• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.8
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• pp.1195-1208
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• 1997

Bellows is a component in piping systems which absorbs mechanical deformation with flexibility. Its geometry is an axial symmetric shell which consists of two toroidal shells and one annular plate or conical shell. In order to analyze bellows, this study presents the finite element analysis using a conical frustum shell element. A finite element analysis is developed to analyze various bellows. The validity of the developed program is verified by the experimental results for axial and lateral stiffness. The formula for calculating the natural frequency of bellows is made by the simple beam theory. The formula for fatigue life is also derived by experiments. The shape optimal design problem is formulated using multiple objective optimization. The multiple objective functions are transformed to a scalar function by weighting factors. The stiffness, strength and specified stiffness are considered as the multiple objective function. The formulation has inequality constraints imposed on the fatigue limit, the natural frequencies, and the manufacturing conditions. Geometric parameters of bellows are the design variables. The recursive quadratic programming algorithm is selected to solve the problem. The results are compared to existing bellows, and the characteristics of bellows is investigated through optimal design process. The optimized shape of bellows is expected to give quite a good guideline to practical design.

• Journal of Korean Society of Steel Construction
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• v.19 no.6
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• pp.725-735
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• 2007

The local buckling strength and post-local buckling strength of thin steel plates in the steel-concrete composite column were evaluated by nonlinear finite element analyses. The proposed width-to-thickness limit ratio was based on elastic buckling analyses, in which the increased local buckling capacity of the plate due to the in-filled concrete was considered by the boundary conditions of the thin plate. Considering the initial imperfections and residual stresses, we determined the initial local buckling strength and post-local buckling strength of the thin plates with various width-to-thickness ratios. The formula to evaluate the compressive capacity of the steel-concrete composite column based on the effective width of the plate was proposed. For verification, values determined by the formula were compared with the experimental results.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.1
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• pp.109-117
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• 2011

It was calculated using empirical formulas for the weight of Tetrapod, which was a representative armor unit in the rubble mound breakwater in Korea. As the formulas were evaluated from a curve-fitting with the result of hydraulic test, the uncertainty of experimental error was included. Therefore, the neural network and M5' model tree were used to minimize the uncertainty and predicted the stability number of armor block. The index of agreement between the predicted and measured stability number was calculated to assess the degree of uncertainty for each model. While the neural network with the highest index of agreement have an excellent prediction capability, a significant disadvantage exists that general designers can not easily handle the method. However, although M5' model tree has a lower prediction capability than the neural network, the model tree is easily used by the designers because it has a good prediction capability compared with the existing empirical formula and can be used to propose the formulas like an empirical formula.

• Herbal Formula Science
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• v.6 no.1
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• pp.199-214
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• 1998

This study was performed to prove the antithrombotic effects of DoHongYeum fluid by way of experimental methods. The thrombosis was induced by injection of collagen the mixture (0.1ml/10g, 2mg/kg B.W)plus serotonin (5mg/kg B.W) into the caudal vein of rat, 2 hours after liquid extract of DoHongYeum was oral administration. The effect of the fluid of DoHongYeum was rxamined by the number of RBC and platelets, bleeding time, blood clotting time, death rate, platelet aggregation, plasmacoagulation factor activity, exvivo and fibrinolytic activity of englobulin fracture in the rats. The results were summerized as followings. 1. The number of RBC and platelets was significantly increased in DoHomeYeum group incomparison with the control group. 2. Bleeding time was significantly shortened in DHY group in comparison with the controlgroup. 3. Blood clotting time was significantly prolonged in DHY group in comparison with the control group. 4. The death rate of mouse was inhibited in DHY group in comparison with the control group. 5. The platelet aggregation was inhibited in DHY group in comparison with the control group. 6. The prothrombin time and activated partial thromboplastin time on the test of plasmacoagulation factor activity was prolonged but was not valuable in DHY group. 7. Fibrinogen lyses time of rat was reduced and lyses area was increased in DHY group incomparison with the control group. 8. Fibrinogen lyses time of rat in vitro assay was reduced in DHY group. From the above results, it was thought that the DoHongYeum could be applied effectively in the thrombosis.

