• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.1071-1076
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• 2007

In high-speed line, at some part of the track which rubber ballast-mat installed, track irregularity grew rapidly and affected riding comfort and train running stability. It is urgently requested to establish counter-measures which can be applied to track under operation. To do this, it is very important to analysis the origin of that phenomenon before. Track support stiffness is an essential factor for evaluating track condition. Sudden changes of support stiffness along track occur instability of train and bad riding comfort. Preventing sudden changes of track support stiffness is a key technique in high-speed track maintenance. Besides the sudden changes, the magnitude itself also significantly affects track and train. Low stiffness of ballast-mat makes ballast acceleration area wider. And it may accelerate track irregularity growth. So, the stiffness should be limited. To calculate track stiffness, measuring load and displacement on track is needed. In this study, the behavior of the track which rubber ballast-mat installed was measured and analyzed to understand the origin of rapid growth of it.

• 품질경영학회지
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• 제25권1호
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• pp.135-141
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• 1997

The Copper-Clad Laminate (CCL) is a main electronic component of specialtype printed circuit boards (PCBs) such as Silver Through Hole PCB. This CCL should have high reliability under the aging test, and usually the test is done at a higher temperature (110-$150^{\circ}C$) than the normal. Then, this test condition of high temperature may cause such quality problems as hole eccentricity and reduction of distance between part holes. After measuring the CCL shrinkage affected by temperature, the correction factor of a press mold was a, pp.ied to solve these problems. The results showed that the tolerance of hole pitch(${\pm}$$100{\mu}m$) was satisfactory and the internal and external failure costs were reduced by 55%.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제28회 추계학술대회
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• pp.234-243
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• 1998

In this paper, thermite and gas pressure weldings have been used to join rails in-track and analyzed as functions of hardness and wear characteristics. The wear rate of thermite welded rail is low compared with that of gas pressure welded rail, which is tested in a pin-on-disk wear tester. The hardness of thermite welded materials is relatively high and narrow distributed between three zones, welded part, thermally affected zone, and a base matrix. Wear of a welded rail may be a major factor in railroad maintenance costs and failures at the rail-rail butt joint.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1998년도 춘계학술대회논문집
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• pp.32-35
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• 1998

The material properties and forrnabilities of tailored blanks are evaluated by experimental tests. In the tensile test, the gradient of strength coefficients of the heat affected zone associated with the welded line width represents the quality of a welded part. In the hemispherical dome punching test, the plane strain state of the welded line is observed. In the squared cupping test, the thin side is stretched more than the thick side in the stretch mode, while both sides are similarly stretched in the draw mode. In the 2D draw test, FLCo is measured in a simple manner and the forming defects of the tailored blanks with the same thickness are found.

• 한국주거학회논문집
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• 제4권1호
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• pp.5-16
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• 1993

This paper tries to find out the characteristics of the vernacular dwellings in Noksan area which has been a part of Kaya cultural realm. Through the analyses of its environments and several practical unit plans. The characteristic of the vernacular dwellings in thes arer are as below. The dwellings has been transfigured form [Omaksari] hut which is generally the smallest house form in Korea. The noticeable vernacular hut in this area is smallest 4-kan double-wing plan which is irregular 전 shape, but they call it single wing and 2-kan plan. Leed which can be obtained easily in thes area is used on roof and in wall. Timbers used in constrution are very slim or rather weak, but they were treated carafully. The chimney form in this area seems the results of minimizing of their being from the invasion of Japanese pirate, but also it seems an effective method of heat control. In conclusion, we cannot deny that the house form of this area seems affected by its exclusive natural and social environments.

• 산업공학
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• 제3권2호
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• pp.39-51
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• 1990

One of the most important and powerful tools available for design and/or study of the operation of complex systems and processes is simulation. Since automated material handling systems like AS/RS are often quite complex, a network-based simulation model is developed to analyze an automobile part supplier's automated storage and retrieval system(AS/RS). The network simulation model is implemented in the SLAM Ⅱ on a VAX 8800 computer. Performance of the AS/RS was tested for 3 dispatching rules, 3 work load levels, 2 storage policies, 3 levels of stacker crane break-down, and 2 conveyor system layouts. Results indicate that the AS/RS performance is primarily affected by the dispatching rule and work load level.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1999년도 학술대회논문집-국제 전기방전 및 플라즈마 심포지엄 Proceedings of 1999 KIIEE Annual Conference-International Symposium of Electrical Discharge and Plasma
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• pp.71-75
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• 1999

This paper describes the temperature characteristics and influence produced from the unification of Magnetic Ballast and simple Electronic starter for fluorescent lamp. This is affected by the transmitted Temperature from a part of Ballast loss in half-wave rectifier electronic starter. The simulation and experiment show that characteristics of capacitor in electronic starter is changed by the high temperature(80$^{\circ}C$) of magnetic ballast, and preheating time of lamp is reduced by it.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.1955-1960
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• 2014

Background: This study was performed to determine the experiences of nursing students in caring for paediatric cancer patients and their families. Materials and Methods: This qualitative survey was carried out with 14 students studying in the nursing department of the Faculty of Health Sciences of a university in Edirne, Turkey. Data were obtained through focus group interviews and evaluated based on a qualitative content analysis. Results: It was determined that students, for the most part, experienced problems related to communication, sadness, helplessness, fear, anxiety, resentment and anger. In addition, the students were affected most often by effects of the disease and invasive procedures on paediatric cancer patients and their families during the process of caring for them in the oncology clinic. Conclusions: It would be useful to inform nursing students, prior to clinical practice, about the special needs of paediatric cancer patients and families who stay in oncology clinics, and to follow up with appropriate guidance during the clinical practices.

• Asia pacific journal of information systems
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• 제9권2호
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• pp.99-115
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• 1999

Electronic Data Interchange (EDI) is an important part of interorganizational electronic commerce due to the strategic impact derived from its use. In order to ensure successful implementation of EDI, EDI controls must first be developed. Because they are implemented in an environmental context, the characteristics of organizational environments have a significant impact on EDI controls. The control strategy for the EDI system - formal, informal, and automated controls - should fit certain organizational environments. A research model has been developed to depict the moderating effects of six environmental variables including industry, organizational, and task characteristics on the relationships between controls and implementation. It is shown empirically that the relationships between EDI controls and implementation are indeed affected by these factors. The results can help management design formal, informal, and automated controls in view of their own environmental contexts.

• 대한기계학회논문집A
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• 제32권6호
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• pp.504-511
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• 2008

This study evaluated the influence of the strength mismatch of HAZ for a plastic ${\eta}$-factor, which is the principle parameter determining the plastic portion of J-integral to assess the fracture toughness of the weldment. The specimen of tensile and hardness test was manufactured from the piping applying narrow-gap welding, and the mechanical properties of weldment, HAZ and a base metal were obtained. To perform the finite element analysis according to the ratio of strength mismatch, the material properties was chosen with the change of strength using the determination method of Ramberg-Osgood constant. Also, the influence of the strength mismatch of HAZ was determined using finite element analysis by those properties.