• Structural Engineering and Mechanics
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• 제68권2호
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• pp.227-235
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• 2018

Cables are the main load-bearing members of prestressed structure and other tensegrity structures. Based on the static equilibrium principle, a new cable force identification method considering cable flexural rigidity is proposed. Its computational formula is derived and the strategy to solve its implicit formula is introduced as well. In order to improve the reliability and practicality of this method, the influence of the cable flexural rigidity on cable force identification accuracy is also investigated. Through cable force identification experiments, the relationships among certain parameters including jacking force, jacking displacement, initial cable force, and sectional area (flexural rigidity) are studied. The results show that the cable force calculated by the proposed method considering flexural rigidity is in good agreement with the finite element results and experimental results. The proposed method with high computational accuracy and resolution efficiency can avoid the influences of the boundary condition and the length of the cable on calculation accuracy and is proven to be conveniently applied to cable force identification in practice.

• Steel and Composite Structures
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• 제29권1호
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• pp.77-90
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• 2018

This paper presents a combined numerical, experimental, and theoretical study on the behavior of the concrete-filled double circular steel tubular (CFDT) stub columns under axial compressive loading. Four groups of stub column specimens were tested in this study to find out the effects of the concrete strength, steel ratio and diameter ratio on the mechanical behavior of CFDT stub columns. Nonlinear finite element (FE) models were also established to study the stresses of different components in the CFDT stub columns. The change of axial and transverse stresses in the internal and external steel tubes, as well as the change of axial stress in the concrete sandwich and concrete core, respectively, was thoroughly investigated for different CFDT stub columns with the same steel ratio. The influence of inner-to-outer diameter ratio and steel ratio on the ultimate bearing capacity of CFDT stub columns was identified, and a reasonable section configuration with proper inner-to-outer diameter ratio and steel ratio was proposed. Furthermore, a practical formula for predicting the ultimate bearing capacity was proposed based on the ultimate equilibrium principle. The predicted results showed satisfactory agreement with both experimental and numerical results, indicating that the proposed formula is applicable for design purposes.

• 대한한의학방제학회지
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• 제13권1호
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• pp.145-159
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• 2005

Objective : Juglandis Semen has a function that to invigorate the lung and kidney. And It is commonly used as a supporting agent in the treatment of coughing and bronchitis. This study was performed to investigate the effect of oral administration of Juglandis Semen Extract (JSE) against the experimental asthma induced by ovalbumin. Methods : Asthma was induced to Balb/c mouse by i.p. injection and aerosol immunization with ovalbumin. It was observed the change of the cell number in the BAL fluid. Concentrations of IL-4, IL-5 in splenoc yte were assessed by ELISA, IgG and IgE from serum were calculated by same method. Results : 1. Number of macrophage in BAL fluid was significantly decreased in JSE group compared with control group, but not eosinophil and lymphocyte. 2. Levels of IgG and IgE in serum were significantly decreased in JSE group compared with control group, respectively. 3. Concentration of IL-4 in culture supernatant of splenocyte was significantly decreased in JSE group compared with control group, but there was no significant in IL-5. Conclusion : We found that the effect of JSE extract in asthma was implicated in reduction of IL4released from Th2 cell, and decreases of IgG and IgE from plasma cell. These findings suggest that JSE can produce anti-asthmatic effect, which may play a role in allergen-induced asthma therapy.

• 대한한의학방제학회지
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• 제14권2호
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• pp.57-66
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• 2006

Objectives : The objective of this study is to observe the effect of Saryuktangkamibang, Saryuktang with Liriopis Tuber, Lycii Fructus, Schizandrae Fructus, and Bombyx Batryticatus, on the experimental diabetes. Methods : In order to induce diabetes experimentally, injected streptozotocin to the vein in the tail of rats and then treated oral administration of Saryuktangkamibang water extracts. In the measurement of the variation levels of glucose, ALP, creatinine, and BUN concentration for each concentration levels for serum (0.2g/100g, 0.4g/l00g, 0.6g/100g), concentration level of glucose significantly decreased in 0.4g/l00g concentration level of Saryuktangkamibang. With this 0.4g/l00g concentration level of Saryuktangkamibang, the following conclusion was derived from the measurement of the serum levels of glucose. ALP, AST, ALT, creatinine, and BUN concentration for the injection of each 4th, 11th, and 18th day. Results : 1. In the measurement for each concentrations, the glucose concentration level in the serum significantly decreased on the 9th day in the Saryuktangkamibang-dosed group. 2. The creatinine and BUN concentration level in the serum significantly decreased on the 9th day in the Saryuktangkamibang-dosed group to which 0.6g/100g injected. 3. In the measurement for each dosage dates, the glucose concentration level in the serum significantly decreased on the 11th day in the Saryuktangkamibang-dosed group to which 0.6g/100g injected. 4. The AST concentration level in the serum significantly decreased on the 11th day in the Saryuktangkamibang-dosed group. Conclusion : Saryuktangkamibang, Saruktang with Liriopis Tuber, Lycii Fructus, Schizandrae Fructus, and Bombyx Batryticatus, has an effect of hypoglycemia, with no hepato-renal dysfunction. For the experimental results above, in that nephrotoxicity significantly decreased on the 0.6g/100g concentration, another research such as study for effect in other ranges and study for effect of dosage term except the concentration range of this study is necessary. Also dosage of appropriate concentration of Saryuktangkamibang is thought to provide valuable aid to cure on diabetes.

