• Journal of Advanced Marine Engineering and Technology
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• 제24권2호
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• pp.57-62
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• 2000

The effect of exhaust gas recirculation(EGR) on the characteristics of exhaust gas emissions, and SFC are experimentally investigated by four-cylinder, four-cycle and direct injection marine diesel engine. In order to reduce the soot contents in the recirculated exhaust gas to intake system of the engines, a soot removal system of a cylinderical-type scrubber is specially designed and manufactured for the experimental system. (1) SFC is increased in downward convex curve style with increasing excess air ratio, it is increased with increasing EGR rate at the same excess air ratio. (2) NOx emission is reduced in downward convex curve style with increasing excess air ratio, it is reduced with increasing EGR rate at the same excess air ratio. (3) Soot emission is decreased in downward convex curve style with increasing excess air ratio, it is reduced with increasing EGR rate at the same excess air ratio. (4) CO emission is increased in nearly straight line style with increasing excess air ratio, it is increased with increasing EGR rate at the same excess air ratio. (5) HC emission is not constant tendency with increasing excess air ratio, it is increased with increasing EGR rate at the same excess air ratio.

• 환경위생공학
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• 제11권3호
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• pp.53-61
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• 1996

The subject of this study was to analyse overviews of companies which exceed TLV by industry, hazardous factors, and to estimate the numbers of companies measured in 1993 and the implementation rate of working environment measurement by the act of industrial safety and health The result of this study was as follow. 1. The number of cases which exceed TLV was 5,937 companies. In distribution of excess companies by the scale of workers, small scale cases under the 49 workers were 3,150 companies(53.0%) of total cases, medium scale cases between 50 - 299 workers were 2,248 companies(37.9%), and large scale cases over 300 workers were 539 companies(9.1%). By the industry of excess companies, it was marked high rate in manufacture of fabricared metal products(except machinary and equipment), manufacture of textiles of each 1,048 companies(17.7%), and 1,018 companies(17.1%). By the area of excess companies, it was shown high rate in Kyeongki area marked 1,679 companies(28.3%) and Daegu-Kyeongbuk area were marked 1,417 companies (23.9%). By the hazardous factors of excess companies, noise was recorded high rate in 5,160 companies (86.9%), dust was shown in 1,245 companies(21.0%), organic solvent was marked 130 companies(7.9%). The number of excess factors by the company was 1.2. In this result, the more it was bigger scale companies, the more excess factors were much more and the more it was recorded higher rate in noise organic solvent heavy metals, etc. 2. The measured cases in institutes during 1994 were 1,596 companies, and excess cases were 157 companies(9.8%) among them. By the scale of workers, small scale cases under the 49 workers were 190 companies (17.9%) among 1,064 companies, cases of medium scale cases between 50-299 workers were 127 companies (27.9%) among 463 companies, and large scale cases over 300 workers were 31 companies(44.9%) among 69 companies. In this result industry of the highest rate shown was manufacture of basic metals in 20 companies exceeded among 53 companies (37.7%), and was manufacture of pulp, paper production in 14 companies exceeded among 40 companies(35.0%), and the excess rate were high in bigger scale. 3. Companies estimated by the data of excess cases and excess rate in 1993 were 30,474 implementation rate estimated for measurement of working environment was 34.3% of companies in korean industry. In this result, it was comparatively shown of measurement rate for the working environment in manufacture of pulp, paper product, manufacture of machinary and equipment n.e.c., and of high measurement rate and excess rate in manufacture of electrial machinary and apparatus, and manufacture of basic metals.

