• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2005.09a
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• pp.110-123
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• 2005

This paper proposes an intelligent method for the optimal load distribution of two cooperating robots(TCRs) using fuzzy logic. The proposed scheme requires the knowledge of the robots' dynamics, which in turn depend upon the characteristics of large flat panel displays(LFPDs) carried by the TCRs. However, the dynamic properties of the LFPD are not known exactly, so that the dynamics of the robots, and hence the required joint torque, must be calculated for nominal set of the LFPD characteristics. The force of the TCRs is an important factor in carrying the LFPD. It is divided into external force and internal force. In general , the effects of the internal force of the TCRs are not considered in performing the load distribution in terms of optimal time, but they are essential in optimal trajectory planning: if they are not taken into consideration, the optimal scheme is no longer fitting. To alleviate this deficiency, we present an algorithm for finding the internal-force factors for the TCRs in terms of optimal time. The effectiveness of the proposed system is demonstrated by computer simulations using two three-joint planner robot manipulators.

• Journal of Adhesion and Interface
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• v.22 no.2
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• pp.69-77
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• 2021

A variety of efforts are attempted to make the world sustainable in fabrication industries worldwide. To achieve the goals, a new design concept for products is one of crucial factors to be able to dismantle them after use in easy and simple ways. New debonding technologies have been developed in recent years for the recycle and/or repair of bonded structures, where the bonds are broken without the damage of the components and make recycling easier. Some representative technologies of controlled delamination materials (CDM) are reviewed with an emphasis on light induced debonding of adhesives. We also describe current applications of light induced CDMs as temporary bondable films in semiconductor and display industries.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.12
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• pp.123-128
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• 2021

Liquid dispensing systems are extensively used in various industries such as display, semiconductor, and battery manufacturing. Of the many types of dispensers, drop-on-demand piezoelectric jetting systems are widely used in semiconductor industries because of their ability to dispense minute volumes with high precision. However, due to the problems of nozzle clogging and undesirable dispensing behavior in these dispensers, which often result in device failure, the use of highly viscous fluids is limited. Accordingly, we studied the behaviors of droplet formation based on changes in viscosity. The effects of surface energy and the inner diameters of needle-type nozzles were also studied. Results showed that nozzles with lower surface energies reduced the ejection volume of droplets when a smaller nozzle diameter (0.21 mm in this study) was applied. These results indicate that the hydrophobic treatment of nozzle surfaces and the use of smaller nozzle diameters are critical factors enabling the use of highly viscous fluids in precision dispensing applications.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.2
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• pp.65-75
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• 2021

Medication-related osteonecrosis of the jaw (MRONJ) has recently associated to the increase in antiresorptive and anti-angiogenic drugs prescriptions in the treatment of oncologic and osteoporotic patients. The physiopathogenesis of MRONJ remains unclear and available treatments are unsatisfactory. Newer pharmacological treatments have shown good results, but are not curative and could have major side effects. At the same time as pharmacological treatments, mesenchymal stem cells (MSCs) have emerged as a promising therapeutic modality for tissue regeneration and repair. MSCs are multipotential non-hematopoietic progenitor cells capable to differentiating into multiple lineages of the mesenchyme. Bone marrow MSCs can differentiate into osteogenic cells and display immunological properties and secrete paracrine anti-inflammatory factors in damaged tissues. The immunomodulatory, reparative, and anti-inflammatory properties of bone marrow MSCs have been tested in a variety of animal models of MRONJ and applied in specific clinical settings. The aim of this review is to discuss critically the immunogenicity and immunomodulatory properties of MSCs, both in vitro and in vivo, the possible underlying mechanisms of their effects, and their potential clinical use as modulators of immune responses in MRONJ, and to identify clinical safety and recommendations for future research.

• Journal of the Korean Society of Safety
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• v.36 no.2
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• pp.1-9
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• 2021

The 8200-unit electric locomotive, which is a high-efficiency multipurpose electric locomotive, is a German model, namely BR152 series ES64F, and it is manufactured to suit the operating conditions in Korea. Since 2003, 83 locomotives have been introduced in Korea, and they have been operating in the general railway sector for both passenger and freight transport. Although more than 15 years have passed since their first introduction, owing to the characteristics of vehicles introduced overseas, responding promptly to failures has been difficult owing to problems related to factors such as transfer of technology and procurement of parts for maintenance. Furthermore, there have been difficulties in operating the locomotives on the basis of the manufacturer-recommended time-between-overhaul (TBO) cycle. Therefore, a new TBO should be determined. To support the development of a reliability-based maintenance system, this study conducted a reliability and TBO analysis by using failure data obtained from KOVIS, and future management measures are presented.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.3
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• pp.429-438
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• 2021

The mandatory installation of the ECDIS (Electronic Chart Display and Information System) became an important navigational equipment for navigation officer. In addition, ECDIS is a key component of the ship's digitalization in conjunction with various navigational equipment. Meanwhile, cyber-attacks emerge as a new threat along with digitalization. Damage caused by cyber-attacks is also reported in the shipping sector, and IMO recommends that cybersecurity guidelines be developed and included in International Security Management (ISM). This study analyzed the cybersecurity hazards of ECDIS, where various navigational equipment are connected. To this end, Importance-Performance Analysis (IPA) was conducted on navigation officer using ECDIS. As a result, the development of technologies for cyber-attack detection and prevention should be priority. In addition, policies related to 'Hardware and Software upgrade', 'network access control', and 'data backup and recovery' were analyzed as contents to be maintained. This paper is significant in deriving risk factors from the perspective of ECDIS users and analyzing their priorities, and it is necessary to analyze various cyber-attacks that may occur on ships in the future.

