• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.4 no.1
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• pp.20-27
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• 1993

In this paper, a model of TCM / M-PSK with set partitioning and a model of the combined M-ary PSK system with pragmatic coding for digital radio communication are realized. The equations of error probability for TCM / M-PSK system and the combined M-ary PSK system with pragmatic coding are derived on the conditions of the Rayleigh fading with the AWGN. It is found that the combined M-ary PSK systemwith pragmatic coding in the AWGN channel can not be applied to the fading channel since uncoded bits cause parallel:parallel paths in the trellis diagram to degrade the performance of the system. However, the use of pragmatic coding in the AWGN channel could simplify the given system since single convolutional encoder / decoder is required.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.3
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• pp.55-58
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• 2004

Recently the examples of a lighting design with LED source have increased rapidly, but there are few researches that are related to selecting luminous colors by LED. The research is that respondents operated color blender and got preference colors according to what they made, the colors were measured by chroma meter and marking CIE 1931 chromaticity diagram. Through the results of the research has made group preference for luminous colors. From now on, not only does it seem capable of using a designing a building-lighting to which LED but it will be actively applied to controlling with a digital technology for lighting design.

• Progress in Superconductivity
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• v.7 no.2
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• pp.109-113
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• 2006

The Arithmetic Logic Unit (ALU) is a core element of a computer processor that performs arithmetic and logic operations on the operands in computer instruction words. We have developed and tested an RSFQ multi-bit ALU constructed with half adder unit cells. To reduce the complexity of the ALU, We used half adder unit cells. The unit cells were constructed of one half adder and three de switches. The timing problem in the complex circuits has been a very important issue. We have calculated the delay time of all components in the circuit by using Josephson circuit simulation tools of XIC, $WRspice^{TM}$, and Julia. To make the circuit work faster, we used a forward clocking scheme. This required a careful design of timing between clock and data pulses in ALU. The designed ALU had limited operation functions of OR, AND, XOR, and ADD. It had a pipeline structure. The fabricated 1-bit, 2-bit, and 4-bit ALU circuits were tested at a few kilo-hertz clock frequency as well as a few tens giga-hertz clock frequency, respectively. For high-speed tests, we used an eye-diagram technique. Our 4-bit ALU operated correctly at up to 5 GHz clock frequency.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.70.1-70.1
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• 2011

We have investigated properties of merging galaxies in the nearby universe, using Sloan Digital Sky Survey (SDSS) DR7. We first constructed two galaxy samples according to redshift range: Sample 1 for 0 ${\leq}$ z ${\leq}$ 0.025 and Sample 2 for 0.09 ${\leq}$ z ${\leq}$ 0.1. We then identified 118 and 184 merging galaxies among the galaxies in the Sample 1 and 2, respectively, and classified them into different merging types and stages by visual inspection of galaxy images. In the Sample 1, there are more wet mergers than dry mergers, while most merging galaxies in the Sample 2 are dry mergers. The color-magnitude diagram of the merging galaxies in our samples is comparable to that of normal galaxies. Dry mergers tend to locate in the red sequence, while wet and mixed mergers reside mostly in the blue cloud. Unlike some previous studies, we did not find a clear trend that the merger rate increases at higher redshift. However, it is difficult to make a direct comparison of the merger rate found in different studies, because it depends on the number of observed galaxies and criteria for merger classification. From the ratios of emission lines, we infer that the faction of merging galaxies with AGNs is higher in wet mergers than in other types.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.11
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• pp.1174-1182
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• 1990

A hgih efficiency and good dynamic performance drive system of an induction motor is presented in this paper using vector control technique. If the induction motor is driven under light loads with rated flux, the iron loss is excessively large compared with the copper loss, resulting in poor motor efficiency. High efficiency drive of an induction motor can be achieved by adjusting the flux level which leads the total motor loss to be a minimum value. Generally reducing the flux degrades the dynamic performance, but the dynamic performance of the proposed system is also maintained high. If the d-axis is coincident with rotor flux phasor in synchronous rotating reference frame, the stator current can be decoupled as flux component and torque component. At steady state, the developed motor torque is proportional to the product of the flux and torque component. The combination of the two components minimizing the motor loss could be found with numerical method. As the procedure to obtain the optimal combination is too hard, it is found experimentally. The system block diagram is suggested for maximum efficiency control. The proposed system is studied through digital simulation and verified with experiment. The experimental results show the possiblity of a high efficiency drive with good dynamic performance of maximum efficiency control.

