자가 슬괵건을 이용한 전방 십자인대 재건술시 경골측 골 터널내 고정의 의의 (이차관절경 검사의 평가)

김영창,서승석,정경칠,곽희철,김윤준,김진석,Kim, Young-Chang,Seo, Seung-Suk,Jung, Kyung-Chil,Gwak, Hey-Chul,Kim, Yoon-Jun,Kim, Jin-Seok 대한관절경학회 2006 대한관절경학회지 Vol.10 No.2

Purpose: The purpose of this study is to evaluate the effects of intratunnel fixation in the tibial side on the arthroscopic ACL reconstruction with quadruple hamstring tendon at the second look arthroscopy. Materials and Method: From Dec 1999 to May 2005, we arthroscopically reexamined 32 cases who had been done arthroscopic ACL reconstruction with quadruple hamstring tendons. Hamstring tendons of all cases were fixed at femoral side with RigidfixTM. At the tibial side hamstring tendons were fixed only Post-tie (Group I) or Post-tie combined with IntrafixTM (Group II). At the time of second look arthroscopy mean age of cases was 30 years and mean duration for second look arthroscopy was 21.3 months. We analyzed the results with IKDC score, KT-1000 arthrometer under anesthesia, Telos stress radiography, tibial tunnel widening on the radiography and second look arthroscopic findings. Results: Group II had more superior than group I at side to side differences with KT-1000 and Telos stress radiograph, IKDC score, but the differences were insignificant. At arthroscopic evaluation, Group ll also had more superior than group I at graft tension and graft appearance, graft synovialization, but the differences were insignificant. Tibial tunnel widening in the knee AP radiograph was 2.3 mm in Group I and 1.7 mm in Group II and the difference was significant. (P=0.042) Conclusions: Additional procedure of tibial intratunnel fixation in arthroscopic ACL reconstruction with autogenous hamstring tendon significantly prohibited from tibial tunnel widening but clinical results, radiologic joint stability, findings in second look arthroscopy were insignificantly different. We concluded that Post-tie itself induced satisfactory clinical results, joint stability and graft maturation and that tibial tunnel widening did not affect the results.

대용량 이동객체의 위치정보 관리를 위한 S-GRID를 이용한 분산 그리드 기법

김영창,김영진,장재우,Kim, Young-Chang,Kim, Young-Jin,Chang, Jae-Woo 한국공간정보시스템학회 2008 한국공간정보시스템학회 논문지 Vol.10 No.4

Recently, advances in mobile devices and wireless communication technologies require research on various location-based services. As a result, many studies on processing k-nearest neighbor query, which is most im portant one in location-based services, have been done. Most of existing studies use pre-computation technique to improve retrieval performance by computing network distance between POIs and nodes beforehand in spatial networks. However, they have a drawback that they can not deal with effectively the update of POIs to be searched. In this paper, we propose a distributed grid scheme using S-GRID to overcome the disadvantage of the existing work as well as to manage the location information of a large number of moving objects in efficient way. In addition, we describe a k-nearest neighbor(k-NN) query processing algorithm for the proposed distributed grid scheme. Finally, we show the efficiency of our distributed grid scheme by making a performance comparison between the k-NN query processing algorithm of our scheme and that of S-GRID. 최근 모바일 기기 및 무선 통신의 발달로 인하여 다양한 위치 기반 서비스에 대한 연구가 증대되고 있으며, 이러한 위치 기반 서비스의 대표적 질의인 k-최근접 질의를 효율적으로 처리하기 위한 연구가 활발히 수행되어 왔다. 기존 연구들은 질의 처리 성능의 향상을 위해, 공간 네트워크 상의 POI와 노드 사이의 거리를 미리 계산하는 pre-computation 기법을 사용한다. 그러나 이러한 pre-computation 기법들은 검색 대상이 되는 POI의 변경을 효과적으로 처리하지 못하는 단점을 갖는다. 본 논문에서는 기존 pre-computation 기법들의 단점을 극복하고, 대용량 이동객체의 위치정보를 효율적으로 관리하기 위하여 S-GRID를 이용한 분산 그리드 기법을 제안한다. 아울러 제안하는 분산 그리드 기법을 위한 k-최근접 질의 처리 알고리즘을 제시한다. 마지막으로, S-GRID 및 분산 그리드 기법의 k-최근접 질의처리 알고리즘의 성능 평가를 통해, 제안하는 기법의 우수성을 입증한다.

