• Proceedings of the KIEE Conference
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• 2006.05a
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• pp.78-82
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• 2006

The Partial Discharge Monitoring System is technology which is available to measure & analysis the partial discharge of Power equipment. This technology is in the limelight as a pre-forecast system of equipment defect but there are some problems like no protocol standard, layered network management and the limitation of physical size. This paper presents whole system structure includes engineering centers, LN(Logical Node) to apply PDMS for, base-digital substation system, ICE61850 compatible Condition Monitoring &Diagnosis (CMD), Local Unit(LU), Intelligent Electronic Device (IED) for the solution scheme of these limitations.

• Journal of Information Management
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• v.35 no.2
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• pp.107-130
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• 2004

MPEG-21 is an open standard framework for creation, delivery and consumption of digital content in interoperable and rights-managed and protected way. Focusing on DRM technologies, this paper covers with concept and ongoing activities of MPEG-21's parts - Digital Item Declaration which is the base unit of trade and delivery, Digital Item Identification, Intellectual Property Management & Protection, Rights Data Dictionary, Rights Expression Language, Persistent Association Technology, Event Reporting, and so on.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.587-592
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• 2002

A new digital correlator fur an airborne synthetic aperture radiometer was designed in order to replace the conventional analog correlator unit which will become very complicated while the number of channels is increasing. The digital correlator uses digital IQ demodulator instead of the intermediate frequency (IF) phase shifter to make the correlation processing performed digitally at base band instead of analogly at IF. This technique has been applied to the digital receiver in softradio. The down-converted IF signals from each pair of receiver channels become low rate base-band digital signals after under-sampled, Digitally Down-Converted (DDC), decimated and filtered by FIR filters. The digital signals are further processed by two digital multipliers (complex correlation), the products are integrated by the integrators and finally the outputs from the integrators compose of the real part and the imaginary part of a sample of the visibility function. This design is tested by comparing the results from digital correlators and that from analog correlators. They are agreed with each other very well. Due to the fact that the digital correlators are realized with the help of Analog-Digital Converter (ADC) chips and the FPGA technology, the realized volume, mass, power consumption and complexity turned out to be greatly reduced compared with that of the analog correlators. Simulations show that the resolution of ADC has an influence on the synthesized antenna patterns, but this can be neglected if more than 2bit is used.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.2
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• pp.1-11
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• 1997

We developed a base station modulator ASIC for CDMA digital cellular system. In CDMA digital cellular system, the modulation is performed by convolutional encoding and QPSK with spread spectrum. The function blocks of base station modulator are CRC, convolutional encoder, interleaver pseudo-moise scrambler, power control bit puncturing, walsh cover, QPSK, gain controller, combiner and multiplexer. Each function block was designed by the logic synthesis of VHDL codes. The VHDL code was described at register transfer level and the size of code is about 8,000 lines. The circuit simulation and logic simulation were performed by COMPASS tools. The chip (ES-C2212B CMB) contains 25,205 gates and 3 Kbit SRAM, and its chip size is 5.25 mm * 5,45 mm in 0.8 mm CMOS cell-based design technology. It is packaged in 68 pin PLCC and the power dissipation at 10MHz is 300 mW at 5V. The ASIC has been fully tested and successfully working on the CDMA base station system.

• International Commerce and Information Review
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• v.8 no.4
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• pp.3-22
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• 2006

Recently, the use of digital contents and demand have been increased with expanding users of internet. Thus, the importance of digital contents distribution site's has been increased that deal in commercially. The model that measuring acceptance of web sites is studying lively, however, the web sites that dealing and distributing specific goods to be called digital contents have insufficient theoretical base and model about acceptance of customers. Also, the research that acceptance of existing commercial web sites have limitation to explain systematically which influence on acceptance of digital contents distribution sites. Because, those research connect directly the feature of web sites, the purchase of web sites or the feature of buyers and acceptance. For that reason, it's hard to reflect the feature of digital contents. In this research, to measure customers' acceptance of web sites that distribute digital image, it is based on Technology Acceptance Model by Davis. This research find out the significant cause from survey by users of digital image distribution site. and TAM which has been adapted the analyzation of new site's acceptance can explain the state of digital image distribution site use. This research let us know the evaluation of digital image distribution site and operating strategy as a new business model.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.29
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• pp.143-172
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• 2006

This study focuses on the risk management of "Digital Goods" appeared with the progress of information technology(IT) in international transaction. As a result of that digital goods have a lot of uncertainty between the general goods or service which have been deal with object of international transaction broadly because digital goods hold uniqueness. In this study, the author give a definition of "Digital Goods" and make an examination of uniqueness of that in international transaction. Next, six risks are defined base on risk theory and risk analysis matrix applying risk mapping model is made. Conclusionally, risk transfer as insurance is adequate to manage business risk, security risk, credit risk and legal risk. Meanwhile, risk avoidance is adequate to manage reputation risk and market risk. But, this study have following three limits. Firstly, concerning definition of the risk, real case is not applied owing to lack of transaction data. Secondly, measuring of the risk is not based on absolute data but relative data. Lastly, suggesting way of risk management is not concrete and practical to international trader of digital goods.

