삼기층(三紀層) 퇴적암(堆積岩) 중(中) 비석(沸石)의 산출상태(産出狀態)

김종환,문희수,Kim, Jong-hwan,Moon, Hee-Soo 대한자원환경지질학회 1978 자원환경지질 Vol.11 No.2

Of more than 30 varieties of zeolite group minerals, 7 varieties, mordenite, clinoptilolite, natrolite laumontite, stilbite, stellerite and chabazite are identified in Korea, whereas mordenite and clinoptilolite occur in Miocene sediments of small Yonil tertiary basin, east coast of Korea. The basin consists of three separate groups of sediments called Janggi, Gampo and Haseo, which are not correlated stratigraphyically yet. Zeolite occurs alternating with montmorillonite layers in Nuldaeri, Yongdongri and Haseori tuffs of Jahanggi, Gampo and Haseo Groups respectively. Zeolite was formed by diagenesis. of acidic volcanic tuffs.

Porous Resorbable Calcium Carbonate와 Porous Replamireform Hydroxyapatite가 성견치주질환 이환 발치와내 이식된 치근과 발치와 치조골 재생에 미치는 영향

김종환,최성호,Kim, Chong-Kwan,Choi, Seong-Ho 대한치주과학회 1996 Journal of Periodontal & Implant Science Vol.26 No.2

Regeneration of the periodontal tissue destroyed by periodontal disease is one of the final goals of periodontal therapy. In the past few years, periodontists have used various alloplastic grafting materials in an attempt to regenerate bone lost from periodontal disease. These materials have used widely because they have shown to be nontoxic, biologically compatible with surrounding host tissue and chemically similar to bone. The purpose of this study was to investigate the effect of Porous Resorbable Calcium Carbonate and Porous Replamineform Hydroxyapatite on the regeneration of the alveolar bone and the healing of roots transplanted into the periodontally diseased extraction sockets of dogs. The experimental chronic periodontitis was induced by elastic ligatures on the 2nd and 3rd mandibular premolars of 2 adult dogs for 8weeks after surgically creating periodontal defect. The extracted root were split in half along the long-axis, and the extend of plaque exposure was marked on the root surfaces with burs. The roots were inserted in extraction sockets with Porous Resorbable Calcium Carbonate(PRCC) in left side and with Porous Replaminefrom Hydroxyapatite(PRH) in right side. The flaps were sutured to cover the sockets completely. The animals were sacrificed after 12 weeks of healing, and the specimens were examined histologically. The results were as follows: 1. No inflammatory reactions were observed in either groups. 2. Hoot resorption was observed in both groups while the general outline of the roots were maintained. 3. PRCC was almost completely resorbed and replaced with new bone, while R.H.A. was not resorbed & remained encased in newly-formed C-T and alveolar bone. 4. PRH was encapsulated with alveolar bone which has been deposited from apical & lateral area of the sockets, while the coronal portion of the sockets were filled with C-T. 5. In both groups, the resorbed portions of the roots were replaced with new bone. These results suggest that either PRCC or PRH may not interfere with bone formation or healing in extraction sockets, and in some degree, retard the root resorption. Because the roots maintained in anatomy, we think that graft materials prevent the root resorption.

생활폐기물소각장 안전관리 개선 사례

김종환,Kim, Jong-Hwan 대한산업안전협회 2007 안전기술 Vol.109 No.-

Geochemistry and Genesis of the Guryonsan(Ogcheon) Uraniferous Back Slate

김종환,Kim, Jong Hwan The Korean Society of Economic and Environmental G 1989 자원환경지질 Vol.22 No.1