분산 그리드 기법을 위한 연속 k-최근접 질의처리 알고리즘

김영창,장재우,Kim, Young-Chang,Chang, Jae-Woo 한국공간정보시스템학회 2009 한국공간정보시스템학회 논문지 Vol.11 No.3

최근 GPS 및 무선 이동 컴퓨팅 기술의 발달로 인해, 텔레매틱스(telematics) 및 위치기반 서비스(LBS) 응용이 활발하게 연구되고 있다. 이러한 위치 기반 서비스 응용에서는 이동객체의 위치 정보가 시간의 흐름에 따라 계속적으로 변하기 때문에, 이를 위한 빈번한 업데이트 연산은 시스템에 많은 부하를 가중시키며 이로 인해 검색 성능의 저하를 초래한다. 이를 해결하기 위해 공간 네트워크에서 대용량 이동객체의 위치정보를 분산 처리하기 위한 DS-GRID(distributed S-GRID) 및 이를 위한 k-최근접 질의처리 알 고리즘이 제안되었다[1]. 그러나 k-최근접 질의처리 기법은 질의점 및 이동객체의 위치가 변경되면 그 결과 가 유효하지 않기 때문에, 연속 k-최근접(CKNN:continuous k-nearest neighbor) 질의처리 알고리즘의 연구가 필요하다. 본 연구에서는 DS-GRID를 위한 MCE-CKNN 알고리즘 및 MBP-CKNN 알고리즘을 제안한다. MCE-CKNN 알고리즘은 주어진 경로를 셀 단위로 분할하여 각 셀에서 질의 처리를 병렬적으로 수행하여 검색 성능을 향상시킨다. 아울러 MBP-CKNN 알고리즘은 그리드 셀의 각 경계점에서 가까운 POI를 미리 저장하여 인접셀 탐색 횟수를 줄임으로써 검색 성능을 향상시킨다. 마지막으로, 제안하는 알고리즘의 성능 분석을 통해, 기존 알고리즘보다 15-53% 검색 성능이 우수함을 나타내었다. Recently, due to the advanced technologies of mobile devices and wireless communication, there are many studies on telematics and LBS(location-based service) applications. because moving objects usually move on spatial networks, their locations are updated frequently, leading to the degradation of retrieval performance. To manage the frequent updates of moving objects' locations in an efficient way, a new distributed grid scheme, called DS-GRID (distributed S-GRID), and k-NN(k-nearest neighbor) query processing algorithm was proposed[1]. However, the result of k-NN query processing technique may be invalidated as the location of query and moving objects are changed. Therefore, it is necessary to study on continuous k-NN query processing algorithm. In this paper, we propose both MCE-CKNN and MBP(Monitoring in Border Point)-CKNN algorithmss are S-GRID. The MCE-CKNN algorithm splits a query route into sub-routes based on cell and seproves retrieval performance by processing query in parallel way by. In addition, the MBP-CKNN algorithm stores POIs from the border points of each grid cells and seproves retrieval performance by decreasing the number of accesses to the adjacent cells. Finally, it is shown from the performance analysis that our CKNN algorithms achieves 15-53% better retrieval performance than the Kolahdouzan's algorithm.

인삼 종자의 개갑률 향상을 위한 적정 수확시기 및 GA₃ 처리 효과

김영창,김영배,박홍우,방경환,김장욱,조익현,김기홍,송범헌,김동휘,Kim, Young Chang,Kim, Young Bae,Park, Hong Woo,Bang, Kyong Hwan,Kim, Jang Uk,Jo, Ick Hyun,Kim, Kee Hong,Song, Beom Heon,Kim, Dong Hwi 한국약용작물학회 2014 한국약용작물학회지 Vol.22 No.6

