• Steel and Composite Structures
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• v.21 no.1
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• pp.57-72
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• 2016

The Poisson ratio reduction of symmetric hygrothermal aged $[{\theta}_m/90_n]_s$ composite laminates containing a transverse cracking in mid-layer is predicted by using a modified shear-lag model. Good agreement is obtained by comparing the prediction models and experimental data published by Joffe et al. (2001). The material properties of the composite are affected by the variation of temperature and transient moisture concentration distribution in desorption case, and are based on a micro-mechanical model of laminates. The transient and non-uniform moisture concentration distribution give rise to the transient Poisson ratio reduction. The obtained results represent well the dependence of the Poisson ratio degradation on the cracks density, fibre orientation angle of the outer layers and transient environmental conditions. Through the presented study, we hope to contribute to the understanding of the hygrothermal behaviour of cracked composite laminate.

• Structural Engineering and Mechanics
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• v.67 no.2
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• pp.165-173
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• 2018

A simple predicted model using a modified Shear-lag method was used to represent the moisture absorption effect on the stiffness degradation for $[0/90]_{2s}$ composite laminates with transverse cracks and under flexural loading. Good agreement is obtained by comparing the prediction model and experimental data published by Smith and Ogin (2000). The material properties of the composite are affected by the variation of temperature and moisture absorption. The transient and non-uniform moisture concentration distribution give rise to the transient elastic moduli of cracked composite laminates. The hygrothermal effect is taken into account to assess the changes in the normalised axial and flexural modulus due to transverse crack. The obtained results represent well the dependence of the stiffness properties degradation on the cracks density, moisture absorption and operational temperature. The composite laminate with transverse crack loaded in axial tension is more affected by the hygrothermal condition than the one under flexural loading. Through this theoretical study, we hope to contribute to the understanding of the moisture absorption on the composite materials with matrix cracking.

• Advances in aircraft and spacecraft science
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• v.6 no.4
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• pp.315-331
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• 2019

The stiffness degradation of the cross-ply composite laminates containing a transverse cracking and delamination in $90^{\circ}$ layer is predicted by using a modified shear-lag model by introducing the stress perturbation function. The prediction shows better agreement with the experimental results published by Ogihara and Takeda 1995, especially for laminates with thicker $90^{\circ}$ plies in which extensive delamination occurs. A homogenised analytic model for average transient moisture uptake in composite laminates containing periodically distributed matrix cracks and delamination is presented. It is shown that the model well describes the moisture absorption in a cross-ply composite laminate containing periodically distributed transverse matrix cracks in the $90^{\circ}$ plies. The obtained results represent well the dependence of the stiffness degradation on the crack density, thickness ratio and moisture absorption. The present study has proved to be important to the understanding of the degradation of the material propertiesin the failure process when the laminates in which the delamination grows extensively.

• Journal of Life Science
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• v.11 no.6
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• pp.603-611
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• 2001

Phytolalexins are produced in plants affected by various environmental factors such as fungal infection treatment with many chemicals and irradiation by ultraviolet light. When pepper and tobacco bel suspension cultures were grown on a basal MS medium supplemented with 2,4-D(1mg/$\ell$, benzyl adenine(0.001 mg/$\ell$) and 100$\mu$ M jasmonic acid, the production of capsidiol was observed. The total of compound found in pepper plant were around seventy and thirty of them were located intissue-specific manner. 1-propanethiol, $\alpha$-D-xylofuranoside, phenol, hexadecanonic acid ethyl tridecanoate, phytol, linoleic acid and capsidiol are those which have change the production level by treatments, such as the inoculation of Phytophthora capsici Leonian, the metalaxyl treatment and the UV-B irradiation, respectively. The content of capsidiol on inoculation of P. capsici with metalxyl suspension in soil were higher than those of P.capsici without metalaxyl. When the soil dernch of metalaxyl treatment (1$\mu\textrm{g}$/${mu}ell$)was delayed after inoculation, the content of capsidiol were higher than that of before. Irrradiated UB-B the production on capsidiol was identified only at leaf, and contents were the highest for 24 hrs incubation after 20 minutes irradiation.

• Steel and Composite Structures
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• v.42 no.4
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• pp.501-511
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• 2022

Earthquake Resistant Design Philosophy seeks (a) no damage, (b) no significant structural damage, and (c) significant structural damage but no collapse of normal buildings, under minor, moderate and severe levels of earthquake shaking, respectively. A procedure is proposed for seismic design of low-rise reinforced concrete special moment frame buildings, which is consistent with this philosophy; buildings are designed to be ductile through appropriate sizing and reinforcement detailing, such that they resist severe level of earthquake shaking without collapse. Nonlinear analyses of study buildings are used to determine quantitatively (a) ranges of design parameters required to assure the required deformability in normal buildings to resist the severe level of earthquake shaking, (b) four specific limit states that represent the start of different structural damage states, and (c) levels of minor and moderate earthquake shakings stated in the philosophy along with an extreme level of earthquake shaking associated with the structural damage state of no collapse. The four limits of structural damage states and the three levels of earthquake shaking identified are shown to be consistent with the performance-based design guidelines available in literature. Finally, nonlinear analyses results are used to confirm the efficacy of the proposed procedure.

