• Journal of Korea Entertainment Industry Association
• /
• v.14 no.7
• /
• pp.79-94
• /
• 2020

The purpose of this study is to analyze the difference in the effect of presence for the activation of virtual reality sports on participation satisfaction, to suggest continuous screen golf exercise participation, and to provide empirical and academic data for the development of the entire virtual reality sports market. To achieve this purpose, the survey period was from March 13 to May 13, 2020, with five researchers and assistants. The purpose of this study and the questionnaire were fully explained to consumers who experienced screen golf directly, and 247 questionnaires were used as the final valid sample by making a questionnaire with self-administration method. The data processing method was the statistical program Windows SPSS 18.0. First, factor analysis and reliability analysis, second, frequency analysis mean(M) and standard deviation(SD), third, Scheffe analysis among t-test and One-way ANOVA analysis, fourth, correlation analysis between variables and multiple regression analysis were conducted. The results of this study through these methods and procedures are as follows. First, there was a significant difference in participation satisfaction of presence in gender, and participation period of general characteristics. Second, there was a high difference in social presence, social self-reliance, and Ego, which are sub-factors of Presence, in social satisfaction, psychological satisfaction, and physical satisfaction. Third, the sub-factors of Presence, Social Presence, Social Self-Reliance, and Ego, were found to have a high effect on the sub-factors of Participation Satisfaction, Social Satisfaction, and Psychological Satisfaction.

• Analytical Science and Technology
• /
• v.34 no.6
• /
• pp.275-283
• /
• 2021

This study presents the development of cell-based microfluidic chips for the performance of acute eye irritation tests due to chemicals and examined some of their applications. Microfluidic chips were fabricated by photolithography and soft lithography, and they had three compartments with different areas for cell culture. Rabbit corneal epithelial cells were used for the eye irritation test. The death of cells cultured inside the chip was monitored at regular time intervals after treatment with an aqueous solution of chemicals, and the cell death rate constants were calculated based on the viability curve. The performance of the microfluidic chip was verified by examining the effects of cell-cell junctions, cell-substrate adhesion, and initial cell numbers compared to cell death rates. Eye irritation tests were performed at various concentrations of an aqueous solution of sodium dodecyl sulfate (SDS), a standard substance for the eye irritant test. The cells were exposed to the SDS aqueous solution for 300 s, and the resulting eye irritation was assessed by cell viability. Finally, the equation for calculating the toxicity score (TS) was derived based on the weighting factor for each compartment in the chip. The cell-based microfluidic chip developed in this study may be used for eye irritation tests from chemicals used in cosmetics and pharmaceuticals.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.27 no.7
• /
• pp.1124-1128
• /
• 2021

As regulations of emissions from ships become more stringent, electric propulsion systems have been increasingly used to solve this problem in vessels ranging from large merchant ships to small and medium-sized ships. Methods for improving the efficiency of the electric propulsion system include the improvement of power sources; the use of a system linked to environmentally friendly power sources, such as batteries, fuel cells, and solar power; and the development of hardware and control methodology for rectifiers, power conversion devices, and propulsion motors. The method using a phase-shifting transformer with diodes has been widely used for rectification. Power semiconductor devices with grid connection to an environmentally friendly power source using DC distribution, a variable speed power source, and the application of small and medium-sized electric propulsion systems have been developed. Accordingly, the demand for active front-end (AFE) rectifiers is increasing. In this study, a method using a neural network rather than a conventional proportional-integral controller was proposed to control the AFE rectifier. Tested controller data were used to design a neural network controller trained through MATLAB/Simulink. The neural network controller was applied to a rectification system designed using PSIM software. The results indicated the effectiveness of improving the waveform and power factor DC output stage according to the load variation. The proposed system can be applied as a rectification system for small and medium-sized environmentally friendly ships.

