Physical Training Strategies for Military Women's Performance Optimization in Combat-Centric Occupations.

Science.gov (United States)

Nindl, Bradley C

2015-11-01

The physiological differences, particularly of upper-body strength and power, between women and men, and the rigors of combat-centric occupational demands would seem to place women at a significant disadvantage, as the U.S. military opens up previously closed combat-arms military occupational specialties (MOSs) to women. This inherent disadvantage can be significantly mitigated by implementing effective and comprehensive physical training (PT) regimens for women targeting those fitness components most critical for those tasks considered most essential for solider warfighting duties (i.e., strength and power). Regrettably, the military historical and legacy overemphasis on aerobic fitness and on "field expediency" as the major criteria for implementing training have limited the extent to which the military has fully operationalized state-of-the-science PT policies. This continued legacy approach could be problematic regarding fully enhancing women's abilities to perform physically demanding combat-centric occupations and could place the successful integration of women into ground combat MOSs at significant risk. Seminal studies from the literature indicate that (a) a minimum of 6 months of periodized combined resistance/endurance training preparedness is recommended for untrained women considering entering combat-arms MOS training; (b) any comprehensive PT program should incorporate and emphasize progressive load carriage training; (c) a greater emphasis on upper body on strength/power development in military women is needed; (d) heavy resistance training in the range of 3-8 repetition maximum sets should be incorporated into training programs to target type II motor units and muscle fibers (those fibers that produce the most force and have the greatest capacity to hypertrophy); (e) low-volume, high-intensity interval training should be considered as a time-efficient training method to improve aerobic fitness while protecting against lower-body musculoskeletal

Fabrication of advanced military radiation detector sensor and performance evaluation

Energy Technology Data Exchange (ETDEWEB)

Kang, Sin Yang

2010-02-15

efficiency: 41%). This alpha - particle sensor shows a performance comparable to commercial ones. The beta ray sensor was manufactured using a BC-408 organic plastic scintillator. The main goal of this study was the measurement of beta - ray responses of the PMMA light guide attached to the sensor and the determination of window materials. Finally, the CsI(Tl) scintillator gamma ray sensor manufactured as engineering model and the shielding case was made of duralumin (side plane) and aluminium (window). The performance of the gamma - ray sensor was comparable to commercial high - sensitivity industrial sensors. These three types of scintillation sensors can be used directly as military equipment. And this study helps improving the protection of our country from nuclear threats

Thermal Cameras and Applications

DEFF Research Database (Denmark)

Gade, Rikke; Moeslund, Thomas B.

2014-01-01

Thermal cameras are passive sensors that capture the infrared radiation emitted by all objects with a temperature above absolute zero. This type of camera was originally developed as a surveillance and night vision tool for the military, but recently the price has dropped, significantly opening up...... a broader field of applications. Deploying this type of sensor in vision systems eliminates the illumination problems of normal greyscale and RGB cameras. This survey provides an overview of the current applications of thermal cameras. Applications include animals, agriculture, buildings, gas detection......, industrial, and military applications, as well as detection, tracking, and recognition of humans. Moreover, this survey describes the nature of thermal radiation and the technology of thermal cameras....

Thermal performance and heat transport in aquifer thermal energy storage

Science.gov (United States)

Sommer, W. T.; Doornenbal, P. J.; Drijver, B. C.; van Gaans, P. F. M.; Leusbrock, I.; Grotenhuis, J. T. C.; Rijnaarts, H. H. M.

2014-01-01

Aquifer thermal energy storage (ATES) is used for seasonal storage of large quantities of thermal energy. Due to the increasing demand for sustainable energy, the number of ATES systems has increased rapidly, which has raised questions on the effect of ATES systems on their surroundings as well as their thermal performance. Furthermore, the increasing density of systems generates concern regarding thermal interference between the wells of one system and between neighboring systems. An assessment is made of (1) the thermal storage performance, and (2) the heat transport around the wells of an existing ATES system in the Netherlands. Reconstruction of flow rates and injection and extraction temperatures from hourly logs of operational data from 2005 to 2012 show that the average thermal recovery is 82 % for cold storage and 68 % for heat storage. Subsurface heat transport is monitored using distributed temperature sensing. Although the measurements reveal unequal distribution of flow rate over different parts of the well screen and preferential flow due to aquifer heterogeneity, sufficient well spacing has avoided thermal interference. However, oversizing of well spacing may limit the number of systems that can be realized in an area and lower the potential of ATES.

The Effect of Military Coup and Interventions on the Economic Performance: The Case of Turkey

Directory of Open Access Journals (Sweden)

Arif ÖZSAĞIR

2013-12-01

Full Text Available Some factors that affect the economic life indirectly but substantially at the same time are assumed exogenous or fixed by the traditional economics. However, these factors are considered fixed are the factors that affect the economy deeply. Political stability, verdicts devoid of justice, military coups and interventions, oligarchical bureaucratic structure, and terrorism are important factors assumed to be fixed. Although these factors may seem irrelevant at first glance, they have crucial impacts on economies. Important determinants of Turkey’s economic performance have been political decisions, the verdicts devoid of justice, in other words biased verdicts, military coups and interventions, oligarchical bureaucratic structure, and terrorism rather than economic policies. In this study, it is discussed that the effects of military coups and interventions on the performance of the economy in the context of Turkey example; and the hypothesis is validated within the framework of an econometric model.

Thermal Performance Benchmarking: Annual Report

Energy Technology Data Exchange (ETDEWEB)

Feng, Xuhui [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Transportation and Hydrogen Systems Center

2017-10-19

In FY16, the thermal performance of the 2014 Honda Accord Hybrid power electronics thermal management systems were benchmarked. Both experiments and numerical simulation were utilized to thoroughly study the thermal resistances and temperature distribution in the power module. Experimental results obtained from the water-ethylene glycol tests provided the junction-to-liquid thermal resistance. The finite element analysis (FEA) and computational fluid dynamics (CFD) models were found to yield a good match with experimental results. Both experimental and modeling results demonstrate that the passive stack is the dominant thermal resistance for both the motor and power electronics systems. The 2014 Accord power electronics systems yield steady-state thermal resistance values around 42- 50 mm to the 2nd power K/W, depending on the flow rates. At a typical flow rate of 10 liters per minute, the thermal resistance of the Accord system was found to be about 44 percent lower than that of the 2012 Nissan LEAF system that was benchmarked in FY15. The main reason for the difference is that the Accord power module used a metalized-ceramic substrate and eliminated the thermal interface material layers. FEA models were developed to study the transient performance of 2012 Nissan LEAF, 2014 Accord, and two other systems that feature conventional power module designs. The simulation results indicate that the 2012 LEAF power module has lowest thermal impedance at a time scale less than one second. This is probably due to moving low thermally conductive materials further away from the heat source and enhancing the heat spreading effect from the copper-molybdenum plate close to the insulated gate bipolar transistors. When approaching steady state, the Honda system shows lower thermal impedance. Measurement results of the thermal resistance of the 2015 BMW i3 power electronic system indicate that the i3 insulated gate bipolar transistor module has significantly lower junction

Cadmium-emitter self-powered thermal neutron detector performance characterization & reactor power tracking capability experiments performed in ZED-2

Energy Technology Data Exchange (ETDEWEB)

LaFontaine, M.W., E-mail: physics@execulink.com [LaFontaine Consulting, Kitchener, Ontario (Canada); Zeller, M.B. [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Nielsen, K. [Royal Military College of Canada, SLOWPOKE-2 Reactor, Kingston, Ontario (Canada)

2014-07-01

Cadmium-emitter self-powered thermal neutron flux detectors (SPDs), are typically used for flux monitoring and control applications in low temperature, test reactors such as the SLOWPOKE-2. A collaborative program between Atomic Energy of Canada, academia (Royal Military College of Canada (RMCC)) and industry (LaFontaine Consulting) was initiated to characterize the incore performance of a typical Cd-emitter SPD; and to obtain a definitive measure of the capability of the detector to track changes in reactor power in real time. Prior to starting the experiment proper, Chalk River Laboratories' ZED-2 was operated at low power (5 watts nominal) to verify the predicted moderator critical height. Test measurements were then performed with the vertical center of the SPD emitter positioned at the vertical mid-plane of the ZED-2 reactor core. Measurements were taken with the SPD located at lattice position L0 (near center), and repeated at lattice position P0 (in D{sub 2}O reflector). An ionization chamber (part of the ZED-2 control instrumentation) monitored reactor power at a position located on the south side of the outside wall of the reactor's calandria. These experiments facilitated measurement of the absolute thermal neutron sensitivity of the subject Cd-emitter SPD, and validated the power tracking capability of said SPD. Procedural details of the experiments, data, calculations and associated graphs, are presented and discussed. (author)

High-G Thermal Characterization Centrifuge

Data.gov (United States)

Federal Laboratory Consortium — High-G testing of thermal components enables improved understanding of operating behavior under military-relevant environments. The High-G Thermal Characterization...

MHTGR thermal performance envelopes: Reliability by design

International Nuclear Information System (INIS)

Etzel, K.T.; Howard, W.W.; Zgliczynski, J.B.

1992-05-01

This document discusses thermal performance envelopes which are used to specify steady-state design requirements for the systems of the Modular High Temperature Gas-Cooled Reactor to maximize plant performance reliability with optimized design. The thermal performance envelopes are constructed around the expected operating point accounting for uncertainties in actual plant as-built parameters and plant operation. The components are then designed to perform successfully at all points within the envelope. As a result, plant reliability is maximized by accounting for component thermal performance variation in the design. The design is optimized by providing a means to determine required margins in a disciplined and visible fashion

Exploring military performance motivation from an African Ubuntu perspective

CSIR Research Space (South Africa)

Van Heerden, Adelai

2017-09-01

Full Text Available The purpose of this study was to use a Positive Psychology lens to explore the perceptions of elite military candidates about motivational strategies that assisted them to cope with the challenges of specialized military selection. Results from our...

Thermal performance advisor expert system development

International Nuclear Information System (INIS)

McClintock, M.; Hirota, N.; Metzinger, R.

1991-01-01

In recent years the electric industry has developed an increased interest in improving efficiency of nuclear power plants. EPRI has embarked upon a research project RP2407, Nuclear Plant Performance Improvements which is designed to address needs in this area. One product of this project has been the Thermal Performance Diagnostic Manual for Nuclear Power Plants (NP-4990P). The purpose of this manual is to provide engineering personnel at nuclear power plants with a consistent way in which to identify thermal performance problems. General Physics is also involved in the development of another computer system called Fossil Thermal Performance Advisor (FTPA) which helps operators improve performance for fossil power plants. FTPA is a joint venture between General Physics and New York State Electric and Gas Company. This paper describes both of these computer systems and uses the FTPA as an interesting comparison that illustrates the considerations required for the development of a computer system that effectively addresses the needs of the users

Common display performance requirements for military and commercial aircraft product lines

Science.gov (United States)

Hoener, Steven J.; Behrens, Arthur J.; Flint, John R.; Jacobsen, Alan R.

2001-09-01

Obtaining high quality Active Matrix Liquid Crystal (AMLCD) glass to meet the needs of the commercial and military aerospace business is a major challenge, at best. With the demise of all domestic sources of AMLCD substrate glass, the industry is now focused on overseas sources, which are primarily producing glass for consumer electronics. Previous experience with ruggedizing commercial glass leads to the expectation that the aerospace industry can leverage off the commercial market. The problem remains, while the commercial industry is continually changing and improving its products, the commercial and military aerospace industries require stable and affordable supplies of AMLCD glass for upwards of 20 years to support production and maintenance operations. The Boeing Engineering and Supplier Management Process Councils have chartered a group of displays experts from multiple aircraft product divisions within the Boeing Company, the Displays Process Action Team (DPAT), to address this situation from an overall corporate perspective. The DPAT has formulated a set of Common Displays Performance Requirements for use across the corporate line of commercial and military aircraft products. Though focused on the AMLCD problem, the proposed common requirements are largely independent of display technology. This paper describes the strategy being pursued within the Boeing Company to address the AMLCD supply problem and details the proposed implementation process, centered on common requirements for both commercial and military aircraft displays. Highlighted in this paper are proposed common, or standard, display sizes and the other major requirements established by the DPAT, along with the rationale for these requirements.

Thermal performance of a PCM thermal storage unit

Energy Technology Data Exchange (ETDEWEB)

Liu Ming; Bruno, Frank; Saman, Wasim [Sustainable Energy Centre, Inst. for Sustainable Systems and Technologies, Univ. of South Australia, Mawson Lakes, Adelaide (Australia)

2008-07-01

The thermal performance of a PCM thermal storage unit (TSU) is studied numerically and experimentally. The TSU under analysis consists of several flat slabs of phase change material (PCM) with melting temperature of -26.7 C. Liquid heat transfer fluid (HTF) passes between the slabs to charge and discharge the storage unit. A one dimensional mathematical model was employed to analyze the transient thermal behavior of the storage unit during the melting and freezing processes. The model takes into consideration the temperature variations in the wall along the flow direction of the HTF. The paper compares the experimental and numerical simulation results in terms of HTF outlet temperatures during the melting period. (orig.)

Performance Indexing: Assessing the Nonmonetized Returns on Investment in Military Equipment

Science.gov (United States)

2016-05-17

Image designed by Diane Fleischer PERFORMANCE INDEXING: Assessing the NONMONETIZED RETURNS ON INVESTMENT in Military Equipment Ian D...MacLeod and Capt Robert A. Dinwoodie, USMC A prime managerial concern is how to decide which investment alternatives provide the greatest return with...agencies, these methods often fall short because typical governmental investments do not have a monetary return. The processes underpinning governmental

32 CFR 1630.48 - Class 4-A-A: Registrant who has performed military service for a foreign nation.

Science.gov (United States)

2010-07-01

... military service for a foreign nation. 1630.48 Section 1630.48 National Defense Other Regulations Relating... who has performed military service for a foreign nation. In Class 4-A-A shall be placed any registrant... be written in the English language. [52 FR 24456, July 1, 1987] ...

Investigation of the energy efficiency of the military museum building by infrared thermography

Directory of Open Access Journals (Sweden)

Slavica S. Ristić

2013-06-01

Full Text Available Infrared (IR thermography, as a diagnostic technique, is used to find anomalies in the thermal signature of the Military museum building in Belgrade, to identify irregularities or deficiencies, such as wet materials, voids, or missing insulation and to inspect energy efficiency of the museum building and microclimatic indoor conditions.  It is very important to perform preventative maintenance and stop undesirable environment influences that induce structural damage, modification of materials and agglomeration of pollutants and microorganisms on the cultural heritage artifacts, stored in the museum depot or exhibited in the galleries. The main causes for corrosion in historical buildings and museum artifacts are moisture and changeable temperature conditions. This paper deals with the results obtained in the application of IR thermography in determination of these conditions in the Military museum building, where very important metal artifacts are exhibited and deposed. The results show poor thermal insulation, wet walls and, generally, low energy efficiency.

High-performance noncontact thermal diode via asymmetric nanostructures

Science.gov (United States)

Shen, Jiadong; Liu, Xianglei; He, Huan; Wu, Weitao; Liu, Baoan

2018-05-01

Electric diodes, though laying the foundation of modern electronics and information processing industries, suffer from ineffectiveness and even failure at high temperatures. Thermal diodes are promising alternatives to relieve above limitations, but usually possess low rectification ratios, and how to obtain a high-performance thermal rectification effect is still an open question. This paper proposes an efficient contactless thermal diode based on the near-field thermal radiation of asymmetric doped silicon nanostructures. The rectification ratio computed via exact scattering theories is demonstrated to be as high as 10 at a nanoscale gap distance and period, outperforming the counterpart flat-plate diode by more than one order of magnitude. This extraordinary performance mainly lies in the higher forward and lower reverse radiative heat flux within the low frequency band compared with the counterpart flat-plate diode, which is caused by a lower loss and smaller cut-off wavevector of nanostructures for the forward and reversed scheme, respectively. This work opens new routes to realize high performance thermal diodes, and may have wide applications in efficient thermal computing, thermal information processing, and thermal management.

Thermal and metabolic responses of military divers during a 6-hour static dive in cold water.

Science.gov (United States)

Riera, Florence; Horr, Reed; Xu, Xiaojiang; Melin, Bruno; Regnard, Jacques; Bourdon, Lionel

2014-05-01

Human thermal responses during prolonged whole-body immersion in cold water are of interest for the military, especially French SEALS. This study aims at describing the thermo-physiological responses. There were 10 male military divers who were randomly assigned to a full immersion in neutral (34 degrees C), moderately cold (18 degrees C), and cold (10 degrees C) water wearing their operational protective devices (5.5 mm wetsuit with 3.0 mm thick underwear) for 6 h in a static position. Rectal temperature (T(re)) and 14 skin temperatures (T(sk)), blood analysis (stress biomarkers, metabolic substrates), and oxygen consumption (Vo2) were collected. At 34 degrees C, there were no significant modifications of the thermo-physiological responses over time. The most interesting result was that rates of rectal temperature decrease (0.15 +/- 0.02 degrees C x min(-1)) were the same between the two cold stress experimental conditions (at 18 degrees C and 10 degrees C). At the final experiment, rectal temperature was not significantly different between the two cold stress experimental conditions. Mean T(sk) decreased significantly during the first 3 h of immersion and then stabilized at a lower level at 10 degrees C (25.6 +/- 0.8 degrees C) than at 18 degrees C (29.3 +/- 0.9 degrees C). Other results demonstrate that the well-trained subjects developed effective physiological reactions. However, these reactions are consistently too low to counterbalance the heat losses induced by cold temperature conditions and long-duration immersion. This study shows that providing divers with thermal protection is efficient for a long-duration immersion from a medical point of view, but not from an operational one when skin extremities were taken into account.

Body mass index predicts selected physical fitness attributes but is not associated with performance on military relevant tasks in U.S. Army Soldiers.

Science.gov (United States)

Pierce, Joseph R; DeGroot, David W; Grier, Tyson L; Hauret, Keith G; Nindl, Bradley C; East, Whitfield B; McGurk, Michael S; Jones, Bruce H

2017-11-01

Army body composition standards are based upon validated criteria; however, certain field-expedient methodologies (e.g., weight-for-height, body mass index [BMI]) may disqualify individuals from service who may otherwise excel on physical performance and military-relevant tasks. The purpose was to assess soldier physical performance and military-specific task/fitness performance stratified by BMI. Cross-sectional observational study. Male (n=275) and female (n=46) soldiers performed a wide-array of physical fitness tests and military-specific tasks, including the Army physical fitness test (APFT). Within-sex performance data were analyzed by BMI tertile stratification or by Army Body Composition Program (ABCP) weight-for-height (calculated BMI) screening standards using ANOVA/Tukey post-hoc or independent t-tests, respectively. BMI stratification (higher vs. lower BMI) was associated with significant improvements in muscular strength and power, but also with decrements in speed/agility in male and female soldiers. Within the military specific tasks, a higher BMI was associated with an increased APFT 2-Mile Run time; however, performance on a 1600-m Loaded March or a Warrior Task and Battle Drill obstacle course was not related to BMI in either sex. Male and Female soldiers who did not meet ABCP screening standards demonstrated a slower 2-Mile Run time; however, not meeting the ABCP BMI standard only affected a minimal number (∼6%) of soldiers' ability to pass the APFT. Military body composition standards require a careful balance between physical performance, health, and military readiness. Allowances should be considered where tradeoffs exist between body composition classifications and performance on physical tasks with high military relevance. Published by Elsevier Ltd.

British Military surgical key performance indicators: time for an update?

Science.gov (United States)

Marsden, Max Er; Sharrock, A E; Hansen, C L; Newton, N J; Bowley, D M; Midwinter, M

2016-10-01

Key performance indicators (KPIs) are metrics that compare actual care against an ideal structure, process or outcome standard. KPIs designed to assess performance in deployed military surgical facilities have previously been published. This study aimed to review the overall performance of surgical trauma care for casualties treated at Role 3 Camp Bastion, Medical Treatment Facility, Afghanistan, in light of the existing Defence Medical Services (DMS) KPIs. The secondary aims were to assess the utility of the surgical KPIs and make recommendations for future surgical trauma care review. Data on 22 surgical parameters were prospectively collected for 150 injured patients who had primary surgery at Camp Bastion between 1 May 2013 and 20 August 2013. Additional information for these patients was obtained using the Joint Theatre Trauma Register. The authors assessed data recording, applicability and compliance with the KPIs. Median data recording was 100% (IQR 98%-100%), median applicability was 56% (IQR 10%-99%) and median compliance was 78% (IQR 58%-93%). One KPI was not applicable to any patient in our population. Eleven KPIs achieved >80% compliance, five KPIs had 80%-60% compliance and five KPIs had performance of the surgical aspect of military trauma care in 2013. The KPIs highlight areas for improvement in service delivery. Individual KPI development should be driven by evidence and reflect advances in practice and knowledge. A method of stakeholder consultation, and sequential refinement following evidence review, may be the right process to develop the future set of DMS KPIs. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Optical Thermal Characterization Enables High-Performance Electronics Applications

Energy Technology Data Exchange (ETDEWEB)

2016-02-01

NREL developed a modeling and experimental strategy to characterize thermal performance of materials. The technique provides critical data on thermal properties with relevance for electronics packaging applications. Thermal contact resistance and bulk thermal conductivity were characterized for new high-performance materials such as thermoplastics, boron-nitride nanosheets, copper nanowires, and atomically bonded layers. The technique is an important tool for developing designs and materials that enable power electronics packaging with small footprint, high power density, and low cost for numerous applications.

Cardboard Based Packaging Materials as Renewable Thermal Insulation of Buildings: Thermal and Life Cycle Performance

OpenAIRE

Čekon, Miroslav; Struhala, Karel; Slávik, Richard

2017-01-01

Cardboard based packaging components represent a material with a significant potential of renewable exploitation in buildings. This study presents the results of thermal and environmental analysis of existing packaging materials compared with standard conventional thermal insulations. Experimental measurements were performed to identify the thermal performance of studied cardboard packaging materials. Real-size samples were experimentally tested in laboratory measurements. The thermal resi...

Application of military uncooled infrared sensors to homeland defense

Science.gov (United States)

Hornberger, Chris

2002-08-01

During the early 1990's, uncooled microbolometer thermal imaging technology began a journey from Government and corporate laboratories to practical application in addressing military, Government, and commercial customer needs. Today, that transition could arguably be considered complete, punctuated by BAE SYSTEMS' delivery of the 10,000th microbolometer camera on 12 February 2002. While microbolometer developmental research continues to advance the state-of-the-art at an ever increasing pace, uncooled infrared cameras are widely deployed serving society in meaningful ways; from preventative maintenance and process inspection to law enforcement and rescue operations. Following last years terrorist attacks in New York and Virginia, President Bush appointed Governor Ridge to lead federal coordination efforts for defense of the homeland. While uncooled microbolometer sensors served in Homeland Security long before September 2001, it is certain that new applications will be identified for surveillance, security, law enforcement and protection needs. In this paper we will describe advances in military uncooled infrared sensor technology and how these sensors can serve in the role of Homeland Defense. Developments in uncooled sensors that will be described include the rugged performance validation of a thermal weapon sight and head-mounted imager. We will look at those areas of Homeland Defense that are most likely to benefit from the application of uncooled microbolometer thermal imaging sensor technology. These include: a) search & rescue camera systems, b) handheld surveillance systems and c) hands-free camera systems.

DARPA Workshop on Geothermal Energy for Military Operations

Science.gov (United States)

2010-05-01

is administered by its Geothermal Program Office (GPO) at the Navy Air Weapons Station, China Lake, CA. GPO manages the Coso Geo- thermal Field at...advanced geothermal technologies might reduce the risk and cost to the point where the U.S. military would be able to take advantage. Supplying geothermal...was con- vened to explore whether investment in advanced geothermal technologies might reduce the risk and cost to the point where the U.S. military

Natural selection on thermal preference, critical thermal maxima and locomotor performance.

Science.gov (United States)

Gilbert, Anthony L; Miles, Donald B

2017-08-16

Climate change is resulting in a radical transformation of the thermal quality of habitats across the globe. Whereas species have altered their distributions to cope with changing environments, the evidence for adaptation in response to rising temperatures is limited. However, to determine the potential of adaptation in response to thermal variation, we need estimates of the magnitude and direction of natural selection on traits that are assumed to increase persistence in warmer environments. Most inferences regarding physiological adaptation are based on interspecific analyses, and those of selection on thermal traits are scarce. Here, we estimate natural selection on major thermal traits used to assess the vulnerability of ectothermic organisms to altered thermal niches. We detected significant directional selection favouring lizards with higher thermal preferences and faster sprint performance at their optimal temperature. Our analyses also revealed correlational selection between thermal preference and critical thermal maxima, where individuals that preferred warmer body temperatures with cooler critical thermal maxima were favoured by selection. Recent published estimates of heritability for thermal traits suggest that, in concert with the strong selective pressures we demonstrate here, evolutionary adaptation may promote long-term persistence of ectotherms in altered thermal environments. © 2017 The Author(s).

Thermal performance of nanofluid flow in microchannels

Energy Technology Data Exchange (ETDEWEB)

Li Jie [Department of Mechanical and Aerospace Engineering, University of North Carolina, Campus Box 7910, Broungton Hall 4160, Raleigh, NC 27695-7910 (United States); Kleinstreuer, Clement [Department of Mechanical and Aerospace Engineering, University of North Carolina, Campus Box 7910, Broungton Hall 4160, Raleigh, NC 27695-7910 (United States)], E-mail: ck@eos.ncsu.edu

2008-08-15

Two effective thermal conductivity models for nanofluids were compared in detail, where the new KKL (Koo-Kleinstreuer-Li) model, based on Brownian motion induced micro-mixing, achieved good agreements with the currently available experimental data sets. Employing the commercial Navier-Stokes solver CFX-10 (Ansys Inc., Canonsburg, PA) and user-supplied pre- and post-processing software, the thermal performance of nanofluid flow in a trapezoidal microchannel was analyzed using pure water as well as a nanofluid, i.e., CuO-water, with volume fractions of 1% and 4% CuO-particles with d{sub p} = 28.6 nm. The results show that nanofluids do measurably enhance the thermal performance of microchannel mixture flow with a small increase in pumping power. Specifically, the thermal performance increases with volume fraction; but, the extra pressure drop, or pumping power, will somewhat decrease the beneficial effects. Microchannel heat sinks with nanofluids are expected to be good candidates for the next generation of cooling devices.

Selling petroleum to the military

International Nuclear Information System (INIS)

Uscher, R.H.

1999-01-01

This article examines what petroleum products and services the US military buys, the contracts awarded to Asian and European refiners for supplies outside the USA, and military specifications and test methods including the specifications of JP-8 battlefield fuel and the JP-8+100 additive package for military aircraft. The way in which the military buys petroleum products is described, and details are given of the types of military contracts, the bidding on Defense Energy Support Center (DESC) petroleum contracts, the performance of military petroleum contracts, socio-economic programmes, the Prompt Payment Act requiring contractors to be paid promptly, and procedures for claims and disputes

Development of thermal stability additive packages for JP-8

Energy Technology Data Exchange (ETDEWEB)

Anderson, S.D.; Harrison, W.E. III; Edwards, T.; Morris, R.W.; Shouse, D.T. [USAF Wright Lab., Wright-Paterson AFB, OH (United States)

1995-05-01

Advanced military aircraft use fuel as the primary heat sink to cool engine and airframe components. As the fuel is thermally stressed, thermal oxidative reactions take place that result in the formation of deposits. These deposits degrade aircraft performance and ultimately lead to premature servicing of the affected components. The frequency of these incidents, coupled with the projected cooling requirements for future systems, demonstrates that current thermal stability limits are inadequate. In response to this situation, the United States Air Force (USAF) has embarked on a program to improve thermal stability using specially formulated additive packages. Results indicate that additives offer significant thermal stability improvement. This paper describes the USAF program to develop and deploy an improved JP-8 for fleet-wide use by 1998.

31 CFR 29.333 - Military service.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Military service. 29.333 Section 29... Satisfied by June 30, 1997 § 29.333 Military service. (a) For employees who entered on duty on or before June 30, 1997, and whose military service was performed prior to that date, credit for military service...

Temperature Distribution and Thermal Performance of an Aquifer Thermal Energy Storage System

Science.gov (United States)

Ganguly, Sayantan

2017-04-01

Energy conservation and storage has become very crucial to make use of excess energy during times of future demand. Excess thermal energy can be captured and stored in aquifers and this technique is termed as Aquifer Thermal Energy Storage (ATES). Storing seasonal thermal energy in water by injecting it into subsurface and extracting in time of demand is the principle of an ATES system. Using ATES systems leads to energy savings, reduces the dependency on fossil fuels and thus leads to reduction in greenhouse gas emission. This study numerically models an ATES system to store seasonal thermal energy and evaluates the performance of it. A 3D thermo-hydrogeological numerical model for a confined ATES system is presented in this study. The model includes heat transport processes of advection, conduction and heat loss to confining rock media. The model also takes into account regional groundwater flow in the aquifer, geothermal gradient and anisotropy in the aquifer. Results show that thermal injection into the aquifer results in the generation of a thermal-front which grows in size with time. Premature thermal-breakthrough causes thermal interference in the system when the thermal-front reaches the production well and consequences in the fall of system performance and hence should be avoided. This study models the transient temperature distribution in the aquifer for different flow and geological conditions. This may be effectively used in designing an efficient ATES project by ensuring safety from thermal-breakthrough while catering to the energy demand. Based on the model results a safe well spacing is proposed. The thermal energy discharged by the system is determined and strategy to avoid the premature thermal-breakthrough in critical cases is discussed. The present numerical model is applied to simulate an experimental field study which is found to approximate the field results quite well.

Military exceptionalism or tobacco exceptionalism: How civilian health leaders' beliefs may impede military tobacco control efforts

OpenAIRE

Smith, EA; Malone, RE

2013-01-01

Smoking impairs the readiness and performance of military personnel, yet congressional opposition has thwarted military tobacco control initiatives. Involvement of civilian organizations might alter this political dynamic. We interviewed 13 leaders of national civilian public health and tobacco control organizations to explore their perspectives on military tobacco control, inductively analyzing data for themes. Leaders believed that military tobacco use was problematic but lacked specific kn...

Thermal performance measurements on ATLAS-SCT KB forward modules

CERN Document Server

Donegà, M; D'Onofrio, M; Ferrère, D; Hirt, C; Ikegami, Y; Kohriki, T; Kondo, T; Lindsay, S; Mangin-Brinet, M; Niinikoski, T O; Pernegger, H; Perrin, E; Taylor, G; Terada, S; Unno, Y; Wallny, R; Weber, M

2003-01-01

The thermal design of the KB module is presented. A Finite Elements Analysis (FEA) has been used to finalize the module design. The thermal performance of an outer irradiated KB module has been measured at different cooling conditions. The thermal runaway of the module has been measured. The FEA model has been compared with the measurements and has been used to predict the thermal performance in a realistic SCT scenario.

Effect of thermal state and thermal comfort on cycling performance in the heat.

Science.gov (United States)

Schulze, Emiel; Daanen, Hein A M; Levels, Koen; Casadio, Julia R; Plews, Daniel J; Kilding, Andrew E; Siegel, Rodney; Laursen, Paul B

2015-07-01

To determine the effect of thermal state and thermal comfort on cycling performance in the heat. Seven well-trained male triathletes completed 3 performance trials consisting of 60 min cycling at a fixed rating of perceived exertion (14) followed immediately by a 20-km time trial in hot (30°C) and humid (80% relative humidity) conditions. In a randomized order, cyclists either drank ambient-temperature (30°C) fluid ad libitum during exercise (CON), drank ice slurry (-1°C) ad libitum during exercise (ICE), or precooled with iced towels and ice slurry ingestion (15 g/kg) before drinking ice slurry ad libitum during exercise (PC+ICE). Power output, rectal temperature, and ratings of thermal comfort were measured. Overall mean power output was possibly higher in ICE (+1.4%±1.8% [90% confidence limit]; 0.4> smallest worthwhile change [SWC]) and likely higher PC+ICE (+2.5%±1.9%; 1.5>SWC) than in CON; however, no substantial differences were shown between PC+ICE and ICE (unclear). Time-trial performance was likely enhanced in ICE compared with CON (+2.4%±2.7%; 1.4>SWC) and PC+ICE (+2.9%±3.2%; 1.9>SWC). Differences in mean rectal temperature during exercise were unclear between trials. Ratings of thermal comfort were likely and very likely lower during exercise in ICE and PC+ICE, respectively, than in CON. While PC+ICE had a stronger effect on mean power output compared with CON than ICE did, the ICE strategy enhanced late-stage time-trial performance the most. Findings suggest that thermal comfort may be as important as thermal state for maximizing performance in the heat.

Bringing the Military Back in: Military Expenditures and Economic Growth 1990 to 2003

Directory of Open Access Journals (Sweden)

Jeffrey Kentor

2015-08-01

Full Text Available After the “peace bonus” era, global military expenditures have escalated sharply despite some worldwide declines in military personnel. Theories on the economic impacts of the military institution and escalated military spending greatly differ and include arguments that they either improve domestic economic performance or crowd out growth-inducing processes. Empirical findings on this matter are inconclusive, in part due to a failure to disentangle the various dimensions of military expenditures. We further suggest that modern sociology's relative inattention to such issues has contributed to these shortcomings. We explore a new dimension of military spending that clarifies this issue—military expenditures per soldier —which captures the capital intensiveness of a country’s military organization. Our cross-national panel regression and causal analyses of developed and less developed countries from 1990 to 2003 show that military expenditures per soldier inhibit the growth of per capita GDP, net of control variables, with the most pronounced effects in least developed countries. These expenditures inhibit national development in part by slowing the expansion of the labor force. Labor-intensive militaries may provide a pathway for upward mobility, but comparatively capital-intensive military organizations limit entry opportunities for unskilled and under- or unemployed people. Deep investments in military hardware also reduce the investment capital available for more economically productive opportunities. We also find that arms imports have a positive effect on economic growth, but only in less developed countries.

Thermal performance of an innovative roof component

Energy Technology Data Exchange (ETDEWEB)

Dimoudi, A. [Department of Environmental Engineering, Democritus University of Thrace, Vassilisis Sofias 12, 67 100 Xanthi (Greece); Lykoudis, S. [Institute for Environmental Research and Sustainable Development, National Observatory of Athens, I. Metaxa and B. Pavlou, 152 36 Penteli (Greece); Androutsopoulos, A. [Buildings Department, Division of Energy Efficiency, Centre for Renewable Energy Sources (CRES), 19th km Marathonos Aven., 190 09 Pikermi (Greece)

2006-11-15

In this paper, the thermal performance of a ventilated roof component is investigated during the winter period. The ventilated roof component consists of a conventional roof structure - reinforced concrete with a layer of thermal insulation - an air gap that allows the movement of the ambient air and an external layer made of a prefabricated concrete slab. The experimental results of the ventilated roof component during the winter period are presented and its thermal performance is analysed. The effect of key construction parameters like the height of the air gap and the use of a radiant barrier in the air gap is also investigated. Analysis of the results showed that the performance of a ventilated roof component is comparable to a conventional structure during winter. The ventilated component is shown to be in compliance with Greek regulatory requirements in terms of U-value. (author)

Thermal interface pastes nanostructured for high performance

Science.gov (United States)

Lin, Chuangang

Thermal interface materials in the form of pastes are needed to improve thermal contacts, such as that between a microprocessor and a heat sink of a computer. High-performance and low-cost thermal pastes have been developed in this dissertation by using polyol esters as the vehicle and various nanoscale solid components. The proportion of a solid component needs to be optimized, as an excessive amount degrades the performance, due to the increase in the bond line thickness. The optimum solid volume fraction tends to be lower when the mating surfaces are smoother, and higher when the thermal conductivity is higher. Both a low bond line thickness and a high thermal conductivity help the performance. When the surfaces are smooth, a low bond line thickness can be even more important than a high thermal conductivity, as shown by the outstanding performance of the nanoclay paste of low thermal conductivity in the smooth case (0.009 mum), with the bond line thickness less than 1 mum, as enabled by low storage modulus G', low loss modulus G" and high tan delta. However, for rough surfaces, the thermal conductivity is important. The rheology affects the bond line thickness, but it does not correlate well with the performance. This study found that the structure of carbon black is an important parameter that governs the effectiveness of a carbon black for use in a thermal paste. By using a carbon black with a lower structure (i.e., a lower DBP value), a thermal paste that is more effective than the previously reported carbon black paste was obtained. Graphite nanoplatelet (GNP) was found to be comparable in effectiveness to carbon black (CB) pastes for rough surfaces, but it is less effective for smooth surfaces. At the same filler volume fraction, GNP gives higher thermal conductivity than carbon black paste. At the same pressure, GNP gives higher bond line thickness than CB (Tokai or Cabot). The effectiveness of GNP is limited, due to the high bond line thickness. A

An Exploratory Study of the Relationship Between the Big-Five Personality Dimensions and Political Skills with Military Staff Members’ Perceived Performance

OpenAIRE

Alicia Ohlsson; Rhino Bandelitz Johansen; Gerry Larsson

2017-01-01

The purpose was to explore the relationship and mediation effects between the Big Five personality dimensions, and political skill with military staff members’ perceived performance. The sample included 185 Armed Forces International staff members from several military education facilities. The results indicated that the PSI and several personality dimensions were positively correlated with individuals’ perceived performance. In addition, the personality dimension Conscientiousness acted as a...

Best practices on institutional performance indicators system in R and D and I public organizations - the case of military organizations

Energy Technology Data Exchange (ETDEWEB)

Pereira, Maria Cecilia [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), SP (Brazil). Superintendencia da Qualidade]. E-mail: mcecilia37@hotmail.com; ctmsp-70b1@ctmsp.mar.mil.br; Zouain, Desiree Moraes [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: dmzouain@ipen.br

2007-07-01

This paper reflects the partial results of a Master degree research, performed in IPEN and CTMSP in Brazil. The focus of this research is to establish the best practices for an Institutional Performance Indicators System in Public Research, Development and Innovation (R and D and I) Organizations, particularly, the military ones. In public sector, especially military Institutes that are strongly committed to R and D and I, there have been changes in order to modernize the organization management. The focus, in our days, is on the Performance Indicator System, financial or not, strategic, tactic and operational, as a tool for the organizational control over the accomplishment of settled plans, the completion of the mission, everything according to a continuous improvement process. Among the many approaches underlying the development of a Performance Indicator System, since the 90s, the Balanced Scorecard - BSC stands out. It is based on the studies developed by Kaplan and Norton in 1986. By using the BSC approach, it is possible to construct a Performance Indicator System that makes available the information, financial or non-financial data, in logical format. This paper presents the results of the international and national experiences review of Institutional Performance Indicator Systems, applicable to the public organizations of R and D and I, preferably military organizations, and identify the best practices of these Systems. At the end of this paper, it is conducted a comparison among the experiences analyzed, in operation or planned, and are established some suggestions for an Institutional Performance Indicator System for a Military R and D and I Organization. (author)

Best practices on institutional performance indicators system in R and D and I public organizations - the case of military organizations

International Nuclear Information System (INIS)

Pereira, Maria Cecilia

2007-01-01

This paper reflects the partial results of a Master degree research, performed in IPEN and CTMSP in Brazil. The focus of this research is to establish the best practices for an Institutional Performance Indicators System in Public Research, Development and Innovation (R and D and I) Organizations, particularly, the military ones. In public sector, especially military Institutes that are strongly committed to R and D and I, there have been changes in order to modernize the organization management. The focus, in our days, is on the Performance Indicator System, financial or not, strategic, tactic and operational, as a tool for the organizational control over the accomplishment of settled plans, the completion of the mission, everything according to a continuous improvement process. Among the many approaches underlying the development of a Performance Indicator System, since the 90s, the Balanced Scorecard - BSC stands out. It is based on the studies developed by Kaplan and Norton in 1986. By using the BSC approach, it is possible to construct a Performance Indicator System that makes available the information, financial or non-financial data, in logical format. This paper presents the results of the international and national experiences review of Institutional Performance Indicator Systems, applicable to the public organizations of R and D and I, preferably military organizations, and identify the best practices of these Systems. At the end of this paper, it is conducted a comparison among the experiences analyzed, in operation or planned, and are established some suggestions for an Institutional Performance Indicator System for a Military R and D and I Organization. (author)

Transmutation Fuel Performance Code Thermal Model Verification

Energy Technology Data Exchange (ETDEWEB)

Gregory K. Miller; Pavel G. Medvedev

2007-09-01

FRAPCON fuel performance code is being modified to be able to model performance of the nuclear fuels of interest to the Global Nuclear Energy Partnership (GNEP). The present report documents the effort for verification of the FRAPCON thermal model. It was found that, with minor modifications, FRAPCON thermal model temperature calculation agrees with that of the commercial software ABAQUS (Version 6.4-4). This report outlines the methodology of the verification, code input, and calculation results.

A balanced strategy in managing steam generator thermal performance

International Nuclear Information System (INIS)

Hu, M. H.; Nelson, P. R.

2009-01-01

This paper presents a balanced strategy in managing thermal performance of steam generator designed to deliver rated megawatt thermal (MWt) and megawatt electric (MWe) power without loss with some amount of thermal margin. A steam generator (SG) is a boiling heat exchanger whose thermal performance may degrade because of steam pressure loss. In other words, steam pressure loss is an indicator of thermal performance degradation. Steam pressure loss is mainly a result of either 1) tube scale induced poor boiling or 2) tube plugging historically resulting from tubing corrosion, wear due to flow induced tube vibration or loose parts impact. Thermal performance degradation was historically due to tube plugging but more recently it is due to poor boiling caused by more bad than good constituents of feedwater impurities. The whole SG industry still concentrates solely on maintenance programs towards preventing causes for tube plugging and yet almost no programs on maintaining adequate boiling of fouled tubes. There can be an acceptable amount of tube scale that provides excellent boiling capacity without tubing corrosion, as operational experience has repeatedly demonstrated. Therefore, future maintenance has to come up balanced programs for allocating limited resources in both maintaining good boiling capacity and preventing tube plugging. This paper discusses also thermal performance degradation due to feedwater impurity induced blockage of tube support plate and thus subsequent water level oscillations, and how to mitigate them. This paper provides a predictive management of tube scale for maintaining adequate steam pressure and stable water level without loss in MWt/MWe or recovering from steam pressure loss or water level oscillations. This paper offers a balanced strategy in managing SG thermal performance to fulfill its mission. Such a strategy is even more important in view of the industry trend in pursuing extended power uprate as high as 20 percent

Thermal performance envelopes for MHTGRs - Reliability by design

International Nuclear Information System (INIS)

Etzel, K.T.; Howard, W.W.; Zgliczynski, J.

1992-01-01

Thermal performance envelopes are used to specify steady-state design requirements for the systems of the modular high-temperature gas-cooled reactor (MHTGR) to maximize plant performance reliability with optimized design. The thermal performance envelopes are constructed around the expected operating point to account for uncertainties in actual plant as-built parameters and plant operation. The components are then designed to perform successfully at all points within the envelope. As a result, plant reliability is maximized by accounting for component thermal performance variation in the design. The design is optimized by providing a means to determine required margins in a disciplined and visible fashion. This is accomplished by coordinating these requirements with the various system and component designers in the early stages of the design, applying the principles of total quality management. The design is challenged by the more complex requirements associated with a range of operating conditions, but in return, high probability of delivering reliable performance throughout the plant life is ensured

5 CFR 842.306 - Military service.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Military service. 842.306 Section 842.306... EMPLOYEES RETIREMENT SYSTEM-BASIC ANNUITY Credit for Service § 842.306 Military service. (a) Except as...' Retirement System Act of 1986, an employee's or Member's military service is creditable if it was performed...

The Reduction of Solid Waste Associated with Military Ration Packaging

National Research Council Canada - National Science Library

Ratto, Jo Ann; Lucciarini, Jeanne; Thellen, Christopher; Froio, Danielle; D'Souza, Nandika A

2006-01-01

... decrease the amount of solid waste generated by the military. These nanocomposites formulations were melt processed into films and characterized for barrier, mechanical, thermal, and biodegradation properties...

Effects of imperfect automation and individual differences on concurrent performance of military and robotics tasks in a simulated multitasking environment.

Science.gov (United States)

Chen, J Y C; Terrence, P I

2009-08-01

This study investigated the performance and workload of the combined position of gunner and robotics operator in a simulated military multitasking environment. Specifically, the study investigated how aided target recognition (AiTR) capabilities for the gunnery task with imperfect reliability (false-alarm-prone vs. miss-prone) might affect the concurrent robotics and communication tasks. Additionally, the study examined whether performance was affected by individual differences in spatial ability and attentional control. Results showed that when the robotics task was simply monitoring the video, participants had the best performance in their gunnery and communication tasks and the lowest perceived workload, compared with the other robotics tasking conditions. There was a strong interaction between the type of AiTR unreliability and participants' perceived attentional control. Overall, for participants with higher perceived attentional control, false-alarm-prone alerts were more detrimental; for low attentional control participants, conversely, miss-prone automation was more harmful. Low spatial ability participants preferred visual cueing and high spatial ability participants favoured tactile cueing. Potential applications of the findings include personnel selection for robotics operation, robotics user interface designs and training development. The present results will provide further understanding of the interplays among automation reliability, multitasking performance and individual differences in military tasking environments. These results will also facilitate the implementation of robots in military settings and will provide useful data to military system designs.

Nutritional armor for the warfighter: can omega-3 fatty acids enhance stress resilience, wellness, and military performance?

Science.gov (United States)

Deuster, Patricia

2014-11-01

This panel discussion, moderated by Dr. Deuster, illustrates the thinking of selected military leaders on the approach that must be taken to ensure the relationship between nutrition and performance. Insights and challenges these leaders face are provided, with consideration of the complex issues relating to sufficient scientific evidence, timing for Department of Defense policy, and the unique needs of service members. The discussion resulted in several recommendations. First, more nutritionists in uniform should be placed in/on the battlefield on every base and camp in Afghanistan and Iraq. Second, nutritionists/dietitians need to be working in the preventive arena, using the health promotion model and marketing to help shift behavior. Third, contract dietitians should be hired to work primarily in tertiary care. Dietitians must forward-deploy to implement preventive medicine and human performance optimization as it relates to nutrition and dietary supplementation. Unfortunately, almost all military dietitians are constrained within the medical model and we think of them just as "hospital providers." Finally, line units need to decide that dietitians are a requisite part of their force structure. Putting many dieticians in line units will allow our active duty members to believe diet and nutrition are important for performance. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

The Performance and Retention of Female Navy Officers with a Military Spouse

Science.gov (United States)

2017-03-01

the Army, family income , family size, career commitment, and job satisfaction .” As commitment is part of an officer’s performance, this thesis...between dual-military marriage and a Navy officer’s productivity. Although previous studies of marital status and job productivity may include dual- income ...career couples and single- and dual- income families within the U.S. Coast Guard. As the number of dual-career couples in the U.S. has continued to

Privatized Military Operations

Science.gov (United States)

2006-01-01

environment such as that in Abu Grahib prison , where military personnel tasked with similar duties to that of contractors have been held legally accountable... Grahib Prison . The Washington Post. Office of Management and Budget Circular A-76. (August 4, 1988. Revised 1999). Performance of Commercial...downsizes the military after the Global War on Terror as it did after the Cold War. Private contractors depend largely upon former service members to

Performance analysis of a lunar based solar thermal power system with regolith thermal storage

International Nuclear Information System (INIS)

Lu, Xiaochen; Ma, Rong; Wang, Chao; Yao, Wei

2016-01-01

The manned deep-space exploration is a hot topic of the current space activities. The continuous supply of thermal and electrical energy for the scientific equipment and human beings is a crucial issue for the lunar outposts. Since the night lasts for periods of about 350 h at most locations on the lunar surface, massive energy storage is required for continuous energy supply during the lengthy lunar night and the in-situ resource utilization is demanded. A lunar based solar thermal power system with regolith thermal storage is presented in this paper. The performance analysis is carried out by the finite-time thermodynamics to take into account major irreversible losses. The influences of some key design parameters are analyzed for system optimization. The analytical results shows that the lunar based solar thermal power system with regolith thermal storage can meet the requirement of the continuous energy supply for lunar outposts. - Highlights: • A lunar based solar thermal power system with regolith thermal storage is presented. • The performance analysis is carried out by the finite-time thermodynamics. • The influences of some key design parameters are analyzed.

An Exploratory Study of the Relationship Between the Big-Five Personality Dimensions and Political Skills with Military Staff Members’ Perceived Performance

Directory of Open Access Journals (Sweden)

Alicia Ohlsson

2017-10-01

Full Text Available The purpose was to explore the relationship and mediation effects between the Big Five personality dimensions, and political skill with military staff members’ perceived performance. The sample included 185 Armed Forces International staff members from several military education facilities. The results indicated that the PSI and several personality dimensions were positively correlated with individuals’ perceived performance. In addition, the personality dimension Conscientiousness acted as a statistically significant mediator between an individual’s use of political skills and their perceived performance. Practical considerations and future research directions are suggested.

Thermal performances of an insulating structure for a reactor vessel

International Nuclear Information System (INIS)

Aranovitch, E.; Crutzen, S.; Le Det, M.; Denis, R.

1974-12-01

This report describes the thermal and technological tests performed on a multilayer thermal insulation system for high temperature gas reactors. It includes the description of test facilities, global tests, interpretation of data, and technological tests. Results obtained make it possible to predetermine with a satisfactory precision thermal performances under various nominal conditions

Parametric study of closed wet cooling tower thermal performance

Science.gov (United States)

Qasim, S. M.; Hayder, M. J.

