• Journal of Conservation Science
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• v.32 no.2
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• pp.123-139
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• 2016

The excavated potteries of Goryeo Period from the Sandongri archaeological site in Seosan were studied on physicochemical analyses. Surface color of the samples are mainly grayish blue, and showed the natural glaze by melting the body soils during the burning. Partly, swelling surface are observed bloated marks because of blow out gas by burning. The potteries are some possibility of making the similar source clay on the basis of magnetic susceptibilities (about $1{\times}10^{-3}SI\;unit$) and general occurrences. Values of specific gravity, apparent porosity and absorption ratio are divided two groups as highly different cases of bloating surface samples. The source clay of the potteries used mainly microcrystalline clay, the mineral compositions are quartz and some colored minerals. Based on the analysis, the burning temperature of the potteries are assumed that they were around $1,100^{\circ}C$ because detection of quartz and mullite within hard and compact matrices. As geochemical variations of the samples, evolution trends of rare earth, compatible and incompatible elements showed very similar patterns excepting the some major elements, that means the potteries are interpreted to making by elutriation processes using the same raw clays from very similar basement rocks of genetically.

• Polymer(Korea)
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• v.24 no.2
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• pp.268-275
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• 2000

We investigated the effect of polymer sublayer on volumetric resistivity and tensile strength of carbon fiber (CF)/polyethylene composite films fabricated under high intensity electric fields. The dependence of volumetric resistivity and tensile strength of the films on the polymer sublayer thickness or mass part exhibited complex behavior according to CF content and CF layer density in the films. As the thickness of polymer sublayer increases, two groups of processes at thermo-mechanical forming stage would take effects in the properties of the films. The first group comprises the increase of polymer layer thickness having reduced CF content compared with central or upper part of the film and insufficient wetting of CF resulting in the loosened structure near upper film side. The second group, on the other hand, is the improvement of mobility of molten sublayer leading to better distribution of CF throughout the film thickness and the formation of more compact structure. The different degree of contribution of these two competing processes at varied CF content and CF layer density could explain complex dependence of the film properties on the polymer sublayer. These results are important to optimize the electrical and mechanical properties of highly conductive polymer films, which can be used as electromagnetic interference shielding materials.

• Food Science and Preservation
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• v.19 no.1
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• pp.19-25
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• 2012

An experiment was conducted to find out the effect of brushing treatment during cultivation on the postharvest quality of the baby leaf vegetable, specifically tah tasai Chinese cabbage (Brassica campestris var. narinosa). The effect of mechanical brushing during cultivation on the postharvest quality was determined in terms of the quality changes in weight loss, gas partial pressure, leaf color, and appearance during storage using a 30-${\mu}m$-thick polypropylene film at $16^{\circ}C$. The brushing treatment included brushing with A4 paper back and forth 50 times a day. The study revealed that the growths on the brushing-treated plant group were less than those on the control group. The structure of the leaf tissue of the brushing-treated plant also tended to be less compact than that of the non-treated plant. The brushing treatment resulted in less growth and denser plant tissues as well as in differences in the gas $O_2$ consumption and $CO_2$ accumulation after packaging. For the gas partial pressure, the $O_2$ consumption and $CO_2$ accumulation of the brushing-treated plant tended to be less than those of the non-treated plant. There were no differences, however, between the brushing-treated plant and control groups in the SPAD value and appearance. The study results also suggested that after packaging, the effects of the brushing treatment during cultivation on the quality of the tah tasai Chinese cabbage baby leaf vegetable was not significant. As such, it is recommended that effective post-harvest methods of improving the product quality of the baby leaf vegetable be further investigated.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.1
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• pp.48-58
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• 2001

After performing mandibular setback surgery, we found some changes in patterns and organs of speech. This investigation was undertaken to investigate the aspect and degree of speech patterns according to the amount of surgical setback in mandibular prognathic patients. Thirteen patients with skeletal Class III malocclusion were studied preoperative and postoperative over 6 months. They had undergone the mandible setback operation via bilateral sagittal split ramus osteotomy(BSSRO). We split the patients into two groups. Group 1 included patients whose degree of mandibular setback was 6mm or less, and Group 2 above 6mm. Control group was two adults wish normal speech patterns. A phonetician performed narrow phonetic transcriptions of tape-recorded words and sentences produced by each of the patients and the acoustic characteristics of the plosives, fricatives, and flaps were analyzed with a phonetic computer program (Computerized Speech Lab(CSL) Model 4300B(USA)). The results are as follows: 1. Generally, Patients showed longer closure duration of plosives, shorter VOT(voice onset time) and higher ratio of closure duration against VOT. 2. Patients showed more frequent diffuse distribution than the control group in frication noise energy of fricatives. 3. In fricatives, frequency of compact from were higher in group 1 than in group 2. 4. Generally, a short duration of closure for /ㄹ/ was not realized in the patient's flaps. Instead, it was realized as fricatives, sonorant with a vowel-like formant structure, or trill type consonant. 5. Abnormality of the patient's articulation was reduced, but adaptation of their articulation after surgery was not perfect and the degree of adaptation was different according to the degree of surgical setback.

