• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1038-1041
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• 2003

In the paper, we investigated silicon surface microstructures formed by reactive ion etching in hollow cathode system. Wet anisotropic chemical etching technique use to form random pyramidal structure on <100> silicon wafers usually is not effective in texturing of low-cost multicrystalline silicon wafers because of random orientation nature, but High density hollow cathode plasma system illustrates high deposition rate, better film crystal structure, improved etching characteristics. The etched silicon surface is covered by columnar microstructures with diameters form 50 to 100nm and depth of about 500nm. We used $SF_{6}$ and $O_{2}$ gases in HCP dry etch process. This paper demonstrates very high plasma density of $2{\times}10^{12}$ $cm^{-3}$ at a discharge current of 20 mA. Silicon etch rate of 1.3 ${\mu}s/min$. was achieved with $SF_{6}/O_{2}$ plasma conditions of total gas pressure=50 mTorr, gas flow rate=40 sccm, and rf power=200 W. Our experimental results can be used in various display systems such as thin film growth and etching for TFT-LCDs, emitter tip formations for FEDs, and bright plasma discharge for PDP applications. In this paper we directed our study to the silicon etching properties such as high etching rate, large area uniformity, low power with the high density plasma.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.280-284
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• 2004

Multicrystalline silicon wafers were textured in an alkaline bath, basically using sodium hydroxide and in acidic bath, using mainly hydrofluoric acid (HF), nitric acid $(HNO_3)$ and de-ionized water (DIW). Some wafers were also acid polished for the comparative study. Comparison of average reflectance of the samples treated with the new recipe of acidic solution showed average diffuse reflectance less than even 5 percent in the optimized condition. Solar cells were thus fabricated with the samples following the main steps such as phosphorus doping for emitter layer formation, silicon nitride deposition for anti-reflection coating by plasma enhanced chemical vapor deposition (PECVD) and front surface passivation, screen printing metallization, co-firing in rapid thermal processing (RTP) Furnace and laser edge isolation and confirmed >14 % conversion efficiency from the best textured samples. This isotropic texturing approach can be instrumental to achieve high efficiency in mass production using relatively low cost silicon wafers as starting material.

• Molecules and Cells
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• v.38 no.7
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• pp.604-609
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• 2015

The active metabolite of vitamin D such as $1{\alpha}$,25-dihydroxyvitamin ($D_3(1{\alpha},25(OH)_2D_3)$ is a well-known key regulatory factor in bone metabolism. However, little is known about the potential of vitamin D as an odontogenic inducer in human dental pulp cells (HDPCs) in vitro. The purpose of this study was to evaluate the effect of vitamin $D_3$ metabolite, $1{\alpha},25(OH)_2D_3$, on odontoblastic differentiation in HDPCs. HDPCs extracted from maxillary supernumerary incisors and third molars were directly cultured with $1{\alpha},25(OH)_2D_3$ in the absence of differentiation-inducing factors. Treatment of HDPCs with $1{\alpha},25(OH)_2D_3$ at a concentration of 10 nM or 100 nM significantly upregulated the expression of dentin sialophosphoprotein (DSPP) and dentin matrix protein1 (DMP1), the odontogenesis-related genes. Also, $1{\alpha},25(OH)_2D_3$ enhanced the alkaline phosphatase (ALP) activity and mineralization in HDPCs. In addition, $1{\alpha},25(OH)_2D_3$ induced activation of extracellular signal-regulated kinases (ERKs), whereas the ERK inhibitor U0126 ameliorated the upregulation of DSPP and DMP1 and reduced the mineralization enhanced by $1{\alpha},25(OH)_2D_3$. These results demonstrated that $1{\alpha},25(OH)_2D_3$ promoted odontoblastic differentiation of HDPCs via modulating ERK activation.

• Journal of architectural history
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• v.8 no.4 s.21
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• pp.39-62
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• 1999

Basic concept of this study is that architectural form as a material at present has meaning for the dweller's life on the past historical plane. Main method to recover history is ethnographic interview to dwellers. Secondary method is to analyze ancestors' writings, buildings in the background of the family photos, and past drawings and then to relate them with architectural form at present. Taxonomy is a starting point: general name of the building by outside researcher is quite different from it by inside dwellers. 'Haengrang-chae', servant quarter, has never been used for servants. Function of the haengrang went outside thatched houses at the front village. Firsthand observation or simple analyses as results of several precedent research are reexamined and criticized through this study. The mansion has moaning when we synthesize with the site location based on farming land and tenant farmer, and decline of the Kyongpo Lake. Territoriality of the mansion is reinterpreted to 'In-Out Structure' by Yin-Yang thinking, Dwellers extend buildings gradually to outside village, surrounding rear hills, the lake, DongHae Sea, and finally goes to imaginative Taoist heaven beyond real nature through the literary life. Confucius principle, known to govern upper class house at Yi Dynasty also affect general composition of the buildings: perpetuation of the family by ancestor worship, elder dominance and male dominance, fraternity love in the extended family, charity display by reception of guests, Taoist scholarly life harmonized with nature. However, the study of the particular life and usage of the dwellers reinforces or corrects general supposition of precedent researches. Unique shape of the house has been formed by convenience of the dwellers' life style, early modernized free thought over the rigid Confucius design principle, and female power in male dominant society.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.143-155
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• 2014

