CRC를 사용한 터보부호에서 edge-effect를 감소시키기 위한 인터리버

이병길,배상재,정건현,주언경,Lee, Byeong-Gil,Bae, Sang-Jae,Jeong, Geon-Hyeon,Ju, Eon-Gyeong 대한전자공학회 2002 전자공학회논문지TC (Telecommunications) Vol.39 No.4

In the next generation mobile communications, powerful channel coding is essential in order to obtain high quality multimedia services. Turbo code can achieve good error performance by iterative decoding, but more iterations result in additional computational complexity and delay. Thus, a method to reduce the number of iterations without additional performance degradation is needed. Turbo code with CRC is known to be the most efficient method to reduce the number of iterations. In this scheme, the performance may be degraded by the edge-effect like the conventional turbo code without CRC. In this paper, a method to eliminate the edge-effect is proposed by adopting D-parameter to the conventional s-random interleaver. As results of simulation, the edge-effect of the turbo code with CRC is shown to be successfully eliminated by using the new interleaver designed with D-parameter.

SE프로세스를 통한 객체지향 실시간시스템 개발 방법론의 개선에 관한 연구

이병길,이재천,Lee, Byoung Gil,Lee, Jae Chon 한국시스템엔지니어링학회 2006 시스템엔지니어링학술지 Vol.2 No.2

In modern systems technology, increasingly more systems are anticipated to operate in real-time environment. These systems are usually complex to implement since it is not easy to satisfy the real-time requirement for both hardware and software components simultaneously. In this paper, we first review an object-oriented development process that was proposed earlier for software-intensive real-time system using the Unified Modeling Language (UML). We then study how to improve the problems that the UML approach might have. Applying the systems engineering(SE) process yields useful results which include : 1) an improved requirements management over the whole system life-cycle ; 2) a detailed scenario on how to carry out the SE process ; and 3) a conversion process from the text-based requirements to the UML-based graphic ones.

기능 모델의 효과적인 활용을 통한 역공학 프로세스의 개선에 관한 연구

이병길,이재천,Lee, Byoung-Gil,Lee, Jae-Chon 한국군사과학기술학회 2010 한국군사과학기술학회지 Vol.13 No.2

The necessity of the new system development arises in both defence and commercial systems industry either when a breakthrough in technology needs to be realized in the form of a brand-new system or when the existing product already in operation needs to be upgraded to satisfy the increasing stakeholder's requirements. In the latter case, it is not rare that specific system technical specifications on the existing products are not available. The purpose of this study is to investigate how to handle the difficulty when an upgraded system is required to be developed based on the existing product whose detailed technical specifications cannot be obtained. A step-by-step process is described based on the reverse engineering of the existing product. As a result, a logical system model is obtained for the product. The process developed is further enhanced and evaluated by the computer-aided system engineering tool. The resulting logical system model should be helpful in the next phase of the new product development.

점사상 밀도 분석을 위한 L-지표의 적용

이병길,Lee, Byoung-Kil 한국공간정보학회 2008 한국공간정보학회지 Vol.16 No.2

지도좌표를 가진 정보의 통계적 분석은 GIS 중요기능 중 하나로 인정되고 있다. 그 중 가장 기본적인 분석의 하나로 점사상에 대한 밀도분석이 이루어지고 있다. 밀도분석은 일반적으로 라스터 분석의 일부로 간주되고 있으며, 적합한 밀도분석을 위해서는 kernel 반경으로 알려진 검색반경의 결정이 중요한 것으로 알려져 있다. 본 연구에서는 기존 연구 결과에서 검색반경 설정에 유용한 것으로 알려진 L-지표를 이용하여, 비즈니스 GIS 분야에 축적된 점사상의 밀도 분석에 적합한 반경을 추정하고, 추정된 결과를 기반으로 점사상의 특성에 따른 L-지표의 거동을 고찰하였다. 연구결과 점사상이 대상지역의 일부 지역에서 크게 밀집되는 경우에는 L-지표가 대상지역의 크기와 무관하게 일정한 반경에서 극대값을 보이기 때문에 L-지표를 이용하여 검색반경을 설정하는 것이 유용함을 알 수 있었다. 반면, 점사상이 대상지역에 고루 분포하는 경우에는 L-지표의 극대값이 나타나는 반경이 대상지역의 크기에 따라 영향을 받기 때문에 L-지표를 이용하여 검색반경을 설정하는 것이 적합하지 않음을 알 수 있었다. 따라서 L-지표를 이용한 점사상 밀도의 검색반경 설정에는 점사상의 분포특성이 고려되어야 함을 알 수 있었다.

