• 대한수학회논문집
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• 제21권3호
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• pp.475-490
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• 2006

We give a way to obtain formulas for ${\pi}*{\psi}^{\kappa}_{n+1}$ in terms ${\psi}$ and ${\lambda}-classes$ where ${\pi}=\bar M_{g,n+1}{\rightarrow}\bar M_{g,n}(g=0,\;1,\;2)$ by the localization theorem. By using the formulas, we obtain Kontsevich-Manin type reconstruction theorems for $\bar M_{0,\;n}(\mathbb{R^m}),\;\bar M_{1,\;n},\;and\;\bar M_{2,\;n}$. We also (re)produce a lot of well-known relations in tautological rings, such as WDVV equation, the Mumford relations, the string and dilaton equations (g = 0, 1, 2) etc. and new formulas for ${\pi}*({\lambda}_g{\psi}^{\kappa}_{n+1}+...+{\psi}^{g+{\kappa}_{n+1}$.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.506-509
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• 2004

This paper proposes Headed bar as reinforcement of beam-column joint, and proves seismic performance and reduction of reinforcement congestion. In these case, the use of Headed bars have obvious advantages. The greatest benefit of using Headed bars is not only improved structural performance of beam-column joints, but also the ease of fabrication, construction, and placement. Three-dimensional finite element analysis model is compared with test program which was fulfilled by the proposed model with Headed bar. Also, the plastic hinge region is relocated to the center of the longitudinal beam length according to the strong column-weak beam design philosophy, so Headed bar is used as the joint reinforcement. Therefore, this paper presents results of a computer analysis of a practical solution for relocating potential beam plastic hinge regions by the placing of straight - Headed bar.

• Journal of the Optical Society of Korea
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• 제15권3호
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• pp.272-277
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• 2011

The effect of the M-window color mixing bar on the characteristics of color mixing and hot spots in the edge-lit backlight employing red (R), green (G), blue (G) light emitting diodes (LED) were studied in terms of the structure of the M-window color mixing bar. The rays from RGB LEDs entering the M-window bar were mixed by internal reflection and scattering inside the M-window bar so that the hot spots and color separation were minimized. The M-window bar was designed and fabricated and the simulation results are matched quite well to experimental data.

• 대한기계학회논문집A
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• 제37권4호
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• pp.447-459
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• 2013

실제 산업현장에서 비젼 시스템을 적용하기에는 로봇 비젼 제어알고리즘의 기구학모델의 정확도, 로봇이 움직이는 동안 카메라 초점거리와 방위에 대한 보정, 3 차원 물리적 좌표에서 2 차원 카메라 좌표로의 매핑에 대한 이해 등 해결해야 할 많은 문제점들이 있다. 본 논문에 제안된 비젼 시스템 모델은 카메라와 로봇 사이의 상대적인 위치가 알려지지 않아도 제어가 가능하고, 카메라 보정 문제를 해결하기 위해 6 개의 카메라 매개변수를 가지는 비젼 시스템 모델을 제시하였으며, 이를 이용하여 로봇 비젼 제어알고리즘 개발에 N-R 방법과 EKF 방법을 적용하였다. 최종적으로 N-R 과 EKF 방법에 의하여 개발된 로봇 비젼 제어 알고리즘의 위치 정밀도와 데이터 처리 시간을 얇은 막대 배치작업을 수행하여 비교하였다.

• 대한수학회보
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• 제21권2호
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• pp.99-106
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• 1984

J. Yeh has recently introduced the concept of conditional Wiener integrals which are meant specifically the conditional expectation E$^{w}$ (Z vertical bar X) of a real or complex valued Wiener integrable functional Z conditioned by the Wiener measurable functional X on the Wiener measure space (A precise definition of the conditional Wiener integral and a brief discussion of the Wiener measure space are given in Section 2). In [3] and [4] he derived some inversion formulae for conditional Wiener integrals and evaluated some conditional Wiener integrals E$^{w}$ (Z vertical bar X) conditioned by X(x)=x(t) for a fixed t>0 and x in Wiener space. Thus E$^{w}$ (Z vertical bar X) is a real or complex valued function on R$^{1}$. In this paper we shall be concerned with the random vector X given by X(x) = (x(s$_{1}$),..,x(s$_{n}$ )) for every x in Wiener space where 0=s$_{0}$ $_{1}$<..$_{n}$ =t. In Section 3 we will evaluate some conditional Wiener integrals E$^{w}$ (Z vertical bar X) which are real or complex valued functions on the n-dimensional Euclidean space R$^{n}$ . Thus we extend Yeh's results [4] for the random variable X given by X(x)=x(t) to the random vector X given by X(x)=(x(s$_{1}$).., x(s$_{n}$ )).

