• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5A
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• pp.467-475
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• 2009

Existing studies have suggested Universal Curve only for supplemental damping by damper. Therefore net damping has been determined by means of arithmetic summation between intrinsic, aero-damping of cable and supplemental damping of damper. However linear combination approach by means of the arithmetic summation is not enough theoretical background. So validity of this approach should be verified in order to design adequate cable-damper system by engineers. This study establishes governing differential equation which can consider intrinsic, aero-damping and supplemental damping as well. And also analysis method is solved by combination of muller method and successive iteration method. Consequently, this study succeeds in verification for validity of linear combination approach. As a result of this study, linear combination approach is limitedly effective in case of low stiffness and optimum damping coefficient of damper, short distance from support to damper, lower vibration mode, low aero-damping, and normal windy environment. Whereas this study will be effective in case of opposite conditions, and existing studies or linear combination approach occur to further error. Meaning of this study presents exact solution for net damping of cable-damper system, and verifies linear combination approach by means of the analysis method. In the future, if monitoring of optimum damping coefficient of a damper against aero-damping is feasible on time, algorithm of this study will be available for control of cable and semi-active damper system such as magneto-rheological damper.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1A
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• pp.105-113
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• 2008

Solar radiation induces non-uniform temperature distribution in the bridge structure depending on the shape of the structure and shadows cast on it. Especially in the case of curved steel box girder bridges, non-uniform temperature distribution caused by solar radiation may lead to unusual load effects enough to damage the support or even topple the whole curved bridge structure if not designed properly. At present, it is very difficult to design bridges in relation to solar radiation because it is not known exactly how varying temperature distribution affects bridges; at least not specific enough for adoption in design. Standard regulations related to this matter are likewise not complete. In this study, the thermal behavior of curved steel box girder bridges is analyzed while taking the solar radiation effect into consideration. For the analysis, a method of predicting the 3-dimensional temperature distribution of curved bridges was developed. It uses a theoretical solar radiation energy equation together with a commercial FEM program. The behavior of the curved steel box girder bridges was examined using the developed method, while taking into consideration the diverse range of bridge azimuth angles and radii. This study also provides reference data for the thermal design of curved steel box girder bridges under solar radiation, which can be used to develop design guidelines.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1B
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• pp.35-45
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• 2009

In this study, a laboratory experiment has been performed on a S-curved channel with two curved sections. In the experiments, effects of 3-D velocity structures on mixing characteristics of tracer material were investigated. As a result, it was clearly noticed that the primary flow travels taking the shortest course of the meandering channel and has a very ununiform distribution at the bends. The secondary cell which was developing at the first bend disappears at the crossover, and then, at the next bend, secondary cell is re-developing in the opposite direction. The experimental results show that mixing of tracer is significantly affected by the combined action of ununiform primary flow and secondary cell. The ununiform primary flow separates the tracer cloud in the longitudinal direction, and the secondary cell further separates the retarding tracer cloud mainly in the transverse direction. As a result, these complex flow structures cause separation and spreading of tracer cloud both in the longitudinal and in the transverse directions. The measured dimensionless transverse dispersion coefficients calculated using 2-D routing procedure ranges 0.012-0.875, and is generally proportional to width to depth ratio (W/h). The predicted values calculated by the theoretical equation overestimate slightly the measured transverse dispersion coefficients.

• Korean Journal of Social Welfare Studies
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• v.42 no.2
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• pp.381-417
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• 2011

The primary goal of this study is to examine the factors that affect how satisfied sexual minorities are with their lives. This study focuses on how sexual minorities perceive social stigma, the social influences involved in its perception, and the effects this perception has. Using stress-coping theory, this study looks at how social stigma, as a perceived stress, affects social support and self-esteem, how the stigma influences the degree to which individuals "come out" in an effort to cope, and the resultant effects of this coping mechanism on life satisfaction. The data used if from a sample of 478 individuals who self identify as gay, lesbian or bisexual. It was collected through an online survey. Using SEM, the quality was evaluated by analyzing the measurement model, and the relationship of the variables included in the theoretical model was verified by analyzing the structural model. The results of this study show that social stigma directly affects the life satisfaction of Korean sexual minorities. It significantly influences the social support they receive(from family and sexual minority peers), and their self-esteem. The degree to which the individual "comes out" is shown to affect life satisfaction as well. In contrast, the mediating effect of heterosexual support is shown to be insignificant. Based on the analyses, practical strategies regarding social stigma, social support, self-esteem, and "coming out" are suggested for sexual minorities. The social stigma should be reduced and society-scaled campaigns promoted in order to improve their level of life satisfaction. In addition, institutional protection should be developed and specialized educational courses on human rights provided which will empower these minorities with self-help mechanisms. Furthermore, issues such as establishing support system and providing a social welfare system for the sexual minority community are discussed.

