WorldWideScience

Sample records for space-qualified cryocoolers usml

  1. A space-qualified experiment integrating HTS digital circuits and small cryocoolers

    International Nuclear Information System (INIS)

    Silver, A.; Akerling, G.; Auten, R.

    1996-01-01

    High temperature superconductors (HTS) promise to achieve electrical performance superior to that of conventional electronics. For application in space systems, HTS systems must simultaneously achieve lower power, weight, and volume than conventional electronics, and meet stringent space qualification and reliability requirements. Most effort to date has focused on passive RF/microwave applications. However, incorporation of active microwave components such as amplifiers, mixers, and phase shifters, and on-board high data rate digital signal processing is limited by the power and weight of their spacecraft electronic and support modules. Absence of data on active HTS components will prevent their utilization in space. To validate the feasibility in space of HTS circuits and components based on Josephson junctions, one needs to demonstrate HTS circuits and critical supporting technologies, such as space-qualified packaging and interconnects, closed-cycle cryocooling, and interface electronics. This paper describes the packaging, performance, and space test plan of an integrated, space-qualified experimental package consisting of HTS Josephson junction circuits and all the supporting components for NRL's high temperature superconductor space experiment (HTSSE-II). Most of the technical challenges and approaches are equally applicable to passive and active RF/microwave and digital electronic components, and this experiment will provide valuable validation data

  2. Advanced cryocooler electronics for space

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, D.; Danial, A.; Godden, J.; Jackson, M.; McCuskey, J.; Valenzuela, P. [Northrop Grumman Space Technology, Redondo Beach, CA (United States); Davis, T. [Air Force Research Lab., Albuquerque, NM (United States)

    2004-08-01

    Space pulse-tube cryocoolers require electronics to control the cooling temperature and self-induced vibration. Other functions include engineering diagnostics, telemetry and safety protection of the unit against extreme environments and operational anomalies. The electronics must survive the harsh conditions of launch and orbit, and in some cases severe radiation environments for periods exceeding 10 years. A number of our current generation high reliability radiation hardened electronics units have been launched and others are in various stages of assembly or integration on a number of space flight programs. This paper describes the design features and performance of our next generation flight electronics designed for the STSS payloads. The electronics provides temperature control with better than +/-50 mK short-term stability. Self-induced vibration is controlled to low levels on all harmonics up to the 16th. A unique active power filter limits peak-to-peak reflected ripple current on the primary power bus to less than 3% of the average DC current. The 3 kg unit is capable of delivering 180 W continuous to NGST's high-efficiency cryocooler (HEC). (author)

  3. STS-50 USML-1, Onboard Photograph

    Science.gov (United States)

    1992-01-01

    The first United States Microgravity Laboratory (USML-1) was one of NASA's science and technology programs that provided scientists an opportunity to research various scientific investigations in a weightless environment inside the Spacelab module. It also provided demonstrations of new equipment to help prepare for advanced microgravity research and processing aboard the Space Station. The USML-1 flew in orbit for extended periods, providing greater opportunities for research in materials science, fluid dynamics, biotechnology (crystal growth), and combustion science. This is a close-up view of the Astroculture experiment rack in the middeck of the orbiter. The Astroculture experiment was to evaluate and find effective ways to supply nutrient solutions for optimizing plant growth and avoid releasing solutions into the crew quarters in microgravity. Since fluids behave differently in microgravity, plant watering systems that operate well on Earth do not function effectively in space. Plants can reduce the costs of providing food, oxygen, and pure water, as well as lower the costs of removing carbon dioxide in human space habitats. The USML-1 flew aboard the STS-50 mission on June 1992 and was managed by the Marshall Space Flight Center.

  4. 18th International Cryocooler Conference

    CERN Document Server

    Ross, Ronald G

    2014-01-01

    Cryocoolers 18 Cryocoolers 18 archives developments and performance measurements in the field of cryocoolers based on the contributions of leading international experts at the 18th International Cryocooler Conference that was held in Syracuse, New York, on June 9-12, 2014. The program of this conference lead to the 76 peer-reviewed papers that are published here. Over the years the International Cryocoolers Conference has become the preeminent worldwide conference for the presentation of the latest developments and test experiences with cryocoolers. The typical applications of this technology include cooling space and terrestrial infrared focal plane arrays, space x-ray detectors, medical applications, and a growing number of high-temperature superconductor applications.

  5. 17th International Cryocooler Conference

    CERN Document Server

    Ross, Ronald G

    2012-01-01

    Cryocoolers 17 archives developments and performance measurements in the field of cryocoolers based on the contributions of leading international experts at the 17th International Cryocooler Conference that was held in Los Angeles, California, on July 9-12, 2012. The program of this conference consisted of 94 papers; of these, 71 are published here. Over the years the International Cryocoolers Conference has become the preeminent worldwide conference for the presentation of the latest developments and test experiences with cryocoolers. The typical applications of this technology include cooling space and terrestrial infrared focal plane arrays, space x-ray detectors, medical applications, and a growing number of high-temperature superconductor applications.

  6. 16th International Cryocooler Conference

    CERN Document Server

    Ross, Ronald G

    2011-01-01

    Cryocoolers 16 archives developments and performance measurements in the field of cryocoolers based on the contributions of leading international experts at the 16th International Cryocooler Conference that was held in Atlanta, Georgia, on May 17-20, 2010. The program of this conference consisted of 116 papers; of these, 89 are published here. Over the years the International Cryocoolers Conference has become the preeminent worldwide conference for the presentation of the latest developments and test experiences with cryocoolers. The typical applications of this technology include cooling space and terrestrial infrared focal plane arrays, space x-ray detectors, medical applications, and a growing number of high-temperature superconductor applications.

  7. Cryocooler With Cold Compressor for Deep Space Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The unique built-in design features of the proposed mini pulse tube cryocooler avoid all thermal expansion issues enabling it to operate within a cold, 150 K...

  8. International Cryocooler Conference

    CERN Document Server

    Cryocoolers 13

    2005-01-01

    This is the 13th volume in the conference series. Over the years the International Cryocoolers Conference has become the preeminent worldwide conference for the presentation of the latest developments and test experiences with cryocoolers. The typical applications of this technology include cooling space and terrestrial infrared focal plane arrays, space x-ray detectors, medical applications, and a growing number of high-temperature super-capacitor applications.

  9. Modified-Collins cryocooler for zero-boiloff storage of cryogenic fuels in space

    Science.gov (United States)

    Hannon, Charles L.; Krass, Brady; Hogan, Jake; Brisson, John

    2012-06-01

    Future lunar and planetary explorations will require the storage of cryogenic propellants, particularly liquid oxygen (LOX) and liquid hydrogen (LH2), in low earth orbit (LEO) for periods of time ranging from days to months, and possibly longer. Without careful thermal management, significant quantities of stored liquid cryogens can be lost due to boil-off. Boil-off can be minimized by a variety of passive means including insulation, sun shades and passive radiational cooling. However, it has been shown that active cooling using space cryocoolers has the potential to result in Zero Boil-Off (ZBO) and the launch-mass savings using active cooling exceeds that of passive cooling of LOX for mission durations in LEO of less than 1 week, and for LH2 after about 2 months in LEO. Large-scale DC-flow cryogenic refrigeration systems operate at a fraction of the specific power levels required by small-scale AC-flow cryocoolers. The efficiency advantage of DC-flow cryogenic cycles motivates the current development of a cryocooler based on a modification of the Collins Cycle. The modified Collins cycle design employs piston type expanders that support high operating pressure ratios, electromagnetic valves that enable "floating pistons", and recuperative heat transfer. This paper will describe the design of a prototype Modified-Collins cryocooler for ZBO storage of cryogenic fuels in space.

  10. 8th International Cryocooler Conference

    CERN Document Server

    1995-01-01

    The last few years have witnessed a substantial maturing of long life Stirling-cycle cryocoolers built upon the heritage of the flexure-bearing cryocoolers from Oxford University, and have seen the emergence of mature pulse tube cryocoolers competing head-to-head with the Stirling cryocoolers. Hydrogen sorption cryocoolers, Gifford-McMahon cryocoolers with rare earth regenerators, and helium Joule-Thomson cryocoolers have also made tremendous progress in opening up applications in the 4 K to 10 K temperature range. Tactical Stirling cryocoolers, now commonplace in the defense industry, are finding application in a number of cost­ constrained commercial applications and space missions, and are achieving ever longer lives as they move to linear-drive, clearance-seal compressors. Building on this expanding availability of commercially viable cryocoolers, numerous new applications are being enabled; many of these involve infrared imaging systems, and high­ temperature superconductors in the medical and ...

  11. Tactical versus space cryocoolers: a comparision

    Science.gov (United States)

    Arts, R.; Mullié, J.; Leenders, H.; de Jonge, G.; Benschop, T.

    2017-05-01

    In recent years, several space cryocooler developments have been performed in parallel at Thales Cryogenics. On one end of the spectrum are research programmes such as the ESA-funded 30-50 K system developed in cooperation with CEA and Absolut System and the LPT6510 cooler developed in cooperation with Absolut System. On the other end of the spectrum are commercial designs adapted for space applications, such as the LPT9310 commercial coolers delivered for JPL's ECOSTRESS instrument and the LSF9199/30 SADA-compatible cooler delivered for various space programmes at Sofradir. In this paper, an overview is presented of the latest developments regarding these coolers. Initial performance results of the 30-50K cooler are discussed, pending developments for the LPT6510 cooler are presented, and the synergies between COTS and space are reviewed, such as design principles from space coolers being applied to an upgraded variant of the COTS LPT9310, as well as design principles from COTS coolers being applied to the LPT6510 for improved manufacturability.

  12. 10th International Cryocooler Conference

    CERN Document Server

    2002-01-01

    Cryocoolers 10 is the premier archival publication of the latest advances and performance of small cryogenic refrigerators designed to provide localized cooling for military, space, semi-conductor, medical, computing, and high-temperature superconductor cryogenic applications in the 2-200 K temperature range. Composed of papers written by leading engineers and scientists in the field, Cryocoolers 10 reports the most recent advances in cryocooler development, contains extensive performance test results and comparisons, and relates the latest experience in integrating cryocoolers into advanced applications.

  13. Space Stirling Cryocooler Contamination Lessons Learned and Recommended Control Procedures

    Science.gov (United States)

    Glaister, D. S.; Price, K.; Gully, W.; Castles, S.; Reilly, J.

    The most important characteristic of a space cryocooler is its reliability over a lifetime typically in excess of 7 years. While design improvements have reduced the probability of mechanical failure, the risk of internal contamination is still significant and has not been addressed in a consistent approach across the industry. A significant fraction of the endurance test and flight units have experienced some performance degradation related to internal contamination. The purpose of this paper is to describe and assess the contamination issues inside long life, space cryocoolers and to recommend procedures to minimize the probability of encountering contamination related failures and degradation. The paper covers the sources of contamination, the degradation and failure mechanisms, the theoretical and observed cryocooler sensitivity, and the recommended prevention procedures and their impact. We begin with a discussion of the contamination sources, both artificial and intrinsic. Next, the degradation and failure mechanisms are discussed in an attempt to arrive at a contaminant susceptibility, from which we can derive a contamination budget for the machine. This theoretical sensitivity is then compared with the observed sensitivity to illustrate the conservative nature of the assumed scenarios. A number of lessons learned on Raytheon, Ball, Air Force Research Laboratory, and NASA GSFC programs are shared to convey the practical aspects of the contamination problem. Then, the materials and processes required to meet the proposed budget are outlined. An attempt is made to present a survey of processes across industry.

  14. 15th International Cryocooler Conference

    CERN Document Server

    Ross, Ronald G

    2009-01-01

    This is the 15th volume in the conference series. Over the years the International Cryocooler Conference has become the preeminent worldwide conference for the presentation of the latest developments and test experiences with cryocoolers. The typical applications of this technology include cooling space and terrestrial infrared focal plane arrays, space x-ray detectors, medical applications, and a growing number of high-temperature superconductor applications.

  15. 14th International Cryocooler Conference

    CERN Document Server

    Ross, Ronald G

    2007-01-01

    This is the 14th volume in the conference series. Over the years the International Cryocoolers Conference has become the preeminent worldwide conference for the presentation of the latest developments and test experiences with cryocoolers. The typical applications of this technology include cooling space and terrestrial infrared focal plane arrays, space x-ray detectors, medical applications, and a growing number of high-temperature superconductor applications.

  16. Performance degradation of space Stirling cryocoolers due to gas contamination

    Science.gov (United States)

    Liu, Xin-guang; Wu, Yi-nong; Yang, Shao-hua; Zhang, Xiao-ming; Lu, Guo-hua; Zhang, Li

    2011-08-01

    With extensive application of infrared detective techniques, Stirling cryocoolers, used as an active cooling source, have been developed vigorously in China. After the cooler's cooling performance can satisfy the mission's request, its reliability level is crucial for its application. Among all the possible failure mechanisms, gas contamination has been found to be the most notorious cause of cooler's performance degradation by failure analyses. To analyze the characteristic of gas contamination, some experiments were designed and carried out to quantitatively analyze the relationship between failure and performance. Combined with the test results and the outgassing characteristic of non-metal materials in the cryocooler, a degradation model of cooling performance was given by T(t)=T0+A[1-exp(-t/B)] under some assumptions, where t is the running time, T is the Kelvin cooling temperature, and T0, A, B are model parameters, which can be given by the least square method. Here T0 is the fitting initial cooling temperature, A is the maximum range of performance degradation, and B is the time dependent constant of degradation. But the model parameters vary when a cryocooler is running at different cooling temperature ranges, or it is treated by different cleaning process. In order to verify the applicability of the degradation model, data fit analysis on eight groups of cooler's lifetime test was carried out. The final work indicated this model fit well with the performance degradation of space Stirling cryocoolers due to gas contamination and this model could be used to predict or evaluation the cooler's lifetime. Gaseous contamination will not arouse severe performance degradation until the contaminants accumulate to a certain amount, but it could be fatal when it works. So it is more serious to the coolers whose lifetime is more than 10,000 h. The measures taken to control or minimize its damage were discussed as well. To the long-life cryocooler, internal materials

  17. Calorimetric thermal-vacuum performance characterization of the BAe 80K space cryocooler

    International Nuclear Information System (INIS)

    Kotsubo, V.Y.; Johnson, D.L.; Ross, R.G. Jr.

    1992-01-01

    This paper on a comprehensive characterization program which is underway at JPL to generate test data on long-life, miniature Stirling-cycle cryocoolers for space application. The key focus of this paper is on the thermal performance of the British Aerospace (BAe) 80K split-Stirling-cycle cryocooler as measured in a unique calorimetric thermal-vacuum test chamber that accurately simulates the heat-transfer interfaces of space. Two separate cooling fluid loops provide precis individual control of the compressor and displacer heatsink temperatures. In addition, heatflow transducers enable calorimetric measurements of the heat rejected separately by the compressor and displacer. Cooler thermal performance has been mapped for coldtip temperatures ranging from below 45 K to above 150 K, for heat-sink temperatures ranging from 280 K to 320 K, and for a wide variety of operational variables including compressor-displacer phase, compressor-displacer stoke, drive frequency, and piston-displacer dc offset

  18. Air Force Research Laboratory Spacecraft Cryocooler Endurance Evaluation Facility Closing Report

    Science.gov (United States)

    Armstrong, J.; Martin, K. W.; Fraser, T.

    2015-12-01

    The Air Force Research Laboratory (AFRL) Spacecraft Component Thermal Research Group has been devoted to evaluating lifetime performance of space cryocooler technology for over twenty years. Long-life data is essential for confirming design lifetimes for space cryocoolers. Continuous operation in a simulated space environment is the only accepted method to test for degradation. AFRL has provided raw data and detailed evaluations to cryocooler developers for advancing the technology, correcting discovered deficiencies, and improving cryocooler designs. At AFRL, units of varying design and refrigeration cycles were instrumented in state-of-the-art experiment stands to provide spacelike conditions and were equipped with software data acquisition to track critical cryocooler operating parameters. This data allowed an assessment of the technology's ability to meet the desired lifetime and documented any long-term changes in performance. This paper will outline a final report of the various flight cryocoolers tested in our laboratory. The data summarized includes the seven cryocoolers tested during 2014-2015. These seven coolers have a combined total of 433,326 hours (49.5 years) of operation.

  19. Acoustic cryocooler

    International Nuclear Information System (INIS)

    Swift, G.W.; Martin, R.A.; Radebaugh, R.

    1990-01-01

    This patent describes an acoustic cryocooler with no moving parts is formed from a thermoacoustic driver (TAD) driving a pulse tube refrigerator (PTR) through a standing wave tube. Thermoacoustic elements in the TAD are spaced apart a distance effect to accommodate the increased thermal penetration length arising from the relatively low TAD operating frequency in the range of 15--60 Hz. At these low operating frequencies, a long tube is required to support the standing wave. The tube may be coiled to reduce the overall length of the cryocooler. One or two PTR's are located on the standing wave tube adjacent antinodes in the standing wave to be driven by the standing wave pressure oscillations. It is predicted that a heat input of 1000 W at 1000 K will maintain a cooling load of 5 W at 80 K

  20. Opposed piston linear compressor driven two-stage Stirling Cryocooler for cooling of IR sensors in space application

    Science.gov (United States)

    Bhojwani, Virendra; Inamdar, Asif; Lele, Mandar; Tendolkar, Mandar; Atrey, Milind; Bapat, Shridhar; Narayankhedkar, Kisan

    2017-04-01

    A two-stage Stirling Cryocooler has been developed and tested for cooling IR sensors in space application. The concept uses an opposed piston linear compressor to drive the two-stage Stirling expander. The configuration used a moving coil linear motor for the compressor as well as for the expander unit. Electrical phase difference of 80 degrees was maintained between the voltage waveforms supplied to the compressor motor and expander motor. The piston and displacer surface were coated with Rulon an anti-friction material to ensure oil less operation of the unit. The present article discusses analysis results, features of the cryocooler and experimental tests conducted on the developed unit. The two-stages of Cryo-cylinder and the expander units were manufactured from a single piece to ensure precise alignment between the two-stages. Flexure bearings were used to suspend the piston and displacer about its mean position. The objective of the work was to develop a two-stage Stirling cryocooler with 2 W at 120 K and 0.5 W at 60 K cooling capacity for the two-stages and input power of less than 120 W. The Cryocooler achieved a minimum temperature of 40.7 K at stage 2.

  1. Low-T, Low-Q Cryocoolers for Science Instruments

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of the planned research is to advance the current space science instruments through the development of light weight and low power cryocoolers. Currently,...

  2. Pressure cryocooling protein crystals

    Science.gov (United States)

    Kim, Chae Un [Ithaca, NY; Gruner, Sol M [Ithaca, NY

    2011-10-04

    Preparation of cryocooled protein crystal is provided by use of helium pressurizing and cryocooling to obtain cryocooled protein crystal allowing collection of high resolution data and by heavier noble gas (krypton or xenon) binding followed by helium pressurizing and cryocooling to obtain cryocooled protein crystal for collection of high resolution data and SAD phasing simultaneously. The helium pressurizing is carried out on crystal coated to prevent dehydration or on crystal grown in aqueous solution in a capillary.

  3. A novel method to hit the limit temperature of Stirling-type cryocooler

    Science.gov (United States)

    Wang, Jue; Pan, Changzhao; Zhang, Tong; Luo, Kaiqi; Zhou, Yuan; Wang, Junjie

    2018-02-01

    The Stirling-type cryocooler with its compact size and high efficiency is always expected to obtain its temperature limit of below 3 K. However, the pressure drop losses caused by high-frequency oscillation create large obstacles for this objective. This paper reports a novel thermal-driven Stirling-type cryocooler to obtain the lowest temperature of a Stirling-type cryocooler. The advantages of a thermal-driven cryocooler (Vuilleumier cryocooler) and pulse tube cryocooler are combined with a new type of cryocooler, called the Vuilleumier gas-coupling pulse tube hybrid cryocooler (VM-PT). A prototype of the VM-PT was recently developed and optimized in our laboratory. By using helium-4 as the working gas and magnetic regenerative materials (HoCu2 and Er3Ni), the lowest temperature of 2.5 K was obtained, which can be regarded as an important breakthrough for the Stirling-type cryocooler to achieve its limit temperature of below 3 K. It can supply >30 mW cooling power at 4.2 K and >500 mW cooling power at 20 K simultaneously. Theoretically, it is feasible to use this VM-PT for cooling the superconducting devices in space applications.

  4. Outgas analysis of mechanical cryocoolers for long lifetime

    Science.gov (United States)

    Sato, Yoichi; Shinozaki, Keisuke; Sawada, Kenichiro; Sugita, Hiroyuki; Mitsuda, Kazuhisa; Yamasaki, Noriko Y.; Nakagawa, Takao; Tsunematsu, Shoji; Otsuka, Kiyomi; Kanao, Kenichi; Yoshida, Seiji; Narasaki, Katsuhiro

    2017-12-01

    Mechanical cryocoolers for space applications are required to have high reliability to achieve long-term operation in orbit. ASTRO-H (Hitomi), the 6th Japanese X-ray astronomy mission, has a major scientific instrument onboard-the Soft X-ray Spectrometer (SXS) with several 20K-class two-stage Stirling (2ST) coolers and a 4K-class Joule Thomson (JT) cooler, which must operate for 3 years to ensure the lifetime of liquid helium as a cryogen for cooling of its detectors [1,2]. Other astronomical missions such as SPICA [3,4], LiteBIRD [5], and Athena [6] also have top requirements for these mechanical cryocoolers, including a 1K-class JT cooler to be operated for more than 3-5 years with no cryogen system. The reliability and lifetime of mechanical cryocoolers are generally understood to depend on (1) mechanical wear of the piston seal and valve seal, and (2) He working gas contaminated by impurity outgases, mainly H2O and CO2 released from the materials in the components of the cryocoolers. The second factor could be critical relative to causing blockage in the JT heat exchanger plumbing and the JT orifice or resulting in blockage in the Stirling regenerator and thereby degrading its performance. Thus, reducing the potential for outgassing in the cryocooler design and fabrication process, and predicting the total amount of outgases in the cryocooler are very important to ensure cryocooler lifetime and cooling performance in orbit. This paper investigates the outgas analysis of the 2ST and the 1K/4K-JT coolers for achieving a long lifetime. First, gas analysis was conducted for the materials and components of the mechanical cryocoolers, focusing on non-metallic materials as impurity gas sources. Then gas analysis of the mechanical wear effect of the piston seal materials and linear ball bearings was investigated. Finally, outgassing from a fully assembled cryocooler was measured to evaluate whether the outgas reduction process works properly to meet the requirement

  5. A free-piston Stirling cryocooler using metal diaphragms

    Science.gov (United States)

    Caughley, Alan; Sellier, Mathieu; Gschwendtner, Michael; Tucker, Alan

    2016-12-01

    A novel concept for a free-piston Stirling cryocooler has been proposed. The concept uses a pair of metal diaphragms to seal and suspend the displacer of a free-piston Stirling cryocooler. The diaphragms allow the displacer to move without rubbing or moving seals, potentially resulting in a long-life mechanism. When coupled to a metal diaphragm pressure wave generator, the system produces a complete Stirling cryocooler with no rubbing parts in the working gas space. Initial modelling of this concept using the Sage modelling tool indicates the potential for a useful cryocooler. A proof-of-concept prototype was constructed and achieved cryogenic temperatures. A second prototype was designed and constructed using the experience gained from the first. The prototype produced 29 W of cooling at 77 K and reached a no-load temperature of 56 K. Sage predicted the macroscopic behaviour of the prototype well but did not provide sufficient insights to improve performance significantly. This paper presents details of the development, modelling and testing of the proof-of-concept prototype and a second, improved prototype.

  6. Correlation of USMLE Step 1 scores with performance on dermatology in-training examinations.

    Science.gov (United States)

    Fening, Katherine; Vander Horst, Anthony; Zirwas, Matthew

    2011-01-01

    Although United States Medical Licensing Examination (USMLE) Step 1 was not designed to predict resident performance, scores are used to compare residency applicants. Multiple studies have displayed a significant correlation among Step 1 scores, in-training examination (ITE) scores, and board passage, although no such studies have been performed in dermatology. The purpose of this study is to determine if this correlation exists in dermatology, and how much of the variability in ITE scores is a result of differences in Step 1 scores. This study also seeks to determine if it is appropriate to individualize expectations for resident ITE performance. This project received institutional review board exemption. From 5 dermatology residency programs (86 residents), we collected Step 1 and ITE scores for each of the 3 years of dermatology residency, and recorded passage/failure on boards. Bivariate Pearson correlation analysis was used to assess correlation between USMLE and ITE scores. Ordinary least squares regression was computed to determine how much USMLE scores contribute to ITE variability. USMLE and ITE score correlations were highly significant (P ITE in years 1, 2, and 3, respectively. Variability in ITE scores caused by differences in USMLE scores were: ITE first-year residency = 21.8%, ITE second-year residency = 29.3%, and ITE third-year residency = 27.8%. This study had a relatively small sample size, with data from only 5 programs. There is a moderate correlation between USMLE and ITE scores, with USMLE scores explaining ∼26% of the variability in ITE scores. Copyright © 2009 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

  7. Effects of cyclic mean pressure of helium gas on performance of integral crank driven stirling cryocooler

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Yong Ju; Ko, Jun Seok; Kim, Hyo Bong; Park, Seong Je [Korea Institute of Machinery and Materials, Changwon (Korea, Republic of)

    2016-09-15

    An integral crank driven Stirling cryocooler is solidly based on concepts of direct IR detector mounting on the cryocooler's cold finger, and the integral construction of the cryocooler and Dewar envelope. Performance factors of the cryocooler depend on operating conditions of the cryocooler such as a cyclic mean pressure of the working fluid, a rotational speed of driving mechanism, a thermal environment, a targeted operation temperature and etc.. At given charging condition of helium gas, the cyclic mean pressure of helium gas in the cryocooler changes with temperatures of the cold end and the environment. In this study, effects of the cyclic mean pressure of helium gas on performances of the Stirling cryocooler were investigated by numerical analyses using the Sage software. The simulation model takes into account thermodynamic losses due to an inefficiency of regenerator, a pressure drop, a shuttle heat transfer and solid conductions. Simulations are performed for the performance variation according to the cyclic mean pressure induced by the temperature of the cold end and the environment. This paper presents P-V works in the compression and expansion space, cooling capacity, contribution of losses in the expansion space.

  8. Effects of cyclic mean pressure of helium gas on performance of integral crank driven stirling cryocooler

    International Nuclear Information System (INIS)

    Hong, Yong Ju; Ko, Jun Seok; Kim, Hyo Bong; Park, Seong Je

    2016-01-01

    An integral crank driven Stirling cryocooler is solidly based on concepts of direct IR detector mounting on the cryocooler's cold finger, and the integral construction of the cryocooler and Dewar envelope. Performance factors of the cryocooler depend on operating conditions of the cryocooler such as a cyclic mean pressure of the working fluid, a rotational speed of driving mechanism, a thermal environment, a targeted operation temperature and etc.. At given charging condition of helium gas, the cyclic mean pressure of helium gas in the cryocooler changes with temperatures of the cold end and the environment. In this study, effects of the cyclic mean pressure of helium gas on performances of the Stirling cryocooler were investigated by numerical analyses using the Sage software. The simulation model takes into account thermodynamic losses due to an inefficiency of regenerator, a pressure drop, a shuttle heat transfer and solid conductions. Simulations are performed for the performance variation according to the cyclic mean pressure induced by the temperature of the cold end and the environment. This paper presents P-V works in the compression and expansion space, cooling capacity, contribution of losses in the expansion space

  9. Development of Pulse Tube Cryocoolers at SITP for Space Application

    Science.gov (United States)

    Zhang, Ankuo; Wu, Yinong; Liu, Shaoshuai; Yu, Huiqin; Yang, Baoyu

    2018-05-01

    Over the last 10 years, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, has developed very high-efficiency pulse tube cryocoolers (PTCs) for aerospace applications. These PTCs can provide cooling power from milliwatt scale to tens of watts over a range of temperatures from 30 to 170 K and can be used to cool a variety of detectors in space applications (such as quantum interference devices, radiometers and ocean color sensors) that must operate at a specific cryogenic temperature to increase the signal-to-noise ratio, sensitivity and optical resolution. This paper reviews the development of single-stage PTCs over a range of weights from 1.6 to 12 kg that offer cooling powers at the cold temperature range from 40 to 170 K. In addition, a two-stage 30 K-PTC is under development.

  10. Associations between United States Medical Licensing Examination (USMLE) and Internal Medicine In-Training Examination (IM-ITE) scores.

    Science.gov (United States)

    McDonald, Furman S; Zeger, Scott L; Kolars, Joseph C

    2008-07-01

    Little is known about the associations of previous standardized examination scores with scores on subsequent standardized examinations used to assess medical knowledge in internal medicine residencies. To examine associations of previous standardized test scores on subsequent standardized test scores. Retrospective cohort study. One hundred ninety-five internal medicine residents. Bivariate associations of United States Medical Licensing Examination (USMLE) Steps and Internal Medicine In-Training Examination (IM-ITE) scores were determined. Random effects analysis adjusting for repeated administrations of the IM-ITE and other variables known or hypothesized to affect IM-ITE score allowed for discrimination of associations of individual USMLE Step scores on IM-ITE scores. In bivariate associations, USMLE scores explained 17% to 27% of the variance in IME-ITE scores, and previous IM-ITE scores explained 66% of the variance in subsequent IM-ITE scores. Regression coefficients (95% CI) for adjusted associations of each USMLE Step with IM-ITE scores were USMLE-1 0.19 (0.12, 0.27), USMLE-2 0.23 (0.17, 0.30), and USMLE-3 0.19 (0.09, 0.29). No single USMLE Step is more strongly associated with IM-ITE scores than the others. Because previous IM-ITE scores are strongly associated with subsequent IM-ITE scores, appropriate modeling, such as random effects methods, should be used to account for previous IM-ITE administrations in studies for which IM-ITE score is an outcome.

  11. Performance Characterization of the Astrium 10k Developmental Cryocooler

    National Research Council Canada - National Science Library

    Bruninghaus, C. H; Kallman, J. P; Tomlinson, B. J., Jr; Myrick, E

    2002-01-01

    .... Under the technology development program, Astrium (formerly Matra Marconi Space) in Stevenage, United Kingdom, developed a Stirling cycle cryocooler with four Oxford flexure compressors and a two-stage expansion cold end...

  12. Development of a fluorescent cryocooler

    International Nuclear Information System (INIS)

    Edwards, B.C.; Buchwald, M.I.; Epstein, R.I.; Gosnell, T.R.; Mungan, C.E.

    1995-01-01

    Recent work at Los Alamos National Laboratory has demonstrated the physical principles for a new type of solid-state cryocooler based on anti-Stokes fluorescence. Design studies indicate that a vibration-free, low-mass ''fluorescent cryocooler'' could operate for years with efficiencies and cooling powers comparable to current commercial systems. This paper presents concepts for a fluorescent cryocooler, design considerations and expected performance

  13. Highly Effective Thermal Regenerator for Low Temperature Cryocoolers, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Future missions to investigate the structure and evolution of the universe require highly efficient, low-temperature cryocoolers for low-noise detector systems. We...

  14. Space-Qualified Traveling-Wave Tube

    Science.gov (United States)

    Wilson, Jeffrey D.; Krawczyk, Richard; Simons, Rainee N.; Williams, Wallace D.; Robbins, Neal R.; Dibb, Daniel R.; Menninger, William L.; Zhai, Xiaoling; Benton, Robert T.

    2010-01-01

    The L-3 Communications Electron Technologies, Inc. Model 999HA traveling-wave tube (TWT), was developed for use as a high-power microwave amplifier for high-rate transmission of data and video signals from deep space to Earth (see figure). The 999HA is a successor to the 999H a non-space qualified TWT described in High-Power, High-Efficiency Ka-Band Traveling-Wave Tube (LEW-17900-1), NASA Tech Briefs, Vol. 31, No. 2 (February 2007), page 32. Operating in the 31.8-to-32.3 GHz frequency band, the 999HA has been shown to generate 252 W of continuous- wave output power at 62 percent overall power efficiency a 75-percent increase in output power over the 999H. The mass of the 999HA is 35 percent less than that of the 999H. Moreover, taking account of the elimination of a Faraday cage that is necessary for operation of the 999H but is obviated by a redesign of high-voltage feed-throughs for the 999HA, the overall reduction in mass becomes 57 percent with an 82 percent reduction in volume. Through a series of rigorous tests, the 999HA has been qualified for operation aboard spacecraft with a lifetime exceeding seven years. Offspring of the 999HA will fly on the Kepler and Lunar Reconnaissance Orbiter missions.

  15. Thermoacoustic refrigerator for space applications

    Science.gov (United States)

    Garrett, Steven L.; Adeff, Jay A.; Hofler, Thomas J.

    1993-10-01

    A new spacecraft cryocooler which uses resonant high-amplitude sound waves in inert gases to pump heat is described. The phasing of the thermoacoustic cycle is provided by thermal conduction. This 'natural' phasing allows the entire refrigerator to operate with only one moving part (the loudspeaker diaphragm). A space-qualified thermoacoustic refrigerator was flown on the Space Shuttle Discovery (STS-42) in January, 1992. It was entirely autonomous, had no sliding seals, required no lubrication, used mostly low-tolerance machined parts, and contained no expensive components. Thermoacoustics is shown to be a competitive candidate for food refrigerator/freezers and commercial/residential air conditioners. The design and performance of the Space Thermo/Acoustic Refrigerator (STAR) is described.

  16. Advanced, Long-Life Cryocooler Technology for Zero-Boil-Off Cryogen Storage, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Long-life, high-capacity cryocoolers are a critical need for future space systems utilizing stored cryogens. The cooling requirements for planetary and...

  17. Advanced, Long-Life Cryocooler Technology for Zero-Boil-Off Cryogen Storage, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Long-life, high-capacity cryocoolers are a critical need for future space systems utilizing stored cryogens. The cooling requirements for planetary and...

  18. CFD analysis of a diaphragm free-piston Stirling cryocooler

    Science.gov (United States)

    Caughley, Alan; Sellier, Mathieu; Gschwendtner, Michael; Tucker, Alan

    2016-10-01

    This paper presents a Computational Fluid Dynamics (CFD) analysis of a novel free-piston Stirling cryocooler that uses a pair of metal diaphragms to seal and suspend the displacer. The diaphragms allow the displacer to move without rubbing or moving seals. When coupled to a metal diaphragm pressure wave generator, the system produces a complete Stirling cryocooler with no rubbing parts in the working gas space. Initial modelling of this concept using the Sage modelling tool indicated the potential for a useful cryocooler. A proof-of-concept prototype was constructed and achieved cryogenic temperatures. A second prototype was designed and constructed using the experience gained from the first. The prototype produced 29 W of cooling at 77 K and reached a no-load temperature of 56 K. The diaphragm's large diameter and short stroke produces a significant radial component to the oscillating flow fields inside the cryocooler which were not modelled in the one-dimensional analysis tool Sage that was used to design the prototypes. Compared with standard pistons, the diaphragm geometry increases the gas-to-wall heat transfer due to the higher velocities and smaller hydraulic diameters. A Computational Fluid Dynamics (CFD) model of the cryocooler was constructed to understand the underlying fluid-dynamics and heat transfer mechanisms with the aim of further improving performance. The CFD modelling of the heat transfer in the radial flow fields created by the diaphragms shows the possibility of utilizing the flat geometry for heat transfer, reducing the need for, and the size of, expensive heat exchangers. This paper presents details of a CFD analysis used to model the flow and gas-to-wall heat transfer inside the second prototype cryocooler, including experimental validation of the CFD to produce a robust analysis.

  19. 4th International Cryocoolers Conference

    CERN Document Server

    Patton, George; Knox, Margaret

    1987-01-01

    The Cryocoolers 4 proceedings archives the contributions of leading international experts at the 4th International Cryocooler Conference that was held in Easton, Maryland on September 25-26, 1986. About 170 people attended the conference representing 11 countries, 14 universities, 21 government laboratories and 60 industrial companies. Thirty-one papers were presented describing advancements and applications of cryocoolers in the temperature range below 80K. This year's conference was sponsored by the David Taylor Naval Ship Research and Development Center of Annapolis, Maryland, and the conference proceedings reproduced here was published by them.

  20. Operating single quantum emitters with a compact Stirling cryocooler.

    Science.gov (United States)

    Schlehahn, A; Krüger, L; Gschrey, M; Schulze, J-H; Rodt, S; Strittmatter, A; Heindel, T; Reitzenstein, S

    2015-01-01

    The development of an easy-to-operate light source emitting single photons has become a major driving force in the emerging field of quantum information technology. Here, we report on the application of a compact and user-friendly Stirling cryocooler in the field of nanophotonics. The Stirling cryocooler is used to operate a single quantum emitter constituted of a semiconductor quantum dot (QD) at a base temperature below 30 K. Proper vibration decoupling of the cryocooler and its surrounding enables free-space micro-photoluminescence spectroscopy to identify and analyze different charge-carrier states within a single quantum dot. As an exemplary application in quantum optics, we perform a Hanbury-Brown and Twiss experiment demonstrating a strong suppression of multi-photon emission events with g((2))(0) Stirling-cooled single quantum emitter under continuous wave excitation. Comparative experiments performed on the same quantum dot in a liquid helium (LHe)-flow cryostat show almost identical values of g((2))(0) for both configurations at a given temperature. The results of this proof of principle experiment demonstrate that low-vibration Stirling cryocoolers that have so far been considered exotic to the field of nanophotonics are an attractive alternative to expensive closed-cycle cryostats or LHe-flow cryostats, which could pave the way for the development of high-quality table-top non-classical light sources.

  1. Operating single quantum emitters with a compact Stirling cryocooler

    Energy Technology Data Exchange (ETDEWEB)

    Schlehahn, A.; Krüger, L.; Gschrey, M.; Schulze, J.-H.; Rodt, S.; Strittmatter, A.; Heindel, T., E-mail: tobias.heindel@tu-berlin.de; Reitzenstein, S. [Institute of Solid State Physics, Technische Universität Berlin, 10623 Berlin (Germany)

    2015-01-15

    The development of an easy-to-operate light source emitting single photons has become a major driving force in the emerging field of quantum information technology. Here, we report on the application of a compact and user-friendly Stirling cryocooler in the field of nanophotonics. The Stirling cryocooler is used to operate a single quantum emitter constituted of a semiconductor quantum dot (QD) at a base temperature below 30 K. Proper vibration decoupling of the cryocooler and its surrounding enables free-space micro-photoluminescence spectroscopy to identify and analyze different charge-carrier states within a single quantum dot. As an exemplary application in quantum optics, we perform a Hanbury-Brown and Twiss experiment demonstrating a strong suppression of multi-photon emission events with g{sup (2)}(0) < 0.04 from this Stirling-cooled single quantum emitter under continuous wave excitation. Comparative experiments performed on the same quantum dot in a liquid helium (LHe)-flow cryostat show almost identical values of g{sup (2)}(0) for both configurations at a given temperature. The results of this proof of principle experiment demonstrate that low-vibration Stirling cryocoolers that have so far been considered exotic to the field of nanophotonics are an attractive alternative to expensive closed-cycle cryostats or LHe-flow cryostats, which could pave the way for the development of high-quality table-top non-classical light sources.

  2. Fatigue stress detection of VIRTIS cryocoolers on board Rosetta

    Science.gov (United States)

    Giuppi, Stefano; Politi, Romolo; Capria, Maria Teresa; Piccioni, Giuseppe; De Sanctis, Maria Cristina; Erard, Stéphane; Tosi, Federico; Capaccioni, Fabrizio; Filacchione, Gianrico

    Rosetta is a planetary cornerstone mission of the European Space Agency (ESA). It is devoted to the study of minor bodies of our solar system and it will be the first mission ever to land on a comet (the Jupiter-family comet 67P/Churyumov-Gerasimenko). VIRTIS-M is a sophisticated imaging spectrometer that combines two data channels in one compact instrument, respectively for the visible and the infrared range (0.25-5.0 μm). VIRTIS-H is devoted to infrared spectroscopy (2.5-5.0 μm) with high spectral resolution. Since the satellite will be inside the tail of the comet during one of the most important phases of the mission, it would not be appropriate to use a passive cooling system, due to the high flux of contaminants on the radiator. Therefore the IR sensors are cooled by two Stirling cycle cryocoolers produced by RICOR. Since RICOR operated life tests only on ground, it was decided to conduct an analysis on VIRTIS onboard Rosetta telemetries with the purpose of study possible differences in the cryocooler performancies. The analysis led to the conclusion that cryocoolers, when operating on board, are subject to a fatigue stress not present in the on ground life tests. The telemetries analysis shows a cyclic variation in cryocooler rotor angular velocity when -M or -H or both channel are operating (it has been also noted an influence of -M channel operations in -H cryocooler rotor angular velocity and vice versa) with frequencies mostly linked to operational parameters values. The frequencies have been calculated for each mission observation applying the Fast Fourier Transform (FFT). In order to evaluate possible hedge effects it has been also applied the Hanning window to compare the results. For a more complete evaluation of cryocoolers fatigue stress, for each mission observation the angular acceleration and the angular jerk have been calculated.

  3. Miniature Joule-Thomson cryocooling principles and practice

    CERN Document Server

    Maytal, Ben-Zion

    2013-01-01

    This book is the first in English being entirely dedicated to Miniature Joule-Thomson Cryocooling. The category of Joule-Thomson (JT) cryocoolers takes us back to the roots of cryogenics, in 1895, with figures like Linde and Hampson. The "cold finger" of these cryocoolers is compact, lacks moving parts, and sustains a large heat flux extraction at a steady temperature. Potentially, they cool down unbeatably fast. For example, cooling to below 100 K (minus 173 Celsius) might be accomplished within only a few seconds by liquefying argon. A level of about 120 K can be reached almost instantly with krypton. Indeed, the species of coolant plays a central role dictating the size, the intensity and the level of cryocooling. It is the JT effect that drives these cryocoolers and reflects the deviation of the "real" gas from the ideal gas properties. The nine chapters of the book are arranged in five parts. • The Common Principle of Cyrocoolers shared across the broad variety of cryocooler types • Theoretical Aspec...

  4. 5th International Conference on Cryocoolers

    CERN Document Server

    1989-01-01

    The Cryocoolers 5 proceedings archives the contributions of leading international experts at the 5th International Cryocooler Conference that was held in Monterey, California on August 18-19, 1988. The authors submitted twenty six papers describing advancements and applications of cryocoolers in the temperature range below 80K. This year's conference was hosted by the U.S. Naval Postgraduate School in Monterey, California, and the conference proceedings reproduced here were published by the Wright-Patterson AFB in Ohio.

  5. 78 FR 31444 - Amendment to the International Traffic in Arms Regulations: Revision of U.S. Munitions List...

    Science.gov (United States)

    2013-05-24

    ... USML that are controlled by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) for the... at 2 KHz*RF (in GHz) from carrier; (16) ``Space-qualified'' star tracker or star sensor with angular...

  6. Raytheon Stirling/pulse Tube Cryocooler Development

    Science.gov (United States)

    Kirkconnell, C. S.; Hon, R. C.; Kesler, C. H.; Roberts, T.

    2008-03-01

    The first generation flight-design Stirling/pulse tube "hybrid" two-stage cryocooler has entered initial performance and environmental testing. The status and early results of the testing are presented. Numerous improvements have been implemented as compared to the preceding brassboard versions to improve performance, extend life, and enhance launch survivability. This has largely been accomplished by incorporating successful flight-design features from the Raytheon Stirling one-stage cryocooler product line. These design improvements are described. In parallel with these mechanical cryocooler development efforts, a third generation electronics module is being developed that will support hybrid Stirling/pulse tube and Stirling cryocoolers. Improvements relative to the second generation design relate to improved radiation hardness, reduced parts count, and improved vibration cancellation capability. Progress on the electronics is also presented.

  7. Space Qualified Non-Destructive Evaluation and Structural Health Monitoring Technology, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NextGen Aeronautics is proposing an innovative space qualified non-destructive evaluation and health monitoring technology. The technology is built on concepts...

  8. Space Qualified Non-Destructive Evaluation and Structural Health Monitoring Technology, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Encouraged by Phase I accomplishments, the proposed Phase II program will significantly mature and align the development of a Space Qualified Non-Destructive...

  9. Operating characteristics of a single-stage Stirling cryocooler capable of providing 700 W cooling power at 77 K

    Science.gov (United States)

    Xu, Ya; Sun, Daming; Qiao, Xin; Yu, Yan S. W.; Zhang, Ning; Zhang, Jie; Cai, Yachao

    2017-04-01

    High cooling capacity Stirling cryocooler generally has hundreds to thousands watts of cooling power at liquid nitrogen temperature. It is promising in boil-off gas (BOG) recondensation and high temperature superconducting (HTS) applications. A high cooling capacity Stirling cryocooler driven by a crank-rod mechanism was developed and studied systematically. The pressure and frequency characteristics of the cryocooler, the heat rejection from the ambient heat exchanger, and the cooling performance are studied under different charging pressure. Energy conversion and distribution in the cryocooler are analyzed theoretically. With an electric input power of 10.9 kW and a rotating speed of 1450 r/min of the motor, a cooling power of 700 W at 77 K and a relative Carnot efficiency of 18.2% of the cryocooler have been achieved in the present study, and the corresponding pressure ratio in the compression space reaches 2.46.

  10. Air Force Research Laboratory Spacecraft Cryocooler Endurance Evaluation Update: FY98-99

    National Research Council Canada - National Science Library

    Tomlinson, B

    1999-01-01

    The need for long term endurance evaluation data on space cryocoolers has long been an issue due to the 10-year plus design life of this technology and the absence of any accepted accelerated testing methodology...

  11. Stirling cryocooler test results and design model verification

    International Nuclear Information System (INIS)

    Shimko, M.A.; Stacy, W.D.; McCormick, J.A.

    1990-01-01

    This paper reports on progress in developing a long-life Stirling cycle cryocooler for space borne applications. It presents the results from tests on a preliminary breadboard version of the cryocooler used to demonstrate the feasibility of the technology and to validate the regenerator design code used in its development. This machine achieved a cold-end temperature of 65 K while carrying a 1/2 Watt cooling load. The basic machine is a double-acting, flexure-bearing, split Stirling design with linear electromagnetic drives for the expander and compressors. Flat metal diaphragms replace pistons for both sweeping and sealing the machine working volumes. In addition, the double-acting expander couples to a laminar-channel counterflow recuperative heat exchanger for regeneration. A PC compatible design code was developed for this design approach that calculates regenerator loss including heat transfer irreversibilities, pressure drop, and axial conduction in the regenerator walls

  12. Raytheon's next generation compact inline cryocooler architecture

    Science.gov (United States)

    Schaefer, B. R.; Bellis, L.; Ellis, M. J.; Conrad, T.

    2014-01-01

    Since the 1970s, Raytheon has developed, built, tested and integrated high performance cryocoolers. Our versatile designs for single and multi-stage cryocoolers provide reliable operation for temperatures from 10 to 200 Kelvin with power levels ranging from 50 W to nearly 600 W. These advanced cryocoolers incorporate clearance seals, flexure suspensions, hermetic housings and dynamic balancing to provide long service life and reliable operation in all relevant environments. Today, sensors face a multitude of cryocooler integration challenges such as exported disturbance, efficiency, scalability, maturity, and cost. As a result, cryocooler selection is application dependent, oftentimes requiring extensive trade studies to determine the most suitable architecture. To optimally meet the needs of next generation passive IR sensors, the Compact Inline Raytheon Stirling 1-Stage (CI-RS1), Compact Inline Raytheon Single Stage Pulse Tube (CI-RP1) and Compact Inline Raytheon Hybrid Stirling/Pulse Tube 2-Stage (CI-RSP2) cryocoolers are being developed to satisfy this suite of requirements. This lightweight, compact, efficient, low vibration cryocooler combines proven 1-stage (RS1 or RP1) and 2-stage (RSP2) cold-head architectures with an inventive set of warm-end mechanisms into a single cooler module, allowing the moving mechanisms for the compressor and the Stirling displacer to be consolidated onto a common axis and in a common working volume. The CI cryocooler is a significant departure from the current Stirling cryocoolers in which the compressor mechanisms are remote from the Stirling displacer mechanism. Placing all of the mechanisms in a single volume and on a single axis provides benefits in terms of package size (30% reduction), mass (30% reduction), thermodynamic efficiency (>20% improvement) and exported vibration performance (≤25 mN peak in all three orthogonal axes at frequencies from 1 to 500 Hz). The main benefit of axial symmetry is that proven balancing

  13. Raytheon's next generation compact inline cryocooler architecture

    International Nuclear Information System (INIS)

    Schaefer, B. R.; Bellis, L.; Ellis, M. J.; Conrad, T.

    2014-01-01

    Since the 1970s, Raytheon has developed, built, tested and integrated high performance cryocoolers. Our versatile designs for single and multi-stage cryocoolers provide reliable operation for temperatures from 10 to 200 Kelvin with power levels ranging from 50 W to nearly 600 W. These advanced cryocoolers incorporate clearance seals, flexure suspensions, hermetic housings and dynamic balancing to provide long service life and reliable operation in all relevant environments. Today, sensors face a multitude of cryocooler integration challenges such as exported disturbance, efficiency, scalability, maturity, and cost. As a result, cryocooler selection is application dependent, oftentimes requiring extensive trade studies to determine the most suitable architecture. To optimally meet the needs of next generation passive IR sensors, the Compact Inline Raytheon Stirling 1-Stage (CI-RS1), Compact Inline Raytheon Single Stage Pulse Tube (CI-RP1) and Compact Inline Raytheon Hybrid Stirling/Pulse Tube 2-Stage (CI-RSP2) cryocoolers are being developed to satisfy this suite of requirements. This lightweight, compact, efficient, low vibration cryocooler combines proven 1-stage (RS1 or RP1) and 2-stage (RSP2) cold-head architectures with an inventive set of warm-end mechanisms into a single cooler module, allowing the moving mechanisms for the compressor and the Stirling displacer to be consolidated onto a common axis and in a common working volume. The CI cryocooler is a significant departure from the current Stirling cryocoolers in which the compressor mechanisms are remote from the Stirling displacer mechanism. Placing all of the mechanisms in a single volume and on a single axis provides benefits in terms of package size (30% reduction), mass (30% reduction), thermodynamic efficiency (>20% improvement) and exported vibration performance (≤25 mN peak in all three orthogonal axes at frequencies from 1 to 500 Hz). The main benefit of axial symmetry is that proven balancing

  14. The impact of a resident-run review curriculum and USMLE scores on the Otolaryngology in-service exam.

    Science.gov (United States)

    Redmann, Andrew J; Tawfik, Kareem O; Myer, Charles M

    2018-01-01

    Describe the association of USMLE Step 1 scores and the institution of a dedicated board review curriculum with resident performance on the Otolaryngology training examination. Retrospective cross sectional study. We reviewed American Board of Otolaryngology Training Examination (OTE) scores for an otolaryngology residency program between 2005 and 2016. USMLE Step 1 scores were collected. In 2011 a resident-run OTE review curriculum was instituted with the goal of improving test preparation. Scores were compared before and after curriculum institution. Linear regression was performed to identify predictors of OTE scores. 47 residents were evaluated, 24 before and 23 after instituting the curriculum. There was a moderate correlation between USMLE step 1 scores and OTE scores for all years. For PGY-2 residents, mean OTE scores improved from 25th percentile to 41st percentile after institution of the review curriculum (p = 0.05). PGY 3-5 residents demonstrated no significant improvement. On multivariate linear regression, after controlling for USMLE step 1 scores, a dedicated board review curriculum predicted a 23-point percentile improvement in OTE scores for PGY-2 residents (p = 0.003). For other post-graduate years, the review curriculum did not predict score improvement. USMLE step 1 scores are moderately correlated with OTE performance. A dedicated OTE review curriculum may improve OTE scores for PGY-2 residents, but such a curriculum may have less benefit for intermediate- and senior-level residents. 4. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Development of a 77K Reverse-Brayton Cryocooler with Multiple Coldheads, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — RTI will design and optimize an 80 W, 77K cryocooler based on the reverse turbo Brayton cycle (RTBC) with four identical coldheads for distributed cooling. Based on...

  16. A high efficiency hybrid stirling-pulse tube cryocooler

    Directory of Open Access Journals (Sweden)

    Xiaotao Wang

    2015-03-01

    Full Text Available This article presented a hybrid cryocooler which combines the room temperature displacers and the pulse tube in one system. Compared with a traditional pulse tube cryocooler, the system uses the rod-less ambient displacer to recover the expansion work from the pulse tube cold end to improve the efficiency while still keeps the advantage of the pulse tube cryocooler with no moving parts at the cold region. In the meantime, dual-opposed configurations for both the compression pistons and displacers reduce the cooler vibration to a very low level. In the experiments, a lowest no-load temperature of 38.5 K has been obtained and the cooling power at 80K was 26.4 W with an input electric power of 290 W. This leads to an efficiency of 24.2% of Carnot, marginally higher than that of an ordinary pulse tube cryocooler. The hybrid configuration herein provides a very competitive option when a high efficiency, high-reliability and robust cryocooler is desired.

