• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1057-1064
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• 2004

For New In-Cheon Airport. South Approach Section of Young long Great Bridge is to be special concerned to CWR due to substructure was already constructed former railroad bridge design specification. So we applied maintenance free system and CWR (Continuous Welded Rail) by ZLR(Zero Longitudinal Restraint) at bridge expansion joint part. This thesis generally introduce for CWR by ZLR at South Approach Section of Young long Great Bridge.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1410-1412
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• 1999

Protective relay for transformer operates in general by comparing with the differential current and the restraint current. These kinds of currents are changed on magnitude and phasor during the fault according to winding type and vector group. This paper presents the differential and restraint currents and operational principle of differential protective relay for two-winding and three-winding transformer with graphical model. It is developed using MATLAB for an educational purpose on engineer related in power system and protection in university and power utility including large factory.

• Steel and Composite Structures
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• 제1권1호
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• pp.145-158
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• 2001

An experimental study was conducted to evaluate the effects of loading sequence and lateral bracing on the behavior of reduced beam section (RBS) steel moment frame connections. Four full-scale moment connections were cyclically tested-two with a standard loading history and the other two with a near-fault loading history. All specimens reached at least 0.03 radian of plastic rotation without brittle fracture of the beam flange groove welds. Two specimens tested with the nearfault loading protocol reached at least 0.05 radian of plastic rotation, and both experienced smaller buckling amplitudes at comparable drift levels. Energy dissipation capacities were insensitive to the types of loading protocol used. Adding a lateral bracing near the RBS region produced a higher plastic rotation; the strength degradation and buckling amplitude were reduced. A non-linear finite element analysis of a one-and-a-half-bay beam-column subassembly was also conducted to study the system restraint effect. The study showed that the axial restraint of the beam could significantly reduce the strength degradation and buckling amplitude at higher deformation levels.

• 항공우주시스템공학회지
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• 제12권6호
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• pp.41-49
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• 2018

이번 연구에서는 복합재료 박벽보(thin-walled beam)에서 시위 방향으로 단일 셀의 비대칭성 단면을 가지는 모델을 선정하여, 단면의 형상에 대한 이론적인 동특성을 연구하였다. 이를 위해 전단 변형 효과(transverse shear effect)와 와핑 구속 효과(warping restraint effect), 보의 길이 방향으로 일정한 테이퍼비와 기하학적 단면비 등을 고려하고, 비대칭 단면의 와핑 함수 보정을 통해 수학적 모델링을 수행하였다. 그 결과에 따라, 고려한 단면의 질량 계수와 강성 계수 및 고유 진동수 등의 특성을 조사하였다. 특히, 단면의 비대칭성, 와핑 함수를 보정하지 않은 경우, 모델의 테이퍼비와 단면비 등이 고유 진동수에 미치는 영향을 비교 분석하였다.

• Korean Journal of Acupuncture
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• 제21권4호
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• pp.101-115
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• 2004

Objective : The present studies investigated the effects of 120 Hz high frequency electroacupuncture (EA) on the stress-induced stomach dysfunction in relation to its effect on the level of stress hormones and gastric mucosal damages. The gastric mucosal injury was induced by cold-restraint stress and two acupoints corresponding to Zusanli and Sanyinjiao in man were used. Methods : Cold-restraint stress produced typical gastric lesions in all rats of the stressed groups, but the number of ulcers as well as the mean ulcer diameter were reduced by 120 Hz EA pre-treatment. Results : The degranulation value of gastric mast cell was significantly higher in cold-restrained rats than in control ones. However, with the significant reduction of degranulation values of gastric mast cells in EA pre-treated rats compared with cold-restrained rats. Cold-restarint stress induced an elevated mRNA expression of pro-inflammatory gene such as cyclooxygenases-2 and tumor necrosis factor $(TNF)-{\alpha}$, but these expression were down-regulated in EA pre-treated rats. Immunohistochemical analysis showed that while the $inhibitory-{\kappa}B{\alpha}$ and $TNF-{\alpha}$ immunorection in the surface epithelium of the stomach tended to increase, both reactions in the EA pre-treated rats showed similar pattern as observed in controls. Conclusion : These results suggest that 120 Hz EA may act as a therapeutical means for gastric mucosal damages through an activation of pituitary adrenal system. It could be concluded that 120 Hz high frequency electroaucupuncture affords a good protective potential against stress-induced gastrointestinal dysfunction.

