• Journal of Korean Academy of Nursing
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• v.49 no.4
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• pp.495-504
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• 2019

Purpose: Nursing students experience a high degree of perceived stress during skills training. The resulting academic sentiment is worthy of research. This study examined the learning motivation as a mediator in the association between perceived stress and positive deactivating academic emotions in nursing students undergoing skills training. Methods: A survey was conducted on 386 third-year undergraduate nursing students at a university in Changchun, China, in 2017. The survey included the items on perceived stress, learning motivation during nursing skill training, and general academic emotion. There were 381 valid responses (response rate=98.7%). Based on the results of partial correlation and stepwise multiple regression equations, the study examined the mediation model between perceived stress, learning motivation and positive-deactivating academic emotions using process 2.16 (a plug-in specifically used to test mediation or moderation effect in SPSS). Results: There was a significant negative correlation between students' perceived stress and learning motivation during nursing skills training and positive-deactivating academic emotions. Nervousness, loss of control, and interest in developing reputation had significant predictive effects on positive-deactivating academic emotions. The mediating model was well supported. Conclusion: Learning motivation during nursing skills training lessened the damage of perceived stress on positive-deactivating academic emotions. Improving students' motivation to learn could reduce their perceived stress and build more positive emotions. Positive emotions during learning played an important role in helping nursing students improve skills and enhance their nursing competence.

• Atmosphere
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• v.29 no.1
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• pp.75-86
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• 2019

In this paper, we introduce a novel Climate & Environment Database System (CEDS). The CEDS is developed by the National Institute of Meteorological Sciences (NIMS) to provide easy and efficient user interfaces and storage management of climate model data, so improves work efficiency. In uploading the data/files, the CEDS provides an option to automatically operate the international standard data conversion (CMORization) and the quality assurance (QA) processes for submission of CMIP6 variable data. This option increases the system performance, removes the user mistakes, and increases the level of reliability as it eliminates user operation for the CMORization and QA processes. The uploaded raw files are saved in a NAS storage and the Cassandra database stores the metadata that will be used for efficient data access and storage management. The Metadata is automatically generated when uploading a file, or by the user inputs. With the Metadata, the CEDS supports effective storage management by categorizing data/files. This effective storage management allows easy and fast data access with a higher level of data reliability when requesting with the simple search words by a novice. Moreover, the CEDS supports parallel and distributed computing for increasing overall system performance and balancing the load. This supports the high level of availability as multiple users can use it at the same time with fast system-response. Additionally, it deduplicates redundant data and reduces storage space.

• Steel and Composite Structures
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• v.44 no.2
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• pp.155-169
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• 2022

In the present paper an analytical model was developed to study the non-linear vibrations of Functionally Graded Carbon Nanotube (FG-CNT) reinforced doubly-curved shallow shells using the Multiple Scales Method (MSM). The nonlinear partial differential equations of motion are based on the FGM shallow shell hypothesis, the non-linear geometric Von-Karman relationships, and the Galerkin method to reduce the partial differential equations associated with simply supported boundary conditions. The novelty of the present model is the simultaneous prediction of the natural frequencies and their mode shapes versus different curvatures (cylindrical, spherical, conical, and plate) and the different types of FG-CNTs. In addition to combining the vibration analysis with optimization algorithms based on the genetic algorithm, a design optimization methode was developed to maximize the natural frequencies. By considering the expression of the non-dimensional frequency as an objective optimization function, a genetic algorithm program was developed by valuing the mechanical properties, the geometric properties and the FG-CNT configuration of shallow double curvature shells. The results obtained show that the curvature, the volume fraction and the types of NTC distribution have considerable effects on the variation of the Dimensionless Fundamental Linear Frequency (DFLF). The frequency response of the shallow shells of the FG-CNTRC showed two types of nonlinear hardening and softening which are strongly influenced by the change in the fundamental vibration mode. In GA optimization, the mechanical properties and geometric properties in the transverse direction, the volume fraction, and types of distribution of CNTs have a considerable effect on the fundamental frequencies of shallow double-curvature shells. Where the difference between optimized and not optimized DFLF can reach 13.26%.

