2·3차원 준연계 모형을 이용한 남강댐 하류부 흐름 및 BOD 수송 해석

김지훈,송창근,김영도,서일원,Kim, Ji-Hoon,Song, Chang-Geun,Kim, Young-Do,Seo, Il-Won 한국수자원학회 2012 한국수자원학회논문집 Vol.45 No.3

남강댐 하류는 부산 경남의 수자원 장기 계획에 중요한 지역이므로 지속가능한 지표수 관리 및 오염원 제어를 위해 흐름 및 수질 해석이 필요하다. 따라서 본 연구에서는 2차원 수질모형인 RAM4와 3차원 수질모형인 WASP을 각각 수리모형인 RAM2 및 EFDC모형과 연계하여 2 3차원 준연계 모형을 이용한 남강댐 하류에서의 수리 및 수질을 해석하였다. 2차원 흐름해석 모형인 RAM2 적용 결과 만곡부 5개 횡단 측선에서의 유속의 증감경향이 ADCP 실측값과 잘 일치하였으며, 3차원 모형인 EFDC와 유속 분포 및 보 월류 유속이 유사하였다. 또한 정상상태 도달 후의 RAM2-RAM4 연계모의에 의한 BOD 농도와 EFDC-WASP 연계모의에 의한 BOD 농도장이 모의영역 전반에 걸쳐 유사하게 나타났다. 남강댐 하류부의 경우 수리 및 수질이 남강댐 방류량에 크게 좌우되며 남강댐의 수량은 하류부의 수질 및 연안 어업환경에 큰 영향을 미치므로 향후 이에 대한 정량적 분석 시 계산의 효율성 및 모형의 적용성 측면에서 2차원 준연계 모형을 적용하는 것이 바람직한 것으로 판단된다. The downstream of the Nam River Dam is crucial region for long-term water resource planning for Busan and Gyeongnam Province. Thus, the analysis of flow behavior and water quality is necessary for the sustainable surface water management and the control of pollutant source. In this study, the flow field and BOD transport at the downstream of Nam River Dam were analyzed by incorporating 2-D water quality model, RAM4 and 3-D water quality model, WASP with the hydrodynamic model, RAM2 and EFDC, respectively. The application of 2-D flow analysis model, RAM2 showed that velocity distributions at the five transverse sections of the meandering part closely followed the measured values by ADCP, and the flow field and overflow characteristic at the submerged weir showed satisfactory performance compared with the result of 3-D EFDC model. In addition, the BOD concentration field obtained by RAM2-RAM4 coupled modeling was in good agreement with the result by EFDC-WASP model throughout the computational domain. The hydrodynamic characteristic and water quality at the downstream reach of Nam River Dam are mainly influenced by the Dam discharge, and the water quantity is closely related to the water quality control and fishery environment at the lower part of Nakdong River. Therefore, when further quantitative analysis is necessary regarding these issues, 2-D semi-coupled modeling is recommended in terms of computational effectiveness and model application aspect.

$La_2CuO_4$ 구조를 갖는 $(C_4H_9NH_3)_2PbI_4$의 합성 및 분석

김지훈,박성훈,최동식,Kim, Ji Hoon,Park, Sung Hoon,Chair, Tong Seek 대한화학회 1998 대한화학회지 Vol.42 No.5

백부자산(白附子散)이 자외선 조사된 피부 손상과 색소침착에 미치는 영향

김지훈,홍승욱,Kim, Ji-Hoon,Hong, Seong-Ug 대한한방안이비인후피부과학회 2008 한방안이비인후피부과학회지 Vol.21 No.1

