• 한국환경과학회지
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• 제4권2호
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• pp.121-139
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• 1995

Based on the Results of Marine Meteorological and Oceanographical Observations (1966 -1987), the phenomenon of chimney is found as a candidate for the formation of the Japan Sea Proper Water (JSPW). The chimney phenomenon occurs twelve times Inuring 1966∼ 1987. The water types in the chimney denoting the deep convection are similar to those of the JSPW 0∼ 1℃ in potential temperature, 34.0∼34.1 ‰ in salinity and 68∼80 cl/t in potential thermosteric anomaly from the sea surface to the deep layer. The static stabilities in the chimney stations are unstable or neutral. This indicates that the winter time convection occurs. The JSPW sunken from the surface layer of chimney in winter spreads out under the Tsushima Warm Current area, following the isosteric surface of about 76 cl/t in Potential thermosteric anomaly. The formation of the deep water of the JSPW is mainly affected by the cooling of the sea surface than the evaporation of winds because the temperature and the salinity on the isoteric surface of about 76 cl/t in potential thermosteric anomaly ate cold and low The phenomenon of chimney occurred in here and there of the area in the north of 40" 30'N, west of 138" E. This suggests that the deep water of the JSPW is formed not in a limited area but probably in the overall region of the northern open ocean.

• Journal of Information Processing Systems
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• 제14권2호
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• pp.322-345
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• 2018

Climate change has become a major challenge for sustainable development of human society. This study is an attempt to analyze existing literature to identify economic indicators that hamper the process of global warming. This paper includes case studies based on various countries to examine the nexus for environment and its relationship with Foreign Direct Investment, transportation, economic growth and energy consumption. Furthermore, the observations are analyzed from the perspective of China-Pakistan Economic Corridor (CPEC) and probable impact on carbon emission of Pakistan. A major portion of CPEC investment is allocated for transportation. However, it is evident that transportation sector is substantial emitter of carbon dioxide (CO2) gas. Unfortunately, there is no empirical work on the subject of CPEC and carbon emission for vehicular transportation. This paper infers that empirical results from various other countries are ambiguous and inconclusive. Moreover, the evidence for the pollution haven hypothesis and the halo effect hypothesis is limited in general and inapplicable for CPEC in particular. The major contribution of this study is the proposal of an energy efficient transportation model for reducing CO2 emission. In the end, the paper suggests strategies to climate researchers and policymakers for adaptation and mitigation of greenhouse gases (GHG).

• 동의생리병리학회지
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• 제27권4호
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• pp.453-459
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• 2013

The objective of this study was to evaluate the single oral dose toxicity of Polygalae Radix (PR) in male and female mice. PR extract (yield = 18.6%) was administered to ICR mice as an oral dose of 2,000, 1,000 and 500 mg/kg (body weight) according to the recommendation of Korea Food and Drug Administration (KFDA) Guidelines (2009-116, 2009). Animals were monitored for the mortality and the changes in body weight, clinical signs and gross observation during 14 days after dosing. Upon necropsy, organ weight and histopathology of 14 principal organs were examined. It was observed that there were no mortalities, clinical signs, changes on the body and organ weights, gross and histopathological observations against 14 principal organs related to PR extract up to 2,000 mg/kg. Therefore, 50% lethal dose ($LD_{50}$) and approximate LD of PR aqueous extracts after single oral treatment in female and male mice were considered over 2000 mg/kg the limited dosages recommended by KFDA Guidelines, respectively.

• 대한교통학회지
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• 제20권3호
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• pp.83-92
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• 2002

