• 한국기계가공학회지
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• 제17권1호
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• pp.130-137
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• 2018

In long freight trains, there is a brake time delay in the neighboring freight cars that causes damage and fractures of couplers, especially the knuckle of them. If there is a problem for couplers in the cars, this could cause a derailment and lead to damage of human life and property damage. In this study, maximum forces on the couplers are studied when a long freight car brakes, with brake delay time and coupler gap. We have made a dynamic model of 50 freight cars and couplers, applying contact between couplers and a characteristic curve for expressing force and displacement of buffers with SIMPACK, a multi-body dynamics program. We use EN 14531-2 from the British Standards Institution, a standard of freight car brakes for the verification of the dynamic model. We also use a simplified method to analyze the dynamic model of 50 freight cars. With changing coupler gap and brake delay time, we do comparative analysis with AAR M-201 from the Association of American Railroads, a standard of AAR couplers. From this result, we find that the standard on fatigue limit is satisfied, such that the brake delay time is within 0.06 second if the coupler gap of the AAR coupler is within 20 millimeters.

• 대한정형도수물리치료학회지
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• 제10권2호
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• pp.57-72
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• 2004

Background : The part to be very important that we make the physical development rightly at elementary school student days. Objective : This study investigated the relation of a physical health status which itself recognizes and an exercise performance situation out for an elementary school students. Methods : This cross-sectional study examined health and exercise performance status of 1,032 elementary school children. To examine children's a physical injury experience and injury occurrence characteristic and a personal computer utility condition, a body alignment status of the student which parents recognize and the relation of a fatigue and concentration level was an investigation with other factors. Results: An average age of the children was the 10.95 yr and an average weight was the 39.02 kg and an average height was the 145.17cm. The student to be experiencing currently an pain occurrence was 192(19.07%). It was most high to the grade 6(23.33%) compared with different grade(p<.01). Physical pain occurrence rate did not exist by gender(p>.05). There is most an pain occurrence region the ankle(38.0%). They had a 27.19% an physical injury experience of the students. A injury rate was revealed that were high as were the high grade(grade 6, 36.72%)(p<.01). A reason of the injury rate was high in a collision at the body(19.84%), falling down(18.68%) sequence at a traffic accident(22.96%)(p<.05). There were the significant relation to the school year the reason of the injury (p<.05). Currently there was the student to be taking special exercises a 57.97%. This that they have the relation with exercise with physical pain students to recognize 23.8%. The significant relation did not exist in the physical exercise execution and pain occurrence on the body(p>.05).

• Structural Engineering and Mechanics
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• 제42권4호
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• pp.507-530
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• 2012

Age-related problems especially corrosion and fatigue are normally suffered by weatherworn ships and aging offshore structures. The effect of corrosion is one of the important factors in the Common Structural Rule (CSR) guideline of the ship design based on a 20 or 25 years design life. The aim of this research is the clarification of the corrosion effect on ultimate strength of stiffened panels on various types of double hull oil tankers. In the case of ships, corrosion is a phenomenon caused by the ambient environment and it has different characteristics depending on the parts involved. Extensive research considering these characteristic have already done by previous researchers. Based on this data, the ultimate strength behavior of stiffened panels for four double hull oil tankers such as VLCC, Suezmax, Aframax, and Panamax classes are compared and analyzed. By considering hogging and sagging bending moments, the stiffened panels of the deck, inner bottom and outer bottom located far away from neutral axis of ship are assessed. The results of this paper will be useful in evaluating the ultimate strength of an oil tanker subjected to corrosion. These results will be an informative example to check the effect of ultimate strength of a stiffened panel according to corrosion addition from CSR for a given type of ship.

• 사상체질의학회지
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• 제13권1호
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• pp.109-118
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• 2001

1. The purpose of this study This study was performed on the basis of clinical consideration about rhinitis patients who suffered from sneeze, rhinorrhea, rhinocleisis and etc. And we checked the clinical inclination of this disease and the characteristic treatments of Sasang Constitutional Medicine. 2. The method of this study For 17 months from October in 1999 to April in 2001 we selected outpatients who had consulted for rhinitis more than twice in the department of the Sasang Constitution of the Bundang Oriental medical hospital, Dongguk University, and 31 of those were confirmed of their course of treatment. From their medical records and history, we learned the general characterisics and patterns of rhinitis, and the qualities and effects of its various treatment. 3. The result of this study The result were as follows ; 1) The rate of patients who have had the symptoms over the two years was 74.2%. 2) In the distribution of chief symptoms, sneeze occupied 80.6% of all appealed symptoms, rhinocleisis 77.4%, rhinorrhea 71.0%, intranasal pruritus 54.8%, postnasal drip 16.1%, orderly. 3) The treatment period was about 30days. The method of treatment was the Herb-med Tx, acupuncture Tx and etc. The herb-med ingestion was about two times in that period. 4) On the effect of treatment, Sneeze and rhinocleisis were improved. 5) The symptoms of rhinitis was more depravated by fatigue and stressful condition than weather condition. This result shows that the improvement of general condition has an effect on the rhinitis treatment.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.41-43
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• 1999

