• The Journal of the Korea Contents Association
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• v.22 no.9
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• pp.570-582
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• 2022

Nucleoplasty is a type of percutaneous disc decompression that has been developed to treat herniated intervertebral discs. Currently, in some clinics, researchers have also applied this procedure to patients with internal disc disruption, apart from the originally intended usage on herniated intervertebral discs. The purpose of this study is to evaluate the feasibility of this extended use based on medical logic. To achieve this, the author analyzed case studies on performing nucleoplasty on patients with internal disc disruption. The main points of the analysis are, first, the validity of the treatment evidence presented by the researchers and, second, the relevance of the patient selection criteria. As a result, it is judged that the therapeutic rationale of existing papers applying nucleoplasty to the treatment of internal disc disruption is unclear or inconsistent with general medical logic, and in the process of patient screening, discs that may be deemed inappropriate for percutaneous decompression are included. Therefore, the author believes that existing studies applying nucleoplasty to the treatment of internal disc disruption have the nature of somewhat adventurous experiments that are unnecessary or can cause potential side effects. In order to uphold patients' rights and improve the completeness of the study in the research process on this topic, the author thinks that it is essential to establish clearer therapeutic evidence than the current level of understanding and to have an elaborate patient screening process based on it.

• Journal of the Korean Orthopaedic Association
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• v.55 no.4
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• pp.331-337
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• 2020

Purpose: The aim of this retrospective study was to define the prognostic factors for liposarcoma to aid in the selection of effective treatments. Materials and Methods: This study analyzed 41 cases out of 45 cases diagnosed with and treated for liposarcoma 2002 to 2015; 4 cases of well-differentiated liposarcoma were excluded. The effects of sex, age, site, stage, and histological classification on survival were analyzed retrospectively. For 28 cases diagnosed with myxoid liposarcoma, additional analysis was performed after the inclusion of round cell components. Results: The mean age at diagnosis was 52.05 years (range 25-82 years) and the average follow-up period was 63.7 months. The disease-free survival rate was 43.2%. Most factors, including sex and age, were not significantly associated with the survival rate. On the other hand, the stage (Musculoskeletal Tumor Society stage) was significantly associated with the survival rate. The survival rate of patients with myxoid liposarcoma was 69% and the local recurrence and metastasis results varied according to the presence of round cells. Conclusion: The stage of liposarcoma and the sex of the patient were found to be effective factors for prognosis. When planning the treatment for liposarcoma, the treatment outcome for liposarcoma differs according to several prognostic factors.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.6
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• pp.231-238
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• 2022

To secure the mechanical strength of porous Al₂O₃ ceramics, which can be utilized for filters and catalyst supports is essential for their functionality and durability. Superior mechanical strength would be obtained by tailoring the densification and grain growth during sintering. This study deals with grain growth behavior of a freeze-casted Al₂O₃ with addition of La₂O₃. In a temperature range between 1400 and 1600℃, variations of average grain size with sintering time and temperature were observed and analyzed with G_tⁿ-G₀ⁿ = kt and with k = k₀exp(-E_a/RT). As a result, n value and activation energy (E_a) for grain growth were calculated as 3 and 489.09 kJ/mol, respectively. These commonly confirms retardation effect of the La addition during sintering of Al₂O₃ porous structure. More accurate analysis on the La effect can be followed to provide useful guidance for the selection of additives for better mechanical strength in Al₂O₃ porous structures.

• Journal of Navigation and Port Research
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• v.46 no.4
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• pp.351-358
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• 2022

This study analyzed changes in the market concentration of Korean ocean-going shipping companies using shipping revenue based CR (Concentration Ratio), and HHI (Herfindahl - Hirschman Index) to examine the effects of the government's selection and concentration based the shipping reconstruction scheme. The results of this study showed that the market structure of the Korean shipping industry has changed from a competitive market to a rather concentrated market, as CR as well as HHI values have increased from 2019 to 2021. In particular, the market share of the deep-sea shipping lines has risen significantly compared to the intra-Asian short-sea shipping lines and the tramp carriers, implying that the Korean liner shipping market has become a monopoly, or highly concentrated oligopoly market. Compared to other shipping markets, the high rise in ocean freight rates (i.e. Asia-Europe America) was the leading cause of the increase in the revenues of the ocean-going shipping lines, and the increased fleet through preemptive government support has enabled them to achieve more revenues. As a result, it can be interpreted that the government's fleet expansion strategy has been more effective than expected, but it is too early to conclude if the market structure of the Korean ocean-going shipping companies has been strengthened.

• Journal of Korea Water Resources Association
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• v.55 no.11
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• pp.979-989
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• 2022

In hydrological surveys, observation through representative location is essential due to temporal and spatial limitations and constraints. Regarding the use of hydrological data and the accuracy of the data, there are still insufficient observatories to be used in a specific watershed. In addition, since there is virtually no standard for the location of the current evapotranspiration, this study proposes a method for determining the location of the evapotranspiration. To determining the location of evapotranspiration, a grid is selected in consideration of the operating range of the Flux Tower using the eddy covariance measurement method, which is mainly used to measure evapotranspiration. The grid of representative location was calculated using the factors affecting evapotranspiration and satellite data of evapotranspiration. The grid of representative location was classified as good, fair, and poor. As a result, the number of good grids calculated was 54. It is judged that the classification of the grid has been achieved regarding topography and land use as a characteristic that appeared in the classification of the grid. In particular, in the case of elevation or city area, there was a large deviation, and the calculated good grid was judged to be a group between the two distributions.

