용융금속 이송용 전자기 펌프의 유동해석 및 실험

최재호(Jae Ho Choi),임효재(Hyo Jae Lim),김창업(Chang Eob Kim),권정태(Jung Tae Kwon) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.5

This study aims at analyzing the flow characteristics of the electromagnetic pump using a linear induction motor (LIM) for transferring molten metals. The flow characteristics of the pump are simulated by magnetohydrodynamic(MHD) program. In this system, the LIM is used for transferring molten metal by electromagnetic force. The molten metal is treated as the secondary part of the LIM. Since the LIM produces an electromagnetic force in the duct, the molten metal can flow from the furnace to the reservoir. The flow characteristics of the pump are analyzed using MHD program for magnetic field of 0.1[T] in duct. In order to prove the analysis, we made a prototype electromagnetic pump using LIM.

접합부의 비선형 거동을 고려한 강뼈대 구조물의 고등해석과 최적설계

최세휴,박문호,송재호,임청권,Choi, Se Hyu,Park, Moon Ho,Song, Jae Ho,Lim, Cheong Kweon 한국강구조학회 2003 韓國鋼構造學會 論文集 Vol.15 No.6

The advanced analysis and optimal design of semi-rigid frame were presented. Advanced analysis can predict the combined nonlinear effects of connection, geometry, and material on the behavior and strength of semi-rigid frames. The Kishi-Chen power model was used to describe the nonlinear behavior of semi-rigid connections. Geometric nonlinearity was determined using stability functions. On the other hand, material nonlinearity was determined using the Column Research Council (CRC) tangent modulus and parabolic function. The direct search method proposed by Choi and Kim was used as optimization technique. The member with the largest unit value evaluated using the LRFD interaction equation was replaced one by one with an adjacent larger member selected from the database. The objective function was assumed as the weight of steel frame, with the constraint functions accounting for load-carrying capacities, deflections. inter-story drifts, and ductility requirement. Member sizes determined by the proposed method were compared with those derived using the conventional LRFD method. 본 논문에서는 접합부의 비선형을 고려한 강뼈대 구조물의 고등해석과 최적설계를 수행하였다. 고등해석은 접합부의 비선형, 기하학적 비선형 및 재료적 비선형을 고려한다. 접합부의 비선형은 Kishi와 Chen이 제안한 3가지 매개변수를 가지는 파워모델을 사용하여 고려하였다. 기하학적 비선형은 안정함수를 사용하여 고려하였으며, 재료적 비선형은 CRC 접선 탄성계수와 포물선 함수를 사용함으로서 고려하였다. 최적화 기법으로는 Choi와 Kim이 제안한 직접탐색법을 사용하였다. 직접탐색법은 LRFD의 상관방정식으로 계산된 값중에서 최대값을 가지는 부재의 크기를 단계별로 증가시키는 방법이다. 목적함수는 구조물의 중량을 사용하였으며, 제약조건식은 구조시스템의 하중-저항능력, 처짐, 층간 수평변위 및 연성요구 조건을 고려하였다. 제안된 방법에 의한 설계결과를 LRFD방법과 비교하였다.

심미성 수복재의 변연누출에 관한 비교 연구

임선희,임호남,최부병 慶熙大學校 齒科大學 1993 慶熙齒大論文集 Vol.15 No.1

This study evaluated the in vitro early marginal seal effectiveness in class V restorations of glass ionomer cement with or without dentin treatment, sandwich technique, and composite resin with several kinds of dentin bonding agents. The preparations were as uniformly as possible, with depth 1.5 mm, size 4 X 3mm. The one kind of glass ionomer cement for each type, 40% polyacrylic acid for dentin treatment, one kind of composite resin and three commercial dentin bonding agents were tested. Four groups were restored with only glass ionomer cement to evaluate the effect of dentin treatment and the type of glass ionomer on marginal leakage. Two groups were filled with composite resin with glass ionomer base by means of sandwich technique. And three groups were restored wih three commercial dentin bonding agent(Gluma�, Scotchbond 2�, and Tenure) and composite resin. The one that was filled with composite resin without use of dentin bonding agent was used as control group. Ten experimental groups including control group were established and each group had ten cavities. Eight of ten cavities of each group were used for marginal leakage test and two of ten, for investigation of marginal gap. Immediately after being restored, all of specimens were thermocycled 100 times through water bath of 5 ± It and 55 ± It for 38 sec in each bath. Then, marginal leakage of them were estimated by dye penetration method and scanning electron micrographs were taken to evaluate the marginal gap between dentin and restorations at X 1,000 magnification. On the summary of this study, the conclusions were as follows 1. Generally, more marginal leakage at the gingival margins was investigated than at the occlusal margin. While the groups filled with composite resin with dentin bonding agents showed less marginal leakage at occlusal margin, the groups restored with glass ionomer cement had the lower marginal leakage score at gingival margin. 2 When glass ionomer/composite resin sandwich restorations were compared with other restorations, they had least margial leakage at gingival margin. 3. Types of glass ionomer cement and dentin treatment did not affect on the marginal leakage at occlusal margin. At gingival margin, marginal leakage of light curing glass ionomer cement with dentin treat-merit showed significantly higher marginal leakage and wider marginal gap was seen in light curing glass ionomer cement than in chemical curing glass ionomer cement. 4. Though Tenure� exibited significantly less marginal leakage than Gluma� and Scotchbond 20, all of three dentin bonding agents seldom made wide marginal gap equally.

