• Title/Summary/Keyword: Extreme temperature

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The Trends and Outlook of Technology Development for Oil and Gas in the Arctic (북극 석유·천연가스 자원 기술개발 현황 및 전망)

  • Lim, Jong-Se;Shin, Hyo-Jin;Kim, Ji-Su;Jin, Young-Keun
    • Ocean and Polar Research
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    • v.36 no.3
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    • pp.303-318
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    • 2014
  • The rising global demand for energy resources may lead to greater interest in the Arctic region. Since it has various resources, such as oil and gas, and large potential as a strategic location in exploration and production (E&P), there is likely to occur island sovereignty issues between the five arctic costal states and other countries. While global warming has led to the opening of the Northeast Passage and the Northwest Passage, several obstacles may impede the development of this area such as the low temperature environment, infrastructure problems in a limited area, flow assurance, environmental regulations, etc. To overcome these problems, various techniques have been applied in the exploration, development, production, transportation, and environment fields and it seems to be made technical development in extreme environment. In this study, the E&P status of representative states and development technologies in the Arctic region have been summarized with regard to carrying out E&P related to drilling, development, production, and operation in oil and gas fields. Furthermore, environmental factors have been taken into account to enhance progress with regard to E&P and ensure sustainable development in the Arctic. On that basis, it will be possible to secure oil and gas field development, production technology and R&D infrastructure in the Arctic.

Analytical Investigation of In-direct Heater to Simulate Space Thermal Environment for Thermal Vacuum Test (열진공 시험용 비접촉식 우주 열환경 모사 장치의 해석적 검토)

  • Baek, Cheul-Woo;Shin, So-Min;Oh, Hyun-Ung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.2
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    • pp.178-183
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    • 2012
  • To simulate space thermal environment in thermal vacuum test, direct or in-direct heater has been applied on the radiator. Both of them, direct heater attached on the radiator and indirect heater with a distance from the radiator, simulate the heat fluxes from the Sun radiation, the Earth IR and Albedo. They also supply the heat fluxes to the radiator of spacecraft to achieve the target temperature according to thermal test conditions. In general, indirect heater is used when the heater is not allowed to attach on the radiator directly due to constraints of coating property or contamination. For in-direct heater design, it is needed to estimate the heat power to make the extreme test conditions and minimize the interference with heat exchange of radiator and shroud. In this study, optimized thermal design of in-direct heater is proposed and investigated by commercial S/W SINDA. The effective values of design factors are also derived.

DESIGN OF CAMERA CONTROLLER FOR HIGH RESOLUTION SPACE-BORN CAMERA SYSTEM

  • Heo, Haeng-Pal;Kong, Jong-Pil;Kim, Young-Sun;Park, Jong-Euk;Yong, Sang-Soon
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.130-133
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    • 2007
  • In order to get high quality and high resolution image data from the space-borne camera system, the image chain from the sensor to the user in the ground-station need to be designed and controlled with extreme care. The behavior of the camera system needs to be controlled by ground commands to support on-orbit calibration and to adjust imaging parameters and to perform early stage on-orbit image correction, like gain and offset control, non-uniformity correction, etc. The operation status including the temperature of the sensor needs to be transferred to the ground-station. The preparation time of the camera system for imaging with specific parameters should be minimized. The camera controller needs to synchronize the operation of cameras for every channel and for every spectral band. Detail timing information of the image data needs to be provided for image data correction at ground-station. In this paper, the design of the camera controller for the AEISS on KOMPSAT-3 will be introduced. It will be described how the image chain is controlled and which imaging parameters are to be adjusted The camera controller will have software for the flexible operation of the camera by the ground-station operators and it can be reconfigured by ground commands. A simple concept of the camera operations and the design of the camera controller, not only with hardware but also with controller software are to be introduced in this paper.

