39,642 research outputs found

    Leak test system

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    System for quantitative determination of leak rates in large pressurized compartments is described. Method uses pressure reference cylinder placed in thermal contact with internal environment of compartment. Construction of equipment and details of operational procedure are reported. Illustration of equipment is included

    Summary of all cycle II.5 shear and boundary layer measurements, aerodynamics

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    The two measurement systems were used to measure mean velocity and velocity, mass flux, and total temperature fluctuations in the turbulent boundary on the fuselage of a KC-135 aircraft. The boundary layer thickness ranged between about 20 and 30 cm for the range of flight Mach numbers from about 0.25 to 0.85 and Reynolds numbers between 3 and 6 x 10 to the 6th power/m. The adaptation of each system for use in airborne applications is discussed. The data obtained from each system are given and compared with each other and they indicate that the two systems represent viable ones for use in future airborne turbulence experiments

    The use of honey in healing a recalcitrant wound following surgical treatment of hidradenitis suppurativa

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    Ancient civilizations used honey to heal wounds. Despite the rediscovery of honey by modern physicians1 its use in conventional medicine, unlike in complementary medicine, remains limited. Much anecdotal evidence, some clinical observations, some animal models and some randomised controlled trials support the efficacy of honey in managing wounds2,3 , but few detailed descriptions of the use of honey in healing difficult surgical wounds have previously been published

    The LHC di-photon excess and Gauge Coupling Unification in Extra ZZ^\prime Heterotic-String Derived Models

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    The di-photon excess observed at the LHC can be explained as a Standard Model singlet that is produced and decays by heavy vector-like colour triplets and electroweak doublets in one-loop diagrams. The characteristics of the required spectrum are well motivated in heterotic-string constructions that allow for a light ZZ^\prime. Anomaly cancellation of the U(1)ZU(1)_{Z^\prime} symmetry requires the existence of the Standard Model singlet and vector-like states in the vicinity of the U(1)ZU(1)_{Z^\prime} breaking scale. In this paper we show that the agreement with the gauge coupling data at one-loop is identical to the case of the Minimal Supersymmetric Standard Model, owing to cancellations between the additional states. We further show that effects arising from heavy thresholds may push the supersymmetric spectrum beyond the reach of the LHC, while maintaining the agreement with the gauge coupling data. We show that the string inspired model can indeed account for the observed signal and discuss the feasibility of obtaining viable scalar mass spectrum.Comment: 26 pages. 11 figures. Published versio

    Evidence of State-Level Variability in the Economic and Demographic Well-Being of People with Disabilities in India

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    Among countries with comparable levels of income, India has one of the more progressive disability policy frameworks; however, people with disabilities in India are subject to multiple disadvantages. This paper focuses on state-level variations in outcomes for people with disabilities to provide one explanation for the stark contrast between the liberal laws on paper and the challenges faced by people with disabilities in practice. Using a random coefficients model that allows for state-level differences, we find that households with members with disabilities have 4.2 percent lower marriage rates, monthly per capita expenditure that is lower by 176 Indian Rupees (19 percent of overall average per capita expenditure), and about a 5 percent lower level of completed formal schooling as compared to households without disabled individuals. Tests of parameter constancy across states are almost uniformly rejected indicating the presence of substantial state-level heterogeneity across all models in the outcomes examined.disability, India, economic well-being, state variations, people with disabilities

    High Accuracy Fuel Flowmeter, Phase 1

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    Technology related to aircraft fuel mass - flowmeters was reviewed to determine what flowmeter types could provide 0.25%-of-point accuracy over a 50 to one range in flowrates. Three types were selected and were further analyzed to determine what problem areas prevented them from meeting the high accuracy requirement, and what the further development needs were for each. A dual-turbine volumetric flowmeter with densi-viscometer and microprocessor compensation was selected for its relative simplicity and fast response time. An angular momentum type with a motor-driven, spring-restrained turbine and viscosity shroud was selected for its direct mass-flow output. This concept also employed a turbine for fast response and a microcomputer for accurate viscosity compensation. The third concept employed a vortex precession volumetric flowmeter and was selected for its unobtrusive design. Like the turbine flowmeter, it uses a densi-viscometer and microprocessor for density correction and accurate viscosity compensation

    A fiber-optic current sensor for aerospace applications

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    A robust, accurate, broad-band, alternating current sensor using fiber optics is being developed for space applications at power frequencies as high as 20 kHz. It can also be used in low and high voltage 60 Hz terrestrial power systems and in 400 Hz aircraft systems. It is intrinsically electromagnetic interference (EMI) immune and has the added benefit of excellent isolation. The sensor uses the Faraday effect in optical fiber and standard polarimetric measurements to sense electrical current. The primary component of the sensor is a specially treated coil of single-mode optical fiber, through which the current carrying conductor passes. Improved precision is accomplished by temperature compensation by means of signals from a novel fiber-optic temperature sensor embedded in the sensing head. The technology contained in the sensor is examined and the results of precision tests conducted at various temperatures within the wide operating range are given. The results of early EMI tests are also given

    Fiber-optic sensors for aerospace electrical measurements: An update

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    Fiber-optic sensors are being developed for electrical current, voltage, and power measurements in aerospace applications. These sensors are presently designed to cover ac frequencies from 60 Hz to 20 kHz. The current sensor, based on the Faraday effect in optical fiber, is in advanced development after some initial testing. Concentration is on packaging methods and ways to maintain consistent sensitivity with changes in temperature. The voltage sensor, utilizing the Pockels effect in a crystal, has excelled in temperature tests. This paper reports on the development of these sensors, the results of evaluation, improvements now in progress, and the future direction of the work

    Resilience, Acculturative Stress, and Family Norms Against Disclosure of Mental Health Problems Among Foreign-Born Filipino American Women

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    The present study explores the relationships between resilience, acculturative stress, and family norms against disclosure of mental health problems among foreign-born Filipino American women. The sample consisted of 159 foreign-born Filipino American women aged 18 years and above and residing in Las Vegas, Nevada, United States. Participants completed paper-and-pencil questionnaires. Results indicated high levels of resilience and moderate levels of acculturative stress. Findings also showed a significant negative correlation between resilience and acculturative stress, and a significant predictive effect of resilience on acculturative stress. We also found a significant negative relationship between resilience and family norms against disclosure of mental health problems but no significant mediating effect of resilience on the relationship between acculturative stress and family norms. This lack of significant findings related to the mediating effect of resilience on the relationship between acculturative stress and family norms against disclosure of mental illness may be due to the absence of theoretical models and research regarding the role of resilience in the context of acculturation among Filipino American women. Our findings imply the need to further explore underlying mechanisms that explain the relationships between resilience, acculturative stress, and family norms. The findings of the study also confirm the need to develop interventions and resources that ameliorate acculturative stress and promote an increase of the disclosure and reporting of mental health problems among Filipino American women
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