• Journal of Environmental Impact Assessment
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• v.22 no.6
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• pp.591-607
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• 2013

The objectives of the study were to evaluate the aquatic environment of an urban stream using various ecological parameters of biological biomarkers, physical habitat quality and chemical water quality and to develop a "Multimetric Eco-Model" ($M_m$-E Model) for the ecosystem evaluations. For the applications of the $M_m$-E model, three zones including the control zone ($C_Z$) of headwaters, transition zone ($T_Z$) of mid-stream and the impacted zone ($I_Z$) of downstream were designated and analyzed the seasonal variations of the model values. The biomarkers of DNA, based on the comet assay approach of single-cell gel electrophoresis (SCGE), were analyzed using the blood samples of Zacco platypus as a target species, and the parameters were used tail moment, tail DNA(%) and tail length (${\mu}m$) in the bioassay. The damages of DNA were evident in the impacted zone, but not in the control zone. The condition factor ($C_F$) as key indicators of the population evaluation indicator was analyzed along with the weight-length relation and individual abnormality. The four metrics of Qualitative Habitat Evaluation Index (QHEI) were added for the evaluations of physical habitat. In addition, the parameters of chemical water quality were used as eutrophic indicators of nitrogen (N) and phosphorus (P), chemical oxygen demand (COD) and conductivity. Overall, our results suggested that attributes of biomarkers and bioindicators in the impacted zone ($I_Z$) had sensitive response largely to the chemical stress (eutrophic indicators) and also partially to physical habitat quality, compared to the those in the control zone.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.569-577
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• 2023

This study selected seven carbon-neutral villages, considering the characteristics of each region, including all five administrative districts of Changwon City, and proposed activation plans based on business evaluations through surveys of local residents and FGIs with leaders. The analysis showed that carbon-neutral education was the most important factor for activating carbon-neutral villages, with a response rate of 91.9% for 17 multiple-choice questions, followed by legal (ordinance) arrangements at 79.3% and village organization building at 74.1%. Based on this, the following activation plans through the participation of residents who are involved in the project of creating a carbon-neutral village in Changwon City were proposed. First, the characteristics of each carbon-neutral village model were classified into a resource circulation-based model, an environmental creation-based model, an environmental education and experience event-based model, and an energy efficiency-based model. Second, it is necessary to create and present carbon-neutral village growth stage guidelines for the growth of carbon-neutral villages. Third, manuals and teaching materials related to carbon neutrality, such as theories, issues, and practices, need to be produced and distributed for leaders and activists to easily apply and access for self-government operation of the village. Finally, if a carbon-neutral support center that is legally installable in Changwon City is established, it is expected that the lives of local residents will become more sustainable for carbon-neutral living in preparation for climate crises.

• Journal of the Korean Society of Earth Science Education
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• v.11 no.2
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• pp.125-144
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• 2018

The purpose of this study is to analyze the astronomical thinking level of elementary, middle, and high school students using ordered multiple choice items. For this purpose, we constructed a questionnaire comprising three items about spatial thinking and system thinking. This survey was conducted and applied to 1,066 students in the 5th grade, 8th grade, and 11th grade in 12 schools located in Gangwon Province. The collected student response data were analyzed by applying inferential statistics of classical test theory and Rasch model. The results of the analysis were as follows; First, in the level of spatial thinking, students were able to grasp the spatial location and orientation of the celestial body, but were not able to convert the celestial motion of two-dimensional plane into three-dimensional plane, and it was revealed that there is no statistically significant difference in the spatial thinking of students among grade levels. Second, in the level of system thinking, students were able to identify the components and relationship between components of the celestial motion system, but could not identify the patterns of the system, and it was revealed that there was statistically significant difference among the system thinking of students in different grade levels, unlike in spatial thinking. Third, the astronomical thinking expressed in certain context (content) was very similar regardless of grade level, Through this, we could confirm the context-dependency or content-dependency of the astronomical thinking of students. It is expected that the results of this study can be used as basic data for exploring ways to enhance astronomical thinking level in school science classes.

