• Proceedings of the KSME Conference
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• 2003.04a
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• pp.409-414
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• 2003

Power steering hose is device that operation oil passes between steering gear box and oil pump by parts that is used to do steering system. Because this hose is receiving heat and pressure of high temperature, leakage can produce swaging from hitch of steel materials of done part. In this paper, we analyze swaging process of Power steering hose by finite element analysis, and achieved thermal and pressure analysis with this shape. We can analogize weakness part of hose through this result, and examine closely oil leakage and rubber failure mechanism and look for important design benevolence of power steering hose development.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.9 s.180
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• pp.2252-2258
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• 2000

In order to investigate the effect of nozzle on stress concentration in pressure vessels, three dimensional finite element analyses were performed. The results were compared with those for corresponding two dimensional axisymmetric finite element analyses. A three dimensional finite element model with a surface crack was also designed to evaluate the effect of internal pressure and heat transfer on crack face, and the resulting stress intensity factors from the finite element analyses were compared with those for ASME Sec. XI and Raju-Newman's stress intensity factor solution. As a result, the validity of currently available stress intensity factor solutions for a surface crack was reviewed in the presence of geometrical complexity, heat transfer and internal pressure.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.299-304
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• 2008

This paper presents plastic limit loads of piping branch junctions with local wall thinning under combined pressure and in-plane bending, based on systematic three-dimensional finite element limit analyses using elastic-perfectly plastic materials. An ideal branch junction without weld or reinforcement around the intersection is considered with two locations of wall thinning; one in the run pipe, and the other in the branch pipe. Based on FE results, effects of thinning geometries on plastic limit moments are quantified and simple approximations of plastic limit loads are proposed.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.1016-1021
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• 2005

A piezoresistive pressure sensor using a silicone rubber membrane has been fabricated on the selectively diffused (100)-oriented n/n+/n silicon substrates by a unique silicon micromachining technique using porous silicon ething. The width, length and thickness of the beam were 120${\mu}m$, 600${\mu}m$ and 7${\mu}m$, respectively and the thickness of the silicone rubber membrane was 40${\mu}m$. By the fusion of silicon beam and silicone rubber membrane, the mechanical strength of the pressure sensor could be highly improved due to smaller shear stress. The effectiveness of the sensor was confirmed through an experiment and FEM simulation in which the pressure sensor was characterized.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.603-607
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• 2002

Cavity pressure is a factor of what is occurring inside the mold and is used as one of the process parameters that control the overall injection molding cycle. The insight of cavity pressure is able to predict part quality and optimum process condition. In this paper, it is adapted ejector pin sensor to measure the cavity pressure and investigates the flow balance and the cavity pressure according to different runner thickness for adjusting the flow balance. Flow balance is very important to have not the poor results such as flash and warpage in the family mold. This paper predicted flow balance and cavity pressure using CAE analysis tool and compared with the test results. The results of analysis and test have a good agreement with the cavity pressure profile and flow pattern of the test.

• The Korean Journal of Zoology
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• v.34 no.1
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• pp.8-19
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• 1991

Atrial natriuretic peptide(ANP)의 유리기전에 대한 특성을 알아보고자, 흰쥐의 적출심장 관류모형을 사용하여 연구한 바 다음과 같은 결과를 얻었다. 1. 심방을 확장시켰을 때 ANP의 유리는 촉진되었다. 그러나 과용량을 부하하면 확장기간보다 회복기간에 ANP의 유리가 현저하게 증가하였다. 2. Epinephrine과 phenylephrine을 주입하면 ANP의 유리 량이 증가했으나, isoproterenol을 주입하면 심박수와 우심방 내압이 현저하게 증가했는데도 ANP의 유리량은 오히려 감소하였다 3. 미주신경을 자극하면 심박수의 현저한 감소에도 불구하고 ANP의 유리량은 증가하였다. 이상과 같은 결과에서 볼 때 결론적으로, 심방의 용량부하에 의해 심방근의 신장수용체가 자극을 받아 ANP의 유리가 촉진되는 것은 분명하고, 심방근이 확장할 때 보다는 확장 후 다시 원래의 길이로 환원될 때 ANP가 유리될 것으로 사료된다. 그리고 ANP의 유리에 대한 adrenergic조절은 o-receptor가 관련되어 있으며 심박수와 심방내압이 ANP의 유리를 변화시키는 데는 반드시 필수적인 인자가 아닌 것으로 여겨진다. 또한 특히 미주신경의 자극으로도 ANP의 유리가 조절될 수 있다는 것이 본 연구를 통해 새로이 발견되었다.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.268-273
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• 2004

