• International Journal of Computer Science & Network Security
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• v.23 no.5
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• pp.121-127
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• 2023

A 500 km/h linear motor high speed terrestrial transportation service is planned to launch 2027 in Japan. In order to support 5G service in the train, the Sub-carrier spacing frequency of 30 kHz is planned to be used instead of common 15 kHz sub-carrier spacing to mitigate Doppler effect in such high-speed transportation. In addition, to increase the cell size of 5G mobile system, plural Base Station antenna will transmit the identical Down Link (DL) signal to form the expanded cell size along the train rail. In this situation, forward and backward antenna signals will be Doppler shifted by reverse direction respectively and the receiver in the train might suffer to estimate accurate Channel Transfer Function (CTF) for its demodulation. In this paper, Delay and Doppler Profiler (DDP) based Channel Estimator is proposed and it is successfully implemented in signal processing simulation system. Then the simulated performances are compared with the conventional Time domain linear interpolated estimator. According to the simulation results, QPSK modulation can be used even under severe channel condition such as 500 km/h, 2 path reverse Doppler Shift condition, although QPSK modulation can be used less than 200 km/h with conventional Channel estimator.

• Korean Journal of Human Ecology
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• v.8 no.2
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• pp.227-243
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• 1999

The purpose of this study was to analyze a causal relations of children's learned helplessness, stress, perception of self-competence and mother's childrearing attitudes. The subjects were 370 of 4th and 6th grade in elementary school and the second grade in junior high school in Busan and their's mothers. The instruments used for this study were learned helplessness scale, stress scale, self-perception profile for children, and childrearing attitude scale. The data was analyzed with pearson's correlation, multiple regression and path analysis. The major findings of this study were as follows : 1. Children's global self-worth, social self, age and mother's controlling childrearing attitudes predicted children's stress. 21% of the variance of children's stress was explained by these variables. 2. Children's stress, global self-worth, academic and social self predicted children's learned helplessness. 54% of the variance of children's learned helplessness was explained by these variables. 3. 1) Global self-worth was the first contribution and had a indirect effect through stress as well as a direct effect on children's learned helplessness. 2) Children's stress and academic self had direct effect on children's learned helplessness. 3) Children's social self had a indirect effect through stress as well as a direct effect on children's learned helplessness. 4) Mother's affectionate childrearing attitudes had indirect effect through academic, and social self and global self-worth on children's learned helplessness. Mother's controlling childrearing attitudes had indirect effect through stress on children's learned helplessness. Children's age had a indirect effect through global self-worth and stress and children's sex had a indirect effect through social self on children's learned helplessness.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.8
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• pp.200-209
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• 2017

This study examined the mediating effect of depression on the relationship between over-control parenting styles and mobile phone dependency among children. The 5th-year longitudinal data from the Korean Children & Youth Panel Survey (KCYPS) were collected from 4th grade elementary school students. The data were analyzed by the structural equation modeling and bootstrapping. The results of this study were as follows. First, there is a positive path from over-control parenting styles to depression, from depression to mobile phone dependency, and from over-control parenting styles to mobile phone dependency. Second, depression had a mediating effect on the association between over-control parenting styles and mobile phone dependency. Based on these results, more study of elementary school students' reliance on cell phones is needed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4368-4379
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• 2013

Purpose: The purpose of this study was to identify the factors that influence verbal abuse in early childhood mothers and to examine the fitness of a path model among these variables. The goal of the study was to provide fundamental data on ways in which verbal abuse by early childhood mothers can be prevented. Methods: The data was collected by using self report questionnaires from December 7th to 25th, 2011. The subjects were 320 early childhood mothers who had children in kindergarten. In order to estimate the hypothesized model, the data was analyzed using the AMOS 18.0 programs for structural equation modeling. Results: Parenting stress, anger and anger expression demonstrated a direct effect on causing verbal abuse by early childhood mothers. This study suggest that parental education program are necessary which a early childhood mothers can be express positively about parenting stress and anger.

• Transactions of Materials Processing
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• v.31 no.6
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• pp.351-364
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• 2022

The yield criterion, or called yield function, plays an important role in the study of plastic working of a sheet because it governs the plastic deformation properties of the sheet during plastic forming process. In this paper, we propose a modified version of previous anisotropic yield function (Trans. Mater. Process., 31(4) 2022, pp. 214-228) based on J2 and J3 stress invariants. The proposed anisotropic yield model has the 6th-order of stress components. The modified version of the anisotropic yield function in this study is as follows. f(J₂⁰,J₃⁰) ≡ (J₂⁰)³ + α(J₃⁰)² + β(J₂⁰)^3/2 × (J₃⁰) = k⁶ The proposed anisotropic yield function well explains the anisotropic plastic behavior of various sheets such as aluminum, high strength steel, magnesium alloy sheets etc. by introducing the parameters α and β, and also exhibits both symmetrical and asymmetrical yield surfaces. The parameters included in the proposed model are determined through an optimization algorithm from uniaxial and biaxial experimental data under proportional loading path. In this study, the validity of the proposed anisotropic yield function was verified by comparing the yield surface shape, normalized uniaxial yield stress value, and Lankford's anisotropic coefficient R-value derived with the experimental results. Application for the proposed anisotropic yield function to AA6016-T4 aluminum and DP980 sheets shows symmetrical yielding behavior and to AZ31B magnesium shows asymmetric yielding behavior, it was shown that the yield locus and yielding behavior of various types of sheet materials can be predicted reasonably by using the proposed anisotropic yield function.

