• The Transactions of the Korean Institute of Power Electronics
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• v.20 no.2
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• pp.122-129
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• 2015

In this study, we propose a low voltage stress and cost-effective light emitting diode (LED) driver capable of multi-channel current balancing. Conventional LED drivers require as many boost converters as the number of LED channels, whereas the proposed LED driver requires only one buck converter and several balancing capacitors instead of several expensive boost converters. Additionally, while the components of the boost converter have high voltage stress and depend on the LED driving voltage, components of the proposed driver have about one-half of the voltage stress across all components. The proposed driver exhibits high reliability and cost effectiveness because it only uses few DC blocking capacitors with no additional active devices to balance the current of multi-channel LEDs. The proposed driver exhibits high reliability and cost effectiveness. The validity of the proposed driver is confirmed through a theoretical analysis. An explanation of the design considerations and experimental results were obtained using a prototype applicable to a 46" LED-TV.

• Progress in Superconductivity
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• v.4 no.2
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• pp.127-131
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• 2003

We have designed and measured an SFQ(Single Flux Quantum) OR gate for a superconducting ALU (Arithmetic Logic Unit). To optimize the circuit, we used WRspice, XIC and Lmeter for simulations and layouts. The OR gate was consisted of a Confluence Buffer and a D Flip-Flop. When a pulse enters into the OR gate, the pulse does not propagate to the other input port because of the Confluence Buffer. A role of D Flip-Flip is expelling the data when the clock is entered into D Flip-Flop. For the measurement of the OR gate operation, we attached three DC/SFQs, three SFQ/DCs and one RS Flip -Flop to the OR gate. DC/SFQ circuits were used to generate the data pulses and clock pulses. Input frequency of 10kHz and 1MHzwere used to generate the SFQ pulses from DC/SFQ circuits. Output data from OR gate moved to RS flip -Flop to display the output on the oscilloscope. We obtained bias margins of the D Flip -Flop and the Confluence Buffer from the measurements. The measured bias margins $\pm$38.6% and $\pm$23.2% for D Flip-Flop and Confluence Buffer, respectively The circuit was measured at the liquid helium temperature.

• Fashion & Textile Research Journal
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• v.6 no.2
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• pp.153-162
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• 2004

Influenced by Constructivism Art, Constructivism theatre projected the future with the help of participating artists and the development of new technologies. Therefore, this thesis studied the stage costumes in the plays of Meyerhold who represented Constructivism Play and showed its characteristics. The stage costumes in Meyerhold's plays followed the rules of Constructivism Play and showed several unique characteristics, such as the Bio-mechanic as a characteristic in his plays, functionality that facilitated the movement based on Taylorism, simple shapes, and easy cutting. Constructive artists saw the stage of constructive plays as a laboratory where they can display their designs, directly portraying future life forms through stage costumes and props. Stage costumes were no more a supporting tool that had described the play. Following the new concept of stage costumes, working costumes and stage costumes came to be regarded as the same. In turn, this led to new models and special costumes such as sportswear or specialized garments. Constructivism artists foresaw the future through the plays, with their fundamental basis for stage costumes shown in the later works of ordinary costumes.

• Fashion & Textile Research Journal
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• v.11 no.6
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• pp.887-895
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• 2009

The purposes of this study were to provide informations to apparel companies and to contribute the education of clothing consumers through finding out the present status of clothes purchasing behaviors and the degree of the recognition and the application of care labels of the Chinese students in Daegu area. The data were collected from 166 Chinese students through the questionnaire and analyzed by the frequence, t-test, ANOVA, and Scheffe-test using SPSS 12.0. The results were as follows: 1. The main purchasing place was road shops of well-known brands, and the most decisive factor of purchasing was the display style of goods. They purchased 'any time when necessary' and impulsively. They payed mostly by cash and the most affecting factor of purchasing decision was the degree of fitting. 2. The recognition of the necessity of care label was found in 36.7% of respondent and their most rationale was 'for the management of clothes'. The recognition of care labels showed the highest in reliability and the lowest in application. There were significant differences in satisfaction of care label between male and female and in application according to purchasing places. In conclusion, the recognition of the necessity of care labels showed a little high level but relatively low in the understanding and the application.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.1
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• pp.18-25
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• 2003

A haptic hand controller (HHC) operated by the user’s hand can receive information on position and orientation of the hand and display force and moment generated in the virtual environment to the hand. In this paper, a 3-DOF hand controller is first presented, in which all the actuators are mounted on the fixed base by combining a 5-bar linkage and a gimbal mechanism. The 6-DOF HHC is then designed by connecting these two 3-DOF devices through a handle which consists of a screw and nut. Analysis using performance index is carried out to determine the dimensions of the device. The HHC control system consists of the high-level controller for kinematic and static analysis and the low-level controller for position sensing and motor control. The HHC used as a user interface to control the mobile robot in the virtual environment is given as a simple application.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.7
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• pp.761-768
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• 2011