• Herbal Formula Science
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• v.10 no.1
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• pp.81-92
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• 2002

This study was performed to observe the effect of hyulbuchukeo-tang and its component groups on recovery of hepatoxicity in alloxan treated rats. The experimental group was divided into 3 groups: hyulbuchukeo-tang(HCT) and its components groups, sayeok-san(H-sa) and dohong-samul-tang (H-do). The results were obtained as follows: 1. The level of Glucose was considerably reduced by HCT, H-sa, H-do with high significancy. 2. In the change of GOT activity, HCT and H-do were decreased with high significancy, H-do was decreased with some significancy. 3. In the change of GPT activity, HCT was decreased with high significancy, H-sa and H-do were decreased with some significancy. 4. In the change of ${\gamma}-GPT$ activity, HCT was decreased with high significancy, H-do was decreased with some significancy. 5. In the change of ALP activity. only HCT was decreased with some significancy. 6. In the change of LDH activity, HCT was decreased with high significancy, H-sa and H-do were decreased with some significancy. 7. In the change of bilirubin contents. only HCT was decreased with some significancy. As result, hyulbuchukeo-tang(HCT) has significant effects on recovery of hepatoxicity, and its components groups. sayeok-san(H-sa) and dohong-samul-tang(H-do) have some effects. It suggests that sayeok-san(H-sa) and dohong-samul-tang(H-do) have more effects on recovery of hepatoxicity in case of the combination of the two (that is hyulbuchukeo-tang) than in case of the separation.

• Herbal Formula Science
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• v.10 no.1
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• pp.73-80
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• 2002

We have examined the purgative effect of three Jechun-jun formulas in sprague dawley(SD) rat. Three jechun-jun formulas were Jechun-jun(Sample I ) and augmented Jechun-jun(Sample II) and augmented Jechun-jun add rhubarb(sample III ). We examined the amount and the humidity of feces in rat. The experimental animals were devided into four groups. as control group and three Jechun-jun (sample I, II, III). We administerd the water extract of sample I, II, III to rat per oral for 8days long. After every 24hours measured the amount of wet feces from rats in metabolic cage. Humidity rate of feces from rat was at first measure wet feces for 24hours (W) and measure dried feces (W1) and then we consider W-W1 as humidity. High humidity rate means constipation changes into moistening stool. The amount of wet feces and humidity rate of feces in rats were increased in sample I, II, III. Sample I has highest humidity rate of feces. so showed strong moistening effect. Sample II has mild effect in treating constipation. sample III has most amount of wet feces. in conclusion Jechun-jun has an effect of moistening stool. and augmented Jechun-jun add rhubarb has strong purgative effect.

• Herbal Formula Science
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• v.6 no.1
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• pp.157-173
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• 1998

The following study looked at the effects of Hyangsayukgunjatang and Hyangsayukgunjatang-ga-kyenegum, moryobun on gastric ulcers in rats. In the 1st experiment, ulcers were induced by method of shay's pylorus-ligated in rats. Subjects were administered 2 kinds of medicine, Hyangsayukgunjatang and Hyangsayukgunjatang-ga-kyenegum, moryobun, which were taken orally. The quantity of gastric juice secretion, total acidity of gastric juice, HCI secretion and serumgastrin content were measured and tissues of gastric mucosa epithelium were observed. 1. The quantity of gastric juice secretion in Hyangsayukgunjatang-treated and Hyangsayukgunjatang-ga-kyenegum, moryobun-treated groups showed significant decrease incomparision with the control group. 2. In relation to total acidity of gastric juice, only Hyangsayukgunjatang -treated groupshowed significant decrease in comparison with the control group. 3. HCI secretion of Hyangsayukgunjatang-treated and Hyangsayukgunjatang-ga-kyenegum, moryobun-treated groups showed significant decrease in comparision with the control group. 4. Content of serum gastrin, which were present in Hyangsayukgunjatang -treated and Hyangsayukgunjatang-ga-kyenegum, moryobun- treated groups showed significant decrease in comparision with the control group. 5. The degree of ulcer occurrence & parietal cell numbers and chief cell numbers of Hyangsayukgunjatang-treated and Hyangsayukgunjatang-ga-kyenegum, moryobun-treatedgroups, which were observed by macrographic & histologic method showed signicant decreasein comparison with the control group. Hyangsayukguniatang-treated group prooved to be increasingly effective. From above the experiment results it can be concluded that Hyangsayukgunjatang will be more clinical effective on curing gastric ulcers induced by method of Shay's pylorus-ligated rather than that of Hyangsayukgunjatang-ga-kyenegum, moryobun.