  17. Development and Evaluation of a Student-Initiated Test Preparation Program for the USMLE Step 1 Examination.

    Science.gov (United States)

    Schwartz, Lindsay F; Lineberry, Matthew; Park, Yoon Soo; Kamin, Carol S; Hyderi, Abbas A

    2018-01-01

    Studies have documented performance on the United States Medical Licensing Examination® (USMLE) Step 1 exam as an important factor that residency program directors consider when deciding which applicants to interview and rank. Therefore, success on this exam, though only one aspect of applicant evaluation, is important in determining future career prospects for medical students. Unfortunately, mean test scores at the University of Illinois College of Medicine at Chicago (UIC) have historically been below the national average. This retrospective and quasi-experimental mixed-methods study describes the development, evaluation, and effects of a student-initiated USMLE Step 1 preparatory program at UIC. The program provided second year students with First Aid for the USMLE Step 1 at the beginning of the academic year, as well as a six month subscription to the USMLE World question bank midyear. In addition, optional peer review sessions covering basic sciences and organ systems were taught by high-performing upperclassmen. The goals of the program were to raise mean USMLE Step 1 exam scores and increase the percentage of students passing the exam on their first time. The program premiered during the 2012-13 academic year. Data from this cohort as well as four others (N = 830; 2010-2014 examinees) were gathered. Performances between preintervention (2010-12 examinees) and postintervention (2013-14 examinees) cohorts of students were compared. Focus groups and interviews with staff and students were conducted, recorded, and analyzed to investigate the impact that the program had on student interactions and perceptions of the learning environment. There was a significant difference in exam performance pre- versus postintervention, with average USMLE Step 1 scores improving by 8.82 points following the implementation of the student-initiated program, t(5.61) = 828, p Step 1 (odds ratio = 3.08, SE = 1.07, p < .01). Students and staff commented on the sense of community and

  18. Nitrogen heat pipe for cryocooler thermal shunt

    International Nuclear Information System (INIS)

    Prenger F.C.; Hill, D.D.; Daney, D.E.

    1996-01-01

    A nitrogen heat pipe was designed, built and tested for the purpose of providing a thermal shunt between the two stages of a Gifford-McMahan (GM) cryocooler during cooldown. The nitrogen heat pipe has an operating temperature range between 63 and 123 K. While the heat pipe is in this temperature range during the system cooldown, it acts as a thermal shunt between the first and second stage of the cryocooler. The heat pipe increases the heat transfer to the first stage of the cryocooler, thereby reducing the cooldown time of the system. When the heat pipe temperature drops below the triple point, the nitrogen working fluid freezes, effectively stopping the heat pipe operation. A small heat leak between cryocooler stages remains because of axial conduction along the heat pipe wall. As long as the heat pipe remains below 63 K, the heat pipe remains inactive. Heat pipe performance limits were measured and the optimum fluid charge was determined

  19. A 4 K tactical cryocooler using reverse-Brayton machines

    Science.gov (United States)

    Zagarola, M.; Cragin, K.; McCormick, J.; Hill, R.

    2017-12-01

    Superconducting electronics and spectral-spatial holography have the potential to revolutionize digital communications, but must operate at cryogenic temperatures, near 4 K. Liquid helium is undesirable for military missions due to logistics and scarcity, and commercial low temperature cryocoolers are unable to meet size, weight, power, and environmental requirements for many missions. To address this need, Creare is developing a reverse turbo-Brayton cryocooler that provides refrigeration at 4.2 K and rejects heat at 77 K to an upper-stage cryocooler or through boil-off of liquid nitrogen. The cooling system is predicted to reduce size, weight, and input power by at least an order of magnitude as compared to the current state-of-the-art 4.2 K cryocooler. For systems utilizing nitrogen boil-off, the boil-off rate is reasonable. This paper reviews the design of the cryocooler, the key components, and component test results.

  20. USMLE performances in a predominantly Asian and Pacific Islander population of medical students in a problem-based learning curriculum.

    Science.gov (United States)

    Kasuya, Richard T; Naguwa, Gwen S; Guerrero, Anthony P S; Hishinuma, Earl S; Lindberg, Marlene A; Judd, Nanette K

    2003-05-01

    To compare the USMLE performances of students of various ethnicities, predominantly Pacific Islander and Asian, at one medical school and to examine the predictive validity of MCAT scores for USMLE performance. A total of 258 students in the graduating classes of 1996-2000 at the University of Hawai'i School of Medicine were classified by ethnicity. Demographic and performance characteristics of the groups were examined, and MCAT scores with and without undergraduate science GPA were used to predict USMLE performance. Under- and over-prediction rates were computed for each ethnic group. Ethnic groups did not differ significantly by gender or undergraduate GPA. Chinese, Caucasian, and Other Asian students tended to have higher MCAT scores than Hawaiian/other Pacific Islander, and Filipino students. Ethnic groups did not differ significantly in prediction of USMLE Step 1 performance. For Step 2, MCAT scores significantly over-predicted performance of Filipino students and tended to under-predict performance of Caucasian students. Although MCAT scores and science GPA were good predictors of USMLE performance, ethnic differences were found in the degrees of their predictive validity. These findings both replicate and extend results of earlier studies, and again point to the importance of exploring additional predictor variables. The authors encourage future research on the effects of the following factors on success in medical school: reading and test-taking skills, socio-cultural and environmental influences on learning, communication styles, primary language use, family support, and family responsibilities.

  1. Raytheon's next generation compact inline cryocooler architecture

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, B. R.; Bellis, L.; Ellis, M. J.; Conrad, T. [Raytheon Space and Airborne Systems, 2000 E. El Segundo Blvd., El Segundo, CA 90245 (United States)

    2014-01-29

    Since the 1970s, Raytheon has developed, built, tested and integrated high performance cryocoolers. Our versatile designs for single and multi-stage cryocoolers provide reliable operation for temperatures from 10 to 200 Kelvin with power levels ranging from 50 W to nearly 600 W. These advanced cryocoolers incorporate clearance seals, flexure suspensions, hermetic housings and dynamic balancing to provide long service life and reliable operation in all relevant environments. Today, sensors face a multitude of cryocooler integration challenges such as exported disturbance, efficiency, scalability, maturity, and cost. As a result, cryocooler selection is application dependent, oftentimes requiring extensive trade studies to determine the most suitable architecture. To optimally meet the needs of next generation passive IR sensors, the Compact Inline Raytheon Stirling 1-Stage (CI-RS1), Compact Inline Raytheon Single Stage Pulse Tube (CI-RP1) and Compact Inline Raytheon Hybrid Stirling/Pulse Tube 2-Stage (CI-RSP2) cryocoolers are being developed to satisfy this suite of requirements. This lightweight, compact, efficient, low vibration cryocooler combines proven 1-stage (RS1 or RP1) and 2-stage (RSP2) cold-head architectures with an inventive set of warm-end mechanisms into a single cooler module, allowing the moving mechanisms for the compressor and the Stirling displacer to be consolidated onto a common axis and in a common working volume. The CI cryocooler is a significant departure from the current Stirling cryocoolers in which the compressor mechanisms are remote from the Stirling displacer mechanism. Placing all of the mechanisms in a single volume and on a single axis provides benefits in terms of package size (30% reduction), mass (30% reduction), thermodynamic efficiency (>20% improvement) and exported vibration performance (≤25 mN peak in all three orthogonal axes at frequencies from 1 to 500 Hz). The main benefit of axial symmetry is that proven balancing

  2. Study of low vibration 4 K pulse tube cryocoolers

    Science.gov (United States)

    Xu, Mingyao; Nakano, Kyosuke; Saito, Motokazu; Takayama, Hirokazu; Tsuchiya, Akihiro; Maruyama, Hiroki

    2012-06-01

    Sumitomo Heavy Industries, Ltd. (SHI) has been continuously improving the efficiency and reducing the vibration of a 4 K pulse tube cryocooler. One advantage of a pulse tube cryocooler over a GM cryocooler is low vibration. In order to reduce vibration, both the displacement and the acceleration have to be reduced. The vibration acceleration can be reduced by splitting the valve unit from the cold head. One simple way to reduce vibration displacement is to increase the wall thickness of the tubes on the cylinder. However, heat conduction loss increases while the wall thickness increases. To overcome this dilemma, a novel concept, a tube with non-uniform wall thickness, is proposed. Theoretical analysis of this concept, and the measured vibration results of an SHI lowvibration pulse tube cryocooler, will be introduced in this paper.

  3. An efficient cooling loop for connecting cryocooler to a helium reservoir

    International Nuclear Information System (INIS)

    Taylor, C.E.; Abbott, C.S.R.; Leitner, D.; Leitner, M.; Lyneis, C.M.

    2003-01-01

    The magnet system of the VENUS ECR Ion Source at LBNL has two 1.5-watt cryocoolers suspended in the cryostat vacuum. Helium vapor from the liquid reservoir is admitted to a finned condenser bolted to the cryocooler 2nd stage and returns as liquid via gravity. Small-diameter flexible tubes allow the cryocoolers to be located remotely from the reservoir. With 3.1 watts load, the helium reservoir is maintained at 4.35 K, 0.05K above the cryocooler temperature. Design, analysis, and performance are presented

  4. MODIL cryocooler producibility demonstration project results

    International Nuclear Information System (INIS)

    Cruz, G.E.; Franks, R.M.

    1993-01-01

    The production of large quantities of spacecraft needed by SDIO will require a cultural change in design and production practices. Low rates production and the need for exceedingly high reliability has driven the industry to custom designed, hand crafted, and exhaustively tested satellites. These factors have mitigated against employing design and manufacturing cost reduction methods commonly used in tactical missile production. Additional challenges to achieving production efficiencies are presented by the SDI spacecraft mission requirement. IR sensor systems, for example, are comprised of subassemblies and components that require the design, manufacture, and maintenance of ultra precision tolerances over challenging operational lifetimes. These IR sensors demand the use of reliable, closed loop, cryogenic refrigerators or active cryocoolers to meet stringent system acquisition and pointing requirements. The authors summarize some spacecraft cryocooler requirements and discuss observations regarding Industry's current production capabilities of cryocoolers. The results of the Lawrence Livermore National Laboratory (LLNL) Spacecraft Fabrication and Test (SF and T) MODIL's Phase I producibility demonstration project is presented

  5. A survey of collection development for United States Medical Licensing Examination (USMLE) and National Board Dental Examination (NBDE) preparation material.

    Science.gov (United States)

    Hendrix, Dean; Hasman, Linda

    2008-07-01

    The research sought to ascertain medical and dental libraries' collection development policies, evaluation methods, purchase decisions, and issues that relate to print and electronic United States Medical Licensing Examination (USMLE) and National Board Dental Examination (NBDE) preparation materials. The investigators surveyed librarians supporting American Association of Medical Colleges (AAMC)-accredited medical schools (n = 58/125) on the USMLE and librarians supporting American Dental Association (ADA)-accredited dental schools (n = 23/56) on the NBDE. The investigators analyzed the data by cross-tabulating and filtering the results using EFM Continuum web survey software. Investigators also surveyed print and electronic USMLE and NBDE preparation materials from 2004-2007 to determine the number of publications and existence of reviews. A majority of responding AAMC libraries (62%, n = 58) provide at least 1 electronic or online USMLE preparation resource and buy an average of 11.6 print USMLE titles annually. Due to a paucity of NBDE print and electronic resources, ADA libraries bought significantly fewer print resources, and only 1 subscribed to an electronic resource. The most often reported evaluation methods for both populations were feedback from medical or dental students, feedback from medical or dental faculty, and online trials. Some AAMC (10%, n = 58) and ADA libraries (39%, n = 23) libraries reported that no evaluation of these materials occured at their libraries. From 2004-2007, publishers produced 45 USMLE preparation resources (total n = 546) to every 1 NBDE preparation resource (total n = 12). Users' needs, institutional missions and goals, financial status, and official collection policies most often underlie decisions to collect or not collect examination preparation materials. Evaluating the quality of examination preparation materials can be problematic due to lack of published reviews, lack of usability testing by libraries, and

  6. Ultra-low-vibration pulse-tube cryocooler system - cooling capacity and vibration

    Science.gov (United States)

    Ikushima, Yuki; Li, Rui; Tomaru, Takayuki; Sato, Nobuaki; Suzuki, Toshikazu; Haruyama, Tomiyoshi; Shintomi, Takakazu; Yamamoto, Akira

    2008-09-01

    This report describes the development of low-vibration cooling systems with pulse-tube (PT) cryocoolers. Generally, PT cryocoolers have the advantage of lower vibrations in comparison to those of GM cryocoolers. However, cooling systems for the cryogenic laser interferometer observatory (CLIO), which is a gravitational wave detector, require an operational vibration that is sufficiently lower than that of a commercial PT cryocooler. The required specification for the vibration amplitude in cold stages is less than ±1 μm. Therefore, during the development of low-vibration cooling systems for the CLIO, we introduced advanced countermeasures for commercial PT cryocoolers. The cooling performance and the vibration amplitude were evaluated. The results revealed that 4 K and 80 K PT cooling systems with a vibration amplitude of less than ±1 μm and cooling performance of 4.5 K and 70 K at heat loads of 0.5 W and 50 W, respectively, were developed successfully.

  7. Magnet/cryocooler integration for thermal stability in conduction-cooled systems

    Science.gov (United States)

    Chang, H.-M.; Kwon, K. B.

    2002-05-01

    The stability conditions that take into accounts the size of superconducting magnets and the refrigeration capacity of cryocoolers are investigated for the conduction-cooled systems without liquid cryogens. The worst scenario in the superconducting systems is that the heat generation in the resistive state exceeds the refrigeration, causing a rise in the temperature of the magnet winding and leading to burnout. It is shown by an analytical solution that in the continuously resistive state, the temperature may increase indefinitely or a stable steady state may be reached, depending upon the relative size of the magnet with respect to the refrigeration capacity of the cryocooler. The stability criteria include the temperature-dependent properties of the magnet materials and the refrigeration characteristics of the cryocooler. A useful graphical scheme is presented and the design of the stable magnet/cryocooler interface is demonstrated.

  8. Emotional Intelligence in Medical Students is Inversely Correlated with USMLE Step 1 Score: Is there a Better Way to Screen Applicants?

    Directory of Open Access Journals (Sweden)

    Allison Lee Boden

    2018-03-01

    Full Text Available Background: The primary aim of this study was to investigate whether USMLE board scores correlate with the emotional intelligence of medical students. We hypothesized that higher Step 1 scores would be associated with lower emotional intelligence.Methods: This prospective study included medical students who self-reported their USMLE Step 1 score and completed a survey designed to measure their emotional intelligence. The survey was composed of a Grit Scale, a Hardiness-Resilience quiz, and the “Reading the Mind in the Eyes” quiz. For participants who completed all three instruments, a composite score was equal to the sum of the three scoresThis study was performed at Emory University School of Medicine in Atlanta, Georgia. Of the 85 medical students who were recruited to participate, 72 completed all aspects of this study (85% completion rate.Results: Pearson correlation analyses showed that grit (r=-0.105, P=0.34, hardiness-resilience (r=-0.230, P=0.04, the eye quiz (r=-0.033, P=0.79, and the composite score (r=-0.187, P=0.12 wereinversely correlated with USMLE scores. Participants who scored higher than the national average had a lower mean hardiness score compared to those who scored lower than the national average (P=0.03. Those who scored at least one standard deviation above the national average had a lowermean hardiness score (P=0.05 and a lower composite score (P=0.04.Conclusion: Higher USMLE Step 1 scores are associated with lower emotional intelligence, namely hardiness, in medical students.Keywords: EMOTIONAL INTELLIGENCE, USMLE STEP 1, HARDINESS, GRIT, RESIDENCY SELECTION

  9. Dynamic simulation of 10 kW Brayton cryocooler for HTS cable

    Science.gov (United States)

    Chang, Ho-Myung; Park, Chan Woo; Yang, Hyung Suk; Hwang, Si Dole

    2014-01-01

    Dynamic simulation of a Brayton cryocooler is presented as a partial effort of a Korean governmental project to develop 1˜3 km HTS cable systems at transmission level in Jeju Island. Thermodynamic design of a 10 kW Brayton cryocooler was completed, and a prototype construction is underway with a basis of steady-state operation. This study is the next step to investigate the transient behavior of cryocooler for two purposes. The first is to simulate and design the cool-down process after scheduled or unscheduled stoppage. The second is to predict the transient behavior following the variation of external conditions such as cryogenic load or outdoor temperature. The detailed specifications of key components, including plate-fin heat exchangers and cryogenic turbo-expanders are incorporated into a commercial software (Aspen HYSYS) to estimate the temporal change of temperature and flow rate over the cryocooler. An initial cool-down scenario and some examples on daily variation of cryocooler are presented and discussed, aiming at stable control schemes of a long cable system.

  10. Dynamic simulation of 10 kW Brayton cryocooler for HTS cable

    International Nuclear Information System (INIS)

    Chang, Ho-Myung; Park, Chan Woo; Yang, Hyung Suk; Hwang, Si Dole

    2014-01-01

    Dynamic simulation of a Brayton cryocooler is presented as a partial effort of a Korean governmental project to develop 1∼3 km HTS cable systems at transmission level in Jeju Island. Thermodynamic design of a 10 kW Brayton cryocooler was completed, and a prototype construction is underway with a basis of steady-state operation. This study is the next step to investigate the transient behavior of cryocooler for two purposes. The first is to simulate and design the cool-down process after scheduled or unscheduled stoppage. The second is to predict the transient behavior following the variation of external conditions such as cryogenic load or outdoor temperature. The detailed specifications of key components, including plate-fin heat exchangers and cryogenic turbo-expanders are incorporated into a commercial software (Aspen HYSYS) to estimate the temporal change of temperature and flow rate over the cryocooler. An initial cool-down scenario and some examples on daily variation of cryocooler are presented and discussed, aiming at stable control schemes of a long cable system

  11. Dynamic simulation of 10 kW Brayton cryocooler for HTS cable

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Ho-Myung; Park, Chan Woo [Hong Ik University, Department of Mechanical Engineering, Seoul, 121-791 (Korea, Republic of); Yang, Hyung Suk; Hwang, Si Dole [KEPCO Research Institute, Daejeon, 305-760 (Korea, Republic of)

    2014-01-29

    Dynamic simulation of a Brayton cryocooler is presented as a partial effort of a Korean governmental project to develop 1∼3 km HTS cable systems at transmission level in Jeju Island. Thermodynamic design of a 10 kW Brayton cryocooler was completed, and a prototype construction is underway with a basis of steady-state operation. This study is the next step to investigate the transient behavior of cryocooler for two purposes. The first is to simulate and design the cool-down process after scheduled or unscheduled stoppage. The second is to predict the transient behavior following the variation of external conditions such as cryogenic load or outdoor temperature. The detailed specifications of key components, including plate-fin heat exchangers and cryogenic turbo-expanders are incorporated into a commercial software (Aspen HYSYS) to estimate the temporal change of temperature and flow rate over the cryocooler. An initial cool-down scenario and some examples on daily variation of cryocooler are presented and discussed, aiming at stable control schemes of a long cable system.

  12. Advances in single- and multi-stage Stirling-type pulse tube cryocoolers for space applications in NLIP/SITP/CAS

    Science.gov (United States)

    Dang, Haizheng; Tan, Jun; Zha, Rui; Li, Jiaqi; Zhang, Lei; Zhao, Yibo; Gao, Zhiqian; Bao, Dingli; Li, Ning; Zhang, Tao; Zhao, Yongjiang; Zhao, Bangjian

    2017-12-01

    This paper presents a review of recent advances in single- and multi-stage Stirling-type pulse tube cryocoolers (SPTCs) for space applications developed at the National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences (NLIP/SITP/CAS). A variety of single-stage SPTCs operating at 25-150 K have been developed, including several mid-sized ones operating at 80-110 K. Significant progress has been achieved in coolers operating at 30-40 K which use common stainless steel meshes as regenerator matrices. Another important advance is the micro SPTCs with an overall mass of 300-800 g operating at high frequencies varying from 100 Hz to 400 Hz. The main purpose of developing two-stage SPTCs is to simultaneously acquire cooling capacities at both stages, obviating the need for auxiliary precooling in various applications. The three-stage SPTCs are developed mainly for applications at around 10 K, which are also used for precooling the J-T coolers to achieve further lower temperatures. The four-stage SPTCs are developed to directly achieve the liquid helium temperature for cooling space low-Tc superconducting devices and for the deep space exploration as well. Several typical development programs are described and an overview of the cooler performances is presented.

  13. Cryocooler applications for high-temperature superconductor magnetic bearings

    International Nuclear Information System (INIS)

    Niemann, R. C.

    1998-01-01

    The efficiency and stability of rotational magnetic suspension systems are enhanced by the use of high-temperature superconductor (HTS) magnetic bearings. Fundamental aspects of the HTS magnetic bearings and rotational magnetic suspension are presented. HTS cooling can be by liquid cryogen bath immersion or by direct conduction, and thus there are various applications and integration issues for cryocoolers. Among the numerous cryocooler aspects to be considered are installation; operating temperature; losses; and vacuum pumping

  14. From space qualified fiber optic gyroscope to generic fiber optic solutions available for space application

    Science.gov (United States)

    Buret, Thomas; Ramecourt, David; Napolitano, Fabien

    2017-11-01

    The aim of this article is to present how the qualification of the Fiber Optic Gyroscope technology from IXSEA has been achieved through the qualification of a large range of optical devices and related manufacturing processes. These qualified optical devices and processes, that are now fully mastered by IXSEA through vertical integration of the technology, can be used for other space optical sensors. The example of the SWARM project will be discussed.

  15. Development of 1 kW Stirling cryocooler using a linear compressor

    International Nuclear Information System (INIS)

    Ko, J; Kim, H; Hong, Y J; Yeom, H; In, S; Park, S J

    2015-01-01

    Cryogenic cooling systems for HTS electric power devices require a reliable and efficient high-capacity cryocooler. A Striling cryocooler with a linear compressor can be a good candidate. It has advantages of low vibration and long maintenance cycle compared with a kinematic-driven Stirling cryocooler. In this study, we developed a dual-opposed linear compressor of 12 kW electric input power with two 6 kW linear motors. Electrical performance of the fabricated linear compressor is verified by experimental measurement of thrust constant. The developed Stirling cryocooler has a gamma-type configuration. The piston and displacer are supported with a flexure spring. A slit-type heat exchanger is adopted for the cold and warm-end, and the generated heat is rejected by cooling water. In the cooling performance test, waveforms of voltage, current, displacement and pressure are obtained and their amplitude and phase difference are analysed. The developed cryocooler reaches 47.8 K within 23.4 min. with no-load. Heat load tests shows a cooling capacity of 440 W at 78.1 K with 6.45 kW of electric input power and 19.4 of % Carnot COP. (paper)

  16. Development of High Capacity Split Stirling Cryocooler for HTS

    Science.gov (United States)

    Yumoto, Kenta; Nakano, Kyosuke; Hiratsuka, Yoshikatsu

    Sumitomo Heavy Industries, Ltd. (SHI) developed a high-power Stirling-type pulse tube cryocooler for cooling high-temperature superconductor (HTS) devices, such as superconductor motors, superconducting magnetic energy storage (SMES), and fault current limiters. The experimental results of a prototype pulse tube cryocooler were reported in September 2013. For a U-type expander, the cooling capacity was 151 W at 70 K with a compressor input power of 4 kW. Correspondingly, the coefficient of performance (COP) was about 0.038. However, the efficiency of the cryocooler is required to be COP > 0.1 and it was found that, theoretically, it is difficult to further improve the efficiency of a pulse tube cryocooler because the workflow generated at the hot end of the pulse tube cannot be recovered. Therefore, it was decided to change the expander to a free-piston type from a pulse tube type. A prototype was developed and preliminary experiments were conducted. A cooling capacity of 120 W at 70 K with a compressor input power of 2.15 kW with corresponding COP of 0.056, was obtained. The detailed results are reported in this paper.

  17. Influence of minor geometric features on Stirling pulse tube cryocooler performance

    Science.gov (United States)

    Fang, T.; Spoor, P. S.; Ghiaasiaan, S. M.; Perrella, M.

    2017-12-01

    Minor geometric features and imperfections are commonly introduced into the basic design of multi-component systems to simplify or reduce the manufacturing expense. In this work, the cooling performance of a Stirling type cryocooler was tested in different driving powers, cold-end temperatures and inclination angles. A series of Computational Fluid Dynamics (CFD) simulations based on a prototypical cold tip was carried out. Detailed CFD model predictions were compared with the experiment and were used to investigate the impact of such apparently minor geometric imperfections on the performance of Stirling type pulse tube cryocoolers. Predictions of cooling performance and gravity orientation sensitivity were compared with experimental results obtained with the cryocooler prototypes. The results indicate that minor geometry features in the cold tip assembly can have considerable negative effects on the gravity orientation sensitivity of a pulse tube cryocooler.

  18. Development of miniature moving magnet cryocooler SX040

    Science.gov (United States)

    Rühlich, I.; Mai, M.; Rosenhagen, C.; Schreiter, A.; Möhl, C.

    2011-06-01

    State of the art high performance cooled IR systems need to have more than just excellent E/O performance. Minimum size weight and power (SWaP) are the design goals to meet our forces' mission requirements. Key enabler for minimum SWaP of IR imagers is the operation temperature of the focal plane array (FPA) employed. State of the art MCT or InAsSb nBn technology has the potential to rise the FPA temperature from 77 K to 130-150 K (high operation temperature HOT) depending on the specific cut-off wavelength. Using a HOT FPA will significantly lower SWaP and keep those parameters finally dominated by the employed cryocooler. Therefore compact high performance cryocoolers are mandatory. For highest MTTF life AIM developed its Flexure Bearing Moving Magnet product family "SF". Such coolers achieve more than 20000 h MTTF with Stirling type expander and more than 5 years MTTF life with Pulse Tube coldfinger (like for Space applications). To keep the high lifetime potential but to significantly improve SWaP AIM is developing its "SX" type cooler family. The new SX040 cooler incorporates a highly efficient dual piston Moving Magnet driving mechanism resulting in very compact compressor of less than 100mm length. The cooler's high lifetime is also achieved by placing the coils outside the helium vessel as usual for moving magnet motors. The mating ¼" expander is extremely compact with less than 63 mm length. This allows a total dewar length from optical window to expander warm end of less than 100 mm even for large cold shields. The cooler is optimized for HOT detectors with operating temperatures exceeding 95 K. While this kind of cooler is the perfect match for many applications, handheld sights or targeting devices for the dismounted soldier are even more challenging with respect to SWaP. AIM therefore started to develop an even smaller cooler type with single piston and balancer. This paper gives an overview on the development of this new compact cryocooler. Technical

  19. Suppression of Transient Events by Levitation (STABLE): Results From the USML-2 Mission. Experiment 38

    Science.gov (United States)

    Nurre, Gerald S.; Edberg, Donald L.

    1998-01-01

    Microgravity science payloads can be extremely sensitive to vibrations from machinery, acoustics, ventilation, and crew activity. Suppression of Transient Acceleration by Levitation (STABLE) is an active vibration isolation system designed to protect payloads from these disturbances. This paper gives an account of results from the flight demonstration of the STABLE microgravity isolation system, which was developed and successfully flight tested in orbit during USML-2, with the participation of Astronaut Fred Leslie. Following a very brief description of the operational principles, the hardware and software design, and performance criteria, results of the analysis of measured flight data are presented to provide an evaluation of system performance parameters, including acceleration attenuation, assessment of sway space, system power consumption, and other factors critical to the performance of an isolation system. Lessons learned and potential design improvements and evolutions are discussed. Data reduction by Robert Boucher of McDonnell Douglas Aerospace (MDA) was substantially assisted by Kenneth Hrovat of Tal-Cut, Inc., under support from National Aeronautics and Space Administration/Lewis Research Center (LeRC), Cleveland, OH.

  20. Design of a Two-stage High-capacity Stirling Cryocooler Operating below 30K

    Science.gov (United States)

    Wang, Xiaotao; Dai, Wei; Zhu, Jian; Chen, Shuai; Li, Haibing; Luo, Ercang

    The high capacity cryocooler working below 30K can find many applications such as superconducting motors, superconducting cables and cryopump. Compared to the GM cryocooler, the Stirling cryocooler can achieve higher efficiency and more compact structure. Because of these obvious advantages, we have designed a two stage free piston Stirling cryocooler system, which is driven by a moving magnet linear compressor with an operating frequency of 40 Hz and a maximum 5 kW input electric power. The first stage of the cryocooler is designed to operate in the liquid nitrogen temperature and output a cooling power of 100 W. And the second stage is expected to simultaneously provide a cooling power of 50 W below the temperature of 30 K. In order to achieve the best system efficiency, a numerical model based on the thermoacoustic model was developed to optimize the system operating and structure parameters.

  1. Performance analysis on free-piston Stirling cryocooler based on an idealized mathematical model

    Science.gov (United States)

    Guo, Y. X.; Chao, Y. J.; Gan, Z. H.; Li, S. Z.; Wang, B.

    2017-12-01

    Free-piston Stirling cryocoolers have extensive applications for its simplicity in structure and decrease in mass. However, the elimination of the motor and the crankshaft has made its thermodynamic characteristic different from that of Stirling cryocoolers with displacer driving mechanism. Therefore, an idealized mathematical model has been established, and with this model, an attempt has been made to analyse the thermodynamic characteristic and the performance of free-piston Stirling cryocooler. To certify this mathematical model, a comparison has been made between the model and a numerical model. This study reveals that due to the displacer damping force necessary for the production of cooling capacity, the free-piston Stirling cryocooler is inherently less efficient than Stirling cryocooler with displacer driving mechanism. Viscous flow resistance and incomplete heat transfer in the regenerator are the two major causes of the discrepancy between the results of the idealized mathematical model and the numerical model.

  2. The effect of low temperature cryocoolers on the development of low temperature superconducting magnets

    International Nuclear Information System (INIS)

    Green, Michael A.

    2000-01-01

    The commercial development of reliable 4 K cryocoolers improves the future prospects for magnets made from low temperature superconductors (LTS). The hope of the developers of high temperature superconductors (HTS) has been to replace liquid helium cooled LTS magnets with HTS magnets that operate at or near liquid nitrogen temperature. There has been limited success in this endeavor, but continued problems with HTS conductors have greatly slowed progress toward this goal. The development of cryocoolers that reliably operate below 4 K will allow magnets made from LTS conductor to remain very competitive for many years to come. A key enabling technology for the use of low temperature cryocoolers on LTS magnets has been the development of HTS leads. This report describes the characteristics of LTS magnets that can be successfully melded to low-temperature cryocoolers. This report will also show when it is not appropriate to consider the use of low-temperature cryocoolers to cool magnets made with LTS conductor. A couple of specific examples of LTS magnets where cryocoolers can be used are given

  3. Exploring the Relationships Between USMLE Performance and Disciplinary Action in Practice: A Validity Study of Score Inferences From a Licensure Examination.

    Science.gov (United States)

    Cuddy, Monica M; Young, Aaron; Gelman, Andrew; Swanson, David B; Johnson, David A; Dillon, Gerard F; Clauser, Brian E

    2017-12-01

    Physicians must pass the United States Medical Licensing Examination (USMLE) to obtain an unrestricted license to practice allopathic medicine in the United States. Little is known, however, about how well USMLE performance relates to physician behavior in practice, particularly conduct inconsistent with safe, effective patient care. The authors examined the extent to which USMLE scores relate to the odds of receiving a disciplinary action from a U.S. state medical board. Controlling for multiple factors, the authors used non-nested multilevel logistic regression analyses to estimate the relationships between scores and receiving an action. The sample included 164,725 physicians who graduated from U.S. MD-granting medical schools between 1994 and 2006. Physicians had a mean Step 1 score of 214 (standard deviation [SD] = 21) and a mean Step 2 Clinical Knowledge (CK) score of 213 (SD = 23). Of the physicians, 2,205 (1.3%) received at least one action. Physicians with higher Step 2 CK scores had lower odds of receiving an action. A 1-SD increase in Step 2 CK scores corresponded to a decrease in the chance of disciplinary action by roughly 25% (odds ratio = 0.75; 95% CI = 0.70-0.80). After accounting for Step 2 CK scores, Step 1 scores were unrelated to the odds of receiving an action. USMLE Step 2 CK scores provide useful information about the odds a physician will receive an official sanction for problematic practice behavior. These results provide validity evidence supporting current interpretation and use of Step 2 CK scores.

  4. A nonproprietary, nonsecret program for calculating Stirling cryocoolers

    Science.gov (United States)

    Martini, W. R.

    1985-01-01

    A design program for an integrated Stirling cycle cryocooler was written on an IBM-PC computer. The program is easy to use and shows the trends and itemizes the losses. The calculated results were compared with some measured performance values. The program predicts somewhat optimistic performance and needs to be calibrated more with experimental measurements. Adding a multiplier to the friction factor can bring the calculated rsults in line with the limited test results so far available. The program is offered as a good framework on which to build a truly useful design program for all types of cryocoolers.

  5. High-resolution X-ray crystal structure of bovine H-protein using the high-pressure cryocooling method

    International Nuclear Information System (INIS)

    Higashiura, Akifumi; Ohta, Kazunori; Masaki, Mika; Sato, Masaru; Inaka, Koji; Tanaka, Hiroaki; Nakagawa, Atsushi

    2013-01-01

    Using the high-pressure cryocooling method, the high-resolution X-ray crystal structure of bovine H-protein was determined at 0.86 Å resolution. This is the first ultra-high-resolution structure obtained from a high-pressure cryocooled crystal. Recently, many technical improvements in macromolecular X-ray crystallography have increased the number of structures deposited in the Protein Data Bank and improved the resolution limit of protein structures. Almost all high-resolution structures have been determined using a synchrotron radiation source in conjunction with cryocooling techniques, which are required in order to minimize radiation damage. However, optimization of cryoprotectant conditions is a time-consuming and difficult step. To overcome this problem, the high-pressure cryocooling method was developed (Kim et al., 2005 ▶) and successfully applied to many protein-structure analyses. In this report, using the high-pressure cryocooling method, the X-ray crystal structure of bovine H-protein was determined at 0.86 Å resolution. Structural comparisons between high- and ambient-pressure cryocooled crystals at ultra-high resolution illustrate the versatility of this technique. This is the first ultra-high-resolution X-ray structure obtained using the high-pressure cryocooling method

  6. Factors Associated With Surgery Clerkship Performance and Subsequent USMLE Step Scores.

    Science.gov (United States)

    Dong, Ting; Copeland, Annesley; Gangidine, Matthew; Schreiber-Gregory, Deanna; Ritter, E Matthew; Durning, Steven J

    2018-03-12

    We conducted an in-depth empirical investigation to achieve a better understanding of the surgery clerkship from multiple perspectives, including the influence of clerkship sequence on performance, the relationship between self-logged work hours and performance, as well as the association between surgery clerkship performance with subsequent USMLE Step exams' scores. The study cohort consisted of medical students graduating between 2015 and 2018 (n = 687). The primary measures of interest were clerkship sequence (internal medicine clerkship before or after surgery clerkship), self-logged work hours during surgery clerkship, surgery NBME subject exam score, surgery clerkship overall grade, and Step 1, Step 2 CK, and Step 3 exam scores. We reported the descriptive statistics and conducted correlation analysis, stepwise linear regression analysis, and variable selection analysis of logistic regression to answer the research questions. Students who completed internal medicine clerkship prior to surgery clerkship had better performance on surgery subject exam. The subject exam score explained an additional 28% of the variance of the Step 2 CK score, and the clerkship overall score accounted for an additional 24% of the variance after the MCAT scores and undergraduate GPA were controlled. Our finding suggests that the clerkship sequence does matter when it comes to performance on the surgery NBME subject exam. Performance on the surgery subject exam is predictive of subsequent performance on future USMLE Step exams. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  7. AIM cryocooler developments for HOT detectors

    Science.gov (United States)

    Rühlich, I.; Mai, M.; Withopf, A.; Rosenhagen, C.

    2014-06-01

    Significantly increased FPA temperatures for both Mid Wave and Long Wave IR detectors, i.e. HOT detectors, which have been developed in recent years are now leaving the development phase and are entering real application. HOT detectors allowing to push size weight and power (SWaP) of Integrated Detectors Cooler Assemblies (IDCA's) to a new level. Key component mainly driving achievable weight, volume and power consumption is the cryocooler. AIM cryocooler developments are focused on compact, lightweight linear cryocoolers driven by compact and high efficient digital cooler drive electronics (DCE) to also achieve highest MTTF targets. This technology is using moving magnet driving mechanisms and dual or single piston compressors. Whereas SX030 which was presented at SPIE in 2012 consuming less 3 WDC to operate a typical IDCA at 140K, next smaller cooler SX020 is designed to provide sufficient cooling power at detector temperature above 160K. The cooler weight of less than 200g and a total compressor length of 60mm makes it an ideal solution for all applications with limited weight and power budget, like in handheld applications. For operating a typical 640x512, 15μm MW IR detector the power consumption will be less than 1.5WDC. MTTF for the cooler will be in excess of 30,000h and thus achieving low maintenance cost also in 24/7 applications. The SX020 compressor is based on a single piston design with integrated passive balancer in a new design achieves very low exported vibration in the order of 100mN in the compressor axis. AIM is using a modular approach, allowing the chose between 5 different compressor types for one common Stirling expander. The 6mm expander with a total length of 74mm is now available in a new design that fits into standard dewar bores originally designed for rotary coolers. Also available is a 9mm coldfinger in both versions. In development is an ultra-short expander with around 35mm total length to achieve highest compactness. Technical

  8. Recent development status of stirling type pulse tube cryocooler for HTS

    International Nuclear Information System (INIS)

    Hiratsuka, Y; Nakano, K; Kato, T

    2014-01-01

    Sumitomo Heavy Industries, Ltd. (SHI) has been developing a high power stirling type pulse tube cryocooler. For the purpose of cooling high-temperature superconductor (HTS) devices, such as superconductor motor, SMES and current fault limiter, requested specifications from the devices to a cryocooler are compact size, light weight, high efficiency and high reliability. Especially, the cryocooler must be demanded COP > 0.1 in the efficiency. The experimental results of prototype pulse tube cryocooler were reported in June 2012 [1]. For an In-line type expander, the cooling capacity was 210 W at 77 K and the minimum temperature was 37 K when the compressor input power was 3.8 kW and the operating frequency was 49 Hz. Accordingly, COP was about 0.055. Moreover, for miniaturization a U type expander was tested and the performance is about 10 % less than that of an In-line type expander. After that, we have estimated that the cooling performance is influenced by the environment such as the effect of the pulse-tube inclination, the temperature and the flowing quantity of cooling water. The detailed results are reported in this paper.

  9. Application of smart structure concepts to vibration suppression of a cryocooler coldfinger

    International Nuclear Information System (INIS)

    Glaser, R.J.; Kuo, Chinpo, Garba, J.A.

    1993-01-01

    A flight experiment demonstrating vibration suppression using smart structure technology is being flown on a small British satellite in late 1993. Piezo actuators are used to suppress motion of the tip of a cryocooler coldfinger in three dimensions. Two actuation methods are being demonstrated: low voltage piezo translators and applique ceramics. The applique ceramics stretch the coldfinger to cancel the tip motion and is discussed in detail in a companion paper. Commercially available piezo translators displace the entire cryocooler to cancel the motion of the tip of the coldfinger as measured by three eddy current transducers. Two types of control systems are being demonstrated: a real time analog control system using position feedback, and a digital feed forward controller that updates it's waveform every second or so. The flight experiment is a technology demonstration. The coldfinger is not being used to cool an operational sensor. Instead, the cooler vibration experiment will demonstrate that this class of hardware can be flown successfully. This includes qualification of the piezos for launch, and for the space environment; the design and qualification of low-power flight piezo drivers; and design and implementation of the control systems

  10. New application of plate-fin heat exchanger with regenerative cryocoolers

    Science.gov (United States)

    Chang, Ho-Myung; Gwak, Kyung Hyun

    2015-09-01

    A design idea is newly proposed and investigated for the application of plate-fin heat exchanger (PFHX) with regenerative cryocoolers. The role of this heat exchanger is to effectively absorb heat from the stream of coolant and deliver it to the cold-head of a cryocooler. While various types of tubular HX's have been developed so far, a small PFHX could be more useful for this purpose by taking advantage of compactness and design flexibility. In order to confirm the feasibility and effectiveness, a prototype of aluminum-brazed PFHX is designed, fabricated, and tested with a single-stage GM cryocooler in experiments for subcooling liquid nitrogen from 78 K to 65-70 K. The results show that the PFHX is 30-50% more effective in cooling rate than the tubular HX's. Several potential applications of PFHX are presented and discussed with specific design concepts.

  11. Design and test of the Stirling-type pulse tube cryocooler

    Science.gov (United States)

    Hong, Yong-Ju; Ko, Junseok; Kim, Hyo-Bong; Yeom, Han-Kil; In, Sehwan; Park, Seong-Je

    2017-12-01

    Stirling type pulse tube cryocoolers are very attractive for cooling of diverse application because it has it has several inherent advantages such as no moving part in the cold end, low manufacturing cost and long operation life. To develop the Stirling-type pulse tube cryocooler, we need to design a linear compressor to drive the pulse tube cryocooler. A moving magnet type linear motor of dual piston configuration is designed and fabricated, and this compressor could be operated with the electric power of 100 W and the frequency up to 60 Hz. A single stage coaxial type pulse tube cold finger aiming at over 1.5 W at 80K is built and tested with the linear compressor. Experimental investigations have been conducted to evaluate their performance characteristics with respect to several parameters such as the phase shifter, the charging pressure and the operating frequency of the linear compressor.

  12. Dynamic Simulation of a Periodic 10 K Sorption Cryocooler

    Science.gov (United States)

    Bhandari, P.; Rodriguez, J.; Bard, S.; Wade, L.

    1994-01-01

    A transient thermal simulation model has been developed to simulate the dynamic performance of a multiple-stage 10 K sorption cryocooler for spacecraft sensor cooling applications that require periodic quick-cooldown (under 2 minutes) , negligible vibration, low power consumption, and long life (5 to 10 years). The model was specifically designed to represent the Brilliant Eyes Ten-Kelvin Sorption Cryocooler Experiment (BETSCE), but it can be adapted to represent other sorption cryocooler systems as well. The model simulates the heat transfer, mass transfer, and thermodynamic processes in the cryostat and the sorbent beds for the entire refrigeration cycle, and includes the transient effects of variable hydrogen supply pressures due to expansion and overflow of hydrogen during the cooldown operation. The paper describes model limitations and simplifying assumptions, with estimates of errors induced by them, and presents comparisons of performance predictions with ground experiments. An important benefit of the model is its ability to predict performance sensitivities to variations of key design and operational parameters. The insights thus obtained are expected to lead to higher efficiencies and lower weights for future designs.

  13. Temperature oscillation suppression of GM cryocooler

    Science.gov (United States)

    Okidono, K.; Oota, T.; Kurihara, H.; Sumida, T.; Nishioka, T.; Kato, H.; Matsumura, M.; Sasaki, O.

    2012-12-01

    GM cryocooler is a convenient refrigerator to achieve low temperatures about 4 K, while it is not suitable for precise measurements because of the large temperature oscillation of typically about 0.3 K. To resolve this problem, we have developed an adapter (He-pot) with a simple structure as possible. From the thermodynamic consideration, both heat capacity and thermal conductance should be large in order to reduce the temperature oscillation without compromising cooling power. Optimal structure of the He-pot is a copper cylinder filled with high pressure He-gas at room temperature. This can reduce the temperature oscillation to less than 10 mK below a certain temperature TH without compromising cooling power. TH are 3.8 and 4.5 for filled He-gas pressures of 90 and 60 atm, respectively. By using this He-pot, GM cryocooler can be applied to such as precise physical property measurements and THz detection.

  14. Recent development status of compact 2 K GM cryocoolers

    Science.gov (United States)

    Bao, Q.; Xu, M. Y.; Tsuchiya, A.; Li, R.

    2015-12-01

    To meet the growing demand for a compact cooling solution for superconducting electronic devices, we developed a two-stage 2 K GM cryocooler and a cryostat system, which can reach 46.3 K / 2.2 K on the first and second stages under no-load conditions. Nevertheless, with several innovative technologies applied, the total length of the expander cylinder is reduced to under 70% of the smallest conventional 4 K GM cryocooler. In this paper we will present the design method, including material selection and structure design with detailed explanation, which has been confirmed by both simulation and experiment.

  15. Small high cooling power space cooler

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, T. V.; Raab, J.; Durand, D.; Tward, E. [Northrop Grumman Aerospace Systems Redondo Beach, Ca, 90278 (United States)

    2014-01-29

    The small High Efficiency pulse tube Cooler (HEC) cooler, that has been produced and flown on a number of space infrared instruments, was originally designed to provide cooling of 10 W @ 95 K. It achieved its goal with >50% margin when limited by the 180 W output ac power of its flight electronics. It has also been produced in 2 stage configurations, typically for simultaneously cooling of focal planes to temperatures as low as 35 K and optics at higher temperatures. The need for even higher cooling power in such a low mass cryocooler is motivated by the advent of large focal plane arrays. With the current availability at NGAS of much larger power cryocooler flight electronics, reliable long term operation in space with much larger cooling powers is now possible with the flight proven 4 kg HEC mechanical cooler. Even though the single stage cooler design can be re-qualified for those larger input powers without design change, we redesigned both the linear and coaxial version passive pulse tube cold heads to re-optimize them for high power cooling at temperatures above 130 K while rejecting heat to 300 K. Small changes to the regenerator packing, the re-optimization of the tuned inertance and no change to the compressor resulted in the increased performance at 150 K. The cooler operating at 290 W input power achieves 35 W@ 150 K corresponding to a specific cooling power at 150 K of 8.25 W/W and a very high specific power of 72.5 W/Kg. At these powers the cooler still maintains large stroke, thermal and current margins. In this paper we will present the measured data and the changes to this flight proven cooler that were made to achieve this increased performance.

  16. High-resolution X-ray crystal structure of bovine H-protein using the high-pressure cryocooling method.

    Science.gov (United States)

    Higashiura, Akifumi; Ohta, Kazunori; Masaki, Mika; Sato, Masaru; Inaka, Koji; Tanaka, Hiroaki; Nakagawa, Atsushi

    2013-11-01

    Recently, many technical improvements in macromolecular X-ray crystallography have increased the number of structures deposited in the Protein Data Bank and improved the resolution limit of protein structures. Almost all high-resolution structures have been determined using a synchrotron radiation source in conjunction with cryocooling techniques, which are required in order to minimize radiation damage. However, optimization of cryoprotectant conditions is a time-consuming and difficult step. To overcome this problem, the high-pressure cryocooling method was developed (Kim et al., 2005) and successfully applied to many protein-structure analyses. In this report, using the high-pressure cryocooling method, the X-ray crystal structure of bovine H-protein was determined at 0.86 Å resolution. Structural comparisons between high- and ambient-pressure cryocooled crystals at ultra-high resolution illustrate the versatility of this technique. This is the first ultra-high-resolution X-ray structure obtained using the high-pressure cryocooling method.

  17. Miniature PT Cryocooler Activated by Resonant Piezoelectric Compressor and Passive Warm Expander

    Science.gov (United States)

    Sobol, S.; Grossman, G.

    2017-12-01

    A novel type of PZT-based compressor operating at mechanical resonance, suitable for pneumatically-driven Stirling-type cryocoolers, was presented at CEC-ICMC 2015. The detailed concept, analytical model and the test results on the preliminary prototype were reported earlier and presented at ICC17. Despite some mismatch between the impedances and insufficient structural stiffness, this compressor demonstrated the feasibility to drive our miniature Pulse Tube cryocooler MTSa, operating at 103 Hz and requiring an average PV power of 11 W, filling pressure of 40 Bar and a pressure ratio of 1.3. At ICC19 the prototype of a miniature passive warm expander (WE) was presented. The WE mechanism included a phase shifting piston suspended on a silicone diaphragm, a mass element, and a viscous damping system. Several technical drawbacks prevented perfect matching between the WE and MTSa; however, the presented prototype proved the ability to create any flow-to-pressure phase appropriate for a PT cryocooler. This paper concentrates on integration of the MTSa cryocooler with the recently modified PZT compressor operating at corrected mechanical resonance and the modified WE, which was also updated recently to match the MTSa requirements.

  18. Role of size on the relative importance of fluid dynamic losses in linear cryocoolers

    Science.gov (United States)

    Kirkconnell, Carl; Ghavami, Ali; Ghiaasiaan, S. Mostafa; Perrella, Matthew

    2017-12-01

    Thermodynamic modeling results for a novel small satellite (SmallSat) Stirling Cryocooler, capable of delivering over 200 mW net cooling power at 80 K for less than 6 W DC input power, are used in this paper as the basis for related pulse tube computational fluid dynamics (CFD) analysis. Industry and government requirements for SmallSat infrared sensors are driving the development of ever-more miniaturized cryocooler systems. Such cryocoolers must be extremely compact and lightweight, a challenge met by this research team through operating a Stirling cryocooler at a frequency of approximately 300 Hz. The primary advantage of operating at such a high frequency is that the required compression and expansion swept volumes are reduced relative to linear coolers operating at lower frequencies, which evidently reduces the size of the motor mechanisms and the thermodynamic components. In the case of a pulse tube cryocooler, this includes a reduction in diameter of the pulse tube itself. This unfortunately leads to high boundary layer losses, as the presented results demonstrate. Using a Stirling approach with a mechanical moving expander piston eliminates this small pulse tube loss mechanism, but other challenges are introduced, such as maintaining very tight clearance gaps between moving and stationary elements. This paper focuses on CFD modelling results for a highly miniaturized pulse tube cooler.

  19. Automated Cryocooler Monitor and Control System Software

    Science.gov (United States)

    Britchcliffe, Michael J.; Conroy, Bruce L.; Anderson, Paul E.; Wilson, Ahmad

    2011-01-01

    This software is used in an automated cryogenic control system developed to monitor and control the operation of small-scale cryocoolers. The system was designed to automate the cryogenically cooled low-noise amplifier system described in "Automated Cryocooler Monitor and Control System" (NPO-47246), NASA Tech Briefs, Vol. 35, No. 5 (May 2011), page 7a. The software contains algorithms necessary to convert non-linear output voltages from the cryogenic diode-type thermometers and vacuum pressure and helium pressure sensors, to temperature and pressure units. The control function algorithms use the monitor data to control the cooler power, vacuum solenoid, vacuum pump, and electrical warm-up heaters. The control algorithms are based on a rule-based system that activates the required device based on the operating mode. The external interface is Web-based. It acts as a Web server, providing pages for monitor, control, and configuration. No client software from the external user is required.

  20. An experimental study for the phase shift between piston and displacer in the Stirling cryocooler

    International Nuclear Information System (INIS)

    Park, S. J.; Hong, Y. J.; Kim, H. B.; Son, H. K.; Yu, B. K.

    2002-01-01

    The small cryocooler is being widely applied to the areas of infrared detector, superconductor filter, satellite communication, and cryopump. The cryocooler working on the Stirling cycle are characterized by small size, lightweight, low power consumption and high reliability. For these reasons, FPFD (Free Piston Free Displacer) Stirling cryocooler is widely used not only tactical infrared imaging camera but also medical diagnostic apparatus. In this study, Stirling cryocooler actuated by the dual linear motor is designed and manufactured. And, displacement of the piston is measured by LVDTs (Linear Variable Differential Transformers), displacement of the displacer is measured by laser optic method, and phase shift between piston and displacer is discussed. Finally, when the phase shift between displacements of the piston and displacer is 45 .deg., operating frequency is optimum and is decided by resonant frequency of the expander, mass and cross section area of the displacer and constant by friction and flow resistance

  1. An experimental study for the phase shift between piston and displacer in the Stirling cryocooler

    Energy Technology Data Exchange (ETDEWEB)

    Park, S. J.; Hong, Y. J.; Kim, H. B. [Korea Institute of Machinery and Materials, Taejon (Korea, Republic of); Son, H. K.; Yu, B. K. [Wooyoung Co., Ltd., Seoul (Korea, Republic of)

    2002-07-01

    The small cryocooler is being widely applied to the areas of infrared detector, superconductor filter, satellite communication, and cryopump. The cryocooler working on the Stirling cycle are characterized by small size, lightweight, low power consumption and high reliability. For these reasons, FPFD (Free Piston Free Displacer) Stirling cryocooler is widely used not only tactical infrared imaging camera but also medical diagnostic apparatus. In this study, Stirling cryocooler actuated by the dual linear motor is designed and manufactured. And, displacement of the piston is measured by LVDTs (Linear Variable Differential Transformers), displacement of the displacer is measured by laser optic method, and phase shift between piston and displacer is discussed. Finally, when the phase shift between displacements of the piston and displacer is 45 .deg., operating frequency is optimum and is decided by resonant frequency of the expander, mass and cross section area of the displacer and constant by friction and flow resistance.

  2. Cryocooled superconducting magnets for high magnetic fields at the HFLSM and future collaboration with the TML

    International Nuclear Information System (INIS)

    Watanabe, K; Nishijima, G; Awaji, S; Koyama, K; Takahashi, K; Kobayashi, N; Kiyoshi, T

    2006-01-01

    A hybrid magnet needs a large amount of liquid helium for operation. In order to make an easy-to-operate hybrid magnet system, we constructed a cryocooled 28 T hybrid magnet, consisting of an outer cryocooled 10 T superconducting magnet and an inner traditional water-cooled 19 T resistive magnet. As a performance test, the cryocooled hybrid magnet generated 27.5 T in a 32 mm room temperature experimental bore. As long as Nb3Sn superconducting wires are employed, the expected maximum high field generation in the cryocooled superconducting magnet will be 17 T at 5 K. We adopted the high temperature superconducting insert coil, employing Ag-sheathed Bi 2 Sr 2 Ca 2 Cu 3 O 10 superconducting tape. In combination with the low temperature 16.5 T back-up coil with a 174 mm cold bore, the cryocooled high temperature superconducting magnet successfully generated the total central field of 18.1 T in a 52 mm room temperature bore. As a next step, we start the collaboration with the National Institute for Materials Science for the new developmental works of a 30 T high temperature superconducting magnet and a 50 T-class hybrid magnet

  3. 14 CFR 1214.1104 - Evaluation and ranking of highly qualified candidates.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Evaluation and ranking of highly qualified candidates. 1214.1104 Section 1214.1104 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... ranking of highly qualified candidates. (a) A selection board consisting of discipline experts, and such...

  4. Development of a miniature Stirling cryocooler for LWIR small satellite applications

    Science.gov (United States)

    Kirkconnell, C. S.; Hon, R. C.; Perella, M. D.; Crittenden, T. M.; Ghiaasiaan, S. M.

