• Journal of Environmental Health Sciences
• /
• v.49 no.2
• /
• pp.89-98
• /
• 2023

Background: Organophosphorus flame retardants (OPFRs) are a group of chemical substances used in building materials and plastic products to suppress or mitigate the combustion of materials. Although OPFRs are generally used in mixed form, information on their mixture toxicity is quite scarce. Objectives: This study aims to elucidate the toxicity and determine the types of interaction (e.g., synergistic, additive, and antagonistic effect) of OPFRs mixtures. Methods: Nine organophosphorus flame retardants, including TEHP (tris(2-ethylhexyl) phosphate) and TDCPP (tris(1,3-dichloro-2-propyl) phosphate), were selected based on indoor dust measurement data in South Korea. Nine OPFRs were exposed to the luminescent bacteria Aliivibrio fischeri for 30 minutes and the human hepatocyte cell line HepG2 for 48 hours. Chemicals with significant toxicity were only used for mixture toxicity tests in HepG2. In addition, the observed EC_x values were compared with the predicted toxicity values in the CA (concentration addition) prediction model, and the MDR (model deviation ratio) was calculated to determine the type of interaction. Results: Only four chemicals showed significant toxicity in the luminescent bacteria assays. However, EC₅₀ values were derived for seven out of nine OPFRs in the HepG2 assays. In the HepG2 assays, the highest to lowest EC₅₀ were in the order of the molecular weight of the target chemicals. In the further mixture tests, most binary mixtures show additive interactions except for the two combinations that have TPhP (triphenyl phosphate), i.e., TPhP and TDCPP, and TPhP and TBOEP (tris(2-butoxyethyl) phosphate). Conclusions: Our data shows OPFR mixtures usually have additivity; however, more research is needed to find out the reason for the synergistic effect of TPhP. Also, the mixture experimental dataset can be used as a training and validation set for developing the mixture toxicity prediction model as a further step.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.23 no.2
• /
• pp.101-110
• /
• 2023

Background: Dentists make various efforts to reduce patients' anxiety and fear associated with dental treatment. Dental sedation is an advanced method that dentists can perform to reduce patients' anxiety and fear and provide effective dental treatment. However, dental sedation is different from general dental treatment and requires separate learning, and if done incorrectly, can lead to serious complications. Therefore, sedation is performed by a limited number of dentists who have received specific training. This study aimed to investigate the proportion of dentists who practice sedation and the main sedatives they use in the context of the Republic of Korea. Methods: We used the customized health information data provided by the Korean National Health Insurance. We investigated the number of dental hospitals or clinics that claimed insurance for eight main sedatives commonly used in dental sedation from January, 2007 to September, 2019 at the Health Insurance Review and Assessment Service. We also identified the changes in the number of dental medical institutions by region and year and analyzed the number and proportion of dental medical institutions prescribing each sedative. Results: In 2007, 302 dental hospitals prescribed sedatives, and the number increased to 613 in 2019. In 2007, approximately 2.18% of the total 13,796 dental institutions prescribed sedatives, increasing to 3.31% in 2019. In 2007, 168 institutions (55.6%) prescribed N₂O alone, and in 2019, 510 institutions (83.1%) made claims for it. In 2007, 76 (25.1%) hospitals made claims for chloral hydrate, but the number gradually decreased, with only 29 hospitals (4.7%) prescribing it in 2019. Hospitals that prescribed a combination of N₂O, chloral hydrate, and hydroxyzine increased from 27 (8.9%) in 2007 to 51 (9%) in 2017 but decreased to 38 (6.1%) in 2019. The use of a combination of N₂O and midazolam increased from 20 hospitals (6.6%) in 2007 to 51 hospitals (8.3%) in 2019. Conclusion: While there is a critical limitation to the investigation of dental hospitals performing sedation using insurance claims data, namely exclusion of dental clinics providing non-insured treatments, we found that in 2019, approximately 3.31% of the dental clinics were practicing sedation and that N₂O was the most commonly prescribed sedative.

