• Journal of the Microelectronics and Packaging Society
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• v.18 no.4
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• pp.33-38
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• 2011

The p-type $(Bi_{0.2}Sb_{0.8})_2Te_3$ powers were fabricated by mechanical alloying and hot-pressed at temperatures of $350{\sim}550^{\circ}C$. Themoelectric properties of the hot-pressed $(Bi_{0.2}Sb_{0.8})_2Te_3$ were characterized as a function of the hot-pressing temperature. With increasing the hot-pressing temperature from $350^{\circ}C$ to $550^{\circ}C$, the Seebeck coefficient and the electrical resistivity decreased from 237 ${\mu}V/K$ to 210 ${\mu}V/K$ and 2.25 $m{\Omega}-cm$ to 1.34 $m{\Omega}-cm$, respectively. The power factor of the hot-pressed $(Bi_{0.2}Sb_{0.8})_2Te_3$ became larger from $24.95{\times}10^{-4}W/m-K^2$ to $32.85{\times}10^{-4}W/m-K^2$ with increasing the hot-pressing temperature from $350^{\circ}C$ to $550^{\circ}C$. Among the specimens hot-pressed at $350{\sim}550^{\circ}C$, the $(Bi_{0.2}Sb_{0.8})_2Te_3$ hot-pressed at $500^{\circ}C$ exhibited the maximum dimensionless figure-of-merit of 1.09 at $25^{\circ}C$ and 1.2 at $75^{\circ}C$.

• Journal of Internet Computing and Services
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• v.18 no.4
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• pp.109-119
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• 2017

This paper is to analyse empirically using the data collected from Korea portal Naver's ad management system and show online ad platform may not be two-sided market. It is aim of this study to propose the appropriate approach to define the market, based on the empirical result. Here are two research questions to be reviewed. First, is there any consistency between business model of search advertising and definition of two-sided market which Rochet-Tirole proposed in 2006? Second, do indirect network externalities exist significantly in search advertising market? if so, this study is going to estimate the level of it through empirical measurement. Based on Luchetta's paper which suggested that google may be one-sided market, it performed the correlation & regression analysis to prove his suggestion. The result is that online search advertising costs increased by more than 50 won when advertisers increased by one unit. However, there was no significant correlation and regression between the search frequency and online search advertising cost. It means that there is little possibility to identify two-sidedness in online search advertising service(market) because of no(or little) indirect network externalities which are a necessary condition for two-sided market. This result has three implications, such as the availability to adapt traditional market definition tools to online search advertising market, the possibility enhancement to find the fundamental competition elements in defined market and promotion of the powers of persuasion in competitive market reality. It is significant that the gap between legal scholars including regulatory practitioners and economists can be overcome to some extent. who have shown the different perspective on the two-sided market.

• Journal of Life Science
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• v.20 no.9
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• pp.1385-1393
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• 2010

Three mold strains, Aspergillus oryzae (AOFAG), Aspergillus kawachii (AKFAG), and Monascus purpureus (MPFAG) were used for fermentation of Angelica gigas Nakai powder. The contents of polyphenolic compounds, flavonoids, minerals, decursin and decursinol angelate and the activities of DPPH (${\alpha},{\alpha}'$-diphenyl-$\beta$-picrylhydrazyl) free radical scavenging, reducing power, and tyrosinase were measured. The highest contents of phenolic compound and flavonoid were NFAG at 2.78% and MPFAG at 1.18%, respectively. Major minerals were K, Mg, Fe, Na and Ca. Decursin and decursinol angelate were the major ingredients of Angelica gigas according to HPLC analysis. Decursin area was higher in all fermented Angelica gigas than in NFAG. The activities of free radical scavenging and tyrosinase were stronger in all fermented Angelica gigas than NFAG. However, the Fe/Cu reducing powers were stronger in NFAG than all fermented Angelica gigas. Overall, these results may provide the basic data needed to understand the biological activities and chemical characteristics of Angelica gigas fermented by mold for the development of functional foods.

