• Journal of Power System Engineering
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• v.14 no.3
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• pp.33-38
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• 2010

Technology of vehicle industry has been developing and it is required a better vehicle performance than before. Therefore, the consumers are asking not only an economic efficiency, functionality, polished design, ride comfort and silence but also a driving stability. The ride comfort, silence and driving stability are influenced by the size of vehicle and various facilities. But the principal factor is a room noise and vibration sensed by a driver and passenger. Thus, the NVH of vehicle has been raised and used as a principal factor for evaluation of vehicle performance. The primary objective of this study is an optimized design of powertrain mounting system. To optimized design was applied MSC.Nastran optimization modules. Results of dynamic analysis for powertrain mounting system was investigated. By theses results, design variables was applied 12 dynamic spring constant. And the weighting factor according to translational displacement and rotational displacement applied 3 cases. The objective function was applied to minimize displacement of powertrain. And the design variable constraint was imposed dynamic spring constant ratio. The constraint of design variable for objective function was imposed bounce displacement for powertrain.

• Journal of Information Technology Services
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• v.12 no.2
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• pp.231-242
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• 2013

E-commerce market has been increasing rapidly, which reflects the convenience and economic benefits associated with its usage. Unlike the traditional markets, WOM (Word-of-Mouth) becomes more important because e-commerce consumers can't experience the real product in the purchase decision-making process. In this regard, identifying the influencing factors to WOM of internet e-commerce site is very important. In this paper, we aim to examine the effects of perceived and individual variables on WOM in the context of internet e-commerce site. In order to analyze the antecedents, we selected perceived and individual factors such as regret tendency scale, prior knowledge and merchandise attractiveness. In addition, we examined the role of gender as dummy and moderating variable. For empirical analysis, we surveyed real users of internet e-commerce site. As a result, all antecedents showed significant influence on WOM except regret tendency scale. Among the variables, the merchandise attractiveness has top standardized coefficient. Gender plays a role as moderating variable when only interacting with regret tendency scale. The results of this research can be useful guidelines for internet e-commerce providers.

• Journal of Power Electronics
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• v.15 no.2
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• pp.487-496
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• 2015

In order to ensure that photovoltaic (PV) systems work at the maximum power point (MPP) and maximize the economic benefits, maximum power point tracking (MPPT) techniques are normally applied to these systems. One of the most widely applied MPPT methods is the incremental conductance (INC) method. However, the choice of the step size still remains controversial. This paper presents an improved variable step size INC MPPT algorithm that uses four different step sizes. This method has the advantages of INC but with the ability to validly adjust the step size to adapt to changes of the PV's power curve. The presented algorithm also simultaneously achieves increased rapidity and accuracy when compared with the conventional fixed step size INC MPPT algorithm. In addition, the theoretical derivation and specific applications of the proposed algorithm are presented here. This method is validated by simulation and experimental results.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.201-211
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• 2021

This study aims to analyze the determinants of macroeconomic and institutional stability on the development of the global sukuk market by controlling the effects of population. This study uses panel data namely GDP per-capita, exchange rate, and inflation as the proxies for macroeconomic stability sourced from the World Development Index, and six dimensions of Worldwide Governance Indicators (WGI) as institutional proxies sourced from WGI-World Bank. To make robust the relationship between macroeconomics and institutional on the global sukuk market, the population (POP) variable was included as a control variable. The development of sukuk uses a proxy for sukuk issuance in the International Islamic Financial Market, for the annual period from 2002-2017. The data was analyzed using the General Method of Moment, and the results show that by controlling the population effects that proved to be significant, GDP per-capita and the rule of law have a significant impact on the development of sukuk, especially when incorporating population effects as control variables, whereby further ascertaining the effect of each macroeconomic-stability variable and institutional stability on sukuk development, especially inflation, found not to affect sukuk development. These results also confirm the previous findings, whereby inflation remains controllable at a certain level for economic development.

• Asia-Pacific Journal of Business
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• v.11 no.2
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• pp.27-43
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• 2020

Purpose - This study explores the impact of the real estate industry on related industries for the perspective of Chinese steel companies. Design/methodology/approach - The impact of housing prices on the 41 listed steel companies' performance was analyzed by using the panel data model. We used two kinds of housing price indexes that are set in the panel data models to estimate the range of the real estate market, driving the performance growth of steel listed companies. Moreover, the net profit of steel companies is used as the dependent variable. To test the stability of the model, ROA used as a dependent variable for the robustness test. Also, to avoid the time trend of housing prices, this paper selects the growth rate of housing prices as the primary research variable. After Fisher-type testings, there is no unit root problem in both independent and dependent variables. Findings - The results indicated that the rise in the housing price has a positive influence on the steel company performance. When the housing price increases by 1%, the net profit of steel enterprises will increase by 5 to 20 million yuan. Research implications or Originality - In this paper, empirical data at the micro-level and panel model are used to quantify China's real estate industry's driving effect on the iron and steel industry, providing evidence from the microdata level. It helps us to understand further the status and role of China's real estate industry in the economic structure.

• Journal of the Korea Fashion and Costume Design Association
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• v.24 no.4
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• pp.135-152
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• 2022

Recent weddings have been performed in more unique and characterful styles going beyond the existing same old method of past weddings, and they are changed into small weddings with simplified style without unnecessary procedures by choosing a wedding venue different from others. It is necessary to develop a new wedding dress design suitable for such changing wedding culture, and especially, dresses are required to have some practical designs, so that they can be worn not only for the wedding ceremony or party but also for everyday life. Therefore, the purpose of this study is to develop a new normal wedding dress for small weddings that reflect design according to the emerging small wedding culture. To this end, a theoretical review of small weddings was conducted, and based on this, a new normal wedding dress design was developed for small weddings. Based on practicality and economic feasibility, the New Normal Wedding Dress exhibited 'variable by wearing method' that changes according to the wearer's purpose and 'variable by attaching and detaching method' that changes according to the detachment of details. The small wedding dress developed through this study is expected to become a new standard for wedding dresses that is suitable for the changing wedding culture.

