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        검색결과 187

        1.
        2024.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This paper evaluates the use of Factor Analysis (FA) in English education research in Korea and suggests improvements in methodology. A detailed coding protocol was used to review 179 FA cases from 12 major English education journals (2014-2023). The review identified several key issues, including small sample sizes and lenient criteria for sample size selection, insufficient reporting on data appropriateness and normality, confusion between principal component analysis and FA, overreliance on the Eigenvalue > 1 criterion for determining the number of factors, inappropriate factor rotation methods, inconsistency between factor rotation and extraction methods, inadequate reporting on factor loadings and cross loadings criteria, and excessive reliance on SPSS as a statistical tool for FA. This study provides specific guidelines for applying FA appropriately and reporting results accurately.
        9,500원
        2.
        2024.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Ethylene-responsive factors (ERFs) are important plant transcription factors (TFs) that regulate plant responses against various abiotic stresses. However, little information of ERF genes involved in abiotic stress is available in petunia (Petunia ×hybrida). In this study, a petunia ERF gene, PhERF039, was cloned and functional analysis was performed. The quantitative PCR analysis revealed that PhERF039 was induced at the early stage of water deficit stress. Under-expression of PhERF039 (UE) exhibited rosette growth habit, higher number of branches, and delayed flowering compared to the wild type (WT). The UE petunia was evaluated under various volumetric water contents (θ): 0.25, 0.15, 0.10, or 0.05 m3·m-3 using an automated irrigation system. Transgenic plants did not delay plant wilting, but the θ for UE reached to the set point later than that for WT. A lower stomatal conductance was observed in UE than WT under all treatments. These results suggested that PhERF039 could be involved in plant responses under water deficit by regulating stomatal movements as well as branching pattern and flower development.
        4,600원
        3.
        2024.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Platelet-derived growth factor receptor alpha (PDGFRα) is essential for various biological processes, including fetal Leydig cell differentiation. The PDGFRαEGFP mouse model, which expresses an eGFP fusion gene under the native Pdgfrα promoter, serves as a valuable resource for exploring PDGFRα’s expression and function in vivo. This study investigates PDGFRα expression in adult testicular cells using PDGFRαEGFP mouse model. Methods: Genotyping PCR and gel electrophoresis were used to confirm the zygosity of PDGFRαEGFP mice. Histological examination and fluorescence imaging were used to identify PDGFRα expression within testicular tissue. Immunohistochemical analysis assessed the co-expression of PDGFRα with c-Kit, ANO-1, and TASK-1 in testicular cells. Results: Genotyping confirmed the heterozygous status of the mice, which is crucial for studies due to the embryonic lethal phenotype observed in homozygotes. Histological and fluorescence imaging revealed that PDGFRα+ cells were primarily located in the interstitial spaces of the testis, specifically within Leydig cells and peritubular myoid cells (PMCs). Immunohistochemical results showed PDGFRα co-localization with c-Kit and ANO-1 in Leydig cells and a complete co-localization with TASK-1 in both Leydig cells and PMCs. Conclusions: The findings demonstrate specific expression of PDGFRα in Leydig cells and PMCs in adult testicular tissue. The co-expression of PDGFRα with c-Kit, ANO-1, and TASK-1 suggests complex regulatory mechanisms, possibly influencing testicular function and broader physiological processes.
