학술발표회 초록 : ( 공업화학 (3) ) ; 염산계추출액을 이용한 삼원촉매로부터 로듐회수

장정록(Jeong Lok Chang),김상환(Sang Hwan Kim) 한국화학공학회 1992 추계학술발표회 Vol.- No.-

골격성 3급 부정교합 환자에서 하악지시상분할골절단술 후 3D CT 영상을 이용한 하악과두 위치변화 분석

장정록(Jung-Rok Jang),최근호(Guen-Ho Choi),박영준(Young-Jun Park),김방신(Bang-Sin Kim),유민기(Min-Gi Yu),국민석(Min-Suk Kook),박홍주(Hong-Ju Park),유선열(Sun-Youl Ryu),오희균(Hee-Kyun Oh) 대한구강악안면외과학회 2009 대한구강악안면외과학회지 Vol.35 No.5

Purpose: This study was performed to evaluate three-dimensional positional change of the condyle using 3D CT after bilateral sagittal split ramus osteotomy (BSSRO) in skeletal class III patients. Patients and methods: Nine patients who underwent BSSRO for mandibular set-back in skeletal class III malocclusion without facial asymmetry were examined. Miniplates were used for the fixation after BSSRO. 3-D CT was taken before, immediately after, and 6 months after undergoing BSSRO. After creating 3D-CT images using V-works 4.0TM program, axial plane, coronal plane, & sagittal plane were configured. Three dimensional positional change, from each plane to the condyle, of the nine patients was measured before, immediately after, and 6 months after undergoing BSSRO. Results: 1. The mean value of mandibular set-back for nine mandibular prognathism patients was 7.36 mm (± 2.42 mm). 2. In the axial view, condyle is rotated inward immediately after BSSRO (p < 0.05), comparing with preoperative but outward 6 months after BSSRO comparing with postoperative (p < 0.05). 3. In the axial view, condyle is moved laterally immediately after BSSRO (p < 0.05), comparing with preoperative but regressed 6 months after BSSRO comparing with preoperative (p > 0.05). 4. In the frontal & coronal view, there is changed immediately after and 6 months after BSSRO, comparing with preoperative but no statistical difference. Conclusion: These results indicate that three-dimensional positional change of the condyle in skeletal class III patients is observed lateral displacement & inward rotation immediate after BSSRO, but the condyle in 6 months after BSSRO tends to regress to preoperative position.

구강악안면영역의 낭종에 대한 6년간의 후향적 임상 연구

최근호,장정록,박영준,문혜원,김영준,유민기,국민석,박홍주,유신열,오희균,Choi, Guen-Ho,Jang, Jung-Rok,Park, Young-Jun,Moon, Hyea-Won,Kim, Young-Joon,Yu, Min-Gi,Kook, Min-Suk,Park, Hong-Ju,Ryu, Sun-Youl,Oh, Hee-Kyun 대한악안면성형재건외과학회 2009 Maxillofacial Plastic Reconstructive Surgery Vol.31 No.5

Purpose : This study was designed to evaluate the clinical aspect of cysts which arised in the oral and maxillofacial region. Patients and Methods : We reviewed clinical record, radiograph, histopathologic and operative report of 155 patients who had been diagnosed as cysts and treated at the department of oral and maxillofacial surgery in Chonnam National University Hospital from January 2003 to December 2008. Gender, age, classifiaction, anatomic distribution, clinical sign and symptoms, treatment, complications and recurrence rate were studied. Results : 1. Among 155 patients, the male patients(64.5%) were more than the female(35.5%). 2. The average age ofthe patients was 37.2 years(ranging from 5 to 79 years). 3. In pathologic classification, radicular cyst and dentigerous cyst were most common cysts, irrespective of 73 cases(48.3%) and 35 cases(23.2%). 4. The frequently involved cystic regions were followed as mandibular molars(38.1%), and maxillary incisors(30.2%). 5. The frequent sequence of clinical symptoms was edema(29.9%), no symptom(18.9%), tenderness(13.9%), pain(11.5%) and abscess(9.4%). 6. The most prevalent treatment was the combination operation, such as cyst enucleation with extraction or endodontic treatment of the causative tooth(76.8%) 7. Among 155 cases, 2 cases that were treated using enucleation method were recurred(1.3%).