• Journal of The Korean Association For Science Education
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• v.32 no.5
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• pp.866-878
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• 2012

The Natural Science High School is specialized in vocational education or training related to natural sciences such as biology or chemistry. Therefore, natural science high school students are expected to possess a high level of science learning motivation. This study aims to explore natural science high school students' level and structure of science learning motivation by comparing students in general high school. One hundred ninety three students from a natural science high school and 208 from a general high school participated in this study. We administered a questionnaire that consisted of seven science motivation components: 1) career motivation; 2) science grade motivation; 3) understanding the relevance of scientific knowledge; 4) need for learning science; 5) self-determination; 6) self-efficacy; and 7) attitudes toward science class. We employed independent t-test, path analysis, bivariate correlation, and stepwise multiple-regression for the statistical analyses. Our findings illustrated that the natural science high school students' levels on all seven variables were significantly lower than the general high school students.' The path analysis illustrated that career motivation and science grade motivation had relatively stronger influence on self-determination and self-efficacy in the natural science high school student sample than in the general high student sample. The explanatory powers of four independent variables (career motivation, science grade motivation, understanding the relevance of scientific knowledge, and need for learning science) predicting self-determination and self-efficacy were 30% higher in the natural science high school student sample than in the general science high student sample. These results suggested that natural science high school students' science learning motivation may be easier to change by extrinsic motivations such as career and science grade motivation.

• KDI Journal of Economic Policy
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• v.14 no.4
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• pp.79-106
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• 1992

This study analyzes the determinants of wage premium, defined as the excess of actual wage rate over opportunity wage, for the average worker in a Korean bargaining unit. Average wage premium of a firm is decomposed into quasi-rent per worker and rent-sharing rule. Per capita quasi-rent, representing a firm's ability to pay, is defined as the difference between sales revenue and the opportunity cost of mobile factors, divided by the number of employees. Rent-sharing rule, a measure of workers' bargaining power, is defined as the average wage premium divided by the per capita quasi-rent. Empirical results show that the differences in wage premium among Korean bargaining units are much better explained by the differences in quasi-rent than by the differences in bargaining power. Also, comparing the results of 1986 with those of 1988 show that the wage settlement mechanism in 1988 was not quite different from that of 1986, in spite of the drastic change in industrial relation system in 1987. It may simply yield higher opportunity wages, by raising the bargaining power of overall workers. The tendency of Korean labor market in 1988 to show a dual structure of high & low wage premium sectors, is not due to the fact that the differences in bargaing powers across firms tend to expand, but to the fact that unions tend to reduce the wage differences among the workers within an enterprise by pursuing more equal distribution of total wage premium. Hence, the policies for reducing the wage differentials across firms should focus on rent-regulating industrial policies, e.g. eliminating monopoly rents by deregulation.

• The Korean Journal of Air & Space Law and Policy
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• v.20 no.2
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• pp.159-234
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• 2005

As so clearly have been demonstrated in the Gulf War and Iraq Freedom Fight, along with the civilian space exploration and development, the 'militarization' of aerospace technology and the 'battlefield-worthiness' of space are becoming more and more at issue. Korean peninsula, the last major theatre where the 4 world powers' national interests stand face to face, no doubt is in dire need for understanding and organizing necessary legislations for establishing national security from any space threats, such as satellite imaging, as well as countering against such threats. Compare to United States, Japan and China that have already declared the national security as the purpose of the space development, and equipped themselves with necessary legislations, Korea's legislations fall short of fully appreciating and effectively responding to the significance of military use of outer space and its control. This article will review legislations of leading countries' of space law and space technologies from two different perspectives. After briefly summarizing the problems of Korea's current legislations, particularly with the National Space Development Act (proposal), drafted by Ministry of Science and Technology, in mind, this article reviews and offers certain legislative directions to which Korea should pursuel for national security of outer space.

• Journal of the Economic Geographical Society of Korea
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• v.23 no.3
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• pp.312-333
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• 2020

Korea-Africa relations date back to the period of independence of African countries. During this time, the ties between Korea and Africa has passed through stagnation, inconsistencies and weak diplomatic exchanges. Recently, Korea began to refocus its efforts towards Africa in order to revitalize their relations. This paper examines Korea's public diplomacy strategies towards Africa and how its various strategies are working in the interest of Korea as well as Africa. The study shows that Korea's renewed interest in Africa is primarily driven by the security threat from North Korea and the need to diversify its market for industrial goods as well as energy sources. The latter motives override Korea's interest in the continent. These motives are not at variance with those pursued by large powers like the US and China in Africa. Furthermore, the paper shows that Korea is employing a mixture of public diplomacy instruments in Africa with varied outcomes. Economic linkages between Korea and Africa are on an upward trajectory since the late 2000s. In order to build sustainable relations, the paper provides a number suggestions with far-reaching implications on Korea's public diplomacy towards Africa in the future.

