성견 1면 골 결손부에서 Polylactic/polyglycolic acid copolymer (PLA/PGA) 흡수성 차단막의 치주 조직 재생에 대한 연구

김성구,황성준,김민경,김창성,이덕연,이용근,조규성,채중규,김종관,최성호,Kim, Sung-Koo,Hwang, Sung-Joon,Kim, Min-Kyoung,Kim, Chang-Sung,Lee, Doug-Youn,Lee, Yong-Keun,Cho, Kyoo-Sung,Chai, Jung-Kiu,Kim, Chong-Kwan,Choi, Seong-Ho 대한치주과학회 2003 Journal of Periodontal & Implant Science Vol.33 No.4

The goal of periodontal treatment is regeneration of the periodontium. Bone graft and absorbable PLA/PGA membrane have been used for this purpose. In this study, 4${\times}$4mm 1-wall intrabony defects were surgically created bilaterally in the mandible of five male beagles. The control group went through a conventional flap operation, while the experimental group I was treated with absorbable PLA/PGA membranes only, group II was treated with absorbable membrane and calcium phosphate. The results are the following : 1. The defect height was 4.82${\pm}$0.45mm in the control group, 4.93${\pm}$0.79mm in the experimental I group, and 4.92${\pm}$0.62mm in the experimental II group. There was no statistically significant difference among 3 groups(P <0.05). 2. The amount of junctional epithelium migration was 30.90${\pm}$9.92% of the defect height in the control group, 39.16${\pm}$7.51% in the experimental I group, and 38.68${\pm}$12.22% in the experimental II group. There was no statistically significant difference among 3 groups(P <0.05). 3. The amount of connective tissue adhesion was 36.38${\pm}$9.03% in the control group, 14.73${\pm}$3.93% in experimental I group, and 27.87${\pm}$9.70% experimental II group. Experimental group I was a statistically significantly different from control group(P <0.05). 4. The amount of new cementum regeneration was 32.92${\pm}$10.51%, 50.04${\pm}$7.61%, and 39.62${\pm}$12.14% for the control, experimental I, and experimental II group respectively. Experimental group I was a statistically significantly different from control group(P<0.05). 5. The amount of new alveolar bone regeneration was 27.24${\pm}$7.49%, 40.75${\pm}$8.03%, and 36.47${\pm}$15.11% for the control, experimental I, and experimental II group respectively. Experimental group I was a statistically significantly different from control group(P <0.05). The results suggest that the use of PLA/PGA membrane in 1-wall intrabony defect of beagle dogs may promote periodontal regeneration. Further studies are required to determine their regeneration effects.

파괴인성의 축소모형실험 적용 연구

김종관(Jong-Gwan Kim) 한국암반공학회 2020 터널과지하공간 Vol.30 No.1

암석의 파괴인성은 발파, 굴착 등으로 인한 균열의 개시와 전파를 나타낼 수 있는 상수이다. 터널의 거동, 석회석 광산의 안정성 평가 등에 축소모형실험이 다양하게 적용되고 있다. 축소모형을 통해 발파로 인한 손상영역평가도 이뤄지고 있는데, 파괴 관련 인자에 대한 축소율 적용은 이뤄지지 않고 있다. 본 연구에서는 DCT(diametral compression test) 값과 유한요소법인 ATENA2D 수치해석 결과를 비교하여 암석의 파괴인성에 축소율을 적용할 수 있는지 확인하였다. 암석의 파괴인성에 이론적으로 계산된 축소율을 적용한 값과 DCT 시험결과 및 수치해석 결과가 각각 0.21~ 0.46, 0.40, 0.99MPa√m로 편차가 있으므로 암석의 파괴인성에 축소율을 적용 시에는 이 세 가지 값을 고려하여 적합한 축소율을 도출해야하고, 축소모형 제작 시 축소율 적용 대상이 되는 길이, 시간, 질량과 함께 이로부터 산출되는 일축압축강도, 밀도 등의 주요 설계인자들의 축소율이 적용된 값을 함께 검토해야 할 것이다. Fracture toughness of rock is a constant that can indicate the initiation and propagation of cracks due to blasting, excavation, etc. Scaled model tests have been applied to the behavior of tunnels and the stability of limestone mines. Through the scaled model, damaged zone evaluation due to blasting is also carried out, and the scale factor is not applied to the failure-related factors. In this study, DCT (diametral compression test) and finite element method ATENA2D numerical analysis results were compared to determine whether the scale factor could be applied to the fracture toughness of rock. The theoretical values of the scale factor applied to the fracture toughness of the rock and the DCT test results and the numerical results are 0.21~0.46, 0.40, and 0.99MPa√m respectively, so these three values should be considered when determining scale factor. It is necessary to derive a suitable scale factor in consideration of the length, time, and mass to which the scale factor is applied, as well as the values of the scale factor of major design factors such as uniaxial compressive strength and density.

