• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.218-223
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• 2017

본 논문은 75톤급 액체로켓엔진의 상태진단을 위해 칼만 필터를 이용한 고장진단 연구를 수행하였다. 칼만 필터 설계를 위해 75톤급 액체로켓엔진 비선형 시뮬레이션 모델을 공칭 작동점에서 선형화하였으며, 정상 모델의 상태량 변수 4가지를 이용하여 측정값과 추정값 비교를 통해 칼만 필터의 성능을 확인하였다. 이를 이용한 고장진단 알고리즘의 성능을 확인하기 위하여 터보펌프 고장을 모사하였으며 정상 모델의 잔차 변화를 비교하여 칼만 필터를 이용한 고장진단이 가능함을 확인하였다.

• 대한정형도수물리치료학회지
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• 제27권2호
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• pp.37-43
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• 2021

Background: The purpose of this study is to compare and analysis the changes in strength and endurance of the knee extensor muscles after Anterior cruciate ligament reconstruction. Methods: Twelve male subjects with ligament injury were seated on Biodex and the hip joint was flexed at 110°, and torso, lower extremities, and legs were fixed using Velcro. The resistance device was placed at a point 3cm above the ankle, and measurements were taken before and a surgery at 60°/sec and 180°/sec when the knee was maximally extended. The postures ingeniously combine forward-bending poses countered with backward-bending ones. Results: There was no significant difference in the comparison of muscle strength of 60°/sec and 180°/sec before surgery. But there was a significant difference after surgery. There was significant difference in muscle endurance both before and after surgery. There was a significant difference in the pre- and post- operative comparison values of muscle strength and endurance in isokinetic movements at 60°/sec and 180°/sec during knee extension on the injured side. Conclusion: For cruciate ligament tears, Orthopedic reconstruction is recommended. Correct alignment of the knee ligament after surgery can enhance the strength and endurance of the quadriceps femoris during knee extension rejuvenated.

• 대한정형도수물리치료학회지
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• 제28권1호
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• pp.53-60
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• 2022

Background: The aim of the study is to examine whether mediating or moderating effects of stress between teachers' work environment and work-related musculoskeletal disorders. Methods: Two hundred nine participants took part in the study and completed the surveys including work environment, stress and work-related musculoskeletal disorders questionnaires. Hayes's PROCESS macro was used to test the research models for mediating and moderating effects of stress between work environment with teachers and work-related musculoskeletal disorders. Indirect effect was tested using bootstrapped confidence intervals. Results: The result confirmed that Stress served as a indirect mediator between work environment and work-related musculoskeletal disorders, whereas there was no significant the moderating effect. Conclusion: Stress mediates the relationship between work environment and work-related musculoskeletal disorders. Therefore, it is crucial that teachers' work environment that increases stress should be enhanced to reduce work-related musculoskeletal disorders.

• 항공우주시스템공학회지
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• 제11권3호
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• pp.31-38
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• 2017

항공 산업의 소비 수요가 증가함에 따라 국내에서 수행할 수 있는 인증체계 및 비행시험 운영에 필요한 연구가 요구된다. 이에 따라 본 논문에서는 국내 민항기 KC-100, 군용기 T-50 사례와 국외 FAA(Federal Aviation Administration), CAAC(Civil Aviation Administration of China) 기관의 비행시험 관련 문건을 바탕으로 개발 및 개조 중에 있는 항공기에 대한 성능검증, 시험평가 및 안전성 인증을 위한 비행시험 운영 절차와 안전 관리 프로그램 개발 연구를 수행하였다. 또한 항공기 비행시험 절차에 적용할 수 있는 FTSC(Flight Test Safety Committee)의 모범사례(Best Practices)를 조사 분석하였다.