        4,000원
        6.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this paper, in order to study the relationship between the safety culture of highway management agencies and disaster reduction activities (BCMS), a measurement tool was identified through previous research on safety culture, and the validity of the measurement tool was confirmed through exploratory factor analysis. I want to check. The subjects of the study were workers belonging to disaster reduction activity management system certification organizations among highway management organizations. The highway management agencies are the Korea Expressway Corporation, which manages the functional continuity of national highways nationwide, and 8 of the 21 private road agencies that manage the functional continuity of the highways. The safety culture measurement tool is an indicator that measures safety culture factors, and is reorganized by the researcher based on survey items from previous studies, with management/manager safety values and attitudes, safety communication, safety education and training, and safety regulations/ management system as subfactors. A total of 24 questions were comprised of the survey tool. As a result of the study, the result of exploratory factor analysis was that the safety culture scale was extracted into four factors based on theoretical grounds, and the total cumulative variance was 80.360%. When checking the questions for each factor, it was found that all the questions loaded on the factor that was originally intended to be measured. Factor 1 is management, factor 2 is safety, and factor 3 is communication., Factor 4 was named education. Number of questions: 4 management questions, 3 safety questions, communication It consisted of 4 questions and 2 education questions.
        4,000원
        7.
        2023.10 구독 인증기관·개인회원 무료
        2022년 3월12일 제천시의 발표(구체화)에 따르면 제천지역 내 양봉 농가를 대상으로 꿀벌생육실태를 확인한 결과 전체 벌통에서 절반 수준의 꿀벌이 사라진 것을 확인하였다. 이는 이전부터 국내 남부에서 진행되어 오던 꿀벌집단실종 현상의 한계선이 지구온난화로 인해 북쪽으로 이동하고 있다고 언론에서 집중 조명된 적이 있다. 이러한 현상이 과연 한반도 온난화에 의한 것인지의 여부를 파악하고자 원인분석 및 실험을 진행하였다. 먼저 꿀벌실종이 일어난 연도와 달을 중심으로 제천지역내의 기온, 일교차, 강수, 일조량 등 다양한 환경조건 중 예전 과 비교하여 급격한 변화가 일어난 요인을 조사하였으며 이러한 급격한 변화가 일어나는 요인이 꿀벌의 집단실 종에 미칠 수 있는 가능성을 분석하였다. 다른 요인분석으로 미국, 유럽 등에서 꿀벌실종의 주요 원인으로 주목받 고 있는 네오니코티노이드계(Neonicotinoids) 살충제를 이용해 꿀벌에 미치는 영향을 실험하였으며, 생존한계 농도를 측정하였다. 또한 국내 살충제의 연도별 사용량을 간접 비교함으로써 꿀벌실종의 주요요인을 찾고자 하였다. 분석결과 충북제천 꿀벌의 실종은 기온의 상승보다는 일조량이 큰 영향을 미친 것으로 보이며, 향후 일조량에 따른 벌집내부의 온도변화 및 꿀벌의 활동성 변화에 초점을 맞추어 꿀벌실종에 대한 장기적인 상관관 계를 살펴보아야 할 것으로 생각된다.
        9.
        2023.01 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In Korea, most nuclear power plants were designed based on the design response spectrum of Regulatory Guide 1.60 of the NRC. However, in the case of earthquakes occurring in the country, the characteristics of seismic motions in Korea and the design response spectrum differed. The seismic motion in Korea had a higher spectral acceleration in the high-frequency range compared to the design response spectrum. The seismic capacity may be reduced when evaluating the seismic performance of the equipment with high-frequency earthquakes compared with what is evaluated by the design response spectrum for the equipment with a high natural frequency. Therefore, EPRI proposed the inelastic energy absorption factor for the equipment anchorage. In this study, the seismic performance of welding anchorage was evaluated by considering domestic seismic characteristics and EPRI's inelastic energy absorption factor. In order to reflect the characteristics of domestic earthquakes, the uniform hazard response spectrum (UHRS) of Uljin was used. Moreover, the seismic performance of the equipment was evaluated with a design response spectrum of R.G.1.60 and a uniform hazard response spectrum (UHRS) as seismic inputs. As a result, it was confirmed that the seismic performance of the weld anchorage could be increased when the inelastic energy absorption factor is used. Also, a comparative analysis was performed on the seismic capacity of the anchorage of equipment by the welding and the extended bolt.
