing accuracy. For that purpose, the experimental protocol of Deutsch (1970) was adapted for a perception and a production task. Participants were selected for their singing accuracy and separated into two groups of ten singing in tune and ten out-of-tune. All participants perceived pitch height exactly and were musically non-experts. For the perception and the production tasks, participants had to either compare or reproduce single pitches or two-pitch-sets. For the perception task, participants had to compare either single pitches or two-pitch patterns, all separated by a five seconds delay. For the production task, participants had to reproduce either single pitches or two-pitch patterns after a five seconds delay. The five seconds delay was either filled with intervening numbers, or with intervening tones, or without any disturbing sound. In perception and production task, the presence of intervening tones disturbs deeply the success of the subjects for every trial. Performance of the in-tune singing group is better for all the exercises while the other group had difficulties on single pitches and two-pitch patterns and was more disturbed by the effect of the intervening material. The outcome suggests that short term memory of pitch and accuracy of intonation would be closely linked. Further research needs to specify if that would mean that troubles in singing in tune are a consequence of a low-efficient short term memory of pitch, or if that troubles would hold up the right construction of the short term memory of pitch.

  16. Aircraft agility maneuvers

    Science.gov (United States)

    Cliff, Eugene M.; Thompson, Brian G.

    1992-01-01

    A new dynamic model for aircraft motions is presented. This model can be viewed as intermediate between a point-mass model, in which the body attitude angles are control-like, and a rigid-body model, in which the body-attitude angles evolve according to Newton's Laws. Specifically, consideration is given to the case of symmetric flight, and a model is constructed in which the body roll-rate and the body pitch-rate are the controls. In terms of this body-rate model a minimum-time heading change maneuver is formulated. When the bounds on the body-rates are large the results are similar to the point-mass model in that the model can very quickly change the applied forces and produce an acceleration to turn the vehicle. With finite bounds on these rates, the forces change in a smooth way. This leads to a measurable effect of agility.

  17. Crashworthiness of composite seats for civil aircraft

    OpenAIRE

    Stephens, V. M.

    1992-01-01

    A study has been conducted into the design of civil aircraft seats which are forward-facing and use the lap-belt method of restraint. Within these terms of reference, the response of the seat restraint occupant system (SROS) to impact loading has been analysed using physical (dynamic testing) and analytical (computer simulation) modelling techniques. With the increasing use of fibre-reinforced polymer composites in aircraft for weight efficiency, and the consequent appearance of composite se...

  18. Objective and subjective sleep quality: Melatonin versus placebo add-on treatment in patients with schizophrenia or bipolar disorder withdrawing from long-term benzodiazepine use.

    Science.gov (United States)

    Baandrup, Lone; Glenthøj, Birte Yding; Jennum, Poul Jørgen

    2016-06-30

    Benzodiazepines are frequently long-term prescribed for the treatment of patients with severe mental illness. This prescribing practice is problematic because of well-described side effects including risk of dependence. We examined the efficacy of prolonged-release melatonin on objective and subjective sleep quality during benzodiazepine discontinuation and whether sleep variables were associated with benzodiazepine withdrawal. Eligible patients included adults with a diagnosis of schizophrenia, schizoaffective disorder, or bipolar disorder and long-term use of benzodiazepines in combination with antipsychotics. All participants gradually tapered the use of benzodiazepines after randomization to add-on treatment with melatonin versus placebo. Here we report a subsample of 23 patients undergoing sleep recordings (one-night polysomnography) and 55 patients participating in subjective sleep quality ratings. Melatonin had no effect on objective sleep efficiency, but significantly improved self-reported sleep quality. Reduced benzodiazepine dosage at the 24-week follow-up was associated with a significantly decreased proportion of stage 2 sleep. These results indicate that prolonged-release melatonin has some efficacy for self-reported sleep quality after gradual benzodiazepine dose reduction, and that benzodiazepine discontinuation is not associated with rebound insomnia in medicated patients with severe mental illness. However, these findings were limited by a small sample size and a low retention rate. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Treatment outcome and long-term stability of skeletal changes following maxillary distraction in adult subjects of cleft lip and palate

    Directory of Open Access Journals (Sweden)

    Satinder Pal Singh

    2012-01-01

    Full Text Available Aim : To evaluate the treatment outcome and long-term stability of skeletal changes following maxillary advancement with distraction osteogenesis in adult subjects of cleft lip and palate. Materials and Methods: Total 12 North Indian adult patients in the age range of 17-34 years with cleft lip and palate underwent advancement of maxilla by distraction osteogenesis. Lateral cephalograms recorded prior to distraction, at the end of distraction, 6 months after distraction, and at least 24 months (mean 25.5 ± 1.94 months after distraction osteogenesis were used for the evaluation of treatment outcome and long-term stability of the skeletal changes. Descriptive analysis, ANOVA, and post-hoc test were used, and P-value 0.05 was considered as a statistically significant level. Results: Maxillary distraction resulted in significant advancement of maxilla (P<0.001. Counterclockwise rotation of the palatal plane took place after maxillary distraction. The position of the mandible and facial heights were stable during distraction. During the first 6 months of the post-distraction period, the maxilla showed relapse of approximately 30%. However, after 6 months post distraction, the relapse was very negligible. Conclusions: Successful advancement of maxilla was achieved by distraction osteogenesis in adult subjects with cleft lip and palate. Most of the relapse occurred during the first 6 months of post-distraction period, and after that the outcomes were stable.

  20. Treatment outcome and long-term stability of skeletal changes following maxillary distraction in adult subjects of cleft lip and palate.

    Science.gov (United States)

    Singh, Satinder Pal; Jena, Ashok Kumar; Rattan, Vidya; Utreja, Ashok Kumar

    2012-04-01

    To evaluate the treatment outcome and long-term stability of skeletal changes following maxillary advancement with distraction osteogenesis in adult subjects of cleft lip and palate. Total 12 North Indian adult patients in the age range of 17-34 years with cleft lip and palate underwent advancement of maxilla by distraction osteogenesis. Lateral cephalograms recorded prior to distraction, at the end of distraction, 6 months after distraction, and at least 24 months (mean 25.5 ± 1.94 months) after distraction osteogenesis were used for the evaluation of treatment outcome and long-term stability of the skeletal changes. Descriptive analysis, ANOVA, and post-hoc test were used, and P-value 0.05 was considered as a statistically significant level. Maxillary distraction resulted in significant advancement of maxilla (Ppalatal plane took place after maxillary distraction. The position of the mandible and facial heights were stable during distraction. During the first 6 months of the post-distraction period, the maxilla showed relapse of approximately 30%. However, after 6 months post distraction, the relapse was very negligible. Successful advancement of maxilla was achieved by distraction osteogenesis in adult subjects with cleft lip and palate. Most of the relapse occurred during the first 6 months of post-distraction period, and after that the outcomes were stable.

  1. Long-Term Monitoring of Physical Behavior Reveals Different Cardiac Responses to Physical Activity among Subjects with and without Chronic Neck Pain

    Directory of Open Access Journals (Sweden)

    David M. Hallman

    2015-01-01

    Full Text Available Background. We determined the extent to which heart rate variability (HRV responses to daily physical activity differ between subjects with and without chronic neck pain. Method. Twenty-nine subjects (13 women with chronic neck pain and 27 age- and gender-matched healthy controls participated. Physical activity (accelerometry, HRV (heart rate monitor, and spatial location (Global Positioning System (GPS were recorded for 74 hours. GPS data were combined with a diary to identify periods of work and of leisure at home and elsewhere. Time- and frequency-domain HRV indices were calculated and stratified by period and activity type (lying/sitting, standing, or walking. ANCOVAs with multiple adjustments were used to disclose possible group differences in HRV. Results. The pain group showed a reduced HRV response to physical activity compared with controls (p=.001, according to the sympathetic-baroreceptor HRV index (LF/HF, ratio between low- and high-frequency power, even after adjustment for leisure time physical activity, work stress, sleep quality, mental health, and aerobic capacity (p=.02. The parasympathetic response to physical activity did not differ between groups. Conclusions. Relying on long-term monitoring of physical behavior and heart rate variability, we found an aberrant sympathetic-baroreceptor response to daily physical activity among subjects with chronic neck pain.

  2. Long-term Safety and Efficacy of Latanoprostene Bunod 0.024% in Japanese Subjects with Open-Angle Glaucoma or Ocular Hypertension: The JUPITER Study.

    Science.gov (United States)

    Kawase, Kazuhide; Vittitow, Jason L; Weinreb, Robert N; Araie, Makoto

    2016-09-01

    Latanoprostene bunod (LBN) is a novel nitric oxide (NO)-donating prostaglandin F2α analog. We evaluated the long-term safety and intraocular pressure (IOP)-lowering efficacy of LBN ophthalmic solution 0.024% over 1 year in Japanese subjects with open-angle glaucoma (OAG) or ocular hypertension (OHT). This was a single-arm, multicenter, open-label, clinical study. Subjects aged 20 years and older with a diagnosis of OAG or OHT instilled 1 drop of LBN ophthalmic solution 0.024% in the affected eye(s) once daily in the evening for 52 weeks and were evaluated every 4 weeks. Safety assessments included vital signs, comprehensive ophthalmic exams, and treatment-emergent adverse events (AEs). Absolute and percent reductions from baseline in IOP were also determined. Of 130 subjects enrolled, 121 (93.1%) completed the study. Mean age was 62.5 years, and mean (standard deviation) baseline IOP was 19.6 (2.9) and 18.7 (2.6) mmHg in study eyes and treated fellow eyes, respectively. Overall, 76/130 (58.5%) and 78/126 (61.9%) subjects experienced ≥1 AEs in study eyes and treated fellow eyes, respectively. In both study eyes and treated fellow eyes, the most common AEs were conjunctival hyperemia, growth of eyelashes, eye irritation, and eye pain. At 52 weeks, 9% of treated eyes had an increase in iris pigmentation compared with baseline based on iris photographs. No safety concerns emerged based on vital signs or other ocular assessments. Mean reductions from baseline in IOP of 22.0% and 19.5% were achieved by week 4 in study and treated fellow eyes, respectively. These reductions were maintained through week 52 (P < 0.001 vs. baseline at all visits). Once daily LBN ophthalmic solution 0.024% was safe and well-tolerated in Japanese subjects with OAG or OHT when used for up to 1 year. Long-term treatment with LBN ophthalmic solution 0.024% provided significant and sustained IOP reduction. ClinicalTrials.gov identifier, NCT01895972. Bausch & Lomb, Inc. a division of

  3. Power Spectral Analysis of Short-Term Heart Rate Variability in Healthy and Arrhythmia Subjects by the Adaptive Continuous Morlet Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Ram Sewak SINGH

    2017-12-01

    Full Text Available Power spectral analysis of short-term heart rate variability (HRV can provide instant valuable information to understand the functioning of autonomic control over the cardiovascular system. In this study, an adaptive continuous Morlet wavelet transform (ACMWT method has been used to describe the time-frequency characteristics of the HRV using band power spectra and the median value of interquartile range. Adaptation of the method was based on the measurement of maximum energy concentration. The ACMWT has been validated on synthetic signals (i.e. stationary, non-stationary as slow varying and fast changing frequency with time modeled as closest to dynamic changes in HRV signals. This method has been also tested in the presence of additive white Gaussian noise (AWGN to show its robustness towards the noise. From the results of testing on synthetic signals, the ACMWT was found to be an enhanced energy concentration estimator for assessment of power spectral of short-term HRV time series compared to adaptive Stockwell transform (AST, adaptive modified Stockwell transform (AMST, standard continuous Morlet wavelet transform (CMWT and Stockwell transform (ST estimators at statistical significance level of 5%. Further, the ACMWT was applied to real HRV data from Fantasia and MIT-BIH databases, grouped as healthy young group (HYG, healthy elderly group (HEG, arrhythmia controlled medication group (ARCMG, and supraventricular tachycardia group (SVTG subjects. The global results demonstrate that spectral indices of low frequency power (LFp and high frequency power (HFp of HRV were decreased in HEG compared to HYG subjects (p<0.0001. While LFp and HFp indices were increased in ARCMG compared to HEG (p<0.00001. The LFp and HFp components of HRV obtained from SVTG were reduced compared to other group subjects (p<0.00001.

  4. Gastric bypass surgery is followed by lowered blood pressure and increased diuresis - long term results from the Swedish Obese Subjects (SOS study.

    Directory of Open Access Journals (Sweden)

    Peter Hallersund

    Full Text Available OBJECTIVE: To compare two bariatric surgical principles with regard to effects on blood pressure and salt intake. BACKGROUND: In most patients bariatric surgery induces a sustained weight loss and a reduced cardiovascular risk profile but the long-term effect on blood pressure is uncertain. METHODS: Cohort study with data from the prospective, controlled Swedish Obese Subjects (SOS study involving 480 primary health care centres and 25 surgical departments in Sweden. Obese patients treated with non-surgical methods (Controls, n = 1636 and n = 1132 at 2 y and 10 y follow up, respectively were compared to patients treated with gastric bypass (GBP, n = 245 and n = 277, respectively or purely restrictive procedures (vertical banded gastroplasty or gastric banding; VBG/B, n = 1534 and n = 1064, respectively. RESULTS: At long-term follow-up (median 10 y GBP was associated with lowered systolic (mean: -5.1 mm Hg and diastolic pressure (-5.6 mmHg differing significantly from both VBG/B (-1.5 and -2.1 mmHg, respectively; p<0.001 and Controls (+1.2 and -3.8 mmHg, respectively; p<0.01. Diurnal urinary output was +100 ml (P<0.05 and +170 ml (P<0.001 higher in GBP subjects than in weight-loss matched VBG/B subjects at the 2 y and 10 y follow-ups, respectively. Urinary output was linearly associated with blood pressure only after GBP and these patients consumed approximately 1 g salt per day more at the follow-ups than did VBG/B (P<0.01. CONCLUSIONS: The purely restrictive techniques VBG/B exerted a transient blood pressure lowering effect, whereas gastric bypass was associated with a sustained blood pressure reduction and an increased diuresis. The daily salt consumption was higher after gastric bypass than after restrictive bariatric surgery.

  5. Fatigue tests on big structure assemblies of concorde aircraft

    Science.gov (United States)

    Nguyen, V. P.; Perrais, J. P.

    1972-01-01

    Fatigue tests on structural assemblies of the Concorde supersonic transport aircraft are reported. Two main sections of the aircraft were subjected to pressure, mechanical load, and thermal static tests. The types of fatigue tests conducted and the results obtained are discussed. It was concluded that on a supersonic aircraft whose structural weight is a significant part of the weight analysis, many fatigue and static strength development tests should be made and fatigue and thermal tests of the structures are absolutely necessary.

  6. Dedicated Solutions for Structural Health Monitoring of Aircraft Components

    OpenAIRE

    Pitropakis, Ioannis

    2015-01-01

    Aircraft structures, like any other mechanical structure, are subjected to various external factors that influence their lifetime. Mechanicalnbsp;and the environment are only some of the factors that can degrade the structure of aircraft components. Monitoring of these degradations by regular inspections or automated data recording is vital for the structural health of the critical components of an aircraft. This research proposes a number of dedicated solutions for structural health monitori...

  7. Annoyance caused by aircraft en route noise

    Science.gov (United States)

    Mccurdy, David A.

    1992-01-01

    A laboratory experiment was conducted to quantify the annoyance response of people on the ground to enroute noise generated by aircraft at cruise conditions. The en route noises were ground level recordings of eight advanced turboprop aircraft flyovers and six conventional turbofan flyovers. The eight advanced turboprop enroute noises represented the NASA Propfan Test Assessment aircraft operating at different combinations of altitude, aircraft Mach number, and propeller tip speed. The conventional turbofan en route noises represented six different commercial airliners. The overall durations of the en route noises varied from approximately 40 to 160 sec. In the experiment, 32 subjects judged the annoyance of the en route noises as well as recordings of the takeoff and landing noises of each of 5 conventional turboprop and 5 conventional turbofan aircraft. Each of the noises was presented at three sound pressure levels to the subjects in an anechoic listening room. Analysis of the judgments found small differences in annoyance between three combinations of aircraft type and operation. Current tone and corrections did not significantly improve en route annoyance prediction. The optimum duration-correction magnitude for en route noise was approximately 1 dB per doubling of effective duration.

  8. Subjective and objective peer approval evaluations and self-esteem development: A test of reciprocal, prospective, and long-term effects.

    Science.gov (United States)

    Gruenenfelder-Steiger, Andrea E; Harris, Michelle A; Fend, Helmut A

    2016-10-01

    A large body of literature suggests a clear, concurrent association between peer approval and self-esteem in adolescence. However, little empirical work exists on either the prospective or reciprocal relation between peer approval and self-esteem during this age period. Moreover, it is unclear from past research whether both subjectively perceived peer approval and objectively measured peer approval are related to subsequent self-esteem over time (and vice versa) and whether these paths have long-term associations into adulthood. Using data from a large longitudinal study that covers a time span of 2 decades, we examined reciprocal, prospective relations between self-esteem and peer approval during ages 12-16 in addition to long-term relations between these variables and later social constructs at age 35. Cross-lagged regression analyses revealed small but persistent effect sizes from both types of peer approval to subsequent self-esteem in adolescence, controlling for prior self-esteem. However, effects in the reverse direction were not confirmed. These findings support the notion that peer relationships serve an important function for later self-esteem, consistent with many theoretical tenets of the importance of peers for building a strong identity. Finally, we found long-term relations between adult social constructs and adolescent objective and subjective peer approval as well as self-esteem. Therefore, not only do peer relationships play a role in self-esteem development across adolescence, but they remain impactful throughout adulthood. In sum, the current findings highlight the lasting, yet small link between peer relationships and self-esteem development and call for investigations of further influential factors for self-esteem over time. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  9. 26 CFR 31.3306(m)-1 - American vessel and aircraft.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 15 2010-04-01 2010-04-01 false American vessel and aircraft. 31.3306(m)-1... vessel and aircraft. (a) The term “American vessel” means any vessel which is documented (that is....) (b) The term “American aircraft” means any aircraft registered under the laws of the United States...

  10. Evaluation of Long-Term Cochlear Implant Use in Subjects With Acquired Unilateral Profound Hearing Loss: Focus on Binaural Auditory Outcomes.

    Science.gov (United States)

    Mertens, Griet; De Bodt, Marc; Van de Heyning, Paul

    Cochlear implantation (CI) in subjects with unilateral profound sensorineural hearing loss was investigated. The authors of the present study demonstrated the binaural auditory outcomes in a 12- and 36-month prospective cohort outcome study. The present study aimed to do a long-term (LT) evaluation of the auditory outcomes in an analogous study group. LT evaluation was derived from 12 single-sided deaf (SSD) CI recipients and from 11 CI recipients with asymmetric hearing loss (AHL). A structured interview was conducted with each subjects. Speech perception in noise and sound localization were assessed in a CIOFF and in a CION condition. Four binaural effects were calculated: summation effect (S0N0), squelch effect (S0NCI), combined head shadow effect (SCIN0), and spatial release from masking (SRM). At the LT evaluation, the contribution of a CI or a bone conduction device on speech perception in noise was investigated in two challenging spatial configurations in the SSD group. All (23/23) subjects wore their CI 7 days a week at LT follow-up evaluation, which ranged from 3 to 10 years after implantation. In the SSD group, a significant combined head shadow effect of 3.17 dB and an SRM benefit of 4.33 dB were found. In the AHL group, on the other hand, the summation effect (2.00 dB), the squelch effect (2.67 dB), the combined head shadow effect (3.67 dB), and SRM benefit (2.00 dB) were significant at LT testing. In both the spatial challenging configurations, the speech in noise results was significantly worse in the condition with the bone conduction device compared with the unaided condition. No negative effect was found for the CION condition. A significant benefit in the CION condition was found for sound localization compared with the CIOFF condition in the SSD group and in the AHL group. All subjects wore their CI 7 days a week at LT follow-up evaluation. The presence of binaural effects has been demonstrated with speech in noise testing, sound localization

  11. Smart aircraft fastener evaluation (SAFE) system: a condition-based corrosion detection system for aging aircraft

    Science.gov (United States)

    Schoess, Jeffrey N.; Seifert, Greg; Paul, Clare A.

    1996-05-01

    The smart aircraft fastener evaluation (SAFE) system is an advanced structural health monitoring effort to detect and characterize corrosion in hidden and inaccessible locations of aircraft structures. Hidden corrosion is the number one logistics problem for the U.S. Air Force, with an estimated maintenance cost of $700M per year in 1990 dollars. The SAFE system incorporates a solid-state electrochemical microsensor and smart sensor electronics in the body of a Hi-Lok aircraft fastener to process and autonomously report corrosion status to aircraft maintenance personnel. The long-term payoff for using SAFE technology will be in predictive maintenance for aging aircraft and rotorcraft systems, fugitive emissions applications such as control valves, chemical pipeline vessels, and industrial boilers. Predictive maintenance capability, service, and repair will replace the current practice of scheduled maintenance to substantially reduce operational costs. A summary of the SAFE concept, laboratory test results, and future field test plans is presented.

  12. 14 CFR 21.128 - Tests: aircraft engines.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Tests: aircraft engines. 21.128 Section 21... engines. (a) Each person manufacturing aircraft engines under a type certificate only shall subject each engine (except rocket engines for which the manufacturer must establish a sampling technique) to an...

  13. Sizing Analysis for Aircraft Utilizing Hybrid-Electric Propulsion Systems

    Science.gov (United States)

    2011-03-18

    Lithium-Ion Batteries for Hybrid Electric Vehicles," Mitsubishi Motor Corporation, Japan, Technical Review 15, 2003. [40] Hiroaki et al Yoshida...SIZING ANALYSIS FOR AIRCRAFT UTILIZING HYBRID- ELECTRIC PROPULSION SYSTEMS THESIS Matthew D...of the U.S. Government and is not subject to copyright protection in the United States. AFIT/GAE/ENY/11-M26 SIZING ANALYSIS FOR AIRCRAFT

  14. Short-term effect of spinal manipulation on pain perception, spinal mobility, and full height recovery in male subjects with degenerative disk disease: a randomized controlled trial.

    Science.gov (United States)

    Vieira-Pellenz, Felipe; Oliva-Pascual-Vaca, Angel; Rodriguez-Blanco, Cleofás; Heredia-Rizo, Alberto Marcos; Ricard, François; Almazán-Campos, Ginés

    2014-09-01

    To evaluate the short-term effect on spinal mobility, pain perception, neural mechanosensitivity, and full height recovery after high-velocity, low-amplitude (HVLA) spinal manipulation (SM) in the lumbosacral joint (L5-S1). Randomized, double-blind, controlled clinical trial with evaluations at baseline and after intervention. University-based physical therapy research clinic. Men (N=40; mean age ± SD, 38 ± 9.14 y) with diagnosed degenerative lumbar disease at L5-S1 were randomly divided into 2 groups: a treatment group (TG) (n=20; mean age ± SD, 39 ± 9.12 y) and a control group (CG) (n=20; mean age ± SD, 37 ± 9.31 y). All participants completed the intervention and follow-up evaluations. A single L5-S1 SM technique (pull-move) was performed in the TG, whereas the CG received a single placebo intervention. Measures included assessing the subject's height using a stadiometer. The secondary outcome measures included perceived low back pain, evaluated using a visual analog scale; neural mechanosensitivity, as assessed using the passive straight-leg raise (SLR) test; and amount of spinal mobility in flexion, as measured using the finger-to-floor distance (FFD) test. The intragroup comparison indicated a significant improvement in all variables in the TG (Pperceived pain, spinal mobility in flexion, hip flexion during the passive SLR test, and subjects' full height. Future studies should include women and should evaluate the long-term results. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  15. Fel d 1-derived synthetic peptide immuno-regulatory epitopes show a long-term treatment effect in cat allergic subjects.

    Science.gov (United States)

    Couroux, P; Patel, D; Armstrong, K; Larché, M; Hafner, R P

    2015-05-01

    Cat-PAD, the first in a new class of synthetic peptide immuno-regulatory epitopes (SPIREs), was shown to significantly improve rhinoconjunctivitis symptoms in subjects with cat allergy up to 1 year after the start of a short course of treatment. To evaluate the long-term effects of Cat-PAD on rhinoconjunctivitis symptoms following standardized allergen challenge 2 years after treatment. In a randomized, double-blind, placebo-controlled, parallel group study, subjects were exposed to cat allergen in an environmental exposure chamber (EEC) before and after treatment with two regimens of Cat-PAD (either eight doses of 3 nmol or four doses of 6 nmol) given intradermally over a 3-month period. In this follow-up study, changes from baseline in rhinoconjunctivitis symptoms were reassessed 2 years after the start of treatment. The primary endpoint showed a mean reduction in total rhinoconjunctivitis symptom scores of 3.85 units in the 4 × 6 nmol Cat-PAD group compared to placebo 2 years after the start of treatment (P = 0.13), and this difference was statistically significant in the secondary endpoint at the end of day 4 when the cumulative allergen challenge was greatest (P = 0.02). Consistent reductions in nasal symptoms of between 2 and 3 units were observed for 4 × 6 nmol Cat-PAD compared to placebo between the 2 and 3 h time points on days 1-4 of EEC challenge at 2 years (P Cat-PAD. This study is the first to provide evidence of a long-term therapeutic effect with this new class of SPIREs. © 2015 The Authors. Clinical & Experimental Allergy Published by John Wiley & Sons Ltd.

  16. Middle-Term Dietary Supplementation with Red Yeast Rice Plus Coenzyme Q10 Improves Lipid Pattern, Endothelial Reactivity and Arterial Stiffness in Moderately Hypercholesterolemic Subjects.

    Science.gov (United States)

    Cicero, Arrigo F G; Morbini, Martino; Rosticci, Martina; D''Addato, Sergio; Grandi, Elisa; Borghi, Claudio

    2016-01-01

    The aim of our study was to investigate whether treatment with red yeast rice added with Coenzyme Q10 is associated with changes in endothelial function and arterial stiffness. This double blind, placebo-controlled, randomized clinical trial was carried out on 40 non-smoker moderately hypercholesterolemic subjects (ClinicalTrial.gov ID NCT02492464). After 4 weeks of diet and physical activity, patients were allocated to treatment with placebo or with an active product containing 10 mg monacolins and 30 mg Coenzyme Q10, to be assumed for 6 months. Endothelial reactivity and arterial stiffness have been measured through the validated Vicorder® device. During monacolin treatment, patients experienced a more favorable percentage change in low density lipoprotein (LDL)-cholesterol (after monacolin treatment: -26.3%; after placebo treatment: +3.4%, p < 0.05). Endothelial reactivity (pulse volume displacement after monacolin treatment: +6.0%; after placebo treatment: -0.3%, p < 0.05), and arterial stiffness (pulse wave velocity (PWV) after monacolin treatment: -4.7%; after placebo: +1.1%, p < 0.05) also significantly improved only after monacolin treatment. The long-term assumption of the tested dietary supplement is associated with an improvement in LDL-cholesterolemia, endothelial reactivity and PWV in moderately hypercholesterolemic subjects. © 2016 S. Karger AG, Basel.

  17. Short-Term Intra-Subject Variation in Exhaled Volatile Organic Compounds (VOCs in COPD Patients and Healthy Controls and Its Effect on Disease Classification

    Directory of Open Access Journals (Sweden)

    Christopher Phillips

    2014-05-01

    Full Text Available Exhaled volatile organic compounds (VOCs are of interest for their potential to diagnose disease non-invasively. However, most breath VOC studies have analyzed single breath samples from an individual and assumed them to be wholly consistent representative of the person. This provided the motivation for an investigation of the variability of breath profiles when three breath samples are taken over a short time period (two minute intervals between samples for 118 stable patients with Chronic Obstructive Pulmonary Disease (COPD and 63 healthy controls and analyzed by gas chromatography and mass spectroscopy (GC/MS. The extent of the variation in VOC levels differed between COPD and healthy subjects and the patterns of variation differed for isoprene versus the bulk of other VOCs. In addition, machine learning approaches were applied to the breath data to establish whether these samples differed in their ability to discriminate COPD from healthy states and whether aggregation of multiple samples, into single data sets, could offer improved discrimination. The three breath samples gave similar classification accuracy to one another when evaluated separately (66.5% to 68.3% subjects classified correctly depending on the breath repetition used. Combining multiple breath samples into single data sets gave better discrimination (73.4% subjects classified correctly. Although accuracy is not sufficient for COPD diagnosis in a clinical setting, enhanced sampling and analysis may improve accuracy further. Variability in samples, and short-term effects of practice or exertion, need to be considered in any breath testing program to improve reliability and optimize discrimination.

  18. Study of advanced fuel system concepts for commercial aircraft and engines

    Science.gov (United States)

    Versaw, E. F.; Brewer, G. D.; Byers, W. D.; Fogg, H. W.; Hanks, D. E.; Chirivella, J.

    1983-01-01

    The impact on a commercial transport aircraft of using fuels which have relaxed property limits relative to current commercial jet fuel was assessed. The methodology of the study is outlined, fuel properties are discussed, and the effect of the relaxation of fuel properties analyzed. Advanced fuel system component designs that permit the satisfactory use of fuel with the candidate relaxed properties in the subject aircraft are described. The two fuel properties considered in detail are freezing point and thermal stability. Three candidate fuel system concepts were selected and evaluated in terms of performance, cost, weight, safety, and maintainability. A fuel system that incorporates insulation and electrical heating elements on fuel tank lower surfaces was found to be most cost effective for the long term.

  19. Long-term postpartum anxiety and depression-like behavior in mother rats subjected to maternal separation are ameliorated by palatable high fat diet.

    Science.gov (United States)

    Maniam, Jayanthi; Morris, Margaret J

    2010-03-17

    While the effects of maternal separation on pups are well studied, the impact on dams has attracted little attention. The consumption of palatable food is known to dampen stress responses in animals, and emotions influence food choice in humans. Here we examined the early- and long-term impacts of maternal separation on behavioral profile of the dams, and the effects of palatable cafeteria high-fat diet (HFD). After littering, Sprague-Dawley female rats were subjected to prolonged separation, S180 (180 min) or brief separation, S15 (15 min/day) from postnatal days (PND) 2-14. At 4 weeks postpartum, half the dams were assigned to HFD. Anxiety and depression-like behaviors were assessed pre- and post-diet. Compared to S15 dams, S180 dams consuming chow demonstrated increased anxiety and depression-like behaviors assessed by elevated plus maze (EPM) and forced swim (FST) tests, respectively. These behavioral deficits were observed at 4 weeks, and persisted until 17 weeks postpartum. The S180 dams also had increased plasma corticosterone concentration compared to S15 dams, which coincided with increased hypothalamic CRH mRNA and reduced hippocampal GR mRNA expression, suggesting possible dysregulation of hypothalamic-pituitary-adrenal axis activity. Interestingly, continuous provision of HFD improved the behavioral deficits observed in S180 dams with significant reduction of hypothalamic CRH mRNA expression. These data are the first to describe long-term detrimental behavioral impacts of separation in dams, suggesting this may provide a model of postpartum depression. Moreover, they support the notion of long-term beneficial effects of 'comfort food' on stress responses. Crown Copyright 2009. Published by Elsevier B.V. All rights reserved.

  20. 49 CFR 175.310 - Transportation of flammable liquid fuel; aircraft only means of transportation.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Transportation of flammable liquid fuel; aircraft... Material § 175.310 Transportation of flammable liquid fuel; aircraft only means of transportation. (a) When... racks or slings. (c) Flammable liquid fuels may be carried on a cargo aircraft, subject to the following...

  1. Meet your Aircraft Quiz

    Science.gov (United States)

    1995-01-01

    This quiz is designed to help a pilot meet his or her aircraft. Although no attempt is made to cover in depth all of the information contained in the typical Pilot's Operating Handbook (POH), Owner's Manual (OM), or Aircraft Flight Manual (AFM), the ...

  2. DEVELOPMENT OF AIRCRAFT,

    Science.gov (United States)

    Criteria of effectiveness of aviation; Development of aviation in the period 1918-1939; Main factors of the progress of speed; Cause of changes of main...factors of combat efficiency of aircraft; Equation of state of production of aircraft; Development of aviation 1939-1959; and Development of one-shot winged and ballistic vehicles.

  3. Contextualising aircraft maintenance documentation

    NARCIS (Netherlands)

    Koornneef, H.; Verhagen, W.J.C.; Curran, Ricky

    2017-01-01

    The use of documentation for task support in aircraft line maintenance is still mostly paper-based, which is slow, burdensome and prone to error. This paper provides an overview of the issues associated with the use of paper-based documentation in aircraft line maintenance and describes the

  4. Aircraft operations management manual

    Science.gov (United States)

    1992-01-01

    The NASA aircraft operations program is a multifaceted, highly diverse entity that directly supports the agency mission in aeronautical research and development, space science and applications, space flight, astronaut readiness training, and related activities through research and development, program support, and mission management aircraft operations flights. Users of the program are interagency, inter-government, international, and the business community. This manual provides guidelines to establish policy for the management of NASA aircraft resources, aircraft operations, and related matters. This policy is an integral part of and must be followed when establishing field installation policy and procedures covering the management of NASA aircraft operations. Each operating location will develop appropriate local procedures that conform with the requirements of this handbook. This manual should be used in conjunction with other governing instructions, handbooks, and manuals.

  5. Research on aircraft emissions. Need for future work

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, A. [German Aerospace Establishment, Cologne (Germany). Transport Research Div.

    1997-12-31

    Reflecting the present status of the research on aircraft emissions and their impacts upon the atmosphere, task-fields for a work programme for the research on aircraft emissions can be derived. Most important measures are to support the efforts to define adequate reduction measures, and (with highest priority) scenario-writing for the long-term development in aircraft emissions, to be able to include into the decision making process the aspect of in-time-reaction against unwanted future. Besides that, a steady monitoring of global aircraft emissions will be necessary. (author) 5 refs.

  6. Smart fastener technology for aging aircraft

    Science.gov (United States)

    Schoess, Jeffrey N.; Paul, Clare A.

    1995-04-01

    Hidden and inaccessible corrosion in aircraft structures is the number 1 logistics problem for the Air Force, with an estimated maintenance cost of greater than one billion dollars per year. The smart aircraft fastener evaluation (SAFE) system is being developed to detect and characterize corrosion factors in hidden locations of aircraft structures. The SAFE concept is a novel `in-situ' measurement approach that measures and autonomously records several environmental factors (i.e., pH, temperature, chloride) associated with corrosion. The SAFE system integrated an electrochemical-based microsensor array directly into the aircraft structure to measure the evidence of active corrosion as an in-situ measurement without reducing aircraft structural integrity. The long term-payoff for the SAFE system will be in predictive maintenance for fixed and rotary wing aircraft structures, industrial tanks, and fugitive emissions applications such as control valves, chemical pipeline vessels, and industrial boilers. Predictive maintenance capability, service and repair will replace the current practice of scheduled maintenance to substantially reduce operational costs.

  7. The effects of long-term daily folic acid and vitamin B12 supplementation on genome-wide DNA methylation in elderly subjects.

    Science.gov (United States)

    Kok, Dieuwertje E G; Dhonukshe-Rutten, Rosalie A M; Lute, Carolien; Heil, Sandra G; Uitterlinden, André G; van der Velde, Nathalie; van Meurs, Joyce B J; van Schoor, Natasja M; Hooiveld, Guido J E J; de Groot, Lisette C P G M; Kampman, Ellen; Steegenga, Wilma T

    2015-01-01

    Folate and its synthetic form folic acid function as donor of one-carbon units and have been, together with other B-vitamins, implicated in programming of epigenetic processes such as DNA methylation during early development. To what extent regulation of DNA methylation can be altered via B-vitamins later in life, and how this relates to health and disease, is not exactly known. The aim of this study was to identify effects of long-term supplementation with folic acid and vitamin B12 on genome-wide DNA methylation in elderly subjects. This project was part of a randomized, placebo-controlled trial on effects of supplemental intake of folic acid and vitamin B12 on bone fracture incidence (B-vitamins for the PRevention Of Osteoporotic Fractures (B-PROOF) study). Participants with mildly elevated homocysteine levels, aged 65-75 years, were randomly assigned to take 400 μg folic acid and 500 μg vitamin B12 per day or a placebo during an intervention period of 2 years. DNA was isolated from buffy coats, collected before and after intervention, and genome-wide DNA methylation was determined in 87 participants (n = 44 folic acid/vitamin B12, n = 43 placebo) using the Infinium HumanMethylation450 BeadChip. After intervention with folic acid and vitamin B12, 162 (versus 14 in the placebo group) of the 431,312 positions were differentially methylated as compared to baseline. Comparisons of the DNA methylation changes in the participants receiving folic acid and vitamin B12 versus placebo revealed one single differentially methylated position (cg19380919) with a borderline statistical significance. However, based on the analyses of differentially methylated regions (DMRs) consisting of multiple positions, we identified 6 regions that differed statistically significantly between the intervention and placebo group. Pronounced changes were found for regions in the DIRAS3, ARMC8, and NODAL genes, implicated in carcinogenesis and early embryonic development

  8. Long-term incidence of female-specific cancer after bariatric surgery or usual care in the Swedish Obese Subjects Study.

    Science.gov (United States)

    Anveden, Åsa; Taube, Magdalena; Peltonen, Markku; Jacobson, Peter; Andersson-Assarsson, Johanna C; Sjöholm, Kajsa; Svensson, Per-Arne; Carlsson, Lena M S

    2017-05-01

    To examine the long-term effects of bariatric surgery on female-specific cancer in women with obesity. The prospective, matched Swedish Obese Subjects (SOS) study was designed to examine outcomes after bariatric surgery. This study includes 1420 women from the SOS cohort that underwent bariatric surgery and 1447 contemporaneously matched controls who received conventional obesity treatment. Age was 37-60years and BMI was ≥38kg/m2. Information on cancer events was obtained from the Swedish National Cancer Registry. Median follow-up time was 18.1years (interquartile range 14.8-20.9years, maximum 26years). This study is registered with ClinicalTrials.gov, NCT01479452. Bariatric surgery was associated with reduced risk of overall cancer (hazard ratio=0.71; 95% CI 0.59-0.85; pbariatric surgery was associated with reduced risk of endometrial cancer (hazard ratio=0.56: 95% CI 0.35-0.89; p=0.014). In this long-term study, bariatric surgery was associated with reduced risk of female-specific cancer, especially in women with hyperinsulinemia at baseline. This project was supported by grants from the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health under Award Number R01DK105948 (the content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health), the Swedish Research Council K2013-99X-22279-01, K2013-54X-11285-19, Sahlgrenska University Hospital ALF research grant and Swedish Diabetes Foundation. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Influence of Blood Pressure and Other Clinical Variables on Long-Term Mortality in a Cohort of Elderly Subjects with Type 2 Diabetes.

