• Journal of environmental and Sanitary engineering
• /
• v.22 no.4
• /
• pp.105-117
• /
• 2007

The research was conducted based on the 1012 cases questionnaire for the purpose of to evaluate the change effect of university student's consciousness and behavior before and after lecture on environmental problems. And this questionnaires were performed with self-administered by the university student who made a application for liberal arts related to environmental subjects. The results were as follows. According to the analysis results the most students responded that the most serious problem of environmental pollution before the lecture on environmental education was a genetic modified organism(3.64/4.00), but the most serious problem of environmental pollution was changed to the topic of water pollution(3.96/4.00) after the lecture on environmental problem. And also according to the analysis results dributed by gender were that boy students show a higher concerning(170%) than that of girl students(150%). The most good results obtained after lecture on environmental problem were water pollution(23.0%), air pollution(11.5%), waste material pollution(10.9%), food additives (10.0%), genetic modified organism(8.0%), endocrine disrupter(7.5%), respectively. And according to the analysis results distributed by a grade were that the concerning of a low grade(freshman, sophomore)were higher than that of a high grade(junior, senior) in the topic of water pollution, air pollution, waste material pollution. But there were high level of awareness on the topic of food additives, genetic modified organism, endocrine disrupter to the all students(freshman to senior). And according to the analysis results distributed by a major field of study were that students who major in art & athletics, liberal art and etc(public health) were show a deep concerning than that of science & engineering. Finally, the environmental education during the university class were effectively contribute to increase the awareness of the seriousness of environmental pollution problem(8.2%) and also contribute to the practical life after class also increase their consciousness of environmental problem(59.8%).

• Korean Journal of Materials Research
• /
• v.14 no.9
• /
• pp.676-681
• /
• 2004

In-situ observation in SBM on the microfracture behavior of coating layer was performed for GA steel sheets that have various Fe contents and thickness of coating layer. In case of cross sectional side of coating layer that was in a tensile stress state during bending, fine perpendicular crack pre-induced during galvannealing grew and propagated rapidly toward the coating surface with the increase of strain. And then it grew and propagated along the ${\Gamma}/Fe$ matrix interface, and combined with the nearest another perpendicular crack. Consequently, flaking occurred. The more Fe content and thickness of coating layer increased, the more average crack interval and flaking resistivity increased. Exfoliation was little observed at coating surface in a tensile stress state.

• Journal of Korean Society of Steel Construction
• /
• v.9 no.2 s.31
• /
• pp.259-267
• /
• 1997

Wind tunnel test results and their interpretations focused on the behavior of girder, which were performed to study the aerodynamic stability of a self-anchored suspension bridge with lateral sag of main cable, are presented in this paper The shape of the girder which has the best aerodynamic stability was selected based on the section model test under uniform and turbulent flow conditions. Good performance of the selected section was confirmed in the full bridge model test. Measured flutter derivatives are presented for further study. Buffeting response was investigated to check the fatigue problem and serviceability of the bridge but it was found to be acceptable from the engineering point of view. Even though the drag coefficient of the girder had high value, the amplitude of the lateral vibration was found to be very low. This may be due to the restraint provided by the lateral sag of the cables.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.21 no.5
• /
• pp.780-790
• /
• 1997

In this study, the stress-strain relations of steels have been calculated as a function of microstructural morphologies of each phase by use of FEM program(i.e. ABAQUS). The mechanical behavior of low carbon steels is affected by the microstructural factors such as yield ratio, volume fraction, shape and distribution of each phase and so on. The effects of shape, volume fraction and yield ratio of each phase on the mechanical behavior were analyzed by using unit cell and whole specimen size models. Results obtained are summarized as follows. As the yield ratio of hard phase to that of soft phase and volume fraction of hard phase were increased, stress level of flow curves were increased. It was found that in whole specimen size model, as the particle size was decreased, higher stress level was shown. Lastly the relationship between microstructure and tensile properties was examined by using the steels with various microstructural morphologies.

• Proceedings of the KSME Conference
• /
• 2001.11a
• /
• pp.117-122
• /
• 2001

For two kinds of 25Cr-20Ni stainless steels, SUS310J1TB TB and SUS310S with and without a small amount of Nb and N, creep behavior has been studied in a stress and temperature range from 147 to 392MPa and from 923 to 973K with a special reference to tertiary creep. The average creep life of SUS310J1TB was about 100 times longer than that of the SUS310S. The apparent activation energy for the initial creep rate was 330 kJ/mol in SUS310J1TB, while that of the SUS310S was 274 kJ/mol in a power law creep region and 478 kJ/mol in a region of power law breakdown (PLB). The activation energy for SUS310S below PLB is close to the that for self-diffusion. When compensating for the temperature dependence of the Young's modulus and the omega value, it was found that the apparent activation energy for SUS310J1TB was reduced to the activation energy for diffusion of chromium atom in a gamma steel. The stress exponent of SUS310S was about 12 above PLB and 5.1 in a power law creep region. Notwithstanding that the creep condition for SUS310J1TB was in a power law creep region, its stress exponent was 8.3 larger than that of SUS310S corresponding to the same creep conditions. This was ascribed to the presence of fine precipitates in SUS310J1TB.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.36 no.5
• /
• pp.517-521
• /
• 2012

