• 한국임상수의학회지
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• 제20권3호
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• pp.323-327
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• 2003

This study has been conducted to compare the efficacy of sodium carboxymethylcellulose (SCMC) and hyaluronic acid (HA) on prevention of adhesion after artificial wound was induced in intestine. 1 % SCMC and 0.3% HA solution and saline solution were respectively administered to abdominal cavity. Each of the three groups consists of 11 rats. The abdominal cavity of each rat was coated with 2 ml of the allocated solution just after the abdomen was cut open, and it was coated with each solution of 1 ml before abrasion were caused on the cecum, the ascending colon and the transverse colon. Then, an additional 1 ml solution was injected before the abdomen was closed. On day 14 after the operation, each adhesion formation was evaluated at the score of 0-4. The HA group and SCMC group showed significantly lower adhesion scores than control group in all regions(P< 0.05). The adhesion scores of ascending colon, transverse colon and no abrasion region of the viscera showed little difference between HA group and SCMC group(P< 0.05), but the effect of adhesion reduction showed higher tendency in the HA group than the SCMC. The adhesion score of the cecum was significantly lower in HA group than SCMC group(P< 0.05). In conclusion, the SCMC solution and HA solution were effective on prevention of abdominal adhesion resulting from the celiotomy. Among of them, the HA solution could be more effective on prevention of adhesion than SCMC solution.

• International Journal of Industrial Entomology and Biomaterials
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• 제33권2호
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• pp.144-148
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• 2016

Recently, silk sericin has been studied extensively for biomedical and cosmetic applications because of its unique properties, including UV resistance and wound healing ability. For use in applications, sericin is fabricated in various forms including films and gels. However, the mechanical properties of sericin are too weak. In this basic study on improving the mechanical properties of sericin, a silk sericin aqueous solution was separated into two layers by centrifugation. The solution viscosity, molecular conformation, and mechanical properties of each separation layer of the sericin were examined. Sericin from the lower layer had a higher solution viscosity and film mechanical properties (strength and strain) than that from the upper layer, implying that sericin from the lower layer had a higher molecular weight than that from the upper layer. The molecular conformation of the sericin films varied depending on the casting solvent. In aqueous solution, the sericin film from the lower layer showed a ${\beta}$-sheet conformation, whereas that from the upper layer displayed a random coil conformation. All the sericin films showed a highly ${\beta}$-sheet-crystallized state when cast in formic acid, regardless of the separation layer.

• 대한조선학회논문집
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• 제56권5호
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• pp.418-426
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• 2019

To derive a simplified analytic solution which can be utilized as a fundamental solution for the wave maker design, a segment of the wave board has been idealized as a submerged line segment in a two dimensional domain of a wave flume. The lower end of the line segment could be located at arbitrary depth of the wave flume and the upper end of the board could be also submerged to any depth from the free surface. The freely oscillating motion of the wave board is assumed to be defined by determining the condition of horizontal oscillation on both ends differently. The submerged wave board oscillating in horizontal direction could be specified by selecting the amplitude, frequency and the phase lag differently on lower and upper ends of the board. The simplified two dimensional wave generated by the wave board segment has been obtained by the first order perturbation method. It is found that the general solution of the freely oscillating wave board in two dimensional domain could be decomposed into the solution of flap motion with lower end hinge and swing motion with upper end hinge. The case study of the analytic solutions has been carried out to evaluate the effect on the wave height due to the difference of oscillation frequency, phase difference and variation of stroke between for the motion of both ends. It is found that the solution of the freely oscillating wave board could be utilized for the development of high performance wavemaker especially for irregular waves.

