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A Study on the Micro Discourse about Urban Parks in Blogs - In the Case of the Seoul Forest - (블로그(Blog)에 나타난 도시공원 미시담론 - 서울숲을 대상으로 -)

  • Lee, Jaei;Sung, Jong-Sang
    • Journal of the Korean Institute of Landscape Architecture
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    • v.43 no.1
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    • pp.29-39
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    • 2015
  • This study has attempted to determine the micro-discourse from blogs as personal media that reflect citizens' actual opinions of the Seoul Forest without intervention of experts. Furthermore, a qualitative research method discourse analysis was selected to analyze the micro-discourse regarding the Seoul Forest in a time series. The extracted samples of blogs by year were intended to identify the comment section of the process of change and the discursive structure. The results are as follows; first, from the beginning of the development of the Seoul Forest to the present, it is divided into four chronological periods along with individuals' micro-discourse with social changes. During the beginning of the development of the Seoul Forest, the social discourse was formed, and in the next period, the micro-discourse was developed with a more emotional and complex discourse. In the formative period, four or five years later, the discourse reflected the civic consciousness of development more than ever, showing the diversity of participation in the program at the Seoul Forest. In the growth period, as the users' experiences had been accumulated, the users started writing about the role of the Seoul Forest in their own words. This can also be called place discourse. From the individuals' micro-discourse, this study shows the discourse structure of how individuals think about the Seoul Forest in each period. Unlike the experts, the micro-discourse contains specific daily interactions, experiences, and the stories of individuals who actually use the parks. It also shows how users reproduce and understand the space. In this respect, this is the most significant finding of this study. Based on this research, this study has demonstrated that the emotional description of a place that actually functions as a discourse about city parks, and confirms that blogs could be used as a space to form discourse and as a research tool to read the trends. In accordance with these results, this study has described not only the discourse of experts, but also how the discourse of individuals' comments can be an important part of the discourse of modern urban parks.

Phosphorous Removal in a Free Water Surface Wetland Constructed on the Gwangju Stream Floodplain (광주천 고수부지에 조성한 자유수면인공습지의 인 제거)

  • Yang, Hong-Mo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.1
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    • pp.100-109
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    • 2012
  • Removal rates of $PO_4-P$ and TP in a free water surface wetland system were investigated. The system was established in 2008 on a floodplain in the middle reach of the Gwangju Stream flowing through Gwangju City. Its dimensions were 46 meters in length and 5 meters in width. Two year old Typha angustifloria L. growing in pots were planted on half of the area and Zizania latifolia Turcz on the other half in 2008. Stream water was funneled into the wetlands by gravity flow, and its effluent was discharged back into the stream. The influent volume was controlled by valves and water depth was adjusted by wires. Volume and water quality of inflow and outflow were analyzed from January to December in 2010. Inflow into the system averaged approximately $710m^3/day$ and hydraulic residence time was about 1.5 hours. Average influent and effluent $PO_4-P$ concentration were 0.144 and 0.103mg/L, respectively, and $PO_4-P$ abatement amounted to 28.6%. Influent and effluent TP concentration averaged 0.333 and 0.262mg/L, respectively, and TP retention reached to 20.7%.$PO_4-P$ removal rate(%) during plant growing season(31.448) was significantly high(p<0.001) when compared with that during plant non-growing season(25.829). TP abatement rate(%) during plant growing season(27.230) was also significantly high(p<0.001) when compared with that of the non-growing season(14.856). Major phosphorous removals in the system resulted from adsorption of phosphorous in the litter-soil layers; sedimentation of particulate phosphorous and Ca, Al, Fe bounded phosphates; and absorption of phosphorous by emergent plants. The adsorption and sedimentation occurred throughout the year, however, the absorption took place during plant growing season. This resulted in higher removals of $PO_4-P$ and TP during plant growing season.