• Herbal Formula Science
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• v.23 no.1
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• pp.91-99
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• 2015

Objectives : Herba on lipid levels in serum and lipid accumulation in liver tissue in high fat diet-induced hyperlipidemic mice. Methods : Experimental groups were subdivided into four; Normal diet group (Nor), Hyperlipidemic mice (Con), Lysimachiae Herba water extract administered mice (LWE), Lysimachiae Herba methanol extract administered mice (LME). Thereafter the changes in body weight, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride, AST, ALT, fasting blood glucose in serum were measured. In addition histopathological changes in liver tissue was also observed. Results : Body weight, AST and ALT were not affected by the administration of water or methanol extracts of Lysimachiae Herba. However, methanol extracts of Lysimachiae Herba down regulated the total cholesterol and triglyceride in high fat diet - induced hyperlipidemic mice. Conclusions : In this study, results of total cholesterol and triglyceride showed significant effect in LME compared with LWE, but other results didn’t. Therefore, it is necessary to have more study of Lysimachiae Herba to apply hyperlipidemia.

• The Journal of Korean Medicine
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• v.26 no.2 s.62
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• pp.13-24
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• 2005

Objectives & methods; In order to evaluate the in vivo synergic effect of Mawhangyounpye-tang, a traditional poly-herbal formula used in the treatment of respiratory diseases in Korea, with the quinolone antibiotic ciprofloxacin (CPFX), the viable bacterial number and histopathological changes were monitored after experimental respiratory infection with Streptococcus Pneumoniae ATCC 6303. Results: 1. In CPFX groups, the viable bacterial numbers were significantly decreased compared to that of the control group, and were even more dramatically decreased in concomitant group treated with Mawhangyounpye-tang. 2. In the control group, severe infiltration of inflammatory cells, hemorrhage and hypertrophy of alveolar linings were demonstrated at microscopic levels. However, these abnormal histopathological changes were significantly decreased compared. to that of the control group in CPFX groups, and were even more dramatically decreased in concomitant groups treated with Mawhangyounpye-tang. 3. In CPFX groups, the LSA (Iuminal surface of alveoli $\%$) were significantly increased compared to that of the control group, and more dramatically in concomitant groups treated with Mawhangyounpye-tang. Conclusions: According to these results, it is considered that the in vivo antibacterial activity of CPFX against Streptococcus Pneumoniae ATCC 6303 infection of respiratory tract was dramatically increased by concomitant use of Mawhangyounpye-tang.

• Clinical and Experimental Pediatrics
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• v.53 no.5
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• pp.634-638
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• 2010

Purpose: In Kyung Hee East-West Neo Medical Center, Seoul, Korea, efforts to raise rooming-in care success rate have been undertaken since when the hospital was established in 2006. We intended to analyze our experience over the past 3 years of period and to discuss the advantages of rooming-in. Methods: We analyzed the rooming-in practice rate, failure rate, and the breast feeding rate. Subjects were 860 normal healthy neonates from June 2006 to June 2009. Results: Among these 860 cases, 83 babies were required separation out of rooming-in in the middle of the course. Among these 83 cases, 70 cases had to stop the course due to poor condition of babies and 13 cases due to maternal condition. 70 cases of infant's causes consist of 68 cases of NICU admission and 2 cases of poor feeding support. The other 13 cases of separation include refusal by maternal condition. Therefore the success rate of rooming-in for the last 3 years was 90.3%, that is 777 cases among the total 860 cases. The percentage of exclusive breast feeding was 64%, that of mixed feeding with breast and formula feeding was 25%, and formula feeding only was 11%. Conclusion: We experienced successful rooming-in care for the last 3 years. Nursery facilities should educate and encourage the advantages of rooming-in, including the good formation of attachment between mother and infant, emotional stability, protection from infection, and increased breast feeding rate so that rooming-in care can be fully established.