• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.264-267
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• 2008

Dual-cooled fuel with inner and outer flow channel was proposed for high burup, next generation nuclear fuel design. The annular cylinder of dual cooled fuel has higher structural strength compared to the conventional one, but also have concerns about flow induced vibration due to an additional flow of inner channel and the difference of flow velocity in between inner and outer channel. In this study, the dynamic stability of flexible, annular cylinder was evaluated according to the flow variation and compared to the that of the conventional PWR fuel rod. Centrifugal and Coriolis force by the additional flow in the inner channel were added in the dynamic equation of flexible beam in uniform, external, and axial flow. Complex eigenfrequency was calculated by the finite element method. Stability margin of annular cylinder compared to the solid cylinder and change of the dynamic characteristic are presented and discussed as a analysis results.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.1
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• pp.59-68
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• 2002

The cylindrical Upper Guide Structure assembly of the reactor intervals wish the Core Support Barrel and the Inner Barrel Assembly is subjected to flow induced loads horizontally which include random pressure fluctuation due to turbulent flow and pump pulsation pressures. The purpose of this papers is to perform random vibration and harmonic response analyses fort flow induced loads. The dynamic response characteristics due to random turbulence and pump pulsation loads were evaluated using the lumped mass beam model. Especially the model considered the annulus effects due to water gaps existing between cylindrical structures such as the Upper Guide Structure Barrel, the Core Support Barrel, and the Inner Barrel Assembly. The effect of the Inner Barrel Assembly inside the Upper Guide Structure assembly was studied. The peak dynamic responses lot each loading condition due to the addition of IBA were affected by the natural frequencies of the structures. Therefore the peak dynamic responses of the structures should be conservatively obtained from evaluation of dynamic analysis for various loading conditions.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.12
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• pp.28-36
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• 1998

This investigation is the result of a structural analysis by the finite element method and static loading test for the optimal structural design of an electric railway vehicle made of stainless 301L materials. We analyzed the stress and displacement of the existing electric car-body structure for predicting the position of concentrated stress, the flow of stress, rigidity to be occurred in the car-body structure when it is subjected to the vertical load. It was exposed that the side sills and window corners around the bolsters are the weak parts of the electric car-body structure because the bolsters of the electric car-body structure were subjected to the vertical load and dynamic load to be occurred during running. The flow of stress and the cause of stress concentration in the weak zone were studied in order to prevent the concentration of stress and buckling. The rearrangement of the structure and the selection of the beam elements were also carried out for optimum design of the structure.

• The Journal of Industrial Distribution & Business
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• v.14 no.12
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• pp.11-21
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• 2023

Purpose: This study aims to investigate the impact of mobile shopping app components on shopping flow and the continuous usage intention of the shopping apps in the rapidly growing mobile market facilitated by advancements in the mobile environment. Research Methodology: A survey was conducted, targeting users aged 20 and older with experience in using mobile shopping apps. The responses of 456 participants were analyzed through frequency analysis, exploratory factor analysis, reliability analysis, confirmatory factor analysis, and structural equation modeling. Results: The study found that within the components of mobile shopping apps, enjoyment significantly impacted both shopping flow and the continuous usage intention of shopping apps. The diversity of product assortment had a significant effect only on shopping flow. The usefulness and ease of use influenced on the intention to continue using shopping apps. Conclusions: Based on the findings, it is recommended that shopping app operators try to identify essential components for stimulating user interest and engagement when developing or modifying apps. Additionally, a diverse range of products enhances the shopping experience and drives spontaneous purchases. Furthermore, providing an easy interface and minimizing the effort required, this experience can enhance user perception of its value and sustain consumers' continuous usage intention of the shopping app.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.8
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• pp.573-578
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• 2010

Topological matrix which reflects characteristics of network connectivity has been widely used in efficient solving for complicated flow network. Using topological matrix, one can easily define continuity at each node of flow network and make algorithm to automatically generate continuity equation of matrix form. In order to analyze flow network completely it is required to satisfy energy conservation in closed loops of flow network. Fundamental cycle retrieving algorithm based on graph theory automatically constructs energy conservation equation in closed loops. However, it is often accompanied by NP-complete problem. In addition, it always needs fundamental cycle retrieving procedure for every structural change of flow network. This paper proposes alternative mathematical method to analyze flow network without fundamental cycle retrieving algorithm. Consequently, the new mathematical method is expected to reduce solving time and prevent error occurrence by means of simplifying flow network analysis procedure.