• Applied Microscopy
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• v.31 no.2
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• pp.109-116
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• 2001

Safflower has been cultivated in Korea and thought to have excellent effects on bone in oriental medicine and folk remedy and has been taken for a long time. Safflower is thought to be helpful for the development and sustenance of bones according to the result of recent assay of its components. Otherwise, any reliable experimental data have not been suggested so far. We have carried out this study to examine the prophylactic effects of safflower-seed-powder on the prevention of osteoporosis induced by the ovariectomy 12 Weeks-old Sprague-Dawley rats weighing about 230 g was kept in the experimental condition and used in this study. Animals were taken 0.3 g of safflower-seed-powder once a day for 1, 3, 5, and 7 weeks after ovariectomizing both ovaries and observed the fine structure of tibia. Tissues were fixed with traditional SEM preparation methods and decalcified for 10 hours with 10% nitric acid and dehydration, drying, and gold-coating were followed by the routine procedures and observed with scanning electron microscope (Hitachi, S-450). Loss of bone was started just after ovariectomy and thickness of bone from the medullary cavity to the compact bone was reduced and the extension of medullary cavity was serious in the control group of 7 weeks. Experimental groups taken safflower-seed-powder showed similar findings from 1 week to 7 weeks. These results suggest that the safflower-seed-powder is thought to be efficient for the prevention of osteoporosis owing to the deficiency of female sex hormone.

• Journal of Conservation Science
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• v.25 no.3
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• pp.255-271
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• 2009

This study was examined interpretation of making techniques and provenance interpretation of raw materials for the potteries from the Nongseori site in Giheung based on archaeometric characteristics. The potteries are classified into three groups according to the archaeological age. The texture of Neolithic age potteries is sandy soil added a lot of temper such as talc and mica, and Bronze age potteries contain sandy materials which occur naturally include quartz, orthoclase, plagioclase and mica. On the other hand, Proto-three Kingdom Age potteries made of silty soil that sift out coarse minerals from the clay. But all pottery and soil samples in the study were very similar patterns with geochemical evolution trend. This result is sufficient evidence that all pottery samples were produced using the same raw materials from the host rocks around of the site area. The Neolithic age potteries had loose texture and fired probably about 700 to $760^{\circ}C$. The Bronze age potteries had experienced firing about 850 to $900^{\circ}C$. And Proto-three Kingdom Age potteries had compact textured and fired from 900 to $1,050^{\circ}C$. The making techniques of potteries are not represented discontinuation characteristics about the periodic time sequences, and are suggested that revealed a transitional change patterns for production techniques.

• Science of Emotion and Sensibility
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• v.22 no.4
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• pp.3-14
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• 2019

The café has become an important representative "third place" where people study and rest. Hence, it is worthwhile for researchers to understand the needs of individual users as well as the requirements of people who visit such venues in groups. The identification of strategies that can help achieve larger, wider, higher, or deeper interior spaces in small and compact locations can generate benefits for both users and designers. In this study, where 56 interior design students participated, we used an eye-tracker and images of cafes to explore the relationships between spatial depth and the intention to visit a cafe space. The researchers digitally developed fifteen different conditions of space and measured the eye movements of the participants using an eye-tracker when they examined images that appeared to convey the most depth. Participants were also asked to imagine the proposed space images as cafes and to select one of the 15 images as the location that they would be most likely to visit individually and one that they would frequent in the company of other people. The research results revealed that certain ways of using interior design elements altered the participants' perceptions of spatial depth without any change being effected to the actual volume or the size of the space. The participants tended to perceive a space with a small decorative artwork on a dark toned wall with unconnected furniture as deeper than a space with no or large artwork on a light toned wall with contiguous furniture. Spatial depth was a more important consideration for an individual visit than for a group visit. The results of this exploratory study will help scholarly understanding of the role played by spatial depth in customer intentions to visit a cafe.

