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        검색결과 3,041

        21.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study conducted a critical discourse analysis (CDA) of Maria Leonor “Leni” G. Robredo’s presidential proclamation bid considering differing ideologies between two opposing political parties in the Philippines. Robredo employed language to persuade people to support her ideologies and, ultimately, to cast their votes for her. Analyzing her speech through Fairclough’s three-dimensional CDA model yielded the following several key insights. First, the textual analysis of Robredo’s proclamation bid revealed multiple personal and impersonal motivations in using linguistic markers such as personal pronouns, mood, and modality. Second, the processing analysis of Robredo’s political discourse displayed her lexical choices and use of rhetorical norms such as metaphors, repetition, and three-part lists to persuade people to change their views on the government. Finally, the social analysis of Robredo’s proclamation speech revealed her ideologies as a political leader, which became the basis for constructing a self-identity relevant to her orientation of power. This analysis of Robredo’s political discourse through CDA explored the relationship between language, ideologies, and power. The findings of this study are expected to stimulate listeners to critically observe the verbal political behaviors of speakers.
        9,200원
        22.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The chemical composition of 86 species of native plants in Korea, including plants to be afforestation, was analyzed. The chemical composition of the species analyzed was different. The species with the highest extractable content was Viburnum dilatatum (3.91%), and the species with the lowest extractable content was Ligustrum lucidum (0.11%). The lignin content ranged from 12 to 39%, with an average of 25%. The species with the highest lignin content was Chaenomeles lagenaria (39.37%). Hemicellulose content ranged from 18 to 52%, with the highest species being Thuja occidentalis (51.22%) and Eucommia ulmoides (48.84%). Cellulose content ranged from 25 to 58%, and the species with the highest content were Prunus serrulata (57.67%), Diospyros kaki (57.14%), Aesculus turbinata (53.29%), Albizia julibrissin (53.02%), and Zelkova serrata (52.29%). The chemical composition was different for each use taxon of 86 plant species. The lignin content was the highest in the fruit group and the lowest in the group other than recommended species for afforestation. Cellulose content was highest in non-reforestation-recommended tree species and lowest in fruit trees. In classification according to tree height, lignin content was higher in shrubs than in tall trees, and cellulose content was highest in tall trees. Between deciduous and evergreen trees, the lignin content was high in deciduous trees (26.46%), and the cellulose content was also high in deciduous trees (44.01%). As a result of analyzing the correlation between each compound, there was a difference. There tended to be a positive correlation between extractives and lignin content. There was a negative correlation between extractives and holocellulose content, hemicellulose and cellulose. The higher extract content affected the cellulose content much more than hemicellulose. Also, the higher the lignin content, the lower the cellulose content. The species with low lignin content and high cellulose content were Diospyros kaki and Prunus serrulata var. spontanea. This result is expected to be primary data for bioenergy, pulp industry and bioindustry.
        4,200원
        23.
        2024.01 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer (SPHEREx) will provide all-sky spectral survey data covering optical to mid-infrared wavelengths with a spatial resolution of 6.′′2, which can be widely used to study galaxy formation and evolution. We investigate the galaxy-galaxy blending in SPHEREx datasets using the mock galaxy catalogs generated from cosmological simulations and observational data. Only ∼0.7% of the galaxies will be blended with other galaxies in all-sky survey data with a limiting magnitude of 19 AB mag. However, the fraction of blended galaxies dramatically increases to ∼7–9% in the deep survey area around the ecliptic poles, where the depth reaches ∼22 AB mag. We examine the impact of the blending in the number count and luminosity function analyses using the SPHEREx data. We find that the number count can be overestimated by up to 10–20% in the deep regions due to the flux boosting, suggesting that the impact of galaxy-galaxy blending on the number count is moderate. However, galaxy-galaxy blending can marginally change the luminosity function by up to 50% over a wide range of redshifts. As we only employ the magnitude limit at Ks-band for the source detection, the blending fractions determined in this study should be regarded as lower limits.
        4,000원
        24.
        2024.01 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This research investigated the preparation of activated carbon derived from Krabok (Irvingia malayana) seed shells to improve the quality of crude glycerol obtained during biodiesel production. The activated carbon was prepared using a dry chemical activation method with NaOH, utilizing an innovative biomass incinerator. The results revealed that the resulting KC/AC-two-step exhibited favorable physicochemical adsorption properties, with a high surface area of 758.72 m2/g and an iodine number of 611.10 mg/g. These values meet the criteria of the industrial product standard for activated carbon No. TIS 900-2004, as specified by the Ministry of Industry in Thailand. Additionally, the adsorption efficiency for methylene blue reached an impressive 99.35 %. This developed activated carbon was then used to improve the quality of crude glycerol obtained from biodiesel production. The experimental results showed that the KC/AC-two-step increased the purity of crude glycerol to 73.61 %. In comparison, commercially available activated carbon (C/AC) resulted in a higher crude glycerol purity of 81.19 %, as analyzed by the GC technique. Additionally, the metal content (Zn, Cu, Fe, Pb, Cd, and Na) in purified glycerol using KC/AC-two-step was below the standards for heavy metals permitted in food and cosmeceuticals by the Food and Drug Administration of Thailand and the European Committee for Food Contact Materials and Articles. As a result, it can be inferred that Krabok seed shells have favorable properties for producing activated carbon suitable as an adsorbent to enhance crude glycerol purity. Furthermore, the improved crude glycerol from this research has potential for various industrial applications.
