• Structural Engineering and Mechanics
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• 제75권3호
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• pp.327-337
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• 2020

The stability and dynamic performance of a flapper-nozzle servo valve depend on several factors, such as the motion of the armature component and the deformation of the spring tube. As the only connection between the armature component and the fixed end, the spring tube plays a decisive role in the dynamic response of the entire system. Aiming at predicting the vibration characteristics of the servo valves to combine them with the control algorithm, an innovative dynamic stiffness based on a distributed parameter model (DPM) is proposed that can reflect the dynamic deformation of the spring tube and a suitable discrete method is applied according to the working condition of the spring tube. With the motion equation derived by DPM, which includes the impact of inertia, damping, and stiffness force, the mathematical model of the spring tube dynamic stiffness is established. Subsequently, a suitable program for this model is confirmed that guarantees the simulation accuracy while controlling the time consumption. Ultimately, the transient response of the spring tube is also evaluated by a finite element method (FEM). The agreement between the simulation results of the two methods shows that dynamic stiffness based on DPM is suitable for predicting the transient response of the spring tube.

• 대한가정학회지
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• 제42권2호
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• pp.133-150
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• 2004

This study aimed to find the effect of parental experiences from the family-of-origin and childrearing behaviors on their children's behavioral problems, as well as if this path differed according to the child's gender. The subjects were 1247, 4/sup th/ and 5/sup th/ graders in eight elementary schools and their parents in Seoul, Pusan, and Daejon, Korea. The data were analyzed using the Structural Equation Modeling(SEM) to verify the theoretical models among the variables. The results showed differences between the father-child model and the mother-child model on the pathways of the impact of parental experiences from the family-of-origin upon the child's internalizing and externalizing behavioral problems through parental negative rejection and permission childrearing behaviors. Specifically, 1) the father-child model showed a gender difference on the pathways of the impact of the father's experiences from the family-of-origin upon the child's internalizing and externalizing behavioral problems through the father's rejection and permission childrearing behaviors; whereas, 2) The mother-child model showed no gender difference on the pathways of the impact of the mother's experiences from the family-of-origin upon the child's internalizing and externalizing behavioral problems through the mother's negative childrearing behaviors.

• 한국산학기술학회논문지
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• 제10권12호
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• pp.3775-3781
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• 2009

본 연구의 목적은 모바일 상거래의 채널만족과 채널선호에 영향을 미치는 요인을 분석하는 것이다. 기술수용모형, 거래비용이론 그리고 서비스 품질에 대한 이론적 배경을 바탕으로 연구모형을 설정하였으며, 모바일 사용자 320명을 대상으로 AMOS 7.0 통계패키지를 이용하여 실증연구를 수행하였다. 연구결과, 유용성, 자산특유성, 불확실성, 신뢰, 응답성이 채널만족에 유의한 영향을 미쳤으며, 채널만족이 채널선호에 유의한 영향을 미치는 것으로 나타났다.

• Asian Journal of Business Environment
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• 제4권1호
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• pp.15-23
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• 2014

Purpose - In this study, we inspected the effects of public-service advertising (PSA) and commercial advertisements on consumers' social and emotional values. Specifically, we include source credibility on advertising models as a mediating variable to compare the path difference between the social and emotional value of consumers, and to test the appropriateness of advertising expenses. Research design, data, and methodology - A total of 219 copies of effective questionnaires were used and methodologies such as Cronbach's alpha, paired samples t-test, and structural equation modeling (SEM) were conducted. Results - The results showed that the consumer model was effective at PSA, while celebrities and CEOs were effective at commercial advertising. Further, only credibility (among source credibility) made a significant difference in the test of PSA models of both PSA and commercial advertising that consumers preferred. Conclusions - The advertising model types varied depending on advertising types (for example, PSA and commercial advertising). Therefore, celebrities and CEOs appearing in commercial advertising should have no ethical or moral defect by self-control, and marketers should elect the model considering such a fact.

• 한국식품조리과학회지
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• 제27권3호
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• pp.71-79
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• 2011

The purpose of this study was to understand effects of culinary staff's technology kitchen system upon perceived ease of use, usefulness, attitude, and job performance in the foodservice industry. Based on a total of 387 samples obtained from empirical research, this study reviewed the reliability and fitness of the research model and verified a total of four hypotheses using the Amos program. The hypothesized relationships in the model were tested simultaneously using a structural equation model (SEM). The proposed model provided an adequate fit to the data, ${\chi}^2$=226.501 (df=85), p<.001, CMIN/df 2.665, RMR .066, GFI .927, NFI .926, IFI .952, TLI .941, CFI .952. The results show that culinary staff's perceived ease of use(${\beta}$=.534) had a significant positive effect on perceived usefulness. Also, perceived ease of use (${\beta}$=.350) and perceived usefulness (${\beta}$=.297) had a positive significant effect on attitude. Further, attitude (${\beta}$=1.647) had a significant positive effect on job performance. Limitations and future research directions are also discussed.