다층 주방식 채광 광산에서 낙반이 채광장 천반과 광주에 미치는 영향

김종관 ( Jong Gwan Kim ),양형식 ( Hyung Sik Yang ) 대한화약발파공학회 2016 화약발파 Vol.34 No.4

다층 주방식 광체의 개발에서 상부 채광장 천반의 붕락이 하부 편 광주에 미치는 영향을 보기 위하여 AUTODYN으로 수치해석 하였다. 그 결과 하부 채광장 천반에서의 최대 변위와 응력은 각각 0.001mm LC 36MPa 정도였고, 광주에서의 최대 변위와 응력은 각각 0.0003 mm 및 3 MPa 정도였다. 상부 채광장의 천반암석의 절반이 붕락하는 상황을 가정했을 때 하부 채광장 천반과 광주의 손상도는 0.03 정도로 나타났다. Influence of rock fall from upper-level roofs to lower-level roofs and pillars at a multi layered room and pillar mine was numerically simulated by using AUTODYN. The analysis results showed that the maximum displacement and stress in the roof of the lower-level stope are respectively 0.001 mm and 36 MPa, and those in the pillars of the lower-level stope are 0.0003 mm and 3 MPa. The maximum damage levels in the roof and pillar of the lower-level stope were evaluated to be about 0.03 when a half of the roof rock of the upper-level stope was assumed to be fallen to the floor.

종골에 발생한 골내 지방종 - 2예 보고 -

김종관,안병우,김정환,김영오,박재규,윤종호,권오준,Kim, Chong-Kwan,Ahn, Byung-Woo,Kim, Jeong-Whan,Kim, Young-Oh,Park, Jae-Kyu,Yoon, Jong-Ho,Kwon, Oh-Joon 대한족부족관절학회 2000 대한족부족관절학회지 Vol.4 No.2

Benign cystic lesions, have to be differentiated, are common in the calcaneus, Among the lesions the intraosseous lipoma is extremely rare tumor in bone. In 1996, Unni reported 7 in 11,087 cases of bone tumors at Mayo Clinic. In Korea, Ahn reported the first intraosseous lipoma in the distal fibula. We experienced two cases of intraosseous lipoma of calcaneus, and report the clinical, radiological and pathological findings with a review of the literatures.

비대칭 V-cut의 갱내 광산에 대한 적용성 연구

김정규(Jung-Gyu Kim),정승원(Seung-Won Jung),김준하(Jun-Ha Kim),김종관(Jong-Gwan Kim) 한국암반공학회 2021 터널과지하공간 Vol.31 No.6

갱내채광개발의 안정성 문제로 굴착단면을 축소하였을 때 발생한 경제적 손실을 최소화하기 위해 발파효율을 증가시킬 필요가 있으며, 이를 위해 새로운 발파 설계를 제안하였다. 본 연구에서는 현장의 생산발파, 생산발파에 확대공을 2열 추가한 1차 제안발파 그리고 확대공에 1열만 추가하여 비대칭을 이루는 2차 제안발파의 발파효율을 비교하였다. 발파효율 평가지표로는 굴진율과 파쇄입도로 선정하였다. 굴진율의 경우 일반대비 1차 제안발파는 6.07%, 2차 제안발파는 4.65% 향상하였고, 파쇄입도의 경우 P80 기준으로 일반발파 대비 1차 제안발파는 약 58%, 2차 제안발파는 약 47% 파쇄입도가 감소하였다. 평가지표에 따라 1차 제안발파가 2차 제안발파보다 좋은 발파효율을 보이지만, 평가지표의 결과의 차이가 미비하여 1차 제안발파에 추가적으로 소요된 작업시간과 비용을 고려하였을 때 2차 제안발파인 비대칭 V-cut이 현장에 더 적합한 발파설계라 판단된다. It is necessary to increase the blasting efficiency in order to minimize the economic loss caused when the excavation cross section is reduced due to the stability problem of underground mining development, and for this, a new blasting design is proposed. In this study, the blasting efficiency of the general design in the field, the suggestion designⅠ, which added two columns to production blasting, and the suggestion design II, which added one column to create asymmetry, is compared. Advance rate and fragmentation were selected as the evaluation index of the blasting efficiency. In the case of advance rate, compared to the normal, the suggestionⅠ improved by 6.07% and the suggestionⅡ improved by 4.65%. In the case of fragmentation, based on P80, compared to the normal, the suggestionⅠ reduced about 58% and the suggestionⅡ was about 47%. Accoording to the evaluation index, the suggestion designⅠ shows better blasting efficiency than the suggestion designⅡ. But considering the additional work time and cost required for the suggestion designⅠ due to the insignificant difference in the evaluation index results, the asymmetry V-cut, the suggestion designⅡ, is judged to be a more suitable blasting design for the site.