The purpose of this study was to analyze adaptation for Korean foods and satisfaction for university foodservice by nationality and residence period of Chinese and Japanese university students in Daejeon, Republic of Korea. Among 330 questionnaires distributed to Chinese and Japanese students, 294 complete questionnaires (89.1%) were analyzed. The questionnaire included two 5-point scales for measuring levels adaptation of for Korean food and satisfaction with university foodservice, respectively. Japanese students' level of adaptation for Korean food (3.16) was significantly higher than that of Chinese students (2.96). As the length of residence in Korea increased, the frequency of using university lunch service per week significantly decreased. The main factor when selecting a menu item was food taste (39.8%, 22.8%) in both Chinese and Japanese students, whereas the next main factor was preference (16.4%) in Chinese students and nutrition (18.7%) in Japanese students. The preferred cooking methods for meat were stir-frying (31.6%) and roasting (25.9%). For fish, Chinese students preferred braising (32.7%), whereas Japanese students preferred roasting (26.8%). Both Chinese and Japanese students preferred sukchae (45.6%, 43.1%) for vegetables. Factor analysis grouped 17 items measuring university foodservice into four factors, 'sanitation & employee service', 'physical environment', 'food' and 'customized menu & information' and the mean scores were 3.56, 3.30, 3.20 and 3.00, respectively. Chinese students were significantly more satisfied than Japanese students with the 'physical environment', 'sanitation & employee service' and 'customized menu & information'. These results suggest that efforts such as developing a greater variety of menu items with mild tastes and somewhat less flavor, applying preferred cooking methods, offering special menus for foreign students, providing nutrition information on menus, and offering a description of menu items in the foreign languages could improve Chinese and Japanese students' levels of satisfaction with university foodservice.

• Korean journal of food and cookery science
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• v.23 no.3 s.99
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• pp.321-326
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• 2007

The microbial contamination levels of school classrooms were assessed as foodservice environments for elementary students. Two elementary schools located in Kyunggi-do were selected, and the total plate counts (TPC) and coliforms were measured from the classroom facilities, including the tables, chairs, floors, shelves, doors, as well as the hands of students, and the air of classrooms. The TPC of the classroom facilities were relatively low ranging from 2.30 to 3.79 log CFU/100 cm$^2$. The TPC counts from the hands of serving students and served students, were 6.39 and 5.33 log CFU, respectively, and the TPC counts of the foodservice utensils were <3.00 log CFU/ea before use and 4.77 CFU/ea after use. The air samples of 'empty classrooms during physical education', 'after physical education class', and 'during lunch' showed the contamination levels of 26 CFU/m$^3$,392 CFU/m$^3$, 364 CFU/m$^3$, respectively, suggesting that the microbial levels in the air varies greatly depending on the class activity before foodservice. When the TPCs of the air during lunch were measured from 18 classrooms, the levels ranged from 76 to >2228 CFU/m$^3$. Coliforms were not detected in the classroom facilities; however, air samples of the classrooms showed 1${\sim}$2 CFU/m$^3$. The above results show that classroom air and the hands of students, can have high levels of microbial contamination, which must to be controlled for safer school foodservice.

• Journal of the Korean Society of Safety
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• v.30 no.6
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• pp.40-47
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• 2015

In this study, temperature characteristics and fire damage form were analyzed to investigate flame spreading form and fire probability from ignition sources subject to drivit component materials which is finishing material in architecture. Ignition sources were limited to a gas torch and exterior panel board fire, and the size of the sample was manufacture in 30 cm length ${\times}$ 50 cm height ${\times}$ 5cm thickness size. Marble (inner wall) + 3 mm drivit (outer wall), marble (inner wall) + 4 mm plaster stone (outer wall), sandwich panel + 3 mm driver bit (outer wall), sandwich panel + 3 mm driver bit + insulation (outer wall), and gypsum board (inner wall) + 3 mm drivit (outer wall) were prepared for the sample. As result of the research for temperature characteristics, large temperature difference by each material was shown in $218^{\circ}C{\sim}995^{\circ}C$ at 30 seconds and $501^{\circ}C{\sim}1078^{\circ}C$ at 300 seconds. Especially when the inner wall was a plaster board, lowest temperature of $501^{\circ}C$ was shown at 300 seconds and marble inner wall showed the following lowest temperature of $900^{\circ}C$. Temperature rising over $1000^{\circ}C$ was shown in other materials. Regarding fire damage form, drivit or gypsum board outer wall parts exposed to fire showed combustion and carbonization to show calcination(breaking phenomenon) and influence of heat exposure was higher as calcination became more severe.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.12
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• pp.1791-1797
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• 2007