        4,200원
        25.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Carbon nanofibers (CNFs) are promising materials for the construction of energy devices, particularly organic solar cells. In the electrospinning process, polyacrylonitrile (PAN) has been utilized to generate nanofibers, which is the simplest and most popular method of creating carbon nanofibers (CNFs) followed by carbonization. The CNFs are coated on stainless steel (SS) plates and involve an electropolymerization process. The prepared Cu, CNF, CNF–Cu, PANI, PANI–Cu, CNF–PANI, and CNF–PANI–Cu electrode materials’ electrical conductivity was evaluated using cyclic voltammetry (CV) technique in 1 M H2SO4 electrolyte solution. Compared to others, the CNF–PANI–Cu electrode has higher conductivity that range is 3.0 mA. Moreover, the PANI, CNF–PANI, and CNF–PANI–Cu are coated on FTO plates and characterized for their optical properties (absorbance, transmittance, and emission) and electrical properties (CV and Impedance) for organic solar cell application. The functional groups, and morphology-average roughness of the electrode materials found by FT–IR, XRD, XPS, SEM, and TGA exhibit a strong correlation with each other. Finally, the electrode materials that have been characterized serve to support and act as the nature of the hole transport for organic solar cells.
        4,500원
        26.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The dyeing process is a very important unit operation in the leather and textile industries; it produces significant amounts of waste effluent containing dyes and poses a substantial threat to the environment. Therefore, degradation of the industrial dye-waste liquid is necessary before its release into the environment. The current is focusing on the reduction of pollutant loads in industrial wastewater through remediating azo and thiazine dyes (synthetic solutions of textile dye consortium). The current research work is focused on the degradation of dye consortium through photo-electro-Fenton (PEF) processes via using dimensionally stable anode (Ti) and graphite cathode. The ideal conditions, which included a pH of 3, 0.1 (g/L) of textile dye consortium, 0.03 (g/L) of iron, 0.2 (g/L) of H2O2, and a 0.3 mAcm-2 of current density, were achieved to the removal of dye consortium over 40 min. The highest dye removal rate was discovered to be 96%. The transition of azo linkages into N2 or NH3 was confirmed by Fourier transforms infra-red spectroscopic analysis. PEF process reduced the 92% of chemical oxygen demand (COD) of textile dye consortium solution, and it meets the kinetics study of the pseudo-first-order. The degradation of dye through the PEF process was evaluated by using the cyclic voltammetric method. The toxicity tests showed that with the treated dye solution, seedlings grew well.
        4,800원
        27.
        2023.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The aim of this study is to ensure the structural integrity of a canister to be used in a dry storage system currently being developed in Korea. Based on burnup and cooling periods, the canister is designed with 24 bundles of spent nuclear fuel stored inside it. It is a cylindrical structure with a height of 4,890 mm, an internal diameter of 1,708 mm, and an inner length of 4,590 mm. The canister lid is fixed with multiple seals and welds to maintain its confinement boundary to prevent the leakage of radioactive waste. The canister is evaluated under different loads that may be generated under normal, off-normal, and accident conditions, and combinations of these loads are compared against the allowable stress thresholds to assess its structural integrity in accordance with NUREG-2215. The evaluation result shows that the stress intensities applied on the canister under normal, off-normal, and accident conditions are below the allowable stress thresholds, thus confirming its structural integrity.
        4,300원
        28.
        2023.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        A transfer cask serves as the container for transporting and handling canisters loaded with spent nuclear fuels from light water reactors. This study focuses on a cylindrical transfer cask, standing at 5,300 mm with an external diameter of 2,170 mm, featuring impact limiters on the top and bottom sides. The base of the cask body has an openable/closable lid for loading canisters with storage modules. The transfer cask houses a canister containing spent nuclear fuels from lightweight reactors, serving as the confinement boundary while the cask itself lacks the confinement structure. The objective of this study was to conduct a structural analysis evaluation of the transfer cask, currently under development in Korea, ensuring its safety. This evaluation encompasses analyses of loads under normal, off-normal, and accident conditions, adhering to NUREG-2215. Structural integrity was assessed by comparing combined results for each load against stress limits. The results confirm that the transfer cask meets stress limits across normal, off-normal, and accident conditions, establishing its structural safety.
