• 한국해양공학회지
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• 제15권2호
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• pp.120-123
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• 2001

Despite the increasing necessity of accurate estimation of ring-stiffened cylinders'ultimate strength, the complex structural behavior of cylinders has made their design mainly depend on empirical formulas mostly based on limited test data rather than theoretical background. This paper has developed the imperfection method which enables the ultimate strength analysis of buckling-sensitive structures by combining two separate functions covered by common commercial finite element softwares, which are linear elastic buckling analysis and nonlinear stress analysis. Developed method was applied to two of the world most renowned softwares, MSC/NASTRAN and ABAQUS, for the analysis of ring-stiffened cylinders and unexpectedly big difference in their analysis results was found. This tells that many widely used commercial softwares have their different strong points and weak points and the choice of commercial software should be cautiously made after thorough inspection. This paper ends with some useful information about which of the two aforementioned softwares is more respectively for the linear elastic buckling analysis and the ultimate strength analysis of ring-stiffened cylinders.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 A
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• pp.158-160
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• 1998

This paper proposed the 2-D Finite Element analysis method taking into end-ring of squirrel cage induction motor. Secondary conductor resistance can be simply replaced new one considering end-ring resistance. In the case of 2-D FEM, the end-ring resistance is hard to condsider. And the results without considering end-ring resistance have an error. To verify the proposed method we compared the analysis results and test ones.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.901-902
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• 2011

• 한국산학기술학회논문지
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• 제14권8호
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• pp.3650-3655
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• 2013

파인블랭킹 금형을 제작하는 주목적은 전단면의 크기를 최대가 되도록 하기 위함이다. 본 연구에서는 전단면의 크기에 가장 크게 영향을 미치는 클리어런스는 재료 두께의 1%로 고정시키고 전단라인에서 Vee-Ring 중심까지의 거리 변화, V-Ring 각도의 변화, 전단 속도를 변화시키면서 전단 면적의 크기 변화를 연구 고찰하였다. 각 실험으로부터 시편을 채취하여 전단면의 크기를 분석한 결과 V-링의 거리는 2mm, 각도는 외측$45^{\circ}$/내측$30^{\circ}$일 때, 전단 속도는 6.4m/min일 때 전단면의 크기가 가장 크게 됨을 알 수 있었다.

• 대한안전경영과학회지
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• 제2권4호
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• pp.197-208
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• 2000

ABS sensor ring has been manufactured by powder metallurgy (P/M) method using 400 series ferrite stainless steel. The results are following. It is supposedly sufficient to use for control computer due to good experimental results of magnetic characteristics. Compared with sensor ring made by iron, 400 series ferrite stainless steel has shown a good corrosion resistance without an addition surface treatment. Thus the decreasing production process has been obtained. As a result mechanical characteristics of hardness and tensile test, 400 series ferrite stainless steel shown a good endurance when it is combined to constant velocity joint(C/V), and has a good hardness properties endurable to sand and pebble impact. The products before sintering are much more corrodible in the condition of spray test of salt water and ammonia than humidity and nitrogen condition.

• Journal of Welding and Joining
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• 제32권5호
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• pp.1-6
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• 2014

This study aims at manufacturing SA welded API-X70 line-pipe with sour gas resistance. A pipe was manufactured by JCO bending process and SA welding using the API-X70 plate guaranteed HIC resistance. SA welded pipe was expanded in order to reduce the residual stress. The evaluation of a pipe for resistance to HIC and SSCC were performed by the RS D 0004 and RS D 0005 standards. For verification that a pipe has acceptable resistance to HIC, fullscale test was carried out. Results showed no cracking for the HIC and SSCC.

• 대한안전경영과학회지
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• 제5권1호
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• pp.129-141
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• 2003

In this thesis, using the 400 series ferrite stainless steel such as 434LD$_2$ which are furter excellent then the existing ferric products in mechanical characteristics, and experiment has been conducted on corrosion resistance of sensor ring. The results are following. 1. The products before sintering are much more corrodible in the condition of spray test of salt water and ammonia than humidity and nitrogen condition. 2. 434LD$_2$ ferrite stainless steel has shown a good corrosion resistance without an addition surface treatment. thus the decreasing production process has been obtained. 3. As hardness value of $H_{RB}$ 80 and tensile test, 434LD$_2$ ferrite stainless steel with show a good endurance when it is combined to constant velocity joint (c/v joint), and has a good hardness properties endurable to sand and pebble impact.

• 콘크리트학회논문집
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• 제11권4호
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• pp.129-136
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• 1999

For the prediction of concrete-steel bond ability in reinforced concrete, many countries establish specifications for the pullout test. But these methods hardly to consider many parameters such as strength, shape, diameter and location of steel, concrete restrict condition by loading plate, strength of concrete and cover depth etc, and it is difficult to solve concentration and disturbance of stress. The purpose of this study is to propose a New Ring Test method which can be rational quantity evaluations of bond splitting mechanism. For this purpose, pullout test was carried out to assess the effect of several variables on bond splitting properties between reinforcing bar and concrete. Key variables are concrete compressive strength, concrete cover, bar diameter and rib spacing. Failure mode was examined and maximum bond stress-slip relationships were presented to show the effect of above variables. As the result, it appropriately expressed general characteristics of bond splitting mechanism, and it proved capability for standard test method.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1994년도 교수 연수회(역학)
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• pp.142-149
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• 1994

Substitution of graphic representation for extensive lists of numerical statistical data is highly desirable by both editors and readers of medical journals, faced with an exploding abundance of contemporary medical literature. A novel graphic tool. the 'double-ring diagram', is described herein which permits visual representation of information regarding certain statistical variables used to describe the performance of a test or physical sign in the diagnosis of a disease. The diagram is relatively easy to construct on the basis of a number of primary data such as the prevalence and the true positive, true negative. false positive and false negative test results. These values are reflected in the diagram along with the values of other statistical variables derived from them. such as the sensitivity. specificity, predictive values for positive and negative test result. and accuracy. This diagram may be useful in visualizing a test's performance and facilitating visual comparison of performance of two or more tests.

• 한국콘텐츠학회논문지
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• 제12권9호
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• pp.182-193
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• 2012

벨소리와 통화연결음 시장의 확대에 주목하여 음원소비가 감상용 음원에서 꾸미기용 음원으로의 활용 확대되는 시점에서 발신자와 수신자가 음원에 대하여 브랜드개성으로 인식하는지, 자아표현이 어떠한 방식으로 이루어 질 것인가에 관한 연구이다. 대학생 196명을 대상으로 본인의 자아이미지와 본인이 선택 혹은 선택 예정인 벨소리와 통화연결음이 일치하는지에 대한 설문조사를 실시하였다. 표본을 대상으로 SPSS 19.0 통계패키지를 사용하여 대응표본 t테스트를 실시한 결과 자아이미지의 요인으로 도출된 내향성, 외향성과 벨소리, 통화연결음의 요인으로 도출된 내향성과 외향성의 관계가 서로 불일치하였다. 즉 내향성을 가진 소비자는 외향적인 음원을, 외향적인 소비자는 내향적인 음원을 선택하고 있었다. 휴대전화 발신자는 벨소리와 통화연결음 등 음원을 선택함에 있어 본인이 아닌 상대방을 염두에 두어 본인의 자아이미지와 상반되는 브랜드개성을 가진 음원을 선택하는 즉 과시적 소비성향을 보여주고 있다.