    Science.gov (United States)

    Tessier, Daniel M; Meneilly, Graydon S; Moleski, Luc; Trottier, Lise; Lanthier, Luc

    2016-02-01

    Diabetes mellitus and high blood pressure (HBP) are commonly associated conditions in the elderly population. An effect of treatments, biologic and anthropometric variables on long-term mortality is unknown in this population. To determine the prevalence of HBP control in a sample of elderly patients with type 2 diabetes with office blood pressure (BP) readings and ambulatory blood pressure monitoring (ABPM) and evaluate the influence of BP, anthropometric and laboratory variables on long term mortality. Cohort study in patients living at home in the area of Sherbrooke, ≥65 years old, receiving reimbursement for antidiabetic medication. The study included medical history, 2 sets of BP measurements, 2 24-hour urinary collections for microalbuminuria, 1 24-hour ABPM, blood level of creatinine and glycosylated hemoglobin. Charts were reanalyzed 8 years later for analysis of cardiovascular and total mortality cases. 198 patients were initially recruited. By history, 83% of the subjects had diagnoses and treatments for high blood pressure. In multivariate analysis, factors associated with an 8-year increased risk for cardiovascular mortality were creatinine ≥84 µmol/L, office seated systolic blood pressure ≤130 and diastolic BP ≤67.6 over 24 hours. Factors associated with total mortality were lower waist circumference, serum creatinine ≥84 and diastolic BP ≤67.6 over 24 hours. Lower systolic and diastolic BP (office and ABPM), lower waist circumference and higher creatinine values are associated with an increased mortality risk. This suggests that a lower BP, declining kidney function and frailty are factors associated with this observation. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

  10. Predicting Visibility of Aircraft

    Science.gov (United States)

    Watson, Andrew; Ramirez, Cesar V.; Salud, Ellen

    2009-01-01

    Visual detection of aircraft by human observers is an important element of aviation safety. To assess and ensure safety, it would be useful to be able to be able to predict the visibility, to a human observer, of an aircraft of specified size, shape, distance, and coloration. Examples include assuring safe separation among aircraft and between aircraft and unmanned vehicles, design of airport control towers, and efforts to enhance or suppress the visibility of military and rescue vehicles. We have recently developed a simple metric of pattern visibility, the Spatial Standard Observer (SSO). In this report we examine whether the SSO can predict visibility of simulated aircraft images. We constructed a set of aircraft images from three-dimensional computer graphic models, and measured the luminance contrast threshold for each image from three human observers. The data were well predicted by the SSO. Finally, we show how to use the SSO to predict visibility range for aircraft of arbitrary size, shape, distance, and coloration. PMID:19462007

  11. Aircraft Engine Emissions Estimator

    Science.gov (United States)

    1985-11-01

    Protection Agency, " Control of Air Pollution From Aircraft and Aircraft Engines," 43 FR 12615, March 24, Vq7. 51 ~~SL% 12. Souza, A.F. F-100 Afterburner...R.G. Technical Support Report-Aircraft Emissions Factors, USEPA Office of Mobile Source Air Pollution Control , Ann Arbor, MI, March 1977. 14. Souza, A.F...STAVILITY CATEGOUY 6 WIND SPELU (METERS/SECOND) 1600 WINU DIRECTION TAILWIN) TEMPERATURa " (F) 38.0O MIXING DEPT" (METLRS) l1.o00

  12. SOLAR AIRCRAFT DESIGN

    OpenAIRE

    Rahmati, Sadegh; GHASED, Amir

    2015-01-01

    Abstract. Generally domain Aircraft uses conventional fuel. These fuel having limited life, high cost and pollutant. Also nowadays price of petrol and other fuels are going to be higher, because of scarcity of those fuels. So there is great demand of use of non-exhaustible unlimited source of energy like solar energy. Solar aircraft is one of the ways to utilize solar energy. Solar aircraft uses solar panel to collect the solar radiation for immediate use but it also store the remaining part ...

  13. Tropospheric sampling with aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Daum, P.H.; Springston, S.R.

    1991-03-01

    Aircraft constitute a unique environment which places stringent requirements on the instruments used to measure the concentrations of atmospheric trace gases and aerosols. Some of these requirements such as minimization of size, weight, and power consumption are general; others are specific to individual techniques. This review presents the basic principles and considerations governing the deployment of trace gas and aerosol instrumentation on an aircraft. An overview of common instruments illustrates these points and provides guidelines for designing and using instruments on aircraft-based measurement programs.

  14. Aircraft electromagnetic compatibility

    Science.gov (United States)

    Clarke, Clifton A.; Larsen, William E.

    1987-06-01

    Illustrated are aircraft architecture, electromagnetic interference environments, electromagnetic compatibility protection techniques, program specifications, tasks, and verification and validation procedures. The environment of 400 Hz power, electrical transients, and radio frequency fields are portrayed and related to thresholds of avionics electronics. Five layers of protection for avionics are defined. Recognition is given to some present day electromagnetic compatibility weaknesses and issues which serve to reemphasize the importance of EMC verification of equipment and parts, and their ultimate EMC validation on the aircraft. Proven standards of grounding, bonding, shielding, wiring, and packaging are laid out to help provide a foundation for a comprehensive approach to successful future aircraft design and an understanding of cost effective EMC in an aircraft setting.

  15. Aircraft electromagnetic compatibility

    Science.gov (United States)

    Clarke, Clifton A.; Larsen, William E.

    1987-01-01

    Illustrated are aircraft architecture, electromagnetic interference environments, electromagnetic compatibility protection techniques, program specifications, tasks, and verification and validation procedures. The environment of 400 Hz power, electrical transients, and radio frequency fields are portrayed and related to thresholds of avionics electronics. Five layers of protection for avionics are defined. Recognition is given to some present day electromagnetic compatibility weaknesses and issues which serve to reemphasize the importance of EMC verification of equipment and parts, and their ultimate EMC validation on the aircraft. Proven standards of grounding, bonding, shielding, wiring, and packaging are laid out to help provide a foundation for a comprehensive approach to successful future aircraft design and an understanding of cost effective EMC in an aircraft setting.

  16. Unmanned Aircraft Systems - Orthoimagery

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The USGS National Unmanned Aircraft Systems (UAS) Project Office utilizes UAS technology for collecting remote sensing data on a local scale. Typical UAS projects...

  17. Depreciation of aircraft

    Science.gov (United States)

    Warner, Edward P

    1922-01-01

    There is a widespread, and quite erroneous, impression to the effect that aircraft are essentially fragile and deteriorate with great rapidity when in service, so that the depreciation charges to be allowed on commercial or private operation are necessarily high.

  18. Aircraft Depainting Technology

    National Research Council Canada - National Science Library

    Kozol, Joseph

    1999-01-01

    ... of aircraft and component stripping at various levels of maintenance. Under this program, the Navy pursued development of non-HAP chemical paint strippers as alternatives for methylene chloride based strippers...

  19. Essentials of aircraft armaments

    CERN Document Server

    Kaushik, Mrinal

    2017-01-01

    This book aims to provide a complete exposure about armaments from their design to launch from the combat aircraft. The book details modern ammunition and their tactical roles in warfare. The proposed book discusses aerodynamics, propulsion, structural as well as navigation, control, and guidance of aircraft armament. It also introduces the various types of ammunition developed by different countries and their changing trends. The book imparts knowledge in the field of design, and development of aircraft armaments to aerospace engineers and covers the role of the United Nations in peacekeeping and disarmament. The book will be very useful to researchers, students, and professionals working in design and manufacturing of aircraft armaments. The book will also serve air force and naval aspirants, and those interested in working on defence research and developments organizations. .

  20. Aircraft Fire Protection Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Navy Aircraft Protection Laboratory provides complete test support for all Navy air vehicle fire protection systems.The facility allows for the simulation of a...

  1. Short-term effect of topical antiglaucoma medication on tear-film stability, tear secretion, and corneal sensitivity in healthy subjects

    Directory of Open Access Journals (Sweden)

    Pillunat LE

    2011-04-01

    Full Text Available Naim Terai, Matthias Müller-Holz, Eberhard Spoerl, Lutz E PillunatDepartment of Ophthalmology, Carl Gustav Carus University Hospital, Dresden, GermanyBackground: The purpose of this study was to investigate the short-term effect of topical antiglaucoma medication on tear-film stability, tear secretion, and corneal sensitivity in healthy subjects.Methods: In this prospective, double-blind crossover trial, break-up time and basal secretion (Jones test were measured 60 minutes before, and 30, 60, and 90 minutes after topical antiglaucoma drop application in 30 healthy subjects. Corneal sensitivity was measured 60 minutes before, and five, 10, and 15 minutes after drop application using a Cochet–Bonnet esthesiometer.Results: Reduction of break-up time in the latanoprost group was -23.8% after 30 minutes (P = 0.21, -26.7% after 60 minutes (P = 0.03 and -51.4% after 90 minutes (P ≤ 0.003, which was statistically significant. Reduction of break-up time in all other treatment groups was not statistically significant. The Jones test revealed a significant reduction of basal secretion after application of brimonidine (-17.8%, P = 0.002; -22.5%, P< 0.001; -30.5%, P < 0.001, followed by apraclonidine (-10%, P = 0.06; -20.1%, P = 0.02; -22.1%, P = 0.002, latanoprost (-2.4%, P = 0.64; -18.6%, P = 0.001; -20.1%, P = 0.001 and dorzolamide (-0.5%, P = 0.9; 14.3%, P = 0.018; -17.3%, P = 0.004 at 30, 60, and 90 minutes after drop application. Reduction of basal secretion in all other treatment groups was not statistically significant.Conclusion: Latanoprost showed the most statistically significant reduction in break-up time, and brimonidine showed the most significant reduction in basal secretion of all the glaucoma medications used in this study. In conclusion, our data may be helpful for treatment decisions in glaucoma patients who also suffer from ocular surface problems.Keywords: tear-film, tear secretion, corneal sensitivity, antiglaucoma medication

  2. Effects of short-term exercise in the heat on thermoregulation, blood parameters, sweat secretion and sweat composition of tropic-dwelling subjects.

    Science.gov (United States)

    Saat, Mohamed; Sirisinghe, Roland Gamini; Singh, Rabindarjeet; Tochihara, Yutaka

    2005-09-01

    This study investigates the effects of a short-term aerobic training program in a hot environment on thermoregulation, blood parameters, sweat secretion and composition in tropic-dwellers who have been exposed to passive heat. Sixteen healthy Malaysian-Malay male volunteers underwent heat acclimation (HA) by exercising on a bicycle ergometer at 60% of VO2max for 60 min each day in a hot environment (Ta: 31.1+/-0.1 degrees C, rh: 70.0+/-4.4%) for 14 days. All parameters mentioned above were recorded on Day 1 and at the end of HA (Day 16). On these two days, subjects rested for 10 min, then cycled at 60% of VO2max for 60 min and rested again for 20 min (recovery) in an improvised heat chamber. Rectal temperature (Tre), mean skin temperature (Tsk) heart rate (HR), ratings of perceived exertion (RPE), thermal sensation (TS), local sweat rate and percent dehydration were recorded during the test. Sweat concentration was analysed for sodium [Na+]sweat and potassium. Blood samples were analysed for biochemical changes, electrolytes and hematologic indices. Urine samples were collected before and after each test and analysed for electrolytes.After the period of acclimation the percent dehydration during exercise significantly increased from 1.77+/-0.09% (Day 1) to 2.14+/-0.07% (Day 16). Resting levels of hemoglobin, hematocrit and red blood cells decreased significantly while [Na+]sweat increased significantly. For Tre and Tsk there were no differences at rest. Tre, HR, RPE, TS, plasma lactate concentration, hemoglobin and hematocrit at the 40th min of exercise were significantly lower after the period of acclimation but mean corpuscular hemoglobin and serum osmolality were significantly higher while no difference was seen in [Na+]sweat and Tsk. It can be concluded that tropic-dwelling subjects, although exposed to prolonged passive heat exposure, were not fully heat acclimatized. To achieve further HA, they should gradually expose themselves to exercise-heat stress in a

  3. Long-term safety of oral nucleos(t)ide analogs for patients with chronic hepatitis B: A cohort study of 53,500 subjects.

    Science.gov (United States)

    Wong, Grace Lai-Hung; Tse, Yee-Kit; Wong, Vincent Wai-Sun; Yip, Terry Cheuk-Fung; Tsoi, Kelvin Kam-Fai; Chan, Henry Lik-Yuen

    2015-09-01

    Widespread and long-term use of oral nucleos(t)ide analogs (NAs) to treat chronic hepatitis B (CHB) brings about safety data in a real-life setting. We aimed to determine the risks of renal and bone side effects in patients receiving or who have received NAs as CHB treatment. A territory-wide cohort study using the database from Hospital Authority, the major provider of medical services in Hong Kong, was conducted. We identified CHB patients by International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes, diagnosed between 2000 and 2012. The primary events were renal (incident renal failure and renal replacement therapy [RRT]) and bone events (incident hip, vertebral, and all fractures). A 3-year landmark analysis was used to evaluate the relative risk of primary outcome in patients with or without NA treatment. A total of 53,500 CHB patients (46,454 untreated and 7,046 treated), who were event free for 3 years, were included in the analysis. At a median follow-up of 4.9 years, chronic renal failure, RRT, all fractures, hip fractures, and vertebral fractures occurred in 0.6%, 0.2%, 0.7%, 0.1%, and 0.1% of untreated subjects and 1.4%, 0.7%, 1.3%, 0.2%, and 0.2% of treated subjects. After propensity score weighting, NA therapy did not increase the risk of any of the events (hazard ratios [HRs] ranged from 0.79 to 1.31; P = 0.225-0.887). Exposure to nucleotide analogues, compared with nucleoside analogs, increased the risk of hip fracture (HR = 5.69; 95% confidence interval: 1.98-16.39; P = 0.001), but not other events (HR = 0.58-1.44; P = 0.202-0.823). NA treatment does not increase the risk of renal and bone events in general. Nucleotide analogs may increase the risk of hip fracture, but the overall event rate is low. © 2015 by the American Association for the Study of Liver Diseases.

  4. Aircraft Survivability. Summer 2011

    Science.gov (United States)

    2011-01-01

    aircraft in Mombasa, Kenya, in 2002 and a DHL cargo aircraft in Baghdad, Iraq, in 2003, the threat is not limited to military operations, but is of...Government/ Customer Iterate Based on Changes Over the Life of the A/C Describe Performance Requirements Figure 3 Value of Impact Capability Figure 2 FSC... customer describing their performance requirements, identifying probable mission scenarios, prioritizing possible impact conditions, and setting

  5. Aircraft engine noise

    Science.gov (United States)

    Kennepohl, F.

    An overview of the main aircraft engine noise sources is given. Special emphasis is devoted to turbomachinery/rotor noise, which plays an important role in all engine concepts appropriate to regional aircraft, such as turbofans, propellers, or new propfan engine concepts. The noise generating mechanisms, including propagation within the engine, and calculation methods used are described. Noise reduction methods are considered, with emphasis on cutoff design of turbomachines. Some noise features of counter rotating propellers and swept rotor blades are mentioned.

  6. Impact of short-term high-fat feeding and insulin-stimulated FGF21 levels in subjects with low birth weight and controls.

    Science.gov (United States)

    Vienberg, Sara G; Brøns, Charlotte; Nilsson, Emma; Astrup, Arne; Vaag, Allan; Andersen, Birgitte

    2012-07-01

    Fibroblast growth factor 21 (FGF21) is a metabolic factor involved in glucose and lipid metabolism. However, little is known about the physiological role of FGF21 during a dietary challenge in humans. Twenty healthy low birth weight (LBW) with known risk of type 2 diabetes and 26 control (normal birth weight (NBW)) young men were subjected to 5 days of high-fat (HF) overfeeding (+50%). Basal and clamp insulin-stimulated serum FGF21 levels were examined before and after the diet, and FGF21 mRNA expression was measured in muscle and fat biopsies respectively. Five days of HF overfeeding diet significantly (Pincreased fasting serum FGF21 levels in both the groups (Pinsulin infusion additionally increased serum FGF21 levels to a similar extent in both the groups. Basal mRNA expression of FGF21 in muscle was near the detection limit and not present in fat in both the groups before and after the dietary challenge. However, insulin significantly (Pincreased FGF21 mRNA in both muscle and fat in both the groups during both diets. Short-term HF overfeeding markedly increased serum FGF21 levels in healthy young men with and without LBW but failed to increase muscle or fat FGF21 mRNA levels. This suggests that the liver may be responsible for the rise of serum FGF21 levels during overfeeding. In contrast, the increase in serum FGF21 levels during insulin infusion may arise from increased transcription in muscle and fat. We speculate that increased serum FGF21 levels during HF overfeeding may be a compensatory response to increase fatty acid oxidation and energy expenditure.

  7. Long-term test-retest reliability of resting-state networks in healthy elderly subjects and with amnestic mild cognitive impairment patients.

    Science.gov (United States)

    Blautzik, Janusch; Keeser, Daniel; Berman, Albert; Paolini, Marco; Kirsch, Valerie; Mueller, Sophia; Coates, Ute; Reiser, Maximilian; Teipel, Stefan J; Meindl, Thomas

    2013-01-01

    The investigation of cerebral resting-state networks (RSNs) by functional magnetic resonance imaging (fMRI) is a promising tool for the early diagnosis and follow-up of neuropsychiatric and neurodegenerative disorders like Alzheimer's disease (AD). In this context, the determination of inter-session reliability of these networks is crucial. However, data on network reliability in healthy elderly subjects is rare and does not exist for patients with amnestic mild cognitive impairment (aMCI), a prodromal stage of AD. Therefore, the aim of this study was to investigate the long-term test-retest reliability of RSNs in both groups. Twelve healthy controls (HC) and 13 aMCI patients underwent resting-state fMRI and neuropsychological testing (CERAD test battery) twice, at baseline and after 13-16 months. Resting-state fMRI data was decomposed into independent components using independent component analysis. Inter-session test-retest reliability of the resulting RSNs was determined by calculating voxel-wise intra-class correlation coefficients. Overall test-retest reliability of corresponding RSNs was moderate to high in both groups, but significantly higher in the HC group compared to the aMCI group (p < 0.001), while the cognitive performance within the CERAD test battery remained stable over time in either group. Most reliable RSNs derived from the HC group and were associated with sensory and motor as well as higher order cognitive and the default-mode function. Particularly low reliability was found in basal frontal regions, which are known to be prone to susceptibility-induced noise. We conclude that stable RSNs may represent healthy aging, whereas decreased RSN reliability may indicate progressive neuro-functional alterations before the actual manifestation of clinical symptoms.

  8. The effect of exogenous spermidine concentration on polyamine metabolism and salt tolerance in zoysiagrass (Zoysia japonica Steud subjected to short-term salinity stress

    Directory of Open Access Journals (Sweden)

    Shucheng Li

    2016-08-01

    Full Text Available Salt stress, and particularly short-term salinity stress, is one of the most serious abiotic factors limiting plant survival and growth in China. It has been established that exogenous spermidine (Spd stimulats tolerance to salt stress in plants. In the present study, two cultivars that are typically grown in China were used. The two zoysiagrass cultivars, exhibiting a sensitive ( cv. Z081 or tolerant ( cv. Z057 salt stress adaptation ability, were subjected to 200 mM salt stress and treated with different exogenous Spd concentrations for 8 days. Polyamine (Put, Spd and Spm contents and polyamine metabolic enzyme (ADC, ODC, SAMDC, PAO and DAO, malondialdehyde (MDA, H2O2 and antioxidant enzyme activities (superoxide dismutase, catalase, and peroxidase were measured. The results showed that salt stress induced increases in Spd and Spm contents and the activity of ornithine decarboxylase (ODC, S-adenosylmethionine decarboxylase (SAMDC and diamine oxidase (DAO in both cultivars. Exogenous Spd application did not compromise polyamine contents through the regulation of polyamine-degrading enzymes, and an increase in PA synthesis enzymes was observed during the experiment. The application resulted in a tendency for the Spd and Spm contents and the activities of ODC, S-adenosylmethionine decarboxylase (SAMDC, DAO, and antioxidant enzymes to first increase and then decrease in both cultivars with an increase in the exogenous Spd concentration. H2O2 and MDA significantly decreased in both cultivars treated with Spd. With an increase in the exogenous Spd concentration, the Spd + Spm level scores showed positive correlations with polyamine synthesis enzymes (ADC, SAMDC, DAO, antioxidant enzymes (SOD, POD, CAT, while showing negative correlations with H2O2 and MDA in both cultivars.

  9. Long term effectiveness of once-daily unboosted atazanavir plus abacavir/lamivudine as a switch strategy in subjects with virological suppression

    Directory of Open Access Journals (Sweden)

    Josep M Llibre

    2014-11-01

    (3. Effectiveness data of ATV400+ABC/3TC as a switch strategy in clinical routine however are scant. Methods: We evaluated treatment outcomes of ATV400+ABC/3TC in pre-treated subjects in the EuroSIDA cohort with undetectable HIV-1 RNA, and previous ABC experience or assumed previous HLA B57*01 testing. We performed a time to loss of virologic response (TLOVR below 50 c/mL and a snapshot analysis at 48, 96 and 144 weeks. Virological failure (VF was defined as a confirmed plasma HIV-1 RNA >50 c/mL. Results: We included 258 subjects: 176 (68% male, median age 46 (IQR 41, 53 y, 225 (87.2% white, hepatitis virus co-infection 36%, median baseline CD4 at switch 540 cells (360, 700, time with VL≤ 50 c/mL 45 (24, 69 months. The median calendar year of switching was 2008 (2006, 2010. The 3rd drug in previous regimen was ATV/r in 70 (27.1%, other PI/r in 25 (9.7%, and other 163 (63.2%; 85 (32.9% had previously failed with a PI. The virological response at 48/96/144 weeks was, respectively, 89.5 [95% CI 85.1, 92.9]/88 [83.4, 91.7]/86.3% [81.6, 90.4] (TLOVR, composite endpoint failure or stop for any reason and the risk of VF was 8.3/7.6/7.6%. In the snapshot analysis HIV-RNA was below 50 c/mL in 72.5/65.9/51.6%, respectively, and >50 c/mL in 6.6/5.4/4.3%. Only 0.8/1.9/3.5% discontinued due to adverse events. There was a high rate of discontinuations due to other reasons or with VL missing in window. In a multivariate adjusted analysis, we observed an association between VF and nadir CD4 count (RH 0.60 [0.39, 0.93] per 100 cells higher, time with VL≤50 c/mL (RH 0.89 [0.81, 0.98] per 6 months longer and previous failure with a PI (3.04 [1.36, 6.80]. There was no association with gender, age, hepatitis virus co-infection, CD4 count at time of switching or third drug used in the previous regimen. Conclusions: A switch to ATV400+ABC/3TC in selected subjects with HIV-RNA below 50 c/mL is associated with relatively low rates of VF and discontinuation due to adverse events. Use

  10. B-52 Launch Aircraft in Flight

    Science.gov (United States)

    2001-01-01

    the development of parachute recovery systems used to recover the space shuttle solid rocket booster casings. It also supported eight orbiter (space shuttle) drag chute tests in 1990. In addition, the B-52 served as the air launch platform for the first six Pegasus space boosters. During its many years of service, the B-52 has undergone several modifications. The first major modification was made by North American Aviation (now part of Boeing) in support of the X-15 program. This involved creating a launch-panel-operator station for monitoring the status of the test vehicle being carried, cutting a large notch in the right inboard wing flap to accommodate the vertical tail of the X-15 aircraft, and installing a wing pylon that enables the B-52 to carry research vehicles and test articles to be air-launched/dropped. Located on the right wing, between the inboard engine pylon and the fuselage, this wing pylon was subjected to extensive testing prior to its use. For each test vehicle the B-52 carried, minor changes were made to the launch-panel operator's station. Built originally by the Boeing Company, the NASA B-52 is powered by eight Pratt & Whitney J57-19 turbojet engines, each of which produce 12,000 pounds of thrust. The aircraft's normal launch speed has been Mach 0.8 (about 530 miles per hour) and its normal drop altitude has been 40,000 to 45,000 feet. It is 156 feet long and has a wing span of 185 feet.

  11. Riveted Lap Joints in Aircraft Fuselage Design, Analysis and Properties

    CERN Document Server

    Skorupa, Andrzej

    2012-01-01

    Fatigue of the pressurized fuselages of transport aircraft is a significant problem all builders and users of aircraft have to cope with for reasons associated with assuring a sufficient lifetime and safety, and formulating adequate inspection procedures. These aspects are all addressed in various formal protocols for creating and maintaining airworthiness, including damage tolerance considerations. In most transport aircraft, fatigue occurs in lap joints, sometimes leading to circumstances that threaten safety in critical ways. The problem of fatigue of lap joints has been considerably enlarged by the goal of extending aircraft lifetimes. Fatigue of riveted lap joints between aluminium alloy sheets, typical of the pressurized aircraft fuselage, is the major topic of the present book. The richly illustrated and well-structured chapters treat subjects such as: structural design solutions and loading conditions for fuselage skin joints; relevance of laboratory test results for simple lap joint specimens to rive...

  12. Aircraft and background noise annoyance effects

    Science.gov (United States)

    Willshire, K. F.

    1984-01-01

    To investigate annoyance of multiple noise sources, two experiments were conducted. The first experiment, which used 48 subjects, was designed to establish annoyance-noise level functions for three community noise sources presented individually: jet aircraft flyovers, air conditioner, and traffic. The second experiment, which used 216 subjects, investigated the effects of background noise on aircraft annoyance as a function of noise level and spectrum shape; and the differences between overall, aircraft, and background noise annoyance. In both experiments, rated annoyance was the dependent measure. Results indicate that the slope of the linear relationship between annoyance and noise level for traffic is significantly different from that of flyover and air conditioner noise and that further research was justified to determine the influence of the two background noises on overall, aircraft, and background noise annoyance (e.g., experiment two). In experiment two, total noise exposure, signal-to-noise ratio, and background source type were found to have effects on all three types of annoyance. Thus, both signal-to-noise ratio, and the background source must be considered when trying to determine community response to combined noise sources.

  13. Composite structural materials. [fiber reinforced composites for aircraft structures

    Science.gov (United States)

    Ansell, G. S.; Loewy, R. G.; Wiberly, S. E.

    1981-01-01

    Physical properties of fiber reinforced composites; structural concepts and analysis; manufacturing; reliability; and life prediction are subjects of research conducted to determine the long term integrity of composite aircraft structures under conditions pertinent to service use. Progress is reported in (1) characterizing homogeneity in composite materials; (2) developing methods for analyzing composite materials; (3) studying fatigue in composite materials; (4) determining the temperature and moisture effects on the mechanical properties of laminates; (5) numerically analyzing moisture effects; (6) numerically analyzing the micromechanics of composite fracture; (7) constructing the 727 elevator attachment rib; (8) developing the L-1011 engine drag strut (CAPCOMP 2 program); (9) analyzing mechanical joints in composites; (10) developing computer software; and (11) processing science and technology, with emphasis on the sailplane project.

  14. Acute and long-term effects of Roux-en-Y gastric bypass on glucose metabolism in subjects with Type 2 diabetes and normal glucose tolerance

    DEFF Research Database (Denmark)

    Jørgensen, N B; Jacobsen, S H; Dirksen, C

    2012-01-01

    Our aim was to study the potential mechanisms responsible for the improvement in glucose control in Type 2 diabetes (T2D) within days after Roux-en-Y gastric bypass (RYGB). Thirteen obese subjects with T2D and twelve matched subjects with normal glucose tolerance (NGT) were examined during a liqu...

  15. Identification of Aircraft Hazards

    Energy Technology Data Exchange (ETDEWEB)

    K. Ashley

    2006-12-08

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2005 [DIRS 174235], Section 6.4.1). That determination was conservatively based upon limited knowledge of flight data in the area of concern and upon crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a monitored geologic repository (MGR) at Yucca Mountain, using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987 [DIRS 103124], Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. The intended use of this report is to provide inputs for further screening and analysis of identified aircraft hazards based upon the criteria that apply to Category 1 and Category 2 event sequence analyses as defined in 10 CFR 63.2 [DIRS 176544] (Section 4). The scope of this report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the repository at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (Section 7).

  16. IDENTIFICATION OF AIRCRAFT HAZARDS

    Energy Technology Data Exchange (ETDEWEB)

    K.L. Ashley

    2005-03-23

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in the ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2004, Section 6.4.1). That determination was conservatively based on limited knowledge of flight data in the area of concern and on crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a Monitored Geologic Repository (MGR) at Yucca Mountain using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987, Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. NUREG-0800 is being used here as a reference because some of the same considerations apply. The intended use of this report is to provide inputs for further screening and analysis of the identified aircraft hazards based on the criteria that apply to Category 1 and 2 event sequence analyses as defined in 10 CFR 63.2 (see Section 4). The scope of this technical report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the MGR at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (see Section 7).

  17. Life cycle cost analysis of aging aircraft airframe maintenance

    Science.gov (United States)

    Sperry, Kenneth Robert

    Scope and method of study. The purpose of this study was to examine the relationship between an aircraft's age and its annual airframe maintenance costs. Common life cycle costing methodology has previously not recognized the existence of this cost growth potential, and has therefor not determined the magnitude nor significance of this cost element. This study analyzed twenty-five years of DOT Form 41-airframe maintenance cost data for the Boeing 727, 737, 747 and McDonnell Douglas DC9 and DC-10 aircraft. Statistical analysis included regression analysis, Pearson's r, and t-tests to test the null hypothesis. Findings and conclusion. Airframe maintenance cost growth was confirmed to be increasing after an aircraft's age exceeded its designed service objective of approximately twenty-years. Annual airframe maintenance cost growth increases were measured ranging from 3.5% annually for a DC-9, to approximately 9% annually for a DC-10 aircraft. Average measured coefficient of determination between age and airframe maintenance, exceeded .80, confirming a strong relationship between cost: and age. The statistical significance of the difference between airframe costs sampled in 1985, compared to airframe costs sampled in 1998 was confirmed by t-tests performed on each subject aircraft group. Future cost forecasts involving aging aircraft subjects must address cost growth due to aging when attempting to model an aircraft's economic service life.

  18. AIRCRAFT MAINTENANCE HANGAR

    Directory of Open Access Journals (Sweden)

    GEAMBASU Gabriel George

    2017-05-01

    Full Text Available The paper presents the maintenance process that is done on an airplane, at a certain period of time, or after a number of flight hours or cycles and describes the checks performed behind each inspection. The first part of research describes the aircraft maintenance process that has to be done after an updated maintenance manual according with aircraft type, followed by a short introduction about maintenance hangar. The second part of the paper presents a hangar design with a foldable roof and walls, which can be folded or extended, over an airplane when a maintenance process is done, or depending on weather condition.

  19. Full-Scale Structural and NDI Validation Tests of Bonded Composite Doublers for Commercial Aircraft Applications

    Energy Technology Data Exchange (ETDEWEB)

    Roach, D.; Walkington, P.

    1999-02-01

    Composite doublers, or repair patches, provide an innovative repair technique which can enhance the way aircraft are maintained. Instead of riveting multiple steel or aluminum plates to facilitate an aircraft repair, it is possible to bond a single Boron-Epoxy composite doubler to the damaged structure. Most of the concerns surrounding composite doubler technology pertain to long-term survivability, especially in the presence of non-optimum installations, and the validation of appropriate inspection procedures. This report focuses on a series of full-scale structural and nondestructive inspection (NDI) tests that were conducted to investigate the performance of Boron-Epoxy composite doublers. Full-scale tests were conducted on fuselage panels cut from retired aircraft. These full-scale tests studied stress reductions, crack mitigation, and load transfer capabilities of composite doublers using simulated flight conditions of cabin pressure and axial stress. Also, structures which modeled key aspects of aircraft structure repairs were subjected to extreme tension, shear and bending loads to examine the composite laminate's resistance to disbond and delamination flaws. Several of the structures were loaded to failure in order to determine doubler design margins. Nondestructive inspections were conducted throughout the test series in order to validate appropriate techniques on actual aircraft structure. The test results showed that a properly designed and installed composite doubler is able to enhance fatigue life, transfer load away from damaged structure, and avoid the introduction of new stress risers (i.e. eliminate global reduction in the fatigue life of the structure). Comparisons with test data obtained prior to the doubler installation revealed that stresses in the parent material can be reduced 30%--60% through the use of the composite doubler. Tests to failure demonstrated that the bondline is able to transfer plastic strains into the doubler and that

  20. Small Aircraft Transportation System Concept and Technologies

    Science.gov (United States)

    Holmes, Bruce J.; Durham, Michael H.; Tarry, Scott E.

    2005-01-01

    This paper summarizes both the vision and the early public-private collaborative research for the Small Aircraft Transportation System (SATS). The paper outlines an operational definition of SATS, describes how SATS conceptually differs from current air transportation capabilities, introduces four SATS operating capabilities, and explains the relation between the SATS operating capabilities and the potential for expanded air mobility. The SATS technology roadmap encompasses on-demand, widely distributed, point-to-point air mobility, through hired-pilot modes in the nearer-term, and through self-operated user modes in the farther-term. The nearer-term concept is based on aircraft and airspace technologies being developed to make the use of smaller, more widely distributed community reliever and general aviation airports and their runways more useful in more weather conditions, in commercial hired-pilot service modes. The farther-term vision is based on technical concepts that could be developed to simplify or automate many of the operational functions in the aircraft and the airspace for meeting future public transportation needs, in personally operated modes. NASA technology strategies form a roadmap between the nearer-term concept and the farther-term vision. This paper outlines a roadmap for scalable, on-demand, distributed air mobility technologies for vehicle and airspace systems. The audiences for the paper include General Aviation manufacturers, small aircraft transportation service providers, the flight training industry, airport and transportation authorities at the Federal, state and local levels, and organizations involved in planning for future National Airspace System advancements.

  1. Long-term outcomes of bronchial thermoplasty in subjects with severe asthma: a comparison of 3-year follow-up results from two prospective multicentre studies

    Science.gov (United States)

    Laviolette, Michel; Cohn, Lauren; McEvoy, Charlene; Bansal, Sandeep; Shifren, Adrian; Khatri, Sumita; Grubb, G. Mark; McMullen, Edmund; Strauven, Racho; Kline, Joel N.

    2017-01-01

    Bronchial thermoplasty is an endoscopic therapy for severe asthma. The previously reported, randomised sham-controlled AIR2 (Asthma Intervention Research 2) trial showed a significant reduction in severe asthma exacerbations, emergency department visits and hospitalisations after bronchial thermoplasty. More “real-world” clinical outcome data is needed. This article compares outcomes in bronchial thermoplasty subjects with 3 years of follow-up from the ongoing, post-market PAS2 (Post-FDA Approval Clinical Trial Evaluating Bronchial Thermoplasty in Severe Persistent Asthma) study with those from the AIR2 trial. 279 subjects were treated with bronchial thermoplasty in the PAS2 study. We compared the first 190 PAS2 subjects with the 190 bronchial thermoplasty-treated subjects in the AIR2 trial at 3 years of follow-up. The PAS2 subjects were older (mean age 45.9 versus 40.7 years) and more obese (mean body mass index 32.5 versus 29.3 kg·m−2) and took higher doses of inhaled corticosteroids (mean dose 2301 versus 1961 μg·day−1). More PAS2 subjects had experienced severe exacerbations (74% versus 52%) and hospitalisations (15.3% versus 4.2%) in the 12 months prior to bronchial thermoplasty. At year 3 after bronchial thermoplasty, the percentage of PAS2 subjects with severe exacerbations, emergency department visits and hospitalisations significantly decreased by 45%, 55% and 40%, respectively, echoing the AIR2 results. The PAS2 study demonstrates similar improvements in asthma control after bronchial thermoplasty compared with the AIR2 trial despite enrolling subjects who may have had poorer asthma control. PMID:28860266

  2. Composite materials for aircraft structures

    National Research Council Canada - National Science Library

    Baker, A. A; Dutton, Stuart; Kelly, Donald

    2004-01-01

    ... materials for aircraft structures / Alan Baker, Stuart Dutton, and Donald Kelly- 2nd ed. p. cm. - (Education series) Rev. ed. of: Composite materials for aircraft structures / edited by B. C. Hos...

  3. MODELLING OF SOME AIRCRAFT PARAMETERS

    African Journals Online (AJOL)

    . There has, therefore, been a wide range reaction against aircraft noise in particular by community residents living close to the airports. Research has, thus, been mainly on effect of aircraft noise particularly and environmental noise and ...

  4. Variability of annoyance response due to aircraft noise

    Science.gov (United States)

    Dempsey, T. K.; Cawthorn, J. M.

    1979-01-01

    An investigation was conducted to study the variability in the response of subjects participating in noise experiments. This paper presents a description of a model developed to include this variability which incorporates an aircraft-noise adaptation level or an annoyance calibration for each individual. The results indicate that the use of an aircraft-noise adaption level improved prediction accuracy of annoyance responses (and simultaneously reduced response variation).

  5. Effect of Short-Term Fasting on Systemic Cytochrome P450-Mediated Drug Metabolism in Healthy Subjects: A Randomized, Controlled, Crossover Study Using a Cocktail Approach

    NARCIS (Netherlands)

    Lammers, Laureen A.; Achterbergh, Roos; van Schaik, Ron H. N.; Romijn, Johannes A.; Mathôt, Ron A. A.

    2017-01-01

    Short-term fasting can alter drug exposure but it is unknown whether this is an effect of altered oral bioavailability and/or systemic clearance. Therefore, the aim of our study was to assess the effect of short-term fasting on oral bioavailability and systemic clearance of different drugs. In a

  6. Effect of Short-Term Fasting on Systemic Cytochrome P450-Mediated Drug Metabolism in Healthy Subjects: A Randomized, Controlled, Crossover Study Using a Cocktail Approach

    NARCIS (Netherlands)

    L.A. Lammers (Laureen); Achterbergh, R. (Roos); R.H.N. van Schaik (Ron); J.A. Romijn (Johannes); R.A. Mathot (Ron)

    2017-01-01

    textabstractBackground and Objective: Short-term fasting can alter drug exposure but it is unknown whether this is an effect of altered oral bioavailability and/or systemic clearance. Therefore, the aim of our study was to assess the effect of short-term fasting on oral bioavailability and systemic

  7. Social participation and subjective well-being of long-term unemployed : why is paid work so hard to substitute for?

    NARCIS (Netherlands)

    van Bruggen, AC; Diener, E; Rahtz, DR

    2000-01-01

    In a study of SWB among 948 Dutch long-term unemployed, the two main questions were (I) do long-term unemployed learn To adjust, i.e. does the negative effect on SWB wear off over unemployment duration?; and (2) does social participation help adjustment and restoration of SWB? The effect of

  8. Aircraft Landing and Attitude Control Using Dynamic Matrix Control

    Directory of Open Access Journals (Sweden)

    George Cristian Calugaru

    2017-06-01

    Full Text Available This paper proposes a method for an efficient control of the aircraft landing and attitude through Dynamic Matrix Control. The idea of MPC structures used in aircraft control has been well established during the last few years, but some aspects require further investigation. With this in mind, the paper proposes structures for aircraft landing and aircraft attitude control by using single DMC controllers for landing and respectively one DMC controller for each of the attitude axis (pitch attitude hold, bank angle hold and heading hold. The model used for analysis of the aircraft landing structure is based on the last phase of landing. Also, the model used to illustrate the attitude control is that of a pitch attitude hold system of a N250-100 aircraft. Simulations are performed for a variety of control and prediction horizons, taking into account the possibility of adding a weighting factor for the control actions. Apart from separate studies on step reference variations, for some use cases, a generic reference trajectory is provided as a control purpose of the system. Results show a better performance of the proposed method in terms of control surface transition and protection of the actuators involved and a better time response in stabilizing the aircraft attitude. Overall, the aspects shown ensure an improved aircraft attitude control and landing stabilization.