백서의 두개골 결손부에서 탈단백우골 이식 시 흡수성악의 효과

박영준,최근호,장정록,정승곤,김영준,유민기,국민석,오희균,유선열,박홍주,Park, Young-Jun,Choi, Guen-Ho,Jang, Jung-Rok,Jung, Seung-Gon,Kim, Young-Joon,Yu, Min-Gi,Kook, Min-Suk,Oh, Hee-Kyun,Ryu, Sun-Youl,Park, Hong-Ju 대한악안면성형재건외과학회 2009 Maxillofacial Plastic Reconstructive Surgery Vol.31 No.5

Purpose : This research evaluates the effect of the use of absorbable membrane barrier with deproteinized bovine bone (Bio-$Oss^{(R)}$, Switzerland) on bone healing in surgically created critical-sized defects in rat calvaria. Materials and Methods : Two standardized transosseous circular calvarial defects (5 mm in diameter) are made in each calvarium of 30 rats. These rats are divided into negative control group(n=15), positive control group(n=15) and two experimental groups(n=15). In the negative control group, defects are only filled with blood clots. In the positive control group, defects are filled with autogenous bone obtained from calvarium; in the experimental group 1, defects are filled with deproteinized bovine bone; and in the experimental group 2, defects are filled with deproteinized bovine bone with absorbable membrane. At the postoperative 1 week, 3 weeks. and 6 weeks, clinical. histologic and histomorphometric evaluations of the defects are performed. Results : 1. The grafted bone without membrane in the calvarial bone defect was scattered but, the grafted bone with membrane was stable. 2. $BioMesh^{(R)}$ membrane was absorbed beginning at 3 weeks, and was absorbed considerably at 6 weeks while maintaining the structural form of the membrane. 3. The use of membrane blocked soft tissue invasion. 4. In histomorphometric analysis. it showed the greatest amount of new bone formation in the positive control group. The amount of new bone formation was greater in the experimental group 2 than experimental group 1. At 6 weeks. the amount of new bone formation was greater in the positive control group than experimental group l(p<0.005). Conclusion : These results suggest that membrane increase the stability of grafted bone and protects from soft tissue invasion, and the use of the membrane may promote new bone formation in deproteinized bovine bone graft area.

가토의 두개골에서 티타늄 반구를 이용한 다양한 onlay bone graft시 골형성 능력

박영준,최근호,장정록,정승곤,한만승,유민기,국민석,박홍주,유선열,오희균,Park, Young-Jun,Choi, Guen-Ho,Jang, Jung-Rok,Jung, Seung-Gon,Han, Man-Seung,Yu, Min-Gi,Kook, Min-Suk,Park, Hong-Ju,Ryu, Sun-Youl,Oh, Hee-Kyun 대한악안면성형재건외과학회 2009 Maxillofacial Plastic Reconstructive Surgery Vol.31 No.6