        4,000원
        10.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The cellular communication network factor (CCN) family proteins regulate many biological events such as angiogenesis, tumor growth, placentation, implantation, and embryogenesis. The expression and function of CCN1, CCN2, and CCN3 at the maternal-conceptus interface are established in humans and rodents, but little is known about the role of CCN4 to CCN6 in the reproductive organs in any other species. Several studies in transcriptome analysis in pigs have shown that the expression of CCN4 and CCN6 increases in the endometrium during early pregnancy. However, their expression, regulation, and function in the endometrium throughout the estrous cycle and pregnancy have not been fully understood in pigs. Thus, we determined the expression, localization, and regulation of CCN4 and CCN6 during the estrous cycle and at the maternal-conceptus interface in pigs. We found that the levels of CCN4, but not CCN6, changed during the estrous cycle. The levels of CCN4 were greater during mid- to late pregnancy than in the early stage, and the levels of CCN6 were greatest on Day 15 of pregnancy. CCN4 and CCN6 were detected in conceptus tissues during early pregnancy and in chorioallantoic tissues during the later stage of pregnancy. CCN4 mRNA was mainly localized to epithelial cells, CCN6 mRNAs to epithelial and stromal cells in the endometrium. In endometrial explant cultures, CCN4 expression was increased by progesterone, and CCN6 expression by interferon-γ. These results suggest that CCN4 and CCN6 may play roles in the establishment and maintenance of pregnancy by regulating the endometrial epithelial cell functions in pigs.
        4,200원
        11.
        2022.05 구독 인증기관·개인회원 무료
        RADTRAN is a code that assesses the radiation risk of radioactive material transportation. RADTRAN assumes that the package is a point source or a line source regardless of package type and corrects the external dose rate using a shape factor which depends on the critical dimension of the package. However, the external dose rate calculated using a shape factor may be different from the actual external dose rate. Therefore, it is necessary to analyze the effect of the shape factor on the external dose rate. In this study, the effect of the shape factor on the external dose rate in RADTRAN was analyzed by comparison with MCNP. This study analyzed change in external dose rate depending on the distance from the package and the critical dimension. The distance from the package was in the range of 1–800 m. The shape of the package was assumed to be cylindrical with a radius of 1 m, and the critical dimensions of the package were assumed to be 2, 4, and 8 m. Attenuation and build-up in the air were not considered to consider only the effect on the shape factor. When simulating the exposure situation using MCNP, the package was assumed to be a volume source, and flux by distance from the package was calculated using F5 tally. The dose rate at 1 m from the package was normalized to 2 mSv·hr−1. As a result of the analysis, the external dose rates of the package were higher in RADTRAN than in MCNP. For the critical dimension of 2, 4, and 8 m, when the distance from package is 1–10 m, the RADTRAN was 1.83, 4.08, and 5.27 times higher on average than MCNP, respectively. And when the distance from the package was 10–100 m and 100–800 m, RADTRAN was 1.10, 2.02, 3.01 times and 1.04, 1.92, 2.43 times higher than MCNP, respectively. It was found that the larger the distance from the package is and the smaller the critical dimension of the package is, the less conservatively RADTRAN assessed. It is because the shape of the package gets closer to the point source as the distance from the package increases, and the shape factor decreases as the critical dimension of the package decreases. The result of this study can be used as the basis for radiation risk assessment when transporting radioactive materials.
        12.