• Journal of Korean Society for Geospatial Information Science
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• v.8 no.2 s.16
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• pp.71-78
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• 2000

In these days, the attributes data recorded in computerization of cadastral maps is just written in its own format, not considered the relation with graphic data. Therefore, digital information linked attribute data to graphic data is necessary to be performed as fundamental data of graphic information and analysis of various spatial information. This study is to present the possibility of GIS application by constructing cadastral information related to graphic and attribute Information based on the cadastral map. Attribute information was constructed as a relational database form using data modeling and entity-relationship diagram. Thus, this study is expected to be used as a fundamental data for various public planning and design including the effective management of cadastral information and building parcel based land information system by presenting various spatial analysis and application methods.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.8
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• pp.549-555
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• 2011

For a $CO_2$ one-stage twin rotary compressor, a T-shaped suction port was used to effectively supply the suction gas stream into two individual suction chambers of the twin cylinders. Suction gas pulsations were observed in the pressure sensor signals and these were simulated by using the acoustic modeling of Helmholz resonators in parallel. The module of acoustic modeling was combined to a computer simulation program for the compressor performance. Validation of the simulation program has been carried out for a bench model compressor in a compressor calorimeter. Cooling capacity and the compressor input power were reasonably well compared between the simulation and the calorimeter test. Particularly, good agreement on P-V diagram between the simulation and the test was obtained.

• Journal of the Korea Society of Computer and Information
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• v.8 no.3
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• pp.80-86
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• 2003

XML is being watched with keen interest for the communication and saving of information. Information represented in XML provides more accuracy and a higher-speed of reference after the process of being implication. But, it is difficult that XML document is exchanged or shared in different area such as electronic commerce or digital library. Because, XML document is being different in syntax but similar in logic, with using structured difference analysis. In this thesis, we converted object-oriented class diagram to XML DTD and designed an index mechanism based on the structure information for the converted XML DTD. With our methods, we could effectively and lastly retrieve the specific element and respect to usefully access element by simple operations.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.687-688
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• 2011

This paper presents a design method for combinational digital logic systems using time domain based multiplexing(TDBM) and common multi-terminal extension decision diagrams(CMTEDD). The proposed method can reduce the 1)hardware, 2)logic levels and 3)pins. In the logic system design, we use two types of decision diagrams(DDs), that is the common binary decision diagrams(CBDDs) and CMTEDDs. Also, we propose an algorithms to derive common multiple-terminal binary decision diagrams(CMTBDD) from CBDDs, and CMTEDDs from CMTBDDs. The CMTEDDs over CBDDs is more compactness in terms of number of non-terminal nodes, where the nodes for output selection variables are not included in the non-terminal nodes. In the logic design, each non-terminal nodes of an CBDDs and an CMTEDDs is realized by a multiplexer(MUX). In addition, we compare the proposed TDBM realization with the conventional one.

• Journal of Korea Multimedia Society
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• v.24 no.3
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• pp.460-467
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• 2021

Among the formative elements, color and form are the most critical elements that can capture a person's perspective. Companies are concentrating on developing visual perception-oriented products by accommodating the diverse needs of consumers, where the emotional factor plays as an important design consideration. Accordingly, the visual perception reaction of consumers was analyzed through a questionnaire focusing on color and form. The result finds that, when Ernst Gombrich (1909-2001) perceives objects in questionnaires related to personal preferences for color and form, humans do not rely solely on the eyes, but describes with the knowledge diagram through that knowledge. In doing so, the knowledge that we already know plays a part to describe the object. In addition, colors and forms are recognized by combining the social and cultural information experiences of the perceiver with the learned knowledge. In the future studies that define the interrelationships of the formative elements should be continued through the analysis of more complex and clear visual perception characteristics of the formative elements.