  9. 26 CFR 31.3121(f)-1 - American vessel and aircraft.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 15 2010-04-01 2010-04-01 false American vessel and aircraft. 31.3121(f)-1... § 31.3121(f)-1 American vessel and aircraft. (a) The term “American vessel” means any vessel which is...”, see § 31.3121 (e)-1.) (b) The term “American aircraft” means any aircraft registered under the laws of...

  10. Effects of short-term caloric restriction on circulating free IGF-I, acid-labile subunit, IGF-binding proteins (IGFBPs)-1-4, and IGFBPs-1-3 protease activity in obese subjects

    DEFF Research Database (Denmark)

    Rasmussen, Michael Højby; Juul, Anders; Kjems, Lise Lund

    2006-01-01

    Decreased levels of GH and total IGF-I have been reported in obesity. It has been hypothesized that increased free (biologically active) IGF-I levels generated from IGF-binding protein (IGFBP) protease activity could be the mechanism for the low GH release in dieting obese subjects. However, no p...... a short-term very low-calorie diet (VLCD)....

  11. A short-term evaluation of the relationship between plasma ascorbic acid levels and periodontal disease in systemically healthy and type 2 diabetes mellitus subjects.

    Science.gov (United States)

    Gokhale, Neeraja H; Acharya, Anirudh B; Patil, Vidya S; Trivedi, Dheeraj J; Thakur, Srinath L

    2013-06-01

    Deficient ascorbic acid levels (AALs) and Type 2 diabetes mellitus (T2DM) are associated with periodontal disease. This study evaluated the relationship between plasma AAL and periodontitis in systemically healthy and T2DM subjects, which to the best of our knowledge is being reported for the first time. One hundred twenty subjects were categorized into four groups of 30 each as group 1: without periodontal disease; group 2: chronic gingivitis; group 3: chronic periodontitis, and group 4: chronic periodontitis and freshly diagnosed T2DM. Plaque index (PlI), sulcus bleeding index (SBI), and probing pocket depths (PPDs) were evaluated. Venous blood was evaluated for plasma AAL spectrophotometrically. Randomized subjects were subgrouped within groups 2-4, to receive either scaling and root planing (SRP) with dietary supplementation (450 mg) of ascorbic acid (AA) for two weeks or only SRP. After two weeks, the clinical parameters were reassessed. Tukey's multiple post hoc procedures and paired t test were used with the level of statistical significance adjusted to p ≤ .05. AAL plasma levels were significantly greater in group 1 than in group 2 (p = .0007) and in group 4 (p = .0003). A significant reduction in the SBI was seen in the subgroups that received dietary supplementation of vitamin C within group 2 (p = .0012) and group 4 (p = .036). Plasma AAL is below the normal range in systemically healthy subjects with gingivitis and diabetics with periodontitis. Dietary AA supplementation with SRP improves the SBI in subjects with gingivitis and diabetics with periodontitis.

  12. Annoyance and acceptability judgements of noise produced by three types of aircraft by residents living near JFK Airport

    Science.gov (United States)

    Borsky, P. N.

    1974-01-01

    A random sample of selected communities near JFK Airport were interviewed. Subsamples, with differing feelings of fear of aircraft crashes and different locations of residence were invited to participate in a laboratory experiment. The subjects were exposed to tape recordings of simulated flyovers of aircraft in approach and departure operations at nominal distances from the airport. The subjects judged the extent of noise annoyance and acceptability of the aircraft noises. Results indicate that level of noise is most significant in affecting annoyance judgements. Subjects with feelings of high fear report significantly more annoyance and less acceptability of aircraft noise than subjects with feelings of low fear.

  13. The Aircraft Industry, 2006

    Science.gov (United States)

    2006-01-01

    France Eurocopter , Marseille, France Organization of Economic Cooperation and Development, Paris, France Rolls Royce Aircraft Engines, Civil and...A320/340/380 Production Lines, Blagnac, France BAE Systems plc Corporate Offices, London, United Kingdom Dassault Corporate Headquarters, St. Cloud...Defence Aerospace Divisions, Derby, United Kingdom Societe Nationale d’Etude et de Construction de Moteurs d’Aviation (SNECMA), Evry, France

  14. Robots for Aircraft Maintenance

    Science.gov (United States)

    1993-01-01

    Marshall Space Flight Center charged USBI (now Pratt & Whitney) with the task of developing an advanced stripping system based on hydroblasting to strip paint and thermal protection material from Space Shuttle solid rocket boosters. A robot, mounted on a transportable platform, controls the waterjet angle, water pressure and flow rate. This technology, now known as ARMS, has found commercial applications in the removal of coatings from jet engine components. The system is significantly faster than manual procedures and uses only minimal labor. Because the amount of "substrate" lost is minimal, the life of the component is extended. The need for toxic chemicals is reduced, as is waste disposal and human protection equipment. Users of the ARMS work cell include Delta Air Lines and the Air Force, which later contracted with USBI for development of a Large Aircraft Paint Stripping system (LARPS). LARPS' advantages are similar to ARMS, and it has enormous potential in military and civil aircraft maintenance. The technology may also be adapted to aircraft painting, aircraft inspection techniques and paint stripping of large objects like ships and railcars.

  15. Aircraft to Medicine

    Science.gov (United States)

    1991-01-01

    This video discusses how the technology of computer modeling can improve the design and durability of artificial joints for human joint replacement surgery. Also, ultrasound, originally used to detect structural flaws in aircraft, can also be used to quickly assess the severity of a burn patient's injuries, thus aiding the healing process.

  16. Is aircraft noise exposure associated with cardiovascular disease and hypertension? Results from a cohort study in Athens, Greece.

    Science.gov (United States)

    Dimakopoulou, Konstantina; Koutentakis, Konstantinos; Papageorgiou, Ifigeneia; Kasdagli, Maria-Iosifina; Haralabidis, Alexandros S; Sourtzi, Panayota; Samoli, Evangelia; Houthuijs, Danny; Swart, Wim; Hansell, Anna L; Katsouyanni, Klea

    2017-11-01

    We followed up, in 2013, the subjects who lived near the Athens International Airport and had participated in the cross-sectional multicountry HYENA study in 2004-2006. To evaluate the association of exposure to aircraft and road traffic noise with the incidence of hypertension and other cardiovascular outcomes. From the 780 individuals who participated in the cross-sectional study, 537 were still living in the same area and 420 accepted to participate in the follow-up. Aircraft and road traffic noise exposure was based on the estimations conducted in 2004-2006, linking geocoded residential addresses of the participants to noise levels. We applied multiple logistic regression and Cox proportional hazards models, adjusting for potential confounders. The incidence of hypertension was significantly associated with higher aircraft noise exposure during the night. Specifically, the OR for hypertension per 10 dB increase in Lnight aircraft noise exposure was 2.63 (95% CI 1.21 to 5.71). Doctor-diagnosed cardiac arrhythmia was significantly associated with Lnight aircraft noise exposure, when prevalent and incident cases were considered with an OR of 2.09 (95% CI 1.07 to 4.08). Stroke risk was also increased with increasing noise exposure but the association was not significant. Twenty-four-hour road traffic noise associations with the outcomes considered were weaker and less consistent. In conclusion, our cohort study suggests that long-term exposure to aircraft noise, particularly during the night, is associated with incident hypertension and possibly, also, cardiovascular effects. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  17. Minor long-term changes in weight have beneficial effects on insulin sensitivity and beta-cell function in obese subjects

    DEFF Research Database (Denmark)

    Rosenfalck, A M; Hendel, Helle Westergren; Rasmussen, M H

    2002-01-01

    To evaluate the long-term effect of changes in body composition induced by weight loss on insulin sensitivity (SI), non-insulin mediated glucose disposal, glucose effectiveness (SG)and beta-cell function.......To evaluate the long-term effect of changes in body composition induced by weight loss on insulin sensitivity (SI), non-insulin mediated glucose disposal, glucose effectiveness (SG)and beta-cell function....

  18. Lightweight sidewalls for aircraft interior noise control

    Science.gov (United States)

    May, D. N.; Plotkin, K. J.; Selden, R. G.; Sharp, B. H.

    1985-01-01

    A theoretical and experimental study was performed to devise lightweight sidewalls for turboprop aircraft. Seven concepts for new sidewalls were analyzed and tested for noise reduction using flat panels of 1.2 m x 1.8 m (4 ft x 6 ft), some of which were aircraft-type constructions and some of which were simpler, easier-to-construct panels to test the functioning of an acoustic principle. Aircraft-application sidewalls were then conceived for each of the seven concepts, and were subjectively evaluated for their ability to meet aircraft nonacoustic design requirements. As a result of the above, the following sidewall concepts were recommended for further investigation: a sidewall in which the interior cavity is vented to ceiling and underfloor areas; sidewalls with wall-mounted resonators, one having a conventional trim panel and one a limp one; and a sidewall with a stiff outer wall and a limp trim panel. These sidewalls appear to promise lower weights than conventional sidewalls adjusted to meet similar acoustic requirements, and further development may prove them to be practical.

  19. Raptor responses to low-level jet aircraft and sonic booms

    Science.gov (United States)

    Ellis, David H.; Ellis, Catherine H.; Mindell, David P.

    1991-01-01

    We estimated effects of low-level military jet aircraft and mid- to high-altitude sonic booms (actual and simulated) on nesting peregrine falcons (Falco peregrinus) and seven other raptors by observing their responses to test stimuli, determining nesting success for the test year, and evaluating site reoccupancy rates for the year following the tests. Frequent and nearby jet aircraft passes: (1) sometimes noticeably alarmed birds, (2) occasionally caused birds to fly from perches or eyries, (3) most often evoked only minimal responses, and (4) were never associated with reproductive failure. Similarly, responses to real and simulated mid- to high-altitude sonic booms were often minimal and never appeared productivity limiting. Eighteen (95%) of 19 nest sites subjected to low-level jet flights and/or simulated sonic booms in 1980 fledged young during that year. Eighteen (95%) of 19 sites disturbed in 1980 were reoccupied by pairs or lone birds of the same species in 1981.We subjected four pairs of prairie falcons (Falco mexicanus) to low-level aircraft at ad libitum levels during the courtship and incubation phases when adults were most likely to abandon: all four eyries fledged young. From heart rate (HR) data taken via a telemetering egg at another prairie falcon eyrie, we determined that stimulus-induced HR alterations were comparable to rate changes for birds settling to incubate following flight.While encouraging, our findings cannot be taken as conclusive evidence that jet flights and/or sonic booms will have no long-term negative effects for other raptor species or for other areas. In addition, we did not experiment with totally naive wild adults, rotary-winged aircraft, or low-level sonic booms.

  20. [Slowing down the rate of irreversible age-related atrophy of the thymus gland by atopic autotransplantation of its tissue, subjected to long-term cryoconservation].

    Science.gov (United States)

    Kulikov, A V; Arkhipova, L V; Smirnova, G N; Novoselova, E G; Shpurova, N A; Shishova, N V; Sukhikh, G T

    2010-01-01

    An experimental procedure has been developed enabling to slow down the rate of irreversible atrophy of the thymus gland. The atopic autotransplantation of its tissue subjected to prolonged cryoconservation enables one to inhibit the aging of the organism with respect to several biochemical and immunological indicators.

  1. The Examination of Secondary Education Chemistry Curricula Published between 1957-2007 in Terms of the Dimensions of Rationale, Goals, and Subject-Matter

    Science.gov (United States)

    Pekdag, Bulent; Erol, Hilal

    2013-01-01

    Fifteen secondary education chemistry curricula published from 1957 until 2007 were examined based on the dimensions of rationale, goals, and subject matter. An examination of documents in the scope of qualitative research was carried out in the study. The goals included in the examined chemistry curricula were analyzed according to the cognitive,…

  2. Response of geese to aircraft disturbances

    Science.gov (United States)

    Ward, David; Stehn, Robert A.; Derksen, Dirk V.

    2000-01-01

    Low-flying aircraft can affect behavior, physiology, and distribution of wildlife (Manci et al., 1988), and over time, may impact a population by reducing survival and reproductive performance. Thus, it is important to identify the particular aspects of overflights that affect animals so that management strategies can be developed to minimize adverse effects.Waterfowl are particularly sensitive to low-flying aircraft (Manci et al., 1988) and respond at all stages of their annual cycle, including breeding (Gollop et al., 1974a; Laing, 1991), molting (Derksen et al., 1979; Mosbech and Glahder, 1991), migration (Jones and Jones, 1966; Belanger and Bedard, 1989), and wintering (Owens, 1977; Kramer et al., 1979; Henry, 1980). Waterfowl response can be quite variable both within and among species (Fleming et al., 1996). For example, response can vary with age, sex, and body condition of individual, habitat type and quality, and previous exposure to aircraft (Dahlgren and Korshgen, 1992). However, the most important factors influencing a response are aircraft type (Davis and Wiseley, 1974; Jensen, 1990), noise (Mosbech and Glahder, 1991; Temple, 1993), and proximity to the birds, as measured in altitude and lateral distance (Derksen et al., 1979; Belanger and Bedard, 1989; Ward et al., 1994). Wildlife managers can reduce impacts on a population by controlling or modifying these factors.In an experimental study conducted at Izembek Lagoon in southwestern Alaska in 1985-1988 (Ward and Stehn, 1989), we conducted planned aircraft overflights with control of aircraft type, noise, altitude, and lateral distance to flocks (hereafter called lateral distance) to measure behavioral response of fall-staging Pacific brant (Branta bernicla nigricans) and Canada geese (B. canadensis taverneri) to fixed- and rotary-wing aircraft. These data were then used to develop predictive models of the relationship between aircraft type, noise, altitude, and lateral distance and the response of

  3. Weed detection using unmanned aircraft vehicles

    Directory of Open Access Journals (Sweden)

    Pflanz, Michael

    2014-03-01

    Full Text Available In contrast to agricultural remote sensing technologies, which are based on images from satellites or manned aircrafts, photogrammetry at low altitude from unmanned aircraft vehicles lead to higher spatial resolution, real-time processing and lower costs. Moreover multicopter aircrafts are suitable vehicles to perform precise path or stationary flights. In terms of vegetation photogrammetry this minimises motion blur and provide better image overlapping for stitching and mapping procedures. Through improved image analyses and through the recent increase in the availability of powerful batteries, microcontrollers and multispectral cameras, it can be expected in future that spatial mapping of weeds from low altitudes will be promoted. A small unmanned aircraft vehicle with a modified RGB camera was tested taking images from agricultural fields. A microcopter with six rotors was applied. The hexacopter in particular is GPS controlled and operates within predefined areas at given altitudes (from 5 to 10 m. Different scenarios of photogrammetrically weed detection have been carried out regarding to variable altitude, image resolution, weed and crop growth stages. First experiences with microcopter showed a high potential for site-specific weed control. Images analyses with regards to recognition of weed patches can be used to adapt herbicide applications to varying weed occurrence across a field.

  4. Training-induced changes in muscle CSA, muscle strength, EMG, and rate of force development in elderly subjects after long-term unilateral disuse

    DEFF Research Database (Denmark)

    Suetta, Charlotte; Aagaard, Per; Rosted, Anna

    2004-01-01

    The ability to develop muscle force rapidly may be a very important factor to prevent a fall and to perform other tasks of daily life. However, information is still lacking on the range of training-induced neuromuscular adaptations in elderly humans recovering from a period of disuse. Therefore......, the present study examined the effect of three types of training regimes after unilateral prolonged disuse and subsequent hip-replacement surgery on maximal muscle strength, rapid muscle force [rate of force development (RFD)], muscle activation, and muscle size. Thirty-six subjects (60-86 yr) were randomized...... to a 12-wk rehabilitation program consisting of either 1) strength training (3 times/wk for 12 wk), 2) electrical muscle stimulation (1 h/day for 12 wk), or 3) standard rehabilitation (1 h/day for 12 wk). The nonoperated side did not receive any intervention and thereby served as a within-subject control...

  5. Short-term corneal changes with gas-permeable contact lens wear in keratoconus subjects: a comparison of two fitting approaches.

    Science.gov (United States)

    Romero-Jiménez, Miguel; Santodomingo-Rubido, Jacinto; Flores-Rodríguez, Patricia; González-Méijome, Jose-Manuel

    2015-01-01

    To evaluate changes in anterior corneal topography and higher-order aberrations (HOA) after 14-days of rigid gas-permeable (RGP) contact lens (CL) wear in keratoconus subjects comparing two different fitting approaches. Thirty-one keratoconus subjects (50 eyes) without previous history of CL wear were recruited for the study. Subjects were randomly fitted to either an apical-touch or three-point-touch fitting approach. The lens' back optic zone radius (BOZR) was 0.4mm and 0.1mm flatter than the first definite apical clearance lens, respectively. Differences between the baseline and post-CL wear for steepest, flattest and average corneal power (ACP) readings, central corneal astigmatism (CCA), maximum tangential curvature (KTag), anterior corneal surface asphericity, anterior corneal surface HOA and thinnest corneal thickness measured with Pentacam were compared. A statistically significant flattening was found over time on the flattest and steepest simulated keratometry and ACP in apical-touch group (all pcontact lens wear (all plens wear. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  6. Price-Weight Relationships of General Aviation, Helicopters, Transport Aircraft and Engines

    Science.gov (United States)

    Anderson, Joseph L.

    1981-01-01

    The NASA must assess its aeronautical research program with economic as well as performance measures. It thus is interested in what price a new technology aircraft would carry to make it attractive to the buyer. But what price a given airplane or helicopter will carry is largely a reflection of the manufacturer's assessment of the competitive market into which the new aircraft will be introduced. The manufacturer must weigh any new aerodynamic or system technology innovation he would add to an aircraft by the impact of this innovation upon the aircraft's cost to manufacture, economic attractiveness and price. The intent of this paper is to give price standards against which new technologies and the NASA's research program can be assessed. Using reported prices for sailplanes, general aviation, agriculture, helicopter, business and transport aircraft, price estimating relations in terms of engine and airframe characteristics have been developed. The relations are given in terms of the aircraft type, its manufactured empty weight, engine weight, horsepower or thrust. Factors for the effects of inflation are included to aid in making predictions of future aircraft prices. There are discussions of aircraft price in terms of number of passenger seats, airplane size and research and development costs related to an aircraft model, and indirectly how new technologies, aircraft complexity and inflation have affected these.

  7. Aircraft specific exhaust emissions

    Energy Technology Data Exchange (ETDEWEB)

    Lecht, M.; Deidewig, F.; Doepelheuer, A. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Koeln (Germany). Inst. fuer Antriebstechnik

    1997-12-01

    The objective of this work to calculate essential species of aircraft emissions has been approached by a combination of different tasks. First of all engine performance and emission correlation has been modelled taking sea level static measurements from the engine certification process as a reference. At second a flight simulation program has been modified to couple aircraft and engine performance along a flight mission profile. By this for a selected number of aircraft/engine combinations the emissions of NO{sub x}, CO and HC as well as fuel burn for short, medium and long haul flights have been calculated and finally adapted to a specified format of flight distance and altitude increments. Sensitivity studies of the change of emissions along the cruise section showed a 30% decrease of the NO{sub x} emission rate until the end of cruise. Differences of ambient air temperature from ISA conditions will have a substantial impact on NO{sub x}, CO and HC emissions rather than on mission fuel. (orig.) 144 figs., 42 tabs., 497 refs.

  8. Subjective safety in traffic.

    NARCIS (Netherlands)

    2012-01-01

    The termsubjective safety in traffic’ refers to people feeling unsafe in traffic or, more generally, to anxiety regarding being unsafe in traffic for oneself and/or others. Subjective safety in traffic can lead to road users limiting their mobility and social activities, which is one of the

  9. Subjective poverty line definitions

    NARCIS (Netherlands)

    J. Flik; B.M.S. van Praag (Bernard)

    1991-01-01

    textabstractIn this paper we will deal with definitions of subjective poverty lines. To measure a poverty threshold value in terms of household income, which separates the poor from the non-poor, we take into account the opinions of all people in society. Three subjective methods will be discussed

  10. Advanced turboprop aircraft flyover noise annoyance

    Science.gov (United States)

    Mccurdy, David A.

    1989-01-01

    Results from recent laboratory experiments in which human subjects were exposed to synthetic sounds simulating the flyover noise emitted by advanced turbofan aircraft engines are briefly summarized. The Aircraft Noise Synthesis System described by McCurdy et al. (1987) is used to simulate the noise from (1) a conventional turboprop engine, (2) a jet engine, (3) a single-rotating turbofan engine, and counterrotating turbofans with (4) equal or (5) unequal numbers of blades on the two rotors. The measured annoyance levels are compared with effective perceived noise levels in a graph. For a given noise level, the annoyance levels for (3) are shown to be slightly lower than those for all the other engine types, especially if the tone/broadband noise ratio is relatively high.

  11. Long term effectiveness of once-daily unboosted atazanavir plus abacavir/lamivudine as a switch strategy in subjects with virological suppression

    DEFF Research Database (Denmark)

    Llibre, Josep M; Cozzi-Lepri, Alessandro; La Rosa, Jorge Antonio Valencia

    2014-01-01

    routine however are scant. METHODS: We evaluated treatment outcomes of ATV400+ABC/3TC in pre-treated subjects in the EuroSIDA cohort with undetectable HIV-1 RNA, and previous ABC experience or assumed previous HLA B57*01 testing. We performed a time to loss of virologic response (TLOVR below 50 c....../mL) and a snapshot analysis at 48, 96 and 144 weeks. Virological failure (VF) was defined as a confirmed plasma HIV-1 RNA >50 c/mL. RESULTS: We included 258 subjects: 176 (68%) male, median age 46 (IQR 41, 53) y, 225 (87.2%) white, hepatitis virus co-infection 36%, median baseline CD4 at switch 540 cells (360, 700......, respectively, 89.5 [95% CI 85.1, 92.9]/88 [83.4, 91.7]/86.3% [81.6, 90.4] (TLOVR, composite endpoint failure or stop for any reason) and the risk of VF was 8.3/7.6/7.6%. In the snapshot analysis HIV-RNA was below 50 c/mL in 72.5/65.9/51.6%, respectively, and >50 c/mL in 6.6/5.4/4.3%. Only 0...

  12. Short-Term Exercise Training Improves Insulin Sensitivity but Does Not Inhibit Inflammatory Pathways in Immune Cells from Insulin-Resistant Subjects

    Directory of Open Access Journals (Sweden)

    Sara M. Reyna

    2013-01-01

    Full Text Available Background. Exercise has an anti-inflammatory effect against, and immune cells play critical roles in the development, of insulin resistance and atherosclerotic vascular disease (AVD. Thus, the goal of this study was to determine whether exercise improves insulin sensitivity in insulin-resistant subjects by downregulating proinflammatory signaling in immune cells. Methods. Seventeen lean, 8 obese nondiabetic, and 11 obese type 2 diabetic individuals underwent an aerobic exercise program for 15 days and an insulin clamp before and after exercise. Peripheral mononuclear cells (PMNC were obtained for determination of Toll-like receptor (TLR 2 and 4 protein content and mitogen-activated protein kinase phosphorylation. Results. Compared with that in lean individuals, TLR4 protein content was increased by 4.2-fold in diabetic subjects. This increase in TLR4 content was accompanied by a 3.0-fold increase in extracellular signal-regulated kinase (ERK phosphorylation. Exercise improved insulin sensitivity in the lean, obese, and type 2 diabetes groups. However, exercise did not affect TLR content or ERK phosphorylation. Conclusions. TLR4 content and ERK phosphorylation are increased in PMNC of type 2 diabetic individuals. While exercise improves insulin sensitivity, this effect is not related to changes in TLR2/TLR4 content or ERK phosphorylation in PMNC of type 2 diabetic individuals.

  13. Ablative fractional CO2laser for burn scar reconstruction: An extensive subjective and objective short-term outcome analysis of a prospective treatment cohort.

    Science.gov (United States)

    Issler-Fisher, Andrea C; Fisher, Oliver M; Smialkowski, Ania O; Li, Frank; van Schalkwyk, Constant P; Haertsch, Peter; Maitz, Peter K M

    2017-05-01

    The introduction of ablative fractional CO 2 lasers (CO 2 -AFL) for burn scar management shows promising results. Whilst recent studies have focused on objective scar outcomes following CO 2 -AFL treatment, to date no data on patient subjective factors such as quality of life are available. A prospective study was initiated to analyze the safety and efficacy of the CO 2 -AFL. Various objective and subjective outcome parameters were prospectively collected from the date of first consultation and follow-up following treatment. Objective factors include the Vancouver Scar Scale (VSS), the Patient and Observer Scar Assessment Scale (POSAS), and ultrasound measurements of the thickness of the scar. Subjective parameters included the assessment of neuropathic pain and pruritus, as well as the evaluation of improvement of quality of life following CO 2 -AFL with the Burns Specific Health Scale (BSHS-B). For treatment effect analysis, patients were stratified according to scar maturation status (> or <2 years after injury). 47 patients with 118 burn scars completed at least one treatment cycle. At a median of 55 days (IQR 32-74) after CO 2 -AFL treatment all analyzed objective parameters decreased significantly: intra-patient normalized scar thickness decreased from a median of 2.4mm to 1.9mm (p<0.001) with a concomitant VSS-drop from a median of 7 to 6 (p<0.001). The overall POSAS patient scale decreased from a median of 9 to 5 (p<0.001) with similar effects documented in POSAS observer scales. Both pain and pruritus showed significant reduction. Quality of life increased significantly by 15 points (median 120 to 135; p<0.001). All of the identified changes following CO 2 -AFL were equally significant irrespective of scar maturation status. Our preliminary results confirm significant improvement in thickness, texture, colour, and symptoms following treatment with CO 2 -AFL. Foremost, quality of life of patients with both immature and mature scars (up to 23 years after

  14. Increased hippocampal, thalamus and amygdala volume in long-term lithium-treated bipolar I disorder patients compared with unmedicated patients and healthy subjects.

    Science.gov (United States)

    López-Jaramillo, Carlos; Vargas, Cristian; Díaz-Zuluaga, Ana M; Palacio, Juan David; Castrillón, Gabriel; Bearden, Carrie; Vieta, Eduard

    2017-02-01

    Magnetic resonance imaging (MRI) studies in bipolar I disorder (BD-I) suggest that lithium is associated with increased volumes of cortico-limbic structures. However, more rigorous control of confounding factors is needed to obtain further support for this hypothesis. The aim of the present study was to assess differences in brain volumes among long-term lithium-treated BD-I patients, unmedicated BD-I patients, and healthy controls. This was a cross-sectional study with 32 euthymic BD-I patients (16 on lithium monotherapy for a mean of 180 months, and 16 receiving no medication for at least the 2 months prior to the study) and 20 healthy controls. Patients were euthymic (Hamilton Depression Rating Scale [HDRS] lithium for at least 6 months. Brain images were acquired on a 1.5 Tesla MRI (Phillips, Amsterdam, The Netherlands) and segmented to generate volumetric measures of cortical and subcortical brain areas, ventricles and global brain. Significant differences were found in the volumes of the left amygdala (P=.0003), right amygdala (P=.030), left hippocampus (P=.022), left thalamus (P=.022), and right thalamus (P=.019) in long-term lithium-treated BD-I patients, compared to unmedicated patients and controls, after multivariable adjustment. No differences were observed in global brain volume or in ventricular size among the three groups. Likewise, there was no correlation between serum lithium levels and the increase in size in the described brain areas. The structural differences found among the three groups, and specifically those between long-term lithium-treated and unmedicated BD-I patients, indicate increased limbic structure volumes in lithium-treated patients. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Short term non-invasive ventilation post-surgery improves arterial blood-gases in obese subjects compared to supplemental oxygen delivery - a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Zoremba Norbert

    2011-05-01

    Full Text Available Abstract Background In the immediate postoperative period, obese patients are more likely to exhibit hypoxaemia due to atelectasis and impaired respiratory mechanics, changes which can be attenuated by non-invasive ventilation (NIV. The aim of the study was to evaluate the duration of any effects of early initiation of short term pressure support NIV vs. traditional oxygen delivery via venturi mask in obese patients during their stay in the PACU. Methods After ethics committee approval and informed consent, we prospectively studied 60 obese patients (BMI 30-45 undergoing minor peripheral surgery. Half were randomly assigned to receive short term NIV during their PACU stay, while the others received routine treatment (supplemental oxygen via venturi mask. Premedication, general anaesthesia and respiratory settings were standardized. We measured arterial oxygen saturation by pulse oximetry and blood gas analysis on air breathing. Inspiratory and expiratory lung function was measured preoperatively (baseline and at 10 min, 1 h, 2 h, 6 h and 24 h after extubation, with the patient supine, in a 30 degrees head-up position. The two groups were compared using repeated-measure analysis of variance (ANOVA and t-test analysis. Statistical significance was considered to be P Results There were no differences at the first assessment. During the PACU stay, pulmonary function in the NIV group was significantly better than in the controls (p Conclusion Early initiation of short term NIV during in the PACU promotes more rapid recovery of postoperative lung function and oxygenation in the obese. The effect lasted 24 hours after discontinuation of NIV. Patient selection is necessary in order to establish clinically relevant improvements. Trial Registration# DRKS00000751; http://www.germanctr.de

  16. Nutri-metabolomics: subtle serum metabolic differences in healthy subjects by NMR-based metabolomics after a short-term nutritional intervention with two tomato sauces.

    Science.gov (United States)

    Bondia-Pons, Isabel; Cañellas, Nicolau; Abete, Itziar; Rodríguez, Miguel Ángel; Perez-Cornago, Aurora; Navas-Carretero, Santiago; Zulet, M Ángeles; Correig, Xavier; Martínez, J Alfredo

    2013-12-01

    Postgenomics research and development is witnessing novel intersections of omics data intensive technology and applications in health and personalized nutrition. Chief among these is the nascent field of nutri-metabolomics that harnesses metabolomics platforms to discern person-to-person variations in nutritional responses. To this end, differences in the origin and ripening stage of fruits might have a strong impact on their phytochemical composition, and consequently, on their potential nutri-metabolomics effects on health. The objective of the present study was to evaluate the effects of a 4-week cross-over nutritional intervention on the metabolic status of 24 young healthy subjects. The intervention was carried out with two tomato sauces differing in their natural lycopene content, which was achieved by using tomatoes harvested at different times. Blood samples were drawn from each subject before and after each intervention period. Aqueous and lipid extracts from serum samples were analyzed by 1H-NMR metabolic profiling combined with analysis of variance simultaneous component analysis (ASCA) and multilevel simultaneous component analysis (MSCA). These methods allowed the interpretation of the variation induced by the main factors of the study design (sauce treatment and time). The levels of creatine, creatinine, leucine, choline, methionine, and acetate in aqueous extracts were increased after the intervention with the high-lycopene content sauce, while those of ascorbic acid, lactate, pyruvate, isoleucine, alanine were increased after the normal-lycopene content sauce. In conclusion, NMR-based metabolomics of aqueous and lipid extracts allowed the detection of different metabolic changes after the nutritional intervention. This outcome might partly be due to the different ripening state of the fruits used in production of the tomato sauces. The findings presented herein collectively attest to the emergence of the field of nutri-metabolomics as a novel

  17. 19 CFR 122.64 - Other aircraft.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Other aircraft. 122.64 Section 122.64 Customs... AIR COMMERCE REGULATIONS Clearance of Aircraft and Permission To Depart § 122.64 Other aircraft. Clearance or permission to depart shall be requested by the aircraft commander or agent for aircraft covered...

  18. Variability in the intraspecific response of Pinus ponderosa seedlings subjected to long-term exposure to elevated CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Houpis, J.L.J.; Anschel, D.J. [Lawrence Livermore National Lab., CA (United States). Health and Ecological Assessment Div.; Pushnik, J.C. [California State Univ., Chico, CA (United States). Dept. of Biological Sciences; Anderson, P.D. [Forest Service, Rhinelander, WI (United States)

    1995-01-01

    The authors are investigating the effects of elevated CO{sub 2} and intraspecific variability on Pinus ponderosa. To analyze intraspecific variability, they included seedling source (family) as an additional treatment, using a split-plot experimental design. The three elevated CO{sub 2} treatments were ambient (approx. 350 ppm CO{sub 2}), ambient + 175 ppm CO{sub 2} and ambient +350 ppm CO{sub 2}. Their study uses the source/sink control framework at several key integrating steps, incorporating the long-term effects of elevated CO{sub 2} (insuring sufficient time for the expression of any long-term physiological and biochemical acclimation to occur) and genetics (using multiple species and multiple known genetic sources) in an attempt to ascertain the extent of overall regulation contributed by selected independent regulatory process at the physiological, biochemical and structural level. In order to assess intraspecific variability, this paper reports on the integration of measurements of photosynthesis, chlorophyll fluorescence, pigmentation, RuBPCase, SPSase to quantify the effects of elevated CO{sub 2} on the growth response of various families of the same species.

  19. Analysis of Automated Aircraft Conflict Resolution and Weather Avoidance

    Science.gov (United States)

    Love, John F.; Chan, William N.; Lee, Chu Han

    2009-01-01

    This paper describes an analysis of using trajectory-based automation to resolve both aircraft and weather constraints for near-term air traffic management decision making. The auto resolution algorithm developed and tested at NASA-Ames to resolve aircraft to aircraft conflicts has been modified to mitigate convective weather constraints. Modifications include adding information about the size of a gap between weather constraints to the routing solution. Routes that traverse gaps that are smaller than a specific size are not used. An evaluation of the performance of the modified autoresolver to resolve both conflicts with aircraft and weather was performed. Integration with the Center-TRACON Traffic Management System was completed to evaluate the effect of weather routing on schedule delays.

  20. FEATURES OF SPREAD OF VORTEX WAKE BEHIND AIRCRAFT AT TAKEOFF AND LANDING, IF CROSSWINDS

    Directory of Open Access Journals (Sweden)

    A. I. Zhelannikov

    2016-01-01

    Full Text Available With cash-developed software system, were carried out research on the impact velocity crosswinds on the position of vortex wake at takeoff and landing of aircraft of various classes. Identify the threat, in terms of "hovering" of wing vortex over the center of the runway, crosswind speed. During takeoff and landing aircraft, these vortices can be a danger to other aircraft.

  1. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Manufacture of new aircraft, aircraft... Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b) and (c) of this section, no person may manufacture a new aircraft, aircraft engine, or propeller based on...

  2. Short-term efficacy of calcium fructoborate on subjects with knee discomfort: a comparative, double-blind, placebo-controlled clinical study

    Directory of Open Access Journals (Sweden)

    Pietrzkowski Z

    2014-06-01

    Full Text Available Zbigniew Pietrzkowski,1 Michael J Phelan,2 Robert Keller,3 Cynthia Shu,1 Ruby Argumedo,1 Tania Reyes-Izquierdo11FutureCeuticals, Inc., Applied BioClinical Laboratory; 2Department of Statistics, School of Information and Computer Science, University of California at Irvine; 3NutraClinical Inc., Irvine, CA, USAAbstract: Calcium fructoborate (CFB at a dose of 110 mg twice per day was previously reported to improve knee discomfort during the first 14 days of treatment. In this study, 60 participants with self-reported knee discomfort were randomized into two groups receiving CFB or placebo. Initial levels of knee discomfort were evaluated by Western Ontario and McMaster Universities Arthritis Index (WOMAC and McGill Pain Questionnaire (MPQ scores at the beginning of the study and also at 7 and 14 days after treatment. Results showed that supplementation with CFB significantly improved knee discomfort in the study subjects; significant reductions of mean within-subject change in WOMAC and MPQ scores were observed for the CFB group compared to the placebo group at both 7 and 14 days after treatment. Estimated treatment differences for the MPQ score were -5.8 (P=0.0009 and -8.9 (P<0.0001 at Day 7 and 14, respectively. Estimated differences for the WOMAC score were -5.3 (P=0.06 and -13.73 (P<0.0001 at Day 7 and 14, respectively. Negative values indicate greater reductions in reported discomfort. On both Day 7 and Day 14, the trend was toward greater improvement in the CFB group. The placebo group did not exhibit any change in the WOMAC and MPQ scores. In conclusion, supplementation with 110 mg CFB twice per day was associated with improving knee discomfort during the 2 weeks of intake.Keywords: CFB, joint discomfort, WOMAC score, McGill pain score

  3. Long-term follow-up of hepatic ultrasound findings in subjects with magnetic resonance imaging defined hepatic steatosis following clinical islet transplantation: a case-control study.

    Science.gov (United States)

    Jackson, Stephanie; Mager, Diana R; Bhargava, Ravi; Ackerman, Thomas; Imes, Sharleen; Hubert, Grace; Koh, Angela; Shapiro, A M James; Senior, Peter A

    2013-01-01

    Hepatic steatosis is one complication patients may experience following clinical islet transplantation (CIT), yet the cause and consequences of this are poorly understood. The purpose of this case-control study was to examine the relationship between hepatic steatosis, metabolic parameters and graft function in an Albertan cohort of CIT recipients. Hepatic steatosis was detected by magnetic resonance imaging (MRI) in n = 10 cases age-matched with n=10 MRI-negative controls. Progression/regression of steatosis was determined by ultrasound (US) in cases. Hepatic steatosis first appeared 2.8 ± 2.2 (mean ± SD) years post-CIT, and lasted approximately 4.6 ± 2.0 years. In five cases steatosis resolved, with recurrence in two cases during the follow-up period (8.5 ± 3.2 years). No evidence of CIT causing deleterious effects on long-term liver function or graft outcome was observed.

  4. Long-term follow-up of hepatic ultrasound findings in subjects with magnetic resonance imaging defined hepatic steatosis following clinical islet transplantation

    Science.gov (United States)

    Jackson, Stephanie; Mager, Diana R.; Bhargava, Ravi; Ackerman, Thomas; Imes, Sharleen; Hubert, Grace; Koh, Angela; Shapiro, A.M. James; Senior, Peter A.

    2013-01-01

    Hepatic steatosis is one complication patients may experience following clinical islet transplantation (CIT), yet the cause and consequences of this are poorly understood. The purpose of this case-control study was to examine the relationship between hepatic steatosis, metabolic parameters and graft function in an Albertan cohort of CIT recipients. Hepatic steatosis was detected by magnetic resonance imaging (MRI) in n = 10 cases age-matched with n=10 MRI-negative controls. Progression/regression of steatosis was determined by ultrasound (US) in cases. Hepatic steatosis first appeared 2.8 ± 2.2 (mean ± SD) years post-CIT, and lasted approximately 4.6 ± 2.0 years. In five cases steatosis resolved, with recurrence in two cases during the follow-up period (8.5 ± 3.2 years). No evidence of CIT causing deleterious effects on long-term liver function or graft outcome was observed. PMID:23514958

  5. Long-term use of oral nucleos(t)ide analogues for chronic hepatitis B does not increase cancer risk - a cohort study of 44 494 subjects.

