아세아의 새로운 세력균형하의 한국과 미국

정진오 동국대학교 안보연구소 1976 安保硏究 Vol.- No.6

일제의 한국병합정책에 대한 연구

정진오 제주대학교 법과정책연구소 1996 法과 政策 Vol.- No.2

자동차용 브레이크 마찰재에서의 환원분철의 마찰특성에 관한 연구

정진오,이경환,김옥삼,김봉수 순천대학교 2000 순천대학교 자연과학논문집 Vol.19 No.1

In most automotive brakes, the friction material is used to convert the kinetic energy into heat. The friction material is a complex composite consisting of a resin, reinforcing fibers, lubricants and filler materials. In an attempt to enhance the friction performance of the friction material, a trial was done to examine the substitution of filler material by the reduction iron powder. In this study, two types of reduction powder M1 and M3 was prepared by the reduction process developed by Hanta M&B Inc. M1 and M3 which has reduction ratio of 1.5 and 92% respectively was used in place of BaSO_4, which was conventionally used as a filler material. The amount of M1 and M3 was varied as 10, 20, 30%, while the other component remains the same except the replaced BaSO_4. For those specimens with different amount of reduction iron powder, friction performance tests such as friction coefficient, rotor compatibility were conducted by using brake dynamometer. The bonding strength and hardness tend to decrease with use of M1 and M3, but specific weight decreased with increase of M1 and M3. The friction coefficient increased with use of M1 up to 10%, but decreased for use of M1 more than 20%. However the use of M3 resulted in a decrease of friction coefficient all the way. The surface roughness decreased with the use of M1 and M3, except for a case of excessive use of M1 of 30%. The rotor surface roughness did not show any correspondence with hardness of friction material in this study.

Regulation of hMSC behaviors on polycaprolactone/biphasic calcium phosphate composites scaffold for bone tissue engineering

정진오,최종배,정성인,신영민,권희정,박종석,임윤묵 한국고분자학회 2014 한국고분자학회 학술대회 연구논문 초록집 Vol.2014 No.4

격자형 구조물의 웹크립플링

정진오 順天大學校 1994 論文集 Vol.13 No.1

□A finite element analysis was performed to study the failure mechanism in the cell-type structure which consists of two skin flange plates and connecting web plates. Compressive patch loads of different boundary conditions were applied to the structure, and the web crippling damage mechanism and its characteristics were studied through analysis of strains and deflections as compared to the load. A load vs. horizontal deflection curve was intended to determine the load at which buckling initiated, but the deflection increased rather gradually due to initial imperfection of web. The strain measurements from each side of the web plate as a function of load showed a separation of the strains, which implied that the buckling triggered the web crippling. The distributions of compressive strains along a vertical line under the load patch showed a strain concentration in the upper regions of the web until ultimate load was reached, and a redistribution of the strain resulted in maximum strains at a certain depth of the web. These findings were in good agreement with the experimental results by Schneider et al. The distributions of the out-of plane deformation of the web changed with the boundary condition in patch load. The deformation mode in foundation load did not change, while in docking load the deformation mode showed a transition as the deformation progressed.

Development and characterization of heparin immobilized polycaprolactone/biphasic calcium phosphate composites scaffold for bone tissue engineering