• 대한한의학방제학회지
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• 제11권1호
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• pp.129-149
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• 2003

Liver is an important target of the toxicity of drugs, xenobiotics and oxidative stress. Acetaminophen pverdose causes acute liver injury in both humans and animals. This study was performed to observe the effect of sachunwhan and its component groups on recovery of hepatoxicity in acetaminophen treated rats. The experimental group was divided into 4 groups: sachungwhan(SC), samultang group(SC-1: 當歸, 川芎), chungyul group(SC-2: 龍膽草, 大黃, 梔子), and haepyo group(SC-3:羌活, 防風). Under the same condition Normal group was fed basal diet and water; Control group was injected acetaminophen and fed basal diet for 2 weeks; Experimental groups were injected acetaminophen and fed each extracts for 2 weeks respectively. The results were obtained as follows: 1. In the study on antioxidative defense system in vivo, SC reduced the amount of lipid peroxide in both serum and liver and showed activity on antioxidative enzymes such as catalase, glutathion. Other groups had effect only on glutathion. 2. In the study on hepatotoxicity(GOT, GPT, ${\gamma}$-GTP, ALP, LDH, Bilirubin), SC had a significant effect on recovery of hepatoxicity in acetaminophen treated rats. Other groups had no effect except SC-1 having effect on ${\gamma}$-GTP. As results shown, only Sachungwhan(SC) has significant effects on recovery of hepatoxicity and antioxidative defense system in vivo. These results suggest that Sachungwhan(SC) made antioxidative defense system active and it seemed to be very important to its effect on recovery of hepatoxicity. In the other hand, Component groups had no effect on recoverv of hepatoxicity and antioxidative defense system in vivo. This was thought that component drugs' cooperative synergy effect would be important to Sachungwhan(SC)'s effects mentioned in this paper.

• 대한한의학방제학회지
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• 제19권2호
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• pp.11-22
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• 2011

Objectives : Hwangyeonhaedok-tang(HHDT) has been traditionally used for various clinical symptoms associated with gastrointestinal disorder, cardiovascular diseases, and inflammation in the Oriental medicine. However, little is known for antioxidant and anti-inflammatory effects of HHDT on dextran-sulfate sodium(DSS)-induced colitis in mice. Methods : In this study, we investigated an antioxidant and anti-inflammatory effects of HHDT on DSS-induced colitis in mice. An experimental colitis was induced by daily treatment with 5% DSS. HHDT was orally administrated the various concentrations(25-100 mg/kg, body weight/day) for 7 days with one time per day. Results : HHDT reduced significantly clinical sign of DSS-induced colitis, including body weight loss, shorten colon length, disease activity index(DAI), and histological colon injury. HHDT also inhibited significantly serum NO and prostaglandine $E_2(PGE_2)$ productions in DSS-induced colitis mice. Furthermore, HDDT increased significantly an superoxide anion(SOD), catalase, and glutathione peroxidase(GPx) activity of the colon tissue in DSS-induced colitis mice. Conclusions : These results suggest that HHDT administration could reduce significantly the clinical signs and inflammatory mediators, and increase antioxidant activity in DSS-induced colitis model mice and is a good candidate for further evaluation as an effective anti-ulcerative agent.

• 대한한의학방제학회지
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• 제17권2호
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• pp.85-98
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• 2009

The fruits of Schisandra chinensis and Prunus mume have been traditionally used in the Oriental countries as an astringent against diarrhea and abdominal pain, a protectant for liver disease, an antimicrobial, and a blood tonic. However, little is known about the extract of Schizandrae Fructus and Mume Fructus (SMF-Ex) on dextran-sulfate sodium (DSS)-induced colitis in mice. In this study, we investigated the protective effects of SMF-Ex on DSS-induced colitis in mice. An experimental colitis was induced by daily treatment with 5% DSS. SMF-Ex was orally administrated the single dose (80 mg/kg, body weight/day) for 7 days with one time per day. SMF-Ex reduced significantly clinical sign of DSS-induced colitis, including body weight loss, shorten colon length, increased disease activity index (DAI), and histological colon injury. SMF-Ex also inhibited significantly nitric oxide (NO) and prostaglandine $E_2$ ($PGE_2$) productions in DSS-induced colitis mice. Furthermore, SMF-Ex increased significantly an superoxide anion (SOD), catalase, and glutathione peroxidase (Gpx) activity of the colon tissue in DSS-induced colitis mice. These results suggest that SMF-Ex administration could reduce significantly the clinical signs and inflammatory mediators, and increase antioxidant activity in DSS-induced colitis model mice and is a good candidate for further evaluation as an effective anti-ulcerative agent.

