후포분지 홀로세 퇴적물의 유기물에 대한 지화학 분석 결과 및 의미

김지훈,박명호,공기수,한현철,정태진,최지영,김진호,강무희,이치원,오재호,Kim, Ji-Hoon,Park, Myong-Ho,Kong, Gee-Soo,Han, Hyun-Chul,Cheong, Tae-Jin,Choi, Ji-Young,Kim, Jin-Ho,Kang, Moo-Hee,Lee, Chi-Won,Oh, Jae-Ho 대한자원환경지질학회 2010 자원환경지질 Vol.43 No.1

Geochemical approaches on the two recovered piston cores were performed to understand the characteristics of organic matters and the influence of the sea level variation of the East Sea in the Hupo Basin since the Holocene. The analyzing results on organic components (TOC and TN), and isotopic compositions of organic matters showed the variation to core locations and sampling depths. In core 08HZP-01, their values were gradually changed with depth from 4 mbsf to seafloor. However, rapid variation was observed at the boundary of 4.71 mbsf (meter below seafloor) in core 08HZP-03. Based on TOC/TN, $\delta^{13}C_{org}$ and $\delta^{15}N_{org}$, the origin of organic matters in the Hupo Basin can be divided into three groups; 1) predominant marine algae, 2) $C_3$ land plant, and 3) mixture of $C_3$ land plant and marine/freshwater algae. It is likely that the vertical and spatial variations of organic and isotopic compositions reflect the shifts in sedimentary environment (including sediment transportation) by ocean currents and sea-level changes and others during the Holocene period. 동해안의 후포분지에서 채취한 두 개의 피스톤 코어를 이용하여 후포분지에서의 홀로세 퇴적물 내 유기물의 특징 및 동해 해수면 변화와의 관계를 규명하고자 지화학적 접근을 시도하였다. 채취한 시료에 대한 유기물 성분 분석(TOC와 TN)과 유기물 동위원소($\delta^{13}C_{org}$와 $\delta^{15}N_{org}$) 분석 결과들은 코어와 시료 채취 심도에 따라 분석값들이 특징적으로 변화한다. 코어 08HZP-01에서는 4 mbsf(meter below seafloor)에서 코어 표면까지 비교적 채취 심도가 상부로 갈수록 지화학 분석값들이 점이적으로 증가하지만, 코어 08HZP-03에서는 4.71 mbsf를 기준으로 상부와 하부에서 급격한 지화학 분석값들의 변화가 발생한다. 유기물의 TOC/TN과 $\delta^{13}C_{org}$와 $\delta^{15}N_{org}$의 값을 종합적으로 고려하였을 때, 후포분지의 유기물은 해양 조류 기원이 우세한 집단, $C_3$ 육성 식물 기원이 우세한 집단, 해성/육성 조류와 $C_3$ 육성 식물의 혼합기원이 우세한 집단으로 구분할 수 있다. 이러한 퇴적물 내 유기물의 심도에 따른 특성 및 기원 변화는 주로 홀로세 동해 해류와 해수면 등의 변화에 따른 퇴적환경 변화 (퇴적물 이동 포함)에 기인한 것으로 보인다.

시뮬레이션을 적용한 차량부품 경량화 플라스틱 브래켓 사출 신뢰성 평가

김치중(Chi Joong Kim),박은솜(Eun Som Park),전우주(Woo Joo Jeon),박찬주(Chan Joo Park),김지훈(Ji Hoon Kim) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.3

CFRP FEM 비선형 해석을 위한 물성치 재확립에 관한 연구

김정호(Kim Jung Ho),김치중(Chi Joong Kim),차천석(Cheon Seok Cha),김지훈(Kim Ji Hoon) 한국생산제조학회 2012 한국생산제조학회지 Vol.21 No.4

To reduce these costs and time by finite element analysis program has been much research (3~4). At virtual CAE program as like Abaques, Ansys, Ls-dyna and Nastran, the input data of material is got bellow coupon test. In case of carbon composite, it is also put in lamina/laminate properties. There have big problem. If you want to simulate FW(filament winding or wind blade) how do you input material data. Each area of FW is different stacking conditions. It’s too hard that each area is tested for inputting lamina or laminate properties. The composite structure increasing load is applied occurred as the matrix dependence of the crack-induced nonlinearity and nonlinear mobility appears since the initial damage. And uni-direction for this research applies the theory to have been confined to. On this study, we are going to get basically fiber properties and matrix than carbon composite properties for simulating according stacking method by GENOA-MCQ. It is help to simulate easily composite material. Also Calculate the matrix nonlinear for simulating non-linear