• Journal of Distribution Science
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• v.11 no.2
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• pp.71-81
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• 2013

Purpose - The TOEIC test has been leading the change in the quality and the globalization of companies for about last 30 years. The TOEIC test is taken by about two million people each year and is used as a criterion to select new employees in companies or government offices, for performance ratings, and for overseas posting selections. Universities also use TOEIC test in various ways. Since the TOEIC test is used for the selection of new students for admission, transferring extra credits, scholarships, graduation certification, and admission of international students studying abroad, many universities all over the country provide students with TOEIC study lectures through their own language institutes. Despite the fact, there has been no research on the service quality or even the current situation of these institutes. Thus, this study aims to evaluate the factors that impact TOEIC lecture service quality and analyzes the effect of the expectation related to the education service quality and the result of education on intentional behavior. Research design, data, methodology - Data was collected by administering a survey to current TOEIC students from different university language institutes. The survey questionnaire comprised of a five-point Likert scale. The demographic analysis was conducted using the frequency analysis method and the factor analysis was conducted to verify the validity of questionnaire over any variable. The reliability analysis was conducted to verify the reliability of the results. Besides, multiple regression analysis, regression analysis, and mediated effect verification were also conducted. For education service quality, four different independent variables such as reliability, response, conviction, and sympathy were considered using the SERVQUAL survey model. Based on the research models, the study hypotheses below were formulated in order to recognize an effect relationship between the variables. The four hypotheses are, "the hypothesis on education service quality and TOEIC study result expectation," "the hypothesis on education service quality and behavioral intention," "the hypothesis on study result expectation and behavioral intention," and "the hypothesis on study result expectation and mediated effect." Results - The results are as follows. First, the factors like response, conviction, and sympathy have a positive influence on TOEIC study result expectations. Second, the TOEIC study result expectation has a positive influence on the factors of behavioral intention such as re-sign up, positive word-of-mouth, "loyalty towards school." Third, it was verified that the mediated effect on behavioral intention was influenced by education service quality at university foreign language institute, while the study result expectation has only a partial mediated effect. Conclusions - The implications of this study are summarized as follows: First, it suggests a new research model for the effect of the expectation related to the education service quality and the result of education in the university language institutes on the behavioral intention. Second, it has established a relationship between the education service quality and study result expectation by verifying the mediated effect on them.

• Journal of Ginseng Research
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• v.44 no.4
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• pp.580-592
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• 2020

Background: Radix et Rhizoma Ginseng (thereafter called ginseng) has been used as a medicinal herb for thousands of years to maintain people's physical vitality and is also a non-organ-specific cancer preventive and therapeutic traditional medicine in several epidemiologic and preclinical studies. Owing to few toxic side effects and strong enhancement on body immunity, ginseng has admirable application potential and value in cancer chemoprevention. The study aims at investigating the chemopreventive effects of ginseng on cutaneous carcinoma and the underlying mechanisms. Methods: The mouse skin cancer model was induced by 7,12-dimethylbenz[a]anthracene/12-O-tetradecanoylphorbol-13-acetate. Ultraperformance liquid chromatography/mass spectrometry was used for identifying various ginsenosides, the main active ingredients of ginseng. Comprehensive approaches (including network pharmacology, bioinformatics, and experimental verification) were used to explore the potential targets of ginseng. Results: Ginseng treatment inhibited cutaneous carcinoma in terms of initiation and promotion. The content of Rb1, Rb2, Rc, and Rd ginsenosides was the highest in both mouse blood and skin tissues. Ginseng and its active components well maintained the redox homeostasis and modulated the immune response in the model. Specifically, ginseng treatment inhibited the initiation of skin cancer by enhancing T-cell-mediated immune response through upregulating HSP27 expression and inhibited the promotion of skin cancer by maintaining cellular redox homeostasis through promoting nuclear translocation of Nrf2. Conclusion: According to the study results, ginseng can be potentially used for cutaneous carcinoma as a chemopreventive agent by enhancing cell-mediated immunity and maintaining redox homeostasis with multiple components, targets, and links.