• Journal of Korean Port Research
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• v.14 no.2
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• pp.209-217
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• 2000

This study is to develop the technology and the ways of the practical use of the integrated digital map of and Electronical Navigational Chart(ENC) and Digital Terrain Map(DTM) for the effective and scientific based conservation, development and management. In this study, as preliminary studies to make eventual integrated maps, the concept of coastal areas are defined and the characteristics of digital maps developed by Korean Geography Institute and National Marine Investigation Institute are carefully analyzed. A test coastal map was developed based on the integrated digital map, a high resolution satellite image and Global Positioning System. Results from the edge matching analysis of coastal lines shows 8 meters difference in maximum. The problems, causes and solutions for the edge matched differences are described. Furthermore, the practical value of utilization, future use and various field of application are described based on the integrated digital map data base of coastal area.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1999.10a
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• pp.347-356
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• 1999

This study is to develop the technology and the ways of the practical use of the integrated digital map of and Electronical Navigational Chart(ENC) and Digital Terrain Map(DTM) for the effective and scientific based conservation, development and management. In this study, as preliminary studies to make eventual integrated maps, the concept of coastal areas are defined and the characteristics of digital maps developed by Korean Geography Institute and National Marine Investigation Institute are carefully analyzed. A test coastal map was developed based on the integrated digital map, a high resolution satellite image and Global Positioning System. Results from the edge matching analysis of coastal lines shows 8 meters difference in maximum. The problems, causes and solutions for the edge matched differences are described. Furthermore, the practical value of utilization, future use and various field of application are described based on the integrated digital map data base of coast area.

• The Journal of Advanced Prosthodontics
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• v.12 no.6
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• pp.376-382
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• 2020

PURPOSE. To determine the shear bond strengths of different denture base resins to different types of prefabricated teeth (acrylic, nanohybrid composite, and cross-linked) and denture teeth produced by computer-aided design/computer-aided manufacturing (CAD/CAM) technology. MATERIALS AND METHODS. Prefabricated teeth and CAD/CAM (milled) denture teeth were divided into 10 groups and bonded to different denture base materials. Groups 1-3 comprised of different types of prefabricated teeth and cold-polymerized denture base resin; groups 4-6 comprised of different types of prefabricated teeth and heat-polymerized denture base resin; groups 7-9 comprised of different types of prefabricated teeth and CAD/CAM (milled) denture base resin; and group 10 comprised of milled denture teeth produced by CAD/CAM technology and CAD/CAM (milled) denture base resin. A universal testing machine was used to evaluate the shear bond strength for all specimens. One-way ANOVA and Tukey post-hoc test were used for analyzing the data (α=.05). RESULTS. The shear bond strengths of different groups ranged from 3.37 ± 2.14 MPa to 18.10 ± 2.68 MPa. Statistical analysis showed significant differences among the tested groups (P<.0001). Among different polymerization methods, the lowest values were determined in cold-polymerized resin.There was no significant difference between the shear bond strength values of heat-polymerized and CAD/CAM (milled) denture base resins. CONCLUSION. Different combinations of materials for removable denture base and denture teeth can affect their bond strength. Cold-polymerized resin should be avoided for attaching prefabricated teeth to a denture base. CAD/CAM (milled) and heat-polymerized denture base resins bonded to different types of prefabricated teeth show similar shear bond strength values.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.532-535
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• 2008

The requirement of Digital Culture Content(Movie, Music, Animation, Digital TV, Exhibition and etc.) is increasing so variety and quantity of content is also increasing. The Movie what majority of the digital Content is developing of technology and data. In the result, the efficient retrieval service has required and user want to use a recommendation engine and semantic retrieval methods through the recommendation system. Therefore, this paper will suggest analysing trait element of digital content data, building of retrieval technology, analysing and retrieval technology base on KANSEI vocabulary and etc. For the these, we made a extraction technology of trait element based on semantics and KANSEI processing algorithm based on color information.