구룡산(九龍山)(또는 옥천(沃川)) 함(含)우라늄 흑연질점판암(黑鉛質粘板岩)은 옥천대(沃川帶) 서북부(西北部)에 따라 증상(層狀) 또는 부딘상(狀)으로 90km이상(以上) 연장(延長) 분포(分布)한다. 함(含)우라늄점판암(粘板岩)의 오토레디오그라프에 나타나는 퇴적(堆積), 속성(續成), 변성구조(變成構造)는 우라늄과 동시퇴적물(同時堆積物)로서 속성작용과정(續成作用過程)에서 전혀 이동(移動)하지 않고 황성변성(廣域變成) 초기(初期)에 제자리에서 미립(微粒)우라니나이트로 재결정(再結晶)하였음을 보여준다. 동시(同時)에 유기물(有機物)은 미세환장흑연(微細環狀黑鉛)으로 되었다. 라미나구조(構造)의 발달(發達)과 평균(平均) 19.64% C, 2.32% S의 함유(含有)는 함(含)우라늄흑니(黑泥) 퇴적(堆積)의 일반조건(一般條件)으로서의 극(極)히 낮은 퇴적화(堆積比), 고유기물함유(高有機物含有), 염기성황경등을 충족(充足)하였으며 Th/U가 0.07로서 해수원(海水源)임을 뜻한다. 지역별(地域別) CaO, $P_2O_5$의 평균치(平均値)가 매우좁은 범위(範圍)의 일정치(一定値)이며 높은 CaO 평균치(平均値)를 나타내어 전퇴적(全堆積)분지를 통(通)하여 동일(同一) pH(7.8-8.0)조건(條件)의 환경(環境)에서 퇴적(堆積)하였음을 나타낸다. 함(含)우라늄점판암(粘板岩)은 같은 성인(成因)의 타산장(他産狀)에 비(比)하여 미량원소(微量元素) 부화도(富化度)가 매우 높다. 고부화(高富化)의 중요(重要)한 원인(原因)으로서 미량원소(微量元素)의 소스(source)인 해수(海水)의 주기적(週期的) 교체(交替)가 요구(要求)되는데 사이크릭퇴적구조(堆積構造)는 그러한 현상(現象)을 뒷받침하여 준다. 흑니(黑泥)의 성인별(成因別) 구성광물(構成鑛物)과 원소(元素)의 수반관계(隨伴關係)에서 쇄설성광물(鑛物)에는 Si, Al, K, Na, Ti, Zr, Th, Be, B, Li, 유기물(有機物)후락숀에, U, Ni, Cu, Co, Zn, Ag, Mo, Pb, Sn, Cd, S, Fe, V, Cr, Y, 탄산염광물(炭酸鹽鑛物)에 Ca, Mg, Mn, P, Ba가 높은 상관(相關)을 나타낸다. 유기물(有機物)의 우라늄고정심전능력(固定沈澱能力)에 있어 사프로페릭(Sapropelic)형(型)보다 휴믹(Humic)형(型)에서 더 높다. 육성식물(陸性植物)의 분해물(分解物)인 휴무스(Humus)는 고대성(古生代) 중기(中期)에 출현(出現)한다. 우라늄 함유(含有) 흑니(黑泥)는 이 시대(時代)의 형성물(形成物)로서 이런 형(型)의 광상(鑛床)은 생물상(生物相)의 진화(進化)에 규제(規制)된 광화작용(鑛化作用)의 산물(産物)이다. Geochemical characteristics of the Guryongsan (Ogcheon) uraniferous black slate show that this is an analogue to the conventional Chattanooga and Alum shales in occurrences. Whereas, its highest enrichment ratio in metals including uranium, among others, is explained by the cyclic sedimentation of the black muds and quartz-rich silts, and the uniform depositional condition with some what higher pH condition compared to the conditions of the known occurrences. The cyclic sedimentation, caused by the periodic open and close of the silled basin, has brought about the flush-out) of the uranium depleted water and the recharge with the new metal-rich sea water, which consequently contributed to the high concentration of metals in mud. The metal-rich marine black muds, which mostly occur in the early to middle Palaeozoic times, is attributed by the geologic conditions which related to the atmospheric oxygen contents, and these are scarcely met in the late Precambrian and/or with the onset of Palaeozoic era in the geologic evolution of the earth.