• 한국자동차공학회논문집
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• 제3권6호
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• pp.55-68
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• 1995

Approximately 30 to 70 % of the mechanical losses in a reciprocating engine are contributed by the friction at the piston ring-cylinder interface. The friction characteristics of the piston ring during engine operation is known to as mixed lubrication experimentally. The mixed lubrication models based on the Average Reynolds Equation have been used by this time in order to study the tribological performance of the ring. However, the Average Reynolds Equation contains the expected value term(${\bar{h}}_r$) of local film thickness as well as nominal film thickness(h), so that the work of numerically solving ${\bar{h}}_r$ must be included to obtain the pressure in the oil film. The process of solving ${\bar{h}}_T$ causes a greater multiplying in the numerical solution. In this paper the mixed lubrication analysis using the Simplified Average Reynolds Equation in the piston ring is presented. This equation has only h as oil film thickness term. Therefore the tedious numerical procedure required to obtain ${\bar{h}}_T$ is not needed, and also, computation time can be reduced.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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• pp.242-245
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• 2003

A garter spring, which is a long, special, close-coiled extension spring with its ends joined to form a ring, is used in tulip contactor between vacuum circuit breaker and bus bar in switchgear. To carry short-time current and resist welding at the contact surface in the tulip contactor, the garter spring must transmits an uniform contact force to the contact surface through the contact chips arranged in the circumference of bus bar. In this paper, the system for measurement of the contact force by the garter spring is developed. Using the developed measurement system, the design of the connection structure including the garter spring is reviewed to obtain the uniform contact forces in all of contact chips.

• 충청수학회지
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• 제30권1호
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• pp.129-139
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• 2017

For a map $p:X{\rightarrow}A$, there are concepts of co-$H^p$-spaces, co-$T^p$-spaces, which are generalized ones of co-H-spaces [17,18]. For a principal cofibration $i_r:X{\rightarrow}C_r$ induced by $r:X^{\prime}{\rightarrow}X$ from $\imath:X^{\prime}{\rightarrow}cX^{\prime}$, we obtain some sufficient conditions to having extensions co-$H^{\bar{p}}$-structures and co-$T^{\bar{p}}$-structures on $C_r$ of co-$H^p$-spaces and co-$T^p$-structures on X respectively. We can also obtain some results about co-$H^p$-spaces and co-$T^p$-spaces in homology decompositions for spaces, which are generalizations of Golasinski and Klein's result about co-H-spaces.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.60-65
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• 2005

Nowadays HCFCs refrigerant are restricted because it cause depletion of ozone layer. However, natural gases such as ammonia as an organic compound, propane and propylene as hydrocarbon are easy and cheap to obtain as well as environmental. Accordingly, this experiment apply the $NH_3$ and R22 to study the performance characteristic from the superheat control and compare the energy efficiency of two refrigerants from the high performance. The condensing pressure of refrigeration system is increased from 15bar to 16bar and degree of superheat is increased from 0 to $10^{\circ}C$ at each condensing pressure. As the result of experiment, when comparing the each COP, we knew the $NH_3$ is suitable as the alternative refrigerant of the R22.

• Food Science and Biotechnology
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• 제15권3호
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• pp.339-340
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• 2006

The pattern of drug resistance and incidence of R-factors were studied in Shigella sonnei as food-borne pathogen strains isolated from chicken meat in Iran. In this study we examined for transferring R-factors of S. sonnei to sensitive Escherichia coli $k_{12}{\bar{F}}(\lambda)$. The results showed that 19 out of 57 strains (33.3%) were resistant to one or more drugs and multiple drug resistance was more common than single drug resistance. The most predominant pattern of resistance observed was Tetracycline (Tc), Chloramphenicol (Cm), Streptomycin (Sm), and Sulfonamide (Su). 100% of the strains from the Caspian littoral transferred at least a part of their resistance pattern to sensitive E.coli $k_{12}{\bar{F}}(\lambda)$.