• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 추계학술대회
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• pp.281-283
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• 2009

본 논문에서는 군집 소실 채널 상에서 동작할 수 있는 짧은 길이의 인터리빙 된 코드들의 성능을 분석한다. 먼저 좋은 성능을 갖는 짧은 길이의 그래프 부호와 해밍부호를 설계한다. 이 후 군집 소실에 잘 대응하기 위하여 인터리빙 기능을 채널 부호화 방법에 적용한다. 생성된 짧은 코드에 적용한 인터리빙 부호를 군집 소실에 최적의 성능을 보이는 Reed-Solomon (RS) 부호와 성능을 비교한다. 짧은 길이의 부호이므로, ML(Maximum Likelihood)방법과 BP(Belief propagation)의 두 가지 복호 방법들을 이용한 경우 성능의 차이 또한 비교해 본다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.239-242
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• 2000

The purpose of this paper is to establish an effective inspection system by using OMM(ON-Machine Measurement) system. This allows us to reduce the manufacturing lead time by separating the inspection process from manufacturing system. As a first step, the inspection process planning is accomplished by determining the number of measuring points, their locations, measuring path and their sequence. Subsequently, we generate measuring G-codes to be transferred to the machining center through RS232C, and then the inspection process will be performed for each shape. Analysing obtained measuring data, the dimensional tolerance will be validated.

• Clinical and Experimental Reproductive Medicine
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• 제46권3호
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• pp.132-139
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• 2019

Objective: Vitamin D-binding protein (VDBP) mediates various biological processes in humans. The goal of this study was to investigate whether VDBP gene polymorphisms could predispose Korean women to endometriosis. Methods: We prospectively enrolled women with endometriosis (n = 16) and healthy controls (n = 16). Total serum 25-hydroxyl vitamin D (25(OH)D) concentrations were measured using an Elecsys vitamin D total kit. Levels of bioavailable and free 25(OH)D were calculated. Concentrations of VDBP were measured using a vitamin D BP Quantikine ELISA kit. DNA was extracted using a DNeasy blood & tissue kit. Two single-nucleotide polymorphisms (SNPs; rs4588 and rs7041) in GC, the gene that codes for VDBP, were analyzed using a TaqMan SNP genotyping assay kit. The functional variant of VDBP was determined based on the results of the two SNPs. Results: Gravidity and parity were significantly lower in the endometriosis patients than in the control group, but serum CA-125 levels and the erythrocyte sedimentation rate were significantly higher. Total serum 25(OH)D levels in the endometriosis patients were significantly lower than in the control group. However, serum bioavailable 25(OH)D, free 25(OH)D, and VDBP levels did not differ significantly between the endometriosis and control groups. The genotypes and allele frequencies of GC were similar in both groups. Conclusion: Korean women with endometriosis had lower total serum 25(OH)D concentrations than controls. Neither serum VDBP concentrations nor polymorphisms in the gene coding for VDBP were associated with endometriosis. Further studies are needed to investigate the pathophysiology and clinical implications of 25(OH)D and VDBP in endometriosis.

• 한국위성정보통신학회논문지
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• 제8권4호
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• pp.21-25
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• 2013

최근 지상파 방송에서 듀얼스트림 방식을 사용한 HD급의 3D 방송서비스가 시작되어 많은 관심이 이어지고 있다. 2011년 12월에 듀얼스트림 방식의 지상파 3DTV 송수신 정합 표준이 제정되고, 2012년 10월 시범방송이 실시되는 등 국내 기술이 3D HDTV 서비스를 선도하고 있는 상황이다. 하지만, 안정적인 HD급의 지상파 방송에서 3D 방송서비스(이하 3D HDTV)를 제공하기 위해서는 보다 데이터 전송률을 높이는 전송이 필요하다. 본 논문에서는 Reed Solomon 부호와 블록 LDPC 부호를 사용하고 16QAM 변조를 사용하여 기존 방식과 비교하여 전송 용량을 증대할 수 있다는 사실을 확인하였다. AWGN 채널에서 모의 실험한 결과 기존의 ATSC 송수신 정합표준, 수정된 ATSC 전송방식[2]과 비교하여 각각 2.97dB, 1.12dB 가량의 SNR 이득이 있음을 확인하였고, 3D HDTV 서비스의 안정적인 서비스를 위해 요구되는 29Mbps의 데이터 전송률로 전송이 가능하여 기존시스템에 비해 약1.5배의 전송용량 증대가 가능한 것으로 확인되었다. 이로서 6MHz의 한정된 대역에서 HD급의 3D 방송서비스의 성능 개선이 가능할 것으로 예상된다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.423-426
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• 2005

In this paper, we propose a receiver that combines a channel detector with a channel decoder to retrieve information from ISI and AWGN in an iteratively manner. The receiver, evolving from a system of a PRML detector and a RS decoder, consists of a SOVA detector followed by a LDPC decoder and has them exchange information iteratively. Rather than handling extrinsic reliabilities explicitly as in Turbo equalization, we take hard-decision values from the LDPC decoder and mix them with the channel output in a certain ratio as input for SOVA. The scheme, simply modified to the one-way structure of a SOVA and a LDPC decoder, shows improved performance with iteration numbers as well as the combining ratio of the channel output and the feedback output. We additionally analyze the receiver with a simple theoretical model and present some valuable properties.

