• Journal of the Korean Ceramic Society
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• v.42 no.2 s.273
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• pp.104-109
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• 2005

To study the role of PbO as the buffer layer, Pt/PZT/PbO/Si with the MFIS structure was deposited on the p-type (100) Si substrate by the r.f. magnetron sputtering with $Pb_{1.1}Zr_{0.53}Ti_{0.47}O_3$ and PbO targets. When PbO buffer layer was inserted between the PZT thin film and the Si substrate, the crystallization of the PZT thin films was considerably improved and the processing temperature was lowered. From the result of an X-ray Photoelectron Spectroscopy (XPS) depth profile result, we could confirm that the substrate temperature for the layer of PbO affects the chemical states of the interface between the PbO buffer layer and the Si substrate, which results in the inter-diffusion of Pb. The MFIS with the PbO buffer layer show the improved electric properties including the high memory window and low leakage current density. In particular, the maximum value of the memory window is 2.0V under the applied voltage of 9V for the Pt/PZT(200 nm, $400^{\circ}C)/PbO(80 nm)/Si$ structures with the PbO buffer layer deposited at the substrate temperature of $300^{\circ}C$.

• Journal of the Korea Institute of Building Construction
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• v.20 no.5
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• pp.471-480
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• 2020

Although the domestic industrial accidents have been decreased gradually, deaths in the construction sites have been occupied 49.9 percent of the total industry and deaths from fall accident have been accounted for 59.7 percent of the construction industry. In order to prevent fall accident, various safety activities and policy have been carried out. However, the impact on the domestic construction industry was inadequate. On the other hand, in advanced countries, such as the United States, Japan, EU, and Singapore Industrial accidents have been lower than domestic industry due to safety activities, the regulations and policies appropriate for each country's situation. In this study, we compare the major points of the Industrial Safety and Health Act in developed countries with those in South Korea to reduce the number of falls, and propose a revision. As a result of conducting research, three revisions have been proposed as 1) Enhance standards for fall height, 2) Improvement of upper safety rail height on guardrail, 3) Revision and research on Horizontal Sarety bar attachment system. This study will be utilized as a basic study for the analysis of cases in advanced countries.

• The Journal of the Convergence on Culture Technology
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• v.5 no.3
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• pp.147-154
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• 2019

Baseball was first introduced in Korea by American Gillette, who was the general manager of the YMCA in the late Joseon Dynasty. There are many discussions about the timing of the first baseball game in Korea, but it has yet to be sorted out. But what is certain is that baseball was introduced directly from the after 1903, when the first Korea YMCA, the Hwang seong Christian Youth Association, was founded. Gillett studied at Springfield YMCA International Training School in the United States from 1900 to 1901. The school is where Gulick worked as a teacher, who actively embraced strong Christianity from Britain and laid the foundation for the YMCA project in the United States. Therefore, Gillett was influenced by this Muscular Christianity, and the reason behind the introduction of baseball in our country is the same Muscular Christianity idea. Gillett, the manager of the YMCA in Korea, has developed various sports projects in Korea based on this Manager idea. It also helped the Korean people, who have been under Japanese colonial rule since 1905, to strengthen their bodies and minds and It helped the independence movement of Koreans. These specific and practical examples are YMCA baseball team active and the 105-member incident.

• The Korean Journal of Archival Studies
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• no.48
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• pp.45-92
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• 2016

Corporations report their economical, environmental, social influences and achievements through sustainability reports. Apart from the financial reports, which are subject to legal restrictions, sustainability reports inform non financial achievements of a corporation, thus the reliability of the information is solely dependent on the corporation itself. The current sustainability reports are of types that cannot include proof or source of the index data, thus they are tended to be regarded as means of publicity. The reliability of the reports is often questioned. This research applied the concept of Evidence-Based Accountability, which will allow the confirmation of accountability through records including contents and context of the tasks. Evidence-Based Accountability means producing and accumulating witness records of actions, then managing the records as usable information and use them as accountability information. Index data from sustainability reports of domestic corporations and web based reports of Vodafone was reviewed. Measures to link task records as proof of index data was studied. To make this possible, record production and acquisition system was redesigned in order to secure required records as evidence. Linked build-up of SR system and RMS was proposed. The proposed system will allow collection and management of records as SR accountability information, and provide the data when necessary. Also, corporate infrastructure was proposed. This infrastructure will build a professional records management system in stages, through organizational system and regulations. Cooperation of staff in this infrastructure will support reliable corporate accountability.

