• 한국산업융합학회 논문집
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• 제7권2호
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• pp.161-166
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• 2004

The impact factor of bridges is analyzed based on experimental data to examine the characteristics of the dynamic responses of bridges. The experimental impact factors are compared with the impact factor of Korean Highway Design Specification and Japan T-load in terms of the span length. According to the superstructural types of bridges, the variation of the impact factor is analyzed. When vehicles are passing on a bridge, the dynamic effect acts on the bridge impact factor more than at the time of design because of the velocity of vehicles, the surface roughness reduction due to the deterioration of the bridge deck pavement, and the disconnection of the bridge entrance and the expansion joint. Because the actual value is greater than the expected value at the time of design, the dynamic response of the bridge accelerates the deterioration of the bridge due to the accumulation of fatigue, and the bridge's life-time is shortened and can have an influence on the serviceability and safety of the bridge.

• Earthquakes and Structures
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• 제8권3호
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• pp.681-697
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• 2015

Iran as one of the countries located on the Alpine-Himalayan seismic belt has recently experienced a few number of catastrophic earthquakes. A well-known index of how buildings are affected by earthquakes is through assessment of probable Peak Ground Acceleration (PGA) and structures' response spectra. In this research, active faults around Kerman and Birjand, two major cities in eastern parts of Iran, have been considered. Seismic catalogues are gathered to categorize effects of surrounding faults on seismicity of the region. These catalogues were further refined with respect to time and space based on Knopoff-Gardner algorithm in order to increase statistical independency of events. Probabilistic Seismic Hazard Analysis (PSHA) has been estimated for each of cities regarding 50, 100, 200 and 500 years of structures' effective life-span. These results subsequently have been compared with Deterministic Seismic Hazard Analysis (DSHA). It has been observed that DSHA not necessarily suggests upper bound of PSHA results. Furthermore, based on spectral Ground Motion Prediction Equations (GMPEs), Uniform Hazard Spectra (UHS) and spectral acceleration were provided for 2% and 10% levels of probability of exceedance. The results show that increasing source-to-site distance leads to spectral acceleration reduction regarding each fault. In addition, the spectral acceleration rate of variation would increase if the source-to-site distance decreases.

• 산업기술연구
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• 제22권A호
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• pp.119-125
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• 2002

In Kwangjin industrial company, mill is operating for the foundry sand production at the rate of 25t/hr from quartzite. Foundry sands fall into four distinct categories: silica sand, lake sand, bank sand, and natural molding sand. Silica sand is a general term used to describe crushed, washed, graded, dried, and cooled clay-free sands. This study was conducted for the investigation of the foundry sand productivity and the life span of the hammer according to the material quality. The life time of hammer from several manufacturer were compared in order to find out the grinding efficiency of the various hammer material. In the result of tests, the life time of high-Mn hammer was 10.5 hours while that of high-Cr was 19.5 hours. The life time in case of typical worn shape hammers was about 12 hours and the average time of a blowhole hammer was about 6.5 hours.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.6-14
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• 2007

The objective of this research is to comparative LCA(life cycle assessment) between two different model of Electric Motor Unit(EMU).the environmental impact of Aluminum body Electric Motor Unit(EMU) and Stainless Steel(STS) body Electric Motor Unit(EMU). LCA process consists of four steps which are goal, scope definition, life cycle impact analysis(LCIA) and life cycle interpretation. ISO 14044 provides the LCA standard method which can be conducted by using comparative LCA. From the research it is foung that the Aluminium Body Electric Motor Unit (EMU) is 3.6ton heaver than Stainless Steel(STS) body Electric Motor Unit(EMU). The system boundary of both Electric Motor Unit (EMU) are same life span and travel same distance. These both Electric Motor Unit (EMU) has same kind of environmental impact which is maximum Ozone Depletion(OD). During using period of these two models, the Aluminium Body Electric Motor Unit(EMU) has more global warming(GW) effect but Stainless Steel(STS) body Electric Motor Unit(EMU) has more Ozone Depletion(OD) effect. The above result is obtained by using LCA software PASS verson 3.1.3.

