• Animal Bioscience
• /
• v.35 no.2
• /
• pp.224-235
• /
• 2022

Objective: Cage rearing has critical implications for the laying duck industry because it is convenient for feeding and management. However, caging stress is a type of chronic stress that induces maladaptation. Environmental stress responses have been extensively studied, but no detailed information is available about the comprehensive changes in plasma metabolites at different stages of caging stress in ducks. We designed this experiment to analyze the effects of caging stress on performance parameters and oxidative stress indexes in ducks. Methods: Liquid chromatography tandem mass spectrometry (LC/MS-MS) was used to determine the changes in metabolites in duck plasma at 5 (CR5), 10 (CR10), and 15 (CR15) days after cage rearing and traditional breeding (TB). The associated pathways of differentially altered metabolites were analyzed using Kyoto encyclopedia of genes and genomes (KEGG) database. Results: The results of this study indicate that caging stress decreased performance parameters, and the plasma total superoxide dismutase levels were increased in the CR10 group compared with the other groups. In addition, 1,431 metabolites were detected. Compared with the TB group, 134, 381, and 190 differentially produced metabolites were identified in the CR5, CR10, and CR15 groups, respectively. The results of principal component analysis (PCA) show that the selected components sufficiently distinguish the TB group and CR10 group. KEGG analysis results revealed that the differentially altered metabolites in duck plasma from the CR5 and TB groups were mainly associated with ovarian steroidogenesis, biosynthesis of unsaturated fatty acids, and phenylalanine metabolism. Conclusion: In this study, the production performance, blood indexes, number of metabolites and PCA were compared to determine effect of the caging stress stage on ducks. We inferred from the experimental results that caging-stressed ducks were in the sensitive phase in the first 5 days after caging, caging for approximately 10 days was an important transition phase, and then the duck continually adapted.

• Journal of Korea Entertainment Industry Association
• /
• v.14 no.3
• /
• pp.211-227
• /
• 2020

This study intends to analyze the storytelling strategy of EBS's YouTube channel , which has been creating a remarkable cultural phenomenon since April 2019, and to examine the potential for its transition to transmedia franchise. Based on Henry Jenkins'seven principles of transmedia storytelling, shows satisfactory relevance in all but 'multiplicity'out of the 10 capacities consisting of the principles. In particular, was found excellent in terms of core capacities such as 'spreadability', 'immersion', 'worldbuilding', 'continuity', 'drillability' and 'performance'. In addition, critical discourse analysis(CDA) in sociocultural practice dimension of the keywords of the related news articles has discovered that is strongly linked to the following five values: 'social integration', 'resistance against authoritarianism', 'self-dignity and reasonable individualism', 'gender neutrality' and 'ecologism', indicating the reason why the work has been able to resonate so extraordinarily with participants across all generations. By answering the two chosen research questions, this study has proved that has high potential to be successful in evolving into transmedia franchise, while keeping building a new realm of edutainment storytelling by cleverly exploiting EBS's unique identity as a public education broadcaster. is viewed as an exceptional property capable of advancing transmedia storytelling in the local market; thus, productive arguments and contemplation over its evolution in storytelling needs to continue so that it can maintain a long-lasting positive influence.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.24 no.3
• /
• pp.190-200
• /
• 2022

In this study, the island's land-use and land-cover change (LULCC) is analyzed in South Korea using remotely sensed land cover data(Globeland 30) acquired from 2000 to 2020 to meet the requirement of providing practical information for forest management. Analysis of LULCC between the 2000 and 2020 images revealed that changes to agricultural land were the most common type of change (7.6% of pixels), followed by changes to the forest (5.7%). The islands forests maintain 157,246 ha (42.2% of the total island area). Land cover types that changed to the forest from grasslands were 262 islands, while reverse cases have occurred on 421 islands. These 683 islands have a possibility of transition and disturbance. The artificial land class was newly calculated in 22 islands. The forests, which account for 42.2% of the 22 island area, turned into grassland, and 27.8% of agricultural land and grassland turned into forests. The development of artificial land often affects developed areas and surrounding areas, resulting in deforestation, management of agriculture, and landscaping. This study can provide insights concerning the fundamental data for assessing ecological functions and constructing forest management plans in islands ecosystems.

