• Structural Engineering and Mechanics
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• v.86 no.5
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• pp.607-619
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• 2023

This study, it was tried to evaluate the asphalt behavior under tensile loading conditions through indirect Brazilian and direct tensile tests, experimentally and numerically. This paper is important from two points of view. The first one, a new test method was developed for the determination of the direct tensile strength of asphalt and its difference was obtained from the indirect test method. The second one, the effects of particle size and loading rate have been cleared on the tensile fracture mechanism. The experimental direct tensile strength of the asphalt specimens was measured in the laboratory using the compression-to-tensile load converting (CTLC) device. Some special types of asphalt specimens were prepared in the form of slabs with a central hole. The CTLC device is then equipped with this specimen and placed in the universal testing machine. Then, the direct tensile strength of asphalt specimens with different sizes of ingredients can be measured at different loading rates in the laboratory. The particle flow code (PFC) was used to numerically simulate the direct tensile strength test of asphalt samples. This numerical modeling technique is based on the versatile discrete element method (DEM). Three different particle diameters were chosen and were tested under three different loading rates. The results show that when the loading rate was 0.016 mm/sec, two tensile cracks were initiated from the left and right of the hole and propagated perpendicular to the loading axis till coalescence to the model boundary. When the loading rate was 0.032 mm/sec, two tensile cracks were initiated from the left and right of the hole and propagated perpendicular to the loading axis. The branching occurs in these cracks. This shows that the crack propagation is under quasi-static conditions. When the loading rate was 0.064 mm/sec, mixed tensile and shear cracks were initiated below the loading walls and branching occurred in these cracks. This shows that the crack propagation is under dynamic conditions. The loading rate increases and the tensile strength increases. Because all defects mobilized under a low loading rate and this led to decreasing the tensile strength. The experimental results for the direct tensile strengths of asphalt specimens of different ingredients were in good accordance with their corresponding results approximated by DEM software.

• Korea journal of population studies
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• v.12 no.2
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• pp.1-21
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• 1989

For the analysis of mortality differentials by socioeconomic factors based on death registration data, we have considered four variables : place of residence, educational attainment, marital status and occupation. The age range adopted were 5 to 64 years of age for place of residence, and 25 to 64 years of age for the other factors. The mortality differentials by socioeconomic variables were clear and in the expected direction: mortality levels among urban residents, better educated groups, and non- agricultural workers were lower than among the other sub- groups. The average mortality level in rural areas is much higher than in urban areas : the rural mortality levels were at least double the urban levels at ages below 40 years, but became smaller after age 40, and no clear differentials by urban I rural residence increased until 1974~76 for the both sexes, but since the then differentials have declined slowley for both sexes. This changing pattern of mortality differentials by place of residence can be explained by historical socioeconomic development : the development generally started in urban areas, and rural areas followed : in the course of socioeconomic development the differences between the death rates in the two areas became smaller and finally the mortality levels in the two areas became nearly the same, as is found in the developed countries nowadays. The inverse relationships between mortality and educational level became stronger between the periods 1970~72 and 1984~86, but showed the same atterns of mortality differentials in both period : larger differences among the younger age groups, and for males, than among the older age groups, and for females. The increasing mortality differentials in the fourteen-year period between 1970~72 and 1984~86 were caused by inadequate living standards of the non- educated, whose proportion in the total population, however, dropped sharply during that period. Also, the much lower proportions of low - educated groups or of persons with no formal education among males than females helped to establish the clearly pronounced differentials. The mortality differentials by marital status in Korea showed the usual pattern : the mortality rates of the married in each age and sex group were clearly lower than those of others during the fourteen-year period between 1970~72 and 1984~86. In Korean society which remotes universal marriage, the never married recorded especially high death rates, presumably mainly because of ill - health, but also possibly because of the stigma attached to celibacy. However, the mortality differentials by marital status changed with the changes in the proportionate distribution by marital status during the period : the differences between the death rates of the married and never married groups became smaller, the proportion of the never married group increased : in contrast, the differences between mortalities of the married and widowed / divorced / separated groups widened, with the decrease in the proportion of the later group ; this tendency was perticularly marked for females. Occupational groups also showed clear mortality differences : among four occupational groups mortality of males was highest among agricultural workers and lowest among 'professional, admi-nistrative and clerical workers, However, when the death rates were standardized by educational level, the death rates by occupation in age group 45~64 years were nearly the same (excet for the mixed group consisting of unemployed, students, military servicemen and unknown). Therefore, the clear mortality dfferentials by occupation in Korea resulted mainly from the differences in educational level between different occupation groups. Since socioeconomic characteristics are related to each other, the net effect of each variable was examined. Each of the three variables - ducational level, marital status and urban / rural residence affected significantly Korean adult mortality when the effects of the other variables were controlled. Among the three variables educational level was the most important factor for the determination of the adult mortality level. When male's occupation was added to the above three variables, the effects of occupation on adult mortality were notably smaller after control for the effects of the other three variables while the net effects of these three variables were nearly the same irrespectively whether occupation was included or not. Thus, the differences in educational level (mainly), place of residence and marital status bring out the clear differences in observed mortality levels by occupation.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.20
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• pp.23-62
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• 2003

