http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
김상철,함경춘,강동명,Kim, Sang-Chul,Ham, Kyoung-Chun,Kang, Dong-Myeong 한국정밀공학회 1992 한국정밀공학회지 Vol. No.
The effect of mechanical, properties in the plastic zone near the crack-tip was investigated, under various controlled loading conditions, i.e., ${\Delta}K$ increasing, ${\Delta}K$ decreasing, and single overload test. For both ${\Delta}K$ decreasing test and ${\Delta}K$ increasing test with constant stress ratio, it is found that the ratio of material constant m'( ${\Delta}K$ decreasing test) to material constant m( ${\Delta}K$ increasing test) is larger than 1 for n<0.1, and it is equal to 1 for 0.1<n<0.2. But it is smaller than 1 for n>0.2. A modified crack growth rate equation based on Forman's equation which applied stable region of fatigue crack propagation in ${\Delta}K$ decreasing test is proposed. Within the limit of this single overload test, an empirical relation between among the retardation ratio (Nd/ $N^{*}$), the strain hardening exponent (n) and the percent peak load (%PL) has been established.established.
노즐 이종금속용접부의 내면 보수용접부에서 수치해석법을 이용한 PWSCC 균열성장해석
김상철,김만원,Kim, Sang-Chul,Kim, Mann-Won 대한용접접합학회 2011 대한용접·접합학회지 Vol.29 No.2
In this paper, crack propagation analyses in the inner diameter (ID) repair weld of the dissimilar metal weldment of a nozzle were performed using a finite element alternating method (FEAM). To calculate the theoretical solution for the crack tip stress intensity factor, a weak type singular integral equation consisted of crack surface traction and dislocation density function was constructed and solved in conjunction with the FEAM. A two-dimensional axisymmetric finite element nozzle model was prepared and ID repair welding was simulated. An initial crack, 10% depth of weld thickness, was assumed and crack propagation trajectory from the initial crack to the 75% depth of thickness was calculated using the FEAM. Crack growth versus time curve was also calculated and compared with the curves obtained from ASME code method. With the method constructed in this paper, crack propagation trajectory and crack growth time were calculated automatically and effectively.
헬리콥터 조종사의 상황인식과 교육 만족도의 상관분석을 통한 교육개선연구
김상철,이용혁,Kim, Sang-chul,Lee, Oyong-hyeok 한국항공운항학회 2021 한국항공운항학회지 Vol.29 No.1
The topic of this paper was analyzed as "t -test" and "multiple regression analysis" for 303 helicopter pilot trainees from aviation schools in the county for "improvement of education through correlation analysis of helicopter pilots' situational awareness and education satisfaction." In addition to the factors for overcoming situational awareness and situational awareness, the level of satisfaction of the instructor and the level of satisfaction of the learning management system (LMS) is the confidence interval p<.05, 95%. It was analyzed to be significant at the level of 05, 95%. Therefore, it was analyzed that in order to improve the "quality of the instructor" in future education, institutional supplementation and "learning management system (LMS)" need to be established including VR and AR so that pilot trainees can use it at all times.
대형시공사의 사업관리 역량 강화를 위한 교육 전략 수립에 관한 연구
김상철,박찬정,이상엽,손재호,Kim, Sang-Chul,Park, Chan-Jeong,Lee, Sang-Youb,Son, Jae-Ho 한국건설관리학회 2007 건설관리 : 한국건설관리학회 학회지 Vol.8 No.5
It is related to launch the CM market and to increase the profit and entire ability in company that is enforcing the ability of construction management in large-scaled construction company. According to the CM market in U.S, CM market is increased with competing to the companies, that is E&C, general contractor, design firm, specialized CM firm. Also domestic market is similar to US market. In this situation, large-scaled construction companies are filled with construction management ability for competing with foreign companies and domestic CM firms. This paper suggests how to enforce the construction management ability through education, and shows the detailed education strategy considered the fields, divisions and positions. 대형시공회사에 있어 CM 역량강화의 문제는 비단 CM 시장의 진출뿐만 아니라 회사의 역량 강화, 경쟁자와의 차별성 및 수익성의 증대라는 측면에서 대단히 중요한 의미를 갖는다. 현재 미국의 CM시장을 분석하여 본 결과 CM은 EC, GC, 그리고 설계 및 전문 CM사와의 각축속에서 그 규모가 점차 확대되고 있고, 국내의 경우의 경우도 그와 유사하게 진행되어가고 있다. 이러한 상황에 대형시공사는 국내시장에서 기존의 CM 강자들과의 경쟁과 해외시장에서 선진 외국사와의 경쟁을 위해서는 부족한 CM 역량에 대한 시급한 보완이 필요하다고 판단된다. 이에 본 논문은 CM 역량 강화를 위한 교육 전략 수립에 초점을 맞추어 연구를 진행하였고, 각 현장, 사업본부, 직급을 고려한 교육 전략을 제시하였다.