• Journal of Periodontal and Implant Science
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• v.38 no.sup2
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• pp.363-372
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• 2008

Purpose: This study compared the effects of coating implants with hydroxyapatite (HA) using an ion beam-assisted deposition (IBAD) method prepared with machined, anodized, sandblasted and large-grit acid etched (SLA) surfaces in minipigs, and verified the excellency of coating method with HA using IBAD. Material and Methods: 4 male Minipigs(Prestige World Genetics, Korea), 18 to 24 months old and weighing approximately 35 to 40 kg, were chosen. All premolars and first molars of the maxilla were carefully extracted on each side. The implants were placed on the right side after an 8 week healing period. The implant stability was assessed by resonance frequency analysis (RFA) at the time of placement. 40 implants were divided into 5 groups; machined, anodized, anodized plus IBAD, SLA, and SLA plus IBAD surface implants. 4 weeks after implantation on the right side, the same surface implants were placed on the left side. After 4 weeks of healing, the minipigs were sacrificed and the implants were analyzed by RFA, histology and histometric. Results: RFA showed a mean implant stability quotient (ISQ) of $75.625{\pm}5.021$, $76.125{\pm}3.739$ ISQ and $77.941{\pm}2.947$ at placement, after 4 weeks healing and after 8 weeks, respectively. Histological analysis of the implants demonstrated newly formed, compact, mature cortical bone with a nearby marrow spaces. HA coating was not separated from the HA coated implant surfaces using IBAD. In particular, the SLA implants coated with HA using IBAD showed better contact osteogenesis. Statistical and histometric analysis showed no significant differences in the bone to implant contact and bone density among 5 tested surfaces. Conclusion: We can conclude that rough surface implants coated with HA by IBAD are more biocompatible, and clinical, histological, and histometric analysis showed no differences when compared with the other established implant surfaces in normal bone.

• Journal of Periodontal and Implant Science
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• v.37 no.2
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• pp.209-221
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• 2007

Recently, immediately after losing teeth. implant placement has been greatly attempted. Implant can help restoration of tooth functions within short time. This study was an attempt to examine the extent of osseointergation when the implants will be placed immediately after teeth extraction using domestic implant systems. Implants were inserted in beagle dogs and evaluated the clinical, radiological, histological and histomorphometric assay at 6 weeks and 12 weeks. For experimental materals, $STAGE-1^{(R)}$($4.1{\times}8mm$, Lifecore, USA), $SS-III^{(R)}$($4.0{\times}8mm$, OSSTEM, Korea) and $IFI^{(R)}$($4.0{\times}8mm$, Dio, Korea) implants treated with RBM were placed. All the placed site showed normal results without fail and inflammation clinically and radiologically. As a result of measurement by periotest, it showed $-2\;{\sim}\;-5$ and stable status comprehensively. There was no statistically significant difference among implants(p<0.05). Bone tissue adjacent to implant showed increased marrow tissue at 6 weeks. Nevertheless, osteogenic structure was not observed remarkably. In a 12 weeks opinion, bone tissue composed of osseointegration along implant interface showed significantly decreased marrow tissue containing central vessels unlike a 6 weeks opinion and matured compact bone whose osteogenic structure is well formed. BIC were 42.4%, 32.0% and 34.9%, respectively in 6 weeks and there was no statistically significant difference among group(p<0.05). In 12 weeks, BIC were 58.8%, 61.9% and 57.5%. respectively and there was no statistically significant difference among groups(p<0.05). It is considered that all 3 implant systems are suitable for immediate implant placement.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.4
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• pp.403-413
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• 2017

The study was conducted to understand the meaning of the voluntary service experience of Korean-Chinese who living in South Korea and examine the reason of participating in voluntary activities. 8 people participated in the study, who come from volunteering groups in a Korean-Chinese compact community. Data were collected through in - depth interviews and participation observation. The collected data were categorized and analyzed according to Giorgi's hermeneutic phenomenological research method. As a result of the analysis, three sets of themes were drawn on the nature of their volunteering experience. Through their volunteer activities, they have been improving their images that have been damaged and stigmatized by the mainstream society. Through their volunteer activities, they have improved their self-esteem, got more information about the society and better adapted to Korean society. Moreover, through their volunteer activities, they have increased their sense of responsibility for Korean society and redefined their position in Korea. Given this, they expect the possibility of becoming a global citizen for the future. The meanings of volunteer experience of Chinese Koreans have been examined and discussed in this study, which indicated that the activation of the volunteer activities of migrants contributes positively to the integration of multicultural society.