• (The)Korea Educational Review
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• v.23 no.3
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• pp.117-142
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• 2017

The purpose of this study is to illustrate Richard Henry Tawney's idea of adult education among traditions of workers' education movement. The workers' education movement can be categorized into two streams. One tradition regards as the workers' education as a part of liberal education. The other tradition regards as it as a tool for social transformation. The former, which emphasizes the importance of liberal education in workers' education, had been developed in connection with the University Extension in England, and had a practical influence through the 'Workers' Educational Association(WEA)' organized by Mansbridge and other intellectuals. The latter, which emphasizes the social transformational function of education, conducted education in a form that is not clearly distinguished from propaganda, through the 'National Council of Labour College(NCLC)'. Tawney demonstrates the idea of adult education that synthesizes these two traditions, and this synthesization is related to his idea on equality. Tawney pursued socialism through democratic and non-violent way. He thought that adult education could contribute to the construction of socialism while at the same time conducting adult education based on liberal education. In other words, adult education based on liberal education, through rational understanding and discussion of the world, can contribute to social transformation. Tawney's idea of adult education provides practical implications for educationalists and educators who want progressive social change, and theoretically enriches educational research on the relationship between social transformation and education.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.2
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• pp.161-173
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• 2019

In this study, the antioxidative and inhibitory activity of tyrosinase and collagenase for the solvent extract and silica column fractions of Artocarpus nitidus were evaluated. The activities were quantified using the 4 parameter logistic. LC/MS analysis showed that the major component of the fractions was polyphenol and the total polyphenol content of the extract was $48.1{\pm}2.6mg\;GAE/g$. The radical scavenging activities ($SC_{50}$) for 1,1-diphenyl-2-picrylhydrazyl of the extract, fraction-1 and fraction-2 were 16.7, 42.0 and $10.1{\mu}g/mL$, respectively. The value for fraction-2 was the closest to ascorbic acid ($1.5{\mu}g/mL$). The tyrosinase inhibitory activity of the extracts and the fractions showed $IC_{50}$ of 64.9, 0.9 and $1.2{\mu}g/mL$, respectively, and overall activity was higher than that of kojic acid ($7.4{\mu}g/mL$) and arbutin ($119.0{\mu}g/mL$). In the experiment by zebrafish embryo, the whitening activity of fraction-2 (27.5%) was higher than that of kojic acid (18.6%), and there was no adverse effect up to $500{\mu}g/mL$ of fraction-2. For the collagenase inhibitory activity, the samples showed $IC_{50}$ of 139.8, 20.6, and $16.8{\mu}g/mL$, respectively, which were competitive to 1, 10-Phenanthroline ($55.4{\mu}g/mL$). The extract and fraction-2 showed $IC_{50}$ of 61.8 and $67.1{\mu}g/mL$ for elastase. These results suggest that A. nitidus extract can be used as a cosmetic material useful for antioxidant, whitening, and prevention of skin aging without adverse effects.

• Korean Journal of Environmental Agriculture
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• v.25 no.4
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• pp.306-315
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• 2006

Two different experiments, adsorption/desorption and runoff by rainfall simulation of four pesticides, such as alachlor, ethalfluralin, ethoprophos and pendimethalin were undertaken their runoff and erosion losses from sloped land and to assess the influence of their properties and environmental factors on them. The mobility of four pesticides and which phase they were transported by were examined in adsorption study, and the influence of rainfall pattern and sloping degree on the pesticide losses were evaluated in simulated rainfall study. Freundlich adsorption parameters (K) by the adsorption and desorption methods were 1.2 and 2.2 for ethoprophos, 1.5 and 2.6 for alachlor, respectively. And adsorption distribution coefficients (Kd) by the adsorption and desorption methods were 56 and 94 for ethalfluralin, and 104 and 189 for pendimethalin, respectively. K or Kd values of pesticides by the desorption method which were desorbed from the soil after thoroughly mixing, were higher than these ones by the adsorption method which pesticides dissolved in water were adsorbed to the soil. Another parameter (1/n), representing the linearity of adsorption, in Freundlich equation for the pesticides tested ranged from 0.96 to 1.02 by the desorption method and from 0.87 to 1.02 by the adsorption method. Therefore, the desorption method was more independent from pesticide concentration in soil solution than the adsorption method. By Soil Survey and Land Research Center (SSLRC)'s classification for pesticide mobility, alachlor and ethoprophos were classified into moderately mobile $(75{\leq}Koc<500)$, and ethalfluralin and pendimethalin were included to non-mobile class (Koc > 4000). Runoff and erosion loss of pesticides by three rainfall scenarios were from 1.0 to 6.4% and from 0.3 to 1.2% for alachlor, from 1.0 to 2.5% and from 1.7 to 10.1% for ethalfluralin, from 1.3 to 2.9% and from 3.9 to 10.8% for pendimethalin, and from 0.6 to 2.7% and from 0.1 % 0.3% for ethoprophos, respectively. Distribution of pesticides in soil profile were investigated after the simulated rainfall study. Alachlor and ethoprophos were leached to from 10 to 15 cm of soil layer, but ethalfluralin and pendimethalin were mostly remained at the top 5 cm of soil profile. The losses of the pesticides at 30% of sloping degree were from 0.2 to 1.9 times higher than those at 10%. The difference of their runoff loss was related with their concentration in runoff water while the difference of their erosion loss must be closely related with the quantity of soil eroded.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.219-225
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• 2007