하모니서치 알고리즘을 이용한 반도체 공정의 최적버퍼 크기 결정

이병길,변민석,김여진,이종환,Lee, Byeong-Gil,Byun, Minseok,Kim, Yeojin,Lee, Jonghwan 한국반도체디스플레이기술학회 2020 반도체디스플레이기술학회지 Vol.19 No.4

In the production process, the buffer acts as a buffer to alleviate some of the problems such as delays in delivery and process control failures in unexpected situations. Determining the optimal buffer size can contribute to system performance, such as increased output and resource utilization. However, there are difficulties in allocating the optimal buffer due to the complexity of the process or the increase in the number of variables. Therefore, the purpose of this research is proposing an optimal buffer allocation that maximizes throughput. First step is to design the production process to carry out the research. The second step is to maximize the throughput through the harmony search algorithm and to find the buffer capacity that minimizes the lead time. To verify the efficiency, comparing the ratio of the total increase in throughput to the total increase in buffer capacity.

SE프로세스 기반 실시간 시스템 개발에 관한 연구

이병길,이재천,Lee, Byeong-Gil,Lee, Jae-Cheon 한국시스템엔지니어링협회 2005 시스템엔지니어링워크숍 Vol.6 No.-

철도안전정보지원시스템 요구사항 개발을 위한 엔터프라이즈 아키텍처 활용 사례

이병길,이재천,장재덕,김찬묵,김태현,조연옥,홍선호,최요철,Lee, Byeong-Gil,Lee, Jae-Cheon,Jang, Jae-Deok,Kim, Chan-Muk,Kim, Tae-Hyeon,Jo, Yeon-Ok,Hong, Seon-Ho,Choe, Yo-Cheol 한국시스템엔지니어링협회 2006 시스템엔지니어링워크숍 Vol.7 No.-

삶의 공간 세우기 20년

이병길,Lee, Byeong-Gil 대한건축사협회 2007 건축사 Vol.2007 No.6

이동통신 시스템을 위한 소스코더와 결합된 채널코딩방법에 의한 영상전송

이병길,박판종,조현욱,박길흠,Lee, Byung-Gil,Park, Pan-Jong,Cho, Hyun-Wook,Park, Gil-houm 대한전자공학회 2000 전자공학회논문지TC (Telecommunications) Vol.37 No.1

In this paper, we present the efficient image transmission system using designed source-channel combined coder in W-CDMA mobile communication system. In proposed schemes, we decompose the wavelet transformed hierarchical band-images into some types of different size blocks which have different properties in error sensitivity. The RS(Reed-Solomon) coder with different coding rate is used for each decomposed source blocks which has different importance. In addition, we combine retransmitted error frames in Truncated Hybrid Type I ARQ. The proposed algorithm shows efficient image transmission methods because it is not much degraded in PSNR compared with the existing not combined source-channel coder in erroneous wireless channel.

순수 유두 갑상선암과 소포 변이 유두 갑상선암: 임상병리학적 특성 비교 연구

이병길,윤현조,정성후,Byoung Kil Lee,M.D.,Hyun Jo Youn,M.D. and Sung Hoo Jung,M.D. 대한갑상선-내분비외과학회 2009 The Koreran journal of Endocrine Surgery Vol.9 No.1

Purpose: Pure papillary thyroid carcinoma (PPTC) and the follicular variant of papillary thyroid carcinoma (FVPTC) are the most common subtypes of papillary thyroid carcinoma (PTC). The aim of this study was to investigate if there are any differences in clinicopathological features of these two subgroups. Methods: We performed a retrospective chart review of patients who were treated for PPTC and FVPTC between September 2003 and April 2008. Four hundred fifty patients were shown to have PPTC (91.8%) and forty (8.2%) had FVPTC after a histologic review. The two groups were compared in terms of the clinicopathologic features and the results of preoperative ultrasonography (USG), the fine needle aspiration cytology (FNAC), the frozen section biopsy and the surgical treatment. Results: The tumor size was significantly larger in the FVPTC group than in the PPTC group (1.47 cm versus 1.08 cm, respectively P=0.024). However, both groups had similar clinicopathologic features in terms of age, gender, capsular invasion, multifocality, lymph node metastasis, the MACIS score and the TNM stage. Further, the operative method did not differ between the two groups. The sensitivities of USG and frozen section biopsy for diagnosing FVPTC were significantly lower than those for PPTC (53.85% versus 72.95%, respectively, P=0.045, 81.58% versus 97.25%, respectively, P=0.049). Conclusion: The FVPTC group presented with a larger tumor size, and the clinicopathologic features of the FVPTC group did not significantly differ from those of the PPTC group. Although further studies with longer follow-up are required, these results suggest that the patients in both groups should be treated identically. (Korean J Endocrine Surg 2009;9:19-23)