Carbon nanotubes (CNTs) have been regarded as a promising material for the fabrication of flexible conductors such as transparent electrodes, flexible heaters, and transparent speakers. In this study, a multiwalled carbon nanotube (MWCNT) film was deposited on a polyethylene terephthalate (PET) substrate using a spraying technique. MWCNTs were dispersed in water using sodium dodecyl sulfate (SDS). To evaluate the effect of the weight ratio between SDS and MWCNTs on the electromechanical properties of the film, direct tensile tests and optical strain measurement were conducted. It was found that the CNT film hardly affected the mechanical behavior of CNT/PET composite films, while the electrical behavior of the CNT film was strongly affected by the SDS concentration in the CNT film. The electrical resistance of CNT/PET films gradually increased with the strain applied to the PET substrate, even up to a large strain that ruptured the substrate.

• Journal of Technologic Dentistry
• /
• v.22 no.1
• /
• pp.69-78
• /
• 2000

The microstructure and corrosion behavior of commercially dental casting gold alloys were investigated to clarify the effect of burn-out temperature and cooling rate. In the case of water quenching after casting, only the αphase, which is typical dendritic microstructure of golda alloy, was detected. However, the precipitates along the grain boundary were detected only at the slow cooling rate and they increased inversely proportional to the burn-out temperature. This might be due to the time difference which solute atom could diffuse. EPMA and SEM results also demonstrated that the precipitate should be lamellar structure consisted of Ag rich phase(${\alpha}_1$) and Cu rich phase (${\alpha}_2$). In terms of corrosion, the galvanic coupling was formed due to the difference of composition between precipitates and matrix at the slow cooling rate. In the case of water quenching, the critical current density($i_p$) which indicate the degree of corrosion was lowest at $650^{\circ}C$ and below the burnout temperature, $i_p$ increased with it because of the effect of grain boundary segregation. But above the temperature, $i_p$ increased with it. This may be due to the strain field effect by residual thermal stress.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.37 no.2
• /
• pp.177-189
• /
• 2011

Women starts to make up after high school graduation. They have low economic power. But they select cosmetics by themselves and have high demand. Therefore, they can be major customers of low-priced cosmetics and it can be regarded as independent cosmetics market. Thus, this study analyzes the purchasing propensity of lowpriced cosmetics in female undergraduates, who are main targets of low-priced cosmetics, satisfies the more customers desire through further segmenting the targets, suggests a continuous developmental plan for low-priced cosmetics through securing potential customers and segmenting market, and analyzes and typologizes female undergraduates lifestyle. The aim is to grasp the actual condition of using the low-priced cosmetics and the satisfaction with purchase, and to utilize it as basic date of inducing right consumption culture of female undergraduates. For this study, 305 reliable questionnaires are analyzed from the total 320 questionnaires and spss win 15.0 program was used. The results were as follows. About 90.1 percent of female undergraduates had experience using low-priced cosmetics and standard of priority selection was the quality of low-priced cosmetics. The main reason not to use was low price image.

• Archives of design research
• /
• v.18 no.3 s.61
• /
• pp.181-190
• /
• 2005

Although the national government prepares and implements planning for securing various services and facilities based on the needs of welfare centers for leisure of the aged according to the increase of life expectancy. These efforts are still beyond the satisfaction for the needs of the aged. These efforts are only polling on in terms of the increase in quantity, and so therefore there is total lack of high level of welfare facilities for the aged with regard to the consumers' characteristics and behavior attitudes. Under these considerations, this study aims at investigating through indoor space check list, the reality of whether the present welfare centers for the aged are designed with the application of the characteristics and behavior attitudes of the aged to the indoor space. The results of this study are going to be utilized as basic materials for future designs that may consider the behavioral attitudes of the aged and be able to increase their quality of leisure and welfare when building welfare centers for the aged in the future.

• Korean Security Journal
• /
• no.42
• /
• pp.449-468
• /
• 2015

It is important to identify and discuss what the most vial contributions of criminological theories. In the field of criminology, most significant contributions or advancement have been made on the various issues such as age, the integration of structural and procedural level theories, other theoretical integration debates. However, it is hard to find ant systematic study exploring such a contribution in criminological theories. This study, therefore, has a purpose to discuss three most significant contributions to our theoretical understanding of criminal behavior made since 1985. To accomplish the study purpose, this study choose the followed three theoretical contributions; the emergence of life course theory, the revision of social disorganization theory, and the introduction of social structure and social Learning (SSSL) model. The three theoretical works will be introduced and discussed regarding other theoretical integration trends in the body of this study. The conclusion, contribution of this current study has been discussed in the last conclusion and discussion section.