울산 지역 암석 시료의 스펙트럼 특성과 이의 Clustering 응용

박종남 ( Jong Nam Park ),김지훈 ( Chi Hoon Kim ) 大韓遠隔探査學會 1990 大韓遠隔探査學會誌 Vol.6 No.2

Study was made on the spectral characteristics of rock samples including bentonites collected from the northern Ulsan area. The geology of the area consists mainly of sediments of the Kyongsang Series and Bulguksa granite, the Tertiary volcanics, andesites and tuffs. Relative reflectances of meshed samples(2.5~10mm) to BaSO4 are measured at 6 Landsat TM spectral windows(excluding the thermal band) with HHRR, and their reflection charactristics were analysed. In addition, three different data selection schemes including the Eulidean distance, multiple regression, and PCA weight methods were applied to the 30 TM ratio channels, derived from the above 6 bands. The selected data sets were subject to two unsupervised classification techniques(FA and ISODATA) in order to compare the effectiveness for classification of particularly bentonite from others. As a result, in ISODATA analysis the multiple regression model shows the best, followed by the Euliean distances one. The PCA weight model seems to show some confusion. In FA, though difficult for quantitative analysis, the best still seems to be the regression model. Among ratio bands, ratios of band 7 or 5 against other bands represent the best contribution in classification of bentonites from others.

충돌제트에 의한 덕트내 사각발열체의 냉각특성에 관한 수치해석적 연구

윤정호,김시범,김동균,이치우,김지훈,Yoon Jeong-Ho,Kim Si-Boem,Kim Dong-Kyun,Lee Chi-Woo,Kim Ji-Hoon 한국마린엔지니어링학회 2005 한국마린엔지니어링학회지 Vol.29 No.1

Because Impinging jet has excellent heat & mass transfer characteristics. it has many advantages of cooling. drying. etc and widely applied at industrial fields. Therefore, there have been many experimental investigations and theoretical studies about Impinging jet. The present study is about a cooling characteristic by Impinging jet for a Square Plate on Duct and investigated this characteristic through three-dimensions numerical analysis, using FLUENT. As the result of this study, heat transfer effect is the most appropriate condition when the ratio of distance is 6 between nozzle exit diameter and heat source. diameter of duct is 90mm and height of duct is 60mm. In addition. under the influence of injected jet. stagnant fluid flow into free jet field and this affected the whole flow field. So the shape of duct is a important factor and the researcher confirmed the need of investigation about duct.

열원 입력과 비드 생성 방법이 원통형 다층 금속 용접 과정의 유한요소해석에 미치는 영향

박원동(Won Dong Park),반치범(Chi Bum Bahn),김지훈(Ji Hoon Kim) 대한기계학회 2017 大韓機械學會論文集A Vol.41 No.6

본 논문에서는 원통형 다층 이종 금속 용접부를 대상으로 유한요소 해석을 수행하여, 열원 입력 방법과 용접 비드 생성 방법이 용접 잔류 응력 분포에 미치는 영향을 고려하였다. 열원 입력 방법은 열속 입력 방법과 온도 경계조건 입력 방법으로 나누어 비교하였고, 용접 비드 생성 방법은 요소망 생성 방법과 평온 요소망 방법으로 나누어 비교하였다. 두 열원 입력 방법에 따른 열 해석 결과는 차이가 있었으나, 응력 해석 결과는 유사하였다. 이것은 고온(약 1000 ℃ 이상)에 노출되었던 영역이 비슷하고, 고온에서 재료의 강도가 매우 낮아 용접 비드의 온도가 용접잔류응력에 미치는 영향이 미미하기 때문이다. 두 용접 비드 생성 방법의 용접 잔류응력 분포는 유사하였지만 요소망 생성 방법 적용 시 용접 비드 경계에서 겹침과 들뜸이 발생하였다. 대변형이 발생하는 모델의 용접부 형상을 정확하게 모사하기 위해서는 평온요소망이 더 적합하다고 판단된다. In this study, a finite element analysis of a cylindrical multi-pass weldment for dissimilar metals was performed. The effects of the heat input method and weld bead generation method were considered. We compared two heat input methods: the heat flux method and the temperature method. We also compared two weld bead generation methods: the element birth method and the quiet element method. Although the results of the thermal analysis show deviations between the two heat input methods, the welding residual stresses were similar. Because the areas exposed to high temperature were similar and the strength of the material was very low in high temperature (above the 1000 ℃), the effects of the weld bead temperature were insignificant. The distributions of the welding residual stress were similar to each other. However, gaps and overlaps occurred on the welding boundary surfaces when the element birth method was applied. The quiet element method is more suitable for a large deformation model in order to simulate a more accurate weld shape.

