• Journal of Chest Surgery
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• 제15권4호
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• pp.451-455
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• 1982

For recently 2 years, 3 cases of esophageal achalasia were surgically treated by modified Heller operation with gastric fundoplication. Esophageal achalasia is functional disorder of lower esophagus of which symptoms are dysphasia, regurgitation, and weight loss. Preoperative diagnosis was made by clinical manifestations and radiologic examination, esophagoscopy and confirmed at operative table. Operative procedures are variable, but modified Heller operation is common method to handicap reflux esophagitis and postoperative esophageal stricture. Now, our patients who were surgically treated were well alive without complaining of specific symptoms for followed period.

• 약학회지
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• 제2권1_2호
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• pp.33-41
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• 1953

According to the results of the investigation of air condition on a movie hause in Seoul city, for the period August 1948 to August 1949, the results were considerable condition contrary to the expection due to lack of Ventilation. By the above equation, the total air ventilation volume, the avarage air volume of natural ventilation, and the air volume of artifical ventilation to be required of the seven movie hause in Seoul city are discussed (See table in page in this Journal)

• 약학회지
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• 제2권1_2호
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• pp.48-69
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• 1953

"Kimchi", which is a main side-dish on Korean table is the pickled vegitables with seasoning substances : such as onion red pepper, salt, water and etc. In this paper, the variation of pH, acidity (calculated as lactic acid) and sugar contents (calculated as dextrose) are investigated during the fermentation period of Kimchi and the effects of antiseptics (Brilliant green, malachite green, sodium benzate, salicylic acid, P-dichlor amino sulfonyl-benzoic acid) and hydrochlonic acid to prevent spoiling are studied on the Kimchi which is prepared by a simple method in this laboratory.

• 산업경영시스템학회지
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• 제19권39호
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• pp.229-234
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• 1996

When we analyze equipment replacement problem, we take the table of the duration period of tangible fixed asset on the corporation income tax law, and treat depreciation as simple allocation process for capital recovery. In this problem, there are some papers considering the concepts of economic depreciation. Those are not perfect model from a economical point of view. Therefore, we deal with equipment replacement problem considering the engineering valuation as well as the economic concept in the evaluation of asset.

• Structural Engineering and Mechanics
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• 제74권6호
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• pp.821-832
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• 2020

The fundamental period is an important parameter for seismic design and seismic risk assessment of building structures. In this paper, a simplified theoretical method to predict the fundamental period of masonry infilled reinforced concrete (RC) frame is developed based on the basic theory of engineering mechanics. The different configurations of the RC frame as well as masonry walls were taken into account in the developed method. The fundamental period of the infilled structure is calculated according to the integration of the lateral stiffness of the RC frame and masonry walls along the height. A correction coefficient is considered to control the error for the period estimation, and it is determined according to the multiple linear regression analysis. The corrected formula is verified by shaking table tests on two masonry infilled RC frame models, and the errors between the estimated and test period are 2.3% and 23.2%. Finally, a probability-based method is proposed for the corrected formula, and it allows the structural engineers to select an appropriate fundamental period with a certain safety redundancy. The proposed method can be quickly and flexibly used for prediction, and it can be hand-calculated and easily understood. Thus it would be a good choice in determining the fundamental period of RC frames infilled with masonry wall structures in engineering practice instead of the existing methods.

• 한국산학기술학회논문지
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• 제20권1호
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• pp.217-223
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• 2019

국내외에서 점토층이나 준설토 등이 있는 연약지반을 개량하고, 그 지반위에 구조물을 건설하는 수요는 점차적으로 늘어나고 있다. 그리고 이러한 개발과 더불어 태풍, 산사태, 지진 등과 같은 자연재해의 빈도와 규모도 증가하고 있다. 이러한 자연재해로 인한 피해를 예방하기 위한 방법 중 하나가 지반개량공법이다. 본 연구에서는 쇄석을 띠기초 형식으로 설치하였을 때의 주변지반의 가속도 변화를 1-G 진동대 실험을 이용하여 분석하였다. 점토를 이용하여 지반을 조성하고 기초는 쇄석을 띠형식으로 설치하였다. 주기가 다른 입력지진파에 대해 응답가속도와 응답스펙트럼을 분석하였다. 쇄석 띠기초와의 인접거리에 따른 가속도 변화를 분석하여 지진시 쇄석 띠기초가 주변지반의 가속도 변화에 미치는 영향을 평가하였다. Hachinohe 지진파 결과에서는 쇄석띠기초와의 거리에 비해 가속도가 큰 감소는 없지만, 두가지 지진파에 대한 최대응답가속도가 쇄석띠기초와의 거리에 반비례하였다. 응답스펙트럼 분석결과, 장주기와 단주기 입력파에서의 감쇠되는 주기가 달랐으며, 이와 같은 응답스펙트럼 변화가 가속도의 최대가속도값에 영향을 준 것으로 판단된다. Hachinohe 지진파에서는 쇄석띠기초와 멀어질수록 0.08~0.5초 사이의 주기에서 감쇠가 컸으며, Northridge 입력파에서는 쇄석띠기초와 멀어질수록 0.2초 이내의 주기에서 감쇠가 컸다.