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Impact of Climate Change on Water Cycle and Soil Loss in Daecheong Reservoir Watershed (기후변화에 따른 대청호 유역의 물 순환 및 토양 유실량 영향)

  • Ye, Lyeong;Chung, Se Woong;Oh, Dong Geun;Yoon, Sung Wan
    • Journal of Korean Society on Water Environment
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    • v.25 no.6
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    • pp.821-831
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    • 2009
  • The study was aimed to assess the expected impact of climate change on the water cycle and soil losses in Daecheong Reservoir watershed, Korea using the Soil and Water Assessment Tool (SWAT) that was validated for the watershed in a previous study. Future climate data including precipitation, temperature and humidity generated by introducing a regional climate model (Mesoscale Model Version 5, MM5) to dynamically downscale global circulation model (European Centre Hamburg Model Version 4, ECHAM4) were used to simulate the hydrological responses and soil erosion processes in the future 100 years (2001~2100) under the Special Report on Emissions Scenario (SRES) A1B. The results indicated that the climate change may increase in the amount of surface runoff and thereby sediment load to the reservoir. Spatially, the impact was relatively more significant in the subbasin Bocheongcheon because of its lower occupation rate of forest land compared to other subbasins. Seasonally, the increase of surface runoff and soil losses was more significant during late summer and fall season when both flood control and turbidity flow control are necessary for the reservoir and downstream. The occurrence of extreme turbidity flow events during these period is more vulnerable to reservoir operation because the suspended solids that remained water column can be resuspended by vertical mixing during winter turnover period. The study results provide useful information for the development of adaptive management strategy for the reservoir to cope with the expected impact of future climate change.

Cold Hardiness in Relation to Vine Management in 'Campbell Early' Grapevines ('캠벨얼리' 포도의 수체관리와 내한성)

  • Song, Gi-Cheol;Choi, In-Myung;Cho, Myong-Dong
    • Horticultural Science & Technology
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    • v.18 no.3
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    • pp.387-390
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    • 2000
  • The experiment was conducted to investigate the effects of vine management and yield on fruit quality and bud burst of 'Campbell Early' grapevines in Hwaseong and Suwon area. The extreme value of minimum temperature of Hwaseong area, frequently causing cold damage, was lower than that of Suwon area in winter. Narrow spacing, overbearing, and poor vine management were observed in Hwaseong area, where the harvest time was delayed by 7 days compared with that of Suwon area. Total carbohydrate content of bearing mother branches was lower with 1.2~1.7%, and the percentage of bud burst was extremely lower at $-15^{\circ}C$. In Suwon area, there were no differences in cluster and berry size, but soluble solids content was lower and skin coloration was poorer when yield was high. Total carbohydrate content was lower when yield was high. The percentage of bud burst was lower at cold treatments below $-20^{\circ}C$. The results suggest that appropriate yield based on fruit quality is 2.3~2.6 MT/10a.

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Thermal Design and Analysis for Space Imaging Sensor on LEO (지구 저궤도에서 운용되는 영상센서를 위한 열설계 및 열해석)

  • Shin, So-Min;Oh, Hyun-Ung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.39 no.5
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    • pp.474-480
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    • 2011
  • Space Imaging Sensor operated on LEO is affected from the Earth IR and Albedo as well as the Sun Radiation. The Imaging Sensor exposed to extreme environment needs thermal control subsystem to be maintained in operating/non-operating allowable temperature. Generally, units are periodically dissipated on spacecraft panel, which is designed as radiator. Because thermal design of the imaging sensor inside a spacecraft is isolated, heat pipes connected to radiators on the panel efficiently transfer dissipation of the units. First of all, preliminary thermal design of radiating area and heater power is performed through steady energy balance equation. Based on preliminary thermal design, on-orbit thermal analysis is calculated by SINDA, so calculation for thermal design could be easy and rapid. Radiators are designed to rib-type in order to maintain radiating performance and reduce mass. After on-orbit thermal analysis, thermal requirements for Space Imaging Sensor are verified.

Formation of Salty Materials on Granite Surface by Environmental Pollutants - Effects of TiO2 - (환경오염물질에 의한 화강암 표면에서의 염의 생성에 관한 연구 - TiO2의 영향을 중심으로 -)

  • Shon, Byung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.5
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    • pp.1754-1759
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    • 2010
  • Because the stone cultural properties located outdoors, they have been altered and deteriorated in external appearance due to environmental factors such as acid rain, extreme change in temperature, and salts. Damage to stone cultural properties is accelerated particularly due to recent industrial development and environmental pollution. An experimental study was conducted to evaluate the effect of environmental contaminants(sea water and air pollutants such as, $SO_2$, NO, $CO_2$) on the weathering of granite. And as part of the developing of conservation method, $TiO_2$ catalyst was prepared and tested. After expose a granite to sea water and air pollutants, the mineral compositions of the tested granite surface were lower then that of the fresh granite. And absorption capacity of the weathered granite was steadily increased. From these results, it was expected that granite could be weathered by sea water and air pollutants. For the $TiO_2$ coated granite, absorption capacity was slightly enhanced compared to the $TiO_2$ non-coated granite. Therefore, the $TiO_2$ coating method tested in this study considered to be a viable method to assist in the conservation of granite from environmental contaminants.