    2017-05-01

    The optimum small satellite (SmallSat) cryocooler system must be extremely compact and lightweight, achieved in this paper by operating a linear cryocooler at a frequency of approximately 300 Hz. Operation at this frequency, which is well in excess of the 100-150 Hz reported in recent papers on related efforts, requires an evolution beyond the traditional Oxford-class, flexure-based methods of setting the mechanical resonance. A novel approach that optimizes the electromagnetic design and the mechanical design together to simultaneously achieve the required dynamic and thermodynamic performances is described. Since highly miniaturized pulse tube coolers are fundamentally ill-suited for the sub-80K temperature range of interest because the boundary layer losses inside the pulse tube become dominant at the associated very small pulse tube size, a moving displacer Stirling cryocooler architecture is used. Compact compressor mechanisms developed on a previous program are reused for this design, and they have been adapted to yield an extremely compact Stirling warm end motor mechanism. Supporting thermodynamic and electromagnetic analysis results are reported.

  5. Engineering model cryocooler test results

    International Nuclear Information System (INIS)

    Skimko, M.A.; Stacy, W.D.; McCormick, J.A.

    1992-01-01

    This paper reports that recent testing of diaphragm-defined, Stirling-cycle machines and components has demonstrated cooling performance potential, validated the design code, and confirmed several critical operating characteristics. A breadboard cryocooler was rebuilt and tested from cryogenic to near-ambient cold end temperatures. There was a significant increase in capacity at cryogenic temperatures and the performance results compared will with code predictions at all temperatures. Further testing on a breadboard diaphragm compressor validated the calculated requirement for a minimum axial clearance between diaphragms and mating heads

  6. Jet Propulsion Laboratory/NASA Lewis Research Center space qualified hybrid high temperature superconducting/semiconducting 7.4 GHz low-noise downconverter for NRL HTSSE-II program

    International Nuclear Information System (INIS)

    Javadi, H.H.S.; Bowen, J.G.; Rascoe, D.L.; Chorey, C.M.

    1996-01-01

    A deep space satellite downconverter receiver was proposed by Jet Propulsion Laboratory (JPL) and NASA Lewis Research Center (LeRC) for the Naval Research Laboratory's (NRL) high temperature superconductivity space experiment, phase-II (HTSSE-II) program. Space qualified low-noise cryogenic downconverter receivers utilizing thin-film high temperature superconducting (HTS) passive circuitry and semiconductor active devices were developed and delivered to NRL. The downconverter consists of an HTS preselect filter, a cryogenic low-noise amplifier, a cryogenic mixer, and a cryogenic oscillator with an HTS resonator. HTS components were inserted as the front-end filter and the local oscillator resonator for their superior 77 K performance over the conventional components. The semiconducting low noise amplifier also benefited from cooling to 77 K. The mixer was designed specifically for cryogenic applications and provided low conversion loss and low power consumption. In addition to an engineering model, two space qualified units (qualification, flight) were built and delivered to NRL. Manufacturing, integration and test of the space qualified downconverters adhered to the requirements of JPL class-D space instruments and partially to MIL-STD-883D specifications. The qualification unit has ∼50 K system noise temperature which is a factor of three better than a conventional downconverter at room temperature

  7. Multimodal tuned dynamic absorber for split Stirling linear cryocooler

    Science.gov (United States)

    Veprik, A.; Tuito, A.

    2017-02-01

    Forthcoming low size, weight, power and price split Stirling linear cryocoolers may rely on electro-dynamically driven single-piston compressors and pneumatically driven expanders interconnected by the configurable transfer line. For compactness, compressor and expander units may be placed in a side-by-side manner, thus producing tonal vibration export comprising force and moment components. In vibration sensitive applications, this may result in excessive angular line of sight jitter and translational defocusing affecting the image quality. The authors present Multimodal Tuned Dynamic Absorber (MTDA), having one translational and two tilting modes essentially tuned to the driving frequency. The dynamic reactions (force and moment) produced by such a MTDA are simultaneously counterbalancing force and moment vibration export produced by the cryocooler. The authors reveal the design details, the method of fine modal tuning and outcomes of numerical simulation on attainable performance.

  8. Study on a high capacity two-stage free piston Stirling cryocooler working around 30 K

    Science.gov (United States)

    Wang, Xiaotao; Zhu, Jian; Chen, Shuai; Dai, Wei; Li, Ke; Pang, Xiaomin; Yu, Guoyao; Luo, Ercang

    2016-12-01

    This paper presents a two-stage high-capacity free-piston Stirling cryocooler driven by a linear compressor to meet the requirement of the high temperature superconductor (HTS) motor applications. The cryocooler system comprises a single piston linear compressor, a two-stage free piston Stirling cryocooler and a passive oscillator. A single stepped displacer configuration was adopted. A numerical model based on the thermoacoustic theory was used to optimize the system operating and structure parameters. Distributions of pressure wave, phase differences between the pressure wave and the volume flow rate and different energy flows are presented for a better understanding of the system. Some characterizing experimental results are presented. Thus far, the cryocooler has reached a lowest cold-head temperature of 27.6 K and achieved a cooling power of 78 W at 40 K with an input electric power of 3.2 kW, which indicates a relative Carnot efficiency of 14.8%. When the cold-head temperature increased to 77 K, the cooling power reached 284 W with a relative Carnot efficiency of 25.9%. The influences of different parameters such as mean pressure, input electric power and cold-head temperature are also investigated.

  9. Investigation of pressure drop in capillary tube for mixed refrigerant Joule-Thomson cryocooler

    International Nuclear Information System (INIS)

    Ardhapurkar, P. M.; Sridharan, Arunkumar; Atrey, M. D.

    2014-01-01

    A capillary tube is commonly used in small capacity refrigeration and air-conditioning systems. It is also a preferred expansion device in mixed refrigerant Joule-Thomson (MR J-T) cryocoolers, since it is inexpensive and simple in configuration. However, the flow inside a capillary tube is complex, since flashing process that occurs in case of refrigeration and air-conditioning systems is metastable. A mixture of refrigerants such as nitrogen, methane, ethane, propane and iso-butane expands below its inversion temperature in the capillary tube of MR J-T cryocooler and reaches cryogenic temperature. The mass flow rate of refrigerant mixture circulating through capillary tube depends on the pressure difference across it. There are many empirical correlations which predict pressure drop across the capillary tube. However, they have not been tested for refrigerant mixtures and for operating conditions of the cryocooler. The present paper assesses the existing empirical correlations for predicting overall pressure drop across the capillary tube for the MR J-T cryocooler. The empirical correlations refer to homogeneous as well as separated flow models. Experiments are carried out to measure the overall pressure drop across the capillary tube for the cooler. Three different compositions of refrigerant mixture are used to study the pressure drop variations. The predicted overall pressure drop across the capillary tube is compared with the experimentally obtained value. The predictions obtained using homogeneous model show better match with the experimental results compared to separated flow models

  10. A miniature pulse tube cryocooler used in a superspectral imager

    Science.gov (United States)

    Jiang, Zhenhua; Wu, Yinong

    2017-05-01

    In this paper, we describe a hihg0 frequency pulse tube cryocooler used in a superspectral imager to be launched in 2020. The superspectral imager is a field-dividing optical imaging system and uses 14 sets of integrated IR detector cryocooler dewar assembly. For the requirements of less heat loss an smaller size, each set is highly integrated by directly mounting the IR dectector's sapphire substrate on the pulse tube's cold tip, and welding the dewar's housing to the flange of the cold finger. Driven by a pair of moving magnet linear motors, the dual-opposed piston compressor of the croycooler is running at 120Hz. Filled with customized stainless screens in the regenerator, the cryolooler reaches 8.1% carnot efficiency at the cooling power of 1W@80K with 34Wac input power.

  11. Large-Scale Demonstration of Liquid Hydrogen Storage with Zero Boiloff for In-Space Applications

    Science.gov (United States)

    Hastings, L. J.; Bryant, C. B.; Flachbart, R. H.; Holt, K. A.; Johnson, E.; Hedayat, A.; Hipp, B.; Plachta, D. W.

    2010-01-01

    Cryocooler and passive insulation technology advances have substantially improved prospects for zero-boiloff cryogenic storage. Therefore, a cooperative effort by NASA s Ames Research Center, Glenn Research Center, and Marshall Space Flight Center (MSFC) was implemented to develop zero-boiloff concepts for in-space cryogenic storage. Described herein is one program element - a large-scale, zero-boiloff demonstration using the MSFC multipurpose hydrogen test bed (MHTB). A commercial cryocooler was interfaced with an existing MHTB spray bar mixer and insulation system in a manner that enabled a balance between incoming and extracted thermal energy.

  12. A pulse tube cryocooler with a cold reservoir

    Science.gov (United States)

    Zhang, X. B.; Zhang, K. H.; Qiu, L. M.; Gan, Z. H.; Shen, X.; Xiang, S. J.

    2013-02-01

    Phase difference between pressure wave and mass flow is decisive to the cooling capacity of regenerative cryocoolers. Unlike the direct phase shifting using a piston or displacer in conventional Stirling or GM cryocoolers, the pulse tube cyocooler (PTC) indirectly adjusts the cold phase due to the absence of moving parts at the cold end. The present paper proposed and validated theoretically and experimentally a novel configuration of PTC, termed cold reservoir PTC, in which a reservoir together with an adjustable orifice is connected to the cold end of the pulse tube. The impedance from the additional orifice to the cold end helps to increase the mass flow in phase with the pressure wave at the cold end. Theoretical analyses with the linear model for the orifice and double-inlet PTCs indicate that the cooling performance can be improved by introducing the cold reservoir. The preliminary experiments with a home-made single-stage GM PTC further validated the results on the premise of minor opening of the cold-end orifice.

  13. RMs1: qualification results of the rotary miniature Stirling cryocooler at Thales Cryogenics

    Science.gov (United States)

    Martin, Jean-Yves; Seguineau, Cédric; Van-Acker, Sébastien; Sacau, Mikel; Le Bordays, Julien; Etchanchu, Thierry; Vasse, Christophe; Abadie, Christian; Laplagne, Gilles; Benschop, Tonny

    2017-05-01

    The trend for miniaturized Integrated Dewar and Cooler Assemblies (IDCA) has been confirmed over the past few years with several mentions of a new generation of IR detector working at High Operating Temperature (HOT). This key technology enables the use of cryocooler with reduced needs of cryogenics power. As a consequence, miniaturized IDCA are the combination of a HOT IR detector coupled with a low-size, low-weight and low-power (SWaP) cryocooler. Thales Cryogenics has developed his own line of SWaP products. Qualification results on linear solution where shown last year. The current paper focuses on the latest results obtained on RMs1 prototypes, the new rotary SWaP cryocooler from Thales Cryogenics. Cryogenic performances and induced vibrations are presented. In a second part, progress is discussed on compactness and weight on one side, and on power consumption on the other side. It shows how the trade-off made between weight and power consumption could lead to an optimized solution at system level. At least, an update is made on the qualification status.

  14. Optimized autonomous operations of a 20 K space hydrogen sorption cryocooler

    Science.gov (United States)

    Borders, J.; Morgante, G.; Prina, M.; Pearson, D.; Bhandari, P.

    2004-06-01

    A fully redundant hydrogen sorption cryocooler is being developed for the European Space Agency Planck mission, dedicated to the measurement of the temperature anisotropies of the cosmic microwave background radiation with unprecedented sensitivity and resolution [Advances in Cryogenic Engineering 45A (2000) 499]. In order to achieve this ambitious scientific task, this cooler is required to provide a stable temperature reference (˜20 K) and appropriate cooling (˜1 W) to the two instruments on-board, with a flight operational lifetime of 18 months. During mission operations, communication with the spacecraft will be possible in a restricted time-window, not longer than 2 h/day. This implies the need for an operations control structure with the required robustness to safely perform autonomous procedures. The cooler performance depends on many operating parameters (such as the temperatures of the pre-cooling stages and the warm radiator), therefore the operation control system needs the capability to adapt to variations of these boundary conditions, while maintaining safe operating procedures. An engineering bread board (EBB) cooler was assembled and tested to evaluate the behavior of the system under conditions simulating flight operations and the test data were used to refine and improve the operation control software. In order to minimize scientific data loss, the cooler is required to detect all possible failure modes and to autonomously react to them by taking the appropriate action in a rapid fashion. Various procedures and schemes both general and specific in nature were developed, tested and implemented to achieve these goals. In general, the robustness to malfunctions was increased by implementing an automatic classification of anomalies in different levels relative to the seriousness of the error. The response is therefore proportional to the failure level. Specifically, the start-up sequence duration was significantly reduced, allowing a much faster

  15. Air liquide's space pulse tube cryocooler systems

    Science.gov (United States)

    Trollier, T.; Tanchon, J.; Buquet, J.; Ravex, A.

    2017-11-01

    Thanks to important development efforts completed with ESA funding, Air Liquide Advanced Technology Division (AL/DTA), is now in position to propose two Pulse Tube cooler systems in the 40-80K temperature range for coming Earth Observation missions such as Meteosat Third Generation (MTG), SIFTI, etc… The Miniature Pulse Tube Cooler (MPTC) is lifting up to 2.47W@80K with 50W compressor input power and 10°C rejection temperature. The weight is 2.8 kg. The Large Pulse Tube Cooler (LPTC) is providing 2.3W@50K for 160W input power and 10°C rejection temperature. This product is weighing 5.1 kg. The two pulse tube coolers thermo-mechanical units are qualified against environmental constraints as per ECSS-E-30. They are both using dual opposed pistons flexure bearing compressor with moving magnet linear motors in order to ensure very high lifetime. The associated Cooler Drive Electronics is also an important aspect specifically regarding the active control of the cooler thermo-mechanical unit during the launch phase and the active reduction of the vibrations induced by the compressor (partly supported by the French Agency CNES). This paper details the presentation of the two Pulse Tube Coolers together with the Cooler Drive Electronics aspects.

  16. Applications concepts of small regenerative cryocoolers in superconducitng magnet systems

    NARCIS (Netherlands)

    van der Laan, M.T.G.; van der Laan, M.T.G.; Tax, R.B.; ten Kate, Herman H.J.

    1992-01-01

    Superconducting magnets are in growing use outside laboratories for example MRI scanners in hospitals. Other applications under development are magnet systems for separation, levitated trains and ship propulsion. The application of cryocoolers can make these systems more practical. Interfacing these

  17. Building the better cryocooler

    International Nuclear Information System (INIS)

    Radebaugh, R.

    1992-01-01

    This article focuses on the present and future status of small cryocoolers that may be useful for cooling superconducting electronics or magnets no larger than those of Magnetic Resonance Imaging (MRI) systems. In a few cases superconductors have found their way into a large market. The best example is superconducting Super Collider (SSC) and other accelerators use an enormous amount of superconducting wire and require large liquid helium plants for cooling. The costs of these large accelerator systems greatly restricts the number of such installations. Thin film superconducting electronic devices have the potential of being made relatively inexpensively and have a performance advantage over conventional electronic systems. The possible market size for superconducting electronics could be extremely large is one serious problem would simply disappear

  18. Thermal properties of a large-bore cryocooled 10 T superconducting magnet for a hybrid magnet

    International Nuclear Information System (INIS)

    Ishizuka, M.; Hamajima, T.; Itou, T.; Sakuraba, J.; Nishijima, G.; Awaji, S.; Watanabe, K.

    2010-01-01

    A cryocooled 10 T superconducting magnet with a 360 mm room temperature bore has been developed for a hybrid magnet. The superconducting magnet cooled by four Gifford-McMahon cryocoolers has been designed to generate a magnetic field of 10 T. Since superconducting wires composed of coils were subjected to large hoop stress over 150 MPa and Nb 3 Sn superconducting wires particularly showed a low mechanical strength due to those brittle property, Nb 3 Sn wires strengthened by NbTi-filaments were developed for the cryocooled superconducting magnet. We have already reported that the hybrid magnet could generate the resultant magnetic field of 27.5 T by adding 8.5 T from the superconducting magnet and 19 T from a water-cooled Bitter resistive magnet, after the water-cooled resistive magnet was inserted into the 360 mm room temperature bore of the cryocooled superconducting magnet. When the hybrid magnet generated the field of 27.5 T, it achieved the high magnetic-force field (B x ∂Bz/∂z) of 4500 T 2 /m, which was useful for magneto-science in high fields such as materials levitation research. In this paper, we particularly focus on the cause that the cryocooled superconducting magnet was limited to generate the designed magnetic field of 10 T in the hybrid magnet operation. As a result, it was found that there existed mainly two causes as the limitation of the magnetic field generation. One was a decrease of thermal conductive passes due to exfoliation from the coil bobbin of the cooling flange. The other was large AC loss due to both a thick Nb 3 Sn layer and its large diameter formed on Nb-barrier component in Nb 3 Sn wires.

  19. Study Behaviors and USMLE Step 1 Performance: Implications of a Student Self-Directed Parallel Curriculum.

    Science.gov (United States)

    Burk-Rafel, Jesse; Santen, Sally A; Purkiss, Joel

    2017-11-01

    To determine medical students' study behaviors when preparing for the United States Medical Licensing Examination (USMLE) Step 1, and how these behaviors are associated with Step 1 scores when controlling for likely covariates. The authors distributed a study-behaviors survey in 2014 and 2015 at their institution to two cohorts of medical students who had recently taken Step 1. Demographic and academic data were linked to responses. Descriptive statistics, bivariate correlations, and multiple linear regression analyses were performed. Of 332 medical students, 274 (82.5%) participated. Most students (n = 211; 77.0%) began studying for Step 1 during their preclinical curriculum, increasing their intensity during a protected study period during which they averaged 11.0 hours studying per day (standard deviation [SD] 2.1) over a period of 35.3 days (SD 6.2). Students used numerous third-party resources, including reading an exam-specific 700-page review book on average 2.1 times (SD 0.8) and completing an average of 3,597 practice multiple-choice questions (SD 1,611). Initiating study prior to the designated study period, increased review book usage, and attempting more practice questions were all associated with higher Step 1 scores, even when controlling for Medical College Admission Test scores, preclinical exam performance, and self-identified score goal (adjusted R = 0.56, P < .001). Medical students at one public institution engaged in a self-directed, "parallel" Step 1 curriculum using third-party study resources. Several study behaviors were associated with improved USMLE Step 1 performance, informing both institutional- and student-directed preparation for this high-stakes exam.

  20. Thermodynamic design of 10 kW Brayton cryocooler for HTS cable

    Science.gov (United States)

    Chang, Ho-Myung; Park, C. W.; Yang, H. S.; Sohn, Song Ho; Lim, Ji Hyun; Oh, S. R.; Hwang, Si Dole

    2012-06-01

    Thermodynamic design of Brayton cryocooler is presented as part of an ongoing governmental project in Korea, aiming at 1 km HTS power cable in the transmission grid. The refrigeration requirement is 10 kW for continuously sub-cooling liquid nitrogen from 72 K to 65 K. An ideal Brayton cycle for this application is first investigated to examine the fundamental features. Then a practical cycle for a Brayton cryocooler is designed, taking into account the performance of compressor, expander, and heat exchangers. Commercial software (Aspen HYSYS) is used for simulating the refrigeration cycle with real fluid properties of refrigerant. Helium is selected as a refrigerant, as it is superior to neon in thermodynamic efficiency. The operating pressure and flow rate of refrigerant are decided with a constraint to avoid the freezing of liquid nitrogen

  1. ISS qualified thermal carrier equipment

    Science.gov (United States)

    Deuser, Mark S.; Vellinger, John C.; Jennings, Wm. M.

    2000-01-01

    Biotechnology is undergoing a period of rapid and sustained growth, a trend which is expected to continue as the general population ages and as new medical treatments and products are conceived. As pharmaceutical and biomedical companies continue to search for improved methods of production and, for answers to basic research questions, they will seek out new avenues of research. Space processing on the International Space Station (ISS) offers such an opportunity! Space is rapidly becoming an industrial laboratory for biotechnology research and processing. Space bioprocessing offers exciting possibilities for developing new pharmaceuticals and medical treatments, which can be used to benefit mankind on Earth. It also represents a new economic frontier for the private sector. For over eight years, the thermal carrier development team at SHOT has been working with government and commercial sector scientists who are conducting microgravity experiments that require thermal control. SHOT realized several years ago that the hardware currently being used for microgravity thermal control was becoming obsolete. It is likely that the government, academic, and industrial bioscience community members could utilize SHOT's hardware as a replacement to their current microgravity thermal carrier equipment. Moreover, SHOT is aware of several international scientists interested in utilizing our space qualified thermal carrier. SHOT's economic financing concept could be extremely beneficial to the international participant, while providing a source of geographic return for their particular region. Beginning in 2000, flight qualified thermal carriers are expected to be available to both the private and government sectors. .

  2. Theoretical study of effect of working fluid on the performance of 77–100 K adsorption cryocooler

    International Nuclear Information System (INIS)

    Luo, B.J.; Wang, Z.L.; Yan, T.; Hong, G.T.; Li, Y.L.; Liang, J.T.

    2015-01-01

    Highlights: • Investigate the effects of nitrogen, argon and oxygen on the performance of adsorption cryocooler in the range 77–100 K. • A model of adsorption compressor with a two-stage adsorption compressor is constructed and optimized with genetic algorithm. • Working fluid has larger effects on the adsorption compressor than on the cold stage. • The best selection of working fluid depends on the operating parameters. - Abstract: The aim of this study is to investigate the effects of working fluid (nitrogen, argon and oxygen) on the performance of adsorption cryocooler in the range 77–100 K. A thermodynamic model of adsorption cryocooler with two-stage compressor has been constructed. The model is based on quasi-static conditions without considering the temperature profiles and pressure drops across the compressor. It is then analyzed with an optimization toolbox to determine the optimum operating conditions to obtain the optimum performance of adsorption cryocooler. The Coefficient of Performance (COP) for each working fluid in the range 77–100 K is obtained and compared. It is found that working fluid has larger effects on adsorption compressor than on cold stage, and the optimum selection of working fluid depends on the operating parameters

  3. Application of a Cryocooler in the Superconducting Magnet Cooling System

    International Nuclear Information System (INIS)

    Kowalczyk, W.; Malinowski, H.

    1998-01-01

    The application of the cryocooler working with a OGMS separator was suggested. It is very important to decrease the heat leak into the electromagnet. It was discussed how to reduce the heat leak into the separator's coils. The use of a high temperature superconducting current leads is proposed and calculated. (author)

  4. The relationship between internal medicine residency graduate performance on the ABIM certifying examination, yearly in-service training examinations, and the USMLE Step 1 examination.

    Science.gov (United States)

    Kay, Cynthia; Jackson, Jeffrey L; Frank, Michael

    2015-01-01

    To explore the relationship between United States Medical Licensing Examination (USMLE) Step 1 scores, yearly in-service training exam (ITE) scores, and passing the American Board of Internal Medicine certifying examination (ABIM-CE). The authors conducted a retrospective database review of internal medicine residents from the Medical College of Wisconsin from 2004 through 2012. Residents' USMLE Step 1, ITE, and ABIM-CE scores were extracted. Pearson rho, chi-square, and logistic regression were used to determine whether relationships existed between the scores and if Step 1 and ITE scores correlate with passing the ABIM-CE. There were 241 residents, who participated in 728 annual ITEs. There were Step 1 scores for 195 (81%) residents and ABIM-CE scores for 183 (76%). Step 1 and ABIM-CE scores had a modest correlation (rho: 0.59), as did ITE and ABIM-CE scores (rho: 0.48-0.67). Failing Step 1 or being in the bottom ITE quartile during any year of testing markedly increased likelihood of failing the boards (Step 1: relative risk [RR]: 2.4; 95% CI: 1.0-5.9; first-year residents' RR: 1.3; 95% CI: 1.0-1.6; second-year residents' RR: 1.3; 95% CI: 1.1-1.5; third-year residents' RR: 1.3; 95% CI: 1.1-1.5). USMLE Step 1 and ITE scores have a modest correlation with board scores. Failing Step 1 or scoring in the bottom quartile of the ITE increased the risk of failing the boards. What effective intervention, if any, program directors may use with at-risk residents is a question deserving further research.

  5. Estimation of Freezing Point of Hydrocarbon and Hydrofluorocarbon Mixtures for Mixed Refrigerant jt Cryocooler

    Science.gov (United States)

    Hwang, G.; Lee, J.; Jeong, S.

    2010-04-01

    Estimating the freezing point of refrigerant is an essential part in designing an MR JT (Mixed refrigerant Joule-Thomson) cryocooler to prevent itself from clogging and to operate with stability. There were researches on estimating freezing point, but some of them resulted in the wrong prediction of clogging. In this paper, the freezing point of the MR is precisely estimated with caution of clogging. The solubility of HC (hydrocarbon) and HFC (hydrofluorocarbon) mixture components are obtained with their activity coefficients, which represent the molecular interaction among the components. The freezing points of the MR JT cryocooler are systematically investigated in the operating temperature range from 70 K to 90 K.

  6. Computer analysis of an adiabatic Stirling cryocooler using a two-phase two-component working fluid

    International Nuclear Information System (INIS)

    Renfroe, D.A.; Cheung, C.M.

    1992-01-01

    This paper describes the performance and behavior of a Stirling cyrocooler incorporating a working fluid composed of helium and nitrogen. At the operating temperature of the cryocooler (80 K), the nitrogen component will condense in the freezer section. It is shown that the phase change in the working fluid increased the heat lifted for a given size and weight of machine and the coefficient of performance. The magnitude of these effects was dependent on the mass ratio of nitrogen to helium, phase angle between the compression and expansion processes, and the ratio of the compression space volume to the expansion space volume. The optimum heat lifted performance was obtained for a mass ratio of four parts of nitrogen to one part of helium, a phase angle of approximately 100 degrees, and a volume ratio of two which resulted in a heat lifted increase of 75% over the single phase, 90 degree phase angle configuration. The coefficient of performance showed a 20% improvement

  7. Deep Space Cryocooler System (DSCS), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — As NASA missions continue to extend the horizon beyond near-Earth missions, higher performance systems must evolve to address the challenges of reduced power...

  8. Numerical Simulation of Magnetic Field Effect on Cryocooler Regenerators: Temperature Distribution

    Directory of Open Access Journals (Sweden)

    Rajendra Kumar

    2017-01-01

    Full Text Available Regenerative types of cryogenic refrigerators (or cryocoolers employ magnetic intermetallic compounds of 3d and 4f elements to work well below 10 K. This paper presents the analysis of temperature distribution in regenerators of such cryocoolers under the influence of magnetic fields of 1 T, 3 T, and 4.3 T. Commercial code of finite element analysis (FEA package, ANSYS (APDL 14.5, is used to investigate the temperature distribution under above-mentioned fields. Er3Ni is selected as regenerator material and the criteria for its selection are discussed in detail. The cold end temperature is varied from 4.2 K to 10 K and hot end temperature is fixed at 20 K. The values obtained from FEA clearly show that the ineffectiveness of Er3Ni is at 8 K and 10 K at 3 T and 4.3 T.

  9. Thermal Design of a Protomodel Space Infrared Cryogenic System

    Directory of Open Access Journals (Sweden)

    Hyung Suk Yang

    2006-06-01

    Full Text Available A Protomodel Space Infrared Cryogenic System (PSICS cooled by a stirling cryocooler has been designed. The PSICS has an IR sensor inside the cold box which is cooled by a stirling cryocooler with refrigeration capacity of 500mW at 80K in a vacuum vessel. It is important to minimize the heat load so that the background thermal noise can be reduced. In order to design the cryogenic system with low heat load and to reduce the remained heat load, we have performed numerical analyses. In this paper, we present the design factors and the results obtained by the thermal analysis of the PSICS.

  10. Linear-drive cryocoolers for the Department of Defense standard advanced dewar assembly (SADA)

    Science.gov (United States)

    Tate, Garin S.

    2005-05-01

    The Standard Advanced Dewar Assembly (SADA) is the critical module in the Department of Defense (DoD) standardization of scanning second-generation thermal imaging systems. The DoD has established a family of SADAs to fulfill a range of performance requirements for various platforms. The SADA consists of the Infrared Focal Plane Array (IRFPA), Dewar, Command & Control Electronics (C&CE), and the cryogenic cooler, and is used in platforms such as the Apache helicopter, the M1A2 Abrams main battle tank, the M2 Bradley Infantry Fighting Vehicle, and the Javelin Command Launch Unit (CLU). In support of the family of SADAs, the DoD defined a complementary family of tactical linear drive cryocoolers. The Stirling cycle linear drive cryocoolers are utilized to cool the Infrared Focal Plane Arrays (IRFPAs) in the SADAs. These coolers are required to have low input power, a quick cool-down time, low vibration output, low audible noise, and a higher reliability than currently fielded rotary coolers. These coolers must also operate in a military environment with its inherent high vibration level and temperature extremes. This paper will (1) outline the characteristics of each cryocooler, (2) present the status and results of qualification tests, (3) present the status of production efforts, and (4) present the status of efforts to increase linear drive cooler reliability.

  11. Linear Resonance Compressor for Stirling-Type Cryocoolers Activated by Piezoelectric Stack-Type Elements

    International Nuclear Information System (INIS)

    Sobol, S; Grossman, G

    2015-01-01

    A novel type of a PZT- based compressor operating at mechanical resonance, suitable for pneumatically-driven Stirling-type cryocoolers was developed theoretically and built practically during this research. A resonance operation at relatively low frequency was achieved by incorporating the piezo ceramics into the moving part, and by reducing the effective piezo stiffness using hydraulic amplification. The detailed concept, analytical model and the test results of the preliminary prototype were reported earlier and presented at ICC17 [2]. A fine agreement between the simulations and experiments spurred development of the current actual compressor designed to drive a miniature Pulse Tube cryocooler, particularly our MTSa model, which operates at 103 Hz and requires an average PV power of 11 W, filling pressure of 40 Bar and a pressure ratio of 1.3. The paper concentrates on design aspects and optimization of the governing parameters. The small stroke to diameter ratio (about 1:10) allows for the use of a composite diaphragm instead of a clearance-seal piston. The motivation is to create an adequate separation between the working fluid and the buffer gas of the compressor, thus preventing possible contamination in the cryocooler. Providing efficiency and power density similar to those of conventional linear compressors, the piezo compressor may serve as a good alternative for cryogenic applications requiring extreme reliability and absence of magnetic field interference. (paper)

  12. Analysis and comparison of different phase shifters for Stirling pulse tube cryocooler

    DEFF Research Database (Denmark)

    Lei, Tian; Pfotenhauer, John M.; Zhou, Wenjie

    2016-01-01

    Investigations of phase shifters and power recovery mechanisms are of sustainable interest for developing Stirling pulse tube cryocoolers (SPTC) with higher power density, more compact design and higher efficiency. This paper investigates the phase shifting capacity and the applications of four...

  13. Thermal analysis of the cryocooled superconducting magnet for the liquid helium-free hybrid magnet

    International Nuclear Information System (INIS)

    Ishizuka, Masayuki; Hamajima, Takataro; Itou, Tomoyuki; Sakuraba, Junji; Nishijima, Gen; Awaji, Satoshi; Watanabe, Kazuo

    2010-01-01

    The liquid helium-free hybrid magnet, which consists of an outer large bore cryocooled superconducting magnet and an inner water-cooled resistive magnet, was developed for magneto-science in high fields. The characteristic features of the cryogen-free outsert superconducting magnet are described in detail in this paper. The superconducting magnet cooled by Gifford-McMahon cryocoolers, which has a 360 mm room temperature bore in diameter, was designed to generate high magnetic fields up to 10 T. The hybrid magnet has generated the magnetic field of 27.5 T by combining 8.5 T generation of the cryogen-free superconducting magnet with 19 T generation of the water-cooled resistive magnet. The superconducting magnet was composed of inner Nb 3 Sn coils and outer NbTi coils. In particular, inner Nb 3 Sn coils were wound using high-strength CuNi-NbTi/Nb 3 Sn wires in consideration of large hoop stress. Although the cryocooled outsert superconducting magnet achieved 9.5 T, we found that the outsert magnet has a thermal problem to generate the designed maximum field of 10 T in the hybrid magnet operation. This problem is associated with unexpected AC losses in Nb 3 Sn wires.

  14. The 4 K Stirling cryocooler demonstration. Final report No. 8, 1 May 1990-30 April 1992

    International Nuclear Information System (INIS)

    Stacy, W.D.

    1992-09-01

    This report briefly summarizes the results and conclusions from an SBIR program intended to demonstrate an innovative Stirling cycle cryocooler concept for efficiently lifting heat from 4 K. Refrigeration at 4 K, a temperature useful for superconductors and sensitive instruments, is beyond the reach of conventional regenerative thermodynamic cycles due to the rapid loss of regenerator matrix heat capacity at temperatures below about 20 K. To overcome this fundamental limit, the cryocooler developed under this program integrated three unique features: recuperative regeneration between the displacement gas flow streams of two independent Stirling cycles operating at a 180 degree phase angle, tailored distortion of the two expander volume waveforms from sinusoidal to perfectly match the instantaneous regenerator heat flux from the two cycles and thereby unload the regenerator, and metal diaphragm working volumes to promote near isothermal expansion and compression processes. Use of diaphragms also provides unlimited operating life potential and eliminates bearings and high precision running seals. A phase 1 proof-of-principle experiment demonstrated that counterflow regenerator operation between 77 K and 4 K increases regenerator effectiveness by minimizing metal temperature transient cycling. In phase 2, a detailed design package for a breadboard cryocooler was completed. Fabrication techniques were successfully developed for manufacturing high precision miniature parallel plate recuperators, and samples were produced and inspected. Process development for fabricating suitably flat diaphragms proved more difficult and expensive than anticipated, and construction of the cryocooler was suspended at a completion level of approximately 75%. Subsequent development efforts on other projects have successfully overcome diaphragm fabrication difficulties

  15. Impacting student anxiety for the USMLE Step 1 through process-oriented preparation

    Directory of Open Access Journals (Sweden)

    Roy E. Strowd

    2010-02-01

    Full Text Available Background: Standardized examinations are the key components of medical education. The USMLE Step 1 is the first of these important milestones. Success on this examination requires both content competency and efficient strategies for study and review. Students employ a wide variety of techniques in studying for this examination, with heavy reliance on personal study habits and advice from other students. Nevertheless, few medical curricula formally address these strategies. Methods: In response to student-generated critique at our institution, a five-part seminar series on process-oriented preparation was developed and implemented to address such concerns. The series focused on early guidance and preparation strategies for Step 1 and the many other important challenges in medical school. Emphasis was placed on facilitating conversation and mentorship opportunities between students. Results & Conclusions: A profoundly positive experience was reported by our medical students that included a decreased anxiety level for the Step 1 examination.

  16. Review of the Oxford Cryocooler

    International Nuclear Information System (INIS)

    Davey, G.

    1990-01-01

    The Oxford Cryocooler incorporates a linear drive compressor operating close to resonance. All dynamic seals are noncontacting clearance seals maintained by mounting the piston and displacer on mechanical suspension systems with infinite fatigue life. The displacer is pneumatically driven but controlled by a miniature linear motor. The cooler is therefore nonwearing and performance can be maintained even in adverse environments by servo control of piston and displacer strokes and relative phase. Split and integral, single- and two-stage coolers have been produced with operating temperatures between 30 K and 200 K, refrigeration powers between 50 mW and several watts and capable of operating in ambient temperatures from -40 C to 70 C. A current project aims to extend the refrigeration power to 500 watts at 80 K. Experimental optimisation techniques have been devised for rapid development of high efficiency coolers

  17. 17 CFR 240.3b-8 - Definitions of “Qualified OTC Market Maker, Qualified Third Market Maker” and “Qualified Block...

    Science.gov (United States)

    2010-04-01

    ... Market Maker, Qualified Third Market Makerâ and âQualified Block Positionerâ. 240.3b-8 Section 240.3b-8... “Qualified Block Positioner”. For the purposes of Regulation U under the Act (12 CFR part 221): (a) The term... inventory turnover in such security. (c) The term Qualified Block Positioner means a dealer who (1) is a...

  18. 36 CFR 908.13 - Rights of Qualified Persons.

    Science.gov (United States)

    2010-07-01

    ... POLICY AND PROCEDURES TO FACILITATE THE RETENTION OF DISPLACED BUSINESSES AND RESIDENTS IN THE... leasing plan which are, in the Corporation's opinion, major. (c) Each Qualified Person on the List, who is... opportunity to occupy Newly Developed Space shall not be limited to the square on which its previous location...

  19. The study on a gas-coupled two-stage stirling-type pulse tube cryocooler

    Science.gov (United States)

    Wu, X. L.; Chen, L. B.; Zhu, X. S.; Pan, C. Z.; Guo, J.; Wang, J. J.; Zhou, Y.

    2017-12-01

    A two-stage gas-coupled Stirling-type pulse tube cryocooler (SPTC) driven by a linear dual-opposed compressor has been designed, manufactured and tested. Both of the stages adopted coaxial structure for compactness. The effect of a cold double-inlet at the second stage on the cooling performance was investigated. The test results show that the cold double-inlet will help to achieve a lower cooling temperature, but it is not conducive to achieving a higher cooling capacity. At present, without the cold double-inlet, the second stage has achieved a no-load temperature of 11.28 K and a cooling capacity of 620 mW/20 K with an input electric power of 450 W. With the cold double-inlet, the no-load temperature is lowered to 9.4 K, but the cooling capacity is reduced to 400 mW/20 K. The structure of the developed cryocooler and the influences of charge pressure, operating frequency and hot end temperature will also be introduced in this paper.

  20. Development of a hermetically sealed brushless DC motor for a J-T cryocooler

    Science.gov (United States)

    Joscelyn, Edwin; Hochler, Irwin; Ferri, Andrew; Rott, Heinz; Soukaris, Ted

    1996-01-01

    This development was sponsored by Ball Aerospace for the Cryogenic On-Orbit LongLife Active Refrigerator (COOLLAR) program. The cryocooler is designed to cool objects to 65 K and operate in space for at least 7 years. The system also imports minimal impact to the spacecraft in terms of vibration and heat. The basic Joule-Thompson cycle involves compressing a working fluid, nitrogen in this case, at near-constant temperature from 17.2 KPa to 6.89 MPa. The nitrogen is then expanded through a Joule-Thompson valve. The pure nitrogen gas must be kept clean; therefore, any contamination from motor organic materials must be eliminated. This requirement drove the design towards sealing of the motor within a titanium housing without sacrificing motor performance. It is estimated that an unsealed motor would have contributed 1.65 g of contaminants, due to the organic insulation and potting materials, over the 7-year life. This paper describes the motor electrical and mechanical design, as well as the sealing difficulties encountered, along with their solutions.

  1. Low-Cost High-Performance Cryocoolers for In-Situ Propellant Production

    Science.gov (United States)

    Martin, J. L.; Corey, J. A.; Peters, T. A.

    1999-01-01

    A key feature of many In-Situ Resource Utilization (ISRU) schemes is the production of rocket fuel and oxidizer from the Martian atmosphere. Many of the fuels under consideration will require cryogenic cooling for efficient long-term storage. Although significant research has been focused on the techniques for producing the fuels from Martian resources, little effort has been expended on the development of cryocoolers to efficiently liquefy these fuels. This paper describes the design of a pulse tube liquefier optimized for liquefying oxygen produced by an In-Situ Propellant Production (ISPP) plant on Mars.

  2. The Ricor K508 cryocooler operational experience on Mars

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Dean L.; Lysek, Mark J.; Morookian, John Michael [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2014-01-29

    The Mars Science Laboratory (Curiosity) landed successfully on Mars on August 5, 2012, eight months after launch. The chosen landing site of Gale Crater, located at 4.5 degrees south latitude, 137.4 degrees east longitude, has provided a much more benign environment than was originally planned for during the critical design and integration phases of the MSL Project when all possible landing sites were still being considered. The expected near-surface atmospheric temperatures at the Gale Crater landing site during Curiosity's primary mission (1 Martian year or 687 Earth days) are from −90°C to 0°C. However, enclosed within Curiosity's thermal control fluid loops the Chemistry and Mineralogy (CheMin) instrument is maintained at approximately +20°C. The CheMin instrument uses X-ray diffraction spectroscopy to make precise measurements of mineral constituents of Mars rocks and soil. The instrument incorporated the commercially available Ricor K508 Stirling cycle cryocooler to cool the CCD detector. After several months of brushing itself off, stretching and testing out its subsystems, Curiosity began the exploration of the Mars surface in October 2012. The CheMin instrument on the Mars Science Laboratory (MSL) received its first soil sample from Curiosity on October 24, and successfully analyzed its first soil sample. After a brief review of the rigorous Ricor K508 cooler qualification tests and life tests based on the original MSL environmental requirements this paper presents final pre-launch instrument integration and testing results, and details the operational data of the CheMin cryocooler, providing a snapshot of the resulting CheMin instrument analytical data.

  3. The Ricor K508 cryocooler operational experience on Mars

    International Nuclear Information System (INIS)

    Johnson, Dean L.; Lysek, Mark J.; Morookian, John Michael

    2014-01-01

    The Mars Science Laboratory (Curiosity) landed successfully on Mars on August 5, 2012, eight months after launch. The chosen landing site of Gale Crater, located at 4.5 degrees south latitude, 137.4 degrees east longitude, has provided a much more benign environment than was originally planned for during the critical design and integration phases of the MSL Project when all possible landing sites were still being considered. The expected near-surface atmospheric temperatures at the Gale Crater landing site during Curiosity's primary mission (1 Martian year or 687 Earth days) are from −90°C to 0°C. However, enclosed within Curiosity's thermal control fluid loops the Chemistry and Mineralogy (CheMin) instrument is maintained at approximately +20°C. The CheMin instrument uses X-ray diffraction spectroscopy to make precise measurements of mineral constituents of Mars rocks and soil. The instrument incorporated the commercially available Ricor K508 Stirling cycle cryocooler to cool the CCD detector. After several months of brushing itself off, stretching and testing out its subsystems, Curiosity began the exploration of the Mars surface in October 2012. The CheMin instrument on the Mars Science Laboratory (MSL) received its first soil sample from Curiosity on October 24, and successfully analyzed its first soil sample. After a brief review of the rigorous Ricor K508 cooler qualification tests and life tests based on the original MSL environmental requirements this paper presents final pre-launch instrument integration and testing results, and details the operational data of the CheMin cryocooler, providing a snapshot of the resulting CheMin instrument analytical data

  4. Validation of accelerated ageing of Thales rotary Stirling cryocoolers for the estimation of MTTF

    Science.gov (United States)

    Seguineau, C.,; Cauquil, J.-M.; Martin, J.-Y.; Benschop, T.

    2016-05-01

    The cooled IR detectors are used in a wide range of applications. Most of the time, the cryocoolers are one of the components dimensioning the lifetime of the system. The current market needs tend to reliability figures higher than 15,000hrs in "standard conditions". Field returns are hardly useable mostly because of the uncertain environmental conditions of use, or the differences in user profiles. A previous paper explains how Thales Cryogenics has developed an approach based on accelerated ageing and statistical analysis [1]. The aim of the current paper is to compare results obtained on accelerated ageing on one side, and on the other side, specific field returns where the conditions of use are well known. The comparison between prediction and effective failure rate is discussed. Moreover, a specific focus is done on how some new applications of cryocoolers (continuous operation at a specific temperature) can increase the MTTF. Some assumptions are also exposed on how the failure modes, effects and criticality analysis evolves for continuous operation at a specific temperature and compared to experimental data.

  5. A cryogenic tensile testing apparatus for micro-samples cooled by miniature pulse tube cryocooler

    International Nuclear Information System (INIS)

    Chen, L B; Liu, S X; Gu, K X; Zhou, Y; Wang, J J

    2015-01-01

    This paper introduces a cryogenic tensile testing apparatus for micro-samples cooled by a miniature pulse tube cryocooler. At present, tensile tests are widely applied to measure the mechanical properties of materials; most of the cryogenic tensile testing apparatus are designed for samples with standard sizes, while for non-standard size samples, especially for microsamples, the tensile testing cannot be conducted. The general approach to cool down the specimens for tensile testing is by using of liquid nitrogen or liquid helium, which is not convenient: it is difficult to keep the temperature of the specimens at an arbitrary set point precisely, besides, in some occasions, liquid nitrogen, especially liquid helium, is not easily available. To overcome these limitations, a cryogenic tensile testing apparatus cooled by a high frequency pulse tube cryocooler has been designed, built and tested. The operating temperatures of the developed tensile testing apparatus cover from 20 K to room temperature with a controlling precision of ±10 mK. The apparatus configurations, the methods of operation and some cooling performance will be described in this paper. (paper)

  6. A 1 T, 0.33 m bore superconducting magnet operating with cryocoolers at 12 K

    NARCIS (Netherlands)

    van der Laan, M.T.G.; van der Laan, M.T.G.; Tax, R.B.; ten Kate, Herman H.J.; van de Klundert, L.J.M.

    1992-01-01

    The application of small cryocoolers to cooling a superconducting magnet at 12 K has important advantages, especially for small and medium-size magnets. Simple construction and a helium-free magnet system were obtained. The demonstration magnet developed is a six-coil system with a volume of 75 L

  7. Design of High Voltage Electrical Breakdown Strength measuring system at 1.8K with a G-M cryocooler

    Science.gov (United States)

    Li, Jian; Huang, Rongjin; Li, Xu; Xu, Dong; Liu, Huiming; Li, Laifeng

    2017-09-01

    Impregnating resins as electrical insulation materials for use in ITER magnets and feeder system are required to be radiation stable, good mechanical performance and high voltage electrical breakdown strength. In present ITER project, the breakdown strength need over 30 kV/mm, for future DEMO reactor, it will be greater than this value. In order to develop good property insulation materials to satisfy the requirements of future fusion reactor, high voltage breakdown strength measurement system at low temperature is necessary. In this paper, we will introduce our work on the design of this system. This measuring system has two parts: one is an electrical supply system which provides the high voltage from a high voltage power between two electrodes; the other is a cooling system which consists of a G-M cryocooler, a superfluid chamber and a heat switch. The two stage G-M cryocooler pre-cool down the system to 4K, the superfluid helium pot is used for a container to depress the helium to superfluid helium which cool down the sample to 1.8K and a mechanical heat switch connect or disconnect the cryocooler and the pot. In order to provide the sufficient time for the test, the cooling system is designed to keep the sample at 1.8K for 300 seconds.

  8. Vibration-free stirling cryocooler for high definition microscopy

    Science.gov (United States)

    Riabzev, S. V.; Veprik, A. M.; Vilenchik, H. S.; Pundak, N.; Castiel, E.

    2009-12-01

    The normal operation of high definition Scanning Electronic and Helium Ion microscope tools often relies on maintaining particular components at cryogenic temperatures. This has traditionally been accomplished by using liquid coolants such as liquid Nitrogen. This inherently limits the useful temperature range to above 77 K, produces various operational hazards and typically involves elevated ownership costs, inconvenient logistics and maintenance. Mechanical coolers, over-performing the above traditional method and capable of delivering required (even below 77 K) cooling to the above cooled components, have been well-known elsewhere for many years, but their typical drawbacks, such as high purchasing cost, cooler size, low reliability and high power consumption have so far prevented their wide-spreading. Additional critical drawback is inevitable degradation of imagery performance originated from the wideband vibration export as typical for the operation of the mechanical cooler incorporating numerous movable components. Recent advances in the development of reliable, compact, reasonably priced and dynamically quiet linear cryogenic coolers gave rise to so-called "dry cooling" technologies aimed at eventually replacing the traditional use of outdated liquid Nitrogen cooling facilities. Although much improved these newer cryogenic coolers still produce relatively high vibration export which makes them incompatible with modern high definition microscopy tools. This has motivated further research activity towards developing a vibration free closed-cycle mechanical cryocooler. The authors have successfully adapted the standard low vibration Stirling cryogenic refrigerator (Ricor model K535-LV) delivering 5 W@40 K heat lift for use in vibration-sensitive high definition microscopy. This has been achieved by using passive mechanical counterbalancing of the main portion of the low frequency vibration export in combination with an active feed-forward multi

  9. Studies of cryocooler based cryosorption pump with activated carbon panels operating at 11K

    International Nuclear Information System (INIS)

    Kasthurirengan, S; Behera, Upendra; Gangradey, Ranjana; Udgata, Swarup; Krishnamoorthy, V

    2012-01-01

    Cryosorption pump is the only solution for pumping helium and hydrogen in fusion reactors. It is chosen because it offers highest pumping speed as well as the only suitable pump for the harsh environments in a tokamak. Towards the development of such cryosorption pumps, the optimal choice of the right activated carbon panels is essential. In order to characterize the performance of the panels with indigenously developed activated carbon, a cryocooler based cryosorption pump with scaled down sizes of panels is experimented. The results are compared with the commercial cryopanel used in a CTI cryosorption (model: Cryotorr 7) pump. The cryopanel is mounted on the cold head of the second stage GM cryocooler which cools the cryopanel down to 11K with first stage reaching about ∼50K. With no heat load, cryopump gives the ultimate vacuum of 2.1E-7 mbar. The pumping speed of different gases such as nitrogen, argon, hydrogen, helium are tested both on indigenous and commercial cryopanel. These studies serve as a bench mark towards the development of better cryopanels to be cooled by liquid helium for use with tokamak.

  10. Simulation of thermal processes in superconducting pancake coils cooled by GM cryocooler

    International Nuclear Information System (INIS)

    Lebioda, M; Rymaszewski, J; Korzeniewska, E

    2014-01-01

    This article presents the thermal model of a small scale superconducting magnetic energy storage system with the closed cycle helium cryocooler. The authors propose the use of contact-cooled coils with maintaining the possibility of the system reconfiguring. The model assumes the use of the second generation superconducting tapes to make the windings in the form of flat discs (pancakes). The paper presents results for a field model of the single pancake coil and the winding system consisting of several coils.

  11. NASA space applications of high-temperature superconductors

    Science.gov (United States)

    Heinen, Vernon O.; Sokoloski, Martin M.; Aron, Paul R.; Bhasin, Kul B.

    1992-01-01

    The application of superconducting technology in space has been limited by the requirement of cooling to near liquid helium temperatures. The only means of attaining these temperatures has been with cryogenic fluids which severely limits mission lifetime. The development of materials with superconducting transition temperatures (T sub c) above 77 K has made superconducting technology more attractive and feasible for employment in aerospace systems. Potential applications of high-temperature superconducting technology in cryocoolers and remote sensing, communications, and power systems are discussed.

  12. Development of New Cryocooler Regenerator Materials-Ductile Intermetallic Compounds

    International Nuclear Information System (INIS)

    Gschneidner, K.A.; Pecharsky, A.O.; Pecharsky, V.K.

    2004-01-01

    The volumetric heat capacities of a number of binary and ternary Er- and Tm-based intermetallic compounds, which exhibited substantial ductilities, were measured from ∼3 to ∼350 K. They have the RM stoichiometry (where R = Er or Tm, and M is a main group or transition metal) and crystallize in the CsCl-type structure. The heat capacities of the Tm-based compounds are in general larger than the corresponding Er-based materials. Many of them have heat capacities which are significantly larger than those of the low temperature ( 2 , Er 3 Ni and ErNi. Utilization of the new materials as regenerators in the various cryocoolers should improve the performance of these refrigeration units for cooling below 15 K

  13. Evaluating a grading change at UCSD school of medicine: pass/fail grading is associated with decreased performance on preclinical exams but unchanged performance on USMLE step 1 scores.

    Science.gov (United States)

    McDuff, Susan G R; McDuff, DeForest; Farace, Jennifer A; Kelly, Carolyn J; Savoia, Maria C; Mandel, Jess

    2014-06-30

    To assess the impact of a change in preclerkship grading system from Honors/Pass/Fail (H/P/F) to Pass/Fail (P/F) on University of California, San Diego (UCSD) medical students' academic performance. Academic performance of students in the classes of 2011 and 2012 (constant-grading classes) were collected and compared with performance of students in the class of 2013 (grading-change class) because the grading policy at UCSD SOM was changed for the class of 2013, from H/P/F during the first year (MS1) to P/F during the second year (MS2). For all students, data consisted of test scores from required preclinical courses from MS1 and MS2 years, and USMLE Step 1 scores. Linear regression analysis controlled for other factors that could be predictive of student performance (i.e., MCAT scores, undergraduate GPA, age, gender, etc.) in order to isolate the effect of the changed grading policy on academic performance. The change in grading policy in the MS2 year only, without any corresponding changes to the medical curriculum, presents a unique natural experiment with which to cleanly evaluate the effect of P/F grading on performance outcomes. After controlling for other factors, the grading policy change to P/F grading in the MS2 year had a negative impact on second-year grades relative to first-year grades (the constant-grading classes performed 1.65% points lower during their MS2 year compared to the MS1 year versus 3.25% points lower for the grading-change class, p < 0.0001), but had no observable impact on USMLE Step 1 scores. A change in grading from H/P/F grading to P/F grading was associated with decreased performance on preclinical examinations but no decrease in performance on the USMLE Step 1 examination. These results are discussed in the broader context of the multitude of factors that should be considered in assessing the merits of various grading systems, and ultimately the authors recommend the continuation of pass-fail grading at UCSD School of Medicine.

  14. Methodology of Accelerated Life-Time Tests For Stirling-Type "Bae-Co"-Made Cryocoolers Against Displacer-Blockage by Cryo-Pollutant Deposits

    National Research Council Canada - National Science Library

    Getmanits, Vladimir

    2000-01-01

    ...: The contractor will investigate techniques for accelerated testing of cryocooler technology. During this phase of the effort the contractor will perform a detailed design of the equipment needed to conduct accelerated testing...

  15. Two-Stage, 20 K Pulse Tube Cryocooler for Space Studies

    Data.gov (United States)

    National Aeronautics and Space Administration — American competitiveness and success are directly correlated with technological innovation and scientific research. NASA is known for its advanced concepts and...

  16. Study of reverse Brayton cryocooler with Helium-Neon mixture for HTS cable

    Science.gov (United States)

    Dhillon, A. K.; Ghosh, P.