• 항공우주시스템공학회지
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• 제11권3호
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• pp.22-30
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• 2017

본 논문은 액체로켓엔진의 건전성 감시 및 관리기법에 대한 연구 동향을 소개한다. 이를 위하여 실제 액체로켓엔진에 연구 및 적용되었던 고장진단 알고리즘을 조사하였다. 특히 한국형발사체(Korea Space Launch Vehicle II, KSLV-II)에 적용하기 위해 한국형발사체 로켓엔진과 같은 구조인 개방형 액체로켓 엔진에 적용된 알고리즘을 조사하였다. 이러한 과정을 통해 적용된 사례들의 특징을 따로 세분화하고, 한국형발사체 로켓엔진과 비슷한 중국의 개방형 액체로켓엔진들의 고장진단 기법 특징들을 분석하였다. 나아가 2019년에 발사를 목표로 하는 한국형발사체에 적용시키기 위해 고려해야 할 사항에 대하여 토론하고자 한다.

• 구강회복응용과학지
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• 제31권1호
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• pp.20-25
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• 2015

목적: 이 실험의 목적은 장석계 도재에 항균성을 부여하기 위해 은을 다양한 농도로 첨가하였을 때, 은 첨가가 장석계 도재의 색조에 영향을 미치는지 알아보기 위함이다. 연구 재료 및 방법: 대조군은 은을 포함하지 않은 일반 장석계 도재를 이용하고, 은이 5%, 10%, 20%, 30%의 농도로 첨가된 장석계 도재를 4개의 실험군으로 하여 총 5개의 그룹을 이용하였고, 각 그룹당 각 5개씩 디스크 형태로 시편을 제작하였다. 각 시편은 색차계를 이용하여 L, a, b값을 2번씩 측정하였다. 각 값은 SPSS를 이용하여 일원분산 통계 분석을 시행하였다. 결과: 은의 함량이 높아짐에 따라 각 그룹간 L값은 거의 비슷하였고, a값은 점차 증가하고, b값은 점점 감소하는 양상을 보여주었다. 은의 함량이 높아짐에 따라 ${\Delta}E$ 값은 유의하게 증가하였다. 5% 은 이온이 함유된 도재와 10%의 은 이온이 함유된 도재는 ${\Delta}E$값이 3.7 이하였다. 결론: 장석계 도재에 은을 첨가하는 것은 도재의 색조에 영향을 준다. 하지만 10% 이하의 이온을 첨가한 장석계 도재는 임상적으로 받아들여질만 하다.

• 한국주조공학회지
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• 제21권6호
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• pp.336-342
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• 2001

This study was carried out to examine the effects of adding 0.3at.%Hf in Fe-30at.%Al-5at.%Cr alloy on the variation of microstructures and hot workability. The effect of hot rolling on mechanical properties was estimated by measuring the elongation and tensile strength after rolling at 800 and 1000 respectively. Microstructure of Fe-30at.%Al-5at.%Cr alloy was consisted of large equiaxed grains and it was changed to quasi-equiaxed or columnar structures by adding 0.3at.%Hf to Fe-30at.%Al-5at.%Cr alloy. Every specimens showed a decreased tensile strength after hot rolling compared to that of before rolling. The elongation was increased by hot rolling. Remarkable changes in elongation by hot rollong was observed such as from 1.4% to 4.5% elongation at the specimen of 0.3at.%Hf added to Fe-30at.%Al-5at.%Cr. Fe-30at.%Al-5at.%Cr alloy showed typical cleavage fracture on tensile failure and hot rolling has negligible effects on fracture mode in this alloy. However at the alloy containing Hf fracture mode was changed by hot rolling from intergranular to mixed intergranular and transgranular fracture mode.

• 열처리공학회지
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• 제18권2호
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• pp.91-98
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• 2005

Both commercially pure titanium and Ti-6Al-4V alloy have been widely used as biomaterials because of their excellent biocompatibility, corrosion resistance and mechanical properties. However, in recent years, vanadium has been found to cause cytotoxic effects and adverse tissue reactions, while aluminium has been associated with potential neurological disorders. A newly designed ${\alpha}+{\beta}$ type Ti alloy, Ti-10Ta-10Nb alloy showed superior properties to CP Ti and Ti-6Al-4V alloy in the point of biomaterial, and elucidated the future uses as a biomaterial. Microstructural changes of Ti-10Ta-10Nb alloy after hot-rolling, warm-rolling, solution and aging treatment were investigated. According to TEM results, the microstructures after solution treatment were composed of mostly ${\alpha}$ phase with a trace of ${\beta}$ phase due to adding ${\beta}$-phase stabilizer tantalum and niobium. The microstructures after warm-rolling is coarse and elongated ${\alpha}$ phase and hot rolling resulted in very fine ${\alpha}$ widmanst$\ddot{a}$tten. The highest value of hardness was obtained by aging treatment at $400^{\circ}C$ for 20hr in which microstructure consisted of very fine ${\alpha}$ phase in ${\beta}$ matrix.

