• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.8
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• pp.2033-2042
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• 1993

In conventional SCC susceptibility test, there are constant strain test, constant load test, slow strain rate test(SSRT) and K$_{ISCC}$ test. Among them, the SSRT method is much more aggressive in producing SCC than the other tests, so that the test time of it is considerably reduced. But this SSRT method has mostly been worked using the uniaxial tensile specimen untill now. Therefore, the SSRT method using the tensile specimen(Ten-SSRT) has much difficulty in SCC susceptibility evaluation of a localized region like weldment and the advantage material of high order. Recentely, the small punch(SP) test method using miniaturized small specimen is the very effective test method for fracture strength evaluation of a localized region like weldment and fusion reactor wall irradiated in the nuclear power plant. This paper investigated the possibility of SCC susceptibility evaluation by the SP-SSRT method using the miniaturized small specimen. Therefore, we obtained the result that the SP-SSRT had the possibility for the evaluations of SCC susceptibility for shorter time to corrosive environment compare to Ten-SSRT which was conventional method.

• Journal of Welding and Joining
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• v.13 no.4
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• pp.46-54
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• 1995

The cold cracking susceptibility of a variety of weld metals deposited by GMAW with several kinds of commercial solid wires for high strength-toughness steel was investigated. G-BOP test and LB-TRC test were carried out to study the effects of preheat, chemical composition and hydrogen level on the weld metal cold cracking. The results obtained are as follows. 1) 10% CPT obtained by G-BOP test was the most valuable criteria for evaluating the cold cracking susceptibility of weld metals compared with percentage of cracking at room temperature and crack free temperature, and it had good correlation with the results of LB-TRC test. 2) Cold cracking susceptibility of weld metals was high in the row of MG100A, MG100C, MG100D and MG100B. Welds deposited with MG130 and MG80 showed similar icidents of cracking with MG100C and MG100B respectively, even though their strength levels were different. 3) Diffusible hydrogen level in weld metals which has good relation with hydrogen content in wire itself was the most critical factor for controlling the cold cracking susceptibility of weld metal.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.7
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• pp.931-941
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• 1998

The purpose of this study were 1) to identify the effects of the self-efficacy, sensation seeking and delinquency on female adolescents' clothing behavior, and 2) to identify the differences in self-efficacy, sensation seeking, deliquency and clothing behavior in relation to the demographic variables. The data were collected from 435 high school girls living in Seoul, via a self-administered questionnaires, and were analyzed by factor analysis, Peason's correlation, multiple regression, one-way ANOVA and SNK test. The result of this study were as follows: As the result of analyzing the effects of self-efficacy, efficacy, sensating seeking and delinquency on each of clothing behavior variables, fashion leadership was explained by the factors such as social self-efficacy, delinquency and boredom susceptibility, and psychological clothing dependence by boredom susceptibility, social self-efficacy, and thrill and adventure, clothing exhibition by boredom susceptibility, delinquency, and general self-efficacy, social approval by boredom susceptibility, and general self-efficacy, preference for up-to-data style by delinquency, boredom susceptibility by delinquency, boredom susceptibility. There were significant differences between the two types of school in general self-efficacy, thrill and adventure, experience seeking, delinquency, preference for up-to-data style, and appearance related delinquency. Location of school had the effects on experience seeking, delinquency, fashion leadership, and appearance related delinquency, and socioeconomic status on fashion leadership.

• International Journal of Highway Engineering
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• v.17 no.1
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• pp.77-82
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• 2015

PURPOSES : The purpose of this paper is to evaluate the moisture susceptibility of asphalt mixtures containing developed liquid anti-stripping agents using the boiling water test as a screening test. METHODS : The boiling water test was used to evaluate the moisture susceptibility of asphalt mixtures containing different anti-stripping agents. The tensile strength ratio was calculated to compare the moisture susceptibility of the asphalt mixtures after indirect strength tests were performed. Additionally, image analysis techniques were used to calculate and analyze the quantity of stripped area in the asphalt mixtures. RESULTS : In general, the asphalt mixtures containing anti-stripping agents showed a higher resistance of anti-stripping based on the boiling water test and tensile strength ratio. CONCLUSIONS : The boiling water test can be used to differentiate the resistance of moisture susceptibility of asphalt mixtures, except for asphalt mixtures containing hydrated lime. The boiling water test can be used as a screening test for asphalt mixtures before conducting time consuming and expensive indirect tensile strength tests.

• Journal of Veterinary Clinics
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• v.34 no.3
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• pp.161-164
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• 2017

Bovine respiratory disease (BRD) is one of the most important diseases in calves. It causes a huge economic loss in farms. BRD in calves is concentrated during winter because of the cold weather and lack of ventilation. However, BRD during summer in calves has continuously been a problem in farms. But there is no study about pathogens of summer pneumonia in calves and antimicrobial susceptibility in Korea. Therefore, aims of this study were to identify the pathogens and their antimicrobial susceptibility in calves with summer pneumonia. One hundred and one calves (2 weeks to 5 months after birth) with clinical sign of BRD from 5 farms were selected. After sampling by deep nasal swab, bacterial isolation and identification was conducted. Also, antimicrobial susceptibility test was performed. Pasteurella spp (49.4%), Staphylococcus spp (21.5%), Actinomyces spp (12.9%), E coli (10.7%), and Mannheimia haemolytica (5.3%) were isolated. The patterns of isolated pathogens from each farm were various. Also, the susceptibility of bacteria to antibiotics was showed a variety of patterns in each farm.