The Effect of Climate Change on Water Quality Analysis in a Dam River Basin (기후변화시나리오에 따른 댐유역의 장기 수질변화 예측)

  • Jung, Je Ho;Kim, Dong Il;Choi, Hyun Gu;Han, Kun Yeun
    • Journal of Environmental Impact Assessment
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    • v.20 no.2
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    • pp.107-121
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    • 2011
  • To assess the impact of climate change on water quality in an impounded river basin, this study estimated future air temperature and rainfall in the years of 2020, 2050 and 2080 by statistically downscaling the simulation results from two GCM models combined with two emission scenarios (A2 and B1). Both scenarios were selected from the Special Report on Emission Scenarios (SRES) suggested by IPCC. The A2 scenario represents an extreme condition whereas the B1 scenario represents a clean and energy efficient condition which is similar to that of study basin. With the results of estimated climate factors and land use data, the discharge and the concentrations of BOD, TN and TP in the Andong dam basins were simulated using the SWAT model. The change in BOD concentration for the B1 emission scenario was greater than the A2 scenario in the annual increase range and the pollution level. The concentration of TN was decreased during March? June which is drought period and increased again afterward. In contrast to TN, the concentration of TP was generally decreased. The change in TP concentration was greater for the B1 scenario than the A2 scenario.

Extraordinary Magnetomechanical Coupling as a Result of a Combined Magnetic Structural Transition in a New Class of Rare Earth Compound

  • Jiles, D.C.;Lee, S.J.;Han, M.;Lo, C.C.H.;Snyder, J.E.;Gschneidner, K.A.;Pecharsky, V.K.;Pecharsky, A.O.;Lograsso, T.;Schlagel, D.
    • Journal of Magnetics
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    • v.8 no.1
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    • pp.1-6
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    • 2003
  • The new class of $Gd_5(Si_xGe_{1-x})_4$ compounds undergoes a simultaneous magnetic/structural phase transition giving a high level of strain that can be induced either by change in temperature or by application of a magnetic field. Profound changes of structural, magnetic, and electronic changes occur in the $Gd_5(Si_xGe_{1-x})_4$ system lead to extreme behavior of the material such as the giant magnetocaloric effect, colossal magnetostriction, and giant magnetoresistance. These unique material characters can be utilized for various applications including magnetic solid refrigerants, sensors, and actuators.

Profiling of Recovery Efficiencies for Three Standard Protocols (FDA-BAM, ISO-11290, and Modified USDA) on Temperature-Injured Listeria monocytogenes

  • Lee, Hai Yen;Chai, Lay Ching;Pui, Chai Fung;Wong, Woan Chwen;Mustafa, Shuhaimi;Cheah, Yoke Kqueen;Issa, Zuraini Mat;Nishibuchi, Mitsuaki;Radu, Son
    • Journal of Microbiology and Biotechnology
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    • v.21 no.9
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    • pp.954-959
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    • 2011
  • There have been a number of studies conducted in order to compare the efficiencies of recovery rates, utilizing different protocols, for the isolation of L. monocytogenes. However, the severity of multiple cell injury has not been included in these studies. In the current study, L. monocytogenes ATCC 19112 was injured by exposure to extreme temperatures ($60^{\circ}C$ and $-20^{\circ}C$) for a one-step injury, and for a two-step injury the cells were transferred directly from a heat treatment to frozen state to induce a severe cell injury (up to 100% injury). The injured cells were then subjected to the US Food and Drug Administration (FDA), the ISO-11290, and the modified United States Department of Agriculture (mUSDA) protocols, and plated on TSAyeast (0.6% yeast), PALCAM agar, and CHROMAgar Listeria for 24 h or 48 h. The evaluation of the total recovery of injured cells was also calculated based on the costs involved in the preparation of media for each protocol. Results indicate that the mUSDA method is best able to aid the recovery of heat-injured, freeze-injured, and heat-freeze-injured cells and was shown to be the most cost effective for heat-freeze-injured cells.