• Title/Summary/Keyword: damage factor

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Interpretation of Eum-Yang' Deficiency, Excess and Exuberance which was described in "Somun.Jogyeongron(素問.調經論)" ("소문(素問).조경론(調經論)"의 음양허성(陰陽虛盛)에 대(對)한 연구(硏究))

  • Kim, Sun-Hyung;Bang, Jung-Kyun
    • Journal of Korean Medical classics
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    • v.22 no.1
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    • pp.103-109
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    • 2009
  • It was described in "Somun Jogyeongron" that Eum(Yin)-Yang' deficiency, excess and exuberance. According to "Somun Jogyeongron", It was known that the syndrome of Yang deficiency and exuberance is belong to external contraction, Eum deficiency and exuberance is belong to internal damage. The syndrome of Yang deficiency is belong to Gyejitang[contraction of wind] which constitutional weakness as the main etiological factor of deficiency conditions. The syndrome of Yang exuberance is belong to Mahwangtang[cold damage] which constitutional strong as the main etiological factor of exuberance conditions. Eum deficiency is so dysfunction of the spleen and stomach that Eum fluid and essence is not engender, distributed. So the dysfunction of spleen and stomach makes dampness-heat obstruction and then makes Internal heat at last. The syndrome of Eum deficiency is applicable to bojungikgitang. As contrasted with Eum deficiency, Eum exuberance is occurred cold-dampness obstruction, which we call 'Eum exuberance'. The syndrome of Yang exuberance is applicable to Ijungtang. In the light of "Somun Jogyongron", We explain that the syndrome of Yin deficiency and Yin exuberance, which was caused by dampness-heat, cold-dampness obstruction and internal damage based on disorder of the spleen and stomach.

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A Study on the Evaluation of Linear Cumulative Damage Factor of Membrane Type LNG Tank by use of Probability Density Function (확률밀도함수를 이용한 멤브레인방식 LNG탱크의 선형누적손상도 평가에 관한 연구)

  • 김종호
    • Journal of Advanced Marine Engineering and Technology
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    • v.28 no.6
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    • pp.993-999
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    • 2004
  • The estimation of fatigue life at the design stage of membrane type LNG tank is very important in order to arrive at feasible and cost effective solutions considering the total lifetime of the tank. In this study, the practical procedure of fatigue life prediction by use of cumulative damage factors based on Miner-Palmgren hypothesis and probability density function has been shown with the corner region of Gaz Transport Membrane type LNG tank being used as an example. In particular the parameters of Weibull distribution that determine the stress spectrum are discussed. The main results obtained from this study are as follows: 1. The recommended value for the shape parameter of Weibull distribution for the LNG tank is 1.1 in case of using the direct calculation method proposed in this study. 2. The calculated fatigue life is influenced by the shape parameter of Weibull distribution and stress block. The safe fatigue design can be achieved by using higher value of shape parameter and the stress blocks divided into more stress blocks.

Protection against Whole Body γ-Irradiation Induced Oxidative Stress and Clastogenic Damage in Mice by Ginger Essential Oil

  • Jeena, Kottarapat;Liju, Vijayasteltar B;Ramanath, Viswanathan;Kuttan, Ramadasan
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.1325-1332
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    • 2016
  • Radioprotective effects of ginger essential oil (GEO) on mortality, body weight alteration, hematological parameters, antioxidant status and chromosomal damage were studied in irradiated mice. Regression analysis of survival data in mice exposed to radiation yielded LD50/30 as 7.12 and 10.14 Gy for control (irradiation alone) and experimental (GEO-treated irradiated) mice, respectively, with a dose reduction factor (DRF) of 1.42. In mice exposed to whole-body gamma-irradiation (6 Gy), GEO pre-treatment at 100 and 500 mg/kg b.wt (orally) significantly ameliorated decreased hematological and immunological parameters. Radiation induced reduction in intestinal tissue antioxidant enzyme levels such as superoxide dismutase, catalase, glutathione peroxidase and glutathione was also reversed following administration of GEO. Tissue architecture of small intestine which was damaged following irradiation was improved upon administration of GEO. Anticlastogenic effects of GEO were studied by micronuclei assay, chromosomal aberration and alkaline gel electrophoresis assay. GEO significantly decreased the formation of micronuclei, increased the P/N ratio, inhibited the formation of chromosomal aberrations and protected agaisnt cellular DNA damage in bone marrow cells as revealed by comet assay. These results are supportive of use of GEO as a potential radioprotective compound.