        2022.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Periodontal disease is a chronic but treatable condition which often does not cause pain during the initial stages of the illness. Lack of awareness of symptoms can delay initiation of treatment and worsen health. The aim of this study was to develop and compare different risk prediction models for periodontal disease using machine learning algorithms. We obtained information on risk factors for periodontal disease from the Korea National Health and Nutrition Examination Survey (KNHANES) dataset. Principal component analysis and an auto-encoder were used to extract data on risk factors for periodontal disease. A synthetic minority oversampling technique algorithm was used to solve the problem of data imbalance. We used a combination of logistic regression analysis, support vector machine (SVM) learning, random forest, and AdaBoost to classify and compare risk prediction models for periodontal disease. In cases where we used principal component analysis (PCA) to extract risk factors, the recall was higher than the feature selection method in the logistic regression and support-vector machine learning models. AdaBoost’s recall was 0.98, showing the highest performance of both feature selection and PCA. The F1 score showed relatively high performance in Ada- Boost, logistic regression, and SVM learning models. By using the risk factors extracted from the research results and the predictive model based on machine learning, it will be able to help in the prevention and diagnosis of periodontal disease, and it will be used to study the relationship with various diseases related to periodontal disease.
        4,300원
        13.
        2022.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This paper aims to propose a new systematic approach to analyze the factor productivity and to investigate those characteristics of factor productivity in operational and managerial perspectives. The Cobb-Douglas production function is adopted to estimate the labor and capital productivity. In estimating those productivities the data of The Research on the Actual Condition of Coastal Fisheries (RACF), especially those of Jeon-Nam Province are used. The statistical analysis of RACF data shows that the characteristics are a little bit different between labor and capital of the operational equipment in the coastal fisheries. The Cobb-Douglas type production function is useful in estimating the factor productivity, especially in case of ‘coastal Stow-net fishery’ even though the limited data is used. However, in case of ‘trap fishery,’ the Cobb-Douglas production function appears to have some limitations in estimation. This implies that estimating the factor productivities in fisheries employing broad perspectives and various methods are needed.
        4,900원
        14.
        2021.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Developed countries that have experienced decline in productivity due to the economic crisis in the past have come to recognize the smart factory as an important means to strengthen the competitiveness of the manufacturing industry due to the increase in labor costs, the avoidance of the manufacturing industry, and the resolution of the shortage of skilled manpower. The necessity of nurturing manpower for self-maintenance was felt through identifying factors for successful smart factory introduction by companies and providing smart factory education. Therefore, the effects of educational satisfaction and operational competency on self-efficacy as a parameter and self-efficacy as a parameter were analyzed using research models and hypotheses to determine whether there was an effect between job satisfaction as a dependent variable. As a result of the analysis, it was found that the mediating effect of self-efficacy and self-efficacy on job satisfaction was found to have significant effects on operational competency and self-efficacy as parameters, as well as educational satisfaction and operational competency. The implication of this study is that continuous education and innovation activities are important in order to increase the business performance of companies, and through this, the manufacturing competitiveness of SMEs can be improved.
        4,000원
        16.
        2020.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Naval weapons systems of the Republic of Korea are acquired through the Defense Planning Management System. Recently, acquisition of some naval ships have been delayed, and the causes of the delays have been recognized as inappropriate project management at the Execution Phase. However, we argue that the delay problem in naval ships acquisition should be approached, with due regard for the entire Defense Planning Management System. That is, We should try to investigate from Planning Phase to those of Programming, Budgeting and Execution Phases. Therefore, in this study, we investigated the actual cases of the delay in naval acquisition at all phases of the Defense Planning Management System. Based on the investigation, we tried to identify the naval ship Acquisition Delay Factors and find out the Weights of those factors. As the next step, we calculated the Influence Measures on the naval missions, including the Cost of Naval Capability Gap derived from the delays in acquisition of naval ships. As a final step, we calculated the Acquisition Delay Measures based on the interrelationship between the Acquisition Delay Factors and the Influence Measures. Then we evaluated and analyzed what the results stand for. Finally, we made suggestions for future improvement. The improvement suggestions we made for preventing delay in acquisition of naval ships in this study are as follows. First, we need a shift in perception. It is necessary to measure the Acquisition Delay Factors in acquiring naval ships and manage them from the Planning Phase. Second, resolution must be concerted efforts. All relevant agencies, not just a few, should work together to resolve the problems of acquisition delay. Third, analysis must be based on the accumulation of data. This allows the elaborating of naval ship Acquisition Delay Factors and Delay Measures. If this research method is applied to other military weapons systems in the future, we may be able to not just identify the Acquisition Delay Factors in acquisition of other military weapons systems, but also pursue improvement in those cases.