• 한국식품영양과학회지
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• 제44권10호
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• pp.1525-1530
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• 2015

본 연구는 전통 된장이 최근 혈전용해능력, 피부병, 혈관질환 예방, 면역강화, 항산화 효과, 항암 효과 등의 우수한 기능이 밝혀지고 있지만 식염 함량이 높다는 단점을 가지고 있어 이를 해결하기 위해 저염 된장 제조를 목적으로 염수 농도를 13, 14, 15, 16, 17, 18%로 하여 전통 된장을 제조한 후 수분 함량, 식염 함량, 아미노태 질소 함량, pH 및 적정산도, 환원당 함량을 분석하였으며, 관능평가 묘사분석을 통해 농도별 특성의 강도와 기호도를 측정하였다. 소금물 농도를 달리하여 된장을 제조하고 이화학적 분석을 실시한 결과 염수 농도가 높아질수록 수분 함량과 아미노태 질소 함량은 낮아지는 경향을 보였으나, 소금 함량과 환원당 함량은 염수의 농도가 높아질수록 높아지는 경향을 나타내었다. 각 처리구별 된장의 pH 값은 염수의 농도가 낮을수록 낮아지는 경향을 나타내었으나, 적정산도 값은 염수의 농도가 낮을수록 높아지는 경향을 나타내었다. 소금물 농도를 달리하여 된장을 제조하였을 때 정량묘사분석 결과 된장은 18%가 가장 높은 짠맛을 냈는데 15%, 16%, 17% 처리구가 18%와 짠맛에서 유의적 차이가 존재하지 않았다. 기호도 평가로 보면 된장은 17%와 18%가 유의적으로 가장 많이 선호되었다. 결론적으로 전통 된장은 된장 숙성 시작 3개월 후까지 결과를 측정한 바로는 물리화학적 특성이나 관능특성 강도 측면에서 유의차를 나타내지 않는 농도는 16% 이상의 염수로 된장을 제조하였을 때로 16%의 염수를 이용하여 전통 된장을 제조하는 것은 가능할 것으로 보인다. 그러나 기호도 평가 결과와 저장기간에 따른 변화를 고려하여야 할 것으로 판단된다.

• Journal of Chest Surgery
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• 제27권10호
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• pp.815-823
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• 1994

This study was undertaken to hemodynamically determine the differences of myocardial protective effect between crystalloid and blood cardioplegic solution. Twenty nine children undergoing cardiac operations due to cyanotic congenital heart diseases were randomized into two groups receiving crystalloid or blood cardioplegia. Cardiac indices and other hemodynamic datum were examined postoperatively. Although there was no statistical differences between groups, postoperative stroke volume indices and left ventricular stroke work indices were slightly better with blood cardioplegia. We also found that postoperative left atrial pressures[p=0.0003], central venous pressures[p=0.004], and heart rates[p=0.014] were significantly lower with blood cardioplegia. The fact that relatively lower ventricular preloads [left atrial pressure and central venous pressure] were required to provide adequate cardiac output in blood cardioplegia group suggested superior myocardial protective effect of blood cardioplegic solution.

• 한국경영과학회지
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• 제20권1호
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• pp.1-10
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• 1995

The purpose of this paper is to develop a method of the sensitivity analysis that can be applied to a non-tree solution of the minimum cost flow problem. First, we introduce two types of sensitivity analysis. A sensitivity analysis of Type 1a is the well known method applicable to a tree solution. However this method can not be applied to a non-tree solution. So we propose a sensitivity analysis of Type 2 that keeps solutions of upper bounds at upper bounds, those of lower bounds at lower bounds, and those of intermediate values at intermediate values. For the cost coefficient we present a method that the sensitivity analysis of Type 2 is solved by finding the shortest path. Besides we also show that the results of Type 2 and Type 1 are the same in a spanning tree solution. For the right-hand side constant or the capacity, the sensitivity analysis of Type 2 is solved by a simple calculation using arcs with intermediate values.

• Journal of Chest Surgery
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• 제21권6호
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• pp.979-983
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• 1988