• 한국산업보건학회지
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• 제29권1호
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• pp.21-26
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• 2019

Objective: The aim of this study is to analyze an excess trend for domestic permissible exposure limit of trichloroethylene based on previous literature review. Materials and Methods: The research object is a trichloroethylene among 13 chemical substances regulated with PEL(Permissible Exposure Limit) in Occupational Safety and Health Act. The information utilized from this study is the work environment measurement data from 2004 to 2013. The highest level among concentration data measured at various workplaces was selected as a representative value through data process. N.D. (Not Detected) data was considered as 1/2 of LOD(Limit Of Detection). Results: Among work environment measurement data between 2004 and 2013, the highest number of excess workplace and excess rate(24 sites & 1.15%) was observed in 2008's data when applying the PEL(50 ppm) of trichloroethylene. When they are compared with the ACGIH's TLV-TWA(10 ppm), 2008's data showed the highest number of excess workplace and excess rate(175 sites & 8.37%). The number of excess workplace and excess rate related to PEL of trichloroethylene showed increase trend in 2005 but tended to decrease after 2008. Conclusions: Based on the results obtained from this study, the exposure level of trichloroethylene in case of domestic workers is not considered as a safe phase regardless of the year of work environment measurement year. Thus, a strictly preventive management in workplace should be provided for reducing exposure level of trichloroethylene.

• 대한기계학회논문집B
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• 제31권6호
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• pp.539-546
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• 2007

An experimental study was performed to investigate the characteristics of chemiluminescence in a radiant burner, varying the excess air ratio from 0.91 to 1.67 at firing rate 80.5 to 134.2 kW/m2 on $OH^*,\;CH^*,\;{C_2}^*$ in LNG-Air premixed flames. The signals from electronically excited states of $OH^*,\;CH^*,\;{C_2}^*$ were detected using a Intensified Couple Charged Detector (ICCD) camera. The measurements of exhausted emission were made to investigate the correlation between chemiluminescence and emissions. The chemiluminescence intensity was increased with increase of firing rate like characteristics of $NO_x$ emission. $NO_x$ also increased with increase of firing rate and excess air ratio. It is found that offset of firing rate is more dominant excess air ratio $NO_x$ emission. The maximum chemiluminescence intensity occurs near the stoichiometric excess air ratio or lean conditions in case of high firing rate and the maximum intensity occurs rather than rich conditions in case of relatively low firing rate. Amount of $NO_x$ emission is maximum at near stoichiometric excess air ratio, which is chemiluminescence intensity is maximum.

• Journal of Nutrition and Health
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• 제25권6호
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• pp.492-500
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• 1992

본 연구에서는 비타민 A 과량 섭취가 비타민 K 기능에 미치는 영향을 알아보기 위하여 carboxylase의 기질인 쥐의 간내 microsome 단백질과 첨가된 펩티드의 vitamin K-dependent carboxylation rate를 측정하였다. In vitro 실험에서는 정상 vit.A 섭취군의 간 microsome을 vit.A 로 incubation했을때 간 내 prothrombin 선구 물질이나 첨가된 peptide기질의 carboxylation rate는 영향을 받지 않았다. 이와 비슷한 양상으로서 무비타민 K 식이와 함께 비타민 A를 정상수준 혹은 과잉 수준으로 섭취한 쥐를 비교한 경우에는 동일군 간에는 carboxylation rate에 유의한 차이를 나타내지 않았다. 그러나 비타민 A 과잉군의 간내 단백질의 carboxylation rate는 대조군에 비하여 증가하는 경향이었다, 비타민 A 과잉군은 비타민 A로 incubate한 경우나 하지 않은 경우 모두 대조군에 비하여 약 2~3 배 의 carboxylase 활성을 보였다. In vivo study 에서는 첨가된 peptide에 대한 carboxylase활성은 비타민 A 광일 섭취에 의하여 영향을 받지 않았다. 그러나 간 내 단백질의 carboxylation rate는 비타민 A과잉군이 대조군에 비하여 2~3 배나 더 높았다. Carboxylase 활성은 대조군이나 비타민 A과잉군 모두 연구기간이 진행될수록 더 증가하였다. 그리고 간 내 단백질의 carboxylation에 대한 비타민 A 과잉 효과는 실험 식이를 시작한 후 일주일 정도에서 나타나기 시작하였다. 그러므로 이 연구 결과는 비타민 A 과잉 시에는 과잉증이 빠른 시일내에 일어나며, 비타민 A 과잉은 비타민 K 결핍의 지표인 prothrombin 의 선구물질을 증가시킨다는 것을 시사한다.