• Journal of Korean Society of Transportation
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• v.20 no.7
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• pp.15-22
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• 2002

Transportation project appraisal should be precise in order to increase the social welfare and efficiency, and it has been evaluated by only a single criterion analysis such as benefit/cost analysis. However, this method cannot assess some qualitative items, and cannot get a proper solution for the clash of interests among various groups. Therefore, the multi-criteria analysis, which can control these problems, is needed, and then Saaty has developed one of these methods, AHP(Analytic Hierarchy Process) method. In AHP, the project is evaluated through weighted score of the criteria and the alternatives, which is surveyed by a questionnaire of specialists. It is based on some strict suppositions such as reciprocal comparison, homogeneity, expectation, independence relationship between multi-criteria, but supposing that each criterion has independence relation with others is too difficult in two reasons. First, in real situation, there cannot be perfect independence relationship between standards. Second, individuals, even though they are specialists of that area, do not feel the degree of independence relation as same as others. This paper develops a modified AHP method for solving this dependence relationship between multi-criteria. First of all. in this method, the degree of dependence relationship between multi-criteria that the specialist feels is surveyed and included to the weighted score of multi-criteria This study supposes three methods to implement this idea. The first model products the degree of dependence relationship in the first step for calculating the weighted score, and the others adjust the result of weighted score from the basic AHP method to the dependence relationship. One of the second methods distributes the cross weighted score to each standard by constant ratio, and the other splits them using Fuzzy measure such as Bel and Pl. Finally, in order to validate these methods, this paper applies them to evaluate the alternatives which can control public resentments against Korean rail path in a city area.

• Journal of Acupuncture Research
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• v.27 no.2
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• pp.1-10
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• 2010

Objectives : The 7-zone-diagnostic system is a diagnostic device to predetermine bodily locations by measuring the energy of body. This study was to investigate the relation between the different patterns of Zone 2 of Factor AA in CP-6000A (VEGA, Germany), 7-zone-diagnostic system and the factors of Bell's Palsy. Methods : This study was carried out with the data from factors of Bell's Palsy(age, sex, period after onset, postauricular pain, season which the disease happen, contributing factor). We made three groups according to the different patterns of Zone 2 of Factor AA in CP-6000A. The Factor AA pattern of Group A is that the red bar graph of zone 2 were lower than the normal range. The Factor AA pattern of Group B was that the red bar graph of zone 2 was the normal range. The Factor AA pattern of Group C was that the red bar graph of zone 2 was higher than the normal range. After collecting the data about factors of Bel's Palsy to correspond with conditions of each group were selected, the data was analyzed statistically. Results : The values of number of patient and period after onset of group A was higher than group B and C. The values of ratio of postauricular pain of group B and C was higher than group A. The season of disease happened of group A is spring and winter, group B is winter and group C is summer and autumn. The contributing factor of disease happened of group A is none, and group B and C is stress and clod. Conclusions : In Bell's Palsy, it is thought that the red bar graph of zone 2 is lower, the group have lower energy(虛) and the energy has a character of cold(寒), and zone 2 is higher, the group has the higher energy(實) and the energy has a character of fire(熱).

• Korean Journal of Microbiology
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• v.37 no.3
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• pp.177-181
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• 2001

It is previously reported that Bacillus licheniformis B1 strain isolated from nature was successfully used for Chungkookjang fermentation. Antioxidant activity of its powder was determined in this study. Sephadex G-75 gel filtration chromatography was performed, far soluble fractions of the powder extracted by distilled water. The soluble fractions were separated into large and small fractions. The substance 1,1-diphenyl-2-picrylhydrazyl (DPPH) was used as an electron acceptor. Antioxidant activity was found in the small fractions. Five% solution of the Chungkookjang powder was the most effective in the extraction of antioxidant substances from the powder. It was proven in this study that strong antioxidant activity still remained in the Chungkookjang powder.

• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.31-36
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• 1991

A 7.5 kilobases hybrid plasmid, designated as pCE1301, was constructed by combining Eschurichia cwli plasmid pBELl which carries the kanamycin resistance gene of Tn5 with a cryptic plasmid, pSRl of Corynebacterium glutamicum. pCE1301 was transformed C. glutaicum by PEG-mediated protoplast method and its transformation efficiency was about $3.0\times 10^3$ transformants per $\mu g$ of the hybrid plasmid DNA. The physical map reveals that pCE1301 has single restriction sites for SalI and EcoRl, respectively. 'The kanamycin resistance of pCE1301 was stably maintained in C. glutamicum up to 25 generations and any segregation was not detected. pCI31301 was also introduced into Brevibacterium flavum and E coil, and replicated in those strains. pCE1301 was proved to be useiul in cloning the homoscrine dehydrogenase gene from C. glutamicum.