    Science.gov (United States)

    Wong, G L-H; Tse, Y-K; Yip, T C-F; Chan, H L-Y; Tsoi, K K-F; Wong, V W-S

    2017-05-01

    Patients with chronic hepatitis B (CHB) need long-term antiviral treatment with nucleos(t)ide analogues (NA). Animal studies suggest that some NA may increase cancer risk, but human data are lacking. To investigate cancer risks in patients with or without NA treatment. We conducted a territory-wide cohort study using the database from Hospital Authority in Hong Kong. The diagnosis of CHB and various malignancies was based on the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis codes between 2000 and 2012. Patients exposed to any of the oral NA for CHB were included. The primary outcome was incident cancers. A 3-year landmark analysis, with follow-up up to 7 years, was used to evaluate the relative risk of cancers in treated and untreated patients. A total of 44 494 patients (39 712 untreated and 4782 treated) were included in the analysis. During 194 890 patient-years of follow-up, hepatocellular carcinoma developed in 402 (1.0%) untreated patients and 179 (3.7%) treated patients, while other cancers developed in 528 (1.3%) and 128 (2.7%) patients respectively. After propensity score weighting, treated patients had similar risks of all malignancies [weighted hazard ratio (wHR): 1.01, 95% CI: 0.82-1.25, P = 0.899], lung/pleural cancers (wHR: 0.82, 95% CI: 0.52-1.31, P = 0.409) and urinary/renal malignancies (wHR: 1.04, 95% CI: 0.38-2.81, P = 0.944) when compared with untreated patients. Oral nucleos(t)ide analogue treatment does not appear to increase cancer risk in patients with chronic hepatitis B. Given the beneficial effect on liver outcomes, our data support the current practice of long-term anti-viral therapy. © 2017 John Wiley & Sons Ltd.

  6. Expanding subjectivities

    DEFF Research Database (Denmark)

    Lundgaard Andersen, Linda; Soldz, Stephen

    2012-01-01

    A major theme in recent psychoanalytic thinking concerns the use of therapist subjectivity, especially “countertransference,” in understanding patients. This thinking converges with and expands developments in qualitative research regarding the use of researcher subjectivity as a tool to understa...

  7. Chemistry in aircraft plumes

    Energy Technology Data Exchange (ETDEWEB)

    Kraabol, A.G.; Stordal, F.; Knudsen, S. [Norwegian Inst. for Air Research, Kjeller (Norway); Konopka, P. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Wessling (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    An expanding plume model with chemistry has been used to study the chemical conversion of NO{sub x} to reservoir species in aircraft plumes. The heterogeneous conversion of N{sub 2}O{sub 5} to HNO{sub 3}(s) has been investigated when the emissions take place during night-time. The plume from an B747 has been simulated. During a ten-hour calculation the most important reservoir species was HNO{sub 3} for emissions at noon. The heterogeneous reactions had little impact on the chemical loss of NO{sub x} to reservoir species for emissions at night. (author) 4 refs.

  8. Commercial Aircraft Protection

    Energy Technology Data Exchange (ETDEWEB)

    Ehst, David A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-10-26

    This report summarizes the results of theoretical research performed during 3 years of P371 Project implementation. In results of such research a new scientific conceptual technology of quasi-passive individual infrared protection of heat-generating objects – Spatial Displacement of Thermal Image (SDTI technology) was developed. Theoretical substantiation and description of working processes of civil aircraft individual IR-protection system were conducted. The mathematical models and methodology were presented, there were obtained the analytical dependencies which allow performing theoretical research of the affect of intentionally arranged dynamic field of the artificial thermal interferences with variable contrast onto main parameters of optic-electronic tracking and homing systems.

  9. Aging analyses of aircraft wire insulation

    Energy Technology Data Exchange (ETDEWEB)

    GILLEN,KENNETH T.; CLOUGH,ROGER LEE; CELINA,MATHIAS C.; AUBERT,JAMES H.; MALONE,G. MICHAEL

    2000-05-08

    Over the past two decades, Sandia has developed a variety of specialized analytical techniques for evaluating the long-term aging and stability of cable insulation and other related materials. These techniques have been applied to cable reliability studies involving numerous insulation types and environmental factors. This work has allowed the monitoring of the occurrence and progression of cable material deterioration in application environments, and has provided insights into material degradation mechanisms. It has also allowed development of more reliable lifetime prediction methodologies. As a part of the FAA program for intrusive inspection of aircraft wiring, they are beginning to apply a battery of techniques to assessing the condition of cable specimens removed from retired aircraft. It is anticipated that in a future part of this program, they may employ these techniques in conjunction with accelerated aging methodologies and models that the authros have developed and employed in the past to predict cable lifetimes. The types of materials to be assessed include 5 different wire types: polyimide, PVC/Glass/Nylon, extruded XL-polyalkene/PVDF, Poly-X, and XL-ETFE. This presentation provides a brief overview of the main techniques that will be employed in assessing the state of health of aircraft wire insulation. The discussion will be illustrated with data from their prior cable aging studies, highlighting the methods used and their important conclusions. A few of the techniques that they employ are widely used in aging studies on polymers, but others are unique to Sandia. All of their techniques are non-proprietary, and maybe of interest for use by others in terms of application to aircraft wiring analysis. At the end of this report is a list showing some leading references to papers that have been published in the open literature which provide more detailed information on the analytical techniques for elastomer aging studies. The first step in the

  10. Aircraft vulnerability analysis by modelling and simulation

    CSIR Research Space (South Africa)

    Willers, CJ

    2014-09-01

    Full Text Available attributable to misuse of the weapon or to missile performance restrictions. This paper analyses some of the factors affecting aircraft vulnerability and demonstrates a structured analysis of the risk and aircraft vulnerability problem. The aircraft...

  11. Evaluation of long-term stability of mesiodistal axial inclinations of maxillary molars through panoramic radiographs in subjects treated with Pendulum appliance.

    Science.gov (United States)

    Rocha, Caroline Andrade; Almeida, Renato Rodrigues de; Henriques, José Fernando Castanha; Flores-Mir, Carlos; Almeida, Marcio Rodrigues de

    2016-01-01

    To evaluate the stability of mesiodistal inclination of maxillary molars produced by a pendulum appliance, five years after completion of orthodontic treatment. Angulation changes were compared to an untreated sample. The sample consisted of 20 patients (14 females and 6 males) with Class II, Division 1 malocclusion that was treated through molar distalization with a pendulum appliance followed by cervical headgear and full fixed appliances. Maxillary molar inclination was evaluated through panoramic radiograph. The mean age at pretreatment was 14.3 ± 1.6 years, whereas at immediate post-treatment it was 18.6 ± 1.8 years, and at long-term post-treatment it was 23.8 ± 2.0 years. A control group of 16 untreated individuals with untreated normocclusion ranging in age from 12 to 17 years old were used as comparison group. Data were statistically analyzed with independent t-tests and ANOVA test followed by Tukey post-hoc tests. Statistically significant differences were found between T1(94.50) and T2 (98.80) as well as between T2 and T3 (94.70) for maxillary first molars. Maxillary second molars did not show any statistically significant positional changes during the evaluated time periods T1 (107.50), T2 (109.30) and T3 (106.90). Although maxillary first molars underwent distal crown inclination immediately after treatment, approximately five years thereafter their roots tended to upright close to the pretreatment positions.

  12. A comparison of the nutritional status between adult celiac patients on a long-term, strictly gluten-free diet and healthy subjects.

    Science.gov (United States)

    Barone, M; Della Valle, N; Rosania, R; Facciorusso, A; Trotta, A; Cantatore, F P; Falco, S; Pignatiello, S; Viggiani, M T; Amoruso, A; De Filippis, R; Di Leo, A; Francavilla, R

    2016-01-01

    There are conflicting data on the effect of a gluten-free diet (GFD) on the nutritional status of celiac patients. In the present study, we evaluated, in adult celiac patients, the influence of a long-term, strictly GFD on their nutritional status and compared it with matched healthy volunteers. Our study included 39 celiac patients and 39 healthy volunteers. The body mass index (BMI) of patients and controls was evaluated at enrollment, while the patients' BMI before the GFD was retrieved from clinical records. In addition, at enrollment, in both groups, we compared BMI, fat mass (FM), bone mineral density (BMD), as well as their dietary intake, recorded on a 7-day diary. At the time of diagnosis, the majority of celiac patients (82.0%) had a normal BMI or were overweight, while 10.3% were malnourished. After the GFD, patients with a normal BMI showed a significant weight increase (P=0.002), but none of them switched in the overweight or obese category. Two (50%) of the four malnourished patients achieved a normal BMI. Controls and patients on a GFD had a similar BMI, FM, BMD and total calorie intake, but the amount of lipids and fiber intake was significantly different in the two groups (P=0.003 and Pnutritional status of celiac patients without inducing overweight or obesity. Our findings are related to a celiac population adopting a GFD based on a Mediterranean-type diet.

  13. A comparison of the medium-term impact and recovery of the Pakistan floods and the Haiti earthquake: objective and subjective measures.

    Science.gov (United States)

    Weiss, William M; Kirsch, Thomas D; Doocy, Shannon; Perrin, Paul

    2014-06-01

    The 2010 Haiti earthquake and Pakistan floods were similar in their massive human impact. Although the specific events were very different, the humanitarian response to disasters is supposed to achieve the same ends. This paper contrasts the disaster effects and aims to contrast the medium-term response. In January 2011, similarly structured population-based surveys were carried out in the most affected areas using stratified cluster designs (80×20 in Pakistan and 60×20 in Haiti) with probability proportional to size sampling. Displacement persisted in Haiti and Pakistan at 53% and 39% of households, respectively. In Pakistan, 95% of households reported damage to their homes and loss of income or livelihoods, and in Haiti, the rates were 93% and 85%, respectively. Frequency of displacement, and income or livelihood loss, were significantly higher in Pakistan, whereas disaster-related deaths or injuries were significantly more prevalent in Haiti. Given the rise in disaster frequency and costs, and the volatility of humanitarian funding streams as a result of the recent global financial crisis, it is increasingly important to measure the impact of humanitarian response against the goal of a return to normalcy.

  14. Advanced energy systems (APU) for large commercial aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Westenberger, A.; Bleil, J.; Arendt, M. [Airbus Deutschland GmbH, Hamburg (Germany)

    2013-06-01

    The intention of using a highly integrated component using on fuel cell technology installed on board of large commercial passenger aircraft for the generation of onboard power for the systems demand during an entire aircraft mission was subject of several studies. The results of these studies have been based on the simulation of the whole system in the context of an aircraft system environment. In front of the work stood the analyses of different fuel cell technologies and the analyses of the aircraft system environment. Today onboard power is provided on ground by an APU and in flight by the main engines. In order to compare fuel cell technology with the today's usual gas turbine operational characteristics have been analysed. A second analysis was devoted to the system demand for typical aircraft categories. The MEA system concept was supposed in all cases. The favourable concept represented an aircraft propelled by conventional engines with starter generator units, providing AC electrical power, covering in total proximately half of the power demand and a component based on fuel cell technology. This component provided electrical DC power, clean potable water, thermal energy at 180 degrees Celsius and nitrogen enriched air for fire suppression and fire extinguishing agent. In opposite of a usual gas turbine based APU, this new unit was operated as the primary power system. (orig.)

  15. Evaluation of long-term stability of mesiodistal axial inclinations of maxillary molars through panoramic radiographs in subjects treated with Pendulum appliance

    Directory of Open Access Journals (Sweden)

    Caroline Andrade Rocha

    2016-02-01

    Full Text Available Objective: To evaluate the stability of mesiodistal inclination of maxillary molars produced by a pendulum appliance, five years after completion of orthodontic treatment. Angulation changes were compared to an untreated sample. Methods: The sample consisted of 20 patients (14 females and 6 males with Class II, Division 1 malocclusion that was treated through molar distalization with a pendulum appliance followed by cervical headgear and full fixed appliances. Maxillary molar inclination was evaluated through panoramic radiograph. The mean age at pretreatment was 14.3 ± 1.6 years, whereas at immediate post-treatment it was 18.6 ± 1.8 years, and at long-term post-treatment it was 23.8 ± 2.0 years. A control group of 16 untreated individuals with untreated normocclusion ranging in age from 12 to 17 years old were used as comparison group. Data were statistically analyzed with independent t-tests and ANOVA test followed by Tukey post-hoc tests. Results: Statistically significant differences were found between T1(94.50 and T2 (98.80 as well as between T2 and T3 (94.70 for maxillary first molars. Maxillary second molars did not show any statistically significant positional changes during the evaluated time periods T1 (107.50, T2 (109.30 and T3 (106.90. Conclusion: Although maxillary first molars underwent distal crown inclination immediately after treatment, approximately five years thereafter their roots tended to upright close to the pretreatment positions.

  16. Evaluation of long-term stability of mesiodistal axial inclinations of maxillary molars through panoramic radiographs in subjects treated with Pendulum appliance

    Science.gov (United States)

    Rocha, Caroline Andrade; de Almeida, Renato Rodrigues; Henriques, José Fernando Castanha; Flores-Mir, Carlos; de Almeida, Marcio Rodrigues

    2016-01-01

    Objective: To evaluate the stability of mesiodistal inclination of maxillary molars produced by a pendulum appliance, five years after completion of orthodontic treatment. Angulation changes were compared to an untreated sample. Methods: The sample consisted of 20 patients (14 females and 6 males) with Class II, Division 1 malocclusion that was treated through molar distalization with a pendulum appliance followed by cervical headgear and full fixed appliances. Maxillary molar inclination was evaluated through panoramic radiograph. The mean age at pretreatment was 14.3 ± 1.6 years, whereas at immediate post-treatment it was 18.6 ± 1.8 years, and at long-term post-treatment it was 23.8 ± 2.0 years. A control group of 16 untreated individuals with untreated normocclusion ranging in age from 12 to 17 years old were used as comparison group. Data were statistically analyzed with independent t-tests and ANOVA test followed by Tukey post-hoc tests. Results: Statistically significant differences were found between T1(94.50) and T2 (98.80) as well as between T2 and T3 (94.70) for maxillary first molars. Maxillary second molars did not show any statistically significant positional changes during the evaluated time periods T1 (107.50), T2 (109.30) and T3 (106.90). Conclusion: Although maxillary first molars underwent distal crown inclination immediately after treatment, approximately five years thereafter their roots tended to upright close to the pretreatment positions. PMID:27007764

  17. Short-term effects of sports taping on navicular height, navicular drop and peak plantar pressure in healthy elite athletes: A within-subject comparison.

    Science.gov (United States)

    Kim, Taegyu; Park, Jong-Chul

    2017-11-01

    Medial tibial stress syndrome (MTSS) is one of the most common exercise-induced leg pain. The navicular drop (ND) was identified as a risk factor for MTSS. This study aimed to evaluate the short-term effects of sports taping applied to the supporting lower leg during sitting, standing, walking, and jogging to restrict the ND in healthy elite athletes.Twenty-four healthy elite athletes without a history of exercise-induced pain or injuries in the lower limbs participated in this study (median age: 21.00 years; 1st--3rd quartiles; 19.25-22.00). The 4 taping conditions were used: rigid taping (RT), kinesiology taping (KT), placebo taping (PT), and non-taping (NT). The order of taping techniques was randomly assigned. Normalized navicular height (NH), ND, and normalized ND evaluated using 3-dimensional motion analysis, and normalized peak plantar pressure (PP) were compared in 4 taping conditions during sitting, standing, walking, and jogging.During sitting, the normalized NH of RT is higher than that of NT, KT, and PT (χ = 17.30, P = .001), while during jogging, the normalized NH of RT is higher than that of NT and PT (χ = 10.55, P = .014). The normalized peak PP of NT is higher than that of PT (χ = 8.871, P = .031) in the lateral midfoot region.This study showed the RT technique maintained NH during sitting and jogging, and the RT technique could be an effective preventive and treatment strategy for MTSS.

  18. ERGONOMIC DESIGN OF AIRCRAFT COCKPIT

    Directory of Open Access Journals (Sweden)

    CÎMPIAN Ionuţ

    2011-06-01

    Full Text Available This paper presents a model for an ergonomic design of an aircraft cockpit with the specification and verification with respect to the new European Aviation Safety Agency (EASA and Federal Aviation Administration (FAA requirements. The goal is to expressing the concepts on which the aircraft cockpit design is based.

  19. ERGONOMIC DESIGN OF AIRCRAFT COCKPIT

    Directory of Open Access Journals (Sweden)

    CÎMPIAN Ionuţ

    2012-09-01

    Full Text Available This paper presents a model for an ergonomic design of an aircraft cockpit with the specification and verification with respect to the new European Aviation Safety Agency (EASA and Federal Aviation Administration (FAA requirements. The goal is to expressing the concepts on which the aircraft cockpit design are based.

  20. Modeling Vibration Intensity of Aircraft Bevel Gears

    Directory of Open Access Journals (Sweden)

    V. V. Golovanov

    2017-01-01

    Full Text Available The subject is the aircraft bevel gears, which are part of the drive systems of gas turbine engines and helicopter transmissions. The article deals with defect specifics of the aircraft conical gears with a circular tooth as compared to the conical gear wheels of general engineering. The finite element method has been used to find by calculation that the main reason for destruction of aircraft bevel gears is a resonant vibration excitation of the gear wheel rim due to its nodal diameter eigenvibrations happened to be within the operating range of the transmission rotation frequencies. A parametric finite element model has been developed. It allows us to investigate the impact of modification parameters of the drive side of gear wheels on the function of the kinematic transmission error at different values of transmitted torque. Using the method of main coordinates, a reduced dynamic model of the bevel gear has been developed to allow simulating the vibration intensity of bevel gears with various parameters of the working profile modification. Within the framework of evaluation test of the dynamic model, amplitude-frequency characteristics have been constructed for the main parameters of transmission oscillations, including vibrational stresses in the teeth space. It is found that modification parameters of the transmission drive side have a significant effect on the vibration intensity of the bevel gears in the entire operating range. The main factor affecting the vibration stress amplitude in the gear wheel is the amplitude of the kinematic error function with the corresponding torque transmitted. The obtained research results can be used when designing the new aircraft drives and modernizing the existing ones. As part of the further development, it is expected to create a technique for recording the damage accumulation in the conical gears, taking into account the typical flight profile of a gas turbine engine or a helicopter.

  1. 77 FR 45480 - Deductions for Entertainment Use of Business Aircraft

    Science.gov (United States)

    2012-08-01

    ... Part 1 [TD 9597] RIN 1545-BF34 Deductions for Entertainment Use of Business Aircraft AGENCY: Internal... Disallowance to Expenses The proposed regulations provide that the disallowance provisions are applied on a pro... applied to total expenses subject to disallowance on a pro rata basis. The final regulations include an...

  2. Reinterpreting aircraft measurements in anisotropic scaling turbulence

    Directory of Open Access Journals (Sweden)

    S. J. Hovde

    2009-07-01

    .4, 0.73. The latter being very close to those estimated by drop sondes (2.4, 0.75 in the vertical direction. In addition, for each leg we estimate the energy flux, the sphero-scale and the critical transition scale. The latter varies quite widely from scales of kilometers to greater than several hundred kilometers. The overall conclusion is that up to the critical scale, the aircraft follows a fractal trajectory which may increase the intermittency of the measurements, but doesn't strongly affect the scaling exponents whereas for scales larger than the critical scale, the aircraft follows isobars whose exponents are different from those along isoheights (and equal to the vertical exponent perpendicular to the isoheights. We bolster this interpretation by considering the absolute slopes (|Δzx| of the aircraft as a function of lag Δx and of scale invariant lag Δxz1/Hz.

    We then revisit four earlier aircraft campaigns including GASP and MOZAIC showing that they all have nearly identical transitions and can thus be easily explained by the proposed combination of altitude/wind in an anisotropic but scaling turbulence. Finally, we argue that this reinterpretation in terms of wide range anisotropic scaling is compatible with atmospheric phenomenology including convection.

  3. Trends in aircraft noise annoyance: The role of study and sample characteristics

    NARCIS (Netherlands)

    Kroesen, M.; Molin, E.J.E.; Miedema, H.M.E.; Vos, H.; Janssen, S.A.; Wee, B. van

    2010-01-01

    This study assesses the effects of aircraft noise on residential satisfaction, an important indicator of subjective well-being. A structural equation model is specified that estimates the relationships between objective variables, noise annoyance variables and residential satisfaction. Secondary

  4. 76 FR 5 - Feathering Propeller Systems for Light-Sport Aircraft Powered Gliders

    Science.gov (United States)

    2011-01-03

    ... Aircraft Powered Gliders AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule; request... aircraft by removing ``auto'' from the term ``autofeathering'' as it applies to powered gliders. This amendment will allow both manual and autofeathering propeller operation for powered gliders that qualify as...

  5. Commercial aircraft composite technology

    CERN Document Server

    Breuer, Ulf Paul

    2016-01-01

    This book is based on lectures held at the faculty of mechanical engineering at the Technical University of Kaiserslautern. The focus is on the central theme of societies overall aircraft requirements to specific material requirements and highlights the most important advantages and challenges of carbon fiber reinforced plastics (CFRP) compared to conventional materials. As it is fundamental to decide on the right material at the right place early on the main activities and milestones of the development and certification process and the systematic of defining clear requirements are discussed. The process of material qualification - verifying material requirements is explained in detail. All state-of-the-art composite manufacturing technologies are described, including changes and complemented by examples, and their improvement potential for future applications is discussed. Tangible case studies of high lift and wing structures emphasize the specific advantages and challenges of composite technology. Finally,...

  6. Overview of NASA Electrified Aircraft Propulsion Research for Large Subsonic Transports

    Science.gov (United States)

    Jansen, Ralph H.; Bowman, Cheryl; Jankovsky, Amy; Dyson, Rodger; Felder, James L.

    2017-01-01

    NASA is investing in Electrified Aircraft Propulsion (EAP) research as part of the portfolio to improve the fuel efficiency, emissions, and noise levels in commercial transport aircraft. Turboelectric, partially turboelectric, and hybrid electric propulsion systems are the primary EAP configurations being evaluated for regional jet and larger aircraft. The goal is to show that one or more viable EAP concepts exist for narrow body aircraft and mature tall-pole technologies related to those concepts. A summary of the aircraft system studies, technology development, and facility development is provided. The leading concept for mid-term (2035) introduction of EAP for a single aisle aircraft is a tube and wing, partially turbo electric configuration (STARC-ABL), however other viable configurations exist. Investments are being made to raise the TRL (Technology Readiness Level) level of light weight, high efficiency motors, generators, and electrical power distribution systems as well as to define the optimal turbine and boundary layer ingestion systems for a mid-term tube and wing configuration. An electric aircraft power system test facility (NEAT - NASA’s Electric Aircraft Testbed) is under construction at NASA Glenn and an electric aircraft control system test facility (HEIST - Hybrid-Electric Integrated Systems Testbed) is under construction at NASA Armstrong. The correct building blocks are in place to have a viable, large plane EAP configuration tested by 2025 leading to entry into service in 2035 if the community chooses to pursue that goal.

  7. SUBJECT INDEX

    Indian Academy of Sciences (India)

    Subject Index. Variation of surface electric field during geomagnetic disturbed period at Maitri, Antarctica. 1721. Geomorphology. A simple depression-filling method for raster and irregular elevation datasets. 1653. Decision Support System integrated with Geographic. Information System to target restoration actions in water-.

  8. Aircraft gas turbine materials and processes.

    Science.gov (United States)

    Kear, B H; Thompson, E R

    1980-05-23

    Materials and processing innovations that have been incorporated into the manufacture of critical components for high-performance aircraft gas turbine engines are described. The materials of interest are the nickel- and cobalt-base superalloys for turbine and burner sections of the engine, and titanium alloys and composites for compressor and fan sections of the engine. Advanced processing methods considered include directional solidification, hot isostatic pressing, superplastic foring, directional recrystallization, and diffusion brazing. Future trends in gas turbine technology are discussed in terms of materials availability, substitution, and further advances in air-cooled hardware.

  9. Aircraft Rotor Surface Coating Qualification Testing Aircraft Rotor Surface Coating

    National Research Council Canada - National Science Library

    2006-01-01

    .... The Aviation and Missile Research, Development and Engineering Center "AMRDEC" located at Redstone Arsenal, AL selected the NCDMM to coordinate the initial effort to qualify a new aircraft rotor...

  10. 48 CFR 246.408-71 - Aircraft.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Aircraft. 246.408-71... Aircraft. (a) The Federal Aviation Administration (FAA) has certain responsibilities and prerogatives in connection with some commercial aircraft and of aircraft equipment and accessories (Pub. L. 85-726 (72 Stat...

  11. 14 CFR 63.33 - Aircraft ratings.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aircraft ratings. 63.33 Section 63.33... CERTIFICATION: FLIGHT CREWMEMBERS OTHER THAN PILOTS Flight Engineers § 63.33 Aircraft ratings. (a) The aircraft...) Turbopropeller powered; and (3) Turbojet powered. (b) To be eligible for an additional aircraft class rating...

  12. 14 CFR 141.39 - Aircraft.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Aircraft. 141.39 Section 141.39 Aeronautics... CERTIFICATED AGENCIES PILOT SCHOOLS Personnel, Aircraft, and Facilities Requirements § 141.39 Aircraft. (a... certificate or provisional pilot school certificate must show that each aircraft used by the school for flight...

  13. 36 CFR 331.14 - Aircraft.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Aircraft. 331.14 Section 331..., KENTUCKY AND INDIANA § 331.14 Aircraft. (a) The operation of aircraft on WCA lands and waters is prohibited... prohibited. (c) The provisions of this section shall not be applicable to aircraft engaged on official...

  14. 40 CFR 87.6 - Aircraft safety.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Aircraft safety. 87.6 Section 87.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF AIR POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES General Provisions § 87.6 Aircraft safety. The provisions of...

  15. 14 CFR 252.13 - Small aircraft.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Small aircraft. 252.13 Section 252.13 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.13 Small aircraft. Air carriers shall prohibit smoking on aircraft...

  16. 36 CFR 327.4 - Aircraft.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Aircraft. 327.4 Section 327.4... Aircraft. (a) This section pertains to all aircraft including, but not limited to, airplanes, seaplanes, helicopters, ultra-light aircraft, motorized hang gliders, hot air balloons, any non-powered flight devices or...

  17. Short-term red wine consumption promotes differential effects on plasma levels of high-density lipoprotein cholesterol, sympathetic activity, and endothelial function in hypercholesterolemic, hypertensive, and healthy subjects

    Directory of Open Access Journals (Sweden)

    Ana CM Andrade

    2009-05-01

    Full Text Available OBJECTIVES: To compare the metabolic, hemodynamic, autonomic, and endothelial responses to short-term red wine consumption in subjects with hypercholesterolemia or arterial hypertension, and healthy controls. METHODS: Subjects with hypercholesterolemia (n=10 or arterial hypertension (n=9, or healthy controls (n=7 were given red wine (250 mL/night for 15 days. Analyses were performed before and after red wine intake. RESULTS: Red wine significantly increased the plasma levels of HDL-cholesterol in the controls, but not in the other groups. The effects on hemodynamic measurements were mild, non-significantly more prominent in healthy subjects, and exhibited high interindividual variability. Across all participants, mean blood pressure decreased 7 mmHg (p <0.01 and systemic vascular resistance decreased 7% (p = 0.05. Heart rate and cardiac output did not significantly change in any group. Red wine enhanced muscle sympathetic fibular nerve activity in hypercholesterolemic and hypertensive patients, but not in controls. At baseline, brachial artery flow-mediated dilation was impaired in patients with hypercholesterolemia and arterial hypertension; red wine restored the dilation in the hypercholesterolemic group but not in the hypertensive group. CONCLUSIONS: Red wine elicits different metabolic, autonomic, and endothelial responses among individuals with hypercholesterolemia or arterial hypertension and healthy controls. Our findings highlight the need to consider patient characteristics when evaluating the response to red wine.

  18. 76 FR 76686 - Notification and Reporting of Aircraft Accidents or Incidents and Overdue Aircraft, and...

    Science.gov (United States)

    2011-12-08

    ... and Reporting of Aircraft Accidents or Incidents and Overdue Aircraft, and Preservation of Aircraft... reporting requirements with regard to aircraft accidents or incidents, found at paragraph (a)(10) of section... final rule entitled, ``Notification and Reporting of Aircraft Accidents or Incidents and Overdue...

  19. Aircraft of Today. [Aerospace Education I. Instructor Handbook.

    Science.gov (United States)

    Air Univ., Maxwell AFB, AL. Junior Reserve Office Training Corps.

    This publication is prepared to accompany the textbook entitled "Aircraft of Today," published in the Aerospace Education I series. The curriculum guide provides guidelines for teachers in terms of various concepts stressed in each chapter and suggested methodology for instruction. The subdivisions in the guidebook for each chapter…

  20. Parameter estimation of an aeroelastic aircraft using neural networks

    Indian Academy of Sciences (India)

    e-mail: scr@iitk.ac.in. Abstract. Application of neural networks to the problem of aerodynamic modelling and parameter estimation for aeroelastic aircraft is addressed. A neural model capable of ... of the network in terms of the number of neurons in the hidden layer, the learning rate, the momentum rate etc. is not an exact ...

  1. VTOL to Transonic Aircraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The cyclogyro, an aircraft propulsion concept with the potential for VTOL to the lower bounds of transonic flight, is conceptually simple but structurally and...

  2. Unmanned Aircraft Systems - Raw Photography

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The USGS National Unmanned Aircraft Systems (UAS) Project Office utilizes UAS technology for collecting remote sensing data on a local scale. Typical UAS projects...

  3. Fire resistant aircraft seat program

    Science.gov (United States)

    Fewell, L. A.

    1979-01-01

    Foams, textiles, and thermoformable plastics were tested to determine which materials were fire retardant, and safe for aircraft passenger seats. Seat components investigated were the decorative fabric cover, slip covers, fire blocking layer, cushion reinforcement, and the cushioning layer.

  4. Quality standard of aircraft maintenance

    Directory of Open Access Journals (Sweden)

    Боузаієнне Меккі бен Салем

    2005-01-01

    Full Text Available  The question of the account of operation conditions of an aeronautical engineering in airlines is considered at formation and a correcting of plans on aircrafts park maintenance.

  5. Aerothermodynamics of aircraft engine components

    National Research Council Canada - National Science Library

    Oates, Gordon C

    1985-01-01

    ....A45A37 1985 ISBN 0-915928-97-3 2. Aircraft gas turbines. 629.134'353 85-13355 Copyright © 1985 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved. Printed in the ...

  6. Western Pacific Typhoon Aircraft Fixes

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Western Pacific typhoon aircraft reconnaissance data from the years 1946 - 1965 and 1978, excluding 1952, were transcribed from original documents, or copy of...

  7. Lil HAL: digital kneeboard for ejection seat aircraft

    Science.gov (United States)

    Parisi, Vince

    2004-09-01

    In the last few years, airlines, commercial air carriers and the military have begun to introduce electronic tools into the cockpit to replace paper versions of flight publications, flight plans, departure and approach plates, maps, etc. These devices have varied from the common laptop to the smaller pen-tablet type computers. In some instances these devices have been connected to aircraft data buses to collect maintenance data, fault codes and other useful information. None of these devices, however, have been found satisfactory in ejection seat aircraft due to their size, weight, and dynamic characteristics when subjected to the inertial and aerodynamic forces that occur during an ejection. This paper describes an electronic digital kneeboard suitable for use in an ejection seat aircraft. The kneeboard consists of a look at helmet-mounted display, a small streamlined kneeboard input device, a carry-on/carry-off computer and its associated support interfaces.

  8. Optimal nonlinear estimation for aircraft flight control in wind shear

    Science.gov (United States)

    Mulgund, Sandeep S.

    1994-01-01

    The most recent results in an ongoing research effort at Princeton in the area of flight dynamics in wind shear are described. The first undertaking in this project was a trajectory optimization study. The flight path of a medium-haul twin-jet transport aircraft was optimized during microburst encounters on final approach. The assumed goal was to track a reference climb rate during an aborted landing, subject to a minimum airspeed constraint. The results demonstrated that the energy loss through the microburst significantly affected the qualitative nature of the optimal flight path. In microbursts of light to moderate strength, the aircraft was able to track the reference climb rate successfully. In severe microbursts, the minimum airspeed constraint in the optimization forced the aircraft to settle on a climb rate smaller than the target. A tradeoff was forced between the objectives of flight path tracking and stall prevention.

  9. Dryden B-52 Launch Aircraft in Flight over Dryden

    Science.gov (United States)

    1996-01-01

    parachute recovery systems used to recover the space shuttle solid rocket booster casings. It also supported eight orbiter (space shuttle) drag chute tests in 1990. In addition, the B-52 served as the air launch platform for the first six Pegasus space boosters. During its many years of service, the B-52 has undergone several modifications. The first major modification was made by North American Aviation (now part of Boeing) in support of the X-15 program. This involved creating a launch-panel-operator station for monitoring the status of the test vehicle being carried, cutting a large notch in the right inboard wing flap to accommodate the vertical tail of the X-15 aircraft, and installing a wing pylon that enables the B-52 to carry research vehicles and test articles to be air-launched/dropped. Located on the right wing, between the inboard engine pylon and the fuselage, this wing pylon was subjected to extensive testing prior to its use. For each test vehicle the B-52 carried, minor changes were made to the launch-panel operator's station. Built originally by the Boeing Company, the NASA B-52 is powered by eight Pratt & Whitney J57-19 turbojet engines, each of which produce 12,000 pounds of thrust. The aircraft's normal launch speed has been Mach 0.8 (about 530 miles per hour) and its normal drop altitude has been 40,000 to 45,000 feet. It is 156 feet long and has a wing span of 185 feet. The heaviest load it has carried was the No. 2 X-15 aircraft at 53,100 pounds. Project manager for the aircraft is Roy Bryant.

  10. Aircraft ditching loads simulation tool

    OpenAIRE

    Bonanni, A.; Vandewaeter, L.; Havill, C.; Kanyoo, P.; Taunton, D.J.; Blake, J.I.R.; Cropper, E.; Hancock, S.

    2015-01-01

    The present work presents a novel methodology developed for calculating the steady loads acting on aircraft structures in the event of ditching in water. It represents the preliminary result of Stirling Dynamics as part of a NATEP research project. The overall objective of the project is to expand the capabilities of the Stirling Dynamics proprietary software SD-GLOAD (originally designed for ground and crash loads dynamic simulations) to aircraft ditching simulations. The methodology present...

  11. Optimization in fractional aircraft ownership

    Science.gov (United States)

    Septiani, R. D.; Pasaribu, H. M.; Soewono, E.; Fayalita, R. A.

    2012-05-01

    Fractional Aircraft Ownership is a new concept in flight ownership management system where each individual or corporation may own a fraction of an aircraft. In this system, the owners have privilege to schedule their flight according to their needs. Fractional management companies (FMC) manages all aspects of aircraft operations, including utilization of FMC's aircraft in combination of outsourced aircrafts. This gives the owners the right to enjoy the benefits of private aviations. However, FMC may have complicated business requirements that neither commercial airlines nor charter airlines faces. Here, optimization models are constructed to minimize the number of aircrafts in order to maximize the profit and to minimize the daily operating cost. In this paper, three kinds of demand scenarios are made to represent different flight operations from different types of fractional owners. The problems are formulated as an optimization of profit and a daily operational cost to find the optimum flight assignments satisfying the weekly and daily demand respectively from the owners. Numerical results are obtained by Genetic Algorithm method.

  12. Aircraft exhaust sulfur emissions

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R.C.; Anderson, M.R.; Miake-Lye, R.C.; Kolb, C.E. [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics; Sorokin, A.A.; Buriko, Y.I. [Scientific Research Center `Ecolen`, Moscow (Russian Federation)

    1997-12-31

    The extent to which fuel sulfur is converted to SO{sub 3} during combustion and the subsequent turbine flow in supersonic and subsonic aircraft engines is estimated numerically. The analysis is based on: a flamelet model with non-equilibrium sulfur chemistry for the combustor, and a one-dimensional, two-stream model with finite rate chemical kinetics for the turbine. The results indicate that between 2% and 10% of the fuel sulfur is emitted as SO{sub 3}. It is also shown that, for a high fuel sulfur mass loading, conversion in the turbine is limited by the level of atomic oxygen at the combustor exit, leading to higher SO{sub 2} oxidation efficiency at lower fuel sulfur loadings. While SO{sub 2} and SO{sub 3} are the primary oxidation products, the model results further indicate H{sub 2}SO{sub 4} levels on the order of 0.1 ppm for supersonic expansions through a divergent nozzle. This source of fully oxidized S(6) (SO{sub 3} + H{sub 2}SO{sub 4}) exceeds previously calculated S(6) levels due to oxidation of SO{sub 2} by OH in the exhaust plume outside the engine nozzle. (author) 26 refs.

  13. Innovations in Aircraft Design

    Science.gov (United States)

    1997-01-01

    The Boeing 777 carries with it basic and applied research, technology, and aerodynamic knowledge honed at several NASA field centers. Several Langley Research Center innovations instrumental to the development of the aircraft include knowledge of how to reduce engine and other noise for passengers and terminal residents, increased use of lightweight aerospace composite structures for increased fuel efficiency and range, and wind tunnel tests confirming the structural integrity of 777 wing-airframe integration. Test results from Marshall Space Flight Center aimed at improving the performance of the Space Shuttle engines led to improvements in the airplane's new, more efficient jet engines. Finally, fostered by Ames Research Center, the Boeing 777 blankets that protect areas of the plane from high temperatures and fire have a lineage to Advanced Flexible Reusable Surface Insulation used on certain areas of the Space Shuttle. According to Boeing Company estimates, the 777 has captured three-quarters of new orders for airplanes in its class since the program was launched.

  14. Fractographic examination of coupons representing aircraft structural joints with and without hole cold expansion

    National Research Council Canada - National Science Library

    Yanishevsky, Marko; Li, Gang; Shi, Guoqin; Backman, David S

    2013-01-01

    In an effort to establish the potential benefits of hole cold expansion and interference fit fasteners for long term fatigue performance, coupons representing three types of aircraft structural joints...

  15. Ball lightning risk to aircraft

    Science.gov (United States)

    Doe, R.; Keul, A.

