Link Adaptation with SNR Offset for Wireless LAN Systems

김찬홍,정교원,고경준,이정우,Kim, Chan-Hong,Jeong, Kyo-Won,Ko, Kyeong-Jun,Lee, Jung-Woo The Korean Institute of Communications and Informa 2011 韓國通信學會論文誌 Vol.36 No.10A

Link Adaptation should select the best modulation and coding scheme (MCS) which gives the highest throughput as channel conditions vary. Several link adaptation algorithms for wireless local area network (WLAN) have been proposed but for the future WLAN systems such as 802.11n system, these algorithms do not guarantee the best performance. In this paper, we propose a new link adaptation algorithm in which an MCS level is chosen by the received SNR plus the offset value obtained from the transmission results. The performance of proposed algorithm is simulated by an IEEE 802.11n system. From the analysis, we conclude the proposed algorithm performs better than the well-known link adaptation algorithms such as auto rate fallback and general SNR-based techniques. Particularly, the proposed algorithm improves throughput when the packet error ratio (PER) is constrained for fast fading channels. 링크 적응 기법은 변하는 채널 조건에 맞는 최적의 MCS 레벨을 선택한다. 무선 LAN 시스템을 위한 다양한 링크 적응 알고리즘이 제안되었으나 802.11n과 같은 최근의 시스템에서 최적의 성능을 보장하지는 않는다. 본 논문에서는 수신 SNR과 전송 결과에 따라 얻어지는 오프셋 값을 이용한 새로운 링크 적응 알고리즘을 제안한다. 802.11n 시스템에서 모의실험을 하여 제안된 알고리즘과 잘 알려져 있는 ARF 및 일반적인 SNR기반 알고리즘과 그 성능을 비교해본다. 제안된 알고리즘은 PER에 제한이 있는 경우 시변채널에서 더 좋은 성능을 보인다.

Earth Mover's Distance 기반 M-트리의 성능 분석

이원조 ( Won-jo Lee ),하성대 ( Sung-dae Ha ),정교성 ( Kyo-sung Jung ),장민희 ( Min-hee Jang ),김상욱 ( Sang-wook Kim ) 한국정보처리학회 2011 한국정보처리학회 학술대회논문집 Vol.18 No.2

Earth mover's distance(EMD)는 내용 기반 데이터 검색을 위한 거리 함수로서 정확도가 매우 높은 검색 결과를 가져오지만, 계산 복잡도가 높아 대용량 데이터베이스에서 사용하기 어렵다. 이러한 문제를 해결하기 위한 방법으로 다차원 인덱스인 M-트리를 사용하여 데이터 비교 횟수를 크게 줄일 수 있다. 그러나 고차원의 데이터에 인덱스를 사용하면 차원의 저주 문제로 인해 검색 성능이 크게 저하 될 수 있다. 본 논문에서는 이러한 문제를 정량적으로 검증하기 위하여 고차원 데이터를 대상으로 EMD 기반 M-트리를 구축한 후 다양한 실험을 수행한다. 실험 결과, 고차원 데이터에서도 차원의 저주는 일어나지 않는 것으로 나타났다. 이러한 공헌은 EMD의 검색 성능 개선을 위한 정책을 고안하는데, 중요한 실마리를 제공할 수 있을 것이다.

국내ㆍ외 전자서명 및 인증제도 동향 분석

이대기(Dai-ki Lee),김희선(Hee-sun Kim),조영섭(Yeong-sub Cho),진승헌(Seung-hun Jin),정교일(Kyo-il Jung),조현숙(Hyun-sook Cho) 한국정보보호학회 2001 情報保護學會誌 Vol.11 No.4

개인건강정보의 2차이용 보호에 관한 국내외 법안 연구

박한나(Han-na Park),정부금(Boo-Geum Jung),이동훈(Dong-Hoon Lee),정교일(Kyo-il Chung) 한국정보보호학회 2010 정보보호학회논문지 Vol.20 No.6

