• Title/Summary/Keyword: Sources of variation

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DEER FARMING IN KOREA : ON-FARM SURVEY IN KYUNG-KEE AND CHUNG-BUK PROVINCES

  • Kwak, W.S.;Kim, K.H.;Kim, C.W.;Jeon, B.T.;Lee, S.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.7 no.3
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    • pp.347-355
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    • 1994
  • Thirty farmers, representing three major deer counties in Kyung-Kee province and 50 farmers scattered in Chung-Buk province were interviewed to determine the current status of the Korean deer industry. Items surveyed were general information, farmed deer breeds. farm facilities, feeding and nutrition, hygiene and disorder incidence, velvetting, income sources, products and their sale, management problems and herd size control. The 888 deer farmed in Kyung-Kee province included spotted deer (Cervus nippon. 69.4%), red deer (Cervus elaphus, 6.1%), wapiti (Cervus elaphus canadensis, 12.2%), spotted $\times$ red deer hybrids (6.2%), red deer $\times$ wapiti hybrids (4.6%). and fallow deer (Dama dama, 1.5%). Poor information on feeding was evidenced by wide variation among farms of daily feed supply and ratios of forage to concentrate, and poor nutritional considerations according to physiological status of deer. Hygiene needed more attention. The incidence of diseases and disorders was high: enteritis (73.3% in Kyung-Kee province), fractures (60.0%), and dystocia (56.7%). The major source of farm income was velvet antler and its blood. To improve productive efficiency, attention should be given to improving farm facilities, simplified product marketing, developing standard feeding system, and economic grazing system.

A Study on Development Potential of Shallow Geothermal Energy as Space Heating and Cooling Sources in Mongolia (몽골의 천부 지열에너지(냉난방 에너지)개발 가능성에 관한 연구)

  • Hahn, Jeong-Sang;Yoon, Yun-Sang;Yoon, Kern-Sin;Lee, Tae-Yul;Kim, Hyong-Soo
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
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    • v.8 no.2
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    • pp.36-47
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    • 2012
  • Time-series variation of groundwater temperature in Mongolia shows that maximum temperature is occured from end of October to the first of February(winter time) and minimum temperature is observed from end of April to the first of May(summer time). Therefore ground temperature is s a good source for space heating in winter and cooling in summer. Groundwater temperatures monitored from 3 alluvial wells in Ulaabaatar at depth between 20 and 24 m are $(4.43{\pm}0.8)^{\circ}C$ with average of $4.21^{\circ}C$ but mean annual ground temperature(MAGT) at the depth of 100 m in Ulaanbaatar was about $3.5{\sim}6.0^{\circ}C$. Bore hole length required to extract 1 RT's heat energy from ground in heating time and to reject 1 RT's heat energy to ground in summer time are estimated about 130 m and 98 m respectively. But in case that thermally enhanced backfill and U tube pipe placement along the wall are used, the length can be reduced about 25%. Due to low MAGT of Ulaabaatar such as $6^{\circ}C$, the required length of GHX in summer cooling time is less than the one of winter heating time. Mongolia has enough available property, therefore the most cost effective option for supplying a heating energy in winter will be horizontal GHX which absorbs solar energy during summer time. It can supply 1 RT's ground heat energy by 570 m long horizontally installed GHX.

Evaluation of Mass Variation of Aspheric Glass tens Using Resonant Ultrasound Spectroscopy (비구면 렌즈의 질량변화 평가를 위한 RUS의 적용)

  • Heo, Uk;Im, Kwang-Hee;Yang, In-Young;Kim, Ji-Hoon
    • Journal of the Korean Society for Nondestructive Testing
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    • v.27 no.2
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    • pp.183-189
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    • 2007
  • Ultra precise processed parts are required together with the development of optoelectronics industry. As important parts of optoelectronics industry, there are ferrule of optical connector and lens for optical devices. In particular, the lens requires high reliability with high precision without including flaws. These optical modules need ultra precise processing in order to reduce the loss of light sources and various nondestructive inspections are carried out in the finishing stage to separate good and bad quality products. Therefore, it was analyzed through the characteristics of response of amplitude and resonant frequency according to the mass variations of aspheric lens that is used currently in laser printers.