Objective : The purpose of this study is to examine the effects of Baickbujasan(BB) on the skin damage and depigmentation. Method : The inhibition of tyrosinase activity, melanogenesis and cell viability in cultured B16 melanoma cells were measured. In order to test effects of reduction of melanogenesis, B16 F-10 mouse melanoma stem line was employed to extract melanin from cultured cell, where BB was added or not, and was dissolved in alkali for colorimetric analysis. Also, in order to test skin alteration in C57BL/6 after UV irradiation, the animals were grouped into a UV urradiation group and UV irradiation after BB application group. Dopa oxidase tissue staining was excuted to invesitage the change in the distribution of active melanin cell. The distribution of active melanin cell in inner skin of iNOS after damage from UVB irradiation and the manifestation condition of P53 which takes part in natural death of keratinocyte were examined. Result : The results indicate that BB has significant effects on tyrosinase activity, and melanogenesis in vivo test. BB seems to reduce C57BL/6, external dermatological damage, for instance, erythematous papule, eczema, loss of keratinocyte, reduction in pus, and relieves dermatological damages. Conclusion : BB can be applied externally for UV protection and depigmentation.

소족지 변형에서 시행한 관절 절제 성형술

김지훈,박형준,서진수,Kim, Ji Hoon,Park, Hyung Jun,Suh, Jin Soo 대한족부족관절학회 2014 대한족부족관절학회지 Vol.18 No.4

Purpose: The objective of this study was to examine the clinical results and effectiveness of resection arthroplasty for correction of lesser toe deformity. Materials and Methods: From January 2000 to November 2012, 92 cases of resection arthroplasty for lesser toe deformity were reviewed. Hammer toe was the most common type of deformity, accounting for 44 toes (33 patients). Hallux valgus was the most common comorbid illness. Second toe was the most commonly affected toe and proximal interphalangeal joint was the most common location of resection arthroplasty (69 toes, 75.0%). We also analyzed the alignment of phalanges using the last follow-up weight bearing radiographic image. The analysis included clinical evaluation with American Orthopaedic Foot and Ankle Society (AOFAS) score as well as subjective satisfaction. Results: Flexor tenotomy (19 cases) was the most common combined surgery. Floating toe (4 cases) was the most common complication. The last follow-up alignment of phalanges was better than good in 71 toes (77.2%) in anteroposterior view and in 69 toes (75.0%) in lateral view. Sixty one cases (85.9%) resulted in better satisfaction than 'good' and the final average AOFAS score was 87.4. Conclusion: Resection arthroplasty is a valuable surgical option for treatment of lesser toe deformity, with high patient satisfaction, easy surgical technique and remarkable correction of deformity.

B형 및 C형 간염의 이해

김지훈,Kim, Ji-Hoon 한국생명보험의학회 2011 保險醫學會誌 Vol.30 No.1

Both the enterically transmitted forms of viral hepatitis, hepatitis A and E are self-limited and do not cause chroni chepatitis. Chronic hepatitis occurs in patients with hepatitis B and C as well as in patients with chronic hepatitis D superimposed on chronic hepatitis B. Chronic hepatitis such as hepatitis B or C is important in terms of insurance underwriting and claims. General review of hepatitis B and C was performed in this article.

절단 위치에 따른 족부 절단술의 치료 결과

김지훈,고형탁,서진수,Kim, Ji Hoon,Ko, Hyeong Tak,Suh, Jin Soo 대한족부족관절학회 2015 대한족부족관절학회지 Vol.19 No.1

Purpose: The purpose of this study is to evaluate the incidence and cause of reamputation with respect to the location of foot amputation. Materials and Methods: Eighty-six patients who received amputations below the ankle level from March 2002 to September 2012 with at least 1 year follow-up were enrolled in this study. We stratified the site of the initial amputation from first to fifth ray and into either the phalanx or metatarsal bone, and investigated the cause of reamputation. Results: The reamputation rate below the ankle level was 53.5%. It was highest (62.1%) in patients with first ray amputations without statistical significance. Rays were divided into two columns, first to third rays as the medial column and others as the lateral column, and reamputation was performed in 61.2% of patients with medial column amputation. Comparing the results between phalanx and metatarsal amputations, reamputation was performed in 62.1% of patients with metatarsal bone amputation. The rate of reamputation was statistically significant in both the medial column and metatarsal amputations. The most common reamputation site, in accordance to the initial site of amputation, was the adjacent ray (57.4%), which was without statistical significance. Moreover, the most common cause of reamputation was osteomyelitis and focal infection in all rays. Conclusion: This study showed that reamputation after amputation below the ankle level was relatively common with highest rate in medial column and metatarsal amputations. Hence, surgeons should be aware of the risk of reamputation and put more preventive effort during medial column and metatarsal amputations.

