• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (B)
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• pp.546-548
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• 2003

MPEC-7 메타데이타는 이미지의 칼라 히스토그램과 같은 멀티미디어 객체의 속성을 기술할 수 있어서, MPEG-7을 사용하는 멀티미디어 디지털도서관 시스템은 멀티미디어 객체에 대한 내용기반 검색을 가능하게 해준다. MPEC-7 메타데이타는 XML 데이터이며, 이애 대한 질의를 위해서는 XQuery와 같은 XML 데이터를 위한 질의어가 필요하다. 본 논문에서는 MPEG-7 데이터에 대한 XQuery 질의를 처리할 수 있는 XQuery 엔진을 제안한다. 엔진은 XQuery를 입력받아 정보검색을 위한 POT(Primitive Operation Tree)를 생성한다. 우리의 방식은 표준질의어인 XQuery를 처리함으로써 디지털도서관 시스템 사이의 상호 운영성을 확보할 수 있으며, XQuery 엔진과 정보검색기 사이의 표준 인터페이스로 사용할 수 있는 POT를 위한 primitive operation 집합을 정의하였으며, 또한 POT 상에서의 질의 최적화를 수행하여 검색 성능 향상을 도모하였다.

• Journal of Electrical Engineering and Technology
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• 제3권3호
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• pp.430-435
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• 2008

In the paper, an algorithm called a Constraint algorithm is proposed to solve the fan-in problem occurred in ADC encoding circuits. The Flash ADC architecture uses a double-base number system (DBNS). The DBNS has known to represent the multi-dimensional logarithmic number system (MDLNS) used for implementing the multiplier accumulator architecture of FIR filter in digital signal processing (DSP) applications. The authors use the DBNS with the base 2 and 3 to represent binary output of ADC. A symmetric map is analyzed first, and then asymmetric map is followed to provide addition read DBNS to DSP circuitry. The simulation results are shown for the Double-Base Integer Encoder (DBIE) of the 6-bit ADC to demonstrate an effectiveness of the Constraint algorithm, using $0.18{\mu}\;m$ CMOS technology. The DBIE’s processing speed of the ADC is fast compared to the FAT tree encoder circuit by 0.95 GHz.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2015년도 하계학술대회
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• pp.56-57
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• 2015

근래 3D산업의 발전으로 디지털 홀로그램 기술이 부각되고 있다. 본 논문에서는 디지털 홀로그램 영상을 쿼드트리형식으로 Fresnelet 변환을 통한 양자화기를 구현하기위해 특징 및 중요도를 분석하는 방식에 대해 제안한다. 디지털 홀로그램 영상을 Fresnelet 변환을 수행한 뒤 부대역 별로 평균에너지에 따른 에너지 분포의 순위를 정하였고, 크기에 따른 히스토그램의 결과를 이용해 향후 디지털 홀로그램 압축 및 전송 기법에 적용할 수 있는 것을 확인 하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.518-521
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• 1998

This paper describes a 3.3V-65MHz 12BIT CMOS current-mode DAC designed with a 8 MSB current matirx stage and a 4 LSB binary weighting stage. The linearity errors caused by a voltage drop of the ground line and a threshold voltage mismatch of transistors have been reduced by the symmetrical routing method with ground line and the tree structure bias circuit, respectively. In order to realize a low glitch energy, a cascode current switch ahs been employed. The simulation results of the designed DAC show a coversion rate of 65MHz, a powr dissipation of 71.7mW, a DNL of .+-.0.2LSB and an INL of .+-.0.8LSB with a single powr supply of 3.3V for a CMOS 0.6.mu.m n-well technology.

• 한국공작기계학회논문집
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• 제16권5호
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• pp.101-107
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• 2007

Assembly is mentioned as important process saving time and cost where we produce the machine with many parts relationships. In this study, parts assembly relationship is analysed for assembly information of micro milling machine which have been developing for research. Liaison diagram, datum flow chain and assembly tree are applied to discuss assembly characteristics of micro milling machine model. We can find out the characteristics of micro machine assembly and discuss about facility of assembly. Some analysis in this paper about micro milling machine will give a useful tools for assembly. We knew that the predicted results from analysis in this study are alignment and clearance among the parts. The 3D model of micro machine which is studied in this paper is not a complete model. Main parts of a micro milling machine are used and presented.

