• Journal of Powder Materials
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• v.29 no.2
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• pp.118-122
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• 2022

The synthesis of porous W by freeze-casting and vacuum drying is investigated. Ball-milled WO₃ powders and tert-butyl alcohol were used as the starting materials. The tert-butyl alcohol slurry is frozen at -25℃ and dried under vacuum at -25 and -10℃. The dried bodies are hydrogen-reduced at 800℃ and sintered at 1000℃. The XRD analysis shows that WO₃ is completely reduced to W without any reaction phases. SEM observations reveal that the struts and pores aligned in the tert-butyl alcohol growth direction, and the change in the powder content and drying temperature affects the pore structure. Furthermore, the struts of the porous body fabricated under vacuum are thinner than those fabricated under atmospheric pressure. This behavior is explained by the growth mechanism of tert-butyl alcohol and rearrangement of the powders during solidification. These results suggest that the pore structure of a porous body can be controlled by the powder content, drying temperature, and pressure.

• Journal of Korean Critical Care Nursing
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• v.15 no.3
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• pp.37-50
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• 2022

Purpose : This study aimed to examine the item characteristics of the Korean version of the intensive care experience questionnaire (K-ICEQ) using the Rasch analysis model of the item response theory. Methods : In this methodological study, the validity of the scale was examined, and a secondary analysis was conducted using cohort data of patients who were discharged from the intensive care units (ICU). Data from 891 patients who responded to the K-ICEQ upon ICU discharge were analyzed. The WINSTEP program was used to analyze item characteristics, including item difficulty, fit indices, appropriateness scale, and separation reliability. Results : The difficulty level of all 26 items of the K-ICEQ was appropriate, and the fit indices of the 25 items, except for item 18, were good. The 5-point scale of the K-ICEQ was not appropriate in the three subscales. The item separation reliability was good in all subscales, but did not meet the criteria in terms of respondents. Conclusion : The results of examining the item characteristics of the K-ICEQ revealed a good degree of difficulty, fitness, and item separation reliability. To increase the validity of the K-ICEQ, we suggest the rearrangement of the overall item order, modification of the item description of the "recall of experience" subscale, and reduction of the scale response level.

• Development and Reproduction
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• v.26 no.1
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• pp.23-36
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• 2022

Pharyngeal pouches, a series of outgrowths of the pharyngeal endoderm, are a key epithelial structure governing facial skeleton development in vertebrates. Pouch formation is achieved through collective cell migration and rearrangement of pouch-forming cells controlled by actin cytoskeleton dynamics. While essential transcription factors and signaling molecules have been identified in pouch formation, regulators of actin cytoskeleton dynamics have not been reported yet in any vertebrates. Cofilin1-like (Cfl1l) is a fish-specific member of the Actin-depolymerizing factor (ADF)/Cofilin family, a critical regulator of actin cytoskeleton dynamics in eukaryotic cells. Here, we report the expression and function of cfl1l in pouch development in zebrafish. We first showed that fish cfl1l might be an ortholog of vertebrate adf, based on phylogenetic analysis of vertebrate adf and cfl genes. During pouch formation, cfl1l was expressed sequentially in the developing pouches but not in the posterior cell mass in which future pouch-forming cells are present. However, pouches, as well as facial cartilages whose development is dependent upon pouch formation, were unaffected by loss-of-function mutations in cfl1l. Although it could not be completely ruled out a possibility of a genetic redundancy of Cfl1l with other Cfls, our results suggest that the cfl1l expression in the developing pouches might be dispensable for regulating actin cytoskeleton dynamics in pouch-forming cells.

• Composites Research
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• v.35 no.1
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• pp.23-30
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• 2022

Polycarbosilane(PCS) is an important precursor for melt-spinning the silicon carbide(SiC) fibers and manufacturing ceramics. The PCS is a metal-organic polymer precursor capable of producing continuous SiC fibers having excellent performance such as high-temperature resistance and oxidation resistance. The SiC fibers are manufactured through melt-spinning, stabilization, and heat treatment processes using the PCS manufactured by synthesis, purification, and control of the molecular structure. In this paper, we analyzed the effect of purification of unreacted substances and low molecular weight through solvent treatment of PCS and the effect of heat treatment at various temperatures change the polymerization and network rearrangement of PCS. Especially, we investigated the complex viscosity and structural arrangement of PCS precursors according to solvent treatment and heat treatment through the rheological properties.