    2017-12-01

    As observed in the earlier studies, helium is more efficient than neon as a refrigerant in a reverse Brayton cryocooler (RBC) from the thermodynamic point of view. However, the lower molecular weight of helium leads to higher refrigerant inventory as compared to neon. Thus, helium is suitable to realize the high thermodynamic efficiency of RBC whereas neon is appropriate for the compactness of the RBC. A binary mixture of helium and neon can be used to achieve high thermodynamic efficiency in the compact reverse Brayton cycle (RBC) based cryocooler. In this paper, an attempt has been made to analyze the thermodynamic performance of the RBC with a binary mixture of helium and neon as the working fluid to provide 1 kW cooling load for high temperature superconductor (HTS) power cables working with a temperature range of 50 K to 70 K. The basic RBC is simulated using Aspen HYSYS V8.6®, a commercial process simulator. Sizing of each component based on the optimized process parameters for each refrigerant is performed based on a computer code developed using Engineering Equation Solver (EES-V9.1). The recommendation is provided for the optimum mixture composition of the refrigerant based on the trade-off factors like thermodynamic efficiency such as the exergy efficiency and equipment considerations. The outcome of this study may be useful for recommending a suitable refrigerant for the RBC operating at a temperature level of 50 K to 70 K.

  17. 26 CFR 1.936-10 - Qualified investments.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 10 2010-04-01 2010-04-01 false Qualified investments. 1.936-10 Section 1.936... (CONTINUED) INCOME TAXES Possessions of the United States § 1.936-10 Qualified investments. (a) In general. [Reserved] (b) Qualified investments in Puerto Rico. [Reserved] (c) Qualified investment in certain...

  18. Space-Qualifiable Digital Radar Transceiver, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Historically, radar systems have tended to be either large, complex, power-hungry, purpose-built systems, or extremely simple systems of limited capability. More...

  19. Space-qualifiable Digital Radar Transceiver, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Radar technology offers a very flexible, powerful tool for applications such as object detection, tracking, and characterization, as well as remote sensing, imaging,...

  20. An Improved X-Band Maser System for Deep Space Network Applications

    Science.gov (United States)

    Britcliffe, M.; Hanson, T.; Fernandez, J.

    2000-01-01

    An 8450-MHz (X-band) maser system utilizing a commercial Gifford--McMahon (GM) closed-cycle cryocooler (CCR) was designed, fabricated, and demonstrated. The CCR system was used to cool a maser operating at 8450 MHz. The prototype GM CCR system meets or exceeds all Deep Space Network requirements for maser performance. The two-stage GM CCR operates at 4.2 K; for comparison, the DSN's current three-stage cryocooler, which uses a Joule--Thompson cooling stage in addition to GM cooling, operates at 4.5 K. The new CCR withstands heat loads of 1.5 W at 4.2 K as compared to 1 W at 4.5 K for the existing DSN cryocooler used for cooling masers. The measured noise temperature, T_e, of the maser used for these tests is defined at the ambient connection to the antenna feed system. The T_e measured 5.0 K at a CCR temperature of 4.5 K, about 1.5 K higher than the noise temperature of a typical DSN Block II-A X-band traveling-wave maser (TWM). Reducing the temperature of the CCR significantly lowers the maser noise temperature and increases maser gain and bandwidth. The new GM CCR gives future maser systems significant operational advantages, including reduced maintenance time and logistics requirements. The results of a demonstration of this new system are presented. Advantages of using a GM-cooled maser and the effects of the reduced CCR temperature on maser performance are discussed.

  1. Numerical simulation of tubes-in-tube heat exchanger in a mixed refrigerant Joule-Thomson cryocooler

    Science.gov (United States)

    Damle, R. M.; Ardhapurkar, P. M.; Atrey, M. D.

    2017-02-01

    Mixed refrigerant Joule-Thomson (MRJT) cryocoolers can produce cryogenic temperatures with high efficiency and low operating pressures. As compared to the high system pressures of around 150-200 bar with nitrogen, the operational pressures with non-azeotropic mixtures (e.g., nitrogen-hydrocarbons) come down to 10-25 bar. With mixtures, the heat transfer in the recuperative heat exchanger takes place in the two-phase region. The simultaneous boiling and condensation of the cold and hot gas streams lead to higher heat transfer coefficients as compared to single phase heat exchange. The two-phase heat transfer in the recuperative heat exchanger drastically affects the performance of a MRJT cryocooler. In this work, a previously reported numerical model for a simple tube-in-tube heat exchanger is extended to a multi tubes-in-tube heat exchanger with a transient formulation. Additionally, the J-T expansion process is also considered to simulate the cooling process of the heat exchanger from ambient temperature conditions. A tubes-in-tube heat exchanger offers more heat transfer area per unit volume resulting in a compact design. Also, the division of flow in multiple tubes reduces the pressure drop in the heat exchanger. Simulations with different mixtures of nitrogen-hydrocarbons are carried out and the numerical results are compared with the experimental data.

  2. 7 CFR 4290.110 - Qualified management.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Qualified management. 4290.110 Section 4290.110... Qualifications for the RBIC Program Organizing A Rbic § 4290.110 Qualified management. An Applicant must show, to the satisfaction of the Secretary, that its current or proposed management team is qualified and has...

  3. Thermal Analysis of Cryocooler-Cooled Bi2223 Pulsed Coil

    International Nuclear Information System (INIS)

    Miyazaki, H; Chigusa, S; Tanaka, I; Iwakuma, M; Funaki, K; Hayashi, H; Tomioka, A

    2006-01-01

    We fabricated a cryocooler-cooled Bi2223 superconducting pulsed coil and experimentally studied thermal runaway in dc or ac operation. We carried out numerical simulation of thermal properties of the coil in order to explain thermal runaway of the coil. Firstly, we analyzed the total heat generation of flux-flow loss and ac loss inside the winding from the experimental results of the external field losses and the E-J characteristics for the Bi2223 strands. Secondly, we numerically simulated the thermal properties by using 2- dimensional heat conduction equation with axial symmetry. The numerical simulation shows the relation between the initiation of thermal runaway and the temperature distribution with highly concentrated heat source in the winding. We have a semi-quantitative agreement between the numerical results and the experimental ones for the condition of the thermal runaway

  4. Operating characteristics of a three-stage Stirling pulse tube cryocooler operating around 5 K

    Science.gov (United States)

    Qiu, L. M.; Cao, Q.; Zhi, X. Q.; Han, L.; Gan, Z. H.; Yu, Y. B.; Liu, Y.; Zhang, X. J.; Pfotenhauer, J. M.

    2012-07-01

    A Stirling pulse tube cryocooler (SPTC) operating at the liquid-helium temperatures represents an excellent prospect for satisfying the requirements of space applications because of its compactness, high efficiency and reliability. However, the working mechanism of a 4 K SPTC is more complicated than that of the Gifford McMahon (GM) PTC that operates at the relatively low frequency of 1-2 Hz, and has not yet been well understood. In this study, the primary operating parameters, including frequency, charge pressure, input power and precooling temperature, are systematically investigated in a home-developed separate three-stage SPTC. The investigation demonstrates that the frequency and precooling temperature are closely coupled via phase shift. In order to improve the cooling capacity it is important to lower the frequency and the precooling temperature simultaneously. In contrast to the behavior predicted by previous studies, the pressure dependence of the gas properties results in an optimized pressure that decreases significantly as the temperature is lowered. The third stage reaches a lowest temperature of 4.97 K at 29.9 Hz and 0.91 MPa. A cooling power of 25 mW is measured at 6.0 K. The precooling temperature is 23.7 K and the input power is 100 W.

  5. Space for Interaction

    DEFF Research Database (Denmark)

    Jørgensen, Mariane Ellen; Folmer, Mette Blicher; Mullins, Michael

    SPACE FOR INTERACTION QUALIFYING GROUP TREATMENT FOR PATIENTS WITH CHRONIC PAIN THROUGH OPTIMIZATION(?) OF SPACE. A RANDOMIZED PILOT STUDY. In a Ph-D. Mariane Ellen Jørgensen / Nurse + psykoterapist / maej@rn.dk / Pain Center / Aalborg University Hospital / Denmark / Mette Blicher Folmer / Archit...

  6. Observation of quantized vortices by cryocooler-based scanning Hall probe microscope

    Energy Technology Data Exchange (ETDEWEB)

    Tokunaga, Y.; Konishi, Y.; Tokunaga, M.; Tamegai, T

    2004-10-01

    We have developed a scanning Hall probe microscope (SHPM) system utilizing closed-cycle cryocooler. The Hall probe used in this system is fabricated from a GaAs/GaAlAs two-dimensional electron gas. A stepping-motor-driven XYZ translator is used with a resolution better than 0.1 {mu}m and maximum scan range of 20 x 20 mm{sup 2}. The spatial resolution of the system is about 5 {mu}m and magnetic resolution is about 100 mG. By using this system, we have successfully resolved the quantized vortices on the cleaved surface of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+y} single crystal.

  7. Highly qualified in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Renata Čuhlová

    2017-05-01

    Full Text Available The paper aims to analyse the current situation of the highly qualified in the Czech Republic applying the ISCO qualification. Previous studies suggest that educational attainment has an important impact on labour market performance and national competitiveness. Data analyses approved that highly qualified workforce positively influences economic situation of the EU–15 Member States they work in. However, this hypothesis was disapproved for the EU–10+3 Member States joining the EU after 2004. The difference can be explained by the various stage in convergence process since some New Member States are still in transformation period. We positively appraise the significant growth of fraction of the highly qualified in the Czech Republic since 2004, especially in the major group Professionals involving the most qualified workforce. The same trend happened also for the highly qualified foreigners in the Czech Republic, however their attracting still remains a challenge.

  8. Automated Cryocooler Monitor and Control System

    Science.gov (United States)

    Britcliffe, Michael J.; Hanscon, Theodore R.; Fowler, Larry E.

    2011-01-01

    A system was designed to automate cryogenically cooled low-noise amplifier systems used in the NASA Deep Space Network. It automates the entire operation of the system including cool-down, warm-up, and performance monitoring. The system is based on a single-board computer with custom software and hardware to monitor and control the cryogenic operation of the system. The system provides local display and control, and can be operated remotely via a Web interface. The system controller is based on a commercial single-board computer with onboard data acquisition capability. The commercial hardware includes a microprocessor, an LCD (liquid crystal display), seven LED (light emitting diode) displays, a seven-key keypad, an Ethernet interface, 40 digital I/O (input/output) ports, 11 A/D (analog to digital) inputs, four D/A (digital to analog) outputs, and an external relay board to control the high-current devices. The temperature sensors used are commercial silicon diode devices that provide a non-linear voltage output proportional to temperature. The devices are excited with a 10-microamp bias current. The system is capable of monitoring and displaying three temperatures. The vacuum sensors are commercial thermistor devices. The output of the sensors is a non-linear voltage proportional to vacuum pressure in the 1-Torr to 1-millitorr range. Two sensors are used. One measures the vacuum pressure in the cryocooler and the other the pressure at the input to the vacuum pump. The helium pressure sensor is a commercial device that provides a linear voltage output from 1 to 5 volts, corresponding to a gas pressure from 0 to 3.5 MPa (approx. = 500 psig). Control of the vacuum process is accomplished with a commercial electrically operated solenoid valve. A commercial motor starter is used to control the input power of the compressor. The warm-up heaters are commercial power resistors sized to provide the appropriate power for the thermal mass of the particular system, and

  9. 26 CFR 1.30-1 - Definition of qualified electric vehicle and recapture of credit for qualified electric vehicle.

    Science.gov (United States)

    2010-04-01

    ... qualified electric vehicle. A qualified electric vehicle is a motor vehicle that meets the requirements of section 30(c). Accordingly, a qualified electric vehicle does not include any motor vehicle that has ever been used (for either personal or business use) as a non-electric vehicle. (b) Recapture of credit for...

  10. Use of advanced commercial ICs (COTS) for space application

    International Nuclear Information System (INIS)

    Strobel, D.J.; Czajkowski, D.R.; Layton, P.; Shanken, S.

    1999-01-01

    A product line of space-qualified radiation-tolerant ICs based on a high-volume commercial-off-the-shelf (COTS) silicon has been developed. The basic results from over 300 lots of COTS silicon, assembled and screened to Class B and Class S requirements will be presented. Intelligent use of commercial ICs engineered to improve radiation performance, is effective in introducing advanced technology to new satellite systems. Space Electronics has introduced over 125 space-qualified microelectronics standard products, that are used on over 90 space projects. (authors)

  11. 11 CFR 9002.11 - Qualified campaign expense.

    Science.gov (United States)

    2010-01-01

    ... 11 Federal Elections 1 2010-01-01 2010-01-01 false Qualified campaign expense. 9002.11 Section 9002.11 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: GENERAL ELECTION FINANCING DEFINITIONS § 9002.11 Qualified campaign expense. (a) Qualified campaign expense means...

  12. 11 CFR 9032.9 - Qualified campaign expense.

    Science.gov (United States)

    2010-01-01

    ... 11 Federal Elections 1 2010-01-01 2010-01-01 false Qualified campaign expense. 9032.9 Section 9032.9 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: PRESIDENTIAL PRIMARY MATCHING FUND DEFINITIONS § 9032.9 Qualified campaign expense. (a) Qualified campaign expense...

  13. The Fabrication of Qualified Citizens

    DEFF Research Database (Denmark)

    Andrade-Molina, Melissa

    2017-01-01

    a rhizomatic analytical move, a historization of the present is deployed to map the fabrication of the desired qualified citizen in Chile. The analysis evidences the (re)production of dominant narratives about the “qualified citizen” are and have been entangled with the functioning of school geometry...

  14. M2 qualify laser beam propagation

    International Nuclear Information System (INIS)

    Abdelhalim, Bencheikh; Mohamed, Bouafia

    2010-01-01

    One of the most important properties of a laser resonator is the highly collimated or spatially coherent nature of the laser output beam. Laser beam diameter and quality factor M 2 are significant parameters in a wide range of laser applications. This is because the spatial beam quality determines how closely the beam can be focused or how well the beam propagates over long distances without significant dispersion. In the present paper we have used three different methods to qualify the spatial structure of a laser beam propagating in free space, the results are obtained and discussed, and we have found that the Wigner distribution function is a powerful tool which allows a global characterization of any kind of beam

  15. Effect of Low Temperature on a 4 W/60 K Pulse-Tube Cryocooler for Cooling HgCdTe Detector

    Science.gov (United States)

    Zhang, Ankuo; Liu, Shaoshuai; Wu, Yinong

    2018-04-01

    Temperature is an extremely important parameter for the material of the space-borne infrared detector. To cool an HgCdTe-infrared detector, a Stirling-type pulse-tube cryocooler (PTC) has been developed based on a great deal of numerical simulations, which are performed to investigate the thermodynamic behaviors of the PTC. The effects of different low temperatures are presented to analyze different energy flows, losses, phase shifts, and impedance matching of the PTC at a temperature range of 40-120 K, where woven wire screens are used. Finally, a high-efficiency coaxial PTC has been designed, built, and tested, operating around 60 K after a number of theoretical and experimental studies. The PTC can offer a no-load refrigeration temperature of 40 K with an input electric power of 150 W, and a cooling power of 4 W at 60 K is obtained with Carnot efficiency of 12%. In addition, a comparative study of simulation and experiment has been carried out, and some studies on reject temperatures have been presented for a thorough understanding of the PTC system.

  16. 21 CFR 516.141 - Qualified expert panels.

    Science.gov (United States)

    2010-04-01

    ... choose members for the qualified expert panel in accordance with selection criteria listed in paragraph... whether the proposed qualified expert panel meets the selection criteria prior to the panel beginning its... Committee Act, as amended, 5 U.S.C. App. (b) Criteria for the selection of a qualified expert panel. (1) A...

  17. Preliminary test Results for a 25K Sorption Cryocooler Designed for the UCSB Long Duration Balloon Cosmic Microwave Background Radiation Experiment

    Science.gov (United States)

    Wade, L. A.; Levy, A. R.

    1996-01-01

    A continuous operation, vibration-free, long-life 25K sorption cryocooler has been built and is now in final integration and performance testing. This cooler wil be flown on the University of California at Santa Barbara (UCSB) Long Duration Balloon (LDB) Cosmic Microwave Background Radiation Experiment.

  18. Numerical investigation of transient behaviour of the recuperative heat exchanger in a MR J-T cryocooler using different heat transfer correlations

    Science.gov (United States)

    Damle, R. M.; Ardhapurkar, P. M.; Atrey, M. D.

    2016-12-01

    In J-T cryocoolers operating with mixed refrigerants (nitrogen-hydrocarbons), the recuperative heat exchange takes place under two-phase conditions. Simultaneous boiling of the low pressure stream and condensation of the high pressure stream results in higher heat transfer coefficients. The mixture composition, operating conditions and the heat exchanger design are crucial for obtaining the required cryogenic temperature. In this work, a one-dimensional transient algorithm is developed for the simulation of the two-phase heat transfer in the recuperative heat exchanger of a mixed refrigerant J-T cryocooler. Modified correlation is used for flow boiling of the high pressure fluid while different condensation correlations are employed with and without the correction for the low pressure fluid. Simulations are carried out for different mixture compositions and numerical predictions are compared with the experimental data. The overall heat transfer is predicted reasonably well and the qualitative trends of the temperature profiles are also captured by the developed numerical model.

  19. 33 CFR 155.1026 - Qualified individual and alternate qualified individual.

    Science.gov (United States)

    2010-07-01

    ... familiar with the implementation of the vessel response plan; and (4) Be trained in the responsibilities of... vessel may designate an organization to fulfill the role of the qualified individual and alternate...

  20. Supply Inventory Management: Evaluation of the Defense Supply Center Columbus Qualified Products List and Qualified Manufacturers List Program

    National Research Council Canada - National Science Library

    2002-01-01

    ... was transitioned from the Military Departments. The Defense Supply Center Columbus currently has management responsibility for over 300 Qualified Products Lists and 4 Qualified Manufacturers Lists...

  1. Reflections on the newly qualified social worker's journey : From university training to qualified practice

    OpenAIRE

    Walker, Clare

    2014-01-01

    This qualitative research study explores the experience of graduating social workers making the transition from university training into work as qualified social work practitioners. Most studies in this area look at the practice readiness of the newly qualified professional. This study looks at the participants’ experience in the work place. How do participants experience this journey of transition? What skills, particularly reflective practice and supervision, learned in training, are import...

  2. 33 CFR 154.1026 - Qualified individual and alternate qualified individual.

    Science.gov (United States)

    2010-07-01

    ... alternate must: (1) Be located in the United States; (2) Speak fluent English; (3) Be familiar with the... facility may designate an organization to fulfill the role of the qualified individual and the alternate...

  3. Microcrystallography, high-pressure cryocooling and BioSAXS at MacCHESS

    Energy Technology Data Exchange (ETDEWEB)

    Englich, Ulrich, E-mail: ue22@cornell.edu; Kriksunov, Irina A. [MacCHESS (Macromolecular Diffraction Facility at CHESS), Cornell University, Ithaca, NY 14853 (United States); Cerione, Richard A. [MacCHESS (Macromolecular Diffraction Facility at CHESS), Cornell University, Ithaca, NY 14853 (United States); Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853 (United States); Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853 (United States); Cook, Michael J.; Gillilan, Richard [MacCHESS (Macromolecular Diffraction Facility at CHESS), Cornell University, Ithaca, NY 14853 (United States); Gruner, Sol M. [Field of Biophysics, Cornell University, Ithaca, NY 14853 (United States); Physics Department, Cornell University, Ithaca, NY 14853 (United States); Huang, Qingqui; Kim, Chae Un; Miller, William; Nielsen, Soren; Schuller, David; Smith, Scott; Szebenyi, Doletha M. E. [MacCHESS (Macromolecular Diffraction Facility at CHESS), Cornell University, Ithaca, NY 14853 (United States)

    2011-01-01

    Three research initiatives pursued by the Macromolecular Diffraction Facility at the Cornell High Energy Synchrotron Source (MacCHESS) are presented. The Macromolecular Diffraction Facility at the Cornell High Energy Synchrotron Source (MacCHESS) is a national research resource supported by the National Center for Research Resources of the US National Institutes of Health. MacCHESS is pursuing several research initiatives designed to benefit both CHESS users and the wider structural biology community. Three initiatives are presented in further detail: microcrystallography, which aims to improve the collection of diffraction data from crystals a few micrometers across, or small well diffracting regions of inhomogeneous crystals, so as to obtain high-resolution structures; pressure cryocooling, which can stabilize transient structures and reduce lattice damage during the cooling process; and BioSAXS (small-angle X-ray scattering on biological solutions), which can extract molecular shape and other structural information from macromolecules in solution.

  4. Hydrodynamic parameters of micro porous media for steady and oscillatory flow: Application to cryocooler regenerators

    Science.gov (United States)

    Cha, Jeesung Jeff

    Pulse Tube Cryocoolers (PTC) are a class of rugged and high-endurance refrigeration systems that operate without a moving part at their low temperature ends, and are capable of easily reaching 120°K. These devices can also be configured in multiple stages to reach temperatures below 10 °K. PTCs are particularly suitable for applications in space, missile guiding systems, cryosurgery, medicine preservation, superconducting electronics, magnetic resonance imaging, weather observation, and liquefaction of nitrogen. Although various designs of PTCs have been in use for a few decades, they represent a dynamic and developmental field. PTCs ruggedness comes at the price of relatively low efficiency, however, and thus far they have been primarily used in high-end applications. They have the potential of extensive use in consumer products, however, should sufficiently higher efficiencies be achieved. Intense research competition is underway worldwide, and newer designs are continuously introduced. Some of the fundamental processes that are responsible for their performance are at best not fully understood, however, and consequently systematic modeling of PTC systems is difficult. Among the challenges facing the PTC research community, besides improvement in terms of system efficiency, is the possible miniaturization (total fluid volume of few cubic centimeters (cc)) of these systems. The operating characteristics of a PTC are significantly different from the conventional refrigeration cycles. A PTC implements the theory of oscillatory compression and expansion of the gas within a closed volume to achieve desired refrigeration. Regenerators and pulse tubes are often viewed as the two most complex and essential components in cryocoolers. An important deficiency with respect to the state of art models dealing with PTCs is the essentially total lack of understanding about the directional hydrodynamic and thermal transport parameters associated with periodic flow in

  5. All-Ceramic Body Flap Qualified for Space Flight on X38

    Science.gov (United States)

    Pfeiffer, H.; Peetz, K.

    2002-01-01

    electromechanical actuator having a third hot bearing. The hinge line gap at the front part of the body flap is closed by a dynamic sealing system to minimize the flow of very hot gases to the leeward side. The paper in hand reports on design, manufacturing and assembly, together with the qualification of the body flaps and their components while the qualification test of the complete flap assembly is brought into focus. Flight readiness was approved by a series of qualification tests representing the full load spectrum of the X- 38 mission. It covered acceptance -, ascend vibration -, thermal transient -, static pressure - and finally descend vibration tests. Special facilities have been developed and manufactured for ground qualification of the flap assembly and the critical subcomponents. The manufacture and qualification of the X-38 body flaps represent a true milestone in the application of CMC. The stringent requirements and constraints, resulting from the assembly of many complex subcompo- nents and vehicle interfaces, require high material quality and precise manufacturing tolerances. Each qualification - and flight hardware element is therefore subjected to rigorous specifications, following detailed manufacturing process procedures with extensive quality control steps, as well as comprehensive documentation of design, analysis, manufacturing, assembly, interface control and vehicle integration. This challenge has been accepted and the objective to utilize MAN Technology's C/SiC as hot, load-carrying structures has reached a promising threshold. Material maturity as well as manufacturing competence is at a level where design and fabrication of CMC components for a operational re-entry vehicle can be proposed. The implementation of lightweight, durable ceramic hot structures is an innovative step forward in new spacecraft design. 1Name of Conference to which abstract is53 rd IAC 2Submission StatusFirst Submission 3TitleAll-Ceramic Body Flap Qualified for Space 4Authors

  6. The Unification of Space Qualified Integrated Circuits by Example of International Space Project GAMMA-400

    Science.gov (United States)

    Bobkov, S. G.; Serdin, O. V.; Arkhangelskiy, A. I.; Arkhangelskaja, I. V.; Suchkov, S. I.; Topchiev, N. P.

    The problem of electronic component unification at the different levels (circuits, interfaces, hardware and software) used in space industry is considered. The task of computer systems for space purposes developing is discussed by example of scientific data acquisition system for space project GAMMA-400. The basic characteristics of high reliable and fault tolerant chips developed by SRISA RAS for space applicable computational systems are given. To reduce power consumption and enhance data reliability, embedded system interconnect made hierarchical: upper level is Serial RapidIO 1x or 4x with rate transfer 1.25 Gbaud; next level - SpaceWire with rate transfer up to 400 Mbaud and lower level - MIL-STD-1553B and RS232/RS485. The Ethernet 10/100 is technology interface and provided connection with the previously released modules too. Systems interconnection allows creating different redundancy systems. Designers can develop heterogeneous systems that employ the peer-to-peer networking performance of Serial RapidIO using multiprocessor clusters interconnected by SpaceWire.

  7. Space Qualified, Radiation Hardened, Dense Monolithic Flash Memory, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Radiation hardened nonvolatile memories for space is still primarily confined to EEPROM. There is high density effective or cost effective NVM solution available to...

  8. 11 CFR 9004.4 - Use of payments; examples of qualified campaign expenses and non-qualified campaign expenses.

    Science.gov (United States)

    2010-01-01

    ... 11 Federal Elections 1 2010-01-01 2010-01-01 false Use of payments; examples of qualified campaign expenses and non-qualified campaign expenses. 9004.4 Section 9004.4 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: GENERAL ELECTION FINANCING ENTITLEMENT OF ELIGIBLE CANDIDATES...

  9. Nominal Group as Qualifier to "Someone"

    Science.gov (United States)

    Sujatna, Eva Tuckyta Sari; Wahyuni, Sri

    2017-01-01

    The paper titled "Nominal Group as Qualifier to 'Someone'" investigated types of qualifiers which are embedded to the head "someone" in a nominal group. This research was conducted in the light of Systemic Functional Linguistics analysis. The data was analyzed, classified then described using descriptive qualitative method.…

  10. How has my learning enabled me to create and share an animated video to assist newly qualified teachers in the creation of a safe critical space for their students?

    OpenAIRE

    Gallagher, Emma

    2011-01-01

    This paper presents my emergent living theory as it developed while I attempted to address my concern “How has my learning enabled me to create and share an animated video to assist Newly Qualified Teachers in the creation of a safe critical space for their students?” I explore how my learning on the Masters in Education and Training Management (e-learning) has affected me both personally and professionally and how my learning has impacted the learning of others. In particular, I look at t...

  11. Modelling of a stirling cryocooler regenerator under steady and steady - periodic flow conditions using a correlation based method

    Science.gov (United States)

    Kishor Kumar, V. V.; Kuzhiveli, B. T.

    2017-12-01

    The performance of a Stirling cryocooler depends on the thermal and hydrodynamic properties of the regenerator in the system. CFD modelling is the best technique to design and predict the performance of a Stirling cooler. The accuracy of the simulation results depend on the hydrodynamic and thermal transport parameters used as the closure relations for the volume averaged governing equations. A methodology has been developed to quantify the viscous and inertial resistance terms required for modelling the regenerator as a porous medium in Fluent. Using these terms, the steady and steady - periodic flow of helium through regenerator was modelled and simulated. Comparison of the predicted and experimental pressure drop reveals the good predictive power of the correlation based method. For oscillatory flow, the simulation could predict the exit pressure amplitude and the phase difference accurately. Therefore the method was extended to obtain the Darcy permeability and Forchheimer’s inertial coefficient of other wire mesh matrices applicable to Stirling coolers. Simulation of regenerator using these parameters will help to better understand the thermal and hydrodynamic interactions between working fluid and the regenerator material, and pave the way to contrive high performance, ultra-compact free displacers used in miniature Stirling cryocoolers in the future.

  12. Comparative simulation of Stirling and Sibling cycle cryocoolers with two codes

    International Nuclear Information System (INIS)

    Mitchell, M.P.; Wilson, K.J.; Bauwens, L.

    1989-01-01

    The authors present a comparative analysis of Stirling and Sibling Cycle cryocoolers conducted with two different computer simulation codes. One code (CRYOWEISS) performs an initial analysis on the assumption of isothermal conditions in the machines and adjusts that result with decoupled loss calculations. The other code (MS*2) models fluid flows and heat transfers more realistically but ignores significant loss mechanisms, including flow friction and heat conduction through the metal of the machines. Surprisingly, MS*2 is less optimistic about performance of all machines even though it ignores losses that are modelled by CRYOWEISS. Comparison between constant-bore Stirling and Sibling machines shows that their performance is generally comparable over a range of temperatures, pressures and operating speeds. No machine was consistently superior or inferior according to both codes over the whole range of conditions studied

  13. 30 CFR 75.155 - Qualified hoisting engineer; qualifications.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Qualified hoisting engineer; qualifications. 75... Persons § 75.155 Qualified hoisting engineer; qualifications. (a)(1) A person is a qualified hoisting engineer within the provisions of subpart O of this part, for the purpose of operating a steam-driven hoist...

  14. Space Qualified, Radiation Hardened, Dense Monolithic Flash Memory, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Space Micro proposes to build a radiation hardened by design (RHBD) flash memory, using a modified version of our RH-eDRAM Memory Controller to solve all the single...

  15. Qualified Census Tracts

    Data.gov (United States)

    Department of Housing and Urban Development — A Qualified Census Tract (QCT) is any census tract (or equivalent geographic area defined by the Census Bureau) in which at least 50% of households have an income...

  16. 26 CFR 1.132-9 - Qualified transportation fringes.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Qualified transportation fringes. 1.132-9... Qualified transportation fringes. (a) Table of contents. This section contains a list of the questions and answers in § 1.132-9. (1) General rules. Q-1. What is a qualified transportation fringe? Q-2. What is...

  17. Cryogenic system with GM cryocooler for krypton, xenon separation from hydrogen-helium purge gas

    Energy Technology Data Exchange (ETDEWEB)

    Chu, X. X.; Zhang, D. X.; Qian, Y.; Liu, W. [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800 (China); Zhang, M. M.; Xu, D. [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190 (China)

    2014-01-29

    In the thorium molten salt reactor (TMSR), fission products such as krypton, xenon and tritium will be produced continuously in the process of nuclear fission reaction. A cryogenic system with a two stage GM cryocooler was designed to separate Kr, Xe, and H{sub 2} from helium purge gas. The temperatures of two stage heat exchanger condensation tanks were maintained at about 38 K and 4.5 K, respectively. The main fluid parameters of heat transfer were confirmed, and the structural heat exchanger equipment and cold box were designed. Designed concentrations after cryogenic separation of Kr, Xe and H{sub 2} in helium recycle gas are less than 1 ppb.

  18. High efficiency, low frequency linear compressor proposed for Gifford-McMahon and pulse tube cryocoolers

    Energy Technology Data Exchange (ETDEWEB)

    Höhne, Jens [Pressure Wave Systems GmbH, Häberlstr. 8, 80337 Munich (Germany)

    2014-01-29

    In order to reduce the amount of greenhouse gas emissions, which are most likely the cause of substantial global warming, a reduction of overall energy consumption is crucial. Low frequency Gifford-McMahon and pulse tube cryocoolers are usually powered by a scroll compressor together with a rotary valve. It has been theoretically shown that the efficiency losses within the rotary valve can be close to 50%{sup 1}. In order to eliminate these losses we propose to use a low frequency linear compressor, which directly generates the pressure wave without using a rotary valve. First results of this development will be presented.

  19. Qualified Empathy - Project Report 2015-16

    DEFF Research Database (Denmark)

    Austring, Bennye Düranc; Sørensen, Merete Cornet

    2016-01-01

    UCSJ-delen af den afsluttende rapport fra Nordplus-projektet "Qualified Empathy", der blev gennemført sammen med Metropolia, Helsinki, og NTNU, Trondheim, i 2015 og 15.......UCSJ-delen af den afsluttende rapport fra Nordplus-projektet "Qualified Empathy", der blev gennemført sammen med Metropolia, Helsinki, og NTNU, Trondheim, i 2015 og 15....

  20. 26 CFR 1.42-6 - Buildings qualifying for carryover allocations.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 1 2010-04-01 2010-04-01 true Buildings qualifying for carryover allocations. 1... INCOME TAXES Credits Against Tax § 1.42-6 Buildings qualifying for carryover allocations. (a) Carryover... carryover allocation may only be made with respect to a qualified building. A qualified building is any...

  1. A Flexible VHDL Floating Point Module for Control Algorithm Implementation in Space Applications

    Science.gov (United States)

    Padierna, A.; Nicoleau, C.; Sanchez, J.; Hidalgo, I.; Elvira, S.

    2012-08-01

    The implementation of control loops for space applications is an area with great potential. However, the characteristics of this kind of systems, such as its wide dynamic range of numeric values, make inadequate the use of fixed-point algorithms.However, because the generic chips available for the treatment of floating point data are, in general, not qualified to operate in space environments and the possibility of using an IP module in a FPGA/ASIC qualified for space is not viable due to the low amount of logic cells available for these type of devices, it is necessary to find a viable alternative.For these reasons, in this paper a VHDL Floating Point Module is presented. This proposal allows the design and execution of floating point algorithms with acceptable occupancy to be implemented in FPGAs/ASICs qualified for space environments.

  2. 26 CFR 1.43-4 - Qualified enhanced oil recovery costs.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 1 2010-04-01 2010-04-01 true Qualified enhanced oil recovery costs. 1.43-4... TAXES Credits Against Tax § 1.43-4 Qualified enhanced oil recovery costs. (a) Qualifying costs—(1) In... “qualified enhanced oil recovery costs” if the amounts are paid or incurred with respect to an asset which is...

  3. Three-stage linear, split-Stirling cryocooler for 1 to 2K magnetic cold stage

    International Nuclear Information System (INIS)

    Longsworth, R.C.

    1993-08-01

    A long-life, linear, high efficiency 8K split Stirling cycle cryocooler was designed, built, and tested. The refrigerator is designed for cooling a 50 mW, 1.5K magnetic cold stage. Dual opposed piston compressors are driven by moving-coil linear motors. The three stage expander, although not completed, is also driven by a linear motor and is designed to produce 1 SW at 60K, 4W at 16K, and 1.2W at 8K. The cold regenerator employs a parallel gap construction for high efficiency. The key technology areas addressed include warm and cold flexible suspension bearings and a new cold regenerator geometry for high efficiency at 8K

  4. Cryocooled wideband digital channelizing radio-frequency receiver based on low-pass ADC

    International Nuclear Information System (INIS)

    Vernik, Igor V; Kirichenko, Dmitri E; Dotsenko, Vladimir V; Miller, Robert; Webber, Robert J; Shevchenko, Pavel; Talalaevskii, Andrei; Gupta, Deepnarayan; Mukhanov, Oleg A

    2007-01-01

    We have demonstrated a digital receiver performing direct digitization of radio-frequency signals over a wide frequency range from kilohertz to gigahertz. The complete system, consisting of a cryopackaged superconductor all-digital receiver (ADR) chip followed by room-temperature interface electronics and a field programmable gate array (FPGA) based post-processing module, has been developed. The ADR chip comprises a low-pass analog-to-digital converter (ADC) delta modulator with phase modulation-demodulation architecture together with digital in-phase and quadrature mixer and a pair of digital decimation filters. The chip is fabricated using a 4.5 kA cm -2 process and is cryopackaged using a commercial-off-the-shelf cryocooler. Experimental results in HF, VHF, UHF and L bands and their analysis, proving consistent operation of the cryopackaged ADR chip up to 24.32 GHz clock frequency, are presented and discussed

  5. 12 CFR 621.4 - Audit by qualified public accountant.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Audit by qualified public accountant. 621.4... REQUIREMENTS General Rules § 621.4 Audit by qualified public accountant. (a) Each institution shall, at least annually, have its financial statements audited by a qualified public accountant in accordance with...

  6. 26 CFR 1.7704-3 - Qualifying income.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Qualifying income. 1.7704-3 Section 1.7704-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES General Actuarial Valuations § 1.7704-3 Qualifying income. (a) Certain investment income—(1...

  7. High efficiency 40 K single-stage Stirling-type pulse tube cryocooler

    Science.gov (United States)

    Wu, X. L.; Chen, L. B.; Pan, C. Z.; Cui, C.; Wang, J. J.; Zhou, Y.

    2017-12-01

    A high efficiency single-stage Stirling-type coaxial pulse tube cryocooler (SPTC) operating at around 40 K has been designed, built and tested. The double-inlet and the inertance tubes together with the gas reservoir were adopted as the phase shifters. Under the conditions of 2.5 MPa charging pressure and 30 Hz operating frequency, the prototype has achieved a no-load temperature of 23.8 K with 330 W of electric input power at a rejection temperature of 279 K. When the input power increases to 400 W, it can achieve a cooling capacity of 4.7 W/40 K while rejecting heat at 279 K yielding an efficiency of 7.02% relative to Carnot. It achieves a cooling capacity of 5 W/40 K with an input power of 450 W. It takes 10 minutes for the SPTC to cool to its no-load temperature of 40 K from 295 K.

  8. Accident data study of concrete construction companies' similarities and differences between qualified and non-qualified workers in Spain.

    Science.gov (United States)

    López-Arquillos, Antonio; Rubio-Romero, Juan Carlos; Gibb, Alistair

    2015-01-01

    The aim of this paper is to discuss findings from an analysis of accidents in concrete construction companies in Spain and to compare the accident rates of qualified and non-qualified workers. A total of 125,021 accidents between 2003 and 2008 involving both blue-collar and white-collar workers were analysed, comparing the variables of occupation, age, company staff, length of service, location of the accident, together with the severity of the accidents. Results showed that lack of experience in the first month is more significant in non-qualified workers and experienced supervisors and that head injuries are more likely to lead to fatalities. The most remarkable similarity was that fatal accidents to and from the worksite are a problem common to both groups of workers.

  9. 26 CFR 52.4682-2 - Qualifying sales.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 17 2010-04-01 2010-04-01 false Qualifying sales. 52.4682-2 Section 52.4682-2... TAXES (CONTINUED) ENVIRONMENTAL TAXES § 52.4682-2 Qualifying sales. (a) In general—(1) Special rules applicable to certain sales. Special rules apply to sales of ODCs in the following cases: (i) Under section...

  10. 6 CFR 25.4 - Designation of qualified anti-terrorism technologies.

    Science.gov (United States)

    2010-01-01

    ... 6 Domestic Security 1 2010-01-01 2010-01-01 false Designation of qualified anti-terrorism... REGULATIONS TO SUPPORT ANTI-TERRORISM BY FOSTERING EFFECTIVE TECHNOLOGIES § 25.4 Designation of qualified anti-terrorism technologies. (a) General. The Under Secretary may Designate as a Qualified Anti-Terrorism...

  11. 12 CFR 619.9270 - Qualified Public Accountant or External Auditor.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Qualified Public Accountant or External Auditor... § 619.9270 Qualified Public Accountant or External Auditor. A qualified public accountant or external... constituted State authority, identifying such person as a certified public accountant; (b) Is licensed to...

  12. Ethernet for Space Flight Applications

    Science.gov (United States)

    Webb, Evan; Day, John H. (Technical Monitor)

    2002-01-01

    NASA's Goddard Space Flight Center (GSFC) is adapting current data networking technologies to fly on future spaceflight missions. The benefits of using commercially based networking standards and protocols have been widely discussed and are expected to include reduction in overall mission cost, shortened integration and test (I&T) schedules, increased operations flexibility, and hardware and software upgradeability/scalability with developments ongoing in the commercial world. The networking effort is a comprehensive one encompassing missions ranging from small University Explorer (UNEX) class spacecraft to large observatories such as the Next Generation Space Telescope (NGST). Mission aspects such as flight hardware and software, ground station hardware and software, operations, RF communications, and security (physical and electronic) are all being addressed to ensure a complete end-to-end system solution. One of the current networking development efforts at GSFC is the SpaceLAN (Spacecraft Local Area Network) project, development of a space-qualifiable Ethernet network. To this end we have purchased an IEEE 802.3-compatible 10/100/1000 Media Access Control (MAC) layer Intellectual Property (IP) core and are designing a network node interface (NNI) and associated network components such as a switch. These systems will ultimately allow the replacement of the typical MIL-STD-1553/1773 and custom interfaces that inhabit most spacecraft. In this paper we will describe our current Ethernet NNI development along with a novel new space qualified physical layer that will be used in place of the standard interfaces. We will outline our plans for development of space qualified network components that will allow future spacecraft to operate in significant radiation environments while using a single onboard network for reliable commanding and data transfer. There will be a brief discussion of some issues surrounding system implications of a flight Ethernet. Finally, we will

  13. 47 CFR 59.4 - Definition of “qualifying carrier”.

    Science.gov (United States)

    2010-10-01

    ... (CONTINUED) INFRASTRUCTURE SHARING § 59.4 Definition of “qualifying carrier”. For purposes of this part, the term “qualifying carrier” means a telecommunications carrier that: (a) Lacks economies of scale or...

  14. The technical qualified expert on radiation protection in Spain

    International Nuclear Information System (INIS)

    Marco Arboli, M.; Rodriguez Suarez, M.

    2002-01-01

    Education and training is considered an important tool for promoting safety culture and improving the level of competence of workers. In the different disciplines involved in Radiation Protection (PR), training programmes are being revised to ensure effective protection of individuals. In the European Union framework, the new normative and its adaptation in the Member States, as well as the past actions in each country, make the community to conclude that harmonization of educational programmes and European recognition of the qualification must be reached. An important point of these actions is the definition of the European Qualified Expert. Article 38 of the EURATOM Basic Safety Standards imposes requirements on training and education of the qualified experts and their exchange within the European Union. Since then, there has been many initiatives to seek to harmonization of the qualified expert requirements. In the Spanish education system, there has been a standard training and competent authority recognition of the high level qualified experts on radiation protection since 1986, whose programme is continuously being updating and improving. Taking into account the European actions to define the qualified expert training requirements, it has been designed an educational course for the Technical Qualified Expert on Radiation Protection. This pilot course has being carried out during May, 2002. The results of this project is shown in this paper. (Author)

  15. 26 CFR 1.860F-1 - Qualified liquidations.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Qualified liquidations. 1.860F-1 Section 1.860F-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Real Estate Investment Trusts § 1.860F-1 Qualified liquidations. A plan of...

  16. 49 CFR 604.7 - Qualified human service organizations.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Qualified human service organizations. 604.7... organizations. (a) A recipient may provide charter service to a qualified human service organization (QHSO) for... disabilities; or (3) With low income. (b) If an organization serving persons described in paragraph (a) of this...

  17. 26 CFR 25.2701-4 - Accumulated qualified payments.

    Science.gov (United States)

    2010-04-01

    ... compound interest from the due date of the payment at a rate not less than the appropriate discount rate is... retained interest conferring a distribution right that was previously valued as a qualified payment right (a “qualified payment interest”), the taxable estate or taxable gifts of the individual holding the...

  18. 26 CFR 48.4041-19 - Exemption for qualified methanol and ethanol fuel.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Exemption for qualified methanol and ethanol....4041-19 Exemption for qualified methanol and ethanol fuel. (a) In general. Under section 4041(b)(2... or use of qualified methanol or ethanol fuel. (b) Qualified methanol or ethanol fuel defined. For...

  19. Space-qualified optical thin films by ion-beam-assisted deposition

    International Nuclear Information System (INIS)

    Hsiao, C.N.; Chen, H.P.; Chiu, P.K.; Lin, Y.W.; Chen, F.Z.; Tsai, D.P.

    2013-01-01

    Optical interference coatings designed for use in a space-grade multispectral assembly in a complementary metal-oxide‐semiconductor sensor were deposited on glass by ion-beam-assisted deposition for a Cassegrain-type space-based remote-sensing platform. The patterned multispectral assembly containing blue, green, red, near infrared, and panchromatic multilayer high/low alternated dielectric band-pass filter arrays in a single chip was fabricated by a mechanical mask and the photolithography process. The corresponding properties of the films were investigated by in situ optical monitoring and spectrometry. It was found that the optical properties were significantly improved by employing ion-beam-assisted deposition. The average transmittances were above 88% for the multispectral assembly, with a rejection transmittance of less than 1% in the spectral range 350–1100 nm. To estimate the optical stability of optical coatings for aerospace applications, a space environment assuming a satellite orbiting the Earth at an altitude of near 800 km was simulated by a Co 60 gamma (γ) radiation test. - Highlights: ►Parameters of optical filters were optimized by using admittance loci analysis. ►Higher index of refraction of films prepared by ion beam assisted deposition. ►The dielectric filters have acceptable resistance after γ radiation exposure

  20. Qualified Health Plan (QHP) Landscape

    Data.gov (United States)

    U.S. Department of Health & Human Services — QHP Landscape Files present basic information about certified Qualified Health Plans and Stand-alone Dental Plans for individuals-families and small businesses...

  1. Multifunctional Self-Aligning Reversible Joint using Space-Qualifiable Structural Fasteners, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group (CRG) proposes the development of a multifunctional reversible attachment scheme to facilitate modular in-space construction. CRG will...

  2. Aging techniques and qualified life for safety system components

    International Nuclear Information System (INIS)

    Weaver, W.W.

    1980-01-01

    Presently, the qualified life objective for Class IE safety system components in nuclear power plants is somewhat of a subjective engineering judgment. When the desired qualified life is ascertained, there are other choices that must be made (which may be influenced by the desired qualified life) such as selecting the aging procedure to use in the qualification process. Adding complexity to the situation is the fact that there are some limitations in aging techniques at the present time. This article presents (1) a discussion of the limitations in aging procedures, (2) the general philosophy of qualification, and (3) a proposed method for specifying a desired qualified life, which uses a probabilistic approach. The probabilistic approach proposed in item 3 can be applied to natural aging programs and eventually to accelerated aging once the present technical difficulties are overcome

  3. The Netherlands: Quality of work and employment of low-qualified workers

    NARCIS (Netherlands)

    Gouw, P.

    2013-01-01

    Based on the Netherlands Working Condition Survey (NEA, TNO) and the available literature, it seems that low-qualified workers experience more labour market problems than middle- or high-qualified workers. The trend in the 2000-2007 period is that the relative number of low qualified workers has

  4. The UK system of recognising qualified experts

    International Nuclear Information System (INIS)

    Bines, W.

    2002-01-01

    EURATOM Basic Safety Standards (BSS) Directives have long included requirements for the involvement of qualified experts, the definition of which has scarcely changed since at least 1976. The Directive requirement, in the definition of qualified expert,, for competent authorities to recognise the capacity to act as a qualified expert has been interpreted by Member States in widely differing ways, ranging from the minimalist or case by case to the highly detailed and prescriptive. In the United Kingdom (UK), the qualified expert for occupational radiation protection is the radiation protection adviser and the competent authority is the Health and Safety Executive (HSE). The Ionising Radiations Regulations 1985, which largely implemented the 1980 BSS Directive, required an employer to appoint one or more radiation protection advisers for the purpose of advising him as to the observance of these Regulations and other health and safety matters in connection with ionising radiation. The Regulations addressed the question of recognition by forbidding an employer to appoint a person as a radiation protection adviser unless: that person was suitably qualified and experienced; the employer had notified the Health and Safety Executive in writing of the intended appointment at least 28 days in advance, giving the name of the person and particulars of his qualifications and experience and the scope of the advice he would be required to give; and the employer had received from HSE an acknowledgement in writing of the notification. This system allowed HSE to follow up and query any apparently unsuitable potential appointments while applying a light overall administrative touch. The Approved Code of Practice supporting the Regulations included advice on the qualifications, experience and qualities that the employer should look for in a suitable radiation protection adviser

  5. 30 CFR 203.43 - To which production do I apply the RSV earned from qualified deep wells or qualified phase 1...

    Science.gov (United States)

    2010-07-01

    ... in water between 200 and 400 meters deep, you begin drilling an original deep well with a perforated... 200 meters deep; (ii) May 18, 2007, for an RSV earned by a qualified deep well on a lease that is located entirely in water more than 200 meters deep; or (iii) The date that the first qualified well that...

  6. 10 CFR 451.4 - What is a qualified renewable energy facility.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false What is a qualified renewable energy facility. 451.4 Section 451.4 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.4 What is a qualified renewable energy facility. In order to qualify for an incentive payment under...

  7. Confidence in leadership among the newly qualified.

    Science.gov (United States)

    Bayliss-Pratt, Lisa; Morley, Mary; Bagley, Liz; Alderson, Steven

    2013-10-23

    The Francis report highlighted the importance of strong leadership from health professionals but it is unclear how prepared those who are newly qualified feel to take on a leadership role. We aimed to assess the confidence of newly qualified health professionals working in the West Midlands in the different competencies of the NHS Leadership Framework. Most respondents felt confident in their abilities to demonstrate personal qualities and work with others, but less so at managing or improving services or setting direction.

  8. 49 CFR 192.285 - Plastic pipe: Qualifying persons to make joints.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Plastic pipe: Qualifying persons to make joints... Materials Other Than by Welding § 192.285 Plastic pipe: Qualifying persons to make joints. (a) No person may make a plastic pipe joint unless that person has been qualified under the applicable joining procedure...

  9. Solar array qualification through qualified analysis

    Science.gov (United States)

    Zijdemans, J.; Cruijssen, H. J.; Wijker, J. J.

    1991-04-01

    To achieve qualification is in general a very expensive exercise. For solar arrays this is done by a dedicated test program through which final qualification is achieved. Due to severe competition on the solar array market, cheaper means are looked for to achieve a qualified product for the customers. One of the methods is to drastically limit the environmental test program and to qualify the solar-array structure against its environmental loads by analysis. Qualification by analysis is possible. The benefits are that a significant amount of development effort can be saved in case such a powerful tool is available. Extensive testing can be avoided thus saving time and money.

  10. Cycle Design of Reverse Brayton Cryocooler for HTS Cable Cooling Using Exergy Analysis

    Science.gov (United States)

    Gupta, Sudeep Kumar; Ghosh, Parthasarathi

    2017-02-01

    The reliability and price of cryogenic refrigeration play an important role in the successful commercialization of High Temperature Superconducting (HTS) cables. For cooling HTS cable, sub-cooled liquid nitrogen (LN2) circulation system is used. One of the options to maintain LN2 in its sub-cooled state is by providing refrigeration with the help of Reverse Brayton Cryo-cooler (RBC). The refrigeration requirement is 10 kW for continuously sub-cooling LN2 from 72 K to 65 K for cooling 1 km length of HTS cable [1]. In this paper, a parametric evaluation of RBC for sub-cooling LN2 has been performed using helium as a process fluid. Exergy approach has been adopted for this analysis. A commercial process simulator, Aspen HYSYS® V8.6 has been used for this purpose. The critical components have been identified and their exergy destruction and exergy efficiency have been obtained for a given heat load condition.

  11. 20 CFR 404.1018b - Medicare qualified government employment.

    Science.gov (United States)

    2010-04-01

    ... AND DISABILITY INSURANCE (1950- ) Employment, Wages, Self-Employment, and Self-Employment Income Work Excluded from Employment § 404.1018b Medicare qualified government employment. (a) General. The work of a... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Medicare qualified government employment. 404...

  12. Low-Income Housing Tax Credit (LIHTC) Qualified Census Tract (QCT)

    Data.gov (United States)

    Department of Housing and Urban Development — It allows to generate tables for Low-Income Housing Tax Credit (LIHTC) Qualified Census Tracts (QCT) and for Difficult Development Areas (DDA). LIHTC Qualified...

  13. 49 CFR 192.283 - Plastic pipe: Qualifying joining procedures.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Plastic pipe: Qualifying joining procedures. 192... Materials Other Than by Welding § 192.283 Plastic pipe: Qualifying joining procedures. (a) Heat fusion... for making plastic pipe joints by a heat fusion, solvent cement, or adhesive method, the procedure...

  14. 17 CFR 210.12-09 - Valuation and qualifying accounts.

    Science.gov (United States)

    2010-04-01

    ... period Column C—Additions (1)—Charged to costs and expenses (2)—Charged to other accounts—describe Column... qualifying accounts and reserves by descriptive title. Group (a) those valuation and qualifying accounts... accounts. 210.12-09 Section 210.12-09 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION...

  15. Angular Positioning Sensor for Space Mechanisms

    Science.gov (United States)

    Steiner, Nicolas; Chapuis, Dominique

    2013-09-01

    Angular position sensors are used on various rotating mechanisms such as solar array drive mechanisms, antenna pointing mechanisms, scientific instruments, motors or actuators.Now a days, potentiometers and encoders are mainly used for angular measurement purposes. Both of them have their own pros and cons.As alternative, Ruag Space Switzerland Nyon (RSSN) is developing and qualifying two innovative technologies of angular position sensors which offer easy implementation, medium to very high lifetime and high flexibility with regards to the output signal shape/type.The Brushed angular position sensor uses space qualified processes which are already flying on RSSN's sliprings for many years. A large variety of output signal shape can be implemented to fulfill customer requirements (digital, analog, customized, etc.).The contactless angular position sensor consists in a new radiation hard Application Specific Integrated Circuit (ASIC) based on the Hall effect and providing the angular position without complex processing algorithm.

  16. 46 CFR 391.6 - Tax treatment of qualified withdrawals.

    Science.gov (United States)

    2010-10-01

    ... accounting whereby (1) payments shall reduce the basis of the property on the day such payments are actually... 46 Shipping 8 2010-10-01 2010-10-01 false Tax treatment of qualified withdrawals. 391.6 Section...-469 FEDERAL INCOME TAX ASPECTS OF THE CAPITAL CONSTRUCTION FUND § 391.6 Tax treatment of qualified...

  17. Space Shuttle Program (SSP) Shock Test and Specification Experience for Reusable Flight Hardware Equipment

    Science.gov (United States)

    Larsen, Curtis E.