• Journal of the Korea Institute of Building Construction
• /
• v.22 no.6
• /
• pp.543-551
• /
• 2022

The mechanical performance and vibration damping ratio performance of a specimen according to the polymer mixing rate were evaluated for polymer modified mortar. As a polymer, Styrene Butadiene Rubber(SBR) liquid polymer with a solid content of about 49~51% was used, and the polymer content was increased by liquid 5%. The specimen was 40*40*160(mm), and after curing, compressive strength, flexural strength, and vibration damping ratio were measured using the ultrasonic pulse method. As a result, it was found that the compressive strength decreased as the polymer was mixed, but the flexural strength was increased. The vibration damping ratio increased by 11% at 5% polymer, 28% at 10% polymer, 33% at 15% polymer, and 72 at 20% polymer. I was found that the incorporation of the polymer was very effective to reduce the vibration of the mortar. In addition, through SEM and SEM-EDS analysis, it is determined that the cause of vibration reduction due to polymer mixing is that the polymer film formed in the transition zone of aggregate and internal voids buffered the vibration of the mortar inside. Taken together, in the scope of this study, the appropriate polymer mixing ratio for reducing the vibration of mortar is judged to be about 7.5%.

• Journal of Korea Entertainment Industry Association
• /
• v.14 no.7
• /
• pp.69-77
• /
• 2020

Korea's golf fever is as good as the United States, Europe and Japan, which are called golf powers. The senior golf population over 55 years old has exceeded 2.5 million, and they are more interested in improving golf performance than participating in golf. So, this study aims to emphasize the importance of dynamic preparation exercise by identifying the effects of dynamic preparation exercise on golf physical strength and golf batting in order to suggest a way to help the elderly men's golf performance. The experimental group(n=13) and the control group(n=14) were divided into two groups and repeated measurements were conducted by two-way ANOVA with pre- and post-design. As a result of the analysis, the flexibility factor showed a positive effect on golf physical strength, and in golf batting, head speed, distance, and attack angle showed interaction effect, which led to the conclusion that dynamic preparation exercise helped the golf performance of the elderly male. Therefore, the continuous dynamic preparation exercise led to positive transition to head speed and attack angle due to the increase in the flexibility of the body, which led to the improvement of distance and the increase in performance level.

• Composites Research
• /
• v.36 no.1
• /
• pp.16-24
• /
• 2023

This paper presents a multi-scale progressive fatigue damage model incorporating the model for interfacial debonding between fibers and matrix. The micromechanics model for the progressive interface debonding was adopted, which defined the four different interface phases: (1) perfectly bonded fibers; (2) mild imperfect interface; (3) severe imperfect interface; and (4) completely debonded fibers. As the number of cycles increases, the progressive transition from the perfectly bonded state to the completely debonded fiber state occurs. Eshelby's tensor for each imperfect state is calculated by the linear spring model for a damaged interface, and effective elastic properties are obtained using the multi-phase homogenization method. The fatigue damage evolution formulas for fiber, matrix and interface were proposed to demonstrate the fatigue behavior of CFRP laminates under cyclic loading. The material parameters for the fiber/matrix fatigue damage were characterized using the chaotic firefly algorithm. The model was implemented into the UMAT subroutine of ABAQUS, and successfully validated with flat-bar UD laminate specimens ([0]₈,[90]₈, [30]₁₆) of AS4/3501-6 graphite/epoxy composite.

• The Mathematical Education
• /
• v.62 no.2
• /
• pp.269-287
• /
• 2023

Matrix theory is widely used not only in mathematics, natural sciences, and engineering, but also in social sciences and artificial intelligence. In the 2009 revised mathematics curriculum, matrices were removed from high school math education to reduce the burden on students, but in anticipation of the age of artificial intelligence, they will be reintegrated into the 2022 revised education curriculum. Therefore, there is a need to analyze the matrix content covered in other countries to suggest a meaningful direction for matrix education and to derive implications for textbook composition. In this study, we analyzed the German mathematics curriculum and standard education curriculum, as well as the matrix units in the German Hesse state mathematics curriculum and textbook, and identified the characteristics of their content elements and development methods. As a result of our analysis, it was found that the German textbooks cover matrices in three categories: matrices for solving linear equations, matrices for explaining linear transformations, and matrices for explaining transition processes. It was also found that the emphasis was on mathematical reasoning and modeling when learning matrices. Based on these findings, we suggest that if matrices are to be reintegrated into school mathematics, the curriculum should focus on deep conceptual understanding, mathematical reasoning, and mathematical modeling in textbook composition.