        4,600원
        29.
        2023.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        With South Korea increasingly focusing on nuclear energy, the management of spent nuclear fuel has attracted considerable attention in South Korea. This study established a novel procedure for selecting safety-relevant radionuclides for long-term safety assessments of a deep geological repository in South Korea. Statistical evaluations were performed to identify the design basis reference spent nuclear fuels and evaluate the source term for up to one million years. Safety-relevant radionuclides were determined based on the half-life criteria, the projected activities for the design basis reference spent nuclear fuel, and the annual limit of ingestion set by the Nuclear Safety and Security Commission Notification No. 2019-10 without considering their chemical and hydrogeological properties. The proposed process was used to select 56 radionuclides, comprising 27 fission and activation products and 29 actinide nuclides. This study explains first the determination of the design basis reference spent nuclear fuels, followed by a comprehensive discussion on the selection criteria and methodology for safety-relevant radionuclides.
        4,500원
        30.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: This study helps to evaluate the Ovarian potential of Cameroonian Zebu cattle (Bos indicus) slaughtered in Etoudi – Yaoundé for implementing Assisted Reproductive Techniques (ARTs). The aim was to enhance the productivity of the cattle sub-sector in Cameroon while conserving local genetic resources. Methods: A total of 144 cows, including 94 cycled cows and 50 pregnant cows, were included in the study. Live weights were determined by measuring the thoracic perimeter of each cow using a Rondo measuring tape. Age was determined postmortem through examination of dentition and horns, while the uterus and ovaries were removed, weighed, and classified based on physiological status (pregnant or nonpregnant). Follicles were counted, and their diameters were measured and categorized into small (Ø < 3 mm), medium (Ø 3-8 mm), and large (Ø > 8 mm). Results: The results revealed an average follicular population of 32.02 ± 9.31 per cow, with 22.43 ± 8.45 small follicles, 8.42 ± 3.87 medium follicles, and 0.76 ± 0.34 large follicles. The weight of the right ovary was significantly higher than that of the left ovary (p < 0.05), and cows aged 6 to 9 years exhibited a higher number of follicles compared to other age groups. Cows with medium (BCS = 3) and large (BCS = 4-5) body reserves had the heaviest ovaries. Additionally, pregnant cows had heavier uteri compared to non-pregnant cows, and cows with a body condition score of 3 or higher had higher uterine weights than lean cows (BCS = 1-2). Conclusions: This study demonstrates that age, body condition score, and pregnancy status influence ovarian weight. Body Condition Score serves as a reliable indicator of cow nutritional status, and cows with BCS of 3-5 are excellent candidates for in vitro production of embryos.
        4,200원
        31.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Canine induced pluripotent stem cells (iPSCs) are an attractive source for veterinary regenerative medicine, disease modeling, and drug development. Here we used vitamin C (Vc) to improve the reprogramming efficiency of canine iPSCs, and its functions in the reprogramming process were elucidated. Methods: Retroviral transduction of Oct4, Sox2, Klf4, c-Myc (OSKM), and GFP was employed to induce reprogramming in canine fetal fibroblasts. Following transduction, the culture medium was subsequently replaced with ESC medium containing Vc to determine the effect on reprogramming activity. Results: The number of AP-positive iPSC colonies dramatically increased in culture conditions supplemented with Vc. Vc enhanced the efficacy of retrovirus transduction, which appears to be correlated with enhanced cell proliferation capacity. To confirm the characteristics of the Vc-treated iPSCs, the cells were cultured to passage 5, and pluripotency markers including Oct4, Sox2, Nanog, and Tra-1-60 were observed by immunocytochemistry. The expression of endogenous pluripotent genes (Oct4, Nanog, Rex1, and telomerase) were also verified by PCR. The complete silencing of exogenously transduced human OSKM factors was observed exclusively in canine iPSCs treated with Vc. Canine iPSCs treated with Vc are capable of forming embryoid bodies in vitro and have spontaneously differentiated into three germ layers. Conclusions: Our findings emphasize a straightforward method for enhancing the efficiency of canine iPSC generation and provide insight into the Vc effect on the reprogramming process.
