혈관 부착 이식 비골에 발생한 피로골절

김형민,김윤수,이기행,정창훈,김준석,Kim, Hyoung-Min,Kim, Youn-Soo,Lee, Kee-Haeng,Jeong, Chang-Hoon,Kim, Jun-Seok 대한미세수술학회 2001 Archives of reconstructive microsurgery Vol.10 No.1

Purpose : The purpose of this study was to evaluate stress fracture of vascularized fibular grafts(VFG) by analyzing factors associated with stress fracture and the treatment results. Materials and Methods : From June 1985 to May 1998, 7 patients with stress fractures in the 38 patients with long bone defect who had vascularized fibular graft were evaluated with clinical and radiologic methods including grafted fibular length and hypertrophic index of de Boer. The average age of the patients was 35 years(range, $14{\sim}60$ years). The mean follow-up period was 20 months(range, $16{\sim}32$ months). Results: 7(18.4%) stress fractures occurred in 38 patients. Characteristics of the fractures were (1) all occurred at lower extremity of male patients treated with VFG for long bone defected caused by infected nonunion; (2) all occurred 10 months at the average(range, $4{\sim}17$ months) after VFG; and (3) the length and hypertrophic index of grafted fibula had no influence on the incidence of stress fracture. Union was obtained in 3 patients by conservative treatment. 4 patients obtained union by internal fixation; one at immediately onset of fracture; and three after failure of conservative treatment who had fracture around the knee joint. Conclusion : Stress fracture may occur during the first one year after vascularized fibular graft and more attention must be paid for prevention of it, especially in the cases of infected nonunion. Stress fracture around the knee joint was expected to lead to a good result of early union by operative treatment.

결측 공변량을 갖는 혼합회귀모형에서의 EM 알고리즘

김형민,함건희,서병태,Kim, Hyungmin,Ham, Geonhee,Seo, Byungtae 한국통계학회 2016 응용통계연구 Vol.29 No.7

혼합회귀모형은 반응 변수와 공변량 사이의 관계를 규명하는 유용한 통계적 모형으로 여러 분야에서 사용되어지고 있다. 하지만 실제로 혼합회귀모형을 이용하여 분석을 하는 과정에서 공변량이 결측값을 포함하는 문제는 흔하게 발생하며, 발생하는 결측의 유형 또한 다양하게 나타난다. 이러한 경우에 있어서 본 논문에서는 최대우도추정량을 구하기 위한 EM 알고리즘을 제안하고자 한다. 제안된 EM 알고리즘의 효용성을 모의실험을 통해 확인하였으며 또한 사례연구를 통해 제시된 방법이 어떻게 사용될수 있는지와 그 효용성을 함께 확인하였다. Finite mixtures of regression models provide an effective tool to explore a hidden functional relationship between a response variable and covariates. However, it is common in practice that data are not fully observed due to several reasons. In this paper, we derived an expectation-maximization (EM) algorithm to obtain the maximum likelihood estimator when some covariates are missing at random in the finite mixture of regression models. We conduct some simulation studies and we also provide some real data examples to show the validity of the derived EM algorithm.

내전 구축이 생긴 수부 무지 지간 공간의 재건술

김형민,송석환,김윤수,최문구,이기행,정창훈,정진호,Kim, Hyoung-Min,Song, Suk-Whan,Kim, Youn-Soo,Choi, Moon-Gu,Lee, Kee-Haeng,Jeong, Chang-Hoon,Jung, Jin-Ho 대한미세수술학회 2001 Archives of reconstructive microsurgery Vol.10 No.2

This study evaluated the results of reconstructions of thumb web space in the patients with adduction contracture of thumb. Between February 1990 and April 2000, 28 patients with thumb web space adduction contracture were treated with various reconstruction methods. We divided the patients according to the severity; mild$(41^{\circ}{\sim}80^{\circ})$, moderate$(21^{\circ}{\sim}40^{\circ})$, severe$(20^{\circ}less)$ contracture. The number of patients with mild contracture was 5, moderate; 12, severe; 11. We performed Z-plasty in 15, free flap in 8, local flap in 3, abdominal flap in 1 and scar release only in 1 case. The mean follow-up period was 5.7 years, ranged from 1.5 to 11.2 years. The results of web reconstruction were evaulated by thumb web space angle. There were excellent in 9, good in 16, fair in 3 cases. Z-plasty was performed in the 5 cases with mild contracture, and all the results were excellent. Especially, free flap was performed in the 6 cases with severe contracture, and all the results were good or excellent. in the reconstruction of thumb web space contracture, we recommend Z-plasty for a mild contracture, and free flap for large soft tissue defect created by release of a severe contracture.