• Corrosion Science and Technology
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• v.2 no.3
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• pp.109-116
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• 2003

It is well known that SSCC (sulfide stress corrosion cracking) is caused by drastic ingression of hydrogen during the service and accumulation of hydrogen near the potential crack initiation site in the material. It is important to characterize the hydrogen trapping behavior to evaluate the service performance of the high strength pipeline steels. In this study. the relationship between the hydrogen trapping behavior and SSCC susceptibility is evaluated in terms of alloy composition, microstructure and carbide behavior. The hydrogen trapping behavior was measured by electrochemical hydrogen permeation test cell (Devanathan cell). The SSCC susceptibility is evaluated by constant extension rate test and constant strain lest method. The hydrogen trapping behavior is affected greatly by microstructure and nature of carbide particles. The fine TiC, and NbC in the matrix of ferritic structure acts as strong irreversible trap sites whereas the bainitic structure acts as reversible trap site. The SSCC susceptibility is closely related to not only the hydrogen trapping behavior but also the loading condition. As the activity of reversible trap site increases, SSCC susceptibility decreases under static loading condition below yield strength, whereas SSCC susceptibility increases under dynamic loading condition or above yield strength. As the activity of irreversible trap site increases. SSCC susceptibility increases regardless of loading condition. It is cased by the mixed effect of dislocation on hydrogen diffusion and trapping behavior.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.9
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• pp.1419-1429
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• 2009

This study tests the validity of the Susceptibility of Global Consumer Culture (SGCC) Scale that is composed of three dimensions, conformity to consumption trend, quality perception, and social prestige, on Korean consumers. The study also identifies the relationships with consumer susceptibility to interpersonal influence and attitude toward purchasing global fashion brands. Utilizing the convenience sampling method, college students aged over 20 living in the Seoul metropolitan area were selected. Three hundred questionnaires were used in the statistical analysis, exploratory and confirmatory factor analysis, paired t test, and path analysis using structural equation modeling. Confirmatory factor analysis revealed that the SGCC scale measured by three dimensions fit well for young Korean consumers. Path analysis showed that identical conformity positively influences all three dimensions of the SGCC scale and that informational conformity positively influences purchasing intention toward global fashion brands. Among the three dimensions of SGCC, quality perception and social prestige positively influence purchasing intention toward global fashion brands.

• Research in Plant Disease
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• v.25 no.3
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• pp.103-107
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• 2019

Roles of nutrients in controlling plant diseases have been documented for a long time. Among the nutrients having impact on susceptibility/resistance to crop diseases, nitrogen is one of the most important nutrients for plant growth and development. In rice plants, excess nitrogen via fertilization in agricultural systems is known to increase susceptibility to the rice blast disease. Mechanisms underlying such phenomenon, despite its implication in yield and sustainable agriculture, have not been fully elucidated yet. A few research efforts attempted to link nitrogen-induced susceptibility to concomitant changes in rice plant and rice blast fungus in response to excess nitrogen. However, recent studies focusing on phytobiome are offering new insights into effects of nitrogen on interaction between plants and pathogens. In this review, I will first briefly describe importance of nitrogen as a key nutrient for plants and what changes excess nitrogen can bring about in rice and the fungal pathogen. Next, I will highlight some of the recent phytobiome studies relevant to nitrogen utilization and immunity of plants. Finally, I propose the hypothesis that changes in phytobiome upon excessive nitrogen fertilization contribute to nitrogen-induced susceptibility, and discuss empirical evidences that are needed to support the hypothesis.

• Journal of Microbiology and Biotechnology
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• v.33 no.2
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• pp.180-187
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• 2023

The skin is a dynamic ecosystem on which diverse microbes reside. The interkingdom interaction between microbial species in the skin microbiota is thought to influence the health and disease of the skin although the roles of the intra- and interkingdom interactions remain to be elucidated. In this context, the interactions between Malassezia and Staphylococcus, the most dominant microorganisms in the skin microbiota, have gained attention. This study investigated how the interaction between Malassezia and Staphylococcus affected the antifungal susceptibility of the fungus to the azole antifungal drug ketoconazole. The susceptibility was significantly decreased when Malassezia was co-cultured with Staphylococcus. We found that acidification of the environment by organic acids produced by Staphylococcus influenced the decrease of the ketoconazole susceptibility of M. restricta in the co-culturing condition. Furthermore, our data demonstrated that the significant increased ergosterol content and cell membrane and wall thickness of the M. restricta cells grown in the acidic environment may be the main cause of the altered azole susceptibility of the fungus. Overall, our study suggests that the interaction between Malassezia and Staphylococcus influences the antifungal susceptibility of the fungus and that pH has a critical role in the polymicrobial interaction in the skin environment.

• Journal of the Korean GEO-environmental Society
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• v.18 no.12
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• pp.37-45
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• 2017

Structural instability and damage are caused by frost heave during the winter when atmospheric temperature maintains below $0^{\circ}C$. Frost heave is the most representative engineering characteristics of frozen ground and there are various frost susceptibility criteria. Frost susceptibility criteria can be roughly divided into three categories. First, frost susceptibility is determined from particle size distribution, which is practically useful and many countries are adopting. In this paper, several particle size distributions (PSDs) are applied to the frost susceptibility criteria but PSD seems to be not enough to determine whether soils are frost susceptible. Second, it is judged from laboratory frost heave testing results. Laboratory frost heave tests were performed with newly developed thermal controlled triaxial cell and the reliability of frost susceptibility criteria is evaluated. New testing apparatus and method are suitable to meet the existing frost susceptibility criteria. Third, it is compositive frost susceptibility criteria envelope including the particle size distribution, soil classification, and frost heave test. The compositive frost susceptibility criteria envelope should be supplemented based on additional data on various soil types.