• Journal of Periodontal and Implant Science
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• v.29 no.3
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• pp.621-636
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• 1999

When mucoperiosteal flaps are positioned and sutured to desirable position, the wound contains several interface between tissues which differ fundamentally in composition & biological reaction. Thus the C-T surface of the flap will, on one hand, oppose another vascularized surface, and on the other, the avascular dental material for example, when root resoptions, fractured root, endodontic perforation, deep root carious lesions were filled with amalgam, glass ionomer, resin etc. Recently, a number of case report described the successful treatment of a subgingival root lesion with restorative material & free gingival graft, open flap surgery, but more objective research was needed . Most of study on restorative materials were concerned for cytotoxicity not for actual healing event on that materials and its influencing factors such as biocompatibility, surface wettability, surface topography . The aim of this in vitro study was to evaluate the effect of amalgam, resin modified glass ionomer, composite resin per se, and their surface roughness on the growth of human gingival fibroblast. The cells were obtained and placed on culture flask and incubated for 3 days with the prepared test materials. Then count the attached cell number with hemocytometer,(n=12) and 2 samples were examined with SEM about attachment cell morphology . Another 4 samples were evaluated on their surface roughness with Talysurf and average surface roughness value(Ra) were obtained. Statistical difference in attached cell number, roughness value were analyzed using ANOVA. The number of attached cell was as follows, for root dentin specimen 16.7${\pm}$4.41, resin modified glass ionomer 14.0${\pm}$4.15, resin 8.13${\pm}$3.63, amalgam 0.72${\pm}$3.33(${\times}10^3$). Between root dentin and resin-modified glass ionomer, no significant difference was observed, but resin, amalgam showed a significant less cell numbers than for root dentin, resin modified glass ionomer cement. SEM examination expressed many cell surface attachment apparatus in root dentin and resin modified glass ionomer specimens. For resin specimen, cell attachment was observed but exposed less appratus. The average surface roughness value are following results. Dentin specimen 0.6972${\pm}$ 0.104, resin modified glass ionomer 0.0822${\pm}$0.009, resin 0.0875${\pm}$0.005, amalgam 4.2145${\pm}$0.985(${\mu}m$). Between root dentin, resin-modified glass ionomer, and resin, no significant difference was observed, but amalgam showed a significant more rough surface than other groups. When evlauated the interrelationship between cell attachment and surface roughness, therefore, there was weak reverse correlation.(pearson correlation : - 0.593) These results suggest that resin modified glass ionomer have the favorable healing potential when used for subgingival restoration. And for relationship between cell attachment and surface characteristics, further investigations were needed.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.2
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• pp.1-10
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• 1996

The objective of this paper is to develop a motion base for the vehicle driving simulator. Kinematic analysis are carried out to obtain maximum strokes and velocities of hydraulic actuators. Hydraulic control forces of the actuators are estimated by inverse dynamic analysis. Finally, an optimal design is performed to find attachment points of the actuators so that control forces are minimized. A control logic for the motion base is developed to make the motion base follow the given reference signals. The control logic is implemented on a digital signal processor(DSP) board.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.04a
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• pp.105-110
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• 2003

The hydraulic excavator has been a popular research object for automation because of its multi-workings and economic efficiency. When it works crane tasks, most of disasters happen. The objective of this paper is to design each components and to construct boom, arm, bucket circuit. These models modeled with AMESim show us change of variables and behavior of excavator. Simulation model will be used for simulator of excavator.

• The Journal of Korean society of community based occupational therapy
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• v.7 no.2
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• pp.9-18
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• 2017

Objective : This study was to find out the level of sensory process type, adult attachment and interpersonal problems on university students and then to investigate the correlation. Methods : For this study, 169 students who don't know about the evaluation tool in university students of K area in Korea were participated. To execute evaluation, Adolescents/Adults Sensory Profile (AASP) was used for the sensory process type, Short Form of the Korean Inventory of Interpersonal Problems Circumplex Scale (KIIP-SC) was used for interpersonal problems, and Experiences in Close Relationships Scale-Revised (ECR-R) was used for the adult attachment. The correlation between sensory process type and interpersonal problems, adult attachment was analyzed by using pearson correlation analysis. Results : Sensory process type of university students appeared that sensory seeking was lower than general people, and the rest of items showed similar results with general people. For interpersonal problems, there was a lot of difficulty in self-sacrificing and overly accommodating, whereas there was a little difficulty in vindictive and domineering / controlling. For adult attachment, attachment avoiding was more stable than attachment anxiety. Also, low registration and sensory sensitivity all showed positive correlation with interpersonal problems and adult attachment. Among interpersonal problems, self-sacrificing and intrusive showed positive correlation with sensory seeking whereas cold, socially inhibited, nonassertive, and overly accommodating showed positive correlation with sensory avoiding. Thus, sensory seeking and sensory avoiding showed different results (p<.05). Conclusion : In occupational therapy clinic, not only the disabled but non-disabled people that experience issue of interpersonal problems and attachment could be helped with managing high quality social activity if they execute intervention according to sensory process type.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.1
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• pp.19-27
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• 2009