        4,000원
        32.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Pigs are considered a “mixing vessel” that can produce new influenza strains through genetic reassortments, which threaten public health and cause economic losses worldwide. We performed surveillance of swine influenza virus (SIV) using 114,140 nasal swabs from 11,414 Korean farms from 2009 to 2022, and characterized their genetic evolution at each farm level. A total of 169 farms out of the 11,414 (1.48%) were SIV-positive. The positivity rate for the H1N2 subtype, which is most dominant in the pig population, was 37.87% (64/169). Through hemagglutinin (HA) gene analysis, 64 H1N2-positive farms were classified into Eurasian avian-like (46/64, 71.88%), triple-reassortant (14/64, 21.88%), pdm09 (3/64, 4.69%), and classical swine (1/64, 1.56%) groups. The estimated evolutionary rate of HA in H1N2 from 2009 to 2022 in Korea is 1.5309 × 10-3/site/year (95% HPD intervals from 1.0003 × 10-3 to 2.1735 × 10-3) with an estimated mean growth rate of 0.0114. Estimates of the relative genetic diversity of clades over time suggested that the HA of H1N2 exhibited an increase in population size. The results of this study showed that the Eurasian avian-like-HA of the H1N2 subtype was dominant in the pig population. The continued evolution of the HA of H1N2, which is critical for cell entry, might lead to genetic diversity and the loss of vaccine cross-protection. These results indicate that continus surveillance is imperative for monitoring the evolution of the swine influenza virus.
        4,000원
        33.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The primary therapeutic approach for Brucella species infections has mainly been based on antibiotic treatment. However, the development of vaccines for brucellosis control remains controversial. Furthermore, there is currently no licensed vaccine available for human brucellosis. This study aims to evaluate the effect of a combination of recombinant protein vaccines against Brucella (B.) abortus infection using a mouse model. Two B. abortus genes, namely dapB and gpm, were cloned and expressed in competent Escherichia (E.) coli DH5α using the pCold-TF vector. Successfully cloned vectors were subjected to PCR amplification using specific primer pairs. The apparent sizes of dapB and gpm were detected at 807 bp and 621 bp, respectively. Besides, the purified recombinant proteins dapB and gpm were detected using SDS-PAGE electrophoresis with correct sizes of 82.86 kDa and 87.61 kDa, respectively. These recombinant proteins were used to immunize mice as a combined subunit vaccine (CSV) to elicit host immunity against B. abortus infection. Mice immunized with CSV exhibited increased proliferation of CD4+ and/or CD8+ T cells at week 7th and 9th before sacrifice, in comparison to the control group. Notably, CSV immunization showed a significant decrease in bacterial burden in the spleen compared to the control group. Altogether, CSV using dapB and gpm induced host adaptive immune response against Brucella infection, suggesting its potential as an effective new subunit vaccine candidate.
        4,000원
        34.
        2023.12 구독 인증기관 무료, 개인회원 유료
        Efficiently detecting the nearest navigational dangers in Electronic Chart Display and Information Systems (ECDIS) remains pivotal for maritime safety. However, the software implementation of ADMAR(Automatic Distance measurement and Ranging) functionality faced challenges, necessitating extensive computations across ENC cells and impacting real-time performance. To address this, we present a novel method employing dynamic programming. Our proposed algorithm strategically organizes nodes into a tree structure, optimizing the search process towards nodes likely to contain navigational hazards. Implementation of this method resulted in a notable sevenfold reduction in computation time compared to the conventional Brute Force approach. Our study established a direct correlation between the ADMAR functionality and node count, achieving error margins deemed acceptable for practical navigation scenarios. Despite this theoretical progress, minor errors in results prompt further refinement. Consequently, future iterations will explore varying values for N, considering hierarchy and cell sizes to enhance algorithmic precision. This research signifies a potential advancement in optimizing navigational danger detection within ECDIS, offering a promising avenue for improved efficiency. By introducing a dynamic programming-based approach, we have streamlined the detection process while acknowledging the scope for algorithmic refinement in subsequent studies. Our findings underline the feasibility of employing dynamic programming to enhance navigational danger detection, emphasizing its potential in ensuring maritime safety. This work lays a foundation for future research endeavors, aiming to fine-tune algorithms and advance navigational safety measures in ECDIS.
        4,000원
        35.
        2023.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Cardiovascular disease remains a leading global cause of mortality, demanding effective prevention and management. This systematic review explores the impact of lycopene, prevalent in various fruits, on cardiovascular health. Thirteen randomized and controlled trials were analyzed, involving 385 participants with cardiovascular risk factors. Notable findings included significant blood pressure reductions, particularly among hypertensive individuals, and favorable alterations in lipid profiles. Lycopene interventions also demonstrated potential in mitigating oxidative stress and inflammation markers. While these findings show promise, more rigorously designed studies are essential to determine optimal dosages and durations for precise cardiovascular benefits. In conclusion, lycopene shows potential in managing cardiovascular risk factors, and its role in blood pressure regulation, lipid profile improvement, and antioxidant and anti-inflammatory effects is encouraging. Nonetheless, further research is warranted to provide definitive guidance on integrating lycopene to enhance cardiovascular health.
        4,000원
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