The Law amending the Conflict of Laws Act of the Republic of Korea ("Korea"), which had taken two years to prepare, was promulgated on April 7, 2001 and finally took effect as of July 1, 2001. Accordingly, the old earlier Conflict of Laws Act which was called "Seoboesabeop" in Korean ("Prior Act"Old Act) was replaced by the new Conflict of Laws Act called "Gukjesabeop" in Korean ("New Act"). In fact the Old Act Prior Act was promulgated in 1962, but it was regarded as outdated from the moment of its promulgation. However, since the Old Act because it was modeled after the chapter of the Private International Law of the Einfuehrungsgesetz zum Buergerlichen Gesetzbuch (EGBGB) of the Federal Republic of Germany ("German PIL") and the Japanese Private International Law ("Japanese PIL") which had been promulgated toward the end of the 19th century., the Old Act was viewed as outdated from the moment of its promulgation. As a result of the drastic change of the environment for international trade of which that has taken took place in parallel with the global information technology revolution on a global basis, the scope of issues to be addressed which should be resolved by the conflict of laws principles has been remarkably expanded, and various new issues of an entirely which are quite new in its type and nature have arisen been raised. In the field of conflict of laws in its narrow sense, a revolution or crisis of the traditional conflict of laws has been brought about by the advent in the United States rise of a the new methodology for of the conflict of laws, of the United States of America and in the process of overcoming the such crisis the conflict of laws of the European continent has undergone substantial changes such as the diversification of the connecting principles, the expansion of the principle of party autonomy and the consideration of the value of the substantive law to protect socio-economically weaker parties of. The Prior Act, which was based on However, with the mechanical connecting principles and contained various outdated the inappropriate provisions, the Old Act could not cope with the issues raised by the internationalization and globalization of the Korean society. Furthermore In addition, the Old Act Prior Act was regarded as insufficient in that it lacked rules on international jurisdiction to adjudicate, or international adjudicatory jurisdiction, whereas the expectation of the public was that the Conflict of Laws a Act should function as the "Basic Law of the International Legal Relationships"encompassing rules on international jurisdiction given the increase of international disputes. Furthermore the private international law has also attracted more attention from the Korean At the beginning of the new Millennium, thanks to the promulgation of the New Act, I believe that Korea has succeeded in achieving the modest goal of reflecting in the its codification substantial parts of the major developments of the private international law which the leading advanced continental European countries had achieved during the last century. The New Act has followed the approach of the traditional conflict of laws of the European continent. It is a product of the efforts to eliminate the then existing problems of the Prior Old Act and to adapt the Korean private international law regime to the standard of international conventions and national laws of advanced countries. Unlike the Prior Old Act which was heavily dependent upon the prior Japanese PIL and the prior German PIL, the New Act has been prepared by taking into full account the Rome Convention, the Swiss PIL, the new German PIL which took effect in 1986 and various conventions adopted by the Hague Conference. Therefore, the New Act has substantially reduced dependence upon the Japanese PIL and the German PIL, and has gained relatively greater universal validity. The fact that the New Act expressly declares that the determination of international jurisdiction is a matter of conflict of laws is a clear sign that it has departed from the German tradition which confines the conflict of laws principles to choice of laws rules, and moved toward a broader and more practical approach widely accepted in the area of conflict of laws. It is hoped, and I am personally confident, that the New Act will be able to achieve its intended objectives in the 21st century as the basic law for the ever-increasing legal relationships with a foreign element.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.4
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• pp.100-108
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• 2016