• Advances in Traditional Medicine
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• 제5권4호
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• pp.322-330
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• 2005

The plant Bryonia laciniosa (Family: Cucurbitaceae) has been indicated for the treatment of various diseases one among which is cancer. The purpose of this study was investigating experimentally the possible anti-tumor effect and antioxidant role of Bryonia laciniosa leaves in animal model. The methanol extract of Bryonia laciniosa (MEBL) administered at the doses of 62.5, 125 and 250 mg/kg in mice for 14 days after 24 h of tumor inoculation. The effect of MEBL on the growth of transplantable murine tumor, life span of EAC bearing mice, hematological profile and liver biochemical parameters (lipid peroxidation, antioxidant enzymes) were estimated. Treatment with MEBL decreased the tumor volume and viable cell count thereby increasing the life span of EAC bearing mice and brought back the hematological parameter more or less normal level. The effect of MEBL also decreases the levels of lipid peroxidation and increased the levels of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). The present work indicates that the methanol extract of Bryonia laciniosa exhibited significant antitumor and antioxidant activity in vivo.

• 대한한의학회지
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• 제26권1호
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• pp.1-10
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• 2005

Objective: We examined the antimetastatic effect of Curcuma zedoaria Roscoe (CZ) on pulmonary metastasis of B 16 cells. Methods: For 6 weeks, Zedoariae Rhizoma made from dried CZ were dissolved in distilled water and administered to mice 2 weeks before they were injected with B]6 melanoma cells. Mice were given CZ at doses of 250 and 500 mg/kg, and were compared for lung weight, survival days, and NO production. Results: Intake of CZ throughout the experiment extended the average survival time. Intake after B16 cell injection slightly prolonged survival time, but intake before B]6 cell injection did not influence life span. We examined the effect of CZ on macrophage function by measuring NO production. After the macrophages were given CZ for 6 weeks, the amount of NO generated by the macrophages stimulated with LPS in culture medium increased. NO generated by the macrophages also served as a cytotoxic factor against B16 melanoma cells. B16 melanoma-conditioned medium reduced NO production by macrophages. However, CZ treatment reversed the reduction in NO production by the conditioned medium significantly. Conclusion : These findings may suggest that macrophage function-modulating activity by CZ appears to underlie its antimetastatic activity, which leads to a decrease in the number of lung metastatic surface nodules and the extension of life span.

• Structural Engineering and Mechanics
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• 제74권2호
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• pp.157-173
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• 2020

In the finite element modelling of long-span cable-stayed bridges, there are a lot of uncertainties brought about by the complex structural configuration, material behaviour, boundary conditions, structural connections, etc. In order to reduce the discrepancies between the theoretical finite element model and the actual static and dynamic behaviour, updating is indispensable after establishment of the finite element model to provide a reliable baseline version for further analysis. Traditional sensitivity-based updating methods cannot support updating based on static and dynamic measurement data at the same time. The finite element model is required in every optimization iteration which limits the efficiency greatly. A convenient but accurate Kriging surrogate model for updating of the finite element model of cable-stayed bridge is proposed. First, a simple cable-stayed bridge is used to verify the method and the updating results of Kriging model are compared with those using the response surface model. Results show that Kriging model has higher accuracy than the response surface model. Then the method is utilized to update the model of a long-span cable-stayed bridge in Hong Kong. The natural frequencies are extracted using various methods from the ambient data collected by the Wind and Structural Health Monitoring System installed on the bridge. The maximum deflection records at two specific locations in the load test form the updating objective function. Finally, the fatigue lives of the structure at two cross sections are calculated with the finite element models before and after updating considering the mean stress effect. Results are compared with those calculated from the strain gauge data for verification.