• Korean Journal of Social Welfare Studies
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• v.41 no.3
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• pp.271-297
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• 2010

The purpose of this study is to verify the structural path differences among the quality of self-sufficiency services and the job satisfaction and the effectiveness of self-sufficiency. To fulfill this purpose, all data for this analysis were collected from participants who belongs to the 31 local self-sufficiency centers in Seoul. The findings are as follows. First, we found that there were no statistically significant differences among the groups of the quality of self-sufficiency services and the job satisfaction and the effectiveness of self-sufficiency according to the type of self-sufficiency program. This means all the same degrees of effectiveness that participants of social employment program and market type program and self-sufficiency community was perceived. In addition, although there were no statistically significant differences among the groups of the quality of self-sufficiency services and the job satisfaction and the effectiveness of self-sufficiency according to the type of self-sufficiency program, we found that the differences among groups existed partially with theoretical model established in this study. Through the above results, the policy limitation and suggestion were presented about effectiveness of current self-sufficiency.

• Asia Marketing Journal
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• v.15 no.2
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• pp.49-73
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• 2013

In this study, the author develops and tests a model that incorporates the mediating effects of two frontline employee psychological variables (emotional exhaustion and intrinsic motivation) based on job demand and resource model. As a form of environmental resource, person-organization fit was proposed as a leading factor of frontline employee boundary spanning behavior through emotional exhaustion and intrinsic motivation. All measures were adapted from or developed based on prior research. Data for the study were collected from a cross-sectional sample of retail bank employees in South Korea. Questionnaires were distributed to 500 frontline employees across several banks. Of these, 322 usable questionnaires were returned. To analyze the data, a structural equation model procedure using LISREL 8.5 was employed. Results show that an employee's perceived fit with his/her organization enhances intrinsic motivation and reduces emotional exhaustion. These mechanisms, in turn, increase the employee's boundary spanning behavior. These results support the notion that person-organization fit should be one of the factors affecting motivation, affect and attachment, and extends such an understanding to a purely service-based environment among customer contact employees. Results also confirms that P-O fit can be viewed as environmental resources, and the JD-R model provides a theoretical base in further studying the antecedent role of P-O fit on frontline employees's boundary spanning behavior through intrinsic motivation and emotional exhaustion. These results suggest that organizations have to do their best to manage P-O fit, be it through employee screening or training and workshops to try and align organization and employee values and objectives. If managers of organizations are positively evaluated by the employees, it will be easier for them to, give things of value to employees, such as sense of direction, values, and recognition, and receive other things in return such as esteem and responsiveness. Consequently, organizational leaders are not only able to manage employee experiences, but also their fit with the organization. Even if a manager cannot control employee P-O fit, this research suggests, that a focus on reducing emotional exhaustion rather than increasing intrinsic motivation seems optimal. This research also supports the idea that motivation has a direct association with a frontline employee's boundary spanning behavior. Even in situations where emotional exhaustion cannot be reduced, organizations may still influence frontline behaviors through motivation.

