검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 310

        1.
        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
        2.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        해사영어는 선박 운항, 해양 안전, 선내 의사소통 및 선외 교신을 위해 설계된 특수한 영어 언어체계이다. 국제해사기구 STCW(선원의 훈련, 자격증명 및 당직근무의 기준에 관한 국제협약)에 따르면 국제항해에 종사하는 항해사가 되기 위해서는 SMCP를 포함한 해사영어 대한 충분한 이해가 수반되어야 한다. 본 연구는 음성인식, 번역, 단어 기입 등 유형의 해사영어시험을 통하여 학생들 의 해사영어 활용 능력을 측정하고 플랫폼 사용에 따른 시험 점수 향상 정도, 나아가 초임항해사로 나가기 위하여 요구되는 해사영어 시험 플랫폼 활용 시간 등을 조사하고자 하였다. 실험은 먼저 초기 시험을 통해 학생들의 일반영어능력과 SMCP 활용 능력에 대한 연 관성을 조사한 후, 중간 시험 및 최종 시험을 통해 플랫폼 활용에 대한 점수 향상 정도, 응시시간 변화 등 요인을 측정하였다. 초기 시 험을 통해 개인 요인(예: 토익 점수, 본인 스스로에 대한 영어능력 평가)에 따른 그룹 간 해사영어시험 점수에 유의한 차이가 있음을 확인하였으며, 중간시험 및 최종시험을 통해 플랫폼 활용이 유의한 시험점수 향상으로 이어졌음을 확인하였다. 해당 연구는 해사 교육 분야에 다양하게 적용할 수 있는 학습 플랫폼 활용 효능을 조사하였으며 향후 해사영어 교육 외 그 범위를 넓혀 활용될 수 있을 것으 로 사료된다.
        4,000원
        3.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Estrus in cows can be detected through vaginal electrical resistance or conductivity. However, there are no studies measuring vaginal electrical resistance in Hanwoo cows. This study aims to measure the vaginal electrical resistance value in Hanwoo cows and compare it with estrus and ovulation. Methods: Vaginal electrical resistance values of 73 Hanwoo cows were measured before and after estrus at the Gyeongsangbuk-do Livestock Research Institute. Measurements were taken on days -6, -3, -2, -1, 0, 1, 2, 3, and 6 of artificial insemination. Large follicles and ovulation were confirmed using transvaginal ultrasonography. Results: The vaginal electrical resistance averaged 225.6 ± 6.3 Ω days before the artificial insemination date, decreasing until the day of artificial insemination. The average vaginal electrical resistance was 163.7 ± 4.6 Ω on the date of artificial insemination, and 188.8 ± 4.3 Ω one day after artificial insemination, when large follicles were observed. In addition, on the 6th day after artificial insemination, the vaginal electrical resistance averaged 231.4 ± 5.5, which was similar to the 6th day before artificial insemination (222.5 ± 6.3). Transvaginal ultrasonography showed that most of the cows ovulated one day after artificial insemination. Conclusions: The accuracy of estrus is high if the vaginal electrical resistance is measured for cows with confirmed estrus, making is a potentially useful for determining the timing of artificial insemination.
        4,000원
        4.
        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
        5.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, we examined the antagonistic effects of sprout-borne lactic acid bacteria (LAB) on Salmonella enterica serovar Enteritidis. This antagonism is promoted as a means of controlling contamination during sprout production and provides additional LAB for consumers. We isolated a total of 24 LAB isolates in nine species and five genera from seven popular vegetable sprouts: alfalfa (Medicago sativa), clover (Trifolium pratense), broccoli (Brassica oleracea ssp. italica), vitamin (B. rapa ssp. narinosa), red radish (Raphanus sativus), red kohlrabi (B. oleracea var. gongylodes), and Kimchi cabbage (B. campestris var. pekinensis). Based on 16S rRNA gene sequences, the LAB species were identified as Enterococcus casseliflavus, E. faecium, E. gallinarum, E. mundtii, Lactococcus taiwanensis, Leuconostoc mesenteroides, Pediococcus pentosaceus, and Weissella cibaria, and W. confusa. A total of 16 LAB isolates in seven species including E. faecium, E. gallinarum, E. mundtii, L. taiwanensis, L. mesenteroides, P. pentosaceus, and W. cibaria showed antagonistic activity toward S. enterica. The growth inhibition of sprout LAB on S. enterica was confirmed by co-culture. Unexpectedly, sprout LAB failed to suppress the growth of S. enterica in alfalfa sprouts, whereas all LAB strains stimulate S. enterica growth even if it is not significant in some strains. The findings of this study indicate that S. enterica-antagonistic LAB are detrimental to food hygiene and will contribute to further LAB research and improved vegetable sprout production.
