• Korean journal of applied entomology
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• v.61 no.1
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• pp.77-83
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• 2022

This study was conducted to determine the optimal composition of sex attractant for monitoring adults of the tobacco cutworm, Spodoptera litura, in Korea. Lures of different compositions from the two sex pheromone components the female, (Z,E)-9,11-tetradecadienyl acetate (Z9E11-14:Ac) and (Z,E)-9,12-tetradecadienyl acetate (Z9E12-14:Ac), were compared for male attraction using synthetic chemicals, rubber septa, and funnel traps in soybean and peanut fields. After sequential tests were conducted using three sets of the two components different ranges from 5:5 to 10:1, from 9:1 to 99:1, and from 9:1 to 39:1, the 19:1 ratio was identified as the most efficient composition. However, S. litura males were barely caught in the trap of the Z9E11-14Ac single component lure. The results show that both the sex attractant compounds are necessary for monitoring adults S. litura males. The higher the pheromone amount in the dispenser in the range from 0.1 to 10 mg, the more males were attracted. Furthermore, the trap height of 1.5 m was optimal for male capture.

• Clinical and Experimental Pediatrics
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• v.64 no.12
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• pp.632-641
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• 2021

Background: Over the past few decades, various goals have been defined to reduce the mortality of children caused by acute lower respiratory infections (ALRIs) worldwide. However, few spatial studies to date have reported on ALRI deaths. Purpose: We aimed to assess the spatial modeling of mortality from ALRI in children under 5 years of age during 2000-2017 using a global data. Methods: The data on the mortality of children under 5 years old caused by ALRI were initially obtained from the official website of the World Health Organization. The income status of their home countries was also gathered from the Country Income Groups (World Bank Classification) website and divided into 5 categories. After that, in the ArcGIS 10.6 environment, a database was created and the statistical tests and related maps were extracted. The Global Moran's I statistic, Getis-Ord Gi statistic, and geographically weighted regression were used for the analyses. In this study, higher z scores indicated the hot spots, while lower z scores indicated the cold spots. Results: In 2000-2017, child mortality showed a downward trend from 17.6 per 100,000 children to 8.1 and had a clustered pattern. Hot spots were concentrated in Asia in 2000 but shifted toward African countries by 2017. A cold spot that formed in Europe in 2007 showed an ascending trend by 2017. Based on the results of geographically weighted regression test, the regions identified as the hot spots of mortality from ALRI in children under 5 years old were among the middle-income countries (R²=0.01, adjusted R²=8.77). Conclusion: While the total number of child deaths in 2000-2017 has decreased, the number of hot spots has increased among countries. This study also concluded that, during the study period, Central and Western Africa countries became the main new hot spots of deaths from ALRI.

• Journal of Industrial Convergence
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• v.21 no.1
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• pp.67-76
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• 2023

COVID-19, which occurred in 2019, has a strong contagious power, has serious symptoms of infection and after-effects, and death in severe cases depending on the underlying disease and symptoms. As COVID-19 is highly contagious, in Korea, screening clinics have been set up across the country to determine whether or not to be positive for COVID-19 and isolate the infected to prevent the spread of COVID-19. However, there are cases where COVID-19 test applicants flock to screening clinics and cannot receive tests due to longer waiting times, and there is a risk that secondary infections may occur in the atmosphere. In this study, the reservation and notification system can be applied from the existing screening care system to solve spatial constraints, reducing waiting time with screening appointments, and solving population bottlenecks to screening clinics. Taking the COVID-19 pandemic as an experience, we propose a system that can present directions in future pandemic situations. To process real-time data, we use Google's Firebase to use Realtime Database in the cloud environment. Because a real-time database is used, users can check the status of screening clinics in real time through the app, make reservations, and receive notifications about test reservations.

• Journal of dental hygiene science
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• v.22 no.4
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• pp.222-232
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• 2022