This study was performed to identify optimal harvesting time of ginseng seeds and to examine the effect of $GA_3$ treatment for improvement of seed stratification rate. Ginseng seeds harvested from Land race, Chunpoong and Yunpoong cultivar in July 20 were tested for stratification rate. It was shown that stratification rates of land race, Yunpoong and Chunpoong cultivar were 94.1%, 93.1%, and 82.6%, respectively. Seeds of Chunpoong cultivar harvested 10-15 days later showed a comparable stratification rate to that of Land race, indicating that late harvest of Chunpoong seeds is beneficial for the increase of stratification rate. The higher stratification rate was found in mature seeds (92.3%) than immature seeds (37.8%), both of which were harvested in July 20. Stratification rate of mature seeds harvested in July 15 was 87.5%, demonstrating optimal harvesting time of ginseng seeds with higher stratification rate is after mid-July. An exponential growth of endosperms of ginseng seeds was observed from early June to mid-June and then slow growth was observed. There was no obvious growth of embryos from fertilization to mid-August. After the this time, embryos quickly grew until late October. Thus, appropriate stratification control is essential during the period (from early September to late October) in order to optimize embryo growth and development. While no increase of stratification rate was observed in seeds treated with 50 ppm of $GA_3$, significant increases were observed in seeds treated with 100 ppm of $GA_3$. At this concentration of $GA_3$, the stratification rate of Land race, Chunpoong and Yunpoong cultivar was 95.0%, 95.3%, and 96.5%, respectively.

의과대학 학생 임상실습을 위한 교육병원의 역할 제고 방안

김영창,Kim, Young Chang 연세대학교 의과대학 2015 의학교육논단 Vol.17 No.1

The mission of the modern medical school includes education, research, and patient care. The clinical clerkship is an important part of the core curriculum, and hospital facilities are needed for the clinical clerkship. However, unfortunately, education has moved to the periphery during the past several decades because of the dominance of research and patient care. This may lead to obstacles in the education of future physicians in the long term. To promote their education mission, teaching hospitals need to recognize and share the importance of this mission. In addition to the certification of teaching hospitals, a new paradigm for teaching hospitals should be introduced to produce a high quality clinical clerkship and postgraduate medical education. The relevant government departments need to allocate and expand financial support to medical schools and teaching hospitals, and to unify supervision of basic and postgraduate medical education.

도로 네트워크에서 이동 객체를 위한 시공간 유사 궤적 검색 알고리즘

김영창,라빈드라 비스타,장재우,Kim, Young-Chang,Vista, Rabindra,Chang, Jae-Woo 한국공간정보학회 2007 한국공간정보시스템학회 논문지 Vol.9 No.1

모바일 환경의 대중화와 이를 위한 기반 기술의 발전으로 인하여 이동 객체들을 효과적으로 표현하고 분석하는 것이 중요한 문제로 대두되고 있다. 이러한 환경에서 이동 객체 궤적의 유사성 검색은 궤적에 대한 데이터 마이닝의 일부분으로 중요한 연구 분야중의 하나이다. 본 논문에서는 도로 네트워크상의 이동 객체 궤적을 위한 시공간 유사 궤적 검색 알고리즘을 제안한다. 이를 위하여 도로 네트워크상에서 두 이동 객체 궤적 사이의 시공간 거리를 정의하고, 이를 기반으로 궤적 사이의 시공간 유사도 측정 방법을 제안한다. 유사 궤적 알고리즘은 효율적인 검색을 위하여 시그니쳐 파일 기법을 이용하여 궤적을 검색한다. 마지막으로, 본 논문에서 제안하는 시공간 유사 궤적 검색 알고리즘을 구현하고, 성능 분석을 통해 제안하는 알고리즘의 효율성을 입증한다. Advances in mobile techknowledges and supporting techniques require an effective representation and analysis of moving objects. Similarity search of moving object trajectories is an active research area in data mining. In this paper, we propose a trajectory search algorithm for spatio-temporal similarity of moving objects on road network. For this, we define spatio-temporal distance between two trajectories of moving objects on road networks, and propose a new method to measure spatio-temporal similarity based on the real road network distance. In addition, we propose a similar trajectory search algorithm that retrieves spatio-temporal similar trajectories in the road network. The algorithm uses a signature file in order to retrieve candidate trajectories efficiently. Finally, we provide performance analysis to show the efficiency of the proposed algorithm.

Lactobacillus casei Phage J1 Genome의 Cohesive End Site 염기배열

김영창,성학모,강현삼,Kim, Young-Chang,Seong, Hark-Mo,Gang, Hyeon-Sam 한국미생물학회 1994 미생물학회지 Vol.32 No.3

The nucleotide sequence of the cohesive end site (cos) of Lactobacillus casei phage J1 genome was determined. Comparison between the nucleotide sequences of the circular cos and the left end of the linear J1 DNA showed that the nicking sites of the terminase were as follows: 5'- GGTCGGCC$\downarrow$ -3' 3'- $\uparrow$CCAGCCGG -5' The cohesive single-stranded ends of J1 were found to be 3'-protruding and composed of 8 nucleotides. The mol% G + C of the cohesive ends was 87.5. The cos site shows dyad symmetry from -33 to + 25 bp if the 5' terminal nucleotide of the left end of the linear J1 DNA is numbered +1. No homology was found among the cos sites of phages reported so far.