화물수단선택모형 구축은 화물 및 물류관련 연구에 있어서 중요한 역할을 차지한다. 그러나 이러한 화물수단 선택 모형을 구축하기 위해 실제 관측되는 자료(Revealed Preference:RP)를 이용하는 데는 한계가 존재하며 따라서 선호의식 기법을 활용한 Stated Preference(SP) 자료가 화물수단 선택 모형을 구축하는데 중요한 자료로 사용된다 SP 자료는 이처럼 화물교통 자료의 현실적인 한계를 극복할 수 있지만 SP자료를 이용하여 구축되어지는 화물수단모형인 경우 조사기법의 한계로 RP자료에는 존재하지 않는 편의가 발생한다. 본 논문은 SP 자료를 이용하여 수단선택모형 구축시 발생하는 편의 제거에 대한 연구이다. 특히 본 논문에서는 시뮬레이션 방법을 이용하여 개인의 다양한 선택행태 다양성(heterogeneity)과 이러한 다양성이 SP 다음 질문에 전이되는 문제점을 극복하는 새로운 개념의 화물수단 선택 로짓모형을 제시한다. 또한 단순 로짓모형이 갖고 있는 IIA 특성을 극복하는 화물수단 선택모형도 제시한다. 본 연구를 통해 화물교통에 존재하는 화주의 다양한 선택행태 분석뿐만 아니라 SP 수단선택 모형이 갖는 편의 극복에 본 연구가 일조하기를 기대한다.

• 기술혁신연구
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• 제23권3호
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• pp.115-135
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• 2015

사실상의 표준 등장은 산업의 경쟁적 상황의 변화를 가져오는 주요한 사건이며, 등장 이전의 디자인 경쟁에서 등장 이후 제품 경쟁으로 경쟁상황을 변화시킨다. 이는 사실상의 표준 등장이 산업의 발전과 기업의 전략수립에 주요한 변환점이 된다는 의미이다. 하지만, 현재까지 이러한 사실상의 표준과 기업 퇴출에 대한 연구는 미미한 실정이다. 본 연구에서는 1983년부터 2002년까지 미국의 레이저 프린터 산업을 대상으로 사실상의 표준 등장 이후, 기업퇴출에 대한 연구를 수행하고자 한다. 이를 위해 Cox의 비례위험모형을 사용하였으며, 제품수준 6650개의 표본을 바탕으로, 총 119개 회사를 대상으로 분석하였다. 이 연구의 결과는 다음과 같다. 사실상의 표준 등장 이전에 진입한 기업일수록 퇴출될 확률이 증가하였다. 사실상의 표준 등장 이후, 시장에서 경쟁기업 수가 많은 경우에는 기업의 퇴출 확률이 줄어들었으며, 제품 경쟁이 심해질수록 퇴출 확률이 증가하는 것으로 나타났다. 본 연구의 결과는 사실상의 표준 등장 이후 산업의 독특한 경쟁상황을 나타내고 있다. 이를 바탕으로, 사실상의 표준 등장에 따른 산업의 경쟁적 환경에 대한 전략적 그리고 정책적 함의를 도출하였다.

• Journal of Nutrition and Health
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• 제14권4호
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• pp.209-219
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• 1981

To evaluate long-term metabolic response of free-living Korean subjects consuming local sources adequately or slightly below habitual intake. Subjects, six male medical students aged 23-25 years were free-living, but consumed diets in the metabolic unit. They were healthy as determined from medical laborarory tests. They belong to the Korean middle-class. Temperature of outdoor during study were ranged between -2 to $26^{\circ}C$, whereas the indoor were $18-22^{\circ}C$. Animal protein ranged between 25-30% of total calorie. The three meals and a vitamin supplement to meet recommendation were given daily. Three 50day periods following the design were used to test the protein-energy adequacy of the diet. Urinary nitrogen excretion was measured daily. Fecal samples were pooled for the last 5 days of each week. Nitrogen balance was computed using 5mg N/Kg skin and miscellaneous losses. Body weight was measured daily. The study was covered on 126 metabolic observations weekly. Body weight changes were relatively stable with the energy intake of 37-44Kca1/kg, and N-balances were also relatively stable, but it was influenced by physical and or mental stress somehow. It could be assumed that the mean protein and energy requirement were $190{\pm}10mg$ N/Kg with $41{\pm}2$ Kcal/kg, and the mean digestibility of protein was 81% on these subjects with the experimental conditions. The protein requirement, however, could be cut down somewhat with some limited increaing of energy intake under parameters of N-balance and maintaining body weight. It was also observed a tendency of the requirement were getting smaller with the increase of body size.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.165-170
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• 1999