    2012-01-01

    As commercial companies are nearing a preliminary design review level of design maturity, several companies are identifying the process for qualifying their multi-use electrical and mechanical components for various shock environments, including pyrotechnic, mortar firing, and water impact. The experience in quantifying the environments consists primarily of recommendations from Military Standard-1540, Product Verification Requirement for Launch, Upper Stage, and Space Vehicles. Therefore, the NASA Engineering and Safety Center (NESC) formed a team of NASA shock experts to share the NASA experience with qualifying hardware for the Space Shuttle Program (SSP) and other applicable programs and projects. Several team teleconferences were held to discuss past experience and to share ideas of possible methods for qualifying components for multiple missions. This document contains the information compiled from the discussions

  18. 42 CFR 436.128 - Coverage for certain qualified aliens.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Coverage for certain qualified aliens. 436.128... Mandatory Coverage of the Categorically Needy § 436.128 Coverage for certain qualified aliens. The agency... § 440.255(c) of this chapter to those aliens described in § 436.406(c) of this subpart. [55 FR 36820...

  19. 26 CFR 1.1092(c)-1 - Qualified covered calls.

    Science.gov (United States)

    2010-04-01

    ... lowest qualified benchmark is determined using the adjusted applicable stock price, as defined in § 1... (CONTINUED) INCOME TAXES Wash Sales of Stock Or Securities § 1.1092(c)-1 Qualified covered calls. (a) In.... Under section 1092(d)(3)(B)(i)(I), stock is personal property if the stock is part of a straddle that...

  20. 26 CFR 1.405-1 - Qualified bond purchase plans.

    Science.gov (United States)

    2010-04-01

    ... purchase plan must conform to the definition of a pension plan in paragraph (b)(1)(i) of § 1.401-1, or the.... Accordingly, even though a qualified bond purchase plan is designed as a pension plan, it need not provide... apply in a nondiscriminatory manner. (ii) A qualified bond purchase plan which is designed as a pension...

  1. Conceptual design of the X-IFU Instrument Control Unit on board the ESA Athena mission

    Science.gov (United States)

    Corcione, L.; Ligori, S.; Capobianco, V.; Bonino, D.; Valenziano, L.; Guizzo, G. P.

    2016-07-01

    Athena is one of L-class missions selected in the ESA Cosmic Vision 2015-2025 program for the science theme of the Hot and Energetic Universe. The Athena model payload includes the X-ray Integral Field Unit (X-IFU), an advanced actively shielded X-ray microcalorimeter spectrometer for high spectral resolution imaging, utilizing cooled Transition Edge Sensors. This paper describes the preliminary architecture of Instrument Control Unit (ICU), which is aimed at operating all XIFU's subsystems, as well as at implementing the main functional interfaces of the instrument with the S/C control unit. The ICU functions include the TC/TM management with S/C, science data formatting and transmission to S/C Mass Memory, housekeeping data handling, time distribution for synchronous operations and the management of the X-IFU components (i.e. CryoCoolers, Filter Wheel, Detector Readout Electronics Event Processor, Power Distribution Unit). ICU functions baseline implementation for the phase-A study foresees the usage of standard and Space-qualified components from the heritage of past and current space missions (e.g. Gaia, Euclid), which currently encompasses Leon2/Leon3 based CPU board and standard Space-qualified interfaces for the exchange commands and data between ICU and X-IFU subsystems. Alternative architecture, arranged around a powerful PowerPC-based CPU, is also briefly presented, with the aim of endowing the system with enhanced hardware resources and processing power capability, for the handling of control and science data processing tasks not defined yet at this stage of the mission study.

  2. Open-Source RTOS Space Qualification: An RTEMS Case Study

    Science.gov (United States)

    Zemerick, Scott

    2017-01-01

    NASA space-qualification of reusable off-the-shelf real-time operating systems (RTOSs) remains elusive due to several factors notably (1) The diverse nature of RTOSs utilized across NASA, (2) No single NASA space-qualification criteria, lack of verification and validation (V&V) analysis, or test beds, and (3) different RTOS heritages, specifically open-source RTOSs and closed vendor-provided RTOSs. As a leader in simulation test beds, the NASA IV&V Program is poised to help jump-start and lead the space-qualification effort of the open source Real-Time Executive for Multiprocessor Systems (RTEMS) RTOS. RTEMS, as a case-study, can be utilized as an example of how to qualify all RTOSs, particularly the reusable non-commercial (open-source) ones that are gaining usage and popularity across NASA. Qualification will improve the overall safety and mission assurance of RTOSs for NASA-agency wide usage. NASA's involvement in space-qualification of an open-source RTOS such as RTEMS will drive the RTOS industry toward a more qualified and mature open-source RTOS product.

  3. Protein crystal growth results from the United States Microgravity Laboratory-1 mission

    Science.gov (United States)

    Delucas, Lawrence J.; Moore, K. M.; Vanderwoerd, M.; Bray, T. L.; Smith, C.; Carson, M.; Narayana, S. V. L.; Rosenblum, W. M.; Carter, D.; Clark, A. D, Jr.

    1994-01-01

    Protein crystal growth experiments have been performed by this laboratory on 18 Space Shuttle missions since April, 1985. In addition, a number of microgravity experiments also have been performed and reported by other investigators. These Space Shuttle missions have been used to grow crystals of a variety of proteins using vapor diffusion, liquid diffusion, and temperature-induced crystallization techniques. The United States Microgravity Laboratory - 1 mission (USML-1, June 25 - July 9, 1992) was a Spacelab mission dedicated to experiments involved in materials processing. New protein crystal growth hardware was developed to allow in orbit examination of initial crystal growth results, the knowledge from which was used on subsequent days to prepare new crystal growth experiments. In addition, new seeding hardware and techniques were tested as well as techniques that would prepare crystals for analysis by x-ray diffraction, a capability projected for the planned Space Station. Hardware that was specifically developed for the USML-1 mission will be discussed along with the experimental results from this mission.

  4. Towards Cryogenic Liquid-Vapor Energy Storage Units for space applications

    Science.gov (United States)

    Afonso, Josiana Prado

    With the development of mechanical coolers and very sensitive cryogenic sensors, it could be interesting to use Energy Storage Units (ESU) and turn off the cryocooler to operate in a free micro vibration environment. An ESU would also avoid cryogenic systems oversized to attenuate temperature fluctuations due to thermal load variations which is useful particularly for space applications. In both cases, the temperature drift must remain limited to keep good detector performances. In this thesis, ESUs based on the high latent heat associated to liquid-vapor phase change to store energy have been studied. To limit temperature drifts while keeping small size cell at low temperature, a potential solution consists in splitting the ESU in two volumes: a low temperature cell coupled to a cryocooler cold finger through a thermal heat switch and an expansion volume at room temperature to reduce the temperature increase occurring during liquid evaporation. To obtain a vanishing temperature drift, a new improvement has been tested using two-phase nitrogen: a controlled valve was inserted between the two volumes in order to control the cold cell pressure. In addition, a porous material was used inside the cell to turn the ESU gravity independent and suitable for space applications. In this case, experiments reveal not fully understood results concerning both energy storage and liquid-wall temperature difference. To capture the thermal influence of the porous media, a dedicated cell with poorly conductive lateral wall was built and operated with two-phase helium. After its characterization outside the saturation conditions (conduction, convection), experiments were performed, with and without porous media, heating at the top or the bottom of the cell with various heat fluxes and for different saturation temperatures. In parallel, a model describing the thermal response for a cell containing liquid and vapor with a porous medium heated at the top ("against gravity") was developed

  5. Digital acquisition and wavelength control of seed laser for space-based Lidar applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I proposes to establish the feasibility of using a space qualifiable Field Programmable Gate Array (FPGA) based digital controller to autonomously...

  6. The practical skills of newly qualified nurses.

    Science.gov (United States)

    Danbjørg, Dorthe Boe; Birkelund, Regner

    2011-02-01

    This paper reports the findings from a study of newly qualified nurses and which subjects the nurses regarded as the most important in order to be able to live up to the requirements of clinical practice, and how they experience their potential for developing practical and moral skills, after the decrease in practical training. A qualitative approach guided the research process and the analysis of the data. The data was collected by participant observation and qualitative interviews with four nurses as informants. The conclusions made in this study are based on the statements and the observations of the newly qualified nurses. Our findings are discussed in relation to the Aristotelian concept and other relevant literature. The main message is that the newly qualified nurses did not feel equipped when they finished their training. This could be interpreted as a direct consequence of the decrease in practical training. Our study also underlines that the way nursing theory is perceived and taught is problematic. The interviews revealed that the nurses think that nursing theories should be applied directly in practice. This misunderstanding is probably also applicable to the teachers of the theories. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. Results from Consultancy Meeting on Qualified Technical Centres

    International Nuclear Information System (INIS)

    Novakovic, Mladen

    2017-01-01

    Qualified Technical Centres (QTC) - Current Situation: •Many Member States (MS) need help dealing with DSRS; •Most seek assistance, which can include funding, through the IAEA; •Technical assistance is provided by various governmental organization and private companies (service providers = SP). QTC - Method of Delivery Numerous MS requests are pressing the IAEA’s capacity to assist: •Use qualified internal and external experts/contractors; •Limited pool for DSRS and need to expand; •Dedicated and specialized equipment; •Mobile hot cell; •Mobile tool kit; •Field operations; •Coordinated approach with Nuclear Security and Safety. Qualified Technical Centres for the Management of DSRS: •The challenge is to scale up the support for safe and secure management of DSRS; •Strengthen existing capacity of some MS to support others and make support more sustainable; •Expands the support that can be readily provided and meet the many needs of MS

  8. 48 CFR 225.872-7 - Industrial security for qualifying countries.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Industrial security for... Agreements and Coordination 225.872-7 Industrial security for qualifying countries. The required procedures... qualifying country sources are in the DoD Industrial Security Regulation DoD 5220.22-R (implemented for the...

  9. The Learning Intentions of Low-Qualified Employees: A Multilevel Approach

    Science.gov (United States)

    Kyndt, Eva; Dochy, Filip; Onghena, Patrick; Baert, Herman

    2013-01-01

    In the continuously changing society and knowledge-intensive economy, the demand for the recurrent updating of competencies is coming to the fore for all employees, including low-qualified employees. Employees are considered low qualified when they do not have a starter qualification for higher education. Although many educational studies have…

  10. 29 CFR 779.386 - Restaurants may qualify as exempt 13(a)(2) establishments.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Restaurants may qualify as exempt 13(a)(2) establishments... Service Establishments Restaurants and Establishments Providing Food and Beverage Service § 779.386 Restaurants may qualify as exempt 13(a)(2) establishments. (a) A restaurant may qualify as an exempt retail or...

  11. Performance estimation of an oil-free linear compressor unit for a new compact 2K Gifford-McMahon cryocooler

    Science.gov (United States)

    Hiratsuka, Y.; Bao, Q.; Y Xu, M.

    2017-12-01

    Since 2012, a new, compact Gifford-McMahon (GM) cryocooler for cooling superconducting single photon detectors (SSPD) has been developed and reported by Sumitomo Heavy Industries, Ltd. (SHI). Also, it was reported that National Institute of Information and Communications Technology (NICT) developed a multi-channel, conduction-cooled SSPD system. However, the size and power consumption reduction becomes indispensable to apply such a system to the optical communication of AdHoc for a mobile system installed in a vehicle. The objective is to reduce the total height of the expander by 33% relative to the existing RDK-101 GM expander and to reduce the total volume of the compressor unit by 50% relative to the existing CNA-11 compressor. In addition, considering the targeted cooling application, we set the design cooling capacity targets of the first and the second stages 1 W at 60 K and 20 mW at 2.3 K respectively. In 2016, Hiratsuka et al. reported that an oil-free compressor was developed for a 2K GM cryocooler. The cooling performance of a 2K GM expander driven by an experimental unit of the linear compressor was measured. No-load temperature less than 2.1 K and the cooling capacity of 20 mW at 2.3 K were successfully achieved with an electric input power of only 1.1 kW. After that, the compressor capsule and the heat exchanger, etc. were assembled into one enclosure as a compressor unit. The total volume of the compressor unit and electrical box was significantly reduced to about 38 L, which was close to the target of 35 L. Also, the sound noise, vibration characteristics, the effect of the compressor unit inclination and the ambient temperature on the cooling performance, were evaluated. The detailed experimental results are discussed in this paper.

  12. Qualified-agent virtue ethics | van Zyl | South African Journal of ...

    African Journals Online (AJOL)

    Qualified-agent virtue ethics provides an account of right action in terms of the virtuous agent. It has become one of the most popular, but also most frequently criticized versions of virtue ethics. Many of the objections rest on the mistaken assumption that proponents of qualified-agent virtue ethics share the same view when it ...

  13. Optoelectronic devices product assurance guideline for space application

    Science.gov (United States)

    Bensoussan, A.; Vanzi, M.

    2017-11-01

    New opportunities are emerging for the implementation of hardware sub-systems based on OptoElectronic Devices (OED) for space application. Since the end of this decade the main players for space systems namely designers and users including Industries, Agencies, Manufacturers and Laboratories are strongly demanding of adequate strategies to qualify and validate new optoelectronics products and sub-systems [1]. The long term space application mission will require to address either inter-satellite link (free space communication, positioning systems, tracking) or intra-satellite connectivity/flexibility/reconfigurability or high volume of data transfer between equipment installed into payload.

  14. 76 FR 2029 - Small Business Investment Companies-Energy Saving Qualified Investments

    Science.gov (United States)

    2011-01-12

    ... 3245-AF86 Small Business Investment Companies--Energy Saving Qualified Investments AGENCY: U.S. Small... Administration (SBA) is setting forth the new defined terms, ``Energy Saving Qualified Investment'' and ``Energy Saving Activities'', for the Small Business Investment Company (SBIC) Program. The new definitions are...

  15. Correlation of United States Medical Licensing Examination and Internal Medicine In-Training Examination performance.

    Science.gov (United States)

    Perez, Jose A; Greer, Sharon

    2009-12-01

    The Internal Medicine In-Training Examination (ITE) is administered during residency training in the United States as a self-assessment and program assessment tool. Performance on this exam correlates with outcome on the American Board of Internal Medicine Certifying examination. Internal Medicine Program Directors use the United States Medical Licensing Examination (USMLE) to make decisions in recruitment of potential applicants. This study was done to determine a correlation of USMLE Steps 1, 2 and 3 results with ITE scores in each level of Internal Medicine training. A retrospective review of all residents graduating from an Internal Medicine program from 1999 to 2006 was done. Subjects included had data for all USMLE Steps and ITE during all years of training. Thirty-one subjects were included in the study. Correlations of USMLE Steps 1, 2 and 3 were done with ITE scores (percent correct) in each year of training. Pearson's correlation coefficient (r) was determined for each pairing and a t test to determine statistical significance of the correlation was done. Statistical significance was defined as P value ITE percent correct in PGY I, II and III were 0.46, 0.55 and 0.51 respectively. Corresponding r values for USMLE Step 2 and ITE percent correct were 0.79, 0.70 and 0.72; for USMLE Step 3 these values were 0.51, 0.37 and 0.51 respectively for each training year. USMLE scores are correlated with ITE scores. This correlation was strongest for USMLE Step 2.

  16. 8 CFR 214.14 - Alien victims of certain qualifying criminal activity.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Alien victims of certain qualifying criminal activity. 214.14 Section 214.14 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS NONIMMIGRANT CLASSES § 214.14 Alien victims of certain qualifying criminal activity. (a...

  17. Technology transfer of military space microprocessor developments

    Science.gov (United States)

    Gorden, C.; King, D.; Byington, L.; Lanza, D.

    1999-01-01

    Over the past 13 years the Air Force Research Laboratory (AFRL) has led the development of microprocessors and computers for USAF space and strategic missile applications. As a result of these Air Force development programs, advanced computer technology is available for use by civil and commercial space customers as well. The Generic VHSIC Spaceborne Computer (GVSC) program began in 1985 at AFRL to fulfill a deficiency in the availability of space-qualified data and control processors. GVSC developed a radiation hardened multi-chip version of the 16-bit, Mil-Std 1750A microprocessor. The follow-on to GVSC, the Advanced Spaceborne Computer Module (ASCM) program, was initiated by AFRL to establish two industrial sources for complete, radiation-hardened 16-bit and 32-bit computers and microelectronic components. Development of the Control Processor Module (CPM), the first of two ASCM contract phases, concluded in 1994 with the availability of two sources for space-qualified, 16-bit Mil-Std-1750A computers, cards, multi-chip modules, and integrated circuits. The second phase of the program, the Advanced Technology Insertion Module (ATIM), was completed in December 1997. ATIM developed two single board computers based on 32-bit reduced instruction set computer (RISC) processors. GVSC, CPM, and ATIM technologies are flying or baselined into the majority of today's DoD, NASA, and commercial satellite systems.

  18. MODELLING AND FAILURE ANALYSIS OF FLEXURE SPRINGS FOR A STIRLING CRYOCOOLER

    Directory of Open Access Journals (Sweden)

    RAJESH V. R.

    2017-04-01

    Full Text Available In the range of milliwatt to a few watts cooling capacity, Stirling cycle and pulse tube coolers are most suitable for producing cryogenic temperatures owing to their eco-friendliness, high efficiency, cooling capacity to mass ratio etc. The compressor of a Stirling cooler is powered by a linear motor. The power piston of the cooler is held in position and moves to and fro with the support of so called flexure springs or flexure bearings. Flexures avoid direct contact between moving parts of the compressor of the cooler. Thus, if designed adequately to withstand fatigue, flexure bearings can easily outlast rolling element bearings and slider bearings. In this work, a computational analysis is used to study the performance of flexure spring by varying the geometrical parameters. Three of the most common spring materials namely, SS304, beryllium copper and spring steel are considered for analysis. The analysis was made by varying the parameters like spiral sweep angle, slot width, number of spirals and disc thickness. The influence of each of these parameters on the fatigue life of the spring has been investigated. The results suggest that flexure springs of three spiral arms would be the ideal choice for the selected cryocooler. The variation of stress developed with respect to different design parameters and fatigue damage factor are presented graphically.

  19. 13 CFR 126.204 - May a qualified HUBZone SBC have affiliates?

    Science.gov (United States)

    2010-01-01

    ... affiliates? 126.204 Section 126.204 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION HUBZONE PROGRAM Requirements to be a Qualified HUBZone SBC § 126.204 May a qualified HUBZone SBC have affiliates? A concern may have affiliates provided that the aggregate size of the concern and all of its...

  20. A comparative reliability analysis of free-piston Stirling machines

    Science.gov (United States)

    Schreiber, Jeffrey G.

    2001-02-01

    A free-piston Stirling power convertor is being developed for use in an advanced radioisotope power system to provide electric power for NASA deep space missions. These missions are typically long lived, lasting for up to 14 years. The Department of Energy (DOE) is responsible for providing the radioisotope power system for the NASA missions, and has managed the development of the free-piston power convertor for this application. The NASA Glenn Research Center has been involved in the development of Stirling power conversion technology for over 25 years and is currently providing support to DOE. Due to the nature of the potential missions, long life and high reliability are important features for the power system. Substantial resources have been spent on the development of long life Stirling cryocoolers for space applications. As a very general statement, free-piston Stirling power convertors have many features in common with free-piston Stirling cryocoolers, however there are also significant differences. For example, designs exist for both power convertors and cryocoolers that use the flexure bearing support system to provide noncontacting operation of the close-clearance moving parts. This technology and the operating experience derived from one application may be readily applied to the other application. This similarity does not pertain in the case of outgassing and contamination. In the cryocooler, the contaminants normally condense in the critical heat exchangers and foul the performance. In the Stirling power convertor just the opposite is true as contaminants condense on non-critical surfaces. A methodology was recently published that provides a relative comparison of reliability, and is applicable to systems. The methodology has been applied to compare the reliability of a Stirling cryocooler relative to that of a free-piston Stirling power convertor. The reliability analysis indicates that the power convertor should be able to have superior reliability

  1. 13 CFR 108.110 - Qualified management.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Qualified management. 108.110... management. An Applicant must show, to the satisfaction of SBA, that its current or proposed management team... or proposed management team has sufficient qualifications, SBA will consider information provided by...

  2. Factor Structure of the Air Force Officer Qualifying Test: Analysis and Comparison

    National Research Council Canada - National Science Library

    Carreta, Thomas

    1998-01-01

    The Air Force Officer Qualifying Test (AFOQT) is used to qualify men and women for commissions in the Air Force, classify them for pilot and navigator jobs, and award Reserve Officer Training Corps (ROTC) scholarships...

  3. Study on the flow nonuniformity in a high capacity Stirling pulse tube cryocooler

    Science.gov (United States)

    You, X.; Zhi, X.; Duan, C.; Jiang, X.; Qiu, L.; Li, J.

    2017-12-01

    High capacity Stirling-type pulse tube cryocoolers (SPTC) have promising applications in high temperature superconductive motor and gas liquefaction. However, with the increase of cooling capacity, its performance deviates from well-accepted one-dimensional model simulation, such as Sage and Regen, mainly due to the strong field nonuniformity. In this study, several flow straighteners placed at both ends of the pulse tube are investigated to improve the flow distribution. A two-dimensional model of the pulse tube based on the computational fluid dynamics (CFD) method has been built to study the flow distribution of the pulse tube with different flow straighteners including copper screens, copper slots, taper transition and taper stainless slot. A SPTC set-up which has more than one hundred Watts cooling power at 80 K has been built and tested. The flow straighteners mentioned above have been applied and tested. The results show that with the best flow straightener the cooling performance of the SPTC can be significantly improved. Both CFD simulation and experiment show that the straighteners have impacts on the flow distribution and the performance of the high capacity SPTC.

  4. ATLAS Physicist in Space

    CERN Multimedia

    Bengt Lund-Jensen

    2007-01-01

    On December 9, the former ATLAS physicist Christer Fuglesang was launched into space onboard the STS-116 Space Shuttle flight from Kennedy Space Center in Florida. Christer worked on the development of the accordion-type liquid argon calorimeter and SUSY simulations in what eventually became ATLAS until summer 1992 when he became one out of six astronaut trainees with the European Space Agency (ESA). His selection out of a very large number of applicants from all over the ESA member states involved a number of tests in order to choose the most suitable candidates. As ESA astronaut Christer trained with the Russian Soyuz programme in Star City outside of Moscow from 1993 until 1996, when he moved to Houston to train for space shuttle missions with NASA. Christer belonged to the backup crew for the Euromir95 mission. After additional training in Russia, Christer qualified as ‘Soyuz return commander’ in 1998. Christer rerouting cables during his second space walk. (Photo: courtesy NASA) During...

  5. One-liter Hg ion clock for space and ground applications

    Science.gov (United States)

    Prestage, John D.; Chung, Sang; Le, Thanh; Beach, Maggie; Maleki, Lute; Tjoelker, Robert L.

    2003-01-01

    We describe the development of a small Hg ion clock suitable for space use. A small clock occupying 1-2 liters volume and producing stability of 10 to the power negative twelve, divided by square root pi would significantly advance the state of space-qualified atomic clocks. Based on recent measurements, this technology should produce long-term stability as good as 10 to the power negative fifteen.

  6. 46 CFR 390.9 - Qualified withdrawals.

    Science.gov (United States)

    2010-10-01

    ..., construction or reconstruction its fair market value. The party must obtain the prior written permission of the... appraisal to be the fair market value of the vessel, at the time of the acquisition, or the actual cost...: (i) The acquisition, construction or reconstruction of a qualified agreement vessel; (ii) The...

  7. 26 CFR 1.401-7 - Forfeitures under a qualified pension plan.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 5 2010-04-01 2010-04-01 false Forfeitures under a qualified pension plan. 1...) INCOME TAX (CONTINUED) INCOME TAXES Pension, Profit-Sharing, Stock Bonus Plans, Etc. § 1.401-7 Forfeitures under a qualified pension plan. (a) General rules. In the case of a trust forming a part of a...

  8. 26 CFR 1.401(a)-11 - Qualified joint and survivor annuities.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 5 2010-04-01 2010-04-01 false Qualified joint and survivor annuities. 1.401(a...)-11 Qualified joint and survivor annuities. (a) General rule—(1) Required provisions. A trust, to...), which is a part of a plan providing for the payment of benefits in any form of a life annuity (as...

  9. Technical aspects: development, manufacture and installation of a cryo-cooled HTS coil system for high-resolution in-vivo imaging of the mouse at 1.5 T.

    Science.gov (United States)

    Ginefri, Jean-Christophe; Poirier-Quinot, Marie; Girard, Olivier; Darrasse, Luc

    2007-09-01

    Signal-to-noise ratio improvement is of major importance to achieve microscopic spatial resolution in magnetic resonance experiments. Magnetic resonance imaging of small animals is particularly concerned since it typically requires voxels of less than (100 microm)(3) to observe the small anatomical structures having size reduction by a factor of more than 10 as compared to human being. The signal-to-noise ratio can be increased by working at high static magnetic field strengths, but the biomedical interest of such high-field systems may be limited due to field-dependent contrast mechanisms and severe technological difficulties. An alternative approach that allows working in clinical imaging system is to improve the sensitivity of the radio-frequency receiver coil. This can be done using small cryogenically operated coils made either of copper or high-temperature superconducting material. We report the technological development of cryo-cooled superconducting coils for high-resolution imaging in a whole-body magnetic resonance scanner operating at 1.5 T. The technological background supporting this development is first addressed, including HTS coil design, simulation tools, cryogenic mean description and electrical characterization procedure. To illustrate the performances of superconducting coils for magnetic resonance imaging at intermediate field strength, in-vivo mouse images of various anatomic sites acquired with a 12 mm diameter cryo-cooled superconducting coil are presented.

  10. Referees check robots after qualifying match at regional robotic competition at KSC

    Science.gov (United States)

    1999-01-01

    Referees check the robots on the floor of the playing field after a qualifying match of the 1999 Southeastern Regional robotic competition at Kennedy Space Center Visitor Complex . Thirty schools from around the country have converged at KSC for the event that pits gladiator robots against each other in an athletic-style competition. The robots have to retrieve pillow- like disks from the floor, as well as climb onto the platform (with flags) and raise the cache of pillows to a height of eight feet. KSC is hosting the event being sponsored by the nonprofit organization For Inspiration and Recognition of Science and Technology, known as FIRST. The FIRST robotics competition is designed to provide students with a hands-on, inside look at engineering and other professional careers.

  11. 26 CFR 20.2056A-2 - Requirements for qualified domestic trust.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Requirements for qualified domestic trust. 20.2056A-2 Section 20.2056A-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) ESTATE AND GIFT TAXES ESTATE TAX; ESTATES OF DECEDENTS DYING AFTER AUGUST 16, 1954 Taxable Estate § 20.2056A-2 Requirements for qualified...

  12. 26 CFR 1.1092(c)-3 - Qualifying over-the-counter options.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Qualifying over-the-counter options. 1.1092(c)-3...-counter options. (a) In general. Under section 1092(c)(4)(B)(i), an equity option is not a qualified covered call option unless it is traded on a national securities exchange that is registered with the...

  13. 26 CFR 11.401(a)-11 - Qualified joint and survivor annuities.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Qualified joint and survivor annuities. 11.401... SECURITY ACT OF 1974 § 11.401(a)-11 Qualified joint and survivor annuities. (a) In general—(1) General rule... annuity (i.e., an annuity requiring survival of the participant or his spouse as a condition for payment...

  14. Innovative Approaches to Development and Ground Testing of Advanced Bimodal Space Power and Propulsion Systems

    International Nuclear Information System (INIS)

    Hill, T.; Noble, C.; Martinell, J.; Borowski, S.

    2000-01-01

    The last major development effort for nuclear power and propulsion systems ended in 1993. Currently, there is not an initiative at either the National Aeronautical and Space Administration (NASA) or the U.S. Department of Energy (DOE) that requires the development of new nuclear power and propulsion systems. Studies continue to show nuclear technology as a strong technical candidate to lead the way toward human exploration of adjacent planets or provide power for deep space missions, particularly a 15,000 lbf bimodal nuclear system with 115 kW power capability. The development of nuclear technology for space applications would require technology development in some areas and a major flight qualification program. The last major ground test facility considered for nuclear propulsion qualification was the U.S. Air Force/DOE Space Nuclear Thermal Propulsion Project. Seven years have passed since that effort, and the questions remain the same, how to qualify nuclear power and propulsion systems for future space flight. It can be reasonably assumed that much of the nuclear testing required to qualify a nuclear system for space application will be performed at DOE facilities as demonstrated by the Nuclear Rocket Engine Reactor Experiment (NERVA) and Space Nuclear Thermal Propulsion (SNTP) programs. The nuclear infrastructure to support testing in this country is aging and getting smaller, though facilities still exist to support many of the technology development needs. By renewing efforts, an innovative approach to qualifying these systems through the use of existing facilities either in the U.S. (DOE's Advance Test Reactor, High Flux Irradiation Facility and the Contained Test Facility) or overseas should be possible

  15. Innovation Approaches to Development and Ground Testing of Advanced Bimodal Space Power and Propulsion Systems

    Energy Technology Data Exchange (ETDEWEB)

    Hill, T.; Noble, C.; Martinell, J. (INEEL); Borowski, S. (NASA Glenn Research Center)

    2000-07-14

    The last major development effort for nuclear power and propulsion systems ended in 1993. Currently, there is not an initiative at either the National Aeronautical and Space Administration (NASA) or the U.S. Department of Energy (DOE) that requires the development of new nuclear power and propulsion systems. Studies continue to show nuclear technology as a strong technical candidate to lead the way toward human exploration of adjacent planets or provide power for deep space missions, particularly a 15,000 lbf bimodal nuclear system with 115 kW power capability. The development of nuclear technology for space applications would require technology development in some areas and a major flight qualification program. The last major ground test facility considered for nuclear propulsion qualification was the U.S. Air Force/DOE Space Nuclear Thermal Propulsion Project. Seven years have passed since that effort, and the questions remain the same, how to qualify nuclear power and propulsion systems for future space flight. It can be reasonably assumed that much of the nuclear testing required to qualify a nuclear system for space application will be performed at DOE facilities as demonstrated by the Nuclear Rocket Engine Reactor Experiment (NERVA) and Space Nuclear Thermal Propulsion (SNTP) programs. The nuclear infrastructure to support testing in this country is aging and getting smaller, though facilities still exist to support many of the technology development needs. By renewing efforts, an innovative approach to qualifying these systems through the use of existing facilities either in the U.S. (DOE's Advance Test Reactor, High Flux Irradiation Facility and the Contained Test Facility) or overseas should be possible.

  16. Innovative Approaches to Development and Ground Testing of Advanced Bimodal Space Power and Propulsion Systems

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Thomas Johnathan; Noble, Cheryl Ann; Noble, C.; Martinell, John Stephen; Borowski, S.

    2000-07-01

    The last major development effort for nuclear power and propulsion systems ended in 1993. Currently, there is not an initiative at either the National Aeronautical and Space Administration (NASA) or the U.S. Department of Energy (DOE) that requires the development of new nuclear power and propulsion systems. Studies continue to show nuclear technology as a strong technical candidate to lead the way toward human exploration of adjacent planets or provide power for deep space missions, particularly a 15,000 lbf bimodal nuclear system with 115 kW power capability. The development of nuclear technology for space applications would require technology development in some areas and a major flight qualification program. The last major ground test facility considered for nuclear propulsion qualification was the U.S. Air Force/DOE Space Nuclear Thermal Propulsion Project. Seven years have passed since that effort, and the questions remain the same, how to qualify nuclear power and propulsion systems for future space flight. It can be reasonable assumed that much of the nuclear testing required to qualify a nuclear system for space application will be performed at DOE facilities as demonstrated by the Nuclear Rocket Engine Reactor Experiment (NERVA) and Space Nuclear Thermal Propulsion (SNTP) programs. The nuclear infrastructure to support testing in this country is aging and getting smaller, though facilities still exist to support many of the technology development needs. By renewing efforts, an innovative approach to qualifying these systems through the use of existing facilities either in the U.S. (DOE's Advance Test Reactor, High Flux Irradiation Facility and the Contained Test Facility) or overseas should be possible.

  17. An Argument for Design Space Reflection

    DEFF Research Database (Denmark)

    Dove, Graham; Halskov, Kim; Hansen, Nicolai Brodersen

    2016-01-01

    We argue that documenting, revisiting and reflecting on the design space of a project provides three important benefits. First it increases our awareness of the constraints introduced by particular design choices. Second, this qualifies our understanding of the way a design space has been filtered...... by design activities. Third we are prompted to challenge these constraints and reconsider disregarded opportunities. To support this argument, we revisit key activities from two projects in our interaction design lab’s portfolio, selected because of the detailed documentation available. We also introduce...... SnapShot, the web-based tool we are developing for this method of design space reflection. Based on these examples, we present a critical discussion and outline areas of future research....

  18. Competence of newly qualified registered nurses from a nursing college

    Directory of Open Access Journals (Sweden)

    BG Morolong

    2005-09-01

    Full Text Available The South African education and training system, through its policy of outcomesbased education and training, has made competency a national priority. In compliance to this national requirement of producing competent learners, the South African Nursing Council ( 1999 B require that the beginner professional nurse practitioners and midwives have the necessary knowledge, skills, attitudes and values which will enable them to render efficient professional service. The health care system also demands competent nurse practitioners to ensure quality in health care. In the light of competency being a national priority and a statutory demand, the research question that emerges is, how competent are the newly qualified registered nurses from a specific nursing college in clinical nursing education? A quantitative, non-experimental contextual design was used to evaluate the competence of newly qualified registered nurses from a specific nursing college. The study was conducted in two phases. The first phase dealt with the development of an instrument together with its manual through the conceptualisation process. The second phase focused on the evaluation of the competency of newly qualified nurses using the instrument based on the steps of the nursing process. A pilot study was conducted to test the feasibility of the items of the instrument. During the evaluation phase, a sample of twenty-six newly qualified nurses was selected by simple random sampling from a target population of thirty-six newly qualified registered nurses. However, six participants withdrew from the study. Data was collected in two general hospitals where the newly qualified registered nurses were working. Observation and questioning were used as data collection techniques in accordance with the developed instrument. Measures were taken to ensure internal validity and reliability of the results. To protect the rights of the participants, the researcher adhered to DENOSA’S (1998

  19. 7 CFR 785.8 - Reports by qualifying States receiving mediation grant funds.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Reports by qualifying States receiving mediation grant... SERVICE AGENCY, DEPARTMENT OF AGRICULTURE SPECIAL PROGRAMS CERTIFIED STATE MEDIATION PROGRAM § 785.8 Reports by qualifying States receiving mediation grant funds. (a) Annual report by certified State...

  20. 41 CFR 102-80.135 - Who is a qualified fire protection engineer?

    Science.gov (United States)

    2010-07-01

    ... protection engineer? 102-80.135 Section 102-80.135 Public Contracts and Property Management Federal Property... qualified fire protection engineer? A qualified fire protection engineer is defined as an individual with a thorough knowledge and understanding of the principles of physics and chemistry governing fire growth...

  1. 26 CFR 1.883-4T - Qualified shareholder stock ownership test (temporary).

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Qualified shareholder stock ownership test... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Foreign Corporations § 1.883-4T Qualified shareholder stock... the stock; (D) If the individual directly owns an interest in a corporation, partnership, trust...

  2. 26 CFR 1.181-3T - Qualified film or television production (temporary).

    Science.gov (United States)

    2010-04-01

    ... season of programming. (3) Exception for certain sexually explicit productions. A production does not... 26 Internal Revenue 3 2010-04-01 2010-04-01 false Qualified film or television production... (continued) § 1.181-3T Qualified film or television production (temporary). (a) In general. The term...

  3. Job satisfaction of overseas-qualified nurses working in Australian hospitals.

    Science.gov (United States)

    Timilsina Bhandari, K K; Xiao, L D; Belan, I

    2015-03-01

    The aims of this study were to explore factors associated with the job satisfaction of overseas-qualified nurses working in public hospitals in South Australia and to compare whether factors associated with job satisfaction of overseas nurses from English-speaking backgrounds differed from those from non-English-speaking backgrounds. Overseas-qualified nurses have become an essential part of the nursing workforce in Australia. Although this nurse population has different expectations and values in relation to their jobs when compared with local nurses, studies on job satisfaction among overseas nurses are scarce. A cross-sectional survey using the Job Satisfaction of Overseas-Qualified Nurses questionnaire was conducted in five major public hospitals in South Australia. One hundred and fifty-one overseas-qualified nurses completed the questionnaire. Four factors were found to influence job satisfaction: Supportive work environment, interpersonal relationships, communication in English, and salary and salary-related benefits. Communication in English was the predominant factor that was associated with job satisfaction in nurses from non-English-speaking backgrounds. This group of nurses also showed a negative correlation between length of stay in Australia and satisfaction with their work environment. Participants' responses to open-ended questions revealed issues relating to discrimination and racism. Supportive work environment, interpersonal relationships, communication in English, and salary and salary-related benefits were major factors associated with job satisfaction in overseas-qualified nurses in this study. Nurses from non-English-speaking backgrounds faced additional challenges in communication in the workplace and in dealing with issues of discrimination and racism. Nurses from non-English-speaking backgrounds need to be supported early in their employment, especially with their communication skills. Consideration also needs to be given to the education

  4. Advanced Compressor for Long Life Space Cryocoolers

    Science.gov (United States)

    1994-11-01

    625 and 718, or beryllium copper. When both high-yield and high- fatigue strength are required, Inconel 718 is usually the material of choice. As shown...with wear debris and life in the case of rubbing seals, and long-term stability and alignment in the case of precision noncontacting clearance seals, are...the bearings’ wear pv, and hence increased life, with decreasing stroke. In summary, the results of the compressor optimization studies showed that a

  5. Qualified operator training in the simulated control room environment

    International Nuclear Information System (INIS)

    Ionescu, Teodor; Studineanu, Emil; Radulescu, Catalina; Bolocan, Gabriel

    2005-01-01

    Full text: Mainly designed for the training of the Cernavoda NPP Unit 2 operators, the virtual simulated environment allows the training of the already qualified operators for Cernavoda NPP Unit 1, adding to the already trained knowledge, the differences which has occurred in the Unit 2 design. Using state-of-the-art computers and displays and qualified software, the virtual simulated panels could offer a viable alternative to classic hardware-based training. This approach allows quick training of the new procedures required by the new configuration of the re-designed operator panels in the main control room of Cernavoda NPP Unit 2. (authors)

  6. Qualified operator training in the simulated control room environment

    International Nuclear Information System (INIS)

    Ionescu, Teodor; Studineanu, Emil; Radulescu, Catalina; Bolocan, Gabriel

    2005-01-01

    Mainly designed for the training of the Cernavoda NPP Unit 2 operators, the virtual simulated environment allows the training of the already qualified operators for Cernavoda NPP Unit 1, adding to the already trained knowledge, the differences which have occurred in the Unit 2 design. Using state-of-the-art computers and displays and qualified software, the virtual simulated panels could offer a viable alternative to classic hardware-based training. This approach allows quick training of the new procedures required by the new configuration of the re-designed operator panels in the main control room of Cernavoda NPP Unit 2. (authors)

  7. Profitability of Qualified-Labour-Power Production

    Science.gov (United States)

    Baldino, Roberto Ribeiro; Cabral, Tânia Cristina Baptista

    2015-01-01

    In Baldino and Cabral (2013) we introduced the concept of qualified labour-power as the commodity produced by the school system. In the present article we outline a quantitative model to evaluate the profit rate of educational programmes. We compare a medical school programme with a teacher education programme at a public university in Brazil,…

  8. Tricks of the trade: time management tips for newly qualified doctors.

    Science.gov (United States)

    Offiah, Gozie; Doherty, Eva

    2018-03-01

    The transition from medical student to doctor is an important milestone. The discovery that their time is no longer their own and that the demands of their job are greater than the time they have available is extremely challenging. At a recent surgical boot camp training programme, 60 first-year surgical trainees who had just completed their internship were invited to reflect on the lessons learnt regarding effective time management and to recommend tips for their newly qualified colleagues. They were asked to identify clinical duties that were considered urgent and important using the time management matrix and the common time traps encountered by newly qualified doctors. The surgical trainees identified several practical tips that ranged from writing a priority list to working on relationships within the team. These tips are generic and so applicable to all newly qualified medial doctors. We hope that awareness of these tips from the outset as against learning them through experience will greatly assist newly qualified doctors. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  9. 'Practising under your own Pin'- a description of the transition experiences of newly qualified midwives.

    Science.gov (United States)

    Avis, Mark; Mallik, Maggie; Fraser, Diane M

    2013-11-01

    Transition experiences of newly qualified midwives were examined in depth during the third phase of a UK evaluation study of midwifery education. The fitness to practise and the retention of newly qualified nursing and midwifery graduates are pressing concerns for health care managers. The advantages of preceptorship are reported in the literature but the content and timing of schemes remain unclear. A semi-structured diary was kept for up to 6 months by 35 newly qualified midwives in 18 work sites covering all countries in the UK. The preceptor and supervisor of midwives for each newly qualified midwife completed short questionnaires about their preceptee's performance, and a further sub-sample of newly qualified midwives and preceptors participated in a semi-structured interview. Data were analysed to elicit aspects of newly qualified midwives transition experiences. Findings confirm that structured preceptorship schemes are not widely available. Newly qualified midwives primarily obtained transition support from members of the midwifery team. Although perceived as competent, there is no demarcation point in becoming confident to practise as a registered practitioner. Implications for managers include the importance of a supportive culture within clinical teams for successful transition and the introduction of structured preceptorship schemes facilitated by appropriate rotation patterns. © 2012 John Wiley & Sons Ltd.

  10. 26 CFR 1.468B-2 - Taxation of qualified settlement funds and related administrative requirements.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 6 2010-04-01 2010-04-01 false Taxation of qualified settlement funds and... Taken § 1.468B-2 Taxation of qualified settlement funds and related administrative requirements. (a) In...) of this section is in lieu of any other taxation of the income of a qualified settlement fund under...

  11. Partners in qualified equipment supply

    International Nuclear Information System (INIS)

    Rygg, D.E.; O'Hare, G.J.

    1993-01-01

    Industry initiatives have been taken to improve procurement practices and commercial dedication programs, formation of procurement engineering groups, emphasis on product quality, and increased engineering involvement in procurement and maintenance of qualified equipment. This poses new challenges for many licensees in terms of resources, product knowledge, and access to information normally held proprietary by equipment suppliers. Alternative approaches to future licensee/Westinghouse relationships which will allow licensees to adapt to the changing environment are discussed. 2 figs

  12. NIRAC: Near Infrared Airglow Camera for the International Space Station

    Science.gov (United States)

    Gelinas, L. J.; Rudy, R. J.; Hecht, J. H.

    2017-12-01

    NIRAC is a space based infrared airglow imager that will be deployed to the International Space Station in late 2018, under the auspices of the Space Test Program. NIRAC will survey OH airglow emissions in the 1.6 micron wavelength regime, exploring the spatial and temporal variability of emission intensities at latitudes from 51° south to 51° north. Atmospheric perturbations in the 80-100 km altitude range, including those produced by atmospheric gravity waves (AGWs), are observable in the OH airglow. The objective of the NIRAC experiment is to make near global measurement of the OH airglow and airglow perturbations. These emissions also provide a bright source of illumination at night, allowing for nighttime detection of clouds and surface characteristics. The instrument, developed by the Aerospace Space Science Applications Laboratory, employs a space-compatible FPGA for camera control and data collection and a novel, custom optical system to eliminate image smear due to orbital motion. NIRAC utilizes a high-performance, large format infrared focal plane array, transitioning technology used in the existing Aerospace Corporation ground-based airglow imager to a space based platform. The high-sensitivity, four megapixel imager has a native spatial resolution of 100 meters at ISS altitudes. The 23° x 23° FOV sweeps out a 150 km swath of the OH airglow layer as viewed from the ISS, and is sensitive to OH intensity perturbations down to 0.1%. The detector has a 1.7 micron cutoff that precludes the need for cold optics and reduces cooling requirements (to 180 K). Detector cooling is provided by a compact, lightweight cryocooler capable of reaching 120K, providing a great deal of margin.

  13. 29 CFR 779.382 - May qualify as exempt 13(a)(2) establishments.

    Science.gov (United States)

    2010-07-01

    ... STANDARDS ACT AS APPLIED TO RETAILERS OF GOODS OR SERVICES Exemptions for Certain Retail or Service Establishments Hotels and Motels § 779.382 May qualify as exempt 13(a)(2) establishments. A hotel or motel establishment may qualify as an exempt retail or service establishment under section 13(a)(2) of the Act...

  14. Note: Space qualified photon counting detector for laser time transfer with picosecond precision and stability.

    Science.gov (United States)

    Prochazka, Ivan; Kodet, Jan; Blazej, Josef

    2016-05-01

    The laser time transfer link is under construction for the European Space Agency in the frame of Atomic Clock Ensemble in Space. We have developed and tested the flying unit of the photon counting detector optimized for this space mission. The results are summarized in this Note. An extreme challenge was to build a detector package, which is rugged, small and which provides long term detection delay stability on picosecond level. The device passed successfully all the tests required for space missions on the low Earth orbits. The detector is extremely rugged and compact. Its long term detection delay stability is excellent, it is better than ±1 ps/day, in a sense of time deviation it is better than 0.5 ps for averaging times of 2000 s to several hours. The device is capable to operate in a temperature range of -55 °C up to +60 °C, the change of the detection delay with temperature is +0.5 ps/K. The device is ready for integration into the space structure now.

  15. Student teams maneuver robots in qualifying match at regional robotic competition at KSC

    Science.gov (United States)

    1999-01-01

    All four robots, maneuvered by student teams behind protective walls, converge on a corner of the playing field during qualifying matches of the 1999 Southeastern Regional robotic competition at Kennedy Space Center Visitor Complex . Thirty schools from around the country have converged at KSC for the event that pits gladiator robots against each other in an athletic-style competition. The robots have to retrieve pillow- like disks from the floor, as well as climb onto the platform (with flags) and raise the cache of pillows to a height of eight feet. KSC is hosting the event being sponsored by the nonprofit organization For Inspiration and Recognition of Science and Technology, known as FIRST. The FIRST robotics competition is designed to provide students with a hands-on, inside look at engineering and other professional careers.

  16. Going beyond "highly-qualified personnel" to "value-added personnel"

    Science.gov (United States)

    Nantel, Marc; Fox, Bradley; Gelsthorpe, Leanne; Hamilton, Roxy; Marshall, Robert; Williamson, Guida

    2005-10-01

    Employers clamour for more "Highly-Qualified Personnel" (HQP) to hire, and photonics is no exception. The challenge facing all new graduates lies in what actually constitutes a Highly-Qualified Person. Yesterday, an HQP was often understood to be a graduate with a Bachelor's, Master's or Ph.D. degree. Today, industry is demanding that an HQP be either a university or college graduate with strong academic standing AND a sound business and communications skill set. In this paper, we introduce the concept of "Value-Added Personnel" (VAP), which marries both scientific and "soft-skills" aspects, and we present a new program in Ontario to produce VAPs.

  17. 26 CFR 1.989(a)-1 - Definition of a qualified business unit.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 10 2010-04-01 2010-04-01 false Definition of a qualified business unit. 1.989... definition of the term “qualified business unit” (QBU) within the meaning of section 989. (2) Effective date... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Export Trade Corporations § 1.989(a)-1 Definition of a...

  18. 9 CFR 85.6 - Interstate movement of pseudorabies vaccinate swine, except swine from qualified negative gene...

    Science.gov (United States)

    2010-01-01

    ... vaccinate swine, except swine from qualified negative gene-altered vaccinated herds, not known to be..., except swine from qualified negative gene-altered vaccinated herds, not known to be infected with or exposed to pseudorabies. Pseudorabies vaccinate swine, except swine from qualified negative gene-altered...

  19. Data systems and computer science space data systems: Onboard networking and testbeds

    Science.gov (United States)

    Dalton, Dan

    1991-01-01

    The technical objectives are to develop high-performance, space-qualifiable, onboard computing, storage, and networking technologies. The topics are presented in viewgraph form and include the following: justification; technology challenges; program description; and state-of-the-art assessment.

  20. Newly qualified teachers´ possibilities to get foothold in a lifelong career course

    DEFF Research Database (Denmark)

    Krøjgaard, Frede; Frederiksen, Lisbeth Angela Lunde

    Keyword: Induction program, newly qualified teachers, NQT, retention, professional development In Contrary to many other countries in Europe Denmark does not have any kind of national program regarding teacher induction program (TIP) or support in general to newly qualified teachers what so ever...

  1. 75 FR 1831 - Seeks Qualified Candidates for the Advisory Committee on Reactor Safeguards

    Science.gov (United States)

    2010-01-13

    ... NUCLEAR REGULATORY COMMISSION Seeks Qualified Candidates for the Advisory Committee on Reactor... Regulatory Commission (NRC) seeks qualified candidates for the Advisory Committee on Reactor Safeguards (ACRS... amended. ACRS provides independent expert advice on matters related to the safety of existing and proposed...

  2. 26 CFR 1.6050S-4 - Information reporting for payments of interest on qualified education loans.

    Science.gov (United States)

    2010-04-01

    ... on qualified education loans. 1.6050S-4 Section 1.6050S-4 Internal Revenue INTERNAL REVENUE SERVICE... Information reporting for payments of interest on qualified education loans. (a) Electronic furnishing of... payments of interest on qualified education loans (furnisher) to the individual to whom it is required to...

  3. ESCC standards, evaluation and qualification of optical fiber connectors for space application

    Science.gov (United States)

    Taugwalder, Frédéric

    2017-11-01

    Optical fiber connectors have been used for the past fifteen years in space application. Reviewing the heritage left from past and current mission, the status of ESCC standards for these components and assemblies will help future use of fiber in space applications. In the frame of the ESA ECI program, Diamond has evaluated and is currently qualifying according to ESCC standards the AVIM and Mini-AVIM connectors. The configuration retained to qualify the connector sets is using a polarization maintaining fiber at 1550nm with a loose tube in PEEK as cable structure. The evaluation has been used to step-stress specific characteristics of the optical fiber connectors with a particular aim at possible failure modes to establish a safety factor for the qualification. The evaluation results presented can be used on a case by case to evaluate special applications that would require to extend the specification. The qualification components can be extended further and a structure for assemblies is proposed in order to simplify fiber optics implementation in space projects.

  4. 26 CFR 1.127-1 - Amounts received under a qualified educational assistance program.

    Science.gov (United States)

    2010-04-01

    ... employee under a qualified educational assistance program described in § 1.127-2, or (2) The value of... Income § 1.127-1 Amounts received under a qualified educational assistance program. (a) Exclusion from.... (c) Amounts received under a nonqualified program. Any amount received under an educational...

  5. 49 CFR 40.281 - Who is qualified to act as a SAP?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Who is qualified to act as a SAP? 40.281 Section... § 40.281 Who is qualified to act as a SAP? To be permitted to act as a SAP in the DOT drug and alcohol.... (2) You must be knowledgeable about the SAP function as it relates to employer interests in safety...

  6. Experimental study of the pressure characteristics in the Stirling refrigerator

    International Nuclear Information System (INIS)

    Hong, Yong Ju; Park, Seong Je; Kim, Hyo Bong; Koh, Deuk Yong

    2001-01-01

    The linear compressor have been widely used for pressure wave generation in the Stirling cryocooler and Stirling type pulse tube cryocooler for tactical purpose. The linear compressor has small and compact structure, and long life due to having non-contact sealing mechanism and the pressure drop through regenerator was ver important role in the motion of displacer in the expander of the Stirling cryocooler. In this study, the characteristic of the linear compressor and the pressure drop through regenerator in the expander was experimentally investigated. The results show resonance of the compressor is very important to get maximum performance and the gas spring force in the compression space of the compressor has effect on the characteristic of resonance and the results show the pressure drop through regenerator is very small than operating pressure change

  7. Gas adsorption/absorption heat switch, phase 1

    Science.gov (United States)

    Chan, C. K.

    1987-01-01

    The service life and/or reliability of far-infrared sensors on surveillance satellites is presently limited by the cryocooler. The life and/or reliability, however, can be extended by using redundant cryocoolers. To reduce parasitic heat leak, each stage of the inactive redundant cryocooler must be thermally isolated from the optical system, while each stage of the active cryocooler must be thermally connected to the system. The thermal break or the thermal contact can be controlled by heat switches. Among different physical mechanisms for heat switching, mechanically activated heat switches tend to have low reliability and, furthermore, require a large contact force. Magnetoresistive heat switches are, except at very low temperatures, of very low efficiency. Heat switches operated by the heat pipe principle usually require a long response time. A sealed gas gap heat switch operated by an adsorption pump has no mechanical motion and should provide the reliability and long lifetime required in long-term space missions. Another potential application of a heat switch is the thermal isolation of the optical plane during decontamination.

  8. Design And Tests Of A Superconducting Magnet With A Cryocooler For The Ion Source Decris-sc

    CERN Document Server

    Datskov, V I; Bekhterev, V V; Bogomolov, S L; Bondarenko, P G; Dmitriev, S N; Drobin, V M; Efremov, A A; Iakovlev, B I; Leporis, M; Malinowski, H; Nikiforov, S A; Paschenko, S V; Seleznev, V V; Shishov, Yu A; Tsvineva, G P; Yazvitsky, N Yu

    2004-01-01

    A superconducting magnet system (SMS) for the multicharged ion source DECRIS-SC was designed and manufactured at the Joint Institute for Nuclear Research. Successful tests of the SMS were conducted in late 2003 - early 2004. The peculiarities of this system are stipulated by using of a cryocooler 1 W in power for the cryostabilization of the magnet, and also by a special configuration of the magnetic field demanded for the source of ions. Four coils ensure induction of a magnetic field on the axes of the source of up to 3T (the mirror ratio of ~6) which considerably extends possibilities of the ion source from the point of view of producing intense highly charged ion beams. The problem of compensating large forces of interaction between the coils and surrounding iron yoke in this magnet has been successfully solved, and a reliable suspension of the magnet in a cryostat realized. For compounding of the windings working in vacuum at indirect cryostabilization prepreg is used. There has been applied a new techno...