• 전자공학회논문지A
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• 제33A권6호
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• pp.206-219
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• 1996

This paper describes a data structure and evaluation algorithm to improve the perofmrances MOS logic-with-timing simulation in computation and accuracy. In order to efficiently simulate the logic and timing of driver-load networks, (1) a tree data structure to represent the mutual interconnection topology of switches and nodes in the driver-lod network, and (2) an algebraic modeling to efficiently deal with the new represetnation, (3) an evaluation algorithm to compute the linear resistive and capacitive behavior with the new modeling of driver-load networks are developed. The higher modeling presented here supports the structural and functional compatibility with the linear switch-level to simulate the logic-with-timing of digital MOS circuits at a mixed-level. This research attempts to integrate the new approach into the existing simulator RSIM, which yield a mixed-klevel logic-with-timing simulator MIXIM. The experimental results show that (1) MIXIM is a far superior to RSIM in computation speed and timing accuracy; and notably (2) th etiming simulation for driver-load netowrks produces the accuracy ranged within 17% with respect ot the analog simulator SPICE.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.553-554
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• 2015

This paper presents the selection method of Minimal Cut Sets(MCS) for substation reliability evaluation. We used the Quality solution in order to model the FT for the substation equipment. Quantitative analysis is performed to estimate the probability of top event occurrence and unreliability of the substation component. In this result, it means that reliability indices which can be predict get electricity services and better maintenance in substation management.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.655-660
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• 2000

Animation technique from the PIV database is particularly emphasized to give macroscopic and quantitative description of complex flow fields. This paper shows animation construction and application example for the post-processing of PIV data. As examples, first case is a pitching airfoil immersed in tree surface water circulating tunnel. Second case is a wake of a model-ship. Third case of PIV data is a large scale surface flow field. Obtained images are processed in time sequence by PIV exclusive routines where an efficient and reliable cross correlation algorithm is included for vector identification. All. animation Jobs are implemented completely on single personal computer environment. Compressed digital images are obtained initially by Motion-JPEG board and various An files are finally obtained through graphic processes.

• Journal of Ubiquitous Convergence Technology
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• 제1권1호
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• pp.28-34
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• 2007

Tree-based reliable multicast protocols provide scalability by distributing error-recovery tasks among several repair nodes. These repair nodes perform local error recovery for their receiver nodes using the data stored in their buffers. We propose a packet loss patterns adaptive feedback scheduling scheme to manage these buffers in an efficient manner. Under our scheme, receiver nodes send NAKs to repair nodes to request packet retransmissions only when the packet losses are independent events from other nodes. At dynamic and infrequent intervals, they also send ACKs to indicate which packets can be safely discarded from the repair node's buffer. Our scheme reduces delay in error recovery because the requested packets are almost always available in the repair node's buffers. It also reduces the repair node's workload because (a) each receiver node sends infrequent ACKs with non-fixed intervals and (b) their sending times are fairly distributed among all the receiver nodes.

• Spatial Information Research
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• 제3권1호
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• pp.19-27
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• 1995

논문에서 다룰 시스템은 영상 처리를 이용한 전처리과정에서 사용자에게 필요한 정보를 얻은 뒤 이 자료를 상호교류적으로 입력하는 반자동 지도입력시스템이다. 영상 처리는 주로 중요한 정보의 하나인 외곽선 추출에 주력하였고 이를 위해 적응성 평활화 필터와 연결보존외곽선추출를 사용하였다. 외곽선 정보는 편집기에서 벡터화 하며 편집의 효율을 높이기 위해 내부 자료구조는 확장된 사진트리 구조를 사용하였다. 이러한 작업들은 그 특성에 따라 개인용 컴퓨터와 워크스테이션에 각각 분담시켰고 네트웍을 통해 저장기기를 공유하여 작업의 일관성및 단순화를 추구하였다.