• Journal of IKEEE
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• v.17 no.3
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• pp.352-359
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• 2013

This paper proposes an entropy coding unit for H.264/AVC baseline profile. Entropy coding requires code tables for macroblock encoding. There are patterns in codewords of each code tables. In this paper, the patterns between codewords are analyzed to reduce the hardware cost. The entropy coding unit consists of Exp-Golomb unit and CAVLC unit. The Exp-Golomb unit can process five code types in a single unit. It can perform Exp-Golomb processing using only two adders. While typical CAVLC units use various code tables which require large amounts of resources, the sizes of the tables are reduced to about 40% or less of typical CAVLC units using relationships between table elements in the proposed CAVLC unit. After the Exp-Golomb unit and the CAVLC unit generate code values, the entropy unit uses a small size shifter for bit-stream generation while typical methods are barrel shifters.

• Economic and Environmental Geology
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• v.48 no.3
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• pp.241-246
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• 2015

Helicobacter pylori is an important transmissible human pathogen found on the luminal surface of the gastric epithelium. The organism can persist in the stomach indefinitely and causes gastroduodenal inflammation that may proceed to atrophic gastritis, peptic ulcer, gastric MALT lymphoma, and gastric cancer. Standard triple therapy which consists of proton pump inhibitor (PPI) plus two antibiotics (amoxicillin and clarithromycin) is now generally used in Korea, however, eradication rates of H. pylori has been decreasing due to increasing antibiotic resistance. In this review, current second-line treatment regimens, difficult problems on treatment, necessity of local target therapy, applicability of clay minerals as a drug delivery system (DDS), and a new therapeutic strategy and its study plans will be discussed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.417-418
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• 2006

CATIA V5 is one of the most preferred softwares in product design for domestic and industrial use. But with the development of the IT industry, design data by CATIA V5 can easily be hacked and stolen especially via the internet and through assistance storage medium. The design data could be protected through executive, physical and technical security system. The best way to maintain confidentiality of data from unauthorized access is to have a cryptosystem of the technical security. In this paper, a cryptosystem for the protection of design data was being proposed. The memory contains the file information made by the New and Open function of CATIA V5. No error can be expected even if the file changed before of after the application of Save and Open function, A cryptosystem was constructed in CATIA V5 by inserting crypto algorithm before and after the I/O process. The encryption/decryption algorithm of each function was based on the complex cipher, which applied permutation cipher and transpose cipher. The file security system was programmed in CAA V5 and Visual C++.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.267-268
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• 2006

Cam mechanisms are one of the most popular devices for generating irregular motion and are widely used in many industrial areas. The purpose of this study is the development of high precision measuring system fur measurement data acquisition and analysis of a manufactured cam profile. The developed system is composed of servo motor, CNC controller, rotary encoder, and laser interferometer And also, this system is non-contact measuring type. The developed system takes only 5 minutes to measure a cam profile and to analyze the measuring data while the CMM(coordinate measuring machine) takes about 1 hours even by a skilled operator.

• Electronics and Telecommunications Trends
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• v.20 no.4 s.94
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• pp.120-128
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• 2005

인터넷 환경이 급속도로 발전함에 따라 멀티미디어의 범람과 사용자들의 유료 콘텐츠사용에 대한 인식 부족으로 디지털 콘텐츠의 지적재산권 침해가 빈번하게 발생하고 있으며, 이러한 불법콘텐츠들의 무분별한 공유는 디지털콘텐츠 산업 발전을 저해하는 심각한 문제로 대두되고 있다. 이에 따라 최근 디지털 콘텐츠의 저작권 보호를 위해서 저작권 단속활동을 강화하고 있으며 다양한 P2P/웹하드 환경에서도 불법콘텐츠를 검색및 다운로드하고 콘텐츠를 식별하고 불법배포자를 추적할 수 있는 기술을 필요로 하게되었다. 그러나 대부분의 불법콘텐츠들은 약 80%가 P2P, 웹하드, 동호회/카페를 통해서 전파되고 있으며 각 업체별 클라이언트 프로그램의 다양성 때문에 불법콘텐츠의 검색 및 불법복제자 추적이 매우 어려운 실정이다. 불법콘텐츠의 추적 및 차단을 위해 워터마킹/핑거프린팅, 네트워크 모니터링, 매크로 프로그램, 공개 P2P 프로토콜 조작, 페이크 파일 유포 등의 기술들이 사용되고 있다. 본 고에서는 불법콘텐츠 국내외 시장현황과 업체의 기술동향을 살펴보고 불법배포자 추적을 위해 필요한 핑거프린팅과 특징점 기반 콘텐츠 식별 기술에 대해 설명한다. 그리고 P2P와 웹하드에서 불법콘텐츠들을 자동으로 다운로드하고 불법배포자들을 추적할 수 있는 시스템 아키텍처에 대하여 설명한다.