2017-08-01

The present study involves experimental and theoretical analysis to evaluate the thermal performance of modified Closed Wet Cooling Tower (CWCT). The experimental study includes: design, manufacture and testing prototype of a modified counter flow forced draft CWCT. The modification based on addition packing to the conventional CWCT. A series of experiments was carried out at different operational parameters. In view of energy analysis, the thermal performance parameters of the tower are: cooling range, tower approach, cooling capacity, thermal efficiency, heat and mass transfer coefficients. The theoretical study included develops Artificial Neural Network (ANN) models to predicting various thermal performance parameters of the tower. Utilizing experimental data for training and testing, the models simulated by multi-layer back propagation algorithm for varying all operational parameters stated in experimental test.

Ecological Aspects of the Performed Thermal Reclamation

Directory of Open Access Journals (Sweden)

Łucarz M.

2015-04-01

Full Text Available The thermal analysis results of the selected group of binders and the thermal reclamation of one spent moulding sand with organic binder, are presented in the paper. The reclaiming process of the quartz matrix was performed on the basis of the own method of selecting the reclamation temperature. Taking into account thermogravimetric (TG analysis results of the binder, the temperature range - required for performing the efficient reclamation of spent moulding sand containing this binder - was indicated. In order to confirm the assumptions, the thermal reclamation operations were carried out at a temperature similar to the determined on the TG basis and - for comparisons - at lower and higher temperatures. During the reclamation operation the reclaim samples were taken for the loss on ignition testing, aimed at the determination of the process efficiency. Temperature in the reclaimer chamber and gas consumptions were also recorded. On the bases of the thermal analyses, loss on ignition, gas consumption and temperatures of the reclaimed moulding sand bed the recommendations for the realisation of the thermal reclamation were given. These recommendations will allow a better, than currently available, process control in an aspect of decreasing the pyrolysis effect and limiting the emission of substances harmful for the environment.

Military Personnel: Performance Measures Needed to Determine How Well DOD’s Credentialing Program Helps Servicemembers

Science.gov (United States)

2016-10-01

MILITARY PERSONNEL Performance Measures Needed to Determine How Well DOD’s Credentialing Program Helps Servicemembers...Measures Needed to Determine How Well DOD’s Credentialing Program Helps Servicemembers What GAO Found The Department of Defense (DOD) has taken steps to...establish the statutorily required credentialing program, but it has not developed performance measures to gauge the program’s effectiveness

Thermal performance of Danish solar combi systems in practice and in theory

DEFF Research Database (Denmark)

Andersen, Elsa; Shah, Louise Jivan; Furbo, Simon

2004-01-01

An overview of measured thermal performances of Danish solar combi systems in practice is given. The thermal performance varies greatly from system to system. Measured and calculated thermal performances of different solar combi systems are compared and the main reasons for the different thermal ...... as theoretically expected....

Performance analysis of photovoltaic thermal (PVT) water collectors

International Nuclear Information System (INIS)

Fudholi, Ahmad; Sopian, Kamaruzzaman; Yazdi, Mohammad H.; Ruslan, Mohd Hafidz; Ibrahim, Adnan; Kazem, Hussein A.

2014-01-01

Highlights: • Performances analysis of PVT collector based on energy efficiencies. • New absorber designs of PVT collectors were presented. • Comparison present study with other absorber collector designs was presented. • High efficiencies were obtained for spiral flow absorber. - Abstract: The electrical and thermal performances of photovoltaic thermal (PVT) water collectors were determined under 500–800 W/m 2 solar radiation levels. At each solar radiation level, mass flow rates ranging from 0.011 kg/s to 0.041 kg/s were introduced. The PVT collectors were tested with respect to PV efficiency, thermal efficiency, and a combination of both (PVT efficiency). The results show that the spiral flow absorber exhibited the highest performance at a solar radiation level of 800 W/m 2 and mass flow rate of 0.041 kg/s. This absorber produced a PVT efficiency of 68.4%, a PV efficiency of 13.8%, and a thermal efficiency of 54.6%. It also produced a primary-energy saving efficiency ranging from 79% to 91% at a mass flow rate of 0.011–0.041 kg/s

Effect of thermal acclimation on thermal preference, resistance and locomotor performance of hatchling soft-shelled turtle

Directory of Open Access Journals (Sweden)

Mei-Xian WU,Ling-Jun HU, Wei DANG, Hong-Liang LU, Wei-Guo DU

2013-12-01

Full Text Available The significant influence of thermal acclimation on physiological and behavioral performance has been documented in many ectothermic animals, but such studies are still limited in turtle species. We acclimated hatchling soft-shelled turtles Pelodiscus sinensis under three thermal conditions (10, 20 and 30 °C for 4 weeks, and then measured selected body temperature (Tsel, critical thermal minimum (CTMin and maximum (CTMax, and locomotor performance at different body temperatures. Thermal acclimation significantly affected thermal preference and resistance of P. sinensis hatchlings. Hatchling turtles acclimated to 10 °C selected relatively lower body temperatures and were less resistant to high temperatures than those acclimated to 20 °C and 30 °C. The turtles’ resistance to low temperatures increased with a decreasing acclimation temperature. The thermal resistance range (i.e. the difference between CTMax and CTMin, TRR was widest in turtles acclimated to 20 °C, and narrowest in those acclimated to 10 °C. The locomotor performance of turtles was affected by both body temperature and acclimation temperature. Hatchling turtles acclimated to relatively higher temperatures swam faster than did those acclimated to lower temperatures. Accordingly, hatchling turtles acclimated to a particular temperature may not enhance the performance at that temperature. Instead, hatchlings acclimated to relatively warm temperatures have a better performance, supporting the “hotter is better” hypothesis [Current Zoology 59 (6 : 718–724, 2013 ].

Thermal performance enhancement in nanofluids containing diamond nanoparticles

International Nuclear Information System (INIS)

Xie Huaqing; Yu Wei; Li Yang

2009-01-01

Nanofluids, nanoparticle suspensions prepared by dispersing nanoscale particles in a base fluid, have been gaining interest lately due to their potential to greatly outperform traditional thermal transport liquids. Diamond has the highest thermal transport capacity in nature and diamond particles are often used as filler in mixtures for upgrading the performance of a matrix. It is reasonable to expect that the addition of diamond nanoparticles (DNPs) would lead to thermal performance enhancement in a base fluid. In this study, homogeneous and stable nanofluids composed of DNPs as the inclusions and a mixture of ethylene glycol (EG) and water as base fluid have been prepared. Acid mixtures of perchloric acid, nitric acid and hydrochloric acid were employed to purify and tailor the DNPs to eliminate impurities and to enhance their dispersibilty. Ultrasound and the alkalinity of solution are beneficial to the deaggregation of the soft DNP aggregations. The thermal conductivity enhancement of the DNP nanofluids increases with DNP loading and the thermal conductivity enhancement is more than 18.0% for a nanofluid at a DNP volume fraction of 0.02. Viscosity measurements show that the DNP nanofluids demonstrate Newtonian behaviour, and the viscosity significantly decreases with temperature. With increasing volume fraction of DNPs, the convective heat transfer coefficient increases first, and then decreases with a further increase in the volume fraction of DNPs. The nanofluid with a volume fraction of 0.005 has optimal overall thermal performance.

THERMAL PERFORMANCE OF FLAT PLATE SOLAR COLLECTOR

Directory of Open Access Journals (Sweden)

TABET I.

2017-06-01

Full Text Available In this paper, a theoretical and experimental studyof flat platesolar water collector with reflectors.A mathematical model based on energy balance equations saw the thermal behavior of the collector is investigated. The experimental test was made at the unit research applies in renewable energy (URAER located in southern Algeria.An increase of 23% for solar radiation incident on the collector surface with the addition of the planers reflectors in the day of May, this increase causes an improvement of the performance of the collector,the fluid temperature increases with an average of 5%. Thetests conducted on the flat plate solar water collector in open circuit enabled the determination of thermal performance of the collector by estimating the daily output The thermal efficiency of the collector ranges from 1% -63% during the day, a mean value of 36%obtained.

The use of creatine supplements in the military.

Science.gov (United States)

Havenetidis, Konstantinos

2016-08-01

Creatine is considered an effective nutritional ergogenic aid to enhance exercise performance. In spite of the publication of several reviews in the last decade on the topic of exercise performance/sports and creatine there is a need for an update related to the military given the lack of information in this area. The aim of this study was to critically assess original research addressing the use of creatine supplements in the military. A search of the electronic databases PubMed and SPORTDiscus, for the following key words: military personnel, trainees, recruit, soldier, physical fitness, physical conditioning, creatine supplementation, creatine ingestion, nutritional supplements to identify surveys and randomised clinical trials from journal articles and technical reports investigating the effect of creatine supplementation on military populations. Thirty-three out of 90 articles examined the use of creatine as a dietary supplement in military personnel. Twenty-one studies were finally selected on the basis of stated inclusion criteria for military surveys and randomised clinical trials. Most of the surveys (15/17) in the military indicate a high popularity of creatine (average 27%) among supplement users. In contrast, in most of the exercise protocols used (6/9) during randomised clinical trials creatine has produced a non-significant performance-enhancing effect. Creatine is one of the most widely used supplemental compounds in the military. It is not considered a doping infraction or related to any adverse health effects but its long-term usage needs further investigation. Experimental research suggests that creatine supplementation does not enhance physical performance in the military. However, limitations in creatine dosage, military fitness testing and sample group selection might have underestimated the ergogenic properties of creatine. Recent studies also indicate positive effects on various aspects of total force fitness such as cognitive

Experiment Investigation on Electrical and Thermal Performances of a Semitransparent Photovoltaic/Thermal System with Water Cooling

Directory of Open Access Journals (Sweden)

Guiqiang Li

2014-01-01

Full Text Available Different from the semitransparent building integrated photovoltaic/thermal (BIPV/T system with air cooling, the semitransparent BIPV/T system with water cooling is rare, especially based on the silicon solar cells. In this paper, a semitransparent photovoltaic/thermal system (SPV/T with water cooling was set up, which not only would provide the electrical power and hot water, but also could attain the natural illumination for the building. The PV efficiency, thermal efficiency, and exergy analysis were all adopted to illustrate the performance of SPV/T system. The results showed that the PV efficiency and the thermal efficiency were about 11.5% and 39.5%, respectively, on the typical sunny day. Furthermore, the PV and thermal efficiencies fit curves were made to demonstrate the SPV/T performance more comprehensively. The performance analysis indicated that the SPV/T system has a good application prospect for building.

Correlation between maximum isometric strength variables and specific performance of Brazilian military judokas

Directory of Open Access Journals (Sweden)

Michel Moraes Gonçalves

2017-06-01

Full Text Available It was our objective to correlate specific performance in the Special Judo Fitness Test (SJFT and the maximum isometric handgrip (HGSMax, scapular traction (STSMax and lumbar traction (LTSMax strength tests in military judo athletes. Twenty-two military athletes from the judo team of the Brazilian Navy Almirante Alexandrino Instruction Centre, with average age of 26.14 ± 3.31 years old, and average body mass of 83.23 ± 14.14 kg participated in the study. Electronic dynamometry tests for HGSMax, STSMax and LTSMax were conducted. Then, after approximately 1 hour-interval, the SJFT protocol was applied. All variables were adjusted to the body mass of the athletes. Pearson correlation coefficient for statistical analysis was used. The results showed moderate negative correlation between the SJFT index and STSMax (r= -0.550, p= 0.008, strong negative correlations between the SJFT index and HGSMax (r= -0.706, p< 0.001, SJFT index and LTSMax (r= -0.721; p= 0.001, besides the correlation between the sum of the three maximum isometric strength tests and the SJFT index (r= -0.786, p< 0.001. This study concludes that negative correlations occur between the SJFT index and maximum isometric handgrip, shoulder and lumbar traction strength and the sum of the three maximum isometric strength tests in military judokas.

High Performance Flat Plate Solar Thermal Collector Evaluation

Energy Technology Data Exchange (ETDEWEB)

Rockenbaugh, Caleb [National Renewable Energy Lab. (NREL), Golden, CO (United States); Dean, Jesse [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lovullo, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lisell, Lars [National Renewable Energy Lab. (NREL), Golden, CO (United States); Barker, Greg [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hanckock, Ed [National Renewable Energy Lab. (NREL), Golden, CO (United States); Norton, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-09-01

This report was prepared for the General Services Administration by the National Renewable Energy Laboratory. The Honeycomb Solar Thermal Collector (HSTC) is a flat plate solar thermal collector that shows promising high efficiencies over a wide range of climate zones. The technical objectives of this study are to: 1) verify collector performance, 2) compare that performance to other market-available collectors, 3) verify overheat protection, and 4) analyze the economic performance of the HSTC both at the demonstration sites and across a matrix of climate zones and utility markets.

Air-Filled Nanopore Based High-Performance Thermal Insulation Materials

OpenAIRE

Gangåssæter, Haakon Fossen; Jelle, Bjørn Petter; Alex Mofid, Sohrab; Gao, Tao

2017-01-01

State-of-the-art thermal insulation solutions like vacuum insulation panels (VIP) and aerogels have low thermal conductivity, but their drawbacks may make them unable to be the thermal insulation solutions that will revolutionize the building industry regarding energy-efficient building envelopes. Nevertheless, learning from these materials may be crucial to make new and novel high-performance thermal insulation products. This study presents a review on the state-of-the-art air-filled thermal...

Performance reliability prediction for thermal aging based on kalman filtering

International Nuclear Information System (INIS)

Ren Shuhong; Wen Zhenhua; Xue Fei; Zhao Wensheng

2015-01-01

The performance reliability of the nuclear power plant main pipeline that failed due to thermal aging was studied by the performance degradation theory. Firstly, through the data obtained from the accelerated thermal aging experiments, the degradation process of the impact strength and fracture toughness of austenitic stainless steel material of the main pipeline was analyzed. The time-varying performance degradation model based on the state space method was built, and the performance trends were predicted by using Kalman filtering. Then, the multi-parameter and real-time performance reliability prediction model for the main pipeline thermal aging was developed by considering the correlation between the impact properties and fracture toughness, and by using the stochastic process theory. Thus, the thermal aging performance reliability and reliability life of the main pipeline with multi-parameter were obtained, which provides the scientific basis for the optimization management of the aging maintenance decision making for nuclear power plant main pipelines. (authors)

Young Australians’ Attitudes to the Military and Military Service

Directory of Open Access Journals (Sweden)

Ben Wadham

2014-08-01

Full Text Available What are young Australians’ understandings of, and attitudes to, the military and military service? This article describes a pilot study of 320 young Australian university students’ attitudes to the military and military service during a time when Australia was engaged in the Afghanistan war. The main purpose of this study was to develop a survey instrument for further work in researching civil–military relations in Australia. Civil–military relations describe the complex set of relationships between the civil and military spheres. The role of the military, the relationship between the state and the military, the division of labor between civilian and military entities, foreign policy, and knowledge of military service are some of the fields that constitute a study of civil–military relations. This article reports on beliefs about, and attitudes to the specificities of military service and responses to the broader field of civil–military relations.

A Facile Approach to Evaluate Thermal Insulation Performance of Paper Cups

Directory of Open Access Journals (Sweden)

Yudi Kuang

2015-01-01

Full Text Available Paper cups are ubiquitous in daily life for serving water, soup, coffee, tea, and milk due to their convenience, biodegradability, recyclability, and sustainability. The thermal insulation performance of paper cups is of significance because they are used to supply hot food or drinks. Using an effective thermal conductivity to accurately evaluate the thermal insulation performance of paper cups is complex due to the inclusion of complicated components and a multilayer structure. Moreover, an effective thermal conductivity is unsuitable for evaluating thermal insulation performance of paper cups in the case of fluctuating temperature. In this work, we propose a facile approach to precisely analyze the thermal insulation performance of paper cups in a particular range of temperature by using an evaluation model based on the MISO (Multiple-Input Single-Output technical theory, which includes a characterization parameter (temperature factor and a measurement apparatus. A series of experiments was conducted according to this evaluation model, and the results show that this evaluation model enables accurate characterization of the thermal insulation performance of paper cups and provides an efficient theoretical basis for selecting paper materials for paper cups.

The Assessment of Military Multitasking Performance: Validation of a Dual-Task and Multitask Protocol

Science.gov (United States)

2014-08-01

multitasks using healthy control and SM with diagnosed mTBI. Approach: Inter-rater reliability and assessment of training requirements for expert...developers piloted the revised multitask assessment in a healthy population to assess IRR. Given the an- ticipated variability in task performance between...1 AD_________________ Award Number: Contract W81XWH-12-2-0070 TITLE: Annual Report: The Assessment of Military Multitasking

PTSD is negatively associated with physical performance and physical function in older overweight military veterans

OpenAIRE

Hall, Katherine S.; Beckham, Jean C.; Bosworth, Hayden B.; Sloane, Richard; Pieper, Carl F.; Morey, Miriam C.

2014-01-01

This study examines the effect of posttraumatic stress disorder (PTSD) on function and physical performance in older overweight military Veterans with comorbid conditions. This is a secondary data analysis of older Veterans (mean age = 62.9 yr) participating in a physical activity counseling trial. Study participants with PTSD (n = 67) and without PTSD (n = 235) were identified. Self-reported physical function (36-item Short Form Health Survey) and directly measured physical performance (mobi...

Study of skin model and geometry effects on thermal performance of thermal protective fabrics

Science.gov (United States)

Zhu, Fanglong; Ma, Suqin; Zhang, Weiyuan

2008-05-01

Thermal protective clothing has steadily improved over the years as new materials and improved designs have reached the market. A significant method that has brought these improvements to the fire service is the NFPA 1971 standard on structural fire fighters’ protective clothing. However, this testing often neglects the effects of cylindrical geometry on heat transmission in flame resistant fabrics. This paper deals with methods to develop cylindrical geometry testing apparatus incorporating novel skin bioheat transfer model to test flame resistant fabrics used in firefighting. Results show that fabrics which shrink during the test can have reduced thermal protective performance compared with the qualities measured with a planar geometry tester. Results of temperature differences between skin simulant sensors of planar and cylindrical tester are also compared. This test method provides a new technique to accurately and precisely characterize the thermal performance of thermal protective fabrics.

Emission and thermal performance upgrade through advanced control backfit

Energy Technology Data Exchange (ETDEWEB)

Banerjee, A.K. [Stone & Webster Engineering Corporation, Boston, MA (United States)

1994-12-31

Reducing emission and improving thermal performance of currently operating power plants is a high priority. A majority of these power plants are over 20 years old with old control systems. Upgrading the existing control systems with the latest technology has many benefits, the most cost beneficial are the reduction of emission and improving thermal performance. The payback period is usually less than two years. Virginia Power is installing Stone & Webster`s NO{sub x} Emissions Advisor and Advanced Steam Temperature Control systems on Possum Point Units 3 and 4 to achieve near term NO{sub x} reductions while maintaining high thermal performance. Testing has demonstrated NO{sub x} reductions of greater than 20 percent through the application of NO{sub x} Emissions Advisor on these units. The Advanced Steam Temperature Control system which has been operational at Virginia Power`s Mt. Storm Unit 1 has demonstrated a signification improvement in unit thermal performance and controllability. These control systems are being combined at Units 3 and 4 to reduce NO{sub x} emissions and achieve improved unit thermal performance and control response with the existing combustion hardware. Installation has been initiated and is expected to be completed by the spring of 1995. Possum Point Power Station Units 3 and 4 are pulverized coal, tangentially fired boilers producing 107 and 232 MW and have a distributed control system and a PC based performance monitoring system. The installation of the advanced control and automation system will utilize existing control equipment requiring the addition of several PCs and PLC.

Thermal performance of the ATST secondary mirror

Science.gov (United States)

Cho, Myung K.; DeVries, Joe; Hansen, Eric

2007-12-01

The Advanced Technology Solar Telescope (ATST) has a 4.24m off-axis primary mirror designed to deliver diffractionlimited images of the sun. Its baseline secondary mirror (M2) design uses a 0.65m diameter Silicon Carbide mirror mounted kinematically by a bi-pod flexure mechanism at three equally spaced locations. Unlike other common telescopes, the ATST M2 is to be exposed to a significant solar heat loading. A thermal management system (TMS) will be developed to accommodate the solar loading and minimize "mirror seeing effect" by controlling the temperature difference between the M2 optical surface and the ambient air at the site. Thermo-elastic analyses for steady state thermal behaviors of the ATST secondary mirror was performed using finite element analysis by I-DEAS TM and PCRINGE TM for the optical analysis. We examined extensive heat transfer simulation cases and their results were discussed. The goal of this study is to establish thermal models by I-DEAS for an adequate thermal environment. These thermal models will be useful for estimating segment thermal responses. Current study assumes a few sample time dependent thermal loadings to synthesize the operational environment.

Human Performance Modeling in Military Simulation: Current State of the Art and the Way Ahead (2002 TTCP HUM Group Meeting)

National Research Council Canada - National Science Library

2004-01-01

.... This report examines the requirements for human performance modeling within the military, assesses the state of the practice in current operational models, documents ongoing human performance research and development (R and D...

Thermal performances of ETFE cushion roof integrated amorphous silicon photovoltaic

International Nuclear Information System (INIS)

Hu, Jianhui; Chen, Wujun; Qiu, Zhenyu; Zhao, Bing; Zhou, Jinyu; Qu, Yegao

2015-01-01

Highlights: • Thermal performances of a three layer ETFE cushion integrated a-Si PV is evaluated. • Temperature of a-Si PV obviously affects temperature field and temperature boundary. • The maximum temperature difference of 3.4 K between measured and numerical results. • Main transport mechanisms in upper and lower chambers are convection and conduction. • Heat transfer coefficients of this roof are less than those of other ETFE cushion roofs. - Abstract: Thermal performances of the ETFE cushion roof integrated amorphous silicon photovoltaic (a-Si PV) are essential to estimate building performances, such as temperature distribution and heat transfer coefficient. To investigate these thermal performances, an experimental mock-up composed of a-Si PV and a three-layer ETFE cushion roof was built and the experiment was carried out under summer sunny condition. Meanwhile, numerical model with real boundary conditions was performed in this paper. The experimental results show that the temperature sequence of the three layers was the middle, top and bottom layer and that the PV temperature caused by solar irradiance was 353.8 K. This gives evidence that the PV has a significant effect on the temperature distribution. The experimental temperature was in good agreement with the corresponding location of the numerical temperature since the maximum temperature difference was only 3.4 K. Therefore, the numerical results were justified and then used to analyze the airflow characteristics and calculate the thermal performances. For the airflow characteristics, it is found that the temperature distribution was not uniform and the main transport mechanisms in the upper and lower chambers formed by the three layers were the convection and conduction, respectively. For the thermal performances, the surface convective heat transfer coefficients were obtained, which have validated that thermal performances of the three-layer ETFE cushion integrated a-Si PV are better than

Analysis of Unmanned Systems in Military Logistics

Science.gov (United States)

2016-12-01

performance measures: customer satisfaction , flexibility, visibility, and trust. If we apply this explanation of Li and Schulze (2011) to the military...unmanned systems, initially, we aimed to define current and proposed unmanned applications in civilian-sector logistics and current military...aimed to define current and proposed unmanned applications in civilian-sector logistics and current military logistics challenges. Then, justifying

Thermal performances of molten salt steam generator

International Nuclear Information System (INIS)

Yuan, Yibo; He, Canming; Lu, Jianfeng; Ding, Jing

2016-01-01

Highlights: • Thermal performances of molten salt steam generator were experimentally studied. • Overall heat transfer coefficient reached maximum with optimal molten salt flow rate. • Energy efficiency first rose and then decreased with salt flow rate and temperature. • Optimal molten salt flow rate and temperature existed for good thermal performance. • High inlet water temperature benefited steam generating rate and energy efficiency. - Abstract: Molten salt steam generator is the key technology for thermal energy conversion from high temperature molten salt to steam, and it is used in solar thermal power station and molten salt reactor. A shell and tube type molten salt steam generator was set up, and its thermal performance and heat transfer mechanism were studied. As a coupling heat transfer process, molten salt steam generation is mainly affected by molten salt convective heat transfer and boiling heat transfer, while its energy efficiency is also affected by the heat loss. As molten salt temperature increased, the energy efficiency first rose with the increase of heat flow absorbed by water/steam, and then slightly decreased for large heat loss as the absorbed heat flow still rising. At very high molten salt temperature, the absorbed heat flow decreased as boiling heat transfer coefficient dropping, and then the energy efficiency quickly dropped. As the inlet water temperature increased, the boiling region in the steam generator remarkably expanded, and then the steam generation rate and energy efficiency both rose with the overall heat transfer coefficient increasing. As the molten salt flow rate increased, the wall temperature rose and the boiling heat transfer coefficient first increased and then decreased according to the boiling curve, so the overall heat transfer coefficient first increased and then decreased, and then the steam generation rate and energy efficiency of steam generator both had maxima.

The Fuel Performance Analysis of LWR Fuel containing High Thermal Conductivity Reinforcements

International Nuclear Information System (INIS)

Kim, Seung Su; Ryu, Ho Jin

2015-01-01

The thermal conductivity of fuel affects many performance parameters including the fuel centerline temperature, fission gas release and internal pressure. In addition, enhanced safety margin of fuel might be expected when the thermal conductivity of fuel is improved by the addition of high thermal conductivity reinforcements. Therefore, the effects of thermal conductivity enhancement on the fuel performance of reinforced UO2 fuel with high thermal conductivity compounds should be analyzed. In this study, we analyzed the fuel performance of modified UO2 fuel with high thermal conductivity reinforcements by using the FRAPCON-3.5 code. The fissile density and mechanical properties of the modified fuel are considered the same with the standard UO2 fuel. The fuel performance of modified UO2 with high thermal conductivity reinforcements were analyzed by using the FRAPCON-3.5 code. The thermal conductivity enhancement factors of the modified fuels were obtained from the Maxwell model considering the volume fraction of reinforcements

Thermal performance analysis of a solar heating plant

DEFF Research Database (Denmark)

Fan, Jianhua; Huang, Junpeng; Andersen, Ola Lie

was developed to calculate thermal performances of the plant. In the Trnsys model, three solar collector fields with a total solar collector area of 33,300 m2, a seasonal water pit heat storage of 75,000 m3, a simplified CO2 HP, a simplified ORC unit and a simplified wood chip boiler were included. The energy......Detailed measurements were carried out on a large scale solar heating plant located in southern Denmark in order to evaluate thermal performances of the plant. Based on the measurements, energy flows of the plant were evaluated. A modified Trnsys model of the Marstal solar heating plant...... consumption of the district heating net was modeled by volume flow rate and given forward and return temperatures of the district heating net. Weather data from a weather station at the site of the plant were used in the calculations. The Trnsys calculated yearly thermal performance of the solar heating plant...

Dynamic thermal performance of alveolar brick construction system

International Nuclear Information System (INIS)

Gracia, A. de; Castell, A.; Medrano, M.; Cabeza, L.F.

2011-01-01

Highlights: → Even though U-value does not measure thermal inertia, it is the commonly used parameter. → The thermal performance analysis of buildings must include the evaluation of transient parameters. → Transient parameters of alveolar brick constructive system show good agreement with its low energy consumption. -- Abstract: Alveolar bricks are being introduced in building sector due to the simplicity of their construction system and to the elimination of the insulation material. Nevertheless, it is not clear if this new system is energetically efficient and which is its thermal behaviour. This paper presents an experimental and theoretical study to evaluate the thermal behaviour of the alveolar brick construction system, compared with a traditional Mediterranean brick system with insulation. The experimental study consists of measuring the thermal performance of four real house-like cubicles. The thermal transmittance in steady-state, also known as U-value, is calculated theoretically and experimentally for each cubicle, presenting the insulated cubicles as the best construction system, with differences around 45% in comparison to the alveolar one. On the other hand, experimental results show significantly smaller differences on the energy consumption between the alveolar and insulated construction systems during summer period (around 13% higher for the alveolar cubicle). These values demonstrate the high thermal efficiency of the alveolar system. In addition, the lack of agreement between the measured energy consumption and the calculated U-values, guides the authors to analyze the thermal inertia of the different building components. Therefore, several transient parameters, extracted from the heat transfer matrix and from experimental data, are also evaluated. It can be concluded that the alveolar brick construction system presents higher thermal inertia than the insulated one, justifying the low measured energy consumption.

Study of the electrical and thermal performances of photovoltaic thermal collector-compound parabolic concentrated

Directory of Open Access Journals (Sweden)

Ahed Hameed Jaaz

2018-06-01

Full Text Available The importance of utilizing the solar energy as a very suitable source among multi-source approaches to replace the conventional energy is on the rise in the last four decades. The invention of the photovoltaic module (PV could be the corner stone in this process. However, the limited amount of energy obtained from PV was and still the main challenge of full utilization of the solar energy. In this paper, the use of the compound parabolic concentrator (CPC along with the thermal photovoltaic module (PVT where the cooling process of the CPC is conducted using a novel technique of water jet impingement has applied experimentally and physically tested. The test includes the effect of water jet impingement on the total power, electrical efficiency, thermal efficiency, and total efficiency on CPC-PVT system. The cooling process at the maximum irradiation by water jet impingement resulted in improving the electrical efficiency by 7%, total output power by 31% and the thermal efficiency by 81%. These results outperform the recent highest results recorded by the most recent work. Keywords: Photovoltaic thermal collectors, Electrical performance, Thermal performance, Compound parabolic concentrator, Jet impingement

Investigation of Thermal Performance for Atria: a Method Overview

Directory of Open Access Journals (Sweden)

Moosavi Leila

2016-01-01

Full Text Available The importance of low energy design in large buildings has encouraged researchers to implement different methods for predicting a building’s thermal performance. Atria, as energy efficient features, have been implemented to improve the indoor thermal environment in large modern buildings. Though widely implemented, the thorough study of atrium performance is restricted due to its large size, complex thermodynamic behavior and the inaccuracies and limitations of available prediction tools. This study reviews the most common research tools implemented in previous researches on atria thermal performance, to explore the advantages and limitation of different methods for future studies. The methods reviewed are analytical, experimental, computer modelling and a combination of any or all of these methods. The findings showed that CFD (computational fluid dynamic models are the most popular tools of recent due to their higher accuracy, capabilities and user-friendly modification. Although the experimental methods were reliable for predicting atria thermal and ventilation performance, they have mostly been used to provide data for validation of CFD models. Furthermore, coupling CFD with other experimental models could increase the reliability and accuracy of the models and provide a more comprehensive analysis.

Performance testing of thermal analysis codes for nuclear fuel casks

International Nuclear Information System (INIS)

Sanchez, L.C.

1987-01-01

In 1982 Sandia National Laboratories held the First Industry/Government Joint Thermal and Structural Codes Information Exchange and presented the initial stages of an investigation of thermal analysis computer codes for use in the design of nuclear fuel shipping casks. The objective of the investigation was to (1) document publicly available computer codes, (2) assess code capabilities as determined from their user's manuals, and (3) assess code performance on cask-like model problems. Computer codes are required to handle the thermal phenomena of conduction, convection and radiation. Several of the available thermal computer codes were tested on a set of model problems to assess performance on cask-like problems. Solutions obtained with the computer codes for steady-state thermal analysis were in good agreement and the solutions for transient thermal analysis differed slightly among the computer codes due to modeling differences

Numerical investigation of temperature distribution and thermal performance while charging-discharging thermal energy in aquifer

International Nuclear Information System (INIS)

Ganguly, Sayantan; Mohan Kumar, M.S.; Date, Abhijit; Akbarzadeh, Aliakbar

2017-01-01

Highlights: • A 3D coupled thermo-hydrogeological numerical model of an ATES system is presented. • Importance of a few parameters involved in the study is determined. • Thermal energy discharge by the ATES system for two seasons is estimated. • A strategy and a safe well spacing are proposed to avoid thermal interference. • The proposed model is applied to simulate a real life ATES field study. - Abstract: A three-dimensional (3D) coupled thermo-hydrogeological numerical model for a confined aquifer thermal energy storage (ATES) system underlain and overlain by rock media has been presented in this paper. The ATES system operates in cyclic mode. The model takes into account heat transport processes of advection, conduction and heat loss to confining rock media. The model also includes regional groundwater flow in the aquifer in the longitudinal and lateral directions, geothermal gradient and anisotropy in the aquifer. Results show that thermal injection into the aquifer results in the generation of a thermal-front which grows in size with time. The thermal interference caused by the premature thermal-breakthrough when the thermal-front reaches the production well results in the fall of system performance and hence should be avoided. This study models the transient temperature distribution in the aquifer for different flow and geological conditions which may be effectively used in designing an efficient ATES project by ensuring safety from thermal-breakthrough while catering to the energy demand. Parameter studies are also performed which reveals that permeability of the confining rocks; well spacing and injection temperature are important parameters which influence transient heat transport in the subsurface porous media. Based on the simulations here a safe well spacing is proposed. The thermal energy produced by the system in two seasons is estimated for four different cases and strategy to avoid the premature thermal-breakthrough in critical cases is

Quantification of thermal damage in skin tissue

Institute of Scientific and Technical Information of China (English)

徐峰; 文婷; 卢天健; Seffen; Keith

2008-01-01

Skin thermal damage or skin burns are the most commonly encountered type of trauma in civilian and military communities. Besides, advances in laser, microwave and similar technologies have led to recent developments of thermal treatments for disease and damage involving skin tissue, where the objective is to induce thermal damage precisely within targeted tissue structures but without affecting the surrounding, healthy tissue. Further, extended pain sensation induced by thermal damage has also brought great...

The thermal performance of earth buildings

Directory of Open Access Journals (Sweden)

Heathcote, K.

2011-09-01

Full Text Available This paper examines the theoretical basis for the thermal performance of earth walls and links it to some test results on buildings constructed by the author, and to their predicted performance using a sophisticated computer modelling program. The analysis shows that for all earth walls the steady state thermal resistance is low but that for walls greater than about 450 mm thick the cyclic thermal resistance is high and increases exponentially. Whilst the steady state resistance of all thickness walls is low and results in higher than normal average temperatures in summer and lower than normal in winter the ability of thick earth walls to even out the swings in temperature is thought to be responsible for the materials reputation. The paper notes that good passive design principles (such as providing internal thermal mass and large areas of glazing for winter performance will greatly improve the performance of earth buildings with thin walls, but it is the author’s opinion that external earth walls should be at least 450 mm thick to gain the full benefit of thermal mass.

Este artículo examina la base teórica del comportamiento térmico de las paredes de tierra y la relaciona con varios resultados de test realizados sobre edificios construidos por el autor, y con su comportamiento previsto utilizando un sofisticado programa de modelado por ordenador. El análisis muestra que la resistencia térmica constante es baja para todas las paredes de tierra, pero que para muros con un grosor mayor que 450 mm la resistencia térmica cíclica es alta y se incrementa exponencialmente. Mientras que la resistencia térmica constante de las paredes de cualquier grosor es baja y se traduce en temperaturas más altas que la media en verano y más bajas que la media en invierno, la capacidad de las paredes gruesas de tierra para amortiguar las variaciones de temperatura es la responsable de la reputación de los materiales. El artículo señala que los

Nutrition and Physical Performance in Military Environments

Science.gov (United States)

1987-12-01

as in military field trials. 2.0 Selective macronutrient utiliation and exercise Intensity Newsholme and Leech (5) calculated the duration of time...activities which demand short bursts of explosive power for only a few seconds. With regard to specific macronutrients , the availability of carbohydrates...187 g carbohydrate per day. Further support comes from a study by Saltin (17) on two teams of soccer players, one of which exercised hard to become

Thermal comfort, physiological responses and performance during exposure to a moderate temperature drift

DEFF Research Database (Denmark)

Schellen, Lisje; van Marken Lichtenbelt, Wouter; de Wit, Martin

2008-01-01

The objective of this research was to study the effects of a moderate temperature drift on human thermal comfort, physiological responses, productivity and performance. A dynamic thermophysiological model was used to examine the possibility of simulating human thermal responses and thermal comfort...... temperature corresponding with a neutral thermal sensation (control situation). During the experiments both physiological responses and thermal sensation were measured. Productivity and performance were assessed with a ‘Remote Performance Measurement’ (RPM) method. Physiological and thermal sensation data...

Thermal performance of the Atlas SCT forward modules

CERN Document Server

Clark, A; Nasteva, I; Snow, S W; Wallny, R; Wilmut, I

2003-01-01

We describe the thermal design of the Atlas SCT forward modules and their cooling blocks. We report on the performance of the $C_3 F_8$ evaporative cooling system and the blocks alone, then on the performance of an irradiated inner module mounted on two alternative prototype cooling blocks (baseline and PEEK split). Runs are presented at different cooling conditions, representative of those expected to be used in the final experiment. We have also measured thermal runaway, with the module mounted on the PEEK split block and cooled with liquid cooling.

Thermal performance curves under daily thermal fluctuation: A study in helmeted water toad tadpoles.

Science.gov (United States)

Bartheld, José L; Artacho, Paulina; Bacigalupe, Leonardo

2017-12-01

Most research in physiological ecology has focused on the effects of mean changes in temperature under the classic "hot vs cold" acclimation treatment; however, current evidence suggests that an increment in both the mean and variance of temperature could act synergistically to amplify the negative effects of global temperature increase and how it would affect fitness and performance-related traits in ectothermic organisms. We assessed the effects of acclimation to daily variance of temperature on thermal performance curves of swimming speed in helmeted water toad tadpoles (Calyptocephalella gayi). Acclimation treatments were 20°C ± 0.1 SD (constant) and 20°C ± 1.5 SD (fluctuating). We draw two key findings: first, tadpoles exposed to daily temperature fluctuation had reduced maximal performance (Z max ), and flattened thermal performance curves, thus supporting the "vertical shift or faster-slower" hypothesis, and suggesting that overall swimming performance would be lower through an examination of temperatures under more realistic and ecologically-relevant fluctuating regimens; second, there was significant interindividual variation in performance traits by means of significant repeatability estimates. Our present results suggest that the widespread use of constant acclimation temperatures in laboratory experiments to estimate thermal performance curves (TPCs) may lead to an overestimation of actual organismal performance. We encourage the use of temperature fluctuation acclimation treatments to better understand the variability of physiological traits, which predict ecological and evolutionary responses to global change. Copyright © 2017 Elsevier Ltd. All rights reserved.

Thermal Performance Analyses of Multiborehole Ground Heat Exchangers

Directory of Open Access Journals (Sweden)

Wanjing Luo

2017-01-01

Full Text Available Geothermal energy known as a clean, renewable energy resource is widely available and reliable. Ground heat exchangers (GHEs can assist the development of geothermal energy by reducing the capital cost and greenhouse gas emission. In this paper, a novel semianalytical method was developed to study the thermal performance of multiborehole ground heat exchangers (GHEs with arbitrary configurations. By assuming a uniform inlet fluid temperature (UIFT, instead of uniform heat flux (UHF, the effects of thermal interference and the thermal performance difference between different boreholes can be examined. Simulation results indicate that the monthly average outlet fluid temperatures of GHEs will increase gradually while the annual cooling load of the GHEs is greater than the annual heating load. Besides, two mechanisms, the thermal dissipation and the heat storage effect, will determine the heat transfer underground, which can be further divided into four stages. Moreover, some boreholes will be malfunctioned; that is, boreholes can absorb heat from ground when the GHEs are under the cooling mode. However, as indicated by further investigations, this malfunction can be avoided by increasing borehole spacing.

Thermal Model Predictions of Advanced Stirling Radioisotope Generator Performance

Science.gov (United States)

Wang, Xiao-Yen J.; Fabanich, William Anthony; Schmitz, Paul C.

2014-01-01

This paper presents recent thermal model results of the Advanced Stirling Radioisotope Generator (ASRG). The three-dimensional (3D) ASRG thermal power model was built using the Thermal Desktop(trademark) thermal analyzer. The model was correlated with ASRG engineering unit test data and ASRG flight unit predictions from Lockheed Martin's (LM's) I-deas(trademark) TMG thermal model. The auxiliary cooling system (ACS) of the ASRG is also included in the ASRG thermal model. The ACS is designed to remove waste heat from the ASRG so that it can be used to heat spacecraft components. The performance of the ACS is reported under nominal conditions and during a Venus flyby scenario. The results for the nominal case are validated with data from Lockheed Martin. Transient thermal analysis results of ASRG for a Venus flyby with a representative trajectory are also presented. In addition, model results of an ASRG mounted on a Cassini-like spacecraft with a sunshade are presented to show a way to mitigate the high temperatures of a Venus flyby. It was predicted that the sunshade can lower the temperature of the ASRG alternator by 20 C for the representative Venus flyby trajectory. The 3D model also was modified to predict generator performance after a single Advanced Stirling Convertor failure. The geometry of the Microtherm HT insulation block on the outboard side was modified to match deformation and shrinkage observed during testing of a prototypic ASRG test fixture by LM. Test conditions and test data were used to correlate the model by adjusting the thermal conductivity of the deformed insulation to match the post-heat-dump steady state temperatures. Results for these conditions showed that the performance of the still-functioning inboard ACS was unaffected.

Thermal Performance of the Storage Brick Containing Microencapsulated PCM

International Nuclear Information System (INIS)

Lee, Dong Gyu

1998-02-01

The utilization of microencapsulated phase change materials(PCMs) provides several advantages over conventional PCM application. The heat storage system, as well as heat recovery system, can be built to a smaller size than the normal systems for a given thermal cycling capacity. This microencapsulated PCM technique has not yet been commercialized, however. In this work sodium acetate trihydrate(CH 3 COONa · 3H 2 O) was selected for the PCM and was encapsulated. This microencapsulated PCM was mixed with cement mortar for utilization as a floor heating system. In this experiment performed here the main purpose was to investigate the thermal performance of a storage brick with microencapsulated PCM concentration. The thermal performance of this storage brick is dependent on PCM concentration, flow rate and cooling temperature of the heat transfer fluid, etc. The results showed that cycle time was shortened as the PCM content was increased and as the mass flow rate was increased. The same effect was obtained when the cooling temperature was decreased. For each thermal storage brick the overall heat transfer coefficient(U-value) was constant for a 0% brick, but was increased with time for the bricks containing microencapsulated PCM. For the same mass flow rate, as the cooling temperature decreased, the amount of heat withdrawn increased, and in particular a critical cooling temperature was found for each thermal storage brick. The average effectiveness of each thermal storage brick was found to be approximately 48%, 51% and 58% respectively

MILITARY COMPETITION BETWEEN FRIENDS? HEGEMONIC DEVELOPMENT AND MILITARY SPENDING AMONG EIGHT WESTERN DEMOCRACIES, 1920-1938

Directory of Open Access Journals (Sweden)

Jari Eloranta

2001-01-01

Full Text Available This article explores the complicated phenomenon of military spending among a sample of eight Western democracies in the interwar period by analyzing especially the possibility of economic and/or military competition between the Western Great Powers and the ensuing impacts on the smaller states included here. The hegemonic paradigm suggested by e.g. Paul Kennedy predicts that the economic leader in a system will increasingly invest on maintaining security; thus eventually bringing economic growth to a halt. The military spending patterns respective of economic growth at first seem to suggest that not only the totalitarian states, as is the traditional view, but also the UK and France stepped in to fill the void created by the lack of American leadership. However, the military expenditures of these nations were too low to warrant the conclusion that they had any impact on their respective economic performance. This result is also verified here by employing Granger non-causality tests between the military spending and economic growth variables. Moreover, regression analysis on the military spending variables for the UK and France points towards competition on the level. The smaller states, respectively, seemed to follow the UK and France fairly closely in their military spending decisions.

Comparative analyses on dynamic performances of photovoltaic–thermal solar collectors integrated with phase change materials

International Nuclear Information System (INIS)

Su, Di; Jia, Yuting; Alva, Guruprasad; Liu, Lingkun; Fang, Guiyin

2017-01-01

Highlights: • The dynamic model of photovoltaic–thermal collector with phase change material was developed. • The performances of photovoltaic–thermal collector are performed comparative analyses. • The performances of photovoltaic–thermal collector with phase change material were evaluated. • Upper phase change material mode can improve performances of photovoltaic–thermal collector. - Abstract: The operating conditions (especially temperature) of photovoltaic–thermal solar collectors have significant influence on dynamic performance of the hybrid photovoltaic–thermal solar collectors. Only a small percentage of incoming solar radiation can be converted into electricity, and the rest is converted into heat. This heat leads to a decrease in efficiency of the photovoltaic module. In order to improve the performance of the hybrid photovoltaic–thermal solar collector, we performed comparative analyses on a hybrid photovoltaic–thermal solar collector integrated with phase change material. Electrical and thermal parameters like solar cell temperature, outlet temperature of air, electrical power, thermal power, electrical efficiency, thermal efficiency and overall efficiency are simulated and analyzed to evaluate the dynamic performance of the hybrid photovoltaic–thermal collector. It is found that the position of phase change material layer in the photovoltaic–thermal collector has a significant effect on the performance of the photovoltaic–thermal collector. The results indicate that upper phase change material mode in the photovoltaic–thermal collector can significantly improve the thermal and electrical performance of photovoltaic–thermal collector. It is found that overall efficiency of photovoltaic–thermal collector in ‘upper phase change material’ mode is 10.7% higher than that in ‘no phase change material’ mode. Further, for a photovoltaic–thermal collector with upper phase change material, it is verified that 3 cm

Development of a test device to characterize thermal protective performance of fabrics against hot steam and thermal radiation

International Nuclear Information System (INIS)

Su, Yun; Li, Jun

2016-01-01

Steam burns severely threaten the life of firefighters in the course of their fire-ground activities. The aim of this paper was to characterize thermal protective performance of flame-retardant fabrics exposed to hot steam and low-level thermal radiation. An improved testing apparatus based on ASTM F2731-11 was developed in order to simulate the routine fire-ground conditions by controlling steam pressure, flow rate and temperature of steam box. The thermal protective performance of single-layer and multi-layer fabric system with/without an air gap was studied based on the calibrated tester. It was indicated that the new testing apparatus effectively evaluated thermal properties of fabric in hot steam and thermal radiation. Hot steam significantly exacerbated the skin burn injuries while the condensed water on the skin’s surface contributed to cool down the skin tissues during the cooling. Also, the absorbed thermal energy during the exposure and the cooling was mainly determined by the fabric’s configuration, the air gap size, the exposure time and the existence of hot steam. The research provides a effective method to characterize the thermal protection of fabric in complex conditions, which will help in optimization of thermal protection performance of clothing and reduction of steam burn. (paper)

Millisecond photo-thermal process on significant improvement of supercapacitor’s performance

International Nuclear Information System (INIS)

Wang, Kui; Wang, Jixiao; Wu, Ying; Zhao, Song; Wang, Zhi; Wang, Shichang

2016-01-01

Graphical abstract: A high way for charge transfer is created by a millisecond photo-thermal process which could decrease contact resistance among nanomaterials and improve the electrochemical performances. - Highlights: • Improve conductivity among nanomaterials with a millisecond photo-thermal process. • The specific capacitance can increase about 25% with an photo-thermal process. • The circle stability and rate capability can be improved above 10% with photo-thermal process. • Provide a new way that create electron path to improve electrochemical performance. - Abstract: Supercapacitors fabricated with nanomaterials usually have high specific capacitance and excellent performance. However, the small size of nanomaterials renders a considerable limitation of the contact area among nanomaterials, which is harmful to charge carrier transfer. This fact may hinder the development and application of nanomaterials in electrochemical storage systems. Here, a millisecond photo-thermal process was introduced to create a charge carries transfer path to decrease the contact resistance among nanomaterials, and enhance the electrochemical performance of supercapacitors. Polyaniline (PANI) nanowire, as a model nanomaterial, was used to modify electrodes under different photo-thermal process conditions. The modified electrodes were characterized by scanning electronic microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and the results were analysed by equivalent circuit simulation. These results demonstrate that the photo-thermal process can alter the morphology of PANI nanowires, lower the charge transfer resistances and thus improve the performance of electrodes. The specific capacitance increase of the modified electrodes is about 25%. The improvement of the circle stability and rate capability are above 10%. To the best of our knowledge, this is the first attempt on research the effect of photo-thermal process on the conductivity

Military Deployment and Elementary Student Achievement

Science.gov (United States)

Phelps, Terri; Dunham, Mardis; Lyons, Robert

2010-01-01

This study investigated the impact that military deployment has upon academic achievement of elementary school students. TerraNova test scores of 137 fourth and fifth grade students in two elementary schools with a high proportion of military dependent children were examined for two consecutive years. Although the academic test performance fell…

Feasibility and Performance of the Microwave Thermal Rocket Launcher

OpenAIRE

Parkin, Kevin L. G.; Culick, Fred E. C.

2004-01-01

Beamed-energy launch concepts employing a microwave thermal thruster are feasible in principle, and microwave sources of sufficient power to launch tons into LEO already exist. Microwave thermal thrusters operate on an analogous principle to nuclear thermal thrusters, which have experimentally demonstrated specific impulses exceeding 850 seconds. Assuming such performance, simple application of the rocket equation suggests that payload fractions of 10% are possible for a single stage to orbit...

Sleep and Academic Performance in U.S. Military Training and Education Programs

Science.gov (United States)

Miller, Nita Lewis; Shattuck, Lawrence G.; Matsangas, Panagiotis; Dyche, Jeff

2008-01-01

This review examines the effects of military training regimes, which might include some degree of sleep deprivation, on sleep-wake schedules. We report a 4-year longitudinal study of sleep patterns of cadets at the United States Military Academy and the consequences of an extension of sleep from 6 to 8 hr per night at the United States Navy's…

Thermal preference, thermal tolerance and the thermal de-pendence of digestive performance in two Phrynocephalus lizards (Agamidae), with a review of species studied

OpenAIRE

Yanfu QU, Hong LI, Jianfang GAO, Xuefeng XU, Xiang JI

2011-01-01

We reported data on thermal preference, thermal tolerance and the thermal dependence of digestive performance for two Phrynocephalus lizards (P. frontalis and P. versicolor), and compared data among lizards so far studied worldwide. Mean values for selected body temperature (Tsel) and critical thermal maximum (CTMax) were greater in P. versicolor, whereas mean values for critical thermal minimum (CTMin) did not differ between the two species. The two lizards differed in food intake, but not i...