• 수산해양교육연구
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• 제28권1호
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• pp.127-136
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• 2016

The purpose of this research is to conduct a comparative study on the characteristics of daily volatility spillovers across the stock markets of Korea, China, and Japan. We employ generalized spillover definition and measurement developed by Diebold & Yilmaz (2009, 2012). The sample period is January 5, 1993 to September 25, 2015. From a static full-sample analysis, we find that 8.60% of forecast error variance comes from volatility spillovers. From a 250-day rolling-sample analysis, we discover that there exist significant volatility fluctuations in the stock markets of Korea, China and Japan, expecially during the Asian Financial Crisis (1998-1999) and the US Credit Crisis (2008-2009) after the collapse of Lehman Brothers. From the net directional spillovers across three countries, we come upon that there is neither a definite leader nor a significant follower during the sample period.

• Earthquakes and Structures
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• 제5권1호
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• pp.1-22
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• 2013

Soft storey failure mechanism is a common collapse mode for masonry-infilled (MI) reinforced concrete (RC) buildings subjected to severe earthquakes. Simple analytical equations correlating global with local ductility demands are derived from pushover (PO) analyses for seismic assessments of regular MI RC frames, considering the critical interstorey drift ratio, number of storeys and lateral loading configurations. The reliability of the equations is investigated using incremental dynamic analyses for MI RC frames of up to 7 storeys. Using the analytical ductility relationship and a coefficient-based method (CBM), the response spectral accelerations and period shift factors of low-rise MI RC frames are computed. The results are verified through published shake table test results. In general applications, the analytical ductility relationships thus derived can be used to bypass the onerous PO analysis while accurately predicting the local ductility demands for seismic assessment of regular MI RC frames.

• 한국산업융합학회 논문집
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• 제21권6호
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• pp.409-418
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• 2018

In this study, experiments were carried out after fabricating and installing a physical model considering the size of the prototype. In the model test, the number of struts placed on the wall and the applied acceleration were selected as test variables. Two different types of waves, long-period and short-period, were applied with magnitudes of 0.05g, 0.1g, 0.2g, and 0.3g. Measured are displacements at specified points. As a result of the analysis, displacement exceeding the allowable displacement of the wall occurred at an acceleration greater than 0.05g to 0.1g depending on the seismic waves applied. Therefore guidelines have to be established through further studies for aseismic design of earth retaining walls.

• Journal of Nutrition and Health
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• 제9권4호
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• pp.11-18
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• 1976

In this third report influence of vibration on growth and on some metabolism of young growing rats fed on varying levels of protein was investigated. Forty eight (48) young growing male rats weighing about 60 grams were used, grouping to four (4) groups, twelve (12) rats each group. They were fed on 8%, 13%, 19%, and 26% casein diet respectively (See the table 1) for the period of 10 weeks experiment. During the experimental period the half number of the rats of each group were subjected to a given degree of vibration for two (2) hours daily. Observations for growth rate, food and protein efficiency ratios, organs development, cholesterol levels in aorta, total nitrogen, urea nitrogen and creatinine levels in urine may be summarized as follows 1. Growth was impaired by the vibration in all groups including 26% easein diet. 2. There is tendeney that in higher protein diets, the organs (See table 3) developed more well. And also the impairment of the organs development by the vibration revealed less in higher protein diets. 3. Food and protein efficiency ratios were generally decreased under vibration and the food efficiency was improved by increasing the protein level in diet. 4. Total and free cholesteral levels in aorta were increased by the vibration. Ester from/tatal ratio was 17.7% and 17.3% respectively at 8% and 13% protein diets and 54.8% and 54.2% at 19% and 26% protein diets. These show that, in higher protein diets, the vibration doesn't influence the cholesterol ratio. 5. Total nitrogen, urea nirogen and creatinine levels in urine were increased by increasing the protion level in diet and also increased by the vibration. 6. It seems that, according to the above observations, the vibration used in this experiment influenced, in certain extent, on physical development, physiological availability of nutrients, and on body metabolism. And it is also thought that higher protein diets act some good role in protecting body from suffering from vibration.