영상정보에 기초한 전차 자율탐지 및 조준점탐색 연구

김종환,정치정,허미라,Kim, Jong-Hwan,Jung, Chi-Jung,Heo, Mira 한국시뮬레이션학회 2018 한국시뮬레이션학회 논문지 Vol.27 No.2

본 논문은 지상무인전투체계 중의 하나인 무인경전투차량이 RGB 영상정보를 기초로 스스로 전차를 탐지하고 조준점을 산출하는 지능형 표적획득/처리기술의 기초연구이다. 무인 경전투 차량이 전장에서 적 전차와 조우 시, 적 전차를 자율적으로 탐지하고 스스로 조준하는 방법을 개발하기 위해, 영상정보로부터 전차의 주요특징을 식별 및 추출하고, Maximally stable extremal regions, 중간값 필터, k평균 클러스터링 그리고 Morphological filtering의 영상처리기법 및 인공지능 알고리즘을 통해 전차의 외형정보를 추출 및 분석하였으며, 식별된 전차 외형정보를 벡터화하여 전차의 중앙을 지향하는 조준점을 산출하였다. 또한, 본 연구의 성능을 측정하기 위해 선진국들의 주력전차의 영상정보를 수집 및 분석하였고, 제안한 방법의 객관적인 전차탐지 성능은 정확도 91.6%, 정밀도 90.4%, 재현율 85.8% 그리고 F-measure 88.1%의 결과를 보여주었다. 본 연구가 무인전투체계의 지능형 표적획득/처리기술 연구개발에 도움이 되기를 기대한다. This paper presents an autonomous detection and aiming point computation of a battle tank by using RGB images. Maximally stable extremal regions algorithm was implemented to find features of the tank, which are matched with images extracted from streaming video to figure out the region of interest where the tank is present. The median filter was applied to remove noises in the region of interest and decrease camouflage effects of the tank. For the tank segmentation, k-mean clustering was used to autonomously distinguish the tank from its background. Also, both erosion and dilation algorithms of morphology techniques were applied to extract the tank shape without noises and generate the binary image with 1 for the tank and 0 for the background. After that, Sobel's edge detection was used to measure the outline of the tank by which the aiming point at the center of the tank was calculated. For performance measurement, accuracy, precision, recall, and F-measure were analyzed by confusion matrix, resulting in 91.6%, 90.4%, 85.8%, and 88.1%, respectively.

학술발표회 초록 ( 재료 (Ⅲ) ) : LPCVD 에 의한 탄소섬유 표면에 SiC 박막제조와 고온에서의 내산화 반응 연구

김종환,이영석,유승곤,이보성 ( J . H . Kim,Y . S . Lee,S . K . Ryu,B . S . Rhee ) 한국화학공학회 1994 춘계학술발표회 Vol.- No.-

SVM 기반 소화기 방호한계속도 측정방법 연구

김종환,백승원,윤병조,조성식,Kim, Jong-Hwan,Baik, Seungwon,Yoon, Byengjo,Jo, Sungsik 한국군사과학기술학회 2016 한국군사과학기술학회지 Vol.19 No.5

This paper presents a ballistic limit velocity measurement using the support vector machine that classifies two classes, the partial penetration and the complete penetration, by generating a linear separating hyperplane that equally divides the classes. For the ballistic limit velocity measurement, the previous methods(MIL-STD-662F and NIJ-STD-0101.06) have required a large number of experiments that caused high cost and time. However, the proposed method is not only flexible, requiring 0.85 ~ 4.8 times fewer experiments but also reliable, providing less than 2 % difference in results compared to the previous methods. For its validation, live fire experiments were conducted using various thickness SS400 iron plates as a target and two different types of live bullets such as 5.56 mm M193 and 7.62 mm M80.

Carpentier-Edwards 판막의 장기 술후성적

김종환,이영균,Kim, Jong-Hwan,Lee, Yeong-Gyun 대한흉부심장혈관외과학회 1986 Journal of Chest Surgery (J Chest Surg) Vol.19 No.1