Military Strategy vs. Military Doctrine

DEFF Research Database (Denmark)

Barfoed, Jacob

2015-01-01

The article argues that while doctrine represents the more scientific side of warfare, strategy represents the artistic side. Existing doctrine will almost never meet the requirements for winning the next war; it is through the artistic application of generic peacetime doctrine to the specific st...... strategic and operational context, using doctrine as building blocks for a context specific military strategy, that the military commander outwits and defeats or coerces the adversary and achieves the military objectives....

Thermal Power Plant Performance Analysis

CERN Document Server

2012-01-01

The analysis of the reliability and availability of power plants is frequently based on simple indexes that do not take into account the criticality of some failures used for availability analysis. This criticality should be evaluated based on concepts of reliability which consider the effect of a component failure on the performance of the entire plant. System reliability analysis tools provide a root-cause analysis leading to the improvement of the plant maintenance plan.   Taking in view that the power plant performance can be evaluated not only based on  thermodynamic related indexes, such as heat-rate, Thermal Power Plant Performance Analysis focuses on the presentation of reliability-based tools used to define performance of complex systems and introduces the basic concepts of reliability, maintainability and risk analysis aiming at their application as tools for power plant performance improvement, including: ·         selection of critical equipment and components, ·         defini...

[Problems of military medical examination of military servicemen suffering from chronic obstructive pulmonary disease].

Science.gov (United States)

Chapliuk, A L; Brovkin, S G; Kal'manov, A S; Bulavin, V V

2015-02-01

The authors showed that at the present time military much more servicemen, suffering from obstructive pulmonary disease, may receive medical examination in outpatient conditions. Series of researches allow us to perform a medical examination on an outpatient basis. The calculation of the cost-effectiveness of health services to such patients during a military medical examination in the hospital and clinics was made. Savings during the examination in the clinic for 1 patient was 2829 rubbles.

Requirements for AMLCDs in U.S. military applications

Science.gov (United States)

Hopper, Darrel G.; Desjardins, Daniel D.

1995-06-01

Flat panel displays are fast becoming a significant source of more defense for less money. Military instruments have begun to use color active matrix liquid crystal displays (AMLCDs). This is the beginning of a significant transition from electromechanical, CRT. dichroic LCD, and electroluminescent display designs to the AMLCD designs. We have the opportunity with this new technology to establish common products capable of meeting user requirements for sunlight-readable, color and grayscale capable, high-sharpness high-pixel count, flat panel displays for military applications. The Wright Laboratory is leading the development of recommended best practice, draft guidance standard, and performance specifications for this new generation, the flat panel cockpit display generation, of display modules based on requirements for U.S. military aircraft and ground combat human system interfaces. These requirements are similar in many regards to those in both the civil aviation and automotive industries; accordingly, commonality with these civil applications is incorporated where possible, against the requirements for military combat applications. The performance requirement may be achieved by two approaches: militarization of displays made to low requirements of a large volume civil products manufacturer like Sharp or integration of displays made to high requirements by a niche market commercial vendor, like Optical Imaging Systems, Litton Systems Limited, ImageQuest Inc., and Planar Advanced Inc. teamed with Xerox PARC and Standish Industries. [Note that the niche market companies listed are commercial off-the shelf vendors, albeit for high requirement low volume customers.] Given that the performance specifications can be met for a particular military product by either approach, the choice is based on life cycle cost and a thin analysis based on initial costs alone is not acceptable as it ignores the fact that military product life cycles and procurements are 20-60 years

Young Australians’ Attitudes to the Military and Military Service

OpenAIRE

Ben Wadham; Grace Skrzypiec; Phillip Slee

2014-01-01

What are young Australians’ understandings of, and attitudes to, the military and military service? This article describes a pilot study of 320 young Australian university students’ attitudes to the military and military service during a time when Australia was engaged in the Afghanistan war. The main purpose of this study was to develop a survey instrument for further work in researching civil–military relations in Au...

Sleep as a component of the performance triad: the importance of sleep in a military population.

Science.gov (United States)

Lentino, Cynthia V; Purvis, Dianna L; Murphy, Kaitlin J; Deuster, Patricia A

2013-01-01

Sleep habits among military populations are problematic. Poor sleep hygiene occurs in parallel with the global increase in obesity and metabolic syndrome and contributes to a decrease in performance. The extent of sleep issues needs to be quantified to provide feedback for optimizing warfighter performance and readiness. This study assessed various health behaviors and habits of US Army Soldiers and their relationship with poor sleep quality by introducing a set of new questions into the Comprehensive Soldier and Family Fitness (CSF2) Global Assessment Tool (GAT). Subjects included 14,148 US Army Active, Reserve, and National Guard members (83.4% male) who completed the GAT, a self-report questionnaire that measures 4 fitness dimensions: social, family, emotional, and spiritual. Approximately 60 new questions, including ones on sleep quality, within the fifth CSF2 dimension (physical) were also answered. A sleep score was calculated from 2 questions validated in the Pittsburgh Insomnia Rating Scale (0 to 6). Poor sleepers (5-6) were significantly (Psleep quality in a group of military personnel and indicated significant associations between quality of sleep and physical performance, nutritional habits, measures of obesity, lifestyle behaviors and measures of psychosocial status. Targeted educational interventions and resources are needed to improve sleep patterns based on behaviors that can be most easily modified.

Thermal performance and efficiency of supercritical nuclear reactors

International Nuclear Information System (INIS)

Romney Duffey; Tracy Zhou; Hussam Khartabil

2009-01-01

The paper reviews the major advances and innovative aspects of the thermal performance of recent concepts for super-critical water-cooled nuclear reactors (SCWR). The concepts are based on the extensive experience in the thermal power industry with super and ultra-supercritical boilers and turbines. The challenges and goals of increased efficiency, reduced cost, enhanced safety and co-generation have been pursued over the last ten years, and have resulted both in viable concepts and a vibrant defined R and D effort. The supercritical concept has wide acceptance among industry, as it reflects standard engineering practices and current thermal plant technology that is being already deployed. The SCWR concept represents a continuous development of water-cooled reactor technology, which utilizes the best and latest advances made in the thermal power industry. (author)

Target acquisition performance : Effects of target aspect angle, dynamic imaging and signal processing

NARCIS (Netherlands)

Beintema, J.A.; Bijl, P.; Hogervorst, M.A.; Dijk, J.

2008-01-01

In an extensive Target Acquisition (TA) performance study, we recorded static and dynamic imagery of a set of military and civilian two-handheld objects at a range of distances and aspect angles with an under-sampled uncooled thermal imager. Next, we applied signal processing techniques including

Thermal resistances of air in cavity walls and their effect upon the thermal insulation performance

Energy Technology Data Exchange (ETDEWEB)

Bekkouche, S.M.A.; Cherier, M.K.; Hamdani, M.; Benamrane, N. [Application of Renewable Energies in Arid and Semi Arid Environments /Applied Research Unit on Renewable Energies/ EPST Development Center of Renewable Energies, URAER and B.P. 88, ZI, Gart Taam Ghardaia (Algeria); Benouaz, T. [University of Tlemcen, BP. 119, Tlemcen R.p. 13000 (Algeria); Yaiche, M.R. [Development Center of Renewable Energies, CDER and B.P 62, 16340, Route de l' Observatoire, Bouzareah, Algiers (Algeria)

2013-07-01

The optimum thickness in cavity walls in buildings is determined under steady conditions; the heat transfer has been calculated according to ISO 15099:2003. Two forms of masonry units are investigated to conclude the advantage of high thermal emissivity. The paper presents also some results from a study of the thermal insulation performance of air cavities bounded by thin reflective material layer 'eta = 0.05'. The results show that the most economical cavity configuration depends on the thermal emissivity and the insulation material used.

Composite Materials for Thermal Energy Storage: Enhancing Performance through Microstructures

Science.gov (United States)

Ge, Zhiwei; Ye, Feng; Ding, Yulong

2014-01-01

Chemical incompatibility and low thermal conductivity issues of molten-salt-based thermal energy storage materials can be addressed by using microstructured composites. Using a eutectic mixture of lithium and sodium carbonates as molten salt, magnesium oxide as supporting material, and graphite as thermal conductivity enhancer, the microstructural development, chemical compatibility, thermal stability, thermal conductivity, and thermal energy storage performance of composite materials are investigated. The ceramic supporting material is essential for preventing salt leakage and hence provides a solution to the chemical incompatibility issue. The use of graphite gives a significant enhancement on the thermal conductivity of the composite. Analyses suggest that the experimentally observed microstructural development of the composite is associated with the wettability of the salt on the ceramic substrate and that on the thermal conduction enhancer. PMID:24591286

Military legislation: explaining military officers' writing deficiencies

OpenAIRE

Borysov, Andrii

2016-01-01

Approved for public release; distribution is unlimited In performing jobs related to national security and defense, personnel must comply with rules and decisions communicated in the form of written legislation, which includes directives, memos, instructions, manuals, standard operating procedures, and reports. Incorrect understanding of legislative provisions may lead to disastrous consequences, making clear communication through these documents paramount. The vast majority of military of...

Estimation and optimization of thermal performance of evacuated tube solar collector system

Science.gov (United States)

Dikmen, Erkan; Ayaz, Mahir; Ezen, H. Hüseyin; Küçüksille, Ecir U.; Şahin, Arzu Şencan

2014-05-01

In this study, artificial neural networks (ANNs) and adaptive neuro-fuzzy (ANFIS) in order to predict the thermal performance of evacuated tube solar collector system have been used. The experimental data for the training and testing of the networks were used. The results of ANN are compared with ANFIS in which the same data sets are used. The R2-value for the thermal performance values of collector is 0.811914 which can be considered as satisfactory. The results obtained when unknown data were presented to the networks are satisfactory and indicate that the proposed method can successfully be used for the prediction of the thermal performance of evacuated tube solar collectors. In addition, new formulations obtained from ANN are presented for the calculation of the thermal performance. The advantages of this approaches compared to the conventional methods are speed, simplicity, and the capacity of the network to learn from examples. In addition, genetic algorithm (GA) was used to maximize the thermal performance of the system. The optimum working conditions of the system were determined by the GA.

Thermal performance of evacuated tube heat pipe solar collector

Science.gov (United States)

Putra, Nandy; Kristian, M. R.; David, R.; Haliansyah, K.; Ariantara, Bambang

2016-06-01

The high fossil energy consumption not only causes the scarcity of energy but also raises problems of global warming. Increasing needs of fossil fuel could be reduced through the utilization of solar energy by using solar collectors. Indonesia has the abundant potential for solar energy, but non-renewable energy sources still dominate energy consumption. With heat pipe as passive heat transfer device, evacuated tube solar collector is expected to heat up water for industrial and home usage without external power supply needed to circulate water inside the solar collector. This research was conducted to determine the performance of heat pipe-based evacuated tube solar collector as solar water heater experimentally. The experiments were carried out using stainless steel screen mesh as a wick material, and water and Al2O3-water 0.1% nanofluid as working fluid, and applying inclination angles of 0°, 15°, 30°, and 45°. To analyze the heat absorbed and transferred by the prototype, water at 30°C was circulated through the condenser. A 150 Watt halogen lamp was used as sun simulator, and the prototype was covered by an insulation box to obtain a steady state condition with a minimum affection of ambient changes. Experimental results show that the usage of Al2O3-water 0.1% nanofluid at 30° inclination angle provides the highest thermal performance, which gives efficiency as high as 0.196 and thermal resistance as low as 5.32 °C/W. The use of nanofluid as working fluid enhances thermal performance due to high thermal conductivity of the working fluid. The increase of the inclination angle plays a role in the drainage of the condensate to the evaporator that leads to higher thermal performance until the optimal inclination angle is reached.

Thermal-Hydraulic Performance of Scrubbing Nozzle Used for CFVS

Energy Technology Data Exchange (ETDEWEB)

Lee, Hyun Chul; Lee, Doo Yong; Jung, Woo Young; Lee, Jong Chan; Kim, Gyu Tae [FNC TECH, Yongin (Korea, Republic of)

2016-05-15

A Containment Filtered Venting System (CFVS) is the most interested device to mitigate a threat against containment integrity under the severe accident of nuclear power plant by venting with the filtration of the fission products. FNC technology and partners have been developed the self-priming scrubbing nozzle used for the CFVS which is based on the venturi effect. The thermal-hydraulic performances such as passive scrubbing water suction as well as pressure drop across the nozzle have been tested under various thermal-hydraulic conditions. The two types of test section have been built for testing the thermal-hydraulic performance of the self-priming scrubbing nozzle. Through the visualization loop, the liquid suction performance through the slit, pressure drop across the nozzle are measured. The passive water suction flow through the suction slit at the throat is important parameter to define the scrubbing performance of the self-priming scrubbing nozzle. The water suction flow is increased with the increase of the overhead water level at the same inlet gas flow. It is not so much changed with the change of inlet gas flow at the overhead water level.

Thermal performance measurements on ultimate heat sinks--cooling ponds

International Nuclear Information System (INIS)

Hadlock, R.K.; Abbey, O.B.

1977-12-01

The primary objective of the studies described is to obtain the requisite data, with respect to modeling requirements, to characterize thermal performance of heat sinks for nuclear facilities existing at elevated water temperatures in result of experiencing a genuinely large heat load and responding to meteorological influence. The data should reflect thermal performance for combinations leading to worst-case meteorological influence. A geothermal water retention basin has been chosen as the site for the first measurement program and data have been obtained in the first of several experiments scheduled to be performed there. These data illustrate the thermal and water budgets during episodes of cooling from an initially high pond water bulk temperature. Monitoring proceeded while the pond experienced only meteorological and seepage influence. The data are discussed and are presented as a data volume which may be used for calculation purposes. Suggestions for future measurement programs are stated with the intent to maintain and improve relevance to nuclear ultimate heat sinks while continuing to examine the performance of the analog geothermal pond. It is further suggested that the geothermal pond, with some modification, may be a suitable site for spray pond measurements

Performance analysis of a hybrid photovoltaic thermal solar air heater

International Nuclear Information System (INIS)

Othman, Mohd Yusof; Yatim, Baharudin; Abu Bakar, Mohd Nazari; Sopian, Kamaruzzaman

2006-01-01

A photovoltaic (PV/T) air heater is a collector that combines thermal and photovoltaic systems in one single hybrid generating unit. It generators both thermal and electrical energies simultaneously. A new design of a double-pass photovoltaic-thermal solar air collector with CPC and fins was successfully developed and fabricated at Universiti Kebangsaam Malaysia. This collector tested under actual environmental conditions to study its performance over a range of operating conditions. The test set-up, instrumentation and measurement are described further. It was found that the performance of the collector was in agreement with the theoretical prediction. Results of the outdoors test are presented and discussed(Author)

Experimental study on the thermal performance of a new type of thermal energy storage based on flat micro-heat pipe array

International Nuclear Information System (INIS)

Li, Feng-fei; Diao, Yan-hua; Zhao, Yao-hua; Zhu, Ting-ting; Liu, Jing

2016-01-01

Highlights: • A novel thermal energy storage based on flat micro-heat pipe array is proposed. • The thermal storage shows excellent thermal performance in the working process. • The novel thermal storage has the advantage of low flow resistance. - Abstract: The thermal performance of an air-based phase change storage unit is analyzed and discussed in this study. The thermal energy storage uses flat micro-heat pipe array (FMHPA) as the core heat transfer component and lauric acid as phase change material (PCM). An experimental system is devised to test the heat storage–release property of the storage unit under different inlet temperatures and flow rates of the heat transfer medium. The performance of the storage unit and the melting/solidification curves of the phase change material are obtained based on extensive experimental data. Experimental results indicate that the flat micro-heat pipe array exhibits excellent temperature uniformity in the heat storage–release process, and the performance of the storage unit is efficient and steady.

Thermal Imaging Performance of TIR Onboard the Hayabusa2 Spacecraft

Science.gov (United States)

Arai, Takehiko; Nakamura, Tomoki; Tanaka, Satoshi; Demura, Hirohide; Ogawa, Yoshiko; Sakatani, Naoya; Horikawa, Yamato; Senshu, Hiroki; Fukuhara, Tetsuya; Okada, Tatsuaki

2017-07-01

The thermal infrared imager (TIR) is a thermal infrared camera onboard the Hayabusa2 spacecraft. TIR will perform thermography of a C-type asteroid, 162173 Ryugu (1999 JU3), and estimate its surface physical properties, such as surface thermal emissivity ɛ , surface roughness, and thermal inertia Γ, through remote in-situ observations in 2018 and 2019. In prelaunch tests of TIR, detector calibrations and evaluations, along with imaging demonstrations, were performed. The present paper introduces the experimental results of a prelaunch test conducted using a large-aperture collimator in conjunction with TIR under atmospheric conditions. A blackbody source, controlled at constant temperature, was measured using TIR in order to construct a calibration curve for obtaining temperatures from observed digital data. As a known thermal emissivity target, a sandblasted black almite plate warmed from the back using a flexible heater was measured by TIR in order to evaluate the accuracy of the calibration curve. As an analog target of a C-type asteroid, carbonaceous chondrites (50 mm × 2 mm in thickness) were also warmed from the back and measured using TIR in order to clarify the imaging performance of TIR. The calibration curve, which was fitted by a specific model of the Planck function, allowed for conversion to the target temperature within an error of 1°C (3σ standard deviation) for the temperature range of 30 to 100°C. The observed temperature of the black almite plate was consistent with the temperature measured using K-type thermocouples, within the accuracy of temperature conversion using the calibration curve when the temperature variation exhibited a random error of 0.3 °C (1σ ) for each pixel at a target temperature of 50°C. TIR can resolve the fine surface structure of meteorites, including cracks and pits with the specified field of view of 0.051°C (328 × 248 pixels). There were spatial distributions with a temperature variation of 3°C at the setting

MATLAB Simulation of Photovoltaic and Photovoltaic/Thermal Systems Performance

Science.gov (United States)

Nasir, Farah H. M.; Husaini, Yusnira

2018-03-01

The efficiency of the photovoltaic reduces when the photovoltaic cell temperature increased due to solar irradiance. One solution is come up with the cooling system photovoltaic system. This combination is forming the photovoltaic-thermal (PV/T) system. Not only will it generate electricity also heat at the same time. The aim of this research is to focus on the modeling and simulation of photovoltaic (PV) and photovoltaic-thermal (PV/T) electrical performance by using single-diode equivalent circuit model. Both PV and PV/T models are developed in Matlab/Simulink. By providing the cooling system in PV/T, the efficiency of the system can be increased by decreasing the PV cell temperature. The maximum thermal, electrical and total efficiency values of PV/T in the present research are 35.18%, 15.56% and 50.74% at solar irradiance of 400 W/m2, mass flow rate of 0.05kgs-1 and inlet temperature of 25 °C respectively has been obtained. The photovoltaic-thermal shows that the higher efficiency performance compared to the photovoltaic system.

Quantification of thermal damage in skin tissue

Institute of Scientific and Technical Information of China (English)

Xu Feng; Wen Ting; Lu Tianjian; Seffen Keith

2008-01-01

Skin thermal damage or skin burns are the most commonly encountered type of trauma in civilian and military communities. Besides, advances in laser, microwave and similar technologies have led to recent developments of thermal treatments for disease and damage involving skin tissue, where the objective is to induce thermal damage precisely within targeted tissue structures but without affecting the surrounding, healthy tissue. Further, extended pain sensation induced by thermal damage has also brought great problem for burn patients. Thus, it is of great importance to quantify the thermal damage in skin tissue. In this paper, the available models and experimental methods for quantification of thermal damage in skin tissue are discussed.

Composite materials for thermal energy storage: enhancing performance through microstructures.

Science.gov (United States)

Ge, Zhiwei; Ye, Feng; Ding, Yulong

2014-05-01

Chemical incompatibility and low thermal conductivity issues of molten-salt-based thermal energy storage materials can be addressed by using microstructured composites. Using a eutectic mixture of lithium and sodium carbonates as molten salt, magnesium oxide as supporting material, and graphite as thermal conductivity enhancer, the microstructural development, chemical compatibility, thermal stability, thermal conductivity, and thermal energy storage performance of composite materials are investigated. The ceramic supporting material is essential for preventing salt leakage and hence provides a solution to the chemical incompatibility issue. The use of graphite gives a significant enhancement on the thermal conductivity of the composite. Analyses suggest that the experimentally observed microstructural development of the composite is associated with the wettability of the salt on the ceramic substrate and that on the thermal conduction enhancer. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Thermal and Hygric Expansion of High Performance Concrete

OpenAIRE

J. Toman; R. Černý

2001-01-01

The linear thermal expansion coefficient of two types of high performance concrete was measured in the temperature range from 20 °C to 1000 °C, and the linear hygric expansion coefficient was determined in the moisture range from dry material to saturation water content. Comparative methods were applied for measurements of both coefficients. The experimental results show that both the effect of temperature on the values of linear thermal expansion coefficients and the effect of moisture on th...

Optimal thermal-hydraulic performance for helium-cooled divertors

International Nuclear Information System (INIS)

Izenson, M.G.; Martin, J.L.

1996-01-01

Normal flow heat exchanger (NFHX) technology offers the potential for cooling divertor panels with reduced pressure drops (<0.5% Δp/p), reduced pumping power (<0.75% pumping/thermal power), and smaller duct sizes than conventional helium heat exchangers. Furthermore, the NFHX can easily be fabricated in the large sizes required for divertors in large tokamaks. Recent experimental and computational results from a program to develop NFHX technology for divertor coolings using porous metal heat transfer media are described. We have tested the thermal and flow characteristics of porous metals and identified the optimal heat transfer material for the divertor heat exchanger. Methods have been developed to create highly conductive thermal bonds between the porous material and a solid substrate. Computational fluid dynamics calculations of flow and heat transfer in the porous metal layer have shown the capability of high thermal effectiveness. An 18-kW NFHX, designed to meet specifications for the international Thermonuclear Experimental Reactor divertor, has been fabricated and tested for thermal and flow performance. Preliminary results confirm design and fabrication methods. 11 refs., 12 figs., 1 tab

Thermal performance of plate-type loop thermosyphon at sub-atmospheric pressures

International Nuclear Information System (INIS)

Tsoi, Vadim; Chang, Shyy Woei; Chiang Kuei Feng; Huang, Chuan Chin

2011-01-01

This experimental study examines the thermal performance of a newly devised plate-type two-phase loop thermosyphon with cooling applications to electronic boards of telecommunication systems. The evaporation section is configured as the inter-connected multi channels to emulate the bridging boiling mechanism in pulsating thermosyphon. Two thermosyphon plates using water as the coolant with filling ratios (FR) of 0.22 and 0.32 are tested at sub-atmospheric pressures. The vapor-liquid flow images as well as the thermal resistances and effective spreading thermal conductivities are individually measured for each thermosyphon test plate at various heating powers. The high-speed digital images of the vapor-liquid flow structures reveal the characteristic boiling phenomena and the vapor-liquid circulation in the vertical thermosyphon plate, which assist to explore the thermal physics for this type of loop thermosyphon. The bubble agglomeration and pumping action in the inter-connected boiling channels take place at metastable non-equilibrium conditions, leading to the intermittent slug flows with a pulsation character. Such hybrid loop-pulsating thermosyphon permits the vapor-liquid circulation in the horizontal plate. Thermal resistances and spreading thermal conductivities detected from the present thermosyphon plates; the vapor chamber flat plate heat pipe and the copper plate at free and forced convective cooling conditions with both vertical and horizontal orientations are cross-examined. In most telecommunication systems and units, the electrical boards are vertical so that the thermal performance data on the vertical thermosyphon are most relevant to this particular application. - Highlights: → We examine thermal performances of plate-type loop thermosyphon. → Thermal resistances and spreading conductivities are examined. → Bubble agglomeration in inter-connected boiling channels generates intermittent slug flows with pulsations. → Boiling instability

The influence of weather on the thermal performance of solar heating systems

DEFF Research Database (Denmark)

Andersen, Elsa; Furbo, Simon; Shah, Louise Jivan

2003-01-01

. The investigation is based on calculations with validated models. Solar heating systems with different solar collector types, heat storage volumes and solar fractions are included in the investigation. The yearly solar radiation varies with approximately 20 % in the period from 1990 until 2002. The calculations......The influence of weather on the thermal performance of solar combi systems, solar domestic hot water systems and solar heating plants is investigated. The investigation is based on weather data from the Danish Design Reference Year, DRY and weather data measured for a period from 1990 until 2002...... show that the thermal performance of the investigated systems varies due to the weather variation. The variation of the yearly thermal performance of a solar heating plant is about 40 % while the variation of the yearly thermal performance of a solar domestic hot water system is about 30...

Syria’s Military Capabilities and Options for Military Intervention

DEFF Research Database (Denmark)

Pradhan-Blach, Flemming

2012-01-01

This background paper does not endorse any military action towards Syria. The document does not reflect or express any official Danish policy or a position of the University of Copenhagen or the Centre for Military Studies. The purpose of this paper is to briefly describe military capabilities...... and options in order to provide a factual background for the ongoing discussion on possible military intervention in the Syrian conflict and Denmark’s possible participation in such an intervention. The paper is primarily based on the Military Balance published by the International Institute for Strategic...

Consortium for Health and Military Performance and American College of Sports Medicine consensus paper on extreme conditioning programs in military personnel.

Science.gov (United States)

Bergeron, Michael F; Nindl, Bradley C; Deuster, Patricia A; Baumgartner, Neal; Kane, Shawn F; Kraemer, William J; Sexauer, Lisa R; Thompson, Walter R; O'Connor, Francis G

2011-01-01

A potential emerging problem associated with increasingly popularized extreme conditioning programs (ECPs) has been identified by the military and civilian communities. That is, there is an apparent disproportionate musculoskeletal injury risk from these demanding programs, particularly for novice participants, resulting in lost duty time, medical treatment, and extensive rehabilitation. This is a significant and costly concern for the military with regard to effectively maintaining operational readiness of the Force. While there are certain recognized positive aspects of ECPs that address a perceived and/or actual unfulfilled conditioning need for many individuals and military units, these programs have limitations and should be considered carefully. Moreover, certain distinctive characteristics of ECPs appear to violate recognized accepted standards for safely and appropriately developing muscular fitness and are not uniformly aligned with established and accepted training doctrine. Accordingly, practical solutions to improve ECP prescription and implementation and reduce injury risk are of paramount importance.

Comparative performance study of smart structure for thermal microactuators

Science.gov (United States)

Yahya, Zulkarnain; Johar, Muhammad Akmal

2017-04-01

Thermal microactuator is one of earliest types of microactuators. Typical thermal actuators are in the form of Bimorph and Chevron structures. A bimorph thermal actuator has a complex movement direction, in arc motion and thus it is not feasible in the most MEMS designs. While Chevron actuator has a tendency to produce an off-plane movement which lead to low precision in lateral movement. A new thermal actuator design in the form of serpentine structures shows promising feature to have better performances in terms of more predictive lateral movement with smaller off-plane displacement. In MEMS chip design, areas play a critical role as it will impact with the cost of the final product. In this study, four different structures of thermal actuator were simulated using ANSYS v15. Three different set of area sizes which are 240 µm x 1000 µm, 240 µm x 1500 µm and 240 µm x 2000 µm have been analyzed. All four structures were named as Serpentine01, Serpentine02, Bimorph and Chevron. The data with regards to temperature produced by the structure and z-axis directional deformation were collected and analyzed. This paper reported the investigation result of comparison between these three types of thermal actuator structures design with a given area. From all of the result obtained, it is shown that the area 240 µm x 1500 µm showed a well balance performance in term of huge deformations and low power consumption. The Serpentine01 structure produced 16.7 µm deformation at 4mA of current. The results shows the potential of Serpentine01 structure as a new candidate for thermal microactuator for MEMS applications.

Genetic analysis of reproductive performance of Frieswal cattle at Military Farm, Ambala

Directory of Open Access Journals (Sweden)

Jagdeep Kumar

2015-09-01

Full Text Available Aim: This study was carried out to investigate the genetic analysis of reproductive performance of Frieswal cattle at Military Farm, Ambala. Materials and Methods: A total number of 3005 lactation records of 1147 Frieswal cows over a period of 15 years extending from 1993 to 2007 were used to study at Military Dairy Farm, Ambala. The study period was divided into 5 period of 3 years each. The average performances of reproduction traits, effect of genetic and non-genetic factors were analyzed, and estimation of genetic and phenotypic parameters of reproduction traits was undertaken. Results: The age at first calving (AFC differed significantly across the periods of calving. The AFC was lowest during the third period (1999-2001 and longest in the first period (1993-95. The effect of season and period of calving, lactation order and regression of AFC on dry period, calving interval and service period was highly significant. The effect of sire was non-significant. The heritability estimates were low for almost all the traits under study. The service period had a high genetic correlation with dry period and calving interval. The dry period also found to have a low genetic correlation with calving interval in Frieswal cows. Service period had a high phenotypic correlation with dry period and very high with a calving interval. The phenotypic correlation between the dry period and calving interval was recognized high. Conclusions: Low heritability estimate for the reproduction traits indicates that there is a very little additive genetic variance in these traits, and individual selection will not be helpful for improving them. Improvement may be brought through better feeding and management of cows by reducing the environmental variability.

Photovoltaic thermal module concepts and their performance analysis: A review

International Nuclear Information System (INIS)

Hasan, M. Arif; Sumathy, K.

2010-01-01

This paper presents a review of the available literature covering the latest module aspects of different photovoltaic/thermal (PV/T) collectors and their performances in terms of electrical as well as thermal output. The review covers detailed description of flat-plate and concentrating PV/T systems, using liquid or air as the working fluid, numerical model analysis, experimental work and qualitative evaluation of thermal and electrical output. Also an in-depth review on the performance parameters such as, optimum mass flow rate, PV/T dimensions, air channel geometry is presented in this study. Based on the thorough review, it is clear that PV/T modules are very promising devices and there exists lot of scope to further improve their performances. Appropriate recommendations are made which will aid PV/T systems to improve their efficiency and reducing their cost, making them more competitive in the present market. (author)

Study on thermal performance and margins of BWR fuel elements

International Nuclear Information System (INIS)

Stosic, Zoran

1999-01-01

This paper contributes to developing a methodology of predicting and analyzing thermal performance and margins of Boiling Water Reactor (BWR) fuel assemblies under conditions of reaching high quality Boiling Crisis and subsequent post-dryout thermal hydraulics causing temperature excursion of fuel cladding. Operational margins against dryout and potential for increasing fuel performance with appropriate benefits are discussed. The philosophy of modeling with its special topics are demonstrated on the HECHAN (HEated CHannel ANalyzer) model as the state-of-art for thermal-hydraulics analysis of BWR fuel assemblies in pre- and post-dryout two-phase flow regimes. The scope of further work either being or has to be performed concerning implementation of new physical aspects, including domain extension of HECHAN model applications to the Pressurized Water Reactors (PWRs), is discussed. Finally, a comprehensive overview of the literature dealing with development of the model is given. (author)

Photovoltaic thermal module concepts and their performance analysis: A review

Energy Technology Data Exchange (ETDEWEB)

Hasan, M. Arif; Sumathy, K. [Department of Mechanical Engineering, North Dakota State University, Fargo, ND (United States)

2010-09-15

This paper presents a review of the available literature covering the latest module aspects of different photovoltaic/thermal (PV/T) collectors and their performances in terms of electrical as well as thermal output. The review covers detailed description of flat-plate and concentrating PV/T systems, using liquid or air as the working fluid, numerical model analysis, experimental work and qualitative evaluation of thermal and electrical output. Also an in-depth review on the performance parameters such as, optimum mass flow rate, PV/T dimensions, air channel geometry is presented in this study. Based on the thorough review, it is clear that PV/T modules are very promising devices and there exists lot of scope to further improve their performances. Appropriate recommendations are made which will aid PV/T systems to improve their efficiency and reducing their cost, making them more competitive in the present market. (author)

14 CFR 61.73 - Military pilots or former military pilots: Special rules.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Military pilots or former military pilots... Ratings and Pilot Authorizations § 61.73 Military pilots or former military pilots: Special rules. (a... a disciplinary action involving aircraft operations, a U.S. military pilot or former military pilot...

Converting Resources from Military to Non-military Uses

OpenAIRE

Jurgen Brauer; John Tepper Marlin

1992-01-01

As a proportion of gross national product, U.S. military spending has declined steadily since the mid-1980s. The end of the Cold War has given rise to calls for even more cuts in military spending. In early 1992, President George Bush proposed to reduce military spending by 3 percent per year, in real dollars, for the next five years. The Democratic leadership in the House of Representatives countered with a plan calling for substantially deeper cuts. Any substantial changes in military expen...

Low-stress photosensitive polyimide suspended membrane for improved thermal isolation performance

Science.gov (United States)

Fan, J.; Xing, R. Y.; Wu, W. J.; Liu, H. F.; Liu, J. Q.; Tu, L. C.

2017-11-01

In this paper, we introduce a method of isolating thermal conduction from silicon substrate for accommodating thermal-sensitive micro-devices. This method lies in fabrication of a low-stress photosensitive polyimide (PSPI) suspension structure which has lower thermal conductivity than silicon. First, a PSPI layer was patterned on a silicon wafer and hard baked. Then, a cavity was etched from the backside of the silicon substrate to form a membrane or a bridge-shape PSPI structure. After releasing, a slight deformation of about 20 nm was observed in the suspended structures, suggesting ultralow residual stress which is essential for accommodating micro-devices. In order to investigate the thermal isolation performance of the suspended PSPI structures, micro Pirani vacuum gauges, which are thermal-sensitive, had been fabricated on the PSPI structures. The measurement results illustrated that the Pirani gauges worked as expected in the range from 1- 470 Pa. Moreover, the results of the Pirani gauges based on the membrane and bridge structures were comparable, indicating that the commonly used bridge-shape structure for further reducing thermal conduction was unnecessary. Due to the excellent thermal isolation performance of PSPI, the suspended PSPI membrane is promising to be an outstanding candidate for thermal isolation applications.

Performance Evaluation Facility for Fire Fighting Thermal Imager

International Nuclear Information System (INIS)

Kim, Sung Chan; Amon, Francine; Hamins, Anthony

2007-01-01

The present study investigates the characteristics of obscuring media inside an optical smoke cell, which is a bench-scale testing facility for the evaluation of thermal imaging cameras used by fire fighters. Light extinction coefficient and visibility through the smoke cell is characterized by the measured laser transmittance. The laser transmittance along the axial direction of the smoke cell is relatively uniform at upper and lower part for various air/fuel volume flow rate. Contrast level based image quality of visible CCD camera through the smoke cell is compared with that of thermal imaging camera. The optical smoke cell can be used as well-controlled and effective laboratory-scale test apparatus to evaluate the performance of thermal imaging camera for fire fighting application

Thermal performance analysis of a phase change thermal storage unit for space heating

Energy Technology Data Exchange (ETDEWEB)

Halawa, E.; Saman, W. [Institute for Sustainable Systems and Technologies School of Advanced Manufacturing and Mechanical Engineering, University of South Australia, Mawson Lakes SA 5095 (Australia)

2011-01-15

This paper presents the results of a comprehensive numerical study on the thermal performance of an air based phase change thermal storage unit (TSU) for space heating. The unit is designed for integration into space heating and cooling systems. The unit consists of a number of one dimensional phase change material (PCM) slabs contained in a rectangular duct where air passes between the slabs. The numerical analysis was based on an experimentally validated model. A parametric study has been carried out including the study on the effects of charge and discharge temperature differences, air mass flow rate, slab thicknesses, air gaps and slab dimensions on the air outlet temperatures and heat transfer rates of the thermal storage unit. The paper introduces and discusses quantities called charge and discharge temperature differences which play an important role in the melting and freezing processes. (author)

Development of Mitsubishi high thermal performance grid 1 - CFD applicability for thermal hydraulic design

International Nuclear Information System (INIS)

Ikeda, K.; Hoshi, M.

2001-01-01

Mitsubishi applied the Computational Fluid Dynamics (CFD) evaluation method for designing of the new lower pressure loss and higher DNB performance grid spacer. Reduction of pressure loss of the grid has been estimated by CFD. Also, CFD has been developed as a design tool to predict the coolant mixing ability of vane structures, that is to compare the relative peak spot temperatures around fuel rods at the same heat flux condition. These evaluations have been reflected to the new grid spacer design. The prototype grid was manufactured and some flow tests were performed to examine the thermal hydraulic performance, which were predicted by CFD. The experimental data of pressure loss was in good agreement with CFD prediction. The CFD prediction of flow behaviors at downstream of the mixing vanes was verified by detail cross-flow measurements at rod gaps by the rod LDV system. It is concluded that the applicability of the CFD evaluation method for the thermal hydraulic design of the grid is confirmed. (authors)

Military radiobiology: A perspective

International Nuclear Information System (INIS)

Walker, R.I.; Conklin, J.J.

1987-01-01

Acute medical consequences affecting military personnel fall into two major classes: early events affecting performance and later more lethal events associated with single and combined injuries. If cells survive the radiation insult, they have the capability for repair. But the patient must survive fluid loss, infection, and bleeding defects until this can occur. Although no one can ever eliminate the incomprehensible destruction of human life associated with the use of nuclear weapons, significant medical advances can be achieved that will increase the performance and recovery of persons exposed to these weapons. Furthermore, these medical advances will go far toward improving the life and functioning of persons undergoing radiotherapy, trauma, accidental exposures, or a variety of other clinical situations. In the near future, the military battlefield will move into another dimension - space. Once outside the geomagnetic shield of the earth, military prsonnel will be exposed to a formidable array of new radiations. Among the new radiations will be high solar energy, solar particles and flares, and heavy nuclei from galactic cosmic arrays. Associated stresses will be microgravity, vibration, and isolation. To protect man in these new environments will truly challenge our ingenuity. This book looks at various medical consequences we face as a result of nuclear energy

Thermal performance of a multiple PCM thermal storage unit for free cooling

International Nuclear Information System (INIS)

Mosaffa, A.H.; Infante Ferreira, C.A.; Talati, F.; Rosen, M.A.

2013-01-01

Highlights: ► Numerical analysis on the performance of a thermal storages as free cooling system. ► Employing multiple PCMs to enhance heat transfer rate in thermal storages. ► Using an effective heat capacity method, the phase change parameters are determined. ► The effect of the slabs size and air channel thickness on COP is investigated. - Abstract: As demand for refrigeration and air conditioning increased during the last decade, the opportunities have expanded for using thermal energy storage (TES) systems in an economically advantageous manner in place of conventional cooling plants. Many cool storage systems use phase change materials (PCMs) and achieve peak load shifting in buildings. This work presents numerical investigations of the performance enhancement of a free cooling system using a TES unit employing multiple PCMs. The TES unit is composed of a number of rectangular channels for the flowing heat transfer fluid, separated by PCM slabs. Using the effective heat capacity method, the melting and solidification of the PCM is solved. The forced convective heat transfer inside the channels is analyzed by solving the energy equation, which is coupled with the heat conduction equation in the container wall. The effect of design parameters such as PCM slab length, thickness and fluid passage gap on the storage performance is also investigated using an energy based optimization. The results show that a system which can guarantee comfort conditions for the climate of Tabriz, Iran has an optimum COP of 7.0. This could be achieved by a combination of CaCl 2 ·6H 2 O with RT25 with the optimum air channel thickness of 3.2 mm, length of 1.3 m and PCM slab thickness of 10 mm

Is long term creatine and glutamine supplementation effective in enhancing physical performance of military police officers?

Science.gov (United States)

da Silveira, Celismar Lázaro; de Souza, Thiago Siqueira Paiva; Batista, Gilmário Ricarte; de Araújo, Adenilson Targino; da Silva, Júlio César Gomes; de Sousa, Maria do Socorro Cirilo; Marta, Carlos; Garrido, Nuno Domingo

2014-09-29

The objective of this study was to analyze the effect of supplementation with creatine and glutamine on physical fitness of military police officers. Therefore, an experimental double blind study was developed, with the final sample composed by 32 men randomly distributed into three groups: a group supplemented with creatine (n=10), glutamine (n=10) and a placebo group (n=12) and evaluated in three distinct moments, in an interval of three months (T1, T2 and T3). The physical training had a weekly frequency of 5 sessions × 90 min, including strength exercises, local muscular resistance, flexibility and both aerobic and anaerobic capacity. After analyzing the effect of time, group and interaction (group × time) for measures that indicated the physical capabilities of the subjects, a significant effect of time for the entire variable was identified (p0,05). In face of the results it was concluded that supplementation with creatine and glutamine showed no ergogenic effect on physical performance in military police officers.

Yearly thermal performances of solar heating plants in Denmark – Measured and calculated

DEFF Research Database (Denmark)

Furbo, Simon; Dragsted, Janne; Perers, Bengt

2018-01-01

The thermal performance of solar collector fields depends mainly on the mean solar collector fluid temperature of the collector field and on the solar radiation. For Danish solar collector fields for district heating the measured yearly thermal performances per collector area varied in the period...... 2012–2016 between 313 kWh/m2 and 577 kWh/m2, with averages between 411 kWh/m2 and 463 kWh/m2. The percentage difference between the highest and lowest measured yearly thermal performance is about 84%. Calculated yearly thermal performances of typically designed large solar collector fields at six...... different locations in Denmark with measured weather data for the years 2002–2010 vary between 405 kWh/m2 collector and 566 kWh/m2 collector, if a mean solar collector fluid temperature of 60 °C is assumed. This corresponds to a percentage difference between the highest and lowest calculated yearly thermal...

Thermal performance of a phase change material on a nickel-plated surface

International Nuclear Information System (INIS)

Nurmawati, M.H.; Siow, K.S.; Rasiah, I.J.

2004-01-01

Thermal control becomes increasingly vital with IC chips becoming faster and smaller. The need to keep chips within acceptable operating temperatures is a growing challenge. Thermal interface materials (TIM) form the interfaces that improve heat transfer from the heat-generating chip to the heat dissipating thermal solution. One of the most commonly used materials in today's electronics industry is phase change material (PCM). Typically, the heat spreader is a nickel-plated copper surface. The compatibility of the PCM to this surface is crucial to the performance of the TIM. In this paper, we report on the performance of this interface. To that end, an instrument to suitably measure critical parameters, like the apparent and contact thermal resistance of the TIM, is developed according to the ASTM D5470 and calibrated. A brief theory of TIM is described and the properties of the PCM were investigated using the instrument. Thermal resistance measurements were made to investigate the effects of physical parameters like pressure, temperature and supplied power on the thermal performance of the material on nickel-plated surface. Conclusions were drawn on the effectiveness of the interface and their application in IC packages

Performance monitoring pavements with thermal segregation in Texas.

Science.gov (United States)

2012-04-01

This project conducted work to investigate the performance of asphalt surface mixtures that exhibited : thermal segregation during construction. From 2004 to 2009, a total of 14 construction projects were : identified for monitoring. Five of these pr...

System performance modeling of extreme ultraviolet lithographic thermal issues

International Nuclear Information System (INIS)

Spence, P. A.; Gianoulakis, S. E.; Moen, C. D.; Kanouff, M. P.; Fisher, A.; Ray-Chaudhuri, A. K.

1999-01-01

Numerical simulation is used in the development of an extreme ultraviolet lithography Engineering Test Stand. Extensive modeling was applied to predict the impact of thermal loads on key lithographic parameters such as image placement error, focal shift, and loss of CD control. We show that thermal issues can be effectively managed to ensure that their impact on lithographic performance is maintained within design error budgets. (c) 1999 American Vacuum Society

Shrinking the Civil-Military Divide: A Military Perspective

Science.gov (United States)

2015-04-13

behavior and rights, the values of the military are different and unique. Senior military officers highlight the importance of understanding the...Examples include on-base housing, shopping , schools, children’s sports leagues, and community and social events such as concerts, comedy shows, and movies... mall , a sporting event, or the movies provides a simple, 16 Skelton, “The Civil-Military Gap

Hydraulic performance of compacted clay liners under simulated daily thermal cycles.

Science.gov (United States)

Aldaeef, A A; Rayhani, M T

2015-10-01

Compacted clay liners (CCLs) are commonly used as hydraulic barriers in several landfill applications to isolate contaminants from the surrounding environment and minimize the escape of leachate from the landfill. Prior to waste placement in landfills, CCLs are often exposed to temperature fluctuations which can affect the hydraulic performance of the liner. Experimental research was carried out to evaluate the effects of daily thermal cycles on the hydraulic performance of CCLs under simulated landfill conditions. Hydraulic conductivity tests were conducted on different soil specimens after being exposed to various thermal and dehydration cycles. An increase in the CCL hydraulic conductivity of up to one order of magnitude was recorded after 30 thermal cycles for soils with low plasticity index (PI = 9.5%). However, medium (PI = 25%) and high (PI = 37.2%) plasticity soils did not show significant hydraulic deviation due to their self-healing potential. Overlaying the CCL with a cover layer minimized the effects of daily thermal cycles, and maintained stable hydraulic performance in the CCLs even after exposure to 60 thermal cycles. Wet-dry cycles had a significant impact on the hydraulic aspect of low plasticity CCLs. However, medium and high plasticity CCLs maintained constant hydraulic performance throughout the test intervals. The study underscores the importance of protecting the CCL from exposure to atmosphere through covering it by a layer of geomembrane or an interim soil layer. Copyright © 2015 Elsevier Ltd. All rights reserved.

Thermal buffering performance of composite phase change materials applied in low-temperature protective garments

Science.gov (United States)

Yang, Kai; Jiao, Mingli; Yu, Yuanyuan; Zhu, Xueying; Liu, Rangtong; Cao, Jian

2017-07-01

Phase change material (PCM) is increasingly being applied in the manufacturing of functional thermo-regulated textiles and garments. This paper investigated the thermal buffering performance of different composite PCMs which are suitable for the application in functional low-temperature protective garments. First, according to the criteria selecting PCM for functional textiles/garments, three kinds of pure PCM were selected as samples, which were n-hexadecane, n-octadecane and n-eicosane. To get the adjustable phase change temperature range and higher phase change enthalpy, three kinds of composite PCM were prepared using the above pure PCM. To evaluate the thermal buffering performance of different composite PCM samples, the simulated low-temperature experiments were performed in the climate chamber, and the skin temperature variation curves in three different low temperature conditions were obtained. Finally composite PCM samples’ thermal buffering time, thermal buffering capacity and thermal buffering efficiency were calculated. Results show that the comprehensive thermal buffering performance of n-octadecane and n-eicosane composite PCM is the best.

Heat transfer and thermal storage performance of an open thermosyphon type thermal storage unit with tubular phase change material canisters

International Nuclear Information System (INIS)

Wang, Ping-Yang; Hu, Bo-Wen; Liu, Zhen-Hua

2015-01-01

Highlights: • A novel open heat pipe thermal storage unit is design to improve its performance. • Mechanism of its operation is phase-change heat transfer. • Tubular canisters with phase change material were placed in thermal storage unit. • Experiment and analysis are carried out to investigate its operation properties. - Abstract: A novel open thermosyphon-type thermal storage unit is presented to improve design and performance of heat pipe type thermal storage unit. In the present study, tubular canisters filled with a solid–liquid phase change material are vertically placed in the middle of the thermal storage unit. The phase change material melts at 100 °C. Water is presented as the phase-change heat transfer medium of the thermal storage unit. The tubular canister is wrapped tightly with a layer of stainless steel mesh to increase the surface wettability. The heat transfer mechanism of charging/discharging is similar to that of the thermosyphon. Heat transfer between the heat resource or cold resource and the phase change material in this device occurs in the form of a cyclic phase change of the heat-transfer medium, which occurs on the surface of the copper tubes and has an extremely high heat-transfer coefficient. A series of experiments and theoretical analyses are carried out to investigate the properties of the thermal storage unit, including power distribution, start-up performance, and temperature difference between the phase change material and the surrounding vapor. The results show that the whole system has excellent heat-storage/heat-release performance

Entransy analysis on the thermal performance of flat plate solar air collectors

Institute of Scientific and Technical Information of China (English)

Jie Deng; Xudong Yang; Yupeng Xu; Ming Yang

2017-01-01

Based on the thermo-electric analogy (the so-called thermal entransy analysis), the unified airside convective heat transfer coefficient for different sorts of flat plate solar air collectors (FPSACs) is identified in terms of colector aperture area. In addition, the colector thermodynamic characteristic matching coefficient is defined to depict the matching property of collector thermal performance between the collector airside heat transfer and the total heat losses. It is found that the airside convective heat transfer coefficient can be experimentally determined by collector thermal performance test method to compare the airside thermal performances of FPSACs with different types of airflow structures. Moreover, the smaler the colector thermodynamic characteristic matching coefficient is, the better the thermodynamic perfect degree of a FPSAC is. The minimum limit value of the collector thermodynamic matching coefficient is close to zero but it can not vanish in practical engineering. Parameter sensitivity analysis on the total entransy dissipation and the entransy increment of a general FPSAC is also undertaken. The results indicate that the effective way of decreasing total entransy dissipation and enhancing the useful entransy increment is improving the efficiency intercept of the FPSAC. This is equivalent to the cognition result of thermal analysis. However, the evaluation indices identified by the thermal entransy analysis can not be extracted by singular thermal analysis.

Performance of a thermal neutron radiographic system using imaging plates

International Nuclear Information System (INIS)

Silvani, Maria Ines; Almeida, Gevaldo L. de; Furieri, Rosanne; Lopes, Ricardo T.

2009-01-01

A performance evaluation of a neutron radiographic system equipped with a thermal neutron sensitive imaging plate has been undertaken. It includes the assessment of spatial resolution, linearity, dynamic range and the response to exposure time, as well as a comparison of these parameters with the equivalent ones for neutron radiography employing conventional films and a gadolinium foil as converter. The evaluation and comparison between the radiographic systems have been performed at the Instituto de Engenharia Nuclear - CNEN, using the Argonauta Reactor as source of thermal neutrons and a commercially available imaging plate reader. (author)

Preliminary tests of a model of cooling-pond thermal performance

International Nuclear Information System (INIS)

Hicks, B.B.; Wesely, M.L.; Wilczek, J.