• Communications of Mathematical Education
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• v.30 no.3
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• pp.281-294
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• 2016

This study deals with the content that was developed by the authors and the utilization of the 'Interactive Engineering Math Laboratory (IEmath Lab).' IEmath Lab provides online review lectures as well as a wide range of examples and exercises from the curriculum of engineering mathematics courses. The lectures come with pre-coded Python-based SageMath cells through which students can run and modify the code directly from this free laboratory. IEmath Lab is accessible via mobile devices so that the students can use it anywhere, anytime for maximum learning effectiveness and achievement. IEmath Lab would be an ideal tool for the effective learning and teaching of engineering mathematics, which combines theory and practice.

• Journal of the Korean Society for Nondestructive Testing
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• v.22 no.5
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• pp.508-515
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• 2002

The characterization of adhesive property in multi-layer materials has been hot issue for a long time. In order to evaluate adhesive properties, we constructed fully automated system for the backward radiation of leaky Lamb wave. The backward radiation profiles were obtained for the bare steel plate and plates with rubber-loading. The rf waveforms and frequency spectra of backward radiation show the characteristics of involved leaky Lamb wave modes. As the thickness of rubber-loading increased, the amplitude of profile at the incident angle of $13.4^{\circ}$ exponentially decreased. Scanning the incident position over the partially rubber-loaded specimen shows good agreement with the actual rubber-loading. The backward radiation of leaky Lamb wave has great potential to evaluate the adhesive condition as well as material properties of plates.

• 한국HCI학회:학술대회논문집
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• 2006.02b
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• pp.197-202
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• 2006

본 연구에서는 휴대폰에서의 효과적인 사진 검색을 지원하기 위해 사진 정보를 이용한 검색 기능을 개발하고, 이의 사용성 평가 실험을 수행함으로써 개발된 검색기능의 효용성을 검증하였다. 본 연구에서 개발한 사진 검색 기능은 크게 날짜 검색기능과 키워드 검색 기능의 두 가지로 구분된다. 날짜 검색 기능은 입력한 날짜에 해당하는 사진이 포함된 화면을 사용자에게 제시하는 방식이며, 키워드 검색 기능은 사용자가 입력한 키워드가 포함된 파일 이름을 갖는 사진을 검색하여 그 결과를 제시하는 방식이다. 개발된 검색 방식과 기존의 사용자 조작에 따른 화면 네비게이션을 통한 검색 방식을 대상으로 사용성 평가 실험을 수행하였다. 또한, 휴대폰에 저장된 사진 장수에 따른 작업의 수행도 및 주관적 만족도를 비교 분석하기 위하여, 120, 240, 360 장의 사진을 저장하고 있는 프로토타입을 개발하여 사용성 평가 실험에 활용하였다. 사용성 평가 실험 결과, 사진 장수가 120, 240 장일 경우는 날짜 검색과 키워드 검색의 두 방식이 검색 편의성, 기능의 적합성, 전반적 만족도 등의 주관적 만족도 측면에서 기존 검색 방식에 비하여 우수한 사용성 수준을 갖는 것으로 분석되었다. 사진 장수가 360 장인 경우, 날짜 검색과 키워드 검색의 활용시 검색 편의성, 기능의 적합성, 전반적 만족도가 기존 검색 방식에 비하여 우수한 성능을 갖는 것으로 분석되었고, 특히, 키워드 검색을 활용한 경우 검색 시간이 기존 검색과 날짜 검색을 활용한 경우에 비하여 우수한 성능을 갖는 것으로 확인되었다. 본 연구는 화면 크기가 작고 입력 방식이 제한된 휴대폰 인터페이스 환경에서 효과적인 사진 검색방식을 제안하고 검증하였다는 데 의의를 가진다. 본 연구 결과는 휴대폰 메뉴 검색, 일반 파일 검색 뿐만아니라 디지털 카메라의 사진 관리 기능에도 응용될 수 있을 것으로 기대된다.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.3
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• pp.336-340
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• 2010

Flash storages are prevalent as portable storage in computing systems. When we consider the detachability of Flash storage devices, data integrity becomes an important issue. To assure extreme data integrity, file systems synchronously write all file data to storage accompanying hot write references. In this study, we concentrate on the effect of hot write references on Flash storage, and we consider the effect of absorbing the hot write references via nonvolatile write cache on the performance of the FTL schemes in Flash storage. In 80 doing, we quantify the performance of typical FTL schemes for workloads that contain hot write references through a wide range of experiments on a real system environment. Through the results, we conclude that the impact of the underlying FTL schemes on the performance of Flash storage is dramatically reduced by absorbing the hot write references via nonvolatile write cache.

• Journal of KIISE
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• v.42 no.4
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• pp.427-433
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• 2015

The rapid advancement of computing technology has triggered the need for fast data I/O processing and high-performance storage technology. Next generation memory technology, which we refer to as new memory, is anticipated to be used for high-performance storage as they have excellent characteristics as a storage device with non-volatility and latency close to DRAM. This research proposes NTL (New memory Translation layer) as a technology to make use of new memory as storage. With the addition of NTL, conventional I/O is served with existing mature disk-based file systems providing compatibility, while new memory I/O is serviced through the NTL to take advantage of the byte-addressability feature of new memory. In this paper, we describe the design of NTL and provide experiment measurement results that show that our design will bring performance benefits.