A Study on Comparison of Changes in Ecological Characteristics for Bulgwangcheon(stream) Close-to Nature Section (불광천 자연형 하천 정비구간의 생태적 특성 변화 비교 연구)

  • Park, Won-Zei;Lee, Kyong-Jae;Han, Bong-Ho;Jang, Jae-Hoon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.2
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    • pp.112-129
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    • 2012
  • The aim of this study was to provide basic data in managing the project that was carried out on Bulgwangcheon in a nature-friendly way to improve the conditions around the areas, which was brought to completion in 2002, based on changes in ecological characteristics. For this propose, this study examined documents related to the project, compared physical and enviromnental changes before and after the project was conducted and analyzed changes in the stream ecosystem. The result showed that in areas that effluent water was often observed, especially when it rained, the river wall was washed away and vegetation was found damaged. As for actual vegetation, this study compared planting coverage of each section of the research area and actual vegetation charts. The results indicated that Lespedeza spp., Aster koraiensis among mixed seeds that were planted in the reservoir path were almost swept away while Festuca arundinacea dominated the areas. Phragmites communis, Miscanthus sacchariflorns and Salix gracilistyla which had been planted in a small number were also almost washed out though a small number of them were left to form a colony. After examining the topography and structure of the plant community, this study found that areas where mixed seed were planted had changed into two types of vegetation: First type of area is dominated by P and R which are usually raised in apron with abundant floating particles. The second type of area is dominated by dry gramineous plant such as F and A. Areas around low flow channel where Phragmites communis, Miscanthus sacchariflorus and Salix gracilistyla planting construction method is applied was washed away with the width of low flow channel reduced. Though P, M and S formed a small community in some areas around the low flow area, they were in small number and in composition of simple plant species. Two ways were suggested in this study to manage the stream in an ecological way. First, adequate revetment construction methods should be applied by monitoring the flow of the stream as well as considering the flood control of urban streams. Second, target vegetation communities that are suitable for the environment of the stream should be chosen and be plantedconstantly with high density. At the same time, ornamental native plants shouldn't be planted as they have been and disturbing vegetation should be removed.

A Study on A Phase of Denotation Expansion of Oriental Medicine in the late Joseon Dynasty (조선(朝鮮) 후기(後期) 한의학(韓醫學) 외연확대(外延擴大)의 일국면(一局面))

  • Park, Sang-Young;Oh, Jun-Ho;Kwon, Oh-Min
    • Korean Journal of Oriental Medicine
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    • v.17 no.3
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    • pp.1-8
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    • 2011
  • In the late Joseon Dynasty, a bulky volume of books, which had rarely been seen, poured out including "Imwongyeongjeji", "Japdongsani", "Songnamjapsik" and "Ohjuyeonmunjaangjeonsango". such sorts of books have a characteristic that an author collected various pieces of information, which were scatter away at that time, in one's own way and compiled them into a book rather than an author's own remarks or ideas. Most authors of such books were known to have made not a few book beside bulky books. Such a trend of the times doubled its revitalization with the influx of that books in a series that were popular especially in the period of Ming State & Ching State in China. The research work on such a trend once showed not a little progress by a few faithful researchers even under the circumstances where they were overwhelmed by the bulkiness of a book in a series itself and its target volume. However, in spite of not a little fruition of such studies, there has been no comments at all on the new factors of change faced by Oriental medicine in the climate of the intellect history in the late Joseon Dynasty. Thus, this study aimed at looking at the significance of medical-history-based studies on this matter on the basis of Park, Jiwon's "Keumryosocho", and Lee, Deokmu's "Iemokgushimseo", and suggesting the further task. The conclusions obtained from the analysis of "Keumryosocho" and "Iemokgusimseo" are as follows: 1.The prescriptions cited from the sorts of writings excluded entirely the medical theories on the principles of prescription, and they are composed of a single-medicine prescription or so, which made it easier even for those who lacked a special knowledge of medicine to use it; in addition, it was easy to get medicinal ingredients in most cases. It's presumed that such a composition of medicinal ingredients had a close relation with the difficulty in the supply of medicinal ingredients, which issue became a serious issue in the late Joseon Dynasty. 2. The prescriptions originating from the sorts of writings sometimes are mixed with the ones whose medical efficiency are doubted. This means the inherence of obstacles to delivering accurate medical knowledge couldn't be avoided because the initial purpose of such sorts of writings lay in popularity than practicality. 3. In spite of such problems, the prescriptions originating from writings seems to have not a few influences on the intellectuals in the late Joseon Dynasty, and it's possible for us to take a glance on the traces of their use of these prescriptions in an actual daily life. This fact is fully confirmed by the contents in the preface of "Keumryosocho" that Park-jiwon personally tried to write a prescription. Moreover, such facts can be also confirmed from the fact that the writings of China or our country are seen quite often among the writings which were incited by Seo, Yugu's "Injeji." Like this, the fact that the information of orthodox medicine and the one originating from general books other than medicine books were integrated at one place is plainly showing a phase of the intellect history in the late Joseon Dynasty deluged with information; because of such a characteristic, we can say that Oriental medicine became plentiful in the aspect of diversity with its expansion of denotation, but Oriental medicine could not but additionally assume the problem of having to distinguish good from bad in the midst of such a situation.