• Journal of Genetic Medicine
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• v.19 no.1
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• pp.14-21
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• 2022

Complex chromosome rearrangements (CCRs) are structural chromosomal rearrangements involving at least three chromosomes and more than two breakpoints. CCR carriers are generally phenotypically normal but related to higher risk of recurrent miscarriage and having abnormal offspring with congenital anomalies. However, most of CCR carriers are not aware of their condition until genetic analysis of either abortus or affected baby or parental karyotyping is performed. Herein, we present the case that CCR carrier patients can be identified by preimplantation genetic testing of preimplantation embryos. An infertile male patient with severe oligoasthenoteratozoospermia was diagnosed balanced reciprocal translocation, 46,XY,t(3;11) (p26;p14) at first. After attempting the first preimplantation genetic testing for structural rearrangement (PGT-SR) cycle, we found the recurrent segmental gain or loss on 21q21.3-q22.3 of five out of nine embryos. As a result of karyotype re-analysis, the patient's karyotype showed a balanced CCR involving chromosomes 3, 11, and 21 with three breakpoints 3p26, 11p14, and 21q21. The patient underwent two PGT-SR cycles, and a pregnancy was established after the transfer of an euploid embryo in the second cycle. Amniocentesis confirmed that the baby carried normal karyotype without mosaicism. At 37 weeks gestation, a healthy girl weighting 3,050 g was born.

• The Korean Journal of Physiology and Pharmacology
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• v.27 no.3
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• pp.257-265
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• 2023

Kidney ischemia/reperfusion (I/R) injury, a common cause of acute kidney injury (AKI), is associated with the migration of inflammatory cells into the kidney. Ras-related C3 botulinum toxin substrate 1 (Rac1), a member of the Rho family of small GTPase, plays an important role in inflammatory cell migration by cytoskeleton rearrangement. Here, we investigated the role of Rac1 on kidney I/R injury and macrophage migration. Male mice were subjected to either 25 min of bilateral ischemia followed by reperfusion (I/R) or a sham operation. Some mice were administrated with either NSC23766, an inhibitor of Rac1, or 0.9% NaCl (vehicle). Kidney damage and Rac1 activity and expression were measured. The migration and lamellipodia formation of RAW264.7 cells, mouse monocyte/macrophage, induced by monocyte chemoattractant protein-1 (MCP-1, a chemokine) were determined using transwell migration assay and phalloidin staining, respectively. In sham-operated kidneys, Rac1 was expressed in tubular cells and interstitial cells. In I/R-injured kidneys, Rac1 expression was decreased in tubule cells in correlation with the damage of tubular cells, whereas Rac1 expression increased in the interstitium in correlation with an increased population of F4/80 cells, monocytes/macrophages. I/R increased Rac1 activity without changing total Rac1 expression in the whole kidney lysates. NSC23766 administration blocked Rac1 activation and protected the kidney against I/R-induced kidney damage and interstitial F4/80 cell increase. NSC23766 suppressed monocyte MCP-1-induced lamellipodia and filopodia formation and migration of RAW 264.7 cells. These results indicate Rac1 inhibition protects the kidney against I/R via inhibition of monocytes/macrophages migration into the kidney.

• 한국체육학회지인문사회과학편
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• v.54 no.5
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• pp.705-716
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• 2015

The purpose of this research is to explore the role of Taekwondo in foreign migrant workers' adaptation process in Korean society, based on segmented assimilation concept by Portes & Zhou(1993) as a theoretical framework. In order to achieve this, an in-depth interview of 13 foreign migrant workers in Gyeonggi-region was carried out by using purpose sampling and theoretical sampling together, and the interview was analyzed using grounded theory method. The analysis result demonstrated that foreign migrant workers understand Korean culture, learn Korean, and interact with Koreans through Taekwondo, which facilitates their acculturation into the mainstream society. Also, they were assimilated into their own subculture of being fascinated by the charms of Taekwondo and trying to become Taekwondo instructors by returning to their home country. Lastly, they built a social network and overcame tough labor and the difficulties of living in a foreign country through Taekwondo. This research is significant as it examined the role of Taekwondo that preserves Korean culture and checked its value, in terms of the adaptation of foreign migrant workers who take a part in the current rearrangement of Korean society into a multicultural society.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3B
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• pp.311-317
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• 2009

Similarity indices between sampling sites are calculated and cluster analysis of fish community is carried out by UPGMA based on investigating fish fauna and water environment. The restoration indicators as target species of Wonju stream are selected Cottus poecilopus, Zacco temmincki, and Zacco platypus along upper, middle, and lower streams, respectively. For better habitat suitability, low flow increasing and induced water quality improving must be secured by sewer system rearrangement and watershed management. Composite habitat suitability of Zacco temmincki as target species at middle stream of Wonju stream improve significantly by low flow increasing, which is very important factor to improve habitat suitability. The changes of hydraulics of depth and velocity govern the habitat suitability in general, but the effects are not significant. Low flow increasing with the change of 10% reducing of lower channel improves the composite habitat suitability of 0.37~0.78 to their origin of 0.1~0.25, which represent the channel restoration scheme of Wonju stream for enhancing the habitat suitability of fish community.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.34 no.1
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• pp.31-40
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• 2024