        4,000원
        7.
        2023.11 구독 인증기관·개인회원 무료
        As the acceptance criteria for low-intermediate-level radioactive waste cave disposal facilities of Korea Radioactive Waste Agency (KORAD) were revised, the requirements for characterization of whether radioactive waste contains hazardous substances have been strengthened. In addition, As the recent the Nuclear Safety and Security Commission Notice (Regulations on Delivery of Low- Medium-Level Radioactive Waste) scheduled to be revised, the management targets and standards for hazardous substances are scheduled to be specified and detailed. Accordingly, the Korea Atomic Energy Research Institute (KAERI) needs to prepare management methods and procedures for hazardous substances. In particular, in order to characterize the chemical requirements (explosiveness, ignitability, flammability, corrosiveness, and toxicity) contained in radioactive waste, it must be proven through documents or data that each item does not contain hazardous substances, and quality assurance for the overall process must be provided. In order to identify the characteristics of radioactive waste that will continue to be generated in the future, KAERI needs to introduce a management system for hazardous substances in radioactive waste and establish a quality assurance system. Currently, KAERI is thoroughly managing chelates (EDTA, NTA, etc.), but the detailed management procedures for hazardous substances related to chemical requirements in radioactive waste in the radiation management area specified above are insufficient. The KAERI’s Laboratory Safety Information Network has a total periodic regulatory review system in place for the purchase, movement, and disposal of chemical substances for each facility. However, there is no documents or data to prove that the hazardous substances held in the facility are not included in the radioactive waste, and there are no procedures for managing hazardous substances. Therefore, it is necessary to establish procedures for the management of hazardous substances, and we plan to prepare management procedures for hazardous substances so that chemical substances can be managed according to the procedures at each facility during preliminary inspection before receiving radioactive waste. The procedure provides definitions of terms and types of management targets for each characteristic of the chemical requirements specified above (explosiveness, ignition, flammability, corrosiveness, and toxicity). In addition, procedure also contains treatment methods of radioactive waste generated by using hazardous substances and management methods of in/out, quantity, history of that substances, etc. As the law is revised in the future, management will be carried out according to the relevant procedures. In this study, we aim to present the hazardous substance management procedures being established to determine whether radioactive waste contains hazardous substances in accordance with the revised the notice and strengthened acceptance criteria. Through this, we hope to contribute to improving reliability so that radioactive waste could be disposed of thoroughly and safely.
        8.
        2023.10 구독 인증기관·개인회원 무료
        본 연구에서는 영종도에 위치한 인천과학고등학교 주변에 서식하는 개미와 개미집 근권토양을 두 차례에 걸쳐 채취한 것을 활용하여 토양미생물 순수분리 및 동정을 진행하였다. 채취된 개미의 더듬이의 모양, 털의 위치 및 분포 등의 형태학적 동정 및 DNA extraction을 통한 분자생물학적 동정을 통하여 채취한 개미를 Camponotus japonicus으로 결론하였다. 토양미생물을 연속희석법을 이용하여 확인한 결과 채취한 개미집 세 곳에서 각각 12, 18, 10개의 종이 동정되었다. 개미집 근권토양의 비옥도가 상대적으로 높다는 선행연구를 바탕 으로 ‘분리한 토양미생물이 다양한 유기물 분해 효소활성을 보일 것’이라는 가설을 세웠고, 이를 확인하기 위해 분별배지를 제작하여 디스크 확산법을 진행하였다. 실험 결과 개미집 근권 토양에서 분리된 균주가 일반 토양에 서 분리된 균주에 비해 높은 효소활성을 보임을 확인하였으며 개미집 근권 토양 미생물의 불용성인산 가용화능 이 우수함을 확인하였다. 이후 위 실험들을 바탕으로 개미집 근권 토양 미생물이 식물 생장을 촉진시켜 미생물을 접종한 토양에서의 식물의 건조 질량이 증가하였음을 확인하였다.