The evaluation of clinical efficacy and longevity of home bleaching without combined application of In-office bleaching (자가미백술 단독사용시 임상적 효능 및 유지력 평가)

  • Shin, Byunk-Gyu;Yang, Sung-Eun
    • Restorative Dentistry and Endodontics
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    • v.35 no.5
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    • pp.387-394
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    • 2010
  • Objectives: The purpose of this study was to evaluate the whitening efficacy and longevity of home bleaching. Materials and Methods: A total of 28 patients were divided into either experimental group (Opalescence F; 15% carbamide peroxide) or control group randomly. The patients in experimental group were instructed to wear individual trays applied with bleaching gel for 2 hours a day for 4 weeks. Any treatments weren't applied to the patients in control group. The color measurements of central incisors, lateral incisors & canines of upper and lower arch were recorded at base line, immediately after the finishment of treatmemt (4 weeks), 8 weeks and 12 weeks using Colorimeter (Chroma Meter, 2600d Konica Minolta co.) and Vitapan classical shade guide (Vita Zahnfabrik). Results: A significantly stronger color change was observed for overall teeth samples in experimental group immediately after treatment (at 4 weeks) compared to ones in control group (p < 0.05). There was also a significant difference between baseline and 8 weeks or 12 weeks separately though color rebouncing phenomenon occurred as time went by (p < 0.05). Conclusions: The clinical effecacy and longevity of home bleaching without combined application of in-office bleaching was observed through this experiment.

Effects of the color components of light-cured composite resin before and after polymerization on degree of conversion and flexural strength (광중합형 복합레진의 중합 전, 후의 색 성분이 중합률과 굴곡강도에 미치는 영향)

  • Yoo, Ji-A;Cho, Byeong-Hoon
    • Restorative Dentistry and Endodontics
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    • v.36 no.4
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    • pp.324-335
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    • 2011
  • Objectives: This study investigated the effects of the color components of light-cured composite resin before and after polymerization on degree of conversion (DC) and biaxial flexural strength (FS). Materials and Methods: Four enamel shades (A1, A2, A3, A4) and two dentin shades (A2O, A3O) of Premisa (Kerr Co.) and Denfil (Vericom Co.) were evaluated on their CIE $L^*,\;a^*,\;b^*$ color components using the spectrophotometer before curing, after curing and at 7 day. The DC of same specimens were measured with Near-infrared spectrometer (Nexus, Thermo Nicolet Co.) at 2 hr after cure and at 7 day. Finally, the FS was obtained after all the other measurements were completed at 7 day. The correlations between each color component and DC and FS were evaluated. Results: The light-curing of composite resin resulted in color changes of Premisa in red-blue direction and Denfil in green-blue direction. The DC and FS were affected by product, time and shade (3-way ANOVA, p < 0.05) and product and shade (2-way ANOVA, p < 0.05), respectively. Premisa only showed a significant correlation between the DC and CIE $a^*$ component - before and after polymerization (Pearson product moment correlation, p < 0.05). The FS of Premisa showed significant negative correlations with CIE $a^*$ and CIE $b^*$ components. Conclusions: The DC and FS of the light-curing composite resin were affected by the color components of the material before and after polymerization.