        4,200원
        18.
        2020.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : In this study, the causality between smart parking user services and its satisfaction level was analyzed statistically, and a smart parking priority decision model was established in terms of the user side. METHODS :The results of the Daegu Metropolitan City survey for the parking state, parking fee, transfer, convenience of use, facilities, and safety that could influence smart parking user satisfaction were used. A structural equation model in SPSS 26 and AMOS 26 programs that facilitates hypothesis testing and importance factor analysis between observed and latent variables was used. RESULTS : The results demonstrated that the importance factor loading on smart parking user services was in the following order: convenience of use (0.996), parking facilities (0.814), safety (0.803), parking information (0.706), transfer (0.618), and parking fee (0.426). Among them, the parking fee was not quite influential in decision making. CONCLUSIONS : The most influential user service on smart parking information systems was the convenience of use, in which congestion in parking lots and parking time were the most influential variables. The most influential variables were in the following order: in parking facilities, the route design of vehicle flow and size of the parking garage; in safety, the entrance location and the level of wear; in the parking state, the availability of parking space and parking fees; and finally in transfer, the convenience of transfer to other modes and the number of transfer parking lots.
        4,000원
        19.
        2020.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Companies struggle to make their best products with high quality and service at a competitive price in global markets. However, customer needs and requirements keep changing with a variety of situations. Companies that face the changes can not stay the same and make an effort to adapt themselves to new circumstances. They would probably review the overall management system that is currently implementing to improve management efficiency. Among other things, quality might be considered to be a crucial element if they are manufacturing industries to be sustained in global markets. KSA (Korean Standards Association) is a government- affiliated organization under the Ministry of Trade, Infrastructure, and Energy. It is a Korean standards provider for quality and service industry. KSA confers national commendations for organizations, quality circles, artisans, QCEC (Quality Competitive Excellent Company), and the most honorable KNQA (Korean National Quality Award) every year. KSA established KNQA on the basis of Malcom Baldrige National Quality Award, Deming Prize, and European Quality Award. Research on quality awards shows that there are many similarities in the framework. Although KSA summarizes two factors for 13 evaluation indicators in the quality competitive excellent model of QCEC, the categorization is ambiguous to explain them according to earlier studies. We performed a deep analysis of foreign quality awards and background for KNQA and QCEC. We conducted a content analysis of KNQA and QCEC and matched evaluation items that were closely related. We proposed a quality competitiveness model with three factors, Technology, System, and Tools, summarizing 13 evaluation indicators in QCEC. Based on audit data for six years from 2012 to 2017 we carried out a confirmatory factor analysis for the proposed model by examining the model validity and fitness.
        4,200원
        20.
        2020.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A new WRKY transcription factor gene was isolated by ESTs screening from a cDNA library of suspension cultured cells of Sweet potato (Ipomoea batatas). The 2,285 bp cDNA fragment, IbWRKY, was sequenced, from which a 505 amino acid residue protein was deduced. A search of the protein BLAST database identified significant similarity to other plant WRKY31 protein sequences. RT-PCR analysis showed expression patterns of IbWRKY31 in various intact tissues and suspension cultured cells of Sweet potato, and in leaves exposed to different stresses. The IbWRKY31 gene was highly expressed in suspension cultured cells. In leaf tissues, IbWRKY31 showed strong expression during salicylic acid and methyl jasmonate treatments. Expression of IbWRKY31 was also induced under various abiotic stress and pathogen infection conditions, such as wounding, H2O2, MV, PEG, NaCl, and bacterial pathogen infection. These results suggest that IbWRKY31 is involved in plant responses to various stress conditions, such as abiotic stresses and pathogen infection through a defense signaling pathway.
        4,000원
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