    2009-04-01

    Lightning is a rare but regular phenomenon for air traffic. Aircraft are designed to withstand lightning strikes. Research on lightning and aircraft can be called detailed and effective. In the last 57 years, 18 reported lightning aviation disasters with a fatality figure of at least 714 persons occurred. For comparison, the last JACDEC ten-year average fatality figure was 857. The majority encountered lightning in the climb, descent, approach and/or landing phase. Ball lightning, a metastable, rare lightning type, is also seen from and even within aircraft, but former research only reported individual incidents and did not generate a more detailed picture to ascertain whether it constitutes a significant threat to passenger and aircraft safety. Lacking established incident report channels, observations were often only passed on as "air-travel lore". In an effort to change this unsatisfactory condition, the authors have collected a first international dataset of 38 documented ball lightning aircraft incidents from 1938 to 2001 involving 13 reports over Europe, 13 over USA/Canada, and 7 over Russia. 18 (47%) reported ball lightning outside the aircraft, 18 (47%) inside, 2 cases lacked data. 8 objects caused minor damage, 8 major damage (total: 42%), only one a crash. No damage was reported in 18 cases. 3 objects caused minor crew injury. In most cases, ball lightning lasted several seconds. 11 (29%) incidents ended with an explosion of the object. A cloud-aircraft lightning flash was seen in only 9 cases (24%) of the data set. From the detailed accounts of air personnel in the last 70 years, it is evident that ball lightning is rarely, but consistently observed in connection with aircraft and can also occur inside the airframe. Reports often came from multiple professional witnesses and in several cases, damages were investigated by civil or military authorities. Although ball lightning is no main air traffic risk, the authors suggest that incident and accident

  16. Overview of NASA Electrified Aircraft Propulsion Research for Large Subsonic Transports

    Science.gov (United States)

    Jansen, Ralph H.; Bowman, Cheryl; Jankovsky, Amy; Dyson, Rodger; Felder, James

    2017-01-01

    NASA is investing in Electrified Aircraft Propulsion (EAP) research as part of the portfolio to improve the fuel efficiency, emissions, and noise levels in commercial transport aircraft. Turboelectric, partially turboelectric, and hybrid electric propulsion systems are the primary EAP configurations being evaluated for regional jet and larger aircraft. The goal is to show that one or more viable EAP concepts exist for narrow body aircraft and mature tall-pole technologies related to those concepts. A summary of the aircraft system studies, technology development, and facility development is provided. The leading concept for mid-term (2035) introduction of EAP for a single aisle aircraft is a tube and wing, partially turbo electric configuration (STARC-ABL), however other viable configurations exist. Investments are being made to raise the TRL level of light weight, high efficiency motors, generators, and electrical power distribution systems as well as to define the optimal turbine and boundary layer ingestion systems for a mid-term tube and wing configuration. An electric aircraft power system test facility (NEAT) is under construction at NASA Glenn and an electric aircraft control system test facility (HEIST) is under construction at NASA Armstrong. The correct building blocks are in place to have a viable, large plane EAP configuration tested by 2025 leading to entry into service in 2035 if the community chooses to pursue that goal.

  17. Environmental compatibility of CRYOPLANE the cryogenic-fuel aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Klug, H.G. [Daimler Benz Aerospace Airbus, Hamburg (Germany)

    1997-12-31

    `CRYOPLANE` is the project name for an aircraft powered by cryogenic fuel, either liquid natural gas (LNG, mainly consisting of methane) or liquid hydrogen (LH{sub 2}). Emission of CO{sub 2}, unburnt hydrocarbons, soot and sulfur will be completely avoided by hydrogen combustion: LH{sub 2} is an extremely pure liquid. Emission of water as a primary combustion product is increased by a factor of 2.6. Exhaust gases behind hydrogen engines contain more water than behind kerosene engines, and hence can form contrails under a wider range of atmospheric conditions. Liquid hydrogen fueled aircraft promise big advantages relative to kerosene aircraft in terms of environmental compatibility. (R.P.)

  18. Engine Conceptual Design Studies for a Hybrid Wing Body Aircraft

    Science.gov (United States)

    Tong, Michael T.; Jones, Scott M.; Haller, William J.; Handschuh, Robert F.

    2009-01-01

    Worldwide concerns of air quality and climate change have made environmental protection one of the most critical issues in aviation today. NASA s current Fundamental Aeronautics Research program is directed at three generations of aircraft in the near, mid and far term, with initial operating capability around 2015, 2020, and 2030, respectively. Each generation has associated goals for fuel burn, NOx, noise, and field-length reductions relative to today s aircrafts. The research for the 2020 generation is directed at enabling a hybrid wing body (HWB) aircraft to meet NASA s aggressive technology goals. This paper presents the conceptual cycle and mechanical designs of the two engine concepts, podded and embedded systems, which were proposed for a HWB cargo freighter. They are expected to offer significant benefits in noise reductions without compromising the fuel burn.

  19. Dryden B-52 Launch Aircraft on Edwards AFB Runway

    Science.gov (United States)

    1996-01-01

    booster casings. It also supported eight orbiter (space shuttle) drag chute tests in 1990. In addition, the B-52 served as the air launch platform for the first six Pegasus space boosters. During its many years of service, the B-52 has undergone several modifications. The first major modification was made by North American Aviation (now part of Boeing) in support of the X-15 program. This involved creating a launch-panel-operator station for monitoring the status of the test vehicle being carried, cutting a large notch in the right inboard wing flap to accommodate the vertical tail of the X-15 aircraft, and installing a wing pylon that enables the B-52 to carry research vehicles and test articles to be air-launched/dropped. Located on the right wing, between the inboard engine pylon and the fuselage, this wing pylon was subjected to extensive testing prior to its use. For each test vehicle the B-52 carried, minor changes were made to the launch-panel operator's station. Built originally by the Boeing Company, the NASA B-52 is powered by eight Pratt & Whitney J57-19 turbojet engines, each of which produce 12,000 pounds of thrust. The aircraft's normal launch speed has been Mach 0.8 (about 530 miles per hour) and its normal drop altitude has been 40,000 to 45,000 feet. It is 156 feet long and has a wing span of 185 feet. The heaviest load it has carried was the No. 2 X-15 aircraft at 53,100 pounds. Project manager for the aircraft is Roy Bryant.

  20. Dryden B-52 Launch Aircraft on Dryden Ramp

    Science.gov (United States)

    1996-01-01

    booster casings. It also supported eight orbiter (space shuttle) drag chute tests in 1990. In addition, the B-52 served as the air launch platform for the first six Pegasus space boosters. During its many years of service, the B-52 has undergone several modifications. The first major modification was made by North American Aviation (now part of Boeing) in support of the X-15 program. This involved creating a launch-panel-operator station for monitoring the status of the test vehicle being carried, cutting a large notch in the right inboard wing flap to accommodate the vertical tail of the X-15 aircraft, and installing a wing pylon that enables the B-52 to carry research vehicles and test articles to be air-launched/dropped. Located on the right wing, between the inboard engine pylon and the fuselage, this wing pylon was subjected to extensive testing prior to its use. For each test vehicle the B-52 carried, minor changes were made to the launch-panel operator's station. Built originally by the Boeing Company, the NASA B-52 is powered by eight Pratt & Whitney J57-19 turbojet engines, each of which produce 12,000 pounds of thrust. The aircraft's normal launch speed has been Mach 0.8 (about 530 miles per hour) and its normal drop altitude has been 40,000 to 45,000 feet. It is 156 feet long and has a wing span of 185 feet. The heaviest load it has carried was the No. 2 X-15 aircraft at 53,100 pounds. Project manager for the aircraft is Roy Bryant.

  1. Aircraft Cabin Environmental Quality Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Gundel, Lara; Kirchstetter, Thomas; Spears, Michael; Sullivan, Douglas

    2010-05-06

    The Indoor Environment Department at Lawrence Berkeley National Laboratory (LBNL) teamed with seven universities to participate in a Federal Aviation Administration (FAA) Center of Excellence (COE) for research on environmental quality in aircraft. This report describes research performed at LBNL on selecting and evaluating sensors for monitoring environmental quality in aircraft cabins, as part of Project 7 of the FAA's COE for Airliner Cabin Environmental Research (ACER)1 effort. This part of Project 7 links to the ozone, pesticide, and incident projects for data collection and monitoring and is a component of a broader research effort on sensors by ACER. Results from UCB and LBNL's concurrent research on ozone (ACER Project 1) are found in Weschler et al., 2007; Bhangar et al. 2008; Coleman et al., 2008 and Strom-Tejsen et al., 2008. LBNL's research on pesticides (ACER Project 2) in airliner cabins is described in Maddalena and McKone (2008). This report focused on the sensors needed for normal contaminants and conditions in aircraft. The results are intended to complement and coordinate with results from other ACER members who concentrated primarily on (a) sensors for chemical and biological pollutants that might be released intentionally in aircraft; (b) integration of sensor systems; and (c) optimal location of sensors within aircraft. The parameters and sensors were selected primarily to satisfy routine monitoring needs for contaminants and conditions that commonly occur in aircraft. However, such sensor systems can also be incorporated into research programs on environmental quality in aircraft cabins.

  2. Eclipse program QF-106 aircraft

    Science.gov (United States)

    1996-01-01

    This photo shows two QF-106 aircraft that were used for the Eclipse project, both parked at the Mojave Airport in Mojave, California. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator -01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  3. Short-term test-retest-reliability of conditioned pain modulation using the cold-heat-pain method in healthy subjects and its correlation to parameters of standardized quantitative sensory testing.

    Science.gov (United States)

    Gehling, Julia; Mainka, Tina; Vollert, Jan; Pogatzki-Zahn, Esther M; Maier, Christoph; Enax-Krumova, Elena K

    2016-08-05

    Conditioned Pain Modulation (CPM) is often used to assess human descending pain inhibition. Nine different studies on the test-retest-reliability of different CPM paradigms have been published, but none of them has investigated the commonly used heat-cold-pain method. The results vary widely and therefore, reliability measures cannot be extrapolated from one CPM paradigm to another. Aim of the present study was to analyse the test-retest-reliability of the common heat-cold-pain method and its correlation to pain thresholds. We tested the short-term test-retest-reliability within 40 ± 19.9 h using a cold-water immersion (10 °C, left hand) as conditioning stimulus (CS) and heat pain (43-49 °C, pain intensity 60 ± 5 on the 101-point numeric rating scale, right forearm) as test stimulus (TS) in 25 healthy right-handed subjects (12females, 31.6 ± 14.1 years). The TS was applied 30s before (TSbefore), during (TSduring) and after (TSafter) the 60s CS. The difference between the pain ratings for TSbefore and TSduring represents the early CPM-effect, between TSbefore and TSafter the late CPM-effect. Quantitative sensory testing (QST, DFNS protocol) was performed on both sessions before the CPM assessment. paired t-tests, Intraclass correlation coefficient (ICC), standard error of measurement (SEM), smallest real difference (SRD), Pearson's correlation, Bland-Altman analysis, significance level p test-retest-reliability of the early CPM-effect using the heat-cold-pain method in healthy subjects achieved satisfying results in terms of the ICC. The SRD of the early CPM effect showed that an individual change of > 20 NRS can be attributed to a real change rather than chance. The late CPM-effect was weaker and not reliable.

  4. Bacteria that Travel: The Quality of Aircraft Water

    Science.gov (United States)

    Handschuh, Harald; Dwyer, Jean O’; Adley, Catherine C.

    2015-01-01

    The travelling population is increasing globally year on year. International tourist arrival figures reached 1087 million in 2013 and 1133 million in 2014; of which 53% and 54% respectively accounted for air transport. The water on board aircraft is sourced from surface or ground water; piped to a central filling point and distributed to each aircraft by water service vehicles at the home base or at the destination airport. The purpose of this study was to ascertain the microbial, chemical (pH; Total and Free chlorine) and physical (temperature) quality of water from two aircraft, long- and short-haul, as well as from the original water source and the water service vehicle. A total of 154 water samples were collected and analysed. Long-haul flights were found to be significantly poorer in terms of microbial quality than short haul flights (p = 0.015). Furthermore, correlation and regression analysis showed that the water service vehicle was a significant source of increased microbial load in aircraft. Microbial diversity was also demonstrated, with 37 bacterial species identified belonging to eight classes: γ-Proteobacteria; β-Proteobacteria; α-Proteobacteria; Bacilli; Actinobacteria; Flavobacteria; Sphingobacteria and Cytophaga; using phenotypic and 16S rDNA sequence-based analysis. We present a novel quantified study of aircraft-related potable water supplies. PMID:26529000

  5. Bacteria that Travel: The Quality of Aircraft Water

    Directory of Open Access Journals (Sweden)

    Harald Handschuh

    2015-10-01

    Full Text Available The travelling population is increasing globally year on year. International tourist arrival figures reached 1087 million in 2013 and 1133 million in 2014; of which 53% and 54% respectively accounted for air transport. The water on board aircraft is sourced from surface or ground water; piped to a central filling point and distributed to each aircraft by water service vehicles at the home base or at the destination airport. The purpose of this study was to ascertain the microbial, chemical (pH; Total and Free chlorine and physical (temperature quality of water from two aircraft, long- and short-haul, as well as from the original water source and the water service vehicle. A total of 154 water samples were collected and analysed. Long-haul flights were found to be significantly poorer in terms of microbial quality than short haul flights (p = 0.015. Furthermore, correlation and regression analysis showed that the water service vehicle was a significant source of increased microbial load in aircraft. Microbial diversity was also demonstrated, with 37 bacterial species identified belonging to eight classes: γ-Proteobacteria; β-Proteobacteria; α-Proteobacteria; Bacilli; Actinobacteria; Flavobacteria; Sphingobacteria and Cytophaga; using phenotypic and 16S rDNA sequence-based analysis. We present a novel quantified study of aircraft-related potable water supplies.

  6. Unifying Subjectivity and Objectivity

    Directory of Open Access Journals (Sweden)

    Murugesan Chandrasekaran

    2016-10-01

    Full Text Available The contribution of modern science to the progress of civilization is immeasurable. Even its tendency toward exclusive concentration on the objective world has had salutary effects of great value. Modern science has wiped away much that was merely superstitious or speculative. Its rejection of unfounded opinions and prejudices has helped the thinking mind question conventional beliefs, shed preferences and prejudices, and challenge established authority. But modern systems thinking inherited from natural science is the suppression of the subjective dimension of reality. Many complex systems are an attempt to define and represent all subjective experience in physical terms. The modern man has a bias towards objectivity. The powerful influence of sense impressions on his mind and thinking makes him ignore the subjective experience and consider only objective facts as a valid, legitimate and representation of reality. Observing objective factors that are physical is easier than observing subjective factors that are subtle. The mechanistic view of reality has led to the rejection of the role of the individual in social development as insignificant. The individuals determine the development of society. Their social power has its roots both in subjective factors and objective factors. Economy, politics, society, and culture are inseparable dimensions of a single integrated reality. Subject and object constitute an integrated whole. The mind sees them as separate and independent. Or it views one as completely subordinate to the other. Unbiased approach to the study of all human experiences may prove that subject and object are interdependent dimensions or elements of reality.

  7. Analysis and Testing of a Metallic Repair Applicable to Pressurized Composite Aircraft Structure

    Science.gov (United States)

    Przekop, Adam; Jegley, Dawn C.; Rouse, Marshall; Lovejoy, Andrew E.

    2014-01-01

    Development of repair technology is vital to the long-term application of new structural concepts on aircraft structure. The design, analysis, and testing of a repair concept applicable to a stiffened composite panel based on the Pultruded Rod Stitched Efficient Unitized Structure was recently completed. The damage scenario considered was a mid-bay to mid-bay saw-cut with a severed stiffener, flange, and skin. A bolted metallic repair was selected so that it could be easily applied in the operational environment. The present work describes results obtained from tension and pressure panel tests conducted to validate both the repair concept and finite element analysis techniques used in the design effort. Simulation and experimental strain and displacement results show good correlation, indicating that the finite element modeling techniques applied in the effort are an appropriate compromise between required fidelity and computational effort. Static tests under tension and pressure loadings proved that the proposed repair concept is capable of sustaining load levels that are higher than those resulting from the current working stress allowables. Furthermore, the pressure repair panel was subjected to 55,000 pressure load cycles to verify that the design can withstand a life cycle representative for a transport category aircraft. These findings enable upward revision of the stress allowables that had been kept at an overly-conservative level due to concerns associated with repairability of the panels. This conclusion enables more weight efficient structural designs utilizing the composite concept under investigation.

  8. International energy: Subject thesaurus supplement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    This is a supplement to International Energy: Subject Thesaurus (ETDE/PUB--2(Rev.1)), which replaced DOE/TIC-7000--the EDB Subject Thesaurus. This supplement is provided periodically to keep International Energy: Subject Thesaurus recipients up-to-date on valid vocabulary terms (descriptors) used in building and maintaining several international energy information databases. Each issue contains all new terms added since the publication of the Thesaurus. Each supplement is a cumulative listing of the new terms, so that each issue replaces the previous one.

  9. Algorithm project weight calculation aircraft

    Directory of Open Access Journals (Sweden)

    Г. В. Абрамова

    2013-07-01

    Full Text Available The paper describes the process of a complex technical object design on the example of the aircraft, using information technology such as CAD/CAM/CAE-systems, presents the basic models of aircraft which are developed in the process of designing and reflect the different aspects of its structure and function. The idea of control parametric model at complex technical object design is entered, which is a set of initial data for the development of design stations and enables the optimal complex technical object control at all stages of design using modern computer technology. The paper discloses a process of weight design, which is associated with all stages of development aircraft and its production. Usage of a scheduling algorithm that allows to organize weight calculations are carried out at various stages of planning and weighing options to optimize the use of available database of formulas and methods of calculation

  10. Aircraft Skin Restoration and Evaluation

    Science.gov (United States)

    Yandouzi, M.; Gaydos, S.; Guo, D.; Ghelichi, R.; Jodoin, B.

    2014-12-01

    The recent development of the cold spray technology has made possible the deposition of low porosity and oxide-free coatings with good adhesion and with almost no change in the microstructure of the coated parts. This focuses on the use of low-pressure cold spray process to repair damaged Al-based aircraft skin, aiming at obtaining dense coatings with strong adhesion to the Al2024-T3 alloy. In order to prove the feasibility of using of the cold spray process as a repair process for aircraft skin, series of characterisation/tests including microstructures, microhardness, adhesion strength, three-point bending, surface finish, fatigue test, and corrosion resistance were performed. The obtained results revealed that the low-pressure cold spray process is a suitable for the repair of aircraft skin.

  11. Aircraft Engine Crankshaft Optimisation

    Directory of Open Access Journals (Sweden)

    Vopařil Jan

    2014-10-01

    Full Text Available This article presents part of the crankshaft development of a two-stroke compression-ignition engine with contra-running pistons where, for invariably specified diameters and pin lengths, the optimal crankshaft shape is searched for. The process of creating several options which are then subjected to critical evaluation followed by the selection mechanism for the final best possible design is described.

  12. Aircraft Survivability. Fall 2011

    Science.gov (United States)

    2011-01-01

    Assembly Styrofoam Guides Figure 1 Example Missile Configuration for Gas-Gun Launch Figure 3 Missile Positioned in the Center of the Static Test Arena A...updated threat models to predict missile penetration and damage to a simple multi- plate array. The multi- plate array will be fabricated and subjected...Flowing to the Instrumentation Shelter at ARL Figure 5 Predictions of Missile Penetration into Multi- Plate Array 9 A ir cr af t S ur vi va bi li ty

  13. Using alternative feedback strategies to improve aircraft inspection performance

    Science.gov (United States)

    Kaewkuekool, Sittichai

    The aircraft inspection and maintenance system consists of several interrelated human and machine components, with visual inspection playing a significant role in ensuring aircraft safety. Training has been identified as one of the most important intervention strategies for enhancing the quality and reliability of aircraft inspection. This process has the potential to be improved using advancements in computer technology, especially virtual reality (VR) technology, which is becoming increasingly more affordable and prevalent. In light of this situation, this study investigated the use of VR technology to support training in the improvement of aircraft inspection performance. An experiment was developed to investigate the use of performance and process feedback in both statistical and graphical forms in two different task environments. In addition, information on defect criticality, defect location, and occurrence of defect was provided to subjects to study the effectiveness of feedforward information on inspection performance. Specifically, the experiment involved the inspection of an aircraft cargo bay using VR technology with eye tracking movement devices and a 6 degree of freedom mouse for pointing and clicking on defects. Results from the feedback training indicated that providing process along with performance feedback improved inspection performance as evidenced in the speed, accuracy and search strategy measures. Similar results were shown for both task environments. However, the addition feedforward information in the heterogeneous task environment yielded ever better inspection performance, and process and performance feedback coupled with feedforward information on defect criticality, defect location, and occurrence of defect yielded the best inspection performance as seen in the speed, accuracy and search strategy measures. The findings of this study indicate that using a combination of training intervention strategies leads to an improvement in

  14. Future aircraft networks and schedules

    Science.gov (United States)

    Shu, Yan

    2011-07-01

    Because of the importance of air transportation scheduling, the emergence of small aircraft and the vision of future fuel-efficient aircraft, this thesis has focused on the study of aircraft scheduling and network design involving multiple types of aircraft and flight services. It develops models and solution algorithms for the schedule design problem and analyzes the computational results. First, based on the current development of small aircraft and on-demand flight services, this thesis expands a business model for integrating on-demand flight services with the traditional scheduled flight services. This thesis proposes a three-step approach to the design of aircraft schedules and networks from scratch under the model. In the first step, both a frequency assignment model for scheduled flights that incorporates a passenger path choice model and a frequency assignment model for on-demand flights that incorporates a passenger mode choice model are created. In the second step, a rough fleet assignment model that determines a set of flight legs, each of which is assigned an aircraft type and a rough departure time is constructed. In the third step, a timetable model that determines an exact departure time for each flight leg is developed. Based on the models proposed in the three steps, this thesis creates schedule design instances that involve almost all the major airports and markets in the United States. The instances of the frequency assignment model created in this thesis are large-scale non-convex mixed-integer programming problems, and this dissertation develops an overall network structure and proposes iterative algorithms for solving these instances. The instances of both the rough fleet assignment model and the timetable model created in this thesis are large-scale mixed-integer programming problems, and this dissertation develops subproblem schemes for solving these instances. Based on these solution algorithms, this dissertation also presents

  15. Aircraft Dynamic Modeling in Turbulence

    Science.gov (United States)

    Morelli, Eugene A.; Cunninham, Kevin

    2012-01-01

    A method for accurately identifying aircraft dynamic models in turbulence was developed and demonstrated. The method uses orthogonal optimized multisine excitation inputs and an analytic method for enhancing signal-to-noise ratio for dynamic modeling in turbulence. A turbulence metric was developed to accurately characterize the turbulence level using flight measurements. The modeling technique was demonstrated in simulation, then applied to a subscale twin-engine jet transport aircraft in flight. Comparisons of modeling results obtained in turbulent air to results obtained in smooth air were used to demonstrate the effectiveness of the approach.

  16. Versatile Electric Propulsion Aircraft Testbed Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An all-electric aircraft testbed is proposed to provide a dedicated development environment for the rigorous study and advancement of electrically powered aircraft....

  17. Modular Electric Propulsion Test Bed Aircraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An all electric aircraft test bed is proposed to provide a dedicated development environment for the rigorous study and advancement of electrically powered aircraft....

  18. Military Airlift: The Joint Cargo Aircraft Program

    National Research Council Canada - National Science Library

    Knight, William

    2007-01-01

    Joint Cargo Aircraft (JCA) is a joint acquisition program between the Army and the Air Force designed to procure a commercial off-the-shelf aircraft, capable of meeting Army requirements for "direct support" to maneuver units...

  19. Military Airlift: The Joint Cargo Aircraft Program

    National Research Council Canada - National Science Library

    Hess, Allan

    2008-01-01

    Joint Cargo Aircraft (JCA) is a joint acquisition program between the Army and Air Force intended to procure a commercial off-the-shelf aircraft capable of meeting Army and Air Force requirements for intra-theater airlift...

  20. Statistical estimation of aircraft service conditions

    Directory of Open Access Journals (Sweden)

    Боузаієнне Меккі бен Салем

    2005-03-01

    Full Text Available  The question of an estimation of aircraft service conditions in airlines with use of statistical methods is considered at the analysis of maintenance programs of a aircrafts park to normative requirements.

  1. Silent Aircraft Initiative Concept Risk Assessment

    Science.gov (United States)

    Nickol, Craig L.

    2008-01-01

    A risk assessment of the Silent Aircraft Initiative's SAX-40 concept design for extremely low noise has been performed. A NASA team developed a list of 27 risk items, and evaluated the level of risk for each item in terms of the likelihood that the risk would occur and the consequences of the occurrence. The following risk items were identified as high risk, meaning that the combination of likelihood and consequence put them into the top one-fourth of the risk matrix: structures and weight prediction; boundary-layer ingestion (BLI) and inlet design; variable-area exhaust and thrust vectoring; displaced-threshold and continuous descent approach (CDA) operational concepts; cost; human factors; and overall noise performance. Several advanced-technology baseline concepts were created to serve as a basis for comparison to the SAX-40 concept. These comparisons indicate that the SAX-40 would have significantly greater research, development, test, and engineering (RDT&E) and production costs than a conventional aircraft with similar technology levels. Therefore, the cost of obtaining the extremely low noise capability that has been estimated for the SAX-40 is significant. The SAX-40 concept design proved successful in focusing attention toward low noise technologies and in raising public awareness of the issue.

  2. THE AIRPORT DE-ICING OF AIRCRAFTS

    Directory of Open Access Journals (Sweden)

    Robert KONIECZKA

    2015-03-01

    Full Text Available This article provides a summary of the issues involved in de-icing several kinds of aircrafts before flight. The basic risks of an iced aircraft and the factors that can influence its intensity are stated. It discusses the methods for de-icing and protecting against ice formation on small aircrafts, helicopters, and large aircrafts. It also classifies the fluids and other methods used for these de-icing operations, and explains the characteristics and limitations of their use.

  3. Modeling aircraft noise induced sleep disturbance

    Science.gov (United States)

    McGuire, Sarah M.

    One of the primary impacts of aircraft noise on a community is its disruption of sleep. Aircraft noise increases the time to fall asleep, the number of awakenings, and decreases the amount of rapid eye movement and slow wave sleep. Understanding these changes in sleep may be important as they could increase the risk for developing next-day effects such as sleepiness and reduced performance and long-term health effects such as cardiovascular disease. There are models that have been developed to predict the effect of aircraft noise on sleep. However, most of these models only predict the percentage of the population that is awakened. Markov and nonlinear dynamic models have been developed to predict an individual's sleep structure during the night. However, both of these models have limitations. The Markov model only accounts for whether an aircraft event occurred not the noise level or other sound characteristics of the event that may affect the degree of disturbance. The nonlinear dynamic models were developed to describe normal sleep regulation and do not have a noise effects component. In addition, the nonlinear dynamic models have slow dynamics which make it difficult to predict short duration awakenings which occur both spontaneously and as a result of nighttime noise exposure. The purpose of this research was to examine these sleep structure models to determine how they could be altered to predict the effect of aircraft noise on sleep. Different approaches for adding a noise level dependence to the Markov Model was explored and the modified model was validated by comparing predictions to behavioral awakening data. In order to determine how to add faster dynamics to the nonlinear dynamic sleep models it was necessary to have a more detailed sleep stage classification than was available from visual scoring of sleep data. An automatic sleep stage classification algorithm was developed which extracts different features of polysomnography data including the

  4. FLIGHT DYNAMICS MODEL OF ONE CLASS OF AIRCRAFT WITH A VIEW OF ELASTIC CONSTRUCTION

    Directory of Open Access Journals (Sweden)

    2016-01-01

    Full Text Available It remains urgent problem of damping of elastic vibrations occurring aircraft structure means the automatic control systems on board. In solving this problem the aircraft elastic model is the basis for the synthesis of control laws and analysis of closed-loop system "control object - the regulator." In general, the problem of mathematical modeling of flight dynamics of the elastic aircraft breaks for at least another two objectives, one of which - direct simulation of the behavior of elastic aircraft defined interacting forces, and the other - the account of the changes operating aerogidrodynamic forces and moments caused by the deformation elastic aircraft and work control systems. This paper discusses the theoretical basis of the approach to the solution of this problem, based on the replacement of the actual design of aircraft by equivalent circuit and its implementation for the missiles, the most simple in terms of schematic, class of aircraft. At the same time accounting for changes in aerodynamic forces and moments caused by the elastic deformation of the aircraft, it was performed by help of stationary hypothesis

  5. Advanced aircraft service life monitoring method via flight-by-flight load spectra

    Science.gov (United States)

    Lee, Hongchul

    This research is an effort to understand current method and to propose an advanced method for Damage Tolerance Analysis (DTA) for the purpose of monitoring the aircraft service life. As one of tasks in the DTA, the current indirect Individual Aircraft Tracking (IAT) method for the F-16C/D Block 32 does not properly represent changes in flight usage severity affecting structural fatigue life. Therefore, an advanced aircraft service life monitoring method based on flight-by-flight load spectra is proposed and recommended for IAT program to track consumed fatigue life as an alternative to the current method which is based on the crack severity index (CSI) value. Damage Tolerance is one of aircraft design philosophies to ensure that aging aircrafts satisfy structural reliability in terms of fatigue failures throughout their service periods. IAT program, one of the most important tasks of DTA, is able to track potential structural crack growth at critical areas in the major airframe structural components of individual aircraft. The F-16C/D aircraft is equipped with a flight data recorder to monitor flight usage and provide the data to support structural load analysis. However, limited memory of flight data recorder allows user to monitor individual aircraft fatigue usage in terms of only the vertical inertia (NzW) data for calculating Crack Severity Index (CSI) value which defines the relative maneuver severity. Current IAT method for the F-16C/D Block 32 based on CSI value calculated from NzW is shown to be not accurate enough to monitor individual aircraft fatigue usage due to several problems. The proposed advanced aircraft service life monitoring method based on flight-by-flight load spectra is recommended as an improved method for the F-16C/D Block 32 aircraft. Flight-by-flight load spectra was generated from downloaded Crash Survival Flight Data Recorder (CSFDR) data by calculating loads for each time hack in selected flight data utilizing loads equations. From

  6. 14 CFR 47.33 - Aircraft not previously registered anywhere.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Aircraft not previously registered anywhere... TRANSPORTATION AIRCRAFT AIRCRAFT REGISTRATION Certificates of Aircraft Registration § 47.33 Aircraft not previously registered anywhere. (a) A person who is the owner of an aircraft that has not been registered...

  7. 14 CFR 91.117 - Aircraft speed.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aircraft speed. 91.117 Section 91.117... AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Flight Rules General § 91.117 Aircraft speed. (a) Unless otherwise authorized by the Administrator, no person may operate an aircraft below 10...

  8. 78 FR 67309 - Earth Stations Aboard Aircraft

    Science.gov (United States)

    2013-11-12

    ... COMMISSION 47 CFR Part 25 Earth Stations Aboard Aircraft AGENCY: Federal Communications Commission. ACTION... collection associated with the Commission's Earth Station Aboard Aircraft, Report and Order (Order), which adopted licensing and service rules for Earth Stations Aboard Aircraft (ESAA) communicating with Fixed...

  9. 48 CFR 908.7102 - Aircraft.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Aircraft. 908.7102 Section... REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special Items 908.7102 Aircraft. Acquisition of aircraft shall be in accordance with DOE-PMR 41 CFR 109-38.5205. ...

  10. 14 CFR 21.127 - Tests: aircraft.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Tests: aircraft. 21.127 Section 21.127 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Production Under Type Certificate Only § 21.127 Tests: aircraft. (a) Each...

  11. 14 CFR 34.6 - Aircraft safety.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Aircraft safety. 34.6 Section 34.6 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES General Provisions § 34.6 Aircraft...

  12. 14 CFR 135.125 - Aircraft security.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Aircraft security. 135.125 Section 135.125... AND ON DEMAND OPERATIONS AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Flight Operations § 135.125 Aircraft security. Certificate holders conducting operators conducting operations under this part...

  13. 14 CFR 91.209 - Aircraft lights.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aircraft lights. 91.209 Section 91.209... Requirements § 91.209 Aircraft lights. No person may: (a) During the period from sunset to sunrise (or, in... or the sun is more than 6 degrees below the horizon)— (1) Operate an aircraft unless it has lighted...

  14. 19 CFR 122.37 - Precleared aircraft.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Precleared aircraft. 122.37 Section 122.37 Customs... AIR COMMERCE REGULATIONS Landing Requirements § 122.37 Precleared aircraft. (a) Application. This section applies when aircraft carrying crew, passengers and baggage, or merchandise which has been...

  15. 36 CFR 13.1004 - Aircraft use.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Aircraft use. 13.1004 Section... § 13.1004 Aircraft use. In extraordinary cases where no reasonable alternative exists, local rural residents who permanently reside in the following exempted community(ies) may use aircraft for access to...

  16. 19 CFR 122.42 - Aircraft entry.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Aircraft entry. 122.42 Section 122.42 Customs... AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within...

  17. 31 CFR 560.528 - Aircraft safety.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Aircraft safety. 560.528 Section 560..., Authorizations and Statements of Licensing Policy § 560.528 Aircraft safety. Specific licenses may be issued on a... the safety of civil aviation and safe operation of U.S.-origin commercial passenger aircraft. ...

  18. 50 CFR 27.34 - Aircraft.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Aircraft. 27.34 Section 27.34 Wildlife and... WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: With Vehicles § 27.34 Aircraft. The unauthorized operation of aircraft, including sail planes, and hang gliders, at altitudes resulting in...

  19. 47 CFR 32.6113 - Aircraft expense.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Aircraft expense. 32.6113 Section 32.6113... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6113 Aircraft expense. (a) This account shall include such costs as aircraft fuel, flight crews, mechanics and ground crews...

  20. 43 CFR 423.41 - Aircraft.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Aircraft. 423.41 Section 423.41 Public... Aircraft. (a) You must comply with any applicable Federal, State, and local laws, and with any additional... this part 423, with respect to aircraft landings, takeoffs, and operation on or in the proximity of...

  1. 47 CFR 32.2113 - Aircraft.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Aircraft. 32.2113 Section 32.2113... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2113 Aircraft. This account shall include the original cost of aircraft and any associated equipment and furnishings installed...

  2. Impact analysis of composite aircraft structures

    Science.gov (United States)

    Pifko, Allan B.; Kushner, Alan S.

    1993-01-01

    The impact analysis of composite aircraft structures is discussed. Topics discussed include: background remarks on aircraft crashworthiness; comments on modeling strategies for crashworthiness simulation; initial study of simulation of progressive failure of an aircraft component constructed of composite material; and research direction in composite characterization for impact analysis.

  3. Unmanned Cargo Aircraft : From Anywhere to Everywhere

    NARCIS (Netherlands)

    Heerkens, Hans

    2017-01-01

    While unmanned aircraft have been in use for decades, their suitability for transporting cargo is only now slowly being recognised. The first prototypes of unmanned cargo aircraft (UCA) are currently being tested. There are two categories of UCA: short-distance aircraft for delivering packages and

  4. Analyses of Aircraft Responses to Atmospheric Turbulence

    NARCIS (Netherlands)

    Van Staveren, W.H.J.J.

    2003-01-01

    The response of aircraft to stochastic atmospheric turbulence plays an important role in aircraft-design (load calculations), Flight Control System (FCS) design and flight-simulation (handling qualities research and pilot training). In order to simulate these aircraft responses, an accurate

  5. Aircraft height estimation using 2-D radar

    CSIR Research Space (South Africa)

    Hakl, H

    2010-01-01

    Full Text Available A method to infer height information from an aircraft tracked with a single 2-D search radar is presented. The method assumes level flight in the target aircraft and a good estimate of the speed of the aircraft. The method yields good results...

  6. Aircraft System Design and Integration

    Directory of Open Access Journals (Sweden)

    D. P. Coldbeck

    2000-01-01

    Full Text Available In the 1980's the British aircraft industry changed its approach to the management of projects from a system where a project office would manage a project and rely on a series of specialist departments to support them to a more process oriented method, using systems engineering models, whose most outwardly visible signs were the introduction of multidisciplinary product teams. One of the problems with the old method was that the individual departments often had different priorities and projects would get uneven support. The change in the system was only made possible for complex designs by the electronic distribution of data giving instantaneous access to all involved in the project. In 1997 the Defence and Aerospace Foresight Panel emphasised the need for a system engineering approach if British industry was to remain competitive. The Royal Academy of Engineering recognised that the change in working practices also changed what was required of a chartered engineer and redefined their requirements in 1997 [1]. The result of this is that engineering degree courses are now judged against new criteria with more emphasis placed on the relevance to industry rather than on purely academic content. At the University of Glasgow it was realized that the students ought to be made aware of current working practices and that there ought to be a review to ensure that the degrees give students the skills required by industry. It was decided to produce a one week introduction course in systems engineering for Masters of Engineering (MEng students to be taught by both university lecturers and practitioners from a range of companies in the aerospace industry with the hope of expanding the course into a module. The reaction of the students was favourable in terms of the content but it seems ironic that the main criticism was that there was not enough discussion involving the students. This paper briefly describes the individual teaching modules and discusses the

  7. Aircraft Lightning Electromagnetic Environment Measurement

    Science.gov (United States)

    Ely, Jay J.; Nguyen, Truong X.; Szatkowski, George N.

    2011-01-01

    This paper outlines a NASA project plan for demonstrating a prototype lightning strike measurement system that is suitable for installation onto research aircraft that already operate in thunderstorms. This work builds upon past data from the NASA F106, FAA CV-580, and Transall C-180 flight projects, SAE ARP5412, and the European ILDAS Program. The primary focus is to capture airframe current waveforms during attachment, but may also consider pre and post-attachment current, electric field, and radiated field phenomena. New sensor technologies are being developed for this system, including a fiber-optic Faraday polarization sensor that measures lightning current waveforms from DC to over several Megahertz, and has dynamic range covering hundreds-of-volts to tens-of-thousands-of-volts. A study of the electromagnetic emission spectrum of lightning (including radio wave, microwave, optical, X-Rays and Gamma-Rays), and a compilation of aircraft transfer-function data (including composite aircraft) are included, to aid in the development of other new lightning environment sensors, their placement on-board research aircraft, and triggering of the onboard instrumentation system. The instrumentation system will leverage recent advances in high-speed, high dynamic range, deep memory data acquisition equipment, and fiber-optic interconnect.

  8. Promising Electric Aircraft Drive Systems

    Science.gov (United States)

    Dudley, Michael R.

    2010-01-01

    An overview of electric aircraft propulsion technology performance thresholds for key power system components is presented. A weight comparison of electric drive systems with equivalent total delivered energy is made to help identify component performance requirements, and promising research and development opportunities.

  9. Flight Control of Flexible Aircraft

    Science.gov (United States)

    Nguyen, Nhan T.

    2017-01-01

    This presentation presents an overview of flight control research for flexible high aspect wing aircraft in support of the NASA ARMD Advanced Air Transport Technology (AATT) project. It summarizes multi-objective flight control technology being developed for drag optimization, flutter suppression, and maneuver and gust load alleviation.

  10. Bonded repairs for aircraft fuselages

    OpenAIRE

    Vlot, A.; Verhoeven, S.; Nijssen, P.J.M.

    1998-01-01

    This report will give an overview of the bonded repair work that has been done over the last few years by the Faculty of Aerospace Engineering of Delft University of Technology, in cooperation with the Center for Aircraft Structural Life Extension at the United States Air Force Academy in Colorado Springs.

  11. Bonded repairs for aircraft fuselages

    NARCIS (Netherlands)

    Vlot, A.; Verhoeven, S.; Nijssen, P.J.M.

    1998-01-01

    This report will give an overview of the bonded repair work that has been done over the last few years by the Faculty of Aerospace Engineering of Delft University of Technology, in cooperation with the Center for Aircraft Structural Life Extension at the United States Air Force Academy in Colorado

  12. MATE. Multi Aircraft Training Environment

    DEFF Research Database (Denmark)

    Hauland, G.; Bove, T.; Andersen, Henning Boje

    2002-01-01

    A medium fidelity and low cost training device for pilots, called the Multi Aircraft Training Environment (MATE), is developed to replace other low fidelity stand-alone training devices and integrate them into a flexible environment, primarily aimed attraining pilots in checklist procedures...

