• Journal of Digital Convergence
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• v.19 no.1
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• pp.389-399
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• 2021

The research background of this paper is because the u-convergence information system applying flow theory lacks the measurement of tourist satisfaction. The purpose and research method of this study are as follows. The first is the suggestion of flow relation information display format algorithm. Second, by combining this algorithm and flow theory, a pattern algorithm was created according to the content information quality and the personality type of tourists. The expected effect of this study is to derive the success factors of the u-convergence information system by generating a pattern algorithm according to the flow relationship information display format and the tourist's personality type. The limitations of this paper are limited to one area, and objectivity is poor due to the lack of data and small area. In the future, it is necessary to evaluate the effectiveness through analysis after applying the method presented to other tourist destinations. Future tasks will need to be supplemented with data from expert groups and objectivity in various regions.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.10
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• pp.1238-1246
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• 2004

Momentum exchange theory has been generally used for an analysis of the regenerative turbomachines due to its direct description of the complicate circulatory flow. However, because its application is limited only to linear region and its model equations are incomplete on three variables, it needs further refinements. In the present study it is improved by introducing a central pivot of circulatory flow. Also, by assuming linear circulatory velocity distribution, mean radii of inlet and outlet flows through the impeller are newly suggested. By applying control volume analysis to both linear region and the acceleration region, the governing equation on the circulatory velocity is derived. As a result, systematic performance analysis on the entire region of the incompressible regenerative turbomachines can be carried out based on the proposed model equations.

• 유체기계공업학회:학술대회논문집
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• 1998.12a
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• pp.64-69
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• 1998

In this study, a preliminary design method of the axial fan was systematically established based on the two-dimensional cascade theory. Flow deviation, lift coefficient, distribution of velocity and pressure coefficient on blade surfaces were predicted by an inviscid theory of Martensen method, which was also applied to select an airfoil of required performance in the present design process. The aerodynamic performance of designed blades can be predicted quickly and reasonably by using the through-flow calculation method in the preliminary design process. It would be recommendable to adopt three-dimensional viscous flow calculation at the final design refinement stage.

• Korea-Australia Rheology Journal
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• v.21 no.4
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• pp.245-268
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• 2009

Recent developments in dilute polymer solution rheology are reviewed, and placed within the context of the general goals of predicting the complex flow of complex fluids. In particular, the interplay between the use of polymer kinetic theory and continuum mechanics to advance the microscopic and the macroscopic description, respectively, of dilute polymer solution rheology is delineated. The insight that can be gained into the origins of the high Weissenberg number problem through an analysis of the configurational changes undergone by a single molecule at various locations in the flow domain is discussed in the context of flow around a cylinder confined between flat plates. The significant role played by hydrodynamic interactions as the source of much of the richness of the observed rheological behaviour of dilute polymer solutions is highlighted, and the methods by which this phenomenon can be incorporated into a macroscopic description through the use of closure approximations and multi scale simulations is discussed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.5
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• pp.1426-1435
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• 1996

In this paper. a network theory for generaltransmission systme was extended considering the direction of power flow. Also, a modified network model was suggested for a node with 4 shafts in order to verify the power flow. Based on the extended network theory, a simulation program was developed to analyze a hydro-mecaanical tranmission(HMT) system consistion of two hydrostatic pump motors, severeal planetary gear trains steer differential gear. The simulation result showed that the extendednotwork analysis program develped can predict the power circulation as well as the magnitude of torque and speed for each transmission element and can be used design tool for genaral power transmission system.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.11
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• pp.1603-1609
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• 1998

Numerical solutions of Stokes flow through periodic arrays of cylinders were sought using Darcy's law and homogenization theory. Drag and lift forces of each cylinder were computed for various attack angles and pitch-to-diameter ratios. It was found that drag force decreased as principal pressure gradient direction deviated from array direction and that drag force increased exponentially as pitch-to-diameter ratio approached unity. Similar tendency was found in lift force except that lift force increased and then decreased in quadratic manner as attack angle varied.

• Educational Technology International
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• v.12 no.2
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• pp.1-18
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• 2011

This study intends to examine the effects of motivational scaffolding in Computer-Supported Collaborative Learning (CSCL). This study was focused on the following two questions. Do motivational scaffolding lead to positive effects on the process in CSCL? Do motivational scaffolding lead to positive effects on the outcome in CSCL? In order to identify strategies for motivational scaffolding, we reviewed the "Flow Theory." Based on literature reviews, principles and strategies were drawn for the motivational scaffolding. An experimental study was conducted in order to investigate the effects of motivational scaffolding on process and outcome. In this study, 87 undergraduate students were divided into two different groups (control group, experimental group). Motivational scaffolding was provided to experimental group. The process was analyzed by examining learners' satisfaction in process. The outcome was analyzed by examining learners' satisfaction in product, group coherence, and quality of product. The difference between the two groups was statistically significant. From these results, we concluded that motivational scaffolding led to positive effects on process and outcome in CSCL environment.

• Therapeutic Science for Rehabilitation
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• v.10 no.3
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• pp.71-81
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• 2021

Introduction : The purpose of this article was to introduce the theory of flow experience to occupational therapy for various therapeutic interventions to improve the subject's physical function, activity, and participation. Review : To understand the flow experience in occupational therapy, this study summarized the concept and characteristics of the flow experience, the stages and the scientific characteristics of the brain, measurement methods, and related studies through a review of domestic and foreign literature. In occupational therapy, the subject's flow experience can be defined as 'a psychological state in which the subject is completely flow in the therapeutic activity he is doing while forgetting the passage of time'. Subjects perceived a clear goal for the task and experienced engagement when the challenge was balanced with a high level of skill. In a previous study, positive changes in attention and concentration, executive function, upper extremity function, and performance of daily living activities were confirmed in subjects who encountered the flow experience. Conclusion : If the subject's flow experience in various therapeutic interventions in domestic occupational therapy is considered, the treatment effects will be further promoted.

• Journal of Engineering Education Research
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• v.20 no.4
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• pp.61-66
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• 2017

Automatic flow control system composed by hardware and software was designed and fabricated to be used as teaching tool of feedback control theory in university experimental class. This system includes hardwares like data acquisition board, flow measuring device, transmitters, and the pneumatic valve, and software like LabView program for the monitoring and control of flow rates. The system was designed as the student can see the control effect of not only set point but also disturbance changes. Also the LabView program was composed for the calculation of controller parameters of both Ziegler-Nichols and Cohen-Coon tuning. The students can apply both tuning constants and compare the control performances. This system will provide the easy way for the students to understand the function and specification of control hardwares, and to raise the programing ability of control software.

• Journal of the Korean Chemical Society
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• v.15 no.6
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• pp.303-312
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• 1971

Dependence of the flow behavior of aqueous suspension of Black Hills bentonite on the concentration and the types of electrolytes was stydied. The flow properties were measured with a Couette-type totational viscometer. On addition of monovalent cations, the apparent viscosity determined from the reproducible flow curves (shear rate vs. shear stress) decreased followed by a rise as the ionic concentration further increased. Addition of multivalent cations (di- and tri-) resulted in the viscosity which increased to a maximum then decreased to a constant value. Anions of different chatges produced essentially the same relationship between viscosity and electrolyte concentration. The flow behavior of the electrolyte-containing suspensions was rationalized in terms of the Derjaguin-Landau-Verwey-Overbeek theory of colloidal stability and the generalized theory of viscosity.