소아 궤양성 대장염의 수술적 치료 성적

김지훈,김현영,정성은,박귀원,김우기,Kim, Ji-Hoon,Kim, Hyun-Young,Jung, Sung-Eun,Park, Kwi-Won,Kim, Woo-Ki 대한소아외과학회 2005 소아외과 Vol.11 No.2

Ulcerative colitis, an inflammatory bowel disease, is primarily managed medically with a combination of 5-ASA and steroids. However, this chronic disease requires surgical management if symptoms persist or complications develop despite medical management. The clinical course, indications and outcome of surgical management of 21 patients under the age of 15 who were endoscopically diagnosed with ulcerative colitis at the Seoul National University Children's Hospital between January, 1988 and January, 2003 were reviewed. Mean follow up period was 3 years and 10 months. The mean age was 10.3 years old. All patients received medical management after diagnosis and 8 patients (38 %) eventually required surgical management. Of 13 patients who received medical management only, 7 patients (53 %) showed remission, 4 patients are still on medical management, and 2 patients expired due to congenital immune deficiency and hepatic failure as a result of sclerosing cholangitis. In 8 patients who received surgical management, the indications for operation were, 1 patient sigmoid colon perforation and 7 patients intractability despite medical management. The perforated case had a segmental colon resection and the other 7 patients underwent total colectomy with ileal pouch-anal anastomosis. One patient expired postoperatively due to pneumonia and sepsis. and 1 is still on medical management because of mild persistent hematochezia after surgery. Six other operated patients are doing well without medical therapy. Pediatric ulcerative colitis patients can be surgically managed if the patient is intractable to medical management or if complications such as perforation are present. Total colectomy & ileal pouch-anal anastomosis is thought to be the adequate surgical method.

Double-layered Peer-to-Peer Systems in MobileAd-hoc Networks

김지훈,양성봉,Kim, Ji-Hoon,Yang, Sung-Bong Korea Information Processing Society 2010 정보처리학회논문지 C : 정보통신,정보보안 Vol.17 No.1

모바일 기술이 발전함에 따라 모바일 장치들간의 파일 검색 문제가 더욱 중요한 문제로 부각되었다. 본 논문에서는 2계층 구조를 갖는 모바일 애드혹 네트워크에서 파일을 효율적으로 검색하기 위한 uniform grid, greedy, MIS P2P 시스템들을 제안한다. 이 시스템들에서 피어들은 슈퍼 피어와 서브 피어 2가지로 분류되고, 각 슈퍼 피어는 주변의 서브피어들을 관리한다. 제안하는 시스템들에서 피어가 파일 검색을 요청할 때, 검색 쿼리 메시지는 네트워크의 슈퍼 피어들을 통해서 전달되며, 이를 위해 각 슈퍼 피어는 이웃 슈퍼 피어를 연결하는 경로 역할을 하는 서브 피어들을 유지한다. 따라서 제안하는 시스템들은 멀티 브로드캐스팅을 피할 수 있고 네트워크 오버헤드를 줄일 수 있다. 실험 결과 제안하는 시스템들은 원하는 파일을 찾기 위한 평균 메시지 수를 통하여 1계층 P2P 시스템보다 좋은 성능을 보였다. 특히, 그 중 MIS는 동일한 탐색 정확도를 유지하면서 평균 메시지 수가 48.9% 줄어드는 성능 향상을 보였다. As the mobile technology advances, file searching among the mobile device users becomes more important. In this paper, we propose the uniform grid, greedy, and MIS P2P systems that have double-layered topology to search files efficiently for mobile ad-hoc networks. In these systems, peers are classified into two groups, super-peers and sub-peers, and each super-peer manages its neighboring sub-peers. In the proposed systems, each super-peer maintains the appropriate information of its sub-peers so that when a peer requests a file, the request is sent to its super-peers and then to neighboring super-peers. Hence the proposed systems could avoid multi-broadcasting and reduce network overheads. The experimental results show that the proposed systems outperform a single-layered P2P system in terms of the average number of messages to find target files. Especially the MISsystem improves by reducing the average number of messages by 48.9% while maintaining the same search accuracy.