• Journal of Welding and Joining
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• 제33권6호
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• pp.6-12
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• 2015

Thermal fatigue life of the automobile exhaust manifold is directly affected by the restraint force according to the structure of exhaust system and bead shape of the welded joints. In the present study, the microstructural changes and precipitation behavior during thermal fatigue cycle of the 18wt% Cr ferritic stainless steel weld heat affected zone (HAZ) considering restraint stress were investigated. The simulation of weld HAZ and thermal fatigue test were carried out using a metal thermal cycle simulator under complete constraint force in the static jig. The change of the restraint stress on the weld HAZ was simulated by changing the shape of notch in the specimen considering the stress concentration factor. Thermal fatigue properties of the weld HAZ were deteriorated during cyclic heating and cooling in the temperature range of $200^{\circ}C$ to $900^{\circ}C$ due to the decrease of Nb content in solid solution and coarsening of MX type precipitates, laves phase, $M_6C$ with coarsening of grain and softening of the matrix. As the restraint stress on the specimen increased, the thermal fatigue life was decreased by dynamic precipitation and rapid coarsening of the precipitates.

• 오토저널
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• 제23권6호
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• pp.12-20
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• 2001

• Applied Microscopy
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• 제38권3호
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• pp.213-219
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• 2008

신경계통의 가소성은 신경세포의 변화에 의해 이루어질 뿐 아니라 신경아교세포의 변화에 의해서도 이루어진다. 신경아교세포 중 별아교세포는 신경세포의 기능을 조절하므로 정상적인 뇌의 기능을 유지하는데 매우 중요하다. 뇌에서 편도복합체는 위험 혹은 유해한 일련의 감각정보를 받아들이는 구역으로 받아들인 일련의 이와 같은 정보를 통합하고 변환시켜 공포라는 감정을 만들어낸다. 이런 과정은 편도복합체 신경세포에서 분비되는 신경전달물질의 균형변화에 의해 이루어지며, 신경전달물질의 조절에 별아교세포가 관여하므로 본 연구에서는 출생 전 스트레스와 성장 후에 받은 스트레스가 편도복합체 별아교세포의 세포체에 어떤 영향을 미치는지 조사하였다. 이를 위해 흰쥐를 스트레스를 받지 않은 대조군 (CON), 성장 후 스트레스를 받은 군 (CONR), 출생 전 스트레스를 받은 군 (PNS), 출생 전 스트레스와 성장 후 스트레스를 모두 받은 군 (PNSR)으로 구분하였다. 별아교세포는 GFAP 항체를 이용한 면역조직화학 염색을 시행하여 확인하였으며, methylene blue/azure II로 대조 염색하였다. Neurolucida 프로그램을 이용하여 계측한 별아교세포의 세포체는 일부 편도복합체 신경핵에서 출생 전 스트레스를 받은 PNS군이 대조군에 비하여 면적이 증가하였으며, 이런 경향은 출생 전 스트레스를 받고 다시 성장 후 스트레스를 받은 PNSR군에서 더욱 증가하였다. 따라서 흰쥐의 편도복합체에 분포하는 별아교세포는 스트레스에 영향을 받아 비대해지는 경향을 보인 것으로 나타났으며, 출생 전 스트레스가 성장 후에도 영향을 미치는 것으로 사료된다.

• 항공우주기술
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• 제11권1호
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• pp.7-18
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• 2012

국내 최초의 인증용 민수 항공기(KC-100) 개발을 위하여 수행한 전기체 정적구조시험에 대하여 소개하였다. 구체적인 내용으로는 시험요구도, 시험프레임, 주요 시험장치들인 하중 부가장치, 중량보상장치, 시험체 자세구속장치 및 잭킹 장치에 대하여 자세하게 설명하였고 특히 하중작용을 정확하게 부가하기 위하여 시험체의 설치와 하중부가치구의 설치에 대한 합치성을 보이는 과정을 자세하게 소개하였다. 전기체 하중시험 15가지와 국부하중시험 7가지 총 22가지 시험조건에 대하여 성공적으로 시험 수행하였고 시험 데이타들을 확보하였다.

• 자동차안전학회지
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• 제9권3호
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• pp.31-38
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• 2017

For years, Q1.5 (anthropomorphic test device for 1.5 years old infant) and Q3 (anthropomorphic test device for 3 years old infant) dummy protection has been improved considerably by the effort of EuroNCAP. ISOFIX strength of vehicle structure has increased and many child occupant protection tests have made child restraint system (hereafter CRS) optimized for child safety. However, from 2016, EuroNCAP changed the dummy which is used for the child occupant protection from Q1.5/Q3 to Q6/Q10 and these were also adopted in KNCAP from 2017. Therefore, a new method is required to secure the safety for older children In this research, child dummies were tested by using adult safety systems, and the different results from each adult restraint system were compared. Finally, dummies were tested with the CRS harness belt commonly used for infants, which has yielded significant result. In this research, mid-sized sedan and small SUV were used for the test. The researchers of this paper performed sled tests to correlate between the different adult safety belt system and child injury. Following the sled test, an actual vehicle test was conducted to gather the injury data of Q-dummy with the CRS harness belts. This paper will show the advantages of applying a pre-tensioner in the second row for child protection and the necessity of CRS which has its own harness belts to improve safety for older children.