육안적 검사결과 실험군과 대조군 모두에서 특별한 염증 소견이나 창상 이개 없이 반원 모양의 골형성이 관찰되었다. 조직학적으로 3주째에 대조군, 실험 1군, 실험2군, 실험 3군 모두 이식골 주위 및 티타늄 반구 내면을 따라 신생 골형성이 관찰되었다. 조직학적으로 6주째에 모든 군에서 3주째에 비하여 신생골 면적의 증가 및 성숙 소견이 관찰되었고, 실험2군에서는 부분적으로 이식골이 흡수되면서 신생골이 형성되는 것이 관찰된 반면, 실험 3군에서는 이식골의 흡수 소견이 관찰되지 않았다. 조직형태계측학적으로 3주, 6주 모두 자가골에서 가장 많은 신생골 형성이 나타났고, 신생골 면적 비교시 자가골, 이종골, 합성골 순으로 크게 나타났고, 각 군간의 통계학적으로 유의한 차이는 없었다(p>0.05). 본 연구결과 골유도 재생술시 골형성 능력은 자가골이 가장 좋지만, 자가골 채취가 불가능할 경우, 적절한 차폐막을 사용한 합성골과 이종골 복합 이식방식도 좋은 대체제가 될 것으로 생각된다. Purpose: This study was performed to evaluate the effect of various graft materials used with a titanium cap on the ability of new bone formation in the rabbit calvarium. Materials and Methods: A total of 32 sites of artificial bony defects were prepared on the calvaria of sixteen rabbits by using a trephine bur 8 mm in diameter. Each rabbit had two defect sites. 0.2 mm deep grooves were formed on the calvaria of sixteen rabbits by using a trephine bur 8 mm in diameter for the fixation of a titanium cap. The treatments were performed respectively as follows: without any graft for the control group (n=8), autogenous iliac bone graft for experimental group 1 (n=8), alloplastic bone graft ($SynthoGraft^{(R)}$, USA) for experimental group 2 (n=8), and xenogenic bone graft ($NuOss^{(R)}$, USA) for experimental group 3 (n=8). After the treatments, a titanium cap (8 mm in diameter, 4 mm high, and 0.2 mm thick) was fixed into the groove. At the third and sixth postoperative weeks, rabbits in each group were sacrificed for histological analysis. Results: 1. In gross examination, the surgical sites showed no signs of inflammation or wound dehiscence, and semicircular-shaped bone remodeling was shown both in the experimental and control groups. 2. In histological analysis, the control group at the third week showed bone remodeling along the inner surface of the cap and at the contact region of the calvarium without any specific infiltration of inflammation tissue. Also, there was no soft tissue infiltration. Bone remodeling was observed around the grafted bone and along the inner surface of the titanium cap in experimental group 1, 2, and 3. 3. Histologically, all groups at the sixth week showed the increased area of bone remodeling and maturation compared to those at the third week. In experimental group 2, the grafted bone was partially absorbed by multi nucleated giant cells and new bone was formed by osteoblasts. In group 3, however, resorption of the grafted bone was not observed. 4. Autogenous bone at the third and sixth week showed the most powerful ability of new bone formation. The size of newly formed bone was in decreasing order by autogenous, alloplastic, and heterogenous bone graft. There was no statistically significant difference among autogenous, alloplastic, and heterogenous bones(p>0.05). Summary: This result suggests that autogenous bone is the best choice for new bone formation, but when autogenous bone graft is in limited availability, alloplastic and xenogenic bone graft also can be an alternative bone graft material to use with a suitably guided membrane.

Collaborative Filtering기반 추천 시스템에 관한 연구

이재황(JaeHwang Lee),김용구(Yongku Kim),장정록(Jeongrok Jang),엄태광(Taekwang Um) 대한전기학회 2008 대한전기학회 학술대회 논문집 Vol.2008 No.10

본 논문은 협업 필터링(Collaborative Filtering)기반의 추천시스템에 필요한 알고리즘을 제안한다. 제안한 알고리즘은 사용자의 선호도를 Implicit Feedback을 통해 예측하는 Implicit Rating과 사용자 선호도와 컨텐츠의 정보를 바탕으로 사용자의 프로파일을 형성하는 Tag 기반의 사용자 프로파일과 P2P망 내에서 자신과 유사한 사용자 그룹을 형성하는 알고리즘으로 구성되어 있다. 제안한 알고리즘을 적용하여 Web Text기반의 CF기반의 개인화 추천시스템을 구현하였으며 구현된 프로그램을 실제 사용자에게 배포하여 Feasibility를 검증하였다.

SIP Mobility에서 링크특성정보를 이용한 스트리밍 성능 개선

이민호(MinHO Lee),박수홍(SooHong Park),장정록(JeongRok Jang),조상욱(SangWook Cho) 대한전기학회 2008 대한전기학회 학술대회 논문집 Vol.2008 No.10

모바일 단말이 이종네트워크 환경에서 멀티미디어 데이터를 스트리밍 수신받으며 이동할 때, 특성이 다른 링크로 옮겨감에 따라 스트림의 전송률이 링크의 적정 대역폭을 초과하여 정상적인 전송이 되지 않거나 링크의 적정 대역폭을 미달하여 효율적인 전송이 되지 않을 수 있다. 본 논문에서는 SIP Mobility 상황에서의 링크특성 정보 전달 방법을 고안하고, 전달받은 링크특성 정보를 통한 전송 조절 방법을 제안한다. 실제 RTP패킷 전송 실험을 통하여 스트리밍 전송 성능이 개선됨을 보인다.