• Journal of Dental Rehabilitation and Applied Science
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• v.18 no.4
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• pp.313-320
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• 2002

The purpose of the present study was to evaluate the marginal discrepancy and topography of artificial crown on teeth extracted due to severe periodontal disease. Twenty specimens were invested into metamethylacrylate resin and cutted into vertical slices along with the long axis of tooth. The selected marginal discrepancy between the outer edge of the crown and the finishing line of abutment was examined by stereo- microscope(Olympus, PM-VSP-3, Japan) at magnification of up to 10, and the topography of finishing margin on crown was observed by stereomicroscopeat magnification of up to $70{\times}$. The results were as follows. (1) The mean marginal discrepancy between extracted tooth and artificial crown were $50.82{\mu}m$. (2) There was a considerable difference in the microstructure of finishing margins among specimens. Microscopic Structure on finishing margin showed indefinite line, poor fit (open, underextended and overextended), distorted margin, and surface roughness. This study suggested that there could be necessary to consider the response of periodontium to the emergence profile of natural tooth and precision of marginal geometry while establishing treatment planning for the reconsruction of the artificial crown.

• The Journal of the Korean dental association
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• v.54 no.3
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• pp.191-197
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• 2016

In the past, restoration of implant crown, ready-made abutment produced by implant manufacturer could only be used. Using straight, angled abutment, there was a limit in adaptation multiple implants. Recently, with the development of implant and CAD/CAM technology, CAD/CAM customized abutment use has become possible which is different from the past when restoration was possible with only prefabricated abutment. Not only it makes emergence profile possible which is similar to natural teeth, but also it makes insertion path possible on CAD in multiple implant restorations. However, on anterior teeth which dental esthetics is very important, another restorations which are formed with natural colored gingiva area could be required. Titanium-based zirconia prostheses which have titanium connection and zirconia structure from 1mm above fixture platform are alternative. Therefore, the purpose of this review is to analyze the characteristics, advantages and disadvantages of the abutment which is used in multiple implant restorations, and to choose right abutment when clinical trials.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.4
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• pp.251-265
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• 2013

The emergence of social network services, is changing the foundation of human relationship formation and method of communication of individuals through sharing of free information. Social network service is a service to support or facilitate an on-line extension of off-line network among people by helping them to share personal profile. History of social network services very short. But users of the various layers is increasing rapidly and ripple effect social as a result is very large. The focus of existing research was mainly devoted to motivation of use and acceptance of social network services. Currently the use of SNS was maturing. Thus, in-depth research on the use pattern of SNS users is needed. The purpose of this study is that, for Facebook in social network services, to analyze the changes in the initial stage of use, medium-term, usage patterns at the current time. Results of the study by analyzing the characteristics of the change in the pattern of usage of user of Facebook, it can be used as basic materials for SNS researchers and service provider.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.29 no.1
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• pp.13-24
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• 2020

Autotransplantation is the surgical repositioning of an autogenous erupted or unerupted tooth from one site to another in the same individual. This treatment is indicated in traumatic tooth loss, teeth with severe caries, congenitally missing teeth, teeth with bad prognosis and in case of developmental anomalies of teeth. The following 2 cases describe the potential to utilize autotransplantation to replace hopeless teeth with sound wisdom teeth.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.700-708
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• 2012

In order to optimize a method to determine the firmness of Chinese cabbage, hardness of midrib tissues was examined based on their chronological order of emergence. Texture measurement using volodkevich bite jaws gave a consistent and highest regression ($r^2=0.85$) between firmness and the order of leaf emergence, while blade set, cylinder probe, and crisp fracture support rig showed a lower coefficient of determination. Thickness of midrib tissue within an individual head from 16 cultivars of Chinese cabbage was positively correlated with the order of emergence, becoming thinner toward inner leaves. Mean thickness of midrib tissue from the head ranged from 7.74 mm for 'CR-shingshing' and 9.28 mm for 'Norangyeorum'. The covariance of leaf thickness within a head was highly cultivar-dependent, ranging from 23.6% for 'Chihili' and 5.8% for 'Bulam'. Firmness of the midrib tissue, defined as maximum peak height per tissue thickness, became higher from outer to inner leaves, showing $2^{nd}$ order of regression. Mean firmness of the midrib tissue from individual head varied from 1.58 N for 'Rangno' to 3.46 N for 'CR-shingshing'. The $10^{th}$ or $11^{th}$ leaf brought the best correlation coefficient (r = 0.81) between firmness of an individual leaf and the mean firmness of the entire leaves in a head, suggesting a reliable and rapid method to estimate the firmness of a head in lieu of examining all leaves in the head. The relationship between firmness of midrib tissue and dry mass ($r=0.70^{**}$) as well as cell wall content ($r=0.58^*$) of the head were positively correlated. Results obtained from the present study suggested that a new method to determine midrib firmness would enable to clarify the relationship between textural quality of fresh Chinese cabbage and their processed product, 'Kimchi'. It will also be important to apply this method to screen textural quality of various genotypes under breeding programs.