The Response of the Structure with the Damage Curve (손상곡선에 의한 구조물의 거동파악)

  • Lee, Sang-Ho;Song, Hyun-Seop
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.9 no.1
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    • pp.189-196
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    • 2005
  • The effects of the impulse and the magnitude of the impulsive loads to the responses of the structure are analyzed with the safety criteria established with the peak load and impulse ratio. It is shown for the loadings with short duration that the impulse is dominant factor for the damage of the structures due to the inertial effect. On the other hand the magnitude of the load is dominant factor for the load with long duration due to the duration time long enough for the loads to overcome the inertia force. It is also shown that the peak particle velocity and the peak particle acceleration of the foundation have the same influences as the impulse and the magnitude of the loads do to the structures.

A Study on the Prediction of Fatigue Life by use of Probability Density Function (확률밀도함수를 이용한 피로균열 발생수명 예측에 관한 연구)

  • 김종호
    • Journal of Advanced Marine Engineering and Technology
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    • v.23 no.4
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    • pp.453-461
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    • 1999
  • The estimation of fatigue life at the design stage is very important in order to arrive at feasible and cost effective solutions considering the total lifetime of the structure and machinery compo-nents. In this study the practical procedure of prediction of fatigue life by use of cumulative damage factors based on Miner-Palmgren hypothesis and probability density function is shown with a $135,000m^3$ LNG tank being used as an example. In particular the parameters of Weibull distribution taht determine the stress spectrum are dis-cussed. At the end some of uncertainties associated with fatigue life prediction are discussed. The main results obtained from this study are as follows: 1. The practical procedure of prediction of fatigue life by use of cumulative damage factors expressed in combination of probability density function and S-N data is proposed. 2. The calculated fatigue life is influenced by the shape parameter and stress block. The conser-vative fatigue design can be achieved when using higher value of shape parameter and the stress blocks divded into more stress blocks.

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Satisfaction Factors and Determinants of Visitors in Bukhansan National Park, Korea (북한산국립공원 탐방객 만족요인 및 예측모형)

  • Baek, Jae-Bong;Kim, Dong-Pil
    • Korean Journal of Environment and Ecology
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    • v.22 no.2
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    • pp.113-118
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    • 2008
  • This study was carried out with the aim to provide basic data for efficient park management by analyzing satisfaction factors and estimated regression model through questionnaire survey method for the visitors to Bukhansan National Park in Korea. As a result of analysis, it was found that visitors are satisfied with such variables as 'illegal camping', 'cooking act' and 'padded bills' but extremely unsatisfied with 'waste problem', 'congestion', 'damage of visiting trails' and 'lack of cultural facilities'. In the result of satisfaction factors, it was revealed that 'facility management factor' was found to have the greatest effect on satisfaction degree. In the estimated model by Multiple Regression Analysis, 'damage of natural resources' and 'damage of cultural and historic resources', and 'lack of traffic facilities' were found to affect visitors' satisfaction.

Photoprotection effect of Pu'er tea and Curcuma longa L. extracts against UV and blue lights

  • Doyeong Son;Ji-Su Jun;KwangWon Hong
    • Journal of Applied Biological Chemistry
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    • v.66
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    • pp.106-113
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    • 2023
  • Plant extracts have been studied due to their potential as photoprotective agents against UV and blue light exposure. Previous studies have revealed that several plant extracts have photoprotection capacities and synergistic effects with synthetic products. However, such results for pu'er tea and Curcuma longa L. have not been reported yet for a cosmetic formulation. Thus, the objective of this study was to evaluate photoprotection capacities of pu'er tea and C. longa L. extracts for a sunscreen compound. The pu'er tea extract improved sun protection factor value of 2-ethyl-hexyl methoxycinnamate (a synthetic sunscreen compound) by 46% and showed a high antioxidant capability that could help skin recover from photo-induced damage. C. longa L. extract also showed a potential to protect skin from blue light-induced damage because it not only had a maximum absorption peak at the blue light range, but also protected human fibroblasts from blue light-induced damage. The addition of both extracts shifted the critical wavelength of 2-ethyl-hexyl methoxycinnamate from 350 nm to 386 nm, giving it a broad-spectrum feature. Thus, pu'er tea and C. longa L. extracts may enhance the photoprotection ability of synthetic sunscreen products.