Background: Self-leadership, an action strategy that can maximize individual capabilities, can affect the organizational commitment of dental hygienists and ultimately improve the quality of medical services. This study aims to demonstrate the need for self-leadership and organizational commitment for dental hygienists and develop measures to improve the quality of medical services. Methods: An online survey of dental hygienists working at dental hospitals and clinics in Seoul and Gyeonggi province, Republic of Korea was conducted from March 28 to May 1, 2022. A total of 341 questionnaires were returned and analyzed. The measurement tools were modified and supplemented based on the theories and models developed by Manz for self-leadership, Mowday for organizational commitment, and Cronin and Taylor for medical services. Descriptive statistics, independent t-tests, ANOVA, simple regression, and multiple regression analyses were performed using SPSS 25.0. Results: In leadership education, self-leadership is based on participation experience, the number of participants, and when and where it is received. Organizational commitment comes from participation experience, and the quality of medical services has been found to affect participation experience and location. Self-leadership had an effect on the quality of medical services (β=0.497, t=10.551, p<0.001; β=0.599, t=13.783, p<0.001; β=0.353, t=7.601, p<0.001) and organizational commitment was found to have a mediating effect. Conclusion: Dental hygienists' self-leadership has a positive effect on the quality of medical services through the formation of appropriate interrelationships within the organization. Therefore, self-leadership programs should be developed, participated in, and promoted to improve the self-leadership of dental hygienists. Moreover, hospitals should improve their environment to provide and improve self-leadership education.

• Composites Research
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• v.36 no.4
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• pp.246-252
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• 2023

A secondary barrier made of glass fiber reinforced composites has been installed infinitely using automatic bonding machine(ABM) in membrane type LNG cargo containment system (CCS). At the same time, significant thermal stress due to cryogenic heat shrinkage has occurred in the composite on the non-bonding area between the adhesive fixation at both ends. There have been studies from the perspective of structural safety evaluation taking this into account, but none that have analyzed mechanical property taking an prolonged length into account. In this study, 2-parameter Weibull distribution statistical analysis was used to standardize reliable mechanical property for actual length, taking into account the composite's brittle fracture of ceramic material with wide fracture strength dispersion. Related experimental data were obtained by performing uniaxial tensile tests at specific temperatures below cryogenic condition considering LNG environment. As a result, the mechanical strength increased about 1.5 times compared to -20℃ at -70℃ and initial non-linear behavior of fiber stretched was suppressed. As the temperature decreased until the cryogenic, the mechanical strength continued to increase due to cold brittleness. The suggested mechanical property in this study would be employed to secure reliable analysis support material property when assessing the safety of secondary barrier's structures.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.1
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• pp.89-96
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• 2023

In this paper, a ferrosilicon by-product was evaluated to confirm the feasibility of recycling it as supplementary cementitious material of ordinary Portland cement in concrete. Three different levels of replacement ratio (10 %, 20 % and 30 % of total binder) were applied to find which is the most beneficial to be used as a binder. Ferrosilicon concrete was initially assessed at setting time and compressive strength. Durability was evaluated by the resistance to chloride penetration test(RCPT) and alkali-silica reaction(ASR) with a comparison to silica fume concrete due to their similarity in chemical composition. The porosimetry and X-ray diffraction analysis along with energy dispersive X-ray spectroscopy give information on the microstructural characteristics of the ferrosilicon concrete. It was found that 10 % ferrosilicon concrete has higher strength while 20 %, 30 % have lower strength than OPC concrete. However, chemical resistance to chloride attack is higher when replacement is increased. Compared to silica fume, the durability of ferrosilicon might be less efficient however, it is obviously beneficial than OPC. High SiO₂ content in ferrosilicon results in producing more C-S-H gel which could make denser pore structure. Most of the risk of alkali silica reaction to silicate binders through length change tests was less than 0.2 %, and both mortar using ferrosilicon and silica fume showed better resistance to alkali silica reaction as the substitution rate increased.Reuse of industrial waste rather than producing highly refined additives might reduce environmental load during manufacture and save costs.

• Journal of Veterinary Science
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• v.24 no.3
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• pp.44.1-44.17
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• 2023

Background: Antibiotic resistance is a significant public health concern around the globe. Antimicrobial peptides exhibit broad-spectrum and efficient antibacterial activity with an added advantage of low drug resistance. The higher water content and 3D network structure of the hydrogels are beneficial for maintaining antimicrobial peptide activity and help to prevent degradation. The antimicrobial peptide released from hydrogels also hasten the local wound healing by promoting epithelial tissue regeneration and granulation tissue formation. Objective: This study aimed at developing sodium alginate based hydrogel loaded with a novel antimicrobial peptide Chol-37(F34-R) and to investigate the characteristics in vitro and in vivo as an alternative antibacterial wound dressing to treat infectious wounds. Methods: Hydrogels were developed and optimized by varying the concentrations of crosslinkers and subjected to various characterization tests like cross-sectional morphology, swelling index, percent water contents, water retention ratio, drug release and antibacterial activity in vitro, and Pseudomonas aeruginosa infected wound mice model in vivo. Results: The results indicated that the hydrogel C proved superior in terms of cross-sectional morphology having uniformly sized interconnected pores, a good swelling index, with the capacity to retain a higher quantity of water. Furthermore, the optimized hydrogel has been found to exert a significant antimicrobial activity against bacteria and was also found to prevent bacterial infiltration into the wound site due to forming an impermeable barrier between the wound bed and external environment. The optimized hydrogel was found to significantly hasten skin regeneration in animal models when compared to other treatments in addition to strong inhibitory effect on the release of pro-inflammatory cytokines (interleukin-1β and tumor necrosis factor-α). Conclusions: Our results suggest that sodium alginate -based hydrogels loaded with Chol-37(F34-R) hold the potential to be used as an alternative to conventional antibiotics in treating infectious skin wounds.