Globally, customer appreciation and demand for quieter products has driven noise control engineers to develop efficient and quieter products in a relatively short time. In the vehicles and ship industry, noise has become an important attribute because of the competitive market and increasing customer awareness. Noise reduction is often achieved through structural modifications by typical approaches. In the present paper, author describes a fundamental study on optimum design of curvature. Bezier curve. and rib attachment to reduce noise from simple panel using a genetic algorithm(GA). The acoustic optimization procedure employed p-FEM for structural analysis, the Rayleigh integral method for acoustic analysis and the GA for searching optimum design. In the optimization procedure. the objective function to be minimized is the average sound power radiated from an objective structure over a given frequency range $0{\sim}300$ Hz.

• The Journal of Advanced Prosthodontics
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• v.6 no.5
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• pp.406-414
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• 2014

PURPOSE. The objective of this study was to investigate the biologic effects of enamel matrix derivative (EMD) with different concentrations on cell viability and the genetic expression of human gingival fibroblasts (HGF) to zirconia surfaces. MATERIALS AND METHODS. Immortalized human gingival fibroblasts (HGF) were cultured (1) without EMD, (2) with EMD $25{\mu}g/mL$, and (3) with EMD $100{\mu}g/mL$ on zirconia discs. MTT assay was performed to evaluate the cell proliferation activity and SEM was carried out to examine the cellular morphology and attachment. The mRNA expression of collagen type I, osteopontin, fibronectin, and TGF-${\beta}1$ was evaluated with the real-time polymerase chain reaction (RT-PCR). RESULTS. From MTT assay, HGF showed more proliferation in EMD $25{\mu}g/mL$ group than control and EMD $100{\mu}g/mL$ group (P<.05). HGFs showed more flattened cellular morphology on the experimental groups than on the control group after 4h culture and more cellular attachments were observed on EMD $25{\mu}g/mL$ group and EMD $100{\mu}g/mL$ group after 24h culture. After 48h of culture, cellular attachment was similar in all groups. The mRNA expression of type I collagen increased in a concentration dependent manner. The genetic expression of osteopontin, fibronectin, and TGF-${\beta}1$ was increased at EMD $100{\mu}g/mL$. However, the mRNA expression of proteins associated with cellular attachment was decreased at EMD $25{\mu}g/mL$. CONCLUSION. Through this short term culture of HGF on zirconium discs, we conclude that EMD affects the proliferation, attachment, and cell morphology of HGF cells. Also, EMD stimulates production of extracellular matrix collagen, osteopontin, and TGF-${\beta}1$ in high concentration levels. CLINICAL RELEVANCE. With the use of EMD, protective barrier between attached gingiva and transmucosal zirconia abutment may be enhanced leading to final esthetic results with implants.

• Journal of Periodontal and Implant Science
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• v.46 no.2
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• pp.84-95
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• 2016

Purpose: The objective of this study was to investigate the effect of a dietary flavonoid, kaempferol, which has been shown to possess antiallergic, anti-inflammatory, anticarcinogenic, and antioxidant activities on the periodontium by histomorphometric analysis and on gingival tissue matrix metalloproteinase-1 (MMP-1), MMP-8, and tissue inhibitor of metalloproteinase-2 (TIMP-2) by biochemical analysis of rats after experimental periodontitis induction. Methods: Sixty Wistar rats were randomly divided into six groups of ten rats each, and silk ligatures were placed around the cervical area of the mandibular first molars for 15 days, except in the healthy control rats. In the experimental periodontitis groups, systemic kaempferol (10 mg/kg/2d) and saline were administered by oral gavage at two different periods (with and without the presence of dental biofilm) to all rats except for the ten non-medicated rats. Alveolar bone area, alveolar bone level, and attachment level were determined by histomorphometric analysis, and gingival tissue levels of MMP-1, MMP-8, and TIMP-2 were detected by biochemical analysis. Results: Significantly greater bone area and significantly less alveolar bone and attachment loss were observed in the kaempferol application groups compared to the control groups (P<0.05). In addition, gingival tissue MMP-1 and -8 levels were significantly lower in the kaempferol application groups compared to the control groups and the periodontitis group (P<0.001). There were no statistically significant differences in TIMP-2 levels between the kaempferol and saline application groups (P>0.05). Conclusions: Kaempferol application may be useful in decreasing alveolar bone resorption, attachment loss, and MMP-1 and -8 production in experimental periodontitis.

