비정상 3상소재의 유효전도율

김인찬,Kim, In-Chan 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.3

A problem of determining the effective conductivity of a useful model of sphere-matrix type, disordered three-phase composite media is considered. Specifically, a three-phase media in which two-phase composite spheres, consisting of spheres of conductivity $k_2$((phase 2) and concentric shells of conductivity $k_3$(phase 3), are randomly distributed in a matrix of conductivity $k_1$( (phase 1) is considered. As for the structure models configuring three-phase composite media, three different structure models of PCS, PS-1 and PS-2 models are defined, which are analogous to well-established PCS, PS structure models of two-phase composite media. Futhermore, a generalized PS-PCS structure model is proposed to incorporate thesee three different models in one. Effective condectivity $k^{\ast}$of multiphaes composite media is greatly influenced by the phase connectivity of each disspersed phase material, as well as phase conductivities and phase volume fractions. Phase connectivity of three-phase PCS, PS-1, PS-2 composite media is quantified by the impentrability parameter $\lambda$. Mathematically rigorous first-order cluster bounds on $k^{\ast}$ are derived for these models of three-phase composite media, and as computation examples, first-order cluster bounds on $k^{\ast}$ for three-phase composites consisting of largely different phase conductivities are computed and compared as function of concnectivity parpmeter $\lambda$. Results and discussions are given.

비정형 혼합재 이동성질의 변동

김인찬,Kim, In-Chan 대한기계학회 1996 大韓機械學會論文集B Vol.20 No.9

The notion of effective transport property of a heterogeneous medium implies that the medium is large enough that the ergodic theorem holds and local fluctuation of the property can be neglected. In case that the medium is not large enough compared to its characteristic microstructure length scale, the effective property fluctuates and differs from the value of the medium being large enough. As a representative transport phenomenon, diffusion was considered and the fluctuation of varying effective diffusion property, diffusion coarseness $C_k$, was defined as a quantifying parameter. Scaled effective diffusion property, <k$^*$>/k$_1$ and $C_k$ were computed for the two phase random media consisting of matrix of diffusion coefficient k$_1$ and spheres of diffusion coefficient k$_2$. Numerical simulations were performed by use of the so-called first passage time technique and data were collected for existing microstructure models of hard spheres(HS), overlapping spheres(OS) and penetrable concentric shells(PCS).

세계 강군의 다문화 적용사례 연구

김인찬,조상근,김종훈,홍명숙,방동협,박상혁,Kim, In Chan,Cho, Sang Keun,Kim, Jong Hoon,Hong, Myung Sook,Bang, Dong Hyup,Park, Sang Hyuk 국제문화기술진흥원 2022 The Journal of the Convergence on Culture Technolo Vol.8 No.6

The Republic of Korea Army predicted that the continuous decline in fertility rate and the low birth rate, one of the biggest issues in our society, would lead to a security crisis due to a lack of military personnel, and revised the Military Service Act in 2010 to prevent enlistment of 'clearly mixed races', which had previously restricted enlistment. made it compulsory As a result, 50 children from multicultural families enlisted in the military in 2011, and the Military Manpower Administration at the time predicted that more than 8,000 people would enlist every year after 2020. This poses another challenge for the Army. A lack of understanding and respect for different languages, religions, and eating habits can lead to conflict among members, which will lead to weakening of combat power. Therefore, through a case study of multicultural application by world powers, the history of success and failure of respect for multiculturalism and the current policy of respecting multiculturalism of the U.S. Army are studied to examine the direction of our army.

도전성 플라스틱의 전도 퍼콜레이션

김인찬,Kim, In Chan 대한기계학회 1999 大韓機械學會論文集B Vol.23 No.6

A composite plastic, where long metallic fibers are used as filling materials, is transformed from nonconducting to conducting medium as the volume fraction of filling metallic fibers is increased from zero : such drastic change in property is called the percolation. It is desired both for practical and theoretical purposes to understand the physics underlying the percolation and to estimate the percolation threshold that is defined by the minimum volume fraction of the metallic fibers for which the percolation occurs. In this study, percolation thresholds are calculated by Monte Carlo Computer simulation. Both lattice and continuum spaces are considered and detailed microstructures of metallic fibers are modelled as rigid and flexible bodies for both model spaces. Simulations are carried out for wide range of aspect ratios and discussions are given.

라비뇨방식 유성기어를 채택한 자동변속기의 변속과도특성 해석

김인찬,이승종,Kim, I.C,Yi, S.J 대한기계학회 1997 大韓機械學會論文集A Vol.21 No.11

In this paper, the analysis of the shift transient characteristics for the Ravigneaux type automatic transmission has been carried out using dynamic models of the automatic trnasmission. It is necessary to understand the overall system including multi-plate clutch, band brake, one way clutch, and planetary gears. The equations of motion are derived from the dynamic models of the automatic transmission. The GUI computer simulation program has been developed to analyze the shift transient characteristics of the vehicle equipped with the Ravigneaux type automatic transmission.

이류 유동장의 초확산과 무작위성

김인찬,Kim, In Chan 대한기계학회 1999 大韓機械學會論文集B Vol.23 No.9

Superdiffusive transport motions of passive scalars are numerically considered for various advection velocity fields. Calculated exponents ${\alpha}$ in the superdiffusion-defining relation ${\sigma}^2(t){\sim}t^{\alpha}$ for model flow fields agree to the theoretically predicted values. Simulation results show that the superdiffusion takes place as the tracers' motion become less random, compared to their motion at the pure molecular diffusion. Whether the flow field is random or not, degrees of superdiffusion are directly related to the velocity autocorrelation functions along the tracers Lagrangian trajectories that characterize degrees of randomness of the tracers' motion.