1975-01-01

Experiments performed during recent years at the cooling pond complex at the Dresden nuclear power station have been designed to improve our understanding of the fundamental properties of thermal exchange at a warm-water surface. To a considerable extent, the field studies have been successful in that they have shown that modern micrometeorological techniques can be successfully applied to the demanding circumstances of an industrial cooling lake at temperature of at least 40 0 C. The intent of these studies has been to create a set of parameterization schemes good enough to allow simulation of the performance of the Dresden cooling lake without adjustment of numerical constants. An obvious extension of these studies, and one of the goals of the cooling-pond research program as presently stated, is to obtain an accurate numerical simulation of thermal performance of ponds with use of the improved formulations that have resulted from the experimental work at the Dresden lake. The computer model is divided into two sections and can be used to test the sensitivity of predicted performance to variations in procedures for determining the thermal transfer from the surface

Supervision of the thermal performance of heat exchanger trains

Energy Technology Data Exchange (ETDEWEB)

Negrao, C.O.R.; Tonin, P.C.; Madi, M. [Federal University of Technology Parana UTFPR, Post-graduate Program in Mechanical and Materials Engineering PPGEM, Thermal Science Laboratory LACIT, Av. Sete de Setembro, 3165, CEP 80230-901, Curitiba, Parana (Brazil)

2007-02-15

In oil refining, heat exchanger networks are employed to recover heat and therefore save energy of the plant. However, many heat exchangers in crude oil pre-heat trains are under high risk of fouling. Under fouling conditions, the thermal performance of heat exchangers is continuously reduced and its supervision becomes an important task. The large number of heat exchangers in pre-heat trains and the change of operation conditions and feedstock charges make the daily supervision a difficult task. This work applies an approach to follow the performance of heat exchangers [M.A.S. Jeronimo, L.F. Melo, A.S. Braga, P.J.B.F. Ferreira, C. Martins, Monitoring the thermal efficiency of fouled heat exchangers - A simplified method, Experimental Thermal and Fluid Science 14 (1997) 455-463] and extends it to monitor the whole train. The approach is based on the comparison of measured and predicted heat exchanger effectiveness. The measured value is computed from the four inlet and outlet temperatures of a heat exchanger unit. The predicted clean and dirty values of effectiveness are calculated from classical literature relations as a function of NTU and of heat capacity ratio (R). NTU and R are continuously adjusted according to mass flow rate changes. An index of fouling is defined for the whole network and the results show the performance degradation of the network with time. The work also suggests that Jeronimo's index of fouling can be used to estimate the fouling thermal resistance of heat exchangers. (author)

Output performance analyses of solar array on stratospheric airship with thermal effect

International Nuclear Information System (INIS)

Li, Jun; Lv, Mingyun; Tan, Dongjie; Zhu, Weiyu; Sun, Kangwen; Zhang, Yuanyuan

2016-01-01

Highlights: • A model investigating the output power of solar array is proposed. • The output power in the cruise condition with thermal effect is researched. • The effect of some factors on output performance is discussed in detail. • A suitable transmissivity of external layer is crucial in preliminary design step. - Abstract: Output performance analyses of the solar array are very critical for solving the energy problem of a long endurance stratospheric airship, and the solar cell efficiency is very sensitive to temperature of the solar cell. But the research about output performance of solar array with thermal effect is rare. This paper outlines a numerical model including the thermal model of airship and solar cells, the incident solar radiation model on the solar array, and the power output model. Based on this numerical model, a MATLAB computer program is developed. In the course of the investigation, the comparisons of the simulation results with and without considering thermal effect are reported. Furthermore, effects of the transmissivity of external encapsulation layer of solar array and wind speed on the thermal performance and output power of solar array are discussed in detail. The results indicate that this method is helpful for planning energy management.

Long term energy performance analysis of Egbin thermal power ...

African Journals Online (AJOL)

This study is aimed at providing an energy performance analysis of Egbin thermal power plant. The plant operates on Regenerative Rankine cycle with steam as its working fluid .The model equations were formulated based on some performance parameters used in power plant analysis. The considered criteria were plant ...

Availability Performance Analysis of Thermal Power Plants

Science.gov (United States)

Bhangu, Navneet Singh; Singh, Rupinder; Pahuja, G. L.

2018-03-01

This case study presents the availability evaluation method of thermal power plants for conducting performance analysis in Indian environment. A generic availability model has been proposed for a maintained system (thermal plants) using reliability block diagrams and fault tree analysis. The availability indices have been evaluated under realistic working environment using inclusion exclusion principle. Four year failure database has been used to compute availability for different combinatory of plant capacity, that is, full working state, reduced capacity or failure state. Availability is found to be very less even at full rated capacity (440 MW) which is not acceptable especially in prevailing energy scenario. One of the probable reason for this may be the difference in the age/health of existing thermal power plants which requires special attention of each unit from case to case basis. The maintenance techniques being used are conventional (50 years old) and improper in context of the modern equipment, which further aggravate the problem of low availability. This study highlights procedure for finding critical plants/units/subsystems and helps in deciding preventive maintenance program.

Thermal Performance and Reliability Characterization of Bonded Interface Materials (BIMs): Preprint

Energy Technology Data Exchange (ETDEWEB)

DeVoto, D.; Paret, P.; Mihalic, M.; Narumanchi, S.; Bar-Cohen, A.; Matin, K.

2014-08-01

Thermal interface materials are an important enabler for low thermal resistance and reliable electronics packaging for a wide array of applications. There is a trend towards bonded interface materials (BIMs) because of their potential for low thermal resistivity (< 1 mm2K/W). However, BIMs induce thermomechanical stresses in the package and can be prone to failures and integrity risks. Deteriorated interfaces can result in high thermal resistance in the package and degradation and/or failure of the electronics. DARPA's Thermal Management Technologies program has addressed this challenge, supporting the development of mechanically-compliant, low resistivity nano-thermal interface (NTI) materials. In this work, we describe the testing procedure and report the results of NREL's thermal performance and reliability characterization of an initial sample of four different NTI-BIMs.

Assessment, mechanisms, prevention, and measures for quick recovery of military operation-associated fatigue

OpenAIRE

Zhao-shen LI; Wen HUANG

2012-01-01

Fatigue is a worldwide problem. Military members frequently feel fatigue in military operations, which hinders the successful completion of their tasks. In complicated international military environments, military fatigue has received great attention from the armed forces in all countries. The present paper elaborates the performances, assessment, and mechanism of fatigue in military operations. In addition, the current study discusses the prevention and rapid recovery of fatigue, aiming at p...

Thermal and Hygric Expansion of High Performance Concrete

Directory of Open Access Journals (Sweden)

J. Toman

2001-01-01

Full Text Available The linear thermal expansion coefficient of two types of high performance concrete was measured in the temperature range from 20 °C to 1000 °C, and the linear hygric expansion coefficient was determined in the moisture range from dry material to saturation water content. Comparative methods were applied for measurements of both coefficients. The experimental results show that both the effect of temperature on the values of linear thermal expansion coefficients and the effect of moisture on the values of linear hygric expansion coefficients are very significant and cannot be neglected in practical applications.

Preparation and thermal performance of paraffin/Nano-SiO2 nanocomposite for passive thermal protection of electronic devices

International Nuclear Information System (INIS)

Wang, Yaqin; Gao, Xuenong; Chen, Peng; Huang, Zhaowen; Xu, Tao; Fang, Yutang; Zhang, Zhengguo

2016-01-01

Highlights: • Three types of paraffin/nano-SiO 2 nanocomposites were prepared and characterized. • Thermo-physical properties of these composites were determined and compared. • One composite with lower thermal conductivity showed better thermal insulation properties. • This composite was identified as thermal insulation material for electronic components. - Abstract: In this paper, three grades of nano silicon dioxide (nano-SiO 2 ), NS1, NS2 and NS3, were mixed into paraffin to prepare nanocomposites as novel insulation materials for electronic passive thermal protection applications. The optimal mass percentages of paraffin for the three composites, NS1P, NS2P and NS3P, were determined to be 75%, 70% and 65%, respectively. Investigations by means of scanning electron micrographs (SEM), differential scanning calorimeter (DSC), thermogravimetric analysis (TG), hot disk analyzer and thermal protection performance tests were devoted to the morphology, thermal properties and thermal protection performance analysis of composites. Experimental results showed that paraffin uniformly distributed into the pores and on the surface of nano-SiO 2 . Melting points of composites declined and experimental latent heat became lower than the calculated values with the decrease of nano-SiO 2 pore size. The NS1P composite had larger thermal storage capacity, better reliability and stability compared with NS2P and NS3P. In addition, compared with 90% wt.% paraffin/EG composite, the incorporation of NS1 (25 wt.%) into paraffin caused not only 63.2% reduction in thermal conductivity, but also 21.8% increase in thermal protection time affected by the ambient temperature. Thus those good properties confirmed that NS1P (75 wt.%) composite was a viable candidate for protecting electronic devices under high temperature environment.

Prevention of flight-related neck pain in military aircrew

NARCIS (Netherlands)

van den Oord, M.H.A.H.

2012-01-01

Military pilots and rear aircrew members are occupations with several occupational exposures that might cause neck pain. In addition to the negative impact of neck pain on health, safety is one of the main concerns for the military aviation, because neck pain may interfere with flying performance.

Role of thermal resistance on the performance of superconducting radio frequency cavities

Science.gov (United States)

Dhakal, Pashupati; Ciovati, Gianluigi; Myneni, Ganapati Rao

2017-03-01

Thermal stability is an important parameter for the operation of the superconducting radio frequency (SRF) cavities used in particle accelerators. The rf power dissipated on the inner surface of the cavities is conducted to the helium bath cooling the outer cavity surface and the equilibrium temperature of the inner surface depends on the thermal resistance. In this manuscript, we present the results of direct measurements of thermal resistance on 1.3 GHz single cell SRF cavities made from high purity large-grain and fine-grain niobium as well as their rf performance for different treatments applied to outer cavity surface in order to investigate the role of the Kapitza resistance to the overall thermal resistance and to the SRF cavity performance. The results show no significant impact of the thermal resistance to the SRF cavity performance after chemical polishing, mechanical polishing or anodization of the outer cavity surface. Temperature maps taken during the rf test show nonuniform heating of the surface at medium rf fields. Calculations of Q0(Bp) curves using the thermal feedback model show good agreement with experimental data at 2 and 1.8 K when a pair-braking term is included in the calculation of the Bardeen-Cooper-Schrieffer surface resistance. These results indicate local intrinsic nonlinearities of the surface resistance, rather than purely thermal effects, to be the main cause for the observed field dependence of Q0(Bp) .

Role of thermal resistance on the performance of superconducting radio frequency cavities

Directory of Open Access Journals (Sweden)

Pashupati Dhakal

2017-03-01

Full Text Available Thermal stability is an important parameter for the operation of the superconducting radio frequency (SRF cavities used in particle accelerators. The rf power dissipated on the inner surface of the cavities is conducted to the helium bath cooling the outer cavity surface and the equilibrium temperature of the inner surface depends on the thermal resistance. In this manuscript, we present the results of direct measurements of thermal resistance on 1.3 GHz single cell SRF cavities made from high purity large-grain and fine-grain niobium as well as their rf performance for different treatments applied to outer cavity surface in order to investigate the role of the Kapitza resistance to the overall thermal resistance and to the SRF cavity performance. The results show no significant impact of the thermal resistance to the SRF cavity performance after chemical polishing, mechanical polishing or anodization of the outer cavity surface. Temperature maps taken during the rf test show nonuniform heating of the surface at medium rf fields. Calculations of Q_{0}(B_{p} curves using the thermal feedback model show good agreement with experimental data at 2 and 1.8 K when a pair-braking term is included in the calculation of the Bardeen-Cooper-Schrieffer surface resistance. These results indicate local intrinsic nonlinearities of the surface resistance, rather than purely thermal effects, to be the main cause for the observed field dependence of Q_{0}(B_{p}.

Volume Fraction Dependent Thermal Performance of UAlx-Al Dispersion Target

Energy Technology Data Exchange (ETDEWEB)

Kong, Eui Hyun; Tahk, Young Wook; Kim, Hyun Jung; Oh, Jae Yong; Yim, Jeong Sik [KAERI, Daejeon (Korea, Republic of)

2016-05-15

Unlike U-Al alloys, properties of UAl{sub x}-Al dispersion target can be highly sensitive to volume fraction of UAlx in a target meat due to the interface resistance between target particles and matrix. The interface resistance effects on properties of the target meat including thermal conductivity, thermal expansion coefficient, specific heat, elastic modulus and so on. Thermal performances of a dispersion target meat were theoretically evaluated under normal operation condition of KJRR (Kijang Research Reactor) during short effective full power days (EFPD) of 7 days, based on reported measured thermal conductivities of UAl{sub x}-Al dispersion fuels. Effective thermal conductivity determines maximum temperature of dispersion target plate. And for that volume fraction of UAlx in target meat has to be determined considering manufacturing of target plate without degradation of physical and mechanical characteristics.

Utility experience using THERMAC for plant thermal performance analysis

International Nuclear Information System (INIS)

Jain, P.K.; Doran, K.J.

1993-01-01

THERMAC is a state-of-the-art software package designed to assist those responsible for monitoring and evaluating the thermal performance of fossil and nuclear power plants. It is an integrated program, available on PCs and selected workstations, that combines strong analytical capabilities with a graphical user interface and object-oriented database. The software accurately analyses all of the components of a power plant from first principles. The graphical user interface is employed to build plant specific models; it can also be used to create custom screen displays. THERMAC is able to read plant measurements and statistically account for any missing or erroneous plant data; it does not require any additional plant instrumentation. THERMAC can be used to archive historical data, generate customized trending plots and periodic performance reports. open-quotes What-if close-quote studies can be conducted to predict the impact of corrective actions on thermal performance

Military and Political Studies

OpenAIRE

Alexey I. Podberyozkin

2014-01-01

Military-political issues is an important area of research work at MGIMO. The difference in this direction from the classical international specialization is that it is at the intersection of several disciplines: military science, military-technical and military-industrial as well as International Relations. A specialist in military and political issues should not only be an expert in the field of international relations and diplomacy, but also have a deep knowledge of military-technical issu...

Virtual Reality Applications for Stress Management Training in the Military.

Science.gov (United States)

Pallavicini, Federica; Argenton, Luca; Toniazzi, Nicola; Aceti, Luciana; Mantovani, Fabrizia

2016-12-01

Stress Management Training programs are increasingly being adopted in the military field for resilience empowerment and primary stress prevention. In the last several years, advanced technologies (virtual reality in particular) have been integrated in order to develop more innovative and effective stress training programs for military personnel, including soldiers, pilots, and other aircrew professionals. This systematic review describes experimental studies that have been conducted in recent years to test the effectiveness of virtual reality-based Stress Management Training programs developed for military personnel. This promising state-of-the-art technology has the potential to be a successful new approach in empowering soldiers and increasing their resilience to stress. To provide an overview from 2001 to 2016 of the application of virtual reality for Stress Management Training programs developed for the military, a computer-based search for relevant publications was performed in several databases. Databases used in the search were PsycINFO, Web of Science (Web of Knowledge), PubMed, and Medline. The search string was: ("Virtual Reality") AND ("Military") AND ["Stress Training" OR ("Stress Management")]. There were 14 studies that met the inclusion criteria and were included in the review. The main observation to be drawn from this review is that virtual reality can provide interactive Stress Management Training to decrease levels of perceived stress and negative affect in military personnel. This technology appears to be a promising tool for assessing individuals' resilience to stress and for identifying the impact that stress can have on physiological reactivity and performance.Pallavicini F, Argenton L, Toniazzi N, Aceti L, Mantovani F. Virtual realtiy applications for stress management training in the military. Aerosp Med Hum Perform. 2016; 87(12):1021-1030.

An examination of OLED display application to military equipment

Science.gov (United States)

Thomas, J.; Lorimer, S.

2010-04-01

OLED display technology has developed sufficiently to support small format commercial applications such as cell-phone main display functions. Revenues seem sufficient to finance both performance improvements and to develop new applications. The situation signifies the possibility that OLED technology is on the threshold of credibility for military applications. This paper will examine both performance and some possible applications for the military ground mobile environment, identifying the advantages and disadvantages of this promising new technology.

Fabrication and performance evaluation of flexible heat pipes for potential thermal control of foldable electronics

International Nuclear Information System (INIS)

Yang, Chao; Chang, Chao; Song, Chengyi; Shang, Wen; Wu, Jianbo; Tao, Peng; Deng, Tao

2016-01-01

Highlights: • A flexible and high-performance heat pipe is fabricated. • Bending effect on thermal performance of flexible heat pipes is evaluated. • Theoretical analysis is carried out to reveal the change of thermal resistance with bending. • Thermal control of foldable electronics with flexible heat pipes is demonstrated. - Abstract: In this work, we report the fabrication and thermal performance evaluation of flexible heat pipes prepared by using a fluororubber tube as the connector in the adiabatic section and using strong base treated hydrophilic copper meshes as the wick structure. Deionized water was chosen as working fluid and three different filling ratios (10%, 20%, and 30%) of working fluid were loaded into the heat pipe to investigate its impact on thermal performance. The fabricated heat pipes can be easily bended from 0"o to 180"o in the horizontal operation mode and demonstrated consistently low thermal resistances after repeated bending. It was found that with optimized amount of working fluid, the thermal resistance of flexible heat pipes increased with larger bending angles. Theoretical analysis reveals that bending disturbs the normal vapor flow from evaporator to condenser in the heat pipe, thus leads to increased liquid–vapor interfacial thermal resistance in the evaporator section. The flexible heat pipes have been successfully applied for thermal control of foldable electronic devices showing superior uniform heat-transfer performance.

Tobacco Pricing in Military Stores: Views of Military Policy Leaders.

Science.gov (United States)

Smith, Elizabeth A; Jahnke, Sara A; Poston, Walker S C; Malone, Ruth E; Haddock, Christopher K

2016-10-01

Higher tobacco taxes reduce tobacco use. On military installations, cigarettes and other tobacco products are sold tax-free, keeping prices artificially low. Pricing regulations in the military specify that tobacco should be within 5% of the local most competitive price, but prices still average almost 13% lower than those at local Walmarts. To gain insight into policy leaders' ideas and positions on military tobacco pricing, we interviewed members of the Department of Defense (DoD) Addictive Substances Misuse Advisory Committee and the Advisory Committee on Tobacco about tobacco pricing policies (n = 12). Participants frequently lacked specific knowledge of details of military pricing policy, and the impact higher prices might have on military tobacco use. Most participants thought tobacco should not be sold at military stores, but many also felt that this policy change was unlikely due to tobacco industry pressure, and DoD reliance on tobacco profits to support Morale, Welfare, and Recreation funds. Achieving a tobacco-free military will require changing pricing policy, but this study suggests that for effective implementation, military leadership must also understand and articulate more clearly the rationale for doing so. Previous work has found that adherence to military tobacco pricing policy is inconsistent at best. This study suggests that lack of knowledge about the policy and conflicting pressures resulting from the funding stream tobacco sales represent extend to high level military policy leaders. Without clearer information and direction, these leaders are unlikely to be able to establish and implement better tobacco pricing policy. © The Author 2016. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Thermal performance measurement and application of a multilayer insulator for emergency architecture

International Nuclear Information System (INIS)

Salvalai, Graziano; Imperadori, Marco; Scaccabarozzi, Diego; Pusceddu, Cristina

2015-01-01

Lightness coupled with a quick assembly method is crucial for emergency architecture in post-disaster area where accessibility and action time play a huge barer to rescue people. In this prospective, the following work analyses the potentiality (technological and thermal performances) of multilayer insulator for a new shelter envelope able to provide superior thermal comfort for the users. The thermal characteristics are derived experimentally by means of a guard ring apparatus under different working temperatures. Tests are performed on the multilayer insulator itself and on a composite structure, made of the multilayer insulator and two air gaps wrapped by a polyester cover, which is the core of a new lightweight emergency architecture. Experimental results show good agreement with literature data, providing a thermal conductivity and transmittance of about 0.04 W/(m °C) and 1.6 W/(m 2  °C) for the tested multilayer. The composite structure called Thermo Reflective Multilayer System (TRMS) shows better insulation performances, providing a thermal transmittance set to 0.85 W/(m 2  °C). A thermal model of an emergency tent based on the new insulating structure (TRMS) has been developed and its thermal performances have been compared with those of a UNHCR traditional emergency shelter. The shelter model was simulated (Trnsys v.17 environment) in the winter season considering the climate of Belgrade and using only the casual gains from occupant and solar radiation through opaque wall. Numerical simulations evidenced that the new insulating composite envelope reduces required heating load of about two and four times with respect to the traditional insulation. The study sets a starting point to develop a lightweight emergency architecture made with a combination between multilayer, air, polyester and vulcanized rubber. - Highlights: • Multilayer insulator tested by means of a guard ring apparatus. • Thermo reflective multilayer system (TRMS) development

Military Librarians Workshop: A Premier Gathering of Military Librarians, 1957-1999

National Research Council Canada - National Science Library

Palmer, William A., Jr; Hanna, Marcia

2000-01-01

The Military Librarian Workshop(MLW) is an annual meeting that brings together civilian and military personnel who serve as special librarians, library supervisors, or technical information officers in military or governmental...

Is Long Term Creatine and Glutamine Supplementation Effective in Enhancing Physical Performance of Military Police Officers?

Directory of Open Access Journals (Sweden)

Lázaro da Silveira Celismar

2014-12-01

Full Text Available The objective of this study was to analyze the effect of supplementation with creatine and glutamine on physical fitness of military police officers. Therefore, an experimental double blind study was developed, with the final sample composed by 32 men randomly distributed into three groups: a group supplemented with creatine (n=10, glutamine (n=10 and a placebo group (n=12 and evaluated in three distinct moments, in an interval of three months (T1, T2 and T3. The physical training had a weekly frequency of 5 sessions x 90 min, including strength exercises, local muscular resistance, flexibility and both aerobic and anaerobic capacity. After analyzing the effect of time, group and interaction (group x time for measures that indicated the physical capabilities of the subjects, a significant effect of time for the entire variable was identified (p0,05. In face of the results it was concluded that supplementation with creatine and glutamine showed no ergogenic effect on physical performance in military police officers.

Committee on Military Nutrition Research

National Research Council Canada - National Science Library

Poos, Mary

2000-01-01

.... Its purpose is to provide reviews and recommendations to the Commander, U.S. Army Medical Research and Materiel Command, on research projects, programs, and products as they relate to the nutrition and performance of military personnel...

ACCESS: Thermal Mechanical Design, Performance, and Status

Science.gov (United States)

Kaiser, Mary Elizabeth; Morris, M. J.; McCandliss, S. R.; Rauscher, B. J.; Kimble, R. A.; Kruk, J. W.; Wright, E. L.; Bohlin, R.; Kurucz, R. L.; Riess, A. G.; Pelton, R.; Deustua, S. E.; Dixon, W. V.; Sahnow, D. J.; Benford, D. J.; Gardner, J. P.; Feldman, P. D.; Moos, H. W.; Lampton, M.; Perlmutter, S.; Woodgate, B. E.

2014-01-01

Systematic errors associated with astrophysical data used to probe fundamental astrophysical questions, such as SNeIa observations used to constrain dark energy theories, are now rivaling and exceeding the statistical errors associated with these measurements. ACCESS: Absolute Color Calibration Experiment for Standard Stars is a series of rocket-borne sub-orbital missions and ground-based experiments designed to enable improvements in the precision of the astrophysical flux scale through the transfer of absolute laboratory detector standards from the National Institute of Standards and Technology (NIST) to a network of stellar standards with a calibration accuracy of 1% and a spectral resolving power of 500 across the 0.35 - 1.7μm bandpass. Achieving this level of accuracy requires characterization and stability of the instrument and detector including a thermal background that contributes less than 1% to the flux per resolution element in the NIR. We will present the instrument and calibration status with a focus on the thermal mechanical design and associated performance data. The detector control and performance will be presented in a companion poster (Morris, et al). NASA APRA sounding rocket grant NNX08AI65G supports this work.

To the Question on the Nature of Military Threats and Non-Military Responses

Directory of Open Access Journals (Sweden)

Sambu R. Tsyrendorzhjyev

2015-01-01

Full Text Available The notion of "military danger, military threats, military and non-military measures to Parry, and other definitions from the policy of the State to ensure the military security of the now widely used in journalism, conceptual, other documents and research. The attentive reader it is not difficult to notice the ambiguity in the interpretation of these concepts. This makes it difficult to not only the perception of the relevant topics for ensuring military security publications, but also the development of the theory and practice of ensuring the defence and security of the State. The author's view on the essence of the reasoning logic of non-military measures to counter military threats, as the ultimate goal of the article is the following.First the task of analyzing the concept of "national security", "object of national security" and understand the functions of the State, society and the individual to ensure national security. Decomposition of an object of national security, which is "national property" (the content of the concepts described in the article has made it possible to substantiate the basis for classification of national security threats and with better understanding of the nature, variety, Genesis. This provided a rationale for the role and the place of the tasks ensuring military security in the common task of ensuring national security, the correlation of military and non-military threats.The final phase of the research, the results of which are set out in the article is devoted to analysis of military threats, which made it possible to identify their main structural elements: source, media, military-political and strategic nature, install the main factors defining the content of these elements and their interaction. Based on these results, the proposed definition of the essence of non-military measures for counteracting of military threats, as well as guidelines for developing these measures.

Feasibility and Performance of the Microwave Thermal Rocket Launcher

Science.gov (United States)

Parkin, Kevin L. G.; Culick, Fred E. C.

2004-03-01

Beamed-energy launch concepts employing a microwave thermal thruster are feasible in principle, and microwave sources of sufficient power to launch tons into LEO already exist. Microwave thermal thrusters operate on an analogous principle to nuclear thermal thrusters, which have experimentally demonstrated specific impulses exceeding 850 seconds. Assuming such performance, simple application of the rocket equation suggests that payload fractions of 10% are possible for a single stage to orbit (SSTO) microwave thermal rocket. We present an SSTO concept employing a scaled X-33 aeroshell. The flat aeroshell underside is covered by a thin-layer microwave absorbent heat-exchanger that forms part of the thruster. During ascent, the heat-exchanger faces the microwave beam. A simple ascent trajectory analysis incorporating X-33 aerodynamic data predicts a 10% payload fraction for a 1 ton craft of this type. In contrast, the Saturn V had 3 non-reusable stages and achieved a payload fraction of 4%.

Military Nutrition Research: Four Tasks to Address Personnel Readiness and Warfighter Performance

National Research Council Canada - National Science Library

Ryan, Donna

2007-01-01

... and Materiel Command (USAMRMC) and PBRC, PBRC provides high quality analytical laboratory, nutrition database and metabolic unit support for military nutrition clinical research protocols. Specific Aims...

Military service and military vocational training effects on post-service earnings

OpenAIRE

Bolin, Phil Warren

1980-01-01

Approved for public release; distribution is unlimited. The influence of military service and military vocational training on post-service earnings was analyzed using the National Longitudinal Survey of young men (14-24 years of age in 1966) . When individuals were classified by their propensity to use training neither military service nor military vocational training was a significant determinant of post-service earnings. A disaggregation of the sample IQ revealed that m...

Evaluation of Strategies to Improve the Thermal Performance of Steel Frames in Curtain Wall Systems

Directory of Open Access Journals (Sweden)

Ji Hyun Oh

2016-12-01

Full Text Available Recently, metal curtain wall systems have been widely used in high-rise buildings due to many advantages, including being lightweight, rapid construction, and aesthetic features. Since the metal frame may lead to lower energy performance, thermal discomfort, and condensation risk due to the high thermal conductivity, its thermal performance can be important for the improvement of the overall thermal performance of the curtain wall system, as well as the energy efficiency of the building envelope. This study aims to evaluate variety of design strategies to improve the thermal performance of steel curtain wall frames. Five base cases and three further steps were selected for two different head profile shapes based on a state-of-the art technology review, and their thermal transmittances were calculated through simulations according to the ISO 12631 standard which is an international standard for calculating thermal transmittance of curtain wall system. Measured results that were obtained from hot-box tests were compared with the calculated results to validate the simulation method of this study. The shape of the head profile did not strongly influence the overall thermal transmittance, and the choice of strategies for the rabbet space was more important. More effective strategies could be decided according to the steps for variation development. This result can serve as a guideline for the design of high-performance curtain wall frames.

Ways to improve physical and thermal performance of refractory lining materials

Directory of Open Access Journals (Sweden)

Khlystov A.I.

2017-01-01

Full Text Available Refractory lining materials, which include ceramic refractories and nonfired heat-resistant concretes, have a very short lifespan during the turnaround time measured in years and sometimes months. Therefore, increasing the service life of thermal generating units by 1.5-2 times will bring significant economic benefits. The main factor that determines the durability of refractory lining materials is the thermal resistance. It is possible to increase the thermal resistance by improving such physical and mechanical properties as strength and density. As for the ceramic refractory performance improvement, such technological methods as their structural and chemical modification by phosphate binder impregnation, as well as introduction of phosphate components into the ceramic batches during the molding process increase, in particular, their thermal stability. The use of aluminous and high-alumina cements contributes to a significant increase of not only strength, but also physical and thermal performance of heat-resistant concretes with different fillers. Switching to the use of chemical binders in the compositions of heat-resistant concretes (liquid glass with effective hardeners; silicate-block and phosphate binders enables to develop high-heat resistant materials which do not soften in a wide range of heating temperatures from 400 °С to 1600 °С. The positive results on increasing the thermal resistance of heat-resistant composites can be obtained by reinforcing them with high temperature fibers.

Thermal ecological physiology of native and invasive frog species: do invaders perform better?

Science.gov (United States)

Cortes, Pablo A; Puschel, Hans; Acuña, Paz; Bartheld, José L; Bozinovic, Francisco

2016-01-01

Biological invasions are recognized as an important biotic component of global change that threatens the composition, structure and functioning of ecosystems, resulting in loss of biodiversity and displacement of native species. Although ecological characteristics facilitating the establishment and spread of non-native species are widely recognized, little is known about organismal attributes underlying invasion success. In this study, we tested the effect of thermal acclimation on thermal tolerance and locomotor performance in the invasive Xenopus laevis and the Chilean native Calyptocephalella gayi . In particular, the maximal righting performance (μ MAX ), optimal temperature ( T O ), lower (CT min ) and upper critical thermal limits (CT max ), thermal breadth ( T br ) and the area under the performance curve (AUC) were studied after 6 weeks acclimation to 10 and 20°C. We observed higher values of μ max and AUC in X. laevis in comparison to C. gayi . On the contrary, the invasive species showed lower values of CT min in comparison to the native one. In contrast, CT max , T O and T br showed no inter-specific differences. Moreover, we found that both species have the ability to acclimate their locomotor performance and lower thermal tolerance limit at low temperatures. Our results demonstrate that X. laevis is a better performer than C. gayi . Although there were differences in CT min , the invasive and native frogs did not differ in their thermal tolerance. Interestingly, in both species the lower and upper critical thermal limits are beyond the minimal and maximal temperatures encountered in nature during the coldest and hottest month, respectively. Overall, our findings suggest that both X. laevis and C. gayi would be resilient to climate warming expectations in Chile.

Thermal performance of various multilayer insulation systems below 80K

International Nuclear Information System (INIS)

Boroski, W.N.; Nicol, T.H.; Schoo, C.J.

1992-04-01

The SSC collider dipole cryostat consists of a vacuum shell operating at room temperature, two thermal shields operating near 80K and 20K respectively, and the superconducting magnet assembly operating near 4K. The cryostat design incorporates multilayer insulation (MLI) blankets to limit radiant heat transfer into the 80K and 20K thermal shields. Also, an MLI blanket is used to impede heat transfer through residual gas conduction into the 4K superconducting magnet assembly. A measurement facility at Fermilab has been used to experimentally optimize the thermal insulation system for the dipole cryostat. Previous thermal measurements have been used to define the 80K MLI system configuration and verify system performance. With the 80K MLI system defined, the current effort has focused on experimentally defining the optimum insulation scheme for the 20K thermal shield. The SSC design specification requires that radiant heat transfer be limited to 0.093 W/m 2 at an insulating vacuum of 10 -6 torr

The performance analysis of the Trough Concentrating Solar Photovoltaic/Thermal system

Energy Technology Data Exchange (ETDEWEB)

Li, M., E-mail: liming@ynnu.edu.c [Solar Energy Research Institute, Yunnan Normal University, 650092 Kunming (China); Li, G.L. [School of Physics and Electronic Information, Yunnan Normal University, Kunming 650092 (China); Ji, X.; Yin, F.; Xu, L. [Solar Energy Research Institute, Yunnan Normal University, 650092 Kunming (China)

2011-06-15

Research highlights: {yields} A 2 m{sup 2} Trough Concentrating Photovoltaic/Thermal (TCPV/T) system is built, a single crystalline silicon solar cell array, a polycrystalline silicon cell array, a Super cell array and a GaAs cell array are respectively used in the experiments. {yields} Another 10 m{sup 2} TCPV/T system using the GaAs cell array and a concentrating silicon cell array are also constructed and characterized. {yields} The economic performance analysis show the electricity generating cost of the TCPV/T system with the concentrating silicon cell array can catch up with flat-plate PV system. -- Abstract: The electrical and thermal performance of a 2 m{sup 2} Trough Concentrating Photovoltaic/Thermal (TCPV/T) system with an energy flux ratio 10.27 are characterized by experiments. A single crystalline silicon solar cell array, a polycrystalline silicon cell array, a Super cell array and a GaAs cell array are respectively used in the experiments. The experimental results show that the electrical performance of the system with the GaAs cell array is better than that of crystal silicon solar cell arrays. The superior output performance of the GaAs cell array mainly benefits from its lower series resistance. But the thermal performances of the system using the single crystal silicon solar cell array and the polycrystalline silicon solar cell array are better. It results from the widths of the two types of cells in the system close to that of the focal line. Another 10 m{sup 2} TCPV/T system with an energy flux ratio of 20 using the GaAs cell array and a concentrating silicon cell array are also constructed and characterized. The experimental results indicate that the photoelectric efficiency of the GaAs cell array is 23.83%, and the instantaneous electrical efficiency and thermal efficiency of the system are 9.88% and 49.84% respectively. While the instantaneous electrical efficiency and thermal efficiency of the system using the low-cost concentrating

The performance analysis of the Trough Concentrating Solar Photovoltaic/Thermal system

International Nuclear Information System (INIS)

Li, M.; Li, G.L.; Ji, X.; Yin, F.; Xu, L.

2011-01-01

Research highlights: → A 2 m 2 Trough Concentrating Photovoltaic/Thermal (TCPV/T) system is built, a single crystalline silicon solar cell array, a polycrystalline silicon cell array, a Super cell array and a GaAs cell array are respectively used in the experiments. → Another 10 m 2 TCPV/T system using the GaAs cell array and a concentrating silicon cell array are also constructed and characterized. → The economic performance analysis show the electricity generating cost of the TCPV/T system with the concentrating silicon cell array can catch up with flat-plate PV system. -- Abstract: The electrical and thermal performance of a 2 m 2 Trough Concentrating Photovoltaic/Thermal (TCPV/T) system with an energy flux ratio 10.27 are characterized by experiments. A single crystalline silicon solar cell array, a polycrystalline silicon cell array, a Super cell array and a GaAs cell array are respectively used in the experiments. The experimental results show that the electrical performance of the system with the GaAs cell array is better than that of crystal silicon solar cell arrays. The superior output performance of the GaAs cell array mainly benefits from its lower series resistance. But the thermal performances of the system using the single crystal silicon solar cell array and the polycrystalline silicon solar cell array are better. It results from the widths of the two types of cells in the system close to that of the focal line. Another 10 m 2 TCPV/T system with an energy flux ratio of 20 using the GaAs cell array and a concentrating silicon cell array are also constructed and characterized. The experimental results indicate that the photoelectric efficiency of the GaAs cell array is 23.83%, and the instantaneous electrical efficiency and thermal efficiency of the system are 9.88% and 49.84% respectively. While the instantaneous electrical efficiency and thermal efficiency of the system using the low-cost concentrating silicon cell array are 7.51% and 42

The Effect of Internal Leakages on Thermal Performance in NPPs

International Nuclear Information System (INIS)

Heo, Gyun Young; Kim, Doo Won; Jang, Seok Bo

2007-01-01

Since the Balance Of Plant (BOP, limited to a turbine cycle in this study) does not contain radioactive material, regulatory authorities did not need to have concerns on it. As the interests on safety and performance is getting more serious and extensive, controlling the level of safety and performance of a BOP have just begun or is about to begin. The performance standards or ageing management programs of the major equipment in a BOP is being developed. The regulatory requirements for tests and/or maintenance are being actively built up. There is also a probabilistic approach quantifying performance of a BOP. The study on quantifying the rate of unanticipated shutdowns caused by careless maintenance and/or tests conducted in a BOP is going on. In this study, the modeling of the entire BOP and the methodologies of thermal performance analysis should be one of the must-have items as well. This study was achieved to ensure fundamental skills related to 1) the detailed steady-state modeling of a BOP and 2) thermal performance analysis under various conditions. Particularly, the paper will focus on the effect of internal leakages inside the valves and FeedWater Heaters (FWHs). The internal leakage is regarded as the flow movement through the isolated path but remaining inside the system boundary of a BOP. For instance, the leakage from one side of a valve seat to the other side, or the leakage through the cracked tubes or tube-sheets in a heat exchanger correspond to internal leakages. We made a BOP model of OPR1000 and investigated thermal performance under the internal leakage in Turbine Bypass Condenser Dump Valves (TBCDV) and FWHs

Shuttle TPS thermal performance and analysis methodology

Science.gov (United States)

Neuenschwander, W. E.; Mcbride, D. U.; Armour, G. A.

1983-01-01

Thermal performance of the thermal protection system was approximately as predicted. The only extensive anomalies were filler bar scorching and over-predictions in the high Delta p gap heating regions of the orbiter. A technique to predict filler bar scorching has been developed that can aid in defining a solution. Improvement in high Delta p gap heating methodology is still under study. Minor anomalies were also examined for improvements in modeling techniques and prediction capabilities. These include improved definition of low Delta p gap heating, an analytical model for inner mode line convection heat transfer, better modeling of structure, and inclusion of sneak heating. The limited number of problems related to penetration items that presented themselves during orbital flight tests were resolved expeditiously, and designs were changed and proved successful within the time frame of that program.

COMMIX analysis of four constant flow thermal upramp experiments performed in a thermal hydraulic model of an advanced LMR

International Nuclear Information System (INIS)

Yarlagadda, B.S.

1989-04-01

The three-dimensional thermal hydraulics computer code COMMIX-1AR was used to analyze four constant flow thermal upramp experiments performed in the thermal hydraulic model of an advanced LMR. An objective of these analyses was the validation of COMMIX-1AR for buoyancy affected flows. The COMMIX calculated temperature histories of some thermocouples in the model were compared with the corresponding measured data. The conclusions of this work are presented. 3 refs., 5 figs

Performance of silvered Teflon (trademark) thermal control blankets on spacecraft

Science.gov (United States)

Pippin, Gary; Stuckey, Wayne; Hemminger, Carol

1993-01-01

Silverized Teflon (Ag/FEP) is a widely used passive thermal control material for space applications. The material has a very low alpha/e ratio (less than 0.1) for low operating temperatures and is fabricated with various FEP thicknesses (as the Teflon thickness increases, the emittance increases). It is low outgassing and, because of its flexibility, can be applied around complex, curved shapes. Ag/FEP has achieved multiyear lifetimes under a variety of exposure conditions. This has been demonstrated by the Long Duration Exposure Facility (LDEF), Solar Max, Spacecraft Charging at High Altitudes (SCATHA), and other flight experiments. Ag/FEP material has been held in place on spacecraft by a variety of methods: mechanical clamping, direct adhesive bonding of tapes and sheets, and by Velcro(TM) tape adhesively bonded to back surfaces. On LDEF, for example, 5-mil blankets held by Velcro(TM) and clamping were used for thermal control over 3- by 4-ft areas on each of 17 trays. Adhesively bonded 2- and 5-mil sheets were used on other LDEF experiments, both for thermal control and as tape to hold other thermal control blankets in place. Performance data over extended time periods are available from a number of flights. The observed effects on optical properties, mechanical properties, and surface chemistry will be summarized in this paper. This leads to a discussion of performance life estimates and other design lessons for Ag/FEP thermal control material.

Numerical analysis on thermal performance of roof contained PCM of a single residential building

International Nuclear Information System (INIS)

Li, Dong; Zheng, Yumeng; Liu, Changyu; Wu, Guozhong

2015-01-01

Highlights: • Thermal performance of different roofs in cold area of China are investigated. • Effects of five different conditions on thermal performance of roofs are analyzed. • Delay time of temperatures peak in PCM roofs are beyond 3 h than common roof. - Abstract: The phase change material (PCM) applied in the roof can decrease the building energy consumption and improve the thermal comfort by enhancing the thermal energy storage capacity of building envelope. In the present work, the thermal performance of different kinds of roofs with and without PCM in Northeast and cold area of China, i.e. common roof and PCM roofs, have been investigated numerically. This study also explored the influencing factors of thermal behavior of the roofs, such as solar radiation intensity, transition temperature and latent heat of PCM, roof slope, PCM layer thickness, and absorption coefficients of external roof surface. The results show that the PCM roofs effect on the temperature delay in the room is very strong and the delay time of temperatures peak of base layer in PCM roofs are beyond 3 h than common roof. The effect of transition temperature and latent heat of PCM on the thermal performance of roofs is relatively weak, compared with the roof slope, PCM layer thickness and absorption coefficients of external roof surface

Density dependence of reactor performance with thermal confinement scalings

International Nuclear Information System (INIS)

Stotler, D.P.

1992-03-01

Energy confinement scalings for the thermal component of the plasma published thus far have a different dependence on plasma density and input power than do scalings for the total plasma energy. With such thermal scalings, reactor performance (measured by Q, the ratio of the fusion power to the sum of the ohmic and auxiliary input powers) worsens with increasing density. This dependence is the opposite of that found using scalings based on the total plasma energy, indicating that reactor operation concepts may need to be altered if this density dependence is confirmed in future research

The Effects of Exhaustive Military Activities in Man. The Performance of Small Isolated Military Units in Extreme Environmental Conditions

Science.gov (United States)

2001-03-01

parties (military, sportive or scientific) has endured unreasonable hardships if not complete failure due to foreseeable but not met requirements. Food is...been many new clothing materials. This development has been spurrd by the affluent market within the civilian (sporting activities) sector. Much of this

Further Development of the Assessment of Military Multitasking Performance: Iterative Reliability Testing.

Directory of Open Access Journals (Sweden)

Margaret M Weightman

Full Text Available The Assessment of Military Multitasking Performance (AMMP is a battery of functional dual-tasks and multitasks based on military activities that target known sensorimotor, cognitive, and exertional vulnerabilities after concussion/mild traumatic brain injury (mTBI. The AMMP was developed to help address known limitations in post concussive return to duty assessment and decision making. Once validated, the AMMP is intended for use in combination with other metrics to inform duty-readiness decisions in Active Duty Service Members following concussion. This study used an iterative process of repeated interrater reliability testing and feasibility feedback to drive modifications to the 9 tasks of the original AMMP which resulted in a final version of 6 tasks with metrics that demonstrated clinically acceptable ICCs of > 0.92 (range of 0.92-1.0 for the 3 dual tasks and > 0.87 (range 0.87-1.0 for the metrics of the 3 multitasks. Three metrics involved in recording subject errors across 2 tasks did not achieve ICCs above 0.85 set apriori for multitasks (0.64 and above 0.90 set for dual-tasks (0.77 and 0.86 and were not used for further analysis. This iterative process involved 3 phases of testing with between 13 and 26 subjects, ages 18-42 years, tested in each phase from a combined cohort of healthy controls and Service Members with mTBI. Study findings support continued validation of this assessment tool to provide rehabilitation clinicians further return to duty assessment methods robust to ceiling effects with strong face validity to injured Warriors and their leaders.

Thermal performance of a radiatively cooled system for quantum optomechanical experiments in space

International Nuclear Information System (INIS)

Pilan Zanoni, André; Burkhardt, Johannes; Johann, Ulrich; Aspelmeyer, Markus; Kaltenbaek, Rainer; Hechenblaikner, Gerald

2016-01-01

Highlights: • We improved performance and design aspects of a radiatively cooled instrument. • A heat-flow analysis showed near optimal performance of the shield design. • A simple modification to imaging optics allowed further improvements. • We studied the thermal behavior for different orbital cases. • A transfer-function analysis showed strong attenuation of thermal variations. - Abstract: Passive cooling of scientific instruments via thermal radiation to deep space offers many advantages over active cooling in terms of mission cost, lifetime and the achievable quality of vacuum and microgravity. Motivated by the mission proposal MAQRO to test the foundations of quantum physics harnessing a deep-space environment, we investigate the performance of a radiatively cooled instrument, where the environment of a test particle in a quantum superposition has to be cooled to less than 20 K. We perform a heat-transfer analysis between the instrument components and a transfer-function analysis on thermal oscillations induced by the spacecraft interior and dissipative sources. The thermal behavior of the instrument is discussed for an orbit around a Lagrangian point and for a highly elliptical Earth orbit. Finally, we investigate possible design improvements. These include a mirror-based design of the imaging system on the optical bench (OB) and an extension of the heat shields.

Conceptual model of male military sexual trauma.

Science.gov (United States)

Elder, William B; Domino, Jessica L; Rentz, Timothy O; Mata-Galán, Emma L

2017-08-01

Male sexual trauma is understudied, leaving much to be known about the unique mental health needs of male survivors. This study examined veteran men's perceptions of the effects of military sexual trauma. Military sexual trauma was defined as physically forced, verbally coerced, or substance-incapacitated acts experienced during military service. Interviews were conducted with 21 male veterans who reported experiencing military sexual trauma. Data were drawn together using a grounded theory methodology. Three categories emerged from data analysis, including (a) types of military sexual trauma (being touched in a sexual way against their will [N = 18]; sexual remarks directed at them [N = 15]; being physically forced to have sex [N = 13]); (b) negative life effects (difficulty trusting others [N = 18]; fear of abandonment [N = 17]; substance use [N = 13]; fear of interpersonal violence [N = 12]; conduct and vocational problems [N = 11]; irritability/aggression [N = 8]; insecurity about sexual performance [N = 8]; difficulty managing anger [N = 8]); and (c) posttraumatic growth (N = 15). Results from this study suggest sexual trauma in the military context may affect systems of self-organization, specifically problems in affective, self-concept, and relational domains, similar to symptoms of those who have experienced prolonged traumatic stressors. This model can be used by clinicians to select treatments that specifically target these symptoms and promote posttraumatic growth. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Three-Dimensional Numerical Evaluation of Thermal Performance of Uninsulated Wall Assemblies: Preprint

Energy Technology Data Exchange (ETDEWEB)

Ridouane, E. H.; Bianchi, M.

2011-11-01

This study describes a detailed three-dimensional computational fluid dynamics modeling to evaluate the thermal performance of uninsulated wall assemblies accounting for conduction through framing, convection, and radiation. The model allows for material properties variations with temperature. Parameters that were varied in the study include ambient outdoor temperature and cavity surface emissivity. Understanding the thermal performance of uninsulated wall cavities is essential for accurate prediction of energy use in residential buildings. The results can serve as input for building energy simulation tools for modeling the temperature dependent energy performance of homes with uninsulated walls.

High-performance ferroelectric and magnetoresistive materials for next-generation thermal detector arrays

Science.gov (United States)

Todd, Michael A.; Donohue, Paul P.; Watton, Rex; Williams, Dennis J.; Anthony, Carl J.; Blamire, Mark G.

2002-12-01

This paper discusses the potential thermal imaging performance achievable from thermal detector arrays and concludes that the current generation of thin-film ferroelectric and resistance bolometer based detector arrays are limited by the detector materials used. It is proposed that the next generation of large uncooled focal plane arrays will need to look towards higher performance detector materials - particularly if they aim to approach the fundamental performance limits and compete with cooled photon detector arrays. Two examples of bolometer thin-film materials are described that achieve high performance from operating around phase transitions. The material Lead Scandium Tantalate (PST) has a paraelectric-to-ferroelectric phase transition around room temperature and is used with an applied field in the dielectric bolometer mode for thermal imaging. PST films grown by sputtering and liquid-source CVD have shown merit figures for thermal imaging a factor of 2 to 3 times higher than PZT-based pyroelectric thin films. The material Lanthanum Calcium Manganite (LCMO) has a paramagnetic to ferromagnetic phase transition around -20oC. This paper describes recent measurements of TCR and 1/f noise in pulsed laser-deposited LCMO films on Neodymium Gallate substrates. These results show that LCMO not only has high TCR's - up to 30%/K - but also low 1/f excess noise, with bolometer merit figures at least an order of magnitude higher than Vanadium Oxide, making it ideal for the next generation of microbolometer arrays. These high performance properties come at the expense of processing complexities and novel device designs will need to be introduced to realize the potential of these materials in the next generation of thermal detectors.

High-Performance Molybdenum Coating by Wire–HVOF Thermal Spray Process

Science.gov (United States)

Tailor, Satish; Modi, Ankur; Modi, S. C.

2018-04-01

Coating deposition on many industrial components with good microstructural, mechanical properties, and better wear resistance is always a challenge for the thermal spray community. A number of thermal spray methods are used to develop such promising coatings for many industrial applications, viz. arc spray, flame spray, plasma, and HVOF. All these processes have their own limitations to achieve porous free, very dense, high-performance wear-resistant coatings. In this work, an attempt has been made to overcome this limitation. Molybdenum coatings were deposited on low-carbon steel substrates using wire-high-velocity oxy-fuel (W-HVOF; WH) thermal spray system (trade name HIJET 9610®). For a comparison, Mo coatings were also fabricated by arc spray, flame spray, plasma spray, and powder-HVOF processes. As-sprayed coatings were analyzed using x-ray diffraction, scanning electron microscopy for phase, and microstructural analysis, respectively. Coating microhardness, surface roughness, and porosity were also measured. Adhesion strength and wear tests were conducted to determine the mechanical and wear properties of the as-sprayed coatings. Results show that the coatings deposited by W-HVOF have better performance in terms of microstructural, mechanical, and wear resistance properties, in comparison with available thermal spray process (flame spray and plasma spray).