        9.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        목적 : 건강한 20대를 대상으로 각막내피세포의 형태학적 분석을 실시하고, 양안, 성별, 굴절교정수술 여부, 콘택트렌즈 착용여부, 코로나바이러스-19의 감염에 따른 차이를 알아보고자 하였다. 방법 : 충청남도 일개 대학교에서 20대 남녀 87명(174안)을 대상으로 하였다. 각막내피세포의 형태학적 분석 은 비접촉식 경면현미경을 이용하여 검사하였고, 각막내피세포의 밀도, 내피세포의 다형성, 육각형비율, 그리고 중심각막두께를 분석하였다. SPSS 18.0 프로그램을 이용하여 양안, 성별, 그리고 그 외에 조사한 변수에 따른 각 막내피세포의 밀도, 다형성 및 육각형 비율을 측정하였다. 결과 : 우안과 좌안에서 각막내피세포의 밀도는 각각 2,977.7±238.7 cells/mm2와 3,008.9±236.7 cells/mm2(p=0.056)이었고, 남성과 여성은 각각 2,970.9±237.9 cells/mm2와 2,983.6±241.8 cells/mm2로 통 계적으로 유의한 차이가 없었다(p=0.807). 각막내피세포의 다형성과 육각형 비율도 양안, 성별, 굴절교정수술 여 부. 코로나바이러스-19 감염 유무에 따라 유의한 차이가 없었다(p>0.050). 그러나 각막내피세포의 다형성과 육각 형 비율은 콘택트렌즈 착용 군과 대조군에서 각각 30.7±4.5%와 61.9±5.4% 그리고 28.2±4.0%와 64.7±4.7% 를 보였다(각각 p=0.018와 p=0.029). 결과 : 한국 20대 성인을 대상으로 분석한 각막내피세포 밀도의 평균값은 2,993.3±237.5 cells/mm2이었고, 양안과 성별에 따른 차이는 없었다.
        4,200원
        10.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        목적 : 본 연구의 목표는 서울지역 20대 MZ세대 집단이 인식하는 해외 안경테 브랜드 국가의 감성의미를 도출 하는 것이다. 방법 : 먼저 연구 대상으로 이탈리아, 프랑스, 미국, 일본 4개국을 선정하였다. 의미분별법을 이용하여 감성어 휘 8개를 추출한 다음, 설문조사와 통계처리를 통하여 각각의 국가별로 해당되는 감성어휘를 결정하였고, 해외 안 경테 브랜드 국가에 대한 선호도 조사를 추가로 실시하였다. 결과 : 이탈리아, 프랑스, 미국, 일본의 4가지 해외 안경테 브랜드 국가들에 대하여 각각 고급스러움, 매력적 임, 실용적임, 동양적임이라는 감성어휘를 가장 많이 선택하였다. 안경테에 대한 선호도 순위는 이탈리아, 프랑스, 미국, 일본 순으로 나타났다. 결론 : 도출된 감성어휘들과 응답자들의 선호도를 분석했을 때, 고급스러움과 디자인적 측면을 중시하는 MZ세 대의 플렉스 소비 성향에는 이탈리아와 프랑스 브랜드의 안경테가 가정 적합한 것으로 여겨진다.
