• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.373-376
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• 2000

Recently, the life cycle of products is rapidly shortened and then the W s a l of the used mold applied in development of a product is a difficult things. In this study, we proposed a feasibility of the recycling mold base by analyzing of the existing standard mold base. And we developed a D/B program to promote the mold design capability with CAD. Also, we confirmed the possibility of recycling mold base by testing of a used automobile lamp mold.

• International Journal of Stem Cells
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• 제16권2호
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• pp.202-214
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• 2023

Background and Objectives: To investigate the role of exosomes from periodontal ligament cells (PDLCs) in bone marrow mesenchymal stem cell (BMSC) migration. Methods and Results: Human PDLCs were applied cyclic tension stretching. Exosomes were extracted from cultured PDLCs by ultracentrifugation, then characterized for their size, morphology and protein markers by NTA, TEM and western blotting. The process that PKH26-labeled exosomes taken up by BMSCs was assessed by confocal microscope. BMSC migration was examined by Transwell assay. Exosomes derived from PDLCs were identified. Cyclic tension stretch application on PDLCs can enhance the migration ability of BMSCs through exosomes. The exosomal miRNA expression profiles of unstretched and stretched PDLCs were tested by miRNA microarray. Four miRNAs (miR-4633-5p, miR-30c-5p, miR-371a-3p and let-7b-3p) were upregulated and six (miR-4689, miR-8485, miR-4655-3p, miR-4672, miR-3180-5p and miR-4476) were downregulated in the exosomes after stretching. Sixteen hub proteins were found in the miRNA-mRNA network. Gene Ontology and KEGG pathway analyses demonstrated that the target genes of differentially expressed exosomal miRNAs closely related to the PI3K pathway and vesicle transmission. Conclusions: The exosomes derived from cyclic tension-stretched PDLCs can promote the migration of BMSCs. Alternation of microRNA profiles provides a basis for further research on the regulatory function of the exosomal miRNAs of PDLCs during orthodontic tooth movement.

• 한국주거학회논문집
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• 제27권4호
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• pp.47-58
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• 2016

As increasing demand for the living environment to promote social health, this study focused on consumers customized rental housing community space. Set the community spatial planning objectives and strategies shown in previous studies to the conceptual model for evaluation of community space. Based on the planning methods and standards of consumers custom community facilities, we analyzed the Seoul consumer customized public rental housing nine cases. Because almost located in the small vacant lot, they had limitations as a base for the local community. Nevertheless, through the arrangement of the building, Child care households increase the chance of contact with the neighbors. In elderly households, welfare facilities strengthen the character of as a base for local community. 1-2 person households situated close to the cultural facilities, by installing a hobby room and gym, was judged to be able to promote the community. Consumer custom rental housing community space evaluation items presented in this study, was set up by analysis of the conceptual model for evaluation of community space and implications of the 9 cases.

• 농촌계획
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• 제14권2호
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• pp.99-110
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• 2008

The purposes of this paper are first, to develop and adapt auditing methodology of rural amenity resource investigation and second, to propose strategic planning of amenity web data base system. Relating with auditing methodology, we make the life cycle of rural amenity resource investigation based on value chain method. we make 8 stage of auditing process and 105 auditing items in details. We adapt these guidelines in real world and then improve developed methodology. Therefore we expect to promote the quality and accuracy of investigation project using these guidelines. Relating with blue print of strategic planning, we first analyse external environment about Competitors, Suppliers, New entrants, Buyers, Substitutes with 5 force model for amenity information system. We second make the blue print of strategic planning of amenity web data base system project. Then we propose the FIRST, BEST, MOST strategy of amenity web data base system and the web hub system.

• 대한치과보철학회지
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• 제41권4호
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• pp.493-502
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• 2003