A global fouling factor methodology for analyzing steam generator thermal performance degradation

International Nuclear Information System (INIS)

Kreider, M.A.; White, G.A.; Varrin, R.D. Jr.

1998-06-01

Over the past few years, steam generator (SG) thermal performance degradation has led to decreased plant efficiency and power output at numerous PWR nuclear power plants with recirculating-type SGs. The authors have developed and implemented methodologies for quantitatively evaluating the various sources of SG performance degradation, both internal and external to the SG pressure boundary. These methodologies include computation of the global fouling factor history, evaluation of secondary deposit thermal resistance using deposit characterization data, and consideration of pressure loss causes unrelated to the tube bundle, such as hot-leg temperature streaming and SG moisture separator fouling. In order to evaluate the utility of the global fouling factor methodology, the authors performed case studies for a number of PWR SG designs. Key results from two of these studies are presented here. In tandem with the fouling-factor analyses, a study evaluated for each plant the potential causes of pressure loss. The combined results of the global fouling factor calculations and the pressure-loss evaluations demonstrated two key points: (1) that the available thermal margin against fouling, which can vary substantially from plant to plant, has an important bearing on whether a given plant exhibits losses in electrical generating capacity, and (2) that a wide variety of causes can result in SG thermal performance degradation

Sixty years of the Military Technical Courier: Origins of the military technical thinking in the military printing of the Kingdom of Serbia

Directory of Open Access Journals (Sweden)

Ivan B. Mijatović

2012-04-01

Full Text Available The article sheds light on the origins of the military technical thinking in the military publishing of the Kingdom of Serbia with a view to marking a jubilee - the sixtieth anniversary of the Military Technical Courier. 'Vojin', the first military review, printed in the middle of 19th century as a private venture, covered a wide scope of military issues, among which a special place was given to 'the science of weapons'. No sooner had this review ceased to exist than The Headquarters of the Army of the Kingdom of Serbia started publishing a new military review, 'Ratnik', which, apart from the art of war and war literature, dealt with the science of weapons in order to inform officers about the latest achievements in military technology and to educate them as well. Serbian military thinking, including its technical aspect, did not fall behind modern trends in its European and world counterparts until 1914. The development of weaponry in Europe and the world was regularly covered on the pages of military reviews.

Comparative exergetic performance analysis for certain thermal power plants in Serbia

Directory of Open Access Journals (Sweden)

Mitrović Dejan M.

2016-01-01

Full Text Available Traditional methods of analysis and calculation of complex thermal systems are based on the first law of thermodynamics. These methods use energy balance for a system. In general, energy balances do not provide any information about internal losses. In contrast, the second law of thermodynamics introduces the concept of exergy, which is useful in the analysis of thermal systems. Exergy is a measure for assessing the quality of energy, and allows one to determine the location, cause, and real size of losses incurred as well as residues in a thermal process. The purpose of this study is to comparatively analyze the performance of four thermal power plants from the energetic and exergetic viewpoint. Thermodynamic models of the plants are developed based on the first and second law of thermodynamics. The primary objectives of this paper are to analyze the system components separately and to identify and quantify the sites having largest energy and exergy losses. Finally, by means of these analyses, the main sources of thermodynamic inefficiencies as well as a reasonable comparison of each plant to others are identified and discussed. As a result, the outcomes of this study can provide a basis for the improvement of plant performance for the considered thermal power plants.

Thermal Model Predictions of Advanced Stirling Radioisotope Generator Performance

Science.gov (United States)

Wang, Xiao-Yen J.; Fabanich, William Anthony; Schmitz, Paul C.

2014-01-01

This presentation describes the capabilities of three-dimensional thermal power model of advanced stirling radioisotope generator (ASRG). The performance of the ASRG is presented for different scenario, such as Venus flyby with or without the auxiliary cooling system.

Military and Political Studies

Directory of Open Access Journals (Sweden)

Alexey I. Podberyozkin

2014-01-01

Full Text Available Military-political issues is an important area of research work at MGIMO. The difference in this direction from the classical international specialization is that it is at the intersection of several disciplines: military science, military-technical and military-industrial as well as International Relations. A specialist in military and political issues should not only be an expert in the field of international relations and diplomacy, but also have a deep knowledge of military-technical issues to understand the basic trends in the development of scientific and technological progress and its impact on the balance of forces in the world. Global changes in the balance of power and the nature of the conflict, the emergence of new types of weapons are changing the basic methods and approaches to the art of war, which requires a science-based perspective on problem solving and multi-disciplinary approach in achieving the goals. Military and political studies allow us to understand how the development of military technology and military organization of the state affected by the political situation in the world, the national security of the country and its place in the system of international relations. Military-political research has been developing at MGIMO for a few decades. It laid down the basis for a scientific school of political-military studies. Its founding fathers were such prominent scholars of international affairs, as I.G. Usachyov, A.D. Nikonov, A.G. Arbatov, V.G. Baranovsky, V.M. Kulagin, A.N. Nikitin and other well-known experts. Their work covers a wide range of military and political issues, including the topics of arms control and disarmament, international, and especially European security, military policy, NATO, the Western military-political doctrines and their practical application. Now the lead in the development of this research at MGIMO has taken Center for Military-Political Studies, which became a concentration of relevant

Additive Manufacturing Thermal Performance Testing of Single Channel GRCop-84 SLM Components

Science.gov (United States)

Garcia, Chance P.; Cross, Matthew

2014-01-01

The surface finish found on components manufactured by sinter laser manufacturing (SLM) is rougher (0.013 - 0.0006 inches) than parts made using traditional fabrication methods. Internal features and passages built into SLM components do not readily allow for roughness reduction processes. Alternatively, engineering literature suggests that the roughness of a surface can enhance thermal performance within a pressure drop regime. To further investigate the thermal performance of SLM fabricated pieces, several GRCop-84 SLM single channel components were tested using a thermal conduction rig at MSFC. A 20 kW power source running at 25% duty cycle and 25% power level applied heat to each component while varying water flow rates between 2.1 - 6.2 gallons/min (GPM) at a supply pressure of 550 to 700 psi. Each test was allowed to reach quasi-steady state conditions where pressure, temperature, and thermal imaging data were recorded. Presented in this work are the heat transfer responses compared to a traditional machined OHFC Copper test section. An analytical thermal model was constructed to anchor theoretical models with the empirical data.

Hydrocarbon Fuel Thermal Performance Modeling based on Systematic Measurement and Comprehensive Chromatographic Analysis

Science.gov (United States)

2016-07-31

distribution unlimited Hydrocarbon Fuel Thermal Performance Modeling based on Systematic Measurement and Comprehensive Chromatographic Analysis Matthew...vital importance for hydrocarbon -fueled propulsion systems: fuel thermal performance as indicated by physical and chemical effects of cooling passage... analysis . The selection and acquisition of a set of chemically diverse fuels is pivotal for a successful outcome since test method validation and

Status Configurations, Military Service and Higher Education.

Science.gov (United States)

Wang, Lin; Elder, Glen H; Spence, Naomi J

2012-12-01

The U.S. Armed Forces offer educational and training benefits as incentives for service. This study investigates the influence of status configurations on military enlistment and their link to greater educational opportunity. Three statuses (socioeconomic status of origin, cognitive ability and academic performance) have particular relevance for life course options. We hypothesize that young men with inconsistent statuses are more likely to enlist than men with consistent status profiles, and that military service improves access to college for certain configurations. Analyses of the National Longitudinal Study of Adolescent Health (Add Health) show (1. that several status configurations markedly increased the likelihood of military enlistment and (2. within status configurations, recruits were generally more likely to enroll in higher education than nonveterans, with associate degrees being more likely.

Evaluating Security Assistance Programs: Performance Evaluation and the Expanded International Military Education and Training (E-IMET) Program

National Research Council Canada - National Science Library

Calhoun, Todd

1998-01-01

In 1991 the International Military Education and Training (IMET) program was expanded to include training programs focusing on civilian control over the military, respect for human rights, and responsible defense resource management...

Performance results of a solar greenhouse combining electrical and thermal energy production

NARCIS (Netherlands)

Sonneveld, P.J.; Swinkels, G.L.A.M.; Campen, J.B.; Tuijl, van B.A.J.; Janssen, H.J.J.; Bot, G.P.A.

2010-01-01

Performance results are given of a new type of greenhouse, which combines reflection of near infrared radiation (NIR) with electrical power generation using hybrid photovoltaic cell/thermal collector modules. Besides the generation of electrical and thermal energy, the reflection of the NIR will

14 CFR 65.117 - Military riggers or former military riggers: Special certification rule.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Military riggers or former military riggers: Special certification rule. 65.117 Section 65.117 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... Riggers § 65.117 Military riggers or former military riggers: Special certification rule. In place of the...

Effect of aluminum anodizing in phosphoric acid electrolyte on adhesion strength and thermal performance

Science.gov (United States)

Lee, Sulki; Kim, Donghyun; Kim, Yonghwan; Jung, Uoochang; Chung, Wonsub

2016-01-01

This study examined the adhesive bond strength and thermal performance of the anodized aluminum 6061 in phosphoric acid electrolyte to improve the adhesive bond strength and thermal performance for use in metal core printed circuit boards (MCPCB). The electrolyte temperature and applied voltage were altered to generate varied pore structures. The thickness, porosity and pore diameter of the anodized layer were measured. The pore morphologies were affected most by temperature, which was the driving force for ion transportation. The mechanism of adhesive bond was penetration of the epoxy into the pores. The optimal anodization conditions for maximum adhesive bond strength, 27 MPa, were 293 K and 100V. The maximum thermal conductivity of the epoxy-treated anodized layer was 1.6 W/m·K at 273 K. Compared with the epoxy-treated Al layer used for conventional MCPCBs, the epoxy-treated anodized layer showed advanced thermal performance due to a low difference of thermal resistance and high heat dissipation.

Prediction of Student Performance in Academic and Military Learning Environment: Use of Multiple Linear Regression Predictive Model and Hypothesis Testing

Science.gov (United States)

Khan, Wasi Z.; Al Zubaidy, Sarim

2017-01-01

The variance in students' academic performance in a civilian institute and in a military technological institute could be linked to the environment of the competition available to the students. The magnitude of talent, domain of skills and volume of efforts students put are identical in both type of institutes. The significant factor is the…

The Military's Business

DEFF Research Database (Denmark)

Rasmussen, Mikkel Vedby

If the military were a business, would you buy shares? Over recent years, Western armed forces, particularly the US, have been costing more yet achieving less. At the same time, austerity measures are reducing defence budgets. This book uses defence data to examine the workings of modern Western...... militaries and explore what kind of strategies can overcome this gap between input and output. Instead of focusing on military strategy, Mikkel Vedby Rasmussen seeks to draw on the ideas of business strategy to assess alternative business cases - reforming military HR to combat instability in the 'Global...

Thermal performance of a micro-combustor for micro-gas turbine system

International Nuclear Information System (INIS)

Cao, H.L.; Xu, J.L.

2007-01-01

Premixed combustion of hydrogen gas and air was performed in a stainless steel based micro-annular combustor for a micro-gas turbine system. Micro-scale combustion has proved to be stable in the micro-combustor with a gap of 2 mm. The operating range of the micro-combustor was measured, and the maximum excess air ratio is up to 4.5. The distribution of the outer wall temperature and the temperature of exhaust gas of the micro-combustor with excess air ratio were obtained, and the wall temperature of the micro-combustor reaches its maximum value at the excess air ratio of 0.9 instead of 1 (stoichiometric ratio). The heat loss of the micro-combustor to the environment was calculated and even exceeds 70% of the total thermal power computed from the consumed hydrogen mass flow rate. Moreover, radiant heat transfer covers a large fraction of the total heat loss. Measures used to reduce the heat loss were proposed to improve the thermal performance of the micro-combustor. The optimal operating status of the micro-combustor and micro-gas turbine is analyzed and proposed by analyzing the relationship of the temperature of the exhaust gas of the micro-combustor with thermal power and excess air ratio. The investigation of the thermal performance of the micro-combustor is helpful to design an improved micro-combustor

Numerical research on the thermal performance of high altitude scientific balloons

International Nuclear Information System (INIS)

Dai, Qiumin; Xing, Daoming; Fang, Xiande; Zhao, Yingjie

2017-01-01

Highlights: • A model is presented to evaluate the IR radiation between translucent surfaces. • Comprehensive ascent and thermal models of balloons are established. • The effect of IR transmissivity on film temperature distribution is unneglectable. • Atmospheric IR radiation is the primary thermal factor of balloons at night. • Solar radiation is the primary thermal factor of balloons during the day. - Abstract: Internal infrared (IR) radiation is an important factor that affects the thermal performance of high altitude balloons. The internal IR radiation is commonly neglected or treated as the IR radiation between opaque gray bodies. In this paper, a mathematical model which considers the IR transmissivity of the film is proposed to estimate the internal IR radiation. Comprehensive ascent and thermal models for high altitude scientific balloons are established. Based on the models, thermal characteristics of a NASA super pressure balloon are simulated. The effects of film IR property on the thermal behaviors of the balloon are discussed in detail. The results are helpful for the design and operation of high altitude scientific balloons.

Transient thermal performance analysis of micro heat pipes

International Nuclear Information System (INIS)

Liu, Xiangdong; Chen, Yongping

2013-01-01

A theoretical analysis of transient fluid flow and heat transfer in a triangular micro heat pipes (MHP) has been conducted to study the thermal response characteristics. By introducing the system identification theory, the quantitative evaluation of the MHP's transient thermal performance is realized. The results indicate that the evaporation and condensation processes are both extended into the adiabatic section. During the start-up process, the capillary radius along axial direction of MHP decreases drastically while the liquid velocity increases quickly at the early transient stage and an approximately linear decrease in wall temperature arises along the axial direction. The MHP behaves as a first-order LTI control system with the constant input power as the 'step input' and the evaporator wall temperature as the 'output'. Two corresponding evaluation criteria derived from the control theory, time constant and temperature constant, are able to quantitatively evaluate the thermal response speed and temperature level of MHP under start-up, which show that a larger triangular groove's hydraulic diameter within 0.18–0.42 mm is able to accelerate the start-up and decrease the start-up temperature level of MHP. Additionally, the MHP starts up fastest using the fluid of ethanol and most slowly using the working fluid of methanol, and the start-up temperature reaches maximum level for acetone and minimum level for the methanol. -- Highlights: • Transient thermal response of micro heat pipe is simulated by an improved model. • Control theory is introduced to quantify the thermal response of micro heat pipe. • Evaluation criteria are proposed to represent thermal response of micro heat pipe. • Effects of groove dimensions and working fluids on start-up of micro heat pipe are evaluated

PID temperature controller in pig nursery: improvements in performance, thermal comfort, and electricity use.

Science.gov (United States)

de Souza Granja Barros, Juliana; Rossi, Luiz Antonio; Sartor, Karina

2016-08-01

The use of smarter temperature control technologies in heating systems can optimize the use of electric power and performance of piglets. Two control technologies of a resistive heating system were assessed in a pig nursery: a PID (proportional, integral, and derivative) controller and a thermostat. The systems were evaluated regarding thermal environment, piglet performance, and use of electric power for 99 days. The heating system with PID controller improved the thermal environment conditions and was significantly (P PID-controlled heating system is more efficient in electricity use and provides better conditions for thermal comfort and animal performance than heating with thermostat.

Security surveillance challenges and proven thermal imaging capabilities in real-world applications

Science.gov (United States)

Francisco, Glen L.; Roberts, Sharon

2004-09-01

Uncooled thermal imaging was first introduced to the public in early 1980's by Raytheon (legacy Texas Instruments Defense Segment Electronics Group) as a solution for military applications. Since the introduction of this technology, Raytheon has remained the leader in this market as well as introduced commercial versions of thermal imaging products specifically designed for security, law enforcement, fire fighting, automotive and industrial uses. Today, low cost thermal imaging for commercial use in security applications is a reality. Organizations of all types have begun to understand the advantages of using thermal imaging as a means to solve common surveillance problems where other popular technologies fall short. Thermal imaging has proven to be a successful solution for common security needs such as: ¸ vision at night where lighting is undesired and 24x7 surveillance is needed ¸ surveillance over waterways, lakes and ports where water and lighting options are impractical ¸ surveillance through challenging weather conditions where other technologies will be challenged by atmospheric particulates ¸ low maintenance requirements due to remote or difficult locations ¸ low cost over life of product Thermal imaging is now a common addition to the integrated security package. Companies are relying on thermal imaging for specific applications where no other technology can perform.

Patent foramen ovale and asymptomatic brain lesions in military fighter pilots.

Science.gov (United States)

Kang, Kyung Wook; Kim, Joon-Tae; Choi, Won-Ho; Park, Won-Ju; Shin, Young Ho; Choi, Kang-Ho

2014-10-01

Previous studies have reported higher incidence of white matter lesions (WMLs) in military pilots. The anti-gravity straining maneuver, which fighter military pilots perform numerously during a flight is identical to the valsalva maneuver. We sought to investigate the prevalence of right-to-left shunt (RLS) associated with WMLs in military pilots. A prospective study was performed involving military pilots who visited the Airomedical Center. The pilots underwent brain magnetic resonance imaging (MRI) scan and transcranial Doppler (TCD) with intravenous injection of agitated saline solution for the detection of RLS. Periventricular WMLs (PVWMLs) on MRI were graded using Fazeka's scale, and deep WMLs (DWMLs) were graded using Scheltens's scale. This study included 81 military pilots. RLS on TCD was observed less frequently in non-fighter pilots than in fighter pilots (35.5% vs. 64.5%, p=0.011). Fighter pilot was an independently associated factor with RLS on the TCD. DWMLs were independently associated with RLSs through a patent foramen ovale (PFO) (OR 3.507, 95% CI 1.223-10.055, p=0.02). The results suggest that DWMLs in military pilots may significantly be associated with RLS via PFO. Additional investigations are warranted. Copyright © 2014 Elsevier B.V. All rights reserved.

Development and application of diurnal thermal modeling for camouflage, concealment, and deception

Science.gov (United States)

Rodgers, Mark L. B.

2000-07-01

The art of camouflage is to make a military asset appear to be part of the natural environment: its background. In order to predict the likely performance of countermeasures in attaining this goal it is necessary to model the signatures of targets, backgrounds and the effect of countermeasures. A library of diurnal thermal models has been constructed covering a range of backgrounds from vegetated and non- vegetated surfaces to snow cover. These models, originally developed for Western Europe, have been validated successfully for theatres of operation from the arctic to the desert. This paper will show the basis for and development of physically based models for the diurnal thermal behavior both of these backgrounds and for major passive countermeasures: camouflage nets and continuous textile materials. The countermeasures set up significant challenges for the thermal modeler with their low but non-zero thermal inertial and the extent to which they influence local aerodynamic behavior. These challenges have been met and the necessary extensive validation has shown the ability of the models to predict successfully the behavior of in-service countermeasures.

Iraqi Military Academies

Directory of Open Access Journals (Sweden)

Nodar Z. Mossaki

2015-03-01

Full Text Available The article analyzes the system of training of officers in military academies in Iraq – in Zakho, Qalacholan, ar-Rustamiyah and an-Nasiriyah. The author describes the history of creation, process of evolution, challenges and features of training in these colleges. Particular attention paid to military academies in the territory of Iraqi Kurdistan, which actually do not obey the central government of Iraq, however, have the highest level of training. Currently, Iraq's military academies operate on the basis of the NATO standards. Iraqi military academies paid miuch attention to the specifics of the military and political situation in Iraq – counterinsurgency and counterterrorism operations, patrolling cities, fighting in an urban environment etc. Significant place in the curriculum take the courses contributing to the formation of pro-Western sentiment.

High thermal performance lithium-ion battery pack including hybrid active–passive thermal management system for using in hybrid/electric vehicles

International Nuclear Information System (INIS)

Fathabadi, Hassan

2014-01-01

In this study, a novel Li-ion battery pack design including hybrid active–passive thermal management system is presented. The battery pack is suitable for using in hybrid/electric vehicles. Active part of the hybrid thermal management system uses distributed thin ducts, air flow and natural convection as cooling media while the passive part utilizes phase change material/expanded graphite composite (PCM/EG) as cooling/heating component to optimize the thermal performance of the proposed battery pack. High melting enthalpy of PCM/EG composite together with melting of PCM/EG composite at the temperature of 58.9 °C remains the temperature distribution of the battery units in the desired temperature range (below 60 °C). The temperature and voltage distributions in the proposed battery pack design consisting of battery units, distributed thin ducts and PCM/EG composite are calculated by numerical solving of the related partial differential equations. Simulation results obtained by writing M-files code in Matlab environment and plotting the numerical data are presented to validate the theoretical results. A comparison between the thermal and physical characteristics of the proposed battery pack and other latest works is presented that explicitly proves the battery pack performance. - Highlights: • Novel Li-ion battery pack including active and passive thermal management systems. • The battery pack has high thermal performance for ambient temperatures until 55 °C. • Uniform temperature and voltage distributions. • The maximum observed temperature in each battery unit is less than other works. • The maximum temperature dispersion in each battery is less than other works

A JURIDICAL-ADMINISTRATIVE COMPARISON BETWEEN THE MILITARY AND THE MEDICAL OPERATION

Directory of Open Access Journals (Sweden)

Georgel RUSU

2016-03-01

Full Text Available To bring together the word operation and opera and/or accomplishing an opera is not at all improper. Defining a (military operation as ”the total amount of the military actions performed by large operative and strategic units, according to an unique plan, for attaining an operative or strategic objective....”[1], coldly and exhaustively developed along almost two pages, may provide sufficient arguments for correctly anchoring the action within the domain of military practice, in spite of the shortcoming of not having a more synthetic form, with valid landmarks for other disciplines, as well. Frequently, both the medical and the military operations exceed their routine, deserving artistic appreciations. It is not accidental that analysis and preparation of any military combat includes the field of military art, defined as ”a compounding part of the military science, a specialized domain of organization and management of armed conflicts. It includes both the principles, methods, procedures and rules for the preparation and development of military actions, and the personal endowments (talent, mastership, skill expected from the part of leaders and troops for attaining success in the battle...”[2] More than that, the operative art is defined as ”a component of military art ... created and developed as an intermediary domain between strategy and tactics...”[3]. Continuing to lay stress on the parallelism to which the study is devoted, the author considers that actions that may be related to or may be appreciated as possessing artistic characteristics occur even beyond the field of aesthetic or reparatory surgery. The definitions provided by medical dictionaries do not eliminate, yet encourage similarities. The operation is ”s.f./operation, (Lat. operatio, -onis = work, operation, derived from operari = to work, and opus, operis = labour, work, a medical act performed by the surgeon with his hands, by means of adequate instruments, for

A cost-effectiveness analysis of typhoid fever vaccines in US military personnel.

Science.gov (United States)

Warren, T A; Finder, S F; Brier, K L; Ries, A J; Weber, M P; Miller, M R; Potyk, R P; Reeves, C S; Moran, E L; Tornow, J J

1996-11-01

Typhoid fever has been a problem for military personnel throughout history. A cost-effectiveness analysis of typhoid fever vaccines from the perspective of the US military was performed. Currently 3 vaccine preparations are available in the US: an oral live Type 21A whole cell vaccine; a single-dose parenteral, cell subunit vaccine; and a 2-dose parenteral heat-phenol killed, whole cell vaccine. This analysis assumed all vaccinees were US military personnel. Two pharmacoeconomic models were developed, one for personnel who have not yet been deployed, and the other for personnel who are deployed to an area endemic for typhoid fever. Drug acquisition, administration, adverse effect and lost work costs, as well as the costs associated with typhoid fever, were included in this analysis. Unique military issues, typhoid fever attack rates, vaccine efficacy, and compliance with each vaccine's dosage regimen were included in this analysis. A sensitivity analysis was performed to test the robustness of the models. Typhoid fever immunisation is not cost-effective for US military personnel unless they are considered imminently deployable or are deployed. The most cost-effective vaccine for US military personnel is the single-dose, cell subunit parenteral vaccine.

Aviator's Fluid Balance During Military Flight.

Science.gov (United States)

Levkovsky, Anna; Abot-Barkan, Sivan; Chapnik, Leah; Doron, Omer; Levy, Yuval; Heled, Yuval; Gordon, Barak

2018-02-01

A loss of 1% or more of bodyweight due to dehydration has a negative effect on cognitive performance, which could critically affect flight safety. There is no mention in the literature concerning the amounts of military pilots' fluid loss during flight. The aim of this study was to quantify fluid loss of pilots during military flight. There were 48 aviators (mean age 23.9) from the Israeli Air Force who participated in the study, which included 104 training flights in various flight platforms. Bodyweight, urine specific gravity, and environmental heat strain were measured before and after each flight. Fluid loss was calculated as the weight differences before and after the flight. We used a univariate and one-way ANOVA to analyze the effect of different variables on the fluid loss. The mean fluid loss rate was 462 ml · h-1. The results varied among different aircraft platforms and depended on flight duration. Blackhawk pilots lost the highest amount of fluids per flight, albeit had longer flights (mean 108 min compared to 35.5 in fighter jets). Jet fighter pilots had the highest rate of fluid loss per hour of flight (up to 692 ml, extrapolated). Overall, at 11 flights (11%) aircrew completed their flight with a meaningful fluid loss. We conclude that military flights may be associated with significant amount of fluid loss among aircrew.Levkovsky A, Abot-Barkan S, Chapnik L, Doron O, Levy Y, Heled Y, Gordon B. Aviator's fluid balance during military flight. Aerosp Med Hum Perform. 2018; 89(2):9498.

Computational Analysis on Performance of Thermal Energy Storage (TES) Diffuser

Science.gov (United States)

Adib, M. A. H. M.; Adnan, F.; Ismail, A. R.; Kardigama, K.; Salaam, H. A.; Ahmad, Z.; Johari, N. H.; Anuar, Z.; Azmi, N. S. N.

2012-09-01

Application of thermal energy storage (TES) system reduces cost and energy consumption. The performance of the overall operation is affected by diffuser design. In this study, computational analysis is used to determine the thermocline thickness. Three dimensional simulations with different tank height-to-diameter ratio (HD), diffuser opening and the effect of difference number of diffuser holes are investigated. Medium HD tanks simulations with double ring octagonal diffuser show good thermocline behavior and clear distinction between warm and cold water. The result show, the best performance of thermocline thickness during 50% time charging occur in medium tank with height-to-diameter ratio of 4.0 and double ring octagonal diffuser with 48 holes (9mm opening ~ 60%) acceptable compared to diffuser with 6mm ~ 40% and 12mm ~ 80% opening. The conclusion is computational analysis method are very useful in the study on performance of thermal energy storage (TES).

Thermal Performance of Precast Concrete Sandwich Panel (PCSP) Design for Sustainable Built Environment

Science.gov (United States)

Ern, Peniel Ang Soon; Ling, Lim Mei; Kasim, Narimah; Hamid, Zuhairi Abd; Masrom, Md Asrul Nasid Bin

2017-10-01

Malaysia’s awareness of performance criteria in construction industry towards a sustainable built environment with the use of precast concrete sandwich panel (PCSP) system is applied in the building’s wall to study the structural behaviour. However, very limited studies are conducted on the thermal insulation of exterior and interior panels in PCSP design. In hot countries such as Malaysia, proper designs of panel are important to obtain better thermal insulation for building. This study is based on thermal performance of precast concrete sandwich panel design for sustainable built environment in Malaysia. In this research, three full specimens, which are control specimen (C), foamed concrete (FC) panels and concrete panels with added palm oil fuel ash (FC+ POFA), where FC and FC+POFA sandwiched with gypsum board (G) were produced to investigate their thermal performance. Temperature difference of exterior and interior surface of specimen was used as indicators of thermal-insulating performance of PCSP design. Heat transfer test by halogen lamp was carried out on three specimens where the exterior surface of specimens was exposed to the halogen lamp. The temperature reading of exterior and interior surface for three specimens were recorded with the help of thermocouple. Other factors also studied the workability, compressive strength and axial compressive strength of the specimens. This study has shown that FC + POFA specimen has the strength nearer to normal specimen (C + FC specimen). Meanwhile, the heat transfer results show that the FC+POFA has better thermal insulation performance compared to C and FC specimens with the highest temperature difference, 3.4°C compared to other specimens. The results from this research are useful to be implemented in construction due to its benefits such as reduction of energy consumption in air-conditioning, reduction of construction periods and eco-friendly materials.

Measure the effects of thermal discomfort on the performance of office work

DEFF Research Database (Denmark)

Lan, L.; Wargocki, P.; Lian, Z.W.

2011-01-01

Accuracy and speed are the two distinct aspects of human performance. A method was proposed by which the speed and accuracy were integrated into one measure by designing the tasks in such a way that the participants can only proceed to the next test when the task was performed without errors....... The method was examined through a subjective experiment with thermal environment as the prototypical example. The experimental results indicate that the negative effects of thermal discomfort on human performance were evaluated well by the tasks designed with the proposed method. It provides a useful tool...... for better measurement of human performance and helps to facilitate the development of quantitative relationship between IEQ and productivity....

Evaluating the interior thermal performance of mosques in the tropical environment

Science.gov (United States)

Nordin, N. I.; Misni, A.

2018-02-01

This study introduces the methodology applied in conducting data collection and data analysis. Data collection is the process of gathering and measuring information on targeted variables in an established systematic method. Qualitative and quantitative methods are combined in collecting data from government departments, site experiments and observation. Furthermore, analysing the indoor thermal performance data in the heritage and new mosques were used thermal monitoring tests, while validation will be made by meteorology data. Origin 8 version of the software is used to analyse all the data. Comparison techniques were applied to analyse several factors that influence the indoor thermal performance of mosques, namely building envelope include floor area, opening, and material used. Building orientation, location, surrounding vegetation and water elements are also recorded as supported building primary data. The comparison of primary data using these variables for four mosques include heritage and new buildings were revealed.

Determining the Return of Energy Efficiency Investments in Domestic and Deployed Military Installations

National Research Council Canada - National Science Library

Gammache, Nathan J

2007-01-01

...: the use of Energy Savings Performance Contracts to fund energy efficiency improvements at domestic military installations, and the use of waste to energy generators at remote, deployed military installations...

Thermal performance of a linear Fresnel reflector solar concentrator PV/T energy systems

Energy Technology Data Exchange (ETDEWEB)

Gomaa, Mohamed R. [State Engineering University of Armenia (Armenia)], E-Mail: Dmoh_elbehary@yahoo.com

2011-07-01

This is a report on an investigation of photovoltaic/thermal (PV/T) collectors. Solar energy conversion efficiency was increased by taking advantage of PV/T collectors and low solar concentration technologies, combined into a PV/T system operated at elevated temperature. The main novelty is the coupling of a linear Fresnel mirror reflecting concentrator with a channel PV/T collector. Concentrator PV/T collectors can function at temperatures over 100 degrees celsius, and thus thermal energy can be made to drive processes such as refrigeration, desalination and steam production. Solar system analytical thermal performance gives efficiency values over 60%. Combined electric and thermal (CET) efficiency is high. A combined electric and heat power for the linear fresnel reflector approach that employs high performance CPV technology to produce both electricity and thermal energy at low to medium temperatures is presented. A well-functioning PV/T system can be designed and constructed with low concentration and a total efficiency of nearly 80% can be attained.

The military dimension of a more Militant Russia

Directory of Open Access Journals (Sweden)

Julian Cooper

2016-06-01

Full Text Available The article analyses the development of the military dimension of Russia's economy over the past decade or more, including the significant growth of military expenditure and its principal driver, spending on the ambitious state armament programme to 2020. For the first time for almost twenty-five years Russia once again possesses capable armed forces. With greater economic and military strength Russia's leadership now feels able to be more assertive, even militant, on the world stage. These developments threaten to be constrained by the poor performance of the economy, facing the government with a policy challenge. However, for Russia and the main Western powers there can be no going back to the status quo ante.

Status Configurations, Military Service and Higher Education

Science.gov (United States)

Wang, Lin; Elder, Glen H.; Spence, Naomi J.

2012-01-01

The U.S. Armed Forces offer educational and training benefits as incentives for service. This study investigates the influence of status configurations on military enlistment and their link to greater educational opportunity. Three statuses (socioeconomic status of origin, cognitive ability and academic performance) have particular relevance for life course options. We hypothesize that young men with inconsistent statuses are more likely to enlist than men with consistent status profiles, and that military service improves access to college for certain configurations. Analyses of the National Longitudinal Study of Adolescent Health (Add Health) show (1. that several status configurations markedly increased the likelihood of military enlistment and (2. within status configurations, recruits were generally more likely to enroll in higher education than nonveterans, with associate degrees being more likely. PMID:24511161

Stress fractures in military training

International Nuclear Information System (INIS)

Jofre, M.J.; Sierralta, M.P.

2002-01-01

During military training, the incidence of overuse injuries like stress fractures increase. The aim of the study was to investigate the utility of bone scan in a military population with clinical suspected stress fractures or periostitis. Material and methods: A three-year retrospective analysis was made on patients who were clinically diagnosed with stress fractures at the Military Hospital Nuclear Medicine Department. Thirty-seven patients were studied (mean age 23. +/- 8 y.o; 31 males), 28 cases of which (76%) had tibial stress syndrome. Other localizations were lumbar spine, femoral, fibular, tarsal or metatarsal. Bone scintigraphy was performed injecting 1036 MBq of Tc99m-MDP i.v. Whole body images and lateral projections of lower extremities were done. Results: Bone scan in tibial syndrome was positive for 23 cases (82%), 65% of them were bilateral and 13% also had femoral injuries. X-rays were done in 10 cases and were all negative. In other localizations, the bone scans were negative, but demonstrated other degenerative lesions. All stress fractures were conservatively treated with non-steroidal anti-inflammatories and suspension of physical activity. Conclusions: Bone scan is a reliable confirmatory tool for tibial stress syndrome diagnosis. In addition, it helps to determine both the severity and extension of the injury as well as support the indication of rest in the military population

Stress fractures in military training

Energy Technology Data Exchange (ETDEWEB)

Jofre, M J; Sierralta, M P [Military Hospital Nuclear Medicine Department, Santiago (Chile)

2002-09-01

During military training, the incidence of overuse injuries like stress fractures increase. The aim of the study was to investigate the utility of bone scan in a military population with clinical suspected stress fractures or periostitis. Material and methods: A three-year retrospective analysis was made on patients who were clinically diagnosed with stress fractures at the Military Hospital Nuclear Medicine Department. Thirty-seven patients were studied (mean age 23. +/- 8 y.o; 31 males), 28 cases of which (76%) had tibial stress syndrome. Other localizations were lumbar spine, femoral, fibular, tarsal or metatarsal. Bone scintigraphy was performed injecting 1036 MBq of Tc99m-MDP i.v. Whole body images and lateral projections of lower extremities were done. Results: Bone scan in tibial syndrome was positive for 23 cases (82%), 65% of them were bilateral and 13% also had femoral injuries. X-rays were done in 10 cases and were all negative. In other localizations, the bone scans were negative, but demonstrated other degenerative lesions. All stress fractures were conservatively treated with non-steroidal anti-inflammatories and suspension of physical activity. Conclusions: Bone scan is a reliable confirmatory tool for tibial stress syndrome diagnosis. In addition, it helps to determine both the severity and extension of the injury as well as support the indication of rest in the military population.

Performance Testing of Thermal Cutting Systems for Sweet Pepper Harvesting Robot in Greenhouse Horticulture

Science.gov (United States)

Bachche, Shivaji; Oka, Koichi

2013-03-01

This paper proposes design of end-effector and prototype of thermal cutting system for harvesting sweet peppers. The design consists of two parallel gripper bars mounted on a frame connected by specially designed notch plate and operated by servo motor. Based on voltage and current, two different types of thermal cutting system prototypes; electric arc and temperature arc respectively were developed and tested for performance. In electric arc, a special electric device was developed to obtain high voltage to perform cutting operation. At higher voltage, electrodes generate thermal arc which helps to cut stem of sweet pepper. In temperature arc, nichrome wire was mounted between two electrodes and current was provided directly to electrodes which results in generation of high temperature arc between two electrodes that help to perform cutting operation. In both prototypes, diameters of basic elements were varied and the effect of this variation on cutting operation was investigated. The temperature arc thermal system was found significantly suitable for cutting operation than electric arc thermal system. In temperature arc thermal cutting system, 0.5 mm nichrome wire shows significant results by accomplishing harvesting operation in 1.5 seconds. Also, thermal cutting system found suitable to increase shelf life of fruits by avoiding virus and fungal transformation during cutting process and sealing the fruit stem. The harvested sweet peppers by thermal cutting system can be preserved at normal room temperature for more than 15 days without any contamination.

Environmental Assessment: Gulf Power Company Military Point Transmission Line Project

Science.gov (United States)

2014-05-12

1500.4. 1.4. 1 Geology No geological hazards, seismic risks, or unstable slopes occur in the vicinity of Military Point on Tyndall AFB. Therefore, the...with sand grout to fill any voids within the casing and provide thermal insulation for the electric cable. Lengths greater than 3,000 feet would be...devices designed to either insulate or isolate potential contact points have. been recommended to minimize the risk of eagle electrocution, which are

A global fouling factor methodology for analyzing steam generator thermal performance degradation

International Nuclear Information System (INIS)

Kreider, M.A.; White, G.A.; Varrin, R.D.

1998-01-01

Over the past few years, steam generator (SG) thermal performance degradation has led to decreased plant efficiency and power output at numerous PWR nuclear power plants with recirculating-type SGs. The authors have developed and implemented methodologies for quantitatively evaluating the various sources of SG performance degradation, both internal and external to the SG pressure boundary. These methodologies include computation of the global fouling factor history, evaluation of secondary deposit thermal resistance using deposit characterization data, and consideration of pressure loss causes unrelated to the tube bundle, such as hot-leg temperature streaming and SG moisture separator performance. In order to evaluate the utility of the global fouling factor methodology, the authors performed case studies for a number of PWR SG designs. Key results from two of these studies are presented here. Uncertainty analyses were performed to determine whether the calculated fouling factor for each plant represented significant fouling or whether uncertainty in key variables (e.g., steam pressure or feedwater flow rate) could be responsible for calculated fouling. The methodology was validated using two methods: by predicting the SG pressure following chemical cleaning at San Onofre 2 and also by performing a sensitivity study with the industry-standard thermal-hydraulics code ATHOS to investigate the effects of spatially varying tube scale distributions. This study indicated that the average scale thickness has a greater impact on fouling than the spatial distribution, showing that the assumption of uniform resistance inherent to the global fouling factor is reasonable. In tandem with the fouling-factor analyses, a study evaluated for each plant the potential causes of pressure loss. The combined results of the global fouling factor calculations and the pressure loss evaluations demonstrated two key points: 1) that the available thermal margin against fouling, which can

Unconventional Military Advising Mission Conducted by Conventional US Military Forces

OpenAIRE

Hajjar, Remi M.

2016-01-01

This article examines how and why many contemporary US mainstream military advisors—as compared to Special Forces advisors—often work from a position of disadvantage when conducting unconventional advising missions. Post-9/11 deployments to Iraq and Afghanistan have caused the US military to adapt to myriad complexities, including a renewed need for the widespread execution of the unconventional military advising mission by the Special Forces and conventional units. Although Special Forces ty...

What Military Officers Need to Know About Civil-Military Relations

Science.gov (United States)

2012-04-01

2012, Vol. 65, No. 2 Mackubin Thomas Owens ivil-military relations describe the interactions among the people of a state, the institutions of that...civilians for the unexpect- edly difficult occupation of Iraq,” one close observer—U.S. Army major Isaiah Wilson III, an official historian of the...U.S. Civil- Military Relations. 4. I have addressed these questions in depth in Mackubin Thomas Owens, US Civil-Military Relations after 9/11

Thermal Performance Analysis of Staging Effect of Solar Thermal Absorber with Cross Design

International Nuclear Information System (INIS)

Amir Abdul Razak; Zafri Azran Abdul Majid; Mohd Hafidz Ruslan; Kamaruzzaman Sopian

2015-01-01

The type and shape of solar thermal absorber materials will impact on the operating temperature and thermal energy storage effect of a solar air thermal collector. For a standard flat-plate design, energy gain can be increased by expanding the thermal absorber area along the collector plane, subject to area limitation. This paper focuses on the staging effect of a metal hollow square rod absorber of aluminium, stainless steel, and a combination of the two with a cross design, for the heat gain and temperature characteristics of a solar air collector. Experiments were carried out with three cross design set-ups, with 30 minutes of heating and cooling, phase, respectively, under 485 W/ m 2 solar irradiance value, and at a constant air speed at 0.38 m/ s. One set aluminium set-up delivered the highest output temperature of 41.8 degree Celsius, followed by two-sets aluminium and one aluminium set + one stainless steel set at 39.3 and 38.2 degree Celsius, respectively. The lowest peak temperature is recorded on three sets of the aluminium absorber at 35 degree Celsius. The bi-metallic set-up performed better than the two aluminium set-up where each set-up obtained a temperature drop against heat gain gradient value of -0.4186 degree Celsius/ W and -0.4917 degree Celsius/ W, respectively. Results concluded that by increasing the number of sets, the volume and surface areas of the absorber material are also increased, and lead to a decrease in peak temperature output for each increase of sets. (author)

Computational Analysis on Performance of Thermal Energy Storage (TES) Diffuser

International Nuclear Information System (INIS)

Adib, M A H M; Ismail, A R; Kardigama, K; Salaam, H A; Ahmad, Z; Johari, N H; Anuar, Z; Azmi, N S N; Adnan, F

2012-01-01

Application of thermal energy storage (TES) system reduces cost and energy consumption. The performance of the overall operation is affected by diffuser design. In this study, computational analysis is used to determine the thermocline thickness. Three dimensional simulations with different tank height-to-diameter ratio (HD), diffuser opening and the effect of difference number of diffuser holes are investigated. Medium HD tanks simulations with double ring octagonal diffuser show good thermocline behavior and clear distinction between warm and cold water. The result show, the best performance of thermocline thickness during 50% time charging occur in medium tank with height-to-diameter ratio of 4.0 and double ring octagonal diffuser with 48 holes (9mm opening ∼ 60%) acceptable compared to diffuser with 6mm ∼ 40% and 12mm ∼ 80% opening. The conclusion is computational analysis method are very useful in the study on performance of thermal energy storage (TES).

Performance of stratified thermal-storage system for Oliver Springs Elementary School. Progress report

Energy Technology Data Exchange (ETDEWEB)

Reid, R.L.; Bedinger, A.F.G.

1981-01-01

A progress report is given on the performance of a stratified thermal storage system coupled with a heat recovery refrigeration machine designed to provide space heating, cooling and service water heating. Water storage tanks utilizing a flexible membrane to resist temperature blending will be used as the thermal storage element. The two design goals of the heat recovery and thermal energy storage system are (1) to minimize the need to purchase energy for space heating and cooling and water heating and (2) to minimize electrical demand. An automatic data acquisition system will be used for system performance and data gathering. Data collection is expected to begin in September, 1981.

The Military's Business

DEFF Research Database (Denmark)

Rasmussen, Mikkel Vedby

If the military were a business, would you buy shares? Over recent years, Western armed forces, particularly the US, have been costing more yet achieving less. At the same time, austerity measures are reducing defence budgets. This book uses defence data to examine the workings of modern Western...... militaries and explore what kind of strategies can overcome this gap between input and output. Instead of focusing on military strategy, Mikkel Vedby Rasmussen seeks to draw on the ideas of business strategy to assess alternative business cases - reforming military HR to combat instability in the 'Global...... to fit within a nation's overall national security system without ever-increasing budgets....

Alternative High Performance Polymers for Ablative Thermal Protection Systems

Science.gov (United States)

Boghozian, Tane; Stackpoole, Mairead; Gonzales, Greg

2015-01-01

Ablative thermal protection systems are commonly used as protection from the intense heat during re-entry of a space vehicle and have been used successfully on many missions including Stardust and Mars Science Laboratory both of which used PICA - a phenolic based ablator. Historically, phenolic resin has served as the ablative polymer for many TPS systems. However, it has limitations in both processing and properties such as char yield, glass transition temperature and char stability. Therefore alternative high performance polymers are being considered including cyanate ester resin, polyimide, and polybenzoxazine. Thermal and mechanical properties of these resin systems were characterized and compared with phenolic resin.

Ballistic Performance of Porous-Ceramic, Thermal-Protection-Systems

Science.gov (United States)

Christiansen, E. L.; Davis, B. A.; Miller, J. E.; Bohl, W. E.; Foreman, C. D.

2009-01-01

Porous-ceramic, thermal protection systems are used heavily in current reentry vehicles like the Space Shuttle and are currently being proposed for the next generation of manned spacecraft, Orion. These materials insulate the structural components of a spacecraft against the intense thermal environments of atmospheric reentry. Furthermore, these materials are also highly exposed to space environmental hazards like meteoroid and orbital debris impacts. This paper discusses recent impact testing up to 9 km/s, and the findings of the influence of material equation-of-state on the simulation of the impact event to characterize the ballistic performance of these materials. These results will be compared with heritage models1 for these materials developed from testing at lower velocities. Assessments of predicted spacecraft risk based upon these tests and simulations will also be discussed.

Thermal performance test for steam turbine of nuclear power plants

International Nuclear Information System (INIS)

Bu Yubing; Xu Zongfu; Wang Shiyong

2014-01-01

Through study of steam turbine thermal performance test of CPR1000 nuclear power plant, we solve the enthalpy calculation problems of the steam turbine in wet steam zone using heat balance method which can help to figure out the real overall heat balance diagram for the first time, and we develop a useful software for thermal heat balance calculation. Ling'ao phase II as an example, this paper includes test instrument layout, system isolation, risk control, data acquisition, wetness measurement, heat balance calculation, etc. (authors)

The Importance of Military Cultural Competence.

Science.gov (United States)

Meyer, Eric G; Writer, Brian W; Brim, William

2016-03-01

Military cultural competence has recently gained national attention. Experts have posited that limited outcomes in the treatment of posttraumatic stress disorder and depression in the military may be related to limited familiarity with the military. National surveys have indicated low military cultural competence among providers and limited educational efforts on military culture or pertinent military pathology in medical schools and residency training programs. Military families, with their own unique military cultural identity, have been identified as a population with increased risks associated with deployment. In response to these findings, several curricula regarding military culture have been established and widely distributed. Assessments of military cultural competence have also been developed. The clinical impact of enhanced cultural competence in general has thus far been limited. The military, however, with its highly prescribed cultural identity, may be a model culture for further study.

Impact of Military Lifestyle on Military Spouses' Educational and Career Goals

Science.gov (United States)

Ott, Laura E.; Kellley Morgan, Jessica; Akroyd, H. Duane

2018-01-01

The military lifestyle imposes unique challenges for military spouses in regards to their education and careers. To help alleviate these challenges, military spouses are encouraged to pursue portable career paths. This causes one to question whether spouses desire these portable careers and what influences spouses place on pursuing specific…

Deployment of military mothers: supportive and nonsupportive military programs, processes, and policies.

Science.gov (United States)

Goodman, Petra; Turner, Annette; Agazio, Janice; Throop, Meryia; Padden, Diane; Greiner, Shawna; Hillier, Shannon L

2013-07-01

Military mothers and their children cope with unique issues when mothers are deployed. In this article, we present mothers' perspectives on how military resources affected them, their children, and their caregivers during deployment. Mothers described beneficial features of military programs such as family readiness groups and behavioral health care, processes such as unit support, and policies on length and timing of deployments. Aspects that were not supportive included inflexibility in family care plans, using personal leave time and funds for transporting children, denial of release to resolve caretaker issues, and limited time for reintegration. We offer recommendations for enhanced support to these families that the military could provide. Reprint & Copyright © 2013 Association of Military Surgeons of the U.S.

Fuel cells for military applications - an overview of the DERA programme

International Nuclear Information System (INIS)

Lakeman, J.B.; Green, K.J.; Mepsted, G.O.; Browning, D.J.

2000-01-01

DERA is investigating fuel cells at all sizes for military applications, but two applications stand out: man-portable power and hybrid electric vehicles. The future fighting soldier will have various electrical equipments in order to maximise his combat effectiveness. Although electronic circuitry is becoming increasingly efficient, the soldier's power budget will significantly increase as more equipments are added and higher performances are specified. Consequently, there is a pressing need for high performance, man-portable power sources to replace the traditional, low performance, rechargeable nickel-cadmium battery. The paper reports a novel, potentially low cost, simple to construct, lightweight, polymer electrolyte membrane fuel cell (PEMFC) being developed at DERA Haslar as well as briefly mentioning alternatives. Another key application area could be military vehicles, both terrestrial and marine, where a fuel cell could be used as apart of a hybrid power train. The success of the fuel cell in military HEVs will depend on its ability to utilise a military logistic fuel, namely diesel. Two fuel cell options are described, which are being investigated by DERA: the high temperature proton conducting fuel cell (HTPCFC) and the high power PEMFC. (author)

Detection of dysbaric osteonecrosis in military divers using magnetic resonance imaging

International Nuclear Information System (INIS)

Bolte, H.; Heller, M.; Reuter, M.; Koch, A.; Tetzlaff, K.; Bettinghausen, E.

2005-01-01

This was a controlled cross-sectional study to investigate the prevalence of dysbaric osteonecrosis (DON) in military divers. MRI examinations of the large joints and adjacent bones were performed in a cross-sectional group of 32 highly experienced military divers and 28 non-divers matched for age and anthropometric data. Additional plain radiographs and follow-up controls were performed in all persons with signs certain or suspicious of DON. In two subject groups (one of divers and one of non-divers), lesions characteristic of DON were detected. From this controlled study, it may be concluded that MRI is a highly sensitive method to detect signs of osteonecrosis. It could be shown that the prevalence of bone lesions characteristic of osteonecrosis in highly experienced military divers is not higher than in non-diving subjects of comparable age. The outcome of this comparably small study group fits to the results of previous extensive studies performed with radiographs. The detected low incidence of DON in this collective may be due to the fact that military divers follow stricter selection criteria, decompression schemes and medical surveillance than commercial divers. (orig.)