• Journal of Practical Engineering Education
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• v.14 no.2
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• pp.235-244
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• 2022

In this study, a class operation case of an engineering design project targeting a golf ball dispenser, a commercial product, was presented. The project was carried out according to the systematic engineering design approach suggested by Kim Jong-won and W. Beitz. This method broadly divides engineering design into four stages: 'product planning → conceptual design → basic design → detailed design'. In particular, the conceptual design stage is divided into 'functional structure diagram → detailed working principle exploration → various design alternatives creation → optimal design selection'. In the conceptual design, the input/output of the golf ball dispenser was defined and a functional structure diagram was prepared for it. Through this process, it was possible to subdivide the functions of the product and to easily explore the working principle for each. The searched working principles are devised as various design alternatives by various combinations, and for each proposal, the advantages and disadvantages were compared with each other to derive the optimal design alternative. In the basic design, the prototype layout was completed through failure mode analysis and the actual prototype was manufactured using it. Through the entire process, students participating in the class will be able to design commercial products in a systematic way and experience manufacturing prototypes within the department of mechanical engineering curriculum.

• Journal of Korean Elementary Science Education
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• v.41 no.2
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• pp.325-337
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• 2022

This study aims to determine the implications of the efficient and effective implementation of science core competency (ScC) education by examining the state of science core competencies derived from the 2015 revised elementary school science curriculum and analyzing teachers' and students' perceptions. To this end, this paper investigated the reality of reflecting the science core competencies of science textbooks in a group of third and fourth graders from seven elementary schools who passed the test. In addition, in-depth interviews were conducted with four elementary school teachers who participated in qualification textbook selection, and 156 elementary school students were surveyed to determine their perceptions of science core competencies. Findings showed that, first, 1,586 science core competencies were reflected throughout the textbooks, with an average of 227 per textbook and biology being the most salient area. Second, teachers did not understand the difference between previous inquiry activities in textbooks and ScC education. Third, no statistically significant differences were observed in the perceptions of male and female students on science core competencies, the highest average of perceptions being those of scientific thinking ability. From these results, this study concluded that for ScC education to be realized as a curriculum, textbooks must be organized according to the purpose of core competency education, implementing practical changes, and efforts must be directed toward changing the perceptions of individuals who deliver education.

• Animal Bioscience
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• v.35 no.12
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• pp.1827-1838
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• 2022

Objective: The semen quality of stallions including sperm motility is an important target of selection as it has a high level of individual variability. However, effects of the molecular architecture of the genome on the mechanisms of sperm formation and their preservation after thawing have been poorly investigated. Here, we conducted a genome-wide association study (GWAS) for the sperm motility of cryopreserved semen in stallions of various breeds. Methods: Semen samples were collected from the stallions of 23 horse breeds. The following semen characteristics were examined: progressive motility (PM), progressive motility after freezing (FPM), and the difference between PM and FPM. The respective DNA samples from these stallions were genotyped using Axiom Equine Genotyping Array. Results: We performed a GWAS search for single nucleotide polymorphism (SNP) markers and potential genes related to motility properties of frozen-thawed semen in the stallions of various breeds. As a result of the GWAS analysis, two SNP markers, rs1141327473 and rs1149048772, were identified that were associated with preservation of the frozen-thawed stallion sperm motility, the relevant putative candidate genes being NME/NM23 family member 8 (NME8), olfactory receptor family 2 subfamily AP member 1 (OR2AP1), and olfactory receptor family 6 subfamily C member 4 (OR6C4). Potential implications of effects of these genes on sperm motility are herein discussed. Conclusion: The GWAS results enabled us to localize novel SNPs and candidate genes for sperm motility in stallions. Implications of the study for horse breeding and genetics are a better understanding of genomic regions and candidate genes underlying stallion sperm quality, and improvement in horse reproduction and breeding techniques. The identified markers and genes for sperm cryotolerance and the respective genomic regions are promising candidates for further studying the biological processes in the formation and function of the stallion reproductive system.

• Industry Promotion Research
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• v.7 no.3
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• pp.125-130
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• 2022

The purpose of this study is to develop music psychotherapy program applying the Inner Family System(IFS) to reduce adult depression and improve self-esteem and to verify its effectiveness. For this, literature search and theoretical basis were prepared, and validity was secured through a demand survey and evaluation by experts. After going through the preliminary program, the final program consisting of 10 sessions was developed after revision and supplementation. To verify the effectiveness of the program, 25 people who met the selection criteria with a score of 20 or higher on the Depression Scale(CES-D) were selected. Of the 25 subjects, 10 subjects in the experimental group, 10 subjects in the control group, and 5 subjects in the preliminary group were randomly assigned and analyzed as final study subjects. The experimental group performed 10 sessions of music psychotherapy applying IFS twice a week for 90 minutes, and the control group did not receive any treatment. As a result of data analysis, first, it was confirmed that there was a difference between the experimental group and the control group in the change patterns according to the measurement period of overall depression and the sub-factors, depressive emotion, interpersonal emotion, and physical depression score. Second, the effects were statistically significant on overall self-esteem and sub-factors such as self-deprecation, relationship with others, leadership and popularity, assertion and anxiety. Third, it was confirmed that the pattern of change according to the measurement period of the IFS score differed between the experimental and control groups.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.5
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• pp.835-842
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• 2022

Several countries are establishing management systems for aquaculture environment, and fishery environment assessment is one of them. The fishery management law amended in 2013 stipulates that a fishery environment assessment should be performed when a fish cage farm's license is extended. The purpose of the fishery environment assessment is to promote sustainable fishery, increase the fishery production capacity, and increase the fishermen incoming by implementing evaluation and improvement measures through scientific methods. The analysis items of fishery environment assessment include the Benthic Health Index (BHI), which is a biological index based on the macrobenthic polychaetes community, and total organic carbon (TOC), and the two items are scored and used for evaluation as a single grade. This study explains the selection process of BHI and TOC, which are evaluation items for fishing ground, and ecological significance of the calculated evaluation grades.