• Journal of Distribution Science
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• v.20 no.4
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• pp.95-100
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• 2022

Purpose: This study aimed to investigate whether distribution and service companies maintained their accounting information quality and provided reliable information despite the economic changes occurring after the outbreak of the COVID-19 pandemic in Korea. The distribution industry has enjoyed increased demand as many companies expanded their untact distribution channels, including to online sales. However, as the pandemic drags on, their future prospects remain uncertain. Research design, data, and methodology: In this study, we define 2018-2019 as the "pre COVID-19 period" and 2020 as the "post COVID-19 period." An empirical analysis was performed using a regression model that includes POST, the independent variable, indicating the post COVID-19 period, and discretionary accruals(DA), a proxy for earnings management, as a dependent variable. Results: The analysis shows that the coefficient of POST is significantly positive (+) for the dependent variable DA. This finding suggests that distribution and service companies engaged in more earnings management during the post COVID-19 period than during the pre COVID-19 period, indicating their awareness of the uncertainty of future business performance as the pandemic persists. An additional analysis confirmed that smaller companies with fewer stakeholders and higher information asymmetry tend to engage more in earnings management than larger companies.

• Journal of Digital Convergence
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• v.11 no.2
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• pp.175-182
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• 2013

In this paper, the simulation model of house price is presented on the basis of pricing mechanism between the demand and the supply of apartments in seoul. The algorithm of house price simulation model for calculating the rate of price over time includes feedback control theory. The feedback control theory consists of stock variable, flow variable, auxiliary variable and constant variable. We suggest that the future price of apartment is simulated using mutual interaction variables which are demand, supply, price and parameters among them. In this paper we considers three items which include the behavior of apartment price index, the size of demand and supply, and the forecasting of the apartment price in the future economic scenarios. The proposed price simulation model could be used in public needs for developing a house price regulation policy using financial and non-financial aids. And the quantitative simulation model is to be applied in practice with more specific real data and Powersim Software modeling tool.

• Fire Science and Engineering
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• v.22 no.2
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• pp.9-19
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• 2008

Recently the systematic change in the fire and disaster prevention administration, which was less studied than other administrative systems, has been in progress. In particular, the fire service demands are increasing and forms are diversified. The first thing you must do is to make up the fire service power according to the fire service demands. Such an allocation results in social welfare satisfaction. The purpose of this study is to investigate the determinants of fire service force. And this study investigates that fire service demand is affected by socioeconomic factor. To do this, this study reviews fire service force, the fire service demand, socioeconomic factor and financial factor. And this study sets up four hypotheses based on the theoretical backgrounds and the past research. The statistical method used for the verification of hypotheses are multiple regression analysis and structural equitation analysis. The analysis showed that fire service demand and financial factor were positive significant variable for fire service power. But socioeconomic factor was a negative significant variable. Also the analysis showed that social factor was a positive significant variable and economic factor was a negative significant variable for fire service demand.

• The Mathematical Education
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• v.24 no.2
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• pp.74-104
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• 1986

This study aims at investigating the correlation between such variables as a child's family circumstance and personality and that of the child's mathematical ability. For the objects of the study five hundreds and sixteen students (male 273, female 243) were andomly selected from the fifth grade primary school students in the city of Seoul. For the tool of measure the investigation of Korean family circumstances with particular characteristics, the personality test by Chong Pom Mo and Kim Ho Kwon, and the intelligence test by Lee Sang Ro, Chin Whal Kyo and Pyon Chang Jin were employed. For the statistical analysis S. A. S. C., the statistical analysis package of KAIST was employed. The resutis of the test can be summarized as follows. The correlation between the variable of family Circumstance and that of mathematical alility 1) In case of the significance level 0.05 the education of the childs mother and the order of the child's birth have much to do with the perception speed. In case of the significance level 0.1 it makes some difference in the child's perception spead whether the clild's mother has a job or not. 2) In case of the significance level 0.05 the education of the child's father and mother, the father's job and the type of habitation have influence on the child's perception of space. 3) In case of the significance level 0.05 the education of the child's father and mother, the father's job, the order of the child's birth, the type of habitation, their religion, and their cultural, and economic standard have influence on the child's ability of inference. 4) In case of the significance level 0.05 the education of the child's father and mother, the father's job, the type of habitation, their religion and their cultural and economic standard have influence on the child's ability of calculation. 5) In case of the significance level 0.05 any variable of the child's family circumstance has nothing to do with the child's memory. In case of the significance level 0, 1 the type of family and the type of habitation have effect on the child's memory. 6) In case of the significance level 0.05 the education of the child's parents, the jobs of the parents, the type of habtation, their religion, and their cultural and economic standard have influence on the child's linguistic notion. The correlation between the variable of the child's personality and that of the child's mathematical ability 1) In regard to the priority of the variables influencing the child's perception speed, the child's discretion comes first in order, and then sociability and impulsiveness of the child. 2) The child's discretion has effect on the child's space perception. 3) The child's discretion has effect on the child's ability of inference. 4) In regard to the child's ability of calculation the child's discretion comes first in order, and then impulsiveness and sociability of the child. 5) The child's discretion has effect on memory. 6) The child's discretion has effect on the child's linguistic notion.