• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.104-108
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• 2000

Drilling Jig is the device according to industrial demand for multi manufacturing products on the growing at alarming rate. In the field of design and making for machine tool working, welding, assembling with jig and fixture for mass production is a specific division. In order to prevent the production defects the optimum design of product, fig and fixture putting in the field is very significant manufacturing method. They require analysis of many kinds of important factors, theory and practice of machine tool operating process and its phenomena, jig & fixture structure, machining condition for tool making tool materials, heat treatment of jig & fixture components, know-how and so on. In this study we designed and constructed a drilling jig of mass production and performed tryout under the Auto CAD, database, and window environment. Especially Part1 of this study is reveals with the analysis of part drawing, jig planning, jig design etc.

• Korean Journal of Computational Design and Engineering
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• v.3 no.1
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• pp.1-14
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• 1998

This paper introduces non-manifold offsetting operations, which add or remove a uniform thickness from a given non-manifold model. Since these operations can be applied to not only solids but also wireframe or sheet objects, they are potentially useful for pipeline modeling, sheet metal and plastic part modeling, tolerance analysis, clearance checking, constant-radius rounding and filleting of solids, converting of abstracted models to solids, HC too1 path generation and so on. This paper describes mathematical properties and algorithms for non-manifold offsetting. In this algorithm, a sufficient set of tentative faces are generated first by offsetting all or a subset of the vertices, edges and faces of the non-manifold model. And then they are merged into a model using the Boolean operations. Finally topological entities which are within offset distance are removed. The partially modified offsetting algorithms for wireframes or sheets are also discussed in order to provide more practical offset models.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.11 no.1
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• pp.1-11
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• 2008

Comprehensive understanding of the natural course of chronic hepatitis B virus (HBV) infection is mandatory for the management and treatment of chronic hepatitis B, of which the natural course consists of immune tolerance, immune clearance, inactive carrier state, and reactivation phase. Evidence based medical approach is essential for the management of HBV carriers and treatment of active hepatitis to decrease risks of liver cirrhosis and hepatocellular carcinoma as well as to increase survival. In addition, education of patients or their parents are required to achieve a better therapeutic outcome and to prevent unconfirmed alternative medicine and anecdotal approaches.

• Korean Journal of Pharmacognosy
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• v.31 no.2
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• pp.163-167
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• 2000

Cordyceps is reputed for its broad biological activities and as a tonic for replenishing vital function in Chinese traditional medicines. As an attempt to obtain fundamental data for the development of a new type Cordyceps, the effects of the fruiting bodies of cultivated fungus of Paecilomyces japonica grown on silkworm larvae on hyperglycemia induced by streptozotocin(STZ) and by epinephrine in rats and in mice as well as on immunological functions in mice were investigated. The 70% methanol extract of the fungus, when administered orally at 100 and 300 mg/kg in STZ-induced hyperglycemic rats, caused a significant decrease in blood glucose level 3hr after sample treatments. The methanol extract, when administered p.o. at the same dose levels in epinephrine-induced hyperglycemic mice, also caused a significant decrease in serum glucose levels as well as a significant reversal of the liver glycogen contents suggesting its hypoglycemic activity might be due to glycogen breakdown in the liver. Treatment of normoglycaemic mice with the methanol extract of the fungus exhibited a significant glucose tolerance up to 3hr after oral glucose load(2.0 g/kg). The methanol extract also showed immuno-stimulating activity as measured by carbon clearance in mice and a significant antifatigue effect as measured by weight loaded forced swimming performance in mice.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.3
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• pp.127-134
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• 2018

Electric transmission towers are facilities to transport electrical power from a plant to an electrical substation. The towers are connected using power lines that are installed with a proper sag by loosening the cable to lower the tension and to secure the sufficient clearance from the ground or nearby objects. The power line sag may extend over the tolerance due to the weather such as strong winds, temperature changes, and a heavy snowfall. Therefore the periodical mapping of the power lines is required but the poor accessibility to the power lines limit the work because most power lines are placed at the mountain area. In addition, the manual mapping of the power lines is also time-consuming either using the terrestrial surveying or the aerial surveying. Therefore we utilized multiple overlapping images acquired from a low-cost drone to automatically reconstruct the power lines in the object space. Two overlapping images are selected for epipolar image resampling, followed by the line extraction for the resampled images and the redundant images. The extracted lines from the epipolar images are matched together and reconstructed for the power lines primitive that are noisy because of the multiple line matches. They are filtered using the extracted line information from the redundant images for final power lines points. The experiment result showed that the proposed method successfully generated parabolic curves of power lines by interpolating the power lines points though the line extraction and reconstruction were not complete in some part due to the lack of the image contrast.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.6
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• pp.1039-1046
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• 2007

This paper presents the analysis for power consumption, mechanical vibration and acoustic noise characteristics of the Coreless and Slotless Brushless DC motor in Digital Lightening Processor(DLP) Motor with the Air-Dynamic Bearing. The Coreless BLDC motor has not the stator yoke as well as the stator slot to remove the unbalance force by the interaction between the stator yoke and Air-Dynamic Bearing clearance. The assembling tolerance and the processing error make the air-gap difference between the magnet and the stator yoke .which occurs the unbalanced electro-magnetic force in the Slotless BLDC motor. It imposes the air-dynamic bearing on the disturbance force and makes the Air-Dynamic Bearing vibrated and noised. Also, The attractive force between the magnet and the silicon steel stator yoke increases the power consumption. In this paper, the power consumption, mechanical vibration and acoustic noise of the Coreless BLDC motor and the Slotless BLDC motor with the silicon steel stator yoke are simulated, analyzed, and tested using the manufactured proto-type motors with Air-Dynamic bearing. The simulated and tested results present that the Coreless BLDC motor without the silicon steel stator yoke has the lower mechanical vibration and noise ,and lower power consumption than the Slotless BLDC motor with the silicon steel stator yoke in Digital Lightening Processor Motor with Air-Dynamic Bearing.