• Korean Journal of Clinical Pharmacy
• /
• v.32 no.1
• /
• pp.20-26
• /
• 2022

Background and objective: The Seoul National University Bundang Hospital (SNUBH) implemented ward-based clinical pharmacy system with designated pharmacists in 10 general wards. Designated pharmacists conduct inpatient medication review, medication intervention, and medication consultation, and provide drug information for health care providers. This study aimed to evaluate the clinical pharmacy services and to examine the perception and expectations of health care providers on the services provided by the designated pharmacists in general wards. Methods: A survey was constructed to include questions on the health care providers' recognition, satisfaction, and perceived needs of designated pharmacists. We determined the frequency and type of interventions of ward pharmacist and their acceptance rate through a retrospective observational study using electronic medical records. Results: A total of 59 health care providers responded the questionnaire and 79.7% of the respondents reported moderate to high levels of satisfaction. Satisfaction with the services was positively associated with clinical interventions and nutrition support team (81.4%). Of 59 respondents, 88.1% agreed that preventing drug-related problems by designated pharmacists' activities were effective. The most common interventions included inadequate dosage (27.4%), omission and additional prescription (14.6%) and inadequate drug form (9.6%). The acceptance rate of intervention was 91.5%, and 151 potentially serious risks and 523 significant risks were prevented by the intervention. Conclusion: Positive results were confirmed in the awareness, satisfaction, and perceived needs of the health care providers for designated pharmacists. Expansion of the ward-based clinical pharmacy system with designated pharmacists to other wards may be considered.

• Journal of Digital Convergence
• /
• v.20 no.1
• /
• pp.213-220
• /
• 2022

The purpose of this study is to investigate the relationship between the characteristics of using new words, ability to use new words, and peer popularity among students with mild intellectual disabilities and general students of the age-matched group. A total of 8 students, 4 students with mild intellectual disabilities aged 14 to 16 years of age and 4 normal students in the age-matched group, were compared between groups using a nonparametric test. In the case of new words, 60 new words were selected through expert content validity among 301 new words, and then recognition and background information on the 60 new words were collected. As a result of the study, first, there was a significant difference in understanding of new words between the student group with mild intellectual disability and the general student group of the same age. Second, the correlation between the use of new words and the popularity of peers was compared for each group of students with mild intellectual disabilities and a group of general students of the same age as possible. Therefore, when providing vocabulary instruction for students with mild intellectual disabilities, it suggests that it is necessary to teach new vocabulary in order to increase their relationship with their peers and their popularity.

• Korean small business review
• /
• v.41 no.1
• /
• pp.75-96
• /
• 2019

This study used age, education, major, working period as CEO's characteristics and examine relationship between these characteristics and R&D Investment. Furthermore this study examined how CEO should react in terms of R&D investment, which is effected by CEO's characteristic in the market. The empirical results are following. (1) When CEO's age are young, they spend much money for R&D investment. And R&D investment which is determined by young CEO has a positive effect on relation of firm value. (2) A higher educational background has a positive effect on R&D investment and will create higher firm value. (3) When CEO's major is competitive in the same industry, it has a positive relationship with R&D investment and its firm value is bigger than though. (4) When CEO working period is long, they showed active to R&D investment. On the other hand, the firm value decreased. This study focused on analyzing the relationship between characteristics of CEO and R&D Investment, furthermore, how R&D investment which effected by CEO's characteristic is contributing in creating the firm value. This results indicate that CEO's characteristics reflect R&D investment and value of venture business. Therefore, CEO's characteristics should be considered financial information and firm value in the market.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.6 no.3
• /
• pp.19-31
• /
• 2016

Game Trailer plays the role of main marketing for promotion of game. Recently, the characteristic can be summarized as storytelling, graphics method, production technology, and game mechanics of 3D Game Trailer. Online game was produced as cinematic trailer in the beginning, but recently, in-game trailer has been produced as machinima production method for users. This method reveals functions, various contents, and graphics related to the game through trailer, and it is useful in giving information and curiosity related to the game. Machinima composes background and characters in a short period of time online due to recent 3D CG methods, and only dubbing needs to be proceeded. This saves production fee and production period, and it also has the advantage of having multi-story. Game trailer Thanatos is a video developed through machinima production method. This paper proposes production process and the importance of the key components of the whole project through the above four aspects to be used in the actual production stage by intuitively apply and analysis.

