• Molecules and Cells
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• 제43권8호
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• pp.749-762
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• 2020

The migration, dedifferentiation, and proliferation of vascular smooth muscle cells (VSMCs) are responsible for intimal hyperplasia, but the mechanism of this process has not been elucidated. WD repeat domain 1 (WDR1) promotes actin-depolymerizing factor (ADF)/cofilin-mediated depolymerization of actin filaments (F-actin). The role of WDR1 in neointima formation and progression is still unknown. A model of intimal thickening was constructed by ligating the left common carotid artery in Wdr1 deletion mice, and H&E staining showed that Wdr1 deficiency significantly inhibits neointima formation. We also report that STAT3 promotes the proliferation and migration of VSMCs by directly promoting WDR1 transcription. Mechanistically, we clarified that WDR1 promotes the proliferation and migration of VSMCs and neointima formation is regulated by the activation of the JAK2/STAT3/WDR1 axis.

• Asian-Australasian Journal of Animal Sciences
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• 제26권8호
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• pp.1119-1126
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• 2013

The objective of this study was to compare the goodness of fit of four lactation curve models: Wood's Gamma model (WD), Wilmink (WL), and Pollott's multiplicative two (POL2) and three parameters (POL3) and to determine the environmental factors affecting the complete lactation curve of F1 dairy sheep under organic management. A total of 5,382 weekly milk yields records from 150 ewes, under organic management were used. Residual mean square (RMS), determination coefficients ($R^2$), and correlation (r) analysis were used as an indicator of goodness of fit for each model. WL model best fitted the lactation curves as indicated by the lower RMS values (0.019), followed by WD (0.023), POL2 (0.025) and POL3 (0.029). The four models provided total milk yield (TMY) estimations that were highly correlated (0.93 to 0.97) with observed TMY (89.9 kg). The four models under estimated peak yield (PY), whereas POL2 and POL3 gave nearer peak time lactation estimations. Ewes lambing in autumn had higher TMY and showed a typical curve shape. Higher TMY were recorded in second and third lambing. Season of lambing, number of lambing and type of lambing had a great influenced over TMY shaping the complete lactation curve of F1 dairy sheep. In general terms WL model showed the best fit to the F1 dairy sheep lactation curve under organic management.

• Journal of Biosystems Engineering
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• 제37권3호
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• pp.131-139
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• 2012

In this study, we developed a simulation program for the prediction of tractive performance of a tractor, by applying a widely used empirical model for tractive performance prediction of single tire, Brixius. The tractive performance prediction program can readily predict and estimate tractive performance according to various soil conditions and different specifications of tractors. The program was developed with the considerations of tractor's specification-related parameters (e.g., weight, tire size, and wheelbase of the tractor), a soil parameter (i.e., cone index which represents the soil strength), and operating conditions of the tractor (e.g., theoretical speed and driving types such as 2WD and 4WD). Also, the program was designed to provide tractive performance prediction results of tractors such as gross traction, motion resistance, net traction, and tractive efficiency, in the form of not only numerical values but also graphical visualization. To evaluate the feasibility of the program, we input three different soil conditions (which have different cone indexes each other) and tractor operating conditions to the program and analyzed the tractive performance from each input condition. From the analysis, it can be concluded that the developed program can be effectively utilized to predict the tractive performance under various soil conditions and driving types of tractors with different specifications.

• Journal of Astronomy and Space Sciences
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• 제16권2호
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• pp.209-216
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• 1999

근접촉쌍성으로 분류된 두 개의 식쌍성 DO Cas와 SW Lyn의 광도곡선을 분석하여 이들의 로쉬모형을 알아보았다. DO Cas는 이 연구를 위하여 새로이 관측하였으며 SW Lyn은 이미 발표되어 있는 자료를 이용하였다. DO Cas에 대한 관측은 짧은 기간에 완성하여 체계적인 관측 오차를 최소화하였다. WD 모델을 사용한 우리의 분석에 의하면, DO Cas는 근접촉쌍성으로 분류될 수 있으나 SW Lyn은 준분리형으로 분류하는 것이 타당함을 알 수 있었다. 더구나, DO Cas는 접촉쌍성으로도 분류가 가능하므로 근접촉쌍성이 하나의 독립된 로쉬모형으로 인정되기 위해서는 근접촉쌍성으로 분류된 쌍성들의 광도 곡선을 보다 면밀하게 재분석할 필요가 있다고 판단된다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 추계학술발표회
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• pp.253-258
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• 2006