        4,300원
        11.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Extensive research and testing continue to be conducted for the development of vaccines targeting zoonotic diseases such as brucellosis. In this study, the potential of the DapB as a recombinant protein vaccine to effectively combat Brucella abortus 544 infection in BALB/c mice was evaluated. Western blotting assay results showed that recombinant protein DapB reacted with Brucella-positive serum, indicating its potential immunoreactivity. In vivo results showed that the peripheral blood CD4+ and CD8+ T cell population significantly increased in the DapB-immunized mice group after the first, second and third blood collection, compared to the control group that received PBS. Additionally, at the fourth blood collection, an increase in CD4+ T cell activation was observed in three vaccination groups compared to PBS negative control group. These results indicate the potential of DapB in stimulating cellular immunity. Fourteen days after infection, the bacterial load in the spleen was evaluated. The reduction in bacterial replication in the spleen by both DapB and RB51 highlights their protective efficacy against Brucella infection. These findings contribute to the ongoing efforts in developing effective vaccines against brucellosis and provide valuable insights for further research in this field.
        4,000원
        12.
        2023.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        There are many types of foam molding methods. The most commonly used methods are the pressure foaming method, in which foam resin is mixed with a foaming agent at high temperature and high pressure, and the normal pressure foaming method, which foams at high temperature without pressure. The polymer resins used for foaming have different viscosities. For foaming under normal pressure, they need to be designed and analyzed for optimal foaming conditions, to obtain resins with low melt-viscosity or a narrow optimal viscosity range. This study investigated how changes in viscosity, molding temperature, and cross-link foaming conditions affected the characteristics of the molded foam, prepared by blending rubber polymer with biodegradable resin. The morphologies of cross sections and the cell structures of the normal pressure foam were investigated by SEM analysis. Properties were also studied according to cross-link/foaming conditions and torque. Also, the correlation between foaming characteristics was studied by analyzing tensile strength and elongation, which are mechanical properties of foaming composites.
        4,000원
        13.
        2023.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, we have fabricated the phenolic resin (PR)/polyacrylonitrile (PAN) blend-derived core-sheath nanostructured carbon nanofibers (CNFs) via one-pot solution electrospinning. The obtained core-sheath nanostructured carbon nanofibers were further treated by mixed salt activation process to develop the activated porous CNFs (CNF-A). Compared to pure PAN-based CNFs, the activated PR/PAN blend with PR 20% (CNF28-A)-derived core-sheath nanostructured CNFs showed enhanced specific capacitance of ~ 223 F g− 1 under a three-electrode configuration. Besides, the assembled symmetric CNF28-A//CNF28-A device possessed a specific capacitance of 76.7 F g− 1 at a current density of 1 A g− 1 and exhibited good stability of 111% after 5,000 galvanostatic charge/discharge (GCD) cycles, which verifies the outstanding long-term cycle stability of the device. Moreover, the fabricated supercapacitor device delivered an energy density of 8.63 Wh kg− 1 at a power density of 450 W kg− 1.
        4,500원
        14.
        2023.05 구독 인증기관·개인회원 무료
        Natural uranium-contaminated soil in Korea Atomic Energy Research Institute (KAERI) was generated by decommissioning of the natural uranium conversion facility in 2010. Some of the contaminated soil was expected to be clearance level, however the disposal cost burden is increasing because it is not classified in advance. In this study, pre-classification method is presented according to the ratio of naturally occurring radioactive material (NORM) and contaminated uranium in the soil. To verify the validity of the method, the verification of the uranium radioactivity concentration estimation method through γ-ray analysis results corrected by self-absorption using MCNP6.2, and the validity of the pre-classification method according to the net peak area ratio were evaluated. Estimating concentration for 238U and 235U with γ-ray analysis using HPGe (GC3018) and MCNP6.2 was verified by 􀟙-spectrometry. The analysis results of different methods were within the deviation range. Clearance screening factors (CSFs) were derived through MCNP6.2, and net peak area ratio were calculated at 295.21 keV, 351.92 keV(214Pb), 609.31 keV, 1120.28 keV, 1764.49 keV(214Bi) of to the 92.59 keV. CSFs for contaminated soil and natural soil were compared with U/Pb ratio. CSFs and radioactivity concentrations were measured, and the deviation from the 60 minute measurement results was compared in natural soil. Pre-classification is possible using by CSFs measured for more than 5 minutes to the average concentration of 214Pb or 214Bi in contaminated soil. In this study, the pre-classification method of clearance determination in contaminated soil was evaluated, and it was relatively accurate in a shorter measurement time than the method using the concentrations. This method is expected to be used as a simple pre-classification method through additional research.