The large surface micro machining system includes the equipments and processes for manufacturing the ultra precision micro patterned products with large surface through the mechanical machining. Recent major issue on the micro machining technology may be the development of optical parts for the back light unit of display which has the largest market. This special issue makes up with three parts; the large surface micro machining system and machine, machining process and forming process. In this paper, the state-of-the-art and core technology of large surface micro machining system is introduced with focus on the manufacturing technology for the back light unit of LCD TV. Then, some research results on the development of a roll die lathe is introduced which involves the concept of machine design, improvement of thermal characteristics in the spindle system, improvement of relative parallelism and straightness between spindle system and long stroke feed table, machining of micro pitch patterns. Finally, the direct forming process is introduced as the future work in the large surface micro machining field.

• Journal of the Korean Society for information Management
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• v.24 no.3
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• pp.149-178
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• 2007

The purpose of this study is to analyze and evaluate the characteristics of online catalogs' interface of elementary school libraries, and to propose how to design user-friendly interfaces. The online catalogs of elementary school libraries are categorized into 6 types. Such topics as the features of search methods, the record display formats, the terminology usage, and the special features of the 6 types are discussed. Some shortcomings are examined and how to improve them is suggested.

• Journal of Internet Computing and Services
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• v.5 no.4
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• pp.43-51
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• 2004

The convergence of mobile communications and handheld computers offers the opportunity to develop technology that will assist individuals and groups to learn anytime, anywhere. In this thesis, we suggest a learning model for educational mobile contents, and implement a mobile contents for English vocabulary learning. The mobile contents consist of two parts: vocabulary learning and vocabulary evaluation. The vocabulary learning provides the mobile learner not only the display of English vocabulary but also the pronunciation of native speaker. The degree of learning achievement is evaluated by the quiz program of game style. Accordingly, the proposed prototype system for English vocabulary learning is designed and implemented, as an exemplar of personal mobile systems for edutainment mobile learning.

• Proceedings of the KOSOMBE Conference
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• v.1994 no.12
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• pp.85-87
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• 1994

In this paper, we present an object-oriented stereotactic radiosurgery planning system, which accepts medical images such as CT and angiography, transforms the coordinates to a reference frame coordinate, calculates dose distributions, and finally displays isodose curves over the images. The user finds an adequate one for radiosurgeries after performing computer simulations on different treatment parameter sets. The object-oriented design concept was fully applied to the system composed of seven manager objects of different classes: a patient information manager, a user-interface manager, a coordinate transformation manager, a blackboard manager, a dose calculation manager, an isodose curve display manager, and a report manager. All the user interactions are carried out through the use of mouse buttons. The performance of the system was verified by four physicians and two medical physicists, and now is being used in two clinical sites.

• Proceedings of the Korea Multimedia Society Conference
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• 2002.11b
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• pp.507-510
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• 2002

웹에서 이용할 수 있는 Annotation들은 개인 노트의 수단이며, 같은 일에 종사하는 동료들간의 커뮤니케이션과 협업할 수 있도록 도와준다. 이런 종이 책에서의 Annotation들을 웹에 적용함으로써 공유. 검색, 재편집 등의 장점을 얻을 수 있다. 웹 Annotation은 통신수단의 발달과 함께 증가한 인터넷 사용자들의 활발한 커뮤니케이션을 통해 빠르게 증가하고 있어 한 문서에 많은 Annotation이 생성된다. 현재, 웹 상의 Annotation에 관련된 연구들은 생성, 출력, 저장을 중심으로 연구되고 있으나 한 문서 또는 한 Anchor에 존재하는 많은 Annotation들을 효과적으로 제공하는 방법에 관한 연구는 미비한 실정이다. 기존 Annotation 시스템들의 대부분은 다수의 Annotation들을 관련성이나, 사용자 특성을 고려하지 않고, 입력된 순서로 Annotation을 제공한다. 때문에 Anchor의 이해시간을 가중시킨다. 또한, 생성된 모든 Annotation 제공으로 인해 문서에 너무 많은 Annotation들이 생성되어 문서의 레이아웃을 손상시킬 수 있어[1], 문서를 이해의 시간을 증가시킨다[2]. 따라서 본 논문에서는 웹 문서에 생성된 다수의 Anchor들과 Annotation들을 사용자에게 효율적으로 제공하기 위하여 사용자 관심사에 맞는 Anchor와 Annotation만을 제공하는 Annotation 필터링기법을 제안한다. 또한. 동일한 Anchor내에서 적절한 Annotation의 우선 접근을 위한 Annotation 순위 부여기법과 Annotation 필터링 결과에 따라 Anchor의 표현유무를 결정하는 Anchor 표현 기법을 제안한다.