Assessment of casting parts fatigue life for 3MW offshore wind turbine (3MW 해상풍력발전기 주물품의 내구수명 평가)

  • Roh, Gitae;Kang, Wonhyoung;Lee, Seongchan
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.11a
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    • pp.189.2-189.2
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    • 2010
  • The purpose of this study is fatigue damage assessment for large sized casting parts (hub and mainframe) of the 3MW offshore wind turbine by computer simulation. Hub and mainframe durability assessment is necessary because wind turbine have to guarantee for 20 years. Fatigue life evaluation must be considered all of fatigue load conditions as the components are wind load transmission path. Palmgren-Miner linear damage accumulation hypothesis is applied for fatigue life estimation with stress-life approach. S-N curve for the spheroid graphite cast iron EN-GJS-400-18-LT is derived according to durability guidelines. Reduction factors were applied for survival probability, surface roughness, material quality and partial safety factor according to Germanischer Lloyd rules. To calculate fatigue damage, stress tensors, extracted from the unity load calculation from ANSYS is multiplied with time track of fatigue loads extracted from GH bladed. Damage accumulation is performed with all of fatigue load conditions at each finite element nodes. In this study maximum nodal damage value is under 1.0. casted parts are safe. This research was financially supported by the Ministry of Knowledge Economy(MKE), Korea Institute for Advancement of Technology(KIAT) and Honam Leading Industry Office through the Leading Industry Development for Economic Region.

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Relative Road Damage Analysis with Driving Modes of a Military Vehicle (군용차량의 주행모드에 따른 상대 노면 가혹도 분석)

  • Suh, Kwonhee;Song, Bugeun;Yoon, Hiseak
    • Transactions of the Korean Society of Automotive Engineers
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    • v.24 no.2
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    • pp.225-231
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    • 2016
  • A military vehicle is driven at different usage modes with the army application and servicing conditions. For practical durability validation, DT(Development Test) on a new military vehicle should be run up to the durability target kilometers on test courses in the specified proving ground. Driving velocities with test courses at the endurance mode of DT are established definitely. However, OT(Operational Test) and initial endurance test of production car can't be performed only in the DT courses due to the development period limit. Therefore, this paper focuses on the method to analyze the relative road damages between the endurance test in DT and other endurance test. Road load acquisition tests on KLTV(Korean Light Tactical Vehicle) were implemented at 15 driving modes in off-road and cross-country courses of two tests. Wheel accelerations were processed through band-pass filter, and then the main frequency and maximum power of the signals were computed by PSD analysis. Finally, using the proving ground optimization based on RDS(Relative Damage Spectrum) characterization, the damage factors between off-roads of test courses were determined.

Numerical simulation of fracture and damage behaviour of concrete at different ages

  • Jin, Nanguo;Tian, Ye;Jin, Xianyu
    • Computers and Concrete
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    • v.4 no.3
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    • pp.221-241
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    • 2007
  • Based on the experiment results, the damage and fracture behavior of concrete at the ages of 1d, 2d, 7d and 28d, in three-point bending and uniaxial tensile tests, were simulated with a finite element program, ABAQUS. The critical stress intensity factor $K_{IC}^s$ and the critical crack tip opening displacement ($CTOD_C$) of concrete were calculated with effective-elastic crack approach for the three-point bending test of grade C30 concrete. Based on the crack band model, a bilinear strain-softening curve was derived to simulate the LOAD-CMOD curves and LOAD-Displacement curves. In numerical analysis of the uniaxial tension test of concrete of grade C40, the damage and fracture mechanics were combined. The smeared cracking model coupling with damaged variable was adopted to evaluate the onset and development of microcracking of uniaxial tensile specimen. The uniaxial tension test was simulated by invoking the damage plastic model which took both damage and plasticity as inner variables with user subroutines. All the numerical simulated results show good agreement with the experimental results.