• Journal of Distribution Science
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• v.15 no.1
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• pp.95-104
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• 2017

Purpose - This study focuses on long-term orientation that can lead long-term partnership. A long-term orientation needs a trust and relation commitment between company. So in this study, the researcher conducts a dependent variable as a justice recognition and brand asset value to research model to find out casual relationship among quoted factors. Research design, data, and methodology - The focus of this study was employees who work in a liquor distribution company to figure out factors that effect on long-term relationship in b2b transaction. The development of the research model is based on the literature of the preceding research analysis of justice recognition, brand asset value, trust, relation commitment and long-term orientation. This study have constructs that defined operationally by previous studies, research model design that to figuring casual relationships among the quoted factors. From 2016 Sep. 1st to Oct. 30th, a questionnaire survey was conducted targeting employees who work in liquor distribution company. 176 survey data were used for empirical analysis to prove the research hypotheses. Results - The main results of this study's empirical methodology were as follows. First, procedural justice and interactive justice has a positive significant effect on trust and relation commitment. Also brand image, brand awareness and perceived quality has a positive significant effect on trust and relation commitment. Second, trust and relation commitment has a positive significant effect on long-term orientation. Every hypothesis adopted as the researcher designed for empirical study. Conclusions - Based on empirical results, this study confirmed that trust and relation commitment has empirical relationship with long-term orientation. Based on the analysis, the researcher provided managerial implication by setting 2 way path for making long-term orientation with business company. First path is procedural justice to relation commitment. It contains that procedural justice recognised while business transaction execution, consideration intension and relation development will happen in b2b. Second path is perceived quality to trust. It contains that the perceived quality recognised while business transaction execution, trust will increase rapidly. So when a business company wants to make a partnership, they have to consider procedural justice and perceived quality to make a long-term relationship.

• Korean Journal of Child Studies
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• v.37 no.2
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• pp.13-25
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• 2016

Objective: The purposes of this study were to examine the effects of school-age children's ego strength, failure tolerance, and performance anxiety on their school class adjustment, and to model the relation structure of the variables. Method: For these purposes, a questionnaire survey was conducted with 562 6th graders. Results and Conclusion: The results of this study are summarized as follows. First, ego strength, failure tolerance, and performance anxiety were significantly different according to gender. Second, in male students, ego strength, failure tolerance, and performance anxiety had a significant direct effect on school class adjustment. In addition, ego strength and failure tolerance had a significant indirect effect on school class adjustment. Third, female students' paths to school class adjustment were similar to male students' but the effect of failure tolerance on performance anxiety and the effect of performance anxiety on school class adjustment were not significant. Fourth, in the results of multi-group analysis, the effect path from ego strength to school class adjustment was different between male and female students, and the effect was higher in female students than in male students.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.5
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• pp.331-337
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• 2017

Thermal batteries, reserve power source, is activated by melting of molten salt at the temperature range of $350{\sim}550^{\circ}C$. To immobile the molten state electrolyte when the thermal battery is activated, the binder must be added in electrolyte. Usually, molten salts include 30~40 wt% of MgO binder to ensure electrical insulation as well as safety. However, the conventional MgO binder tends to increase ionic conductive resistance and thus the inclusion of the binder increases the total impedance of the battery. This paper mainly focused on the study of yttria stabilized zirconia (YSZ) as an alternative binder for molten salt. The chemical stability between the molten salt and YSZ is measured by XRD and DSC. And the sufficient path for ionic conduction on molten salt could be confirmed by the enhanced wetting behavior and the enlarged pore size of YSZ. The electrochemical properties were analyzed using single cell tests so that it showed the outstanding performance than that using MgO binder.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.6
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• pp.532-539
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• 2001

In robot teleoperation, much research has been carried out to control the slave robot from remote site. One of the essential devices for robot teleoperation is the masterarm, which is a path command generating device worn on human arm. In this paper, a new masterarm based on human kinematics is proposed. Its controller is based on the distributed controller architecture composed of two controller parts: a host controller and a set of satellite controllers. Each satellite controller measures the corresponding joint angle, while the host controller performs forward and inverse kinematics calculation. This distributed controller architecture can make the data updating faster, which allows to implement real-time implementation. The host controller and the satellited controllers are networked via three-wire daisy-chained SPI(Serial Peripheral Interface) protocol, so this architecture makes the electrical wiring very simple, and enhances maintenance. Analytical method for finding three additional unknown joint angles is derived using only three measured angles for each shoulder and wrist, which makes th hardware implementation very simple by minimizing the required number of satellite controllers. Finally, the simulation and experiment results are given to demonstrate the usefulness and performance of the proposed masterarm.

• East Asian Journal of Business Economics (EAJBE)
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• v.8 no.3
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• pp.25-36
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• 2020

Purpose - As the interest of financial aria increase in economic change and labor market change, this study focused on the employee of the financial aria in Korea. The purpose of this study is to analyses relation among relationship variable and organizational culture variable and organizational effectiveness of financial aria employees in Korea. Research design, data, and methodology - This study measured relationship variable with communication and trust. And measured organizational culture variable with innovation, relation, hierarchy and rational. And measured organizational effectiveness with job satisfaction and organizational commitment. Empirical analysis is conducted using 442 financial aria employees of 7th HCCP in KRIVET. And SPSS is used in frequency and stepwise regression test and AMOS is used in path analysis with group differentiation test. Results - Overall results show that trust and relation culture give positive influence on job satisfaction. Organizational commitment results show that relation culture and rational culture give positive influence and also job satisfaction. However, hierarchy culture gives negative influence on organizational commitment. Also, the moderating effect of work characteristics is significant. Conclusions -Result of this study give managerial implication to HRM and also expend inflected organizational culture study to financial aria in Korea. Especially gives insight to relationship, organizational culture and organizational effectiveness. And management differentiation needs between work characteristic.