• 한국발생생물학회지:발생과생식
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• 제23권2호
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• pp.171-181
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• 2019

To produce healthy and stable seed production, we need to obtain information and understand vision that affects behavior of red spotted grouper. We examined their expression and retinal development during the juvenile development. Short-wavelength sensitive opsin (SWS2), a cone photoreceptor, began to be expressed from lens and ear vesicle formation stage and its expression increased until 10 days after hatching (dah). In case of middle-wavelength sensitive opsin (MWS), its expression was detected at 3 dah and reached the highest level at 21 dah. The expression of long-wavelength sensitive opsin (LWS) was first observed from 3 dah and their expression decreased thereafter. Rhodopsin, a rod photoreceptor, was found to be expressed from 2 dah and its expression reached the highest level at 50 dah. The outer nuclear layer (ONL), inner nuclear layer (INL) and ganglion cell layer began to differentiate at 2 dah, while choroid first appeared at 4 dah so that the eyes became black. These results indicate that the development of retina mostly completes around 4 dah. It seems that the development of the retina and the expression of the opsin genes are closely related to the behavior such as hunting prey, considering that the timing of the completion of the development of the retina, the timing of gene expression, and the timing of completion of yolk absorption are similar.

• Toxicological Research
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• 제16권1호
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• pp.53-57
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• 2000

A mutagenicity testing system using a specific locus mutation of Bombyx mori was introduced from National Institute of Genetics in Japan. In the system, mutagenicity could be detected by the egg color manifested by the pe and/or re genes, which is a kind of recessive visible mutation of the insect. The efficiency to detect mutagenicity of the system was examined and improved. To promote the sensitivity of the system to mutagens, eight varieties of Bombyx mori were tested for their sensitivity to two mutagens, EMS and MMC. Two varieties of the silkworm, N12 and C5, were finally selected as the most sensitive ones. The most sensitive development stage of the silkworm to mutagens was mid and late pupal stages for female and male, respectively. The system will be applied to test unknown mutagens after some more detail examination about its sensitivity.

• 응용통계연구
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• 제8권1호
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• pp.27-38
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• 1995

본 논문에서는 사회적으로나 개인적으로 매우 민감한 조사에서 모집단이 양적속성을 갖는 여러 개의 층으로 구성되어 있을 때, 층의 크기를 모르는 경우 층화표본을 위하여 이중추출법을 이용하는 층화이중추출법에 의한 양적속성의 무관질문모형을 제안하였다. 그리고, 층화이중추출에 있어서 각 층의 표본배분에 관해 비례배분, 최적배분으로 나누어 각 층의 크기를 알고 있는 경우에 층화추출법에 의한 양적속성의 무관 질문모형과 그 효율성을 비교하였다.

• Computers and Concrete
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• 제12권1호
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• pp.79-90
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• 2013

In this study, dynamic characteristics such as natural frequencies, mode shapes and damping ratios of RC frame is determined for different construction stages using Operational Modal Analyses method under ambient vibration. Full scaled, one bay and one story RC frames are selected as an application for different construction stages such as plane, brick in-filled and brick in-filled with plaster. The RC frame is vibrated by natural excitations with small impact effects and the response signals are measured using sensitive accelerometers during ambient vibration tests. Measurement time-frequency span and effective mode number are determined by considering similar studies in literature. Sensitive seismic accelerometers are used to collect signals obtained from the experimental tests. To obtain experimental dynamic characteristics, output-only system identification technique is employed namely; Enhanced Frequency Domain Decomposition technique in the frequency domain. It is demonstrated that the ambient vibration measurements are enough to identify the most significant modes of RC frames.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 2002년도 춘계학술대회 및 총회
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• pp.32-36
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• 2002

Lymphoma is a group of neoplastic disease of lymphoid tissues, which can be classified into categories of Hodgkin's disease and non-Hodgkin's lymphoma(NHL). Prognosis of lymphoma depends on the extent of disease(staging) especially in Hodgkin's disease, but also depends on the histologic make up in non-Hodgkin's lymphoma. Although non-Hodgkin's lymphoma is a neoplastic transformation of lymphoid cell it is a collection of disease with merphologically and immunologically diverse make up. Consequently the classification of NHL has changed frequently and evolved according to the progress of immunologic and molecular knowledge added to the original morphologic classification. Lymphoma is a disorder sensitive to chemotherapy which often leads to cure of the disease even in advanced stage, while many other patients die from the progression of disease. Therefore, better understanding in newer classification and sensitive imaging technique, such as PET, in lymphoma will likely lead to the improvement of survival rate.

• 한국정밀공학회지
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• 제29권8호
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• pp.906-912
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• 2012

This paper presents the new method for a six-degree-of-freedom (DOF) motion measurement and those dynamic characterizations in an ultraprecision linear stage using angle sensor-implemented grating interferometry. It consists of a diffractive optical element, a corner cube, four separate two-dimensional position sensitive detectors, four photodiodes and auxiliary optics components. From the previous study, it was confirmed that the proposed optical system could measure a six-DOF motion error in a linear stage. In this article, six-DOF motion dynamic characteristics of the stage were investigated through the step response and with respect to the conditions with a different speed of a slide table. As a result, the natural frequency and damping ratio according to a six-DOF direction was obtained. Also, it was seen that the speed of slide table had an significant effect on a six-DOF displacement motion, especially, X, which was considered as the effect of friction mechanism and local elastic mechanical deformation in a slide guide.