• 대한한의학방제학회지
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• 제20권2호
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• pp.117-136
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• 2012

This thesis is the study on GuiLinGuBen "ShangHanZaBingLun"'s prescriptions which are totally 324, and unique 91 which are not written in current "ShangHanZaBingLun" and "JinKuiYaoLue", only in GuiLinGuBen "ShangHanZaBingLun". For modern clinacal effectiveness of GuiLinGuBen "ShangHanZaBingLun", this thesis clarifies the prescriptions' distinction between GuiLinGuBen, "ShangHanZaBingLun" and "JinKuiYaoLue". First it classifies prescriptions into 4 groups, which are only in GuiLinGuBen, in "ShangHanZaBingLun", in "JinKuiYaoLue", and in both "ShangHanZaBingLun" and "JinKuiYaoLue". Second it tabulates and describes in detail GuiLinGuBen's prescriptions about title, prescription composition, prescription volumetrin, decotion, and dosage. Third it catches distinctive characteristic of GuiLinGuBen's prescriptions by a comparative study which clarifies the differences of prescriptions between GuiLinGuBen, "ShangHanZaBingLun" and "JinKuiYaoLue". Current "ShangHanZaBingLun" and "JinKuiYaoLue"'s remedy focus on Shanghan and Jabbyong, so it has no choice but to have large remedy vaccum. The prescriptions only in GuiLinGuBen have same system with "ShangHanZaBingLun" and "JinKuiYaoLue"'s prescriptions, and contain unique Fever remover(淸熱劑) and Counterbalancer (補劑), so they could give more clinacal practice over "ShangHanZaBingLun" and "JinKuiYaoLue".

• 한국도서관정보학회지
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• 제28권
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• pp.415-445
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• 1998

This study attempts at the engraving place of wood-printing plates held in the Haein Temple(해인사), which were famous for playing the significant role in the understanding of publishing activities of both the Koryo and Choson Dynasty. Following the common way the bibliographic elements of the books were analyzed namely according to the publication place and the publisher. The findings derived from the analysis are summarized as follows; In the Haeinsa the wood-printing plates books are preserved moved from 17 temples such as Bongso-Sa(봉서사), Hago-Sa(하고사), Soksuam(석수암), Inhung-Sa(인흥사), Wonkwang-Sa(월광사), Sinha-Sa(신하사), Gunsyaeng-Sa(군생사), Jangsu-Sa(장수사), Yongtong-Sa(영통사), Wonjok-Sa(원적사), Unjin(은진) SSanggye-Sa(쌍계사), Songsan(성산) SSanggye-Sa(쌍계사), Hungyul-Sa(흥률사), Jongwon-Sa(정원사), Yon-Sa(연사), Gamro-Sa(감로사), Yongguam(영귀암) besides the publications of temples, there are publications of local branches of gangyengdogam(간경도감) such as Jinju(진주), Sangju(진주), Sangju(상주), Andong(안동), of local public agencies such as Gaelimbu(계림부), Dalsunggwan(달성관), and of private families of which 8 titles in the Koryo Dynasty and 13 titles of the Choson Dynasty. Among the "SSanggyae-Sa(쌍계사) publication" held in the Haeinsa, 9 titles including Chimungyonghun(치문경훈) are recklesaly preserved with dividing both in Gap temple(갑사) and in Haeinsa as the same publication. It is possible that other scattered present publications or remaining publications might have been remaining publication from those partly burnt ones of the complete publications. By means of the investigation on the catalogs of publications, 5 titles such as <> <> <> <> <> which are now kept in the Haeinsa moved from the Taegubu(대구부) or Yongyon-Sa(용연사) were newly identified.