CFD investigations of data centers’ thermal performance for different configurations of CRACs units and aisles separation

Directory of Open Access Journals (Sweden)

S.A. Nada

2016-06-01

Full Text Available The thermal performance of data centers is numerically studied for different configurations of computer room air conditioning (CRAC units and physical separations of cold and hot aisles. Temperature distribution, air flow characteristics and thermal management of data centers racks array are predicted and evaluated for the different arrangements. Measureable performance indices: supply/return heat index (SHI/RHI, return temperature index (RTI and return cooling index (RCI are used to measure the thermal management effectiveness of data center racks. The results showed that: (i hot air recirculation, cold air bypass and the measurable performance indices of the racks strongly depend on the racks location in the racks array, (ii the CRACs units layout affects the thermal managements of the racks array especially the sides and middle racks in the array, and (iii using cold aisle containments enhances the thermal performance of the data center.

Thermal performance of Egypt's research reactor core (ET-RR-1)

International Nuclear Information System (INIS)

Khattab, M.; Mariy, A.

1986-01-01

The steady state thermal performance of the ET-RR-1 core system is theoretically investigated by different models describing the heat flux and the coolant mass flow rate. The magnitude of the heat generated by a fuel element depends upon its position in the core. Normal and uniform distributions for heat flux and coolant mass flow rate are considered. The clad and coolant temperatures at different core positions are evaluated and compared with the experimental measurements at different operating conditions. The results indicated large discrepancy between the predicted and the experimental results. Therefore, the previous models and the experimental results are evaluated in order to develop the best model that describes the thermal performance of the ET-RR-1 core. The adapted model gives 99.5% significant confidence limit. The effect of increasing the heat flux or decreasing the mass flow rate by 20% from its maximum recommended operating condition is tested and discussed. Also, the thermal behaviour towards increasing the reactor power more than its maximum operating condition is discussed. The present work could also be used in extending the investigation to other PWR reactor operating conditions

IMPULSE---an advanced, high performance nuclear thermal propulsion system

International Nuclear Information System (INIS)

Petrosky, L.J.; Disney, R.K.; Mangus, J.D.; Gunn, S.A.; Zweig, H.R.

1993-01-01

IMPULSE is an advanced nuclear propulsion engine for future space missions based on a novel conical fuel. Fuel assemblies are formed by stacking a series of truncated (U, Zr)C cones with non-fueled lips. Hydrogen flows radially inward between the cones to a central plenum connected to a high performance bell nozzle. The reference IMPULSE engine rated at 75,000 lb thrust and 1800 MWt weighs 1360 kg and is 3.65 meters in height and 81 cm in diameter. Specific impulse is estimated to be 1000 for a 15 minute life at full power. If longer life times are required, the operating temperature can be reduced with a concomitant decrease in specific impulse. Advantages of this concept include: well defined coolant paths without outlet flow restrictions; redundant orificing; very low thermal gradients and hence, thermal stresses, across the fuel elements; and reduced thermal stresses because of the truncated conical shape of the fuel elements

Thermal Performance of the LHC Short Straight Section Cryostat

CERN Document Server

Bergot, J B; Nielsen, L; Parma, Vittorio; Rohmig, P; Roy, E

2002-01-01

The LHC Short Straight Section (SSS) cryostat houses and thermally protects in vacuum the cold mass which contains a twin-aperture superconducting quadrupole magnet and superconducting corrector magnets operating at 1.9 K in superfluid helium. In addition to mechanical requirements, the cryostat is designed to minimize the heat in-leak from the ambient temperature to the cold mass. Mechanical components linking the cold mass to the vacuum vessel such as support posts and an insulation vacuum barrier are designed to have minimum heat conductivity with efficient thermalisations for heat interception. Heat in-leak by radiation is reduced by employing multilayer insulation wrapped around the cold mass and an actively cooled aluminium thermal shield. The recent commissioning and operation of two SSS prototypes in the LHC Test String 2 have given a first experimental validation of the thermal performance of the SSS cryostat in nominal operating conditions. Temperature sensors mounted in critical locations provide a...

Thermal performance of the MFTF magnets

International Nuclear Information System (INIS)

VanSant, J.H.

1983-01-01

A yin-yang pair of liquid-helium (LHe) cooled, superconducting magnets were tested last year at the Lawrence Livermore National Laboratory (LLNL) as part of a series of tests with the Mirror Fusion Test Facility (MFTF). These tests were performed to determine the success of engineering design used in major systems of the MFTF and to provide a technical base for rescoping from a single-mirror facility to the large tandem-mirror configuration (MFTF-B) now under construction. The magnets were cooled, operated at their design current and magnetic field, and warmed to atmospheric temperature. In this report, we describe their thermal behavior during these tests

Sociometric approaches for managing military units and predicting of behavior of military personnel

Science.gov (United States)

Kudro, Nataliya M.; Puzikova, Svetlana M.

2017-09-01

In the Republic of Kazakhstan military service becomes attractive primarily for that category of people who have no opportunity to acquire high quality vocational or higher education, decent income by the speciality available, or those who have not yet identified themselves professionally and socially. Its a serious problem how to ensure ability of military units to execute their service duties in conditions of more and more increasing requirements for professional competences of military personnel, increased intellectualization of military service when the quality of "human material" often is not corresponding to the required standards. This problem in the national and foreign science is still being developed and has no final solutions accessible for the scientific society. This article presents an effort to offer specialists in the military administration area one of probable tools to forecast successfulness of execution of professional tasks by military units based on results of sociometric studies and algorithms of plotting Bayesian networks. Using these tools a military leader will be able to evaluate effectiveness of his managerial activity, correct mechanisms of individual and mentoring activity with regard to individual servicemen, provide an opportunity to eliminate risks of failing to fulfill professional tasks on time and failing to ensure combat readiness of entrusted military team.

Thermal invisibility based on scattering cancellation and mantle cloaking

KAUST Repository

Farhat, Mohamed; Chen, P.-Y.; Bagci, Hakan; Amra, C.; Guenneau, S.; Alù , A.

2015-01-01

We theoretically and numerically analyze thermal invisibility based on the concept of scattering cancellation and mantle cloaking. We show that a small object can be made completely invisible to heat diffusion waves, by tailoring the heat conductivity of the spherical shell enclosing the object. This means that the thermal scattering from the object is suppressed, and the heat flow outside the object and the cloak made of these spherical shells behaves as if the object is not present. Thermal invisibility may open new vistas in hiding hot spots in infrared thermography, military furtivity, and electronics heating reduction.

Thermal invisibility based on scattering cancellation and mantle cloaking

KAUST Repository

Farhat, Mohamed

2015-04-30

We theoretically and numerically analyze thermal invisibility based on the concept of scattering cancellation and mantle cloaking. We show that a small object can be made completely invisible to heat diffusion waves, by tailoring the heat conductivity of the spherical shell enclosing the object. This means that the thermal scattering from the object is suppressed, and the heat flow outside the object and the cloak made of these spherical shells behaves as if the object is not present. Thermal invisibility may open new vistas in hiding hot spots in infrared thermography, military furtivity, and electronics heating reduction.

Canadian Model of Military Leadership as a Successful Mixture of Civilian and Military Experiences

Directory of Open Access Journals (Sweden)

Piotr Malinowski

2015-06-01

Full Text Available The origins of military leadership are rooted in ancient times and its embodiment are great chieftains and commanders. However, since the moment when in organisation and management sciences the civil theories of leadership started to emerge, the military forces have incorporated their solutions to structure the assumptions of new, coherent and effective models of military leadership. A good example of such solutions is the Canadian model of military leadership, competently merging the civil theories with experience and needs of the military environment. This solution may be a perfect example of effective application of leadership theory to modify the existing national model of military leadership and construct a more efficient one.

Polymer/boron nitride nanocomposite materials for superior thermal transport performance.

Science.gov (United States)

Song, Wei-Li; Wang, Ping; Cao, Li; Anderson, Ankoma; Meziani, Mohammed J; Farr, Andrew J; Sun, Ya-Ping

2012-06-25

Boron nitride nanosheets were dispersed in polymers to give composite films with excellent thermal transport performances approaching the record values found in polymer/graphene nanocomposites. Similarly high performance at lower BN loadings was achieved by aligning the nanosheets in poly(vinyl alcohol) matrix by simple mechanical stretching (see picture). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aircrew Performance Cutting-Edge Tech: Emerging Human Performance Enhancement Technology Vision in Support of Operational Military Aviation Strategy

National Research Council Canada - National Science Library

Belland, Kris

2002-01-01

Using cutting-edge technology to create a human factors advantage in military operations will contribute to success on the battlefield of the future whether below the surface, on the surface, in the air, or in space...

Aircrew Performance Cutting-Edge Technology: Emerging Human Performance Enhancement Technology Vision in Support of Operational Military Aviation Strategy

National Research Council Canada - National Science Library

Belland, Kris M

2003-01-01

Using cutting-edge technology to create a human factors advantage in military operations will contribute to success on the battlefield of the future whether below the surface, on the surface, in the air, or in space...

Effect of thermal stress on the performance of HgCdTe/Si diodes and FPAs

International Nuclear Information System (INIS)

Zhang, Shan; Hu, Xiao-Ning

2012-01-01

As a typical hetero-epitaxial material, the HgCdTe film which directly grows on the Si substrate possesses great residual stress for the large lattice and thermal expansion mismatch. Thermal stress caused by the thermal expansion mismatch dominates the stress mechanism after growth and seriously affects the device performance. In this paper, the performance of the HgCdTe/Si material, diodes and focal plane arrays under different thermal stress condition was studied. The experimental results indicate that the performance regularly changes with the thermal stress and all the results can be duplicated and recoverable. By analyzing the changes of the energy band under different stress conditions, it was found that the stress in the HgCdTe film impacts the film's characteristics. The HgCdTe film with tensile stress exhibits higher electron mobility, while with the compressive stress, the film exhibits higher hole mobility than that of the bulk HgCdTe crystal. Finally, the theoretical analysis can explain the experimental results well. (paper)

Autogenic-feedback training as a treatment for airsickness in high-performance military aircraft: Two case studies

Science.gov (United States)

Cowings, Patricia S.; Toscano, William B.; Miller, Neal E.; Reynoso, Samuel

1994-01-01

The purpose of this paper is to present a detailed description of the physiological and performance responses of two military pilots undergoing a treatment for motion sickness. The treatment used, Autogenic-Feedback Training (AFT), is an operant conditioning procedure where subjects are taught to control several of their autonomic responses and thereby suppress their motion sickness symptoms. Two male, active duty military pilots (U.S. Navy and U. S. Marine Corps), ages 30 and 35, were each given twelve 30-minute training sessions. The primary criterion for success of training was the subject's ability to tolerate rotating chair motion sickness tests for progressively longer periods of time and at higher rotational velocities. A standardized diagnostic scale was used during motion sickness to assess changes in the subject's perceived malaise. Physiological data were obtained from one pilot during tactical maneuvers in an F-18 aircraft after completion of his training. A significant increase in tolerance to laboratory-induced motion sickness tests and a reduction in autonomic nervous system (ANS) response variability was observed for both subjects after training. Both pilots were successful in applying AFT for controlling their airsickness during subsequent qualification tests on F-18 and T-38 aircraft and were returned to active duty flight status.

Evaluation of the thermal and structural performance of straw bale construction

Science.gov (United States)

Beaudry, Kyle R.

This thesis is primarily divided into two distinct experimental programs evaluating: 1) the thermal performance and, 2) the structural performance of straw bale construction. The thermal performance chapter describes hot-box testing (based on ASTM C1363-11) of seven straw bale wall panels to obtain their apparent thermal conductivity values. All panels were constructed with stacked bales and cement-lime plaster skins on each side of the bales. Four panels were made with traditional, 2-string field bales of densities ranging from 89.5 kg/m3 - 131 kg/m3 and with the bales on-edge (fibres perpendicular to the heat flow). Three panels were made with manufactured high-density bales (291 kg/m3 - 372 kg/m3). The fibres of the manufactured bales were randomly oriented. The key conclusion of this work is that within the experimental error, there is no difference in the apparent thermal conductivity value for panels using normal density bales and manufactured high-density bales up to a density of 333 kg/m3. The structural performance chapter describes gravity and transverse load testing (based on ASTM E72-15) of non-plastered modular straw bale wall (DBW) panels to evaluate their strength capacity and failure modes. The out-of-plane flexural (OPF) tests exhibited a mean ultimate bending moment of 49.7 kNm. The axial compression (AC) tests exhibited a mean ultimate line load of 161.0 kN/m. The local flexural header beam (HP) tests exhibited an ultimate line load of 31.6 kN/m. The OPF and AC capacities of the DBW exceeded the capacities exhibited by a conventional 38 mm x 140 mm stud wall. However, the DBW's header beam strength and stiffness was inferior to conventional stud wall.

Numerical Investigation of the Thermal Management Performance of MEPCM Modules for PV Applications

Directory of Open Access Journals (Sweden)

Chao-Yang Huang

2013-08-01

Full Text Available The efficiency of photovoltaic modules decreases as the cell temperature increases. It is necessary to have an adequate thermal management mechanism for a photovoltaic module, especially when combined with a building construction system. This study aims to investigate via computational fluid dynamics simulations the heat transfer characteristics and thermal management performance of microencapsulated phase change material modules for photovoltaic applications under temporal variations of daily solar irradiation. The results show that the aspect ratio of the microencapsulated phase change material layer has significant effects on the heat transfer characteristics and the overall thermal performance of the two cases examined with different melting points (26 °C and 34 °C are approximately the same.

Accreditation status of U.S. military graduate medical education programs.

Science.gov (United States)

De Lorenzo, Robert A

2008-07-01

Military graduate medical education (GME) comprises a substantial fraction of U.S. physician training capacity. The wars in Iraq and Afghanistan have placed substantial stress on military medicine, and lay and professional press accounts have raised awareness of the effects on military GME. To date, however, objective data on military GME quality remains sparse. Determine the accreditation status of U.S. military GME programs. Additionally, military GME program data will be compared to national (U.S.) accreditation lengths. Retrospective review of Accreditation Council for Graduate Medical Education (ACGME) data. All military-sponsored core programs in specialties with at least three residencies were included. Military-affiliated but civilian-sponsored programs were excluded. The current and past cycle data were used for the study. For each specialty, the current mean accreditation length and the net change in cycle was calculated. National mean accreditation lengths by specialty for 2005 to 2006 were obtained from the ACGME. Comparison between the overall mean national and military accreditation lengths was performed with a z test. All other comparisons employed descriptive statistics. Ninety-nine military programs in 15 specialties were included in the analysis. During the study period, 1 program was newly accredited, and 6 programs had accreditation withdrawn or were closed. The mean accreditation length of the military programs was 4.0 years. The overall national mean for the same specialties is 3.5 years (p < 0.01). In previous cycles, 68% of programs had accreditation of 4 years or longer, compared to 70% in the current cycle, while 13% had accreditation of 2 years or less in the previous cycle compared to 14% in the current cycle. Ten (68%) of the military specialties had mean accreditation lengths greater than the national average, while 5 (33%) were below it. Ten (68%) specialties had stable or improving cycle lengths when compared to previous cycles

Stress Training and the New Military Environment

National Research Council Canada - National Science Library

Delahaij, R; Soeters, J. M

2006-01-01

.... This places new demands on military personnel. In combination with high levels of violence and threat, these situations will elicit acute stress reactions, which can impair performance and the ability to operate effectively...

Data Mining of the Thermal Performance of Cool-Pipes in Massive Concrete via In Situ Monitoring

OpenAIRE

Zuo, Zheng; Hu, Yu; Li, Qingbin; Zhang, Liyuan

2014-01-01

Embedded cool-pipes are very important for massive concrete because their cooling effect can effectively avoid thermal cracks. In this study, a data mining approach to analyzing the thermal performance of cool-pipes via in situ monitoring is proposed. Delicate monitoring program is applied in a high arch dam project that provides a good and mass data source. The factors and relations related to the thermal performance of cool-pipes are obtained in a built theory thermal model. The supporting ...

Three-dimensional biomimetic head model as a platform for thermal testing of protective goggles for prevention of eye injuries.

Science.gov (United States)

Friedman, Rinat; Haimy, Ayelet; Gefen, Amit; Epstein, Yoram

2018-04-22

The rate of eye injury is steadily rising during military conflicts of the century, with thermal burns being the most common type of injury to the eyes. The present study focuses on assessing the heat resistance properties of military protective goggles using three-dimensional (3D) finite element head modeling fitted with the tested protective gear. A computational thermal impact was applied onto a 3D biomimetic human head model fitted with two goggle models - sports (Type 1) and square (Type 2). The resultant temperature of the eye tissues and the thermal injury thresholds were calculated by using the modeling, hence allowing to determine the protective efficacy of the goggles objectively, in a standardized, quantitative and cost-effective manner. Both types of goggles had a dramatic protective effect on the eyes. The specific goggle geometry had no notable effect on the level of protection to the inner tissues against the thermal insult. At the skin level goggles reduced temperatures by ~64% under the impact zone, with only a mild difference (10 °C) between the goggles. Little limitations on the shape and geometry of goggles were observed and any structure of goggles can provide an adequate protection against a thermal insult (per se) to inner cranial tissues, assuming the lenses are wide and thick enough to block direct skin contact of the heat insult. It was shown that our 3D biomimetic human head model provides a practical and cost-effective tool for determining the performance level of goggles with different attributed (i.e., shapes and thermal properties). Copyright © 2018 Elsevier Ltd. All rights reserved.

Thermal and Energy Performance of Conditioned Building Due To Insulated Sloped Roof

Science.gov (United States)

Irwan, Suhandi Syiful; Ahmed, Azni Zain; Zakaria, Nor Zaini; Ibrahim, Norhati

2010-07-01

For low-rise buildings in equatorial region, the roof is exposed to solar radiation longer than other parts of the envelope. Roofs are to be designed to reject heat and moderate the thermal impact. These are determined by the design and construction of the roofing system. The pitch of roof and the properties of construction affect the heat gain into the attic and subsequently the indoor temperature of the living spaces underneath. This finally influences the thermal comfort conditions of naturally ventilated buildings and cooling load of conditioned buildings. This study investigated the effect of insulated sloping roof on thermal energy performance of the building. A whole-building thermal energy computer simulation tool, Integrated Environmental Solution (IES), was used for the modelling and analyses. A building model with dimension of 4.0 m × 4.0 m × 3.0 m was designed with insulated roof and conventional construction for other parts of the envelope. A 75 mm conductive insulation material with thermal conductivity (k-value) of 0.034 Wm-1K-1 was installed underneath the roof tiles. The building was modelled with roof pitch angles of 0° , 15°, 30°, 45°, 60° and simulated for the month of August in Malaysian climate conditions. The profile for attic temperature, indoor temperature and cooling load were downloaded and evaluated. The optimum roof pitch angle for best thermal performance and energy saving was identified. The results show the pitch angle of 0° is able to mitigate the thermal impact to provide the best thermal condition with optimum energy savings. The maximum temperature difference between insulated and non-insulted roof for attic (AtticA-B) and indoor condition (IndoorA-B) is +7.8 °C and 0.4 °C respectively with an average energy monthly savings of 3.9 %.

Effect of oral dietary supplement for chicks subjected to thermal oscillation on performance and intestinal morphometry

Directory of Open Access Journals (Sweden)

Jovanir Inês Müller Fernandes

2017-09-01

Full Text Available The aim of the study was to evaluate the efficacy of a nutritional formulation based on amino acids and vitamins supplemented in the drinking water for chicks in the first week of life subjected to thermal oscillation on performance, organ development and intestinal morphometry from 1 to 21 days. 640-male broiler chicks were distributed in a 2x2 factorial completely randomized design (with or without dietary supplementation and at comfort temperature or thermal oscillation. Chicks subjected to thermal oscillation presented worse performance (p < 0.05 than those under thermal comfort of 1 to 7, 1 to 14 and 1 to 21 days. Nutritional supplementation did not alter the performance (p < 0.05 of the birds, but resulted in a higher body weight (p < 0.05 regardless of the environmental thermal condition. At 7 days, chicks under thermal comfort had better intestinal morphometric parameters (p < 0.05, in relation to birds under thermal oscillation. In conclusion, the temperature oscillations caused negative consequences to the productive performance and the intestinal morphology of chicks for which dietary supplementation was not enough to mitigate the effects of the environmental challenge during the first week of life of the birds.

Minds "at attention": mindfulness training curbs attentional lapses in military cohorts.

Directory of Open Access Journals (Sweden)

Amishi P Jha

Full Text Available We investigated the impact of mindfulness training (MT on attentional performance lapses associated with task-unrelated thought (i.e., mind wandering. Periods of persistent and intensive demands may compromise attention and increase off-task thinking. Here, we investigated if MT may mitigate these deleterious effects and promote cognitive resilience in military cohorts enduring a high-demand interval of predeployment training. To better understand which aspects of MT programs are most beneficial, three military cohorts were examined. Two of the three groups were provided MT. One group received an 8-hour, 8-week variant of Mindfulness-based Mind Fitness Training (MMFT emphasizing engagement in training exercises (training-focused MT, n = 40, a second group received a didactic-focused variant emphasizing content regarding stress and resilience (didactic-focused MT, n = 40, and the third group served as a no-training control (NTC, n = 24. Sustained Attention to Response Task (SART performance was indexed in all military groups and a no-training civilian group (CIV, n = 45 before (T1 and after (T2 the MT course period. Attentional performance (measured by A', a sensitivity index was lower in NTC vs. CIV at T2, suggesting that performance suffers after enduring a high-demand predeployment interval relative to a similar time period of civilian life. Yet, there were significantly fewer performance lapses in the military cohorts receiving MT relative to NTC, with training-focused MT outperforming didactic-focused MT at T2. From T1 to T2, A' degraded in NTC and didactic-focused MT but remained stable in training-focused MT and CIV. In sum, while protracted periods of high-demand military training may increase attentional performance lapses, practice-focused MT programs akin to training-focused MT may bolster attentional performance more than didactic-focused programs. As such, training-focused MT programs should be further examined in cohorts

Calculated thermal performance of solar collectors based on measured weather data from 2001-2010

DEFF Research Database (Denmark)

Dragsted, Janne; Furbo, Simon; Andersen, Elsa

2015-01-01

This paper presents an investigation of the differences in modeled thermal performance of solar collectors when meteorological reference years are used as input and when mulit-year weather data is used as input. The investigation has shown that using the Danish reference year based on the period ...... with an increase in global radiation. This means that besides increasing the thermal performance with increasing the solar radiation, the utilization of the solar radiation also becomes better.......This paper presents an investigation of the differences in modeled thermal performance of solar collectors when meteorological reference years are used as input and when mulit-year weather data is used as input. The investigation has shown that using the Danish reference year based on the period...

Thermal characteristics and performance of Ag-water nanofluid: Application to natural circulation loops

International Nuclear Information System (INIS)

Koca, Halil Dogacan; Doganay, Serkan; Turgut, Alpaslan

2017-01-01

Highlights: • Thermal conductivity and viscosity of Ag-water nanofluid were measured. • Thermal performance of Ag-water nanofluid was compared with water. • Effectiveness enhanced up to 11% with 1 wt% Ag-water nanofluid. • Effectiveness of Ag-water nanofluid samples increased with inclination angle. • Ag-water nanofluid has potential to be used in flat-plate solar collectors. - Abstract: The goal of this study is to investigate the thermal conductivity, viscosity and thermal performance in a single-phase natural circulation mini loop of Ag-water nanofluid which can be a potential working fluid for natural convective flat-plate solar collectors. The silver-water nanofluid with 5 wt% concentration, which contains also polyvinylpyrrolidone (PVP) with 1.25 wt%, was purchased. Then, the sample was diluted with de-ionized water to four different concentrations of 0.25, 0.5, 0.75 and 1 wt%. Thermal conductivity and viscosity were measured by 3ω method and Brookfield rheometer, respectively. An effectiveness factor was used to define the thermal performance of Ag-water nanofluids for different inclination angles and heating powers. The results showed that nanofluid samples are thermally less conductive than the literature, at ambient temperature (23 °C). The viscosity of nanofluid decreases significantly with increasing temperature and increases with increasing concentration. Our measurements appear to be more compatible with PVP solution results available in the literature. Effectiveness is enhanced up to 11% with 1 wt% concentrated nanofluid compared to de-ionized water and the effectiveness of the mini loop indicates an enhancement with increase in inclination angle and particle concentration at whole applied power. According to obtained results, it is concluded that Ag-water nanofluid has a promising potential to be used in natural convective flat-plate solar collector.

Performance of thermally-chargeable supercapacitors in different solvents.

Science.gov (United States)

Lim, Hyuck; Zhao, Cang; Qiao, Yu

2014-07-07

The influence of solvent on the temperature sensitivity of the electrode potential of thermally-chargeable supercapacitors (TCSs) is investigated. For large electrodes, the output voltage is positively correlated with the dielectric constant of solvent. When nanoporous carbon electrodes are used, different characteristics of system performance are observed, suggesting that possible size effects must be taken into consideration when the solvent molecules and solvated ions are confined in a nanoenvironment.

A Comparison of Military and Law Enforcement Body Armour

Science.gov (United States)

Pope, Rodney

2018-01-01

Law-enforcement officers increasingly wear body armour for protection; wearing body armour is common practice in military populations. Law-enforcement and military occupational demands are vastly different and military-styled body armour may not be suitable for law-enforcement. This study investigated differences between selected military body armour (MBA: 6.4 kg) and law-enforcement body armour (LEBA: 2.1 kg) in impacts on postural sway, vertical jump, agility, a functional movement screen (FMS), task simulations (vehicle exit; victim recovery), and subjective measures. Ten volunteer police officers (six females, four males) were randomly allocated to one of the designs on each of two days. Body armour type did not significantly affect postural sway, vertical jump, vehicle exit and 5 m sprint times, or victim recovery times. Both armour types increased sway velocity and sway-path length in the final five seconds compared to the first 5 s of a balance task. The MBA was associated with significantly slower times to complete the agility task, poorer FMS total scores, and poorer subjective ratings of performance and comfort. The LEBA was perceived as more comfortable and received more positive performance ratings during the agility test and task simulations. The impacts of MBA and LEBA differed significantly and they should not be considered interchangeable. PMID:29443905

A Comparison of Military and Law Enforcement Body Armour.

Science.gov (United States)

Orr, Robin; Schram, Ben; Pope, Rodney

2018-02-14

Law-enforcement officers increasingly wear body armour for protection; wearing body armour is common practice in military populations. Law-enforcement and military occupational demands are vastly different and military-styled body armour may not be suitable for law-enforcement. This study investigated differences between selected military body armour (MBA: 6.4 kg) and law-enforcement body armour (LEBA: 2.1 kg) in impacts on postural sway, vertical jump, agility, a functional movement screen (FMS), task simulations (vehicle exit; victim recovery), and subjective measures. Ten volunteer police officers (six females, four males) were randomly allocated to one of the designs on each of two days. Body armour type did not significantly affect postural sway, vertical jump, vehicle exit and 5 m sprint times, or victim recovery times. Both armour types increased sway velocity and sway-path length in the final five seconds compared to the first 5 s of a balance task. The MBA was associated with significantly slower times to complete the agility task, poorer FMS total scores, and poorer subjective ratings of performance and comfort. The LEBA was perceived as more comfortable and received more positive performance ratings during the agility test and task simulations. The impacts of MBA and LEBA differed significantly and they should not be considered interchangeable.

A Comparison of Military and Law Enforcement Body Armour

Directory of Open Access Journals (Sweden)

Robin Orr

2018-02-01

Full Text Available Law-enforcement officers increasingly wear body armour for protection; wearing body armour is common practice in military populations. Law-enforcement and military occupational demands are vastly different and military-styled body armour may not be suitable for law-enforcement. This study investigated differences between selected military body armour (MBA: 6.4 kg and law-enforcement body armour (LEBA: 2.1 kg in impacts on postural sway, vertical jump, agility, a functional movement screen (FMS, task simulations (vehicle exit; victim recovery, and subjective measures. Ten volunteer police officers (six females, four males were randomly allocated to one of the designs on each of two days. Body armour type did not significantly affect postural sway, vertical jump, vehicle exit and 5 m sprint times, or victim recovery times. Both armour types increased sway velocity and sway-path length in the final five seconds compared to the first 5 s of a balance task. The MBA was associated with significantly slower times to complete the agility task, poorer FMS total scores, and poorer subjective ratings of performance and comfort. The LEBA was perceived as more comfortable and received more positive performance ratings during the agility test and task simulations. The impacts of MBA and LEBA differed significantly and they should not be considered interchangeable.

Performance model and thermal comparison of different alternatives for the Fresnel single-tube receiver

International Nuclear Information System (INIS)

Montes, María J.; Barbero, Rubén; Abbas, Rubén; Rovira, Antonio

2016-01-01

Highlights: • A thermal model for a single-tube Fresnel receiver has been developed. • A comparative analysis based on different design parameters, has been carried out. • A comparative analysis based on different working fluids, has been carried out. • The receiver thermal performance is characterized by energy and exergy efficiencies. - Abstract: Although most of recent commercial Solar Thermal Power Plants (STPP) installed worldwide are parabolic trough plants, it seems that Linear Fresnel Collectors (LFC) are becoming an attractive option to generate electricity from solar radiation. Contrary to parabolic trough collectors, the design of LFC receivers has many degrees of freedom, and two basic designs can be found in the literature: single-tube and multi-tube design. This article studies the single-tube design, for which a thermal model has been developed. This model has been thought to be accurate enough to characterize the heat transfer in a non-elementary geometry and flexible enough to support changes of the characteristic parameters in the receiver design. The thermal model proposed is based on a two-dimensional, steady-state energy balance, in the receiver cross section and along its length. One of the features of the model is the characterization of the convective and radiative heat transfer in the receiver cavity, as it is not an elementary geometry. Another feature is the possibility of studying the receiver performance with different working fluids, both single-phase or two-phase. At last, the receiver performance has been characterized by means of the energy and exergy efficiency. Both variables are important for a complete receiver thermal analysis, as will be shown in the paper. The model has been first applied to the comparative study of the thermal performance of LFC receivers based on the value of some parameters: selective coating emissivity in the tube and inlet fluid thermal properties, for the case of using water/steam. As a second

Thermal performance test of the hot gas ducts of HENDEL

International Nuclear Information System (INIS)

Hishida, M.; Kunitomi, K.; Ioka, I.; Umenishi, K.; Tanaka, T.; Shimomura, H.; Sanokawa, K.

1984-01-01

A hot gas duct provided with internal thermal insulation is to be used for high-temperature gas-cooled reactors (HTGR). This type of hot gas duct has not been used so far in industrial facilities, and only a couple of tests on such a large-scale model of a hot gas duct have been conducted. The present report deals with the results of the thermal performance of the single tube type hot gas ducts which are installed as parts of a helium engineering demonstration loop (HENDEL). Uniform temperature and heat flux distribution at the surface of the duct were observed, the experimental correlations being obtained for the effective thermal conductivity of the internal thermal insulation layer. The measured temperature distribution of the pressure tube was in good agreement with the calculation by a TRUMP heat transfer computer code. The temperature distribution of the inner tube of the co-axial hot gas duct was evaluated and no hot spot was detected. These results would be very valuable for the design and development of HTGR. (orig.)

Experimental investigation of a PCM-HP heat sink on its thermal performance and anti-thermal-shock capacity for high-power LEDs

International Nuclear Information System (INIS)

Wu, Yuxuan; Tang, Yong; Li, Zongtao; Ding, Xinrui; Yuan, Wei; Zhao, Xuezhi; Yu, Binhai

2016-01-01

Highlights: • A phase-change material (PCM) base heat pipe heat sink (PCM-HP heat sink) is designed. • The PCM-HP heat sink can significantly lower the LED heating rate and temperature. • The PCM-HP heat sink achieves a best anti-thermal-shock capacity in LED cyclic working modes. - Abstract: High-power LEDs demonstrate a number of benefits compared with conventional incandescent lamps and fluorescent lamps, including a longer lifetime, higher brightness and lower power consumption. However, owing to their severe high heat flux, it is difficult to develop effective thermal management of high-power LEDs, especially under cyclic working modes, which cause serious periodic thermal stress and limit further development. Focusing on the above problem, this paper designed a phase-change material (PCM) base heat pipe heat sink (PCM-HP heat sink) that consists of a PCM base, adapter plate, heat pipe and finned radiator. Different parameters, such as three types of interior materials to fill the heat sink, three LED power inputs and eight LED cyclic working modes, were separately studied to investigate the thermal performance and anti-thermal-shock capacity of the PCM-HP heat sink. The results show that the PCM-HP heat sink possesses remarkable thermal performance owing to the reduction of the LED heating rate and peak temperature. More importantly, an excellent anti-thermal-shock capacity of the PCM-HP heat sink is also demonstrated when applied in LED cyclic working modes, and this capacity demonstrates the best range.

Helmet-Induced Occipital Neuralgia in a Military Aviator.

Science.gov (United States)

Chalela, Julio A

2018-04-01

Headaches among military personnel are very common and headgear wear is a frequently identified culprit. Helmet wear may cause migrainous headaches, external compression headache, other primary cranial neuralgias, and occipital neuralgia. The clinical features and the response to treatment allow distinction between the different types of headaches. Headaches among aviators are particularly concerning as they may act as distractors while flying and the treatment options are often incompatible with flying status. A 24-yr-old door gunner presented with suboccipital pain associated with the wear of his helmet. He described the pain as a paroxysmal stabbing sensation coming in waves. The physical exam and history supported the diagnosis of primary occipital neuralgia. Systemic pharmacological options were discussed with the soldier, but rejected due to his need to remain in flying status. An occipital nerve block was performed with good clinical results, supporting the diagnosis of occipital neuralgia and allowing him to continue as mission qualified. Occipital neuralgia can be induced by helmet wear in military personnel. Occipital nerve block can be performed in the deployed setting, allowing the service member to remain mission capable and sparing him/her from systemic side effects.Chalela JA. Helmet-induced occipital neuralgia in a military aviator. Aerosp Med Hum Perform. 2018; 89(4):409-410.

Design, modeling and performance analysis of dual channel semitransparent photovoltaic thermal hybrid module in the cold environment

International Nuclear Information System (INIS)

Singh, Sonveer; Agrawal, Sanjay; Avasthi, D.V.

2016-01-01

Highlights: • Thermal modeling of novel dual channel semitransparent PVT hybrid module. • Exergy and carbon credit analysis has been performed. • Annual performance has been evaluated for Srinagar (India). • There are improvements in results for case-I as compared to case-II. - Abstract: In this work, thermal modeling and performance analysis of the dual channel semitransparent photovoltaic thermal (DCSPVT) module has been carried out. For extracting heat associated with the lower and upper surface of the solar cell, two channels have been proposed; (i) one is above the solar cell called upper channel and (ii) second is below the solar cell called lower channel. Firstly, thermal modeling of DCSPVT module has been developed. After that, performance analysis of the above system has been carried out for Srinagar, Indian climatic condition. Performance in terms of electrical gain (EG), thermal gain (TG), overall exergy gain (OEG), overall thermal gain (OTG), electrical efficiency (EE) and overall exergy efficiency (OEE) of the DCSPVT module (case-I) have been compared with single channel semitransparent photovoltaic thermal (SCSPVT) hybrid module (case-II). The average improvement in EG, TG, OEG, OTG of the case-I have been observed by 71.51%, 34.57%, 5.78% and 35.41% respectively as compared to case-II.

China's Military Potential

National Research Council Canada - National Science Library

Wortzel, Larry

1998-01-01

The People's Republic of China (PRC) is seen by many as an economic powerhouse with the world's largest standing military that has the potential to translate economic power into the military sphere...

Obesity and the US Military Family

Science.gov (United States)

Tanofsky-Kraff, Marian; Sbrocco, Tracy; Theim, Kelly R.; Cohen, L. Adelyn; Mackey, Eleanor R.; Stice, Eric; Henderson, Jennifer L.; McCreight, Sarah J.; Bryant, Edny J.; Stephens, Mark B.

2014-01-01

Objective This review discusses the current knowledge and future directions regarding obesity within the US military family (i.e., active-duty servicemembers, as well as military spouses, children, retirees, and veterans). The increasing rates of overweight and obesity within the US military adversely impact military readiness, limit recruitment, and place a significant financial burden on the Department of Defense. Design and Methods The following topics are reviewed: 1) The prevalence of and the financial, physical, and psychological costs associated with overweight in military communities; 2) military weight regulations, and challenges faced by the military family related to overweight and disordered eating; 3) the continued need for rigorous program evaluations and new intervention development. Results Overweight and its associated sequelae impact the entire military family. Military families share many similarities with their civilian counterparts, but they face unique challenges (e.g., stress related to deployments and relocations). Although the military has weight management resources, there is an urgent need for rigorous program evaluation and the development of enhanced obesity prevention programs across the lifespan of the military family–several of which are proposed herein. Conclusions Interdisciplinary and collaborative research efforts and team-based interventions will continue to inform understanding of obesity treatment and prevention within military and civilian populations. PMID:23836452

Thermal performance monitoring and assessment in Dukovany nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Madron, F. [Chemplant Technology s.r.o., Hrncirska 4, 400 01 Usti nad Labem (Czech Republic); Papuga, J. [CEZ a.s., JE Dukovany, 675 50 Dukovany (Czech Republic); Pliska, J. [I and C ENERGO a.s., Prazska 684, 674 01 Trebic (Czech Republic)

2006-07-01

Competition in the European electricity market forces generators to achieve - in compliance with safety and environmental standards - efficiency of production as high as possible. This efficiency or heat rate is an important indicator of both the condition of the plant equipment and the quality of plant operation. Similar thermal performance indicators can also be calculated for components of the plant equipment such as heat exchangers. However, it is not easy to quantify these indicators with sufficient precision so that the results can be used for conduct of plant operation in near-real time and for predictive maintenance. This paper describes a present state of the system monitoring and evaluating thermal performance of the reactor units in Dukovany Nuclear Power Plant. The system provides information on actual and desirable (should-be) values of thermal performance indicators for control room operators, performance engineers and maintenance planners. The system is designed to monitor steady states and has two main functions: data validation and process simulation. Data validation is based on data reconciliation methodology and carried out with Recon software by Chemplant Technology. A detailed model of the secondary side for mass and heat balancing has been made up by means of the Recon's graphical editor; now it contains roughly 300 flows and employs data of about 200 measurements. Main advantages of the data reconciliation are: - reconciled data are consistent with the model, - reconciled data are more precise than data directly measured with consequence that the thermal power of steam generators is determined with substantially lower uncertainty than before - data reconciliation represents a solid basis for detection and identification of data corrupted by gross errors. Simulation is performed with a different analytical model of plant components configured into secondary side. The model has been developed by I and C Energo. Main purposes of simulation

High-performance flat-panel solar thermoelectric generators with high thermal concentration

Science.gov (United States)

Kraemer, Daniel; Poudel, Bed; Feng, Hsien-Ping; Caylor, J. Christopher; Yu, Bo; Yan, Xiao; Ma, Yi; Wang, Xiaowei; Wang, Dezhi; Muto, Andrew; McEnaney, Kenneth; Chiesa, Matteo; Ren, Zhifeng; Chen, Gang

2011-07-01

The conversion of sunlight into electricity has been dominated by photovoltaic and solar thermal power generation. Photovoltaic cells are deployed widely, mostly as flat panels, whereas solar thermal electricity generation relying on optical concentrators and mechanical heat engines is only seen in large-scale power plants. Here we demonstrate a promising flat-panel solar thermal to electric power conversion technology based on the Seebeck effect and high thermal concentration, thus enabling wider applications. The developed solar thermoelectric generators (STEGs) achieved a peak efficiency of 4.6% under AM1.5G (1 kW m-2) conditions. The efficiency is 7-8 times higher than the previously reported best value for a flat-panel STEG, and is enabled by the use of high-performance nanostructured thermoelectric materials and spectrally-selective solar absorbers in an innovative design that exploits high thermal concentration in an evacuated environment. Our work opens up a promising new approach which has the potential to achieve cost-effective conversion of solar energy into electricity.

High-performance flat-panel solar thermoelectric generators with high thermal concentration.

Science.gov (United States)

Kraemer, Daniel; Poudel, Bed; Feng, Hsien-Ping; Caylor, J Christopher; Yu, Bo; Yan, Xiao; Ma, Yi; Wang, Xiaowei; Wang, Dezhi; Muto, Andrew; McEnaney, Kenneth; Chiesa, Matteo; Ren, Zhifeng; Chen, Gang

2011-05-01

The conversion of sunlight into electricity has been dominated by photovoltaic and solar thermal power generation. Photovoltaic cells are deployed widely, mostly as flat panels, whereas solar thermal electricity generation relying on optical concentrators and mechanical heat engines is only seen in large-scale power plants. Here we demonstrate a promising flat-panel solar thermal to electric power conversion technology based on the Seebeck effect and high thermal concentration, thus enabling wider applications. The developed solar thermoelectric generators (STEGs) achieved a peak efficiency of 4.6% under AM1.5G (1 kW m(-2)) conditions. The efficiency is 7-8 times higher than the previously reported best value for a flat-panel STEG, and is enabled by the use of high-performance nanostructured thermoelectric materials and spectrally-selective solar absorbers in an innovative design that exploits high thermal concentration in an evacuated environment. Our work opens up a promising new approach which has the potential to achieve cost-effective conversion of solar energy into electricity. © 2011 Macmillan Publishers Limited. All rights reserved

The Reasons for Living Scale-Military Version: Assessing Protective Factors Against Suicide in a Military Sample.

Science.gov (United States)

Deutsch, Anne-Marie; Lande, R Gregory

2017-07-01

Military suicide rates have been rising over the past decade and continue to challenge military treatment facilities. Assessing suicide risk and improving treatments are a large part of the mission for clinicians who work with uniformed service members. This study attempts to expand the toolkit of military suicide prevention by focusing on protective factors over risk factors. In 1983, Marsha Linehan published a checklist called the Reasons for Living Scale, which asked subjects to check the reasons they choose to continue living, rather than choosing suicide. The authors of this article hypothesized that military service members may have different or additional reasons to live which may relate to their military service. They created a new version of Linehan's inventory by adding protective factors related to military life. The purpose of these additions was to make the inventory more acceptable and relevant to the military population, as well as to identify whether these items constitute a separate subscale as distinguished from previously identified factors. A commonly used assessment tool, the Reasons for Living Inventory (RFL) designed by Marsha Linehan, was expanded to offer items geared to the military population. The RFL presents users with a list of items which may be reasons to not commit suicide (e.g., "I have a responsibility and commitment to my family"). The authors used focus groups of staff and patients in a military psychiatric partial hospitalization program to identify military-centric reasons to live. This process yielded 20 distinct items which were added to Linehan's original list of 48. This expanded list became the Reasons for Living-Military Version. A sample of 200 patients in the military partial hospitalization program completed the inventory at time of or close to admission. This study was approved by the Institutional Review Board at Walter Reed National Military Center for adhering to ethical principles related to pursuing research

Methodology for thermal hydraulic conceptual design and performance analysis of KALIMER core

International Nuclear Information System (INIS)

Young-Gyun Kim; Won-Seok Kim; Young-Jin Kim; Chang-Kue Park

2000-01-01

This paper summarizes the methodology for thermal hydraulic conceptual design and performance analysis which is used for KALIMER core, especially the preliminary methodology for flow grouping and peak pin temperature calculation in detail. And the major technical results of the conceptual design for the KALIMER 98.03 core was shown and compared with those of KALIMER 97.07 design core. The KALIMER 98.03 design core is proved to be more optimized compared to the 97.07 design core. The number of flow groups are reduced from 16 to 11, and the equalized peak cladding midwall temperature from 654 deg. C to 628 deg. C. It was achieved from the nuclear and thermal hydraulic design optimization study, i.e. core power flattening and increase of radial blanket power fraction. Coolant flow distribution to the assemblies and core coolant/component temperatures should be determined in core thermal hydraulic analysis. Sodium flow is distributed to core assemblies with the overall goal of equalizing the peak cladding midwall temperatures for the peak temperature pin of each bundle, thus pin cladding damage accumulation and pin reliability. The flow grouping and the peak pin temperature calculation for the preliminary conceptual design is performed with the modules ORFCE-F60 and ORFCE-T60 respectively. The basic subchannel analysis will be performed with the SLTHEN code, and the detailed subchannel analysis will be done with the MATRA-LMR code which is under development for the K-Core system. This methodology was proved practical to KALIMER core thermal hydraulic design from the related benchmark calculation studies, and it is used to KALIMER core thermal hydraulic conceptual design. (author)

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

In-situ long-term thermal performance of impermeably face polyiso foam boards

Energy Technology Data Exchange (ETDEWEB)

Mukhopadhyaya, Phalguni; Normandin, Nicole; Van Reenen, David; Lackey, John [National Research Council Canada, Institute for Reserch in Construction, Ottawa, (Canada); Drouin, Michel [Consultant, Dorion, (Canada)

2010-07-01

Closed-cell polyisocyanurate (polyiso) foam insulation products are widely used in building envelope constructions as they have one of the highest R-values per unit thickness among the insulations used in the construction industry. The introduction of impermeable facers on the surface of polyiso rigid board is aimed at enhancing the long-term thermal resistance (LTTR) properties of the foam. This paper evaluated the thermal performance of impermeably faced polyiso boards after more than six years of field exposure. Boards were installed and instrumented at NRC-IRC's field test facility. Field monitoring was performed on a regular basis for six years of exposure until 2008. Then, nine specimens were cut from the boards which were removed from the test hut to evaluate their thermal characteristic using a heat flow meter apparatus. It was found that the impermeably faced polyiso foam insulation boards aged significantly.

Experiment study on thermal mixing performance of HTR-PM reactor outlet

Energy Technology Data Exchange (ETDEWEB)

Zhou, Yangping, E-mail: zhouyp@mail.tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Collaborative Innovation Center of Advanced Nuclear Energy Technology, the Key Laboratory of Advanced Reactor Engineering and Safety, Ministry of Education, Tsinghua University, Beijing 100084 (China); Hao, Pengfei [School of Aerospace, Tsinghua University, Beijing 100084 (China); Li, Fu; Shi, Lei [Institute of Nuclear and New Energy Technology, Collaborative Innovation Center of Advanced Nuclear Energy Technology, the Key Laboratory of Advanced Reactor Engineering and Safety, Ministry of Education, Tsinghua University, Beijing 100084 (China); He, Feng [School of Aerospace, Tsinghua University, Beijing 100084 (China); Dong, Yujie; Zhang, Zuoyi [Institute of Nuclear and New Energy Technology, Collaborative Innovation Center of Advanced Nuclear Energy Technology, the Key Laboratory of Advanced Reactor Engineering and Safety, Ministry of Education, Tsinghua University, Beijing 100084 (China)

2016-09-15

A model experiment is proposed to investigate the thermal mixing performance of HTR-PM reactor outlet. The design of the test facility is introduced, which is set at a scale of 1:2.5 comparing with the design of thermal mixing structure at HTR-PM reactor outlet. The test facility using air as its flow media includes inlet pipe system, electric heaters, main mixing structure, hot gas duct, exhaust pipe system and I&C system. Experiments are conducted on the test facility and the values of thermal-fluid parameters are collected and analyzed, which include the temperature, pressure and velocity of the flow as well as the temperature of the tube wall. The analysis results show the mixing efficiency of the test facility is higher than that required by the steam generator of HTR-PM, which indicates that the thermal mixing structure of HTR-PM fulfills its design requirement.

Thermal Fatigue Evaluation of Pb-Free Solder Joints: Results, Lessons Learned, and Future Trends

Science.gov (United States)

Coyle, Richard J.; Sweatman, Keith; Arfaei, Babak

2015-09-01

Thermal fatigue is a major source of failure of solder joints in surface mount electronic components and it is critically important in high reliability applications such as telecommunication, military, and aeronautics. The electronic packaging industry has seen an increase in the number of Pb-free solder alloy choices beyond the common near-eutectic Sn-Ag-Cu alloys first established as replacements for eutectic SnPb. This paper discusses the results from Pb-free solder joint reliability programs sponsored by two industry consortia. The characteristic life in accelerated thermal cycling is reported for 12 different Pb-free solder alloys and a SnPb control in 9 different accelerated thermal cycling test profiles in terms of the effects of component type, accelerated thermal cycling profile and dwell time. Microstructural analysis on assembled and failed samples was performed to investigate the effect of initial microstructure and its evolution during accelerated thermal cycling test. A significant finding from the study is that the beneficial effect of Ag on accelerated thermal cycling reliability (measured by characteristic lifetime) diminishes as the severity of the accelerated thermal cycling, defined by greater ΔT, higher peak temperature, and longer dwell time increases. The results also indicate that all the Pb-free solders are more reliable in accelerated thermal cycling than the SnPb alloy they have replaced. Suggestions are made for future work, particularly with respect to the continued evolution of alloy development for emerging application requirements and the value of using advanced analytical methods to provide a better understanding of the effect of microstructure and its evolution on accelerated thermal cycling performance.

Design and Performance Optimizations of Advanced Erosion-Resistant Low Conductivity Thermal Barrier Coatings for Rotorcraft Engines

Science.gov (United States)

Zhu, Dongming; Miller, Robert A.; Kuczmarski, Maria A.