  13. Aircraft Fuel Cell Power Systems

    Science.gov (United States)

    Needham, Robert

    2004-01-01

    In recent years, fuel cells have been explored for use in aircraft. While the weight and size of fuel cells allows only the smallest of aircraft to use fuel cells for their primary engines, fuel cells have showed promise for use as auxiliary power units (APUs), which power aircraft accessories and serve as an electrical backup in case of an engine failure. Fuel cell MUS are both more efficient and emit fewer pollutants. However, sea-level fuel cells need modifications to be properly used in aircraft applications. At high altitudes, the ambient air has a much lower pressure than at sea level, which makes it much more difficult to get air into the fuel cell to react and produce electricity. Compressors can be used to pressurize the air, but this leads to added weight, volume, and power usage, all of which are undesirable things. Another problem is that fuel cells require hydrogen to create electricity, and ever since the Hindenburg burst into flames, aircraft carrying large quantities of hydrogen have not been in high demand. However, jet fuel is a hydrocarbon, so it is possible to reform it into hydrogen. Since jet fuel is already used to power conventional APUs, it is very convenient to use this to generate the hydrogen for fuel-cell-based APUs. Fuel cells also tend to get large and heavy when used for applications that require a large amount of power. Reducing the size and weight becomes especially beneficial when it comes to fuel cells for aircraft. My goal this summer is to work on several aspects of Aircraft Fuel Cell Power System project. My first goal is to perform checks on a newly built injector rig designed to test different catalysts to determine the best setup for reforming Jet-A fuel into hydrogen. These checks include testing various thermocouples, transmitters, and transducers, as well making sure that the rig was actually built to the design specifications. These checks will help to ensure that the rig will operate properly and give correct results

  14. Analysis of a Stretched Derivative Aircraft with Open Rotor Propulsion

    Science.gov (United States)

    Berton, Jeffrey J.; Hendricks, Eric S.; Haller, William J.; Guynn, Mark D.

    2015-01-01

    Research into advanced, high-speed civil turboprops received significant attention during the 1970s and 1980s when fuel efficiency was the driving focus of U.S. aeronautical research. But when fuel prices declined sharply there was no longer sufficient motivation to continue maturing the technology. Recent volatility in fuel prices and increasing concern for aviation's environmental impact, however, have renewed interest in unducted, open rotor propulsion and revived research by NASA and a number of engine manufacturers. Recently, NASA and General Electric have teamed to conduct several investigations into the performance and noise of an advanced, single-aisle transport with open rotor propulsion. The results of these initial studies indicate open rotor engines have the potential to provide significant reduction in fuel consumption compared to aircraft using turbofan engines with equivalent core technology. In addition, noise analysis of the concept indicates that an open rotor aircraft in the single-aisle transport class would be able to meet current noise regulations with margin. The behavior of derivative open rotor transports is of interest. Heavier, "stretched" derivative aircraft tend to be noisier than their lighter relatives. Of particular importance to the business case for the concept is how the noise margin changes relative to regulatory limits within a family of similar open rotor aircraft. The subject of this report is a performance and noise assessment of a notional, heavier, stretched derivative airplane equipped with throttle-push variants of NASA's initial open rotor engine design.

  15. Number and mass analysis of particles emitted by aircraft engine

    Directory of Open Access Journals (Sweden)

    Jasiński Remigiusz

    2017-01-01

    Full Text Available Exhaust emissions from aircraft is a complex issue because of the limited possibility of measurements in flight conditions. Most of the studies on this subject were performed on the basis of stationary test. Engine certification data is used to calculate total emissions generated by air transport. However, it doesnt provide any information about the local effects of air traffic. The main threat to local communities is particulate matter emissions, which adversely affects human health. Emissions from air transport affect air quality, particularly in the vicinity of the airports; it also contributes to the greenhouse effect. The article presents the measurement results of the concentration and size distribution of particles emitted during aircraft landing operation. Measurements were carried out during the landings of aircraft at a civilian airport. It was found that a single landing operation causes particle number concentration value increase of several ten-fold in a short period of time. Using aircraft engine certification data, the methodology for determination of the total number of particles emitted during a single landing operation was introduced.

  16. Health and usage monitoring system for the small aircraft composite structure

    Science.gov (United States)

    Růžička, Milan; Dvořák, Milan; Schmidová, Nikola; Šašek, Ladislav; Štěpánek, Martin

    2017-07-01

    This paper is focused on the design of the health and usage monitoring system (HUMS) of the composite ultra-light aircrafts. A multichannel measuring system was developed and installed for recording of the long-term operational measurements of the UL airplane. Many fiber Bragg grating sensors were implemented into the composite aircraft structure, mainly in the glue joints. More than ten other analog functions and signals of the aircraft is monitored and can be correlated together. Changing of the FBG sensors responses in monitored places and their correlations, comparing with the calibration and recalibration procedures during a monitored life may indicate damage (eg. in bonded joints) and complements the HUMS system.

  17. Effects of activity interference on annoyance due to aircraft noise

    Science.gov (United States)

    Willshire, K. F.; Powell, C. A.

    1981-01-01

    The effects of aircraft flyover noise on annoyance were compared for face to face conversation, reverie, and television viewing. Eighteen 5 minute sessions, each composed of three flyovers, were presented on each of 2 days to subjects in a simulated living room. Twelve pairs of females and 12 pairs of males were tested, once before and once after work. Flyovers varied in peak noise level from 53 to 83 dB, A weighted. On each day, subjects engaged in 18 sessions, six of conversation, six of television viewing, and six of reverie. The subjects completed subjective ratings of annoyance and acceptability following every session. Annoyance and unacceptability rating scores were significantly higher for the activity of television viewing compared to conversation or reverie. There was no difference between judgments during the latter two activities. No differences were found in the judgments when compared on the basis of "fatigue" (before/after work) or sex of the subject.

  18. Perspectives on Highly Adaptive or Morphing Aircraft

    Science.gov (United States)

    McGowan, Anna-Maria R.; Vicroy, Dan D.; Busan, Ronald C.; Hahn, Andrew S.

    2009-01-01

    The ability to adapt to different flight conditions has been fundamental to aircraft design since the Wright Brothers first flight. Over a hundred years later, unconventional aircraft adaptability, often called aircraft morphing has become a topic of considerable renewed interest. In the past two decades, this interest has been largely fuelled by advancements in multi-functional or smart materials and structures. However, highly adaptive or morphing aircraft is certainly a cross-discipline challenge that stimulates a wide range of design possibilities. This paper will review some of the history of morphing aircraft including recent research programs and discuss some perspectives on this work.

  19. Hydrogen Storage for Aircraft Applications Overview

    Science.gov (United States)

    Colozza, Anthony J.; Kohout, Lisa (Technical Monitor)

    2002-01-01

    Advances in fuel cell technology have brought about their consideration as sources of power for aircraft. This power can be utilized to run aircraft systems or even provide propulsion power. One of the key obstacles to utilizing fuel cells on aircraft is the storage of hydrogen. An overview of the potential methods of hydrogen storage was compiled. This overview identifies various methods of hydrogen storage and points out their advantages and disadvantages relative to aircraft applications. Minimizing weight and volume are the key aspects to storing hydrogen within an aircraft. An analysis was performed to show how changes in certain parameters of a given storage system affect its mass and volume.

  20. Propeller aircraft noise legislation—A comprehensive review

    Science.gov (United States)

    Heller, Hanno H.

    After a brief historical review of the development of propeller aircraft noise certification by the International Civil Aviation Organization (ICAO), this paper describes in detail the pertinent ICAO-document-the ‘ANNEX 16’-which contains ‘Standards and Recommended Practices’ for the noise certification of propeller-driven aeorplanes either above, or not exceeding, a certificated take-off mass of 5700 kg. Direct experience in the ‘day to day’ practice of conducting aircraft flyover noise measurements for purposes of noise certification is revealed, potential pit-falls, ‘loop-holes’, and present uncertainties in the various procedures are described, and the efforts of the ICAO-Committee on Aircraft Noise (CAN), and its successor organization, the ICAO-Committee on Aviation Environmental Protection (CAEP) to resolve ensuing problems, are given extensive space. The continuing development, as well as the frequently necessary consolidations, of noise certification methods and procedures requires substantial research effort, both in terms of actual dedicated flight testing and wind tunnel testing. This work is dealt with in fair detail and where necessary explained with illustrations, often directly out of research reports. This should give the reader an impression of the enormous complexity of noise certificating propeller aircraft, which after all entails not only legislative aspects, but also basic and applied aerocoustic research. However, in addition to discussing the current state of propeller-aeroplane noise certification, there are sections which go back in time to elaborate on the thoughts and the sometimes dead-end streets which were penetrated in the numerous attempts to improve noise certification. Other sections still look into the future to present changes in propeller aircraft noise legislation that are expected to be agreed upon either in the near- or medium-term.

  1. New possibilities of using A-319CJ aircraft at the Czech Air Force

    OpenAIRE

    Miroslav JANOŠEK

    2011-01-01

    The article analyses remarkable changes in activities of the transport airbase in terms of substitution of obsolete aircraft by modern transport airplanes. Further, differences between transport airbase’s aircraft and Czech Airlines’ airplanes are introduced, as well as fundamental tactical and operating specifications, time and space factors regarding personnel transport, supplies transport and possibilities of Airbus A319CJ’s freight hold adjustment in dependence on the nature of transport....

  2. A study of external fuel vaporization. [for aircraft gas turbine engines

    Science.gov (United States)

    Szetela, E. J.; Chiappetta, L.; Baker, C. E.

    1981-01-01

    Candidate external vaporizer designs for an aircraft gas turbine engine are evaluated with respect to fuel thermal stability, integration of the vaporizer system into the aircraft engine, engine and vaporizer dynamic response, startup and altitude restart, engine performance, control requirements, safety, and maintenance. The selected concept is shown to offer potential gains in engine performance in terms of reduced specific fuel consumption and improved engine thrust/weight ratio. The thrust/weight improvement can be traded against vaporization system weight.

  3. New possibilities of using A-319CJ aircraft at the Czech Air Force

    Directory of Open Access Journals (Sweden)

    Miroslav JANOŠEK

    2011-01-01

    Full Text Available The article analyses remarkable changes in activities of the transport airbase in terms of substitution of obsolete aircraft by modern transport airplanes. Further, differences between transport airbase’s aircraft and Czech Airlines’ airplanes are introduced, as well as fundamental tactical and operating specifications, time and space factors regarding personnel transport, supplies transport and possibilities of Airbus A319CJ’s freight hold adjustment in dependence on the nature of transport.

  4. Aircraft Survivability: An Overview of Aircraft Fire Protection, Spring 2008

    Science.gov (United States)

    2008-01-01

    combination of the two. The detectors are designed to look at a narrow frequency band; however, initial designs were not sophis- ticated enough to...for complete ignition prevention. Experimental Setup This test program was conducted at the Simulated Aircraft Fuel Tank Environ- ment ( SAFTE ) Facility...experi- enced a roll oscillation at a frequency of 0.35 hertz (Hz). Figure 3 shows a liquid phenomenon known as a hydraulic jump (circled region

  5. Ames T-3 fire test facility - Aircraft crash fire simulation

    Science.gov (United States)

    Fish, R. H.

    1976-01-01

    There is a need to characterize the thermal response of materials exposed to aircraft fuel fires. Large scale open fire tests are costly and pollute the local environment. This paper describes the construction and operation of a subscale fire test that simulates the heat flux levels and thermochemistry of typical open pool fires. It has been termed the Ames T-3 Test and has been used extensively by NASA since 1969 to observe the behavior of materials exposed to JP-4 fuel fires.

  6. Quasi-Static Viscoelasticity Loading Measurements of an Aircraft Tire

    Science.gov (United States)

    Mason, Angela J.; Tanner, John A.; Johnson, Arthur R.

    1997-01-01

    Stair-step loading, cyclic loading, and long-term relaxation tests were performed on an aircraft tire to observe the quasi-static viscoelastic response of the tire. The data indicate that the tire continues to respond viscoelastically even after it has been softened by deformation. Load relaxation data from the stair-step test at the 15,000-lb loading was fit to a monotonically decreasing Prony series.

  7. Friction, Freeplay and Flutter of Manually Controlled Aircraft

    OpenAIRE

    Eller, David

    2007-01-01

    The effect of nonlinear friction and freeplay in the control system on flut- ter is investigated for the case of light aircraft with manually operated control surfaces. A standard linear modal subspace model of the aeroelastic system is extended with nonlinear terms, so that time-domain simulations can be per- formed. Furthermore, the harmonic balance method is employed to obtain a frequency-domain formulation, which allows a convenient, though approxi- mate, computation of the stability boun...

  8. MANPADS protection for civil aircraft using an expendable decoy

    Science.gov (United States)

    Walmsley, Roy H.; Friede, Johan; Millwood, Nicolas; Butters, Brian

    2009-09-01

    With the ever present threat of MANPADS throughout the world the protection of civil aircraft is a desirable capability that has special requirements in terms of certification, safety, logistics, affordability, environmental impact and exportability. The Civil Aircraft Missile Protection System (CAMPS), which includes the CIV-IR (infrared) leaf-based pyrophoric (not pyrotechnic) expendable countermeasure, is a system designed to meet these requirements. This paper presents the operating aspects of the decoy, including discussion of design features necessary to ensure safety both on the ground and in flight and assure successful deployment. The characteristics of the CIV-IR have been measured, both on static single leaves in the laboratory and on deployed packs in field tests and aircraft trials. These measured properties have been used in engagement modelling and simulation to assess the level of protection that can be afforded to commercial airliners against generation 1 and 2 MANPADS threats. Aircraft flight trials with ground based seekers have also been carried out to validate the modelling work. These combine to define the deployment patterns necessary for a successful seduction of the MANPAD.

  9. An Algorithm for Managing Aircraft Movement on an Airport Surface

    Directory of Open Access Journals (Sweden)

    Giuseppe Maresca

    2013-08-01

    Full Text Available The present paper focuses on the development of an algorithm for safely and optimally managing the routing of aircraft on an airport surface in future airport operations. This tool is intended to support air traffic controllers’ decision-making in selecting the paths of all aircraft and the engine startup approval time for departing ones. Optimal routes are sought for minimizing the time both arriving and departing aircraft spend on an airport surface with engines on, with benefits in terms of safety, efficiency and costs. The proposed algorithm first computes a standalone, shortest path solution from runway to apron or vice versa, depending on the aircraft being inbound or outbound, respectively. For taking into account the constraints due to other traffic on an airport surface, this solution is amended by a conflict detection and resolution task that attempts to reduce and possibly nullify the number of conflicts generated in the first phase. An example application on a simple Italian airport exemplifies how the algorithm can be applied to true-world applications. Emphasis is given on how to model an airport surface as a weighted and directed graph with non-negative weights, as required for the input to the algorithm.

  10. Wind tunnel technology for the development of future commercial aircraft

    Science.gov (United States)

    Szodruch, J.

    1986-01-01

    Requirements for new technologies in the area of civil aircraft design are mainly related to the high cost involved in the purchase of modern, fuel saving aircraft. A second important factor is the long term rise in the price of fuel. The demonstration of the benefits of new technologies, as far as these are related to aerodynamics, will,for the foreseeable future, still be based on wind tunnel measurements. Theoretical computation methods are very successfully used in design work, wing optimization, and an estimation of the Reynolds number effect. However, wind tunnel tests are still needed to verify the feasibility of the considered concepts. Along with other costs, the cost for the wind tunnel tests needed for the development of an aircraft is steadily increasing. The present investigation is concerned with the effect of numerical aerodynamics and civil aircraft technology on the development of wind tunnels. Attention is given to the requirements for the wind tunnel, investigative methods, measurement technology, models, and the relation between wind tunnel experiments and theoretical methods.

  11. An investigation of fighter aircraft agility

    Science.gov (United States)

    Valasek, John; Downing, David R.

    1993-01-01

    This report attempts to unify in a single document the results of a series of studies on fighter aircraft agility funded by the NASA Ames Research Center, Dryden Flight Research Facility and conducted at the University of Kansas Flight Research Laboratory during the period January 1989 through December 1993. New metrics proposed by pilots and the research community to assess fighter aircraft agility are collected and analyzed. The report develops a framework for understanding the context into which the various proposed fighter agility metrics fit in terms of application and testing. Since new metrics continue to be proposed, this report does not claim to contain every proposed fighter agility metric. Flight test procedures, test constraints, and related criteria are developed. Instrumentation required to quantify agility via flight test is considered, as is the sensitivity of the candidate metrics to deviations from nominal pilot command inputs, which is studied in detail. Instead of supplying specific, detailed conclusions about the relevance or utility of one candidate metric versus another, the authors have attempted to provide sufficient data and analyses for readers to formulate their own conclusions. Readers are therefore ultimately responsible for judging exactly which metrics are 'best' for their particular needs. Additionally, it is not the intent of the authors to suggest combat tactics or other actual operational uses of the results and data in this report. This has been left up to the user community. Twenty of the candidate agility metrics were selected for evaluation with high fidelity, nonlinear, non real-time flight simulation computer programs of the F-5A Freedom Fighter, F-16A Fighting Falcon, F-18A Hornet, and X-29A. The information and data presented on the 20 candidate metrics which were evaluated will assist interested readers in conducting their own extensive investigations. The report provides a definition and analysis of each metric; details

  12. Science of the subjective.

    Science.gov (United States)

    Jahn, R G; Dunne, B J

    2007-01-01

    Over the greater portion of its long scholarly history, the particular form of human observation, reasoning, and technical deployment we properly term "science" has relied at least as much on subjective experience and inspiration as it has on objective experiments and theories. Only over the past few centuries has subjectivity been progressively excluded from the practice of science, leaving an essentially secular analytical paradigm. Quite recently, however, a compounding constellation of newly inexplicable physical evidence, coupled with a growing scholarly interest in the nature and capability of human consciousness, are beginning to suggest that this sterilization of science may have been excessive and could ultimately limit its epistemological reach and cultural relevance. In particular, an array of demonstrable consciousness-related anomalous physical phenomena, a persistent pattern of biological and medical anomalies, systematic studies of mind/brain relationships and the mechanics of human creativity, and a burgeoning catalogue of human factors effects within contemporary information processing technologies, all display empirical correlations with subjective aspects that greatly complicate, and in many cases preclude, their comprehension on strictly objective grounds. However, any disciplined re-admission of subjective elements into rigorous scientific methodology will hinge on the precision with which they can be defined, measured, and represented, and on the resilience of established scientific techniques to their inclusion. For example, any neo-subjective science, while retaining the logical rigor, empirical/theoretical dialogue, and cultural purpose of its rigidly objective predecessor, would have the following requirements: acknowledgment of a proactive role for human consciousness; more explicit and profound use of interdisciplinary metaphors; more generous interpretations of measurability, replicability, and resonance; a reduction of ontological

  13. CID Aircraft slap-down

    Science.gov (United States)

    1984-01-01

    In this photograph the B-720 is seen during the moments of initial impact. The left wing is digging into the lakebed while the aircraft continues sliding towards wing openers. In 1984 NASA Dryden Flight Research Facility and the Federal Aviation Administration (FAA) teamed-up in a unique flight experiment called the Controlled Impact Demonstration (CID). The test involved crashing a Boeing 720 aircraft with four JT3C-7 engines burning a mixture of standard fuel with an additive, Anti-misting Kerosene (AMK), designed to supress fire. In a typical aircraft crash, fuel spilled from ruptured fuel tanks forms a fine mist that can be ignited by a number of sources at the crash site. In 1984 the NASA Dryden Flight Research Facility (after 1994 a full-fledged Center again) and the Federal Aviation Administration (FAA) teamed-up in a unique flight experiment called the Controlled Impact Demonstration (CID), to test crash a Boeing 720 aircraft using standard fuel with an additive designed to supress fire. The additive, FM-9, a high-molecular-weight long-chain polymer, when blended with Jet-A fuel had demonstrated the capability to inhibit ignition and flame propagation of the released fuel in simulated crash tests. This anti-misting kerosene (AMK) cannot be introduced directly into a gas turbine engine due to several possible problems such as clogging of filters. The AMK must be restored to almost Jet-A before being introduced into the engine for burning. This restoration is called 'degradation' and was accomplished on the B-720 using a device called a 'degrader.' Each of the four Pratt & Whitney JT3C-7 engines had a 'degrader' built and installed by General Electric (GE) to break down and return the AMK to near Jet-A quality. In addition to the AMK research the NASA Langley Research Center was involved in a structural loads measurement experiment, which included having instrumented dummies filling the seats in the passenger compartment. Before the final flight on December 1

  14. The Cognitive Challenges of Flying a Remotely Piloted Aircraft

    Science.gov (United States)

    Hobbs, Alan; Cardoza, Colleen; Null, Cynthia

    2016-01-01

    A large variety of Remotely Piloted Aircraft (RPA) designs are currently in production or in development. These aircraft range from small electric quadcopters that are flown close to the ground within visual range of the operator, to larger systems capable of extended flight in airspace shared with conventional aircraft. Before RPA can operate routinely and safely in civilian airspace, we need to understand the unique human factors associated with these aircraft. The task of flying an RPA in civilian airspace involves challenges common to the operation of other highly-automated systems, but also introduces new considerations for pilot perception, decision-making, and action execution. RPA pilots participated in focus groups where they were asked to recall critical incidents that either presented a threat to safety, or highlighted a case where the pilot contributed to system resilience or mission success. Ninety incidents were gathered from focus-groups. Human factor issues included the impact of reduced sensory cues, traffic separation in the absence of an out-the-window view, control latencies, vigilance during monotonous and ultra-long endurance flights, control station design considerations, transfer of control between control stations, the management of lost link procedures, and decision-making during emergencies. Some of these concerns have received significant attention in the literature, or are analogous to human factors of manned aircraft. The presentation will focus on issues that are poorly understood, and have not yet been the subject of extensive human factors study. Although many of the reported incidents were related to pilot error, the participants also provided examples of the positive contribution that humans make to the operation of highly-automated systems.

  15. Aircraft Derived Data Validation Algorithms

    Science.gov (United States)

    2012-08-06

    required to solve for wind. However, local variations in wind results in unrepresentative estimates when only two samples are used; Therefore, a more...CONCLUSION 37 10. FUTURE WORK 39 REFERENCES 40 A. DATA DEPENDENCY CHART A-1 B. WIND FIELD SAMPLE B-1 C. AIRCRAFT SPECIFIC VALIDATION REPORT (ASVR) SAMPLE ...C-1 D. CROSS TRACK REPORT (XTR) SAMPLE D-1 E. ACRONYM LIST E-1 viii LIST OF ILLUSTRATIONS Figure No. Page 1.1 Register Layouts 2 2.1 ATCRBS

  16. Piloted Aircraft Environment Simulation Techniques

    Science.gov (United States)

    1978-04-01

    model of the KC- 135 tanker aircraft. 1.2 AS INE EIEET DEFINEDI1T AS TNEAllRFORCE APRVED IT AS TESYSTEMS CNINA AS ThECONTRACTRMADE I AS N LOGISTCS ...approach trajectory, he will control speed with pitch attitude, and sink rate with power. More rapid changes can be achieved by reversing the control...thrust reversers (or parachutes) may be of most concern, coupled with runway conditions (water or ice) and crosswinds. Failures and assymetrics will

  17. Aircraft Evaluation Using Stochastic Duels

    Science.gov (United States)

    2017-09-01

    control , structural load factors, and weapon effectiveness are influential in determining the winner in the dogfight. Our model is designed to...models focus on higher resolution applications such as missile control designs. Our aim in this chapter is to provide a review of some of the...occurs. 1. The weapons onboard the aircraft are only missiles, thus excluding the use of guns . This assumption serves to focus on the more

  18. IAR-93 military aircraft monument

    Directory of Open Access Journals (Sweden)

    Radu BISCA

    2011-09-01

    Full Text Available In this presentation, we will concentrate on the vertical support, which is free from all sides. A Finite Element Model (FEM of the IAR-93 aircraft monument has been developed in PATRAN/NASTRAN®, partly from a previous ANSYS® model FEM can be used to investigate potential structural modifications or changes in column monument with realistic component corrections. Model validation should be part of every modern engineering analysis and quality assurance procedure

  19. Preparing aircraft propulsion for a new era in energy and the environment

    Science.gov (United States)

    Stewart, W. L.; Nored, D. L.; Grobman, J. S.; Feiler, C. E.; Petrash, D. A.

    1980-01-01

    Improving fuel efficiency, new sources of jet fuel, and noise and emission control are subjects of NASA's aeronautics program. Projects aimed at attaining a 5% fuel savings for existing engines and a 13-22% savings for the next generation of turbofan engines using advanced components, and establishing a basis for turboprop-powered commercial air transports with 30-40% savings over conventional turbofan aircraft at comparable speeds and altitudes, are discussed. Fuel sources are considered in terms of reduced hydrogen and higher aromatic contents and resultant higher liner temperatures, and attention is given to lean burning, improved fuel atomization, higher freezing-point fuel, and deriving jet fuel from shale oil or coal. Noise sources including the fan, turbine, combustion process, and flow over internal struts, and attenuation using acoustic treatment, are discussed, while near-term reduction of polluting gaseous emissions at both low and high power, and far-term defining of the minimum gaseous-pollutant levels possible from turbine engines are also under study.

  20. Impact of Airspace Charges on Transatlantic Aircraft Trajectories

    Science.gov (United States)

    Sridhar, Banavar; Ng, Hok K.; Linke, Florian; Chen, Neil Y.

    2015-01-01

    Aircraft flying over the airspace of different countries are subject to over-flight charges. These charges vary from country to country. Airspace charges, while necessary to support the communication, navigation and surveillance services, may lead to aircraft flying routes longer than wind-optimal routes and produce additional carbon dioxide and other gaseous emissions. This paper develops an optimal route between city pairs by modifying the cost function to include an airspace cost whenever an aircraft flies through a controlled airspace without landing or departing from that airspace. It is assumed that the aircraft will fly the trajectory at a constant cruise altitude and constant speed. The computationally efficient optimal trajectory is derived by solving a non-linear optimal control problem. The operational strategies investigated in this study for minimizing aircraft fuel burn and emissions include flying fuel-optimal routes and flying cost-optimal routes that may completely or partially reduce airspace charges en route. The results in this paper use traffic data for transatlantic flights during July 2012. The mean daily savings in over-flight charges, fuel cost and total operation cost during the period are 17.6 percent, 1.6 percent, and 2.4 percent respectively, along the cost- optimal trajectories. The transatlantic flights can potentially save $600,000 in fuel cost plus $360,000 in over-flight charges daily by flying the cost-optimal trajectories. In addition, the aircraft emissions can be potentially reduced by 2,070 metric tons each day. The airport pairs and airspace regions that have the highest potential impacts due to airspace charges are identified for possible reduction of fuel burn and aircraft emissions for the transatlantic flights. The results in the paper show that the impact of the variation in fuel price on the optimal routes is to reduce the difference between wind-optimal and cost-optimal routes as the fuel price increases. The

  1. Finite Element Analysis of Composite Aircraft Fuselage Frame

    Science.gov (United States)

    Dandekar, Aditya Milind

    Composites have been introduced in aircraft industries, for their stronger, stiffer, and lighter properties than their metal-alloys counterparts. The general purpose of an aircraft is to transport commercial or military payload. Aircraft frames primarily maintains the shape of fuselage and prevent instability of the structure. Fuselage is similar as wing in construction which consist of longitudinal elements (longerons and stringers), transverse elements (frames and bulkheads) and its external skin. The fuselage is subjected to forces such as the wing reactions, landing gear reaction, empennage reaction, inertia forces subjected due to size and weight, internal pressure forces due to high altitude. Frames also ensure fail-safe design against skin crack propagation due to hoops stress. Ideal fuselage frames cross section is often circular ring shape with a frame cap of Z section. They are mainly made up of light alloy commonly used is aluminium alloys such as Al-2024, Al-7010, Al-7050, Al-7175. Aluminium alloys have good strength to density ratios in compression and bending of thin plate. A high strength to weight ratio of composite materials can result in a lighter aircraft structure or better safety factor. This research focuses on analysis of fuselage frame under dynamic load condition with change in material. Composites like carbon fibre reinforced plastics [CFRP] and glass fibre reinforced plastics [GFRP] are compared with traditional aluminium alloy Al-7075. The frame is subjected to impact test by dropping it at a velocity of 30 ft. / secs from a height of 86 inch from its centre of gravity. These parameters are considered in event of failure of landing gear, and an aircraft is subject to belly landing or gear-up landing. The shear flow is calculated due to impact force which acts in radial direction. The frame is analysed under static structural and explicit dynamic load conditions. Geometry is created in ANSYS Design Modeler. Analysis setup is created using

  2. Quantification of advanced turboprop aircraft flyover noise annoyance

    Science.gov (United States)

    Mccurdy, D. A.

    1984-01-01

    A laboratory experiment was conducted to quantify the annoyance to advanced turboprop (propfan) aircraft flyover noise. A computer synthesis system was used to generate 45 realistic, time varying simulations of propeller aircraft flyover noise in which the tonal content was systematically varied to represent the factorial combinations of five fundamental frequencies, three frequency envelope shapes, and three tone-to-broadband noise ratios. In the experiment, 64 subjects judged the annoyance of recordings of the 45 synthesized flyover noises presented at three sound levels in a test facility which simulates the outdoor acoustic environment. Analyses of the judgements showed that frequency envelope shape did not significantly affect annoyance. The interaction of fundamental frequency with tone-to-broadband noise ratio did have a large and complex effect on annoyance. Duration corrected A-weighted sound pressure level with a modified tone correction predicted annoyance better than any other measurement procedure.

  3. Optimization of the vertical flight profile on the flight management system for green aircraft

    Science.gov (United States)

    Felix Patron, Roberto Salvador

    To reduce aircraft's fuel consumption, a new method to calculate flight trajectories to be implemented in commercial Flight Management Systems has been developed. The aircraft's model was obtained from a flight performance database, which included experimental flight data. The optimized trajectories for three different commercial aircraft have been analyzed and developed in this thesis. To obtain the optimal flight trajectory that reduces the global flight cost, the vertical and the LNAV profiles have been studied and analyzed to find the aircraft's available speeds, possible flight altitudes and alternative horizontal trajectories that could reduce the global fuel consumption. A dynamic weather model has been implemented to improve the precision of the algorithm. This weather model calculates the speed and direction of wind, and the outside air temperature from a public weather database. To reduce the calculation time, different time-optimization algorithms have been implemented, such as the Golden Section search method, and different types of genetic algorithms. The optimization algorithm calculates the aircraft trajectory considering the departure and arrival airport coordinates, the aircraft parameters, the in-flight restrictions such as speeds, altitudes and WPs. The final output is given in terms of the flight time, fuel consumption and global flight cost of the complete flight. To validate the optimization algorithm results, the software FlightSIM RTM has been used. This software considers a complete aircraft aerodynamic model for its simulations, giving results that are accurate and very close to reality.

  4. Creating a Test-Validated Finite-Element Model of the X-56A Aircraft Structure

    Science.gov (United States)

    Pak, Chan-Gi; Truong, Samson

    2014-01-01

    Small modeling errors in a finite-element model will eventually induce errors in the structural flexibility and mass, thus propagating into unpredictable errors in the unsteady aerodynamics and the control law design. One of the primary objectives of the X-56A Multi-Utility Technology Testbed aircraft is the flight demonstration of active flutter suppression and, therefore, in this study, the identification of the primary and secondary modes for the structural model tuning based on the flutter analysis of the X-56A aircraft. The ground-vibration test-validated structural dynamic finite-element model of the X-56A aircraft is created in this study. The structural dynamic finite-element model of the X-56A aircraft is improved using a model-tuning tool. In this study, two different weight configurations of the X-56A aircraft have been improved in a single optimization run. Frequency and the cross-orthogonality (mode shape) matrix were the primary focus for improvement, whereas other properties such as c.g. location, total weight, and off-diagonal terms of the mass orthogonality matrix were used as constraints. The end result was an improved structural dynamic finite-element model configuration for the X-56A aircraft. Improved frequencies and mode shapes in this study increased average flutter speeds of the X-56A aircraft by 7.6% compared to the baseline model.

  5. Creating a Test Validated Structural Dynamic Finite Element Model of the X-56A Aircraft

    Science.gov (United States)

    Pak, Chan-Gi; Truong, Samson

    2014-01-01

    Small modeling errors in the finite element model will eventually induce errors in the structural flexibility and mass, thus propagating into unpredictable errors in the unsteady aerodynamics and the control law design. One of the primary objectives of the Multi Utility Technology Test-bed, X-56A aircraft, is the flight demonstration of active flutter suppression, and therefore in this study, the identification of the primary and secondary modes for the structural model tuning based on the flutter analysis of the X-56A aircraft. The ground vibration test-validated structural dynamic finite element model of the X-56A aircraft is created in this study. The structural dynamic finite element model of the X-56A aircraft is improved using a model tuning tool. In this study, two different weight configurations of the X-56A aircraft have been improved in a single optimization run. Frequency and the cross-orthogonality (mode shape) matrix were the primary focus for improvement, while other properties such as center of gravity location, total weight, and offdiagonal terms of the mass orthogonality matrix were used as constraints. The end result was a more improved and desirable structural dynamic finite element model configuration for the X-56A aircraft. Improved frequencies and mode shapes in this study increased average flutter speeds of the X-56A aircraft by 7.6% compared to the baseline model.

  6. 14 CFR 91.111 - Operating near other aircraft.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Operating near other aircraft. 91.111... § 91.111 Operating near other aircraft. (a) No person may operate an aircraft so close to another aircraft as to create a collision hazard. (b) No person may operate an aircraft in formation flight except...

  7. 32 CFR 855.15 - Detaining an aircraft.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Detaining an aircraft. 855.15 Section 855.15 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS Civil Aircraft Landing Permits § 855.15 Detaining an aircraft...

  8. 47 CFR 87.191 - Foreign aircraft stations.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Foreign aircraft stations. 87.191 Section 87... AVIATION SERVICES Aircraft Stations § 87.191 Foreign aircraft stations. (a) Aircraft of member States of... States airspace only if a license has been issued by the State in which the aircraft is registered and...

  9. Using virtual reality technology for aircraft visual inspection training: presence and comparison studies.

    Science.gov (United States)

    Vora, Jeenal; Nair, Santosh; Gramopadhye, Anand K; Duchowski, Andrew T; Melloy, Brian J; Kanki, Barbara

    2002-11-01

    The aircraft maintenance industry is a complex system consisting of several interrelated human and machine components. Recognizing this, the Federal Aviation Administration (FAA) has pursued human factors related research. In the maintenance arena the research has focused on the aircraft inspection process and the aircraft inspector. Training has been identified as the primary intervention strategy to improve the quality and reliability of aircraft inspection. If training is to be successful, it is critical that we provide aircraft inspectors with appropriate training tools and environment. In response to this need, the paper outlines the development of a virtual reality (VR) system for aircraft inspection training. VR has generated much excitement but little formal proof that it is useful. However, since VR interfaces are difficult and expensive to build, the computer graphics community needs to be able to predict which applications will benefit from VR. To address this important issue, this research measured the degree of immersion and presence felt by subjects in a virtual environment simulator. Specifically, it conducted two controlled studies using the VR system developed for visual inspection task of an aft-cargo bay at the VR Lab of Clemson University. Beyond assembling the visual inspection virtual environment, a significant goal of this project was to explore subjective presence as it affects task performance. The results of this study indicated that the system scored high on the issues related to the degree of presence felt by the subjects. As a next logical step, this study, then, compared VR to an existing PC-based aircraft inspection simulator. The results showed that the VR system was better and preferred over the PC-based training tool.

  10. 19 CFR 191.133 - Explanation of terms.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Explanation of terms. 191.133 Section 191.133 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE... or aircraft, changes the type of the vessel or aircraft, substantially prolongs the life of the...

  11. Non-Destructive Inspection of Impact Damage in Composite Aircraft Panels by Ultrasonic Guided Waves and Statistical Processing

    Directory of Open Access Journals (Sweden)

    Margherita Capriotti

    2017-06-01

    Full Text Available This paper discusses a non-destructive evaluation (NDE technique for the detection of damage in composite aircraft structures following high energy wide area blunt impact (HEWABI from ground service equipment (GSE, such as heavy cargo loaders and other heavy equipment. The test structures typically include skin, co-cured stringers, and C-frames that are bolt-connected onto the skin with shear ties. The inspection exploits the waveguide geometry of these structures by utilizing ultrasonic guided waves and a line scan approach. Both a contact prototype and a non-contact prototype were developed and tested on realistic test panels subjected to impact in the laboratory. The results are presented in terms of receiver operating characteristic curves that show excellent probability of detection with low false alarm rates for defects located in the panel skin and stringers.

  12. Non-Destructive Inspection of Impact Damage in Composite Aircraft Panels by Ultrasonic Guided Waves and Statistical Processing.

    Science.gov (United States)

    Capriotti, Margherita; Kim, Hyungsuk E; Scalea, Francesco Lanza di; Kim, Hyonny

    2017-06-04

    This paper discusses a non-destructive evaluation (NDE) technique for the detection of damage in composite aircraft structures following high energy wide area blunt impact (HEWABI) from ground service equipment (GSE), such as heavy cargo loaders and other heavy equipment. The test structures typically include skin, co-cured stringers, and C-frames that are bolt-connected onto the skin with shear ties. The inspection exploits the waveguide geometry of these structures by utilizing ultrasonic guided waves and a line scan approach. Both a contact prototype and a non-contact prototype were developed and tested on realistic test panels subjected to impact in the laboratory. The results are presented in terms of receiver operating characteristic curves that show excellent probability of detection with low false alarm rates for defects located in the panel skin and stringers.

  13. Aircraft Wiring Support Equipment Integration Laboratory (AWSEIL)

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose:The Aircraft Wiring Support Equipment Integration Laboratory (AWSEIL) provides a variety of research, design engineering and prototype fabrication services...