Statement of problem : Removable partial denture and complete denture often require denture base relines to improve the fittness against tissue-bearing mucosa because of the gradual change in edentulous ridge contour and resorption of underlyng bony structure. Self-curing hard reline resins offers the immediate and relatively inexpensive means to be recondition the surface of denture base directly However weak bond between denture base resin and reline material can harbor bacteria, promote staining, or result in complete separation of the two materials. Purpose : The purpose of this study was to evaluate the effect of denture cleansers on bond strength and surface hardness of reline resin to denture base resin Denture base resin beams($60.0{\times}15.0{\times}3.0mm$) were made with Lucitone 199. Material and methods : 10mm section was removed from the center of each specimen. The samples were replaced in the molds and the space of l0mm sections were packed with Tokuso Rebase reline material. The specimens were immersed in denture cleansers (Polident, Cleadent) and were evaluated after 1 week, 2 weeks, and 4 weeks. The bond strength and surface hardness of self-curing hard reline materials to heat-curing denture base resin were measured using an UTM (universal testing machine). Results and conclusion : 1) There was no significant difference of usage, kind, and denture cleaner by application time on the bonding strength of self-curing hard reline resin to denture base resin. 2) There was no significant difference of usage, kind, and denture cleaner by application time on the surface hardness, but the surface hardness showed decreasing tendency, as the time of immersion was extended. 3) The failure modes of the specimens was initially adhesive failure and finally cohesive failure of self-curing hard reline resin.

• 대한치과교정학회지
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• 제23권4호
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• pp.633-644
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• 1993

There has been so much controversies about the position of upper and lower jaws, and their first permanent molars in normal occlusion and Angle's class $I{\cdot}II{\cdot}III$ malocclusions. So, the purpose of this study is to compare the position of upper and lower jaws, and their first molars in normal occlusion and Angle's class $I{\cdot}II{\cdot}III$ malocclusions by lateral cephalometric analysis. The sample consisted of one hundred and twenty girls(thirty in each group) who had completed growth. The findings of this study were as follows : 1. In class I malocclusion, both maxilla and mandible were slightly posterior position than normal occlusion, but they showed harmonious relationship. 2. In class II malocclusion, the mandible was greatly retruded, and the maxilla was also slightly retruded to the cranial base as compared with normal occlusion. 3. In class III malocclusion, the maxilla was significantly retruded to the cranial base, but no significant difference was found in mandibular position as compared with normal occlusion. 4. The maxillary first molar was located at posterior position in class II malocclusion, and anterior position in class III malocclusion to the cranium, so that the rotation of mandible was influenced by that. 5. The mandibular first molar showed constant relationship to the mandible in all four groups, but different position to the cranial base in direct proportion to the mandibular position. 6. On the treatment planning of class III malocclusion, it seems to be better to promote the mandibular horizontal growth by inhibiting the vertical growth of maxillary molar area, and on the treatment planning of class III malocclusion, it seems to be better to promote the antero-inferior growth of maxilla mi to promote the mandibular vertical growth by inducing the vertical growth of maxillary molar area.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 가을 학술발표회 논문집
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• pp.64-69
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• 1996

As Waste-concretes generated in construction field are increasing, it is becoming difficult and expensive to dispose them. For environmental reasons, many attempts have been made to find ways of reusing these materials. However, very little waste-concrete is currently recycled or reused anywhere on the world. Recycled concrete is mainly used as nonstabilized base of sub-base in highway construction. In this study, in order to promote the reuse of the waste-concretes, no-fines concrete blocks using recycled concrete aggregates were produced and their properties are evaluated. From the test results about strengths, pemeability, and durability, it is known that to use recycled aggregates for construction goods is promising and economical.

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1537-1540
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• 2013

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2005년도 공동추계학술대회
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• pp.157-162
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• 2005

Seamlessness is the Keyword of U-Commerce Which may be defined as the commercial interaction among providers, consumers, products, and services, enabled and supported especially by the real-world seamless communication of each entity and object's digital information. However, the possibility of the seamless transactions increases the privacy risk of the entities involved. Therefore, the core issue of U-Commerce is how to promote seamless transactions while protecting the privacy. for the seamlessness, the role of incentive-emphasized business model is important since the seamlessness makes clear which economic entities contribute to a commercial transaction. Economic entities will reject the seamless transactions unless the sufficient incentives are given to them. In order to consider the privacy issue, we suggest an alternative U-Commerce architecture based on Hybrid P2P Model and Personal Information Base.

• 디지털융복합연구
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• 제6권4호
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• pp.157-163
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• 2008

Despite the increase internet use rate, there still appears a big difference in web usage rates depending on demographic variables, web usage environment variables. This study aimed to improve our understanding of perceived usage, attitude, affected factors related Web usage for schoolwork and research. This result will facilitate further understanding of perceived usage, attitude, affected factors related Web usage, thereby enabling researchers, practitioners, and policy makers to better design appropriate strategies to promote the Web usage.