• 유통과학연구
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• 제11권11호
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• pp.41-47
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• 2013

Purpose -This paper aims to understand how easy and convenient it is for consumers to use mobile services. A mobile service combines hardware and software with information technology. To specifically meet the needs of users of mobile applications, the context of usability was identified in consumer mobile services. Research Design, Data, and Methodology - For usability measurement and evaluation, appliances and software were the main target: this applied to an expanding range, such as a Personal Digital Assistant (PDA), mobile phones, and wired and wireless integrated services. This study extended the Technology Acceptance Model (TAM) by examining the roles of two characteristics of mobile applications'usage: usability and usefulness. Results - The study tested the research model using a structural equation modeling (SEM) technique. Results showed no significant differences between the two models. Usability comprised learnability, efficiency, memorability, errors, and satisfaction: the motivation for using a mobile application was understood as being the usefulness and easy-of-use of the mobile application. This empirical study validated the proposed research model and hypotheses, and found that the hypotheses could be supported. Finally, the phenomena derived from the causal relationships in usability were identified, and their implications considered.

• 한국식품조리과학회지
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• 제26권3호
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• pp.272-280
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• 2010

The purpose of this study was to understand the interrelationships between the customers' perception of verbal and nonverbal communication, customers' trust and satisfaction in the family restaurant. Based on a total of 310 samples that were obtained from empirical research, this study reviewed the reliability and fitness of the research model and verified a total of 2 hypotheses using the Amos program. The hypothesized relationships in the model were tested simultaneously using a structural equation model(SEM). The proposed model provided an adequate fit to the data, $X^2$=953.126(df=417), p<.001, CMIN/df 2.286, GFI .831, NFI .889, IFI .934, TLI .926, CFI .934. The results showed that employees' verbal communication ($\beta$=.264), paralanguage ($\beta$=.172) and physical appearance ($\beta$=.120) among the nonverbal communications had a significant positive effect on the customers' trust. In addition, the customers' trust ($\beta$=.644) had a significant positive effect on the customer satisfaction. Limitations and future research directions are also discussed.

• Structural Engineering and Mechanics
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• 제5권1호
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• pp.105-113
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• 1997

This paper proposes a model for simulating concrete shrinkage taking into account aggregate restraint. In the model, concrete is regarded as a two-phase material based on shrinkage property. One is paste phase which undergoes shrinkage. Another is aggregate phase which is much more volumetrically stable. In the concrete, the aggregate phase is considered to restrain the paste shrinkage by particle interaction. Strain compatibility was derived under the assumption that there is no relative macroscopic displacement between both phases. Stresses on both phases were derived based on the shrinking stress of the paste phase and the resisting stress of the aggregate phase. Constitutive relation of paste phase was adopted from the study of Yomeyama, K. et al., and that of the aggregate phase was adopted from the author's particle contact density model. The equation for calculating concrete shrinkage considering aggregate restraint was derived from the equilibrium of the two phases. The concrete shrinkage was found to be affected by the free shrinkage of the paste phase, aggregate content and the stiffness of both phases. The model was then verified to be effective for simulating concrete shrinkage by comparing the predicted results with the autogeneous and drying shrinkage test results on mortar and concrete specimens.

• The Journal of Asian Finance, Economics and Business
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• 제7권11호
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• pp.789-800
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• 2020

This study aims to examine the effect of perceived usefulness (PU), perceived ease of use (PEU), trust (TR), subjective norm (SN), and attitude (AT) on customer's Intention to Adopt Internet Banking (IAIB) at Islamic banks and conventional banks before and during the Covid-19 pandemic in Indonesia. The research model is based on the Theory of Planned Behavior (TPB) and the Technology Acceptance Model (TAM). This study involves 213 respondents for Islamic banks and 410 respondents for conventional banks from 25 provinces in Indonesia. Data was analyzed using partial least square (PLS) regression with the Structural Equation Model (SEM) method. The result of data analysis confirms several hypotheses taken from the literature. The results before the Covid-19 pandemic showed that AT and SN influence IAIB in Islamic banks. Whereas in conventional banks, AT, PU, SN, and TR influence IAIB. While during the Covid-19 pandemic, it shows that the AT, PU, IB, SN, and customer TR influence IAIB in Islamic banks and conventional banks. From the analysis, it was found that the PEU variable did not have a significant effect on the intention of customers of Islamic banks and conventional banks to use Internet banking.

• The Journal of Asian Finance, Economics and Business
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• 제7권10호
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• pp.885-896
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• 2020

The purpose of this study is to shed light on the driving motivations of contributing social word of mouth on social networking sites (sWOM) toward both tangible and intangible products. In order to develop a research model, this study adopts the motivation theory and TAM model. Data was collected from 904 members of the cosmetic and restaurant communities by using the snowball method. After assessing the validity of all constructs, the structural equation modeling (SEM) is used to test the proposed hypotheses. Results show that personal motivations (satisfaction, opinion leadership, self-enhancement, and economic incentives) and characteristics of sWOM (Perceived Usefulness and Ease of Use) have positive effect on exposure and engagement behaviors. Here are our specific findings, (1) customer satisfaction positively affects online interactions on SNSs such as Like or Sharing a content; (2) sWOM contribution behavior exists in two structures (Exposure and Engagement) and affects each other; (3) This study combines two groups of personal motivation and TAM to conceptualize a research model; and (4) The motivations of contributing sWOM between a specified service and product are rather similar. These findings help digital managers to understand consumers' behavioral contributions on SNSs and also provide interesting insights for marketers.