• Therapeutic Science for Rehabilitation
• /
• v.11 no.4
• /
• pp.41-53
• /
• 2022

Objective : The purpose of this study is to identify and analyze the vocational rehabilitation evaluation tool for the mentally disabled. Methods : For literature search, the Pubmed database was used, and for the analysis, the development year, evaluation method, number of items, scale, and evaluation items were analyzed. In the analysis method, each evaluation item was divided into four categories: function, internal factor, environment, and mental symptom, and the evaluation elements of each evaluation tool were identified. Results : When searching Pubmed through search terms, 161 documents were retrieved. According to the selection method, Griffiths Work Behavior Scale (GWBS), Occupational Functioning Scale (OFS), Social and Occupational Functioning Assessment Scale (SOFAS), Work Ability Index (WAI), Work Behavior Inventory (WBI), Work Environment Impact Scale (WEIS), and Work and Social Adjustment Scale (WSAS) were screened. The evaluation items of all evaluation tools included job-related functional evaluation. According to the purpose of each evaluation tool, internal factors, environment, and mental symptoms were measured. Conclusion : Occupational skills are skills in which various functions such as physical, cognitive, social skills, and coping skills act in a complex way. Therefore, it is necessary to include the four factors analyzed in this study: function, internal factors, environment, and psychiatric symptoms.

• The Korea Journal of Herbology
• /
• v.38 no.1
• /
• pp.11-19
• /
• 2023

Objectives : Neuroinflammation is a common pathological mechanism of neurodegenerative diseases, and the development of therapeutic agents is urgently needed. Red ginseng has been known to be good for the immune stimulation in Eastern Asia. Although the immuno-stimulatory activity of red ginseng are already known, the neuro-protective effects of cultivated red ginseng with fermented complex mushroom-cereal mycelium (RGFM) have not been conducted. Thus, in this study, we tried to investigate the anti-neuroinflammatory effect of RGFM water extract on lipopolysaccharide (LPS) stimulated BV2 cells. Methods : BV2 cells were pretreated with RGFM 1 h prior to LPS exposure. To determine the neuro-protective effects of RGFM water extract, we measured the expression of inflammatory mediators including inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2 and nitric oxide (NO) and pro-inflammatory cytokines such as interleukin (IL)-1𝛽, IL-6 and tumor necrosis factor (TNF)-𝛼 in LPS-stimulated BV2 cells. In addition, to find out the regulatory mechanism of RGFM water extract, we assessed the protein levels of mitogen-activated protein kinases (MAPKs) and inhibitory 𝜅B𝛼 (I𝜅B𝛼) by western blotting. Results : In our study, treatment of RGFM reduced the mRNA expression of iNOS and COX-2 and suppressed NO production in LPS-stimulated BV2 cells. Additionally, the secretion of IL-1𝛽 and TNF-𝛼 but not IL-6 was significantly inhibited by RGFM. Furthermore, RGFM water extract inhibited the phosphorylation of c-Jun N-terminal kinase (JNK). Conclusions : Taken together, these findings suggest that RGFM water extract has a protective effect on neuroinflammation through inhibition of JNK.

• Journal of Aerospace System Engineering
• /
• v.16 no.4
• /
• pp.60-67
• /
• 2022

An Electro-Optical Tracking System (EOTS) is an electric optical system with EO/IR cameras, laser sensors, and an IMU. The EOTS calculates coordinates of targets, using attitude and acceleration measured by the IMU. In particular for an armed aircraft, the performance of the weapon system depends on how quickly and accurately it acquires the target coordinates. The IMU should be operated after alignment is complete, to meet the coordinate accuracy required by the weapon system so the initial stabilization time of the IMU should be reduced, by quickly measuring the attitude and acceleration. Alignment is the process of determining the initial attitude by resolving the attitude error of the IMU, and the IMU of mission equipment such as an airborne EOTS, uses velocity matching based on the velocity from GPS/INS for aircraft navigation. In this paper, a method is presented to improve the transfer alignment performance of the airborne EOTS, by maneuvering aircraft and the mission equipment. First, the performance factor of the alignment was identified, as a heading error through the velocity matching model and simulation results. Then acceleration maneuvers and attitude changes were necessary, to correct the error. As a result of flight tests applied to an EOTS on a OOO aircraft system, the transfer alignment performance was improved as the duration time was decreased, by more than five times when the aircraft accelerated by more than 0.2g and the EOTS was moving until 6.7deg/s.