• Asia Marketing Journal
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• v.10 no.4
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• pp.1-33
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• 2009

This research investigates the effect of brand-self identification on brand attachment and brand commitment focusing on luxury brand. Another purpose of this study is to examine how the relationships among brand identification, brand attachment and brand committment are moderated by consumers' regulatory focus. Structural Equation Modeling using 214 questionnaires was conducted to test hypothesized model. The results reveal that perceived luxury brand personality including excitement, competence, and sophistication influences brand-self identification positively, which in turn has a signifiant positive effect on the brand attachment. It is also found that consumers' emotional attachment to luxury brands has a positive influence on the luxury brand commitment while the effect of the brand-self identification on the brand commitment is not signifiant. This finding strongly supports that brand attachment and brand commitment are distinct construct, which confirms the results of the previous studies. In addition, the results show that consumers-luxury brands relationships are moderated by consumers' regulatory focus. This finding explains that prevention-focused individuals who have interdependent self-view respond to the loss caused by relationship break more sensitively compared to the promotion-focused consumers. Finally, based on the findings of this study, theoretical contribution and managerial implications are discussed.

• Asia Marketing Journal
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• v.8 no.1
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• pp.105-132
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• 2006

The major purpose of this study is to investigate the impact of environmental uncertainties and logistics resources capabilities mediated by relational norms and logistics services on logistics performance in the industrial products. The 272 data were collected from the key informants who were working at the logistics-related departments in the H Heavy Industries & Construction and HSD Engine. The following results were verified using structural equation modeling. First, environmental uncertainties such as dynamism and heterogeneity unexpectedly had insignificant effects on relational norms such as information exchange and flexibility and logistics services such as product availability and on-time delivery. Second, logistics resource capabilities showed unique effects based upon its component's characteristics. For example, Logistics Information Systems did not have direct impact on logistics services but had indirect effect on logistics services via relational norms. On the other hand, logistics resources such as logistics specific assets and transportation service competencies had direct impact on logistics services but not on relational norms. Third, relational norms between transaction partners significantly affected logistics services but had insignificant effects on logistics performance such as logistics costs reduction and delivery qualities. Fourth, consistent with several studies, excellent logistics services between industrial purchaser and suppliers based upon relational norms did have significant effect on logistics performance such as delivery consistency and delivery qualities. Finally, the empirical results in this study could be strategic logistics management guidelines based upon the theoretical relationships among the environmental uncertainties, logistics information systems, logistics resources, relational norms, logistics services, and logistics performance.

• Journal of Venture Innovation
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• v.5 no.4
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• pp.91-108
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• 2022

This study is an empirical analysis regarding what kind of factors affect the intention to use autonomous vehicles. For the empirical analysis the research model was derived from value-based adoption model base and integrated some aspects that only autonomous vehicles have. At default variables of VAM are usefulness, enjoyment, technicality, perceived cost, some autonomous vehicle related variables were added, and those are convenience, safety, security, social influence. A survey was done in order to empirically analyze with this research model, and 216 valid survey answers were chosen to analyze. Empirical analysis was done by structural equation using AMOS24. The result of empirical analysis were as follows. Variables usefulness, enjoyment, safety, security had a significant positive effect on perceived value. Technicality and perceived cost had a significant negative effect of perceived value. In addition, security and social influence had no significant effect on perceived value. Furthermore, perceived value had significant positive effect on intention to use. Among the variables that came out to be significantly positive, the most influencing variable was safety, followed by convenience, perceived cost, enjoyment, usefulness and then technicality. In addition, the analysis of mediating effect of perceived value shows that usefulness, enjoyment, convenience, safety, technicality, perceived cost had mediating role towards intention to use. However, security and social influence had no siginificant mediating effect towards intention to use. Considering all these research results this study has provided theoretical and practical implications to researchers on the intention to use autonomous vehicles.

• Information Systems Review
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• v.22 no.2
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• pp.101-120
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• 2020

This study investigates the effects of privacy psychological characteristics of B2C logistics services users on their willingness to comply with their logistics companies' information protection policy. Using cognitive valence theory as a theoretical framework, this study proposes a research model to examine the relationships between users' logistics security knowledge, privacy trust, privacy risk, privacy concern, and their willingness of information protection policy compliance. To test the proposed model, we conducted a survey from actual users of logistics services and collected valid 151 samples. We analyzed the data using a structural equation modeling software. The empirical results show that logistics security knowledge positively affects privacy trust; privacy concern positively influences privacy risk; privacy trust, privacy risk, and privacy concern positively influence behavioral willingness of compliance. However, logistics security knowledge does not affect behavioral willingness of compliance. The results of the study provide several contributions to the literature of B2C logistics services domain and managerial implications to logistics services companies.