혈관경 이식술을 이용한 거골의 외상성 무혈성 괴사의 치료 - 2례의 예비보고 -

김형민,정창훈,이기행,최문구,김윤수,고락현,Kim, Hyoung-Min,Jeong, Chang-Hoon,Lee, Kee-Haeng,Choi, Moon-Gu,Kim, Yoon-Soo,Ko, Lak-Hyun 대한미세수술학회 1999 Archives of reconstructive microsurgery Vol.8 No.1

Avascular necrosis is a significant late complication of talar neck fracture. However, treatment for early stage avascular necrosis has been not established. Two patients with post-traumatic avascular necrosis of talus treated with vascular pedicle graft using lateral tarsal artery were reviewed to determine the efficacy of procedure. The procedure involved grafting the lateral tarsal artery and vein into a hole made in the talus through a anterolateral approach. Follow-up was 12 and 24 months respectively. Two patients had significant pain relief, improved function, no worsening of their radiologic staging. The results are promising enough to recommend consideration of this procedure in early stages of avascular necrosis.

전방골간신경 증후군: 수술적으로 치료한 7예에 대한 임상적 고찰

김형민,정창훈,이상욱,노연태,박일중,Kim, Hyoung-Min,Jeong, Chang-Hoon,Lee, Sang-Uk,Roh, Youn-Tae,Park, Il-Jung 대한미세수술학회 2009 Archives of reconstructive microsurgery Vol.18 No.2

Purpose: The etiology and treatment strategy of the anterior interosseous nerve (AIN) syndrome are still controversial. Seven patients with the AIN syndrome who were treated by surgical exploration and neurolysis were reviewed at a mean of 35.9 months follow up period. Materials & Methods: There were six men and one woman. The mean age was 37.3 years, ranging from 26 to 59. No patient was related to trauma and associated neurological lesion. Surgical exploration was performed at 7.7 months after onset of paralysis. Results: All except one patients experienced pain around the elbow region before the onset of the palsy. On 7 patients, only the flexor pollicis longus was paralysed in 1, only the index flexor digitorum profundus in 2, and none had paralysis of the middle. The most common compression structures were fibrous bands within flexor digitorum sublimis arcade. However there was no demonstrable abnormality in three. Recovery was complete in all cases within 12 months after surgery. Conclusion: We recommended surgical exploration and neurolysis in patients who have shown no improvement after 6 months of conservative treatment. And careful preoperative examination is essential to avoid misdiagnosis and inappropriate surgery, especially in incomplete AIN syndrome.

광대역통합망에서의 비동기 구조를 이용한 신뢰성 있는 웹 서비스 제공방안

김형민,정의헌,김화성,Kim Hyoung-min,Jung Yeu-hun,Kim Hwa-sung 한국정보처리학회 2005 정보처리학회논문지 C : 정보통신,정보보안 Vol.12 No.6

Recently, the telecommunication network is in a transition toward the BcN (Broadband convergence Networks) that integrates the Internet, the telecommunication and the broadcasting. The BcN makes it possible to provide of 4he third-party application by using the Open API The Parlay X API is an example of the Open API and the Parlay X API is grafted in the Web Service and is abstracted from the Parlay API. So, the Parlay X API does not only have advantages of a Web Service, but also disadvantages of the Web Service. The main disadvantage of the Web Service is that it does not support the any QoS mechanism. In this paper, we propose the architecture that solves the reliability among the QoS issues for the Web Service. The proposed mechanism adopts the Asynchronous architecture for the reliable Web Service and improves the performance of the retransmission between the client and the server using the expected response time. We perform the performance evaluation through the simulation in older to compare with the existing mechanism. Consequently, we can confirm that the performance of the proposed mechanism performs better than the existing mechanism. 최근 정보통신환경은 통신, 방송, 인터넷이 통합되는 디지털 융합 서비스 제공 형태로 급속히 변화하고 있다. 이에 따라 통신환경이 개방형 네트워크 형태의 광대역통합망으로 변화하였다. 이런 광대역통합망에서는 Open API(Application Program Interface)에 의하여 감third-party 응용의 제공을 가능하게 한다. Open API에는 대표적으로 Parlay API가 있으며 Parlay API와 웹 서비스를 접목시키고 한 단계 더 추상화한 Parlay X API가 있다. Parlay X API는 웹 서비스를 이용한다. 따라서 Parlay X API는 웹 서비스의 장점을 가지고 있지만 웹 서비스의 단점도 가지고 있다. 웹 서비스의 가장 큰 단점으로는 웹 서비스에 QoS(Quality of Servixe)제공을 위한 방법이 제시되어 있지 않다는 것이다. 본 논문에서는 웹 서비스를 광대역통합망에서 효율적으로 동작시키기 위해서 QoS의 여러 문제 중 신뢰성 지원방안에 대하여 제시하고자 한다. 제안된 방안은 웹 서비스의 신뢰성 지원을 위하여 비동기 구조를 적용하고, 예상응답시간을 이용하여 클라이언트와 서버간의 재전송 효율을 증가시키고자 한다. 시뮬레이션을 통하여 성능평가를 실행하였으며 기존의 방법과 비교하여 보았다 피 결과 제안된 방범이 기존의 방법보다 좋은 성능을 보인 것을 확인할 수 있었다.