Recently, static analysis-based signature and pattern detection technologies have limitations due to the advanced IT technologies. Moreover, It is a compatibility problem of multiple architectures and an inherent problem of signature and pattern detection. Malicious codes use obfuscation and packing techniques to hide their identity, and they also avoid existing static analysis-based signature and pattern detection techniques such as code rearrangement, register modification, and branching statement addition. In this paper, We propose an LLVM IR image-based automated static analysis of malicious code technology using machine learning to solve the problems mentioned above. Whether binary is obfuscated or packed, it's decompiled into LLVM IR, which is an intermediate representation dedicated to static analysis and optimization. "Therefore, the LLVM IR code is converted into an image before being fed to the CNN-based transfer learning algorithm ResNet50v2 supported by Keras". As a result, we present a model for image-based detection of malicious code.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.159-176
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• 1996

This study is aimed at reviewing the methods of joint cost allocation and allocating the joint cost of estuary dam with specially repect to Kumgang Large-scale Agricultural Comprehensive Development Project. Apart from the water resource development project propelled by Water Resource Development Corporation in connection with Law of Multipurpose Dam Development, the Largescale Comprehensive Agricultural Development Projects couldn't ins-titutionally be carried out cost allocation of common facilities, even though it were concerned with irrigation, municipal and industrical water supply, flood control, sightseeing and industrial zone development components. To decrease farmer's burden of the project costs and, operation and maintenance costs, the joint costs of common facilities like estuary dam included in agricultural development projects have to be allocated by suitable method as alternative cost-remaining benefit method and the analytical activity should be supported by revising the concerned laws as Rural Development and Promotion and, Rural Rearrangement conpatible with the law for multipurpose dam development. Kumgang Agricultural Comprehensive Development Project was selected as a case study for the estimation of socio-economic benefits by project components and joint cost allocation of the estuary dam. The main results of the study are as follows; Joint cost allocation and unit charges by components 1. The project area will be 25,554ha with total project cost of 624,860 million won including the estuary dam cost of 120,843 million won. The project costs were ex-pressed by 1994 constant price. 2. Total quantity of water was estimated 365 million tons which were consisted of 245 million tons for irrigation, 73 million tons for municipal water and 47 million tons for industrial water. 3. The rates of joint cost allocation were amounted to 34.2% for agriculture, 2.5% for sightseeing, 45.7% for transportation, 11.8% for M & I water supply and 5.8% for flood control respectively. 4. The unit financial charges by project components were estimated at 7.88 won per ton for irrigation, 16.11won for M & I water, 1,686won per vehicle one pass, 977won per Pyeong according to the capital recovery method. The financial charges using straitline method for depreciation were estimated at 7.88won per ton for irrigation, 9.12won per ton for M & I water, 624won per vehicle one pass for transportation and 331won per Pyeong for sightseeing area. 5. The unit economic charges by project components were estimated at 21.1 won per ton for irrigation, 15.2won for M & I water, 977won per vehicle one pass, 977won per Pyeong according to the capital recovery method. The economic charges using straitline method for depreciation were estimated at 11.72won per ton for irrigation, 8.61won per ton for M & I water, 331won per vehicle one pass for transportation. Policy recommendation 1. The unit operation and maintenance costs for irrigation water in the paddy field couldn't be imposed as the water resource cost untreated. 2. The dam costs including investment cost and O & M cost, as a joint cost, had to be allocated by each benefited components as transportation, M & I water supply, flood control, irrigation and drainage, and sightseeing. But the agricultural comprehensive project have been dealt as an irrigation project without any appraisal socio-economic benefits and any allocating the joint cost of estuary dam. 3. All the associated project benefits and costs must be evaluated based on accounting principle and rent recovery rate of the project costs and O & M costs should be regulated by the laws concerned. 4. The rural development and promotion law and rural rearrangement law have to be revised comprising joint cost allocation considering free rider problems. 5. The government subsidy for the agricultural base development project has to be covered all the project costs. In case of common facilities representing joint cost allocation problems, all the allocated casts for other purposes like transportation and M & I water supply etc. should be recovered for formation in investment fund for agricultural base development and to procure O & M costs for irrigation facilities.