부산 주변 해역 해저 퇴적물 내 공기층 가스 기원

김지훈,한현철,정태진,이영주,Kim, Ji-Hoon,Han, Hyun-Chul,Cheong, Tae-Jin,Lee, Young-Joo 한국석유지질학회 2007 한국석유지질학회지 Vol.13 No.1

본 연구의 주요 목적은 대한해협 대륙붕 이토대 지역의 천부 공기층 가스의 기원을 규명하는데 있다. 채취한 시료의 공기층 가스 분석 결과에 의하면 천부 공기층 가스의 대부분은 메탄으로 구성되어 있으며, 메탄 내 탄소 및 수소 동위원소 값은 각각 $-93.4%o{\sim}-70.9%o{\sim}\;-228%o{\sim}-199%o$ 가진다. 이러한 분석결과는 천부 공기층 가스 내 메탄가스가 열기원(thermogenic) 가스보다는 이산화탄소 환원작용($CO_2$ reduction)에 의한 생물 기원(biogenic) 가스임을 지시한다. 또한 메탄과 이산화탄소의 탄소 동위원소비 차는 54.4에서 72.2의 범위를 가지고 있으며, 이러한 결과 역시 전기한 결과를 뒷받침하는 또 다른 증거이다. The main purpose of this study is to identify the shallow gas origin in the KSSM zone. Based on the results of gas composition and isotope in the headsapace gas, the shallow gas is mainly composed of methane and carbon and deuterium isotopes (${\delta}^{13}CCH_4$ and ${\delta}DCH_4$) of methane has ranged from -93.4%o to -70.9%, and from -228%o to -199%o in each. These results imply that shallow gas has predominately biogenic source by $CO_2$ reduction rather than thermogenic. The carbon isotopic separation (${\varepsilon}_c$) between methane and carbon dioxide $(CO_2)$ has a range of 54.4 to 72.2, it also supports biogenic origin of shallow gas.

대형등명기 모니터링 시스템 설계 및 구현

김지훈,예성현,한순희,Kim, Ji-Hoon,Ye, Seong-Hyeon,Han, Soonhee 한국정보통신학회 2014 한국정보통신학회논문지 Vol.18 No.10

우리나라는 해안선이 복잡하여 연안을 항해하는 선박이나 어선의 안전한 항해 및 조업을 위해 효과적인 항로표지 운영이 필요하다. 특히 대형등명기는 야간에 항상 점등되어 선박의 안전을 보장해야 한다. 등대에 설치된 대형등명기가 점등되지 않을 경우 자신의 선위를 확인할 수 없어 사고가 발생하기 쉬우며 이는 커다란 경제적 피해를 야기할 수 있다. 본 연구에서는 대형등명기의 상태정보를 감시 제어하는 대형등명기 모니터링 시스템을 설계하고 구현하였다. 이 시스템은 다양한 장애상황에 신속히 대처하여 해양 안전사고를 미연에 방지할 수 있도록 하는데 그 목적이 있다. Our country has a convoluted coastline and the marine weather fluctuates locally, so it needs effective AtoN operation for the safe navigation of vessels and fishing boats sailing the coast. Especially, large beacon must ensure the safety of the vessels and always lit at night. If large beacons installed in the lighthouse are not lit, vessels can not assure their location. Thus the accidents is likely to occur, which can cause great economic damage. In this paper, we developed a monitoring system of large beacon to monitor and control the status of information. This system was designed for a special purpose of taking precautions against possible accidents on the sea.