Microarray와 Network 분석을 통한 병원균 및 스트레스 저항성 관련 주요 유전자의 대량 발굴

김형민,문수윤,이진수,배원실,원경호,김윤경,강권규,류호진,Kim, Hyeongmin,Moon, Suyun,Lee, Jinsu,Bae, Wonsil,Won, Kyungho,Kim, Yoon-Kyeong,Kang, Kwon Kyoo,Ryu, Hojin 한국식물생명공학회 2016 식물생명공학회지 Vol.43 No.3

브라시노스테로이드는 식물의 생장과 발육 과정에 있어서 중요한 역할을 담당 할 뿐 아니라 생물학적/ 비 생물학적 스트레스에 대한 복합 저항성을 보인다고 알려져 있다. 따라서 본 연구에서는 브라시노스테로이드와 광범위스트레스 내성을 연결하는 중요한 생물학적 네트워크를 이해하기 위해, Agilent Arabidopsis $4{\times}44K$ oligo chip을 이용하여 브라시노스테로이드 신호가 강화된 bes1-D 계통의 전 전사체 비교분석을 수행하였다. 그 결과 bes1-D 계통에서 DEGs (Differentially Expressed Genes)를 1,091 (562 up-regulated, 529 down-regulated) 개 선발하였다. 또한 선발된 유전자들의 GO 와 단백질 상호작용 네트워크 분석을 통해 대사, 발달, 스트레스, 면역, 방어 반응에 관련된 주요 브라시노스테로이드 신호전달과 연결된 스트레스 관련 유전자군을 분리하였다. 선발된 유전자중 NB-ARC와 FLS2는 bes1-D 계통이 야생형 En-2 계통에 비해 약 6배 정도의 발현량이 증가되었으며, TIR1, TSA1, OCP3 유전자등은 bes1-D 계통이 야생형 En-2 계통에 비해 발현이 감소되었다. 또한 브라시노스테로이드 활성형 계통이 야생형 식물체 계통에 비해 가뭄 스트레스 및 병원균에 대해 저항력이 향상되었다. 따라서 microarray 분석을 통한 유전자 간 발현 네트워크와 유전체 정보를 결합하여 대단위 주요 기능 유전자들을 동정할 수 있는 방법을 고안하여 실험에 사용하였다. 이를 통해 기능 획득 돌연변이 bes1-D가 식물들이 다양한 스트레스 환경에 적응할 수 있는 반응을 조절한다는 사실을 보여주고 있다. Brassinosteroid (BR), a plant steroid hormone, plays key roles in numerous growth and developmental processes as well as tolerance to both abiotic and biotic stress. To understand the biological networks involved in BR-mediated signaling pathways and stress tolerance, we performed comparative genome-wide transcriptome analysis of a constitutively activated BR bes1-D mutant with an Agilent Arabidopsis $4{\times}44K$ oligo chip. As a result, we newly identified 1,091 (562 up-regulated and 529 down-regulated) significant differentially expressed genes (DEGs). The combination of GO enrichment and protein network analysis revealed that stress-related processes, such as metabolism, development, abiotic/biotic stress, immunity, and defense, were critically linked to BR signaling pathways. Among the identified gene sets, we confirmed more than a 6-fold up-regulation of NB-ARC and FLS2 in bes1-D plants. However, some genes, including TIR1, TSA1 and OCP3, were down-regulated. Consistently, BR-activated plants showed higher tolerance to drought stress and pathogen infection compared to wild-type controls. In this study, we newly developed a useful, comprehensive method for large-scale identification of critical network and gene sets with global transcriptome analysis using a microarray. This study also showed that gain of function in the bes1-D gene can regulate the adaptive response of plants to various stressful conditions.