• 재무관리연구
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• 제12권2호
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• pp.207-219
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• 1995

This paper develops an equilibrium asset pricing model with taxation in the economy. The expected excess rate of return on a risky asset is shown to be an increasing function of the covariance of asset return with aggregate consumption rate changes and the covariance of asset return with the tax rates as well. Thus, the expected execss rate of return can be decomposed as the consumption risk premium and the tax premium. The capital asset pricing model derived in the absence of taxes is shown to understate the expected excess rate of return and to have a misspecification error in the economy with taxation.

• Korean Journal of Acupuncture
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• 제33권4호
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• pp.176-182
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• 2016

Objectives : This study was designed to analyze the characteristic of heart rate variability(HRV) changes between Deficiency Pattern and Excess Pattern in Stroke Patients admitted to the hospital. Methods : We measured heart rate variability of stroke patients who were admitted to the Department of Korean Internal medicine, Stroke and Neurological Disorders Center from February 1, 2015 to May 30, 2016. We recruited a total of 28 stroke patients and heart rate variability tests were performed on the first day of admission, 2weeks after admission, and 4 weeks after admission. Results : VLF and LF/HF ratio significantly increased over time in Deficiency Pattern group compared with those in the Excess Pattern group. Conclusions : This results suggest that the parasympathetic function of Deficiency Pattern group is lower than that of the Excess Pattern group, resulting in imbalance of the autonomic nervous system.

• 한국농공학회논문집
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• 제62권6호
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• pp.97-109
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• 2020

The objective of this study was to assess spatial variation of the target water quality criteria and excess rate in Nakdong river basin after the Total Maximum Daily Loads (TMDLs). For this, 41 total water quality monitoring stations were selected BOD and T-P data were collected from 2003 to 2019. The annual average water quality of BOD and T-P were calculated and compared with the target water quality for each stations by peroid. As a result of analyzing the BOD, Kumho A, Nakbon F, Namgang D, Miryang B, Wicheon B and Hoecheon A exceeded the target water quality criteria for two consecutive times. For T-P, Nakbon N, Naeseung B, Miryang A, Hwanggang A and Hoecheon A exceeded the target water quality criteria twice in a row. In the case of T-P, the target water quality excess rate was relatively low after the TMDLs implementation compared to before the TMDLs implementation. However, in the case of BOD, there was no difference in the target water quality excess rate before and after TMDLs. As a result, the overall annual average water quality shows a decreasing trend, but it is necessary to manage the water quality for the Nakdong river basin that exceed the target water quality.

• 한국세라믹학회지
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• 제31권11호
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• pp.1299-1306
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• 1994

Effect of MgO content on microstructural evolution and microwave dielectric properties of Ba(Mg1/3Ta2/3)O3 system was investigated. MgO content was varied from 10 mol% deficiency to 10 mol% excess of stoichiometric composition, respectively. It was found that MgO-deficient specimen showed faster grain growth rate than stoichometric and MgO excess BMT system. Besides, sandwich type precipitates of Ba5Ta4O15 which was formed within the BMT grain, might lead to the anisotropic grain growth of BMT grain. On the contrary, in MgO excess specimen, BMT grain growth rate was retarded by precipitations of MgO phase in grain boundary. Besides, the Q values of MgO-deficient showed lower than MgO-excess due to precipitations of Ba5Ta4O15 within BMT grain.

• East Asian Economic Review
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• 제18권2호
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• pp.111-142
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• 2014

We examine whether country fundamentals help explain the cross-section of currency excess returns. For this purpose, we consider fundamental variables such as default risk, foreign exchange rate regime, capital control as well as interest rate in the multi-factor model framework. Our empirical results show that fundamental factors explain a large part of the cross-section of currency excess returns. The zero-intercept restriction of the factor model is not rejected for most currencies. They also reveal that our factor model with country fundamentals performs better than a factor model with usual investment-style factors. Our main empirical results are based on 2001-2010 balanced panel data of 19 major currencies. This paper may fill the gap between country fundamentals and practitioners' strategies on currency investment.