A study was conducted with 70 Hanwoo (Korean cattle) for genotyping bovine leukocyte antigen (BoLA)-DRB3.2 gene by using the polymerase chain reaction (PCR) and sequence based typing (SBT). Two-step PCR was carried out for amplifying a 284 bp fragment of the target gene and the PCR products were digested with three restriction enzymes namely RsaI, BstYI and HaeIII. Seventeen alleles were detected with frequencies ranging from 1.43 to 18.57% and one (x'aa) of these alleles was identified as a new allele that has not been reported before. The frequency of the new x'aa allele identified in this breed was 12.86%. In addition, the seven most frequently observed alleles (DRB3.2 *10, *15, *16, *26, *27, *54 and x'aa) accounted for 74.28% of the alleles in this population. The phylogenetic tree showed that the BoLA-DRB3.2 allele sequences of Hanwoo were shared with other Bos taurus breeds and no specific clade for Hanwoo was identified. It indicates high heterogeneity of the BoLA-DRB3 gene in this population and may give some ideas for breeding animals having better disease resistance.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.3
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• pp.125-132
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• 2013

Objectives The purpose of this study was to compare the effects of acupuncture treatment with those of collaborative treatment regarding acute Bell's palsy. Methods Twenty-six patients who received outpatient treatment between March 2012 and February 2013 were divided into 2 groups. The East-West treatment group (EW group, n=12) received prednisolone and then acupuncture afterwards. The Eastern treatment group (E group, n=14) received just acupuncture. Acupuncture was administered 3 to 4 times a week, and both groups were educated to practice facial muscle exercises at home. Evaluations were made before treatment, after 1 week, 2 weeks, and 3 weeks using the House-Brackmann facial nerve grading system. Results Compared to before treatment, the House-Brackmann grades of both EW and E groups after 1, 2 and 3 weeks of treatment significantly decreased (p<0.05). Regarding group comparison, the House-Brackmann grade of the EW group was significantly lower than the E group at 1 week (p=0.043), but there was no significant difference at 2 and 3 weeks. Regarding improvement of House-Brackmann grades, there was no significant difference between the two groups at 1, 2 and 3 weeks (p>0.05). Conclusions Compared to just acupuncture treatment, collaborative treatment with prednisolone significantly improved the House-Brackmann grade after 1 week, but there was no difference as time passed. Because early intervention determines the prognosis of Bell's palsy, collaborative treatment at the early stage will be clinically helpful to patients.

• Journal of the Korean Society of Costume
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• v.61 no.4
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• pp.52-62
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• 2011

This study is about the history of costumes depicted on the book Goryosa(高麗史) Ye-Ji(禮志). Researches about the costumes of Goryo dynasty are very rare and are mostly based on Goryodogyung(高麗圖經) and Goryosa Yebok-Ji(與服志). However, records about suitable costumes for a special scene of a rite can also be found in Ye-Ji besides Yebok-Ji. Therefore, this study analyzes Ye-Ji and categorizes the results into character and situation. Characters that can be found are king, officials, crown prince, aristocrat, commoner and envoy. Situations that can be found, according to the original text, are Gilrye(吉禮), Hyoongrye(凶禮), Goonrye(軍禮) and Garye(嘉禮). The results of the study are as follows; $\blacktriangleright$ The king had to change clothes in order to suit the situation according to the precise sequence of rituals. Therefore the king had to wear different clothes in the same rite, optionally, depending on the situation. This also applies to the case of officials. $\blacktriangleright$ The crown prince and aristocrats generally wore the same clothes as officials. $\blacktriangleright$ In the important ritual of Garye(嘉禮), many cases can be found where officials wore Jobok(朝服) and hands-on worker wore Gongbok(公服). $\blacktriangleright$ It is remarkable that on the New Year's day, the winter solstice and Sungsoojul(聖壽節; the emperor's birthday) the envoy of Ming Sangbok(常服); whereas the king and the officials of Goryo wore the Myunbok(冕服) or Jobok(朝服).