Calcium channel blockers may prevent myocardial injury during cardioplegia and reperfusion. This study was done to evaluate the effects of diltiazem cardioplegia on myocardial protection during ischemic arrest and recovery of myocardial function after reperfusion. Four formulations of crystalloid cardioplegic solutions, GIK solution[group I, n=12], diltiazem[lug/ml GIK] in GIK solution[group II, n=7], ],diltiazem[2ug/ml GIK] in GIK solution[group III, n=6] and diltiazem[4ug/ml GIK] in GIK solution[group IV, n=6] were compared in isolated working rat heart subjected to a long period [2 hours] of hypothermic arrest with multi-dose infusion. Diltiazem cardioplegia[group II, III and IV]was found to be superior in nearly all aspects. Diltiazem cardioplegia showed faster recovery of regular rhythm and lower incidence of ventricular fibrillation than group I did. In comparing mechanical function in all experimental hearts, the mean postischemic recoveries of aortic flow, cardiac output, peak aortic pressure, stroke volume and stroke work[expressed as a percentage of its preischemic control] were significantly greater in group II, III and IV[diltiazem cardioplegia] than in group I. The infused amount of cardioplegic solution was more increased by the addition of diltiazem to GI K solution. [p < 0.01] Creatine kinase leakage tended to be lower in hearts receiving diltiazem cardioplegia, especially in group III and IV[p<0.05] than in those receiving GIK solution only[group I]. Diltiazem cardioplegia results in the increased flow of cardioplegic solution and the decreased ischemic injury of myocardium during ischemic arrest and the improved recovery of myocardial function after reperfusion, and a dose-response relation must be established before clinical use.

• 동아시아식생활학회지
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• 제9권3호
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• pp.356-362
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• 1999

Humans may lose considerable amounts of water and electrolytes from sweat during exercise in a hot climate. Optimal ingestion of fluid-replacement beverages may overcome an obstacle factor of exercise performance in the heat. This study was performed the comparison of heart rate and blood lactate between ingestion of Prunus mume solution and water solution during graded maximal exercise using bicycle ergometer in the heat(ambient temperature of 31-32$^{\circ}C$ and relative humidity of 50-55%). Ten healthy no-heat-acclimatized males participated in the study. Exercise duration until all-out of graded testing in the condition of Prunus mume solution ingestion(786.15$\pm$47.66s) was significantly higher(P＜0.05) than the condition of water ingestion. Heart rate at 4 min during graded testing and recovery phase in the condition of Prunus mume solution ingestion was significantly lower(P＜0.05) than the condition of water ingestion. Blood lactate concentration at 30min of recovery phase after graded maximal exercise in the condition of Prunus mume solution ingestion was significantly lower(P＜0.05) than the condition of water ingestion. Recovery rate of blood lactate concentration at 15 min and 30 min of recovery phase after grated maximal exercise in the condition of Prunus mume solution ingestion was significantly lower(P＜0.05) than the condition of water ingestion. Present results suggested that ingestion of Prunus mume solution showed the positive effects on the cardiorespiratory function and acid-base regulation as compared with ingestion of water during graded maximal exercise and recovery phase in hot environment.

• Ocean Systems Engineering
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• 제3권1호
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• pp.55-70
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• 2013

A composite breakwater with an upper horizontal porous plate and a lower rubble mound is proposed and studied in this work. By means of matched eigenfunction expansions, a semi-analytical solution is developed for analyzing the hydrodynamic performance of the breakwater. The semi-analytical solution is verified by known solutions for special cases and an independently developed multi-domain boundary element method solution. Numerical examples are given to examine the reflection, transmission and energy loss coefficients of the breakwater and the wave force acting on the horizontal porous plate. Some useful results are presented for engineering applications.

• 산업공학
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• 제7권3호
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• pp.193-199
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• 1994

The purpose of this paper is to develop a method of the sensitivity analysis that can be applicable to a degenerate tree solution of the minimum cost flow problem. First, we introduce two types of sensitivity analysis. A sensitivity analysis of Type 1 is the well known method applicable to a spanning tree solution. However, this method have some difficulties in case of being applied to a degenerate tree solution. So we propose a sensitivity analysis of Type 2 that keeps solutions of upper bounds remaining at upper bounds, those of lower bounds at lower bounds, and those of intermediate values at intermediate values. For the cost coefficient, we present a method that the sensitivity analysis of Type 2 is solved by using the method of a sensitivity analysis of Type 1. Besides we also show that the results of sensitivity analysis of Type 2 are union set of those of Type 1 sensitivity analysis. For the right-hand side constant or the capacity, we present a simple method for the sensitivity analysis of Type 2 which uses arcs with intermediate values.