The Carpentier-Edwards porcine xenograft valve was used in 21 patients at Seoul National University Hospital during the period between 1977 and 1979. Twenty-four Carpentier-Edwards valves were implanted along with 2 others. Three patients died within 30 days of operation, an operative mortality rate of 14.3%. Eighteen early survivors were followed up for a total 67.5 patient-years [mean, 45.0$\pm$32.0 months]. There were 2 late deaths with a linealized late mortality rate of 2.96%/patient-year; one died from cerebral bleeding [1.48% bleeding/patient-year] and the other from prosthetic valve endocarditis [1, 48% endocarditis/patient-year]. There was no case of thromboembolism. Two patients developed mitral regurgitation [2.96% failure/patient-year]. Symptomatic improvement was excellent. The actuarial survival rate and the probability of freedom from overall valve failure were 75.3$\pm$9.6% and 80.7$\pm$12.9% at 9 years after surgery respectively. During the period from October, 1968, through June, 1985, 1, 190 substitute heart valves were used in a total of 967 patients at Seoul National University Hospital; of which, 90.9% were either porcine aortic or bovine pericardial xenograft valves. For the evaluation of the xenograft tissue valves, the consecutive patients with lonescu-Shiley valve in the mitral, aortic and both positions, Angell-Shiley valve and Carpentier-Edwards valve were recently studied on the clinical ground. They were 531 patients, and 643 xenograft valves were used. The operative mortality rate was 6.97% and a linealized late mortality rate 2.94%/patient-year. A total of 490 early survivors were followed up for 917.6 patient-years [mean, 22.5 months], and 70% of patients completed the follow-up. The linealized incidences of complications were: 2.29% emboli/patient-year, 1.98% bleeding/patient-year, 1.20% endocarditis/patient-year, and 3.49% failure/patient-year. These clinical resutls are fully comparable with those in the major reports. The durability of the glutaraldehydepreserved xenograft heart valves remains as a great concern and a continuing debate, expecially for the group of patients in the pediatric age. The need of more durable material for the improved tissue valves was also discussed.

소아환자에서의 심장판막치환수술

김종환,이영균,Kim, Jong-Hwan,Lee, Yeong-Gyun 대한흉부심장혈관외과학회 1983 Journal of Chest Surgery (J Chest Surg) Vol.16 No.1

Valve replacement in children, aging up to 15 years [Mean 11.g years], has been done at Seoul National University Hospital over the past 14 years since 1968. Fifty-one patients have received 59 artificial valves: 55 bioprosthetic and 4 prosthetic valves. Thirty-one patients [60.8%] had rheumatic heart disease and the remainder [39.2%] had congenital heart disease. Forty-two patients [82.4%] survived operation: 9 patients [17.7%] died within one monfi3 postoperatively and 4 patients [7.8%]during the follow-up period with the overall mortality rate of Thromboembolic complication occurred in 3 patients with 2 deaths: 5.9% embolic rate or 4.68% emboli per patient-year. One patient who had been on coumadin anticoagulation died from cerebral hemorrhage. One mitral Ionescu-Shiley valve failed 19 months after first replacement and this was successfully re-replaced with the same kind of valve. Actuarial survival rate was 59.9% at 4 years after surgery. Thromboembolism-free and valve failure-free survivals were 80.0% and 93.1% respectively. These clinical results in the pediatric age group suggested that valve replacement in children was a serious undertaking with a higher mortality rate than in adults. However, the main superiority on the low thrombogenecity of the xenograft valve over the mechanical one warrants its continuing use until the question of its durability would otherwise be answered by a further study of clinical follow-up.

열전달 해석을 이용한 VAR 공정 변수가 티타늄 합금 잉고트 응고 조직에 미치는 영향 연구

김종환,이재현,허성강,현용택,이용태,Kim, Jong-Hwan,Lee, Jae-Hyeon,Heo, Seong-Gang,Hyeon, Yong-Taek,Lee, Yong-Tae 한국재료학회 2002 한국재료학회지 Vol.12 No.5

VAR process is required to control its various operating parameters. Heat transfer simulation has been accomplished to understand development of solidification micro and macro-structures during VAR process in Ti alloys. Optimum VAR process parameters could be also estimated in this study. It was found that macro-structures were closely related to the shape and depth of liquid pool, and solidification parameters, such as temperature gradient, heat flux, solid fraction. The cooling rates were higher at bottom, top, and center part respectively. As cooling rates increased, the $\alpha$ phase decreased in length, width and fraction. In order to evaluate which parameter affects the result of heat transfer calculation most sensitively, the sensitivities of input parameters to the simulation result were examined. The pool depth and cooling rate showed more sensitive to the temperature of the molten metal, heat transfer coefficient, and liquidus respectively. Also, these thermal properties became more sensitive at higher temperatures.