Message Complexity Analysis of MANET Address Autoconfiguration-Single Node Joining Case
김상철,Kim, Sang-Chul The Korean Institute of Communications and Informa 2007 韓國通信學會論文誌 Vol.32 No.5B
네트워크 계층의 MANET 라우팅 프로토콜이 개발될 때 가장 주요한 관심사는 라우팅 오버헤드 (Overhead)의 축소이다. 본 논문에서는 MANET 에서 단일 노드가 자동 네크워킹 프로토콜에 의해 IP 주소를 획득할 때의 라우팅 오버헤드 (메시지 복잡도)를 정량적으로 분석하는 수학적 방법을 제안한다. MANET에서 자동 네크워킹 프로토콜은 IP 주소 할당시 IP 주소 충돌회피에 사용된다. 메시지 복잡도는 Upper Bound에 의해 수학적으로 정량화 되고, 실제 주소 할당을 컴퓨터 시뮬레이터로 구현하여, 제안된 Upper Bound와 시뮬레이션 결과를 비교, 분석한다. 메시지 복잡도의 Upper Bound는 Worst Case 시나리오 분석에 의해 유도된다. This paper proposes a novel method to perform a quantitative analysis of message complexity and applies this method in comparing the message complexity among the mobile ad hoc network (MANET) address autoconfiguration protocols (AAPs). To obtain the upper bound of the message complexity of the protocols, the O-notation of a MANET group of N nodes has been applied. The message complexity of the single node joining case in Strong DAD, Weak DAD with proactive routing protocols (WDP), Weak DAD with on-demand routing protocols (WDO), and MANETconf has been derived as n(mO(N)+O(t)), n(O(N)+O(t)), n(O(N)+2O(t)), and nO((t+1)N)+O(N)+O(2) respectively. In order to verify the bounds, analytical simulations that quantify the message complexity of the address autoconfiguration process based on the different coflict probabilities are conducted.
김상철,김만원,Kim, Sang-Chul,Kim, Maan-Won 대한용접접합학회 2010 대한용접·접합학회지 Vol.28 No.1
In this paper crack propagation analyses in the dissimilar metal weldment of a nozzle were performed using a finite element alternating method (FEAM). A two-dimensional axisymmetric finite element nozzle model was prepared and welding simulation including the thermal heat transfer analysis and the thermal stress analysis was performed. Initial cracks were inserted at weld and heat affected zone in the finite element model which has welding residual stress distribution obtained from the welding simulation. To calculate crack propagation trajectories of these cracks, a new fatigue crack evaluation module was developed in addition to the previous FEAM program. With the new FEAM fatigue crack evaluation module, crack propagation trajectory and crack growth time were calculated automatically and effectively.
김상철,김만원,Kim, Sang-Chul,Kim, Man-Won 대한용접접합학회 2014 대한용접·접합학회지 Vol.32 No.1
Although the fatigue design curve of ASME Code has enough margin with respect to alternating stress and cycles, the welding residual stress(WRS) should be included in fatigue analysis. In this paper, WRS distribution in a nozzle with dissimilar metal weldment was obtained by finite element analysis and was added in fatigue analysis. The fatigue analysis was performed by following the ASME Code including thermal and stress analysis applying with postulated 30 transient conditions. The calculated results of a cumulative fatigue usage factors(CUF) were compared for the case of the models with or without WRS effects. The results showed that the CUF at weldment and heat affected zone was affected by the WRS.
김상철,이상호,Kim, Sang-Chul,Lee, Sang-Ho 한국농공학회 2005 한국농공학회논문집 Vol.47 No.3
This study was conducted by the tests of materials engineering and soil mechanics to see the strength characteristics of the ‘Cement-Mixed Soil'. To sum up my experiments, I would like to present the results which are the theoretical base and fundamental data to establish the standard design including the design of mixing proportions of the soil as a construction material. In conclusion, in this study the optimum cement mixing ratio is $9\%$ and in this ratio the optimum moisture content of compaction work is $19.3\%$ from the analysis of the strength characteristics, as well as in consideration of the economic profits and nature familiar facts.