2012-01-01

Thermal barrier coatings will be more aggressively designed to protect gas turbine engine hot-section components in order to meet future rotorcraft engine higher fuel efficiency and lower emission goals. For thermal barrier coatings designed for rotorcraft turbine airfoil applications, further improved erosion and impact resistance are crucial for engine performance and durability, because the rotorcraft are often operated in the most severe sand erosive environments. Advanced low thermal conductivity and erosion-resistant thermal barrier coatings are being developed, with the current emphasis being placed on thermal barrier coating toughness improvements using multicomponent alloying and processing optimization approaches. The performance of the advanced thermal barrier coatings has been evaluated in a high temperature erosion burner rig and a laser heat-flux rig to simulate engine erosion and thermal gradient environments. The results have shown that the coating composition and architecture optimizations can effectively improve the erosion and impact resistance of the coating systems, while maintaining low thermal conductivity and cyclic oxidation durability

BUILDING HIGH PERFORMANCE STRATEGY OF MILITARY EXPENDITURES: THE UTILITY FUNCTION IN THE MIDDLE OF DEFENCE BUDGETING

Directory of Open Access Journals (Sweden)

MARITANA SEDYSHEVA

2011-01-01

Full Text Available The present paper proposes tasks and methods which can be used in process of discovering the most expedient variants of the perspective and effective strategy development process of the defence spending in the Republic of Estonia.The author offers a part of strategy model named “Financial Perspective” as one of the improvement tools for the system of planning military expenditures and effective utilization of budgetary funds. The Balanced Scorecard application by using the “utility function” will allow the Estonian Defence Forces to overcome important barriers to strategy implementation by interrelation of military planning and budgeting processes. The Balanced Scorecard might be used as a very strong practical application. It will improve the calculations of long-term perspective plans and the development of the military budgetary policy by taking into account the features of national defence expenses.

Characterization of systems for external insulation and retrofitting with emphasis on the thermal performance

DEFF Research Database (Denmark)

Rudbeck, Claus; Rose, Jørgen

1999-01-01

During the last decade retrofitting of buildings has received increased attention not only in northern Europe but throughout the world. Retrofitting of buildings is usually performed to solve one or more of the following problems: poor indoor climate, excessive heat losses, insufficient durability...... a building designer with such a choice, key parameters for insulation systems are described in a uniform manner stating their performance with regards to aesthetics, heat transfer, moisture, durability, fire and economy. Parameters given for the total insulation capability enable the building designer...... to include the effect of thermal bridges by performing simple calculations, a task which normally requires the use of numerical models. The results show that thermal bridges in external insulation systems may decrease their thermal resistance by more than 25%.Key parameters was calculated by the use...

Thermal performance of a Stirling engine powered by a solar simulator

International Nuclear Information System (INIS)

Aksoy, Fatih; Karabulut, Halit; Çınar, Can; Solmaz, Hamit; Özgören, Yasar Önder; Uyumaz, Ahmet

2015-01-01

In this study, the performance of a beta type Stirling engine which works at relatively lower temperatures was investigated using 400 W and 1000 W halogen lamps as a heat source and helium as the working fluid. The working fluid was charged into the engine block and the pressure of the working fluid was ranged from 1 to 5 bars with 1 bar increments. The halogen lamps were placed into a cavity adjacent to the hot end of the displacer cylinder, which is made of aluminum alloy. In the experiments conducted with 400 W halogen lamp, the temperature of the cavity was 623 ± 10 K. The power, torque and thermal efficiency of the engine were determined to be 37.08 W, 1.68 Nm and 9.27%, at 5 bar charge pressure. For the 1000 W halogen lamp, the temperature of the cavity was determined to be 873 ± 10 K. The power, torque and thermal efficiency of the engine were determined to be 127.17 W, 3.4 Nm and 12.85%, at the same charge pressure. The experimental thermal efficiencies of the engine were also compared with thermodynamic nodal analysis. - Highlights: • The performance of a beta type Stirling engine was investigated. • 400 and 1000 W halogen lamps were used as a solar simulator in the experiments. • Cavity temperature was measured 623 and 873 K for 400 and 1000 W lamps. • 1000 W halogen lamp provided better engine performance and thermal efficiency. • Experimental results of efficiency were compared with nodal analysis results

Thermal performance and heat transport in aquifer thermal energy storage

NARCIS (Netherlands)

Sommer, W.T.; Doornenbal, P.J.; Drijver, B.C.; Gaans, van P.F.M.; Leusbrock, I.; Grotenhuis, J.T.C.; Rijnaarts, H.H.M.

2014-01-01

Aquifer thermal energy storage (ATES) is used for seasonal storage of large quantities of thermal energy. Due to the increasing demand for sustainable energy, the number of ATES systems has increased rapidly, which has raised questions on the effect of ATES systems on their surroundings as well as

Data Mining of the Thermal Performance of Cool-Pipes in Massive Concrete via In Situ Monitoring

Directory of Open Access Journals (Sweden)

Zheng Zuo

2014-01-01

Full Text Available Embedded cool-pipes are very important for massive concrete because their cooling effect can effectively avoid thermal cracks. In this study, a data mining approach to analyzing the thermal performance of cool-pipes via in situ monitoring is proposed. Delicate monitoring program is applied in a high arch dam project that provides a good and mass data source. The factors and relations related to the thermal performance of cool-pipes are obtained in a built theory thermal model. The supporting vector machine (SVM technology is applied to mine the data. The thermal performances of iron pipes and high-density polyethylene (HDPE pipes are compared. The data mining result shows that iron pipe has a better heat removal performance when flow rate is lower than 50 L/min. It has revealed that a turning flow rate exists for iron pipe which is 80 L/min. The prediction and classification results obtained from the data mining model agree well with the monitored data, which illustrates the validness of the approach.

Military Internal Medicine Resident Decision to Apply to Fellowship and Extend Military Commitment.

Science.gov (United States)

Barsoumian, Alice E; Hartzell, Joshua D; Bonura, Erin M; Ressner, Roseanne A; Whitman, Timothy J; Yun, Heather C

2018-02-06

Nationally, the number of internal medicine physicians practicing in primary care has decreased amidst increasing interest in hospitalist medicine. Current priorities in the Military Health System include access to primary care and retention of trained personnel. Recently, we have conducted a study of military internal medicine residents' decision to enter infectious disease. As part of our larger effort, we saw an opportunity to characterize factors impacting decision making of internal medicine residents' desire to apply for subspecialty training and to extend active duty service obligations. Questions were developed after discussion with various military graduate medical education and internal medicine leaders, underwent external review, and were added to a larger question set. The survey link was distributed electronically to all U.S. military affiliated residencies' graduating internal medicine residents in December 2016-January 2017. Data were analyzed by decision to apply to fellowship and decision to extend military obligation using Fisher's exact test or Pearon's chi-square test. Sixty-eight residents from 10 of 11 military residency programs responded, for a response rate of 51%. The majority (62%) applied to fellowship to start after residency completion. Reasons cited for applying to fellowship included wanting to become a specialist as soon as possible (74%), wishing to avoid being a general internist (57%), and because they are unable to practice as a hospitalist in the military (52%). Fellowship applicants were more likely to plan to extend their military obligation than non-applicants, as did those with longer duration of military commitments. No other factors, including Uniformed Services University attendance or participation in undergraduate military experiences, were found to impact plan to extend active duty service commitment. The majority of graduating internal medicine residents apply for fellowship and report a desire to avoid being a

A numerical and experimental investigation of the thermal control performance of a spaceborne compressor assembly

Science.gov (United States)

Oh, Hyun-Ung; Lee, Min-Kyu; Shin, Somin; Hong, Joo-Sung

2011-09-01

Spaceborne pulse tube type cryocoolers are widely used for providing cryogenic temperatures for sensitive infrared, gamma-ray and X-ray detectors. Thermal control for the compressor of the cryocooler is one of the important technologies for the cooling performance, mission life time, and jitter stability of the cooler. The thermal design of the compressor assembly proposed in this study is basically composed of a heat pipe, a radiator, and a heater. In the present work, a method for heat pipe implementation is proposed and investigated to ensure the jitter stability of the compressor under the condition that one heat pipe is not working. An optimal design of the radiator that uses ribs for effective use by minimizing the temperature gradient on the radiator and reducing its weight is introduced. The effectiveness of the thermal design of the compressor assembly is demonstrated by on-orbit thermal analysis using the correlated thermal model obtained from the thermal balance test that is performed under a space simulating environment.

MILITARY CONSTRUCTION: Kaiserslautern Military Community Center Project Continues to Experience Problems

National Research Council Canada - National Science Library

Kutz, Gregory D; Causseaux, Bruce A; Dorn, Terrell G

2008-01-01

The Kaiserslautern Military Community Center (KMCC) is one of many projects initiated at Ramstein Air Base to upgrade capabilities of the base as a result of the consolidation of military bases in Europe...

Performance maps for the control of thermal energy storage

DEFF Research Database (Denmark)

Finck, Christian; Li, Rongling; Zeiler, Wim

2017-01-01

Predictive control in building energy systems requires the integration of the building, building system, and component dynamics. The prediction accuracy of these dynamics is crucial for practical applications. This paper introduces performance maps for the control of water tanks, phase change mat...... material tanks, and thermochemical material tanks. The results show that these performance maps can fully account for the dynamics of thermal energy storage tanks.......Predictive control in building energy systems requires the integration of the building, building system, and component dynamics. The prediction accuracy of these dynamics is crucial for practical applications. This paper introduces performance maps for the control of water tanks, phase change...

A New Model for Optimal Mechanical and Thermal Performance of Cement-Based Partition Wall.

Science.gov (United States)

Huang, Shiping; Hu, Mengyu; Huang, Yonghui; Cui, Nannan; Wang, Weifeng

2018-04-17

The prefabricated cement-based partition wall has been widely used in assembled buildings because of its high manufacturing efficiency, high-quality surface, and simple and convenient construction process. In this paper, a general porous partition wall that is made from cement-based materials was proposed to meet the optimal mechanical and thermal performance during transportation, construction and its service life. The porosity of the proposed partition wall is formed by elliptic-cylinder-type cavities. The finite element method was used to investigate the mechanical and thermal behaviour, which shows that the proposed model has distinct advantages over the current partition wall that is used in the building industry. It is found that, by controlling the eccentricity of the elliptic-cylinder cavities, the proposed wall stiffness can be adjusted to respond to the imposed loads and to improve the thermal performance, which can be used for the optimum design. Finally, design guidance is provided to obtain the optimal mechanical and thermal performance. The proposed model could be used as a promising candidate for partition wall in the building industry.

A New Model for Optimal Mechanical and Thermal Performance of Cement-Based Partition Wall

Directory of Open Access Journals (Sweden)

Shiping Huang

2018-04-01

Full Text Available The prefabricated cement-based partition wall has been widely used in assembled buildings because of its high manufacturing efficiency, high-quality surface, and simple and convenient construction process. In this paper, a general porous partition wall that is made from cement-based materials was proposed to meet the optimal mechanical and thermal performance during transportation, construction and its service life. The porosity of the proposed partition wall is formed by elliptic-cylinder-type cavities. The finite element method was used to investigate the mechanical and thermal behaviour, which shows that the proposed model has distinct advantages over the current partition wall that is used in the building industry. It is found that, by controlling the eccentricity of the elliptic-cylinder cavities, the proposed wall stiffness can be adjusted to respond to the imposed loads and to improve the thermal performance, which can be used for the optimum design. Finally, design guidance is provided to obtain the optimal mechanical and thermal performance. The proposed model could be used as a promising candidate for partition wall in the building industry.

Military Construction, Military Quality of Life and Veterans Affairs: FY2007 Appropriations

National Research Council Canada - National Science Library

Else, Daniel H; Scott, Christine; Panangala, Sidath V

2007-01-01

... construction, military housing allowances, military installation maintenance and operation, the Department of Veterans Affairs, and other veteran-related agencies, rested in the House Committee...

Performance of cardiopulmonary resuscitation during prolonged basic life support in military medical university students: A manikin study

Science.gov (United States)

Wang, Juan; Zhuo, Chao-nan; Zhang, Lei; Gong, Yu-shun; Yin, Chang-lin; Li, Yong-qin

2015-01-01

BACKGROUND: The quality of chest compressions can be significantly improved after training of rescuers according to the latest national guidelines of China. However, rescuers may be unable to maintain adequate compression or ventilation throughout a response of average emergency medical services because of increased rescuer fatigue. In the present study, we evaluated the performance of cardiopulmonary resuscitation (CPR) in training of military medical university students during a prolonged basic life support (BLS). METHODS: A 3-hour BLS training was given to 120 military medical university students. Six months after the training, 115 students performed single rescuer BLS on a manikin for 8 minutes. The qualities of chest compressions as well as ventilations were assessed. RESULTS: The average compression depth and rate were 53.7±5.3 mm and 135.1±15.7 compressions per minute respectively. The proportion of chest compressions with appropriate depth was 71.7%±28.4%. The average ventilation volume was 847.2±260.4 mL and the proportion of students with adequate ventilation was 63.5%. Compared with male students, significantly lower compression depth (46.7±4.8 vs. 54.6±4.8 mm, PCPR was found to be related to gender, body weight, and body mass index of students in this study. The quality of chest compressions was well maintained in male students during 8 minutes of conventional CPR but declined rapidly in female students after 2 minutes according to the latest national guidelines. Physical fitness and rescuer fatigue did not affect the quality of ventilation. PMID:26401177

Thermal modelling of a dry revolving vane compressor

Science.gov (United States)

Ooi, K. T.; Aw, K. T.

2017-08-01

The lubricant used in compressors serves to lubricate, to seal the gaps to reduce internal leakage and to a certain extent, to cool. However, a lubricant free compressor is attractive if lubricants become a source of contaminant, or in areas where the compressor needs be placed under any orientation, such as those in military or portable computing. In this paper, a thermal model for a dry revolving vane compressor is presented. This thermal model sets out to predict the steady-state operating temperatures of the compressor components. The lumped thermal conductance method was employed. The results of the components temperature will be presented and discussed. A high potential for overheating is observed at the shaft bearings.

Outsourcing Small Wars: Expanding the Role of Private Military Companies in U.S. Military Operations

National Research Council Canada - National Science Library

Jorgensen, Brent M

2005-01-01

"Outsourcing Small Wars: Expanding the Role of Private Military Companies in U.S. Military Operations" argues that, under current domestic and international laws, and current military regulations and doctrine...

Improvement of energy performances of existing buildings by application of solar thermal systems

Directory of Open Access Journals (Sweden)

Krstić-Furundžić Aleksandra

2009-01-01

Full Text Available Improvement of energy performances of the existing buildings in the suburban settlement Konjarnik in Belgrade, by the application of solar thermal systems is the topic presented in this paper. Hypothetical models of building improvements are created to allow the benefits of applying solar thermal collectors to residential buildings in Belgrade climate conditions to be estimated. This case study presents different design variants of solar thermal collectors integrated into a multifamily building envelope. The following aspects of solar thermal systems integration are analyzed in the paper: energy, architectural, ecological and economic. The results show that in Belgrade climatic conditions significant energy savings and reduction of CO2 emissions can be obtained with the application of solar thermal collectors.

Aqueous preparation of polyethylene glycol/sulfonated graphene phase change composite with enhanced thermal performance

International Nuclear Information System (INIS)

Li, Hairong; Jiang, Ming; Li, Qi; Li, Denian; Chen, Zongyi; Hu, Waping; Huang, Jing; Xu, Xizhe; Dong, Lijie; Xie, Haian; Xiong, Chuanxi

2013-01-01

Highlights: • We report an aqueous preparation technique of PEG/graphene phase change composite. • Hydrophilic sulfonated graphene (SG) nanosheets were synthesized. • Large increase in thermal conductivity is attained at low SG loading. • High latent heat is retained due to the low filler loading. • Affinity between SG and PEG contributes to the enhanced thermal performance. - Abstract: A polyethylene glycol (PEG)/sulfonated graphene (SG) phase change composite with enhanced thermal performance was prepared by solution processing in aqueous medium. It is remarkable that the addition of only 4 wt.% of SG to PEG could lead to a four times higher increase in thermal conductivity and a slight decrease in the phase change enthalpy, which is attributed to the formation of efficient thermal conductive network within the PEG matrix relevant to the excellent thermal property and unique 2-dimensional morphology of graphene as well as strong interface affinity between PEG matrix and SG nanosheets. The aqueous preparation technique is expected to pioneer a new way to prepare environment friendly organic phase change materials, and the production of PEG/SG composites is potentially scalable due to the facile fabricating process

Vedr.: Military capacity building

DEFF Research Database (Denmark)

Larsen, Josefine Kühnel; Struwe, Lars Bangert

2013-01-01

Military capacity building has increasingly become an integral part of Danish defence. Military capacity is a new way of thinking Danish defence and poses a new set of challenges and opportunities for the Danish military and the Political leadership. On the 12th of december, PhD. Candidate Josefine...... Kühnel Larsen and researcher Lars Bangert Struwe of CMS had organized a seminar in collaboration with Royal Danish Defense Colleg and the East African Security Governance Network. The seminar focused on some of the risks involved in Military capacity building and how these risks are dealt with from...

Analytical prediction of thermal performance of hypervapotron and its application to ITER

International Nuclear Information System (INIS)

Baxi, C.B.; Falter, H.

1992-09-01

A hypervapotron (HV) is a water cooled device made of high thermal conductivity material such as copper. A surface heat flux of up to 30 MW/m 2 has been achieved in copper hypervapotrans cooled by water at a velocity of 10 m/s and at a pressure of six bar. Hypervapotrons have been used in the past as beam dumps at the Joint European Torus (JET). It is planned to use them for diverter cooling during Mark II upgrade of the JET. Although a large amount of experimental data has been collected on these devices, an analytical performance prediction has not been done before due to the complexity of the heat transfer mechanisms. A method to analytically predict the thermal performance of the hypervapotron is described. The method uses a combination of a number of thermal hydraulic correlations and a finite element analysis. The analytical prediction shows an excellent agreement with experimental results over a wide range of velocities, pressures, subcooling, and geometries. The method was used to predict the performance of hypervapotron made of beryllium. Merits for the use of hypervapotrons for International Thermonuclear Experimental Reactor (ITER) and Tokamak Physics Experiment (TPX) are discussed

Military Dissent: What are the Ethical Implications of Tensions in U.S. Civil-Military Relations?

Science.gov (United States)

2013-06-14

ethical , and political. 22 Pfaff 1999, 8). The beliefs of egoism and post-modern relativism can be...MILITARY DISSENT: WHAT ARE THE ETHICAL IMPLICATIONS OF TENSIONS IN U.S. CIVIL-MILITARY RELATIONS? A thesis presented to the...JUN 2013 4. TITLE AND SUBTITLE Military Dissent: What are the Ethical Implications of Tensions in U.S. Civil-Military Relations? 5a. CONTRACT

Performance of Polycrystalline Photovoltaic and Thermal Collector (PVT on Serpentine-Parallel Absor

Directory of Open Access Journals (Sweden)

Mustofa

2015-10-01

Full Text Available This paper presents the performance of an unglazed polycrystalline photovoltaic-thermal PVT on 0.045 kg/s mass flow rate. PVT combine photovoltaic modules and solar thermal collectors, forming a single device that receive solar radiation and produces heat and electricity simultaneously. The collector figures out serpentine-parallel tubes that can prolong fluid heat conductivity from morning till afternoon. During testing, cell PV, inlet and outlet fluid temperatures were recorded by thermocouple digital LM35 Arduino Mega 2560. Panel voltage and electric current were also noted in which they were connected to computer and presented each second data recorded. But, in this performance only shows in the certain significant time data. This because the electric current was only noted by multimeter device not the digital one. Based on these testing data, average cell efficiency was about 19%, while thermal efficiency of above 50% and correspondent cell efficiency of 11%, respectively.

Experimental investigation on charging and discharging performance of absorption thermal energy storage system

International Nuclear Information System (INIS)

Zhang, Xiaoling; Li, Minzhi; Shi, Wenxing; Wang, Baolong; Li, Xianting

2014-01-01

Highlights: • A prototype of ATES using LiBr/H 2 O was designed and built. • Charging and discharging performances of ATES system were investigated. • ESE and ESD for cooling, domestic hot water and heating were obtained. - Abstract: Because of high thermal storage density and little heat loss, absorption thermal energy storage (ATES) is known as a potential thermal energy storage (TES) technology. To investigate the performance of the ATES system with LiBr–H 2 O, a prototype with 10 kW h cooling storage capacity was designed and built. The experiments demonstrated that charging and discharging processes are successful in producing 7 °C chilled water, 65 °C domestic hot water, or 43 °C heating water to meet the user’s requirements. Characteristics such as temperature, concentration and power variation of the ATES system during charging and discharging processes were investigated. The performance of the ATES system for supplying cooling, heating or domestic hot water was analyzed and compared. The results indicate that the energy storage efficiencies (ESE) for cooling, domestic hot water and heating are 0.51, 0.97, 1.03, respectively, and the energy storage densities (ESD) for cooling, domestic hot water and heating reach 42, 88, 110 kW h/m 3 , respectively. The performance is better than those of previous TES systems, which proves that the ATES system using LiBr–H 2 O may be a good option for thermal energy storage

78 FR 5717 - Safety Zone; Military Ocean Terminal Concord Safety Zone, Suisun Bay, Military Ocean Terminal...

Science.gov (United States)

2013-01-28

...-AA00 Safety Zone; Military Ocean Terminal Concord Safety Zone, Suisun Bay, Military Ocean Terminal... Guard is establishing a safety zone in the navigable waters of Suisun Bay near Military Ocean Terminal Concord, CA in support of military onload and offload operations. This safety zone is established to...

PLAY ACTIVITY WITH MILITARY TOYS AT PRESCHOOL AGE

Directory of Open Access Journals (Sweden)

Irina Nikolaevna Aleshina

2013-12-01

Full Text Available The article analyzes various attitudes to military toys, both positive and negative, existing in Russia and abroad. Toy weapons are viewed as a separate type of military toy. The study looks at the impact of military toys on children’s emotions and personality. The study looks at how children play games on their own and the way they organize them. We have conducted an experiment where three types of toys were used – military toys, soft toys and objects that act as toy substitutes. The study of games and the roles children took showed their poor playing skills. The research has detected existing connection between imagination and thinking ability and the children’s play activity. None of the children took the role of ‘the defender of the weak’ or ‘Patria’s defender’, which contradicts the results of an opinion survey of children’s parents who think that military toys help to develop ‘patriotism’, ‘courage’, and ‘teach to protect the weak’.Repeated observation of the way the same children play with military toys has shown that they take the role of defenders of the motherland or the weak only after watching TV-programmes or fiction films which show male characters defending their motherland or the weak using weapons, which shows that children’s games have social character.The experiment’s results detected what activity adults, who are concerned with the young generation’s attitude to weapons and violence, should perform. It is vital to strengthen children’s moral, ethical and cognitive spheres first, and only in second place fight against sales of military toys both in Russia and abroad.DOI: http://dx.doi.org/10.12731/2218-7405-2013-8-53

Thermal performance modeling of cross-flow heat exchangers

CERN Document Server

Cabezas-Gómez, Luben; Saíz-Jabardo, José Maria

2014-01-01

This monograph introduces a numerical computational methodology for thermal performance modeling of cross-flow heat exchangers, with applications in chemical, refrigeration and automobile industries. This methodology allows obtaining effectiveness-number of transfer units (e-NTU) data and has been used for simulating several standard and complex flow arrangements configurations of cross-flow heat exchangers. Simulated results have been validated through comparisons with results from available exact and approximate analytical solutions. Very accurate results have been obtained over wide ranges

Thermal Performance and Operation Limit of Heat Pipe Containing Neutron Absorber

Energy Technology Data Exchange (ETDEWEB)

Kim, Kyung Mo; Jeong, Yeong Shin; Kim, In Guk; Bang, In Choel [UNIST, Ulsan (Korea, Republic of)

2015-05-15

Recently, passive safety systems are under development to ensure the core cooling in accidents involving impossible depressurization such as station blackout (SBO). Hydraulic control rod drive mechanisms, passive auxiliary feedwater system (PAFS), Passive autocatalystic recombiner (PAR), and so on are types of passive safety systems to enhance the safety of nuclear power plants. Heat pipe is used in various engineering fields due to its advantages in terms of easy fabrication, high heat transfer rate, and passive heat transfer. Also, the various concepts associated with safety system and heat transfer using the heat pipe were developed in nuclear engineering field.. Thus, our group suggested the hybrid control rod which combines the functions of existing control rod and heat pipe. If there is significant temperature difference between active core and condenser, the hybrid control rod can shutdown the nuclear fission reaction and remove the decay heat from the core to ultimate heat sink. The unique characteristic of the hybrid control rod is the presence of neutron absorber inside the heat pipe. Many previous researchers studied the effect of parameters on the thermal performance of heat pipe. However, the effect of neutron absorber on the thermal performance of heat pipe has not been investigated. Thus, the annular heat pipe which contains B{sub 4}C pellet in the normal heat pipe was prepared and the thermal performance of the annular heat pipe was studied in this study. Hybrid control rod concept was developed as a passive safety system of nuclear power plant to ensure the safety of the reactor at accident condition. The hybrid control rod must contain the neutron absorber for the function as a control rod. So, the effect of neutron absorber on the thermal performance of heat pipe was experimentally investigated in this study. Temperature distributions at evaporator section of annular heat pipe were lower than normal heat pipe due to the larger volume occupied by

Military Personnel Who Seek Health and Mental Health Services Outside the Military.

Science.gov (United States)

Waitzkin, Howard; Cruz, Mario; Shuey, Bryant; Smithers, Daniel; Muncy, Laura; Noble, Marylou

2018-05-01

Although research conducted within the military has assessed the health and mental health problems of military personnel, little information exists about personnel who seek care outside the military. The purpose of this study is to clarify the personal characteristics, mental health diagnoses, and experiences of active duty U.S. military personnel who sought civilian sector services due to unmet needs for care. This prospective, multi-method study included 233 clients, based in the United States, Afghanistan, South Korea, and Germany, who obtained care between 2013 and 2016 from a nationwide network of volunteer civilian practitioners. A hotline organized by faith-based and peace organizations received calls from clients and referred them to the network when the clients described unmet needs for physical or mental health services. Intake and follow-up interviews at 2 wk and 2 mo after intake captured demographic characteristics, mental health diagnoses, and reasons for seeking civilian rather than military care. Non-parametric bootstrap regression analyses identified predictors of psychiatric disorders, suicidality, and absence without leave (AWOL). Qualitative analyses of clients' narratives clarified their experiences and reasons for seeking care. The research protocol has been reviewed and approved annually by the Institutional Review Board at the University of New Mexico. Depression (72%), post-traumatic stress disorder (62%), alcohol use disorder (27%), and panic disorder (25%) were the most common diagnoses. Forty-eight percent of clients reported suicidal ideation. Twenty percent were absence without leave. Combat trauma predicted post-traumatic stress disorder (odds ratio [OR] = 8.84, 95% confidence interval [CI] 1.66, 47.12, p = 0.01) and absence without leave (OR = x3.85, 95% CI 1.14, 12.94, p = 0.03). Non-combat trauma predicted panic disorder (OR = 3.64, 95% CI 1.29, 10.23, p = 0.01). Geographical region was associated with generalized anxiety disorder

Effects of synergetic and antagonistic additive elements on the thermal performance of engine oils at various bulk temperatures

International Nuclear Information System (INIS)

Abou-Ziyan, H.; Mahmoud, M.; Al-Ajmi, R.; Shedid, M.

2015-01-01

This paper reports effects of additive elements on thermal performance of engine oils during cooling of different engine parts at bulk temperatures from 40 to 150 °C and average wall superheat of 100 °C. The analysis is performed using a back propagation neural network that was trained on experimentally obtained sub-cooled boiling data of engine oils. The results demonstrate that sodium, boron, molybdenum, magnesium and barium additive elements are thermally synergetic while phosphorous, zinc, calcium and silicon elements are thermally antagonistic. Experimental thermal performance of oils could potentially be improved by increasing the concentration of synergetic additive elements or decreasing antagonistic additive elements concentration. - Highlights: • Oil additives enhance lubrication properties but may hinder oil thermal performance. • Sodium, boron, molybdenum, magnesium and barium additives enhance heat transfer. • Additives containing phosphorous, zinc, calcium and silicon hinder the heat transfer. • Oil thermal performance is improved by changing some oil additives concentrations. • Some additives are highly sensitive to interaction with other additives in the oil.

Reliability residual-life prediction method for thermal aging based on performance degradation

International Nuclear Information System (INIS)

Ren Shuhong; Xue Fei; Yu Weiwei; Ti Wenxin; Liu Xiaotian

2013-01-01

The paper makes the study of the nuclear power plant main pipeline. The residual-life of the main pipeline that failed due to thermal aging has been studied by the use of performance degradation theory and Bayesian updating methods. Firstly, the thermal aging impact property degradation process of the main pipeline austenitic stainless steel has been analyzed by the accelerated thermal aging test data. Then, the thermal aging residual-life prediction model based on the impact property degradation data is built by Bayesian updating methods. Finally, these models are applied in practical situations. It is shown that the proposed methods are feasible and the prediction accuracy meets the needs of the project. Also, it provides a foundation for the scientific management of aging management of the main pipeline. (authors)

Minds “At Attention”: Mindfulness Training Curbs Attentional Lapses in Military Cohorts

Science.gov (United States)

Jha, Amishi P.; Morrison, Alexandra B.; Dainer-Best, Justin; Parker, Suzanne; Rostrup, Nina; Stanley, Elizabeth A.

2015-01-01

We investigated the impact of mindfulness training (MT) on attentional performance lapses associated with task-unrelated thought (i.e., mind wandering). Periods of persistent and intensive demands may compromise attention and increase off-task thinking. Here, we investigated if MT may mitigate these deleterious effects and promote cognitive resilience in military cohorts enduring a high-demand interval of predeployment training. To better understand which aspects of MT programs are most beneficial, three military cohorts were examined. Two of the three groups were provided MT. One group received an 8-hour, 8-week variant of Mindfulness-based Mind Fitness Training (MMFT) emphasizing engagement in training exercises (training-focused MT, n = 40), a second group received a didactic-focused variant emphasizing content regarding stress and resilience (didactic-focused MT, n = 40), and the third group served as a no-training control (NTC, n = 24). Sustained Attention to Response Task (SART) performance was indexed in all military groups and a no-training civilian group (CIV, n = 45) before (T1) and after (T2) the MT course period. Attentional performance (measured by A’, a sensitivity index) was lower in NTC vs. CIV at T2, suggesting that performance suffers after enduring a high-demand predeployment interval relative to a similar time period of civilian life. Yet, there were significantly fewer performance lapses in the military cohorts receiving MT relative to NTC, with training-focused MT outperforming didactic-focused MT at T2. From T1 to T2, A’ degraded in NTC and didactic-focused MT but remained stable in training-focused MT and CIV. In sum, while protracted periods of high-demand military training may increase attentional performance lapses, practice-focused MT programs akin to training-focused MT may bolster attentional performance more than didactic-focused programs. As such, training-focused MT programs should be further examined in cohorts experiencing

Design and thermal performances of a scalable linear Fresnel reflector solar system

International Nuclear Information System (INIS)

Zhu, Yanqing; Shi, Jifu; Li, Yujian; Wang, Leilei; Huang, Qizhang; Xu, Gang

2017-01-01

Highlights: • A scalable linear Fresnel reflector which can supply different temperatures is proposed. • Inclination design of the mechanical structure is used to reduce the end losses. • The maximum thermal efficiency of 64% is achieved in Guangzhou. - Abstract: This paper proposes a scalable linear Fresnel reflector (SLFR) solar system. The optical mirror field which contains an array of linear plat mirrors closed to each other is designed to eliminate the inter-low shading and blocking. Scalable mechanical mirror support which can place different number of mirrors is designed to supply different temperatures. The mechanical structure can be inclined to reduce the end losses. Finally, the thermal efficiency of the SLFR with two stage mirrors is tested. After adjustment, the maximum thermal efficiency of 64% is obtained and the mean thermal efficiency is higher than that before adjustment. The results indicate that the end losses have been reduced effectively by the inclination design and excellent thermal performance can be obtained by the SLFR after adjustment.

The effects of military body armour on trunk and hip kinematics during performance of manual handling tasks (.).

Science.gov (United States)

Lenton, Gavin; Aisbett, Brad; Neesham-Smith, Daniel; Carvajal, Alvaro; Netto, Kevin

2016-06-01

Musculoskeletal injuries are reported as burdening the military. An identified risk factor for injury is carrying heavy loads; however, soldiers are also required to wear their load as body armour. To investigate the effects of body armour on trunk and hip kinematics during military-specific manual handling tasks, 16 males completed 3 tasks while wearing each of 4 body armour conditions plus a control. Three-dimensional motion analysis captured and quantified all kinematic data. Average trunk flexion for the weightiest armour type was higher compared with control during the carry component of the ammunition box lift (p armour types compared with control during the ammunition box place component (p armour occurred independent of armour design. In order to optimise armour design, manufacturers need to work with end-users to explore how armour configurations interact with range of personal and situational factors in operationally relevant environments. Practitioner Summary: Musculoskeletal injuries are reported as burdening the military and may relate to body armour wear. Body armour increased trunk flexion and reduced trunk rotation during military-specific lifting and carrying tasks. The altered kinematics may contribute to injury risk, but more research is required.

Comparison of Thermal Performances between Low Porosity Perforate Plate and Flat Plate Solar Air Collector

Science.gov (United States)

Chan, Hoy-Yen; Vinson, A. A.; Baljit, S. S. S.; Ruslan, M. H.

2018-04-01

Flat plate solar air collector is the most common collector design, which is relatively simpler to fabricate and lower cost. In the present study, perforated plate solar collector was developed to improve the system thermal performance. A glazed perforated plate of 6mm holes diameter with square geometry was designed and installed as the absorber of the collector. The influences of solar radiation intensity and mass flow rate on the thermal performance were investigated. The perforated collector was compared with the flat plate solar collector under the same operating conditions. The highest values of thermal efficiency in this study for the perforated plate (PP) and the flat plate (FP) solar collectors were 59% and 36% respectively, at solar radiation intensity of 846 Wm-2 and mass flow rate of 0.02 kgs-1. Furthermore, PP collector gave better thermal performance compared to FP collector; and compared to previous studies, the present perforated design was compatible with the flat plate with double pass designs.

Influence of military sexual assault and other military stressors on substance use disorder and PTS symptomology in female military veterans.

Science.gov (United States)

Yalch, Matthew M; Hebenstreit, Claire L; Maguen, Shira

2018-05-01

Servicewomen exposed to traumatic stressors over the course of their military service are at increased risk of developing symptoms of substance use disorder (SUD) and posttraumatic stress (PTS). They are also at risk for exposure to military sexual assault (MSA), which is also associated with SUD and PTS symptomology. Research is unclear about the incremental contributions of different forms of traumatic stressors on co-occurring SUD and PTS symptomology. In this study we examined the independent and combined effects of MSA and other military stressors on SUD and PTS symptomology in a sample of female veterans (N=407). Results indicate that MSA and other military stressors exhibit incremental effects on SUD and PTS symptomology. Results further suggest that women exposed to both MSA and other military stressors are at increased risk for developing co-occurring SUD and PTSD. These findings extend previous research on comorbid SUD and PTSD, highlighting the cumulative effects of traumatic stressors on posttraumatic psychopathology, and have implications for future research and clinical practice with female veterans. Copyright © 2017 Elsevier Ltd. All rights reserved.

Forecasting military expenditure

Directory of Open Access Journals (Sweden)

Tobias Böhmelt

2014-05-01

Full Text Available To what extent do frequently cited determinants of military spending allow us to predict and forecast future levels of expenditure? The authors draw on the data and specifications of a recent model on military expenditure and assess the predictive power of its variables using in-sample predictions, out-of-sample forecasts and Bayesian model averaging. To this end, this paper provides guidelines for prediction exercises in general using these three techniques. More substantially, however, the findings emphasize that previous levels of military spending as well as a country’s institutional and economic characteristics particularly improve our ability to predict future levels of investment in the military. Variables pertaining to the international security environment also matter, but seem less important. In addition, the results highlight that the updated model, which drops weak predictors, is not only more parsimonious, but also slightly more accurate than the original specification.

Worldwide Military Spending, 1990-1995

OpenAIRE

Jerald A Schiff; Benedict J. Clements; Sanjeev Gupta

1996-01-01

The decline in military spending that began in the mid-1980s continued through 1995, and this decline was widespread both geographically and by level of development. Cuts in military spending appear to have potentially important implications for nonmilitary spending and fiscal adjustment. In contrast to findings for previous periods, military spending has declined more than proportionately in those countries that have reduced total spending. Countries with Fund programs have reduced military ...

PREDICTING THERMAL PERFORMANCE OF ROOFING SYSTEMS IN SURABAYA

Directory of Open Access Journals (Sweden)

MINTOROGO Danny Santoso

2015-07-01

Full Text Available Traditional roofing systems in the developing country likes Indonesia are still be dominated by the 30o, 45o, and more pitched angle roofs; the roofing cover materials are widely used to traditional clay roof tiles, then modern concrete roof tiles, and ceramic roof tiles. In the 90’s decay, shop houses are prosperous built with flat concrete roofs dominant. Green roofs and roof ponds are almost rarely built to meet the sustainable environmental issues. Some tested various roof systems in Surabaya were carried out to observe the roof thermal performances. Mathematical equation model from three references are also performed in order to compare with the real project tested. Calculated with equation (Kabre et al., the 30o pitched concrete-roof-tile, 30o clay-roof-tile, 45o pitched concrete-roof-tile are the worst thermal heat flux coming to room respectively. In contrast, the bare soil concrete roof and roof pond system are the least heat flux streamed onto room. Based on predicted calculation without insulation and cross-ventilation attic space, the roof pond and bare soil concrete roof (greenery roof are the appropriate roof systems for the Surabaya’s climate; meanwhile the most un-recommended roof is pitched 30o or 45o angle with concrete-roof tiles roofing systems.

High-performance polyamide thin-film composite nanofiltration membrane: Role of thermal treatment

Science.gov (United States)

Liu, Baicang; Wang, Shuai; Zhao, Pingju; Liang, Heng; Zhang, Wen; Crittenden, John

2018-03-01

Nanofiltration (NF) membranes have many excellent applications (e.g., removing multivalent ions and pretreating water before reverse osmosis, RO), but their relatively high cost limits their application. Especially in recent years, researchers have paid substantial attention to reducing the cost of NF membranes. In this paper, high-performance NF membranes were fabricated using interfacial polymerization (IP) methods. The polymer concentration, IP solution concentration, and thermal treatment conditions were varied. The synthesized membranes were characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), a contact angle goniometer, X-ray photoelectron spectroscopy (XPS), attenuated total reflectance fourier transform infrared (ATR-FTIR) spectroscopy, and performance tests. The results show that water flux was significantly improved using a hot-water thermal treatment method. Our fabricated thermal-treated NF membrane had an approximately 15% higher water permeability with a value of 13.6 L/(m2 h bar) than that of the commercially available GE HL membrane with a value of 11.8 L/(m2 h bar). Our membranes had the same MgSO4 rejection as that of the GE HL membrane. We found that the thermal treatment causes the NF membrane surface to be smoother and have a high crosslinking degree.

THE DEMOCRATIC CONTROL OF MILITARY FORCES

Directory of Open Access Journals (Sweden)

Smail Oštraković

2011-04-01

Full Text Available The transition requirement for post communism countries, especially the part that is about military forces is to establish those civil-military relation that will have prepared projects for awareness evolving of society and military about necessity of democratic control over military sector of country through development of many different communication forms and shapes. Before everything, it means the entire freedom and independence of media at access to military forces as the topic and subject of its interests and also the organization of public military communication system as integral part of information-communication system in society

48 CFR 252.225-7010 - Commercial Derivative Military Article-Specialty Metals Compliance Certificate.

Science.gov (United States)

2010-10-01

... articles it intends to deliver under any contract resulting from this solicitation using the alternative... military articles in paragraph (b) of this provision, the offeror certifies that, if awarded a contract as... the period of contract performance in the production of each commercial derivative military article...

Thermal Performance of a Cryogenic Fluid Management Cubesat Mission

Science.gov (United States)

Berg, J. J.; Oliveira, J. M.; Congiardo, J. F.; Walls, L. K.; Putman, P. T.; Haberbusch, M. S.

2013-01-01

Development for an in-space demonstration of a CubeS at as a Cryogenic Fluid Management (CFM) test bed is currently underway. The favorable economics of CubeSats make them appealing for technology development activity. While their size limits testing to smaller scales, many of the regimes relevant to CFM can still be achieved. The first demo flight of this concept, CryoCube®-1, will focus on oxygen liquefaction and low-gravity level sensing using Reduced Gravity CryoTracker®. An extensive thermal modeling effort has been underway to both demonstrate concept feasibility and drive the prototype design. The satellite will utilize both a sun- and earth-shield to passively cool its experimental tank below 115 K. An on-board gas generator will create high pressure gaseous oxygen, which will be throttled into a bottle in the experimental node and condensed. The resulting liquid will be used to perform various experiments related to level sensing. Modeling efforts have focused on the spacecraft thermal performance and its effects on condensation in the experimental node. Parametric analyses for both optimal and suboptimal conditions have been considered and are presented herein.

Thermal effects on human performance in office environment measured by integrating task speed and accuracy

DEFF Research Database (Denmark)

Lan, Li; Wargocki, Pawel; Lian, Zhiwei

2014-01-01

We have proposed a method in which the speed and accuracy can be integrated into one metric of human performance. This was achieved by designing a performance task in which the subjects receive feedback on their performance by informing them whether they have committed errors, and if did, they can......, 12 subjects performed tasks under two thermal conditions (neutral & warm) repeatedly. The tasks were presented with and without feedback on errors committed, as outlined above. The results indicate that there was a greater decrease in task performance due to thermal discomfort when feedback was given......, compared to the performance of tasks presented without feedback....

Application of monitoring, diagnosis, and prognosis in thermal performance analysis for nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyeong Min; Heo, Gyun Young [Kyung Hee University, Yongin (Korea, Republic of); Na, Man Gyun [Chosun University, Gwangju (Korea, Republic of)

2014-12-15

As condition-based maintenance (CBM) has risen as a new trend, there has been an active movement to apply information technology for effective implementation of CBM in power plants. This motivation is widespread in operations and maintenance, including monitoring, diagnosis, prognosis, and decision-making on asset management. Thermal efficiency analysis in nuclear power plants (NPPs) is a longstanding concern being updated with new methodologies in an advanced IT environment. It is also a prominent way to differentiate competitiveness in terms of operations and maintenance costs. Although thermal performance tests implemented using industrial codes and standards can provide officially trustworthy results, they are essentially resource-consuming and maybe even a hind-sighted technique rather than a foresighted one, considering their periodicity. Therefore, if more accurate performance monitoring can be achieved using advanced data analysis techniques, we can expect more optimized operations and maintenance. This paper proposes a framework and describes associated methodologies for in-situ thermal performance analysis, which differs from conventional performance monitoring. The methodologies are effective for monitoring, diagnosis, and prognosis in pursuit of CBM. Our enabling techniques cover the intelligent removal of random and systematic errors, deviation detection between a best condition and a currently measured condition, degradation diagnosis using a structured knowledge base, and prognosis for decision-making about maintenance tasks. We also discuss how our new methods can be incorporated with existing performance tests. We provide guidance and directions for developers and end-users interested in in-situ thermal performance management, particularly in NPPs with large steam turbines.

Application of monitoring, diagnosis, and prognosis in thermal performance analysis for nuclear power plants

International Nuclear Information System (INIS)

Kim, Hyeong Min; Heo, Gyun Young; Na, Man Gyun

2014-01-01

As condition-based maintenance (CBM) has risen as a new trend, there has been an active movement to apply information technology for effective implementation of CBM in power plants. This motivation is widespread in operations and maintenance, including monitoring, diagnosis, prognosis, and decision-making on asset management. Thermal efficiency analysis in nuclear power plants (NPPs) is a longstanding concern being updated with new methodologies in an advanced IT environment. It is also a prominent way to differentiate competitiveness in terms of operations and maintenance costs. Although thermal performance tests implemented using industrial codes and standards can provide officially trustworthy results, they are essentially resource-consuming and maybe even a hind-sighted technique rather than a foresighted one, considering their periodicity. Therefore, if more accurate performance monitoring can be achieved using advanced data analysis techniques, we can expect more optimized operations and maintenance. This paper proposes a framework and describes associated methodologies for in-situ thermal performance analysis, which differs from conventional performance monitoring. The methodologies are effective for monitoring, diagnosis, and prognosis in pursuit of CBM. Our enabling techniques cover the intelligent removal of random and systematic errors, deviation detection between a best condition and a currently measured condition, degradation diagnosis using a structured knowledge base, and prognosis for decision-making about maintenance tasks. We also discuss how our new methods can be incorporated with existing performance tests. We provide guidance and directions for developers and end-users interested in in-situ thermal performance management, particularly in NPPs with large steam turbines.

Fix These First: How the World's Leading Companies Point the Way Toward High Reliability in the Military Health System.

Science.gov (United States)

Beauvais, Brad; Richter, Jason; Brezinski, Paul

The 2014 Military Health System Review calls for healthcare system leaders to implement effective strategies used by other high-performing organizations. The authors state, " the [military health system] MHS can create an optimal healthcare environment that focuses on continuous quality improvement where every patient receives safe, high-quality care at all times" (Military Health System, 2014, p. 1). Although aspirational, the document does not specify how a highly reliable health system is developed or what systemic factors are necessary to sustain highly reliable performance. Our work seeks to address this gap and provide guidance to MHS leaders regarding how high-performing organizations develop exceptional levels of performance.The authors' expectation is that military medicine will draw on these lessons to enhance leadership, develop exceptional organizational cultures, onboard and engage employees, build customer loyalty, and improve quality of care. Leaders from other segments of the healthcare field likely will find this study valuable given the size of the military healthcare system (9.6 million beneficiaries), the United States' steady progression toward population-based health, and the increasing need for highly reliable systems and performance.

Cost and performance analysis of concentrating solar power systems with integrated latent thermal energy storage

International Nuclear Information System (INIS)

Nithyanandam, K.; Pitchumani, R.

2014-01-01

Integrating TES (thermal energy storage) in a CSP (concentrating solar power) plant allows for continuous operation even during times when solar irradiation is not available, thus providing a reliable output to the grid. In the present study, the cost and performance models of an EPCM-TES (encapsulated phase change material thermal energy storage) system and HP-TES (latent thermal storage system with embedded heat pipes) are integrated with a CSP power tower system model utilizing Rankine and s-CO 2 (supercritical carbon-dioxide) power conversion cycles, to investigate the dynamic TES-integrated plant performance. The influence of design parameters of the storage system on the performance of a 200 MW e capacity power tower CSP plant is studied to establish design envelopes that satisfy the U.S. Department of Energy SunShot Initiative requirements, which include a round-trip annualized exergetic efficiency greater than 95%, storage cost less than $15/kWh t and LCE (levelized cost of electricity) less than 6 ¢/kWh. From the design windows, optimum designs of the storage system based on minimum LCE, maximum exergetic efficiency, and maximum capacity factor are reported and compared with the results of two-tank molten salt storage system. Overall, the study presents the first effort to construct and analyze LTES (latent thermal energy storage) integrated CSP plant performance that can help assess the impact, cost and performance of LTES systems on power generation from molten salt power tower CSP plant. - Highlights: • Presents technoeconomic analysis of thermal energy storage integrated concentrating solar power plants. • Presents a comparison of different storage options. • Presents optimum design of thermal energy storage system for steam Rankine and supercritical carbon dioxide cycles. • Presents designs for maximizing exergetic efficiency while minimizing storage cost and levelized cost of energy

Surface-restrained growth of vertically aligned carbon nanotube arrays with excellent thermal transport performance.

Science.gov (United States)

Ping, Linquan; Hou, Peng-Xiang; Liu, Chang; Li, Jincheng; Zhao, Yang; Zhang, Feng; Ma, Chaoqun; Tai, Kaiping; Cong, Hongtao; Cheng, Hui-Ming

2017-06-22

A vertically aligned carbon nanotube (VACNT) array is a promising candidate for a high-performance thermal interface material in high-power microprocessors due to its excellent thermal transport property. However, its rough and entangled free tips always cause poor interfacial contact, which results in serious contact resistance dominating the total thermal resistance. Here, we employed a thin carbon cover to restrain the disorderly growth of the free tips of a VACNT array. As a result, all the free tips are seamlessly connected by this thin carbon cover and the top surface of the array is smoothed. This unique structure guarantees the participation of all the carbon nanotubes in the array in the heat transport. Consequently the VACNT array grown on a Cu substrate shows a record low thermal resistance of 0.8 mm 2 K W -1 including the two-sided contact resistances, which is 4 times lower than the best result previously reported. Remarkably, the VACNT array can be easily peeled away from the Cu substrate and act as a thermal pad with excellent flexibility, adhesive ability and heat transport capability. As a result the CNT array with a thin carbon cover shows great potential for use as a high-performance flexible thermal interface material.

Thermal performance enhancement of erythritol/carbon foam composites via surface modification of carbon foam

Science.gov (United States)

Li, Junfeng; Lu, Wu; Luo, Zhengping; Zeng, Yibing

2017-03-01

The thermal performance of the erythritol/carbon foam composites, including thermal diffusivity, thermal capacity, thermal conductivity and latent heat, were investigated via surface modification of carbon foam using hydrogen peroxide as oxider. It was found that the surface modification enhanced the wetting ability of carbon foam surface to the liquid erythritol of the carbon foam surface and promoted the increase of erythritol content in the erythritol/carbon foam composites. The dense interfaces were formed between erythritol and carbon foam, which is due to that the formation of oxygen functional groups C=O and C-OH on the carbon surface increased the surface polarity and reduced the interface resistance of carbon foam surface to the liquid erythritol. The latent heat of the erythritol/carbon foam composites increased from 202.0 to 217.2 J/g through surface modification of carbon foam. The thermal conductivity of the erythritol/carbon foam composite before and after surface modification further increased from 40.35 to 51.05 W/(m·K). The supercooling degree of erythritol also had a large decrease from 97 to 54 °C. Additionally, the simple and effective surface modification method of carbon foam provided an extendable way to enhance the thermal performances of the composites composed of carbon foams and PCMs.