본 연구는 우리나라 RCC/RSC의 효율성을 2개의 입력변수와 5개의 출력변수를 자료를 토대로 퍼지 DEA를 이용하여 측정 평가하였다. 특히, 본 연구에서는 해양사고 발생자료 뿐만 아니라 환경스트레스치에 의한 잠재적 해양사고 발생가능 자료도 고려하여 운영효율성을 분석하였다. 한편, 현실자료에는 수많은 애매성이 존재하기 때문에 본 연구에서는 DEA법에 퍼지이론을 이용한 퍼지 DEA 법을 이용하였다. 이 퍼지 DEA법은 ${\alpha}-cut$ 을 기반으로 한 크리습 선형계획문제로 변환된 것으로 입/출력 변수를 삼각형 퍼지수로 하여 해를 산출하는 방법을 제안하였고, 제안된 퍼지 DEA를 이용하여 퍼지 RCC/RSC의 순위를 결정하였다. ${\alpha}-cut$를 0.5 로 하여 효율성을 산출한 결과 YS, BS, MP, TS, JJ, PH, US, IC, SC, DH, GS, TA, WD RCC/RSC 순으로 효율성 이 높게 나타났다. 따라서 효율성이 비교적 낮게 평가된TA, WD RCC/RSC는 효율성이 높은 준거집단을 참조하여 벤치마킹을 해야할 필요가 있다.

• 해양환경안전학회지
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• 제13권3호
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• pp.207-212
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• 2007

본 연구는 우리나라 RCC/RSC의 효율성을 2개의 입력변수와 5개의 출력변수로 한 토대로 퍼지 DEA를 이용하여 측정 평가하였다. 특히, 본 연구에서는 해양사고 발생자료 뿐만 아니라 환경스트레스치에 의한 잠재적 해양사고 발생가능 자료도 고려하여 운영효율성을 분석하였다. 한편, 현실자료에는 수많은 애매성이 존재하기 때문에 본 연구에서는 DEA법에 퍼지이론을 이용한 퍼지 DEA법을 이용하였다. 이 퍼지DEA법은 ${\alpha}$-cut을 기반으로 한 크리습 선형계획문제로 변환된 것으로 입/출력 변수를 삼각형 퍼지수로 하여 해를 산출하는 방법을 제안하였고, 제안된 퍼지 DEA를 이용하여 퍼지 RCC/RSC의 순위를 결정하였다. ${\alpha}$-cut을 0.5로 하여 효율성을 산출한 결과 YS, BS, MP, TY, JJ, PH, US, IC, SC, DH, GS, TA, WD RCC/RSC 순으로 효율성이 높게 나타났다. 따라서 효율성이 비교적 낮게 평가된 TA, WD RCC/RSC는 효율성이 높은 준거집단을 참조하여 벤치마킹을 해야 할 필요가 있다.

• 방송과미디어
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• 제15권4호
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• pp.55-65
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• 2010

HEVC 표준화가 JCT-VC에서 진행되고 있으며, 2010년 4월 1차 회의와 2010년 7월 2차 회의를 거쳐, 2010년 10월 제3차 회의에서 WD(Working Draft)인 HM (HEVC Test Model)이 결정되었다. 본 고에서는 HM에 채택된 움직임 정보 부호화 관련 기술과 화면간 예측보간기술에 대해 설명한다.

• East Asian mathematical journal
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• 제37권1호
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• pp.141-147
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• 2021

In [1], we studied the PDE system with time-varing delay. Time delay occurs due to loosening in a high-speed moving axially directed membrane (string, belt, or plate) at production. Our purpose in this work derives a mathematical model with internal time delay. First, we consider the physical phenomenon of axially moving membrane with respect to kinetic energy, potential energy and work done. By the energy conservation law in physics, we get the second order nonlinear PDE system with internal time delay.

• 한국CDE학회논문집
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• 제3권1호
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• pp.40-47
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• 1998

Recently, the various driving simulator have been used widely to analyze the handling performance of vehicle and to verify the motion control algorithm of vehicle. In this study, a virtual driving simulator based on the 20-DOF vehicle model is realized to estimate the handling performance and stability of a 4WS (Four-wheel-steering) and/or 4n(Four-wheel-driving) vehicle. Especially the DC motor controlled 4WS actuator is modelled in order to reflect the effect of the responsiveness of actuator on the handling performance and stability. And the realized simulator can be applied to develope a real time simulation system for designing and testing the real vehicles.

• 한국자동차공학회논문집
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• 제6권2호
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• pp.21-31
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• 1998

In this paper, a thermo-mechanical model for viscous coupling(VC) was suggested and torque equation in viscous mode was derived considering the effects of geometry of the plates, thermo-mechanical dynamics, silicon oil characteristics and dissolved air characteristics in the silicon oil. Theoretical results were in good accordance with experimental results demonstrating that VC thermo-mechanical model and the theoretical equations, response of the torque transmitted, pressure, temperature and time to the hump were investigated. Simulation results showed that filling rate of the silicon oil plays an integral role not only in the steady state torque characteristics but also in determining the time to hump.