• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권4호
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• pp.224-230
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• 2006

The conventional way to implement a bidirectional converter with boost/buck has been to use two general purpose PWM ICs with a single supply voltage. In this case, when one direction mode is in operation, the other is disabled and the output of the error amplifier of the disabled IC may be saturated to a maximum value or zero. Therefore, during mode transition, a circuit which can disable the switching operation for a certain time interval is required making it impossible to get a seamless transition. In this paper, the limitations of the conventional 42V/14V bi-directional DC/DC converter implemented with general current mode PWM ICs with a single supply voltage are reviewed and a new current mode PWM controller circuit with a dual voltage system is proposed. The validity of the proposed circuit is investigated through simulation. and experiments.

• 한국전기전자재료학회논문지
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• 제15권8호
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• pp.720-725
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• 2002

The fringe-field switching (FFS) mode was known to exhibit both a wide viewing angle and high transmittance, especially when using the liquid crystal (LC) with negative dielectric anisotropy. In the device, the LC director rotates almost in-plane. However, in the bright state the device shows bluish and yellowish color along parallel and perpendicular to the LC director at off-normal directions since the LC director rotates only in one direction. Such a problem was greatly improved using a wedge shape of only pixel electrodes. In this way two different field directions exist in a pixel, enabling the LC director to rotate in two opposite directions. Consequently, owing to dual domain effect when using the LC with negative dielectric anisotropy, the viewing angle characteristics are greatly improved.

• 한국응급구조학회지
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• 제9권2호
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• pp.101-110
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• 2005

In Korea, EMS Fund Operation seems to move the opposite direction to right way. The most initial EMS fund was consumed loan for some emergency patients without any particular results. Since 2002, the use of EMS fund also has shown a tendency to shift one side. By the results, it was 44.3% to support emergency medical centers, so called hospital EMS system and 28.4% to purchase ambulances and helicopters, and 1.6% to operate Central Medical Center, prehospital base in the EMS fund consumed in 2004. It was never supported for the environmental improvement and development of universities, colleges, and private EMS units having the primary responsibilities. The initial EMS fund using should be used for prehospital base, e.g., prehospital staffs, communications, and facilities and balanced development between public and private EMS units than any other fund using.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제13권1호
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• pp.17-26
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• 2007

Recently, the importance of the living environment for elderly people and its network is increasing. At the same time, the small-scale and multi-functional apartment house in which they can live is continuously required in Japan. For these reasons, it is appearing a new type of housing, Group-Living, where one lives together with others. It represents a way of communal living which is based on service at home. There are various problems such as felicity of each space, connections between the different areas, insufficiency of positioning on the aged welfare. Hence this research targets are grasp the present condition of Group-Living, to inquire the Space composition and types of it in Tokyo Area, and to suggest the direction of improvement of the small-scale and multi-functional apartment house for the aged.

• 한국경영과학회지
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• 제17권1호
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• pp.85-106
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• 1992

Much attention currently is being aimed to OA (office automation). OA has a potential for improving management decision making as well as increasing productivity of secretarial and clerical workers. This study construct a model that may be useful to the OA manager, in channeling OA efforts in the right direction. The purpose of this study is to analyze the improtance of critical success strategy for OA implementation, to test 5 hypotheses and 11 subsidiary hypothese of organizational characteristics and OA propulsion characteristics, and to suggest and evaluate a cussess strategy for OA implementation. The population consists of the Korean business in Seoul, 292 response of the 1000 questionaires were available and analyzed. The analytical methods are adopted on the frequency analysis to analyze the general characteristics, the one-way ANOVA, the Pearson's correlation analysis, the regression analysis for the test of the hypotheses.

• 대한한의학원전학회지
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• 제17권4호
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• pp.37-56
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• 2004

In the Circular flow of Meridians(經脈), the circulation of Nutrient Gi(營氣) is that the essence Gi(精氣) of food starts from Middle Cho(中焦), via heart and lung into the ring-type round of 12 Meridians(十二經脈) in turn of hand Meridians(水經) and foot Meridians(足經), Yang Meridians(陽經) and Eum Meridians(陰經). The circulation of Defensive Gi(衛氣) is that if going out from Eum part(陰分) into Yang part(陽分), is rounding on the Yang Meridians, if going out from Yang part into Eum part, is rounding on the five Jang(五臟) in order of Kidney(腎)-Heart(心)-Lung(肺)-Liver(肝)-Spleen(脾). Because the process of accumulating the essence Gi has a property of One-way flow, it flows from terminal to the direction of body trunk, has no distinct channel with its immaterial nature. and is concentrated on the lower part to that the five Jang belong.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 춘계학술대회 논문집
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• pp.97-99
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• 2013

We introduced an earthquake-resistant design using acoustic rnetamaterials. There are two way in that field: one is a cloaking method and the other is a shadow zone method of seismic waves. Cloaking is a general property of a wave that changes the direction depending on the refractive index. Metamaterials control the propagation and transmission of specified parts of the wave and demonstrate the potential to render an object seemingly invisible. The shadow zone is a method of negative modulus using many huge resonators and it attenuates the amplitude of the wave exponentially. We compared and explained the fimdarnental principles of the two methods.

• East Asian mathematical journal
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• 제31권2호
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• pp.189-210
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• 2015

Character means a person's nature and the mind and behavior to lead a desirable life personally and socially. Also character can be changed with education and environment. Therefore character education will be possible to do practice through various educational activities and life experiences in school. In other words, we think that students will get person's character required to lead a desirable life personally and socially beyond what they just learn knowledge and skill, enter the higher schools and succeed one's way. This study accepts merits of existing character education policy through subject(mathematics) education and focus on direction for character education through subject(mathematics) education for systematic and synthetic approach for practice of character education. For this, we will see applicability of the plan for character education in the whole subject education, in particular focusing on cases of character education in mathematics subject.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 봄 학술발표회 논문집
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• pp.351-358
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• 2001

In this study, for the investigation of effects of several parameters, such as fluid mesh boundary size, cylinder or block shape, dimensions of depth, breadth and length at free suface, and fluid mesh element size to the depth direction on a reliable shock response of finite element model under underwater explosion with consideration of the bulk cavitation analysis of a simplified surface ship was carried out using the LS-DYNA3D/USA code. The shock responses were not much affected by the fluid mesh parameters. The computational time was greatly dependent on the number of DAA boundary segments. It is desirable to reduce the DAA boundary segments in the fluid mesh model, and it is not necessary to cover the fluid mesh boundary to or beyond the bulk cavitation zone just for the concerns about an initial shock wave response. It is also the better way to prefer cylinder type of the fluid mesh model to the block one.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.827-828
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• 2006

This paper presents a vehicle control algorithm for Personal Rapid Transit (PRT) system. PRT system is a one-way direction network system which is composed of guideway branches, merging/diverging points. Vehicle control algorithm can be divided into two kinds. Those are merging control algorithm and the other. We emphasized on the merging control algorithm. For that, we first devised a front/virtual front vehicle finding strategies. Properly determined front/virtual front vehicle is the starting point of vehicle control. The objects of merging control are to avoid collision and to pass the merging point fluently. Which implies that jerk constraint and limits of acceleration and deceleration etc. are should be considered. To verify the validation of the vehicle algorithm, we executed simulations and presented test results.