Military Expenditure, Threats, and Growth

OpenAIRE

Aizenman, Joshua; Glick, Reuven

2003-01-01

This paper clarifies one of the puzzling results of the economic growth literature: the impact of military expenditure is frequently found to be non-significant or negative, yet most countries spend a large fraction of their GDP on defense and the military. We start by empirical evaluation of the non- linear interactions between military expenditure, external threats, corruption, and other relevant controls. While growth falls with higher levels of military spending, given the values of the o...

Postpartum fatigue in the active-duty military woman.

Science.gov (United States)

Rychnovsky, Jacqueline D

2007-01-01

(a) To describe fatigue levels in military active-duty women, (b) to describe the relationship among selected predictor variables of fatigue, and (c) to examine the relationship between predictor variables, fatigue levels, and performance (as measured by functional status) after childbirth. Based on the Theory of Unpleasant Symptoms, a longitudinal, prospective design. A large military medical facility in the southwest United States. A convenience sample of 109 military active-duty women. Postpartum fatigue. Women were found to be moderately fatigued across time, with no change in fatigue levels from 2 to 6 weeks after delivery. All variables correlated with fatigue during hospitalization and at 2 weeks after delivery, and depression, anxiety, maternal sleep, and functional status correlated with fatigue at 6 weeks after delivery. Regression analyses indicated that maternal anxiety predicted fatigue at 6 weeks after delivery. Over half the women had not regained full functional status when they returned to work, and 40% still displayed symptoms of postpartum depression and anxiety. Military women continue to experiencing postpartum fatigue when they return to the workplace. Future research is needed to examine issues surrounding fatigue and its associated variables during the first year after delivery.

Unintended pregnancies among women serving in the Israeli military.

Science.gov (United States)

Rottenstreich, Misgav; Loitner, Limor; Dar, Shir; Kedem, Ron; Smorgick, Noam; Vaknin, Zvi

2017-07-01

The objective was to identify the prevalence of and variables associated with unintended pregnancy among young, unmarried women serving in the Israeli military. We performed a retrospective cohort study of unmarried women drafted by the Israeli military between 2013 and 2015 at the age of 18 years. We used multivariable logistic regression to examine associations between unintended pregnancy and women's education, IQ, immigration status, country of origin, neighborhood socioeconomic status and history of psychiatric illness. Most women (n=127,262) did not become pregnant while serving in the Israeli military. Unintended pregnancy was reported by 2365, with an additional 6 women reporting pregnancy resulting from sexual assault and 5 an intended pregnancy. Annual rates of unintended pregnancy among young women serving in the Israeli military declined from 1.69% in 2013 to 1.56% in 2014 and 1.33% in 2015. In multivariable models, unintended pregnancy was more common among women soldiers who had not graduated from high school (adjusted relative risk [RR], 5.3; 95% confidence interval [CI], 4.69-6.04) and those who were first-generation immigrants (adjusted RR, 2.1; 95% CI, 1.90-2.35). Unintended pregnancy is rare among women serving into the Israeli military. Increasing contraceptive use among women who have not graduated from high school may further reduce rates of unintended pregnancy among women serving in the Israeli military. Copyright © 2017 Elsevier Inc. All rights reserved.

Thermal Performance of Cryogenic Multilayer Insulation at Various Layer Spacings

Science.gov (United States)

Johnson, Wesley Louis

2010-01-01

Multilayer insulation (MLI) has been shown to be the best performing cryogenic insulation system at high vacuum (less that 10 (exp 3) torr), and is widely used on spaceflight vehicles. Over the past 50 years, many investigations into MLI have yielded a general understanding of the many variables that are associated with MLI. MLI has been shown to be a function of variables such as warm boundary temperature, the number of reflector layers, and the spacer material in between reflectors, the interstitial gas pressure and the interstitial gas. Since the conduction between reflectors increases with the thickness of the spacer material, yet the radiation heat transfer is inversely proportional to the number of layers, it stands to reason that the thermal performance of MLI is a function of the number of layers per thickness, or layer density. Empirical equations that were derived based on some of the early tests showed that the conduction term was proportional to the layer density to a power. This power depended on the material combination and was determined by empirical test data. Many authors have graphically shown such optimal layer density, but none have provided any data at such low densities, or any method of determining this density. Keller, Cunnington, and Glassford showed MLI thermal performance as a function of layer density of high layer densities, but they didn't show a minimal layer density or any data below the supposed optimal layer density. However, it was recently discovered that by manipulating the derived empirical equations and taking a derivative with respect to layer density yields a solution for on optimal layer density. Various manufacturers have begun manufacturing MLI at densities below the optimal density. They began this based on the theory that increasing the distance between layers lowered the conductive heat transfer and they had no limitations on volume. By modifying the circumference of these blankets, the layer density can easily be

Performance study of heat-pipe solar photovoltaic/thermal heat pump system

International Nuclear Information System (INIS)

Chen, Hongbing; Zhang, Lei; Jie, Pengfei; Xiong, Yaxuan; Xu, Peng; Zhai, Huixing

2017-01-01

Highlights: • The testing device of HPS PV/T heat pump system was established by a finished product of PV panel. • A detailed mathematical model of heat pump was established to investigate the performance of each component. • The dynamic and static method was combined to solve the mathematical model of HPS PV/T heat pump system. • The HPS PV/T heat pump system was optimized by the mathematical model. • The influence of six factors on the performance of HPS PV/T heat pump system was analyzed. - Abstract: A heat-pipe solar (HPS) photovoltaic/thermal (PV/T) heat pump system, combining HPS PV/T collector with heat pump, is proposed in this paper. The HPS PV/T collector integrates heat pipes with PV panel, which can simultaneously generate electricity and thermal energy. The extracted heat from HPS PV/T collector can be used by heat pump, and then the photoelectric conversion efficiency is substantially improved because of the low temperature of PV cells. A mathematical model of the system is established in this paper. The model consists of a dynamic distributed parameter model of the HPS PV/T collection system and a quasi-steady state distributed parameter model of the heat pump. The mathematical model is validated by testing data, and the dynamic performance of the HPS PV/T heat pump system is discussed based on the validated model. Using the mathematical model, a reasonable accuracy in predicting the system’s dynamic performance with a relative error within ±15.0% can be obtained. The capacity of heat pump and the number of HPS collectors are optimized to improve the system performance based on the mathematical model. Six working modes are proposed and discussed to investigate the effect of solar radiation, ambient temperature, supply water temperature in condenser, PV packing factor, heat pipe pitch and PV backboard absorptivity on system performance by the validated model. It is found that the increase of solar radiation, ambient temperature and PV

Thermal insulation performance of green roof systems

Energy Technology Data Exchange (ETDEWEB)

Celik, Serdar; Morgan, Susan; Retzlaff, William; Once, Orcun [southern Illinois University (United States)], e-mail: scelik@siue.edu, e-mail: smorgan@siue.edu, e-mail: wretzla@siue.edu, e-mail: oonce@siue.edu

2011-07-01

With the increasing costs of energy, good building insulation has become increasingly important. Among existing insulation techniques is the green roof system, which consists of covering the roof of a building envelop with plants. The aim of this paper is to assess the impact of vegetation type and growth media on the thermal performance of green roof systems. Twelve different green roof samples were made with 4 different growth media and 3 sedum types. Temperature at the sample base was recorded every 15 minutes for 3 years; the insulation behavior was then analysed. Results showed that the insulation characteristics were achieved with a combination of haydite and sedum sexangulare. This study demonstrated that the choice of growth media and vegetation is important to the green roof system's performance; further research is required to better understand the interactions between growth media and plant roots.

Thermal dependence of sprint performance in the lizard Psammodromus algirus along a 2200-meter elevational gradient: Cold-habitat lizards do not perform better at low temperatures.

Science.gov (United States)

Zamora-Camacho, Francisco Javier; Rubiño-Hispán, María Virtudes; Reguera, Senda; Moreno-Rueda, Gregorio

2015-08-01

Sprint speed has a capital relevance in most animals' fitness, mainly for fleeing from predators. Sprint performance is maximal within a certain range of body temperatures in ectotherms, whose thermal upkeep relies on exogenous thermal sources. Ectotherms can respond to diverse thermal environments either by shifting their thermal preferences or maintaining them through different adaptive mechanisms. Here, we tested whether maximum sprint speed of a lizard that shows conservative thermal ecology along a 2200-meter elevational gradient differs with body temperature in lizards from different elevations. Lizards ran faster at optimum than at suboptimum body temperature. Notably, high-elevation lizards were not faster than mid- and low-elevation lizards at suboptimum body temperature, despite their low-quality thermal environment. This result suggests that both preferred body temperature and thermal dependence of speed performance are co-adapted along the elevational gradient. High-elevation lizards display a number of thermoregulatory strategies that allow them to achieve high optimum body temperatures in a low thermal-quality habitat and thus maximize speed performance. As for reproductive condition, we did not find any effect of it on sprint speed, or any significant interaction with elevation or body temperature. However, strikingly, gravid females were significantly slower than males and non-gravid females at suboptimum temperature, but performed similarly well at optimal temperature. Copyright © 2015 Elsevier Ltd. All rights reserved.

Experimental results pertaining to the performance of thermal igniters

International Nuclear Information System (INIS)

Carmel, M.K.

1989-10-01

This report summarizes the results of various experimental programs regarding the performance of thermal igniters for the deliberate ignition of hydrogen in light water reactors. Experiments involving both premixed combustion and combustion with continuous hydrogen injection are reviewed. Combustion characteristics examined include flammability limits of hydrogen:air and hydrogen:air:steam mixtures, combustion pressure rises, combustion completeness, flame speeds, and heat transfer aspects. Comparisons of igniter type and igniter reliability under simulated reactor accident conditions are included. The results of the research programs provide a broad data base covering nearly all aspects of hydrogen combustion related to the performance of deliberate ignition systems

Thermal performance analysis of a direct-expansion solar-assisted heat pump water heater

International Nuclear Information System (INIS)

Kong, X.Q.; Zhang, D.; Li, Y.; Yang, Q.M.

2011-01-01

A direct-expansion solar-assisted heat pump water heater (DX-SAHPWH) is described, which can supply hot water for domestic use during the whole year. The system mainly employs a bare flat-plate collector/evaporator with a surface area of 4.2 m 2 , an electrical rotary-type hermetic compressor, a hot water tank with the volume of 150 L and a thermostatic expansion valve. R-22 is used as working fluid in the system. A simulation model based on lumped and distributed parameter approach is developed to predict the thermal performance of the system. Given the structure parameters, meteorological parameters, time step and final water temperature, the numerical model can output operational parameters, such as heat capacity, system COP and collector efficiency. Comparisons between the simulation results and the experimental measurements show that the model is able to give satisfactory predictions. The effect of various parameters, including solar radiation, ambient temperature, wind speed and compressor speed, has been analyzed on the thermal performance of the system. -- Highlights: ► A direct-expansion solar-assisted heat pump water heater (DX-SAHPWH) is described. ► A simulation model based on lumped and distributed parameter approach is developed to predict the thermal performance of the system. ► The numerical model can output operational parameters, such as heat capacity, system COP and collector efficiency. ► Comparisons between the simulation results and the experimental measurements show that the model is able to give satisfactory predictions. ► The effect of various parameters has been analyzed on the thermal performance of the system.

The economic impact of military expenditures

OpenAIRE

Landau, Daniel

1993-01-01

The author addresses three questions about military spending in developing countries: What are the levels of (and trends in) military spending as a percentage of gross national product? What impact does peacetime military spending have on growth, government spending on social welfare and infrastructure, and other key economic variables? What major factors influence the level of military spending? The author finds that military spending as a share of GNP generally fell in the 1980s, even in th...

Military Versus Civilian Murder-Suicide.

Science.gov (United States)

Patton, Christina L; McNally, Matthew R; Fremouw, William J

2015-07-03

Previous studies have implicated significant differences between military members and civilians with regard to violent behavior, including suicide, domestic violence, and harm to others, but none have examined military murder-suicide. This study sought to determine whether there were meaningful differences between military and civilian murder-suicide perpetrators. Using data from the Center for Disease Control's (CDC) National Violent Death Reporting System (NVDRS), military (n = 259) and civilian (n = 259) murder-suicide perpetrators were compared on a number of demographic, psychological, and contextual factors using chi-square analyses. Logistic regression was used to determine which variables predicted membership to the military or civilian perpetrator groups. Military murder-suicide perpetrators were more likely to be older, have physical health problems, be currently or formerly married, less likely to abuse substances, and to exhibit significantly different motives than civilian perpetrators. Logistic regression revealed that membership to the military, rather than the civilian, perpetrator group was predicted by age, physical health problems, and declining heath motive-reflecting the significance of a more than 15-year difference in mean age between the two groups. Findings point to the need to tailor suicide risk assessments to include questions specific to murder-suicide, to assess attitudes toward murder-suicide, and to the importance of assessing suicide and violence risk in older adult military populations. © The Author(s) 2015.

A set of professional working ability indicators of military operators

Directory of Open Access Journals (Sweden)

Mykola Korchahin

2017-08-01

Full Text Available Purpose: determination of indicators of professional work capacity and their impact on the success of professional activity of military operators in the cycle of alert duty. Material & Methods: indicators of the professional capacity of military operators were determined through theoretical analysis, systematization and generalization of data from scientific and methodological sources, medical-biological, psycho-diagnostic methods and mathematical methods of processing the results of the study. Result: it is determined that the most informative indirect indicators of the professional capacity of military operators of the contract service of the Air Forces of the Armed Forces of Ukraine is: physical condition, psycho-emotional state, physical performance, aerobic endurance, static endurance of back muscles, neck and the abs, the speed of perception, memory, concentration and shifting attention. The correlation dependence of the level of professional preparedness of military operators on indirect indices of professional work capacity: physical fitness (r=0,58, psycho-emotional state (r=0,51, physical performance (r=0,34, aerobic endurance (r=0.59, static endurance of the muscles of the back and neck (r=0,52, static endurance of the abs muscles (r=0,48, simple sensorimotor reaction (r=0,44, short-term (operational memory (r=0,40, concentration and attention switching (r=0,46. Conclusion: a complex characteristic of the indicators of psycho-physiological functions of the body of a specialist can be used to assess the dynamics and prediction of the professional capacity of military operators of the Air Force in the cycle of alert duty.

32 CFR 575.1 - Military Academy.

Science.gov (United States)

2010-07-01

... 32 National Defense 3 2010-07-01 2010-07-01 true Military Academy. 575.1 Section 575.1 National... MILITARY ACADEMY § 575.1 Military Academy. (a) Organization and administration. (1) The United States Military Academy is under the general direction and supervision of the Department of the Army. The...

DHS small-scale safety and thermal testing of improvised explosives-comparison of testing performance

International Nuclear Information System (INIS)

Reynolds, J G; Hsu, P C; Sandstrom, M M; Brown, G W; Warner, K F; Phillips, J J; Shelley, T J; Reyes, J A

2014-01-01

One of the first steps in establishing safe handling procedures for explosives is small-scale safety and thermal (SSST) testing. To better understand the response of improvised materials or homemade explosives (HMEs) to SSST testing, 16 HME materials were compared to three standard military explosives in a proficiency-type round robin study among five laboratories-two DoD and three DOE-sponsored by DHS. The testing matrix has been designed to address problems encountered with improvised materials-powder mixtures, liquid suspensions, partially wetted solids, immiscible liquids, and reactive materials. More than 30 issues have been identified that indicate standard test methods may require modification when applied to HMEs to derive accurate sensitivity assessments needed for developing safe handling and storage practices. This paper presents a generalized comparison of the results among the testing participants, comparison of friction results from BAM (German Bundesanstalt für Materi-alprüfung) and ABL (Allegany Ballistics Laboratory) designed testing equipment, and an overview of the statistical results from the RDX (1,3,5-Trinitroperhydro-1,3,5-triazine) standard tested throughout the proficiency test.

UAV-guided navigation for ground robot tele-operation in a military reconnaissance environment.

Science.gov (United States)

Chen, Jessie Y C

2010-08-01

A military reconnaissance environment was simulated to examine the performance of ground robotics operators who were instructed to utilise streaming video from an unmanned aerial vehicle (UAV) to navigate his/her ground robot to the locations of the targets. The effects of participants' spatial ability on their performance and workload were also investigated. Results showed that participants' overall performance (speed and accuracy) was better when she/he had access to images from larger UAVs with fixed orientations, compared with other UAV conditions (baseline- no UAV, micro air vehicle and UAV with orbiting views). Participants experienced the highest workload when the UAV was orbiting. Those individuals with higher spatial ability performed significantly better and reported less workload than those with lower spatial ability. The results of the current study will further understanding of ground robot operators' target search performance based on streaming video from UAVs. The results will also facilitate the implementation of ground/air robots in military environments and will be useful to the future military system design and training community.

Physiological performance and thermal tolerance of major Red Sea macrophytes

KAUST Repository

Weinzierl, Michael S.

2017-12-01

As anthropogenically-forced ocean temperatures continue to rise, the physiological response of marine macrophytes becomes exceedingly relevant. The Red Sea is a semi-isolated sea- the warmest in the world (SST up to 34°C) - already exhibiting signs of rapid warming rates exceeding those of other tropical oceans. This will have profound effects on the physiology of marine organisms, specifically marine macrophytes, which have direct influence on the dynamic carbonate system of the Red Sea. The aim of this paper is to define the physiological capability and thermal optima and limits of six ecologically important Red Sea macrophytes- ranging from seagrasses to calcifying and non-calcifying algae- and to describe the effects of increasing thermal stress on the performance and limits of each macrophyte in terms of activation energy. Of the species considered, Halophila stipulacae, Halimeda optunia, Halimeda monile and Padina pavonica thrive in thermal extremes and may be more successful in future Red Sea warming scenarios. Specifically, Halimeda opuntia increased productivity and calcification rates up to 38°C, making it the most thermally resilient macrophyte. Halophila stipulacae is the most productive seagrass, and hence has the greatest positive effect on Omega saturation state and offers chemical buffer capacity to future ocean acidification.

THE EUROPEAN UNION MILITARY POWER: THE NEW CHALLENGES WITH OLD DILEMMAS

Directory of Open Access Journals (Sweden)

Blerim Ramadani

2015-09-01

Full Text Available Recent crises show clearly that Europeans security depends on external developments. The Common Security and Defense Policy failed to provide security, while the European Union military missions were limited in terms of their scope. This inability threatens the interests and security of the member states. Exactly, this research explores the concept of military power of the EU. In order to elaborate anatomy of military power of the EU, the descriptive-analytic method is used. Military performance analysis proves that the EU is able to have the greatest impact in the global arena. The research shows that with the achievement of a political strategy among the stakeholder, on which the replacement of the consensus mechanism with an ordinary majority is predicted, the EU would be able to lead a proactive and efficient security policy.

Military deployment and reintegration: a systematic review of child coping.

Science.gov (United States)

Bello-Utu, Cindy F; DeSocio, Janiece E

2015-02-01

Child coping with parent military deployment and family reintegration. A systematic review of research literature was conducted to examine the effects of deployment and family reintegration on children in military families. A search of CINAHL, PubMed, Psyc-INFO, and SocINDEX databases was performed using the terms "military family," "military child," "child coping," "deployment," and "reintegration." The search was limited to publications between 2001 and 2014 to focus on the effects of Operation Enduring Freedom (OEF), Operation Iraqi Freedom (OIF), and Operation New Dawn (OND). Twenty-seven research reports met inclusion criteria. Three themes were extracted: A child's coping is influenced by (a) the child's age and development, (b) the mental health and coping of the non-deployed parent during deployment, and the mental health of both parents during family reintegration, and (c) the pre-existing resilience/vulnerability, cumulative risks, and resources of the child and family. © 2015 Wiley Periodicals, Inc.

Summer Thermal Performance of Ventilated Roofs with Tiled Coverings

International Nuclear Information System (INIS)

Bortoloni, M; Bottarelli, M; Piva, S

2017-01-01

The thermal performance of a ventilated pitched roof with tiled coverings is analysed and compared with unventilated roofs. The analysis is carried out by means of a finite element numerical code, by solving both the fluid and thermal problems in steady-state. A whole one-floor building with a pitched roof is schematized as a 2D computational domain including the air-permeability of tiled covering. Realistic data sets for wind, temperature and solar radiation are used to simulate summer conditions at different times of the day. The results demonstrate that the batten space in pitched roofs is an effective solution for reducing the solar heat gain in summer and thus for achieving better indoor comfort conditions. The efficiency of the ventilation is strictly linked to the external wind conditions and to buoyancy forces occurring due to the heating of the tiles. (paper)

Summer Thermal Performance of Ventilated Roofs with Tiled Coverings

Science.gov (United States)

Bortoloni, M.; Bottarelli, M.; Piva, S.

2017-01-01

The thermal performance of a ventilated pitched roof with tiled coverings is analysed and compared with unventilated roofs. The analysis is carried out by means of a finite element numerical code, by solving both the fluid and thermal problems in steady-state. A whole one-floor building with a pitched roof is schematized as a 2D computational domain including the air-permeability of tiled covering. Realistic data sets for wind, temperature and solar radiation are used to simulate summer conditions at different times of the day. The results demonstrate that the batten space in pitched roofs is an effective solution for reducing the solar heat gain in summer and thus for achieving better indoor comfort conditions. The efficiency of the ventilation is strictly linked to the external wind conditions and to buoyancy forces occurring due to the heating of the tiles.

Military Effectiveness: A Reappraisal

National Research Council Canada - National Science Library

Bernasconi, Jeffrey J

2007-01-01

.... Two divergent theories cover the ground of military effectiveness. One looks at the interaction of social structures, whereas the other looks at the effect organization has on military effectiveness...

Performance analysis of different ORC configurations for thermal energy and LNG cold energy hybrid power generation system

Science.gov (United States)

Sun, Zhixin; Wang, Feng; Wang, Shujia; Xu, Fuquan; Lin, Kui

2017-01-01

This paper presents a thermal energy and Liquefied natural gas (LNG) cold energy hybrid power generation system. Performances of four different Organic Rankine cycle (ORC) configurations (the basic, the regenerative, the reheat and the regenerative-reheat ORCs) are studied based on the first and the second law of thermodynamics. Dry organic fluid R245fa is selected as the typical working fluid. Parameter analysis is also conducted in this paper. The results show that regeneration could not increase the thermal efficiency of the thermal and cold energy hybrid power generation system. ORC with the reheat process could produce more specific net power output but it may also reduce the system thermal efficiency. The basic and the regenerative ORCs produce higher thermal efficiency while the regenerative-reheat ORC performs best in the exergy efficiency. A preheater is necessary for the thermal and cold energy hybrid power generation system. And due to the presence of the preheater, there will be a step change of the system performance as the turbine inlet pressure rises.

Final Design and Experimental Validation of the Thermal Performance of the LHC Lattice Cryostats

International Nuclear Information System (INIS)

Bourcey, N.; Capatina, O.; Parma, V.; Poncet, A.; Rohmig, P.; Serio, L.; Skoczen, B.; Tock, J.-P.; Williams, L. R.

2004-01-01

The recent commissioning and operation of the LHC String 2 have given a first experimental validation of the global thermal performance of the LHC lattice cryostat at nominal cryogenic conditions. The cryostat designed to minimize the heat inleak from ambient temperature, houses under vacuum and thermally protects the cold mass, which contains the LHC twin-aperture superconducting magnets operating at 1.9 K in superfluid helium. Mechanical components linking the cold mass to the vacuum vessel, such as support posts and insulation vacuum barriers are designed with efficient thermalisations for heat interception to minimise heat conduction. Heat inleak by radiation is reduced by employing multilayer insulation (MLI) wrapped around the cold mass and around an aluminium thermal shield cooled to about 60 K.Measurements of the total helium vaporization rate in String 2 gives, after substraction of supplementary heat loads and end effects, an estimate of the total thermal load to a standard LHC cell (107 m) including two Short Straight Sections and six dipole cryomagnets. Temperature sensors installed at critical locations provide a temperature mapping which allows validation of the calculated and estimated thermal performance of the cryostat components, including efficiency of the heat interceptions

Final Design and Experimental Validation of the Thermal Performance of the LHC Lattice Cryostats

Science.gov (United States)

Bourcey, N.; Capatina, O.; Parma, V.; Poncet, A.; Rohmig, P.; Serio, L.; Skoczen, B.; Tock, J.-P.; Williams, L. R.

2004-06-01

The recent commissioning and operation of the LHC String 2 have given a first experimental validation of the global thermal performance of the LHC lattice cryostat at nominal cryogenic conditions. The cryostat designed to minimize the heat inleak from ambient temperature, houses under vacuum and thermally protects the cold mass, which contains the LHC twin-aperture superconducting magnets operating at 1.9 K in superfluid helium. Mechanical components linking the cold mass to the vacuum vessel, such as support posts and insulation vacuum barriers are designed with efficient thermalisations for heat interception to minimise heat conduction. Heat inleak by radiation is reduced by employing multilayer insulation (MLI) wrapped around the cold mass and around an aluminium thermal shield cooled to about 60 K. Measurements of the total helium vaporization rate in String 2 gives, after substraction of supplementary heat loads and end effects, an estimate of the total thermal load to a standard LHC cell (107 m) including two Short Straight Sections and six dipole cryomagnets. Temperature sensors installed at critical locations provide a temperature mapping which allows validation of the calculated and estimated thermal performance of the cryostat components, including efficiency of the heat interceptions.

Study on key technologies of optimization of big data for thermal power plant performance

Science.gov (United States)

Mao, Mingyang; Xiao, Hong

2018-06-01

Thermal power generation accounts for 70% of China's power generation, the pollutants accounted for 40% of the same kind of emissions, thermal power efficiency optimization needs to monitor and understand the whole process of coal combustion and pollutant migration, power system performance data show explosive growth trend, The purpose is to study the integration of numerical simulation of big data technology, the development of thermal power plant efficiency data optimization platform and nitrogen oxide emission reduction system for the thermal power plant to improve efficiency, energy saving and emission reduction to provide reliable technical support. The method is big data technology represented by "multi-source heterogeneous data integration", "large data distributed storage" and "high-performance real-time and off-line computing", can greatly enhance the energy consumption capacity of thermal power plants and the level of intelligent decision-making, and then use the data mining algorithm to establish the boiler combustion mathematical model, mining power plant boiler efficiency data, combined with numerical simulation technology to find the boiler combustion and pollutant generation rules and combustion parameters of boiler combustion and pollutant generation Influence. The result is to optimize the boiler combustion parameters, which can achieve energy saving.

Thermal storage/discharge performances of Cu-Si alloy for solar thermochemical process

Science.gov (United States)

Gokon, Nobuyuki; Yamaguchi, Tomoya; Cho, Hyun-seok; Bellan, Selvan; Hatamachi, Tsuyoshi; Kodama, Tatsuya

2017-06-01

The present authors (Niigata University, Japan) have developed a tubular reactor system using novel "double-walled" reactor/receiver tubes with carbonate molten-salt thermal storage as a phase change material (PCM) for solar reforming of natural gas and with Al-Si alloy thermal storage as a PCM for solar air receiver to produce high-temperature air. For both of the cases, the high heat capacity and large latent heat (heat of solidification) of the PCM phase circumvents the rapid temperature change of the reactor/receiver tubes at high temperatures under variable and uncontinuous characteristics of solar radiation. In this study, we examined cyclic properties of thermal storage/discharge for Cu-Si alloy in air stream in order to evaluate a potentiality of Cu-Si alloy as a PCM thermal storage material. Temperature-increasing performances of Cu-Si alloy are measured during thermal storage (or heat-charge) mode and during cooling (or heat-discharge) mode. A oxidation state of the Cu-Si alloy after the cyclic reaction was evaluated by using electron probe micro analyzer (EPMA).

MILITARY LEADERSHIP VISION

Directory of Open Access Journals (Sweden)

Gheorghe CALOPĂREANU

2013-12-01

Full Text Available The actual study is aimed at defining the place and the role of the concepts of authority, management and leadership and their connexions within the recognized military strategic systems. In addition to the above mentioned main objective, the following related aims will be achieved in the present work: - to analyze the command, management and leadership nexus; - to make suggestions for configuring an effective professional framework to address the armed forces leadership challenges and the visionary leader concept. Eventually, the present study will emphasize the need for the military leaders to lead not only the members of the organization but the military organizations themselves.

Experimental investigation on the thermal performance of a closed oscillating heat pipe in thermal management

Science.gov (United States)

Rao, Zhonghao; Wang, Qingchao; Zhao, Jiateng; Huang, Congliang

2017-10-01

To investigate the thermal performance of the closed oscillating heat pipe (OHP) as a passive heat transfer device in thermal management system, the gravitation force, surface tension, cooling section position and inclination angle were discussed with applied heating power ranging from 5 to 65 W. The deionized water was chosen as the working fluid and liquid-filling ratio was 50 ± 5%. The operation of the OHP mainly depends on the phase change of the working fluid. The working fluid within the OHP was constantly evaporated and cooled. The results show that the movement of the working fluid was similar to the forced damped mechanical vibration, it has to overcome the capillary resistance force and the stable oscillation should be that the OHP could successful startup. The oscillation frequency slowed and oscillation amplitude decreased when the inclination angle of the OHP increased. However, the thermal resistance increased. With the increment of the heating power, the average temperature of the evaporation and condensation section would be close. If the heating power was further increased, dry-out phenomenon within the OHP would appeared. With the decrement of the L, the start-up heating power also decreased and stable oscillation would be formed.

Thermal performance comparison of oscillating heat pipes with and without helical micro-grooves

Science.gov (United States)

Qu, Jian; Li, Xiaojun; Xu, Qian; Wang, Qian

2017-11-01

This paper presents an experimental investigation to compare the thermal performance of three closed loop oscillating heat pipes (OHPs) with and without internal helical microgrooves at vertical and horizontal orientations. All of these OHPs were made from copper tubes and have three turns with lengths of 70, 230 and 110 mm at the evaporator, adiabatic and condenser sections, respectively. Deionized water was used as the working fluid at a volumetric filling ratio of 50%. The internal diameters (IDs) of two smooth-tube OHPs are 4.0 and 4.8 mm, respectively, and the internal diameter of micro-grooved OHP without groove structures is about 4.5 mm. Experimental results demonstrated that the addition of groove structures make the OHP remarkably outperform smooth-tube OHPs in both effective thermal conductivity and thermal resistance. The thermal resistance of vertically-oriented micro-grooved OHP could be lowered to 0.057 °C/W associated with an effective thermal conductivity of 6.1 × 104 W/ (m·K) at the input heat flux of 3.8 × 104 W/m2. Compared to smooth-tube OHPs, preliminary mechanism analysis reveals that local heat transfer coefficients both at the heating and cooling sections of micro-grooved OHP could be significantly improved. Moreover, enhanced liquid backflow to the evaporator due to microgroove-induced capillarity is also responsible for the OHP performance enhancement.

KUGEL: a thermal, hydraulic, fuel performance, and gaseous fission product release code for pebble bed reactor core analysis

International Nuclear Information System (INIS)

Shamasundar, B.I.; Fehrenbach, M.E.

1981-05-01

The KUGEL computer code is designed to perform thermal/hydraulic analysis and coated-fuel particle performance calculations for axisymmetric pebble bed reactor (PBR) cores. This computer code was developed as part of a Department of Energy (DOE)-funded study designed to verify the published core performance data on PBRs. The KUGEL code is designed to interface directly with the 2DB code, a two-dimensional neutron diffusion code, to obtain distributions of thermal power, fission rate, fuel burnup, and fast neutron fluence, which are needed for thermal/hydraulic and fuel performance calculations. The code is variably dimensioned so that problem size can be easily varied. An interpolation routine allows variable mesh size to be used between the 2DB output and the two-dimensional thermal/hydraulic calculations

Numerical Simulation of Thermal Performance of Glass-Fibre-Reinforced Polymer

Science.gov (United States)

Zhao, Yuchao; Jiang, Xu; Zhang, Qilin; Wang, Qi

2017-10-01

Glass-Fibre-Reinforced Polymer (GFRP), as a developing construction material, has a rapidly increasing application in civil engineering especially bridge engineering area these years, mainly used as decorating materials and reinforcing bars for now. Compared with traditional construction material, these kinds of composite material have obvious advantages such as high strength, low density, resistance to corrosion and ease of processing. There are different processing methods to form members, such as pultrusion and resin transfer moulding (RTM) methods, which process into desired shape directly through raw material; meanwhile, GFRP, as a polymer composite, possesses several particular physical and mechanical properties, and the thermal property is one of them. The matrix material, polymer, performs special after heated and endue these composite material a potential hot processing property, but also a poor fire resistance. This paper focuses on thermal performance of GFRP as panels and corresponding researches are conducted. First, dynamic thermomechanical analysis (DMA) experiment is conducted to obtain the glass transition temperature (Tg) of the object GFRP, and the curve of bending elastic modulus with temperature is calculated according to the experimental data. Then compute and estimate the values of other various thermal parameters through DMA experiment and other literatures, and conduct numerical simulation under two condition respectively: (1) the heat transfer process of GFRP panel in which the panel would be heated directly on the surface above Tg, and the hot processing under this temperature field; (2) physical and mechanical performance of GFRP panel under fire condition. Condition (1) is mainly used to guide the development of high temperature processing equipment, and condition (2) indicates that GFRP’s performance under fire is unsatisfactory, measures must be taken when being adopted. Since composite materials’ properties differ from each other

The Ambiguity of Foreign Military Assistance

DEFF Research Database (Denmark)

Laugesen, Henrik

This study tests the argument that Foreign Military Assistance and the consequently professionalizing of the recipient military has a positive effect on the process of democratization in Kenya.......This study tests the argument that Foreign Military Assistance and the consequently professionalizing of the recipient military has a positive effect on the process of democratization in Kenya....

What is the best clothing to prevent heat and cold stress? Experiences with thermal manikin.

Science.gov (United States)

Magyar, Z; Tamas, R

2013-02-01

The present study summarizes the current knowledge of the heat and cold stress which might significantly affect military activities and might also occur among travellers who are not well adapted to weather variations during their journey. The selection of the best clothing is a very important factor in preserving thermal comfort. Our experiences with thermal manikin are also represented in this paper.

Thermal performance analysis of reciprocating compressor with stepless capacity control system

International Nuclear Information System (INIS)

Bin, Tang; Yuanyang, Zhao; Liansheng, Li; Guangbin, Liu; Le, Wang; Qichao, Yang; Haiping, Xu; Feng, Zhu; Wenhui, Meng

2013-01-01

On the basic principle of stepless capacity control system for large reciprocating compressor, the thermal cycle was analyzed. The equations for the process of suction, reverse flow, compression, discharge and expansion of clearance gas were established. According to these equations, p–V diagrams at various situations were simulated. An experimental platform was setup and the compressor with designed stepless capacity control system run well. The experimental results show that the capacity of compressor can be regulated steplessly, and the motor power is reduced proportionally with respect to the reduction of capacity. During the suction process, both the flow resistance of valve and the pressure fluctuation in cylinder can be reduced by opening the suction valves with the actuators. The simulated and experimental results showed good coincidence. The clearance volume and valve clearance Mach number had a negative influence on the thermal performance of compressor with stepless capacity control system. -- Highlights: ► Flow resistance of valve can be reduced and pressure fluctuation can be reduced. ► Equivalent Mach number of reverse flow is much higher than that of suction process. ► Response of stepless capacity control system is important for regulation accuracy. ► Clearance and valve clearance Mach number have influence on thermal performance

National Military Family Association

Science.gov (United States)

... MilitaryFamily.org © 2017 - National Military Family Association Twitter Facebook Pinterest Instagram Charity Navigator Four Star Charity GuideStar Exchange Better Business Bureau Charity Watch Independent Charity of America nonprofit ...

Thermal Performance Analysis of a Geologic Borehole Repository

Energy Technology Data Exchange (ETDEWEB)

Reagin, Lauren [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-08-16

The Brazilian Nuclear Research Institute (IPEN) proposed a design for the disposal of Disused Sealed Radioactive Sources (DSRS) based on the IAEA Borehole Disposal of Sealed Radioactive Sources (BOSS) design that would allow the entirety of Brazil’s inventory of DSRS to be disposed in a single borehole. The proposed IPEN design allows for 170 waste packages (WPs) containing DSRS (such as Co-60 and Cs-137) to be stacked on top of each other inside the borehole. The primary objective of this work was to evaluate the thermal performance of a conservative approach to the IPEN proposal with the equivalent of two WPs and two different inside configurations using Co-60 as the radioactive heat source. The current WP configuration (heterogeneous) for the IPEN proposal has 60% of the WP volume being occupied by a nuclear radioactive heat source and the remaining 40% as vacant space. The second configuration (homogeneous) considered for this project was a homogeneous case where 100% of the WP volume was occupied by a nuclear radioactive heat source. The computational models for the thermal analyses of the WP configurations with the Co-60 heat source considered three different cooling mechanisms (conduction, radiation, and convection) and the effect of mesh size on the results from the thermal analysis. The results of the analyses yielded maximum temperatures inside the WPs for both of the WP configurations and various mesh sizes. The heterogeneous WP considered the cooling mechanisms of conduction, convection, and radiation. The temperature results from the heterogeneous WP analysis suggest that the model is cooled predominantly by conduction with effect of radiation and natural convection on cooling being negligible. From the thermal analysis comparing the two WP configurations, the results suggest that either WP configuration could be used for the design. The mesh sensitivity results verify the meshes used, and results obtained from the thermal analyses were close to

Military experience can influence Women's eating habits.

Science.gov (United States)

Breland, Jessica Y; Donalson, Rosemary; Nevedal, Andrea; Dinh, Julie V; Maguen, Shira

2017-11-01

Disordered eating, ranging from occasional binge eating or restriction to behaviors associated with eating disorder diagnoses, is common among military personnel and veterans. However, there is little information on how military service affects eating habits. To describe possible pathways between military service and disordered eating among women veterans, a high risk group. Twenty women veterans who reported changing eating habits in response to stress participated in audio-recorded focus groups or dyadic interviews between April 2013 and October 2014. We used thematic analysis of transcripts to identify and understand women's self-reported eating habits before, during, and after military service. Participants reported entering the military with varied eating habits, but little disordered eating. Participants described several ways military environments affected eating habits, for example, by promoting fast, irregular, binge-like eating and disrupting the reward value of food. Participants believed military-related stressors, which were often related to gender, also affected eating habits. Such stressors included military sexual trauma and the need to meet military weight requirements in general and after giving birth. Participants also reported that poor eating habits continued after military service, often because they remained under stress. For some women, military service can result in socialization to poor eating habits, which when combined with exposure to stressors can lead to disordered eating. Additional research is needed, including work to understand possible benefits associated with providing support in relation to military weight requirements and the transition out of military service. Given the unique experiences of women in the military, future work could also focus on health services surrounding pregnancy-related weight change and the stress associated with being a woman in predominantly male military environments. Published by Elsevier Ltd.

New business with the new military.

Science.gov (United States)

Apgar, Mahlon; Keane, John M

2004-09-01

A $200 billion market has appeared on your business horizon, but you may not have noticed it. It's the U.S. military--the new U.S. military. Virtually all aspects of the military are changing to ensure it can fight unpredictable threats while sustaining the infrastructure needed to support and train forces. The military is turning to non-traditional business partners to meet a wide range of needs, from health care to housing to information technology. The Defense Department is yielding its monopoly on every aspect of national security and adopting a more businesslike model in which the military's warfighting capabilities are supported through outsourcing and business alliances. Civilians are replacing military personnel in many noncombat roles. Military functions with corporate equivalents are candidates for outsourcing and privatization. Market standards are replacing the heavy customization that has locked many companies out of this marketplace. The authors have participated in the transformation process from different perspectives--one civilian, the other military. Together, they highlight the prospects that transformation is creating for companies outside the traditional defense industry and reveal paths to success in this complex market. They also present six principles for doing business with the military that require persistence, integrity, and a willingness to master the intricacies of a distinctive culture. By understanding the logic of military transformation, executives can identify and create vast new business opportunities. And by mastering the six principles, they can build profitable long-term relationships.

Thermal performance parameters estimation of hot box type solar cooker by using artificial neural network

Energy Technology Data Exchange (ETDEWEB)

Kurt, Hueseyin; Atik, Kemal; Oezkaymak, Mehmet; Recebli, Ziyaddin [Zonguldak Karaelmas University, Karabuk Technical Education Faculty, 78200 Karabuk (Turkey)

2008-02-15

Work to date has shown that Artificial Neural Network (ANN) has not been used for predicting thermal performance parameters of a solar cooker. The objective of this study is to predict thermal performance parameters such as absorber plate, enclosure air and pot water temperatures of the experimentally investigated box type solar cooker by using the ANN. Data set is obtained from the box type solar cooker which was tested under various experimental conditions. A feed-forward neural network based on back propagation algorithm was developed to predict the thermal performance of solar cooker with and without reflector. Mathematical formulations derived from the ANN model are presented for each predicting temperatures. The experimental data set consists of 126 values. These were divided into two groups, of which the 96 values were used for training/learning of the network and the rest of the data (30 values) for testing/validation of the network performance. The performance of the ANN predictions was evaluated by comparing the prediction results with the experimental results. The results showed a good regression analysis with the correlation coefficients in the range of 0.9950-0.9987 and mean relative errors (MREs) in the range of 3.925-7.040% for the test data set. The regression coefficients indicated that the ANN model can successfully be used for the prediction of the thermal performance parameters of a box type solar cooker with a high degree of accuracy. (author)

Military Classics

Science.gov (United States)

1988-01-01

the relation of religion and politics to seventeenth-century English military history. Frederick II, King of Prussia. Frederick the Great on the Art...Beginning with the reign of King Henry VIII, Barnett’s work explores the history of the British Army as an institution and fighting force. The volume...native clans led by Shaka , to its fall under the guns of the British Army by 1878. The Zulus produced a formidable military force, and this excellent

[Stress at work among military doctors: a preliminary study].

Science.gov (United States)

Knezević, Bojana; Belosević, Ljiljana

2006-09-01

/14), lack of appropriate continuing education (10/14) and trouble with superiors (9/14) were predominantly reported by military general practitioners. Our preliminary study has suggested that military physicians, especially military general practitioners, recognize more stressors and at higher frequency than civilian physicians. The ten leading stressors reported by the two study groups differed, however, both groups reported inadequate salary, poor resources, poor management and unpredictable situations among the first ten. Many studies tackling occupational stress in physicians, suggest that they are at risk of work stress. Several studies have found job stress to be a significant source of distress for military personnel during peacetime assignment. However, to our knowledge, no studies on work stress in military physicians have been published. Some of the most important stressors identified by our military physicians, such as poor resources, poor management, excessive paperwork, unpredictable situations and 24-hour standby are well known stressors the physicians are dealing with. Compared with studies on work stress in military personnel, our group more frequently reported inadequate salary, being bypassed to promotion, poor communication and trouble with their superiors. Our preliminary results suggest that military physicians recognize different stressors and to a greater extent than civilian physicians. The reported stressors suggest specific professional environment of military physicians. Stress at work needs careful and thorough consideration, not only because it can cause health problems and emotional suffering in military physicians, but also because it can diminish the quality of medical care that they are expected to provide. The stressors that are remediable should be identified and the job stress reduction procedures should be performed.

Thermal remote sensing approach combined with field spectroscopy for detecting underground structures intended for defence and security purposes in Cyprus

Science.gov (United States)

Melillos, George; Themistocleous, Kyriacos; Hadjimitsis, Diofantos G.

2018-04-01

The purpose of this paper is to present the results obtained from unmanned aerial vehicle (UAV) using multispectral with thermal imaging sensors and field spectroscopy campaigns for detecting underground structures. Airborne thermal prospecting is based on the principle that there is a fundamental difference between the thermal characteristics of underground structures and the environment in which they are structure. This study aims to combine the flexibility and low cost of using an airborne drone with the accuracy of the registration of a thermal digital camera. This combination allows the use of thermal prospection for underground structures detection at low altitude with high-resolution information. In addition vegetation indices such as the Normalized Difference Vegetation Index (NDVI) and Simple Ratio (SR), were utilized for the development of a vegetation index-based procedure aiming at the detection of underground military structures by using existing vegetation indices or other in-band algorithms. The measurements were taken at the following test areas such as: (a) vegetation area covered with the vegetation (barley), in the presence of an underground military structure (b) vegetation area covered with the vegetation (barley), in the absence of an underground military structure. It is important to highlight that this research is undertaken at the ERATOSTHENES Research Centre which received funding to be transformed to an EXcellence Research Centre for Earth SurveiLlance and Space-Based MonItoring Of the EnviRonment (Excelsior) from the HORIZON 2020 Widespread-04-2017: Teaming Phase 1(Grant agreement no: 763643).

A novel louvered fin design to enhance thermal and drainage performances during periodic frosting/defrosting conditions

International Nuclear Information System (INIS)

Kim, Min-Hwan; Kim, Hisuk; Kim, Dong Rip; Lee, Kwan-Soo

2016-01-01

Highlights: • Thermal and drainage performances of a novel design louvered fin were investigated. • The thermal performance of the asymmetric fin was improved in the re-frosting cycle. • The asymmetric louvered fin exhibited better drainage on the leading edge of fins. • Lower surface tension between fin surface and water droplet improved the drainage. - Abstract: The retention water on fin surface can significantly degrade the thermal performance of heat exchangers under periodic frosting/defrosting conditions, which also leads to a decrease in the energy efficiency of air-source heat pumps. A novel louvered fin design was suggested to improve the drainage and the thermal performance of heat exchanger. The novel louvered fin had an asymmetric louver arrangement by flattening two louvers on the leading edge. The retention water formed on fin surface markedly decreased the heat transfer rate of the conventional symmetric louvered fins in re-frosting cycles. On the other hand, the asymmetric louvered fins improved the drainage performance of the retention water, which enhanced the heat transfer rate. To identify the reason of the difference in drainage performance between two fin geometries, additional experiments were carried out with enlargement models. The improvement in drainage performance of the asymmetric fin design originated from the lowered surface tension between the fin surface and water droplet.

Thermal performance of small solar domestic hot water systems in theory, in the laboratory and in practice

DEFF Research Database (Denmark)

Andersen, Elsa

1998-01-01

for poor thermal performances of systems tested in practice are given. Based on theoretical calculations the negative impact on the thermal performance, due to a large number of different parameter variations are given. Recommendations for future developments of small solar domestic hot water systems...

Determination of cordycepin content of Cordyceps militaris ...

African Journals Online (AJOL)

Determination of cordycepin content of Cordyceps militaris recombinant rice by high performance liquid chromatography. ... Relative standard deviation (RSD), precision and repeatability RSD was 2.38, 0.76 and 1.46 %, respectively. Conclusion: The HPLC method is simple, fast, accurate and reproducible. It is suitable for ...

Status Configurations, Military Service and Higher Education

Science.gov (United States)

Wang, Lin; Elder, Glen H., Jr.; Spence, Naomi J.

2012-01-01

The U.S. Armed Forces offer educational and training benefits as incentives for service. This study investigates the influence of status configurations on military enlistment and their link to greater educational opportunity. Three statuses (socioeconomic status of origin, cognitive ability and academic performance) have particular relevance for…

Problems of Military Cemeteries Greenery - Case Study of the Military Cemetery in Zvolen

Science.gov (United States)

Halajová, Denisa; Petreková, Denisa; Bihuňová, Mária

2017-10-01

The intention of this work is to highlight the importance of understanding military cemeteries as objects of cultural and historical heritage and as a part of garden design history. The design and maintenance of cemeteries and graves is a manifestation of the national culture. This is even more evident in military cemeteries, the maintenance of which is regulated by international agreements. Objects of military cemeteries are important places not only from the historical and architectural point of view, but also as green space. Most military cemeteries in Slovakia originated from World War I and II. In Slovakia, 160,000 soldiers were buried, 75,206 of them lost their lives in World War I and 93,000 in World War II. 32,495 war graves are registered by The Ministry of the Interior of the Slovak Republic - 23,316 war graves from World War I and 9,179 from World War II. From the period of World War II, there are 22 cemeteries and graveyards in Slovakia, established for soldiers of the Soviet, German, Romanian and Czechoslovak army. Military cemeteries and memorials are mostly high quality works of architecture and art. This paper focuses on the current situation and restoration issues of military cemeteries by examining the Military Cemetery in Zvolen. In the context of its planned reconstruction, a comprehensive tree assessment has been started in 2016. The Military Cemetery in Zvolen, being one of the largest military cemeteries in Slovakia, consists of The Cemetery of the Soviet Army with 17,628 buried soldiers and The Romanian Cemetery with 11,000 buried soldiers. The Romanian Cemetery is one of the largest cemeteries of the Romanian Army in Europe. Both cemeteries were declared national cultural monuments in 1963. In the cemetery, dendrometrical parameters and the health condition of trees were evaluated. In total, there are 825 woody plants. In both cemeteries, coniferous trees prevail, mainly individuals of the genus Thuja (49.4 %). Moreover, the maintenance of

A brief introduction to the military workplace culture.

Science.gov (United States)

Redmond, S A; Wilcox, S L; Campbell, S; Kim, A; Finney, K; Barr, K; Hassan, A M

2015-01-01

Military culture and workplace are areas of interest for researchers across disciplines. However, few publications on military culture exist. The purpose of this article is to introduce general concepts regarding the structure and culture of the United States Military and discuss how this creates challenges for reintegrating into the civilian world. Topics that will be covered in this article include an overview of the Department of Defense (DoD) and Department of Veterans Affairs (VA), socialization to military culture, the unique features of the military as a workplace, the cultural experiences of military personnel reintegrating back into the community, and the challenges faced by military members and their spouses. The provided information on military culture will expand military cultural competency so that civilian employers can enhance their ability to create supportive workplaces for veterans and military spouses during times of transition and reintegration. The unique characteristics of the military culture should be understood by those who work with or plan to work with military populations.