• Journal of Korean Society of Transportation
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• v.22 no.6
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• pp.133-144
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• 2004

A model and a measure which can evaluate the risk of rear end collision are developed. Most traffic accidents involve multiple causes such as the human factor, the vehicle factor, and the highway element at any given time. Thus, these factors should be considered in analyzing the risk of an accident and in developing safety models. Although most risky situations and accidents on the roads result from the poor response of a driver to various stimuli, many researchers have modeled the risk or accident by analyzing only the stimuli without considering the response of a driver. Hence, the reliabilities of those models turned out to be low. Thus in developing the model behaviors of a driver, such as reaction time and deceleration rate, are considered. In the past, most studies tried to analyze the relationships between a risk and an accident directly but they, due to the difficulty of finding out the directional relationships between these factors, developed a model by considering these factors, developed a model by considering indirect factors such as volume, speed, etc. However, if the relationships between risk and accidents are looked into in detail, it can be seen that they are linked by the behaviors of a driver, and depending on drivers the risk as it is on the road-vehicle system may be ignored or call drivers' attention. Therefore, an accident depends on how a driver handles risk, so that the more related risk to and accident occurrence is not the risk itself but the risk responded by a driver. Thus, in this study, the behaviors of a driver are considered in the model and to reflect these behaviors three concepts related to accidents are introduced. And safe stopping distance and accident occurrence probability were used for better understanding and for more reliable modeling of the risk. The index which can represent the risk is also developed based on measures used in evaluating noise level, and for the risk comparison between various situations, the equivalent risk level, considering the intensity and duration time, is developed by means of the weighted average. Validation is performed with field surveys on the expressway of Seoul, and the test vehicle was made to collect the traffic flow data, such as deceleration rate, speed and spacing. Based on this data, the risk by section, lane and traffic flow conditions are evaluated and compared with the accident data and traffic conditions. The evaluated risk level corresponds closely to the patterns of actual traffic conditions and counts of accident. The model and the method developed in this study can be applied to various fields, such as safety test of traffic flow, establishment of operation & management strategy for reliable traffic flow, and the safety test for the control algorithm in the advanced safety vehicles and many others.

• Journal of the Korean Ceramic Society
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• v.49 no.5
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• pp.475-483
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• 2012

High capacitance X5R MLCCs based on $BaTiO_3$ ceramic dielectric layers exhibit a single broad, asymmetric arc shape impedance and modulus response over the wide frequency range between 1 MHz to 0.01 Hz. Analysis according to the conventional brick-layer model for polycrystalline conductors employing a series connection of multiple RC parallel circuits leads to parameters associated with large errors and of little physical significance. A new parametric impedance model is shown to satisfactorily describe the experimental spectra, which is a parallel network of one resistor R representing the DC conductivity thermally activated by 1.32 eV, one ideal capacitor C exactly representing bulk capacitance, and a constant phase element (CPE) Q with complex capacitance $A(i{\omega})^{{\alpha}-1}$ with ${\alpha}$ close to 2/3 and A thermally activated by 0.45 eV or ca. 1/3 of activation energy of DC conductivity. The feature strongly indicate the CK1 model by J. R. Macdonald, where the CPE with 2/3 power-law exponent represents the polarization effects originating from mobile charge carriers. The CPE term is suggested to be directly related to the trapping of the electronic charge carriers and indirectly related to the ionic defects responsible for the insulation resistance degradation.