니켈담지촉매의 제조과정에서 액상산화의 효과

최재석,임태훈,홍성안,이호인 한국공업화학회 2004 응용화학 Vol.8 No.1

The deactivation of reforming catalyst in the DIR-MCFC was reported to be affected by dispersion, loading amounts, kind of support and so on. In this research, we checked the resistivities of catalysts prepared by the different methods, and examined the effect of liquid phase oxidation. The oxidized catalyst in a liquid phase showed the increased activity and dispersion even though the nickel species was supported by deposition-precipitation method. In order to investigate the role of the oxidation, TGA, TPR and XRD analyses were conducted. The increase in activity was ascribed to the strong metal-support interaction which was induced by liquidphase oxidation.

Starter 및 멸치액젓 첨가가 김치양념 및 겉절이 김치의 품질에 미치는 영향

최택권,박소희,유진현,임호수,조재선,황성연 한국식생활문화학회 2003 韓國食生活文化學會誌 Vol.18 No.2

양념에 Leu. mesenteroides, Lac plantarum의 젖산균과 멸치액젓 첨가가 김치 양념의 대장균군 제어, 속성촉진여부 및 관능적 특성에 미치는 영향을 조사하였다. Leu. mesenteroides과 젓갈을 첨가한 경우 초기 숙성이 촉진되나 후기 산패는 완만하였으며 Lac. plantarum의 첨가시에는 초기 숙성에는 큰 차이가 없고 후기 산패가 현저하게 진행되었다. 대장균군은 산도 0.80% 이상에서 사멸되었는데 leu. mesenteroides의 경우가 숙성이 촉진되어 보다 신속히 사멸시켰다. 총균수와 젖산균수는 초기에 starter 첨가구는 10^6CFU/mL 정도인데 반해서 starter를 첨가하지 않은 않은 처리구에서 총균수는 10^6CFU/mL , 젖산균수가 10^4CFU/mL 이었고 숙성 후에는 첨가균이 높은 수준을 유지하였다. 하지만 대체적으로 스타터의 첨가가 숙성 및 대장균에 크게 영향을 주지 못하는 경향으로 동일하게 나왔다. 관능적 특성에서는 Leu. mesenteroides 첨가구가 Lac. plantarum의 경우보다 우수하였다. 한편, 시판 겉절이 김치는 산도가 0.09~0.18%, ph 5.46~5.89, 총균수 2.2×10^6~3.1×10^7CFU/mL, 젖산균수는 2.1×10^4~6.6×10^5CFU/mL, 대장균수는 1.8×10^4~7.1×10^5CFU/mL, 염분 1.89%~2.51%으로 스타터 첨가 겉절이에 비해 ph와 염도를 제외한 품질 특성에서 전반적으로 낮은 값을 나타냈다. This study was performed in order to investigate the effect of Leuconostoc mesenteroides, Lactobacillus plantarum and salt fermented anchovy extracts on Kimchi sauce. The sauce was fermented more rapidly by addition of Leu. mesenteroids or salt fermented anchovy extracts on the early fermentation stage than the control, but it was fermented slowly on the late fermentation stage. When L. plantarum was added to the Kimchi on the early fermentation stage, the acidity of Kimchi didn't show a significant difference from the control, but acidity was remarkably increased on the late stage. Coliform group was disappeared when acidity of sauce was higher than 0.8% during fermentation. It was controlled by Leu. mesenteroides but not by L. plantarum. Total count and lactic acid bacterial count of the sauces with starter were 6.30×10^6~1.0×10^7 CFU/mL and 1.04~2.04×10^6 CFU/mL, respectively, but those of the control sauce were 10^6 CFU/mL and 10^4 CFU/mL, respectively. Those count of the sauce with starter were higher than those of the control sauce on the later stage of fermentation. Organoleptic quality of the sauce with Leu. mesenteroides was superior to that with L. plantarum.

어린 브리티쉬 숏헤어 고양이에서 발생한 비대성심근병증

임수정,이선희,손선호,최호정,송근호 忠南大學校 獸醫科大學 附設 動物醫科學硏究所 2008 動物醫科學硏究誌 Vol.15 No.1

A l0-month-old, neutered male, British shorthair cat was referred to the Veterinary Medical Teaching Hospital of Chungnam National University with the history of tachypnea, anorexia and depression which onset were two days ago. On physical examination, increased respiratory rate and no murmur were found. A complete blood count indicated thrombocytosis. Results from a serum biochemical profile demonstrated elevations in CK, ALP, BUN and Ca, and decreases in sodium, potassium and chloride. Thoracic radiographs revealed patchy interstitial opacity increase and left atrium enlargement. Echocardiographs showed the evidences of hypertrophic cardiomyopathy which were hypertrophy of diastolic interventricular septum and left ventricular free wall. Other findings on echocardiography were the reverse E:A ratio(tranmitra1 inflow pattern) and absence of systolic anterior motion of mitral valve. Electrocardiographs demonstrated wide P and R wave, which mean left atrium enlargement and left bundle branch block, respectively. Medications including furosemide (2mg/kg), enalapril (0.25mg/kg), and spironolactone (1mg/kg) were prescribed twice a day and orally. Client education about exercise restriction and possibility of aggressive progress was given. Clinical signs suggestive of thromboembolism were developed on 6th day after showing tachypnea; right forelimb lameness, bilateral hindlimb lameness, loss of femoral pulse and severe pain. After all, euthanasia was performed at local animal hospital, according to the owner's request.