Clinical Significance and Outcomes of Initial No Growth Peritonitis from Peritoneal Dialysis Patients: Role of Mycobacterial or Fungal Peritonitis

오국환 ( Kook Hwan Oh ),이성우 ( Seong Woo Lee ),박재윤 ( Jae Yoon Park ),정종철 ( Jong Cheol Jeong ),안신영 ( Shin Young Ahn ),박진주 ( Jin Joo Park ),서원우 ( Won Woo Seo ),김지훈 ( Chi Hoon Kim ),이사민 ( Sah Min Lee ),황진호 ( 대한신장학회 2010 Kidney Research and Clinical Practice Vol.29 No.6

Purpose: Peritoneal dialysis associated peritonitis (PD peritonitis) is an important complication in maintaining. There have been only a few reports on the clinical outcome of initial no-growth peritonitis (INGP). Methods: We reviewed 332 episodes of PD peritonitis between January 2002 and August 2009. INGP was defined as PD peritonitis with no growth of etiologic microorganism within 3 days of peritonitis. INGP was compared with initial positive growth peritonitis (IPGP) in view of clinical manifestations and outcomes. Results: We divided PD peritonitis episodes into two groups: INGP (n=90) and IPGP (n=242). Peritonitis-related mortality was 5.6 % in INGP, while 0.8 % in IPGP (p=0.017). Further relapse was noted in INGP (10.0%) than in IPGP (vs. 4.1%; p=0.041). Salvage antibiotics were used more frequently in INGP (21.1%) than in IPGP (vs. 11.6%; p=0.027). Odds ratio of INGP to IPGP for peritonitis-related mortality was 7.14 (95% CI 1.36-37.51; p=0.017). Growth of mycobacteria or fungi increased the risk of peritonitis-related mortality with an odds ratio of 18.11 (95% CI 2.99-109.89; p=0.013). In multivariate analysis, growth of mycobacteria or fungi was the only independent risk factor for peritonitis-related mortality with an odds ratio of 10.63 (95% CI 1.27-88.75; p=0.029). Conclusion: INGP revealed poorer outcome than IPGP. Higher growth rate of mycobacteria or fungi in INGP than in IPGP accounted for the poor outcome. Thus one should make vigorous efforts to detect surreptitious organism when there is no growth by 3 days, especially for the possibility of either mycobacteria or fungi.

출혈을 동반한 위 평활근육종 1예

김지훈,정인식,김부성,박두호,최종영,송치원,이동수,김상우,송호진,양영상,유승철,변병훈 대한소화기내시경학회 1998 Clinical Endoscopy Vol.18 No.5

Leiomyosarcoma accounts for 1-3% of all the gastric malignancies. The most common clinical presentation of gastric leiomyosarcoma is gastrointestinal hemorrhage due to tumor ulceration. Surgical resection is the treatment of choice for gastrointestinal sarcomas and the appropriate surgical management requires deliberate efforts for complete excision of the tumor with an adequate margin of normal tissue. A 70-year-old woman was admitted to our hospital due to a melena persisting for 7 days. A gastrofiberscopy was performed and a large normal mucosa covered lobulated mass with deep multiple round ulcers were found in the fundus. A slightly protruding vessel was visible on the base of the posterior wall of the fundus. An abdominal CT revealed a heterogenous mass with irregular multifocal necrotic portions in the fundus. During on operation, a tumorous mass was found in the fundus. The liver was free of metastasis and lymphadenopathy was not discovered. A total gastrectomy, omentectomy, and an end to end esophagojejunostomy were performed. The pathologic diagnosis determined a high grade leiomyosarcoma.

기종성 방광염을 동반한 기종성 신우신염 1예

김선두,김순제,이길도,김정수,김지훈,윤호상,송종오,문언수 대한노인병학회 2000 Annals of geriatric medicine and research Vol.4 No.3