  14. Aircrew exposure onboard a Czech airlines aircraft, individual monitoring of aircrew

    Energy Technology Data Exchange (ETDEWEB)

    Ploc, O.; Spurny, F.; Turek, K. [Nuclear Physics Institute AS CR, Dept. of Radiation Dosimetry, Prague (Czech Republic); Ploc, O. [Czech Technical Univ., Dept. of Dosimetry and Application of Ionizing Radiation, Prague (Czech Republic)

    2006-07-01

    The contribution presents new results related to the aircraft crew exposure onboard aircraft of Czech air companies. First the results of long term monitoring onboard of an aircraft of Czech Airlines are presented. The monitoring has been performed in the period May - December 2005, more than 500 individual flights have been followed. M.D.U.-Liulin Si-diode based spectrometer was used, together with thermoluminescent and track detectors. Total effective dose was about 12 mSv, the results obtained with dosimeters mentioned are analyzed and compared with the results of calculation performed with C.A.R.I. and E.P.C.A.R.D. codes. Individual monitoring of air crew members has been started in the Czech Republic since 1998 year. The results obtained during few last years are presented, general tendencies of aircraft crew onboard exposure of Czech air companies are outlined. (authors)

  15. Treinamento isocinético de curto prazo promove aumento da força muscular em indivíduos jovens Short-term isokinetic training increases muscle strength in young subjects

    Directory of Open Access Journals (Sweden)

    Rafael Cunha

    2011-03-01

    Full Text Available O objetivo foi avaliar os efeitos de treinamento isocinético de curta duração no desempenho muscular em indivíduos jovens. Onze homens sadios participaram de um programa de treinamento isocinético de curta duração, composto por 3 sessões (4 séries; 10 repetições isocinéticas concêntricas a 120º.s-1; 2 minutos de intervalo entre séries. A reprodutibilidade dos dados de 2 sessões foi avaliada pelo coeficiente de correlação intraclasses (CCI e teste de Bland e Altman. As avaliações do treinamento foram aplicadas pré e pós a 2ª e 3ª sessões (1 série; 3 repetições concêntricas de extensão do joelho a 60º.s-1, 120º.s-1 e 180º.s-1. Utilizou-se a ANOVA para medidas repetidas e post-hoc de Tukey para verificar diferenças nos testes. O CCI variou de 0,97 a 0,98 em todas as velocidades. Ocorreu um aumento no pico de torque a 60º.s-1 (P=0,03 e 120º.s-1 (P=0,01 após 2 sessões de treinamento. Sugere-se que duas sessões de exercício isocinético foram suficientes para induzir ganhos de força na velocidade treinada (120º.s-1 e em velocidade de contração mais lenta (60º.s-1, em indivíduos jovens.The aim was to investigate the effects of short-term isokinetic training on muscle performance in young individuals. Eleven healthy males subjects underwent to short-term training, consisting of 3 sessions (4 sets, 10 repetitions of concentric isokinetic exercise at 120º.s-1; 2-minute interval between sets. Data reproducibility from two sessions was evaluated by intraclass correlation coefficient (ICC and Bland and Altman test. Training assessments were made pre and post the 2nd and 3rd sessions (1 set, 3 repetitions of concentric knee extension at 60º.s-1, 120º.s-1 and 180º.s-1. An ANOVA for repeated measures and Tukey post-hoc test was applied to determine differences between tests. The ICC ranged from 0.97 to 0.98 for all velocities. There was an increase in peak torque at 60º.s-1 (P=0,03 and 120º.s-1 (P=0,01 after 2

  16. Aging Aircraft Fleets: Structural and Other Subsystem Aspects (le Vieillissement des flottes d’avions militaires : aspects structures et autres sous-systemes)

    Science.gov (United States)

    2001-03-01

    more accurate loads databases in terms of - advances in “Carefree Handling”- Flight Control Systems (FCS) - aircraft mass distributions predictions...aging aircraft structures. An advanced system known as COMSCAN, developed by Phillips, allows to form images of underlying structure and requires access...detect damage in aircraft structures. Some of the techniques being- shearography , DIAS system and thermography. Shearography - This is a field inspection

  17. 75 FR 51953 - Notification and Reporting of Aircraft Accidents or Incidents and Overdue Aircraft, and...

    Science.gov (United States)

    2010-08-24

    ... notification and reporting of aircraft accidents or incidents by adding a definition of ``unmanned aircraft... Register (FR), is available for inspection and copying in the NTSB's public reading room, located at 490 L... the addition of a new definition of ``unmanned aircraft accident'' to the section of the NTSB's...

  18. 77 FR 1626 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engine

    Science.gov (United States)

    2012-01-11

    ... Equipped With Rotax Aircraft Engines 912 A Series Engine AGENCY: Federal Aviation Administration (FAA), DOT...'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), (3) Will not affect... Aircraft model Engine model Aeromot-Ind stria AMT-200 912 A2 Mec nico- Metal rgica Ltda. Diamond Aircraft...

  19. COMPARATIVE ANALYSIS OF TRANSPORT AIRCRAFT, BACKROUND FOR SHORT/ MEDIUM COURIER TRANSPORT AIRCRAFT PROCUREMENT

    Directory of Open Access Journals (Sweden)

    Matei POPA

    2010-03-01

    Full Text Available In accordance with Air Force requirements, the comparative analysis of short/medium transport aircraft comes to sustain procurement decision of short/medium transport aircraft. This paper presents, in short, the principles and the results of the comparative analysis for short/medium military transport aircraft.

  20. Hydrant refueling system as an optimisation of aircraft refuelling

    Directory of Open Access Journals (Sweden)

    Martin HROMÁDKA

    2015-09-01

    Full Text Available At large international airports, aircraft can be refuelled either by fuel trucks or using dedicated underground pipeline systems. The latter, hydrant refuelling, is considered to be an optimal fuelling method as it increases safety, shortens the aircraft turnaround time and cuts the overall costs. However, at smaller airports, implementation of this system can lead to high investment costs. Thus, the paper discusses the airport size from which this system may be efficient to implement. Various definitions of term “airport size” are assessed. Based on data collection, the hydrant system model is created within the paper. As a result, methodology for assessing the suitability of hydrant system implementation is set. This methodology can be used at every airport using three simple inputs.

  1. Effects of Inertial and Geometric Nonlinearities in the Simulation of Flexible Aircraft Dynamics

    Science.gov (United States)

    Bun Tse, Bosco Chun

    This thesis examines the relative importance of the inertial and geometric nonlinearities in modelling the dynamics of a flexible aircraft. Inertial nonlinearities are derived by employing an exact definition of the velocity distribution and lead to coupling between the rigid body and elastic motions. The geometric nonlinearities are obtained by applying nonlinear theory of elasticity to the deformations. Peters' finite state unsteady aerodynamic model is used to evaluate the aerodynamic forces. Three approximate models obtained by excluding certain combinations of nonlinear terms are compared with that of the complete dynamics equations to obtain an indication of which terms are required for an accurate representation of the flexible aircraft behavior. A generic business jet model is used for the analysis. The results indicate that the nonlinear terms have a significant effect for more flexible aircraft, especially the geometric nonlinearities which leads to increased damping in the dynamics.

  2. Assessment of Alternative Aircraft Fuels

    Science.gov (United States)

    1984-01-01

    The purpose of this symposium is to provide representatives from industry, government, and academia concerned with the availability and quality of future aviation turbine fuels with recent technical results and a status review of DOD and NASA sponsored fuels research projects. The symposium has included presentations on the potential crude sources, refining methods, and characteristics of future fuels; the effects of changing fuel characteristics on the performance and durability of jet aircraft components and systems; and the prospects for evolving suitable technology to produce and use future fuels.

  3. Technology for aircraft energy efficiency

    Science.gov (United States)

    Klineberg, J. M.

    1977-01-01

    Six technology programs for reducing fuel use in U.S. commercial aviation are discussed. The six NASA programs are divided into three groups: Propulsion - engine component improvement, energy efficient engine, advanced turboprops; Aerodynamics - energy efficient transport, laminar flow control; and Structures - composite primary structures. Schedules, phases, and applications of these programs are considered, and it is suggested that program results will be applied to current transport derivatives in the early 1980s and to all-new aircraft of the late 1980s and early 1990s.

  4. Altus I aircraft on lakebed

    Science.gov (United States)

    1997-01-01

    The remotely-piloted Altus I aircraft climbs away after takeoff from Rogers Dry Lake adjacent to NASA's Dryden Flight Research Center, Edwards, Calif. The short series of test flights sponsored by the Naval Postgraduate School in early August, 1997, were designed to demonstrate the ability of the experimental craft to cruise at altitudes above 40,000 feet for sustained durations. On its final flight Aug. 15, the Altus I reached an altitude of 43,500 feet. The Altus I and its sister ship, the Altus II, are variants of the Predator surveillance drone built by General Atomics/Aeronautical Systems, Inc. They are designed for high-altitude, long-duration scientific sampling missions, and are powered by turbocharged piston engines. The Altus I incorporates a single-stage turbocharger, while the Altus II, built for NASA's Environmental Research Aircraft and Sensor Technology program, sports a two-stage turbocharger to enable the craft to fly at altitudes above 55,000 feet. The Altus II, the first of the two craft to be completed, made its first flight on May 1, 1996. With its engine augmented by a single-stage turbocharger, the Altus II reached an altitude of 37,000 ft during its first series of development flights at Dryden in Aug., 1996. In Oct. of that year, the Altus II was flown in an Atmospheric Radiation Measurement study for the Department of Energy's Sandia National Laboratory in Oklahoma. During the course of those flights, the Altus II set a single-flight endurance record for remotely-operated aircraft of more than 26 hours. The Altus I, completed in 1997, flew a series of development flights at Dryden that summer. Those test flights culminated with the craft reaching an altitude of 43,500 ft while carrying a simulated 300-lb payload, a record for an unmanned aircraft powered by a piston engine augmented with a single-stage turbocharger. The Altus II sustained an altitudeof 55,000 feet for four hours in 1999. A pilot in a control station on the ground flies the

  5. Breast cancer and exposure to aircraft, road, and railway-noise: a case-control study based on health insurance records.

    Science.gov (United States)

    Hegewald, Janice; Schubert, Melanie; Wagner, Mandy; Dröge, Patrik; Prote, Ursel; Swart, Enno; Möhler, Ulrich; Zeeb, Hajo; Seidler, Andreas

    2017-11-01

    Objectives Aircraft, road, and rail traffic noise can cause sleep disturbances. Since night work and shorter sleep durations have been linked to increased risks of breast cancer, we examined if 24-hour, or day- or night-time traffic noise exposure may also increase the risk of breast cancer. Methods To investigate the noise-related risks of breast cancer, the pseudonymized insurance records of three large statutory health companies (2005-2010) for women aged ≥40 years living in the region surrounding the Frankfurt international airport were analyzed with address-specific acoustic data representing aircraft, road, and rail-traffic noise. Noise exposure among women with incident breast cancer (N=6643) were compared with that of control subjects (N=471 596) using logistic regression and adjusting for age, hormone replacement therapy, education and occupation (only available for 27.9%), and a regional proportion of persons receiving long-term unemployment benefits as an ecological indicator of socioeconomic level. Analyses were also stratified according to estrogen receptor (ER) status. Results An increased odds ratio (OR) was observed for ER negative (ER-) tumors at 24-hour aircraft noise levels 55-59 dB [OR 55-59 dB 1.41, 95% confidence interval (CI) 1.04-1.90] but not for ER positive (ER+) breast cancers (OR 55-59 dB 0.95, 95% CI 0.75-1.20). Clear associations between road and rail traffic noise were not observed. Conclusions The results indicate increased aircraft noise may be an etiologic factor for ER- breast cancers. However, information regarding potential confounding factors was largely unattainable. Further research is required to understand how environmental noise may be involved in the pathogenesis of ER- breast cancers.

  6. New entrants and overcapacity: lessons from regional aircraft manufacturing

    NARCIS (Netherlands)

    Steenhuis, H.J.; de Bruijn, E.J.; Heerkens, Johannes M.G.

    2010-01-01

    The commercial aircraft manufacturing industry has been largely dominated by the advanced economies in North America and Western Europe. During recent decades, several emerging economies have invested heavily in the commercial aircraft industry, notably in regional aircraft manufacturing. This paper

  7. Social-Ecological Soundscapes: Examining Aircraft-Harvester-Caribou Conflict in Arctic Alaska

    Science.gov (United States)

    Stinchcomb, Taylor R.

    As human development expands across the Arctic, it is crucial to carefully assess the impacts to remote natural ecosystems and to indigenous communities that rely on wild resources for nutritional and cultural wellbeing. Because indigenous communities and wildlife populations are interdependent, assessing how human activities impact traditional harvest practices can advance our understanding of the human dimensions of wildlife management. Indigenous communities across Arctic Alaska have expressed concern over the last four decades that low-flying aircraft interfere with their traditional harvest practices. For example, communities often have testified that aircraft disturb caribou (Rangifer tarandus) and thereby reduce harvest opportunities. Despite this longstanding concern, little research exists on the extent of aircraft activity in Arctic Alaska and on how aircraft affect the behavior and perceptions of harvesters. Therefore, the overarching goal of my research was to highlight the importance of aircraft-harvester conflict in Arctic Alaska and begin to address the issue using a scientific and community-driven approach. In Chapter 1, I demonstrated that conflict between aircraft and indigenous harvesters in Arctic Alaska is a widespread, understudied, and complex issue. By conducting a meta-analysis of the available literature, I quantified the deficiency of scientific knowledge about the impacts of aircraft on rural communities and traditional harvest practices in the Arctic. My results indicated that no peer-reviewed literature has addressed the conflict between low-flying aircraft and traditional harvesters in Arctic Alaska. I speculated that the scale over which aircraft, rural communities, and wildlife interact limits scientists' ability to determine causal relationships and therefore detracts from their interest in researching the human dimension of this social-ecological system. Innovative research approaches like soundscape ecology could begin to

  8. Point-Mass Aircraft Trajectory Prediction Using a Hierarchical, Highly-Adaptable Software Design

    Science.gov (United States)

    Karr, David A.; Vivona, Robert A.; Woods, Sharon E.; Wing, David J.

    2017-01-01

    A highly adaptable and extensible method for predicting four-dimensional trajectories of civil aircraft has been developed. This method, Behavior-Based Trajectory Prediction, is based on taxonomic concepts developed for the description and comparison of trajectory prediction software. A hierarchical approach to the "behavioral" layer of a point-mass model of aircraft flight, a clear separation between the "behavioral" and "mathematical" layers of the model, and an abstraction of the methods of integrating differential equations in the "mathematical" layer have been demonstrated to support aircraft models of different types (in particular, turbojet vs. turboprop aircraft) using performance models at different levels of detail and in different formats, and promise to be easily extensible to other aircraft types and sources of data. The resulting trajectories predict location, altitude, lateral and vertical speeds, and fuel consumption along the flight path of the subject aircraft accurately and quickly, accounting for local conditions of wind and outside air temperature. The Behavior-Based Trajectory Prediction concept was implemented in NASA's Traffic Aware Planner (TAP) flight-optimizing cockpit software application.

  9. Multidisciplinary Shape Optimization of a Composite Blended Wing Body Aircraft

    Science.gov (United States)

    Boozer, Charles Maxwell

    A multidisciplinary shape optimization tool coupling aerodynamics, structure, and performance was developed for battery powered aircraft. Utilizing high-fidelity computational fluid dynamics analysis tools and a structural wing weight tool, coupled based on the multidisciplinary feasible optimization architecture; aircraft geometry is modified in the optimization of the aircraft's range or endurance. The developed tool is applied to three geometries: a hybrid blended wing body, delta wing UAS, the ONERA M6 wing, and a modified ONERA M6 wing. First, the optimization problem is presented with the objective function, constraints, and design vector. Next, the tool's architecture and the analysis tools that are utilized are described. Finally, various optimizations are described and their results analyzed for all test subjects. Results show that less computationally expensive inviscid optimizations yield positive performance improvements using planform, airfoil, and three-dimensional degrees of freedom. From the results obtained through a series of optimizations, it is concluded that the newly developed tool is both effective at improving performance and serves as a platform ready to receive additional performance modules, further improving its computational design support potential.

  10. Large-scale design of supersonic aircraft via collaborative optimization

    Science.gov (United States)

    Manning, Valerie Michelle

    The design of supersonic aircraft requires complex analysis in multiple disciplines, posing a challenge for multidisciplinary optimization methods. In this thesis, collaborative optimization, a design architecture developed to solve large-scale multidisciplinary design problems, is applied to the design of supersonic transport concepts. Collaborative optimization, takes advantage of natural disciplinary segmentation to facilitate parallel execution of design tasks. Discipline-specific design optimization proceeds while a coordinating mechanism ensures progress toward an optimum and compatibility between disciplinary designs. Two concepts for supersonic aircraft are investigated: a conventional delta-wing design and a natural laminar flow concept that achieves improved performance by exploiting properties of supersonic flow to delay boundary layer transition. The work involves the development of aerodynamics and structural analyses, and integration within a collaborative optimization framework. Response surface estimation and reduced basis modeling were used to reduce the computational expense of the optimization and to ensure smooth analytic gradients. Both design problems converged successfully. In each problem, the system optimizer minimized aircraft take-off weight with respect to global and disciplinary design variables, subject to aeroelastic and performance constraints. In previous work, the method successfully solved simple and medium fidelity problems. The current work demonstrates collaborative optimization with large-scale designs using industry-standard analyses. The research shows that collaborative optimization is a valuable method for large-scale design, ready for real-world implementation.

  11. Analysis of operational limit of an aircraft: An aeroelastic approach

    Science.gov (United States)

    Hasan, Md. Mehedi; Hassan, M. D. Mehedi; Sarrowar, S. M. Bayazid; Faisal, Kh. Md.; Ahmed, Sheikh Reaz, Dr.

    2017-06-01

    In classical theory of elasticity, external loading acting on the body is independent of deformation of the body. But, in aeroelasticity, aerodynamic forces depend on the attitude of the body relative to the flow. Aircraft's are subjected to a range of static loads resulting from equilibrium or steady flight maneuvers such as coordinated level turn, steady pitch and bank rate, steady and level flight. Interaction of these loads with elastic forces of aircraft structure creates some aeroelastic phenomena. In this paper, we have summarized recent developments in the area of aeroelasticity. A numerical approach has been applied for finding divergence speed, a static aeroelastic phenomena, of a typical aircraft. This paper also involves graphical representations of constraints on load factor and bank angle during different steady flight maneuvers taking flexibility into account and comparing it with the value without flexibility. Effect of wing skin thickness, spar web thickness and position of flexural axis of wing on this divergence speed as well as load factor and bank angle has also been observed using MATLAB.

  12. Noise-Induced Building Vibrations Caused by Concorde and Conventional Aircraft Operations at Dulles and Kennedy International Airports

    Science.gov (United States)

    Mayes, W. H.; Stephens, D. G.; Holmes, H. K.; Lewis, R. B.; Holliday, B. G.; Ward, D. W.; Deloach, R.; Cawthorn, J. M.; Finley, T. D.; Lynch, J. W.

    1978-01-01

    Outdoor and indoor noise levels resulting from aircraft flyovers and certain nonaircraft events were recorded, as were the associated vibration levels in the walls, windows, and floors at building test sites. In addition, limited subjective tests were conducted to examine the human detection and annoyance thresholds for building vibration and rattle caused by aircraft noise. Representative peak levels of aircraft noise-induced building vibrations are reported and comparisons are made with structural damage criteria and with vibration levels induced by common domestic events. In addition, results of a pilot study are reported which indicate the human detection threshold for noise-induced floor vibrations.

  13. 14 CFR 121.538 - Aircraft security.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Aircraft security. 121.538 Section 121.538 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS..., FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.538 Aircraft security. Certificate holders...

  14. Bayesian Inference of Aircraft Initial Mass

    NARCIS (Netherlands)

    Sun, J.; Ellerbroek, J.; Hoekstra, J.M.

    2017-01-01

    Aircraft mass is a crucial piece of information for studies on aircraft performance, trajectory prediction, and many other ATM topics. However, it is a common challenge for researchers who have no access to this proprietary information. Previously, several studies have proposed methods to estimates

  15. Cycle Counting Methods of the Aircraft Engine

    Science.gov (United States)

    Fedorchenko, Dmitrii G.; Novikov, Dmitrii K.

    2016-01-01

    The concept of condition-based gas turbine-powered aircraft operation is realized all over the world, which implementation requires knowledge of the end-of-life information related to components of aircraft engines in service. This research proposes an algorithm for estimating the equivalent cyclical running hours. This article provides analysis…

  16. Aircraft of Today. Aerospace Education I.

    Science.gov (United States)

    Savler, D. S.

    This textbook gives a brief idea about the modern aircraft used in defense and for commercial purposes. Aerospace technology in its present form has developed along certain basic principles of aerodynamic forces. Different parts in an airplane have different functions to balance the aircraft in air, provide a thrust, and control the general…

  17. AIRCRAFT SHELTER-DICE THROW Data Report

    Science.gov (United States)

    1977-03-01

    SHELTER-OICE THROW Test Site Layout for 9 AFWL Test Structures 4 AIRCRAFT SHELTER-DICE THROW ANFO Charge Configuration 10 5 Upgraded Aircraft Shelter...approximately 150 meters (500 ft). This shelter is the same as Shelter "$", but with a heavy overlay of concrete. As with Shelter "B", end walls were

  18. Aircraft Manufacturing Occupations. Aviation Careers Series.

    Science.gov (United States)

    Zaharevitz, Walter

    This booklet, one in a series on aviation careers, outlines the variety of careers available in the aircraft manufacturing industry. The first part of the booklet provides general information about careers in the aerospace industry (of which aircraft manufacturing is one part), including the numbers of various types of workers employed in those…

  19. Study on Impedance Characteristics of Aircraft Cables

    Directory of Open Access Journals (Sweden)

    Weilin Li

    2016-01-01

    Full Text Available Voltage decrease and power loss in distribution lines of aircraft electric power system are harmful to the normal operation of electrical equipment and may even threaten the safety of aircraft. This study investigates how the gap distance (the distance between aircraft cables and aircraft skin and voltage frequency (variable frequency power supply will be adopted for next generation aircraft will affect the impedance of aircraft cables. To be more precise, the forming mechanism of cable resistance and inductance is illustrated in detail and their changing trends with frequency and gap distance are analyzed with the help of electromagnetic theoretical analysis. An aircraft cable simulation model is built with Maxwell 2D and the simulation results are consistent with the conclusions drawn from the theoretical analysis. The changing trends of the four core parameters of interest are analyzed: resistance, inductance, reactance, and impedance. The research results can be used as reference for the applications in Variable Speed Variable Frequency (VSVF aircraft electric power system.

  20. A Turbo-Brayton Cryocooler for Aircraft Superconducting Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Hybrid turboelectric aircraft with gas turbines driving electric generators connected to electric propulsion motors have the potential to transform the aircraft...

  1. An Instrument to Measure Aircraft Sulfate Particle Emissions Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aircraft particle emissions contribute a modest, but growing, portion of the overall particle emissions budget. Characterizing aircraft particle emissions is...

  2. Partially Turboelectric Aircraft Drive Key Performance Parameters

    Science.gov (United States)

    Jansen, Ralph H.; Duffy, Kirsten P.; Brown, Gerald V.

    2017-01-01

    The purpose of this paper is to propose electric drive specific power, electric drive efficiency, and electrical propulsion fraction as the key performance parameters for a partially turboelectric aircraft power system and to investigate their impact on the overall aircraft performance. Breguet range equations for a base conventional turbofan aircraft and a partially turboelectric aircraft are found. The benefits and costs that may result from the partially turboelectric system are enumerated. A break even analysis is conducted to find the minimum allowable electric drive specific power and efficiency, for a given electrical propulsion fraction, that can preserve the range, fuel weight, operating empty weight, and payload weight of the conventional aircraft. Current and future power system performance is compared to the required performance to determine the potential benefit.

  3. Pilot Preferences on Displayed Aircraft Control Variables

    Science.gov (United States)

    Trujillo, Anna C.; Gregory, Irene M.

    2013-01-01

    The experiments described here explored how pilots want available maneuver authority information transmitted and how this information affects pilots before and after an aircraft failure. The aircraft dynamic variables relative to flight performance were narrowed to energy management variables. A survey was conducted to determine what these variables should be. Survey results indicated that bank angle, vertical velocity, and airspeed were the preferred variables. Based on this, two displays were designed to inform the pilot of available maneuver envelope expressed as bank angle, vertical velocity, and airspeed. These displays were used in an experiment involving control surface failures. Results indicate the displayed limitations in bank angle, vertical velocity, and airspeed were helpful to the pilots during aircraft surface failures. However, the additional information did lead to a slight increase in workload, a small decrease in perceived aircraft flying qualities, and no effect on aircraft situation awareness.

  4. Performance and benefits of an advanced technology supersonic cruise aircraft

    Science.gov (United States)

    Fitzsimmons, R. D.

    1976-01-01

    The results of four years research on technology are synthesized in an advanced supersonic cruise aircraft design. Comparisons are presented with the former United States SST and the British-French Concorde, including aerodynamic efficiency, propulsion efficiency, weight efficiency, and community noise. Selected trade study results are presented on the subjects of design cruise Mach number, engine cycle selection, and noise suppression. The critical issue of program timing is addressed and some observations made regarding the impact that timing has on engine selection and minimization of program risk.

  5. Short-Term Effects of Whole-Body Vibration Combined with Task-Related Training on Upper Extremity Function, Spasticity, and Grip Strength in Subjects with Poststroke Hemiplegia: A Pilot Randomized Controlled Trial.

    Science.gov (United States)

    Lee, Jung-Sun; Kim, Chang-Yong; Kim, Hyeong-Dong

    2016-08-01

    The aim of this study was to determine the effect of whole-body vibration training combined with task-related training on arm function, spasticity, and grip strength in subjects with poststroke hemiplegia. Forty-five subjects with poststroke were randomly allocated to 3 groups, each with 15 subjects as follows: control group, whole-body vibration group, and whole-body vibration plus task-related training group. Outcome was evaluated by clinical evaluation and measurements of the grip strength before and 4 weeks after intervention. Our results show that there was a significantly greater increase in the Fugl-Meyer scale, maximal grip strength of the affected hand, and grip strength normalized to the less affected hand in subjects undergoing the whole-body vibration training compared with the control group after the test. Furthermore, there was a significantly greater increase in the Wolf motor function test and a decrease in the modified Ashworth spasticity total scores in subjects who underwent whole-body vibration plus task-related training compared with those in the other 2 groups after the test. The findings indicate that the use of whole-body vibration training combined with task-related training has more benefits on the improvement of arm function, spasticity, and maximal grip strength than conventional upper limb training alone or with whole-body vibration in people with poststroke hemiplegia.

  6. The influence of ozone on self-evaluation of symptoms in a simulated aircraft cabin

    DEFF Research Database (Denmark)

    Strøm-Tejsen, Peter; Weschler, Charles J.; Wargocki, Pawel

    2008-01-01

    Simulated 4-h flights were carried out in a realistic model of a three-row, 21-seat section of an aircraft cabin that was reconstructed inside a climate chamber. Twenty-nine female subjects, age 19-27 years, were split into two groups; each group was exposed to four conditions: two levels of ozone (...

  7. The influence of activities and duration on comfort and discomfort development in time of aircraft passengers

    NARCIS (Netherlands)

    Hiemstra-Van Mastright, S.; Meyenborg, I.; Hoogenhout, M.

    2016-01-01

    BACKGROUND: Discomfort increases when duration of sitting is longer. Aircraft passengers are subjected to prolonged sitting in restricted postures, which can cause discomfort. OBJECTIVE: To examine the relationship between duration of sitting and development of discomfort, as well as the influence

  8. Neck injury criteria and certification procedure for side-facing aircraft seats

    NARCIS (Netherlands)

    Philippens, M.M.G.M.; Forbes, P.A.; Wismans, J.S.H.M.; DeWeese, R.; Moorcroft, D.

    2011-01-01

    This report documents research started in 2002 that identified the potential need for explicit neck injury criteria and tolerances for certification of side-facing seats in aircraft. Laboratory sled tests with full-body postmortem human subjects proved that there is a substantial risk for serious

  9. Cosmic radiation exposure of aircraft crew: compilation of measured and calculated data

    Czech Academy of Sciences Publication Activity Database

    Lindborg, L.; Bartlett, D.; Beck, P.; McAulay, I.; Schnuer, K.; Schraube, H.; Spurný, František

    2004-01-01

    Roč. 110, 1-4 (2004), s. 417-422 ISSN 0144-8420 Grant - others:EC project(XE) FIGM-CT2000-00068 Institutional research plan: CEZ:AV0Z1048901 Keywords : cosmic radiation exposure * aircraft crew * measurement Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.617, year: 2003

  10. Radiative forcing from particle emissions by future supersonic aircraft

    Directory of Open Access Journals (Sweden)

    G. Pitari

    2008-07-01

    Full Text Available In this work we focus on the direct radiative forcing (RF of black carbon (BC and sulphuric acid particles emitted by future supersonic aircraft, as well as on the ozone RF due to changes produced by emissions of both gas species (NOx, H2O and aerosol particles capable of affecting stratospheric ozone chemistry. Heterogeneous chemical reactions on the surface of sulphuric acid stratospheric particles (SSA-SAD are the main link between ozone chemistry and supersonic aircraft emissions of sulphur precursors (SO2 and particles (H2O–H2SO4. Photochemical O3 changes are compared from four independent 3-D atmosphere-chemistry models (ACMs, using as input the perturbation of SSA-SAD calculated in the University of L'Aquila model, which includes on-line a microphysics code for aerosol formation and growth. The ACMs in this study use aircraft emission scenarios for the year 2050 developed by AIRBUS as a part of the EU project SCENIC, assessing options for fleet size, engine technology (NOx emission index, Mach number, range and cruising altitude. From our baseline modeling simulation, the impact of supersonic aircraft on sulphuric acid aerosol and BC mass burdens is 53 and 1.5 μg/m2, respectively, with a direct RF of −11.4 and 4.6 mW/m2 (net RF=−6.8 mW/m2. This paper discusses the similarities and differences amongst the participating models in terms of changes to O3 precursors due to aircraft emissions (NOx, HOx,Clx,Brx and the stratospheric ozone sensitivity to them. In the baseline case, the calculated global ozone change is −0.4 ±0.3 DU, with a net radiative forcing (IR+UV of −2.5± 2 mW/m2. The fraction of this O3-RF attributable to SSA-SAD changes is, however, highly variable among the models, depending on the NOx removal

  11. Do supersonic aircraft avoid contrails?

    Directory of Open Access Journals (Sweden)

    A. Stenke

    2008-02-01

    Full Text Available The impact of a potential future fleet of supersonic aircraft on contrail coverage and contrail radiative forcing is investigated by means of simulations with the general circulation model ECHAM4.L39(DLR including a contrail parameterization. The model simulations consider air traffic inventories of a subsonic fleet and of a combined fleet of sub- and supersonic aircraft for the years 2025 and 2050, respectively. In case of the combined fleet, part of the subsonic fleet is replaced by supersonic aircraft. The combined air traffic scenario reveals a reduction in contrail cover at subsonic cruise levels (10 to 12 km in the northern extratropics, especially over the North Atlantic and North Pacific. At supersonic flight levels (18 to 20 km, contrail formation is mainly restricted to tropical regions. Only in winter is the northern extratropical stratosphere above the 100 hPa level cold enough for the formation of contrails. Total contrail coverage is only marginally affected by the shift in flight altitude. The model simulations indicate a global annual mean contrail cover of 0.372% for the subsonic and 0.366% for the combined fleet in 2050. The simulated contrail radiative forcing is most closely correlated to the total contrail cover, although contrails in the tropical lower stratosphere are found to be optically thinner than contrails in the extratropical upper troposphere. The global annual mean contrail radiative forcing in 2050 (2025 amounts to 24.7 mW m−2 (9.4 mW m−2 for the subsonic fleet and 24.2 mW m−2 (9.3 mW m−2 for the combined fleet. A reduction of the supersonic cruise speed from Mach 2.0 to Mach 1.6 leads to a downward shift in contrail cover, but does not affect global mean total contrail cover and contrail radiative forcing. Hence the partial substitution of subsonic air traffic leads to a shift of contrail occurrence from mid to low latitudes, but the resulting change in

  12. A Commercial Aircraft Fuel Burn and Emissions Inventory for 2005–2011

    Directory of Open Access Journals (Sweden)

    Donata K. Wasiuk

    2016-06-01

    Full Text Available The commercial aircraft fuel burn and emission estimates of CO2, CO, H2O, hydrocarbons, NOx and SOx for 2005–2011 are given as the 4-D Aircraft Fuel Burn and Emissions Inventory. On average, the annual fuel burn and emissions of CO2, H2O, NOx, and SOx increased by 2%–3% for 2005–2011, however, annual CO and HC emissions decreased by 1.6% and 8.7%, respectively because of improving combustion efficiency in recent aircraft. Approximately 90% of the global annual aircraft NOx emissions were emitted in the NH between 2005 and 2011. Air traffic within the three main industrialised regions of the NH (Asia, Europe, and North America alone accounted for 80% of the global number of departures, resulting in 50% and 45% of the global aircraft CO2 and NOx emissions, respectively, during 2005–2011. The current Asian fleet appears to impact our climate strongly (in terms of CO2 and NOx when compared with the European and North American fleet. The changes in the geographical distribution and a gradual shift of the global aircraft NOx emissions as well as a subtle but steady change in regional emissions trends are shown in particular comparatively rising growth rates between 0 and 30°N and decreasing levels between 30 and 60°N.

  13. Determination and Applications of Environmental Costs at Different Sized Airports: Aircraft Noise and Engine Emissions

    Science.gov (United States)

    Lu, Cherie; Lierens, Abigail

    2003-01-01

    With the increasing trend of charging for externalities and the aim of encouraging the sustainable development of the air transport industry, there is a need to evaluate the social costs of these undesirable side effects, mainly aircraft noise and engine emissions, for different airports. The aircraft noise and engine emissions social costs are calculated in monetary terms for five different airports, ranging from hub airports to small regional airports. The number of residences within different levels of airport noise contours and the aircraft noise classifications are the main determinants for accessing aircraft noise social costs. Whist, based on the damages of different engine pollutants on the human health, vegetation, materials, aquatic ecosystem and climate, the aircraft engine emissions social costs vary from engine types to aircraft categories. The results indicate that the relationship appears to be curvilinear between environmental costs and the traffic volume of an airport. The results and methodology of environmental cost calculation could input for to the proposed European wide harmonized noise charges as well as the social cost benefit analysis of airports.

  14. Jellyfish monitoring on coastlines using remote piloted aircraft

    Science.gov (United States)

    Barrado, C.; Fuentes, J. A.; Salamí, E.; Royo, P.; Olariaga, A. D.; López, J.; Fuentes, V. L.; Gili, J. M.; Pastor, E.

    2014-03-01

    In the last 10 years the number of jellyfish shoals that reach the swimming area of the Mediterranean Sea are increasing constantly. The term "Jellyfish" refers to animals from different taxonomic groups but the Scyphomedusae are within the most significant one. Four species of Scyphomedusae are the most conspicuous ones inhabiting the studied area, the Barcelona metropolitan area. Jellyfish are usually found at the surface waters, forming big swarms. This feature makes possible to detect them remotely, using a visual camera and image processing algorithms. In this paper we present the characteristics of a remote piloted aircraft capable to perform monitoring flights during the whole summer season. The requirements of the aircraft are to be easy to operate, to be able to flight at low altitude (100 m) following the buoy line (200 m from the beach line) and to be save for other users of the seaside. The remote piloted aircraft will carry a vision system and a processing board able to obtain useful information on real-time.

  15. CFD analysis of aircraft fuel tanks thermal behaviour

    Science.gov (United States)

    Zilio, C.; Longo, G. A.; Pernigotto, G.; Chiacchio, F.; Borrelli, P.; D’Errico, E.

    2017-11-01

    This work is carried out within the FP7 European research project TOICA (Thermal Overall Integrated Conception of Aircraft, http://www.toica-fp7.eu/). One of the tasks foreseen for the TOICA project is the analysis of fuel tanks as possible heat sinks for future aircrafts. In particular, in the present paper, commercial regional aircraft is considered as case study and CFD analysis with the commercial code STAR-CCM+ is performed in order to identify the potential capability to use fuel stored in the tanks as a heat sink for waste heat dissipated by other systems. The complex physical phenomena that characterize the heat transfer inside liquid fuel, at the fuel-ullage interface and inside the ullage are outlined. Boundary conditions, including the effect of different ground and flight conditions, are implemented in the numerical simulation approach. The analysis is implemented for a portion of aluminium wing fuel tank, including the leading edge effects. Effect of liquid fuel transfer among different tank compartments and the air flow in the ullage is included. According to Fuel Tank Flammability Assessment Method (FTFAM) proposed by the Federal Aviation Administration, the results are exploited in terms of exponential time constants and fuel temperature difference to the ambient for the different cases investigated.

  16. 76 FR 6525 - Airworthiness Directives; Cessna Aircraft Company (Type Certificate Previously Held by Columbia...

    Science.gov (United States)

    2011-02-07

    ... Company (Type Certificate Previously Held by Columbia Aircraft Manufacturing (Previously the Lancair... Aircraft Company (Type Certificate Previously Held by Columbia Aircraft Manufacturing (Previously The... Aircraft Company (type certificate previously held by Columbia Aircraft Manufacturing (previously The...

  17. Youth Homelessness and Individualised Subjectivity

    Science.gov (United States)

    Farrugia, David

    2011-01-01

    This article aims to contribute to understandings of youth homelessness and subjectivity by analysing identity construction in terms of young people's negotiation of the structural and institutional environment of youth homelessness. I suggest that while existing literature on this topic concentrates mainly on micro-social encounters, the…

  18. Effects of short-term caloric restriction on circulating free IGF-I, acid-labile subunit, IGF-binding proteins (IGFBPs)-1-4, and IGFBPs-1-3 protease activity in obese subjects

    DEFF Research Database (Denmark)

    Rasmussen, Michael Højby; Juul, Anders; Kjems, Lise Lund

    2006-01-01

    Decreased levels of GH and total IGF-I have been reported in obesity. It has been hypothesized that increased free (biologically active) IGF-I levels generated from IGF-binding protein (IGFBP) protease activity could be the mechanism for the low GH release in dieting obese subjects. However...

  19. OPTIMAL AIRCRAFT CONTROL SYNTHESIS BASED ON THE EQUATIONS OF NON-LINEAR DYNAMICS

    Directory of Open Access Journals (Sweden)

    Viktor F. Dil

    2017-01-01

    Full Text Available The article considers the technique of the synthesis of non-linear aircraft control systems by flight optimization us- ing inverse dynamics problems. To synthesize control algorithms a non-linear model of aircraft flight and trajectory movement is used. The authors define method stages of flying level synthesis which include: selection of aircraft reference movements in accordance with three degrees of freedom, structuring the control algorithms and their parameters, defining the proximity of current and reference movements by means of a quadratic functional and further extremum-minimum movement organization by the gradient method. Through the optimized parameters of flying level the direct dynamics problem of trajectory level control of the aircraft spatial movement is solved. The basis for calculating the aircraft trajecto- ry parameters is a non-linear model of the trajectory movement for which flying level output parameters serve as input data. The trajectory level output parameters are defined by numerical integration of input signals considering aircraft dynamic blow coefficients. The structure diagram of aircraft spatial movement control organization is developed. The flight contour functioning is examined using numerical modeling in MathCad and Paskal programs. Reference parameters were deter- mined by Paskal simulation modeling according to the reaction of a non-linear aircraft model to the “bounces” of aerody- namical flight controls. It is shown that the spatial control problem is optimal in terms of input control realization. Besides, in comparison with [9] it is possible to state that due to energy reversibility of rotational and progressive movements only the content of direct and inversed problems of dynamics changes.

  20. Aircraft wing structure detail design

    Science.gov (United States)

    Sager, Garrett L.; Roberts, Ron; Mallon, Bob; Alameri, Mohamed; Steinbach, Bill

    1993-01-01

    The provisions of this project call for the design of the structure of the wing and carry-through structure for the Viper primary trainer, which is to be certified as a utility category trainer under FAR part 23. The specific items to be designed in this statement of work were Front Spar, Rear Spar, Aileron Structure, Wing Skin, and Fuselage Carry-through Structure. In the design of these parts, provisions for the fuel system, electrical system, and control routing were required. Also, the total weight of the entire wing planform could not exceed 216 lbs. Since this aircraft is to be used as a primary trainer, and the SOW requires a useful life of 107 cycles, it was decided that all of the principle stresses in the structural members would be kept below 10 ksi. The only drawback to this approach is a weight penalty.