정진오,최종배,정성인,신영민,권희정,박종석,임윤묵 한국고분자학회 2014 한국고분자학회 학술대회 연구논문 초록집 Vol.2014 No.4

원격장 와전류 배관 탐상 시스템 개발

정진오,이재경,김형진 한국비파괴검사학회 2001 한국비파괴검사학회지 Vol.21 No.5

배관의 관벽투과 특성을 지닌 원격장 와전류 비파괴 검사법은 열교환기 세관 검사에서부터 천연가스 수송관에 이르기까지 다양한 형태의 배관과 결함을 대상으로 적용 연구가 진행되고 있다. 공칭 외경 100㎜의 주철관은 주로 상수도 관로의 배수관으로 활용되고 있는데, 차량 진동과 부식에 의한 결합의 생성으로 정수의 누수 문제를 일으킨다. 그러나, 탐상 경제성 및 효용성 문제로 관내 검사장치 투입과 같은 직접적인 검사 방법의 수행이 제한되어 왔다. 원격장 와전류 방법은 시스템 구성이 용이하고, 내·외부 부식 결함에 대한 정량적인 평가가 가능하기 때문에 경제성 있는 장치 개발이 가능하다. 본 연구에서는 원격장 와전류 기술을 이용하여 상수도 관망의 특성을 고려한 매설 배관 검사시 스템 개발을 수행하였다. 세부적으로는 관내 투입 원격장 와전류 검사의 기구부 설계 및 제작, 원격장 와전류 신호의 획득 및 처리 프로그램 개발, 그리고 개발 장치의 운용 방법 및 절차 검토 등으로 되어 있다. Remote field eddy current testing (RFECT) with through-wall transmission characteristic is being applied to pipes ranging from small tubes of heat exchanger to natural gas supply pipelines. Cast iron popes with nominal diameter of 100㎜ are used primarily as the waterline pipes. The leakage of water occurs due to defects in the pipes caused by vibration of automobiles and corrosion. But, the use of direct inspection methods such as insertion of inspection equipment inside the pipelines has been limited due to its lack of economical efficiency. Economical development of inspection equipments is possible since RFECT method can be easily employed for system integration and quantitative evaluation of both inside and outside defects. In this study, the development of underground pipeline inspection system was carried out by using RFECT method in consideration of the characteristics of waterline network. This paper specifically describes the design and production of RFECT pipeline inspection pig using centralizer mechanism, development of remote field eddy current signal acquisition and processing software, and review of RFECT system operation procedures.

近代化 理論에 대한 硏究

鄭鎭午 제주대학교 1983 논문집 Vol.16 No.2

In study of theories of modernization, we need phenomenological approach. And the goal of modernization is commonly self-supporting economy. The material conditions of life must be accompanied by the spiritual elevation and most of the developing countries also need nationalism.

축 하중을 받는 Al/CFRP 혼성튜브의 압궤모드와 에너지흡수 특성에 관한 연구

정진오,양인영,차천석,이길성 대한기계학회 2004 大韓機械學會論文集A Vol.28 No.11

격자형 구조물의 웹 파손에 관한 유한요소해석

정진오 순천대학교 공업기술연구소 1994 工業技術硏究所論文集 Vol.8 No.-

A finite element analysis was performed using the non-linear program ADINA to determine the patch load carrying capacities of webs in the cellular structure which consists of two skin flanges and connection webs. Compressive patch loads of various lengths were applied to the flange directly over the webs, with non-rotational(foundation) or rotational(docking) boundary condition imposed. Eight-noded shell elements were used to model the 3-dimensional cell-type structure, and the buckling load and the ultimate load were sought for the webs with or without initial imperfections. The I-sections similar to the cell-type structure were analyzed together, and results were compared to the AISC design loads. The membrane action of the flanges in the cell-type structure was found not only to fix the movement of the web in its out-of-plane direction but also to give somewhat degree of non-rotational constraint. Thus, the membrane action gave the additional load carrying capacity to the similar I-sections. As the length of load patch increased, failure mode changed from web yielding to web crippling, and to web shear, as was expected from the AISC criteria for I-sections. The ultimate load of the cell-type structure followed the AISC design load for the I-section, but the ultimate load for the docking turned out to be much smaller than the ultimate load for the foundation. The buckling load was sensitive to the initial out-of-flatness of the web, but the ultimate load was not significantly influenced by the initial imperfections. The calculated ultimate loads in the present modelling were somewhat smaller than the AISC nominal strength, or test results by Schnider et al. This gap was considered to be attributable to the load patch which may increase the effective thickness of the flange in the test by several times.