• International Commerce and Information Review
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• v.10 no.2
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• pp.63-87
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• 2008

This study investigates the relationship between perceived system characteristics of Internet shopping mall and loyalty, and examines how perceived website attractiveness and flow play mediating roles between perceived system characteristics of Internet shopping mall and affective commitment in the context of Internet clothing shopping mall. For these purposes, the author developed a structural model which consists of several variables. In this model, perceived system characteristics of Internet shopping mall that consist of such as familiarity, reputation, uniqueness, positive emotion, self-efficacy, and interactivity were proposed to affect the website attractiveness and flow, and in turn, result in higher affective commitment. Thus, perceived website attractiveness and flow were proposed as core mediating variables between perceived mobile service characteristics and affective commitment. To test unidimensionality and nomological validity of the measures of each construct, the author employed scale refinement procedure. The results of reliability test with Cronbach's, and confirmatory factor analysis warranted unidimensionality of the measures for each construct. In addition, nomological validity of the measures was warranted from the result of correlation analysis.

• Journal of the Korean Society of Safety
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• v.27 no.4
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• pp.128-133
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• 2012

This research has analyzed factors affecting customers' satisfaction when they use parking lots of big retailers so that, in case of constructing, operating or managing such retailers, proper measures can be come up with. The analysis has been implemented on the basis of survey, and influence factors including entry/exit lamp, parking cars' traffic flow, parking type, pedestrians' movement after parking and safety. Parking lot users' satisfaction has been analyzed by using the Structural Equation Modelling and, as a result of it, in case of a detached or single building, pedestrians' movement flow after parking contributed the most to the users' satisfaction, while, in case of multipurpose complex, parking cars' traffic flow has the most influential factor. It is interpreted that users of a single building put a bigger emphasis on entry to the shop and their way back to the parked area after their shopping while customers of multipurpose complex might have various purposes of visiting the place and there are relatively more cars so that they put more emphasis on traffic counterflow, other cars and pedestrians.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.265-268
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• 2006

The preliminary design of a deep-sea injection system for carbon dioxide ocean sequestration is performed. Common functional requirements for a deep-sea injection system of mid-depth type and lake type are determined, Liquid transport system, liquid storage system and liquid injection system are conceptually determined for the functional requirements. For liquid injection system, the control of flow rate and temperature of liquid $CO_2$ in the injection pipe is needed in the view of internal flow. The function of depressing VIV(Vortex Induced Vibration) is also required in the view of dynamic stability of the injection pipe. A case study is performed for $CO_2$ sequestration capacity of 10 million tons per year. In this study, the total number of injection ships, the flow rate of liquid $CO_2$ and the configuration of a injection pipe are designed. The static structural analysis of the injection pipe is also performed. Finally the preliminary design of a deep-sea injection system is proposed.

• Journal of Digital Convergence
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• v.14 no.3
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• pp.409-418
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• 2016

This study examines how instructor's attractiveness perceived by pilates participants affects participants' flow and passion. The subjects for this study were 214 participants who participated in pilates in Seoul. The reliability and validity test of the questionnaire were conducted by using SPSS & AMOS Window 18.0 program; the results of descriptive analysis, factor analysis, correlation analysis, structural equation model are as follows; First, the instructors' attractiveness affects pilates participants' flow. Second, the instructors' attractiveness has influence on the participants' passion. Third, pilates participants' flow affects their passion. Lastly there is a causal relationship between instructors' attractiveness, flow and passion of pilates participants.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.2
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• pp.311-315
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• 2012

Diaphragm type noncontact automatic control valve is a valve for controling acidic PR(Photo Resist) liquid used in the semiconductor process. PR is photosensitive liquid that changes phases depending on light transmittance. PR is very toxic and expensive; the purpose of this paper is to address methods that prevent loss due to leaks. The design of noncontact precise automatic control valve is expected to play an important role in controlling fluid flow, therefore influencing energy conservation and environmental improvement. In this paper, diaphragm type automatic control valve's part design, assembly and simulation are introduced. Also, through the analysis of fluid flow the valve's internal velocity, pressure, and turbulent intensity are interpreted. This paper proposes to contribute to the improvement of the valve's performance.