• Journal of Electrical Engineering and Technology
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• 제10권6호
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• pp.2240-2248
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• 2015

The integration of the large-scale wind power brings great challenge to the stability of the power grid. This paper investigates and studies the fault on May 14, 2012 of the large-scale cascading trip-off of wind turbines in North China. According to the characteristics of the voltage variation, the fault process is divided into three stages: the pre-event stage, the critical stage before cascading, and the cascading stage. The scenes in the fault are reproduced, using the full-size actual power system model. Simulation models of double-fed induction generators (DFIGs) and SVCs including protection settings and controller strategies are carefully chosen to find out the reason of voltage instability in each stage. Some voltage dynamic that have never been observed before in the faults of the same kind are analyzed in detail, and an equivalent voltage sensitive dynamic model of DFIG is proposed for the fast computation. The conclusions about the voltage dynamics are validated by the actual PMU observation evidence.

• 유통과학연구
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• 제16권7호
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• pp.35-45
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• 2018

Purpose - The study investigates the impact of consignment on the economic performance in the supply chain with three stages. Through the analysis on distinct forms of consignment application, this study intends to answer to the question of how the consignment should be used in the multi-stage supply chain. Research design, data, and methodology - The proposed mathematical model represents the supply chain system with a manufacturer, a wholesaler, and a retailer. Three different forms of consignment application are considered depending on which stages adapt the consignment, and their system profits are compared with the traditional non-consignment system in numerical examples. Results - The numerical examples show that the serial consignment application performs better than any other forms of consignment as well as the non-consignment system. The additional analysis indicates that the system profit is significantly sensitive to the consignment rate. Conclusions - The outcome of this study implies the potential of consignment to improve the system performance even in the multi-stage supply chain system. Meanwhile, each supply chain member's preference to the specific form of consignment application could be different depending on which stage he has. All the supply chain members should jointly determine the appropriate consignment rates to obtain the best system performance.

• 디자인학연구
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• 제16권2호
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• pp.355-364
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• 2003

본 연구는 디자인의 프로세스를 2단계모델과 3단계모델로 구분하고 이들 각 모델의 효율성에 대하여 검증하였다. 2단계모델은 디자이너의 창의적인 마인드를 바탕으로 주관적이고 감각적으로 수행하는 디자인활동을 의미하며 반대로 3단계모델인 경우 객관적이고 논리적인 소비자 중심적자인 활동을 의미한다. 기존 연구에서는 이러한 두 가지 모델에 대하여 상대적으로 어떤 모델이 더 효과적인가에 대하여 의견의 일치를 이루어내지 못하였다. 본 연구에서는 이들 두 모델에 대하여 시장선도전략(market leader strategy)과 시장탐색전략(market seeker strategy)의 개념을 통해 각각의 효율성을 제시하였다 즉, 실증분석을 통해 명성브랜드라면 2단계모델을 바탕으로 한 시장선도전략이 그리고 비명성브랜드인 경우에는 3단계 모델을 바탕으로 한 시장탐색전략이 더 효율적이라는 상황적 입장을 제시하였으며 다만 어떤 상황에서 어떤 모델이 더 효율적인지에 대한 다각적인 검토가 더 필요하다고 제안하고 있다.

• 한국정밀공학회지
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• 제22권5호
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• pp.103-112
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• 2005

This paper presents one-axis high precision scanning system and illustrates the design of modified $X-Y-{\theta}$ stage as a tracker using VCM and commercialized air bearings for it. The scanning system for 100nm resolution is composed of the 3-axis stage and one axis long stroke linear motor stage as a follower. In this study a previous proposed and presented structure of VCM for the fine stage is modified. The tracker has 3 DOF($X-Y-{\theta}$ motions by four VCM actuators which are located on the same plane. So 4 actuating forces are suggested and designed to create least pitch and roll motions. This article will show about the design especially about optimal design. The design focus of this fine stage is to have high acceleration to accomplish high throughput. The optimal design of maximizing acceleration is performed in restrained size. The most sensitive constraint of this optimal design is heat dissipation of coil. There are 5 design variables. Because the relationship between design variables and system parameters are quite complicated, it is very difficult to set design variables manually. Due to it, computer based optimal design procedure using MATLAB is used. Then, this paper also describes the procedures of selecting design variables for the optimal design and a mathematical formulation of the optimization problem. Based on the solution of the optimization problem, the final design of the stage is also presented. The results can be verified by MAXWELL. The designed stage has the acceleration of about 5 $m/s^{2}$ with 40kg total mass including wafer chuck and interferometer mirror. And the temperature of coil is increased $50^{\circ}C$. In addition, the tracker is controlled by high precision controller system with HP interferometer for it and linear scaler for the follower. At that time, the scanning system has high precision resolution about 5nm and scanning resolution about 40nm in 25mm/s constant speed