• Anxiety and mood
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• v.13 no.2
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• pp.115-122
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• 2017

Objective : The experiences in close relationships questionnaire-revised (ECR-R) (Fraley, Waller & Brennan, 2000) is a valuable tool for measuring adult attachment, and its Korean version, the ECRR-K (Kim, 2004), is widely used in Korea. However, given its substantial length, this study was aimed to develop and validate a short version of the ECRR-K called the ECRR-K14. Methods : Two hundred and ninety-four medical students participated in this study in 2016. They completed the ECRR-K, the Perceived Stress Scale (PSS), the Rosenberg Self-Esteem Scale (RSES), and the UCLA Loneliness Scale (UCLA-LS). The study authors applied the Rasch rating scale to check each item's model fit and then performed confirmatory factor analyses (CFAs) to test the new scale's validity. Results : The authors selected seven items each for the anxiety and avoidance subscales, and the ECRR-K14 showed fair to good internal consistency (Cronbach's ${\alpha}=0.93$ and 0.92 for anxiety and avoidance, respectively). The anxiety subscale showed concurrent validity with the PSS and the RSES while the avoidance subscale showed concurrent validity with the UCLA-LS. The CFAs also demonstrated the validity of the model with a goodness-of-fit index of 0.916. Conclusion : The ECRR-K14 showed excellent reliability and validity and appears to be a promising instrument for measuring the two attachment dimensions in adults.

• Journal of Korean Society for Quality Management
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• v.52 no.1
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• pp.95-113
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• 2024

Purpose: This study focused on the societal changes associated with the entry into an ultra-aged society and the increase in single-person households. The core objective of this research is to investigate how social intelligent robots can bring about positive changes in the lives of individuals in single-person households and how such changes influence user satisfaction and the intention to use these robots. Methods: The study employed a cross-sectional analysis using a structural equation model. A survey designed to assess the impact of social intelligent robots' characteristics, such as perceived encouragement, empathy, presence, appearance, and attachment, on user satisfaction and usage intentions was conducted. Data were collected from a total of 335 users and analyzed using the structural equation model. Results: In the characteristics of social intelligent robots for single-person households, it was found that empathy, presence, and attachment significantly influenced satisfaction, while perceived encouragement, empathy, and attachment significantly influenced usage intentions. The research results indicate differences between enhancing user satisfaction and increasing the intention to use social intelligent robots. The findings suggest the essential need for a user-centric approach in the design and development of social intelligent robots. Additionally, it was observed that emotional support plays a crucial role in users' experiences with social intelligent robots. Conclusion: This study verified the impact of social intelligent robots on satisfaction and usage intentions based on users' experiences. It examined the influence of linguistic, visual, and personal characteristics of robots on user experiences, providing insights into how technological and human aspects of social intelligent robots interact to shape user satisfaction and usage intentions. Consequently, the study confirmed that social intelligent robots can bring positive changes to human life, emphasizing the necessity for the advancement of robot technology in a human-centric direction.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.10
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• pp.1497-1508
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• 2008

The objective of this study is to identify the types of relationship quality of department store fashion consumers. This study also aims to look at if consumers form different type of relationship quality with various relation partners. In this study, qualitative research was conducted on 25 female consumers to come to a comprehensive and in-depth understanding of fashion consumers' diverse loyal relationships. Fashion consumer's relationship quality consisted of 'self attachment', 'symbolic', 'trust', 'intimacy', 'compensational bind', and 'habitual alternative'. 6 relationship quality dimensions were distinguished according to each dimension's emotional involvement level and conscious activeness level of consumers. While self attachment was classified as emotional and active relationship quality, compensational bind and habitual alternative were typical relationship quality types of fashion store loyalty such as department store loyalty, thus classified as inertial and cognitive relationship quality type. This study might provide a useful direction to apparel brands and retailers in finding out which relationship quality type is more effective for differentiated marketing strategies.