• Journal of the Korean Geotechnical Society
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• v.23 no.1
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• pp.39-49
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• 2007

In this study, quantitative sensitivity analysis on rockfill material influencing the dam crest settlement of CFRD (Concrete-Faced Rockfill Dam) subjected to earthquake loading was carried out. The purpose of this study is to indicate the most important input parameter from the results of sensitivity analysis, to show the quantitative variation of settlement at the crest of CFR type dam during earthquake with this input parameter, and to recommend the approximate estimation method of the settlement on the crest of CFRD subjected to earthquake loading. The statistic characteristics of rockfill parameters which were obtained from large triaxial tests were evaluated. The total 108 dynamic numerical analyses (2 input earthquake, 2 magnitudes for each earthquake, 27 rockfill material property combinations) on CFRD were conducted. The global sensitivity analysis was carried out using the results of numerical analysis. From the sensitivity analysis, It was found that the crest settlement of the CFRD subjected to earthquake was absolutely affected by the shear modulus of rockfill material irrespective of the input earthquakes and the magnitude of input acceleration. On the contrary, it was found that the effect of cohesion and friction angle of rockfill was negligible. From the results of sensitivity analysis and numerical analysis, the approximate estimation method of the settlement on the crest of CFRD subjected to earthquake loading was recommended on condition that the rockfill shear modulus and simple dam information was known.

• Health Policy and Management
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• v.33 no.2
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• pp.141-156
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• 2023

Background: As the population rapidly ages, older adults are increasingly likely to experience mobility problems. This study aims to explore the characteristics related to an elderly person's willingness to live in a nursing home if they have mobility problems Methods: This study analyzed data from 9,917 older adults (5,976 young-old and 3,941 old-old) obtained from the 2020 National Survey of Older Koreans. The dependent variable was the intended place of residence for older adults with mobility problems. Independent variables included various characteristics: (1) sociodemographic and social support, (2) health and functional status, and (3) residential environment. Rao-Scott chi-square tests and survey logistic regression analyses were performed for the young-old and old-old, respectively. Results: The intention to live in a nursing home was significantly different between the young-old (30.4%) and the old-old (34.7%) (p=0.009). According to fully adjusted multivariable analyses, for the young-old, the odds ratio of intending to live in a nursing home was significantly higher in social security benefit recipients (1.45; 95% confidence interval [CI], 1.06-1.97) compared to other individuals. The odds ratio was higher in unmarried (divorced, separated, widowed, or never-married) individuals for both young-old (1.41; 95% CI, 1.22-1.63) and old-old (1.34; 95% CI, 1.09-1.65) age groups, compared to their respective married counterparts. Conclusion: The results of this study suggest that in an aging society, health and social policies should be designed considering the different characteristics of the elderly to improve their health, function, and quality of life.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.3
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• pp.160-174
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• 2023

LiDAR plays a key role in autonomous vehicles, and to improve its visibility, it is necessary to improve its performance and the detection objects. Accordingly, this study proposes a shape for traffic safety signs that is advantageous for self-driving vehicles to recognize. Improvement plans are also proposed using a shape-recognition algorithm based on point cloud data collected through LiDAR sensors. For the experiment, a DBSCAN-based road-sign recognition and classification algorithm, which is commonly used in point cloud research, was developed, and a 32ch LiDAR was used in an actual road environment to conduct recognition performance tests for 5 types of road signs. As a result of the study, it was possible to detect a smaller number of point clouds with a regular triangle or rectangular shape that has vertical asymmetry than a square or circle. The results showed a high classification accuracy of 83% or more. In addition, when the size of the square mark was enlarged by 1.5 times, it was possible to classify it as a square despite an increase in the measurement distance. These results are expected to be used to improve dedicated roads and traffic safety facilities for sensors in the future autonomous driving era and to develop new facilities.