Clinical assessment of whitening efficacy and safety of in-office tooth whitening system containing 15% hydrogen peroxide with or without light activation (15% 과산화수소 함유 전문가용 치아 미백제의 광활성화 여부에 따른 미백효과 및 안전성에 관한 임상평가)

  • Noh, Young-Suk;Rho, Young-Jee;Yoo, Yeon-Jee;Lee, Hyang-Ok;Lim, Sang-Min;Kweon, Hyun-Jeong;Kim, Ye-Un;Park, Seong-Yeon;Yoon, Hee-Young;Lee, Jung-Hyun;Lee, Chan-Hee;Oh, So-Ram;Kum, Kee-Yeon
    • Restorative Dentistry and Endodontics
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    • v.36 no.4
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    • pp.306-312
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    • 2011
  • Objectives: This clinical study evaluated the effect of light activation on the whitening efficacy and safety of in-office bleaching system containing 15% hydrogen peroxide gel. Materials and Methods: Thirty-three volunteers were randomly treated with (n = 17, experimental group) or without light activation (n = 16, control group), using Zoom2 white gel (15% $H_2O_2$, Discus Dental) for a total treatment time of 45 min. Visual and instrumental color measurements were obtained using Vitapan Classical shade guide and Shadepilot (DeguDent) at screening test, after bleaching, and 1 month and 3 month after bleaching. Data were analyzed using t-test, repeated measure ANOVA, and chi-squared test. Results: Zoom2 white gel produced significant shade changes in both experimental and control group when pre-treatment shade was compared with that after bleaching. However, shade difference between two groups was not statistically significant (p > 0.05). Tooth shade relapse was not detected at 3 months after bleaching. The incidence of transient tooth sensitivity was 39.4%, with being no differences between two groups. Conclusions: The application of light activation with Zoom2 white gel system neither achieved additional whitening effects nor showed more detrimental influences.

EVALUATION ON THE ABRASION RESISTANCE OF A SURFACE SEALANT (레진전색제의 마모저항성에 대한 평가)

  • Kim, Soo-Mee;Han, Sae-Hee;Cho, Young-Gon
    • Restorative Dentistry and Endodontics
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    • v.32 no.3
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    • pp.180-190
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    • 2007
  • The purpose of this study was to evaluate the abrasion resistance of surface penetrating sealant which was applied on a composite resin restoration and to provide proper time to reapply sealant on composite resin surface. Two hundred rectangular specimens, sized $8\times3\times2mm$, were made of Micronew (Bisco, Inc., Schaumburg, IL, U.S.A) and divided into two groups; F group (n = 10) was finished with coarse and medium grit of Sof-Lex discs and BisCoverwas applied B group (n = 190) after finishing with discs. B group was again subdivided into nineteen subgroups From B-1 group to B-18 group were subjected to toothbrush abrasion test using a distilled water-dentifrice slurry and toothbrush heads B-IM group was not subjected to toothbrush abrasion test. Average surface roughness (Ra) of each group was calculated using a surface roughness tester (Surfcorder MSE-1700: Kosaka Laboratory Ltd., Tokyo, Japan) . A representative specimen of each group was examined by FE-SEM (S-4700: Hitachi High Technologies Co., Tokyo, Japan). The data were analysed using cluster analysis, paired t-test, and repeated measure ANOVA. The results of this study were as follows; 1. Ra off group was $0.898{\pm}0.145{\mu}m$ and B-IM group was $0.289{\pm}0.142{\mu}m$. Ra became higher from B-1 group $(0.299{\pm}0.48{\mu}m$ to B-18 group $(0.642{\pm}0.313{\mu}m$. 2. Final cluster center of Ra was $0.361{\mu}m$ in cluster 1 $(B-IM\simB-7)$, $0.511{\mu}m$ in cluster 2 $(B-8\simB-14)$ and $0.624{\mu}m$ in cluster 3 ($(B-15\simB-18)$. There were significant difference among Ra of three clusters. 3 Ra of B-IM group was decreased 210.72% than Ra of F group. Ra of B-8 group and B-15 group was increased 35.49% and 51.35% respectively than Ra of B-IM group. 4. On FE-SEM, B-IM group showed the smoothest resin surface. B-8 group and B-15 group showed vertically shallow scratches , and wide and irregular vertical scratches on composite resin surface respectively. Within a limitation of this study, finished resin surface will be again smooth and glazy if BisCover would be reapplied within 8 to 14 months after applying to resin surface.