We have investigated the mixed-state Hall effect in HgBa$_2CaCu_2O_6$, HgBa$_2Ca_2Cu_3O_8$, and Tl$_2Ba_2Cau_2O_8$ thin films as functions of the magnetic field up to 18 T. At high fields and low temperatures, the scaling exponent in ${\rho}_{xy}$ = A${\rho}_{xx}\;^{\beta}$ shows a universal behavior, ${\beta}$ = 1 ${\pm}$ 0.1, regardless of the field, the number of CuO$_2$ layers, the types of defects, and even the types of compounds. At low fields and high temperatures, p = 1 ${\pm}$ 0.1 also appears as a universal number although the observed field range is rather limited. These observations show the universal scaling of Hall resistivity in the regions of the clean and the moderately clean limit, consistent with a theory based on the midgap states in the vortex core.

• 응용통계연구
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• 제23권3호
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• pp.521-531
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• 2010

구간중도절단은 중도절단의 가장 일반적인 개념으로 구간중도절단자료는 의학 및 역학분야의 연구에서 흔히 관찰된다. 본 연구에서는 구간중도절단의 상황에서 생존함수와 중간생존시간을 추정하는 방법으로 평균대치법과 자기일치법을 비교 연구하고, 실제 자료로 혈우병환자에서 선천성면역결핍바이러스 감염시점을 추정하였다. 또한 구간중도절단자료를 생성하는 새로운 방법을 제시하였으며, 생성된 구간중도절단자료를 이용한 모의실험을 통하여 두 추정치에 대한 다양한 비교연구를 시행하였다. 구간중도절단자료에서 생존함수와 중간생존시간을 추정할 경우 중도절단율이 크지 않다면 평균대치법이 자기일치법보다 더 우수한 추정치로 판명되었다.

• 경영과정보연구
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• 제28권2호
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• pp.113-134
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• 2009

본 연구는 외환위기 이후에 외국인 투자비중이 기업가치에 미치는 영향을 실증분석하였다. 2000년부터 2007년까지 8년 동안 외국인지분율이 영(0)보다 큰 기업을 대상으로 분석한 결과 외국인 투자비중이 증가할수록 기업가치는 상승하는 것으로 나타났다. 이러한 관계는 동시성을 고려해 외국인지분율과 기업가치를 내생변수로 보고 분석을 해도 동일하게 성립하였다. 한편 역으로 외국인이 기업가치가 높을 것으로 전망되는 기업에 선별적으로 투자한다는 증거는 발견할 수 없었다. 외국인 투자비중 확대에 따른 기업가치의 상승은 외국인투자자가 투자기업에 대한 감시 및 견제 역할을 충실히 수행하기 때문인 것으로 해석된다. 이는 전통적으로 소유경영자에 의한 기업지배가 강한 우리나라 기업들이 소유분산이 심화되는 과정에서 외국인투자자를 비롯한 기관투자자가 투명성 제고 및 지배구조 개선에 있어 중요한 역할을 하고 있음을 의미한다고 하겠다.

• 한국환경과학회지
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• 제21권6호
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• pp.739-747
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• 2012

Due to the difficulties for measuring flood discharge in the dangerous field conditions, conventional instruments with relatively low accuracy such as float still have been widely utilized for the field survey. It is also limited to use simple stage-discharge relationship for assessment of the flood discharge, since the stage-discharge relationship during the flood becomes complicated loop shape. In recent years, various non-intrusive velocity measurement techniques such as electromagnetic wave or surface images have been developed, which is quite adequate for the flood discharge measurements. However, these new non-intrusive techniques have little tested in the flood condition, though they promised efficiency and accuracy. Throughout the field observations, we evaluated the validity of these techniques by comparing discharge and velocity measurements acquired concurrently during the flood in a mountain stream. As a result, the flood discharge measurements between electromagnetic wave and surface image processing techniques showed high positive relationship, but velocities did not matched very well particularly for the high current speed more 3 m/s. Therefore, it should be noted here that special cares are required when the velocity measurements by those two different techniques are used, for instance, for the validation of the numerical models. In addition, authors assured that, for the more accurate flood discharge measurements, velocity observation as well as stage height is strongly necessary owing that the unsteady flow occurs during the flood.