머신러닝을 이용한 검색량 기반 악성 URL 탐지기법 연구

김종관(Jongkwan Kim),장민해(Minhae Jang),임선아(Suna Lim),김명수(Myongsoo Kim) 대한전기학회 2021 전기학회논문지 Vol.70 No.1

As internet technology develops and there are increases in cyber activities such as e-mail, SNS and e-commerce, cyber security is being emphasized as one of the most important social issues. In particular, spam mail, SMS phishing and other malicious URLs to breach personal data are inflicting financial and physical damage. This paper proposes a malicious URL detection method based on search volume from internet search engines to resolve such problem. The search volume-based malicious URL detection method uses portal search engines to automatically search URLs linked to emails, text messages and SNS to determine whether or not they can be categorized as malicious URLs according to the volume of the search result. This method allows normal URLs, but will protect to abnormal behaviors.

대퇴골 전자간 골절 후 발생한 정맥혈전색전증과 표재대퇴동맥 패색증 -증례 보고-

김종관 ( Chong Kwan Kim ),안병우 ( Byung Woo Ahn ),김상민 ( Sang Min Kim ),강승훈 ( Seung Hoon Kang ),한계영 ( Kye Young Han ) 대한고관절학회 2013 Hip and Pelvis Vol.25 No.4

고관절 주위 골절은 노년층이 증가함에 따라 증가하고 있고 수상 및 수술 후 발생하는 정맥혈전색전증은 생명을 위협하는 치명적인 합병증을 유발할 수 있다. 본원에서는 과거력 상 폐색전증을 진단받았으나 추시 소실 되었던 환자에서 대퇴골 전자간 골절이 발생한 후 폐색전증이 재발 하였고 항응고제를 이용하여 치료 하였다. 수상 18일 후 고관절 반치환술과 대전자 고정을 위한 갈고리금속판을 이용한 고정술을 시행하였다. 수술 다음날 정맥 혈전색전증 및 표재 대퇴동맥 패색증이 발생하였고 이 증례를 경험하여 이를 문헌고찰과 함께 보고하고자 한다. As the elderly population increases, occurrence of hip fractures has shown a rapid increase, and posttraumatic and postoperative venous thromboembolism can lead to fatal complications. Current prophylactic management includes mechanical and chemical prophylaxis. A 76-year-oldfemale, who was lost to follow-up after diagnosis of pulmonary thromboembolism four years ago, was admitted to our emergency room for a right intertrochanteric fracture. Before the operation, the thromboembolism recurred and was treated with anticoagulation medication. Bipolar hemiarthroplasty and fixation of the greater trochanter with a hook plate were performed 18 days after the trauma. Superficial femoral artery obstruction and venous thromboembolism occurred on the first day after the operation.

원위 전완부에서 요골 동맥의 주행 변이로 발생된 표재성 요골 신경 압박증 - 1례 보고 -

김종관,안병우,곽완섭,조제일,김우식,윤종호,Kim, Chong-Kwan,Ahn, Bung-Woo,Kwak, Wan-Sub,Jo, Jae-Il,Kim, Woo-Sik,Yoon, Jong-Ho 대한미세수술학회 2006 Archives of reconstructive microsurgery Vol.15 No.1

A 57-year-old male suffered from tingling and paraesthesia on radial side of right hand. We carried out exploration, the process being done, a radial artery passing between the two branches of bifurcated superficial radial nerve was found by accident. Then we performed dissection of the radial artrery a little more distally. It was passing above the extensors of thumb to anstomical snuff box. We treated it with ligating the radial artery, which was done a little above the bifurcated site of superficial radial nerve after angiography of upper extremity. While we were following this procedure, we noticed that symptoms had improved a lot. To our knowlege, neuropathy, by itself of superficial radial nerve by the radial artery with anatomical variation has never been reported and therefore we report this case.

쥐노래미 , Hexagrammos otakii 의 위내용물 분석

김종관(Chong Kwan Kim),강용주(Yong Joo Kang) 한국수산과학회 1997 한국수산과학회지 Vol.30 No.3

Stomach contents of fat greenling, Hexagrammos otakii were analyzed to understand feeding ecology of the fish in the coastal waters, Shinsudo, Sachon. Specimens were collected by angling and by gill net from February 1984 to September 1985. The fish consisted of 4 age groups from 0 to 3. The food items of the fish changed slightly by seasons and with growth of the fish. Main preys were copepods, gammarids and caprellids for the fish of age group 0, gammarids and caprellids for age group 1, and brachyurans and carideans for age group 2 and 3. The prey composition of the fish were more varied by seasons than by ages. Food items was not different between male and female of the fish. The fish positively selected for gammarids, polychaetes and brachyurans, but negatively selected for gastropods. The degree of selectivities for the other preys were changed with growth. As the fish grows it consumed larger preys in case of small preys such as gammarids and caprellids, however, it did not consumed larger preys beyond an optimal size in case of large preys such as sphaeromids, brachyurans and polychaetes.

비구골절을 동반한 양측 외상성 고관절 후방탈구 -증례보고-

김종관 ( Kim Jong Gwan ),윤종호 ( Yun Jong Ho ),안병우 ( An Byeong U ),정재익 ( Jeong Jae Ig ),김권호 ( Kim Gwon Ho ),정국상 ( Jeong Gug Sang ),김강훈 ( Kim Gang Hun ) 대한고관절학회 2003 Hip and Pelvis Vol.15 No.1