의료서비스와 IT 기술간의 융합으로 환자 개인의 건강정보가 전자의무기록(EHR)의 보급과 함께 빠르게 전자화되고 있다. 이와 함께 유헬스사회에 접어들면서 전자화 된 환자의 건강기록들을 진료 이외의 공중보건 및 의학 분야의 연구, 의료서비스 향상을 위해 사용하고자 하는 2차이용의 요구가 증가하고 있다. 개인건강정보의 2차이용으로 의학분야의 발전은 매우 유익한 일이지만 부주의하게 개인의 건강정보를 이용하는 경우 환자 개인의 프라이버시 손상이 발생, 더불어 2차이용을 통한 연구나 서비스 발전에도 제한이 발생할 수 있다. 하지만 아직 개인건강정보를 이용한 2차적 이용에 대해 체계적인 연구나 논의가 없는 것이 현실이다. 따라서 본 논문에서는 개인건강정보의 2차이용과 관련하여 국내외의 법안들을 살펴보고 이를 비교 분석하여 앞으로 개인의 프라이버시를 존중하고 더불어 의료분야 서비스의 발전을 도모할 수 있는 방향을 제시하고자 한다. Through the convergence of medical services and the IT technique, the patient’s personal health information computerization has been rapidly spread with propagation of electronic medical record(EHR). In addition, by entering u-health, the demand of the secondary use for public health, medical research, and medical service using electronic patient health care records are increasing. The personal health information secondary uses for the development of academic medical area and service, are very good thing. But, carelessly to use personal health information, the patient privacy would be damaged. However, there are not yet systematic studies about secondary use of personal health information. Therefore, in this paper, we analyze the difference of the internal and external bill for personal medical data secondary use and propose the direction of the medical service development and preservation of the individual's privacy.

표면피복 양생재의 사용 여부에 따른 콘크리트의 균열양상 비교

이정교(Lee, Jung Kyo),조만기(Jo, Man Ki),박용준(Park, Yong Jun),이제현(Lee, Jea Hyeon),한민철(Han, Min Cheol),한천구(Han, Cheon Goo) 한국콘크리트학회 2016 한국콘크리트학회 학술대회 논문집 Vol.28 No.1

사인커뮤니케이션의 예술성 그리고 공익성

이정교(Lee Jung-kyo) 한국옥외광고학회 2004 OOH광고학연구 Vol.1 No.1

오늘날 사인커뮤니케이션은 정보로서의 본래의 기능을 이행해야하고 문화적 배경이 고려된 매체방법으로 사용되어야 하며, 동시에 도시의 환경관계까지도 고려해야한다. 최근 사인커뮤니케이션은 예술성과 공익성 측면에서 각양각색의 예술적 즐거움을 위한 표현매체로서 연출되지 위해 다양하고, 더 높은 수준과 더 큰 의미가 포함되는 이들의 트렌드들을 반영하기 시작한다. 그러므로 본 연구는 사인커뮤니케이션디자인의 예술성을 위한 디자인 적용요소(그래픽, 색채, 레이아웃, 형태, 구조, 조명 등)를 영역화하는데 있으며 그와 더불어 사회적 공익성으로서 환경과 조화되는 명확한 방법의 사인커뮤니케이션을 연구하는데 목적이 있다. 본 연구를 통해 사인커뮤니케이션디자인의 예술성과 공익성을 위한 구체화된 디자인 조형 기본요소를 제안하고 미래의 나아갈 방향을 제시함로써 사인커뮤니케이션디자인 활성화에 기여하고자 한다. Nowdays sign-communications must consider the environmental concerns for urban cities as well as perform the natural roles such as information media for the cultural background. It is now an early stage that sign-communications begin to reflect these trends as they are used as a production space for the enjoyment of art. They become diversified, bigger, and get upgraded in their consideration of form-giving and public good. Therefore, the research aims to identify the design factors for general applications (graphic, color, layout, form, structure, light etc.) in form-giving of sign-communication design and suggest a way of a specific sign-communication design harmonizing with the environment for a social public good. We hope that the study on the sign-communication design will become more activated using the proposed approach pursuing a form-giving and public good based on the design factors identified.