• ALGAE
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• v.36 no.1
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• pp.13-24
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• 2021

The present-day genetic structure of macroalgal species reflects both geographical history and oceanic circulation patterns as well as anthropogenic introduction across native ranges. To precisely understand the genetic diversity and how the factors shape the current population structure of Gloiopeltis furcata sensu lato, we determined the mitochondrial 5' end of cytochrome c oxidase subunit I (COI-5P) sequences for 677 individuals sampled from 67 sites spanning almost the entire distribution range in Korea and Japan. Results from the phylogenetic analysis and haplotype distribution revealed eleven distinct lineages within G. furcata s.l. along the Korea-Japan coastal areas and displayed divergent phylogeographic patterns among lineages. Despite the closely related lineages distributed in same habitats as high rocky intertidal zone, they display different phylogeographic patterns among lineages. The populations from the south of Korea-Japan harbored the highest genetic diversity and unique endemism in comparison with other populations in the distribution range. This could be the evidence of southern refugia for G. furcata s.l. in the Northwest (NW) Pacific and the recent migration from native to introduced region. The reason is that an exceptional distribution pattern was found high genetic diversity in Hakodate of Japan where is the northern location in the NW Pacific. Our results imply the contemporary influence on the distribution due to current circulation pattern and anthropogenic effects. These phylogeographic findings provide the important insight into cryptic species diversity and the detailed distribution pattern of Gloiopeltis in the NW Pacific.

• Journal of Korean society of Dental Hygiene
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• v.22 no.3
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• pp.181-188
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• 2022

Objectives: This study aimed to estimate the influences of leader's political skills (LPS) on job satisfaction and organizational commitment in dental hygienists. Methods: A self-administrated questionnaire was conducted form April 1 to May 31 2020 by 209 dental hygienists in Seoul, Busan and South Gyeongsang. LPS, job satisfaction, organizational commitment were evaluated on the LPS scale, job descriptive index (JDI) and organizational commitment scale, respectively, each on five-point scale. Data were subjected to descriptive analysis, t-test, one-way ANOVA, pearson correlation and multiple linear regression analysis. Results: The overall LPS, job satisfaction and organizational commitment level of subjects were 3.53±0.63, 3.18±0.51 and 3.27±0.63. The influential factors for LPS, job satisfaction and organizational commitment were Networking ability (subcategory of LPS). Conclusions: Leaders should use the knowledge and activities newly introduced from various networks to fit the dental hospital so that members can display their more professional abilities to increase job satisfaction and organizational commitment.

• Science of Emotion and Sensibility
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• v.25 no.3
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• pp.107-116
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• 2022

Purpose: Researchers have shown that aesthetic judgments of artworks depend on contexts, such as the authenticity of an artwork (Newman & Bloom, 2011) and an artwork's location of display (Kirk et al., 2009; Silveira et al., 2015). The present study aims to examine whether contextual information related to the creator, such as whether an artwork was created by a human or artificial intelligence (AI), influences viewers' preference judgments of an artwork. Methods: Images of Impressionist landscape paintings were selected as human-made artworks. AI-made artwork stimuli were created using Google's Deep Dream Generator by mimicking the Impressionist style via deep learning algorithms. Participants performed a preference rating task on each of the 108 artwork stimuli accompanied by one of the two creator labels. After this task, an art experience questionnaire (AEQ) was given to participants to examine whether individual differences in art experience influence their preference judgments. Results: Setting AEQ scores as a covariate in a two-way ANCOVA analysis, the stimuli with the human-made context were preferred over the stimuli with the AI-made context. Regarding the types of stimuli, the viewers preferred AI-made stimuli to human-made stimuli. There was no interaction effect between the two factors. Conclusion: These results suggest that preferences for visual artworks are influenced by the contextual information of the creator when the individual differences in art experience are controlled.

• Fashion & Textile Research Journal
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• v.25 no.4
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• pp.481-489
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• 2023

This study aims to explore the relationships between self-esteem, sociality, appearance satisfaction, and subjective appearance satisfaction among college students. A self-administered questionnaire was used to survey students from 4-year colleges in Gwangju Metropolitan City. The findings reveal that personal self-esteem significantly impacts autonomy and activity, while social self-esteem significantly affects sociability and activity. Both physical and psychological self-esteem exhibit a significant influence on sociability, autonomy, and activity, underscoring their pivotal role in shaping social interactions. Further, both social and physical self-esteem significantly affect subjective appearance satisfaction, while bearing no significant influence on personal and psychological self-esteem. Thus, all self-esteem factors influence subjective appearance satisfaction, although some are not statistically significant. In addition, both sociability and activity display a statistically significant influence, whereas autonomy exhibits no such significance. This underlines the centrality of subjective appearance satisfaction in fostering sociability and activity. In sum, the outcomes underscore the interconnectedness of self-esteem, sociality, and subjective appearance satisfaction in college students. Moreover, the results indicate that higher subjective appearance satisfaction is linked with increased perceptions of self-esteem and sociality. Therefore, the development of programs oriented toward enhancing self-esteem and sociality among college students is imperative, enabling them to navigate their academic and social experiences with self-assurance.