만성 족관절 불안정성에서 하신전 지지대 및 원위 비골 골막을 이용한 해부학적 재건술

김영창,곽희철,정경칠,최장석,서진혁,Kim, Young-Chang,Gwak, Heui-Chul,Jung, Kyung-Chil,Choi, Jang-Seok,Seo, Jin-Hyuk 대한족부족관절학회 2007 대한족부족관절학회지 Vol.11 No.2

Purpose: To evaluate the results of surgical reconstruction of lateral capsule-ligament complex with reinforcement by periosteal flap of distal fibula and inferior extensor retinaculum for chronic lateral ankle instability. Materials and Methods: From April 2003 to August 2006, 62 patients with chronic lateral ankle instability were operated. There were 38 males and 24 females with a mean age of 39.6 years (range, $18{\sim}61$ years). Mean follow-up period was 32 months (range, $10{\sim}48$ months). All patients were checked with preoperative ankle anteroposterior and lateral view, stress anterior drawer and varus test using Telos device. The clinical results were graded according to the VAS and AOFAS scale. Results: VAS score improved from preoperative 8.2 points to 3.1 points. There were 38 patients who were excellent (above 90 points), 18 who were good (between 76 and 90 points), 5 who were fair (between 60 and 75 points), and 1 who was poor (below 60 points) according to the AOFAS ankle and hindfoot scale. The excellent and good results amounted to 90.3%. Conclusion: Surgical reconstruction of lateral capsule-ligament complex with reinforcement by periosteal flap of distal fibula and inferior extensor retinaculum is believed to be a effective method for chronic lateral ankle instability.

족무지 종자골에 발생한 무혈성 골괴사증(3예 보고)

김영창,곽희철,김정한,문상원,Kim, Young-Chang,Gwak, Heui-Chul,Kim, Jung-Han,Moon, Sang-Won 대한족부족관절학회 2009 대한족부족관절학회지 Vol.13 No.2

Although avascular necrosis of the hallucal sesamoid has not been frequently addressed in the literature, it should be considered in the differential diagnosis of persistent forefoot pain. We experienced 3 cases of avascular necrosis of the hallucal sesamoid with sclerosis of the sesamoid bone on radiograghs and computed tomograghy images. T1 and T2-weighted MRI images in 2 patients showed low signal intensity in the sesamoid bone, which suggested osteonecrosis and confirmed by histology. We report 3 cases of avascular necrosis of sesamoid with a review of the literature.

우리나라 인삼 육종의 주요 성과와 전망

방경환(Kyong-Hwan Bang),김영창(Young-Chang Kim),이정우(Jung-Woo Lee),조익현(Ick-Hyun Cho),홍지은(Chi-Eun Hong),현동윤(Dong-Yun Hyun),김장욱(Jang-Uk Kim) 한국육종학회 2020 한국육종학회지 Vol.52 No.S

Artificial selection of ginseng has been practiced since Hwangsook (with yellow pericarp and a green stalk, and was developed from a landrace parent) and Cheonggyeong (with red pericarp) were selected as breeding lines in 1926. Systematic research into ginseng breeding, however, started in earnest in the 1960s when the Central Research Institute of Monopoly and Technology (CRIMT) was established, and the Korean Ginseng Experiment Station was organized under the CRIMT. Research into variant characteristics, resource collections, and genetic evaluations began around this time. With the establishment of the Korean Ginseng Institute in the 1970s, studies involving pedigree selection, cataloguing of agricultural traits of genetic resources, generation shortening by tissue culture, and heritability assessments were conducted. In the 1980s, regional adaptation tests were carried out on breeding lines, focusing on ginseng-producing districts. In the 1990s, research was performed on seed multiplication for variety diffusion, effective components and processing quality, and cross breeding. Foreign ginsengs were introduced for interspecies hybridization, and studies were conducted using genetic engineering techniques. Since the 2000s, applications have been made to patent different ginseng cultivars. Currently, 32 cultivars are registered at the Korea Seed & Variety Service. Future goals for ginseng breeding include developing climate change- and disaster-resistant, consumer-oriented, high-performance cultivars. Therefore, it is necessary to develop technologies for distributing new cultivars by collecting and evaluating genetic resources, and cross breeding and performing mass propagation using these resources.