수증기 개질반응용 니켈촉매에 첨가된 리튬의 효과

최재석,윤정숙,임태훈,홍성안,이호인 한국공업화학회 2005 응용화학 Vol.9 No.1

In the direct internal reforming type molten carbonate fuel cell, alkali carbonates used as electrolyte in the cell are transported to reforming catalyst of which activity drastically decreases. In our previous work, the deactivation of the nickel catalyst was studied with increasing the amount of added lithium. Unexpectedly, the increase of activity was observed with a small amount of lithium less than 1wt%. The results of TPR, XRD and chemisorption showed no significant difference between the fresh catalyst and the Li-added one, implying that lithium did not cause the change of morphological property of the supported nickel. To elucidate the effect of lithium the methanation of CO was applied to the catalysts, which was considered as the reverse reaction of the key elementary step of methane steam reforming. It can be seen by an online mass spectrometer that the small injection of CO/H₂ mixture into the Li-added catalyst reactor at 650 ℃ showed the longer tail of produced methane than into the fresh one. The delay should be originated from the effect of lithium, which determined the overall rate on the Li-added catalyst.

위암에서 근치적 절제술 후 전이 림프절 수가 예후에 미치는 영향

임호영,최진혁,김현수,남동기,김효철 아주대학교 의과학연구소 1998 아주의학 Vol.3 No.1

Gastric cancer is the most common cause of cancer death in Korea, and the most important prognostic factor for patients with gastric cancer is the extent of TNM stage. Among TNM staging system, lymph node involvement (N) has been recognized as one of the significant prognostic indicators after curative resection. Recently, nodal stage of new AJCC TNM staging system has changed its emphasis on the location of metastatic lymph nodes to the number of metastatic lymph nodes. Thus, we attempted to analyze the survival difference based on the number of metastatic lymph nodes after curative resection of gastric cancer. Two hundred and forty two patients of curatively resected gastric cancer were retrospectively studied to identify the number of metastatic lymph nodes to influence prognosis. The following results were obtained. The results showed that there was a significant difference in the survival rate between the patients with 0-2 metastatic lymph nodes and those with ≥3 metastatic lymph nodes in adjuvant chemotherapy (FA) group (DFS; 36.7% vs. 23.4%, OS; 38.3% vs. 26.0%). In adjuvant chemoimmunotherapy (FA+poly-AU) group, there was a significant difference in the overall survival between the patients with 0∼2 metastatic lymph nodes and those with ≥ 3 metastatic lymph nodes(70.1% vs. 47.4%). The present report demonstrates the prognostic importance of the number of metastatic lymph nodes in gastric cancer after curative resection and a necessity of further evaluation of current nodal stage.

건조된 한약재의 유전자 분석 가능성 연구

崔湖榮,任德彬 대한본초학회 2001 大韓本草學會誌 Vol.16 No.1

The isolation of DNA from crude drug has been described by numerous authors, each contributing a different method to overcome the problems that arise when extracting DNA. Fresh of frozen tissue is usually used as a source of DNA for PCR and RAPD analysis. A SDS method for rapid purification of DNA from variety of herbal crude drug, extracting from samples as small as 1㎎, has been optimized. I reached the following conclusion. The yield of DNA was declined after 3 and 4 days drying at 60℃. However, the DNA isolated from all sample at 60℃ in oven was suitable for analysis with random 10-mer primer as the primer. Similar results were obtained with crude drug Angelicae Gigantis Radix from the different drying time. I think that this result can not only be used as a way to discriminate crude drug but it can be also utilized to control the quality of crude drug and the distribution channel in the future.

運動選手의 身體構成과 體型 및 最大有酸素性 能力에 關한 縱斷的 硏究 : 蹴球選手를 中心으로 Emphasised on soccer Players

林相鶴,金豪敏,崔成根,韓泰龍 서울市立大學校 1989 論文集 Vol.23 No.-

This study attempts to find the change and the relationship of body composition somatotype and maximum aerobic power according to the age on the based of result of the survey performed to 69 subjects who attended in the K college, D high school, K middle school. The result were as follows : 1. The percent of fat of all the subjcets was lower than that of ordinary people. 2. Somatotype of subjects was higher mesomorph and lower endomorph. 3. Maximum oxygen uptake was increasing and maximum oxygen uptake per kilogram of body weight was decreasing according to growth. 4. Endomorph and maximum oxygen uptake was sure to have certain correlation.