This study was performed to provide basic ideas as understanding and application for oriental medicinal cuisine (Yak-Sun). To develop medicinal cuisine, it is necessary to grasp the theoretical system. And to develop medicinal cuisine for health enhancement, it is also required not only to consider constitutions but also to suggest the need of knowledge for moderation in terms of regimen along with the theory of oriental medicine. Also to develop medicinal cuisine according to the perspective of oriental medicinal theory, what should be taken into account is not only the understanding of the characteristics of food materials, but also the properties of them that the theory of oriental medicine. Lastly the scientific effect of the medicinal cuisine which is developed according to the oriental medicinal theory. And it is believed to De essential for the government to make effects to set a standard and laws to validate the medicinal effects and the process of assessment so that the systematic development can be encouraged, and to prepare guidance to food development for national health improvement. This research was planned and executed to evaluate how the composition of Yak-sun(oriental diet therapy) can effect health conditions of people who are suffering from diet-related diseases like cardiovascular related disease. by taking Yak-sun in a form of nutritional supplement with our daily meals. We produced Yak-sun tea with Mansam, Hwanggi, Tanggi and Paekchak and observed nutritional composition. We concluded that we could apply the components not only in a form of tea, but also in other forms of various food. The information we received from this conclusion will be a basic information on how we can apply oriental medicinal resources into other food and will also be a steppingstone for medicinal herbs to step foot in the field of functional food research, which already draws sizable attention world-wide.

• Korean Journal of Crystallography
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• v.6 no.1
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• pp.1-13
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• 1995

Cr:A12O3 and Ti:A12O3 single crystals were grown by Czochralski method, and the effects of crystal growth parameters such as pulling rate, rotation rate, dopant and growth atmosphere on crystal quality were investigated. And spectroscopic properties including lasing efficiency were also measured. Single crystals, sized of 20mm in diameter and 100-135mm in length, were successfully grown from the seed of <001> direction. With the doping level of 0.5w/o Cr2O3, pulling rate 2.0mm/hr, rotation rate of 30rpm and inert atmosphere by nitrogen gas, high quality crystals of Cr:A12O3 were grown. While in case of Ti:A12O3 crystals, high quality crystals were grown under the conditions of the doping level of 0.25w/o TiO2, pulling rate of 1.5mm/hr, rotation rate of 30rpm and reducing atmosphere by hydrogen - nitrogen mixed gas. It was confirmed that Cr3+ ion which maintains its ionoc valence during growth easily de-bubbled than Ti4+ ion which changes its valence, Fe3+ ion also has do-bubbling effect to Ti:A12O3 crystal and the reducing atmosphere by 90% N2 - 10% H2 mixed gas gave effective result on the changing of Ti4+ to Ti3+ and de-bubbling. As a result of spectroscopic measurements of Cr:A12O3 crystal, 4A2 →4F2 and 4F1 absorption transitions and E →4A2(R1) and 2A →4A2(R2) fluorenscence transitions were confirmed. And it was measured that wavelengths of laser R1 and R2 transitions were 696±5nm and 692±5nm respectively, line width of these transitions were 12A, and life-time of fluorenscence was 152μsec. In case of Ti:A12O3 crystals, it was confirmed that absortion transition of 4T2→4E and fluorescence transition of 4E→4T2 with wide range of 650-1050nm was occured. And 147μsec of life-time of fluorescence, 125.4 of figure of merit and 9% of laser efficience were also measured.

• Journal of Animal Science and Technology
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• v.49 no.2
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• pp.161-170
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• 2007

A submerged biofilm sequencing batch reactor (SBSBR) process, which liquor was internally circulated through sandfilter, was designed, and performances in swine wastewater treatment was evaluated under a condition of no external carbon source addition. Denitrification of NOx-N with loading rate in vertical and slope type of sandfilter was 19% and 3.8%, respectively, showing approximately 5 times difference, and so vertical type sandfilter was chosen for the combination with SBSBR. When the process was operated under 15 days HRT, 105L/hr.m3 of internal circulation rate and 54g/m3.d of NH4-N loading rate, treatment efficiencies of STOC, NH4-N and TN (as NH4-N plus NOx-N) was 75%, 97% and 85%, respectively. By conducting internal circulation through sandfilter, removal performances of TN were enhanced by 14%, and the elevation of nitrogen removal was mainly attributed to occurrence of denitrification in sandfilter. Also, approximately 57% of phosphorus was removed with the conduction of internal circulation through sandfilter, meanwhile phosphorus concentration in final effluent rather increased when the internal circulation was not performed. Therefore, It was quite sure that the continuous internal circulation of liquor through sandfilter could contribute to enhancement of biological nutrient removal. Under 60g/m3.d of NH4-N loading rate, the NH4-N level in final effluent was relatively low and constant(below 20mg/L) and over 80% of nitrogen removal was maintained in spite of loading rate increase up to 100g/m3.d. However, the treatment efficiency of nitrogen was deteriorated with further increase of loading rate. Based on this result, an optimum loading rate of nitrogen for the process would be 100g/m3.d.