• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.547-552
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• 2022

In this study, we secured a technology for manufacturing expanded glass of uniform quality by using general tempered glass, that is, window glass, among automotive glass that is scrapped, and verified whether the manufactured expanded glass can be used for lithium battery fire suppression. The process of manufacturing expanded glass using waste glass is generally divided into Crushing → Milling → Granulation → Expansion → Cooling. With several trials a nd errors. It is obtained a yield of 0.5 ø mm to 2 ø mm spherical particles of 80 % or more. By comparing the surface analysis and physical properties, a more suitable sample was selected as a fire extinguishing agent for lithium batteries, and it was confirmed that the result of the adaptability test for lithium battery fire was satisfactory.

• Journal of the Korean Electrochemical Society
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• v.25 no.1
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• pp.32-41
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• 2022

Various steps in the electrode production process, such as slurry mixing, slurry coating, drying, and calendaring, directly affect the quality and, consequently, mechanical properties and electrochemical performance of electrodes. Herein, a new method of slurry coating is developed: Double-coated electrode. Contrary to single-coated electrode, the cathode is prepared by double coating, wherein each coat is of half the total loading mass of the single-coated electrode. Each coat is dried and calendared. It is found that the double-coated electrode possesses more uniform pore distribution and higher electrode density and allows lesser extent of particle segregation than the single-coated electrode. Consequently, the double-coated electrode exhibits higher adhesion strength (74.7 N m^-1) than the single-coated electrode (57.8 N m^-1). Moreover, the double-coated electrode exhibits lower electric resistance (0.152 Ω cm^-2) than the single-coated electrode (0.177 Ω cm^-2). Compared to the single-coated electrode, the double-coated electrode displays higher electrochemical performance by exhibiting better rate capability, especially at higher C rates, and higher long-term cycling performance. Despite its simplicity, the proposed method allows effective electrode preparation by facilitating high electrochemical performance and is applicable for the large-scale production of high-energy-density electrodes.

• Korean Journal of Agricultural Science
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• v.48 no.4
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• pp.945-956
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• 2021

The effective growth of pepper seedlings relies on the growing period and tray used, which both aim to minimize seedling damage during the transplantation process. Therefore, the objective of this study was to evaluate the effect of red and green pepper seedling growth in plug and cylindrical paper pot (CPP) trays with different growth periods of the seedlings. Two different seedling growth trays were used for the two varieties of pepper seedlings in the same growing media. The pepper seedling growth rates were investigated at 15, 30, and 45 days for each of variety. Important parameters, e.g., the plant height, fresh weight for the plant and root, number of leaves, leaf length and width, and leaf chlorophyll contents, were measured. During the experiment, the CPP tray maintained uniform seedling growth as compared to the plug tray. CPP trays ensured the height of the seedling, with these results 0.84 to 1.6 times higher than those of the plug tray for all conditions, indicating the good quality of the pepper seedlings. The shoot and root weights were found to be greater with more leaves in the CPP tray seedlings for 45 days compared to the seedlings grown in the plug tray, whereas the green pepper variety showed a greater leaf ratio than the red pepper seedlings. The analysis of pepper seedling growth presented in this study will guide the selection of suitable growth trays and seedling periods for farmers when they undertake automatic pepper transplantation in the field.

• Journal of Aerospace System Engineering
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• v.16 no.1
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• pp.12-16
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• 2022

Currently, Induction welding is attracting attention as a non-contact, clean and fast welding process. However, since thermoplastic resins are not affected by electromagnetic fields, induction welding requires a heating element called a susceptor. Researches are being conducted with the aim of achieving high-quality bonding, however, the factor of a heating element is an issue, hence the need to set a standard. Specimen fabrication and testing are conducted according to ASTM D5868. In this study, we propose that the evaluation criteria be judged on the basis of three factors; the condition of the welded joint surface, void content, and lap shear strength. Since the adhesive surface to be welded melts and solidifies as it cools, rapid temperature changes can generate pores. In addition, if the heating is not uniform, it is difficult to expect the desire performance. Using PA6 (CF 30%) thermoplastic, susceptor fabrication, induction welding and performance verification were conducted.

• Korean Journal of Remote Sensing
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• v.39 no.5_4
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• pp.1145-1153
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• 2023

Urban trees play an important role in absorbing carbon dioxide from the atmosphere, improving air quality, mitigating the urban heat island effect, and providing ecosystem services. To effectively manage and conserve urban trees, accurate spatial information on their location, condition, species, and population is needed. In this study, we propose an algorithm that uses a high-resolution urban tree cover map constructed from deep learning approach to separate trees from the urban land surface and accurately detect tree locations through local maximum filtering. Instead of using a uniform filter size, we improved the tree detection performance by selecting the appropriate filter size according to the tree height in consideration of various urban growth environments. The research output, the location and height of individual trees in human settlement over Suwon, will serve as a basis for sustainable management of urban ecosystems and carbon reduction measures.

• Journal of Korean Critical Care Nursing
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• v.16 no.3
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• pp.1-10
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• 2023

Purpose : This study explores the professional status of Advanced Practice Nurses (APNs) in Korea, who, despite being legally certified, face instability in their professional standing, including their scope of practice and compensation. Method : The study uses Flexner's professional characteristics as a framework to analyze and project the future trajectory of Korean APNs. Results : First, to ensure social accountability, professional bodies need to establish uniform nursing policies related to job roles, and healthcare institutions must adhere to these policies. Second, nursing leaders should spearhead the creation of nursing knowledge essential for the profession's advancement, aiming to establish it as the foundation for nursing practice through a consensus process within the nursing community. Third, the curriculum for APNs should enhance the quantitative and qualitative aspects of practice in response to societal needs. Fourth, professional bodies should formulate consistent nursing policies based on a thorough analysis of the healthcare environment and legal considerations, and guide their implementation in clinical practice through a consensus process within the nursing community. Lastly, guidelines should be established for professional standards suitable for the Korean context. Conclusion : Based on this review, it is recommended that all APNs adhere to the professional standards set by their respective organizations, actively participate in personal quality improvement initiatives, and fulfill their duties and roles as members of these professional bodies. Furthermore, these organizations should devise practical strategies to solidify the APN system and should spearhead a systematic consensus process that garners the agreement of all members within the nursing community.