• Journal of Service Research and Studies
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• v.1 no.1
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• pp.29-48
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• 2011

Recently not only industry but also academy have shown an intense interest in social networking service. However, reckless imitation will not guarantee the successful eco-system of social networking service without rich understanding of growth driver and business model. Hence, this study aims at analyzing open platform strategy and business model conducted by a representative social networking service provider in order to provide platform operator, network operator, and portal provider with meaningful implications. Advertisers may pay great attention to social networking service because it has strong ability to provide users with spontaneous motivation to manage and update their profile, and these valuable information can be utilized for providing personalized advertisement on social networking service. As a result, one side of consumers in two side market, advertisers, tend to pay more expenditure to place advertisements. In addition, the open platform adopted by social networking service providers causes pro-sumers to participate in the eco-system, and thereby the explosive quantitative growth is realized. The fact of that this open social networking service can invade other web service area via an unified platform indicates that it may expand its service scope into a wide variety of web service areas. Hence, domestic portal services providers and network providers should consider social networking service not as one of new web services but as an disruptive service platform. Corresponding to the emergence of social networking service, especially if their business area is related to display advertising market, they should seek a way to provide social networking service access users's newly updated information and develop innovative media technologies to enter context awareness ads market.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.3
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• pp.260-269
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• 1986

This experiment was conducted to investigate the effect of mulching materials on the emergence rate, root dry weight and grain weight of sesame using variety Poong Nyun Ggae and also their effects on physical properties of soil, evapotranspiration and weed growth on the respective plots were studied. The effect of soil water holding capacity at mulching with polyethylene film and straw increased 5.4%, 2.8% to non-mulched plot respectively. The maximum soil temperature was raised up to 4$^{\circ}C$ by applying clear film and was dropped down to 7$^{\circ}C$ by straw. The minimum soil temperature was raised up to 2$^{\circ}C$ by clear film and was dropped down to 3$^{\circ}C$ by straw. In the early stage, the soil physical properties of clear film mulching were better than those of non mulching, and so was in emergence rate. In the late stage, soil strength was high at non mulching, and soil porosity, soil aeration and water infiltration rate were high at film and straw mulchings. Total root dry weight was great at clear film mulching, and root dry weight was concentrated mainly in the upper 10 cm of soil profile. The amount of weeds collected was the least at black film mulching. There were of little difference in evapotranspiration among treatments. The grain yield of sesame was increased to 57% by polyethylene film and 25% by straw mulching.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.6
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• pp.35-50
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• 2017

This study is to see the recovery effect of the Deltacon method by investigating the amount of sand deposition, the topographical cross section and the vegetation structure; and to derive the effective recovery method of coastal erosion area. The target areas of this study include Jinri coastal dune, Bajireum coastal dune and Seopori coastal dune in Deokjeok-do Island, Ongjin-gun, Incheon. In order to assess the current status of the coastal erosion area recovery, the soil profile structure map was prepared on the site and then the amount of sand deposition within 1m was calculated indoors. The vegetation recovery status of the costal erosion area was assessed via the analyses of the topographical profile structure and the plant community structure, and we aim to derive the effective recovery plan of the Deltacon method with the results. With the Deltacon method, structures with ductile material, special non-woven fabric bags filled with soil and vegetation can be performed therefore the structuralstability and prevention of sand erosion can be achieved. The amounts of sand deposition of Bajireum coastal dune, Seopori costal dune and Jinri costal dune were calculated $0.98{\sim}2.54m^3$, $1.02{\sim}2.96m^3$, and $0.27{\sim}0.75m^3$, respectively, and it is considered that the costal erosion recovery is actively performed for Bajireum costal dune and Seopori costal dune. The analysis results of vegetation structures by topography show that the installation of the send collecting net in steep areas has been highly effective and the Deltacon-constructed target areas have been restored to vegetation and the costal dune, which is similar to the natural dune. The investigation of the plant community structure in Deokjeok-do Island costal dune, Incheon displayed similar research results of the existing costal dune flora and confirmed the emergence of Lathyrus japonicus, Carex kobomugi, Elymus mollis, Vitex rotundifolia, and Calystegia soldanella and others. In order to carry out further effective recovery with the Deltacon method, improvements to rootage of herbaceous vegetation are needed in areas without foredune herbaceous vegetation, and continuos maintenance & management monitoring of connected windbreak forest to costal dunes are also necessary.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.3
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• pp.222-227
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• 2015

Aesthetic impression is emphasized in the recent field of implant restoration. However, there is limitation of creating proper shape of soft tissue as well as cervical emergence profile due to the use of pre-existing healing abutment in the process of initial post-operative soft tissue healing period. Designing the shape of abutment into the final customized abutment instead of its original shape helped to achieve more aesthetic implant restoration by applying healing abutment which could minimize the malposition and recession of soft tissue. In this study, soft tissue healing was promoted using the post-operative customized healing abutment and thereby obtained the result of more aesthetic and functional restoration by minimizing displacement of soft tissue in the process of applying final customized abutment.

• Mycobiology
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• v.43 no.3
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• pp.303-310
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• 2015

The increasing emergence of lead drugs for the resistance produced by the pathogenic strains and arrival of new diseases have initiated the need for searching novel metabolites with best anticancer and antimicrobial properties than the existing one. With this view, the investigation was conducted for the isolation, identification, and biological evaluation of potential endophytic fungi of Aegle marmelos, a medicinal tree used for more than three decades, for curing various disorders. A total of 169 endophytic fungal strains obtained from sampling and among those 67 were pigmented strains. Upon antagonistic screening, five endophytic fungal strains exhibited antagonistic potentiality by inhibiting the pathogens. These five potent strains were characterized at molecular level by sequencing the amplified internal transcribed spacer (ITS) 1 and ITS 4 regions of rDNA and they were grouped under order Pleosporales, Eurotiales, and Capnodiales. The metabolites from the respective strains were produced in fungal culturing media and extracted using polar solvents. Further, the extracts of five endophytes manifested antimicrobial activity against tested clinical pathogens and Alternaria alternata (FC39BY), Al. citrimacularis (FC8ABr), and Curvularia australiensis (FC2AP) exhibited significant antimicrobial profile against 9 of 12 tested pathogens, showing broad spectrum activity. The antioxidant levels of all the five endophytes revealed the highest activity at least concentrations, and major activity was unveiled by the members of order Pleosporales FC2AP and FC8ABr. This research explains the value of endophytic fungal extracts and its significance of antimicrobial and antioxidant properties.