  1. Long-term efficacy and safety of E/C/F/TDF vs EFV/FTC/TDF and ATV+RTV+FTC/TDF in HIV-1-infected treatment-naïve subjects ≥50 years.

    Science.gov (United States)

    Gazzard, Brian; Girard, Pierre Marie; Di Perri, Giovanni; Gallant, Joel; Towner, William; Rogatto, Felipe; Demorin, Jennifer; McColl, Damian; Liu, Hui; Rhee, Martin; Szwarcberg, Javier; Piontkowsky, David

    2014-01-01

    In high-income countries, ≥30% of HIV-infected patients are ≥50 years (yrs) old (UNAIDS 2013). In two phases, three clinical trials (Studies 102 and 103) elvitegravir/cobicistat/emtricitabine/tenofovir DF (E/C/F/TDF; STB) had non-inferior efficacy and favourable safety vs efavirenz/emtricitabine/tenofovir DF (EFV/FTC/TDF; ATR) or ritonavir-boosted atazanavir (ATV+RTV)+FTC/TDF (TVD) in HIV-infected, treatment-naïve subjects at Week 144. The efficacy and safety of STB in subjects < or ≥50 yrs is described. Post hoc analysis of efficacy, tolerability and safety in subjects < or ≥50 yrs at Week 144. Subjects ≥50 yrs in Study 102: STB: 14% (49/348), ATR: 16% (56/352); in Study 103: STB: 14% (48/353), ATV+RTV+TVD: 14% (48/355). Efficacy, safety and tolerability by age and study endpoint are shown in Table 1. Regardless of age, STB had robust efficacy at Week 144 with similar virologic outcomes vs ATR or ATV+RTV+TVD. Discontinuations (DC) due to AE on STB were similar to the comparators, most occurred by Week 48. Median changes in eGFR on STB were similar by age; DC with renal PRT was rare [STB: 4 (0.6%); ATV: 3 (0.8%); ATR: 0], 2 and 1 in ≥50 yrs old strata, respectively. STB compared to ATR or ATV+RTV+TVD, is an efficacious, well-tolerated and safe regimen for HIV-1-infected, treatment-naïve subjects

  2. Misconceptions of Electric Propulsion Aircraft and Their Emergent Aviation Markets

    Science.gov (United States)

    Moore, Mark D.; Fredericks, Bill

    2014-01-01

    create opportunities for the effective, near-term electric aircraft products. Without understanding both the context of how electric propulsion will integrate into the vehicle system, and evolve into the market place it is likely that electric propulsion will continue to be misunderstood.

  3. Turboprop aircraft against terrorism: a SWOT analysis of turboprop aircraft in CAS operations

    Science.gov (United States)

    Yavuz, Murat; Akkas, Ali; Aslan, Yavuz

    2012-06-01

    Today, the threat perception is changing. Not only for countries but also for defence organisations like NATO, new threat perception is pointing terrorism. Many countries' air forces become responsible of fighting against terorism or Counter-Insurgency (COIN) Operations. Different from conventional warfare, alternative weapon or weapon systems are required for such operatioins. In counter-terrorism operations modern fighter jets are used as well as helicopters, subsonic jets, Unmanned Aircraft Systems (UAS), turboprop aircraft, baloons and similar platforms. Succes and efficiency of the use of these platforms can be determined by evaluating the conditions, the threats and the area together. Obviously, each platform has advantages and disadvantages for different cases. In this research, examples of turboprop aircraft usage against terrorism and with a more general approach, turboprop aircraft for Close Air Support (CAS) missions from all around the world are reviewed. In this effort, a closer look is taken at the countries using turboprop aircraft in CAS missions while observing the fields these aircraft are used in, type of operations, specifications of the aircraft, cost and the maintenance factors. Thus, an idea about the convenience of using these aircraft in such operations can be obtained. A SWOT analysis of turboprop aircraft in CAS operations is performed. This study shows that turboprop aircraft are suitable to be used in counter-terrorism and COIN operations in low threat environment and is cost benefical compared to jets.

  4. Conceptual design of hybrid-electric transport aircraft

    Science.gov (United States)

    Pornet, C.; Isikveren, A. T.

    2015-11-01

    The European Flightpath 2050 and corresponding Strategic Research and Innovation Agenda (SRIA) as well as the NASA Environmentally Responsible Aviation N+ series have elaborated aggressive emissions and external noise reduction targets according to chronological waypoints. In order to deliver ultra-low or even zero in-flight emissions levels, there exists an increasing amount of international research and development emphasis on electrification of the propulsion and power systems of aircraft. Since the late 1990s, a series of experimental and a host of burgeouning commercial activities for fixed-wing aviation have focused on glider, ultra-light and light-sport airplane, and this is proving to serve as a cornerstone for more ambitious transport aircraft design and integration technical approaches. The introduction of hybrid-electric technology has dramatically expanded the design space and the full-potential of these technologies will be drawn through synergetic, tightly-coupled morphological and systems integration emphasizing propulsion - as exemplified by the potential afforded by distributed propulsion solutions. With the aim of expanding upon the current repository of knowledge associated with hybrid-electric propulsion systems a quad-fan arranged narrow-body transport aircraft equipped with two advanced Geared-Turbofans (GTF) and two Electrical Fans (EF) in an under-wing podded installation is presented in this technical article. The assessment and implications of an increasing Degree-of-Hybridization for Useful Power (HP,USE) on the overall sizing, performance as well as flight technique optimization of fuel-battery hybrid-electric aircraft is addressed herein. The integrated performance of the concept was analyzed in terms of potential block fuel burn reduction and change in vehicular efficiency in comparison to a suitably projected conventional aircraft employing GTF-only propulsion targeting year 2035. Results showed that by increasing HP,USE, significant

  5. Residents' annoyance responses to aircraft noise events

    Science.gov (United States)

    Dempsey, T. K.; Stephens, D. G.; Fields, J. M.; Shepherd, K. P.

    1983-01-01

    In a study conducted in the vicinity of Salt Lake City International Airport, community residents reported their annoyance with individual aircraft flyovers during rating sessions conducted in their homes. Annoyance ratings were obtained at different times of the day. Aircraft noise levels were measured, and other characteristics of the aircraft were noted by trained observers. Metrics commonly used for assessing aircraft noise were compared, but none performed significantly better than A-weighted sound pressure level. A significant difference was found between the ratings of commercial jet aircraft and general aviation propeller aircraft, with the latter being judged less annoying. After the effects of noise level were accounted for, no significant differences were found between the ratings of landings and takeoffs. Aircraft noise annoyance reactions are stronger in lowered ambient noise conditions. This is consistent with the theory that reduced nighttime and evening ambient levels could create different reactions at different times of day. After controlling for ambient noise in a multiple regression analysis, no significant differences were found between the ratings of single events obtained during the three time periods: morning, afternoon, and evenings.

  6. Collision avoidance for aircraft in abort landing

    Science.gov (United States)

    Mathwig, Jarret

    We study the collision avoidance between two aircraft flying in the same vertical plane: a host aircraft on a glide path and an intruder aircraft on a horizontal trajectory below that of the host aircraft and heading in the opposite direction. Assuming that the intruder aircraft is uncooperative, the host aircraft executes an optimal abort landing maneuver: it applies maximum thrust setting and maximum angle of attack lifting the flight path over the original path, thereby increasing the timewise minimum distance between the two aircraft and, in this way, avoiding the potential collision. In the presence of weak constraints on the aircraft and/or the environment, the angle of attack must be brought to the maximum value and kept there until the maximin point is reached. On the other hand, in the presence of strong constraints on the aircraft and the environment, desaturation of the angle of attack might have to take place before the maximin point is reached. This thesis includes four parts. In the first part, after an introduction and review of the available literature, we reformulate and solve the one-subarc Chebyshev maximin problem as a two-subarc Bolza-Pontryagin problem in which the avoidance and the recovery maneuvers are treated simultaneously. In the second part, we develop a guidance scheme (gamma guidance) capable of approximating the optimal trajectory in real time. In the third part, we present the algorithms employed to solve the one-subarc and two-subarc problems. In the fourth part, we decompose the two-subarc Bolza-Pontryagin problem into two one-subarc problems: the avoidance problem and the recovery problem, to be solved in sequence; remarkably, for problems where the ratio of total maneuver time to avoidance time is sufficiently large (≥5), this simplified procedure predicts accurately the location of the maximin point as well as the maximin distance.

  7. Aircraft control in wake vortex wind shear

    Science.gov (United States)

    Wold, Gregory R.

    1995-01-01

    In the past, there have been a number of fatal incidents attributable to wake vortex encounters, involving both general aviation and commercial aircraft. In fact, the wake vortex hazard is considered to be the single dominant safety issue determining the aircraft spacing requirements at airports. As the amount of air traffic increases, the number of dangerous encounters is likely only to increase. It is therefore imperative that a means be found to reduce the danger. That is the purpose of this research: to use nonlinear inverse dynamic (NID) control methods in the design of an aircraft control system which can improve the safety margin in a wake vortex encounter.

  8. Aircraft wake vortices in the atmosphere

    Science.gov (United States)

    Gerz, Thomas; Holzäpfel, Frank; Hofbauer, Thomas; Dörnbrack, Andreas; Frech, Michael

    The studies summarized here were motivated by the need to gain information (i) about the impact of aircraft emissions upon the atmosphere and the climate and (ii) about optimized separation distances between aircraft landing at an airport for possibly increasing its capacity. To this end, large-eddy simulations have been performed to learn about the behaviour of vortex wakes shed by cruising aircraft in the free atmosphere and in the atmospheric boundary layer close to the ground. Some results are best illustrated in animated form and may be found under http://www.pa.op.dlr.de/wirbelschleppe/WakeVortex.html.

  9. Computing Linear Mathematical Models Of Aircraft

    Science.gov (United States)

    Duke, Eugene L.; Antoniewicz, Robert F.; Krambeer, Keith D.

    1991-01-01

    Derivation and Definition of Linear Aircraft Model (LINEAR) computer program provides user with powerful, and flexible, standard, documented, and verified software tool for linearization of mathematical models of aerodynamics of aircraft. Intended for use in software tool to drive linear analysis of stability and design of control laws for aircraft. Capable of both extracting such linearized engine effects as net thrust, torque, and gyroscopic effects, and including these effects in linear model of system. Designed to provide easy selection of state, control, and observation variables used in particular model. Also provides flexibility of allowing alternate formulations of both state and observation equations. Written in FORTRAN.

  10. Sensibility and Subjectivity: Levinas’ Traumatic Subject

    Directory of Open Access Journals (Sweden)

    Rashmika Pandya

    2011-02-01

    Full Text Available The importance of Levinas’ notions of sensibility and subjectivity are evident in the revision of phenomenological method by current phenomenologists such as Jean-Luc Marion and Michel Henry. The criticisms of key tenants of classical phenomenology, intentionality and reduction, are of a particular note. However, there are problems with Levinas’ characterization of subjectivity as essentially sensible. In “Totality and Infinity” and “Otherwise than Being”, Levinas criticizes and recasts a traditional notion of subjectivity, particularly the notion of the subject as the first and foremost rational subject. The subject in Levinas’ works is characterized more by its sensibility and affectedness than by its capacity to reason or affect its world. Levinas ties rationality to economy and suggests an alternative notion of reason that leads to his analysis of the ethical relation as the face-to-face encounter. The ‘origin’ of the social relation is located not in our capacity to know but rather in a sensibility that is diametrically opposed to the reason understood as economy. I argue that the opposition in Levinas’ thought between reason and sensibility is problematic and essentially leads to a self-conflicted subject. In fact, it would seem that violence characterizes the subject’s self-relation and, thus, is also inscribed at the base of the social relation. Rather than overcoming a problematic tendency to dualistic thought in philosophy Levinas merely reverses traditional hierarchies of reason/emotion, subject/object and self/other. 

  11. Reversibility of stress-echo induced ST-segment depression by long-term oral n-3 PUFA supplementation in subjects with chest pain syndrome, normal wall motion at stress-echo and normal coronary angiogram

    Directory of Open Access Journals (Sweden)

    Ziacchi Vigilio

    2004-03-01

    Full Text Available Abstract Background Normal coronary arteries may coexist with abnormal coronary and systemic endothelial function in patients with chest pain. Recent work by the renowned Pisa echo-group elegantly suggests that isolated ST-segment depression during stress-echo (SE can be used as a marker of coronary endothelial dysfunction, in the absence of stress-inducible wall motion abnormalities and in the absence of angiographically-significant coronary artery disease (CAD. The long chain n-3 polyunsaturated fatty acids (PUFAs have been reported to possess several properties that may positively influence vascular function. The present study's hypothesis is that a 4 month-course of oral supplementation with n-3 PUFAs can reverse endothelial dysfunction. Methods Subjects were selected on the basis of the following criteria: 1 reported chest pain syndrome, 2 significant ST-segment depression during an otherwise normal SE, 3 absence of angiographically-significant CAD. Subjects underwent a 4-month course of oral supplementation with commercially available n-3 PUFA, 1 g once a day. Normalization of endothelial dysfunction was defined, at the end of the supplementation period, by the absence of significant ST-segment depression during repeat SE. We tested the aforementioned hypothesis in a very small series of consecutive subjects, with the intent to produce a hypothesis-generating study. Results Seven out of the total nine subjects enrolled (77.8% had normal ST-segment during repeat SE performed after the 4 month course of therapy. Conclusions A striking rate of reversion of SE-induced ST-segment depression after oral n-3 PUFAs suggests reversion of coronary endothelial dysfunction; nonetheless these data need to be validated in larger, placebo-controlled studies.

  12. 8 CFR 234.3 - Aircraft; how considered.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Aircraft; how considered. 234.3 Section 234... PORTS OF ENTRY FOR ALIENS ARRIVING BY CIVIL AIRCRAFT § 234.3 Aircraft; how considered. Except as otherwise specifically provided in the Immigration and Nationality Act and this chapter, aircraft arriving...

  13. 14 CFR 49.11 - FAA Aircraft Registry.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false FAA Aircraft Registry. 49.11 Section 49.11 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT RECORDING OF AIRCRAFT TITLES AND SECURITY DOCUMENTS General § 49.11 FAA Aircraft Registry. To be eligible for recording...

  14. 14 CFR 375.11 - Other foreign civil aircraft.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Other foreign civil aircraft. 375.11... PROCEEDINGS) SPECIAL REGULATIONS NAVIGATION OF FOREIGN CIVIL AIRCRAFT WITHIN THE UNITED STATES Authorization § 375.11 Other foreign civil aircraft. A foreign civil aircraft other than those referred to in § 375.10...

  15. 19 CFR 122.86 - Substitution of aircraft.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Substitution of aircraft. 122.86 Section 122.86... Substitution of aircraft. (a) Application. The residue cargo procedure applies when an airline must substitute aircraft to reach a destination due to weather conditions or operational factors which prevent an aircraft...

  16. 42 CFR 71.44 - Disinsection of aircraft.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Disinsection of aircraft. 71.44 Section 71.44... Disinsection of aircraft. (a) The Director may require disinsection of an aircraft if it has left a foreign area that is infected with insect-borne communicable disease and the aircraft is suspected of harboring...

  17. 14 CFR 65.67 - Aircraft dispatcher certification courses: Personnel.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aircraft dispatcher certification courses... TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Aircraft Dispatchers § 65.67 Aircraft dispatcher certification courses: Personnel. (a) Each applicant for an aircraft...

  18. 14 CFR 47.19 - FAA Aircraft Registry.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false FAA Aircraft Registry. 47.19 Section 47.19 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRCRAFT REGISTRATION General § 47.19 FAA Aircraft Registry. Each application, request, notification, or other...

  19. 177 airport acoustics: aircraft ise ibution and modelling of some ...

    African Journals Online (AJOL)

    Keywords :jlircraft noise, aircraft parameters and enoironmenta[ noise climate. 1. Introduction. Since the early 1950s, the number of transportation aircraft has increased tremendously (EPA, 1971). The increase, especially of general aviation aircraft, jet aircraft and helicopters, has had significant impart on our environment, ...

  20. 77 FR 42455 - Airworthiness Directives; Piper Aircraft, Inc. Airplanes

    Science.gov (United States)

    2012-07-19

    ... Federal Aviation Administration 14 CFR Part 39 RIN 2120-AA64 Airworthiness Directives; Piper Aircraft, Inc... directive (AD) for all Piper Aircraft, Inc. (type certificate previously held by The New Piper Aircraft Inc... receive about this proposed AD. Discussion Three forced landings of Piper Aircraft, Inc. Model PA-18...

  1. Short-term Acipimox decreases the ability of plasma from Type 2 diabetic patients and healthy subjects to stimulate cellular cholesterol efflux : a potentially adverse effect on reverse cholesterol transport

    NARCIS (Netherlands)

    Dullaart, RPF; van Tol, A

    Aims To evaluate the effect of short-term administration of the anti-lipolytic agent, Acipimox, on the ability of plasma to stimulate cellular cholesterol removal, which represents one of the first steps in the anti-atherogenic process of reverse cholesterol transport. Methods Eight male Type 2

  2. Short-term Acipimox decreases the ability of plasma from type 2 diabetic patients and healthy subjects to stimulate cellular cholesterol efflux: A potentially adverse effect on reverse cholesterol transport

    NARCIS (Netherlands)

    R.P.F. Dullaart (Robin); A. van Tol (Arie)

    2001-01-01

    textabstractAims: To evaluate the effect of short-term administration of the anti-lipolytic agent, Acipimox, on the ability of plasma to stimulate cellular cholesterol removal, which represents one of the first steps in the anti-atherogenic process of reverse cholesterol transport. Methods: Eight

  3. Skin collagen glycation, glycoxidation, and crosslinking are lower in subjects with long-term intensive versus conventional therapy of type 1 diabetes - Relevance of glycated collagen products versus HbA(1c) as markers of diabetic complications

    NARCIS (Netherlands)

    Monnier, VM; Bautista, O; Kenny, D; Sell, DR; Fogarty, J; Dahms, W; Cleary, PA; Lachin, J; Genuth, S

    The relationships between long-term intensive control of glycemia and indicators of skin collagen glycation (furosine), glycoxidation (pentosidine and N-epsilon-[carboxymethyl]-lysine [CML]), and crosslinking (acid and pepsin solubility) were examined in 216 patients with type 1 diabetes from the

  4. Kinematic response of the spine during simulated aircraft ejections.

    Science.gov (United States)

    Damon, Andrew M; Lessley, David J; Salzar, Robert S; Bass, Cameron R; Shen, Francis H; Paskoff, Glenn R; Shender, Barry S

    2010-05-01

    Military aviators are susceptible to spinal injuries during high-speed ejection scenarios. These injuries commonly arise as a result of strains induced by extreme flexion or compression of the spinal column. This study characterizes the vertebral motion of two postmortem human surrogates (PMHS) during a simulated catapult phase of ejection on a horizontal decelerator sled. During testing, the PMHS were restrained supinely to a mock ejection seat and subjected to a horizontal deceleration profile directed along the local z-axis. Two midsized males (175.3 cm, 77.1 kg; 185.4 cm, 72.6 kg) were tested. High-rate motion capture equipment was used to measure the three-dimensional displacement of the head, vertebrae, and pelvis during the ejection event. The two PMHS showed generally similar kinematic motion. Head injury criterion (HIC) results were well below injury threshold levels for both specimens. The specimens both showed compression of the spine, with a reduction in length of 23.9 mm and 45.7 mm. Post-test autopsies revealed fractures in the C5, T1, and L1 vertebrae. This paper provides an analysis of spinal motion during an aircraft ejection.The injuries observed in the test subjects were consistent with those seen in epidemiological studies. Future studies should examine the effects of gender, muscle tensing, out-of-position (of head from neutral position) occupants, and external forces (e.g., windblast) on spinal kinematics during aircraft ejection.

  5. Hearing status among aircraft maintenance personnel in a commercial airline company

    Directory of Open Access Journals (Sweden)

    Greta Smedje

    2011-01-01

    Full Text Available The aim was to study subjective and objective hearing loss in a population of aircraft maintenance workers and identify predictors. A total of 327 aircraft maintenance personnel answered a self-administered work environment questionnaire (response rate 76% and underwent audiometric test. The mean values for the hearing threshold at 3, 4, and 6 kHz for the ear with the most hearing loss were compared with a Swedish population database of persons not occupationally exposed to noise. Equivalent noise exposure during a working day was measured. Relationships between subjective and objective hearing loss and possible predictors (age, years of employment, self-reported exposure to solvents, blood pressure, and psycho-social factors were analyzed by multiple logistic regression. At younger ages (<40 years, aircraft maintenance workers had higher hearing thresholds (1-3 dB compared to the reference group, but such a difference was not found in older employees. Relationships were found between age and objective hearing loss, and between exposure to solvents and reported subjective hearing loss. Equivalent noise exposure during working days were 70-91 dB(A with a maximal noise level of 119 dB(A. Aircraft maintenance workers are exposed to equivalent noise levels above the Swedish occupational standard, including some very high peak exposures. Younger employees have a higher age-matched hearing threshold level compared with a reference group. Thus, there is a need for further preventive measures.

  6. Hearing status among aircraft maintenance personnel in a commercial airline company.

    Science.gov (United States)

    Smedje, Greta; Lunden, Maria; Gärtner, Lotta; Lundgren, Håkan; Lindgren, Torsten

    2011-01-01

    The aim was to study subjective and objective hearing loss in a population of aircraft maintenance workers and identify predictors. A total of 327 aircraft maintenance personnel answered a self-administered work environment questionnaire (response rate 76%) and underwent audiometric test. The mean values for the hearing threshold at 3, 4, and 6 kHz for the ear with the most hearing loss were compared with a Swedish population database of persons not occupationally exposed to noise. Equivalent noise exposure during a working day was measured. Relationships between subjective and objective hearing loss and possible predictors (age, years of employment, self-reported exposure to solvents, blood pressure, and psycho-social factors) were analyzed by multiple logistic regression. At younger ages (<40 years), aircraft maintenance workers had higher hearing thresholds (1-3 dB) compared to the reference group, but such a difference was not found in older employees. Relationships were found between age and objective hearing loss, and between exposure to solvents and reported subjective hearing loss. Equivalent noise exposure during working days were 70-91 dB(A) with a maximal noise level of 119 dB(A). Aircraft maintenance workers are exposed to equivalent noise levels above the Swedish occupational standard, including some very high peak exposures. Younger employees have a higher age-matched hearing threshold level compared with a reference group. Thus, there is a need for further preventive measures.

  7. Impact of Advanced Propeller Technology on Aircraft/Mission Characteristics of Several General Aviation Aircraft

    Science.gov (United States)

    Keiter, I. D.

    1982-01-01

    Studies of several General Aviation aircraft indicated that the application of advanced technologies to General Aviation propellers can reduce fuel consumption in future aircraft by a significant amount. Propeller blade weight reductions achieved through the use of composites, propeller efficiency and noise improvements achieved through the use of advanced concepts and improved propeller analytical design methods result in aircraft with lower operating cost, acquisition cost and gross weight.

  8. Comparison of alternate fuels for aircraft. [liquid hydrogen, liquid methane, and synthetic aviation kerosene

    Science.gov (United States)

    Witcofski, R. D.

    1979-01-01

    Liquid hydrogen, liquid methane, and synthetic aviation kerosene were assessed as alternate fuels for aircraft in terms of cost, capital requirements, and energy resource utilization. Fuel transmission and airport storage and distribution facilities are considered. Environmental emissions and safety aspects of fuel selection are discussed and detailed descriptions of various fuel production and liquefaction processes are given. Technological deficiencies are identified.

  9. Potential uses of small unmanned aircraft systems (UAS) in weed research

    DEFF Research Database (Denmark)

    Rasmussen, Jesper; Nielsen, Jon; Garcia Ruiz, Francisco Jose

    2013-01-01

    Small unmanned aerial systems (UAS) with cameras have not been adopted in weed research, but offer low-cost sensing with high flexibility in terms of spatial resolution. A small rotary-wing UAS was tested as part of a search for an inexpensive, user-friendly and reliable aircraft for practical...

  10. Estimation of required number of aircraft resource spare parts based on statistical modelling

    Directory of Open Access Journals (Sweden)

    E. D. Gerasimova

    2015-01-01

    Full Text Available The article describes a method of statistical modelling form the required amount of spare resource by the criterion of performance assurance of aircraft functionale systems for a long term operation. The calculations and the results of the statistical modelling are given.

  11. Aircraft Test & Evaluation Facility (Hush House)

    Data.gov (United States)

    Federal Laboratory Consortium — The Aircraft Test and Evaluation Facility (ATEF), or Hush House, is a noise-abated ground test sub-facility. The facility's controlled environment provides 24-hour...

  12. Airframe Certification Methods for Unmanned Aircraft

    National Research Council Canada - National Science Library

    Saff, Charles R

    2006-01-01

    The application of conventional structural certification methods to unmanned aircraft can lead to unacceptably long development times and costs that are out of line with the development costs for the airframe...

  13. Aircraft Trajectory Optimization Using Parametric Optimization Theory

    OpenAIRE

    Valenzuela Romero, Alfonso

    2012-01-01

    In this thesis, a study of the optimization of aircraft trajectories using parametric optimization theory is presented. To that end, an approach based on the use of predefined trajectory patterns and parametric optimization is proposed. The trajectory pat

  14. Design of heavy lift cargo aircraft

    Data.gov (United States)

    National Aeronautics and Space Administration — This is the bird of the skies of the future. The heavy lift cargo aircraft which is currently being developed by me has twice the payload capacity of an Antonov...

  15. PLANNING OF TRAINING AIRCRAFT FLIGHT HOURS

    Directory of Open Access Journals (Sweden)

    Visnja Vojvodić Rosenzweig

    2010-12-01

    Full Text Available Maintenance of the training aircraft causes downtime of operations and thereby reduces the operational availability, which is crucial for flight planning in a training organisation. Manual daily planning within the fleet delivers suboptimal results and often causes discontinued flight of several aircraft that have to be maintained at the same time. Optimal maintenance schedule of training aircraft can be obtained by a sliding scale method. This paper presents a mathematical model of the sliding scale formulated by a mixed integer linear problem. Allocation of flight hours is optimised by using AMPL programming language, assuring that a sufficient number of aircraft are always available for training. The model can be used by a flight dispatch department in a training organisation as a basis for optimised planning and reduction of maintenance downtime.

  16. Aircraft Nodal Data Acquisition System (ANDAS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Development of an Aircraft Nodal Data Acquisition System (ANDAS) is proposed. The proposed methodology employs the development of a very thin (135m) hybrid...

  17. Aircraft Nodal Data Acquisition System (ANDAS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Development of an Aircraft Nodal Data Acquisition System (ANDAS) based upon the short haul Zigbee networking standard is proposed. It employs a very thin (135 um)...

  18. Children restraint systems for civil aircraft.

    Science.gov (United States)

    1978-03-01

    Child restraint systems have been developed to provide protection to children involved in automobile crashes. These systems are not yet approved for use in civil aircraft. Six typical systems were exposed to controlled impacts on a test sled to simul...

  19. Child restraint systems for civil aircraft.

    Science.gov (United States)

    1978-03-01

    Child restraint systems have been developed to provide protection to children involved in automobile crashes. These systems are not yet approved for use in civil aircraft. Six typical systems were exposed to controlled impacts on a test sled to simul...

  20. Unmanned Aircraft Systems - Digital Elevation Model

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The USGS National Unmanned Aircraft Systems (UAS) Project Office utilizes UAS technology for collecting remote sensing data on a local scale. Typical UAS projects...

  1. Unmanned Aircraft Systems - Point Cloud Data

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The USGS National Unmanned Aircraft Systems (UAS) Project Office utilizes UAS technology for collecting remote sensing data on a local scale. Typical UAS projects...

  2. Finite Element Aircraft Simulation of Turbulence

    Science.gov (United States)

    1997-02-01

    A Simulation of Rotor Blade Element Turbulence (SORBET) model has been : developed for realtime aircraft simulation that accommodates stochastic : turbulence and distributed discrete gusts as a function of the terrain. This : model is applicable to c...

  3. Emerging nondestructive inspection methods for aging aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Beattie, A; Dahlke, L; Gieske, J [and others

    1994-01-01

    This report identifies and describes emerging nondestructive inspection (NDI) methods that can potentially be used to inspect commercial transport and commuter aircraft for structural damage. The nine categories of emerging NDI techniques are: acoustic emission, x-ray computed tomography, backscatter radiation, reverse geometry x-ray, advanced electromagnetics, including magnetooptic imaging and advanced eddy current techniques, coherent optics, advanced ultrasonics, advanced visual, and infrared thermography. The physical principles, generalized performance characteristics, and typical applications associated with each method are described. In addition, aircraft inspection applications are discussed along with the associated technical considerations. Finally, the status of each technique is presented, with a discussion on when it may be available for use in actual aircraft maintenance programs. It should be noted that this is a companion document to DOT/FAA/CT-91/5, Current Nondestructive Inspection Methods for Aging Aircraft.

  4. Spring 2008 Industry Study: Aircraft Industry

    National Research Council Canada - National Science Library

    Smith, John; Dedecker, Craig; Doerer, Robert; Dols, Jonathan; Ekwall, Bengt; Heck, Mark; Jungco, Rolando; Koch, David; Lolley, James; Matyi, Kyle; McCaffrey, Terrance; Provost, Carla; Snyder, Daniel; Szucs, Jozsef; Truhn, Harry; Tyler, J. R

    2008-01-01

    .... With the exception of the relatively less mature unmanned aircraft systems sector, significant changes to the number and identity of competing firms are not likely in the next few years, although...

  5. Unmanned aircraft systems for transportation decision support.

    Science.gov (United States)

    2016-11-30

    Our nation relies on accurate geospatial information to map, measure, and monitor transportation infrastructure and the surrounding landscapes. This project focused on the application of Unmanned Aircraft systems (UAS) as a novel tool for improving e...

  6. Unmanned Aircraft Systems Roadmap 2005-2030

    Science.gov (United States)

    2005-01-01

    This document presents the Department of Defense's (DoD) roadmap for developing and employing unmanned aircraft systems over the next 25 years (2005 to 2030). It describes the missions identified by theater warfighters to which systems could be appli...

  7. Thermal Management System for Superconducting Aircraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aircraft powered by hydrogen power plants or gas turbines driving electric generators connected to distributed electric motors for propulsion have the potential to...

  8. Safety of Cargo Aircraft Handling Procedure

    Directory of Open Access Journals (Sweden)

    Daniel Hlavatý

    2017-07-01

    Full Text Available The aim of this paper is to get acquainted with the ways how to improve the safety management system during cargo aircraft handling. The first chapter is dedicated to general information about air cargo transportation. This includes the history or types of cargo aircraft handling, but also the means of handling. The second part is focused on detailed description of cargo aircraft handling, including a description of activities that are performed before and after handling. The following part of this paper covers a theoretical interpretation of safety, safety indicators and legislative provisions related to the safety of cargo aircraft handling. The fourth part of this paper analyzes the fault trees of events which might occur during handling. The factors found by this analysis are compared with safety reports of FedEx. Based on the comparison, there is a proposal on how to improve the safety management in this transportation company.

  9. Modular Electric Propulsion Test Bed Aircraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A hybrid electric aircraft simulation system and test bed is proposed to provide a dedicated development environment for the rigorous study and advancement of hybrid...

  10. AIRCRAFT CONFLICTS RESOLUTION BY COURSE MANEUVERING

    Directory of Open Access Journals (Sweden)

    В. Харченко

    2011-02-01

    Full Text Available Enhancement of requirements for air traffic efficiency at increasing of flights intensity determines the necessity of development of new optimization methods for aircraft conflict resolutions. The statement of problem of optimal conflict resolutions at Cooperative Air Traffic Management was done. The method for optimal aircraft conflict  resolution by course maneuvering has been  developed. The method using dynamic programming provides planning of aircraft conflict-free trajectory with minimum length. The decomposition of conflict resolution process on phases and stages, definition of states, controls and recursive  equations for generation of optimal course control program were done. Computer modeling of aircraft conflict resolution by developed method was done

  11. Electrically conductive carbon fibre-reinforced composite for aircraft lightning strike protection

    Science.gov (United States)

    Katunin, Andrzej; Krukiewicz, Katarzyna; Turczyn, Roman; Sul, Przemysław; Bilewicz, Marcin

    2017-05-01

    Aircraft elements, especially elements of exterior fuselage, are subjected to damage caused by lightning strikes. Due to the fact that these elements are manufactured from polymeric composites in modern aircraft, and thus, they cannot conduct electrical charges, the lightning strikes cause burnouts in composite structures. Therefore, the effective lightning strike protection for such structures is highly desired. The solution presented in this paper is based on application of organic conductive fillers in the form of intrinsically conducting polymers and carbon fabric in order to ensure electrical conductivity of whole composite and simultaneously retain superior mechanical properties. The presented studies cover synthesis and manufacturing of the electrically conductive composite as well as its characterization with respect to mechanical and electrical properties. The performed studies indicate that the proposed material can be potentially considered as a constructional material for aircraft industry, which characterizes by good operational properties and low cost of manufacturing with respect to current lightning strike protection materials solutions.

  12. Orthodontic Treatment and Maxillary Anterior Segmental Distraction Osteogenesis of a Subject with Williams–Beuren Syndrome and Isolated Cleft Palate: A Long-Term Follow-Up from the Age of 5 to 24 Years

    Directory of Open Access Journals (Sweden)

    Tetsutaro Yamaguchi

    2017-01-01

    Full Text Available Williams–Beuren syndrome (WBS is a rare multisystem disorder caused by a hemizygous deletion of the elastin gene on chromosome 7q11.23. WBS patients have characteristic skeletal features and dental anomalies accompanied by mental retardation, a friendly outgoing personality, and mild to moderate intellectual disability or learning problems. In this case report, we present the combined orthodontic and surgical treatment of a WBS patient with an isolated cleft palate through a long-term follow-up from the age of 5 to 24 years. During the period of active treatment, comprehensive orthodontic treatment combined with maxillary anterior segmental distraction osteogenesis and prosthetic treatment using dental implants were effective in dramatically improving the patient’s malocclusion. The patient’s mental abilities and the cooperation shown by the patient and her family were crucial for the success of this complex and long-term treatment course.

  13. Subjective loudness of "minimized" sonic boom waveforms.

    Science.gov (United States)

    Niedzwiecki, A; Ribner, H S

    1978-12-01

    For very long supersonic aircraft the "midfield" sonic boom signature may not have evolved fully into an N wave at ground level. Thus in current boom minimization techniques the shape of the aircraft may be tailored to optimize this midfield wave form for reduced subjective loudness. The present investigation tests a family of "flat-top" waveforms cited by Darden: all but one have a front shock height (deltapSH) less than the peak amplitude (deltapMAX). For equal subjective loudness, "flat top" vs N wave (peak overpressure deltapN), the peak amplitude of the "flat top" signature was found to be substantially higher than that of the N wave; thus for equal peak amplitude the "flat-top" signature was quieter. The results for equal loudness were well fitted by an emperical law deltapSH + 0.11deltapMAX = deltapN; the equivalence shows how the front shock amplitude (deltapSH) dominates the loudness. All this was found compatible with predictions by the method of Johnson and Robinson.

  14. Conceptual design and optimization methodology for box wing aircraft

    OpenAIRE

    Jemitola, Paul Olugbeji

    2012-01-01

    A conceptual design optimization methodology was developed for a medium range box wing aircraft. A baseline conventional cantilever wing aircraft designed for the same mis- sion and payload was also optimized alongside a baseline box wing aircraft. An empirical formula for the mass estimation of the fore and aft wings of the box wing aircraft was derived by relating conventional cantilever wings to box wing aircraft wings. The results indicate that the fore and aft wings would ...

  15. Methods for Aircraft State and Parameter Identification

    Science.gov (United States)

    1975-05-01

    IFIP Conference on Optimization Techniques. Rome, Italy, May 1973. 3. Mehra, Raman K., and Stepner, David E.: "Maximm Likelihood Identification and...Aircraft. Rept. 1356, Res.. Dept., Cessan Aircraft Co., Key 1957. 10. Stepner, David E., and Mehra, Raman K.: ?Kaximum Likelihood Identification and...the position input signal ass mostly dus to talmtry noise. which mae metly 1 percent of full scale. The eccelerometer signal noias , mialy due to

  16. Aircraft Wake Vortex Deformation in Turbulent Atmosphere

    OpenAIRE

    Hennemann, Ingo; Holzaepfel, Frank

    2007-01-01

    Large-scale distortion of aircraft wake vortices appears to play a crucial role for aircraft safety during approach and landing. Vortex distortion is investigated based on large eddy simulations of wake vortex evolution in a turbulent atmosphere. A vortex identification method is developed that can be adapted to the vortex scales of interest. Based on the identified vortex center tracks, a statistics of vortex curvature radii is established. This statistics constitutes the basis for understan...

  17. Energy-Absorbing Passenger Seat for Aircraft

    Science.gov (United States)

    Eichelberger, C. P.; Alfaro-Bou, E.; Fasanella, E. L.

    1987-01-01

    Development of energy-absorbing passenger seat, designed to minimize injury in commercial-aircraft crash, part of joint FAA/NASA controlledimpact flight test of transport-category commercial aircraft. Modified seat mechanism collapses under heavy load to absorb impact energy and thereby protect passenger. Results of simulation tests indicate probability of passenger survival high. Proposed seat mechanism mitigates passenger injuries by reducing impact forces in crash.

  18. Enabling alternate fuels for commercial aircraft

    OpenAIRE

    Daggett, D.

    2010-01-01

    The following reports on the past four years of work to examine the feasibility, sustainability and economic viability of developing a renewable, greenhouse-gas-neutral, liquid biofuel for commercial aircraft. The sharp increase in environmental concerns, such as global warming, as well as the volatile price fluctuations of fossil fuels, has ignited a search for alternative transportation fuels. However, commercial aircraft can not use present alternative fuels that are designed for ground...

  19. Aircraft Survivability. Susceptibility Reduction. Fall 2010

    Science.gov (United States)

    2010-01-01

    importance of what we do, and showcased the joint nature of our organization. CDR Fehrle and LT John responded to the scene immediately to begin the...Eye-One Photo SG” spectro-photometer (Gretag Macbeth GRET-0366), which provides 10nm resolution across the 380-730nm spectral range. The paints...Approach The short timelines, prevalence, and portable nature of the aircraft threats described lead us to a change in the paradigm of aircraft

  20. Distributed radar sensors for aircraft detection

    Science.gov (United States)

    Canavan, G. H.

    1991-04-01

    Radars suitable for aircraft detection could be deployed on singlet space-based interceptor (SBI) platforms. They could operate at short ranges and still achieve useful search rates. Powers are modest and insensitive to frequency; the dominant costs are the pulsers and phased-array elements. A fundamental simplification results from mounting the radar on the life jacket rather than the SBI. Many satellites could be processed to derive aircraft trajectories sufficiently accurate for the commitment of fighters or defensive missiles.