• Animal Bioscience
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• v.37 no.5
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• pp.817-825
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• 2024

Objective: The aim of this study was to identify suitable polynomial regression for modeling the average growth trajectory and to estimate the relative development of the rib eye area, scrotal circumference, and morphometric measurements of Guzerat young bulls. Methods: A total of 45 recently weaned males, aged 325.8±28.0 days and weighing 219.9±38.05 kg, were evaluated. The animals were kept on Brachiaria brizantha pastures, received multiple supplementations, and were managed under uniform conditions for 294 days, with evaluations conducted every 56 days. The average growth trajectory was adjusted using ordinary polynomials, Legendre polynomials, and quadratic B-splines. The coefficient of determination, mean absolute deviation, mean square error, the value of the restricted likelihood function, Akaike information criteria, and consistent Akaike information criteria were applied to assess the quality of the fits. For the study of allometric growth, the power model was applied. Results: Ordinary polynomial and Legendre polynomial models of the fifth order provided the best fits. B-splines yielded the best fits in comparing models with the same number of parameters. Based on the restricted likelihood function, Akaike's information criterion, and consistent Akaike's information criterion, the B-splines model with six intervals described the growth trajectory of evaluated animals more smoothly and consistently. In the study of allometric growth, the evaluated traits exhibited negative heterogeneity (b<1) relative to the animals' weight (p<0.01), indicating the precocity of Guzerat cattle for weight gain on pasture. Conclusion: Complementary studies of growth trajectory and allometry can help identify when an animal's weight changes and thus assist in decision-making regarding management practices, nutritional requirements, and genetic selection strategies to optimize growth and animal performance.

• The korean journal of orthodontics
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• v.54 no.1
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• pp.26-47
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• 2024

Objective: This systematic review aimed to evaluate the correlation between vitamin D levels and the rate of tooth movement, external apical root resorption, bone biomarker expression, and bone remodeling. Methods: Three databases (PubMed, Scopus, and Web of Science) were systematically searched from inception until 14th March 2023 to identify studies investigating the correlation between orthodontic tooth movement and vitamin D in animals and humans. The quality assessment was made in accordance with the Joanna Briggs Institute Critical Appraisal Checklist. Results: Overall, 519 records were identified, and 19 were selected for the qualitative synthesis. Eleven studies investigated the effect of local administration (injections in the periodontal ligament, to the gingiva distal to the teeth, or submucosae palatal area) and systemic administration (oral supplementation) of vitamin D on tooth movement, external apical root movement, pro-inflammatory cytokines, and bone remodeling factors. The remaining eight studies investigated the correlation between serum vitamin D levels and salivary vitamin D levels on bone turnover markers and tooth movement. Conclusions: The findings of this systematic review support that vitamin D3 local injections might increase the rate of tooth movement via the receptor activator of the nuclear factor-kB/osteoprotegerin axis. However, the non-uniform study designs and the different protocols and outcome methods make it challenging to draw reliable conclusions.

• Food Science of Animal Resources
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• v.44 no.3
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• pp.723-737
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• 2024

Yeast protein can be a nutritionally suitable auxiliary protein source in livestock food. The breakdown of proteins and thereby generating high-quality peptide, typically provides nutritional benefits. Enzyme hydrolysis has been effectively uesed to generate peptides; however, studies on the potential applications of different types of enzymes to produce yeast protein hydrolysates remain limited. This study investigated the effects of endo- (alcalase and neutrase) and exotype (flavourzyme and prozyme 2000P) enzyme treatments on yeast protein. Endotype enzymes facilitate a higher hydrolysis efficiency in yeast proteins than exotype enzymes. The highest degree of hydrolysis was observed for the protein treated with neutrase, which was followed by alcalase, prozyme 2000P, and flavourzyme. Furthermore, endotype enzyme treated proteins exhibited higher solubility than their exotype counterparts. Notably, the more uniform particle size distribution was observed in endotype treated yeast protein. Moreover, compared with the original yeast protein, the enzymatic protein hydrolysates possessed a higher content of β-sheets structures, indicating their higher structural stability. Regardless of enzyme type, enzyme treated protein possessed a higher total free amino acid content including essential amino acids. Therefore, this study provides significant insights into the production of protein hydrolysates as an alternative protein material.

• Journal of the Institute of Convergence Signal Processing
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• v.24 no.4
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• pp.249-254
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• 2023

Recently, the distribution of drones is being activated by saving farmers' working time and protecting them from harmful human bodies from pesticides due to the mission of spraying pesticides using drones. It is possible to compensate for various shortcomings derived from the existing pesticide spraying method, wide-area control and helicopter control. Recently, the smart farm expansion policy has actively used it to generate profits for farmers by increasing harvests by monitoring growth information of various crops based on IoT in real time and collecting big data on key variables, and related drone industry technologies are also being developed. In this study, drones were applied to the work of shading greenhouses to secure diversity in agricultural application fields, and basic research on the greenhouse environment was conducted to materialize the technology related to shading. In order to provide high-quality light in consideration of the internal and external environment of the green house, basic research was conducted to enable light-shielding missions using drones through nozzle design for uniform spraying of nozzles of drones, light-transmitting rate analysis of green houses, and light-shielding agent application experiments.