• Journal of Chest Surgery
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• v.33 no.8
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• pp.605-612
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• 2000

Background: Ischemic preconditioning enhances the tolerance of myocardium against ischemia/reperfusion injury, with the enhancement of the recovery of post-ischemic myocardial function. This study was disigned to assess whether the protective effect of ischemic preconditioning could provide one additional hour of myocardial preservation in four hour myocardial ischemia in a rate heart. Material and method: Fourty four Spargue-Dawley rats, weighing 300~450gm, were divided into four groups. Group 1(n=7) and group 3(n=12) were subjected to 30 minutes of aerobic Langendorff perfusion without ischemic preconditioning and then preserved in saline solution at 2~4$^{\circ}C$ for 4 hours and 5 respectively. Group 2(n=7) and group 4(n=18) were perfused in the same way for 20 minutes, followed by 3 minutes of global mormothermic ischemia and 10 minutes of perfusion and then preserved in the same cold saline solution for 4 hours and 5 hours respectively. Heart rate, left ventricular developed pressure(LVDP), and coronary flow were measured at 15 minutes during perfusion as baseline. Spontaneous defibrillation time was measured after reperfusion. Heart rate, LVDP, and coronary flow were also recorded at 15 minutes, 30 minutes, and 45 minutes during reperfusion. Samples of the apical left ventricular wall were studied using a transmission electron microscope. Result: Time of spontaneous defibrillation(TSD) was significantly longer in group 4 than in group 1(p<0.001), and TSD in group 1 was significantly longer in comparision to that of group 2(p<0.05). Heart rate at 45 minutes was significantly higher in group 1 than in group 4(p<0.05). Heart rate at 15 min was significantly higher in group 2 than in group 1(p<0.001) and in group 4 than in group 3(p<0.05). Left ventricular developed pressure(LVDP) at 30 minutes and 45 minutes was higher in group 1 than in group 4(p<0.01), LVDP at 45 minutes was higher in group 4 than in group 3(p<0.05). Rate-pressure product(RPP) at 30 minutes and 45 minutes was higher in group 1 than in group 4(p<0.05). RPP at 15 minutes was higher in group 2 than in group 1(p<0.01). RPP at 30 minutes and 45 minutes was higher in group 4 than in group 3(p<0.05). Group 2 showed relatively less sarcoplasmic edema and less nuclear chromatin clearance than group 1. Group 4 showed less myocardial cell damage than group 3, group 4 showed less myocardial cell damage than group 3, group 4 showed more myocardial cell edema than group 1. Conclusion: Ischemic preconditioning enhanced the recovery of postischemic myocardial function after 4 hours and 5 hours preservation. However, it was not demonstrated that ischemic preconditioning could definitely provide one additional hour of myocardial preservation in four hour myocardial ischemia in a rat heart.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.295-301
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• 1993

Since Jan. 1991 a prospective randomized study for Stage III unresectable non small cell lung cancer (NSCLC) has been conducted to evaluate the response rate and tolerance of induction chemotherapy with MVP followed by hyperfractionated radiotherapy and evaluate the efficacy of maintenance chemotherapy in Asan Medical Center. All patients in this study were treated with hyperfractionated radiotherapy (120 cGy/fx BID, 6480 cGy/54 fx) following 3 cycles of induction chemotherapy, MVP (Mitomycin C 6 $mg/m^2,$ Vinblastin 6 $mg/m^2,$ Cisplatin 60 $mg/m^2$) and then the partial and complete responders from induction chemotherapy were randomized to 3 cycles of adjuvant MVP chemotherapy group and observation group. 48 patients were registered to this study until December 1992; among 48 patients 3 refused further treatment after induction chemotherapy and 6 received incomplete radiation therapy because of patient's refusal, 39 completed planned therapy. Twenty-three $(58\%)$ patients including 2 complete responders showed response from induction chemotherapy. Among the 21 patients who achieved a partial response after induction chemotherapy,1 patient rendered complete clearance of disease and 10 patients showed further regression of tumor following hyperfractionated radiotherapy. Remaining 10 patients showed stable disease or progression after radiotherapy. Of the sixteen patients judged to have stable disease or progression after induction chemotherapy, seven showed more than partial remission after radiotherapy but nine showed no response in spite of radiotherapy. Of the 39 patients who completed induction chemotherapy and radiotherapy, 25 patients $(64\%)$ including 3 complete responders showed more than partial remission. Nineteen patients were randomized after radio-therapy. Nine Patients were allocated to adjuvant chemotherapy group and 4/9 showed further regression of tumor after adjuvant chemotherapy. For the time being, there is no suggestion of a difference between the adjuvant chemotherapy group and observation group in distant metastasis rate and survival. Median survival time was 13 months. Actuarial survival rates at 6,12 and 18 months of 39 patients who completed this study were $84.6\%,\;53.7\%\;and\;40.3\%,$ respectively. The partial and complete responders from induction chemotherapy showed significantly better survival than non-responders (p=0.028). Incidence of radiation pneumonitis in this study group was less than that in historical control group inspite of induction chemotherapy. All patients tolerated hypertractionated radiotherapy without definite increase of acute complications compared with conventional radiotherapy group. The longer follow up is needed to evaluate the efficacies of induction and maintenance chemotherapy and survival advantage by hyperfractionated radiotherapy but authors are encouraged with an excellent tolerance, higher response rate and improvement of one year survival rate in patients of this study.