        15.
        2023.05 구독 인증기관·개인회원 무료
        Level measurement of liquid radwaste is essential for inventory management of treatment system. Among various methods, level measurement based on differential pressure has many advantages. First, it is possible to measure the liquid level of the system regardless of liquid type. Second, as the instrument doesn’t need to be installed near the tank, there is no need to contact the tank when managing it. Therefore, workers’ radiation dose from the system can be decreased. Finally, although it depends on the accuracy, the price of the instrument is relatively low. With these advantages, in general, liquid radwaste level in a tank is measured using differential pressure in the treatment system. Not only the advantages described above, there are some disadvantages. As the liquid in the system is waste, it is not pure but has some suspended materials. These materials can be accumulated in tanks and pipes where the liquids move to come into direct contact with pneumatic pipes that are essential in differential pressure instruments. As a result, in case of a treatment using heat source, the accumulated materials may become sludge causing interference in pneumatic pipes. And this can change the pressure which also affects the level measured. In conclusion, in case of liquid storage tanks in which the situation cannot be checked, the proficiency of an operator becomes important.
        16.
        2023.05 구독 인증기관·개인회원 무료
        Molten Salt Reactor (MSR) is one of Generation-IV nuclear reactors that uses molten salts as a fuel and coolant in liquid forms at high temperatures. The advantages of MSR, such as safety, economic feasibility, and scalability, are attributed from the fact that the molten salt fuel in a liquid state is chemically stable and has excellent thermo-physical properties. MSR combines the fuel and coolant by dissolving the actinides (U, Th, TRU, etc.) in the molten salt coolant, eliminating the possibility of a core meltdown accident due to loss of coolant (LOCA). Even if the molten salt fuel leaks, the radioactive fission products dissolved in the molten salt will solidify with the fuel salt at room temperature, preventing potential leakage to the outside. MSR was first demonstrated at ORNL starting with the Aircraft Reactor Experiment (ARE) in 1954 and was extended to the 7.4 MWth MSRE developed in 1964 and operated for 5 years. Recently, various start-ups, including TerraPower, Terrestrial Energy, Moltex Energy, and Seaborg, have been conducting research and development on various types of MSR, particularly focusing on its inherent safety and simplicity. While in the past, fluoride-based molten salt fuels were used for thermal neutron reactors, recently, a chlorine-based molten salt fuel with a relatively high solubility for actinides and advantageous for the transmutation of spent nuclear fuel and online reprocessing has been developing for fast neutron spectrum MSRs. This paper describes the development status of the process and equipment for producing highpurity UCl3, a fuel material for the chlorine-based molten salt fuel, and the development status of the gas fission product capturing technologies to remove the gaseous fission products generated during MSR operation. In addition, the results of the corrosion property evaluation of structural materials using a natural circulation molten salt loop will also be included.
        20.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Pain Neuroscience Education (PNE) is an educational approach that deals with the physiology of the nervous system as well as the pain system and refers to educating patients with chronic musculoskeletal disorders such as chronic back pain. Objectives: This study examined the effects of pain neuroscience education on patients with low back pain. Design: Systematic review. Methods: Electronic bibliographic databases of a regional information sharing system (RISS) and PubMed were searched to identify randomized controlled studies. In the final outcome, 43 publications were identified, and 13 studies met the inclusion criteria. Results: There were a total of 13 pain-related studies, including 11 studies using NPRS (VAS) and 2 studies using other pain measurement instruments. In NPRS, the effect size was 0.683, which had a medium effect size. In Roland morris disability questionnaire (RMDQ), the effect size was 0.544, which had a medium effect size. In Oswestry disability index (ODI), the effect size was 0.951, indicating a large effect size, but the confidence interval could not be obtained because there was only one study. Conclusion: Pain neuroscience education has positive effects on low back pain and disability index in related patients.
        4,000원
        1 2 3 4 5