Among the feffoelectric thin films that have been widely investigated for ferroelectric random access memory (FRAM) applications, SrBi$_2$Ta$_2$$O_{9}$ thin film is appropriate to memory capacitor materials for its excellent fatigue endurance. However, very few studies on etch properties of SBT thin film have been reported although dry etching is an area that demands a great deal of attention in the very large scale integrations. In this study, the a SrBi$_2$Ta$_2$$O_{9}$ thin films were etched by using magnetically enhanced inductively coupled Ar/CHF$_3$ plasma. Etch properties, such as etch rate, selectivity, and etched profile, were measured according to gas mixing ratio of CHF$_3$(Ar$_{7}$+CHF$_3$) and the other process conditions were fixed at RF power of 600 W, dc bias voltage of 150 V, chamber pressure of 10 mTorr. Maximum etch rate of SBT thin films was 1750 A77in, under CHF$_3$(Ar+CHF$_3$) of 0.1. The selectivities of SBT to Pt and PR were 1.35 and 0.94 respectively. The chemical reaction of etched surface were investigated by X-ray photoelectron spectroscopy (XPS) analysis. The Sr and Ta atoms of SBT film react with fluorine and then Sr-F and Ta-F were removed by the physical sputtering of Ar ion. The surface of etched SBT film with CHF$_3$(Ar+CHF$_3$) of 0.1 was analyzed by secondary ion mass spectrometer (SIMS). Scanning electron microscopy (SEM) was used for examination of etched profile of SBT film under CHF$_3$(Ar+CHF$_3$) of 0.1 was about 85˚.85˚.˚.

• 대한안전경영과학회지
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• 제17권3호
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• pp.115-123
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• 2015

The study conducted statistical analysis of survey on the 239 workers participating in national Tower Crane installation/dismantlement in order to identify work environment and health hazard exposure of Tower Crane workers. Consequently for work related safety status of Tower Crane workers, the number of installation/dismantlement work was the highest at 15-20 times per month, and safety equipments were not arranged at work and they felt highly anxious when boarding on the Tower Crane. Furthermore, it is found that they feel anxious working in the influence of the weather, noise, vibration, wind, the sun ray, and structure characteristic. They have very low satisfaction in the insecureness of workplace and the work environment, and recognizes that their work affect highly on the health. 81.6% of workers have experienced accident at work, the cause of accidents were mainly due to poor work environment, and the health abnormality they have experienced were mostly fatigue and concentration reduction. For job stress, job demand and conflict in relationship were the highest sections. Total 66.5% of workers complained of musculoskeletal disorder related subjective symptom, and back pain patients were the highest of all groups.

• International Journal of Advanced Culture Technology
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• 제9권3호
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• pp.131-141
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• 2021

The present study is following a series of research investigations on design resources coming from collected data referring to users' awareness and preferences. The aim of this research is to test the Healthcare Environmental Color Index as a basis for practitioners in the field of healthcare design. An array of color samples selected from previous research, have been presented to the respondents via an online survey, in order to identify the preferences of the two groups on the relation between environmental color and health. As a result of the first experiment and through the comparison of processed data, the maximum percentage of respondents from each group is validating the relation between environmental color and health. For the second experiment we intend to highlight the patterns of color preferences for each group, and thus to test the color samples healing function. The compared data also showed a higher awareness of Koreans than Romanians on the potential of color applied to healing environment. Last but not least in the third experiment we show the top five color samples preferred by each group. It is significant that the comparison of the results validated once more some of our previous findings related to the healthcare environment, such as: the general preference for the green hue (associated to fatigue relax according to color psychology) and the blue hue (sedation release effect) but also the yellow hue - associated to bright energy. Three out of the top five preferred color samples have been identical to both groups while the other two samples have shown characteristic variations. These results show that similarities are strong and can be used in a glocal design strategy as an accessible tool for any practitioner. Based on the Healthcare Environmental Color Index and users' preferences analysis, a new design culture for healthcare can be established and developed.