NGN 서비스 구현과 성능측정

김형민,김화성,최영일,이병선,Kim Hyoung-min,Kim Hwa-sung,Choi Young-il,Lee Byung-sun 한국통신학회 2005 韓國通信學會論文誌 Vol.30 No.1B

오늘날 통신네트워크는 음성과 데이터의 통합으로 가는 것과 동시에 새로운 서비스가 요구가 증가됨에 따라서 NGN으로 변화하고 있다. NGN은 Service, Transport, Distributed Processing Environment의 3개 계층으로 구성된다. 여기서 Service 계층은 다시 애플리케이션 계층과 Service Component 계층으로 구분할 수 있다. Parlay Group은 third-party 애플리케이션 제공의 실현을 위하여, 애플리케이션과 Service Component Layer사이에 인터페이스로 개방형 Parlay API를 채택하고 있다. Parlay API를 사용함으로써 third-party 업체들은 네트워크 제공자가 제공하는 Service component위에 있는 애플리케이션 레이어 즉 새로운 애플리케이션을 개발을 하게 될 것이다. 본 논문에서는 third-party 서비스를 이용한 Third Party Call Control (TPCC) 서비스를 구현 하였다. TPCC서비스는 Parlay APl와 Parlay X APl를 사용해 각각 구현하였으며 Transport layer에서 시그널링 프로토콜로는 SIP를 사용하였다. 또한 각 구현사항들에 대하여 성능 측정을 실시하여 비교하였다. Communication network is in a transition toward the NGN (Next Generation Networks) to accommodate the explosive demand of new services. The NGN allows the third-party application provisioning by defining the networks as layers of Services, Distributed Processing Environment and Transport. Especially, the Service layer can further be divided into Application and Service Component layer. In order to realize the third-party application provisioning, the Parlay Group has adopted an open Parlay API as an interface between the Application and the Service Component layer. Using Parlay API, the third parties may develop and deploy the IT-based applications at the Application layer exploiting the service components located within network operators' domain. In this paper, we present the implementation details about the Third Party Call Control (TPCC) Service using the third-party service logic based on Parlay API and Parlay X API, when SIP is used as a signaling protocol in Transport layer. Also, we compare the performance evaluation of both implementations.

고압 전기감전시 발생한 수근관절 주위의 진구성 연부조직 결손에 대한 유리 피판술

김형민,정창훈,이기행,고영석,Kim, Hyoung-Min,Jeong, Chang-Hoon,Lee, Gee-Heng,Koh, Young-Seok 대한미세수술학회 1998 Archives of reconstructive microsurgery Vol.7 No.1

With the advent of microvascular free-tissue transfer, this single stage resurfacing method for large scar and soft tissue defects around the wrist in the patients of electrical burn has distinctive advantage over the conventional multistage pedicle-flap transfer. Between 1992 and 1996, we treated 9 cases of 8 patients who had large scar around the wrist due to old electrical burn with free flaps as a preparation of staged tendon graft. Mean age was 30.3 years and average scar area was $6{\times}11cm$. The length of time the injury and free flaps was 9 months on an average. Prior to the free flap, we performed the angiography to all patients in order to evaluate the circulation of the forearm and hand and to choose the recipient vessel. In all cases, proximal ulnar arteries in the forearm remained intact and all radial arteries remained intact in 8 of 9 cases on angiogram. The interosseous arteries were well visualized in all cases. We used the ulnar arteries as a recipient artery. The types of flaps used were f scapular cutaneous flaps, 2 dorsalis pedis flaps and a radial forearm flap. Flap survial was 100 percents with satisfactory functional and cosmetic results. Free flaps using ulnar artery as a recipient artery is one of the useful reconstruction methods for the resurfacing of large scar around the wrist in the patients of old electrical burn.

유전 알고리즘을 이용한 트러스 구조물 손상탐지

김형민,이재홍,Kim, Hyung-Mi,Lee, Jae-Hong 한국강구조학회 2012 韓國鋼構造學會 論文集 Vol.24 No.5

본 연구에서는 유전 알고리즘(GA, Genetic Algorithm)을 이용하여 트러스 구조물에서 부재의 특성변화에 의한 손상탐지를 확인하였다. 구조물의 손상 탐지를 위하여 트러스 구조물을 모델링하여 특정 부재의 탄성계수를 감소시킴으로써 구조물의 손상을 결정하였다. 트러스 구조물의 해석은 특정 하중이 가하여졌을 경우의 정적 해석을 통하여 수행하였으며, 구조물의 손상 위치와 정도는 손상을 입기전의 구조물과 손상을 입은 구조물의 각 부재 변형률의 차이를 마이크로 유전 알고리즘을 통하여 비교 분석하여 탐지하였다. 본 연구에서는 트러스 구조물의 수치 해석 예제를 모델링하여 마이크로 유전 알고리즘을 이용하여 손상 탐지를 수행하였으며, 이를 통하여 구조물의 손상 위치와 정도가 탐지되는 것을 확인하였다. This study identifies the damage detection of truss structures by using genetic algorithm(GA) from changed elements properties. To model the damaged truss structures, the modulus of elasticity of some specific elements is reduced. The analysis of truss structures is performed with static analysis by applying uniform load, and the location and extent of structural damage is detected by comparing the stain of each element of healthy truss structures with damaged truss structures using genetic algorithm. In this study, some numerical examples are presented to detect the location and extent of damage using genetic algorithm.