• Journal of Nutrition and Health
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• 제36권4호
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• pp.368-375
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• 2003

Cancer cachexia, characterized by weight loss and progressive tissue wasting, has been postulated to be mediated by cytokines. This study was conducted to evaluate the effect of Korean Traditional Medicine (KTM ; mokhyang, jisil, osooyu) mixture on food intake, blood cytokines level and blood nutrients status of the cachexia induced-mice. Thirty male Balb/c mice aged 6-8 weets were blocked into 3 groups that were Normal (no colon26 cells) Control (colon 26 cells) and KTM (colon26 cells + KTM extract mixture) group. In Control and KTM groups, murine adenocarcinoma colon 26 cells were injected subcutaneously to induce cachexia. KTM mice were given 200 ul KTM extract mixture (7%) per day. Half of each groups were sacrificed at the 14 th day to see serum cytokines & nutrients and the others were fed until almost of control group died to see life span. food intake and body weight were decreased significantly in cachexia induced groups. Tumor weight of KTM group was significantly lower than control group. Serum cytokines (IL-1$\beta$ and TNF-$\alpha$) level of cachexia induced groups were increased than those of normal group, and those of KTM group were significantly lower than the level of control group. Total serum protein and serum albumin were higher in KTM group than other groups. TG and fatty acid were lower in cachexia induced groups than normal group. HDL-cholesterol in serum was increased in KTM group. Effect of oral administration of KTM extract mixture on survival time of colon26 bearing mice showed extension of the life span. Overall, this study showed that KTM (mokhyang, jisil, osooyu) extract mixture inhibited the growth of cancer cell, changed the secretion of cytokines induced by colon26 adenocarcinoma in mice, and changed nutrition metabolism.

• 약학회지
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• 제38권2호
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• pp.166-173
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• 1994

Sex hormones not only regulate external sexual characteristics but several internal biochemical processes. It is well accepted that life-span of female is longer than that of male. Life-span is closely related with aging process in which free radicals are known to be involved. We investigated the effect of testosterone on free radical generating systems and lipid peroxidation based on the sexual difference. Lipid peroxide levels of male and female mouse were increased proportionately with age, especially in male mouse. Increase in enzyme activity of aldehyde oxidase with age was observed in male mouse, while no siginificant change in enzyme activity was found in female mouse. Enzyme activity of xanthine oxidase also showed similar results. It, however, was not significant statistically. Lipid peroxide level and xanthine oxidase type conversion ratio of male and female mouse liver homogenate incubated at $37^{\circ}C$, increased remarkably in proportion to incubation time, especially in male mouse. Lipid peroxide level and aldehyde oxidase activity were measured in normal male mouse, castrated mouse and testosterone treated-castrated mouse. Castrated mouse group showed decrease in lipid peroxide level and aldehyde oxidase activity compared with normal group. Treatment of castrated mouse with testosterone, however turned the level of lipid peroxide and aldehyde oxidase activity back to normal. From the above results, it might be concluded that testosteron could increase the activities of free radical generating enzymes which would result in the formation of lipid peroxide, consequently leading to aging.

• 한국미생물·생명공학회지
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• 제24권1호
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• pp.37-43
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• 1996

Augmentation of antitumor activity of antitumor drugs in combination with Lactobacillus casei HY2782 (LC2782) was studied against Sarcoma-180 (S-180) and Lewis lung carcinoma (3LL). Antitumor drugs used in this study were 5-fluorouracil (5-fu) and cyclophosphamide (CP). The prolongation effect of LC2872 on the life span of mouse intraperitoneally implanted with S-180 was stronger than that of OK-432 and BCG, while the inhibitory effect of OK-432 and BCG on the growth of 3LL solid tumor was a little stronger than that of LC2782. Average survival rates of mice administrated LC2782, OK-432 and BCG were 192%, 141%, and 112%, respectively, when that of the control was 100%, Intralesional administration of 5-Fu, CP, 5-Fu+LC2782 and CP+LC2782 resulted in 93%, 69%, 99% and 73% inhibition rates against 3LL solid tumor proliferation. The combination therapy of 5-Fu or CP with LC2782 significantly prolonged the life span of S-180-inoculated ICR mice. Average survival rates of mice administrated 5-Fu and CP alone were 115% and 99%. Furthermore, survival rates of mice administrated 5-Fu and CP in combination with LC2782 were 226% and 244%, respectively.