  9. Doctors qualifying from United Kingdom medical schools during the calendar years 1977 and 1983.

    Science.gov (United States)

    Parkhouse, J; Parkhouse, H F

    1989-01-01

    At the conclusion of undergraduate medical education in the United Kingdom most students pass a university qualifying examination and obtain a degree in medicine and surgery. Some students pass an external non-university qualifying examination in medicine as an alternative to obtaining a degree, and some do both. The degree may be obtained in the same year as the non-university qualifying examination, or in a different year. Some students from a medical school intake qualify in a later year than expected, for various reasons. Data from university, Health Department and other sources may relate to the academic year, the calendar year, or a fixed date such as 30 September. It is not a simple exercise, therefore, to define the exact number of people who qualify to practise medicine, for the first time, in any given 'year'. In counting qualifiers from individual medical schools, the problems are further compounded by the movement of students between the preclinical and clinical stages of the course, particularly from Oxford and Cambridge to London teaching hospitals. This paper analyses the situation for the calendar years 1977 and 1983, showing a decline in the number of students obtaining double (i.e. both university and non-university) qualifications. The number of UK graduates not registering with the General Medical Council to practise, at least for a time, in the UK was small, and the population base compiled for Medical Career Research Group studies was reasonably accurate in each of the 2 years examined.

  10. Space nuclear power plant technology development philosophy for a ground engineering phase

    International Nuclear Information System (INIS)

    Buden, D.; Trapp, T.J.; Los Alamos National Lab., NM)

    1985-01-01

    The development of a space qualified nuclear power plant is proceeding from the technical assessment and advancement phase to the ground engineering phase. In this new phase, the selected concept will be matured by the completion of activities needed before protoflight units can be assembled and qualified for first flight applications. This paper addresses a possible philosophy to arrive at the activities to be performed during the ground engineering phase. The philosophy is derived from what we believe a potential user of nuclear power would like to see completed before commitment to a flight development phase. 5 references

  11. Space nuclear power plant technology development philosophy for a ground engineering phase

    International Nuclear Information System (INIS)

    Buden, D.; Trapp, T.J.

    1985-01-01

    The development of a space qualified nuclear power plant is proceeding from the Technical Assessment and Advancement Phase to the Ground Engineering Phase. In this new phase, the selected concept will be matured by the completion of activities needed before protoflight units can be assembled and qualified for first flight applications. This paper addresses a possible philosophy to arrive at the activities to be performed during the Ground Engineering Phase. The philosophy is derived from what we believe a potential user of nuclear power would like to see completed before commitment to a flight development phase

  12. High Efficiency Regenerative Helium Compressor, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Helium plays several critical rolls in spacecraft propulsion. High pressure helium is commonly used to pressurize propellant fuel tanks. Helium cryocoolers can be...

  13. 26 CFR 1.1293-1 - Current taxation of income from qualified electing funds.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Current taxation of income from qualified electing funds. 1.1293-1 Section 1.1293-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... Losses § 1.1293-1 Current taxation of income from qualified electing funds. (a) In general. [Reserved] (1...

  14. PERFORMANCE ENHANCEMENT OF A MINIATURE STIRLING CRYOCOOLER WITH A MULTI MESH REGENERATOR DESIGN

    Directory of Open Access Journals (Sweden)

    KISHOR KUMAR V. V.

    2017-06-01

    Full Text Available A parametric study has been carried out using the software REGEN 3.3 to optimize the regenerator of a miniature Stirling cryocooler operating with a warm end temperature of 300 K and cold end temperature of 80 K. Regenerator designs which produce the maximum coefficient of performance (COP of the system is considered as an optimized regenerator. The length and diameter of the regenerator were fixed from the cooler system requirements. Single mesh regenerators made of 200, 250, 300, 400 and 450 Stainless Steel wire meshes were considered and the optimum phase angle and mesh size were obtained. A maximum COP of 0.1475 was obtained for 300 mesh regenerator at 70° phase angle. Then multi mesh regenerators were considered with finer mesh on the cold end and coarser mesh on the hot end. The optimum size and length of each mesh in the multi mesh regenerator and the optimum phase angle were calculated. The maximum COP of 0.156 was obtained for 200 300-400 multi mesh regenerator at 70° phase angle. The COP and net refrigeration obtained for an optimized multi mesh regenerator was found to be significantly higher than that of a single mesh regenerator. Thus a multi mesh regenerator design with a proper combination of regenerator mesh size and length can enhance the regenerator effectiveness.

  15. Business Context of Space Tourism

    Science.gov (United States)

    Schmitt, Harrison H.

    2003-01-01

    Broadly speaking, two types of potential commercial activity in space can be defined. First, there are those activities that represent an expansion and improvement on services with broad existing commercial foundations such as telecommunications. The second type of potential commercial activity in space is one that may offer a type of service with few or any existing commercial foundations such as space-based remote sensing. Space tourism clearly belongs in the first category of potential commercial activity in space. Roles in cooperation with the private sector that might be considered for NASA include 1) acceleration of the ``Professional-in Space'' initiative, 2) research and technology developments related to a) a ``Tourist Destination Module'' for the Space Station, b) an ``Extra Passengers Module'' for the payload bay of the Space Shuttle, and c) a ``Passenger-rated Expendable Launch Vehicle,'' 3) definition of criteria for qualifying candidate space tourists, and 4) initiatives to protect space tourism from unreasonable tort litigation. As baseline information for establishing fees, the cost of a possible tourist flight should be fully and objectively delineated. If it is correct that the marginal cost of each Space Shuttle flight to Earth-orbit is about $100 million and the effective Shuttle payload is about 50,000 pounds, then the marginal cost would be roughly $2,000 per pound.

  16. Continuing Development for Free-Piston Stirling Space Power Systems

    Science.gov (United States)

    Peterson, Allen A.; Qiu, Songgang; Redinger, Darin L.; Augenblick, John E.; Petersen, Stephen L.

    2004-02-01

    Long-life radioisotope power generators based on free-piston Stirling engines are an energy-conversion solution for future space applications. The high efficiency of Stirling machines makes them more attractive than the thermoelectric generators currently used in space. Stirling Technology Company (STC) has been developing free-piston Stirling machines for over 30 years, and its family of Stirling generators is ideally suited for reliable, maintenance-free operation. This paper describes recent progress and status of the STC RemoteGen™ 55 W-class Stirling generator (RG-55), presents an overview of recent testing, and discusses how the technology demonstration design has evolved toward space-qualified hardware.

  17. Predictors of Self-Directed Learning for Low-Qualified Employees: A Multi-Level Analysis

    Science.gov (United States)

    Raemdonck, Isabel; van der Leeden, Rien; Valcke, Martin; Segers, Mien; Thijssen, Jo

    2012-01-01

    Purpose: This study aims to examine which variables at the level of the individual employee and at the company level are predictors of self-directed learning in low-qualified employees. Methodology: Results were obtained from a sample of 408 low-qualified employees from 35 different companies. The companies were selected from the energy sector,…

  18. Attempting to Predict Success in the Qualifying Round of the International Chemistry Olympiad

    Science.gov (United States)

    Urhahne, Detlef; Ho, Lok Hang; Parchmann, Ilka; Nick, Sabine

    2012-01-01

    The aim of this study was trying to predict success in the qualifying round for the International Chemistry Olympiad (IChO) on the basis of the expectancy-value model of achievement motivation by Eccles et al. The investigation with 52 participants, including 14 females, was conducted during the third of four qualifying rounds of the IChO in…

  19. 7 CFR 1466.11 - Technical services provided by qualified personnel not affiliated with USDA.

    Science.gov (United States)

    2010-01-01

    ... not affiliated with USDA. 1466.11 Section 1466.11 Agriculture Regulations of the Department of... OPERATIONS ENVIRONMENTAL QUALITY INCENTIVES PROGRAM Contracts and Payments § 1466.11 Technical services provided by qualified personnel not affiliated with USDA. (a) NRCS may use the services of qualified TSPs...

  20. Dietary habits of obese patients qualified for bariatric procedures.

    Science.gov (United States)

    Jastrzebska-Mierzyńska, Marta; Ostrowska, Lucyna; Hady, Hady Razak; Dadan, Jacek

    2014-01-01

    Patients with obesity, including morbid obesity, commit numerous dietary mistakes. They prefer high-energy diets, but of poor nutritional value. Patients qualified for bariatric procedures show deficiencies in vitamins and minerals due to insufficient intake of vegetables, fruit and whole grain products. Analysis of dietary habits in morbidly obese patients prepared for bariatric surgery, including assessment of eating style and frequency of consumption of certain products. The study group contained 39 people aged 18 - 65 years, who were surveyed with a questionnaire elaborated in the Department of Clinical Dietetics and Nutrition, Medical University of Bialystok. The following factors were assessed: number of meals, snacking between meals and eating at night, types of snacks eaten, and frequency of consumption of certain foods. Results were analyzed using Statistica 9.0. The majority of surveyed men (41.7%) ate three meals a day, whereas most women (40.7%) had at least 4 meals a day. Nearly 85% of the respondents admitted snacking between meals, mainly eating fruit, sweets and sandwiches. Whole grain cereal, milk and dairy products, fish, fruit, vegetables and pulses appeared in diet of patients qualified for treatment of obesity very rarely. Dietary habits of obese patients qualified for bariatric procedures are not consistent with recommendations. Therefore, these patients should receive nutritional education in order to foster proper eating habits that will help in the postoperative nutrition.

  1. Liquid Nitrogen Zero Boiloff Testing

    Science.gov (United States)

    Plachta, David; Feller, Jeffrey; Johnson, Wesley; Robinson, Craig

    2017-01-01

    Cryogenic propellants such as liquid hydrogen (LH2) and liquid oxygen (LO2) are a part of NASAs future space exploration due to their high specific impulse for rocket motors of upper stages suitable for transporting 10s to 100s of metric tons of payload mass to destinations outside of low earth orbit and for their return. However, the low storage temperatures of LH2 and LO2 cause substantial boil-off losses for missions with durations greater than several months. These losses can be eliminated by incorporating high performance cryocooler technology to intercept heat load to the propellant tanks and modulating the cryocooler to control tank pressure. The active thermal control technology being developed by NASA is the reverse turbo-Brayton cycle cryocooler and its integration to the propellant tank through a distributed cooling tubing network coupled to the tank wall. This configuration was recently tested at NASA Glenn Research Center, in a vacuum chamber and cryo-shroud that simulated the essential thermal aspects of low Earth orbit, its vacuum and temperature. Testing consisted of three passive tests with the active cryo-cooler system off, and 7 active tests, with the cryocooler powered up. The test matrix included zero boil-off tests performed at 90 full and 25 full, and several demonstrations at excess cooling capacity and reduced cooling capacity. From this, the tank pressure response with varied cryocooler power inputs was determined. This test series established that the active cooling system integrated with the propellant tank eliminated boil-off and robustly controlled tank pressure.

  2. Free-piston Stirling technology for space power

    Science.gov (United States)

    Slaby, Jack G.

    1989-01-01

    An overview is presented of the NASA Lewis Research Center free-piston Stirling engine activities directed toward space power. This work is being carried out under NASA's new Civil Space Technology Initiative (CSTI). The overall goal of CSTI's High Capacity Power element is to develop the technology base needed to meet the long duration, high capacity power requirements for future NASA space missions. The Stirling cycle offers an attractive power conversion concept for space power needs. Discussed here is the completion of the Space Power Demonstrator Engine (SPDE) testing-culminating in the generation of 25 kW of engine power from a dynamically-balanced opposed-piston Stirling engine at a temperature ratio of 2.0. Engine efficiency was approximately 22 percent. The SPDE recently has been divided into two separate single-cylinder engines, called Space Power Research Engine (SPRE), that now serve as test beds for the evaluation of key technology disciplines. These disciplines include hydrodynamic gas bearings, high-efficiency linear alternators, space qualified heat pipe heat exchangers, oscillating flow code validation, and engine loss understanding.

  3. Experience in initial training required for the recognition of the qualified RP expert in Spain

    International Nuclear Information System (INIS)

    Rodriguez Suarez, M.; Marco Arboli, M.; Menarguez, J.

    2003-01-01

    An important point of the actions inside the European framework to achieve the harmonisation of the training programmes and recognition was included in the European directive 96/29/Euratom which includes definition and specific tasks of the European Qualified Expert on Radiation Protection (RP). Basic syllabus for training of those experts was developed in the communication 98/C 133/03 concerning BSS applications. Although, in the Spanish education system, the training and recognition requirements of the high level qualified experts on RP was defined since 1977, until 2001, the figure of the Technical Qualified Expert on RP does not appear in the legal framework. In December 2002, a new regulation of the Spanish Regulatory Body, CSN, about qualifications to obtain the recognition of RP Expert in Spain (both high qualified and technical RP experts) was published. Concerning the qualified expert on RP, (RP Officer), responsible of the RP Service, which takes charge of the effective protection and advise radioactive and nuclear facilities in Rp aspects,has to be authorised by the regulatory body. to obtain the RP officer diploma, conceded by the CSN, an initial training of 300 hours and a three-year minimum experience are required (for X-ray installation a 6-month experience is enough). The technical qualified expert on RP is the worker who carried out the tasks in the a RP Service under the supervision of the RP officer. A Technician Qualified Expert on RP does not need an specific accreditation of the Regulatory Body, but an initial RP training and a three-month minimum experience are required and has hold a certificate by the RP officer. Continuous training is also required and as well has to receive a certificate from the RP officer. Since 1977, The Institute for energy Studies has been implementing specific training courses for those professionals who want to obtain the diploma of RP officer (high degree qualified RP expert), conceded by the CSN. Since then

  4. 26 CFR 1.221-1 - Deduction for interest paid on qualified education loans after December 31, 2001.

    Science.gov (United States)

    2010-04-01

    ... Individuals § 1.221-1 Deduction for interest paid on qualified education loans after December 31, 2001. (a) In... interest paid by the taxpayer during the taxable year on a qualified education loan. See paragraph (b)(4... paid on qualified education loans after December 31, 2001, in taxable years ending after December 31...

  5. Evaluation of Magnetoresistive RAM for Space Applications

    Science.gov (United States)

    Heidecker, Jason

    2014-01-01

    Magnetoresistive random-access memory (MRAM) is a non-volatile memory that exploits electronic spin, rather than charge, to store data. Instead of moving charge on and off a floating gate to alter the threshold voltage of a CMOS transistor (creating different bit states), MRAM uses magnetic fields to flip the polarization of a ferromagnetic material thus switching its resistance and bit state. These polarized states are immune to radiation-induced upset, thus making MRAM very attractive for space application. These magnetic memory elements also have infinite data retention and erase/program endurance. Presented here are results of reliability testing of two space-qualified MRAM products from Aeroflex and Honeywell.

  6. Creating Highly Qualified Teachers: Maximizing University Resources to Provide Professional Development in Rural Areas

    Science.gov (United States)

    Mollenkopf, Dawn L.

    2009-01-01

    The "highly qualified teacher" requirement of No Child Left Behind has put pressure on rural school districts to recruit and retain highly qualified regular and special education teachers. If necessary, they may utilize uncertified, rural teachers with provisional certification; however, these teachers may find completing the necessary…

  7. 7 CFR 636.18 - Technical services provided by qualified personnel not affiliated with USDA.

    Science.gov (United States)

    2010-01-01

    ... HABITAT INCENTIVES PROGRAM § 636.18 Technical services provided by qualified personnel not affiliated with... affiliated with USDA. 636.18 Section 636.18 Agriculture Regulations of the Department of Agriculture... provided by qualified personnel not affiliated with USDA may include, but is not limited to: Conservation...

  8. Development of Space Qualified Microlens Arrays for Solar Cells Used on Satellite Power Systems

    Directory of Open Access Journals (Sweden)

    Ömer Faruk Keser

    2017-08-01

    Full Text Available The power system, one of the main systems of satellite, provides energy required for the satellite. Solar cells are also the most used energy source in the power system. The third generation multi-junction solar cells are known as the ones with highest performance. One of the methods to increase the performance of the solar cells is anti-reflective surface coatings with the Micro Lens Array-MLA. It's expected that satellite technologies has high power efficiency and low mass. The space environment has many effects like atomic oxygen, radiation and thermal cycles. Researches for increasing the solar cells performance shows that MLA coated solar cell has increased light absorption performance and less cell heating with very low additional mass. However, it is established that few studies on MLA coatings of solar cells are not applicable on space platforms. In this study, the process of development of MLA which is convenient to space power systems is investigated in a methodological way. In this context, a method which is developed based on MLA coatings of multi-junction solar cells for satellite power systems is presented.

  9. Validation of mentorship model for newly qualified professional ...

    African Journals Online (AJOL)

    Newly qualified professional nurses (NQPNs) allocated to community health care services require the use of validated model to practice independently. Validation was done to adapt and assess if the model is understood and could be implemented by NQPNs and mentors employed in community health care services.

  10. Simulation used to qualify nuclear waste glass for disposal

    International Nuclear Information System (INIS)

    Reimus, T.W.; Kuhn, W.L.

    1987-07-01

    A hypothetical vitrification system was simulated errors associated with controlling and predicting the composition of the nuclear waste glass produced in the system. The composition of the glass must fall within certain limits to qualify for permanent geologic disposal. The estimated error in predicting the concentrations of various constituents in the glass was 2% to 8%, depending on the strategy for sampling and analyzing the feed and on the assumed magnitudes of the process uncertainties. The estimated error in controlling the glass composition was 2% to 9%, depending on the strategy for sampling and analyzing the waste and on the assumed magnitudes of the uncertainties. This work demonstrates that simulation techniques can be used to assist in qualifying nuclear waste glass for disposal. 3 refs., 2 figs., 4 tabs

  11. 12 CFR 617.7125 - How should a qualified lender determine the effective interest rate?

    Science.gov (United States)

    2010-01-01

    ... effective interest rate? 617.7125 Section 617.7125 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM BORROWER RIGHTS Disclosure of Effective Interest Rates § 617.7125 How should a qualified lender determine the effective interest rate? (a) A qualified lender must calculate the effective interest rate on...

  12. 12 CFR 574.8 - Qualified stock issuances by undercapitalized savings associations or holding companies.

    Science.gov (United States)

    2010-01-01

    ... voting stock of the issuing undercapitalized savings association or savings and loan holding company. (8... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Qualified stock issuances by undercapitalized... SUPERVISION, DEPARTMENT OF THE TREASURY ACQUISITION OF CONTROL OF SAVINGS ASSOCIATIONS § 574.8 Qualified stock...

  13. Exploring selection and recruitment processes for newly qualified nurses: a sequential-explanatory mixed-method study.

    Science.gov (United States)

    Newton, Paul; Chandler, Val; Morris-Thomson, Trish; Sayer, Jane; Burke, Linda

    2015-01-01

    To map current selection and recruitment processes for newly qualified nurses and to explore the advantages and limitations of current selection and recruitment processes. The need to improve current selection and recruitment practices for newly qualified nurses is highlighted in health policy internationally. A cross-sectional, sequential-explanatory mixed-method design with 4 components: (1) Literature review of selection and recruitment of newly qualified nurses; and (2) Literature review of a public sector professions' selection and recruitment processes; (3) Survey mapping existing selection and recruitment processes for newly qualified nurses; and (4) Qualitative study about recruiters' selection and recruitment processes. Literature searches on the selection and recruitment of newly qualified candidates in teaching and nursing (2005-2013) were conducted. Cross-sectional, mixed-method data were collected from thirty-one (n = 31) individuals in health providers in London who had responsibility for the selection and recruitment of newly qualified nurses using a survey instrument. Of these providers who took part, six (n = 6) purposively selected to be interviewed qualitatively. Issues of supply and demand in the workforce, rather than selection and recruitment tools, predominated in the literature reviews. Examples of tools to measure values, attitudes and skills were found in the nursing literature. The mapping exercise found that providers used many selection and recruitment tools, some providers combined tools to streamline process and assure quality of candidates. Most providers had processes which addressed the issue of quality in the selection and recruitment of newly qualified nurses. The 'assessment centre model', which providers were adopting, allowed for multiple levels of assessment and streamlined recruitment. There is a need to validate the efficacy of the selection tools. © 2014 John Wiley & Sons Ltd.

  14. Mars Atmospheric In Situ Resource Utilization Projects at the Kennedy Space Center

    Science.gov (United States)

    Muscatello, A. C.; Hintze, P. E.; Caraccio, A. J.; Bayliss, J. A.; Karr, L. J.; Paley, M. S.; Marone, M. J.; Gibson, T. L.; Surma, J. M.; Mansell, J. M.; hide

    2016-01-01

    The atmosphere of Mars, which is approximately 95% carbon dioxide (CO2), is a rich resource for the human exploration of the red planet, primarily by the production of rocket propellants and oxygen for life support. Three recent projects led by NASA's Kennedy Space Center have been investigating the processing of CO2. The first project successfully demonstrated the Mars Atmospheric Processing Module (APM), which freezes CO2 with cryocoolers and combines sublimated CO2 with hydrogen to make methane and water. The second project absorbs CO2 with Ionic Liquids and electrolyzes it with water to make methane and oxygen, but with limited success so far. A third project plans to recover up to 100% of the oxygen in spacecraft respiratory CO2. A combination of the Reverse Water Gas Shift reaction and the Boudouard reaction eventually fill the reactor up with carbon, stopping the process. A system to continuously remove and collect carbon is under construction.

  15. Mars Atmospheric In Situ Resource Utilization Projects at the Kennedy Space Center

    Science.gov (United States)

    Muscatello, Anthony; Hintze, Paul; Meier, Anne; Bayliss, Jon; Karr, Laurel; Paley, Steve; Marone, Matt; Gibson, Tracy; Surma, Jan; Mansell, Matt; hide

    2016-01-01

    The atmosphere of Mars, which is 96 percent carbon dioxide (CO2), is a rich resource for the human exploration of the red planet, primarily by the production of rocket propellants and oxygen for life support. Three recent projects led by NASAs Kennedy Space Center have been investigating the processing of CO2. The first project successfully demonstrated the Mars Atmospheric Processing Module (APM), which freezes CO2 with cryocoolers and combines sublimated CO2 with hydrogen to make methane and water. The second project absorbs CO2 with Ionic Liquids and electrolyzes it with water to make methane and oxygen, but with limited success so far. A third project plans to recover up to 100 of the oxygen in spacecraft respiratory CO2. A combination of the Reverse Water Gas Shift reaction and the Boudouard reaction eventually fill the reactor up with carbon, stopping the process. A system to continuously remove and collect carbon has been tested with encouraging results.

  16. TopWorx/GO switch new generation nuclear qualified proximity position sensors

    International Nuclear Information System (INIS)

    Merrifield, G.

    2011-01-01

    An overview of the benefits of installing TopWorx/GO Nuclear Qualified Proximity Position Sensors instead of traditional mechanical switches. Mechanical switches have been the standard for the nuclear industry for years, but that is only because of lack of competition. Because of multiple moving parts, three-piece design, and new low current control systems, mechanical switches are susceptible to a host of environmental factors that cause them to break and/or fail. TopWorx/GO Switch is a smaller, rugged, dependable, one-piece Stainless Steel proximity position sensor that that exceeds CANDU and Global Qualification Levels, easily replacing mechanical switches. It is the only position sensor to meet or exceed Westinghouse AP 1000 specifications as well. Nuclear facilities save money in maintenance reductions, extended PM's and reduction in 'Man REM' hours. This is achieved by not having to service and replace GO Switch position sensors as often as mechanical switches, since their qualified life is 100 years +1 Post Accident submerged. Plant safety is increased due to less switch failure, higher qualification testing levels, repeatability and longer qualified life. (author)

  17. 42 CFR 416.26 - Qualifying for an agreement.

    Science.gov (United States)

    2010-10-01

    ..., where State law requires licensure, the ASC complies with State licensure requirements; and (3) The ASC.... (c) Acceptance of the ASC as qualified to furnish ambulatory surgical services. If CMS determines... its authorized representative; and (2) File them with CMS. (e) Acceptance by CMS. If CMS accepts the...

  18. 26 CFR 1.465-27 - Qualified nonrecourse financing.

    Science.gov (United States)

    2010-04-01

    ... partnership; incidental property. (i) X is a limited liability company that is classified as a partnership for.... (i) UTP1 and UTP2, both limited liability companies classified as partnerships, are the only general... as qualified nonrecourse financing. (4) Partnership liability. For purposes of section 465(b)(6) and...

  19. 30 CFR 75.153 - Electrical work; qualified person.

    Science.gov (United States)

    2010-07-01

    ... Mine Safety and Health Districts at regular intervals, or as demand requires. (d) A score of at least... Section 75.153 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Qualified and Certified Persons § 75...

  20. 26 CFR 1.414(r)-1 - Requirements applicable to qualified separate lines of business.

    Science.gov (United States)

    2010-04-01

    ... lines of business. 1.414(r)-1 Section 1.414(r)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... Plans, Etc. § 1.414(r)-1 Requirements applicable to qualified separate lines of business. (a) In general. Section 414(r) prescribes the conditions under which an employer is treated as operating qualified...

  1. How to manage MTTF larger than 30,000hr on rotary cryocoolers

    Science.gov (United States)

    Cauquil, Jean-Marc; Seguineau, Cédric; Martin, Jean-Yves; Van-Acker, Sébastien; Benschop, Tonny

    2017-05-01

    The cooled IR detectors are used in a wide range of applications. Most of the time, the cryocoolers are one of the components dimensioning the lifetime of the system. Indeed, Stirling coolers are mechanical systems where wear occurs on millimetric mechanisms. The exponential law classically used in electronics for Mean Time to Failure (MTTF) calculation cannot be directly used for mechanical devices. With new applications for thermal sensor like border surveillance, an increasing reliability has become mandatory for rotary cooler. The current needs are above several tens of thousands of continuous hour of cooling. Thales Cryogenics made specific development on that topic, for both linear and rotary applications. The time needed for validating changes in processes through suited experimental design is hardly affordable by following a robust and rigorous standard scientific approach. The targeted Mean Time to Failure (MTTF) led us to adopt an innovative approach to keep development phases in line with expected time to market. This innovative approach is today widespread on all of Thales Cryogenics rotary products and results in a proven increase of MTTF for RM2, RM3 and recently RM1. This paper will then focused on the current MTTF figures measured on RM1, RM2 and RM3. After explaining the limit of a conventional approach, the paper will then describe the current method. At last, the authors will explain how these principles are taken into account for the new SWaP rotary cooler of Thales Cryogénie SAS.

  2. Space Fission Reactor Structural Materials: Choices Past, Present and Future

    International Nuclear Information System (INIS)

    Busby, Jeremy T.; Leonard, Keith J.

    2007-01-01

    Nuclear powered spacecraft will enable missions well beyond the capabilities of current chemical, radioisotope thermal generator and solar technologies. The use of fission reactors for space applications has been considered for over 50 years, although, structural material performance has often limited the potential performance of space reactors. Space fission reactors are an extremely harsh environment for structural materials with high temperatures, high neutron fields, potential contact with liquid metals, and the need for up to 15-20 year reliability with no inspection or preventative maintenance. Many different materials have been proposed as structural materials. While all materials meet many of the requirements for space reactor service, none satisfy all of them. However, continued development and testing may resolve these issues and provide qualified materials for space fission reactors.

  3. Space shuttle booster separation motor design

    Science.gov (United States)

    Smith, G. W.; Chase, C. A.

    1976-01-01

    The separation characteristics of the space shuttle solid rocket boosters (SRBs) are introduced along with the system level requirements for the booster separation motors (BSMs). These system requirements are then translated into specific motor requirements that control the design of the BSM. Each motor component is discussed including its geometry, material selection, and fabrication process. Also discussed is the propellant selection, grain design, and performance capabilities of the motor. The upcoming test program to develop and qualify the motor is outlined.

  4. Quality Assurance for Space Instruments Built with COTS

    DEFF Research Database (Denmark)

    Guldager, Peter Buch; Thuesen, Gøsta Guldbæk; Jørgensen, John Leif

    2005-01-01

    be changed at any time and have major consequences to the components ability to survive the space environment. A safe way to protect to components, which are not Latch-Up immune, is to protect the components with a Latch-Up protection circuit. A strict control has to be established, when procuring COTS......Instruments for space can be built with COTS. However no radiation data are available for COTS, so the only way to ensure that the components can survive the space environment is to irradiate each component. Samples from each Lot have to be irradiated, because the manufac-turing process can...... component, testing and manufacturing the instrument before the instrument is qualified for space. By having a strict control with instrument built with COTS, it is possible to manufacture a reliable instrument as with Rad-Hard components....

  5. 22 CFR 19.6-2 - Qualifying court order.

    Science.gov (United States)

    2010-04-01

    ... principal's Foreign Service retirement benefit or survivor benefit. If a court directs or implies that a... Foreign Relations DEPARTMENT OF STATE PERSONNEL BENEFITS FOR SPOUSES AND FORMER SPOUSES OF PARTICIPANTS IN... the Secretary of State. A qualifying court order must— (1) Be consistent with the terms of the Act and...

  6. 26 CFR 54.4980B-3 - Qualified beneficiaries.

    Science.gov (United States)

    2010-04-01

    ... the day before the qualifying event (that is, the divorce or death) will have been by reason of D's... event, and the reason for the individual's lack of actual coverage (such as the individual's having..., the individual is covered under the group health plan by reason of another individual's election of...

  7. Development of a linear compressor for compact 2 K Gifford- McMahon cryocoolers

    International Nuclear Information System (INIS)

    Hiratsuka, Y

    2015-01-01

    Recently, a new, compact Gifford-McMahon (GM) cryocooler for cooling superconducting single photon detectors (SSPD) has been developed at Sumitomo Heavy Industries, Ltd. (SHI) [1, 2]. The objective is to reduce the total height of the expander by 33% relative to the existing RDK-101 GM expander and to reduce the total volume of the compressor unit by 50% relative to the existing CNA-11 compressor. In addition, considering the targeted cooling application, we set the design temperature targets of the first and the second stages to 1 W and 20 mW of heat load at 60 K and 2.3 K, respectively. Although optimization of the internal components is one way to miniaturize the volume of the compressor unit, major design changes are required because the volume of the adsorber and the oil separator is almost the same as the volume of the compressor capsule. Thus, one approach is to develop a non-lubricated compressor, such as a valved linear compressor. An experimental unit of a valved linear compressor was designed and built, and preliminary experiments were conducted. Under no-load condition, a low temperature of 2.19 K has been achieved. With 1 W and 14 mW heat load, the temperature is 48 K at the first stage and 2.3 K at the second stage, with an input power of about 1.2 KW. The detailed experimental results will be discussed in this paper. (paper)

  8. 75 FR 76935 - Revisions to the United States Munitions List

    Science.gov (United States)

    2010-12-10

    ... destinations and end-users depending on the significance of the item. In other words, the CCL is a more.... Step 1--Review Each USML Category and Related ECCNs Separately The USML and the CCL are too big and...

  9. 49 CFR 604.15 - Registration of qualified human service organizations.

    Science.gov (United States)

    2010-10-01

    ... low income, advanced age, or with disabilities), shall register on FTA's charter registration Web site... service organization and whether the qualified human service organization is exempt from taxation under...

  10. 77 FR 26175 - Section 42 Qualified Contract Provisions

    Science.gov (United States)

    2012-05-03

    ... indebtedness under general principles of Federal income tax law, and (3) upon the sale of the building, are... building for sale to the general public at the determined qualified contract price upon receipt of a... because of variations under State laws concerning the terms of a bona fide contract and methods for...

  11. 26 CFR 1.41-2 - Qualified research expenses.

    Science.gov (United States)

    2010-04-01

    ... Credits Against Tax § 1.41-2 Qualified research expenses. (a) Trade or business requirement—(1) In general... research and experimental expenses) are not necessarily paid or incurred in carrying on a trade or business for purposes of section 41. A research expense must relate to a particular trade or business being...

  12. "Teaching What I Learned": Exploring Students' Earth and Space Science Learning Experiences in Secondary School with a Particular Focus on Their Comprehension of the Concept of "Geologic Time"

    Science.gov (United States)

    Yoon, Sae Yeol; Peate, David W.

    2015-01-01

    According to the national survey of science education, science educators in the USA currently face many challenges such as lack of qualified secondary Earth and Space Science (ESS) teachers. Less qualified teachers may have difficulty teaching ESS because of a lack of conceptual understanding, which leads to diminished confidence in content…

  13. Cryocooler-cooled 10 T superconducting magnet; Reitoki chokurei hoshiki no 10T chodendo jishaku

    Energy Technology Data Exchange (ETDEWEB)

    Kuriyama, T.; Yamamoto, K.; Urata, M. [Toshiba Corp., Tokyo (Japan)

    1995-09-01

    A superconducting magnet totally free of such cooling agents as liquefied helium has been developed, which can be cooled by a cryocooler alone in a direct cooler cooled method, and a success was attained when a 10T magnetic field was generated in a vacancy 10cm in diameter. The value is the highest in the world realized by a system not using a cooling medium (only 7.7T attained before this). The coil comprises a coil of an NbTi superconducting lead and a coil of Nb3Sn superconducting lead, and is impregnated with epoxy resin for reduction in size. It is cooled only by heat conduction thanks to a thermally coupled 4K cooler in vacuum, and necessitates the insertion of indium between the coil and a copper made cooling board which combination is further tightened up by a stainless steel wire. Furthermore, a superconducting oxide lead has been developed, with its performance not lowered even in an intensive magnetic field, for the supply of power to the coil, and this suppresses the infiltration of conduction caused heat and the generation of Joule heat. The magnet is designed small and light with dimensions 650{times}500{times}490mm (height), and can be operated by mere manipulation of a switch. 6 refs., 6 figs.

  14. 78 FR 61987 - Corbett Water District; Notice of Preliminary Determination of a Qualifying Conduit Hydropower...

    Science.gov (United States)

    2013-10-09

    ... District; Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and Soliciting... construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower Regulatory Efficiency Act of 2013 (HREA). The Corbett Hydroelectric...

  15. 26 CFR 1.414(r)-7 - Determination of the employees of an employer's qualified separate lines of business.

    Science.gov (United States)

    2010-04-01

    ... same department, or at the same location, to the same qualified separate line of business would be an... qualified separate lines of business. 1.414(r)-7 Section 1.414(r)-7 Internal Revenue INTERNAL REVENUE...-Sharing, Stock Bonus Plans, Etc. § 1.414(r)-7 Determination of the employees of an employer's qualified...

  16. Laser transmitter for Lidar In-Space Technology Experiment

    Science.gov (United States)

    Chang, John; Cimolino, Marc; Petros, Mulugeta

    1991-01-01

    The Lidar In-Space Technology Experiment (LITE) Laser Transmitter Module (LTM) flight laser optical architecture has been space qualified by extensive testing at the system, subsystem and component level. The projected system output performance has been verified using an optically and electrically similar breadboard version of the laser. Parasitic lasing was closely examined and completely suppressed after design changes were implemented and tested. Oscillator and amplifier type heads were separately tested to 150 million shots. Critical subassemblies have undergone environmental testing to Shuttle qualification levels. A superior three color anti-reflection coating was developed and tested for use on 14 surfaces after the final amplifier.

  17. 77 FR 76941 - Defense Federal Acquisition Regulation Supplement: New Qualifying Country-Poland (DFARS Case 2012...

    Science.gov (United States)

    2012-12-31

    ... discriminatory barriers to procurements of supplies and services produced by industrial enterprises of the other....003 is amended in paragraph (10), the definition of ``qualifying country'' by adding in alphabetical... place; 0 b. In paragraph (a), the definition of ``qualifying country'', by adding, in alphabetical order...

  18. 78 FR 63176 - Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and Soliciting...

    Science.gov (United States)

    2013-10-23

    ... Preliminary Determination of a Qualifying Conduit Hydropower Facility and Soliciting Comments and Motions To... of intent to construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower Regulatory Efficiency Act of 2013 (HREA). The...

  19. The effect of qualifying language on perceptions of drug appeal, drug experience, and estimates of side-effect incidence in DTC advertising.

    Science.gov (United States)

    Davis, Joel

    2007-01-01

    This study examined how the use of qualifying language in direct-to-consumer (DTC) pharmaceutical advertising affects consumers' perceptions of drug appeal, anticipated pleasantness of drug usage, and the expected incidence of side-effect occurrence. A sample of 669 individuals participated in a 2 x 8 complete factorial design. The design manipulated the number of side effects associated with drug use and the type of qualifying language used to describe the side effects. The eight experimental qualifying language cells represented one control condition (no qualifying language), three cells where each of three types of qualifying language were presented individually, and four cells where qualifying language was combined. The results indicate that qualifying language has a profound effect on drug perceptions, especially when used in combination. Drug appeal and the anticipated drug-using experience almost always were more positive in the presence of qualifying language. Qualifying language appears to exert its influence by causing individuals to reduce their estimate of the likelihood of experiencing individual side effects. Policy implications of the research, particularly for evaluation of "fair balance" and the reporting of side effects, are presented.

  20. 34 CFR 300.18 - Highly qualified special education teachers.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Highly qualified special education teachers. 300.18... SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION ASSISTANCE TO STATES FOR THE... special education teachers. (a) Requirements for special education teachers teaching core academic...

  1. Towards Qualifiable Code Generation from a Clocked Synchronous Subset of Modelica

    Directory of Open Access Journals (Sweden)

    Bernhard Thiele

    2015-01-01

    Full Text Available So far no qualifiable automatic code generators (ACGs are available for Modelica. Hence, digital control applications can be modeled and simulated in Modelica, but require tedious additional efforts (e.g., manual reprogramming to produce qualifiable target system production code. In order to more fully leverage the potential of a model-based development (MBD process in Modelica, a qualifiable automatic code generator is needed. Typical Modelica code generation is a fairly complex process which imposes a huge development burden to any efforts of tool qualification. This work aims at mapping a Modelica subset for digital control function development to a well-understood synchronous data-flow kernel language. This kernel language allows to resort to established compilation techniques for data-flow languages which are understood enough to be accepted by certification authorities. The mapping is established by providing a translational semantics from the Modelica subset to the synchronous data-flow kernel language. However, this translation turned out to be more intricate than initially expected and has given rise to several interesting issues that require suitable design decisions regarding the mapping and the language subset.

  2. New design for a space cryo-mechanism

    Science.gov (United States)

    Durand, Gilles; Amiaux, Jérôme; Augueres, Jean-Louis; Carty, Michael; Barrière, Jean Christophe; Bouzat, Marylène; Duboué, Bruno; Lagage, Pierre Olivier; Lebeuf, Didier; Lepage, Erwan; Lemer, Isabelle; Marlaguey, Nathalie Peydrol; Poupar, Sébastien

    2008-07-01

    Based on its experience of space application instrument and its development of cryomechanism for astronomical ground based instrument VLT / VISIR, CEA Saclay is proposing a new concept of Space Cryomechanism. This design is based on VLT/VISIR cryo-mechanism design adapted to space requirements taking into account all the specification of space environment (vibrations at launch, cryogenic vacuum, materials, radiations, ...). The original concept of the design is based on the association of the key elements: a dog-clutch with Hirth teeth jaws coupled to a step-by-step space qualified cryo-motor, a bellows that allows for separation of indexing and rotating functions, and enlarged bearings design in "O" arrangement that increase robustness to vibration. The actuator has 360 steady positions that can be reached within les than a second with repeatability of 5 arcsec peak to peak. After a presentation of the details of the concept and of its benefits to robustness to space environment, the paper describes the thoroughly qualification program of the cryo-mechanism with respect to space requirements (cryo-cycling, indexing accuracy, power consumption, heat dissipation, motorisation margins, vibrations). This cryo-mechanism may be built in 3 different sizes for wheels up to 10 kg.

  3. Cryogenic Thermal Absorptance Measurements on Small-Diameter Stainless Steel Tubing

    Science.gov (United States)

    Tuttle, James; Jahromi, Amir; Canavan, Edgar; DiPirro, Michael

    2015-01-01

    The Mid Infrared Instrument (MIRI) on the James Webb Space Telescope includes a mechanical cryocooler which cools its detectors to their 6 Kelvin operating temperature. The coolant gas flows through several meters of small-diameter stainless steel tubing, which is exposed to thermal radiation from its environment. Over much of its length this tubing is gold-plated to minimize the absorption of this radiant heat. In order to confirm that the cryocooler will meet MIRI's requirements, the thermal absorptance of this tubing was measured as a function of its environment temperature. We describe the measurement technique and present the results.

  4. Registration of qualified radiation protection experts in the Netherlands

    International Nuclear Information System (INIS)

    Abrahamse, J.C.; Kops, J.A.M.M.; Vermeulen, A.M.T.I.; Zuur, C.

    2002-01-01

    In Euratom Directive 96/29 (1) the Euratom Basic Safety Standards are given. The member states of the EC have to implement this directive in their national legislation. In the Netherlands this is done in the new radiation protection legislation (Radiation Protection Decree 2002 (2)), which came into force in the first half of 2002. In this new regulation is stated that radiological activities must be done by or under supervision of a qualified radiation protection expert. With respect to the qualified expert is stated that: the qualified expert must be registered in a notified registration system; rules will be formulated with respect to the demanded qualification levels of the experts. These demands can be different for different tasks rules will be formulated for the notification of the register, the way to become registered, the costs and so on. Mid 2001 a project is started to prepare the registration system. Information was gained from and discussions took place with the important parties on the radiological playing field in the Netherlands (employers, organisations of experts and education institutes). Furthermore information is obtained from certification institutes. It was decided to accept as starting point the education levels obtained from the radiation protection education institutes, which are approved at the moment. At a later phase will be evaluated whether this system needs to be changed. In section 2 of this paper the radiation protection system in the Netherlands will be discussed in more detail. Section 2 deals with the target group and in section 3 the outlines of the registration system to be developed are discussed

  5. Environmental monitors in the Midcourse Space Experiments (MSX)

    Science.gov (United States)

    Uy, O. M.

    1993-01-01

    The Midcourse Space Experiment (MSX) is an SDIO sponsored space based sensor experiment with a full complement of optical sensors. Because of the possible deleterious effect of both molecular and particulate contamination on these sensors, a suite of environmental monitoring instruments are also being flown with the spacecraft. These instruments are the Total Pressure Sensor based on the cold-cathode gauge, a quadrupole mass spectrometer, a Bennett-type ion mass spectrometer, a cryogenic quartz crystal microbalance (QCM), four temperature-controlled QCM's, and a Xenon and Krypton Flash Lamp Experiment. These instruments have been fully space-qualified, are compact and low cost, and are possible candidate sensors for near-term planetary and atmospheric monitoring. The philosophy adopted during design and fabrication, calibration and ground testing, and modeling will be discussed .

  6. Composites Materials and Manufacturing Technologies for Space Applications

    Science.gov (United States)

    Vickers, J. H.; Tate, L. C.; Gaddis, S. W.; Neal, R. E.

    2016-01-01

    Composite materials offer significant advantages in space applications. Weight reduction is imperative for deep space systems. However, the pathway to deployment of composites alternatives is problematic. Improvements in the materials and processes are needed, and extensive testing is required to validate the performance, qualify the materials and processes, and certify components. Addressing these challenges could lead to the confident adoption of composites in space applications and provide spin-off technical capabilities for the aerospace and other industries. To address the issues associated with composites applications in space systems, NASA sponsored a Technical Interchange Meeting (TIM) entitled, "Composites Materials and Manufacturing Technologies for Space Applications," the proceedings of which are summarized in this Conference Publication. The NASA Space Technology Mission Directorate and the Game Changing Program chartered the meeting. The meeting was hosted by the National Center for Advanced Manufacturing (NCAM)-a public/private partnership between NASA, the State of Louisiana, Louisiana State University, industry, and academia, in association with the American Composites Manufacturers Association. The Louisiana Center for Manufacturing Sciences served as the coordinator for the TIM.

  7. The Role of Objects in the Constitution of Collaborative Spaces

    DEFF Research Database (Denmark)

    Balatsas Lekkas, Angelos; Yoshinaka, Yutaka

    2013-01-01

    This paper examines collaborative processes involving users and product development practitioners, in virtual co-creative spaces. Qualifications of roles are entailed in and through the mediation of objects, as they serve part and parcel of the coming-into-being of the collaboration. By focusing...... on the role played by objects in collaborative spaces, more specifically an Internet-based forum established by a medical device manufacturer for users of its products, the paper makes a threefold argument concerning the active role played by objects in collaborative processes: 1) the premises for user...... involvement in such spaces is subject to behind-the-scenes qualification processes directed at particular user configurations; 2) virtual spaces are being re-configured by users’ and practitioners’ interactions through diverse references of objects; and 3) users and practitioners qualify the content...

  8. 78 FR 62350 - FFP Qualified Hydro 14, LLC; Western Minnesota Municipal Power Agency; Notice Announcing...

    Science.gov (United States)

    2013-10-18

    .... 14491-000] FFP Qualified Hydro 14, LLC; Western Minnesota Municipal Power Agency; Notice Announcing... applications were filed by FFP Qualified Hydro 14, LLC for Project No. 13579-002 and Western Minnesota... regular business day. See 18 CFR 385.2001(a)(2) (2013). On October 21, 2013, at 10:00 a.m. (Eastern Time...

  9. 12 CFR 617.7130 - What initial disclosures must a qualified lender make to a borrower?

    Science.gov (United States)

    2010-01-01

    ... lender make to a borrower? 617.7130 Section 617.7130 Banks and Banking FARM CREDIT ADMINISTRATION FARM... must a qualified lender make to a borrower? (a) Required disclosures—in general. A qualified lender... certificates that borrowers are required to purchase are at risk and may only be retired at the discretion of...

  10. Qualified expert training: the ERPC (European Radiation Protection Course)

    International Nuclear Information System (INIS)

    Deboodt, P.; Bourguignon, M.; Juhel, T.; Lirsac, N.; Luciani, A.; Marco, M.; Schmitt-Hanning, A. M.; Van der Steen, J.

    2003-01-01

    Since 2000, a training for the qualified experts is organised by several European partners in France at Saclay near Pais. The objective of this training is to deliver the theoretical knowledge needed to be recognised as a qualified expert in radiation protection according to the European requirements. The training delivered in English, includes four independent modules; basics, occupational exposure in nuclear and industrial applications, medical exposures (patients and workers), radiation protection of the members of the public and the environment (4 or 5 weeks each). A written examination is organised at the end of each module. Lectures, practical works, exercises and visits are given by European lecturers. Students have the possibility to register in one or several module during one or several years. Participants could be students or professionals from all European countries satisfying the pre requite defined by the European board. A certificate validating the successfully passed modules will be delivered by the INSTN (National Institute of Nuclear Sciences and Technologies)

  11. Qualified expert training: the ERPC (European Radiation Protection Course)

    Energy Technology Data Exchange (ETDEWEB)

    Deboodt, P.; Bourguignon, M.; Juhel, T.; Lirsac, N.; Luciani, A.; Marco, M.; Schmitt-Hanning, A. M.; Van der Steen, J.

    2003-07-01

    Since 2000, a training for the qualified experts is organised by several European partners in France at Saclay near Pais. The objective of this training is to deliver the theoretical knowledge needed to be recognised as a qualified expert in radiation protection according to the European requirements. The training delivered in English, includes four independent modules; basics, occupational exposure in nuclear and industrial applications, medical exposures (patients and workers), radiation protection of the members of the public and the environment (4 or 5 weeks each). A written examination is organised at the end of each module. Lectures, practical works, exercises and visits are given by European lecturers. Students have the possibility to register in one or several module during one or several years. Participants could be students or professionals from all European countries satisfying the pre requite defined by the European board. A certificate validating the successfully passed modules will be delivered by the INSTN (National Institute of Nuclear Sciences and Technologies).

  12. 26 CFR 1.188-1 - Amortization of certain expenditures for qualified on-the-job training and child care facilities.

    Science.gov (United States)

    2010-04-01

    ... qualified on-the-job training and child care facilities. 1.188-1 Section 1.188-1 Internal Revenue INTERNAL... qualified on-the-job training and child care facilities. (a) Allowance of deduction—(1) In general. Under... operation of a qualified on-the-job training or child care facility or are integrally related facilities...

  13. Theoretical modeling of a gas clearance phase regulation mechanism for a pneumatically-driven split-Stirling-cycle cryocooler

    Science.gov (United States)

    Zhang, Cun-quan; Zhong, Cheng

    2015-03-01

    The concept of a new type of pneumatically-driven split-Stirling-cycle cryocooler with clearance-phase-adjustor is proposed. In this implementation, the gap between the phase-adjusting part and the cylinder of the spring chamber is used, instead of dry friction acting on the pneumatically-driven rod to control motion damping of the displacer and to adjust the phase difference between the compression piston and displacer. It has the advantages of easy damping adjustment, low cost, and simplified manufacturing and assembly. A theoretical model has been established to simulate its dynamic performance. The linear compressor is modeled under adiabatic conditions, and the displacement of the compression piston is experimentally rectified. The working characteristics of the compressor motor and the principal losses of cooling, including regenerator inefficiency loss, solid conduction loss, shuttle loss, pump loss and radiation loss, are taken into account. The displacer motion was modeled as a single-degree-of-freedom (SDOF) forced system. A set of governing equations can be solved numerically to simulate the cooler's performance. The simulation is useful for understanding the physical processes occurring in the cooler and for predicting the cooler's performance.

  14. Nursing educator perspectives of overseas qualified nurses' intercultural clinical communication: barriers, enablers and engagement strategies.

    Science.gov (United States)

    Philip, Susan; Manias, Elizabeth; Woodward-Kron, Robyn

    2015-09-01

    To understand the intercultural communication experiences and associated communication training needs of overseas qualified nurses in the Australian healthcare system from the unique perspectives of nurse educators teaching in accredited bridging programmes. Overseas qualified nurses are an integral part of the nursing workforce in migration destination countries. Communication training needs are more complex when there are cultural, ethnic and language differences between nurses, other health professionals and patients. A qualitative, exploratory research design using semi-structured interviews. All (nine) organisations involved in conducting the Australian Health Practitioner Regulation Agency approved preregistration bridging programmes for overseas qualified nurses within the state of Victoria, Australia, were involved in the study. Participants were 12 nurse educators employed in these organisations. Thematic analysis was undertaken. Three macro themes emerged about the overseas qualified nurses' intercultural communication: (1) pre-existing barriers and enablers to intercultural communication, for example, nurses' reluctance to engage in communicative strategies that build rapport with patients, (2) transitional behaviours and impact on communication, including maintenance of perceived cultural hierarchies between health professionals and (3) development of communicative competence, including expanding one's repertoire of conversational gambits. The findings point to the domains and causes of communication challenges facing overseas qualified nurses in new healthcare settings as well as strategies that the nurse educators and nurses can adopt. Communication cannot be merely regarded as a skill that can be taught in a didactic programme. Comprehensive understanding is needed about the sociocultural dimensions of these nurses' orientation, which can impact on how they communicate in their new healthcare settings. The findings can act as triggers for discussion

  15. Assessment of demand for and supply of qualified manpower for the nuclear industry

    International Nuclear Information System (INIS)

    Morelle, J.

    1993-01-01

    The OECD Nuclear Energy Agency recently published a study which presents the results of a pioneering survey of the demand for and the supply of qualified manpower in various sectors of the nuclear industry (including medicine), and in the related areas of regulation and education in 12 OECD countries. The current manpower situation is presented and the future demand is reviewed. Present and future activities of OECD countries to ensure a balance between supply and demand of qualified manpower are discussed

  16. 26 CFR 1.221-2 - Deduction for interest due and paid on qualified education loans before January 1, 2002.

    Science.gov (United States)

    2010-04-01

    ... Individuals § 1.221-2 Deduction for interest due and paid on qualified education loans before January 1, 2002... interest due and paid by the taxpayer during the taxable year on a qualified education loan. The deduction is allowed only with respect to interest due and paid on a qualified education loan during the first...

  17. Virginia Tech team qualifies as DARPA Urban Challenge semi-finalist

    OpenAIRE

    Crumbley, Liz

    2007-01-01

    "VictorTango," a team of Virginia Tech engineering and geography students, will travel to Victorville, Calif., for the national qualifying rounds of the Urban Challenge autonomous vehicle competition, sponsored by the Defense Advanced Research Projects Agency (DARPA).

  18. Space and commodity-based society

    Directory of Open Access Journals (Sweden)

    Gvozden Vladimir

    2015-01-01

    Full Text Available The space is privileged in the commodity-based society. It is well known that the economic space in the 19th and 20th centuries rapidly managed to subordinate all other areas 'conveying and instilling in them their own meanings and goals' (G. Milatović. A new form of space that qualifies commodity society was created, marked by dualities: openness-closeness, private-public, sameness-difference. This paper is an attempt to criticize the usual analysis of the categories of commodity-space, linked to the ambivalent role of the state as a guarantor of the functioning of the commodity-based society, as well as its controlling instance. The increasing delocalisation of the political changes the nature of the space in the commodity-based society. Privileged areas are produced that create an illusion of protection of consumers (shopping malls, gated communities, theme parks, video surveillance, while at the same time social differentiation and identification are produced through the symbolic order of commodities and a sense of inclusion or exclusion from that order. At the same time, the examples of tourism and selling places demonstrate that such a commodity-space unusually easy reconciles sameness and difference. It entails uniformity to help achieve the fluctuation of goods, while insisting on the local as different, especially in terms of the role of particularity in the global trade.

  19. Spatial factors as contextual qualifiers of information seeking

    Directory of Open Access Journals (Sweden)

    R. Savolainen

    2006-01-01

    Full Text Available Introduction. This paper investigates the ways in which spatial factors have been approached in information seeking studies. The main attention was focused on studies discussing information seeking on the level of source selection and use. Method. Conceptual analysis of about 100 articles and books thematizing spatial issues of information seeking. Due to research economy, the main attention was paid to studies on everyday life information seeking. Results. Three major viewpoints were identified with regard to the degree of objectivity of spatial factors. The objectifying approach conceives of spatial factors as external and entity-like qualifiers that primarly constrain information seeking. The realistic-pragmatic approach emphasizes the ways in which the availabilty of information sources in different places such as daily work environments orient information seeking. The perspectivist approach focuses on how people subjectively assess the significance of various sources by means of spatial constructs such as information horizons. Conclusion. Spatial factors are centrally important contextual qualifiers of information seeking. There is a need to further explore the potential of the above viewpoints by relating the spatial and temporal factors of information seeking.