An implementation of NDIR type $CO_2$ gas sample chamber and measuring hardware for capnograph system in consideration of the time response characteristics (시간응답특성을 고려한 2광원 1센서 방식의 capnograph 시스템용 NDIR식 $CO_2$ 가스 챔버 설계 및 측정 회로의 구현)

  • Park, I.Y.;Lee, I.K.;Lee, S.K.;Kang, K.M.;Kang, S.W.;Cho, J.H.
    • Journal of Sensor Science and Technology
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    • v.10 no.5
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    • pp.279-285
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    • 2001
  • The capnograph system for determining the partial pressure of carbon dioxide in the blood of a patient was developed based on the NDIR(non-dispersive infrared) absorption technology. NDIR gas analyzing method requires an optical absorption chamber and signal processing hardware. In this paper, we have designed and implemented NDIR type $CO_2$ gas chamber in consideration of the time response characteristics and lamp chopping frequency. And we have implemented signal processing hardware using two infrared sources to reduce the thermal background effect. The implemented gas chamber and signal processing hardware were tested in the temperature variation experiment and human expiratory experiment. The results showed that the system could produce a stable output signal and a good $CO_2$ gas concentration curve like a typical capnogram.

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Brightness and Fluctuation of Mid-Infrared Sky from AKARI Observations

  • Pyo, Jeong-Hyun;Matsumoto, Toshio;Jeong, Woong-Seob;Matsuura, Shuji
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.117.1-117.1
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    • 2011
  • We present the smoothness of mid-infrared sky brightness from the Japanese infrared astronomical satellite, AKARI observations. AKARI monitored the north ecliptic pole (NEP) during its cold phase with nine wavebands from 2.4 to 24 ${\mu}m$, out of which six mid-infrared bands are used in this study. Simple sinusoidal fit to the seasonal variation of the sky brightness shows that the mid-infrared brightness towards the NEP is not affected by small-scale features of the interplanetary dust cloud. We applied the power spectrum analysis to the images to search for the fluctuation of sky brightness. The fluctuation powers at 200 arcsecond are estimated to be at most $1.58{\pm}0.33\;nW\;m^{-2}sr^{-1}$ or 0.13% of the total brightness at $7{\mu}m$ and a tleast $0.64{\pm}0.11\;nW\;m^{-2}sr^{-1}$ or 0.02% at $18{\mu}m$. The residual fluctuations at a few arcminute scales at short mid-infrared wavelengths (7, 9, and 11 ${\mu}m$) are consistent with those expected from the diffuse galactic light. At long mid-infrared wavelengths (15, 18, and 24 ${\mu}m$) the measured fluctuations are comparable to or smaller than the one caused by photon noise and their sources are not identified. We conclude that the upper limit of the fluctuation in the zodiacal light is about 0.02% of the sky brightness.

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A Standard Guide to Physical Oceanographic Survey of the Effect of Thermal Discharge from a Nuclear Power Plant (원자력발전소 온배수 영향 해양물리분야 조사의 표준지침)

  • Lee, Jae-Hak;Ro, Young-Jae;Cho, Yang-Ki
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.12 no.1
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    • pp.43-49
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    • 2007
  • The methods of physical oceanographic surveys to examine the effect of thermal discharge from nuclear power plants in Korea have been reviewed and a standard guide to the survey is proposed. It is desirable that in situ observation and numerical thermal diffusion modeling are conducted simultaneously to describe the variation in temperature distribution affected by thermal discharge from a power plant because any observation or numerical modeling alone has limits to do so quantitatively. It is suggested that the field observation must be based on the concept of heat budget modeling considering all artificial and natural heat sources/sinks around the power plant. Any results from numerical modeling must reach to a certain statistical significance level to use for a standard temperature distribution. In addition, the development of standard numerical codes is proposed to improve the problems shown in the past numerical circulation and diffusion modelling.

Operating Characteristic Analysis of Optic Temperature Sensor for Overheat Detection in Panel Board (분전함에서 이상발열 감지를 위한 광온도센서의 동작특성 분석)

  • Moon, Hyun-Wook;Kim, Dong-Woo;Gil, Hyung-Jun;Kim, Dong-Ook;Lee, Ki-Yeon;Kim, Hyang-Kon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.23 no.10
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    • pp.100-106
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    • 2009
  • In this study, methods of overheat detection at the coupling or wire in electrical facility are investigated, operating characteristic about the optic temperature sensor for continuous on-line temperature monitoring in diagnostics system of electrical facility is analyzed. Heating sources in the experiment for operating characteristics of optic temperature sensor use black body and hot plate, output voltage of optic temperature sensor in accordance with temperature variation is analyzed. Overheat generation due to poor contact at the circuit breaker in panel board detects using a thermocouple, infrared thermal camera and optic temperature sensor, and experiment results are analyzed. The effect of optic temperature sensor is the same that of other methods. These results expect to use basic research material for adjusting field of electrical diagnostics system using RFID type optic temperature sensor in the near future.