• Journal of the Korean Society for Library and Information Science
• /
• v.56 no.2
• /
• pp.231-254
• /
• 2022

Industrial heritage resources produced by industrial activities have historical and conservative values and value as cultural properties as they serve as a medium connecting the past, present, and future. In other words, Industrial heritage resources should be used, managed, and preserved simultaneously as important records and evidence for the future. Metadata is well known as a necessary and important factor for the use, management, and preservation of information resources. In particular, in order to describe various industrial heritage resources that have historical, cultural, and conservative values, metadata elements from various perspectives are needed to relate to the story, type etc. of data. Therefore, this study attempted to design metadata elements that can comprehensively describe different types of industrial heritage resources. And we designed metadata that suited for the purpose of using, managing, and preserving industrial heritage resources, through mapping and combination between industrial heritage-related metadata. As a result, metadata was grouped into five types(administrative, descriptive, preservation, technical, use) and prepared into a total of 25 higher & 86 lower elements.

• Journal of the Korean Regional Science Association
• /
• v.37 no.4
• /
• pp.49-59
• /
• 2021

This study aims to identify the characteristics of the cancelled districts of housing redevelopment and housing reconstruction project. The subject of this study is 189 project districts(121 promoted districts, 68 cancelled districts). Both 121 promoted districts and 68 cancelled districts were analyzed by Decision Tree Analysis. The first separation of the release zone influencing factors was made by the Development Actors. In other words, the most important independent variable for determining the release zone influence factor was shown to be the presence or absence of propulsion actors. Of the 89 districts without propellers, 41 were lifted and 48 were promoted, and 9 out of 100 districts with propellers were lifted and 91 were promoted. The second separation of the impact factors on the zone was then made by Land Owners, and the probability of cancellation increased if the number of landowners was less than 468 and 37 out of 62 were removed. On the other hand, four out of 27 districts with more than 468 landowners were lifted and 23 districts were promoted. The third separation was made by the Average Land Assessment, and 35 zones were lifted below the standard of KRW 269.64 million/m² approximately KRW 8.91 million per pyeong, and two zones were lifted at higher official prices. In the second division, the number of landowners was 468 or more, and in node4, four areas were removed from areas with a public land area ratio of 29.43% or more, and no areas less were released. This study used SPSS Statistics 26 S/W for analysis.

• Journal of Life Science
• /
• v.32 no.2
• /
• pp.94-100
• /
• 2022

Chronic infection by hepatitis B virus (HBV) greatly increases the risk for liver cirrhosis and hepatocellular carcinoma (HCC). The outcome of HBV infection is shaped by the complex interplay of the mode of transmission, host genetic factors, viral genotype, adaptive mutations, and environmental factors. The pregenomic RNA transcription of HBV for their replication is regulated by the core promoter activation. Core promoter mutations have been the reason for acute liver failure and are associated with HCC development. We obtained HBV genes from a patient in Myanmar who was infected with HBV and identified gene variations in the core promoter region. For measuring the relative transactivation activity of the core promoter, we prepared the core-promoter reporter construct. Among the gene variations of the core promoter, the mutations of C1731T and G1806A were associated with increase in the transactivation of the HBV core promoter. Through computer analysis for searching for a tentative transcription factor binding site, we showed that the mutations of C1713T and G1806A newly created C/EBPβ and XBP1-responsive elements of the core promoter, respectively. The ectopic expression of C/EBPβ largely increased the HBV core promoter containing the C1713T mutation and that of XBP1 activated the M95 promoter containing the G1806A mutation. Our efforts to treat and prevent HBV infections are hampered by the emergence of drug-resistant mutations and vaccine-escape mutations. Our results provide the biological properties and clinical significance of specific HBV core promoter mutations.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.21 no.4
• /
• pp.190-211
• /
• 2022

This study investigated the effect of the shape and height of road signs on detection performance when detecting road signs with LiDAR, which is recognized as an essential sensor for autonomous vehicles. For the study, four types of road signs with the same area and material and different shapes were produced, and a road driving test was performed by installing a 32Ch rotating LiDAR on the upper part of the vehicle. As a result of comparing the shape of the point cloud and the NPC according to the shape of the road sign, It is expected that a distance of less than 40m is required to recognize the overall shape of a road sign using 32Ch LiDAR, and shapes such as triangles and rectangles are more advantageous than squares in securing the maximum point cloud from a long distance. As a result of the study according to the height of the road sign, At short distances (within 20m), if the height of the sign is raised to more than 2m, it deviates from the vertical viewing angle of the LiDAR and cannot express the complete point cloud shape. However, it showed a negligible effect compared to the near-field height change. These research results are expected to be utilized in the development of road facilities dedicated to LiDAR for the commercialization of autonomous cooperative driving technology.