• Korean Journal of Environmental Agriculture
• /
• v.41 no.4
• /
• pp.282-287
• /
• 2022

BACKGROUND: Green algae (Chlorella spp.) has been widely used as a biofertilizer to improve the crop yield and quality. However, available information is not enough to verify the mechanism of green algae's beneficial impact on strawberry. This study was conducted to investigate the effect of Chlorella fusca CHK005 application on the growth and nutrient status of strawberry plant and fruit characteristics. METHODS AND RESULTS: A total of 800 seedlings of strawberry variety 'Kuemsil' were planted. Once a week, C. fusca culture solution (1.0 × 10⁷ cells mL^-1) was applied into soil via irrigation in four different concentrations: no application (control), 1/1000 times (× 0.5), 1/500 times (× 1), and 1/250 times (× 2). Result showed that growth of strawberry plant was enhanced by Chlorella application and the highest impact on fresh weight (FW) and chlorophyll content of the plants were observed in × 2 treatment, followed by × 1, × 0.5, and control treatments. The phosphorus (P) concentration in the plant was significantly higher in × 1 and × 2 treatments compared to control. In case of fruit quality, sugar content (°Brix), hardness, and FW were lowest in control, but these values increased as application levels of Chlorella were higher. Also, P and K contents in the fruits increased with increasing the application levels and significant correlation between P content and oBrix in the fruits was found. CONCLUSION(S): Overall, Chlorella application seemed to improve plant growth and fruit quality by increasing the utilization efficiency of P and K in strawberries.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.3
• /
• pp.825-834
• /
• 2023

The demands of people who purchase fashion products on Internet shopping are gradually increasing, and attempts are being made to provide user-friendly images with 3D contents and web 3D software instead of pictures and videos of products provided. As a reason for this issue, which has emerged as the most important aspect in the fashion web shopping industry, complaints that the product is different when the product is received and the image at the time of purchase has been heightened. As a way to solve this problem, various image processing technologies have been introduced, but there is a limit to the quality of 2D images. In this study, we proposed an automatic conversion technology that converts 2D images into 3D and grafts them to web 3D technology that allows customers to identify products in various locations and reduces the cost and calculation time required for conversion. We developed a system that shoots a mannequin by placing it on a rotating turntable using only 8 cameras. In order to extract only the clothing part from the image taken by this system, markers are removed using U-net, and an algorithm that extracts only the clothing area by identifying the color feature information of the background area and mannequin area is proposed. Using this algorithm, the time taken to extract only the clothes area after taking an image is 2.25 seconds per image, and it takes a total of 144 seconds (2 minutes and 4 seconds) when taking 64 images of one piece of clothing. It can extract 3D objects with very good performance compared to the system.

• KIPS Transactions on Software and Data Engineering
• /
• v.12 no.5
• /
• pp.217-228
• /
• 2023

Video instance segmentation is an intelligent visual task with high complexity because it not only requires object instance segmentation for each image frame constituting a video, but also requires accurate tracking of instances throughout the frame sequence of the video. In special, human instance segmentation in drama videos has an unique characteristic that requires accurate tracking of several main characters interacting in various places and times. Also, it is also characterized by a kind of the class imbalance problem because there is a significant difference between the frequency of main characters and that of supporting or auxiliary characters in drama videos. In this paper, we introduce a new human instance datatset called MHIS, which is built upon drama videos, Miseang, and then propose a novel video data augmentation method, CDVA, in order to overcome the data imbalance problem between character classes. Different from the previous video data augmentation methods, the proposed CDVA generates more realistic augmented videos by deciding the optimal location within the background clip for a target human instance to be inserted with taking rich spatio-temporal context embedded in videos into account. Therefore, the proposed augmentation method, CDVA, can improve the performance of a deep neural network model for video instance segmentation. Conducting both quantitative and qualitative experiments using the MHIS dataset, we prove the usefulness and effectiveness of the proposed video data augmentation method.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.29 no.7
• /
• pp.910-914
• /
• 2023

With the technological innovation owing to the 4th industrial revolution, the maritime transportation is rapidly being developed with autonomous ships and systems. Particularly, autonomous ships will partially replace the manned ships and navigation among them remotely upon the degree of autonomy suggested by IMO. Accordingly, the remote operator and related research have increased as well. However, the data on the minimum required manpower for remote operators are lacking such as considering engage required situations and their co-occurrence probability. Therefore, this study proposes a simulation model that calculates the number of remote engage required situations by defining restricted water area and remote engage required situation as close-quarter situations based on accumulated trajectory data of actual ships. The findings are expected to be used as background materials to establish the appropriate manpower distribution of remote operators in remote operation centers.