The climatic index for tourism(CIT) has recently been advanced, which includes complete human energy balance models such as physiological equivalent temperature(PET) and universal thermal climate index(UTCI). This study investigated human thermal sensation and comfort at Woljung-ri Beach, Jeju, Republic of Korea, in spring and summer 2015 for landscape planning and design in beach areas. Microclimatic data measurements and human thermal sensation/comfort surveys from ISO 10551 were conducted together. There were 869 adults that participated. As a result, perceptual and thermal preference that consider only physiological aspects had high coefficients of determination($r^2$) with PET in linear regression analyses: 92.8% and 87.6%, respectively. However, affective evaluation, personal acceptability and personal tolerance, which consider both physiological and psychological aspects, had low $r^2s$: 60.0%, 21.1% and 46.4%, respectively. However, the correlations between them and PET were all significant at the 0.01 level. The neutral PET range in perceptual for human thermal sensation was $25{\sim}27^{\circ}C$, but a PET range less or equal to 20% dissatisfaction, which was recommended by ASHRAE Standard 55, could not be achieved in perceptual. Only PET ranges in affective evaluation and personal tolerance affected by both aspects were qualified for the recommendation as $21{\sim}32^{\circ}C$ and $17{\sim}37^{\circ}C$, respectively. Therefore, the PET range of $21{\sim}32^{\circ}C$ is recommended to be used for the human thermal comfort zone of beach areas in landscape planning and design as well as tourism and recreational planning. PET heat stress level ranges on the beach were $2{\sim}5^{\circ}C$ higher than those in inland urban areas of the Republic of Korea. Also, they were similar to high results of tropical areas such as Taiwan and Nigeria, and higher than those of western and middle Europe and Tel Aviv, Israel.

• Journal of Korean Philosophical Society
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• v.130
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• pp.219-246
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• 2014

Do the particular good and the common good stand in relation of opposition or superiority each other? With regard to this question, some argue that the relevant Thomas texts reveal the superiority of the common good over the particular good, while others argue for the superiority of the particular good. The argument of this articles is, however, that closer examination of texts shows that Thomas Aquinas seeks to the unity of the common good and the particular good instead of seeing the conflict between them. It is true that Thomist moral and political theory emphasizes the value of the individual, but it should be noted that for Thomas the individual as individual does not exist, but shares specific formal determination with other members of the same species and, therefore, is the individualized, concrete universal. Good, meanwhile, means perfection which each being pursues and a thing is called good in the absolute sense when it actualizes its potentialities as a whole. An individual person is said to pursue only partial good, if it only seeks its perfection as an individual. The nature of individual person should be fully realized only in and through the community pursuing the common good. But the aim of living together which is rooted in the nature of human being as a rational being is for its members to live virtuously. The political community is said to try to bring its individual members to perfection, since the virtues are what renders human beings and their acts good. In this sense the particular good of the individual person is achieved through the pursuit of the common good and the common good is realized through the pursuit of the particular good so that they coincide each other. But this unity remains imperfect, when it would not be rightly ordered to its due end which is non other than the highest good, that is God. Accordingly the goodness of the human being in an absolute sense lies in the unity of the particular good and the common good rightly oriented towards the highest good, which is also called common good which every being pursues.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.182-193
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• 2022

Purpose: By measuring and evaluating the risk of biodiesel through non-volatile residue (NVR) and flash point and explosion limit measurement at a specific temperature according to ASTM test standards, the risk of chemical fire causative substances is identified and a universal evaluation method By derivation and securing the risk-related data of the material, it can be used for the identification and analysis of the cause of the fire, and it can be applied to the risk assessment of other chemical substances Method: In order to measure the risk of biodiesel, it was measured using the non-volatile residue(NVR) measurement method, which measures how much flammable liquid is generated at a specific temperature. Heating was tested by applying KS M 5000: 2009 Test Method 4111. In addition, the flash point was measured using the method specified in ASTM E659-782005, and the energy supply method was measured using the constant temperature method. In addition, the explosion limit measurement was conducted in accordance with ASTM E 681-04 「Standard test method for concentration limits of flammability of chemicals(Vapors and gases)」 test standard. Result: As a result of checking the amount of combustible liquid by the non-volatile residue (NVR)measurement method, the non-volatile residue(NVR) of general diesel when left at 105±2℃ for 3 hours was about 30% (70% of volatile matter) and about 4% of biodiesel. In addition, similar results were obtained for the non-volatile residue(NVR)heating temperature of 150±2℃, 3 hours and 200±2℃ for 1 hour, and white smoke was generated at 200℃ or higher. In addition, similar values were obtained as a result of experimentally checking the explosion (combustion) limits of general diesel, general diesel containing 20% biodiesel, and 100% biodiesel. Therefore, it was confirmed that the flammability risk did not significantly affect the explosion risk. Conclusion: The results of this study suggested the risk judgment criteria for mixtures through experimental research on flammable mixtures for the purpose of securing the effectiveness, reliability, and reproducibility of the details of the criteria for determining dangerous substances in the existing Dangerous Materials Safety Management Act. It will be possible to provide reference data for the judgment criteria for flammable liquids that are regulated in the field. In addition, if the know-how for each test method is accumulated through this study, it is expected that it will be used as basic data in the research on risk assessment of dangerous substances and as a basis for research on the determination of dangerous substances.