  20. Characterization of a low frequency magnetic noise from a two stage pulse tube cryocooler

    International Nuclear Information System (INIS)

    Eshraghi, Mohamad Javad; Sasada, Ichiro; Kim, Jin Mok; Lee, Yong Ho

    2008-01-01

    Magnetic noise of a two stage pulse tube cryocooler(PT) has been measured by a fundamental mode orthogonal fluxgate magnetometer and by a LTS SQUID gradiometer. The magnetometer was installed in a Dewar made of aluminum at 12 cm apart from a section containing magnetic regenerative materials of the PT. The magnetic noise shows a clear peak at 1.8 Hz which is the fundamental frequency of the He gas pumping rate. The 1.8 Hz magnetic noise took a peak, during the cooling process, when the cold stage temperature was at (or close to) 12 K, which resembles the variation of the temperature of the second cold stage of 1.8 Hz. Hence we attributed the main source of this magnetic noise to the temperature dependency of magnetic susceptibility of magnetic regenerative materials such as Er3Ni and HoCu2 used at the second stage. We pointed out that the superconducting magnetic shield by lead sheets reduced the interfering magnetic noise generated from this part. With this scheme, the magnetic noise amplitude measured with the first order gradiometer DROS, mounted in the vicinity of the magnetic regenerator, when the noise amplitude is minimum, which could be found from the fluxgate measurement results, was less than 500 pT peak to peak. Whereas without lead shielding the noise level was higher than the dynamic range of SQUID instrumentations which is around ±10nT. (author)

  1. Multiobjective optimizations of a novel cryocooled dc gun based ultrafast electron diffraction beam line

    Directory of Open Access Journals (Sweden)

    Colwyn Gulliford

    2016-09-01

    Full Text Available We present the results of multiobjective genetic algorithm optimizations of a single-shot ultrafast electron diffraction beam line utilizing a 225 kV dc gun with a novel cryocooled photocathode system and buncher cavity. Optimizations of the transverse projected emittance as a function of bunch charge are presented and discussed in terms of the scaling laws derived in the charge saturation limit. Additionally, optimization of the transverse coherence length as a function of final rms bunch length at the sample location have been performed for three different sample radii: 50, 100, and 200  μm, for two final bunch charges: 10^{5} electrons (16 fC and 10^{6} electrons (160 fC. Example optimal solutions are analyzed, and the effects of disordered induced heating estimated. In particular, a relative coherence length of L_{c,x}/σ_{x}=0.27  nm/μm was obtained for a final bunch charge of 10^{5} electrons and final bunch length of σ_{t}≈100  fs. For a final charge of 10^{6} electrons the cryogun produces L_{c,x}/σ_{x}≈0.1  nm/μm for σ_{t}≈100–200  fs and σ_{x}≥50  μm. These results demonstrate the viability of using genetic algorithms in the design and operation of ultrafast electron diffraction beam lines.

  2. 78 FR 66355 - Pleasant Grove City, UT; Notice of Preliminary Determination of a Qualifying Conduit Hydropower...

    Science.gov (United States)

    2013-11-05

    ... City, UT; Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and... Grove City, Utah (Pleasant Grove) filed a notice of intent to construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower...

  3. 78 FR 53752 - City of Sandpoint, Idaho; Notice of Preliminary Determination of a Qualifying Conduit Hydropower...

    Science.gov (United States)

    2013-08-30

    ... Sandpoint, Idaho; Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and... intent to construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower Regulatory Efficiency Act of 2013 (HREA). The Little...

  4. 78 FR 61985 - City of Astoria, Oregon; Notice of Preliminary Determination of a Qualifying Conduit Hydropower...

    Science.gov (United States)

    2013-10-09

    ..., Oregon; Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and Soliciting... of intent to construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower Regulatory Efficiency Act of 2013 (HREA). The...

  5. Using neutrosophic graph cut segmentation algorithm for qualified rendering image selection in thyroid elastography video.

    Science.gov (United States)

    Guo, Yanhui; Jiang, Shuang-Quan; Sun, Baiqing; Siuly, Siuly; Şengür, Abdulkadir; Tian, Jia-Wei

    2017-12-01

    Recently, elastography has become very popular in clinical investigation for thyroid cancer detection and diagnosis. In elastogram, the stress results of the thyroid are displayed using pseudo colors. Due to variation of the rendering results in different frames, it is difficult for radiologists to manually select the qualified frame image quickly and efficiently. The purpose of this study is to find the qualified rendering result in the thyroid elastogram. This paper employs an efficient thyroid ultrasound image segmentation algorithm based on neutrosophic graph cut to find the qualified rendering images. Firstly, a thyroid ultrasound image is mapped into neutrosophic set, and an indeterminacy filter is constructed to reduce the indeterminacy of the spatial and intensity information in the image. A graph is defined on the image and the weight for each pixel is represented using the value after indeterminacy filtering. The segmentation results are obtained using a maximum-flow algorithm on the graph. Then the anatomic structure is identified in thyroid ultrasound image. Finally the rendering colors on these anatomic regions are extracted and validated to find the frames which satisfy the selection criteria. To test the performance of the proposed method, a thyroid elastogram dataset is built and totally 33 cases were collected. An experienced radiologist manually evaluates the selection results of the proposed method. Experimental results demonstrate that the proposed method finds the qualified rendering frame with 100% accuracy. The proposed scheme assists the radiologists to diagnose the thyroid diseases using the qualified rendering images.

  6. Investigation of a high frequency pulse tube cryocooler driven by a standing wave thermoacoustic engine

    International Nuclear Information System (INIS)

    Boroujerdi, A.A.; Ziabasharhagh, M.

    2014-01-01

    Highlights: • A nonlinear numerical model of a high frequency TADPTC has been developed. • The finite volume method has been used for discretization of governing equations. • The self-excitation process has been simulated very well. • The effects of APAT on the performance of the device have been investigated. • Lagrangian approach has been used to trace the thermodynamic cycle of gas parcels. - Abstract: In this work, a typical thermoacoustically driven pulse tube cooler as a no-moving part device has been investigated by a numerical method. A standing wave thermoacoustic engine as a prime mover in coupled with an inertance tube pulse tube cryocooler has been modeled. Nonlinear equations of unsteady one-dimensional compressible flow have been solved by the finite volume method. The model presents an important step towards the development of nonlinear simulation tools for the high amplitude thermoacoustic systems that are needed for practical use. The results of the computations show that the self-excited oscillations are well accompanied by the increasing of the pressure amplitude. The necessity of implementation of a nonlinear model to investigate such devices has been proven. The effect of APAT length as an amplifier coupler on the performance of the cooler has been investigated. Furthermore, by using Lagrangian approach, thermodynamic cycle of gas parcels has been attained

  7. 9 CFR 77.36 - Interstate movement from qualified herds.

    Science.gov (United States)

    2010-01-01

    ... date of movement. If a group of captive cervids from a qualified herd is being moved interstate... unclassified herd. (4) Captive cervids being moved interstate for the purpose of exhibition only may be moved... being moved directly from a classified herd, the captive cervid must be isolated from all other animals...

  8. 24 CFR 266.100 - Qualified housing finance agency (HFA).

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Qualified housing finance agency (HFA). 266.100 Section 266.100 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT MORTGAGE...

  9. 12 CFR 617.7315 - What records must the qualified lender maintain on behalf of the CRC?

    Science.gov (United States)

    2010-01-01

    ... on behalf of the CRC? 617.7315 Section 617.7315 Banks and Banking FARM CREDIT ADMINISTRATION FARM... must the qualified lender maintain on behalf of the CRC? A qualified lender must maintain a complete file of all requests for CRC reviews, including participation in state mediation programs, the minutes...

  10. 78 FR 56872 - City of Barre, Vermont; Notice of Preliminary Determination of a Qualifying Conduit Hydropower...

    Science.gov (United States)

    2013-09-16

    ..., Vermont; Notice of Preliminary Determination of a Qualifying Conduit Hydropower Facility and Soliciting... construct a qualifying conduit hydropower facility, pursuant to section 30 of the Federal Power Act, as amended by section 4 of the Hydropower Regulatory Efficiency Act of 2013 (HREA). The Nelson Street 17 kW...

  11. Dynamic characterization of satellite assembly for responsive space applications

    International Nuclear Information System (INIS)

    Mascarenas, David; Macknelly, David; Mullins, Josh; Wiest, Heather; Park, Gyuhae

    2013-01-01

    The rapid deployment of satellites for responsive space surveillance applications is hindered by the need to flight-qualify their components and the resulting mechanical assembly. Conventional methods for qualification testing of satellite components are costly and time consuming. Furthermore, full-scale vehicles must be subjected to simulated launch loads during testing, and this harsh testing environment increases the risk of damage to satellite components during qualification. This work focuses on replacing this potentially destructive testing procedure with a non-destructive structural health monitoring (SHM)-based technique while maintaining the same level of confidence in the testing procedure's ability to qualify the satellite for flight. We focus on assessing the performance of SHM techniques to replace the high-cost qualification procedure and to localize faults introduced by improper assembly. The goal of this work is to create a dual-use system that can both assist in the process of qualifying the satellite for launch, as well as provide continuous structural integrity monitoring during manufacture, transport, launch and deployment. SHM techniques were applied on a small-scale structure representative of a responsive satellite. The test structure consisted of an extruded aluminum space-frame covered with aluminum shear plates assembled using bolted joints. Multiple piezoelectric transducers were bonded to the test structure and acted as combined actuators and sensors. Piezoelectric active-sensing based techniques, including measurements of low-frequency global frequency response functions and high-frequency wave propagation techniques, were employed. Using these methods in conjunction with finite element modeling, the dynamic properties of the test structure were established and areas of potential damage could be identified and localized. A procedure for guiding the effective placement of the sensors and actuators is also outlined. (paper)

  12. A longitudinal, mixed methods investigation of newly qualified nurses' workplace stressors and stress experiences during transition.

    Science.gov (United States)

    Halpin, Yvonne; Terry, Louise M; Curzio, Joan

    2017-11-01

    To investigate transition in newly qualified nurses through an exploration of their stressors and stress experiences during their first 12 months postqualifying. Globally, thousands of new nurses qualify annually. They are crucial for the profession and healthcare service delivery. Work-related stress has multiple serious consequences, yet there is a lack of robust, empirical evidence that directly analyses newly qualified nurses and the stress they feel and experience in the workplace. Understanding what causes newly qualified nurses' stress is vital to retaining and nurturing this vital component of the workforce. Longitudinal, explanatory sequential mixed methods, cohort study. At the point of qualification (n = 288), 6 months postqualifying (n = 107) and 12 months postqualifying (n = 86), newly qualified nurses completed the Nursing Stress Scale, with 14 completing a one-to-one interview at 12 months postqualifying. Data were collected from 2010 - 2012. Inferential statistics, "thematic analysis" and "side-by-side comparisons in a discussion" were used for analysis. Workload was consistently the highest reported stressor with inadequate staffing and managing multiple role demands given as explanations. Incivility within the workplace was a noted stressor. Conversely, being part of "a good team" provided a civil, supportive, facilitative work environment. Entering nurse education with previous healthcare experience had a mediating effect on the reported frequency of stressors. Newly qualified nurses encounter multiple work-related stressors over their first 12 months postqualifying, which are intrinsically entwined with their transition. Employing organizations need to be more proactive in managing their workload and addressing workplace incivility. © 2017 John Wiley & Sons Ltd.

  13. 31 CFR Appendix A to Part 500 - Qualifying International Institutions

    Science.gov (United States)

    2010-07-01

    ... Pt. 500, App. A Appendix A to Part 500—Qualifying International Institutions Asian Development Bank (ADB) Food and Agricultural Organization (FAO) International Bank for Reconstruction and Development (IBRD, the “World Bank”) International Civil Aviation Organization (ICAO) International Development...

  14. 78 FR 45017 - Amendment to the International Traffic in Arms Regulations: Revision of U.S. Munitions List...

    Science.gov (United States)

    2013-07-25

    ... the defense articles on the USML that are controlled by the Bureau of Alcohol, Tobacco, Firearms and...) Underwater single acoustic sensor system that distinguishes tonals and locates the origin of the sound; (iii... incorporating revision of USML Category XI]. (8) Unattended ground sensor (UGS) systems or equipment having all...

  15. 77 FR 23373 - Small Business Investment Companies-Energy Saving Qualified Investments

    Science.gov (United States)

    2012-04-19

    ... appropriate for inclusion in the definition. Furthermore, if a Small Business generates revenues solely from... definition of Energy Saving Qualified Investment by adding a presumption that a Small Business will be...

  16. A missing piece of the workforce puzzle. The experiences of internationally qualified nurses in New Zealand: a literature review.

    Science.gov (United States)

    Jenkins, Brittany Lauren; Huntington, Annette

    2015-01-01

    To analyse the literature regarding the context and experiences of internationally qualified registered nurses, particularly Filipino and Indian nurses, who have transitioned to New Zealand. Internationally qualified nurses are a significant proportion of the nursing workforce in many developed countries including New Zealand. This is increasingly important as populations age, escalating demand for nurses. Understanding the internationally qualified nurse experience is required as this could influence migration in a competitive labour market. Examination of peer-reviewed research, policy and discussion documents, and technical reports. A systematic literature search sought articles published between 2001 and 2014 using Google Scholar, CINAHL, and Medline. Articles were critically appraised for relevance, transferability, and methodological rigour. Fifty-one articles met inclusion criteria and demonstrate internationally qualified nurses face significant challenges transitioning into New Zealand. The internationally qualified nurse experience of transitioning into a new country is little researched and requires further investigation.

  17. Large Propellant Tank Cryo-Cooler (LPTC)

    Data.gov (United States)

    National Aeronautics and Space Administration — In rocket test and launch facilities, cryogenic propellants stored in tanks boils off due to heat leakage, with the following impacts:Ø   Waste, propellants boil off...

  18. Statistically qualified neuro-analytic failure detection method and system

    Science.gov (United States)

    Vilim, Richard B.; Garcia, Humberto E.; Chen, Frederick W.

    2002-03-02

    An apparatus and method for monitoring a process involve development and application of a statistically qualified neuro-analytic (SQNA) model to accurately and reliably identify process change. The development of the SQNA model is accomplished in two stages: deterministic model adaption and stochastic model modification of the deterministic model adaptation. Deterministic model adaption involves formulating an analytic model of the process representing known process characteristics, augmenting the analytic model with a neural network that captures unknown process characteristics, and training the resulting neuro-analytic model by adjusting the neural network weights according to a unique scaled equation error minimization technique. Stochastic model modification involves qualifying any remaining uncertainty in the trained neuro-analytic model by formulating a likelihood function, given an error propagation equation, for computing the probability that the neuro-analytic model generates measured process output. Preferably, the developed SQNA model is validated using known sequential probability ratio tests and applied to the process as an on-line monitoring system. Illustrative of the method and apparatus, the method is applied to a peristaltic pump system.

  19. Federally qualified health center dental clinics: financial information.

    Science.gov (United States)

    Bailit, Howard L; Devitto, Judy; Myne-Joslin, Ronnie; Beazoglou, Tryfon; McGowan, Taegan

    2013-01-01

    Federally Qualified Health Center (FQHC) dental clinics are a major component of the dental safety net system, providing care to 3.75 million patients annually. This study describes the financial and clinical operations of a sample of FQHCs. In cooperation with the National Network for Oral Health Access, FQHC dental clinics that could provide 12 months of electronic dental record information were asked to participate in the study. Based on data from 28 dental clinics (14 FQHCs), 50 percent of patients were under 21 years of age. The primary payers were Medicaid (72.4 percent) and sliding-scale/self-pay patients (17.5 percent). Sites averaged 3.1 operatories, 0.66 dental hygienists, and 1.9 other staff per dentist. Annually, each FTE dentist and hygienist provided 2,801 and 2,073 patient visits, respectively. Eighty percent of services were diagnostic, preventive, and restorative. Patient care accounted for 82 percent of revenues, and personnel (64.2 percent) and central administration (13.4 percent) accounted for most expenses. Based on a small convenience sample of FQHC dental clinics, this study presents descriptive data on their clinical and financial operations. Compared with data from the UDS (Uniform Data System) report, study FQHCs were larger in terms of space, staff, and patients served. However, there was substantial variation among clinics for almost all measures. As the number and size of FQHC dental clinics increase, the Health Resources and Services Administration needs to provide them access to comparative data that they can use to benchmark their operations. © 2013 American Association of Public Health Dentistry.

  20. Exploring the Unknown: Selected Documents in the History of the U.S. Civil Space Program. Volume 4; Accessing Space

    Science.gov (United States)

    Logsdon, John M. (Editor); Williamson, Ray A. (Editor); Launius, Roger D. (Editor); Acker, Russell J. (Editor); Garber, Stephen J. (Editor); Friedman, Jonathan L. (Editor)

    1999-01-01

    The documents selected for inclusion in this volume are presented in four major chapters, each covering a particular aspect of access to space and the manner in which it has developed over time. These chapters focus on the evolution toward the giant Saturn V rocket, the development of the Space Shuttle, space transportation commercialization, and future space transportation possibilities. Each chapter in this volume is introduced by an overview essay, prepared by individuals who are particularly well qualified to write on the topic. In the main, these essays are intended to introduce and complement the documents in the chapter and to place them, for the most part, in a chronological and substantive context. Each essay contains references to the documents in the chapter it introduces, and many also contain references to documents in other chapters of the collection. These introductory essays are the responsibility of their individual authors, and the views and conclusions contained therein do not necessarily represent the opinions of either George Washington University or NASA.

  1. 26 CFR 20.2039-2 - Annuities under “qualified plans” and section 403(b) annuity contracts.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Annuities under âqualified plansâ and section 403(b) annuity contracts. 20.2039-2 Section 20.2039-2 Internal Revenue INTERNAL REVENUE SERVICE... AUGUST 16, 1954 Gross Estate § 20.2039-2 Annuities under “qualified plans” and section 403(b) annuity...

  2. 49 CFR 213.305 - Designation of qualified individuals; general qualifications.

    Science.gov (United States)

    2010-10-01

    ... college level engineering program, supplemented by special on the job training emphasizing the techniques... engineering program, supplemented by special on the job training emphasizing the techniques to be employed in... 49 Transportation 4 2010-10-01 2010-10-01 false Designation of qualified individuals; general...

  3. A Stirling Idea

    Science.gov (United States)

    1998-01-01

    Stirling Technology Company developed the components for its BeCOOL line of Cryocoolers with the help of a series of NASA SBIRs (Small Business Innovative Research), through Goddard Space Flight Center and Marshall Space Flight Center. Features include a hermetically sealed design, compact size, and silent operation. The company has already placed several units with commercial customers for computer applications and laboratory use.

  4. Relationships between study habits, burnout, and general surgery resident performance on the American Board of Surgery In-Training Examination.

    Science.gov (United States)

    Smeds, Matthew R; Thrush, Carol R; McDaniel, Faith K; Gill, Roop; Kimbrough, Mary K; Shames, Brian D; Sussman, Jeffrey J; Galante, Joseph M; Wittgen, Catherine M; Ansari, Parswa; Allen, Steven R; Nussbaum, Michael S; Hess, Donald T; Knight, David C; Bentley, Frederick R

    2017-09-01

    The American Board of Surgery In-Training Examination (ABSITE) is used by programs to evaluate the knowledge and readiness of trainees to sit for the general surgery qualifying examination. It is often used as a tool for resident promotion and may be used by fellowship programs to evaluate candidates. Burnout has been associated with job performance and satisfaction; however, its presence and effects on surgical trainees' performance are not well studied. We sought to understand factors including burnout and study habits that may contribute to performance on the ABSITE examination. Anonymous electronic surveys were distributed to all residents at 10 surgical residency programs (n = 326). Questions included demographics as well as study habits, career interests, residency characteristics, and burnout scores using the Oldenburg Burnout Inventory, which assesses burnout because of both exhaustion and disengagement. These surveys were then linked to the individual's 2016 ABSITE and United States Medical Licensing Examination (USMLE) step 1 and 2 scores provided by the programs to determine factors associated with successful ABSITE performance. In total, 48% (n = 157) of the residents completed the survey. Of those completing the survey, 48 (31%) scored in the highest ABSITE quartile (≥75th percentile) and 109 (69%) scored less than the 75th percentile. In univariate analyses, those in the highest ABSITE quartile had significantly higher USMLE step 1 and step 2 scores (P shop compared with at home; P < 0.04), and used active rather than passive study strategies (P < 0.04). Gender, marital status, having children, and debt burden had no correlation with examination success. Backward stepwise multiple regression analysis identified the following independent predictors of ABSITE scores: study location (P < 0.0001), frequency of reading (P = 0.0001), Oldenburg Burnout Inventory exhaustion (P = 0.02), and USMLE step 1 and 2 scores (P = 0.007 and 0

  5. Regulatory guides for qualifying the calculation methodology of Furnas by CNEN

    International Nuclear Information System (INIS)

    1987-10-01

    Regulatory guides are presented which will be used for qualifying the calculation methodology of FURNAS by CNEN, in the areas of Neutronics, Thermohydraulics, Accident Analysis and Fuel Rod Performance, as applied to Angra 1 NPP. (Author) [pt

  6. United States Medical Licensing Examination and American Board of Pediatrics Certification Examination Results: Does the Residency Program Contribute to Trainee Achievement.

    Science.gov (United States)

    Welch, Thomas R; Olson, Brad G; Nelsen, Elizabeth; Beck Dallaghan, Gary L; Kennedy, Gloria A; Botash, Ann

    2017-09-01

    To determine whether training site or prior examinee performance on the US Medical Licensing Examination (USMLE) step 1 and step 2 might predict pass rates on the American Board of Pediatrics (ABP) certifying examination. Data from graduates of pediatric residency programs completing the ABP certifying examination between 2009 and 2013 were obtained. For each, results of the initial ABP certifying examination were obtained, as well as results on National Board of Medical Examiners (NBME) step 1 and step 2 examinations. Hierarchical linear modeling was used to nest first-time ABP results within training programs to isolate program contribution to ABP results while controlling for USMLE step 1 and step 2 scores. Stepwise linear regression was then used to determine which of these examinations was a better predictor of ABP results. A total of 1110 graduates of 15 programs had complete testing results and were subject to analysis. Mean ABP scores for these programs ranged from 186.13 to 214.32. The hierarchical linear model suggested that the interaction of step 1 and 2 scores predicted ABP performance (F[1,1007.70] = 6.44, P = .011). By conducting a multilevel model by training program, both USMLE step examinations predicted first-time ABP results (b = .002, t = 2.54, P = .011). Linear regression analyses indicated that step 2 results were a better predictor of ABP performance than step 1 or a combination of the two USMLE scores. Performance on the USMLE examinations, especially step 2, predicts performance on the ABP certifying examination. The contribution of training site to ABP performance was statistically significant, though contributed modestly to the effect compared with prior USMLE scores. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. 12 CFR 24.6 - Examples of qualifying public welfare investments.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Examples of qualifying public welfare investments. 24.6 Section 24.6 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY... finance small businesses or small farms, including minority- and women-owned small businesses or small...

  8. 77 FR 9846 - Source of Income From Qualified Fails Charges

    Science.gov (United States)

    2012-02-21

    ... temporary regulations noted that no trading practice existed at that time for fails charges on securities other than Treasuries, but that if a fails charge trading practice pertaining to other securities was... sources within the United States, and the income from the qualified fails charge is treated as effectively...

  9. Professional paradox: identity formation in qualified doctors pursuing further training.

    Science.gov (United States)

    Chan, Mercedes; Pratt, Dan; Poole, Gary; Sidhu, Ravi

    2018-03-01

    Many newly qualified specialists and subspecialists pursue additional training. Although their motivations are many, the pursuit of further training as an alternative to unemployment is an emerging trend. Paradoxically, doctors continue as trainees with a consultant's credentials, and without the guarantee of eventual employment. This study explores seven doctors' experiences, the effects of further training on their professional identity formation (PIF), and how these effects are reconciled on a personal and professional level. This phenomenological study involved interviews with seven qualified Canadian specialists (three were female) who pursued additional training in response to a lack of available positions in their respective specialties. Template analysis generated theoretical constructs of influences on their PIF, and characteristics of their lived experiences. Four themes shaped PIF: setting and context; language and communication; responsibilities and privileges; and participants' visions of their future selves. Professional identity formation (PIF) continued to develop in further training, but was inconsistently affirmed by participants' communities of practice. Four major themes characterised training experiences: prescription; managing multiple masters; limiting access to others and community ties; and constantly questioning the value of extra training. Qualified doctors traverse professional paradoxes as they seek further education with no guarantee of employment and provide consultant-level care as 'trainees'. An identity dissonance emerges that may continue until a clear identity is prescribed for them. Although disruptive to these doctors' PIF and personal and professional lives, the long-term effects of additional training are unknown. Its utility and influence on securing employment and future job satisfaction are areas for further research. © 2017 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

  10. Qualifying cogeneration in Texas and Louisiana

    International Nuclear Information System (INIS)

    Jenkins, S.C.; Cabe, R.; Stauffaeher, J.J.

    1992-01-01

    This paper reports that cogeneration of electricity and useful thermal energy by industrials along the Gulf Coast grew significantly more rapidly than in other parts of the country during and immediately following World War II as a result of the concentration of chemical and plastics processing facilities there. In 1982, Texas passed its version of PURPA, the Public Utility Regulatory Act (PURA) and designated those non-utility generators from which public utilities must purchase electricity as Qualifying Cogenerators. In 1991, there were nearly 7,500 MW of QF power generated for inside-the-fence use or firm capacity sale to utilities, with the two largest utilities in Texas purchasing over half that amount

  11. Developmental Considerations on the Free-piston Stirling Power Convertor for Use in Space

    Science.gov (United States)

    Schreiber, Jeffrey G.

    2007-01-01

    Free-piston Stirling power conversion has been considered a candidate for radioisotope power systems for space for more than a decade. Prior to the free-piston Stirling architecture, systems were designed with kinematic Stirling engines with rotary alternators to convert heat to electricity. These systems were proposed with lightly loaded linkages to achieve the necessary life. When the free-piston configuration was initially proposed, it was thought to be attractive due to the relatively high conversion efficiency, acceptable mass, and the potential for long life and high reliability. These features have consistently been recognized by teams that have studied technology options for radioisotope power systems. Since free-piston Stirling power conversion was first considered for space power applications, there have been major advances in three general areas of development: demonstration of life and reliability, the success achieved by Stirling cryocoolers in flight, and the overall developmental maturity of the technology for both flight and terrestrial applications. Based on these advances, free-piston Stirling convertors are currently being developed for a number of terrestrial applications. They commonly operate with the power, efficiency, life, and reliability as intended, and much of the development now centers on system integration. This paper will summarize the accomplishments of free-piston Stirling power conversion technology over the past decade, review the status, and discuss the challenges that remain.

  12. Pedagogical characteristics of the systems for assessing the technical and tactical skills of qualified volleyball players

    Directory of Open Access Journals (Sweden)

    Мykhailo Oliinyk

    2017-12-01

    Full Text Available Purpose: on the basis of the analysis of the special literature and their own experimental studies, to determine the characteristics of the systems for assessing the technical and tactical skills of qualified volleyball players. Material & Methods: study was conducted on the basis of the material of the national team of Zaporozhye State Medical University on volleyball. Analysis and generalization of the data of scientific and methodical literature are used; registration, analysis and interpretation of indicators of technical and tactical actions of qualified volleyball players in training and competitive processes; pedagogical observations; algorithms for calculating the quantitative and qualitative indicators of technical and tactical skill in volleyball; methods of mathematical statistics. Results: data on the existence of a strong statistical relationship between the systems of assessment of technical and tactical skills of qualified volleyball players, taking into account the specificity of the game role. Conclusion: shows the specifics of the application of various systems for assessing the technical and tactical skills of qualified volleyball players, taking into account the factors of the game role, noted the methodological features of special analysis and interpretation of indicators of technical and tactical actions in the adversarial process.

  13. Changes in sickness absenteeism following the introduction of a qualifying day for sickness benefit--findings from Sweden Post

    DEFF Research Database (Denmark)

    Voss, M; Floderus, B; Diderichsen, F

    2001-01-01

    AIMS: In 1993, a qualifying day without sickness benefit was introduced to the Swedish sickness benefit system. The aim of the present study is to investigate sickness absenteeism before and after the introduction of the qualifying day, in the light of conditions inside and outside working life....... METHODS: The study was based on 1,952 female and 2,229 male employees of Sweden Post. Sickness absence was measured by sickness incidence one year before and one year after the introduction of the qualifying day (sick-leave events/person days at risk). Information about explanatory factors was collected...

  14. 26 CFR 1.1275-6 - Integration of qualifying debt instruments.

    Science.gov (United States)

    2010-04-01

    ... § 1.483-4 or § 1.1275-4(c) (certain contingent payment debt instruments issued for nonpublicly traded... the qualifying debt instrument. A financial instrument that hedges currency risk is not a § 1.1275-6... denominated in pounds, the swap hedges only interest rate risk, not currency risk. Therefore, the transaction...

  15. Implementing CDIO Approach in preparing engineers for Space Industry

    Directory of Open Access Journals (Sweden)

    Daneykin Yury

    2017-01-01

    Full Text Available The necessity to train highly qualified specialists leads to the development of the trajectory that can allow training specialists for the space industry. Several steps have been undertaken to reach this purpose. First, the University founded the Space Instrument Design Center that promotes a wide range of initiatives in the sphere of educating specialists, retraining specialists, carrying out research and collaborating with profiled enterprises. The University introduced Elite Engineering Education system to attract talented specialist and help them to follow individual trajectory to train unique specialist. The paper discusses the targets necessary for achievement to train specialists. Moreover, the paper presents the compliance of the attempts with the CDIO Approach, which is widely used in leading universities to improve engineering programs.

  16. SpaceWire Driver Software for Special DSPs

    Science.gov (United States)

    Clark, Douglas; Lux, James; Nishimoto, Kouji; Lang, Minh

    2003-01-01

    A computer program provides a high-level C-language interface to electronics circuitry that controls a SpaceWire interface in a system based on a space qualified version of the ADSP-21020 digital signal processor (DSP). SpaceWire is a spacecraft-oriented standard for packet-switching data-communication networks that comprise nodes connected through bidirectional digital serial links that utilize low-voltage differential signaling (LVDS). The software is tailored to the SMCS-332 application-specific integrated circuit (ASIC) (also available as the TSS901E), which provides three highspeed (150 Mbps) serial point-to-point links compliant with the proposed Institute of Electrical and Electronics Engineers (IEEE) Standard 1355.2 and equivalent European Space Agency (ESA) Standard ECSS-E-50-12. In the specific application of this software, the SpaceWire ASIC was combined with the DSP processor, memory, and control logic in a Multi-Chip Module DSP (MCM-DSP). The software is a collection of low-level driver routines that provide a simple message-passing application programming interface (API) for software running on the DSP. Routines are provided for interrupt-driven access to the two styles of interface provided by the SMCS: (1) the "word at a time" conventional host interface (HOCI); and (2) a higher performance "dual port memory" style interface (COMI).

  17. HIGHLY QUALIFIED WORKING FORCE – KEY ELEMENT OF INNOVATIVE DEVELOPMENT MODEL

    Directory of Open Access Journals (Sweden)

    M. Avksientiev

    2014-12-01

    Full Text Available Highly qualified working force is a central element of intensive development model in modern society. The article surveys the experience of countries that managed to transform their economy to the innovative one. Ukrainian economy cannot stand aside processes that dominate the world economy trends, thus we are to use this experience to succeed in future. Today any government of the world is facing challenges that occur due to transformation of the economy into informational one. This type of economy causes its transformation form extensive to intensive one. The main reasons under that is limitation of nature resources, material factors of production. Thus this approach depends much on the quality of working force. Unfortunately in Ukraine there is a misbalance in specialist preparation. This puts additional pressure on the educational sphere also. In order to avoid this pressure we are to conduct reforms in education sphere. Nowadays, in the world views and concepts of governmental role in the social development are changing. This why, even at times of economic recession educational costs are not reduced under the new economical doctrine in the EU. Highly qualified specialists, while creating new products and services play role of engineers in XXI century. They are to lead their industries to world leading positions. From economic point of view, highly qualified specialists benefit society with higher income rates, taxation and thus, increasing the living standards in society. Thus, the majority if modern scientists prove the importance of highly trained working force for more effective economic development.

  18. 29 CFR 2520.104-46 - Waiver of examination and report of an independent qualified public accountant for employee...

    Science.gov (United States)

    2010-07-01

    ... qualified public accountant for employee benefit plans with fewer than 100 participants. 2520.104-46 Section... Requirements § 2520.104-46 Waiver of examination and report of an independent qualified public accountant for... public accountant to conduct an examination of the financial statements of the plan; (2) Include within...

  19. Radiation-Resistant Photon-Counting Detector Package Providing Sub-ps Stability for Laser Time Transfer in Space

    Science.gov (United States)

    Prochzaka, Ivan; Kodat, Jan; Blazej, Josef; Sun, Xiaoli (Editor)

    2015-01-01

    We are reporting on a design, construction and performance of photon-counting detector packages based on silicon avalanche photodiodes. These photon-counting devices have been optimized for extremely high stability of their detection delay. The detectors have been designed for future applications in fundamental metrology and optical time transfer in space. The detectors have been qualified for operation in space missions. The exceptional radiation tolerance of the detection chip itself and of all critical components of a detector package has been verified in a series of experiments.

  20. 48 CFR 809.270 - Qualified products for convenience/labor-saving foods.

    Science.gov (United States)

    2010-10-01

    ... convenience/labor-saving foods. 809.270 Section 809.270 Federal Acquisition Regulations System DEPARTMENT OF... 809.270 Qualified products for convenience/labor-saving foods. (a) Each VISN Nutrition and Food Service representative is authorized to establish a common VISN QPL for convenience and labor-saving foods...

  1. A versatile electrical penetration design qualified to IEEE Std. 317-1983

    International Nuclear Information System (INIS)

    Lankenau, W.; Wetherill, T.M.

    1994-01-01

    Although worldwide demand for new construction of nuclear power stations has been on a decline, the available opportunities for the design and construction of qualified electrical penetrations continues to offer challenges, requiring a highly versatile design. Versatility is necessary in order to meet unique customer requirements within the constraints of a design basis qualified to IEEE Std. 317-1983. This paper summarizes such a versatile electrical penetration designed, built and tested to IEEE Std. 317-1983. The principal features are described including major materials of construction. Some of the design constraints such as sealing requirements, and conductor density (including numerical example) are discussed. The requirements for qualification testing of the penetration assembly to IEEE Std. 317-1983 are delineated in a general sense, and some typical test ranges for preconditioning, radiation exposure, and LOCA are provided. The paper concludes by describing ways in which this versatile design has been adapted to meet unique customer requirements in a variety of nuclear power plants

  2. Developing Viable Financing Models for Space Tourism

    Science.gov (United States)

    Eilingsfeld, F.; Schaetzler, D.

    2002-01-01

    Increasing commercialization of space services and the impending release of government's control of space access promise to make space ventures more attractive. Still, many investors shy away from going into the space tourism market as long as they do not feel secure that their return expectations will be met. First and foremost, attracting investors from the capital markets requires qualifying financing models. Based on earlier research on the cost of capital for space tourism, this paper gives a brief run-through of commercial, technical and financial due diligence aspects. After that, a closer look is taken at different valuation techniques as well as alternative ways of streamlining financials. Experience from earlier ventures has shown that the high cost of capital represents a significant challenge. Thus, the sophistication and professionalism of business plans and financial models needs to be very high. Special emphasis is given to the optimization of the debt-to-equity ratio over time. The different roles of equity and debt over a venture's life cycle are explained. Based on the latter, guidelines for the design of an optimized loan structure are given. These are then applied to simulating the financial performance of a typical space tourism venture over time, including the calculation of Weighted Average Cost of Capital (WACC) and Net Present Value (NPV). Based on a concluding sensitivity analysis, the lessons learned are presented. If applied properly, these will help to make space tourism economically viable.

  3. Roles and Responsibilities, and Education and Training Requirements for Clinically Qualified Medical Physicists (Russian Edition)

    International Nuclear Information System (INIS)

    2014-01-01

    This publication addresses the shortfall of well trained and clinically qualified medical physicists working in radiation medicine. The roles, responsibilities and clinical training requirements of medical physicists have not always been well defined or well understood by health care professionals, health authorities and regulatory agencies. To fill this gap, this publication provides recommendations for the academic education and clinical training of clinically qualified medical physicists, including recommendations for their accreditation certification and registration, along with continuous professional development. The goal is to establish criteria that support the harmonization of education and clinical training worldwide

  4. Computers for Manned Space Applications Base on Commercial Off-the-Shelf Components

    Science.gov (United States)

    Vogel, T.; Gronowski, M.

    2009-05-01

    Similar to the consumer markets there has been an ever increasing demand in processing power, signal processing capabilities and memory space also for computers used for science data processing in space. An important driver of this development have been the payload developers for the International Space Station, requesting high-speed data acquisition and fast control loops in increasingly complex systems. Current experiments now even perform video processing and compression with their payload controllers. Nowadays the requirements for a space qualified computer are often far beyond the capabilities of, for example, the classic SPARC architecture that is found in ERC32 or LEON CPUs. An increase in performance usually demands costly and power consuming application specific solutions. Continuous developments over the last few years have now led to an alternative approach that is based on complete electronics modules manufactured for commercial and industrial customers. Computer modules used in industrial environments with a high demand for reliability under harsh environmental conditions like chemical reactors, electrical power plants or on manufacturing lines are entered into a selection procedure. Promising candidates then undergo a detailed characterisation process developed by Astrium Space Transportation. After thorough analysis and some modifications, these modules can replace fully qualified custom built electronics in specific, although not safety critical applications in manned space. This paper focuses on the benefits of COTS1 based electronics modules and the necessary analyses and modifications for their utilisation in manned space applications on the ISS. Some considerations regarding overall systems architecture will also be included. Furthermore this paper will also pinpoint issues that render such modules unsuitable for specific tasks, and justify the reasons. Finally, the conclusion of this paper will advocate the implementation of COTS based

  5. 76 FR 64879 - Deduction for Qualified Film and Television Production Costs

    Science.gov (United States)

    2011-10-19

    ... Deduction for Qualified Film and Television Production Costs AGENCY: Internal Revenue Service (IRS... regulations relating to deductions for the costs of producing film and television productions. Those temporary... production costs. (a) * * * (1) * * * (ii) [The text of this proposed amendment to Sec. 1.181- 1(a)(1)(ii) is...

  6. Newly Qualified Teachers' Professional Digital Competence: Implications for Teacher Education

    Science.gov (United States)

    Gudmundsdottir, Greta Björk; Hatlevik, Ove Edvard

    2018-01-01

    The professional digital competence (PDC) of teachers is of growing importance in classrooms, now that digital resources and digital media are becoming important parts of teachers' everyday practice. This study explores how newly qualified teachers are prepared to use information and communication technology (ICT) in their initial teacher…

  7. 42 CFR 423.884 - Requirements for qualified retiree prescription drug plans.

    Science.gov (United States)

    2010-10-01

    ... actuary who is a member of the American Academy of Actuaries. Applicants may use qualified outside actuaries, including (but not limited to) actuaries employed by the plan administrator or an insurer providing benefits under the plan. If an applicant uses an outside actuary, the attestation can be submitted...

  8. Program Director Perceptions of Proficiency in the Core Entrustable Professional Activities.

    Science.gov (United States)

    Pearlman, R Ellen; Pawelczak, Melissa; Yacht, Andrew C; Akbar, Salaahuddin; Farina, Gino A

    2017-10-01

    The Association of American Medical Colleges describes 13 core entrustable professional activities (EPAs) that every graduating medical student should be expected to perform proficiently on day 1 of residency, regardless of chosen specialty. Studies have shown wide variability in program director (PD) confidence in interns' abilities to perform these core EPAs. Little is known regarding comparison of United States Medical Licensing Examination (USMLE) scores with proficiency in EPAs. We determined if PDs from a large health system felt confident in their postgraduate year 1 residents' abilities to perform the 13 core EPAs, and compared perceived EPA proficiency with USMLE Step 1 and Step 2 scores. The PDs were asked to rate their residents' proficiency in each EPA and to provide residents' USMLE scores. Timing coincided with the reporting period for resident milestones. Surveys were completed on 204 of 328 residents (62%). PDs reported that 69% of residents (140 of 204) were prepared for EPA 4 (orders/prescriptions), 61% (117 of 192) for EPA 7 (form clinical questions), 68% (135 of 198) for EPA 8 (handovers), 63% (116 of 185) for EPA 11 (consent), and 38% (49 of 129) for EPA 13 (patient safety). EPA ratings and USMLE 1 and 2 were negatively correlated ( r (101) = -0.23, P  = .031). PDs felt that a significant percentage of residents were not adequately prepared in order writing, forming clinical questions, handoffs, informed consent, and promoting a culture of patient safety. We found no positive association between USMLE scores and EPA ratings.

  9. Learning and study strategies correlate with medical students' performance in anatomical sciences.

    Science.gov (United States)

    Khalil, Mohammed K; Williams, Shanna E; Gregory Hawkins, H

    2018-05-06

    Much of the content delivered during medical students' preclinical years is assessed nationally by such testing as the United States Medical Licensing Examination ® (USMLE ® ) Step 1 and Comprehensive Osteopathic Medical Licensing Examination ® (COMPLEX-USA ® ) Step 1. Improvement of student study/learning strategies skills is associated with academic success in internal and external (USMLE Step 1) examinations. This research explores the strength of association between the Learning and Study Strategies Inventory (LASSI) scores and student performance in the anatomical sciences and USMLE Step 1 examinations. The LASSI inventory assesses learning and study strategies based on ten subscale measures. These subscales include three components of strategic learning: skill (Information processing, Selecting main ideas, and Test strategies), will (Anxiety, Attitude, and Motivation) and self-regulation (Concentration, Time management, Self-testing, and Study aid). During second year (M2) orientation, 180 students (Classes of 2016, 2017, and 2018) were administered the LASSI survey instrument. Pearson Product-Moment correlation analyses identified significant associations between five of the ten LASSI subscales (Anxiety, Information processing, Motivation, Selecting main idea, and Test strategies) and students' performance in the anatomical sciences and USMLE Step 1 examinations. Identification of students lacking these skills within the anatomical sciences curriculum allows targeted interventions, which not only maximize academic achievement in an aspect of an institution's internal examinations, but in the external measure of success represented by USMLE Step 1 scores. Anat Sci Educ 11: 236-242. © 2017 American Association of Anatomists. © 2017 American Association of Anatomists.

  10. Camera memory study for large space telescope. [charge coupled devices

    Science.gov (United States)

    Hoffman, C. P.; Brewer, J. E.; Brager, E. A.; Farnsworth, D. L.

    1975-01-01

    Specifications were developed for a memory system to be used as the storage media for camera detectors on the large space telescope (LST) satellite. Detectors with limited internal storage time such as intensities charge coupled devices and silicon intensified targets are implied. The general characteristics are reported of different approaches to the memory system with comparisons made within the guidelines set forth for the LST application. Priority ordering of comparisons is on the basis of cost, reliability, power, and physical characteristics. Specific rationales are provided for the rejection of unsuitable memory technologies. A recommended technology was selected and used to establish specifications for a breadboard memory. Procurement scheduling is provided for delivery of system breadboards in 1976, prototypes in 1978, and space qualified units in 1980.

  11. Cryogenic techniques for large superconducting magnets in space

    Science.gov (United States)

    Green, M. A.

    1989-01-01

    A large superconducting magnet is proposed for use in a particle astrophysics experiment, ASTROMAG, which is to be mounted on the United States Space Station. This experiment will have a two-coil superconducting magnet with coils which are 1.3 to 1.7 meters in diameter. The two-coil magnet will have zero net magnetic dipole moment. The field 15 meters from the magnet will approach earth's field in low earth orbit. The issue of high Tc superconductor will be discussed in the paper. The reasons for using conventional niobium-titanium superconductor cooled with superfluid helium will be presented. Since the purpose of the magnet is to do particle astrophysics, the superconducting coils must be located close to the charged particle detectors. The trade off between the particle physics possible and the cryogenic insulation around the coils is discussed. As a result, the ASTROMAG magnet coils will be operated outside of the superfluid helium storage tank. The fountain effect pumping system which will be used to cool the coil is described in the report. Two methods for extending the operating life of the superfluid helium dewar are discussed. These include: operation with a third shield cooled to 90 K with a sterling cycle cryocooler, and a hybrid cryogenic system where there are three hydrogen-cooled shields and cryostat support heat intercept points.

  12. 40 CFR 73.81 - Qualified conservation measures and renewable energy generation.

    Science.gov (United States)

    2010-07-01

    ...)) without increasing the use by the customer of any fuel other than qualified renewable energy, industrial waste heat, or, pursuant to paragraph (b)(5) of this section, industrial waste gases; (ii) Is... pursuant to § 73.82(c); or (5) Utilization of industrial waste gases, unless the applicant has certified...

  13. 26 CFR 1.856-9 - Treatment of certain qualified REIT subsidiaries.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Treatment of certain qualified REIT subsidiaries. 1.856-9 Section 1.856-9 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Real Estate Investment Trusts § 1.856-9 Treatment of certain...

  14. 26 CFR 301.6361-1 - Collection and administration of qualified taxes.

    Science.gov (United States)

    2010-04-01

    ... chapter 1 (and the civil and criminal sanctions provided by subtitle F, or by title 18 of the United States Code (relating to crimes and criminal procedure), with respect to such collection and... for tax of another State or political subdivision—(i) In general. A credit allowable under a qualified...

  15. What Motivates Low-Qualified Employees to Participate in Training and Development? A Mixed-Method Study on their Learning Intentions

    Science.gov (United States)

    Kyndt, Eva; Govaerts, Natalie; Claes, Trees; De La Marche, Jens; Dochy, Filip

    2013-01-01

    The current research starts from the observation that low-qualified employees hold a vulnerable position on the labour market. It has been argued that learning and development can decrease this vulnerability; unfortunately research has shown that low-qualified employees participate considerably less in learning activities in comparison with…

  16. APPROACH TO SYNTHESIS OF PASSIVE INFRARED DETECTORS BASED ON QUASI-POINT MODEL OF QUALIFIED INTRUDER

    Directory of Open Access Journals (Sweden)

    I. V. Bilizhenko

    2017-01-01

    Full Text Available Subject of Research. The paper deals with synthesis of passive infra red (PIR detectors with enhanced detection capability of qualified intruder who uses different types of detection countermeasures: the choice of specific movement direction and disguise in infrared band. Methods. We propose an approach based on quasi-point model of qualified intruder. It includes: separation of model priority parameters, formation of partial detection patterns adapted to those parameters and multi channel signal processing. Main Results. Quasi-pointmodel of qualified intruder consisting of different fragments was suggested. Power density difference was used for model parameters estimation. Criteria were formulated for detection pattern parameters choice on the basis of model parameters. Pyroelectric sensor with nine sensitive elements was applied for increasing the signal information content. Multi-channel processing with multiple partial detection patterns was proposed optimized for detection of intruder's specific movement direction. Practical Relevance. Developed functional device diagram can be realized both by hardware and software and is applicable as one of detection channels for dual technology passive infrared and microwave detectors.

  17. Actions Needed to Ensure Scientific and Technical Information is Adequately Reviewed at Goddard Space Flight Center, Johnson Space Center, Langley Research Center, and Marshall Space Flight Center

    Science.gov (United States)

    2008-01-01

    This audit was initiated in response to a hotline complaint regarding the review, approval, and release of scientific and technical information (STI) at Johnson Space Center. The complainant alleged that Johnson personnel conducting export control reviews of STI were not fully qualified to conduct those reviews and that the reviews often did not occur until after the STI had been publicly released. NASA guidance requires that STI, defined as the results of basic and applied scientific, technical, and related engineering research and development, undergo certain reviews prior to being released outside of NASA or to audiences that include foreign nationals. The process includes technical, national security, export control, copyright, and trade secret (e.g., proprietary data) reviews. The review process was designed to preclude the inappropriate dissemination of sensitive information while ensuring that NASA complies with a requirement of the National Aeronautics and Space Act of 1958 (the Space Act)1 to provide for the widest practicable and appropriate dissemination of information resulting from NASA research activities. We focused our audit on evaluating the STI review process: specifically, determining whether the roles and responsibilities for the review, approval, and release of STI were adequately defined and documented in NASA and Center-level guidance and whether that guidance was effectively implemented at Goddard Space Flight Center, Johnson Space Center, Langley Research Center, and Marshall Space Flight Center. Johnson was included in the review because it was the source of the initial complaint, and Goddard, Langley, and Marshall were included because those Centers consistently produce significant amounts of STI.

  18. Skills upgrading for newly qualified surgeon: Is the district hospital in ...

    African Journals Online (AJOL)

    With adequate surgical activity in these settings, the trainee's confidence is boosted to the point of independence. This skill acquisition is a continuous process, especially so for those who qualify from an exit training program like the one at the University of Nairobi (UON). The continuity is maintained for two years after.

  19. 47 CFR 13.201 - Qualifying for a commercial operator license or endorsement.

    Science.gov (United States)

    2010-10-01

    ... class of license or endorsement specified below must pass, or otherwise receive credit for, the... endorsement. 13.201 Section 13.201 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMERCIAL RADIO OPERATORS Examination System § 13.201 Qualifying for a commercial operator license or endorsement...

  20. Deep Space Habitat Configurations Based on International Space Station Systems

    Science.gov (United States)

    Smitherman, David; Russell, Tiffany; Baysinger, Mike; Capizzo, Pete; Fabisinski, Leo; Griffin, Brand; Hornsby, Linda; Maples, Dauphne; Miernik, Janie

    2012-01-01

    A Deep Space Habitat (DSH) is the crew habitation module designed for long duration missions. Although humans have lived in space for many years, there has never been a habitat beyond low-Earth-orbit. As part of the Advanced Exploration Systems (AES) Habitation Project, a study was conducted to develop weightless habitat configurations using systems based on International Space Station (ISS) designs. Two mission sizes are described for a 4-crew 60-day mission, and a 4-crew 500-day mission using standard Node, Lab, and Multi-Purpose Logistics Module (MPLM) sized elements, and ISS derived habitation systems. These durations were selected to explore the lower and upper bound for the exploration missions under consideration including a range of excursions within the Earth-Moon vicinity, near earth asteroids, and Mars orbit. Current methods for sizing the mass and volume for habitats are based on mathematical models that assume the construction of a new single volume habitat. In contrast to that approach, this study explored the use of ISS designs based on existing hardware where available and construction of new hardware based on ISS designs where appropriate. Findings included a very robust design that could be reused if the DSH were assembled and based at the ISS and a transportation system were provided for its return after each mission. Mass estimates were found to be higher than mathematical models due primarily to the use of multiple ISS modules instead of one new large module, but the maturity of the designs using flight qualified systems have potential for improved cost, schedule, and risk benefits.

  1. Target language use in Modern Language classrooms: perception and change among newly qualified teachers in Scotland

    OpenAIRE

    Lynch, Michael Patrick

    2015-01-01

    In this thesis I investigate the practices and perceptions of some Newly Qualified Teachers (NQTs) of modern foreign languages (MFL) in Scotland in relation to how they use the target language (L2). I seek to answer the questions “In what different ways do student teachers of modern languages use the target language in Scottish secondary school classrooms?’, ‘What reasons do they give for how they use it?” and “In what way(s), if any, do newly qualified teachers of modern language...

  2. Worst-case prediction of normal operating containment temperatures for environmentally qualified equipment

    International Nuclear Information System (INIS)

    Krasnopoler, M.J.; Sundergill, J.E.

    1991-01-01

    Due to issues raised in NRC Information Notice No. 87-65, a southern US nuclear plant was concerned about thermal aging of environmentally qualified (EQ) equipment located in areas of elevated containment temperatures. A method to predict the worst-case monthly temperatures at various zones in the containment and calculate the qualified life using this monthly temperature was developed. Temperatures were predicted for twenty locations inside the containment. Concern about the qualified life of EQ equipment resulted from normal operating temperatures above 120F in several areas of the containment, especially during the summer. At a few locations, the temperature exceeded 140F. Also, NRC Information Notice No. 89-30 reported high containment temperatures at three other nuclear power plants. The predicted temperatures were based on a one-year containment temperature monitoring program. The monitors included permanent temperature monitors required by the Technical Specifications and temporary monitors installed specifically for this program. The temporary monitors were installed near EQ equipment in the expected worst-case areas based on design and operating experience. A semi-empirical model that combined physical and statistical models was developed. The physical model was an overall energy balance for the containment. The statistical model consists of several linear regressions that conservatively relate the monitor temperatures to the bulk containment temperature. The resulting semi-empirical model predicts the worst-case monthly service temperatures at the location of each of the containment temperature monitors. The monthly temperatures are the maximum expected because they are based on the historically worst-case atmospheric data

  3. Qualifying codes under software quality assurance: Two examples as guidelines for codes that are existing or under development

    Energy Technology Data Exchange (ETDEWEB)

    Mangold, D.

    1993-05-01

    Software quality assurance is an area of concem for DOE, EPA, and other agencies due to the poor quality of software and its documentation they have received in the past. This report briefly summarizes the software development concepts and terminology increasingly employed by these agencies and provides a workable approach to scientific programming under the new requirements. Following this is a practical description of how to qualify a simulation code, based on a software QA plan that has been reviewed and officially accepted by DOE/OCRWM. Two codes have recently been baselined and qualified, so that they can be officially used for QA Level 1 work under the DOE/OCRWM QA requirements. One of them was baselined and qualified within one week. The first of the codes was the multi-phase multi-component flow code TOUGH version 1, an already existing code, and the other was a geochemistry transport code STATEQ that was under development The way to accomplish qualification for both types of codes is summarized in an easy-to-follow step-by step fashion to illustrate how to baseline and qualify such codes through a relatively painless procedure.