• 한국CDE학회논문집
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• 제4권4호
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• pp.339-349
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• 1999

The punose of this paper is to introduce the comprehensive CAM system (called PosCAM) supporting various function requested from shop floor operators. PosCAM is comported of two subsystems (PosCAM I and PosCAM II) which are designed to make up for the contemporary CAD/CAM systems. PosCAM I is mainly for : a) verifying the part programs written in both custom macros and standard G-codes, b) enhancing machining productivity and quality with built-in cutting conditions and feedrate optimization algorithm. PosCAM II is for : a) efficiently managing the numerous part programs and tool data stored in CNC memory, and b) integratively controlling and monitoring various CNCs from the control center through RS-422 with DNC 2 protocol. The developed systems have been tested via various experiments, and can be Applied for the industrial CNC machine shop as a means for enhancing productivity. The PosCAM system has been implemented and successfully used in the Machine Shop Department of PosCAM since march 1998.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2012년도 하계학술대회
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• pp.134-137
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• 2012

최근 ATSC방식의 디지털 방송에서 HD급의 3D 방송 서비스에 대한 관심이 증가 되고 있는 추세이다. HD급의 3D 방송 서비스(이하 3D HDTV)를 제공하기 위해 [2]에서는 ATSC 전송 시스템을 확장하고 BCH 부호와 IRA 타입의 LDPC를 사용하는 수정된 ATSC 전송 시스템을 제안하였다. 본 논문에서는 BCH와 IRA 타입의 LDPC 부호 대신 Reed Solomon 부호와 Block LDPC 부호를 사용하고 16QAM 변조를 사용하여 전송 용량을 증대할 수 있다는 사실을 확인하였다. AWGN 채널에서 모의 실험한 결과 BCH부호와 LDPC부호 및 4PAM을 적용한 수정된 ATSC 전송시스템의 TOV는 약 7dB로 19.33Mbps로 전송되지만[2] 본 논문에서 제안한 RS(207, 187)과 부호율 3/4인 Block LDPC 및 16QAM의 TOV는 약 5.4dB로 29Mbps로 전송되어 기존시스템에 비해 약1.5배의 전송 용량 증대가 가능한 것으로 확인되었다. 이로서 6MHz의 한정된 대역에서 HD급의 3D 방송서비스 실현이 한층 더 가까워지게 될 것으로 예상된다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권10호
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• pp.5144-5160
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• 2019

Secret sharing is an effective way of protecting secret messages. However, the traditional secret sharing schemes are considered meaningless due to malicious people attention which might raise risks. To overcome the weakness, this paper presents an effective secret sharing scheme with the functionality of cheater identification, based on meaningful QR code. The secret message will be split and concealed in the padding region of cover QR codes with the assistance of Latin square and it can be completely restored when all the involved participants cooperate. The concealing strategy exploits the characteristic of Reed-Solomon (RS) code to ensure the strong robustness of generated QR code pseudo-shares. The meaningful QR code pseudo-shares help to reduce the curious of unrelated persons. Some experiments were done to evaluate the performance of proposed scheme. The results showed that the proposed scheme is feasible, efficient and secure compared to the other existing schemes. It also achieves a higher secret payload and maintains stronger robustness.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권5호
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• pp.1744-1765
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• 2014

A client stores data in the cloud and uses remote data checking (RDC) schemes to check the integrity of the data. The client can detect the corruption of the data using RDC schemes. Recently, robust RDC schemes have integrated forward error-correcting codes (FECs) to ensure the integrity of data while enabling dynamic update operations. Thus, minor data corruption can be recovered by FECs, whereas major data corruption can be detected by spot-checking techniques. However, this requires high communication overhead for dynamic update, because a small update may require the client to download an entire file. The Variable Length Constraint Group (VLCG) scheme overcomes this disadvantage by downloading the RS-encoded parity data for update instead of the entire file. Despite this, it needs to download all the parity data for any minor update. In this paper, we propose an improved RDC scheme in which the communication overhead can be reduced by downloading only a part of the parity data for update while simultaneously ensuring the integrity of the data. Efficiency and security analysis show that the proposed scheme enhances efficiency without any security degradation.

• 디지털산업정보학회논문지
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• 제15권3호
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• pp.79-87
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• 2019

The system proposed in this paper is a fully automated parking control system that can even protect users' information through blockchain. Unlike conventional parking control systems, the system consists of a web page that is accessible to people of all ages and ages, directly to the parking lot. Such a system would also benefit managers in the parking lot business. This is because it can reduce soaring labor costs and maximize the sales it can generate by operating 24 hours a day. In order to implement these systems, the web page was first designed using HTML and the API was configured using JAX-RS to invoke the API required by the web page. As a result, it created a web page that was easily accessible to anyone, built a server that could be accessed by more than 200 people at the same time, focused on personal information protection by encrypting the information of users through blockchain grafts, and designed a system that enabled users to complete payments easily. It is planning to add QR codes and GPS functions in the future and implement a function that allows one-touch information on parking lots and their vehicle information.