• 대한한의학방제학회지
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• 제16권2호
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• pp.171-182
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• 2008

The aqueous extract of Schisandra chinensis, Evodia rutaecarpa and meal (SEM-Ex) has been traditionally used in the Oriental countries as an astringent. However, little is known about the effects of aqueous extract of SEM-Ex on dextran-sulfate sodium (DSS)-induced colitis in mice. In this study, we investigated the protective effects of SEM-Ex on DSS-induced colitis in mice. An experimental colitis was induced by daily treatment with 5% DSS. SEM-Ex was orally administered from day 2 of DSS treatment in the different dose (10-50 mg/kg body weight). SEM-Ex reduced significantly clinical sign of DSS-induced colitis, including body weight loss, shorten colon length, increased disease activity index (DAI), and histological colon injury. Moreover, SEM-Ex suppressed significantly not only the serum haptoglobin levels and the activities of myeloperoxidase (MPO), but also the colon tissue expression levels of monocyte chemoattractant protein-1 (MCP-1) in DSS-induced mice. In contrast, SEM-Ex increased significantly the colon tissue expression levels of granular colony stimulating factor (G-CSF) well known as anti-inflammatory cytokine. These results suggest that SEM-Ex administration could reduce significantly the clinical signs and regulate of chemokine and anti-inflammatory cytokine in DSS-induced model mice. Therefore, these properties may contribute to the strong anti-ulcerative colitis (UC) response effect of SEM-Ex.

• 대한조선학회논문집
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• 제53권1호
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• pp.62-68
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• 2016

A simple calculation tool for added resistance in waves is developed to utilize for initial design or embedded module for navigation support system. In order to select an appropriate calculation method for added resistance in waves, three methods (drift method, integrated pressure method, radiated energy method) based on strip method are applied to Wigley I and KVLCC2. The methods for added resistance in waves give the underestimated results because it is difficult to consider nonlinear effects due to reflected wave. We apply asymptotic (Faltinsen's method) and empirical formula (NMRI's method) to improve the accuracy for short wave length region. In comparison with experimental results, the combination of radiated energy method and short wave correction method of NMRI is the most reasonable. However, a simple sum of results calculated by two methods gives rise to the overestimation of added resistance for short wave length region because added resistance of radiated energy method exits in total reflection region. To overcome this problem, modified radiated energy method is proposed using correction coefficient defined by reflection coefficient of NMRI's method. Finally, added resistance in regular waves is composed of added resistance of modified radiated energy method and that of short wave correction method of NMRI. Estimated added resistance in regular waves is validated by comparison with experimental results of other research groups.

• 한국농공학회지
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• 제29권4호
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• pp.93-105
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• 1987

This Study was carried out at the experimental Plot of Kang-Weon Province, Institute of Agriculture experiment, to find out Irrigation Water requirement and suitable calculating formula of evapotranspiration on Spreading Varieties of rice plant such as Seul Oak, Bokkwang and Teaback in Chuncheon Area. The evapotranspiration, infiltration, and consumptive use of water were measured by Micro Lysimeter for four years from '86yr. Also, yield of rice was investigated during same period. With the Kc Value taken from experimental value, evapotranspiration was calculated by methods of Blaney & criddle, Penman, Hargreaves and Thornthwaite by Computer using meteorological data in Chuncheon Area for twenty one yrs from '66yr to '86yr. All analyses were conducted based on average value of experiment for four years and the results are summarized as follows : 1) The yield by varieties through this experiment showed 1.06 times in Seul Oak, 1.94 times in Bokkwang and 1.89 times in Teaback more than Standard Yield. 2) The consumptive use of water including infiltration were 1.068.4mm in Seul Oak, 1,102. 6mm in Bokkwang and 1,195.6mm in Teaback 3) The evapotranspiration by Actual measurement presented 520.lmm in Seul Oak, 540.lmm in Bokkwang and 598.4mm in Teaback 4)The ratio of evapotranspiration and infiltration over Panevaporation showed 1.2 to 1.4. 5) The irrigation water reguirement by water balance were shown to be irrigated more than 584 mm / yr in average during 21 years from '66yr to '86yr for all Varieties and those for loyr frequency 693 mm in Seul Oak, 712 mm in Bokkwang and 728 mm in Teaback respectively. 6) Crop Coefficient (Ke Value) of the tested rice plant during the period were shown as Table 10. 7) Penman Method was the formula the most close to experiment Value among four different methods of Blaney & Griddle Penman, Hargreaves, and Thornthwaite.