소용량 건물용 연료전지시스템 블로워의 가혹조건 평가에 관한 연구

김강수(Kangsoo Kim),이덕권(Deokkwon Lee),이정운(Jungwoon Lee),김은정(Eunjung Kim),김인찬(Inchan Kim),김영규(Younggyu Kim),신헌용(Hunyong Shin) 한국가스학회 2012 한국가스학회지 Vol.16 No.6

연료전지는 우수한 도시가스 인프라로 안정적인 에너지공급이 가능하고, 연료 다변화가 가능한 신에너지 기술이다. 연료전지 상용화를 위해 시스템의 성능 및 신뢰성뿐만 아니라, 가격의 저감이 필수적이다. 소용량 건물용 연료전지시스템에서 가격비중이 매우 높은 보조기기의 가격저감 연구의 일환으로, 국내 제작된 블로워의 안전 성능을 평가하고 개선방향을 모색하고자 하였다. 본 연구에서는 실제 연료전지시스템의 작동환경과 가장 유사한 환경에서 블로워의 성능 및 가혹조건 평가를 수행하였다. 블로워를 70℃ 온도조건에서 장기 가동 시 유량성능, 기밀성능 및 열적거동의 상관관계를 파악하여, 블로워의 성능 저하에 영향을 미치는 모터열화, 다이어프램 재질 및 토출구 구조 등의 주요인자를 도출하였다. The fuel cell is one of the renewable energy sources. And it is a new source of energy that can be applied to various fuels and continuously supported by the excellent city-gas infrastructure. It is important to improve performances and reliabilities, and reduce the cost of fuel cell systems for commercialization. And, some safety performances of blower domestically produced are evaluated and some improvements are researched to save the cost of fuel cell systems. In this paper, the performance and worst stress condition of blowers are evaluated in operating environment similar to the fuel cell systems. Actually, the correlation of flow, leakage and thermal behavior are evaluated in the worst stress condition at 70℃ and, some major factors of blower degradation such as a motor deterioration, material and structures of the outlet are examined.

소용량 건물용 연료전지시스템 블로워의 가혹조건 시험평가

김강수(Kangsoo Kim),이덕권(Deokkwon Lee),이정운(Jungwoon Lee),김은정(Eunjung Kim),김영규(Younggyu Kim),김인찬(Inchan Kim),신헌용(Hunyong Shin) 한국가스학회 2012 한국가스학회 학술대회논문집 Vol.2012 No.11

동력전달시스템 기초설계용 software 개발에 관한 연구

김인찬(I.C.Kim),서진원(J.W.Suh),최천(C.Choi),이승종(S.J.Yi) 한국자동차공학회 1995 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1995 No.11_1

In this study, the performance analysis of the vehicle with the Ravigneaux type automatic transmission has been carried out using information of engine and drivetrain. It is necessary to understand the overall<br/> system including engine, torque converter, clutch, planetary gears, and road load. The equations of motion are derived from the dynamic model. An integrated computer simulation program has been developed to analyze the powertrain performance of the vehicle with the Ravigneaux type automatic transmission.<br/>

응급의료센터에서 아세트아미노펜 과다복용 환자의 검사실 분석 현황: 일개 중독분석실 농도 분석자료 포함

김인찬 ( In Chan Kim ),원신애 ( Sinae Won ),이아름 ( Arum Lee ),정하은 ( Haeun Jung ),이정선 ( Jeongsun Lee ),오범진 ( Bum Jin Oh ) 대한임상독성학회 2021 대한임상독성학회지 Vol.19 No.1

Purpose: Acetaminophen (APAP) is a widely available drug responsible for a large part of drug-induced hepatotoxicity in developed countries. Although acetaminophen overdose cases in Korea are being continuously reported, there are no reports related to the level of this drug in the patient’s blood or of laboratory analysis at emergency departments (ED). This study sought to analyze the acetaminophen overdose cases at a toxicological laboratory and to survey APAP analysis services offered at select EDs. Methods: We analyzed the demographic and analytic data at a toxicological laboratory run by the National Emergency Medical Center (NMC) in 2019-2020. We surveyed the APAP laboratory service in the 38 regional emergency medical centers (EMCs) and 68 local EMCs near the toxicological laboratory. Results: We studied 175 acute poisoning cases (112 women) with positive blood APAP results (mean age 47.0±24.1 years). Suicide attempts comprised 40.0% of the cases and 30.3% APAP overdose events. In the univariate analysis, we observed that patients were significantly younger, with fewer underlying medical diseases. There were a higher number of APAP overdose events, more favorable initial mental status, more toxic quantity intake in the above treatment line group (p<0.05), In multivariate analysis, the toxic amount intake was significantly more frequent in the above treatment line group (p<0.01). Hospital APAP analysis services were available in six EMCs (3/38 regional and 3/68 local). The hospital blood APAP level reporting intervals were shorter than outside-hospital laboratory services (p<0.01, regional 7.0±3.0 vs. 40.6±27.5, local 5.3±3.1 vs. 57.9±45.1 hours). The NMC toxicological laboratory reporting interval was shorter than the other outside-hospital laboratories (p<0.01, regional 5.7±0.6 vs. 50.2±22.7 local 7.5±3.0 vs. 70.5±41.5 hours). Conclusion: Over the treatment line group, toxic amount intake was significantly more frequent. Only six of 106 EMCs have their own APAP analysis service in their hospitals.