• 경영과정보연구
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• 제34권5호
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• pp.191-212
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• 2015

본 연구는 판매원의 행동에 영향을 미치는 요소로서 판매원의 관계신념 및 감정조절전략을 제시하고자 한다. 판매원의 경우 고객과의 상호작용은 그들의 직무이며 원만한 고객관계는 그들의 목표달성과 기업의 성과달성에 매우 중요하다. 따라서 이러한 원만한 관계를 형성할 수 있는 요소로서 본 연구는 관계신념을 제시하고자 한다. 대인과의 관계에서 어떠한 관계신념을 가지고 있는가하는 것은 개인의 인지적, 정서적, 동기적 측면에 영향을 미치기 때문에 판매원이 가진 관계신념에 따라 고객관계의 질, 경험이 달라질 수 있다. 또한 이러한 관계신념은 판매원이 고객과의 관계에서 경험하는 부정적 감정 조절전략에도 영향을 미치게 되는데 판매원이 어떠한 조절전략을 더 많이 사용하는가에 따라 판매원의 행동이 달라질 수 있다. 본 연구는 판매원의 관계신념, 감정조절전략, 그리고 친소비자행동의 관계를 통해 고객과 판매원의 관계의 질을 증대시키고 이 과정에서 판매원의 성과극대화 및 상황적응력을 높일 수 있는 전략적 방안에 대해 논의하고자 한다. 연구결과 판매원의 관계신념이 부정적 감정 조절전략과 친소비자행동에 영향을 미치는 것으로 나타났으며 부정적 감정 조절전략은 친소비자행동에 영향을 미치는 것으로 나타났다. 친밀관계신념이 높을수록 능동적 조절전략, 지지추구조절전략을 이용하여 부정적 감정을 조절할 가능성이 높고, 통제관계신념이 높을수록 회피/분산 조절전략을 이용하여 부정적 감정을 조절할 가능성이 높은 것으로 나타났다. 또한 친밀관계신념은 친소비자행동을 증가시키지만 통제관계신념은 친소비자행동을 감소시키는 것으로 나타났다. 부정적 감정 조절전략 중 능동적, 지지추구조절전략은 친소비자행동을 증가시키는 것으로 나타났고 회피/분산조절전략은 친소비자행동을 감소시키는 것으로 나타났다. 본 연구결과는 판매원의 관계신념과 부정적 감정 조절전략에 관심을 가질 수 있는 계기를 마련하고 있으며 판매원 선발 및 교육에 있어서의 중요한 지침을 제공하고 있다.

• 대한기계학회논문집A
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• 제37권8호
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• pp.1035-1041
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• 2013

본 논문은 KTX 안티롤바 너클부의 동특성 및 구조 안전성 평가를 위해 시험 및 수치적 방법을 사용하였다. 시험적 방법에서는 KTX와 KTX-산천 안티롤바 너클부의 동특성을 비교 평가하기 위해 호남선의 운행환경을 고려한 가속도 및 변형률 데이터를 각각 측정하였으며, 수치적 방법에서는 너클부에 대해 LS-DYNA 3D를 사용하여 구조 안전성 평가를 수행하였다. 이때 해석에 사용된 유한요소모델은 시험과 비교평가를 통해 신뢰성을 검증하였다. 수치해석 결과, 얇은 금속판 및 고무의 적층구조로 이루어진 너클부의 응력 및 속도장이 너클과 커넥팅로드 사이의 상대적 접촉 감소로 인해 두꺼운 강재로만 이루어진 너클부에 비해 좀 더 완화된 경향을 보였다. 그 결과 얇은 금속판과 고무로 구성된 너클 구조가 반복적인 외력 하중하에서 KTX 안티롤바의 탄성거동을 허용하여 동적 거동하의 구조적 안전성을 향상시키기 위한 최선의 방법임을 확인하였다.

• 콘크리트학회논문집
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• 제26권1호
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• pp.3-12
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• 2014

복합트러스교는 프리스트레스 박스거더교의 복부를 강재 트러스로 대체한 교량으로 자중이 경감되는 구조적 장점과 복부 개방구조로 인한 경관성이 매우 우수하여 최근 들어 많이 사용되고 있다. 이러한 복합트러스교의 핵심기술은 강재 트러스와 콘크리트 슬래브를 연결하는 격점구조이며 지금까지 여러가지 격점구조들이 개발되어 실험적 검증을 통해서 실교량에 적용해 오고 있다. 이러한 격점구조는 격점부 국부적인 거동뿐만 아니라 복합트러스 거더의 휨 및 피로 등 전체적인 거동을 좌우하기 때문에 이에 대한 연구가 계속 진행되고 있다. 한편, 복합트러스 교량의 복부 개방구조는 프리스트레스 박스교량에 비해 비틀림 성능을 저하시키는 단점을 가지고 있어 편심하중을 받는 교량이나 곡선교 등에는 아직까지 적용된 사례가 없다. 따라서 복합트러스교가 보다 널리 사용되기 위해서는 비틀림 거동에 대한 정확한 분석이 필요한 상황이다. 기존 연구에서는 복합트러스교의 격점구조형식에 따른 비틀림 거동 특성을 알아보기 위해서 3가지 형태의 박스형 복합트러스 실험체를 제작하여 그 거동을 분석하였다. 이에 이 연구에서는 기존연구를 바탕으로 유한요소 해석프로그램을 이용하여 실험체를 모델링하고 시뮬레이션을 통해 그 거동을 분석하여 해석적으로 검증해 보았다.