• Journal of Service Research and Studies
• /
• v.12 no.4
• /
• pp.30-49
• /
• 2022

Recently, as the transition to the untact era due to COVID-19 accelerates, non-face-to-face and non-contact practices have become commonplace, and the OTT (Over-The-Top) service market that provides media content such as movies and broadcast programs through the open Internet is largely expanded and it is receiving great attention from the MZ generation, who are familiar with digital devices and environments. In this study, the effects of OTT service characteristics on MZ generation users' flow, satisfaction and brand loyalty were examined, focusing on Netflix users, one of the representative OTT service brands. In order to carry out this study, a total of 216 people who have used the Netflix OTT service platform were empirically verified by using the survey data of those who have used it for analysis. As a result of the analysis, it was found that among the characteristics of OTT service, contents diversity, convenience, and reliability had a positive (+) effect on flow. Also, flow has a positive (+) effect on satisfaction, and satisfaction has a positive (+) effect on brand loyalty. However, among the characteristics of the OTT service, the recommended service did not have a positive (+) effect on the flow, and the flow did not have a direct positive (+) effect on the brand loyalty. Flow had a positive (+) effect on the brand loyalty through satisfaction. Through this study, it is expected that the market revitalization of the OTT service-related industry and the increasing number of OTT service brands will be able to contribute to the establishment of marketing strategies for the MZ generation consumers, and to provide practical implications.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.43 no.3
• /
• pp.381-395
• /
• 2023

This paper presents a GIS-based site suitability analysis for a smart hydrogen energy plant in the Gangwon-Do region, South Korea. A GIS-based multi-criteria decision analysis (MCDA) was implemented in this study to identify the most suitable sites for the development of smart hydrogen energy plants. The study utilizes various spatial data layers, including hydrogen generation potential and climatic conditions, environmental and topographic conditions, and natural catastrophic conditions, to evaluate the suitability of potential sites for the hydrogen energy plant. The spatial data layers were then used to rank and prioritize the sites based on suitability. The findings revealed that 4.26% of the study area, or 712.14 km², was suitable for constructing smart hydrogen energy plants. Some regions of Cheorwon-gun, Chuncheon-si, Wonju-si, Yanggu-gun, Gangneung-si, Hoengseong-gun, and near the coastal region along the east coast were found to be suitable for solar and wind energy utilization. The proposed MCDA provides a valuable tool for decision-makers and stakeholders to make informed decisions on the location of smart hydrogen energy plants and supports the transition to a sustainable and low-carbon energy system. Decision-makers can use the results of this study to select suitable sites for constructing smart hydrogen energy plants.

• Animal Bioscience
• /
• v.35 no.10
• /
• pp.1512-1523
• /
• 2022

Objective: The growth of pigs involves multiple regulatory mechanisms, and modern molecular breeding techniques can be used to understand the skeletal muscle growth and development to promote the selection process of pigs. This study aims to explore candidate lncRNAs and mRNAs related to skeletal muscle growth and development among Duroc pigs with different average daily gain (ADG). Methods: A total of 8 pigs were selected and divided into two groups: H group (high-ADG) and L group (low-ADG). And followed by whole transcriptome sequencing to identify differentially expressed (DE) lncRNAs and mRNAs. Results: In RNA-seq, 703 DE mRNAs (263 up-regulated and 440 down-regulated) and 74 DE lncRNAs (45 up-regulated and 29 down-regulated) were identified. In addition, 1,418 Transcription factors (TFs) were found. Compared with mRNAs, lncRNAs had fewer exons, shorter transcript length and open reading frame length. DE mRNAs and DE lncRNAs can form 417 lncRNA-mRNA pairs (antisense, cis and trans). DE mRNAs and target genes of lncRNAs were enriched in cellular processes, biological regulation, and regulation of biological processes. In addition, quantitative trait locus (QTL) analysis was used to detect the functions of DE mRNAs and lncRNAs, the most of DE mRNAs and target genes of lncRNAs were enriched in QTLs related to growth traits and skeletal muscle development. In single-nucleotide polymorphism/insertion-deletion (SNP/INDEL) analysis, 1,081,182 SNP and 131,721 INDEL were found, and transition was more than transversion. Over 60% of percentage were skipped exon events among alternative splicing events. Conclusion: The results showed that different ADG among Duroc pigs with the same diet maybe due to the DE mRNAs and DE lncRNAs related to skeletal muscle growth and development.