• Preventive Nutrition and Food Science
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• v.19 no.2
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• pp.115-123
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• 2014

In the current study, wheat flour was mixed with high quality cassava flour (HQCF) in several ratios: 90:10, 80:20, 70:30, and 60:40, and used to prepare 10%, 20%, 30%, and 40% National Root Crops Research Institute (NRCRI) cassava bread, respectively. 100% wheat bread was prepared as a control (100% wheat bread). Five bread samples were prepared per group. Antioxidant assays [i.e., 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging assay, reducing power assay] revealed that the bread samples had considerable antioxidant capacities. Substitution of wheat flour with HQCF at various concentrations resulted in dose dependent decreases in the mineral and protein contents of the resulting bread samples. The crude fiber content of the bread samples was minimal, while the carbohydrate content of the bread samples ranged from 43.86% to 48.64%. A 20% substitution of wheat flour with HQCF yielded bread samples with a general acceptability that was comparable to that of 100% wheat bread. The mean bacteria counts of the bread samples ranged from $2.0{\times}10^3CFU/mL$ to $1.4{\times}10^4CFU/mL$, while the fungal counts ranged from 0 CFU/mL to $3{\times}10^3CFU/mL$. There was a positive correlation between the DPPH antioxidant activities and the reducing powers of the bread samples ($R^2=0.871$) and a positive correlation between the DPPH antioxidant activities and the flavonoid contents of the bread samples ($R^2=0.487$). The higher microbial load of the NRCRI cassava bread samples indicates that these bread samples may have a shorter shelf life than the 100% wheat bread. The significant positive correlation between total flavonoid content and reducing power ($R^2=0.750$) suggests that the flavonoids present in the lipophilic fractions of the bread samples could be responsible for the reductive capacities of the bread samples.

• KOMUNHWA
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• no.68
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• pp.25-39
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• 2006

This article attempts to define identity, role and functions of a university museum and to suggest specialization of the university museum in the perspective of culture, arts, and science. A university museum is defined as a center for the service of the university community and its development which acquires, researches, communicates, exhibits and educates, for purposes of eduinfotainment,29 material evidence of people and their environment. The target user of the today's university museum are not only professors, students, university workers, but also university neighbourhood such as the related professionals, patrons, parents, school children and villagers. A multi-dimensional and multi-purpose university museum can be established and managed in a real world and / or a cyber world in the perspective of culture, arts, and science. Based on a ubiquitous system30 in a cyber world vis-a-vie a real world, the university museum can be easily utilized by users anywhere, anytime and any device. In order to specialize the university museum in the perspective of culture, arts and science, it is desirable that the university museum director with the CEO of the university community promote the specialization of the university museum based on philosophy and strategies of university community management after they definitely evaluate the components and resources of the university museum such as human powers, museum collections, organizational, technological, capital, spacial and symbolic resources, The specialization of the university museum should be projected and executed in the direction of maintaining the typical scope of museum activities and managing the effective museum management. Specializing the university museum in the perspective of culture, arts, and science can contribute not only to establish the identity of the university community and to perform role and functions of the university museum but also to encourage academic development, to revaluate the brand of the university community and to promote the marketing for the university.

• Journal of muscle and joint health
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• v.6 no.2
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• pp.253-277
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• 1999

Patients with chronic disease have various treatment patterns because it shows a progressive degenerative feature. Especially various physical and emotional problems of the rheumatoid arthritis patients leave them shopping around various types of treatment. According to previous studies, over 70% of patients with arthritis experienced the traditional oriental medicine or folk remedies simultaneously with medical treatment within one year after the onset of disease. The purposes of this study are 1) to compare the patterns of treatment-seeking behaviors between Korean arthritis patients and Americans ; and 2) test two models of treatment-seeking behaviors by path analysis, one for early treatment-seeking behavior model(ETBM) and the other is chronic treatment-seeking behavior model (CTBM) in Korean sample. The interview survey was performed to 133 RA patients with structured questionnaire at out-patient clinic or public health center. Patients characteristics such as age, duration of disease were similar in two countries except higher educational background in Americans. There were no patients using only alternative therapies or no medical treatment in the US. Most of the American patients have chosen both medical treatment and alternative therapy, while the Koreans less than American. In Korea, combined treatment group usually consists of the people who are younger, more educated and higher economic status than the characters of other groups in early or chronic stages. In early stage, they tend to have strong belief of curing from the disease, satisfy the relationship with their physicians and comply with direction of the medical professional. The paths of two models were explained by 70% in ETBM and 33% in CTBM. When the models were modified, almost all paths of the CTBM were the same as the previous one, but direct determinant factor was changed from the relationship with physicians to the lay referral system in chronic model. These two models' explanation powers became 94% and 88%, respectively. The attitude or perception of disease, lay referral system and the relationship with medical personnel are the main determinants of treatment-seeking behaviors.