2015 개정교육과정에 따른 초등학교 소프트웨어 교육에서의 평가의 현황과 방향

정정교(Jung, Jung Kyo),이원석(Lee, Wonsuk) 질적연구학회 2018 질적연구 Vol.19 No.1

Purpose: The main purpose of this study was to understand evaluation for software education in elementary school. Methods: This study use Convergent Parallel Design of mixed method. Quantitative and qualitative data gathered in elementary software research schools were analyzed to find out present state and problem of evaluation. Results: The characteristics of the software education evaluation identified by the quantitative and qualitative data are as follows: Evaluation is primarily performed on performance assessment. Formative evaluation is actively utilized. Students’ participation in evaluation is emphasized. Informal evaluation is mainly performed. There is a difference in teachers’ perception of the evaluation methods. Conclusion: Evaluation in software education should be performed through performance assessment, formative evaluation, active participation of students. In addition, the understanding of computational thinking and the development of concrete evaluation methods of computational thinking.

안전한 임플란트 식립을 위한 하악골 내측면의 CBCT를 이용한 해부학적 연구

이정교(Jung-Kyo Lee),김여갑(Yeo-Gab Kim) 대한구강악안면외과학회 2011 대한구강악안면외과학회지 Vol.37 No.1

Introduction: This study examined the anatomical morphology of the medial surface of the posterior mandible using 3-dimensional cone-beam computed tomography (CT) images to reduce the number of complications related to dental implant placement. Materials and Methods: Fifty patients were enrolled in this study with an average age (±standard deviation) of 44.28 (±13.05). On the coronal views cone-beam CT of the first molars, the distance between the top of the canal and alveolar crest vertical distance (VD), the distance between the upper-most point of the canal and the point perpendicular to the lingual cortical margin of the mandible lingual distance (LD), the location of the starting point of VD for reducing from the vertical reference line (VD point), and the inclination of the mandibular medial surface (lingual inclination) were measured, and a statistical evaluation was performed using SPSS for Windows version 15.0. Results: The mean VD0 was 16.91±2.47 mm and VDx decreased with increasing x value. The mean LD was 5.27±1.36 mm. The VD began to decrease at the mean location of 6.12±0.96 mm from the vertical reference line. The mean lingual inclination was 1.52±0.72 . Conclusion: These results will assist in the accurate placement of dental implants and the reduction of complications, particularly in the case of preoperative implant planning using only 2-dimensional imaging methods. (ex. panoramic radiography)

무향팬테스터를 이용한 냉장고용 팬 성능/소음 측정

정정교(Jeoung jeoung-kyo),이준화(Lee jun-hwa),주재만(Joo Jae-man),강정훈(Kang jung-hun) 한국소음진동공학회 2004 한국소음진동공학회 학술대회논문집 Vol.2004 No.11

전측두엽 절제술시 해마체 절제 범위와 경련 예후

이완수,이정교,이상암,강중구,고태성,Lee, Wan Su,Lee, Jung Kyo,Lee, Sang Am,Kang, Jung Ku,Ko, Tae Seong 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.12

Objective : Little consensus exists concerning which temporal lobe structures need to be resected or how much resection should be done during hippocampal resection. The purpose of this study is to identify whether the extent of hippocampal resection influences seizure after anterior temporal lobectomy. Materials and Methods : The extent of hippocampal resection was assessed in 96 patients who underwent temporal lobectomy for medically intractable complex partial seizures originating from a unilateral seizure focus in the anteromesial temporal lobe. Patients who had structural lesion were excluded from the study. Postoperative magnetic resonance imaging in the coronal and saggital planes were used to quantify the extent of the hippocampal and lateral cortical resection. The patients were divided into two groups. Patients who underwent hippocampal resection to the level of the cerebral peduncle were included in the partial resection group, and those who had resection to the level of the colliculus were assigned to total resection group. Seizure outcomes were defined according to the Engel classification and compared between the two groups. Neuropsychologic outcomes in the selected cases were reviewed. Results : The over-all seizure-free outcome(Engel classification 1) was accomplished in 75%(72/96) of the patients (mean duration of follow-up, 36.8 months). The total hippocampectomy group had a statistically superior seizure outcome than the partial hippocampectomy group(87.3% versus 58.5% seizure-free, p-value=0.001). Also, younger patients had a more favorable outcome. Other variables such as laterality, the extent of lateral cortical resection, age at onset and gender were not significant. The pre- and postoperative memory functions were evaluated in 24 patients. A worse postoperative memory outcome was associated with partial hippocampectomy. However this was not acceptable due to a former bias. Conclusion : The result of this study conforms that aggressive hippocampectomy resulted in a better seizure outcome.