  4. Qualifying codes under software quality assurance: Two examples as guidelines for codes that are existing or under development

    International Nuclear Information System (INIS)

    Mangold, D.

    1993-05-01

    Software quality assurance is an area of concern for DOE, EPA, and other agencies due to the poor quality of software and its documentation they have received in the past. This report briefly summarizes the software development concepts and terminology increasingly employed by these agencies and provides a workable approach to scientific programming under the new requirements. Following this is a practical description of how to qualify a simulation code, based on a software QA plan that has been reviewed and officially accepted by DOE/OCRWM. Two codes have recently been baselined and qualified, so that they can be officially used for QA Level 1 work under the DOE/OCRWM QA requirements. One of them was baselined and qualified within one week. The first of the codes was the multi-phase multi-component flow code TOUGH version 1, an already existing code, and the other was a geochemistry transport code STATEQ that was under development The way to accomplish qualification for both types of codes is summarized in an easy-to-follow step-by step fashion to illustrate how to baseline and qualify such codes through a relatively painless procedure

  5. 76 FR 71450 - Deduction for Qualified Film and Television Production Costs; Correction

    Science.gov (United States)

    2011-11-18

    ... Deduction for Qualified Film and Television Production Costs; Correction AGENCY: Internal Revenue Service... Register on Wednesday, October 19, 2011 (76 FR 64816) relating to deductions for the cost of producing film and television productions. DATES: This correction is effective on November 18, 2011, and is...

  6. 6 CFR 25.6 - Procedures for designation of qualified anti-terrorism technologies.

    Science.gov (United States)

    2010-01-01

    ...-terrorism technologies. 25.6 Section 25.6 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY REGULATIONS TO SUPPORT ANTI-TERRORISM BY FOSTERING EFFECTIVE TECHNOLOGIES § 25.6 Procedures for designation of qualified anti-terrorism technologies. (a) Application Procedure. Any person, firm or other...

  7. SPACES OF WELLBEING : WHAT IS SO SPECIAL ABOUT SPECIAL NEEDS ART STUDIOS?

    OpenAIRE

    Radcliffe, David

    2013-01-01

    ABSTRACT Radcliffe, David. Spaces of Wellbeing, What is so special about special needs art studios? Autumn 2013, 73 p., 2 appendices. Diaconia University of Applied Sciences, Degree Programme in Social Services + option in Diaconal Social Work, Bachelor of Social Services (UAS) + Qualifi-cation for the office of diaconia worker in The Church of Finland. The aim of this thesis is to discover the common experiences of art studio par-ticipants in relation to wellbeing. This has become a...

  8. Qualifying commercial grade instruments for use in nuclear power generating stations

    International Nuclear Information System (INIS)

    Lamothe, R.J.; Scally, C.R.

    1983-01-01

    Nuclear environmental qualification of instrumentation has been successfully accomplished by many commercial grade equipment manufacturers. This paper was prepared as a guide to those manufacturers who want some insight into a qualification program. The areas addressed are the regulations and documents, the qualification program, and a case history of a chart recorder qualifications. The principal standards relating to a nuclear qualification program are IEEE Std. 323-1974 IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations, IEEE Std. 344-1975 IEEE Recommended Practices for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations and 10CFR50.49. Previously NUREG 0588 Interim Staff Position on Environmental Qualification of Safety-Related Equipment. These define the intent and purpose of the qualification. The qualification program itself consists of several distinct parts which require explanation, including the determination of qualified life, choice of test samples, selection of appropriate acceptance criteria, aging program, radiation testing, seismic testing, abnormal environment tests and others. The case history illustrates the qualification program and the thought processes involved

  9. Space Network Devices Developed

    Science.gov (United States)

    Jones, Robert E.

    2004-01-01

    The NASA Glenn Research Center through a contract with Spectrum Astro, Inc., has been developing space network hardware as an enabling technology using open systems interconnect (OSI) standards for space-based communications applications. The OSI standard is a well-recognized layered reference model that specifies how data should be sent node to node in a communications network. Because of this research and technology development, a space-qualifiable Ethernet-based network interface card (similar to the type found in a networked personal computer) and the associated four-port hub were designed and developed to flight specifications. During this research and development, there also have been many lessons learned for determining approaches for migrating existing spacecraft architectures to an OSI-network-based platform. Industry has recognized the benefits of targeting hardware developed around OSI standards such as Transmission Control Protocol/Internet Protocol (TCP/IP) or similar protocols for use in future generations of space communication systems. Some of these tangible benefits include overall reductions in mission schedule and cost and in system complexity. This development also brings us a step closer to the realization of a principal investigator on a terrestrial Internet site being able to interact with space platform assets in near real time. To develop this hardware, Spectrum Astro first conducted a technology analysis of alternatives study. For this analysis, they looked at the features of three protocol specifications: Ethernet (IEEE 802.3), Firewire (IEEE 1394), and Spacewire (IEEE 1355). A thorough analysis was performed on the basis of criteria such as current protocol performance and suitability for future space applications. Spectrum Astro also projected future influences such as cost, hardware and software availability, throughput performance, and integration procedures for current and transitive space architectures. After a thorough analysis

  10. The design and development of low- and high-voltage ASICs for space-borne CCD cameras

    Science.gov (United States)

    Waltham, N.; Morrissey, Q.; Clapp, M.; Bell, S.; Jones, L.; Torbet, M.

    2017-12-01

    The CCD remains the pre-eminent visible and UV wavelength image sensor in space science, Earth and planetary remote sensing. However, the design of space-qualified CCD readout electronics is a significant challenge with requirements for low-volume, low-mass, low-power, high-reliability and tolerance to space radiation. Space-qualified components are frequently unavailable and up-screened commercial components seldom meet project or international space agency requirements. In this paper, we describe an alternative approach of designing and space-qualifying a series of low- and high-voltage mixed-signal application-specific integrated circuits (ASICs), the ongoing development of two low-voltage ASICs with successful flight heritage, and two new high-voltage designs. A challenging sub-system of any CCD camera is the video processing and digitisation electronics. We describe recent developments to improve performance and tolerance to radiation-induced single event latchup of a CCD video processing ASIC originally developed for NASA's Solar Terrestrial Relations Observatory and Solar Dynamics Observatory. We also describe a programme to develop two high-voltage ASICs to address the challenges presented with generating a CCD's bias voltages and drive clocks. A 0.35 μm, 50 V tolerant, CMOS process has been used to combine standard low-voltage 3.3 V transistors with high-voltage 50 V diffused MOSFET transistors that enable output buffers to drive CCD bias drains, gates and clock electrodes directly. We describe a CCD bias voltage generator ASIC that provides 24 independent and programmable 0-32 V outputs. Each channel incorporates a 10-bit digital-to-analogue converter, provides current drive of up to 20 mA into loads of 10 μF, and includes current-limiting and short-circuit protection. An on-chip telemetry system with a 12-bit analogue-to-digital converter enables the outputs and multiple off-chip camera voltages to be monitored. The ASIC can drive one or more CCDs and

  11. Gender Inequalities in Highly Qualified Professions: A Social Psychological Analysis

    OpenAIRE

    Santos, Maria Helena; Amâncio, Lígia

    2016-01-01

    Research in social and political psychology contributes towards understanding the persistence of job market gender segregation prevailing in recent decades, the consequences for those involved and their reactions when having to cope with gender inequality. Within the framework of the literature on shared ideologies that justify and legitimize discrimination against women, this article focuses on Portugal and analyses the particular case of women in two highly qualified professions traditional...

  12. Improvement of technique of a jerk of the qualified sportswomen in weightlifting

    Directory of Open Access Journals (Sweden)

    Oksana Solodka

    2016-12-01

    Full Text Available Purpose: the improvement of technical preparedness of the qualified female weight-lifters taking into account the group model characteristics of technique of a jerk. Material & Methods: analysis and synthesis of data of scientific and methodical literature, pedagogical experiment, method of mathematical statistics. Results: the revealed shortcomings of technique of the execution of a jerk of the qualified female weight-lifters were, considering the group model characteristics of technique of a jerk of the first group of weight categories. Complexes of compensatory exercises were offered for the purpose of correction. Conclusions: the performance of complexes of the compensatory exercises, which are directed to the improvement of competitive exercise of a jerk of bar, allowed to increase the number of successfully executed raising of bar, for 10,3–19,8%, according to initial indicators of number of rises, and also to receive positive shifts in motive structure of a jerk of bar.

  13. High-Performance, Space-Storable, Bi-Propellant Program Status

    Science.gov (United States)

    Schneider, Steven J.

    2002-01-01

    Bipropellant propulsion systems currently represent the largest bus subsystem for many missions. These missions range from low Earth orbit satellite to geosynchronous communications and planetary exploration. The payoff of high performance bipropellant systems is illustrated by the fact that Aerojet Redmond has qualified a commercial NTO/MMH engine based on the high Isp technology recently delivered by this program. They are now qualifying a NTO/hydrazine version of this engine. The advanced rhenium thrust chambers recently provided by this program have raised the performance of earth storable propellants from 315 sec to 328 sec of specific impulse. The recently introduced rhenium technology is the first new technology introduced to satellite propulsion in 30 years. Typically, the lead time required to develop and qualify new chemical thruster technology is not compatible with program development schedules. These technology development programs must be supported by a long term, Base R&T Program, if the technology s to be matured. This technology program then addresses the need for high performance, storable, on-board chemical propulsion for planetary rendezvous and descent/ascent. The primary NASA customer for this technology is Space Science, which identifies this need for such programs as Mars Surface Return, Titan Explorer, Neptune Orbiter, and Europa Lander. High performance (390 sec) chemical propulsion is estimated to add 105% payload to the Mars Sample Return mission or alternatively reduce the launch mass by 33%. In many cases, the use of existing (flight heritage) propellant technology is accommodated by reducing mission objectives and/or increasing enroute travel times sacrificing the science value per unit cost of the program. Therefore, a high performance storable thruster utilizing fluorinated oxidizers with hydrazine is being developed.

  14. Can Social Robots Qualify for Moral Consideration? Reframing the Question about Robot Rights

    Directory of Open Access Journals (Sweden)

    Herman T. Tavani

    2018-03-01

    Full Text Available A controversial question that has been hotly debated in the emerging field of robot ethics is whether robots should be granted rights. Yet, a review of the recent literature in that field suggests that this seemingly straightforward question is far from clear and unambiguous. For example, those who favor granting rights to robots have not always been clear as to which kinds of robots should (or should not be eligible; nor have they been consistent with regard to which kinds of rights—civil, legal, moral, etc.—should be granted to qualifying robots. Also, there has been considerable disagreement about which essential criterion, or cluster of criteria, a robot would need to satisfy to be eligible for rights, and there is ongoing disagreement as to whether a robot must satisfy the conditions for (moral agency to qualify either for rights or (at least some level of moral consideration. One aim of this paper is to show how the current debate about whether to grant rights to robots would benefit from an analysis and clarification of some key concepts and assumptions underlying that question. My principal objective, however, is to show why we should reframe that question by asking instead whether some kinds of social robots qualify for moral consideration as moral patients. In arguing that the answer to this question is “yes,” I draw from some insights in the writings of Hans Jonas to defend my position.

  15. Strategy for development modes competent performance in teachers qualified alternative

    Directory of Open Access Journals (Sweden)

    Sailí Rodríguez Fuentes

    2017-12-01

    Full Text Available Introduction: the process of professionalization of the teacher is a subject of contemporary conjuncture, which is debated and investigated by researchers from dissimilar edges. Objective: to contribute to the professionalization process of qualified teachers of Technical and Vocational Education through a pedagogical strategy. Materials and methods: The materialist dialectic is used as a general method, allowing the study of the object as a process, the determination of its components, as well as its contradictions. theoretical methods: the historical and logical to delve into the regularities and qualities of reality in the polytechnic centers. Essential empirical methods were used: the documentary analysis that included the professional model; study plans, to obtain authentic and reliable information for research, interviews with students with the purpose of analyzing the manifestations of the professionalization process of the students and the direction of the process by the teachers, the observation of teaching activities allowed to diagnose the object , the demonstration of the problem, as well as the results of the practice of the strategy to be implemented. Results: a pedagogical strategy is designed and implemented to perfect the competent professional performance modes in the qualified professors. Conclusions: it contributed to the improvement of the professionalization process in favor of the competent professional modes of action.

  16. 'Newness-struggle-success' continuum: a qualitative examination of the cultural adaptation process experienced by overseas-qualified dentists in Australia.

    Science.gov (United States)

    Balasubramanian, Madhan; Brennan, David S; Spencer, A John; Short, Stephanie D

    2016-04-01

    Objectives Overseas-qualified dentists constitute a significant proportion of the Australian dental workforce (approximately one in four). The aim of the present study was to provide a better understanding of the cultural adaptation process of overseas-qualified dentists in Australia, so as to facilitate their integration into the Australian way of life and improve their contribution to Australian healthcare, economy and society. Methods Life stories of 49 overseas-qualified dentists from 22 countries were analysed for significant themes and patterns. We focused on their settlement experience, which relates to their social and cultural experience in Australia. This analysis was consistent with a hermeneutic phenomenological approach to qualitative social scientific research. Results Many participants noted that encounters with 'the Australian accent' and 'slang' influenced their cultural experience in Australia. Most of the participants expressed 'fascination' with the people and lifestyle in Australia, primarily with regard to the relaxed way of life, cultural diversity and the freedom one usually experiences living in Australia. Few participants expressed 'shock' at not being able to find a community of similar religious faith in Australia, as they are used to in their home countries. These issues were analysed in two themes; (1) language and communication; and (2) people, religion and lifestyle. The cultural adaptation process of overseas-qualified dentists in Australia is described as a continuum or superordinate theme, which we have entitled the 'newness-struggle-success' continuum. This overarching theme supersedes and incorporates all subthemes. Conclusion Family, friends, community and organisational structures (universities and public sector) play a vital role in the cultural learning process, affecting overseas-qualified dentist's ability to progress successfully through the cultural continuum. What is known about the topic? Australia is a popular host

  17. Qualified market access and inter-disciplinarity

    Directory of Open Access Journals (Sweden)

    Lisa Herzog

    2014-05-01

    Full Text Available This note offers reflections on qualified market access (QMA—the practice of linking trade agreements to values such as human rights, labour standards, or environmental protection. This idea has been suggested by political theorists as a way of fulfilling our duties to the global poor and of making the global economic system more just, and it has influenced a number of concrete policies, such as European Union (EU trade policies. Yet, in order to assess its merits tout court, different perspectives and disciplines need to be brought together, such as international law, economics, political science, and philosophy. It is also worth reflecting on existing practices, such as those of the EU. This note summarises some insights about QMA by drawing such research together and considers the areas in which further research is needed, whilst reflecting also on the merits of interdisciplinary exchanges on such topics.

  18. Advancement of High Power Quasi-CW Laser Diode Arrays For Space-based Laser Instruments

    Science.gov (United States)

    Amzajerdian, Farzin; Meadows, Byron L.; Baker, nathaniel R.; Baggott, Renee S.; Singh, Upendra N.; Kavaya, Michael J.

    2004-01-01

    Space-based laser and lidar instruments play an important role in NASA s plans for meeting its objectives in both Earth Science and Space Exploration areas. Almost all the lidar instrument concepts being considered by NASA scientist utilize moderate to high power diode-pumped solid state lasers as their transmitter source. Perhaps the most critical component of any solid state laser system is its pump laser diode array which essentially dictates instrument efficiency, reliability and lifetime. For this reason, premature failures and rapid degradation of high power laser diode arrays that have been experienced by laser system designers are of major concern to NASA. This work addresses these reliability and lifetime issues by attempting to eliminate the causes of failures and developing methods for screening laser diode arrays and qualifying them for operation in space.

  19. 26 CFR 1.1202-2 - Qualified small business stock; effect of redemptions.

    Science.gov (United States)

    2010-04-01

    ... purchased from the decedent's estate, beneficiary (whether by bequest or lifetime gift), heir, surviving.... Stock acquired by a taxpayer is not qualified small business stock if, in one or more purchases during... corporation purchases (directly or indirectly) more than a de minimis amount of its stock from the taxpayer or...

  20. Free-piston Stirling technology for space power

    International Nuclear Information System (INIS)

    Slaby, J.G.

    1994-01-01

    An overview is presented of the NASA Lewis Research Center free-piston Stirling engine activities directed toward space power. This work is being carried out under NASA's new Civil Space Technology Initiative (CSTI). The overall goal of CSTI's High Capacity Power element is to develop the technology base needed to meet the long duration, high capacity power requirements for future NASA space missions. The Stirling cycle offers an attractive power conversion concept for space power needs. Discussed in this paper is the completion of the Space Power Demonstrator Engine (SPDE) testing - culminating in the generation of 25 kW of engine power from a dynamically-balanced opposed-piston Stirling engine at a temperature ratio of 2.0. Engine efficiency was approximately 22 percent. The SPDE recently has been divided into two separate single-cylinder engines, called Space Power Research Engines (SPRE), that now serve as test beds for the evaluation of key technology disciplines. These disciplines include hydrodynamic gas bearings, high-efficiency linear alternators, space qualified heat pipe heat exchangers, oscillating flow code validation, and engine loss understanding. The success of the SPDE at 650 K has resulted in a more ambitious Stirling endeavor - the design, fabrication, test and evaluation of a designed-for-space 25 kW per cylinder Stirling Space Engine (SSE). The SSE will operate at a hot metal temperature of 1050 K using superalloy materials. This design is a low temperature confirmation of the 1300 K design. It is the 1300 K free-piston Stirling power conversion system that is the ultimate goal; to be used in conjunction with the SP-100 reactor. The approach to this goal is in three temperature steps. However, this paper concentrates on the first two phases of this program - the 650 K SPDE and the 1050 K SSE

  1. Bank Officers’ Perceptions and Uses of Qualified Audit Reports

    DEFF Research Database (Denmark)

    Sormunen, Nina

    2014-01-01

    Purpose – The purpose of this study is to provide insights into the perceptions and uses of qualified audit reports in financial statements of small- and medium-sized enterprises (SMEs). As there is a long-standing debate on the usefulness of auditor’s going-concern reports, this study aims....... Practical implications – Regulators have taken the action to improve the auditor’s reporting model, and the findings provided by this study are important because they provide a deeper understanding of the perceptions and uses of audit reports from smaller companies. The study also contributes knowledge...

  2. 26 CFR 1.593-8 - Allocation of pre-1952 surplus to opening balance of reserve for losses on qualifying real...

    Science.gov (United States)

    2010-04-01

    ... real property loans shall not be treated as a reserve for bad debts for any purpose other than... of reserve for losses on qualifying real property loans. 1.593-8 Section 1.593-8 Internal Revenue... for losses on qualifying real property loans. (a) General rule. In the case of a taxpayer described in...

  3. Qualifying for Career Planning

    Directory of Open Access Journals (Sweden)

    Aleksandra Kovač

    1996-12-01

    Full Text Available The need for education in various spheres of life, which allows a person to fully develop his/her personality, is more and more presen t also in our society. The discussed educational programme Discovering Vocational Goals and Forming Strategies· to Realize them qualifies people for autonomous career planning by offer­ ing them one of the possible ways of making decisions in relation to profession and job. In the course of the realization of the programme the participants are given the chance to think about the kind of work that would suit their interests, capabilities and individual characteristics as weel as the needs in certain environments (possible employers. They are encouraged to make an actual plan, stating how and when the desired objective will be reached. In 1995 the pro­ gramme was being carried out within nine semi­ nars organized at the Employment Offices in Maribor and Ptuj. During that time the pro­ gramme has also been evaluated by Doba - Education Office, which was funded by the Ministry of Work, Family and Social Matters. The paper includes the content of the programme as well as the assessments of the research project. The presented data show that the participants learned the method of career planning and acqu­ired greater self-confidence and motivation to solve their job problem actively.

  4. Learning style preferences of surgical residency applicants.

    Science.gov (United States)

    Kim, Roger H; Gilbert, Timothy

    2015-09-01

    The learning style preferences of general surgery residents have been previously reported; there is evidence that residents who prefer read/write learning styles perform better on the American Board of Surgery In-Training Examination (ABSITE). However, little is known regarding the learning style preferences of applicants to general surgery residency and their impact on educational outcomes. In this study, the preferred learning styles of surgical residency applicants were determined. We hypothesized that applicant rank data are associated with specific learning style preferences. The Fleming VARK learning styles inventory was offered to all general surgery residency applicants that were interviewed at a university hospital-based program. The VARK model categorizes learners as visual (V), aural (A), read/write (R), kinesthetic (K), or multimodal (MM). Responses on the inventory were scored to determine the preferred learning style for each applicant. Applicant data, including United States Medical Licensing Examination (USMLE) scores, class rank, interview score, and overall final applicant ranking, were examined for association with preferred learning styles. Sixty-seven applicants were interviewed. Five applicants were excluded due to not completing the VARK inventory or having incomplete applicant data. The remaining 62 applicants (92%) were included for analysis. Most applicants (57%) had a multimodal preference. Sixty-nine percent of all applicants had some degree of preference for kinesthetic learning. There were statistically significant differences between applicants of different learning styles in terms of USMLE step 1 scores (P = 0.001) and USMLE step 2 clinical knowledge scores (P = 0.01), but not for class ranks (P = 0.27), interview scores (P = 0.20), or final ranks (P = 0.14). Multiple comparison analysis demonstrated that applicants with aural preferences had higher USMLE 1 scores (233.2) than those with kinesthetic (211.8, P = 0.005) or multimodal

  5. Information Support of Highly-Qualified Archers’ Training

    Directory of Open Access Journals (Sweden)

    А. П. Власов

    2017-03-01

    Full Text Available The objective is to ground the ways of improving the level of technical preparedness of highly-qualified archers by means of video and multimedia technologies. Materials and methods: The research studied motor actions of 25 athletes of the national team of Ukraine in archery when they were performing training exercises indoors (exercising area and outdoors (archery range. Each athlete’s technique of executing shooting exercises was video recorded in sequence from different angles (from above, from behind, from the front, from the left and the right sides depending on the shooting line with a digital video camera Sony DCR-XR150E. The processing of the video materials was done with the Dartfish Connekt software package. Results: The research grounds the need to use video and multimedia technologies in the process of training of highly-qualified archers. Such methods aim at improving the skills of both coaches and athletes by helping them better understand all aspects of the training exercises execution. Multimedia means offer a delayed-in-time opportunity to watch the video recording of the training after its preliminary computer processing. It enables the coach and the athlete to focus on the analysis of the execution of the entire exercise and its elements. The paper provides examples of the use of video technologies in archers’ training practice. Conclusions: Prospects of the use of the state-of-the-art computer technologies in sports training are infinite. Computer software and hardware systems should be available for most coaches. The task of the latter is to learn to use and implement them for the benefit of themselves and athletes. The task of the scientific groups and experts is to find a most convenient way for the coach to use the innovative technologies. The task of the software developer is to model intellectual programs to help the coach effectively analyze and evaluate his archers or team when preparing them for the most

  6. 26 CFR 1.25-4T - Qualified mortgage credit certificate program (Temporary).

    Science.gov (United States)

    2010-04-01

    ... designed to ensure that only those individuals who could not otherwise purchase a residence will benefit... may be issued in connection with the qualified rehabilitation of a residence part of the cost of which... surrendered to other issuers during the calendar year, (v) The date and amount of any previous elections under...

  7. Wanted, A National Teacher Supply Policy for Education:The Right Way to Meet The "Highly Qualified Teacher" Challenge

    Directory of Open Access Journals (Sweden)

    Linda Darling-Hammond

    2003-09-01

    Full Text Available Teacher quality is now the focus of unprecedented policy analysis. To achieve its goals, the No Child Left Behind Act (NCLB requires a “highly qualified teacher” in all classrooms. The concern with teacher quality has been driven by a growing recognition, fueled by accumulating research evidence, of how critical teachers are to student learning. To acquire and retain high-quality teachers in our Nation’s classrooms will require substantial policy change at many levels. There exists longstanding precedent and strong justification for Washington to create a major education manpower program. Qualified teachers are a critical national resource that requires federal investment and cross-state coordination as well as other state and local action. NCLB provides a standard for equitable access to teacher quality that is both reasonable and feasible. Achieving this goal will require a new vision of the teacher labor market and the framing of a national teacher supply policy. States and local districts have vital roles to play in ensuring a supply of highly qualified teachers; however, they must be supported by appropriate national programs. These programs should be modeled on U.S. medical manpower efforts, which have long supplied doctors to high- need communities and eased shortages in specific health fields. We argue that teacher supply policy should attract well-prepared teachers to districts that sorely need them while relieving shortages in fields like special education, math and the physical sciences. We study the mal-distribution of teachers and examine its causes. We describe examples of both states and local school districts that have fashioned successful strategies for strengthening their teaching forces. Unfortunately, highly successful state and local program to meet the demand for qualified teachers are the exception rather than the rule. They stand out amid widespread use of under-prepared teachers and untrained aides, mainly for

  8. Cryogenic techniques for large superconducting magnets in space

    International Nuclear Information System (INIS)

    Green, M.A.

    1988-12-01

    A large superconducting magnet is proposed for use in a particle astrophysics experiment, ASTROMAG, which is to be mounted on the United States Space Station. This experiment will have a two-coil superconducting magnet with coils which are 1.3 to 1.7 meters in diameter. The two-coil magnet will have zero net magnetic dipole moment. The field 15 meters from the magnet will approach earth's field in low earth orbit. The issue of high Tc superconductor will be discussed in the paper. The reasons for using conventional niobium-titanium superconductor cooled with superfluid helium will be presented. Since the purpose of the magnet is to do particle astrophysics, the superconducting coils must be located close to the charged particle detectors. The trade off between the particle physics possible and the cryogenic insulation around the coils is discussed. As a result, the ASTROMAG magnet coils will be operated outside of the superfluid helium storage tank. The fountain effect pumping system which will be used to cool the coil is described in the report. Two methods for extending the operating life of the superfluid helium dewar are discussed. These include: operation with a third shield cooled to 90 K with a sterling cycle cryocooler, and a hybrid cryogenic system where there are three hydrogen-cooled shields and cryostat support heat intercept points. Both of these methods will extend the ASTROMAG cryogenic operating life from 2 years to almost 4 years. 14 refs., 8 figs., 4 tabs

  9. A Dual Operational Refrigerator/Flow Cryostat with Wide Bore Medium Field Magnet for Application Demonstration

    Science.gov (United States)

    Young, E. A.; Bailey, W. O. S.; Al-Mosawi, M. K.; Beduz, C.; Yang, Y.; Chappell, S.; Twin, A.

    Since stand alone cryocooler systems have become more widely available, there has been increased commercial interest in superconductor applications in the temperature range intermediate to liquid helium and liquid nitrogen. There are however few facilities that have large in-field bore size with variable temperatures. A large bore system can reduce costs associated with full scale demonstration magnets by testing smaller coils and qualify medium length (up to meters) conductors. A 5 T, wide bore, (170 mm) Nb3Sn Oxford Instrument magnet has been integrated into a custom built dual mode refrigerator/helium flow cryostat with 600A HTS current leads. In one mode the system can be used with zero field without cost of liquid helium relying for cooling on a Sumitomo GM cryocooler with 1.5W at 4.2K: (no He) this can be used either as the sole characterisation method, or as a preliminary check before more expensive and extensive measurements are taken. The first measurements using MgB2 wire from 10 to 20K were made using a transient current step of ∼5s duration, as opposed to a DC measurement. This has the advantage of not requiring thermal equilibrium to be achieved at nominal current. The feasibility of this technique for determining critical transport properties is discussed.

  10. 40 CFR 35.4190 - How does my group identify a qualified technical advisor?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false How does my group identify a qualified technical advisor? 35.4190 Section 35.4190 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS...: (1) Demonstrated knowledge of hazardous or toxic waste issues, relocation issues, redevelopment...

  11. 38 CFR 21.6519 - Eligibility of qualified veterans for employment and counseling services.

    Science.gov (United States)

    2010-07-01

    ... veterans for employment and counseling services. 21.6519 Section 21.6519 Pensions, Bonuses, and Veterans... employment and counseling services. (a) General. A qualified veteran for whom vocational rehabilitation and achievenment of a vocational goal are reasonably feasible may be provided the employment and counseling...

  12. Attitude to e-learning among newly qualified doctors.

    Science.gov (United States)

    Goh, Jason; Clapham, Michael

    2014-02-01

    e-Learning plays an increasingly important role in medical education. Much research has focused on the evaluation of individual modules among medical students or more senior trainee doctors. We studied the attitude of newly qualified foundation level-1 doctors (FY1s) towards a blended learning programme to gain insight into the perceived role of e-learning in relation to classroom and experiential learning. The blended learning strategy consisted of weekly 3-hour sessions of lectures and flexible e-learning sessions. A questionnaire survey was conducted among 54 per cent (37/69) of FY1 doctors, towards the end of their first year post qualification. The majority of FY1s had to carry out additional e-learning outside of work. When asked where was best to carry out e-learning, 54 per cent preferred to e-learn both at work and at home, whereas 38 per cent preferred to e-learn outside of work exclusively. An equal preference for a classroom-only strategy and a blended programme was reported. Seventy-three per cent of the FY1s thought that e-learning should not be part of their compulsory weekly teaching programme. Fifty-four per cent of FY1s thought that e-learning had been useful for their education and training in their FY1 year. The e-learning package cited as being most useful was the safe prescribing e-programme, pioneered locally. Newly qualified doctors value e-learning as an adjunct to experiential and lecture-based teaching, and most prefer it as part of a blended learning programme at work or at home. Medical educators must place equal emphasis on the delivery and administration of e-learning as well as on the course design. © 2014 John Wiley & Sons Ltd.

  13. RERTR program progress in qualifying reduced-enrichment fuels

    International Nuclear Information System (INIS)

    Snelgrove, James L.

    1983-01-01

    In order to provide the technical means for reducing the enrichment of uranium used to fuel research and test reactors, the U.S. Reduced Enrichment Research and Test Reactor (RERTR) Program has been engaged in the development and testing of higher-uranium-density fuels than had been used previously. This fuel development effort included work to increase the density of fuels which were being used at the time the Program began and work on a fuel with the potential for much higher density. The ultimate goal of the fuel development and testing phase of the Program is to 'qualify' the fuel for use. A fuel is considered qualified when a sufficient data base for the fuel exists that it can be approved by regulating bodies for use in reactors. To convert a core to the use of reduced-enrichment fuel it is necessary to show that the core will behave properly during normal and off-normal operating conditions and to show that the fuel will behave properly to a reasonable margin beyond the conditions expected during normal operation. It is this latter area that this paper will address. The main characteristics to be considered in evaluating the performance of a fuel are its swelling, its blister-threshold temperature, and its metallurgical appearance. Data for the qualification of the reduced-enrichment fuels being developed by the RERTR Program are obtained from examination of miniature fuel plates (miniplates) which successfully pass the irradiation screening tests and from examinations of full-sized fuel elements. This paper will summarize the miniplate data reported in other papers presented during this meeting and will give the status of full-sized element irradiations. Finally, the current status of qualification of the various fuel types will be discussed and some projections of the future will be given

  14. 26 CFR 26.2652-2 - Special election for qualified terminable interest property.

    Science.gov (United States)

    2010-04-01

    ... executor) may elect to treat the trust as two separate trusts, one of which has a zero inclusion ratio by... leaving $4 million in trust for the benefit of T's surviving spouse, S. On January 16, 1995, T's executor filed T's Form 706 on which the executor elects to treat the entire trust as qualified terminable...

  15. New models to support the professional education of health visitors: A qualitative study of the role of space and place in creating 'community of learning hubs'.

    Science.gov (United States)

    Donetto, Sara; Malone, Mary; Sayer, Lynn; Robert, Glenn

    2017-07-01

    In response to a policy-driven workforce expansion in England new models of preparing health visitors for practice have been implemented. 'Community of Learning hubs' (COLHs) are one such model, involving different possible approaches to student support in clinical practice placements (for example, 'long arm mentoring' or 'action learning set' sessions). Such models present opportunities for studying the possible effects of spatiality on the learning experiences of students and newly qualified health visitors, and on team relationships more broadly. To explore a 'community of learning hub' model in health visitor education and reflect on the role of space and place in the learning experience and professional identity development of student health visitors. Qualitative research conducted during first year of implementation. Three 'community of learning hub' projects based in two NHS community Trusts in London during the period 2013-2015. Managers and leads (n=7), practice teachers and mentors (n=6) and newly qualified and student health visitors (n=16). Semi-structured, audio-recorded interviews analysed thematically. Participants had differing views as to what constituted a 'hub' in their projects. Two themes emerged around the spaces that shape the learning experience of student and newly qualified health visitors. Firstly, a generalised need for a 'quiet place' which allows pause for reflection but also for sharing experiences and relieving common anxieties. Secondly, the role of physical arrangements in open-plan spaces to promote access to support from more experienced practitioners. Attention to spatiality can shed light on important aspects of teaching and learning practices, and on the professional identities these practices shape and support. New configurations of time and space as part of educational initiatives can surface new insights into existing practices and learning models. Copyright © 2017. Published by Elsevier Ltd.

  16. Human and Robotic Space Mission Use Cases for High-Performance Spaceflight Computing

    Science.gov (United States)

    Some, Raphael; Doyle, Richard; Bergman, Larry; Whitaker, William; Powell, Wesley; Johnson, Michael; Goforth, Montgomery; Lowry, Michael

    2013-01-01

    Spaceflight computing is a key resource in NASA space missions and a core determining factor of spacecraft capability, with ripple effects throughout the spacecraft, end-to-end system, and mission. Onboard computing can be aptly viewed as a "technology multiplier" in that advances provide direct dramatic improvements in flight functions and capabilities across the NASA mission classes, and enable new flight capabilities and mission scenarios, increasing science and exploration return. Space-qualified computing technology, however, has not advanced significantly in well over ten years and the current state of the practice fails to meet the near- to mid-term needs of NASA missions. Recognizing this gap, the NASA Game Changing Development Program (GCDP), under the auspices of the NASA Space Technology Mission Directorate, commissioned a study on space-based computing needs, looking out 15-20 years. The study resulted in a recommendation to pursue high-performance spaceflight computing (HPSC) for next-generation missions, and a decision to partner with the Air Force Research Lab (AFRL) in this development.

  17. Attention indicator dynamics of qualified climbers influenced by hypoxic training during the overcoming various altitude levels of Mount Elbrus

    Directory of Open Access Journals (Sweden)

    Andriy Kiyko

    2017-08-01

    Full Text Available Purpose: to determine the effect of hypoxic training on the attention indicators at different altitudes when crossing the Mount Elbrus. Material & Methods: the study of various attention indicators with the participation of control (n=16 and experimental (n=12 groups with the use of interval hypoxic training (IHT in the 15–15 mode with breathing through the system into a confined space in the experimental group and using the methods of mathematical statistics are carried out. Result: studies have made it possible to determine that the use of the regime of discontinuous hypoxia 15–15 in the training process of the pre-competitive period contribute to an increase in attention rates that affect adaptation to the load under hypoxia conditions. Conclusion: results of the conducted studies indicate that the use of IHT in the 15–15 mode in the period before the ascent to Mount Elbrus allows to significantly increase the attention rates of qualified climbers at different altitude levels.

  18. What Did They Take Away?: Examining Newly Qualified U.S. Teachers' Visions of Learning and Teaching Science in K-8 Classrooms

    Science.gov (United States)

    Roberts-Harris, Deborah

    2014-01-01

    This study investigated newly qualified K-8 teachers' visions of science learning and teaching after they had completed preparation in a science teaching methods course I taught. What visions of science learning and teaching were these newly qualified teachers taking away from my course? How did these visions compare with those advocated by reform…

  19. Design and implementation of robust decentralized control laws for the ACES structure at Marshall Space Flight Center

    Science.gov (United States)

    Collins, Emmanuel G., Jr.; Phillips, Douglas; Hyland, David C.

    1990-01-01

    An experiment was conducted to design controllers that would provide substantial reduction of line-of-sight control errors. The satisfaction of this objective required the controllers to attenuate the beam vibration significantly. Particular emphasis was placed on controller simplicity (i.e., reduced-order and decentralized controller architectures). Complexity reduction in control law implementation is of paramount interest due to stringent limitations on throughput of even state-of-the-art space qualified processors. The results of this experiment successfully demonstrate active vibrator control for a flexible structure. The testbed is the ACES structure at the NASA Marshall Space Flight Center. The ACES structure is dynamically traceable to future space systems and especially allows the study of line-of-sight control issues.

  20. 3 CFR - Medicare Demonstration To Test Medical Homes in Federally Qualified Health Centers

    Science.gov (United States)

    2010-01-01

    ... buy equipment, modernize clinic facilities, expand into new facilities, and adopt or expand the use of... interdisciplinary teams to treat the “whole patient” and focus on chronic disease management to reduce the use of costlier providers of care, such as emergency rooms and hospitals. Federally qualified health centers...

  1. The role of human-at-work systems in business sustainability: perspectives based on expert and qualified production workers in a manufacturing enterprise.

    Science.gov (United States)

    Genaidy, Ash M; Rinder, Maria M; Sequeira, Reynold; A-Rehim, Amal

    2010-04-01

    A community of highly qualified employees is desirable for the workforce to become a competitive business advantage, improving and sustaining corporate health. Currently, the scientific literature is limited on information comparing the assessment of expert and qualified workers for the employee-work environment interface. Such information would be valuable for industrial managers to obtain and act on the different perspectives of its workers for business improvement and survivability. A primary objective of this study is to explore the perspectives of expert and qualified workers on the quality of the employee-work environment interface in a manufacturing enterprise. This investigation was performed in a production department in a small manufacturing enterprise. Two expert workers participated in the study, with each being in the company for 30 years and having performed all jobs in the production department as well as supervisory and line management responsibilities. A total of 13 qualified workers from day and night shifts were used in the study, with the great majority of workers possessing 10 or more years of on-the-job experience but not acquiring the same specialised knowledge required for operating the technological resources in the department. The work compatibility methodology was used to assess the quality of employee-work environment interface for both expert and qualified workers. Both expert and qualified workers provided similar trends in terms of their compatibility assessment of experienced and acting work domains. In general, the compatibility levels for the day shift were poorer than those obtained for the night shift for acting work domains. The similarities in assessment between the expert and qualified workers were much closer for factors impacting job performance at the task and immediate surrounding levels (i.e. physical and mental task content, physical environment). There were greater differences at the macro level, that is, at the process

  2. [Cognitive emotion regulation of patients qualified for implantation of heart rhythm control device].

    Science.gov (United States)

    Ziętalewicz, Urszula; Jędrzejczyk, Jan; Mojkowski, Włodzimierz; Mojkowski, Dariusz

    2016-11-25

    The aim of the artificial heart stimulation is not only saving lives, but also improvement of the quality of life of patients with cardiac arrhythmias. One of the key dimensions of quality of life is psychological functioning. Until now, little research assess this dimension in patients before the implantation of the heart rhythm control device. The aim of the study was to assess the severity of depression and anxiety and the frequency of the used cognitive emotion regulation strategies and to examine the relationship between them. The study group consisted of 60 people qualified for pacemaker implantation (42 PM patients and 18 ICD): 15 women and 45 men ranging in age from 43 to 85. To assess cognitive emotion regulation strategies Cognitive Emotion Regulation Questionnaire was used, and to assess the severity of depression and anxiety - Mood Assessment Questionnaire. Patients with PM more often than patients with ICD use the strategy of Positive Reappraisal (U = 231.50, p = 0.045). There were no statistically significant differences in the frequency of use of other strategies and severity of depression and anxiety. In PM patients there are negative correlations between the severity of depression and anxiety and the use of Acceptance ( τ = -0.380), a Positive Reappraisal ( τ = -0.278), Positive Refocusing ( τ = -0.366) and between the level of anxiety and Putting into Perspective ( τ = -0.402). In ICD patients there was a positive relationship between anxiety and Cathastrophizing ( τ = 0.324). The severity of depression and anxiety, and emotion regulation strategies in patients qualified for PM implantation in comparison with patients qualified for ICD implantation are similar. Both groups of patients show a good adaptation of the psychological.

  3. Trademarks in the Linguistic Landscape: Methodological and Theoretical Challenges in Qualifying Brand Names in the Public Space

    Science.gov (United States)

    Tufi, Stefania; Blackwood, Robert

    2010-01-01

    In the last few decades, investigations into the linguistic landscape (LL) have sought to analyse written language practices as they are observable in public space. Whilst the LL analysis of language choice in given contexts has opened a host of possibilities for scientific enquiry in the field, the methodologies employed in the collection and…

  4. 40 CFR 60.2225 - What else must I report if I have a deviation from the requirement to have a qualified operator...

    Science.gov (United States)

    2010-07-01

    ... deviation from the requirement to have a qualified operator accessible? 60.2225 Section 60.2225 Protection... PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Commercial and Industrial Solid Waste... report if I have a deviation from the requirement to have a qualified operator accessible? (a) If all...

  5. Experimental study on the Stirling refrigerator for cooling of infrared detector

    Energy Technology Data Exchange (ETDEWEB)

    Park, S. J.; Hong, Y. J.; Kim, H. B.; Koh, D. Y. [Korea Institute of Machinery and Materials, Taejon (Korea, Republic of); Kim, J. H.; Yu, B. K. [Wooyoung, Seoul (Korea, Republic of)

    2001-07-01

    A Stirling cryocooler is relatively compact, reliable, commercially available, and uses helium as a working fluid. The FPFD Stirling cryocooler consists of two compressor pistons driven by linear motors which makes pressure waves and a pneumatically driven displacer piston with regenerator. A Free Piston and Free Displacer (FPFD) Stirling cryocooler for cooling infrared and cryo-sensors is currently under development at KIMM(Korea Institute of Machinery and Materials). In order to evaluate the feasibility of using a linear motor driving cryocooler, prototype Stirling cryocooler with a nominal cooling capacity of 0.5W at 80K was designed, fabricated and tested. The prototype has achieved no load temperature of 51K and cooling power of 0.33W.

  6. Experimental study on the Stirling refrigerator for cooling of infrared detector

    International Nuclear Information System (INIS)

    Park, S. J.; Hong, Y. J.; Kim, H. B.; Koh, D. Y.; Kim, J. H.; Yu, B. K.

    2001-01-01

    A Stirling cryocooler is relatively compact, reliable, commercially available, and uses helium as a working fluid. The FPFD Stirling cryocooler consists of two compressor pistons driven by linear motors which makes pressure waves and a pneumatically driven displacer piston with regenerator. A Free Piston and Free Displacer (FPFD) Stirling cryocooler for cooling infrared and cryo-sensors is currently under development at KIMM(Korea Institute of Machinery and Materials). In order to evaluate the feasibility of using a linear motor driving cryocooler, prototype Stirling cryocooler with a nominal cooling capacity of 0.5W at 80K was designed, fabricated and tested. The prototype has achieved no load temperature of 51K and cooling power of 0.33W

  7. Qualifying works of the Department of nuclear chemistry (1963 - 2006)

    International Nuclear Information System (INIS)

    Kuruc, J.

    2007-01-01

    In this review qualifying works (theses - bachelor, master, PhD., DrSc., habilitation and inauguration theses) elaborated at the Department of nuclear chemistry, Faculty of Natural Chemistry, Comenius University in Bratislava during forty years (from origin of the Section of Nuclear chemistry in 1963 up to 2006 are presented. During this time, in totally, 3 bachelor theses, 265 master theses, 24 PhD. (CSc.) and 10 PhD. dissertanions, 2 DrSc. dissertanions as well as 8 habilitation and one inauguration these were defended (author)

  8. Encounters of Newly Qualified Teachers with Micro-Politics in Primary Schools in Zimbabwe

    Science.gov (United States)

    Magudu, Snodia; Gumbo, Mishack

    2017-01-01

    This article demonstrates, through the example of Zimbabwe, the complexities of micro-political learning during induction. It reports on the experiences of ten newly qualified teachers with micro-politics or power relations in their schools during induction and locates these experiences within the broader context of their professional development.…

  9. Development, Qualification and Production of Space Solar Cells with 30% EOL Efficiency

    Science.gov (United States)

    Guter, Wolfgang; Ebel, Lars; Fuhrmann, Daniel; Kostler, Wolfgang; Meusel, Matthias

    2014-08-01

    AZUR SPACE's latest qualified solar cell product 3G30-advanced provides a high end-of-life (EOL) efficiency of 27.8% for 5E14 (1 MeV e-/cm2) at low production costs. In order to further reduce the mass, the 3G30-advanced was thinned down to as thin as 20 μm and tested in space. Next generation solar cells must exceed the EOL efficiency of the 3G30-advanced and therefore will utilize the excess current of the Ge subcell. This can be achieved by a metamorphic cell concept. While average beginning-of-life efficiencies above 31% have already been demonstrated with upright metamorphic triple-junction cells, AZUR's next generation product will comprise a metamorphic 4- junction device targeting 30% EOL.

  10. Generic requirements specification for qualifying a commercially available PLC for safety-related applications in nuclear power plants. Final report

    International Nuclear Information System (INIS)

    Ostenso, A.; May, R.

    1996-12-01

    This is a specification for qualifying a commercially available PLC for application to safety systems in nuclear power plants. The specifications are suitable for evaluating a particular PLC product line as a platform for safety-related applications, establishing a suitable qualification test program, and confirming that the manufacturer has a quality assurance program that is adequate for safety-related applications or is sufficiently complete that, with a reasonable set of compensatory actions, it can be brought into conformance. The specification includes requirements for: (1) quality assurance measures applied to the qualification activities, (2) documentation to support the qualification, and (3) documentation to provide the information needed for applying the qualified PLC platform to a specific application. The specifications are designed to encompass a broad range of safety applications; however, qualifying a particular platform for a different range of applications can be accomplished by appropriate adjustments to the requirements

  11. A comparison of ultra-endurance cyclists in a qualifying ultra-cycling race for Paris-Brest-Paris and Race Across America-Swiss cycling marathon.

    Science.gov (United States)

    Knechtle, Beat; Wirth, Andrea; Knechtle, Patrizia; Rüst, Christoph Alexander; Rosemann, Thomas

    2012-02-01

    Ultra-endurance events test the adaptation of human physiology to extreme physical and mental demands, high levels of training, motivation, and physical conditioning among participants. To understand basic differences among participants according to the severity of the race, participants in qualifying events for two ultra-endurance cycling races, differing in length and intensity, were compared on measures of anthropometry, training, and support. One race was four times longer, required supporting teams, and racers typically had little sleep, which should lead to the qualifiers being substantially more highly trained than those from the shorter race. The qualifiers in the longer race had greater intensity in training while the qualifiers in the shorter race relied more on training volume. Different strategies and types of training reflected the different demands of the races. Future studies should evaluate personality and motivational differences in ultra-endurance events and between these athletes and athletes in other sports.

  12. Status of an advanced radioisotope space power system using free-piston Stirling technology

    International Nuclear Information System (INIS)

    White, M.A.; Qiu, S.; Erbeznik, R.M.; Olan, R.W.; Welty, S.C.

    1998-01-01

    This paper describes a free-piston Stirling engine technology project to demonstrate a high efficiency power system capable of being further developed for deep space missions using a radioisotope (RI) heat source. The key objective is to develop a power system with an efficiency exceeding 20% that can function with a high degree of reliability for 10 years or longer on deep space missions. Primary issues being addressed for Stirling space power systems are weight and the vibration associated with reciprocating pistons. Similar weight and vibration issues have been successfully addressed with Stirling cryocoolers, which are the accepted standard for cryogenic cooling in space. Integrated long-life Stirling engine-generator (or convertor) operation has been demonstrated by the terrestrial Radioisotope Stirling Generator (RSG) and other Stirling Technology Company (STC) programs. Extensive RSG endurance testing includes more than 40,000 maintenance-free, degradation-free hours for the complete convertor, in addition to several critical component and subsystem endurance tests. The Stirling space power convertor project is being conducted by STC under DOE Contract, and NASA SBIR Phase II contracts. The DOE contract objective is to demonstrate a two-convertor module that represents half of a nominal 150-W(e) power system. Each convertor is referred to as a Technology Demonstration Convertor (TDC). The ultimate Stirling power system would be fueled by three general purpose heat source (GPHS) modules, and is projected to produce substantially more electric power than the 150-watt target. The system is capable of full power output with one failed convertor. One NASA contract, nearing completion, uses existing 350-W(e) RG-350 convertors to evaluate interactivity of two back-to-back balanced convertors with various degrees of electrical and mechanical interaction. This effort has recently provided the first successful synchronization of two convertors by means of parallel

  13. A 4-Kelvin Pulse-Tube/Reverse-Brayton Hybrid Cryocooler, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's ability to perform cutting edge space science, including lunar and planetary exploration, requires the use of cryogenically cooled detectors and sensors for...

  14. Miniature Turbine for Pulse-Tube/Reverse-Brayton Hybrid Cryocooler, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Many future advances in NASA's ability to perform cutting edge space science will require improvements in cryogenic system technology, including the development of...

  15. Influence of bodybuilding classes on physical qualities of the qualified sportswomen in different phases of the specific biological cycle

    Directory of Open Access Journals (Sweden)

    Vyacheslav Mulik

    2017-02-01

    Full Text Available Purpose: to conduct researches of influence of classes of the sportswomen who are going in for bodybuilding and fitness-bikini on manifestation of physical qualities in different phases of the ovarian-menstrual cycle. Material & Methods: researches were conducted in sports fitness-clubs of Kharkov "Feromon", "Gorod", “King” with the qualified sportswomen who are going in for bodybuilding and fitness-bikini within 3 months of the preparatory period in number of 14 people. We used as methods of the research: the analysis of references and testing of level of motive qualities in separate phases of OMC. Results: the theoretical analysis of features of the accounting of phases of OMC at sportswomen is submitted and the testing of the level of development of physical qualities in different phases of the specific biological cycle at the qualified sportswomen, who are going in for bodybuilding, is held. Conclusions: the received results demonstrate that physical efficiency of the qualified sportswomen, who are going in for bodybuilding, is not identical in phases of the ovarian-menstrual cycle. It is revealed that the best conditions for performance of considerable exercise stresses in post-ovulatory and post-menstrual phases of OMC, therefore it is expedient to plan them in the preparatory periods of the qualified sportswomen, who are going in for bodybuilding.

  16. IE Information Notice No. 85-82: Diesel generator differential protection relay not seismically qualified

    International Nuclear Information System (INIS)

    Jordan, E.L.

    1992-01-01

    Licensees of BWR and PWR nuclear generating stations have reported using a high-speed differential protection relay that has been declared by the manufacturer to be not seismically qualified for the service intended. The relay, GE Model 12CFD, which is being used for emergency diesel generator protection against electrical shorts and grounds at the generator output, has not been seismically qualified to operate in the de-energized state for this application. Generally, the relay operates in the de-energized position before EDG operation. However, it then operates in the energized position whenever the EDG provides an electrical output to essential Class IE components. The safety concern of this issue involves an inadvertent activation of the normally de-energized relay from a seismic event. Momentary activation of the relay, in the circuits examined, blocks the automatic start feature of the EDG during certain emergency plant conditions through operation of another relay in the system. The NRC review of the problems concluded that the relays should be seismically qualified in their energized and de-energized states to preclude their spurious activation during a seismic event. Additionally, review of GE's GER 3069 report, ''Relay Protection of Class IE Systems,'' shows that the 12CFD differential relays were successfully tested for 3.5 g in the energized modes and only 0.75 g in the de-energized mode. Review of GE's GER 3069 report also revealed that GE type IJD differential relays do meet seismic requirements in all modes of operation mentioned above and is the GE recommendation for replacement of the differential relay in question

  17. Hiring and keeping qualified personnel in a growing regulatory organisation

    International Nuclear Information System (INIS)

    Marchildon, P.

    1993-01-01

    Although no new nuclear stations are currently committed in Canada, the regulatory authority, the Atomic Energy Control Board (AECB), has started, in 1989, an expansion program which, when completed in 1994 will represent a 60 pc increase in its workforce. The new personnel resources are being used to improve the AECB effectiveness in a number of regulatory activities. This paper reviews some of the key factors which relate to the hiring and integration of the new AECB employees: selection process, timing, fees, scholarship program, subsequent training of qualified personnel, woman quotas. 2 figs

  18. Qualified equipment for spare parts and modifications in Belgium

    International Nuclear Information System (INIS)

    Berthe, J.

    1993-01-01

    This paper describes the procedure followed for the procurement of components for spare parts and systems modifications, the legal and quality assurance environment and the specific measures taken to cope with various codes and standards. For pressure components, the regulation aspects of the American code used during the construction phase of plants had to be adapted to the Belgian context and to the actual industry situation. Obsolescence of products is treated either by qualification of a new product or by design modifications, or by replacement with an already qualified product. In these cases, the work is handled by the utility's engineering organization. 2 figs

  19. 13 CFR 126.613 - How does a price evaluation preference affect the bid of a qualified HUBZone SBC in full and open...

    Science.gov (United States)

    2010-01-01

    ... full and open competition, a qualified HUBZone SBC submits an offer of $98, a non-HUBZone SBC submits..., the non-HUBZone SBC's offer at $100 does not displace the large business' offer because a price... and open competition, a qualified HUBZone SBC submits an offer of $98 and a non-HUBZone SBC submits an...

  20. Nutritional status assessment in colorectal cancer patients qualified to systemic treatment

    OpenAIRE

    Ziętarska, Monika; Krawczyk-Lipiec, Joanna; Kraj, Leszek; Zaucha, Renata; Małgorzewicz, Sylwia

    2017-01-01

    Aim of the study Cancer is usually associated with impaired nutritional status, which is one of the factors contributing to the deterioration of the results of surgery, chemotherapy, or radiotherapy. The aim of this study was the assessment of the nutritional status of patients with CRC qualified to chemotherapy. Material and methods Seventy-five persons aged 40–86 years with colorectal cancer were examined. To evaluate the nutritional status NRS 2002, SGA, SCRINIO Working Group classificatio...