COLOR STABILITY OF THE RESIN CEMENTS WITH ACCELERATED AGING (레진시멘트의 색안정성에 대한 가속시험)

  • Song, Ha-Jeung;Park, Su-Jung;Hwang, Yun-Chan;Oh, Won-Mann;Hwang, In-Nam
    • Restorative Dentistry and Endodontics
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    • v.33 no.4
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    • pp.389-396
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    • 2008
  • The purpose of this study was to evaluate the color stability of resin cements with accelerated test. Four dual curing resin cements: Panavia-F (KURARAY). Duolink (BISCO), Variolink-II (Ivoclar Vivadent), and RelyX Unicem (3M ESPE) and 1 self curing resin cement: Resiment CE (j. l. Blosser) were used in this study. In control group, Gradia Anterior (GC) composite resin and Tescera Dentin (Bisco) indirect composite were used. Ten disk shape specimens were made from each resin cement. The specimens were subjected to an accelerated aging process in a refrigerated bath circulator at 60$^{\circ}C$ for 15 and 30 days. Spectrophotometric analyses were made before and after 15 days and 30 days of accelerated aging time. The color characteristics ($L^*,\;a^*,\;b^*$) and the color difference (${\Delta}E^*$) of the specimens before and after immersion were measured and computed. Regardless of type of the resin cements, $L^*$ value was decreased and $a^*$ value was increased, but there were no significant difference. But $b^*$ value was increased significantly (p < 0.05). Tescera inlay showed least color change (p < 0.05), but Gradia showed notable color change after 15 days. After 30 days on accelerated aging, ${\Delta}E^*$ value was increased (Panavia-F < Variolink-II < Resiment CE < Duolink < Unicem) (p < 0.05). but there were no significant difference among Panavia-F, Variolink-II, and Resiment CE groups. After 30 days of accelerated aging, ${\Delta}E^*$ value of all resin cements were greater than 3.0 and could be perceived by the human eye.

The Landscape Organization of the Dodong-SeoWon in the Aesthetics of Moderation (중용(中庸)의 미학으로 살핀 도동서원(道東書院)의 경관짜임)

  • Rho, Jae-Hyun;Shin, Byung-Chul
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.30 no.4
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    • pp.44-55
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    • 2012
  • This study is to interpret how landscape aesthetic characteristics of moderation, which is the point of human-oriented neo-confucianism vision, are projected to the landscape organization of a Dodong-SeoWon, known for its overflow to neo-confucianism grounds and standards among domestic SeoWon. The aspects of neo-confucianism discussion in the shape of Dodong-SeoWon with the beauty of from and contents dominating the landscape of Dodong-SeoWon different from constructive completeness as 7 external and internal landscape organization including placement, circulation, setting, vista, fencing, naming, and decoration are as follows. The left direction of Dodong-SeoWon, part of external organization, is the result of landscape organization that emphasized the stage of moderation through the unification of man and nature by naturalizing natural direction to human-oriented directions. Important aspects to rule external orders and standards of Dodong-SeoWon are principles of one classes based on ranks and bilateral symmetry that is the unity of setting and circulation landscape organization from penetrating the spirit of moderation with no bias. By securing territoriality by fencing the unity of verticality and horizontality, the landscape organization to reach moderation is expressed. Meanwhile, Suwoloo(水月樓) perceived on the floor of central assembly hall, the formation of time frame from roof piles of Hwanjumun(喚主門) as well as pilars of Jungjeongdang(中正堂), and rime link method inducing visual balance and openness through segment, combination, and others are vista organization that show the ideality of unique neo-confucianism building. Also as part of landscape organization contents. semantically, building name including arrangement from Taegukdoseol, ideological naming following the name of Ssanggye-SeoWon, which is the former body, the name of the hall symbolizing the transfer of neo-confucianism enlightenment, impartiality with no bias, as well as Geoinjae(居仁齋) and Geoijae(居義齋) based on olympic, are also results of applying neo-confucianism standards. Additionally. the SeoHoe(瑞花) expressing the change of IleumIlyang(一陰一陽) on the stylobate of Jungjeongdang, Saeho(細虎) which goes up and down, as well as Simul made of four dragons, are artistic expression of the moderation that symbolizes the harmony of ying and yang with no exceeding or insufficiency. Humorous and unique rocks and stones evenly arranged in all spots of Dodong-SeoWon are to promote anti-strict organization by offsetting the image and external order of the lecture hall as strict as it is, and this is very ironic as it is the other landscape organization in different dimension as well as the expression of moderation.