Measurement of Grating Pitch Standards using Optical Diffractometry and Uncertainty Analysis (광 회절계를 이용한 격자 피치 표준 시편의 측정 및 불확도 해석)

  • Kim Jong-Ahn;Kim Jae-Wan;Park Byong-Chon;Kang Chu-Shik;Eom Tae-Bong
    • Journal of the Korean Society for Precision Engineering
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    • v.23 no.8 s.185
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    • pp.72-79
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    • 2006
  • We measured grating pitch standards using optical diffractometry and analyzed measurement uncertainty. Grating pitch standards have been used widely as a magnification standard for a scanning electron microscope (SEM) and a scanning probe microscope (SPM). Thus, to establish the meter-traceability in nano-metrology using SPM and SEM, it is important to certify grating pitch standards accurately. The optical diffractometer consists of two laser sources, argon ion laser (488 nm) and He-Cd laser (325 nm), optics to make an incident beam, a precision rotary table and a quadrant photo-diode to detect the position of diffraction beam. The precision rotary table incorporates a calibrated angle encoder, enabling the precise and accurate measurement of diffraction angle. Applying the measured diffraction angle to the grating equation, the mean pitch of grating specimen can be obtained very accurately. The pitch and orthogonality of two-dimensional grating pitch standards were measured, and the measurement uncertainty was analyzed according to the Guide to the Expression of Uncertainty in Measurement. The expanded uncertainties (k = 2) in pitch measurement were less than 0.015 nm and 0.03 nm for the specimen with the nominal pitch of 300 nm and 1000 nm. In the case of orthogonality measurement, the expanded uncertainties were less than $0.006^{\circ}$. In the pitch measurement, the main uncertainty source was the variation of measured pitch values according to the diffraction order. The measurement results show that the optical diffractometry can be used as an effective calibration tool for grating pitch standards.

Numerical Study on Hydraulic Fluid Flows Within Axial Piston Pumps (액셜 피스톤 펌프내 유압유 유동에 대한 수치해석적 연구)

  • Jeong, Jong-Hyun;Kim, Jong-Ki;Suh, Yong Kweon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.2
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    • pp.129-136
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    • 2010
  • Axial piston pumps have been widely used as power sources for hydraulic systems, but studies on the fluid flow within the pump have been usually performed using 1-D analysis because of the difficulties in considering the fluid compressibility, high-speed revolution, variation of the flow rate, and complicated geometry. The goal of this study was to understand the hydraulic fluid flow within axial piston pumps by using the 3-D numerical method and the process of generating discharge pressure ripples. To improve the convergence and robustness of the simulation model, a grid system was constructed with hexahedron-type grids around the valve plate. Furthermore, we employed an empirical formula to describe the relationship between the oil density and pressure. The CFD (computational fluid dynamics) results compared well with the experimental data.

Simultaneous 22GHz Water and 44GHz Methanol Maser Survey of Ultra-compact HII Regions

  • Kim, Won-Ju;Kim, Kee-Tae;Kim, Kwang-Tae
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.83.2-83.2
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    • 2012
  • We have carried out simultaneous 22GHz $H_2O$ and 44GHz Class I $CH_3OH$ maser survey of 112 ultra-compact HII regions (UCHIIs) twice in 2010 and 2011. We detected $H_2O$ maser and $CH_3OH$ maser emission from 76(68%) and 49(44%) UCHIIs, respectively. Among them 15 $H_2O$ masers and 32 $CH_3OH$ masers are new detections. These high detection rates suggest that the occurrence periods of both masers are significantly overlapped with the UCHII phase. $CH_3OH$ masers always have small (<10 km s-1) relative velocities with respect to the natal molecular cores, while $H_2O$ masers often show larger velocities. We find 20 UCHIIs with $H_2O$ maser lines at relative velocities >30 km s-1. The formation and disappearance of $H_2O$ masers is frequent over one-year time interval. In contrast, $CH_3OH$ masers usually do not show substantial variation in intensity, velocity, or shape. The isotropic luminosities of both masers well correlate with the bolometric luminosities of the central stars when data points of lowand intermediate-mass protostars are added: $L_{H_2O}=5.89{\times}10^{-9}{(L_{bol})^{0.69}}$ and $L_{CH_3OH}=4.27{\times}10^{-9}{(L_{bol})^{0.62}}$. They also tend to increase with the 2cm radio continuum luminosity of UCHIIs and the 850 um continuum luminosity of the associated molecular cores. We discuss some individual sources.

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