This study is conducted to clarify the effect of internal pressure on the deformation and collapse behaviors of wall thinned elbow under in-plane bending moment. Thus the nonlinear three-dmensional finite element analyses were performed to obtain the moment-rotation curve of elbow contatining various wall thinning defects located at intrados and extrados under in-plane bending (closing and opening modes) with internal pressure of $0{\sim}15MPa.$ From the results of analysis, the effect of internal of collapse moment of elbow on the global deformation behavior of wall thinned elbow was discussed, and the dependence of collapse moment of elbow on the magnitude of internal pressure was investigated under different loading mode, defect location, and defect shape.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.6
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• pp.549-555
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• 2009

Based on three-dimensional(3-D) finite element limit analyses, this paper provides limit and TES (Twice-Plastic Load) loads for mitred pipe bends under bending and pressure. The plastic limit loads are determined from FE limit analyses based on elastic-perfectly-plastic materials using the small and large geometry change option. A wide range of parameters related to the mitred bend geometry is considered. Based on the finite element results, closed-form approximations of plastic limit and TES plastic load solutions for mitred pipe bends under bending are proposed.

• Aerospace Engineering and Technology
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• v.12 no.1
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• pp.81-86
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• 2013

This article deals with the manufacturing and performance evaluation on the specimen pipes which have large size diameter and thin thickness. This specimen is for LOX main pipe of KSLV-II propulsion feeding system. The material of specimen is alloy 21-6-9. Alloy 21-6-9 has higher strength and better weldability rather than STS-300 class pipes. We found that the specimen using alloy 21-6-9 satisfied the requirement by pressurization tests.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1996.04a
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• pp.82-82
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• 1996

후두전적출술은 상부 소화관의 연속성을 변형시킴으로써, 식도운동의 장애를 가져올 수 있으며, 술 후에 연하곤란을 호소하는 경우는 10% 가량 된다. 본 연구의 목적은 식도내압검사를 통하여, 후두전적출술이 상부식도괄약근의 휴지기와 최대 압력에 어떠한 변화를 주는가 및 술 후 인두와 상부식도괄약근의 조화성 여부와, 만일 상부식도괄약근의 기능에 변화가 생긴다면, 그 영향이 식도체부 및 하부식도괄약근의 운동성에 어떠한 영향을 주는지를 알아보기 위함이다. 식도내압검사는 8개의 내관을 가진 폴리에틸렌 도관으로, 후두전적출술을 받은 환자군 14명과 정상인 12명을 대상으로, stational pull-through 방법으로 시행하였다. 환자군에서 상부 식도괄약근은, 휴지기 압력, 최대 수축압력, 이완정도, 괄략운동의 조화성 및 괄약근의 길이 등이, 정상 대조군 보다 의미있게 감소되었다. 환자군에 있어서 식도체부의 운동성은 주로 근위부 식도체부에서, 수축력, 수축기간 및 연동파의 전파시간이 대조군에 비하여 의미있게 감소되었고, 연동운동시 동시 수축도 3례에서 관찰되었다. 하부 식도괄약근의 기능은 환자군과 대조군이 의미있는 차이를 보이지 않았다.